rbd.c 150.3 KB
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/*
   rbd.c -- Export ceph rados objects as a Linux block device


   based on drivers/block/osdblk.c:

   Copyright 2009 Red Hat, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.



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   For usage instructions, please refer to:
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                 Documentation/ABI/testing/sysfs-bus-rbd
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 */

#include <linux/ceph/libceph.h>
#include <linux/ceph/osd_client.h>
#include <linux/ceph/mon_client.h>
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#include <linux/ceph/cls_lock_client.h>
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#include <linux/ceph/striper.h>
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#include <linux/ceph/decode.h>
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#include <linux/parser.h>
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#include <linux/bsearch.h>
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#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
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#include <linux/blk-mq.h>
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#include <linux/fs.h>
#include <linux/blkdev.h>
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#include <linux/slab.h>
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#include <linux/idr.h>
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#include <linux/workqueue.h>
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#include "rbd_types.h"

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#define RBD_DEBUG	/* Activate rbd_assert() calls */

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/*
 * Increment the given counter and return its updated value.
 * If the counter is already 0 it will not be incremented.
 * If the counter is already at its maximum value returns
 * -EINVAL without updating it.
 */
static int atomic_inc_return_safe(atomic_t *v)
{
	unsigned int counter;

	counter = (unsigned int)__atomic_add_unless(v, 1, 0);
	if (counter <= (unsigned int)INT_MAX)
		return (int)counter;

	atomic_dec(v);

	return -EINVAL;
}

/* Decrement the counter.  Return the resulting value, or -EINVAL */
static int atomic_dec_return_safe(atomic_t *v)
{
	int counter;

	counter = atomic_dec_return(v);
	if (counter >= 0)
		return counter;

	atomic_inc(v);

	return -EINVAL;
}

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#define RBD_DRV_NAME "rbd"
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#define RBD_MINORS_PER_MAJOR		256
#define RBD_SINGLE_MAJOR_PART_SHIFT	4
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#define RBD_MAX_PARENT_CHAIN_LEN	16

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#define RBD_SNAP_DEV_NAME_PREFIX	"snap_"
#define RBD_MAX_SNAP_NAME_LEN	\
			(NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))

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#define RBD_MAX_SNAP_COUNT	510	/* allows max snapc to fit in 4KB */
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#define RBD_SNAP_HEAD_NAME	"-"

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#define	BAD_SNAP_INDEX	U32_MAX		/* invalid index into snap array */

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/* This allows a single page to hold an image name sent by OSD */
#define RBD_IMAGE_NAME_LEN_MAX	(PAGE_SIZE - sizeof (__le32) - 1)
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#define RBD_IMAGE_ID_LEN_MAX	64
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#define RBD_OBJ_PREFIX_LEN_MAX	64
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#define RBD_NOTIFY_TIMEOUT	5	/* seconds */
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#define RBD_RETRY_DELAY		msecs_to_jiffies(1000)

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/* Feature bits */

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#define RBD_FEATURE_LAYERING		(1ULL<<0)
#define RBD_FEATURE_STRIPINGV2		(1ULL<<1)
#define RBD_FEATURE_EXCLUSIVE_LOCK	(1ULL<<2)
#define RBD_FEATURE_DATA_POOL		(1ULL<<7)
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#define RBD_FEATURE_OPERATIONS		(1ULL<<8)
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#define RBD_FEATURES_ALL	(RBD_FEATURE_LAYERING |		\
				 RBD_FEATURE_STRIPINGV2 |	\
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				 RBD_FEATURE_EXCLUSIVE_LOCK |	\
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				 RBD_FEATURE_DATA_POOL |	\
				 RBD_FEATURE_OPERATIONS)
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/* Features supported by this (client software) implementation. */

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#define RBD_FEATURES_SUPPORTED	(RBD_FEATURES_ALL)
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/*
 * An RBD device name will be "rbd#", where the "rbd" comes from
 * RBD_DRV_NAME above, and # is a unique integer identifier.
 */
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#define DEV_NAME_LEN		32

/*
 * block device image metadata (in-memory version)
 */
struct rbd_image_header {
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	/* These six fields never change for a given rbd image */
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	char *object_prefix;
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	__u8 obj_order;
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	u64 stripe_unit;
	u64 stripe_count;
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	s64 data_pool_id;
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	u64 features;		/* Might be changeable someday? */
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	/* The remaining fields need to be updated occasionally */
	u64 image_size;
	struct ceph_snap_context *snapc;
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	char *snap_names;	/* format 1 only */
	u64 *snap_sizes;	/* format 1 only */
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};

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/*
 * An rbd image specification.
 *
 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
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 * identify an image.  Each rbd_dev structure includes a pointer to
 * an rbd_spec structure that encapsulates this identity.
 *
 * Each of the id's in an rbd_spec has an associated name.  For a
 * user-mapped image, the names are supplied and the id's associated
 * with them are looked up.  For a layered image, a parent image is
 * defined by the tuple, and the names are looked up.
 *
 * An rbd_dev structure contains a parent_spec pointer which is
 * non-null if the image it represents is a child in a layered
 * image.  This pointer will refer to the rbd_spec structure used
 * by the parent rbd_dev for its own identity (i.e., the structure
 * is shared between the parent and child).
 *
 * Since these structures are populated once, during the discovery
 * phase of image construction, they are effectively immutable so
 * we make no effort to synchronize access to them.
 *
 * Note that code herein does not assume the image name is known (it
 * could be a null pointer).
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 */
struct rbd_spec {
	u64		pool_id;
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	const char	*pool_name;
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	const char	*image_id;
	const char	*image_name;
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	u64		snap_id;
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	const char	*snap_name;
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	struct kref	kref;
};

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/*
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 * an instance of the client.  multiple devices may share an rbd client.
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 */
struct rbd_client {
	struct ceph_client	*client;
	struct kref		kref;
	struct list_head	node;
};

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struct rbd_img_request;

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enum obj_request_type {
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	OBJ_REQUEST_NODATA = 1,
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	OBJ_REQUEST_BIO,	/* pointer into provided bio (list) */
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	OBJ_REQUEST_BVECS,	/* pointer into provided bio_vec array */
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	OBJ_REQUEST_OWN_BVECS,	/* private bio_vec array, doesn't own pages */
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};
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enum obj_operation_type {
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	OBJ_OP_READ = 1,
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	OBJ_OP_WRITE,
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	OBJ_OP_DISCARD,
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};

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/*
 * Writes go through the following state machine to deal with
 * layering:
 *
 *                       need copyup
 * RBD_OBJ_WRITE_GUARD ---------------> RBD_OBJ_WRITE_COPYUP
 *        |     ^                              |
 *        v     \------------------------------/
 *      done
 *        ^
 *        |
 * RBD_OBJ_WRITE_FLAT
 *
 * Writes start in RBD_OBJ_WRITE_GUARD or _FLAT, depending on whether
 * there is a parent or not.
 */
enum rbd_obj_write_state {
	RBD_OBJ_WRITE_FLAT = 1,
	RBD_OBJ_WRITE_GUARD,
	RBD_OBJ_WRITE_COPYUP,
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};

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struct rbd_obj_request {
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	struct ceph_object_extent ex;
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	union {
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		bool			tried_parent;	/* for reads */
		enum rbd_obj_write_state write_state;	/* for writes */
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	};
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	struct rbd_img_request	*img_request;
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	struct ceph_file_extent	*img_extents;
	u32			num_img_extents;
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	union {
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		struct ceph_bio_iter	bio_pos;
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		struct {
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			struct ceph_bvec_iter	bvec_pos;
			u32			bvec_count;
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			u32			bvec_idx;
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		};
	};
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	struct bio_vec		*copyup_bvecs;
	u32			copyup_bvec_count;
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	struct ceph_osd_request	*osd_req;

	u64			xferred;	/* bytes transferred */
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	int			result;
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	struct kref		kref;
};

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enum img_req_flags {
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	IMG_REQ_CHILD,		/* initiator: block = 0, child image = 1 */
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	IMG_REQ_LAYERED,	/* ENOENT handling: normal = 0, layered = 1 */
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};

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struct rbd_img_request {
	struct rbd_device	*rbd_dev;
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	enum obj_operation_type	op_type;
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	enum obj_request_type	data_type;
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	unsigned long		flags;
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	union {
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		u64			snap_id;	/* for reads */
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		struct ceph_snap_context *snapc;	/* for writes */
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	};
	union {
		struct request		*rq;		/* block request */
		struct rbd_obj_request	*obj_request;	/* obj req initiator */
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	};
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	spinlock_t		completion_lock;
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	u64			xferred;/* aggregate bytes transferred */
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	int			result;	/* first nonzero obj_request result */
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	struct list_head	object_extents;	/* obj_req.ex structs */
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	u32			obj_request_count;
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	u32			pending_count;
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	struct kref		kref;
};

#define for_each_obj_request(ireq, oreq) \
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	list_for_each_entry(oreq, &(ireq)->object_extents, ex.oe_item)
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#define for_each_obj_request_safe(ireq, oreq, n) \
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	list_for_each_entry_safe(oreq, n, &(ireq)->object_extents, ex.oe_item)
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enum rbd_watch_state {
	RBD_WATCH_STATE_UNREGISTERED,
	RBD_WATCH_STATE_REGISTERED,
	RBD_WATCH_STATE_ERROR,
};

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enum rbd_lock_state {
	RBD_LOCK_STATE_UNLOCKED,
	RBD_LOCK_STATE_LOCKED,
	RBD_LOCK_STATE_RELEASING,
};

/* WatchNotify::ClientId */
struct rbd_client_id {
	u64 gid;
	u64 handle;
};

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struct rbd_mapping {
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	u64                     size;
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	u64                     features;
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};

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/*
 * a single device
 */
struct rbd_device {
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	int			dev_id;		/* blkdev unique id */
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	int			major;		/* blkdev assigned major */
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	int			minor;
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	struct gendisk		*disk;		/* blkdev's gendisk and rq */

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	u32			image_format;	/* Either 1 or 2 */
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	struct rbd_client	*rbd_client;

	char			name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */

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	spinlock_t		lock;		/* queue, flags, open_count */
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	struct rbd_image_header	header;
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	unsigned long		flags;		/* possibly lock protected */
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	struct rbd_spec		*spec;
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	struct rbd_options	*opts;
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	char			*config_info;	/* add{,_single_major} string */
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	struct ceph_object_id	header_oid;
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	struct ceph_object_locator header_oloc;
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	struct ceph_file_layout	layout;		/* used for all rbd requests */
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	struct mutex		watch_mutex;
	enum rbd_watch_state	watch_state;
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	struct ceph_osd_linger_request *watch_handle;
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	u64			watch_cookie;
	struct delayed_work	watch_dwork;
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	struct rw_semaphore	lock_rwsem;
	enum rbd_lock_state	lock_state;
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	char			lock_cookie[32];
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	struct rbd_client_id	owner_cid;
	struct work_struct	acquired_lock_work;
	struct work_struct	released_lock_work;
	struct delayed_work	lock_dwork;
	struct work_struct	unlock_work;
	wait_queue_head_t	lock_waitq;

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	struct workqueue_struct	*task_wq;
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	struct rbd_spec		*parent_spec;
	u64			parent_overlap;
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	atomic_t		parent_ref;
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	struct rbd_device	*parent;
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	/* Block layer tags. */
	struct blk_mq_tag_set	tag_set;

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	/* protects updating the header */
	struct rw_semaphore     header_rwsem;
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	struct rbd_mapping	mapping;
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	struct list_head	node;
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	/* sysfs related */
	struct device		dev;
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	unsigned long		open_count;	/* protected by lock */
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};

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/*
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 * Flag bits for rbd_dev->flags:
 * - REMOVING (which is coupled with rbd_dev->open_count) is protected
 *   by rbd_dev->lock
 * - BLACKLISTED is protected by rbd_dev->lock_rwsem
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 */
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enum rbd_dev_flags {
	RBD_DEV_FLAG_EXISTS,	/* mapped snapshot has not been deleted */
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	RBD_DEV_FLAG_REMOVING,	/* this mapping is being removed */
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	RBD_DEV_FLAG_BLACKLISTED, /* our ceph_client is blacklisted */
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};

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static DEFINE_MUTEX(client_mutex);	/* Serialize client creation */
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static LIST_HEAD(rbd_dev_list);    /* devices */
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static DEFINE_SPINLOCK(rbd_dev_list_lock);

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static LIST_HEAD(rbd_client_list);		/* clients */
static DEFINE_SPINLOCK(rbd_client_list_lock);
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/* Slab caches for frequently-allocated structures */

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static struct kmem_cache	*rbd_img_request_cache;
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static struct kmem_cache	*rbd_obj_request_cache;
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static int rbd_major;
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static DEFINE_IDA(rbd_dev_id_ida);

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static struct workqueue_struct *rbd_wq;

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/*
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 * single-major requires >= 0.75 version of userspace rbd utility.
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 */
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static bool single_major = true;
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module_param(single_major, bool, 0444);
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MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)");
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static ssize_t rbd_add(struct bus_type *bus, const char *buf,
		       size_t count);
static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
			  size_t count);
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static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf,
				    size_t count);
static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf,
				       size_t count);
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static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth);
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static int rbd_dev_id_to_minor(int dev_id)
{
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	return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
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}

static int minor_to_rbd_dev_id(int minor)
{
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	return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
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}

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static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev)
{
	return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED ||
	       rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING;
}

static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
{
	bool is_lock_owner;

	down_read(&rbd_dev->lock_rwsem);
	is_lock_owner = __rbd_is_lock_owner(rbd_dev);
	up_read(&rbd_dev->lock_rwsem);
	return is_lock_owner;
}

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static ssize_t rbd_supported_features_show(struct bus_type *bus, char *buf)
{
	return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
}

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static BUS_ATTR(add, 0200, NULL, rbd_add);
static BUS_ATTR(remove, 0200, NULL, rbd_remove);
static BUS_ATTR(add_single_major, 0200, NULL, rbd_add_single_major);
static BUS_ATTR(remove_single_major, 0200, NULL, rbd_remove_single_major);
static BUS_ATTR(supported_features, 0444, rbd_supported_features_show, NULL);
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static struct attribute *rbd_bus_attrs[] = {
	&bus_attr_add.attr,
	&bus_attr_remove.attr,
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	&bus_attr_add_single_major.attr,
	&bus_attr_remove_single_major.attr,
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	&bus_attr_supported_features.attr,
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	NULL,
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};
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static umode_t rbd_bus_is_visible(struct kobject *kobj,
				  struct attribute *attr, int index)
{
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	if (!single_major &&
	    (attr == &bus_attr_add_single_major.attr ||
	     attr == &bus_attr_remove_single_major.attr))
		return 0;

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	return attr->mode;
}

static const struct attribute_group rbd_bus_group = {
	.attrs = rbd_bus_attrs,
	.is_visible = rbd_bus_is_visible,
};
__ATTRIBUTE_GROUPS(rbd_bus);
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static struct bus_type rbd_bus_type = {
	.name		= "rbd",
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	.bus_groups	= rbd_bus_groups,
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};

static void rbd_root_dev_release(struct device *dev)
{
}

static struct device rbd_root_dev = {
	.init_name =    "rbd",
	.release =      rbd_root_dev_release,
};

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static __printf(2, 3)
void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;

	va_start(args, fmt);
	vaf.fmt = fmt;
	vaf.va = &args;

	if (!rbd_dev)
		printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
	else if (rbd_dev->disk)
		printk(KERN_WARNING "%s: %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
	else if (rbd_dev->spec && rbd_dev->spec->image_name)
		printk(KERN_WARNING "%s: image %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
	else if (rbd_dev->spec && rbd_dev->spec->image_id)
		printk(KERN_WARNING "%s: id %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
	else	/* punt */
		printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
			RBD_DRV_NAME, rbd_dev, &vaf);
	va_end(args);
}

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#ifdef RBD_DEBUG
#define rbd_assert(expr)						\
		if (unlikely(!(expr))) {				\
			printk(KERN_ERR "\nAssertion failure in %s() "	\
						"at line %d:\n\n"	\
					"\trbd_assert(%s);\n\n",	\
					__func__, __LINE__, #expr);	\
			BUG();						\
		}
#else /* !RBD_DEBUG */
#  define rbd_assert(expr)	((void) 0)
#endif /* !RBD_DEBUG */
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static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
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static int rbd_dev_refresh(struct rbd_device *rbd_dev);
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static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
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static int rbd_dev_header_info(struct rbd_device *rbd_dev);
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static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev);
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static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id);
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static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u8 *order, u64 *snap_size);
static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
		u64 *snap_features);
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static int rbd_open(struct block_device *bdev, fmode_t mode)
{
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	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
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	bool removing = false;
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	spin_lock_irq(&rbd_dev->lock);
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	if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
		removing = true;
	else
		rbd_dev->open_count++;
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	spin_unlock_irq(&rbd_dev->lock);
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	if (removing)
		return -ENOENT;

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	(void) get_device(&rbd_dev->dev);
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	return 0;
}

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static void rbd_release(struct gendisk *disk, fmode_t mode)
590 591
{
	struct rbd_device *rbd_dev = disk->private_data;
592 593
	unsigned long open_count_before;

594
	spin_lock_irq(&rbd_dev->lock);
595
	open_count_before = rbd_dev->open_count--;
596
	spin_unlock_irq(&rbd_dev->lock);
597
	rbd_assert(open_count_before > 0);
598

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599
	put_device(&rbd_dev->dev);
600 601
}

G
Guangliang Zhao 已提交
602 603
static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
{
604
	int ro;
G
Guangliang Zhao 已提交
605

606
	if (get_user(ro, (int __user *)arg))
G
Guangliang Zhao 已提交
607 608
		return -EFAULT;

609
	/* Snapshots can't be marked read-write */
G
Guangliang Zhao 已提交
610 611 612
	if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
		return -EROFS;

613 614
	/* Let blkdev_roset() handle it */
	return -ENOTTY;
G
Guangliang Zhao 已提交
615 616 617 618 619 620
}

static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
			unsigned int cmd, unsigned long arg)
{
	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
621
	int ret;
G
Guangliang Zhao 已提交
622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641

	switch (cmd) {
	case BLKROSET:
		ret = rbd_ioctl_set_ro(rbd_dev, arg);
		break;
	default:
		ret = -ENOTTY;
	}

	return ret;
}

#ifdef CONFIG_COMPAT
static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
				unsigned int cmd, unsigned long arg)
{
	return rbd_ioctl(bdev, mode, cmd, arg);
}
#endif /* CONFIG_COMPAT */

642 643 644
static const struct block_device_operations rbd_bd_ops = {
	.owner			= THIS_MODULE,
	.open			= rbd_open,
645
	.release		= rbd_release,
G
Guangliang Zhao 已提交
646 647 648 649
	.ioctl			= rbd_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl		= rbd_compat_ioctl,
#endif
650 651 652
};

/*
653
 * Initialize an rbd client instance.  Success or not, this function
654
 * consumes ceph_opts.  Caller holds client_mutex.
655
 */
656
static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
657 658 659 660
{
	struct rbd_client *rbdc;
	int ret = -ENOMEM;

A
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661
	dout("%s:\n", __func__);
662 663 664 665 666 667 668
	rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
	if (!rbdc)
		goto out_opt;

	kref_init(&rbdc->kref);
	INIT_LIST_HEAD(&rbdc->node);

669
	rbdc->client = ceph_create_client(ceph_opts, rbdc);
670
	if (IS_ERR(rbdc->client))
671
		goto out_rbdc;
A
Alex Elder 已提交
672
	ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
673 674 675

	ret = ceph_open_session(rbdc->client);
	if (ret < 0)
676
		goto out_client;
677

A
Alex Elder 已提交
678
	spin_lock(&rbd_client_list_lock);
679
	list_add_tail(&rbdc->node, &rbd_client_list);
A
Alex Elder 已提交
680
	spin_unlock(&rbd_client_list_lock);
681

A
Alex Elder 已提交
682
	dout("%s: rbdc %p\n", __func__, rbdc);
683

684
	return rbdc;
685
out_client:
686
	ceph_destroy_client(rbdc->client);
687
out_rbdc:
688 689
	kfree(rbdc);
out_opt:
A
Alex Elder 已提交
690 691
	if (ceph_opts)
		ceph_destroy_options(ceph_opts);
A
Alex Elder 已提交
692 693
	dout("%s: error %d\n", __func__, ret);

V
Vasiliy Kulikov 已提交
694
	return ERR_PTR(ret);
695 696
}

697 698 699 700 701 702 703
static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
{
	kref_get(&rbdc->kref);

	return rbdc;
}

704
/*
705 706
 * Find a ceph client with specific addr and configuration.  If
 * found, bump its reference count.
707
 */
708
static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
709 710
{
	struct rbd_client *client_node;
711
	bool found = false;
712

A
Alex Elder 已提交
713
	if (ceph_opts->flags & CEPH_OPT_NOSHARE)
714 715
		return NULL;

716 717 718
	spin_lock(&rbd_client_list_lock);
	list_for_each_entry(client_node, &rbd_client_list, node) {
		if (!ceph_compare_options(ceph_opts, client_node->client)) {
719 720
			__rbd_get_client(client_node);

721 722 723 724 725 726 727
			found = true;
			break;
		}
	}
	spin_unlock(&rbd_client_list_lock);

	return found ? client_node : NULL;
728 729
}

730
/*
731
 * (Per device) rbd map options
732 733
 */
enum {
I
Ilya Dryomov 已提交
734
	Opt_queue_depth,
735
	Opt_lock_timeout,
736 737 738 739
	Opt_last_int,
	/* int args above */
	Opt_last_string,
	/* string args above */
A
Alex Elder 已提交
740 741
	Opt_read_only,
	Opt_read_write,
I
Ilya Dryomov 已提交
742
	Opt_lock_on_read,
I
Ilya Dryomov 已提交
743
	Opt_exclusive,
I
Ilya Dryomov 已提交
744
	Opt_notrim,
745
	Opt_err
746 747
};

A
Alex Elder 已提交
748
static match_table_t rbd_opts_tokens = {
I
Ilya Dryomov 已提交
749
	{Opt_queue_depth, "queue_depth=%d"},
750
	{Opt_lock_timeout, "lock_timeout=%d"},
751 752
	/* int args above */
	/* string args above */
A
Alex Elder 已提交
753
	{Opt_read_only, "read_only"},
A
Alex Elder 已提交
754 755 756
	{Opt_read_only, "ro"},		/* Alternate spelling */
	{Opt_read_write, "read_write"},
	{Opt_read_write, "rw"},		/* Alternate spelling */
I
Ilya Dryomov 已提交
757
	{Opt_lock_on_read, "lock_on_read"},
I
Ilya Dryomov 已提交
758
	{Opt_exclusive, "exclusive"},
I
Ilya Dryomov 已提交
759
	{Opt_notrim, "notrim"},
760
	{Opt_err, NULL}
761 762
};

A
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763
struct rbd_options {
I
Ilya Dryomov 已提交
764
	int	queue_depth;
765
	unsigned long	lock_timeout;
A
Alex Elder 已提交
766
	bool	read_only;
I
Ilya Dryomov 已提交
767
	bool	lock_on_read;
I
Ilya Dryomov 已提交
768
	bool	exclusive;
I
Ilya Dryomov 已提交
769
	bool	trim;
A
Alex Elder 已提交
770 771
};

I
Ilya Dryomov 已提交
772
#define RBD_QUEUE_DEPTH_DEFAULT	BLKDEV_MAX_RQ
773
#define RBD_LOCK_TIMEOUT_DEFAULT 0  /* no timeout */
A
Alex Elder 已提交
774
#define RBD_READ_ONLY_DEFAULT	false
I
Ilya Dryomov 已提交
775
#define RBD_LOCK_ON_READ_DEFAULT false
I
Ilya Dryomov 已提交
776
#define RBD_EXCLUSIVE_DEFAULT	false
I
Ilya Dryomov 已提交
777
#define RBD_TRIM_DEFAULT	true
A
Alex Elder 已提交
778

779 780
static int parse_rbd_opts_token(char *c, void *private)
{
A
Alex Elder 已提交
781
	struct rbd_options *rbd_opts = private;
782 783 784
	substring_t argstr[MAX_OPT_ARGS];
	int token, intval, ret;

A
Alex Elder 已提交
785
	token = match_token(c, rbd_opts_tokens, argstr);
786 787 788
	if (token < Opt_last_int) {
		ret = match_int(&argstr[0], &intval);
		if (ret < 0) {
789
			pr_err("bad mount option arg (not int) at '%s'\n", c);
790 791 792 793
			return ret;
		}
		dout("got int token %d val %d\n", token, intval);
	} else if (token > Opt_last_int && token < Opt_last_string) {
794
		dout("got string token %d val %s\n", token, argstr[0].from);
795 796 797 798 799
	} else {
		dout("got token %d\n", token);
	}

	switch (token) {
I
Ilya Dryomov 已提交
800 801 802 803 804 805 806
	case Opt_queue_depth:
		if (intval < 1) {
			pr_err("queue_depth out of range\n");
			return -EINVAL;
		}
		rbd_opts->queue_depth = intval;
		break;
807 808 809 810 811 812 813 814
	case Opt_lock_timeout:
		/* 0 is "wait forever" (i.e. infinite timeout) */
		if (intval < 0 || intval > INT_MAX / 1000) {
			pr_err("lock_timeout out of range\n");
			return -EINVAL;
		}
		rbd_opts->lock_timeout = msecs_to_jiffies(intval * 1000);
		break;
A
Alex Elder 已提交
815 816 817 818 819 820
	case Opt_read_only:
		rbd_opts->read_only = true;
		break;
	case Opt_read_write:
		rbd_opts->read_only = false;
		break;
I
Ilya Dryomov 已提交
821 822 823
	case Opt_lock_on_read:
		rbd_opts->lock_on_read = true;
		break;
I
Ilya Dryomov 已提交
824 825 826
	case Opt_exclusive:
		rbd_opts->exclusive = true;
		break;
I
Ilya Dryomov 已提交
827 828 829
	case Opt_notrim:
		rbd_opts->trim = false;
		break;
830
	default:
831 832
		/* libceph prints "bad option" msg */
		return -EINVAL;
833
	}
834

835 836 837
	return 0;
}

G
Guangliang Zhao 已提交
838 839 840 841 842 843 844
static char* obj_op_name(enum obj_operation_type op_type)
{
	switch (op_type) {
	case OBJ_OP_READ:
		return "read";
	case OBJ_OP_WRITE:
		return "write";
845 846
	case OBJ_OP_DISCARD:
		return "discard";
G
Guangliang Zhao 已提交
847 848 849 850 851
	default:
		return "???";
	}
}

852 853
/*
 * Destroy ceph client
A
Alex Elder 已提交
854
 *
A
Alex Elder 已提交
855
 * Caller must hold rbd_client_list_lock.
856 857 858 859 860
 */
static void rbd_client_release(struct kref *kref)
{
	struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);

A
Alex Elder 已提交
861
	dout("%s: rbdc %p\n", __func__, rbdc);
862
	spin_lock(&rbd_client_list_lock);
863
	list_del(&rbdc->node);
864
	spin_unlock(&rbd_client_list_lock);
865 866 867 868 869 870 871 872 873

	ceph_destroy_client(rbdc->client);
	kfree(rbdc);
}

/*
 * Drop reference to ceph client node. If it's not referenced anymore, release
 * it.
 */
874
static void rbd_put_client(struct rbd_client *rbdc)
875
{
876 877
	if (rbdc)
		kref_put(&rbdc->kref, rbd_client_release);
878 879
}

880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896
static int wait_for_latest_osdmap(struct ceph_client *client)
{
	u64 newest_epoch;
	int ret;

	ret = ceph_monc_get_version(&client->monc, "osdmap", &newest_epoch);
	if (ret)
		return ret;

	if (client->osdc.osdmap->epoch >= newest_epoch)
		return 0;

	ceph_osdc_maybe_request_map(&client->osdc);
	return ceph_monc_wait_osdmap(&client->monc, newest_epoch,
				     client->options->mount_timeout);
}

897 898 899 900 901 902 903 904
/*
 * Get a ceph client with specific addr and configuration, if one does
 * not exist create it.  Either way, ceph_opts is consumed by this
 * function.
 */
static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
{
	struct rbd_client *rbdc;
905
	int ret;
906 907 908

	mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING);
	rbdc = rbd_client_find(ceph_opts);
909
	if (rbdc) {
910
		ceph_destroy_options(ceph_opts);
911 912 913 914 915 916 917 918 919 920 921 922

		/*
		 * Using an existing client.  Make sure ->pg_pools is up to
		 * date before we look up the pool id in do_rbd_add().
		 */
		ret = wait_for_latest_osdmap(rbdc->client);
		if (ret) {
			rbd_warn(NULL, "failed to get latest osdmap: %d", ret);
			rbd_put_client(rbdc);
			rbdc = ERR_PTR(ret);
		}
	} else {
923
		rbdc = rbd_client_create(ceph_opts);
924
	}
925 926 927 928 929
	mutex_unlock(&client_mutex);

	return rbdc;
}

930 931 932 933 934
static bool rbd_image_format_valid(u32 image_format)
{
	return image_format == 1 || image_format == 2;
}

935 936
static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
{
937 938 939 940 941 942 943
	size_t size;
	u32 snap_count;

	/* The header has to start with the magic rbd header text */
	if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
		return false;

A
Alex Elder 已提交
944 945 946 947 948 949 950 951 952 953
	/* The bio layer requires at least sector-sized I/O */

	if (ondisk->options.order < SECTOR_SHIFT)
		return false;

	/* If we use u64 in a few spots we may be able to loosen this */

	if (ondisk->options.order > 8 * sizeof (int) - 1)
		return false;

954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971
	/*
	 * The size of a snapshot header has to fit in a size_t, and
	 * that limits the number of snapshots.
	 */
	snap_count = le32_to_cpu(ondisk->snap_count);
	size = SIZE_MAX - sizeof (struct ceph_snap_context);
	if (snap_count > size / sizeof (__le64))
		return false;

	/*
	 * Not only that, but the size of the entire the snapshot
	 * header must also be representable in a size_t.
	 */
	size -= snap_count * sizeof (__le64);
	if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
		return false;

	return true;
972 973
}

I
Ilya Dryomov 已提交
974 975 976 977 978 979 980 981
/*
 * returns the size of an object in the image
 */
static u32 rbd_obj_bytes(struct rbd_image_header *header)
{
	return 1U << header->obj_order;
}

I
Ilya Dryomov 已提交
982 983 984 985 986 987 988 989 990 991 992
static void rbd_init_layout(struct rbd_device *rbd_dev)
{
	if (rbd_dev->header.stripe_unit == 0 ||
	    rbd_dev->header.stripe_count == 0) {
		rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header);
		rbd_dev->header.stripe_count = 1;
	}

	rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit;
	rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count;
	rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header);
993 994
	rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ?
			  rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id;
I
Ilya Dryomov 已提交
995 996 997
	RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
}

998
/*
999 1000
 * Fill an rbd image header with information from the given format 1
 * on-disk header.
1001
 */
A
Alex Elder 已提交
1002
static int rbd_header_from_disk(struct rbd_device *rbd_dev,
1003
				 struct rbd_image_header_ondisk *ondisk)
1004
{
A
Alex Elder 已提交
1005
	struct rbd_image_header *header = &rbd_dev->header;
1006 1007 1008 1009 1010
	bool first_time = header->object_prefix == NULL;
	struct ceph_snap_context *snapc;
	char *object_prefix = NULL;
	char *snap_names = NULL;
	u64 *snap_sizes = NULL;
1011
	u32 snap_count;
1012
	int ret = -ENOMEM;
1013
	u32 i;
1014

1015
	/* Allocate this now to avoid having to handle failure below */
A
Alex Elder 已提交
1016

1017
	if (first_time) {
1018 1019 1020
		object_prefix = kstrndup(ondisk->object_prefix,
					 sizeof(ondisk->object_prefix),
					 GFP_KERNEL);
1021 1022 1023
		if (!object_prefix)
			return -ENOMEM;
	}
A
Alex Elder 已提交
1024

1025
	/* Allocate the snapshot context and fill it in */
A
Alex Elder 已提交
1026

1027 1028 1029 1030 1031
	snap_count = le32_to_cpu(ondisk->snap_count);
	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
	if (!snapc)
		goto out_err;
	snapc->seq = le64_to_cpu(ondisk->snap_seq);
1032
	if (snap_count) {
1033
		struct rbd_image_snap_ondisk *snaps;
A
Alex Elder 已提交
1034 1035
		u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);

1036
		/* We'll keep a copy of the snapshot names... */
1037

1038 1039 1040 1041
		if (snap_names_len > (u64)SIZE_MAX)
			goto out_2big;
		snap_names = kmalloc(snap_names_len, GFP_KERNEL);
		if (!snap_names)
A
Alex Elder 已提交
1042 1043
			goto out_err;

1044
		/* ...as well as the array of their sizes. */
1045 1046 1047
		snap_sizes = kmalloc_array(snap_count,
					   sizeof(*header->snap_sizes),
					   GFP_KERNEL);
1048
		if (!snap_sizes)
A
Alex Elder 已提交
1049
			goto out_err;
1050

A
Alex Elder 已提交
1051
		/*
1052 1053 1054
		 * Copy the names, and fill in each snapshot's id
		 * and size.
		 *
1055
		 * Note that rbd_dev_v1_header_info() guarantees the
1056
		 * ondisk buffer we're working with has
A
Alex Elder 已提交
1057 1058 1059
		 * snap_names_len bytes beyond the end of the
		 * snapshot id array, this memcpy() is safe.
		 */
1060 1061 1062 1063 1064 1065
		memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
		snaps = ondisk->snaps;
		for (i = 0; i < snap_count; i++) {
			snapc->snaps[i] = le64_to_cpu(snaps[i].id);
			snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
		}
1066
	}
A
Alex Elder 已提交
1067

1068
	/* We won't fail any more, fill in the header */
1069

1070 1071 1072
	if (first_time) {
		header->object_prefix = object_prefix;
		header->obj_order = ondisk->options.order;
I
Ilya Dryomov 已提交
1073
		rbd_init_layout(rbd_dev);
1074
	} else {
A
Alex Elder 已提交
1075 1076 1077
		ceph_put_snap_context(header->snapc);
		kfree(header->snap_names);
		kfree(header->snap_sizes);
1078
	}
1079

1080
	/* The remaining fields always get updated (when we refresh) */
1081

A
Alex Elder 已提交
1082
	header->image_size = le64_to_cpu(ondisk->image_size);
1083 1084 1085
	header->snapc = snapc;
	header->snap_names = snap_names;
	header->snap_sizes = snap_sizes;
1086

1087
	return 0;
1088 1089
out_2big:
	ret = -EIO;
A
Alex Elder 已提交
1090
out_err:
1091 1092 1093 1094
	kfree(snap_sizes);
	kfree(snap_names);
	ceph_put_snap_context(snapc);
	kfree(object_prefix);
1095

1096
	return ret;
1097 1098
}

1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113
static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
{
	const char *snap_name;

	rbd_assert(which < rbd_dev->header.snapc->num_snaps);

	/* Skip over names until we find the one we are looking for */

	snap_name = rbd_dev->header.snap_names;
	while (which--)
		snap_name += strlen(snap_name) + 1;

	return kstrdup(snap_name, GFP_KERNEL);
}

1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137
/*
 * Snapshot id comparison function for use with qsort()/bsearch().
 * Note that result is for snapshots in *descending* order.
 */
static int snapid_compare_reverse(const void *s1, const void *s2)
{
	u64 snap_id1 = *(u64 *)s1;
	u64 snap_id2 = *(u64 *)s2;

	if (snap_id1 < snap_id2)
		return 1;
	return snap_id1 == snap_id2 ? 0 : -1;
}

/*
 * Search a snapshot context to see if the given snapshot id is
 * present.
 *
 * Returns the position of the snapshot id in the array if it's found,
 * or BAD_SNAP_INDEX otherwise.
 *
 * Note: The snapshot array is in kept sorted (by the osd) in
 * reverse order, highest snapshot id first.
 */
1138 1139 1140
static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1141
	u64 *found;
1142

1143 1144
	found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
				sizeof (snap_id), snapid_compare_reverse);
1145

1146
	return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1147 1148
}

1149 1150
static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id)
1151
{
1152
	u32 which;
1153
	const char *snap_name;
1154

1155 1156
	which = rbd_dev_snap_index(rbd_dev, snap_id);
	if (which == BAD_SNAP_INDEX)
1157
		return ERR_PTR(-ENOENT);
1158

1159 1160
	snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
	return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1161 1162 1163 1164
}

static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
{
1165 1166 1167
	if (snap_id == CEPH_NOSNAP)
		return RBD_SNAP_HEAD_NAME;

1168 1169 1170
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (rbd_dev->image_format == 1)
		return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1171

1172
	return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1173 1174
}

1175 1176
static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u64 *snap_size)
1177
{
1178 1179 1180 1181 1182
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (snap_id == CEPH_NOSNAP) {
		*snap_size = rbd_dev->header.image_size;
	} else if (rbd_dev->image_format == 1) {
		u32 which;
1183

1184 1185 1186
		which = rbd_dev_snap_index(rbd_dev, snap_id);
		if (which == BAD_SNAP_INDEX)
			return -ENOENT;
1187

1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
		*snap_size = rbd_dev->header.snap_sizes[which];
	} else {
		u64 size = 0;
		int ret;

		ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
		if (ret)
			return ret;

		*snap_size = size;
	}
	return 0;
1200 1201
}

1202 1203
static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
			u64 *snap_features)
1204
{
1205 1206 1207 1208 1209
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (snap_id == CEPH_NOSNAP) {
		*snap_features = rbd_dev->header.features;
	} else if (rbd_dev->image_format == 1) {
		*snap_features = 0;	/* No features for format 1 */
1210
	} else {
1211 1212
		u64 features = 0;
		int ret;
1213

1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224
		ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
		if (ret)
			return ret;

		*snap_features = features;
	}
	return 0;
}

static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
{
1225
	u64 snap_id = rbd_dev->spec->snap_id;
1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239
	u64 size = 0;
	u64 features = 0;
	int ret;

	ret = rbd_snap_size(rbd_dev, snap_id, &size);
	if (ret)
		return ret;
	ret = rbd_snap_features(rbd_dev, snap_id, &features);
	if (ret)
		return ret;

	rbd_dev->mapping.size = size;
	rbd_dev->mapping.features = features;

1240
	return 0;
1241 1242
}

A
Alex Elder 已提交
1243 1244 1245 1246
static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
{
	rbd_dev->mapping.size = 0;
	rbd_dev->mapping.features = 0;
1247 1248
}

1249
static void zero_bvec(struct bio_vec *bv)
1250 1251
{
	void *buf;
1252
	unsigned long flags;
1253

1254 1255 1256 1257
	buf = bvec_kmap_irq(bv, &flags);
	memset(buf, 0, bv->bv_len);
	flush_dcache_page(bv->bv_page);
	bvec_kunmap_irq(buf, &flags);
1258 1259
}

1260
static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
A
Alex Elder 已提交
1261
{
1262
	struct ceph_bio_iter it = *bio_pos;
A
Alex Elder 已提交
1263

1264 1265 1266 1267
	ceph_bio_iter_advance(&it, off);
	ceph_bio_iter_advance_step(&it, bytes, ({
		zero_bvec(&bv);
	}));
A
Alex Elder 已提交
1268 1269
}

1270
static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
1271
{
1272
	struct ceph_bvec_iter it = *bvec_pos;
1273

1274 1275 1276 1277
	ceph_bvec_iter_advance(&it, off);
	ceph_bvec_iter_advance_step(&it, bytes, ({
		zero_bvec(&bv);
	}));
A
Alex Elder 已提交
1278 1279 1280
}

/*
I
Ilya Dryomov 已提交
1281
 * Zero a range in @obj_req data buffer defined by a bio (list) or
1282
 * (private) bio_vec array.
A
Alex Elder 已提交
1283
 *
I
Ilya Dryomov 已提交
1284
 * @off is relative to the start of the data buffer.
1285
 */
I
Ilya Dryomov 已提交
1286 1287
static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off,
			       u32 bytes)
1288
{
1289
	switch (obj_req->img_request->data_type) {
I
Ilya Dryomov 已提交
1290 1291 1292 1293
	case OBJ_REQUEST_BIO:
		zero_bios(&obj_req->bio_pos, off, bytes);
		break;
	case OBJ_REQUEST_BVECS:
1294
	case OBJ_REQUEST_OWN_BVECS:
I
Ilya Dryomov 已提交
1295 1296 1297 1298
		zero_bvecs(&obj_req->bvec_pos, off, bytes);
		break;
	default:
		rbd_assert(0);
1299 1300 1301
	}
}

A
Alex Elder 已提交
1302 1303 1304 1305
static void rbd_obj_request_destroy(struct kref *kref);
static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
{
	rbd_assert(obj_request != NULL);
A
Alex Elder 已提交
1306
	dout("%s: obj %p (was %d)\n", __func__, obj_request,
1307
		kref_read(&obj_request->kref));
A
Alex Elder 已提交
1308 1309 1310
	kref_put(&obj_request->kref, rbd_obj_request_destroy);
}

1311 1312 1313
static void rbd_img_request_get(struct rbd_img_request *img_request)
{
	dout("%s: img %p (was %d)\n", __func__, img_request,
1314
	     kref_read(&img_request->kref));
1315 1316 1317
	kref_get(&img_request->kref);
}

A
Alex Elder 已提交
1318 1319 1320 1321
static void rbd_img_request_destroy(struct kref *kref);
static void rbd_img_request_put(struct rbd_img_request *img_request)
{
	rbd_assert(img_request != NULL);
A
Alex Elder 已提交
1322
	dout("%s: img %p (was %d)\n", __func__, img_request,
1323
		kref_read(&img_request->kref));
1324
	kref_put(&img_request->kref, rbd_img_request_destroy);
A
Alex Elder 已提交
1325 1326 1327 1328 1329
}

static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
					struct rbd_obj_request *obj_request)
{
1330 1331
	rbd_assert(obj_request->img_request == NULL);

1332
	/* Image request now owns object's original reference */
A
Alex Elder 已提交
1333
	obj_request->img_request = img_request;
1334
	img_request->obj_request_count++;
I
Ilya Dryomov 已提交
1335
	img_request->pending_count++;
1336
	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
A
Alex Elder 已提交
1337 1338 1339 1340 1341
}

static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
					struct rbd_obj_request *obj_request)
{
1342
	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1343
	list_del(&obj_request->ex.oe_item);
1344 1345
	rbd_assert(img_request->obj_request_count > 0);
	img_request->obj_request_count--;
A
Alex Elder 已提交
1346 1347 1348 1349
	rbd_assert(obj_request->img_request == img_request);
	rbd_obj_request_put(obj_request);
}

1350
static void rbd_obj_request_submit(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1351
{
1352 1353
	struct ceph_osd_request *osd_req = obj_request->osd_req;

1354
	dout("%s %p object_no %016llx %llu~%llu osd_req %p\n", __func__,
1355 1356
	     obj_request, obj_request->ex.oe_objno, obj_request->ex.oe_off,
	     obj_request->ex.oe_len, osd_req);
1357
	ceph_osdc_start_request(osd_req->r_osdc, osd_req, false);
A
Alex Elder 已提交
1358 1359
}

A
Alex Elder 已提交
1360 1361 1362 1363 1364
/*
 * The default/initial value for all image request flags is 0.  Each
 * is conditionally set to 1 at image request initialization time
 * and currently never change thereafter.
 */
1365 1366 1367 1368 1369 1370
static void img_request_layered_set(struct rbd_img_request *img_request)
{
	set_bit(IMG_REQ_LAYERED, &img_request->flags);
	smp_mb();
}

1371 1372 1373 1374 1375 1376
static void img_request_layered_clear(struct rbd_img_request *img_request)
{
	clear_bit(IMG_REQ_LAYERED, &img_request->flags);
	smp_mb();
}

1377 1378 1379 1380 1381 1382
static bool img_request_layered_test(struct rbd_img_request *img_request)
{
	smp_mb();
	return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
}

I
Ilya Dryomov 已提交
1383
static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req)
1384
{
I
Ilya Dryomov 已提交
1385
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
A
Alex Elder 已提交
1386

1387 1388
	return !obj_req->ex.oe_off &&
	       obj_req->ex.oe_len == rbd_dev->layout.object_size;
1389 1390
}

I
Ilya Dryomov 已提交
1391
static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req)
A
Alex Elder 已提交
1392
{
I
Ilya Dryomov 已提交
1393
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
A
Alex Elder 已提交
1394

1395
	return obj_req->ex.oe_off + obj_req->ex.oe_len ==
I
Ilya Dryomov 已提交
1396
					rbd_dev->layout.object_size;
1397 1398
}

I
Ilya Dryomov 已提交
1399
static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req)
A
Alex Elder 已提交
1400
{
I
Ilya Dryomov 已提交
1401 1402
	return ceph_file_extents_bytes(obj_req->img_extents,
				       obj_req->num_img_extents);
A
Alex Elder 已提交
1403 1404
}

I
Ilya Dryomov 已提交
1405
static bool rbd_img_is_write(struct rbd_img_request *img_req)
A
Alex Elder 已提交
1406
{
I
Ilya Dryomov 已提交
1407
	switch (img_req->op_type) {
I
Ilya Dryomov 已提交
1408 1409 1410 1411 1412 1413
	case OBJ_OP_READ:
		return false;
	case OBJ_OP_WRITE:
	case OBJ_OP_DISCARD:
		return true;
	default:
A
Arnd Bergmann 已提交
1414
		BUG();
I
Ilya Dryomov 已提交
1415
	}
1416 1417
}

I
Ilya Dryomov 已提交
1418
static void rbd_obj_handle_request(struct rbd_obj_request *obj_req);
I
Ilya Dryomov 已提交
1419

1420
static void rbd_osd_req_callback(struct ceph_osd_request *osd_req)
A
Alex Elder 已提交
1421
{
I
Ilya Dryomov 已提交
1422
	struct rbd_obj_request *obj_req = osd_req->r_priv;
A
Alex Elder 已提交
1423

I
Ilya Dryomov 已提交
1424 1425 1426
	dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
	     osd_req->r_result, obj_req);
	rbd_assert(osd_req == obj_req->osd_req);
A
Alex Elder 已提交
1427

I
Ilya Dryomov 已提交
1428 1429 1430 1431 1432 1433 1434 1435 1436 1437
	obj_req->result = osd_req->r_result < 0 ? osd_req->r_result : 0;
	if (!obj_req->result && !rbd_img_is_write(obj_req->img_request))
		obj_req->xferred = osd_req->r_result;
	else
		/*
		 * Writes aren't allowed to return a data payload.  In some
		 * guarded write cases (e.g. stat + zero on an empty object)
		 * a stat response makes it through, but we don't care.
		 */
		obj_req->xferred = 0;
A
Alex Elder 已提交
1438

I
Ilya Dryomov 已提交
1439
	rbd_obj_handle_request(obj_req);
A
Alex Elder 已提交
1440 1441
}

1442
static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1443
{
1444
	struct ceph_osd_request *osd_req = obj_request->osd_req;
A
Alex Elder 已提交
1445

1446
	osd_req->r_flags = CEPH_OSD_FLAG_READ;
1447
	osd_req->r_snapid = obj_request->img_request->snap_id;
1448 1449 1450 1451 1452 1453
}

static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
{
	struct ceph_osd_request *osd_req = obj_request->osd_req;

1454
	osd_req->r_flags = CEPH_OSD_FLAG_WRITE;
1455
	ktime_get_real_ts(&osd_req->r_mtime);
1456
	osd_req->r_data_offset = obj_request->ex.oe_off;
A
Alex Elder 已提交
1457 1458
}

1459
static struct ceph_osd_request *
1460
rbd_osd_req_create(struct rbd_obj_request *obj_req, unsigned int num_ops)
1461
{
1462 1463
	struct rbd_img_request *img_req = obj_req->img_request;
	struct rbd_device *rbd_dev = img_req->rbd_dev;
1464 1465
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_osd_request *req;
1466 1467
	const char *name_format = rbd_dev->image_format == 1 ?
				      RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT;
1468

1469 1470 1471
	req = ceph_osdc_alloc_request(osdc,
			(rbd_img_is_write(img_req) ? img_req->snapc : NULL),
			num_ops, false, GFP_NOIO);
1472 1473 1474 1475
	if (!req)
		return NULL;

	req->r_callback = rbd_osd_req_callback;
1476
	req->r_priv = obj_req;
1477 1478

	req->r_base_oloc.pool = rbd_dev->layout.pool_id;
1479
	if (ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format,
1480
			rbd_dev->header.object_prefix, obj_req->ex.oe_objno))
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492
		goto err_req;

	if (ceph_osdc_alloc_messages(req, GFP_NOIO))
		goto err_req;

	return req;

err_req:
	ceph_osdc_put_request(req);
	return NULL;
}

A
Alex Elder 已提交
1493 1494 1495 1496 1497
static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
{
	ceph_osdc_put_request(osd_req);
}

1498
static struct rbd_obj_request *rbd_obj_request_create(void)
A
Alex Elder 已提交
1499 1500 1501
{
	struct rbd_obj_request *obj_request;

1502
	obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
1503
	if (!obj_request)
1504 1505
		return NULL;

1506
	ceph_object_extent_init(&obj_request->ex);
A
Alex Elder 已提交
1507 1508
	kref_init(&obj_request->kref);

1509
	dout("%s %p\n", __func__, obj_request);
A
Alex Elder 已提交
1510 1511 1512 1513 1514 1515
	return obj_request;
}

static void rbd_obj_request_destroy(struct kref *kref)
{
	struct rbd_obj_request *obj_request;
1516
	u32 i;
A
Alex Elder 已提交
1517 1518 1519

	obj_request = container_of(kref, struct rbd_obj_request, kref);

A
Alex Elder 已提交
1520 1521
	dout("%s: obj %p\n", __func__, obj_request);

A
Alex Elder 已提交
1522 1523 1524
	if (obj_request->osd_req)
		rbd_osd_req_destroy(obj_request->osd_req);

1525
	switch (obj_request->img_request->data_type) {
1526
	case OBJ_REQUEST_NODATA:
A
Alex Elder 已提交
1527
	case OBJ_REQUEST_BIO:
1528
	case OBJ_REQUEST_BVECS:
1529
		break;		/* Nothing to do */
1530 1531
	case OBJ_REQUEST_OWN_BVECS:
		kfree(obj_request->bvec_pos.bvecs);
1532
		break;
1533 1534
	default:
		rbd_assert(0);
A
Alex Elder 已提交
1535 1536
	}

I
Ilya Dryomov 已提交
1537
	kfree(obj_request->img_extents);
1538 1539 1540 1541 1542 1543
	if (obj_request->copyup_bvecs) {
		for (i = 0; i < obj_request->copyup_bvec_count; i++) {
			if (obj_request->copyup_bvecs[i].bv_page)
				__free_page(obj_request->copyup_bvecs[i].bv_page);
		}
		kfree(obj_request->copyup_bvecs);
A
Alex Elder 已提交
1544 1545
	}

1546
	kmem_cache_free(rbd_obj_request_cache, obj_request);
A
Alex Elder 已提交
1547 1548
}

A
Alex Elder 已提交
1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559
/* It's OK to call this for a device with no parent */

static void rbd_spec_put(struct rbd_spec *spec);
static void rbd_dev_unparent(struct rbd_device *rbd_dev)
{
	rbd_dev_remove_parent(rbd_dev);
	rbd_spec_put(rbd_dev->parent_spec);
	rbd_dev->parent_spec = NULL;
	rbd_dev->parent_overlap = 0;
}

1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581
/*
 * Parent image reference counting is used to determine when an
 * image's parent fields can be safely torn down--after there are no
 * more in-flight requests to the parent image.  When the last
 * reference is dropped, cleaning them up is safe.
 */
static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
{
	int counter;

	if (!rbd_dev->parent_spec)
		return;

	counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
	if (counter > 0)
		return;

	/* Last reference; clean up parent data structures */

	if (!counter)
		rbd_dev_unparent(rbd_dev);
	else
1582
		rbd_warn(rbd_dev, "parent reference underflow");
1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594
}

/*
 * If an image has a non-zero parent overlap, get a reference to its
 * parent.
 *
 * Returns true if the rbd device has a parent with a non-zero
 * overlap and a reference for it was successfully taken, or
 * false otherwise.
 */
static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
{
1595
	int counter = 0;
1596 1597 1598 1599

	if (!rbd_dev->parent_spec)
		return false;

1600 1601 1602 1603
	down_read(&rbd_dev->header_rwsem);
	if (rbd_dev->parent_overlap)
		counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
	up_read(&rbd_dev->header_rwsem);
1604 1605

	if (counter < 0)
1606
		rbd_warn(rbd_dev, "parent reference overflow");
1607

1608
	return counter > 0;
1609 1610
}

A
Alex Elder 已提交
1611 1612 1613 1614 1615
/*
 * Caller is responsible for filling in the list of object requests
 * that comprises the image request, and the Linux request pointer
 * (if there is one).
 */
A
Alex Elder 已提交
1616 1617
static struct rbd_img_request *rbd_img_request_create(
					struct rbd_device *rbd_dev,
G
Guangliang Zhao 已提交
1618
					enum obj_operation_type op_type,
1619
					struct ceph_snap_context *snapc)
A
Alex Elder 已提交
1620 1621 1622
{
	struct rbd_img_request *img_request;

1623
	img_request = kmem_cache_zalloc(rbd_img_request_cache, GFP_NOIO);
A
Alex Elder 已提交
1624 1625 1626 1627
	if (!img_request)
		return NULL;

	img_request->rbd_dev = rbd_dev;
I
Ilya Dryomov 已提交
1628 1629
	img_request->op_type = op_type;
	if (!rbd_img_is_write(img_request))
A
Alex Elder 已提交
1630
		img_request->snap_id = rbd_dev->spec->snap_id;
I
Ilya Dryomov 已提交
1631 1632 1633
	else
		img_request->snapc = snapc;

1634
	if (rbd_dev_parent_get(rbd_dev))
1635
		img_request_layered_set(img_request);
1636

A
Alex Elder 已提交
1637
	spin_lock_init(&img_request->completion_lock);
1638
	INIT_LIST_HEAD(&img_request->object_extents);
A
Alex Elder 已提交
1639 1640
	kref_init(&img_request->kref);

1641 1642
	dout("%s: rbd_dev %p %s -> img %p\n", __func__, rbd_dev,
	     obj_op_name(op_type), img_request);
A
Alex Elder 已提交
1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653
	return img_request;
}

static void rbd_img_request_destroy(struct kref *kref)
{
	struct rbd_img_request *img_request;
	struct rbd_obj_request *obj_request;
	struct rbd_obj_request *next_obj_request;

	img_request = container_of(kref, struct rbd_img_request, kref);

A
Alex Elder 已提交
1654 1655
	dout("%s: img %p\n", __func__, img_request);

A
Alex Elder 已提交
1656 1657
	for_each_obj_request_safe(img_request, obj_request, next_obj_request)
		rbd_img_obj_request_del(img_request, obj_request);
1658
	rbd_assert(img_request->obj_request_count == 0);
A
Alex Elder 已提交
1659

1660 1661 1662 1663 1664
	if (img_request_layered_test(img_request)) {
		img_request_layered_clear(img_request);
		rbd_dev_parent_put(img_request->rbd_dev);
	}

I
Ilya Dryomov 已提交
1665
	if (rbd_img_is_write(img_request))
1666
		ceph_put_snap_context(img_request->snapc);
A
Alex Elder 已提交
1667

1668
	kmem_cache_free(rbd_img_request_cache, img_request);
A
Alex Elder 已提交
1669 1670
}

I
Ilya Dryomov 已提交
1671 1672
static void prune_extents(struct ceph_file_extent *img_extents,
			  u32 *num_img_extents, u64 overlap)
1673
{
I
Ilya Dryomov 已提交
1674
	u32 cnt = *num_img_extents;
1675

I
Ilya Dryomov 已提交
1676 1677 1678
	/* drop extents completely beyond the overlap */
	while (cnt && img_extents[cnt - 1].fe_off >= overlap)
		cnt--;
1679

I
Ilya Dryomov 已提交
1680 1681
	if (cnt) {
		struct ceph_file_extent *ex = &img_extents[cnt - 1];
1682

I
Ilya Dryomov 已提交
1683 1684 1685 1686
		/* trim final overlapping extent */
		if (ex->fe_off + ex->fe_len > overlap)
			ex->fe_len = overlap - ex->fe_off;
	}
1687

I
Ilya Dryomov 已提交
1688
	*num_img_extents = cnt;
1689 1690
}

I
Ilya Dryomov 已提交
1691 1692 1693 1694 1695 1696
/*
 * Determine the byte range(s) covered by either just the object extent
 * or the entire object in the parent image.
 */
static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req,
				    bool entire)
1697
{
I
Ilya Dryomov 已提交
1698 1699
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
	int ret;
1700

I
Ilya Dryomov 已提交
1701 1702
	if (!rbd_dev->parent_overlap)
		return 0;
1703

I
Ilya Dryomov 已提交
1704 1705 1706 1707 1708 1709 1710 1711
	ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno,
				  entire ? 0 : obj_req->ex.oe_off,
				  entire ? rbd_dev->layout.object_size :
							obj_req->ex.oe_len,
				  &obj_req->img_extents,
				  &obj_req->num_img_extents);
	if (ret)
		return ret;
1712

I
Ilya Dryomov 已提交
1713 1714 1715
	prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
		      rbd_dev->parent_overlap);
	return 0;
1716 1717
}

I
Ilya Dryomov 已提交
1718
static void rbd_osd_req_setup_data(struct rbd_obj_request *obj_req, u32 which)
1719
{
1720
	switch (obj_req->img_request->data_type) {
I
Ilya Dryomov 已提交
1721 1722 1723
	case OBJ_REQUEST_BIO:
		osd_req_op_extent_osd_data_bio(obj_req->osd_req, which,
					       &obj_req->bio_pos,
1724
					       obj_req->ex.oe_len);
I
Ilya Dryomov 已提交
1725 1726
		break;
	case OBJ_REQUEST_BVECS:
1727
	case OBJ_REQUEST_OWN_BVECS:
I
Ilya Dryomov 已提交
1728
		rbd_assert(obj_req->bvec_pos.iter.bi_size ==
1729
							obj_req->ex.oe_len);
1730
		rbd_assert(obj_req->bvec_idx == obj_req->bvec_count);
I
Ilya Dryomov 已提交
1731 1732 1733 1734 1735
		osd_req_op_extent_osd_data_bvec_pos(obj_req->osd_req, which,
						    &obj_req->bvec_pos);
		break;
	default:
		rbd_assert(0);
1736
	}
I
Ilya Dryomov 已提交
1737
}
1738

I
Ilya Dryomov 已提交
1739 1740
static int rbd_obj_setup_read(struct rbd_obj_request *obj_req)
{
1741
	obj_req->osd_req = rbd_osd_req_create(obj_req, 1);
I
Ilya Dryomov 已提交
1742 1743
	if (!obj_req->osd_req)
		return -ENOMEM;
1744

I
Ilya Dryomov 已提交
1745
	osd_req_op_extent_init(obj_req->osd_req, 0, CEPH_OSD_OP_READ,
1746
			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
I
Ilya Dryomov 已提交
1747
	rbd_osd_req_setup_data(obj_req, 0);
C
Christoph Hellwig 已提交
1748

I
Ilya Dryomov 已提交
1749 1750 1751 1752 1753 1754 1755 1756
	rbd_osd_req_format_read(obj_req);
	return 0;
}

static int __rbd_obj_setup_stat(struct rbd_obj_request *obj_req,
				unsigned int which)
{
	struct page **pages;
A
Alex Elder 已提交
1757

I
Ilya Dryomov 已提交
1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774
	/*
	 * The response data for a STAT call consists of:
	 *     le64 length;
	 *     struct {
	 *         le32 tv_sec;
	 *         le32 tv_nsec;
	 *     } mtime;
	 */
	pages = ceph_alloc_page_vector(1, GFP_NOIO);
	if (IS_ERR(pages))
		return PTR_ERR(pages);

	osd_req_op_init(obj_req->osd_req, which, CEPH_OSD_OP_STAT, 0);
	osd_req_op_raw_data_in_pages(obj_req->osd_req, which, pages,
				     8 + sizeof(struct ceph_timespec),
				     0, false, true);
	return 0;
1775 1776
}

I
Ilya Dryomov 已提交
1777 1778
static void __rbd_obj_setup_write(struct rbd_obj_request *obj_req,
				  unsigned int which)
1779
{
I
Ilya Dryomov 已提交
1780 1781
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
	u16 opcode;
1782

I
Ilya Dryomov 已提交
1783 1784 1785
	osd_req_op_alloc_hint_init(obj_req->osd_req, which++,
				   rbd_dev->layout.object_size,
				   rbd_dev->layout.object_size);
1786

I
Ilya Dryomov 已提交
1787 1788 1789 1790
	if (rbd_obj_is_entire(obj_req))
		opcode = CEPH_OSD_OP_WRITEFULL;
	else
		opcode = CEPH_OSD_OP_WRITE;
1791

I
Ilya Dryomov 已提交
1792
	osd_req_op_extent_init(obj_req->osd_req, which, opcode,
1793
			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
I
Ilya Dryomov 已提交
1794
	rbd_osd_req_setup_data(obj_req, which++);
1795

I
Ilya Dryomov 已提交
1796 1797 1798
	rbd_assert(which == obj_req->osd_req->r_num_ops);
	rbd_osd_req_format_write(obj_req);
}
1799

I
Ilya Dryomov 已提交
1800 1801 1802 1803 1804
static int rbd_obj_setup_write(struct rbd_obj_request *obj_req)
{
	unsigned int num_osd_ops, which = 0;
	int ret;

I
Ilya Dryomov 已提交
1805 1806 1807 1808 1809 1810
	/* reverse map the entire object onto the parent */
	ret = rbd_obj_calc_img_extents(obj_req, true);
	if (ret)
		return ret;

	if (obj_req->num_img_extents) {
I
Ilya Dryomov 已提交
1811 1812 1813 1814 1815
		obj_req->write_state = RBD_OBJ_WRITE_GUARD;
		num_osd_ops = 3; /* stat + setallochint + write/writefull */
	} else {
		obj_req->write_state = RBD_OBJ_WRITE_FLAT;
		num_osd_ops = 2; /* setallochint + write/writefull */
1816 1817
	}

1818
	obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops);
I
Ilya Dryomov 已提交
1819 1820
	if (!obj_req->osd_req)
		return -ENOMEM;
1821

I
Ilya Dryomov 已提交
1822
	if (obj_req->num_img_extents) {
I
Ilya Dryomov 已提交
1823 1824 1825 1826 1827 1828 1829
		ret = __rbd_obj_setup_stat(obj_req, which++);
		if (ret)
			return ret;
	}

	__rbd_obj_setup_write(obj_req, which);
	return 0;
1830 1831
}

I
Ilya Dryomov 已提交
1832 1833 1834
static void __rbd_obj_setup_discard(struct rbd_obj_request *obj_req,
				    unsigned int which)
{
1835 1836
	u16 opcode;

I
Ilya Dryomov 已提交
1837
	if (rbd_obj_is_entire(obj_req)) {
I
Ilya Dryomov 已提交
1838
		if (obj_req->num_img_extents) {
1839 1840
			osd_req_op_init(obj_req->osd_req, which++,
					CEPH_OSD_OP_CREATE, 0);
1841 1842
			opcode = CEPH_OSD_OP_TRUNCATE;
		} else {
I
Ilya Dryomov 已提交
1843 1844 1845
			osd_req_op_init(obj_req->osd_req, which++,
					CEPH_OSD_OP_DELETE, 0);
			opcode = 0;
1846
		}
I
Ilya Dryomov 已提交
1847 1848
	} else if (rbd_obj_is_tail(obj_req)) {
		opcode = CEPH_OSD_OP_TRUNCATE;
1849
	} else {
I
Ilya Dryomov 已提交
1850
		opcode = CEPH_OSD_OP_ZERO;
1851 1852
	}

I
Ilya Dryomov 已提交
1853 1854
	if (opcode)
		osd_req_op_extent_init(obj_req->osd_req, which++, opcode,
1855
				       obj_req->ex.oe_off, obj_req->ex.oe_len,
I
Ilya Dryomov 已提交
1856 1857 1858 1859
				       0, 0);

	rbd_assert(which == obj_req->osd_req->r_num_ops);
	rbd_osd_req_format_write(obj_req);
1860 1861
}

I
Ilya Dryomov 已提交
1862
static int rbd_obj_setup_discard(struct rbd_obj_request *obj_req)
A
Alex Elder 已提交
1863
{
I
Ilya Dryomov 已提交
1864 1865
	unsigned int num_osd_ops, which = 0;
	int ret;
A
Alex Elder 已提交
1866

I
Ilya Dryomov 已提交
1867 1868 1869 1870
	/* reverse map the entire object onto the parent */
	ret = rbd_obj_calc_img_extents(obj_req, true);
	if (ret)
		return ret;
1871

I
Ilya Dryomov 已提交
1872 1873
	if (rbd_obj_is_entire(obj_req)) {
		obj_req->write_state = RBD_OBJ_WRITE_FLAT;
1874 1875 1876 1877
		if (obj_req->num_img_extents)
			num_osd_ops = 2; /* create + truncate */
		else
			num_osd_ops = 1; /* delete */
I
Ilya Dryomov 已提交
1878
	} else {
I
Ilya Dryomov 已提交
1879
		if (obj_req->num_img_extents) {
I
Ilya Dryomov 已提交
1880 1881 1882 1883 1884 1885
			obj_req->write_state = RBD_OBJ_WRITE_GUARD;
			num_osd_ops = 2; /* stat + truncate/zero */
		} else {
			obj_req->write_state = RBD_OBJ_WRITE_FLAT;
			num_osd_ops = 1; /* truncate/zero */
		}
1886 1887
	}

1888
	obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops);
I
Ilya Dryomov 已提交
1889 1890
	if (!obj_req->osd_req)
		return -ENOMEM;
A
Alex Elder 已提交
1891

I
Ilya Dryomov 已提交
1892
	if (!rbd_obj_is_entire(obj_req) && obj_req->num_img_extents) {
I
Ilya Dryomov 已提交
1893 1894 1895 1896
		ret = __rbd_obj_setup_stat(obj_req, which++);
		if (ret)
			return ret;
	}
1897

I
Ilya Dryomov 已提交
1898 1899 1900
	__rbd_obj_setup_discard(obj_req, which);
	return 0;
}
1901

I
Ilya Dryomov 已提交
1902 1903 1904 1905 1906 1907 1908 1909 1910
/*
 * For each object request in @img_req, allocate an OSD request, add
 * individual OSD ops and prepare them for submission.  The number of
 * OSD ops depends on op_type and the overlap point (if any).
 */
static int __rbd_img_fill_request(struct rbd_img_request *img_req)
{
	struct rbd_obj_request *obj_req;
	int ret;
A
Alex Elder 已提交
1911

I
Ilya Dryomov 已提交
1912
	for_each_obj_request(img_req, obj_req) {
I
Ilya Dryomov 已提交
1913
		switch (img_req->op_type) {
I
Ilya Dryomov 已提交
1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927
		case OBJ_OP_READ:
			ret = rbd_obj_setup_read(obj_req);
			break;
		case OBJ_OP_WRITE:
			ret = rbd_obj_setup_write(obj_req);
			break;
		case OBJ_OP_DISCARD:
			ret = rbd_obj_setup_discard(obj_req);
			break;
		default:
			rbd_assert(0);
		}
		if (ret)
			return ret;
A
Alex Elder 已提交
1928 1929 1930
	}

	return 0;
I
Ilya Dryomov 已提交
1931
}
A
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1932

1933 1934 1935 1936
union rbd_img_fill_iter {
	struct ceph_bio_iter	bio_iter;
	struct ceph_bvec_iter	bvec_iter;
};
A
Alex Elder 已提交
1937

1938 1939 1940 1941 1942
struct rbd_img_fill_ctx {
	enum obj_request_type	pos_type;
	union rbd_img_fill_iter	*pos;
	union rbd_img_fill_iter	iter;
	ceph_object_extent_fn_t	set_pos_fn;
1943 1944
	ceph_object_extent_fn_t	count_fn;
	ceph_object_extent_fn_t	copy_fn;
1945
};
A
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1946

1947
static struct ceph_object_extent *alloc_object_extent(void *arg)
1948
{
1949 1950
	struct rbd_img_request *img_req = arg;
	struct rbd_obj_request *obj_req;
1951

1952 1953 1954
	obj_req = rbd_obj_request_create();
	if (!obj_req)
		return NULL;
I
Ilya Dryomov 已提交
1955

1956 1957 1958
	rbd_img_obj_request_add(img_req, obj_req);
	return &obj_req->ex;
}
1959

1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970
/*
 * While su != os && sc == 1 is technically not fancy (it's the same
 * layout as su == os && sc == 1), we can't use the nocopy path for it
 * because ->set_pos_fn() should be called only once per object.
 * ceph_file_to_extents() invokes action_fn once per stripe unit, so
 * treat su != os && sc == 1 as fancy.
 */
static bool rbd_layout_is_fancy(struct ceph_file_layout *l)
{
	return l->stripe_unit != l->object_size;
}
1971

1972 1973 1974 1975 1976 1977 1978 1979 1980
static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req,
				       struct ceph_file_extent *img_extents,
				       u32 num_img_extents,
				       struct rbd_img_fill_ctx *fctx)
{
	u32 i;
	int ret;

	img_req->data_type = fctx->pos_type;
1981 1982

	/*
1983 1984
	 * Create object requests and set each object request's starting
	 * position in the provided bio (list) or bio_vec array.
1985
	 */
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996
	fctx->iter = *fctx->pos;
	for (i = 0; i < num_img_extents; i++) {
		ret = ceph_file_to_extents(&img_req->rbd_dev->layout,
					   img_extents[i].fe_off,
					   img_extents[i].fe_len,
					   &img_req->object_extents,
					   alloc_object_extent, img_req,
					   fctx->set_pos_fn, &fctx->iter);
		if (ret)
			return ret;
	}
1997

1998
	return __rbd_img_fill_request(img_req);
1999 2000
}

2001 2002 2003 2004
/*
 * Map a list of image extents to a list of object extents, create the
 * corresponding object requests (normally each to a different object,
 * but not always) and add them to @img_req.  For each object request,
2005
 * set up its data descriptor to point to the corresponding chunk(s) of
2006 2007
 * @fctx->pos data buffer.
 *
2008 2009 2010 2011
 * Because ceph_file_to_extents() will merge adjacent object extents
 * together, each object request's data descriptor may point to multiple
 * different chunks of @fctx->pos data buffer.
 *
2012 2013 2014 2015 2016 2017
 * @fctx->pos data buffer is assumed to be large enough.
 */
static int rbd_img_fill_request(struct rbd_img_request *img_req,
				struct ceph_file_extent *img_extents,
				u32 num_img_extents,
				struct rbd_img_fill_ctx *fctx)
2018
{
2019 2020
	struct rbd_device *rbd_dev = img_req->rbd_dev;
	struct rbd_obj_request *obj_req;
2021 2022 2023
	u32 i;
	int ret;

2024 2025 2026 2027
	if (fctx->pos_type == OBJ_REQUEST_NODATA ||
	    !rbd_layout_is_fancy(&rbd_dev->layout))
		return rbd_img_fill_request_nocopy(img_req, img_extents,
						   num_img_extents, fctx);
2028

2029
	img_req->data_type = OBJ_REQUEST_OWN_BVECS;
2030

2031
	/*
2032 2033 2034 2035 2036
	 * Create object requests and determine ->bvec_count for each object
	 * request.  Note that ->bvec_count sum over all object requests may
	 * be greater than the number of bio_vecs in the provided bio (list)
	 * or bio_vec array because when mapped, those bio_vecs can straddle
	 * stripe unit boundaries.
2037
	 */
2038 2039
	fctx->iter = *fctx->pos;
	for (i = 0; i < num_img_extents; i++) {
2040
		ret = ceph_file_to_extents(&rbd_dev->layout,
2041 2042 2043 2044
					   img_extents[i].fe_off,
					   img_extents[i].fe_len,
					   &img_req->object_extents,
					   alloc_object_extent, img_req,
2045 2046 2047
					   fctx->count_fn, &fctx->iter);
		if (ret)
			return ret;
2048
	}
2049

2050 2051 2052 2053 2054 2055 2056
	for_each_obj_request(img_req, obj_req) {
		obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count,
					      sizeof(*obj_req->bvec_pos.bvecs),
					      GFP_NOIO);
		if (!obj_req->bvec_pos.bvecs)
			return -ENOMEM;
	}
2057

2058
	/*
2059 2060
	 * Fill in each object request's private bio_vec array, splitting and
	 * rearranging the provided bio_vecs in stripe unit chunks as needed.
2061
	 */
2062 2063 2064 2065 2066 2067 2068
	fctx->iter = *fctx->pos;
	for (i = 0; i < num_img_extents; i++) {
		ret = ceph_iterate_extents(&rbd_dev->layout,
					   img_extents[i].fe_off,
					   img_extents[i].fe_len,
					   &img_req->object_extents,
					   fctx->copy_fn, &fctx->iter);
2069 2070 2071
		if (ret)
			return ret;
	}
2072

2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093
	return __rbd_img_fill_request(img_req);
}

static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
			       u64 off, u64 len)
{
	struct ceph_file_extent ex = { off, len };
	union rbd_img_fill_iter dummy;
	struct rbd_img_fill_ctx fctx = {
		.pos_type = OBJ_REQUEST_NODATA,
		.pos = &dummy,
	};

	return rbd_img_fill_request(img_req, &ex, 1, &fctx);
}

static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bio_iter *it = arg;
2094

2095 2096 2097 2098
	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
	obj_req->bio_pos = *it;
	ceph_bio_iter_advance(it, bytes);
}
2099

2100 2101 2102 2103 2104
static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bio_iter *it = arg;
2105

2106 2107 2108 2109
	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
	ceph_bio_iter_advance_step(it, bytes, ({
		obj_req->bvec_count++;
	}));
2110

2111
}
2112

2113 2114 2115 2116 2117
static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bio_iter *it = arg;
2118

2119 2120 2121 2122 2123
	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
	ceph_bio_iter_advance_step(it, bytes, ({
		obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
		obj_req->bvec_pos.iter.bi_size += bv.bv_len;
	}));
2124 2125
}

2126 2127 2128 2129 2130 2131 2132 2133 2134
static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req,
				   struct ceph_file_extent *img_extents,
				   u32 num_img_extents,
				   struct ceph_bio_iter *bio_pos)
{
	struct rbd_img_fill_ctx fctx = {
		.pos_type = OBJ_REQUEST_BIO,
		.pos = (union rbd_img_fill_iter *)bio_pos,
		.set_pos_fn = set_bio_pos,
2135 2136
		.count_fn = count_bio_bvecs,
		.copy_fn = copy_bio_bvecs,
2137
	};
2138

2139 2140 2141
	return rbd_img_fill_request(img_req, img_extents, num_img_extents,
				    &fctx);
}
2142

2143 2144 2145 2146 2147
static int rbd_img_fill_from_bio(struct rbd_img_request *img_req,
				 u64 off, u64 len, struct bio *bio)
{
	struct ceph_file_extent ex = { off, len };
	struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter };
2148

2149 2150
	return __rbd_img_fill_from_bio(img_req, &ex, 1, &it);
}
A
Alex Elder 已提交
2151

2152 2153 2154 2155 2156
static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bvec_iter *it = arg;
2157

2158 2159 2160 2161
	obj_req->bvec_pos = *it;
	ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes);
	ceph_bvec_iter_advance(it, bytes);
}
2162

2163 2164 2165 2166 2167
static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bvec_iter *it = arg;
2168

2169 2170 2171 2172
	ceph_bvec_iter_advance_step(it, bytes, ({
		obj_req->bvec_count++;
	}));
}
2173

2174 2175 2176 2177 2178
static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
{
	struct rbd_obj_request *obj_req =
	    container_of(ex, struct rbd_obj_request, ex);
	struct ceph_bvec_iter *it = arg;
2179

2180 2181 2182 2183
	ceph_bvec_iter_advance_step(it, bytes, ({
		obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
		obj_req->bvec_pos.iter.bi_size += bv.bv_len;
	}));
2184 2185
}

2186 2187 2188 2189
static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
				     struct ceph_file_extent *img_extents,
				     u32 num_img_extents,
				     struct ceph_bvec_iter *bvec_pos)
2190
{
2191 2192 2193 2194
	struct rbd_img_fill_ctx fctx = {
		.pos_type = OBJ_REQUEST_BVECS,
		.pos = (union rbd_img_fill_iter *)bvec_pos,
		.set_pos_fn = set_bvec_pos,
2195 2196
		.count_fn = count_bvecs,
		.copy_fn = copy_bvecs,
2197
	};
2198

2199 2200 2201
	return rbd_img_fill_request(img_req, img_extents, num_img_extents,
				    &fctx);
}
2202

2203 2204 2205 2206 2207 2208 2209 2210 2211 2212
static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
				   struct ceph_file_extent *img_extents,
				   u32 num_img_extents,
				   struct bio_vec *bvecs)
{
	struct ceph_bvec_iter it = {
		.bvecs = bvecs,
		.iter = { .bi_size = ceph_file_extents_bytes(img_extents,
							     num_img_extents) },
	};
2213

2214 2215 2216
	return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents,
					 &it);
}
2217

2218
static void rbd_img_request_submit(struct rbd_img_request *img_request)
A
Alex Elder 已提交
2219 2220
{
	struct rbd_obj_request *obj_request;
2221

A
Alex Elder 已提交
2222
	dout("%s: img %p\n", __func__, img_request);
2223

2224
	rbd_img_request_get(img_request);
2225
	for_each_obj_request(img_request, obj_request)
I
Ilya Dryomov 已提交
2226
		rbd_obj_request_submit(obj_request);
2227

2228
	rbd_img_request_put(img_request);
2229 2230
}

I
Ilya Dryomov 已提交
2231
static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
2232
{
I
Ilya Dryomov 已提交
2233 2234
	struct rbd_img_request *img_req = obj_req->img_request;
	struct rbd_img_request *child_img_req;
2235 2236
	int ret;

2237 2238
	child_img_req = rbd_img_request_create(img_req->rbd_dev->parent,
					       OBJ_OP_READ, NULL);
I
Ilya Dryomov 已提交
2239
	if (!child_img_req)
2240 2241
		return -ENOMEM;

2242 2243
	__set_bit(IMG_REQ_CHILD, &child_img_req->flags);
	child_img_req->obj_request = obj_req;
2244

I
Ilya Dryomov 已提交
2245
	if (!rbd_img_is_write(img_req)) {
2246
		switch (img_req->data_type) {
I
Ilya Dryomov 已提交
2247
		case OBJ_REQUEST_BIO:
2248 2249 2250 2251
			ret = __rbd_img_fill_from_bio(child_img_req,
						      obj_req->img_extents,
						      obj_req->num_img_extents,
						      &obj_req->bio_pos);
I
Ilya Dryomov 已提交
2252 2253
			break;
		case OBJ_REQUEST_BVECS:
2254
		case OBJ_REQUEST_OWN_BVECS:
2255 2256 2257 2258
			ret = __rbd_img_fill_from_bvecs(child_img_req,
						      obj_req->img_extents,
						      obj_req->num_img_extents,
						      &obj_req->bvec_pos);
I
Ilya Dryomov 已提交
2259 2260 2261 2262 2263
			break;
		default:
			rbd_assert(0);
		}
	} else {
2264 2265 2266 2267
		ret = rbd_img_fill_from_bvecs(child_img_req,
					      obj_req->img_extents,
					      obj_req->num_img_extents,
					      obj_req->copyup_bvecs);
I
Ilya Dryomov 已提交
2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
	}
	if (ret) {
		rbd_img_request_put(child_img_req);
		return ret;
	}

	rbd_img_request_submit(child_img_req);
	return 0;
}

static bool rbd_obj_handle_read(struct rbd_obj_request *obj_req)
{
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
	int ret;

	if (obj_req->result == -ENOENT &&
I
Ilya Dryomov 已提交
2284 2285 2286
	    rbd_dev->parent_overlap && !obj_req->tried_parent) {
		/* reverse map this object extent onto the parent */
		ret = rbd_obj_calc_img_extents(obj_req, false);
I
Ilya Dryomov 已提交
2287 2288 2289 2290
		if (ret) {
			obj_req->result = ret;
			return true;
		}
I
Ilya Dryomov 已提交
2291 2292 2293 2294 2295 2296 2297 2298 2299 2300

		if (obj_req->num_img_extents) {
			obj_req->tried_parent = true;
			ret = rbd_obj_read_from_parent(obj_req);
			if (ret) {
				obj_req->result = ret;
				return true;
			}
			return false;
		}
2301 2302
	}

2303
	/*
I
Ilya Dryomov 已提交
2304 2305 2306 2307
	 * -ENOENT means a hole in the image -- zero-fill the entire
	 * length of the request.  A short read also implies zero-fill
	 * to the end of the request.  In both cases we update xferred
	 * count to indicate the whole request was satisfied.
2308
	 */
I
Ilya Dryomov 已提交
2309
	if (obj_req->result == -ENOENT ||
2310
	    (!obj_req->result && obj_req->xferred < obj_req->ex.oe_len)) {
I
Ilya Dryomov 已提交
2311 2312
		rbd_assert(!obj_req->xferred || !obj_req->result);
		rbd_obj_zero_range(obj_req, obj_req->xferred,
2313
				   obj_req->ex.oe_len - obj_req->xferred);
I
Ilya Dryomov 已提交
2314
		obj_req->result = 0;
2315
		obj_req->xferred = obj_req->ex.oe_len;
2316
	}
2317

I
Ilya Dryomov 已提交
2318 2319
	return true;
}
2320

I
Ilya Dryomov 已提交
2321 2322 2323 2324 2325 2326 2327 2328 2329
/*
 * copyup_bvecs pages are never highmem pages
 */
static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes)
{
	struct ceph_bvec_iter it = {
		.bvecs = bvecs,
		.iter = { .bi_size = bytes },
	};
2330

I
Ilya Dryomov 已提交
2331 2332 2333 2334 2335 2336
	ceph_bvec_iter_advance_step(&it, bytes, ({
		if (memchr_inv(page_address(bv.bv_page) + bv.bv_offset, 0,
			       bv.bv_len))
			return false;
	}));
	return true;
2337 2338
}

I
Ilya Dryomov 已提交
2339
static int rbd_obj_issue_copyup(struct rbd_obj_request *obj_req, u32 bytes)
2340
{
I
Ilya Dryomov 已提交
2341
	unsigned int num_osd_ops = obj_req->osd_req->r_num_ops;
2342
	int ret;
2343

I
Ilya Dryomov 已提交
2344 2345 2346
	dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
	rbd_assert(obj_req->osd_req->r_ops[0].op == CEPH_OSD_OP_STAT);
	rbd_osd_req_destroy(obj_req->osd_req);
2347

2348
	/*
I
Ilya Dryomov 已提交
2349 2350 2351
	 * Create a copyup request with the same number of OSD ops as
	 * the original request.  The original request was stat + op(s),
	 * the new copyup request will be copyup + the same op(s).
2352
	 */
2353
	obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops);
I
Ilya Dryomov 已提交
2354 2355
	if (!obj_req->osd_req)
		return -ENOMEM;
2356

2357 2358 2359 2360 2361
	ret = osd_req_op_cls_init(obj_req->osd_req, 0, CEPH_OSD_OP_CALL, "rbd",
				  "copyup");
	if (ret)
		return ret;

2362
	/*
I
Ilya Dryomov 已提交
2363 2364 2365
	 * Only send non-zero copyup data to save some I/O and network
	 * bandwidth -- zero copyup data is equivalent to the object not
	 * existing.
2366
	 */
I
Ilya Dryomov 已提交
2367 2368 2369 2370 2371
	if (is_zero_bvecs(obj_req->copyup_bvecs, bytes)) {
		dout("%s obj_req %p detected zeroes\n", __func__, obj_req);
		bytes = 0;
	}
	osd_req_op_cls_request_data_bvecs(obj_req->osd_req, 0,
2372 2373 2374
					  obj_req->copyup_bvecs,
					  obj_req->copyup_bvec_count,
					  bytes);
I
Ilya Dryomov 已提交
2375

I
Ilya Dryomov 已提交
2376
	switch (obj_req->img_request->op_type) {
I
Ilya Dryomov 已提交
2377 2378 2379 2380 2381 2382 2383 2384 2385 2386
	case OBJ_OP_WRITE:
		__rbd_obj_setup_write(obj_req, 1);
		break;
	case OBJ_OP_DISCARD:
		rbd_assert(!rbd_obj_is_entire(obj_req));
		__rbd_obj_setup_discard(obj_req, 1);
		break;
	default:
		rbd_assert(0);
	}
2387

I
Ilya Dryomov 已提交
2388 2389
	rbd_obj_request_submit(obj_req);
	return 0;
2390 2391
}

2392
static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap)
2393
{
2394
	u32 i;
2395

2396 2397 2398 2399 2400 2401 2402
	rbd_assert(!obj_req->copyup_bvecs);
	obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap);
	obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count,
					sizeof(*obj_req->copyup_bvecs),
					GFP_NOIO);
	if (!obj_req->copyup_bvecs)
		return -ENOMEM;
2403

2404 2405 2406 2407 2408 2409
	for (i = 0; i < obj_req->copyup_bvec_count; i++) {
		unsigned int len = min(obj_overlap, (u64)PAGE_SIZE);

		obj_req->copyup_bvecs[i].bv_page = alloc_page(GFP_NOIO);
		if (!obj_req->copyup_bvecs[i].bv_page)
			return -ENOMEM;
2410

2411 2412 2413 2414
		obj_req->copyup_bvecs[i].bv_offset = 0;
		obj_req->copyup_bvecs[i].bv_len = len;
		obj_overlap -= len;
	}
2415

2416 2417
	rbd_assert(!obj_overlap);
	return 0;
2418 2419
}

I
Ilya Dryomov 已提交
2420
static int rbd_obj_handle_write_guard(struct rbd_obj_request *obj_req)
A
Alex Elder 已提交
2421
{
I
Ilya Dryomov 已提交
2422 2423
	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
	int ret;
A
Alex Elder 已提交
2424

I
Ilya Dryomov 已提交
2425 2426 2427 2428
	rbd_assert(obj_req->num_img_extents);
	prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
		      rbd_dev->parent_overlap);
	if (!obj_req->num_img_extents) {
I
Ilya Dryomov 已提交
2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439
		/*
		 * The overlap has become 0 (most likely because the
		 * image has been flattened).  Use rbd_obj_issue_copyup()
		 * to re-submit the original write request -- the copyup
		 * operation itself will be a no-op, since someone must
		 * have populated the child object while we weren't
		 * looking.  Move to WRITE_FLAT state as we'll be done
		 * with the operation once the null copyup completes.
		 */
		obj_req->write_state = RBD_OBJ_WRITE_FLAT;
		return rbd_obj_issue_copyup(obj_req, 0);
A
Alex Elder 已提交
2440 2441
	}

I
Ilya Dryomov 已提交
2442
	ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req));
I
Ilya Dryomov 已提交
2443 2444 2445 2446
	if (ret)
		return ret;

	obj_req->write_state = RBD_OBJ_WRITE_COPYUP;
I
Ilya Dryomov 已提交
2447
	return rbd_obj_read_from_parent(obj_req);
A
Alex Elder 已提交
2448
}
A
Alex Elder 已提交
2449

I
Ilya Dryomov 已提交
2450
static bool rbd_obj_handle_write(struct rbd_obj_request *obj_req)
A
Alex Elder 已提交
2451
{
I
Ilya Dryomov 已提交
2452
	int ret;
A
Alex Elder 已提交
2453

I
Ilya Dryomov 已提交
2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477
again:
	switch (obj_req->write_state) {
	case RBD_OBJ_WRITE_GUARD:
		rbd_assert(!obj_req->xferred);
		if (obj_req->result == -ENOENT) {
			/*
			 * The target object doesn't exist.  Read the data for
			 * the entire target object up to the overlap point (if
			 * any) from the parent, so we can use it for a copyup.
			 */
			ret = rbd_obj_handle_write_guard(obj_req);
			if (ret) {
				obj_req->result = ret;
				return true;
			}
			return false;
		}
		/* fall through */
	case RBD_OBJ_WRITE_FLAT:
		if (!obj_req->result)
			/*
			 * There is no such thing as a successful short
			 * write -- indicate the whole request was satisfied.
			 */
2478
			obj_req->xferred = obj_req->ex.oe_len;
I
Ilya Dryomov 已提交
2479 2480 2481 2482 2483
		return true;
	case RBD_OBJ_WRITE_COPYUP:
		obj_req->write_state = RBD_OBJ_WRITE_GUARD;
		if (obj_req->result)
			goto again;
A
Alex Elder 已提交
2484

I
Ilya Dryomov 已提交
2485 2486 2487 2488 2489 2490 2491 2492
		rbd_assert(obj_req->xferred);
		ret = rbd_obj_issue_copyup(obj_req, obj_req->xferred);
		if (ret) {
			obj_req->result = ret;
			return true;
		}
		return false;
	default:
A
Arnd Bergmann 已提交
2493
		BUG();
I
Ilya Dryomov 已提交
2494 2495
	}
}
2496

I
Ilya Dryomov 已提交
2497 2498 2499 2500 2501
/*
 * Returns true if @obj_req is completed, or false otherwise.
 */
static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req)
{
I
Ilya Dryomov 已提交
2502
	switch (obj_req->img_request->op_type) {
I
Ilya Dryomov 已提交
2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514
	case OBJ_OP_READ:
		return rbd_obj_handle_read(obj_req);
	case OBJ_OP_WRITE:
		return rbd_obj_handle_write(obj_req);
	case OBJ_OP_DISCARD:
		if (rbd_obj_handle_write(obj_req)) {
			/*
			 * Hide -ENOENT from delete/truncate/zero -- discarding
			 * a non-existent object is not a problem.
			 */
			if (obj_req->result == -ENOENT) {
				obj_req->result = 0;
2515
				obj_req->xferred = obj_req->ex.oe_len;
I
Ilya Dryomov 已提交
2516 2517 2518 2519 2520
			}
			return true;
		}
		return false;
	default:
A
Arnd Bergmann 已提交
2521
		BUG();
I
Ilya Dryomov 已提交
2522 2523
	}
}
2524

I
Ilya Dryomov 已提交
2525 2526 2527 2528 2529
static void rbd_obj_end_request(struct rbd_obj_request *obj_req)
{
	struct rbd_img_request *img_req = obj_req->img_request;

	rbd_assert((!obj_req->result &&
2530
		    obj_req->xferred == obj_req->ex.oe_len) ||
I
Ilya Dryomov 已提交
2531 2532 2533
		   (obj_req->result < 0 && !obj_req->xferred));
	if (!obj_req->result) {
		img_req->xferred += obj_req->xferred;
2534
		return;
2535
	}
A
Alex Elder 已提交
2536

I
Ilya Dryomov 已提交
2537 2538
	rbd_warn(img_req->rbd_dev,
		 "%s at objno %llu %llu~%llu result %d xferred %llu",
2539 2540
		 obj_op_name(img_req->op_type), obj_req->ex.oe_objno,
		 obj_req->ex.oe_off, obj_req->ex.oe_len, obj_req->result,
I
Ilya Dryomov 已提交
2541 2542 2543 2544 2545 2546
		 obj_req->xferred);
	if (!img_req->result) {
		img_req->result = obj_req->result;
		img_req->xferred = 0;
	}
}
A
Alex Elder 已提交
2547

I
Ilya Dryomov 已提交
2548 2549 2550
static void rbd_img_end_child_request(struct rbd_img_request *img_req)
{
	struct rbd_obj_request *obj_req = img_req->obj_request;
A
Alex Elder 已提交
2551

I
Ilya Dryomov 已提交
2552
	rbd_assert(test_bit(IMG_REQ_CHILD, &img_req->flags));
I
Ilya Dryomov 已提交
2553 2554 2555
	rbd_assert((!img_req->result &&
		    img_req->xferred == rbd_obj_img_extents_bytes(obj_req)) ||
		   (img_req->result < 0 && !img_req->xferred));
A
Alex Elder 已提交
2556

I
Ilya Dryomov 已提交
2557 2558 2559
	obj_req->result = img_req->result;
	obj_req->xferred = img_req->xferred;
	rbd_img_request_put(img_req);
A
Alex Elder 已提交
2560 2561
}

I
Ilya Dryomov 已提交
2562
static void rbd_img_end_request(struct rbd_img_request *img_req)
A
Alex Elder 已提交
2563
{
I
Ilya Dryomov 已提交
2564 2565 2566 2567
	rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags));
	rbd_assert((!img_req->result &&
		    img_req->xferred == blk_rq_bytes(img_req->rq)) ||
		   (img_req->result < 0 && !img_req->xferred));
A
Alex Elder 已提交
2568

I
Ilya Dryomov 已提交
2569 2570 2571
	blk_mq_end_request(img_req->rq,
			   errno_to_blk_status(img_req->result));
	rbd_img_request_put(img_req);
I
Ilya Dryomov 已提交
2572
}
A
Alex Elder 已提交
2573

I
Ilya Dryomov 已提交
2574 2575
static void rbd_obj_handle_request(struct rbd_obj_request *obj_req)
{
I
Ilya Dryomov 已提交
2576
	struct rbd_img_request *img_req;
A
Alex Elder 已提交
2577

I
Ilya Dryomov 已提交
2578
again:
I
Ilya Dryomov 已提交
2579 2580
	if (!__rbd_obj_handle_request(obj_req))
		return;
A
Alex Elder 已提交
2581

I
Ilya Dryomov 已提交
2582 2583 2584 2585 2586 2587 2588 2589
	img_req = obj_req->img_request;
	spin_lock(&img_req->completion_lock);
	rbd_obj_end_request(obj_req);
	rbd_assert(img_req->pending_count);
	if (--img_req->pending_count) {
		spin_unlock(&img_req->completion_lock);
		return;
	}
A
Alex Elder 已提交
2590

I
Ilya Dryomov 已提交
2591 2592 2593 2594 2595 2596 2597
	spin_unlock(&img_req->completion_lock);
	if (test_bit(IMG_REQ_CHILD, &img_req->flags)) {
		obj_req = img_req->obj_request;
		rbd_img_end_child_request(img_req);
		goto again;
	}
	rbd_img_end_request(img_req);
A
Alex Elder 已提交
2598
}
A
Alex Elder 已提交
2599

2600
static const struct rbd_client_id rbd_empty_cid;
A
Alex Elder 已提交
2601

2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637
static bool rbd_cid_equal(const struct rbd_client_id *lhs,
			  const struct rbd_client_id *rhs)
{
	return lhs->gid == rhs->gid && lhs->handle == rhs->handle;
}

static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev)
{
	struct rbd_client_id cid;

	mutex_lock(&rbd_dev->watch_mutex);
	cid.gid = ceph_client_gid(rbd_dev->rbd_client->client);
	cid.handle = rbd_dev->watch_cookie;
	mutex_unlock(&rbd_dev->watch_mutex);
	return cid;
}

/*
 * lock_rwsem must be held for write
 */
static void rbd_set_owner_cid(struct rbd_device *rbd_dev,
			      const struct rbd_client_id *cid)
{
	dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev,
	     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle,
	     cid->gid, cid->handle);
	rbd_dev->owner_cid = *cid; /* struct */
}

static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
{
	mutex_lock(&rbd_dev->watch_mutex);
	sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie);
	mutex_unlock(&rbd_dev->watch_mutex);
}

2638 2639 2640 2641 2642 2643 2644 2645 2646
static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
{
	struct rbd_client_id cid = rbd_get_cid(rbd_dev);

	strcpy(rbd_dev->lock_cookie, cookie);
	rbd_set_owner_cid(rbd_dev, &cid);
	queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
}

2647 2648 2649 2650
/*
 * lock_rwsem must be held for write
 */
static int rbd_lock(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
2651
{
2652
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2653
	char cookie[32];
2654
	int ret;
A
Alex Elder 已提交
2655

I
Ilya Dryomov 已提交
2656 2657
	WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
		rbd_dev->lock_cookie[0] != '\0');
2658

2659 2660 2661 2662
	format_lock_cookie(rbd_dev, cookie);
	ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
			    RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie,
			    RBD_LOCK_TAG, "", 0);
2663
	if (ret)
2664
		return ret;
A
Alex Elder 已提交
2665

2666
	rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
2667
	__rbd_lock(rbd_dev, cookie);
2668
	return 0;
A
Alex Elder 已提交
2669 2670
}

2671 2672 2673
/*
 * lock_rwsem must be held for write
 */
I
Ilya Dryomov 已提交
2674
static void rbd_unlock(struct rbd_device *rbd_dev)
2675
{
2676
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2677 2678
	int ret;

I
Ilya Dryomov 已提交
2679 2680
	WARN_ON(!__rbd_is_lock_owner(rbd_dev) ||
		rbd_dev->lock_cookie[0] == '\0');
2681

2682
	ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
I
Ilya Dryomov 已提交
2683
			      RBD_LOCK_NAME, rbd_dev->lock_cookie);
I
Ilya Dryomov 已提交
2684 2685
	if (ret && ret != -ENOENT)
		rbd_warn(rbd_dev, "failed to unlock: %d", ret);
2686

I
Ilya Dryomov 已提交
2687 2688
	/* treat errors as the image is unlocked */
	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
I
Ilya Dryomov 已提交
2689
	rbd_dev->lock_cookie[0] = '\0';
2690 2691
	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
	queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work);
2692 2693
}

2694 2695 2696 2697
static int __rbd_notify_op_lock(struct rbd_device *rbd_dev,
				enum rbd_notify_op notify_op,
				struct page ***preply_pages,
				size_t *preply_len)
2698 2699
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2700
	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
K
Kyle Spiers 已提交
2701 2702
	char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN];
	int buf_size = sizeof(buf);
2703
	void *p = buf;
2704

2705
	dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op);
2706

2707 2708 2709 2710 2711
	/* encode *LockPayload NotifyMessage (op + ClientId) */
	ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_32(&p, notify_op);
	ceph_encode_64(&p, cid.gid);
	ceph_encode_64(&p, cid.handle);
2712

2713 2714 2715
	return ceph_osdc_notify(osdc, &rbd_dev->header_oid,
				&rbd_dev->header_oloc, buf, buf_size,
				RBD_NOTIFY_TIMEOUT, preply_pages, preply_len);
2716 2717
}

2718 2719
static void rbd_notify_op_lock(struct rbd_device *rbd_dev,
			       enum rbd_notify_op notify_op)
2720
{
2721 2722
	struct page **reply_pages;
	size_t reply_len;
2723

2724 2725 2726
	__rbd_notify_op_lock(rbd_dev, notify_op, &reply_pages, &reply_len);
	ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
}
2727

2728 2729 2730 2731
static void rbd_notify_acquired_lock(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  acquired_lock_work);
2732

2733
	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK);
2734 2735
}

2736
static void rbd_notify_released_lock(struct work_struct *work)
2737
{
2738 2739
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  released_lock_work);
I
Ilya Dryomov 已提交
2740

2741
	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK);
2742 2743
}

2744
static int rbd_request_lock(struct rbd_device *rbd_dev)
2745
{
2746 2747 2748
	struct page **reply_pages;
	size_t reply_len;
	bool lock_owner_responded = false;
2749 2750
	int ret;

2751
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
2752

2753 2754 2755 2756
	ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK,
				   &reply_pages, &reply_len);
	if (ret && ret != -ETIMEDOUT) {
		rbd_warn(rbd_dev, "failed to request lock: %d", ret);
2757
		goto out;
2758
	}
2759

2760 2761 2762 2763
	if (reply_len > 0 && reply_len <= PAGE_SIZE) {
		void *p = page_address(reply_pages[0]);
		void *const end = p + reply_len;
		u32 n;
2764

2765 2766 2767 2768
		ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */
		while (n--) {
			u8 struct_v;
			u32 len;
2769

2770 2771
			ceph_decode_need(&p, end, 8 + 8, e_inval);
			p += 8 + 8; /* skip gid and cookie */
2772

2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004
			ceph_decode_32_safe(&p, end, len, e_inval);
			if (!len)
				continue;

			if (lock_owner_responded) {
				rbd_warn(rbd_dev,
					 "duplicate lock owners detected");
				ret = -EIO;
				goto out;
			}

			lock_owner_responded = true;
			ret = ceph_start_decoding(&p, end, 1, "ResponseMessage",
						  &struct_v, &len);
			if (ret) {
				rbd_warn(rbd_dev,
					 "failed to decode ResponseMessage: %d",
					 ret);
				goto e_inval;
			}

			ret = ceph_decode_32(&p);
		}
	}

	if (!lock_owner_responded) {
		rbd_warn(rbd_dev, "no lock owners detected");
		ret = -ETIMEDOUT;
	}

out:
	ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
	return ret;

e_inval:
	ret = -EINVAL;
	goto out;
}

static void wake_requests(struct rbd_device *rbd_dev, bool wake_all)
{
	dout("%s rbd_dev %p wake_all %d\n", __func__, rbd_dev, wake_all);

	cancel_delayed_work(&rbd_dev->lock_dwork);
	if (wake_all)
		wake_up_all(&rbd_dev->lock_waitq);
	else
		wake_up(&rbd_dev->lock_waitq);
}

static int get_lock_owner_info(struct rbd_device *rbd_dev,
			       struct ceph_locker **lockers, u32 *num_lockers)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	u8 lock_type;
	char *lock_tag;
	int ret;

	dout("%s rbd_dev %p\n", __func__, rbd_dev);

	ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
				 &rbd_dev->header_oloc, RBD_LOCK_NAME,
				 &lock_type, &lock_tag, lockers, num_lockers);
	if (ret)
		return ret;

	if (*num_lockers == 0) {
		dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
		goto out;
	}

	if (strcmp(lock_tag, RBD_LOCK_TAG)) {
		rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
			 lock_tag);
		ret = -EBUSY;
		goto out;
	}

	if (lock_type == CEPH_CLS_LOCK_SHARED) {
		rbd_warn(rbd_dev, "shared lock type detected");
		ret = -EBUSY;
		goto out;
	}

	if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX,
		    strlen(RBD_LOCK_COOKIE_PREFIX))) {
		rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
			 (*lockers)[0].id.cookie);
		ret = -EBUSY;
		goto out;
	}

out:
	kfree(lock_tag);
	return ret;
}

static int find_watcher(struct rbd_device *rbd_dev,
			const struct ceph_locker *locker)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_watch_item *watchers;
	u32 num_watchers;
	u64 cookie;
	int i;
	int ret;

	ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid,
				      &rbd_dev->header_oloc, &watchers,
				      &num_watchers);
	if (ret)
		return ret;

	sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie);
	for (i = 0; i < num_watchers; i++) {
		if (!memcmp(&watchers[i].addr, &locker->info.addr,
			    sizeof(locker->info.addr)) &&
		    watchers[i].cookie == cookie) {
			struct rbd_client_id cid = {
				.gid = le64_to_cpu(watchers[i].name.num),
				.handle = cookie,
			};

			dout("%s rbd_dev %p found cid %llu-%llu\n", __func__,
			     rbd_dev, cid.gid, cid.handle);
			rbd_set_owner_cid(rbd_dev, &cid);
			ret = 1;
			goto out;
		}
	}

	dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev);
	ret = 0;
out:
	kfree(watchers);
	return ret;
}

/*
 * lock_rwsem must be held for write
 */
static int rbd_try_lock(struct rbd_device *rbd_dev)
{
	struct ceph_client *client = rbd_dev->rbd_client->client;
	struct ceph_locker *lockers;
	u32 num_lockers;
	int ret;

	for (;;) {
		ret = rbd_lock(rbd_dev);
		if (ret != -EBUSY)
			return ret;

		/* determine if the current lock holder is still alive */
		ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers);
		if (ret)
			return ret;

		if (num_lockers == 0)
			goto again;

		ret = find_watcher(rbd_dev, lockers);
		if (ret) {
			if (ret > 0)
				ret = 0; /* have to request lock */
			goto out;
		}

		rbd_warn(rbd_dev, "%s%llu seems dead, breaking lock",
			 ENTITY_NAME(lockers[0].id.name));

		ret = ceph_monc_blacklist_add(&client->monc,
					      &lockers[0].info.addr);
		if (ret) {
			rbd_warn(rbd_dev, "blacklist of %s%llu failed: %d",
				 ENTITY_NAME(lockers[0].id.name), ret);
			goto out;
		}

		ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
					  &rbd_dev->header_oloc, RBD_LOCK_NAME,
					  lockers[0].id.cookie,
					  &lockers[0].id.name);
		if (ret && ret != -ENOENT)
			goto out;

again:
		ceph_free_lockers(lockers, num_lockers);
	}

out:
	ceph_free_lockers(lockers, num_lockers);
	return ret;
}

/*
 * ret is set only if lock_state is RBD_LOCK_STATE_UNLOCKED
 */
static enum rbd_lock_state rbd_try_acquire_lock(struct rbd_device *rbd_dev,
						int *pret)
{
	enum rbd_lock_state lock_state;

	down_read(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (__rbd_is_lock_owner(rbd_dev)) {
		lock_state = rbd_dev->lock_state;
		up_read(&rbd_dev->lock_rwsem);
		return lock_state;
	}

	up_read(&rbd_dev->lock_rwsem);
	down_write(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (!__rbd_is_lock_owner(rbd_dev)) {
		*pret = rbd_try_lock(rbd_dev);
		if (*pret)
			rbd_warn(rbd_dev, "failed to acquire lock: %d", *pret);
	}

	lock_state = rbd_dev->lock_state;
	up_write(&rbd_dev->lock_rwsem);
	return lock_state;
}

static void rbd_acquire_lock(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
					    struct rbd_device, lock_dwork);
	enum rbd_lock_state lock_state;
3005
	int ret = 0;
3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020

	dout("%s rbd_dev %p\n", __func__, rbd_dev);
again:
	lock_state = rbd_try_acquire_lock(rbd_dev, &ret);
	if (lock_state != RBD_LOCK_STATE_UNLOCKED || ret == -EBLACKLISTED) {
		if (lock_state == RBD_LOCK_STATE_LOCKED)
			wake_requests(rbd_dev, true);
		dout("%s rbd_dev %p lock_state %d ret %d - done\n", __func__,
		     rbd_dev, lock_state, ret);
		return;
	}

	ret = rbd_request_lock(rbd_dev);
	if (ret == -ETIMEDOUT) {
		goto again; /* treat this as a dead client */
I
Ilya Dryomov 已提交
3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032
	} else if (ret == -EROFS) {
		rbd_warn(rbd_dev, "peer will not release lock");
		/*
		 * If this is rbd_add_acquire_lock(), we want to fail
		 * immediately -- reuse BLACKLISTED flag.  Otherwise we
		 * want to block.
		 */
		if (!(rbd_dev->disk->flags & GENHD_FL_UP)) {
			set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags);
			/* wake "rbd map --exclusive" process */
			wake_requests(rbd_dev, false);
		}
3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060
	} else if (ret < 0) {
		rbd_warn(rbd_dev, "error requesting lock: %d", ret);
		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
				 RBD_RETRY_DELAY);
	} else {
		/*
		 * lock owner acked, but resend if we don't see them
		 * release the lock
		 */
		dout("%s rbd_dev %p requeueing lock_dwork\n", __func__,
		     rbd_dev);
		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
		    msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
	}
}

/*
 * lock_rwsem must be held for write
 */
static bool rbd_release_lock(struct rbd_device *rbd_dev)
{
	dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED)
		return false;

	rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING;
	downgrade_write(&rbd_dev->lock_rwsem);
3061
	/*
3062
	 * Ensure that all in-flight IO is flushed.
3063
	 *
3064 3065
	 * FIXME: ceph_osdc_sync() flushes the entire OSD client, which
	 * may be shared with other devices.
3066
	 */
3067 3068 3069 3070 3071 3072 3073 3074 3075
	ceph_osdc_sync(&rbd_dev->rbd_client->client->osdc);
	up_read(&rbd_dev->lock_rwsem);

	down_write(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING)
		return false;

I
Ilya Dryomov 已提交
3076 3077 3078 3079 3080 3081 3082 3083 3084
	rbd_unlock(rbd_dev);
	/*
	 * Give others a chance to grab the lock - we would re-acquire
	 * almost immediately if we got new IO during ceph_osdc_sync()
	 * otherwise.  We need to ack our own notifications, so this
	 * lock_dwork will be requeued from rbd_wait_state_locked()
	 * after wake_requests() in rbd_handle_released_lock().
	 */
	cancel_delayed_work(&rbd_dev->lock_dwork);
3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164
	return true;
}

static void rbd_release_lock_work(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  unlock_work);

	down_write(&rbd_dev->lock_rwsem);
	rbd_release_lock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);
}

static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v,
				     void **p)
{
	struct rbd_client_id cid = { 0 };

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
		down_write(&rbd_dev->lock_rwsem);
		if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
			/*
			 * we already know that the remote client is
			 * the owner
			 */
			up_write(&rbd_dev->lock_rwsem);
			return;
		}

		rbd_set_owner_cid(rbd_dev, &cid);
		downgrade_write(&rbd_dev->lock_rwsem);
	} else {
		down_read(&rbd_dev->lock_rwsem);
	}

	if (!__rbd_is_lock_owner(rbd_dev))
		wake_requests(rbd_dev, false);
	up_read(&rbd_dev->lock_rwsem);
}

static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v,
				     void **p)
{
	struct rbd_client_id cid = { 0 };

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
		down_write(&rbd_dev->lock_rwsem);
		if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
			dout("%s rbd_dev %p unexpected owner, cid %llu-%llu != owner_cid %llu-%llu\n",
			     __func__, rbd_dev, cid.gid, cid.handle,
			     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle);
			up_write(&rbd_dev->lock_rwsem);
			return;
		}

		rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
		downgrade_write(&rbd_dev->lock_rwsem);
	} else {
		down_read(&rbd_dev->lock_rwsem);
	}

	if (!__rbd_is_lock_owner(rbd_dev))
		wake_requests(rbd_dev, false);
	up_read(&rbd_dev->lock_rwsem);
}

3165 3166 3167 3168 3169 3170
/*
 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no
 * ResponseMessage is needed.
 */
static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v,
				   void **p)
3171 3172 3173
{
	struct rbd_client_id my_cid = rbd_get_cid(rbd_dev);
	struct rbd_client_id cid = { 0 };
3174
	int result = 1;
3175 3176 3177 3178 3179 3180 3181 3182 3183

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (rbd_cid_equal(&cid, &my_cid))
3184
		return result;
3185 3186

	down_read(&rbd_dev->lock_rwsem);
3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198
	if (__rbd_is_lock_owner(rbd_dev)) {
		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED &&
		    rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid))
			goto out_unlock;

		/*
		 * encode ResponseMessage(0) so the peer can detect
		 * a missing owner
		 */
		result = 0;

		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) {
I
Ilya Dryomov 已提交
3199 3200 3201 3202 3203 3204 3205 3206 3207
			if (!rbd_dev->opts->exclusive) {
				dout("%s rbd_dev %p queueing unlock_work\n",
				     __func__, rbd_dev);
				queue_work(rbd_dev->task_wq,
					   &rbd_dev->unlock_work);
			} else {
				/* refuse to release the lock */
				result = -EROFS;
			}
3208 3209
		}
	}
3210 3211

out_unlock:
3212
	up_read(&rbd_dev->lock_rwsem);
3213
	return result;
3214 3215 3216 3217 3218 3219
}

static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev,
				     u64 notify_id, u64 cookie, s32 *result)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
K
Kyle Spiers 已提交
3220 3221
	char buf[4 + CEPH_ENCODING_START_BLK_LEN];
	int buf_size = sizeof(buf);
3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233
	int ret;

	if (result) {
		void *p = buf;

		/* encode ResponseMessage */
		ceph_start_encoding(&p, 1, 1,
				    buf_size - CEPH_ENCODING_START_BLK_LEN);
		ceph_encode_32(&p, *result);
	} else {
		buf_size = 0;
	}
A
Alex Elder 已提交
3234

3235 3236
	ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid,
				   &rbd_dev->header_oloc, notify_id, cookie,
3237
				   buf, buf_size);
3238
	if (ret)
3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261
		rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret);
}

static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id,
				   u64 cookie)
{
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL);
}

static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev,
					  u64 notify_id, u64 cookie, s32 result)
{
	dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result);
}

static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie,
			 u64 notifier_id, void *data, size_t data_len)
{
	struct rbd_device *rbd_dev = arg;
	void *p = data;
	void *const end = p + data_len;
3262
	u8 struct_v = 0;
3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295
	u32 len;
	u32 notify_op;
	int ret;

	dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n",
	     __func__, rbd_dev, cookie, notify_id, data_len);
	if (data_len) {
		ret = ceph_start_decoding(&p, end, 1, "NotifyMessage",
					  &struct_v, &len);
		if (ret) {
			rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d",
				 ret);
			return;
		}

		notify_op = ceph_decode_32(&p);
	} else {
		/* legacy notification for header updates */
		notify_op = RBD_NOTIFY_OP_HEADER_UPDATE;
		len = 0;
	}

	dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op);
	switch (notify_op) {
	case RBD_NOTIFY_OP_ACQUIRED_LOCK:
		rbd_handle_acquired_lock(rbd_dev, struct_v, &p);
		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_RELEASED_LOCK:
		rbd_handle_released_lock(rbd_dev, struct_v, &p);
		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_REQUEST_LOCK:
3296 3297
		ret = rbd_handle_request_lock(rbd_dev, struct_v, &p);
		if (ret <= 0)
3298
			rbd_acknowledge_notify_result(rbd_dev, notify_id,
3299
						      cookie, ret);
3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317
		else
			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_HEADER_UPDATE:
		ret = rbd_dev_refresh(rbd_dev);
		if (ret)
			rbd_warn(rbd_dev, "refresh failed: %d", ret);

		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	default:
		if (rbd_is_lock_owner(rbd_dev))
			rbd_acknowledge_notify_result(rbd_dev, notify_id,
						      cookie, -EOPNOTSUPP);
		else
			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	}
A
Alex Elder 已提交
3318 3319
}

3320 3321
static void __rbd_unregister_watch(struct rbd_device *rbd_dev);

3322
static void rbd_watch_errcb(void *arg, u64 cookie, int err)
3323
{
3324
	struct rbd_device *rbd_dev = arg;
3325

3326
	rbd_warn(rbd_dev, "encountered watch error: %d", err);
3327

3328 3329 3330 3331
	down_write(&rbd_dev->lock_rwsem);
	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
	up_write(&rbd_dev->lock_rwsem);

3332 3333 3334 3335
	mutex_lock(&rbd_dev->watch_mutex);
	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) {
		__rbd_unregister_watch(rbd_dev);
		rbd_dev->watch_state = RBD_WATCH_STATE_ERROR;
3336

3337
		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0);
3338
	}
3339
	mutex_unlock(&rbd_dev->watch_mutex);
3340 3341
}

3342
/*
3343
 * watch_mutex must be locked
3344
 */
3345
static int __rbd_register_watch(struct rbd_device *rbd_dev)
3346 3347
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3348
	struct ceph_osd_linger_request *handle;
3349

3350
	rbd_assert(!rbd_dev->watch_handle);
3351
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3352

3353 3354 3355 3356 3357
	handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid,
				 &rbd_dev->header_oloc, rbd_watch_cb,
				 rbd_watch_errcb, rbd_dev);
	if (IS_ERR(handle))
		return PTR_ERR(handle);
3358

3359
	rbd_dev->watch_handle = handle;
3360 3361 3362
	return 0;
}

3363 3364 3365 3366
/*
 * watch_mutex must be locked
 */
static void __rbd_unregister_watch(struct rbd_device *rbd_dev)
3367
{
3368 3369
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	int ret;
3370

3371 3372
	rbd_assert(rbd_dev->watch_handle);
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3373

3374 3375 3376
	ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle);
	if (ret)
		rbd_warn(rbd_dev, "failed to unwatch: %d", ret);
3377

3378
	rbd_dev->watch_handle = NULL;
3379 3380
}

3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399
static int rbd_register_watch(struct rbd_device *rbd_dev)
{
	int ret;

	mutex_lock(&rbd_dev->watch_mutex);
	rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED);
	ret = __rbd_register_watch(rbd_dev);
	if (ret)
		goto out;

	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;

out:
	mutex_unlock(&rbd_dev->watch_mutex);
	return ret;
}

static void cancel_tasks_sync(struct rbd_device *rbd_dev)
3400
{
3401 3402
	dout("%s rbd_dev %p\n", __func__, rbd_dev);

3403 3404 3405 3406
	cancel_work_sync(&rbd_dev->acquired_lock_work);
	cancel_work_sync(&rbd_dev->released_lock_work);
	cancel_delayed_work_sync(&rbd_dev->lock_dwork);
	cancel_work_sync(&rbd_dev->unlock_work);
3407 3408 3409 3410
}

static void rbd_unregister_watch(struct rbd_device *rbd_dev)
{
3411
	WARN_ON(waitqueue_active(&rbd_dev->lock_waitq));
3412 3413 3414 3415 3416 3417 3418
	cancel_tasks_sync(rbd_dev);

	mutex_lock(&rbd_dev->watch_mutex);
	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED)
		__rbd_unregister_watch(rbd_dev);
	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
	mutex_unlock(&rbd_dev->watch_mutex);
I
Ilya Dryomov 已提交
3419

3420
	cancel_delayed_work_sync(&rbd_dev->watch_dwork);
I
Ilya Dryomov 已提交
3421
	ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
3422 3423
}

3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452
/*
 * lock_rwsem must be held for write
 */
static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	char cookie[32];
	int ret;

	WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED);

	format_lock_cookie(rbd_dev, cookie);
	ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, RBD_LOCK_NAME,
				  CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie,
				  RBD_LOCK_TAG, cookie);
	if (ret) {
		if (ret != -EOPNOTSUPP)
			rbd_warn(rbd_dev, "failed to update lock cookie: %d",
				 ret);

		/*
		 * Lock cookie cannot be updated on older OSDs, so do
		 * a manual release and queue an acquire.
		 */
		if (rbd_release_lock(rbd_dev))
			queue_delayed_work(rbd_dev->task_wq,
					   &rbd_dev->lock_dwork, 0);
	} else {
3453
		__rbd_lock(rbd_dev, cookie);
3454 3455 3456
	}
}

3457 3458 3459 3460 3461 3462 3463 3464 3465
static void rbd_reregister_watch(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
					    struct rbd_device, watch_dwork);
	int ret;

	dout("%s rbd_dev %p\n", __func__, rbd_dev);

	mutex_lock(&rbd_dev->watch_mutex);
3466 3467
	if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) {
		mutex_unlock(&rbd_dev->watch_mutex);
3468
		return;
3469
	}
3470 3471 3472 3473

	ret = __rbd_register_watch(rbd_dev);
	if (ret) {
		rbd_warn(rbd_dev, "failed to reregister watch: %d", ret);
3474
		if (ret == -EBLACKLISTED || ret == -ENOENT) {
3475
			set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags);
3476
			wake_requests(rbd_dev, true);
3477
		} else {
3478 3479 3480
			queue_delayed_work(rbd_dev->task_wq,
					   &rbd_dev->watch_dwork,
					   RBD_RETRY_DELAY);
3481 3482
		}
		mutex_unlock(&rbd_dev->watch_mutex);
3483
		return;
3484 3485 3486 3487 3488 3489
	}

	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
	mutex_unlock(&rbd_dev->watch_mutex);

3490 3491 3492 3493 3494
	down_write(&rbd_dev->lock_rwsem);
	if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
		rbd_reacquire_lock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);

3495 3496
	ret = rbd_dev_refresh(rbd_dev);
	if (ret)
3497
		rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret);
3498 3499
}

3500
/*
3501 3502
 * Synchronous osd object method call.  Returns the number of bytes
 * returned in the outbound buffer, or a negative error code.
3503 3504
 */
static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
3505 3506
			     struct ceph_object_id *oid,
			     struct ceph_object_locator *oloc,
3507
			     const char *method_name,
3508
			     const void *outbound,
3509
			     size_t outbound_size,
3510
			     void *inbound,
3511
			     size_t inbound_size)
3512
{
3513 3514 3515
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct page *req_page = NULL;
	struct page *reply_page;
3516 3517 3518
	int ret;

	/*
3519 3520 3521 3522 3523
	 * Method calls are ultimately read operations.  The result
	 * should placed into the inbound buffer provided.  They
	 * also supply outbound data--parameters for the object
	 * method.  Currently if this is present it will be a
	 * snapshot id.
3524
	 */
3525 3526 3527
	if (outbound) {
		if (outbound_size > PAGE_SIZE)
			return -E2BIG;
3528

3529 3530 3531
		req_page = alloc_page(GFP_KERNEL);
		if (!req_page)
			return -ENOMEM;
3532

3533
		memcpy(page_address(req_page), outbound, outbound_size);
3534
	}
3535

3536 3537 3538 3539 3540 3541
	reply_page = alloc_page(GFP_KERNEL);
	if (!reply_page) {
		if (req_page)
			__free_page(req_page);
		return -ENOMEM;
	}
3542

3543 3544 3545 3546 3547 3548 3549
	ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name,
			     CEPH_OSD_FLAG_READ, req_page, outbound_size,
			     reply_page, &inbound_size);
	if (!ret) {
		memcpy(inbound, page_address(reply_page), inbound_size);
		ret = inbound_size;
	}
3550

3551 3552 3553
	if (req_page)
		__free_page(req_page);
	__free_page(reply_page);
3554 3555 3556
	return ret;
}

3557 3558 3559
/*
 * lock_rwsem must be held for read
 */
3560
static int rbd_wait_state_locked(struct rbd_device *rbd_dev, bool may_acquire)
3561 3562
{
	DEFINE_WAIT(wait);
3563
	unsigned long timeout;
3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575
	int ret = 0;

	if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags))
		return -EBLACKLISTED;

	if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
		return 0;

	if (!may_acquire) {
		rbd_warn(rbd_dev, "exclusive lock required");
		return -EROFS;
	}
3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586

	do {
		/*
		 * Note the use of mod_delayed_work() in rbd_acquire_lock()
		 * and cancel_delayed_work() in wake_requests().
		 */
		dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev);
		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
		prepare_to_wait_exclusive(&rbd_dev->lock_waitq, &wait,
					  TASK_UNINTERRUPTIBLE);
		up_read(&rbd_dev->lock_rwsem);
3587 3588
		timeout = schedule_timeout(ceph_timeout_jiffies(
						rbd_dev->opts->lock_timeout));
3589
		down_read(&rbd_dev->lock_rwsem);
3590 3591 3592 3593
		if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) {
			ret = -EBLACKLISTED;
			break;
		}
3594 3595 3596 3597 3598
		if (!timeout) {
			rbd_warn(rbd_dev, "timed out waiting for lock");
			ret = -ETIMEDOUT;
			break;
		}
3599
	} while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED);
3600

3601
	finish_wait(&rbd_dev->lock_waitq, &wait);
3602
	return ret;
3603 3604
}

C
Christoph Hellwig 已提交
3605
static void rbd_queue_workfn(struct work_struct *work)
A
Alex Elder 已提交
3606
{
C
Christoph Hellwig 已提交
3607 3608
	struct request *rq = blk_mq_rq_from_pdu(work);
	struct rbd_device *rbd_dev = rq->q->queuedata;
I
Ilya Dryomov 已提交
3609
	struct rbd_img_request *img_request;
3610
	struct ceph_snap_context *snapc = NULL;
I
Ilya Dryomov 已提交
3611 3612
	u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
	u64 length = blk_rq_bytes(rq);
G
Guangliang Zhao 已提交
3613
	enum obj_operation_type op_type;
3614
	u64 mapping_size;
I
Ilya Dryomov 已提交
3615
	bool must_be_locked;
A
Alex Elder 已提交
3616 3617
	int result;

3618 3619
	switch (req_op(rq)) {
	case REQ_OP_DISCARD:
3620
	case REQ_OP_WRITE_ZEROES:
3621
		op_type = OBJ_OP_DISCARD;
3622 3623
		break;
	case REQ_OP_WRITE:
G
Guangliang Zhao 已提交
3624
		op_type = OBJ_OP_WRITE;
3625 3626
		break;
	case REQ_OP_READ:
G
Guangliang Zhao 已提交
3627
		op_type = OBJ_OP_READ;
3628 3629 3630 3631 3632 3633
		break;
	default:
		dout("%s: non-fs request type %d\n", __func__, req_op(rq));
		result = -EIO;
		goto err;
	}
G
Guangliang Zhao 已提交
3634

I
Ilya Dryomov 已提交
3635
	/* Ignore/skip any zero-length requests */
A
Alex Elder 已提交
3636

I
Ilya Dryomov 已提交
3637 3638 3639 3640 3641
	if (!length) {
		dout("%s: zero-length request\n", __func__);
		result = 0;
		goto err_rq;
	}
A
Alex Elder 已提交
3642

3643 3644
	rbd_assert(op_type == OBJ_OP_READ ||
		   rbd_dev->spec->snap_id == CEPH_NOSNAP);
A
Alex Elder 已提交
3645

I
Ilya Dryomov 已提交
3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657
	/*
	 * Quit early if the mapped snapshot no longer exists.  It's
	 * still possible the snapshot will have disappeared by the
	 * time our request arrives at the osd, but there's no sense in
	 * sending it if we already know.
	 */
	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
		dout("request for non-existent snapshot");
		rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
		result = -ENXIO;
		goto err_rq;
	}
A
Alex Elder 已提交
3658

I
Ilya Dryomov 已提交
3659 3660 3661 3662 3663 3664
	if (offset && length > U64_MAX - offset + 1) {
		rbd_warn(rbd_dev, "bad request range (%llu~%llu)", offset,
			 length);
		result = -EINVAL;
		goto err_rq;	/* Shouldn't happen */
	}
A
Alex Elder 已提交
3665

C
Christoph Hellwig 已提交
3666 3667
	blk_mq_start_request(rq);

3668 3669
	down_read(&rbd_dev->header_rwsem);
	mapping_size = rbd_dev->mapping.size;
G
Guangliang Zhao 已提交
3670
	if (op_type != OBJ_OP_READ) {
3671 3672 3673 3674 3675 3676
		snapc = rbd_dev->header.snapc;
		ceph_get_snap_context(snapc);
	}
	up_read(&rbd_dev->header_rwsem);

	if (offset + length > mapping_size) {
I
Ilya Dryomov 已提交
3677
		rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
3678
			 length, mapping_size);
I
Ilya Dryomov 已提交
3679 3680 3681
		result = -EIO;
		goto err_rq;
	}
A
Alex Elder 已提交
3682

I
Ilya Dryomov 已提交
3683 3684 3685
	must_be_locked =
	    (rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK) &&
	    (op_type != OBJ_OP_READ || rbd_dev->opts->lock_on_read);
3686 3687
	if (must_be_locked) {
		down_read(&rbd_dev->lock_rwsem);
3688 3689 3690
		result = rbd_wait_state_locked(rbd_dev,
					       !rbd_dev->opts->exclusive);
		if (result)
3691
			goto err_unlock;
3692 3693
	}

3694
	img_request = rbd_img_request_create(rbd_dev, op_type, snapc);
I
Ilya Dryomov 已提交
3695 3696
	if (!img_request) {
		result = -ENOMEM;
3697
		goto err_unlock;
I
Ilya Dryomov 已提交
3698 3699
	}
	img_request->rq = rq;
3700
	snapc = NULL; /* img_request consumes a ref */
A
Alex Elder 已提交
3701

3702
	if (op_type == OBJ_OP_DISCARD)
3703
		result = rbd_img_fill_nodata(img_request, offset, length);
3704
	else
3705 3706
		result = rbd_img_fill_from_bio(img_request, offset, length,
					       rq->bio);
I
Ilya Dryomov 已提交
3707 3708
	if (result)
		goto err_img_request;
A
Alex Elder 已提交
3709

3710
	rbd_img_request_submit(img_request);
3711 3712
	if (must_be_locked)
		up_read(&rbd_dev->lock_rwsem);
I
Ilya Dryomov 已提交
3713
	return;
A
Alex Elder 已提交
3714

I
Ilya Dryomov 已提交
3715 3716
err_img_request:
	rbd_img_request_put(img_request);
3717 3718 3719
err_unlock:
	if (must_be_locked)
		up_read(&rbd_dev->lock_rwsem);
I
Ilya Dryomov 已提交
3720 3721 3722
err_rq:
	if (result)
		rbd_warn(rbd_dev, "%s %llx at %llx result %d",
G
Guangliang Zhao 已提交
3723
			 obj_op_name(op_type), length, offset, result);
3724
	ceph_put_snap_context(snapc);
C
Christoph Hellwig 已提交
3725
err:
3726
	blk_mq_end_request(rq, errno_to_blk_status(result));
I
Ilya Dryomov 已提交
3727
}
A
Alex Elder 已提交
3728

3729
static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
C
Christoph Hellwig 已提交
3730
		const struct blk_mq_queue_data *bd)
I
Ilya Dryomov 已提交
3731
{
C
Christoph Hellwig 已提交
3732 3733
	struct request *rq = bd->rq;
	struct work_struct *work = blk_mq_rq_to_pdu(rq);
A
Alex Elder 已提交
3734

C
Christoph Hellwig 已提交
3735
	queue_work(rbd_wq, work);
3736
	return BLK_STS_OK;
A
Alex Elder 已提交
3737 3738
}

3739 3740
static void rbd_free_disk(struct rbd_device *rbd_dev)
{
3741 3742 3743
	blk_cleanup_queue(rbd_dev->disk->queue);
	blk_mq_free_tag_set(&rbd_dev->tag_set);
	put_disk(rbd_dev->disk);
3744
	rbd_dev->disk = NULL;
3745 3746
}

3747
static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3748 3749 3750
			     struct ceph_object_id *oid,
			     struct ceph_object_locator *oloc,
			     void *buf, int buf_len)
3751 3752

{
3753 3754 3755 3756
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_osd_request *req;
	struct page **pages;
	int num_pages = calc_pages_for(0, buf_len);
3757 3758
	int ret;

3759 3760 3761
	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
	if (!req)
		return -ENOMEM;
3762

3763 3764 3765
	ceph_oid_copy(&req->r_base_oid, oid);
	ceph_oloc_copy(&req->r_base_oloc, oloc);
	req->r_flags = CEPH_OSD_FLAG_READ;
A
Alex Elder 已提交
3766

3767
	ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
3768
	if (ret)
3769
		goto out_req;
3770

3771 3772 3773 3774 3775
	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
	if (IS_ERR(pages)) {
		ret = PTR_ERR(pages);
		goto out_req;
	}
3776

3777 3778 3779 3780 3781 3782 3783 3784
	osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0);
	osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false,
					 true);

	ceph_osdc_start_request(osdc, req, false);
	ret = ceph_osdc_wait_request(osdc, req);
	if (ret >= 0)
		ceph_copy_from_page_vector(pages, buf, 0, ret);
3785

3786 3787
out_req:
	ceph_osdc_put_request(req);
3788 3789 3790
	return ret;
}

3791
/*
A
Alex Elder 已提交
3792 3793 3794
 * Read the complete header for the given rbd device.  On successful
 * return, the rbd_dev->header field will contain up-to-date
 * information about the image.
3795
 */
3796
static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3797
{
3798
	struct rbd_image_header_ondisk *ondisk = NULL;
3799
	u32 snap_count = 0;
3800 3801 3802
	u64 names_size = 0;
	u32 want_count;
	int ret;
3803

A
Alex Elder 已提交
3804
	/*
3805 3806 3807 3808 3809
	 * The complete header will include an array of its 64-bit
	 * snapshot ids, followed by the names of those snapshots as
	 * a contiguous block of NUL-terminated strings.  Note that
	 * the number of snapshots could change by the time we read
	 * it in, in which case we re-read it.
A
Alex Elder 已提交
3810
	 */
3811 3812 3813 3814 3815 3816 3817 3818 3819 3820
	do {
		size_t size;

		kfree(ondisk);

		size = sizeof (*ondisk);
		size += snap_count * sizeof (struct rbd_image_snap_ondisk);
		size += names_size;
		ondisk = kmalloc(size, GFP_KERNEL);
		if (!ondisk)
A
Alex Elder 已提交
3821
			return -ENOMEM;
3822

3823 3824
		ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid,
					&rbd_dev->header_oloc, ondisk, size);
3825
		if (ret < 0)
A
Alex Elder 已提交
3826
			goto out;
A
Alex Elder 已提交
3827
		if ((size_t)ret < size) {
3828
			ret = -ENXIO;
A
Alex Elder 已提交
3829 3830
			rbd_warn(rbd_dev, "short header read (want %zd got %d)",
				size, ret);
A
Alex Elder 已提交
3831
			goto out;
3832 3833 3834
		}
		if (!rbd_dev_ondisk_valid(ondisk)) {
			ret = -ENXIO;
A
Alex Elder 已提交
3835
			rbd_warn(rbd_dev, "invalid header");
A
Alex Elder 已提交
3836
			goto out;
3837
		}
3838

3839 3840 3841 3842
		names_size = le64_to_cpu(ondisk->snap_names_len);
		want_count = snap_count;
		snap_count = le32_to_cpu(ondisk->snap_count);
	} while (snap_count != want_count);
A
Alex Elder 已提交
3843

A
Alex Elder 已提交
3844 3845
	ret = rbd_header_from_disk(rbd_dev, ondisk);
out:
3846 3847 3848
	kfree(ondisk);

	return ret;
3849 3850
}

3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869
/*
 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
 * has disappeared from the (just updated) snapshot context.
 */
static void rbd_exists_validate(struct rbd_device *rbd_dev)
{
	u64 snap_id;

	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
		return;

	snap_id = rbd_dev->spec->snap_id;
	if (snap_id == CEPH_NOSNAP)
		return;

	if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
		clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
}

3870 3871 3872 3873 3874
static void rbd_dev_update_size(struct rbd_device *rbd_dev)
{
	sector_t size;

	/*
I
Ilya Dryomov 已提交
3875 3876 3877
	 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't
	 * try to update its size.  If REMOVING is set, updating size
	 * is just useless work since the device can't be opened.
3878
	 */
I
Ilya Dryomov 已提交
3879 3880
	if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) &&
	    !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
3881 3882 3883 3884 3885 3886 3887
		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
		dout("setting size to %llu sectors", (unsigned long long)size);
		set_capacity(rbd_dev->disk, size);
		revalidate_disk(rbd_dev->disk);
	}
}

A
Alex Elder 已提交
3888
static int rbd_dev_refresh(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
3889
{
3890
	u64 mapping_size;
A
Alex Elder 已提交
3891 3892
	int ret;

3893
	down_write(&rbd_dev->header_rwsem);
3894
	mapping_size = rbd_dev->mapping.size;
3895 3896

	ret = rbd_dev_header_info(rbd_dev);
3897
	if (ret)
3898
		goto out;
3899

3900 3901 3902 3903 3904 3905 3906
	/*
	 * If there is a parent, see if it has disappeared due to the
	 * mapped image getting flattened.
	 */
	if (rbd_dev->parent) {
		ret = rbd_dev_v2_parent_info(rbd_dev);
		if (ret)
3907
			goto out;
3908 3909
	}

3910
	if (rbd_dev->spec->snap_id == CEPH_NOSNAP) {
3911
		rbd_dev->mapping.size = rbd_dev->header.image_size;
3912 3913 3914 3915
	} else {
		/* validate mapped snapshot's EXISTS flag */
		rbd_exists_validate(rbd_dev);
	}
3916

3917
out:
3918
	up_write(&rbd_dev->header_rwsem);
3919
	if (!ret && mapping_size != rbd_dev->mapping.size)
3920
		rbd_dev_update_size(rbd_dev);
A
Alex Elder 已提交
3921

3922
	return ret;
A
Alex Elder 已提交
3923 3924
}

3925 3926
static int rbd_init_request(struct blk_mq_tag_set *set, struct request *rq,
		unsigned int hctx_idx, unsigned int numa_node)
C
Christoph Hellwig 已提交
3927 3928 3929 3930 3931 3932 3933
{
	struct work_struct *work = blk_mq_rq_to_pdu(rq);

	INIT_WORK(work, rbd_queue_workfn);
	return 0;
}

3934
static const struct blk_mq_ops rbd_mq_ops = {
C
Christoph Hellwig 已提交
3935 3936 3937 3938
	.queue_rq	= rbd_queue_rq,
	.init_request	= rbd_init_request,
};

3939 3940 3941 3942
static int rbd_init_disk(struct rbd_device *rbd_dev)
{
	struct gendisk *disk;
	struct request_queue *q;
3943 3944
	unsigned int objset_bytes =
	    rbd_dev->layout.object_size * rbd_dev->layout.stripe_count;
C
Christoph Hellwig 已提交
3945
	int err;
3946 3947

	/* create gendisk info */
3948 3949 3950
	disk = alloc_disk(single_major ?
			  (1 << RBD_SINGLE_MAJOR_PART_SHIFT) :
			  RBD_MINORS_PER_MAJOR);
3951
	if (!disk)
A
Alex Elder 已提交
3952
		return -ENOMEM;
3953

A
Alex Elder 已提交
3954
	snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
A
Alex Elder 已提交
3955
		 rbd_dev->dev_id);
3956
	disk->major = rbd_dev->major;
3957
	disk->first_minor = rbd_dev->minor;
3958 3959
	if (single_major)
		disk->flags |= GENHD_FL_EXT_DEVT;
3960 3961 3962
	disk->fops = &rbd_bd_ops;
	disk->private_data = rbd_dev;

C
Christoph Hellwig 已提交
3963 3964
	memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
	rbd_dev->tag_set.ops = &rbd_mq_ops;
I
Ilya Dryomov 已提交
3965
	rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
C
Christoph Hellwig 已提交
3966
	rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
I
Ilya Dryomov 已提交
3967
	rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
C
Christoph Hellwig 已提交
3968 3969 3970 3971 3972
	rbd_dev->tag_set.nr_hw_queues = 1;
	rbd_dev->tag_set.cmd_size = sizeof(struct work_struct);

	err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
	if (err)
3973
		goto out_disk;
3974

C
Christoph Hellwig 已提交
3975 3976 3977 3978 3979 3980
	q = blk_mq_init_queue(&rbd_dev->tag_set);
	if (IS_ERR(q)) {
		err = PTR_ERR(q);
		goto out_tag_set;
	}

3981
	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
3982
	/* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
A
Alex Elder 已提交
3983

3984
	blk_queue_max_hw_sectors(q, objset_bytes >> SECTOR_SHIFT);
I
Ilya Dryomov 已提交
3985
	q->limits.max_sectors = queue_max_hw_sectors(q);
3986
	blk_queue_max_segments(q, USHRT_MAX);
3987
	blk_queue_max_segment_size(q, UINT_MAX);
3988 3989
	blk_queue_io_min(q, objset_bytes);
	blk_queue_io_opt(q, objset_bytes);
3990

I
Ilya Dryomov 已提交
3991 3992 3993 3994 3995 3996
	if (rbd_dev->opts->trim) {
		blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
		q->limits.discard_granularity = objset_bytes;
		blk_queue_max_discard_sectors(q, objset_bytes >> SECTOR_SHIFT);
		blk_queue_max_write_zeroes_sectors(q, objset_bytes >> SECTOR_SHIFT);
	}
3997

3998
	if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
3999
		q->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES;
4000

4001 4002 4003 4004 4005
	/*
	 * disk_release() expects a queue ref from add_disk() and will
	 * put it.  Hold an extra ref until add_disk() is called.
	 */
	WARN_ON(!blk_get_queue(q));
4006 4007 4008 4009 4010 4011
	disk->queue = q;
	q->queuedata = rbd_dev;

	rbd_dev->disk = disk;

	return 0;
C
Christoph Hellwig 已提交
4012 4013
out_tag_set:
	blk_mq_free_tag_set(&rbd_dev->tag_set);
4014 4015
out_disk:
	put_disk(disk);
C
Christoph Hellwig 已提交
4016
	return err;
4017 4018
}

4019 4020 4021 4022
/*
  sysfs
*/

A
Alex Elder 已提交
4023 4024 4025 4026 4027
static struct rbd_device *dev_to_rbd_dev(struct device *dev)
{
	return container_of(dev, struct rbd_device, dev);
}

4028 4029 4030
static ssize_t rbd_size_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4031
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4032

A
Alex Elder 已提交
4033 4034
	return sprintf(buf, "%llu\n",
		(unsigned long long)rbd_dev->mapping.size);
4035 4036
}

A
Alex Elder 已提交
4037 4038 4039 4040 4041 4042 4043 4044 4045 4046
/*
 * Note this shows the features for whatever's mapped, which is not
 * necessarily the base image.
 */
static ssize_t rbd_features_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "0x%016llx\n",
A
Alex Elder 已提交
4047
			(unsigned long long)rbd_dev->mapping.features);
A
Alex Elder 已提交
4048 4049
}

4050 4051 4052
static ssize_t rbd_major_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4053
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4054

A
Alex Elder 已提交
4055 4056 4057 4058
	if (rbd_dev->major)
		return sprintf(buf, "%d\n", rbd_dev->major);

	return sprintf(buf, "(none)\n");
4059 4060 4061 4062 4063 4064
}

static ssize_t rbd_minor_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
A
Alex Elder 已提交
4065

4066
	return sprintf(buf, "%d\n", rbd_dev->minor);
4067 4068
}

4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079
static ssize_t rbd_client_addr_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
	struct ceph_entity_addr *client_addr =
	    ceph_client_addr(rbd_dev->rbd_client->client);

	return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr,
		       le32_to_cpu(client_addr->nonce));
}

4080 4081
static ssize_t rbd_client_id_show(struct device *dev,
				  struct device_attribute *attr, char *buf)
4082
{
A
Alex Elder 已提交
4083
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4084

4085
	return sprintf(buf, "client%lld\n",
4086
		       ceph_client_gid(rbd_dev->rbd_client->client));
4087 4088
}

4089 4090 4091 4092 4093 4094 4095 4096
static ssize_t rbd_cluster_fsid_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid);
}

4097 4098 4099 4100 4101 4102
static ssize_t rbd_config_info_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%s\n", rbd_dev->config_info);
4103 4104
}

4105 4106
static ssize_t rbd_pool_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
4107
{
A
Alex Elder 已提交
4108
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4109

4110
	return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
4111 4112
}

4113 4114 4115 4116 4117
static ssize_t rbd_pool_id_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

4118
	return sprintf(buf, "%llu\n",
A
Alex Elder 已提交
4119
			(unsigned long long) rbd_dev->spec->pool_id);
4120 4121
}

4122 4123 4124
static ssize_t rbd_name_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4125
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4126

A
Alex Elder 已提交
4127 4128 4129 4130
	if (rbd_dev->spec->image_name)
		return sprintf(buf, "%s\n", rbd_dev->spec->image_name);

	return sprintf(buf, "(unknown)\n");
4131 4132
}

A
Alex Elder 已提交
4133 4134 4135 4136 4137
static ssize_t rbd_image_id_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

4138
	return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
A
Alex Elder 已提交
4139 4140
}

A
Alex Elder 已提交
4141 4142 4143 4144
/*
 * Shows the name of the currently-mapped snapshot (or
 * RBD_SNAP_HEAD_NAME for the base image).
 */
4145 4146 4147 4148
static ssize_t rbd_snap_show(struct device *dev,
			     struct device_attribute *attr,
			     char *buf)
{
A
Alex Elder 已提交
4149
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4150

4151
	return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
4152 4153
}

4154 4155 4156 4157 4158 4159 4160 4161
static ssize_t rbd_snap_id_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id);
}

4162
/*
4163 4164 4165
 * For a v2 image, shows the chain of parent images, separated by empty
 * lines.  For v1 images or if there is no parent, shows "(no parent
 * image)".
4166 4167
 */
static ssize_t rbd_parent_show(struct device *dev,
4168 4169
			       struct device_attribute *attr,
			       char *buf)
4170 4171
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4172
	ssize_t count = 0;
4173

4174
	if (!rbd_dev->parent)
4175 4176
		return sprintf(buf, "(no parent image)\n");

4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192
	for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
		struct rbd_spec *spec = rbd_dev->parent_spec;

		count += sprintf(&buf[count], "%s"
			    "pool_id %llu\npool_name %s\n"
			    "image_id %s\nimage_name %s\n"
			    "snap_id %llu\nsnap_name %s\n"
			    "overlap %llu\n",
			    !count ? "" : "\n", /* first? */
			    spec->pool_id, spec->pool_name,
			    spec->image_id, spec->image_name ?: "(unknown)",
			    spec->snap_id, spec->snap_name,
			    rbd_dev->parent_overlap);
	}

	return count;
4193 4194
}

4195 4196 4197 4198 4199
static ssize_t rbd_image_refresh(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf,
				 size_t size)
{
A
Alex Elder 已提交
4200
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4201
	int ret;
4202

A
Alex Elder 已提交
4203
	ret = rbd_dev_refresh(rbd_dev);
4204
	if (ret)
4205
		return ret;
4206

4207
	return size;
4208
}
4209

4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225
static DEVICE_ATTR(size, 0444, rbd_size_show, NULL);
static DEVICE_ATTR(features, 0444, rbd_features_show, NULL);
static DEVICE_ATTR(major, 0444, rbd_major_show, NULL);
static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL);
static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL);
static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL);
static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL);
static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL);
static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL);
static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL);
static DEVICE_ATTR(name, 0444, rbd_name_show, NULL);
static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL);
static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh);
static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL);
static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL);
static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL);
4226 4227 4228

static struct attribute *rbd_attrs[] = {
	&dev_attr_size.attr,
A
Alex Elder 已提交
4229
	&dev_attr_features.attr,
4230
	&dev_attr_major.attr,
4231
	&dev_attr_minor.attr,
4232
	&dev_attr_client_addr.attr,
4233
	&dev_attr_client_id.attr,
4234
	&dev_attr_cluster_fsid.attr,
4235
	&dev_attr_config_info.attr,
4236
	&dev_attr_pool.attr,
4237
	&dev_attr_pool_id.attr,
4238
	&dev_attr_name.attr,
A
Alex Elder 已提交
4239
	&dev_attr_image_id.attr,
4240
	&dev_attr_current_snap.attr,
4241
	&dev_attr_snap_id.attr,
4242
	&dev_attr_parent.attr,
4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255
	&dev_attr_refresh.attr,
	NULL
};

static struct attribute_group rbd_attr_group = {
	.attrs = rbd_attrs,
};

static const struct attribute_group *rbd_attr_groups[] = {
	&rbd_attr_group,
	NULL
};

4256
static void rbd_dev_release(struct device *dev);
4257

4258
static const struct device_type rbd_device_type = {
4259 4260
	.name		= "rbd",
	.groups		= rbd_attr_groups,
4261
	.release	= rbd_dev_release,
4262 4263
};

4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284
static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
{
	kref_get(&spec->kref);

	return spec;
}

static void rbd_spec_free(struct kref *kref);
static void rbd_spec_put(struct rbd_spec *spec)
{
	if (spec)
		kref_put(&spec->kref, rbd_spec_free);
}

static struct rbd_spec *rbd_spec_alloc(void)
{
	struct rbd_spec *spec;

	spec = kzalloc(sizeof (*spec), GFP_KERNEL);
	if (!spec)
		return NULL;
4285 4286 4287

	spec->pool_id = CEPH_NOPOOL;
	spec->snap_id = CEPH_NOSNAP;
4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303
	kref_init(&spec->kref);

	return spec;
}

static void rbd_spec_free(struct kref *kref)
{
	struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);

	kfree(spec->pool_name);
	kfree(spec->image_id);
	kfree(spec->image_name);
	kfree(spec->snap_name);
	kfree(spec);
}

4304
static void rbd_dev_free(struct rbd_device *rbd_dev)
4305
{
4306
	WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED);
4307
	WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED);
4308

4309
	ceph_oid_destroy(&rbd_dev->header_oid);
4310
	ceph_oloc_destroy(&rbd_dev->header_oloc);
4311
	kfree(rbd_dev->config_info);
4312

4313 4314 4315 4316
	rbd_put_client(rbd_dev->rbd_client);
	rbd_spec_put(rbd_dev->spec);
	kfree(rbd_dev->opts);
	kfree(rbd_dev);
4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329
}

static void rbd_dev_release(struct device *dev)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
	bool need_put = !!rbd_dev->opts;

	if (need_put) {
		destroy_workqueue(rbd_dev->task_wq);
		ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
	}

	rbd_dev_free(rbd_dev);
4330 4331 4332 4333 4334 4335 4336 4337 4338 4339

	/*
	 * This is racy, but way better than putting module outside of
	 * the release callback.  The race window is pretty small, so
	 * doing something similar to dm (dm-builtin.c) is overkill.
	 */
	if (need_put)
		module_put(THIS_MODULE);
}

4340 4341
static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc,
					   struct rbd_spec *spec)
4342 4343 4344
{
	struct rbd_device *rbd_dev;

4345
	rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
4346 4347 4348 4349 4350 4351 4352
	if (!rbd_dev)
		return NULL;

	spin_lock_init(&rbd_dev->lock);
	INIT_LIST_HEAD(&rbd_dev->node);
	init_rwsem(&rbd_dev->header_rwsem);

4353
	rbd_dev->header.data_pool_id = CEPH_NOPOOL;
4354
	ceph_oid_init(&rbd_dev->header_oid);
4355
	rbd_dev->header_oloc.pool = spec->pool_id;
4356

4357 4358 4359 4360
	mutex_init(&rbd_dev->watch_mutex);
	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
	INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch);

4361 4362 4363 4364 4365 4366 4367 4368
	init_rwsem(&rbd_dev->lock_rwsem);
	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
	INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock);
	INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock);
	INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock);
	INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work);
	init_waitqueue_head(&rbd_dev->lock_waitq);

4369 4370 4371 4372 4373
	rbd_dev->dev.bus = &rbd_bus_type;
	rbd_dev->dev.type = &rbd_device_type;
	rbd_dev->dev.parent = &rbd_root_dev;
	device_initialize(&rbd_dev->dev);

4374
	rbd_dev->rbd_client = rbdc;
4375
	rbd_dev->spec = spec;
4376

4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406
	return rbd_dev;
}

/*
 * Create a mapping rbd_dev.
 */
static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
					 struct rbd_spec *spec,
					 struct rbd_options *opts)
{
	struct rbd_device *rbd_dev;

	rbd_dev = __rbd_dev_create(rbdc, spec);
	if (!rbd_dev)
		return NULL;

	rbd_dev->opts = opts;

	/* get an id and fill in device name */
	rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0,
					 minor_to_rbd_dev_id(1 << MINORBITS),
					 GFP_KERNEL);
	if (rbd_dev->dev_id < 0)
		goto fail_rbd_dev;

	sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id);
	rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM,
						   rbd_dev->name);
	if (!rbd_dev->task_wq)
		goto fail_dev_id;
4407

4408 4409
	/* we have a ref from do_rbd_add() */
	__module_get(THIS_MODULE);
4410

4411
	dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id);
4412
	return rbd_dev;
4413 4414 4415 4416 4417 4418

fail_dev_id:
	ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
fail_rbd_dev:
	rbd_dev_free(rbd_dev);
	return NULL;
4419 4420 4421 4422
}

static void rbd_dev_destroy(struct rbd_device *rbd_dev)
{
4423 4424
	if (rbd_dev)
		put_device(&rbd_dev->dev);
4425 4426
}

4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441
/*
 * Get the size and object order for an image snapshot, or if
 * snap_id is CEPH_NOSNAP, gets this information for the base
 * image.
 */
static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u8 *order, u64 *snap_size)
{
	__le64 snapid = cpu_to_le64(snap_id);
	int ret;
	struct {
		u8 order;
		__le64 size;
	} __attribute__ ((packed)) size_buf = { 0 };

4442 4443 4444 4445
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_size",
				  &snapid, sizeof(snapid),
				  &size_buf, sizeof(size_buf));
4446
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4447 4448
	if (ret < 0)
		return ret;
4449 4450
	if (ret < sizeof (size_buf))
		return -ERANGE;
4451

J
Josh Durgin 已提交
4452
	if (order) {
4453
		*order = size_buf.order;
J
Josh Durgin 已提交
4454 4455
		dout("  order %u", (unsigned int)*order);
	}
4456 4457
	*snap_size = le64_to_cpu(size_buf.size);

J
Josh Durgin 已提交
4458 4459
	dout("  snap_id 0x%016llx snap_size = %llu\n",
		(unsigned long long)snap_id,
4460
		(unsigned long long)*snap_size);
4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471

	return 0;
}

static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
{
	return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
					&rbd_dev->header.obj_order,
					&rbd_dev->header.image_size);
}

4472 4473 4474 4475 4476 4477 4478 4479 4480 4481
static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
{
	void *reply_buf;
	int ret;
	void *p;

	reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
	if (!reply_buf)
		return -ENOMEM;

4482 4483 4484
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_object_prefix",
				  NULL, 0, reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
4485
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4486 4487 4488 4489 4490
	if (ret < 0)
		goto out;

	p = reply_buf;
	rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
4491 4492
						p + ret, NULL, GFP_NOIO);
	ret = 0;
4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505

	if (IS_ERR(rbd_dev->header.object_prefix)) {
		ret = PTR_ERR(rbd_dev->header.object_prefix);
		rbd_dev->header.object_prefix = NULL;
	} else {
		dout("  object_prefix = %s\n", rbd_dev->header.object_prefix);
	}
out:
	kfree(reply_buf);

	return ret;
}

4506 4507 4508 4509 4510 4511 4512
static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
		u64 *snap_features)
{
	__le64 snapid = cpu_to_le64(snap_id);
	struct {
		__le64 features;
		__le64 incompat;
4513
	} __attribute__ ((packed)) features_buf = { 0 };
4514
	u64 unsup;
4515 4516
	int ret;

4517 4518 4519 4520
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_features",
				  &snapid, sizeof(snapid),
				  &features_buf, sizeof(features_buf));
4521
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4522 4523
	if (ret < 0)
		return ret;
4524 4525
	if (ret < sizeof (features_buf))
		return -ERANGE;
A
Alex Elder 已提交
4526

4527 4528 4529 4530
	unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED;
	if (unsup) {
		rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx",
			 unsup);
A
Alex Elder 已提交
4531
		return -ENXIO;
4532
	}
A
Alex Elder 已提交
4533

4534 4535 4536
	*snap_features = le64_to_cpu(features_buf.features);

	dout("  snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
4537 4538 4539
		(unsigned long long)snap_id,
		(unsigned long long)*snap_features,
		(unsigned long long)le64_to_cpu(features_buf.incompat));
4540 4541 4542 4543 4544 4545 4546 4547 4548 4549

	return 0;
}

static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
{
	return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
						&rbd_dev->header.features);
}

4550 4551 4552 4553 4554 4555 4556 4557
static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
{
	struct rbd_spec *parent_spec;
	size_t size;
	void *reply_buf = NULL;
	__le64 snapid;
	void *p;
	void *end;
A
Alex Elder 已提交
4558
	u64 pool_id;
4559
	char *image_id;
4560
	u64 snap_id;
4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577
	u64 overlap;
	int ret;

	parent_spec = rbd_spec_alloc();
	if (!parent_spec)
		return -ENOMEM;

	size = sizeof (__le64) +				/* pool_id */
		sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX +	/* image_id */
		sizeof (__le64) +				/* snap_id */
		sizeof (__le64);				/* overlap */
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf) {
		ret = -ENOMEM;
		goto out_err;
	}

4578
	snapid = cpu_to_le64(rbd_dev->spec->snap_id);
4579 4580 4581
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_parent",
				  &snapid, sizeof(snapid), reply_buf, size);
4582
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4583 4584 4585 4586
	if (ret < 0)
		goto out_err;

	p = reply_buf;
4587 4588
	end = reply_buf + ret;
	ret = -ERANGE;
A
Alex Elder 已提交
4589
	ceph_decode_64_safe(&p, end, pool_id, out_err);
4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606
	if (pool_id == CEPH_NOPOOL) {
		/*
		 * Either the parent never existed, or we have
		 * record of it but the image got flattened so it no
		 * longer has a parent.  When the parent of a
		 * layered image disappears we immediately set the
		 * overlap to 0.  The effect of this is that all new
		 * requests will be treated as if the image had no
		 * parent.
		 */
		if (rbd_dev->parent_overlap) {
			rbd_dev->parent_overlap = 0;
			rbd_dev_parent_put(rbd_dev);
			pr_info("%s: clone image has been flattened\n",
				rbd_dev->disk->disk_name);
		}

4607
		goto out;	/* No parent?  No problem. */
4608
	}
4609

4610 4611 4612
	/* The ceph file layout needs to fit pool id in 32 bits */

	ret = -EIO;
A
Alex Elder 已提交
4613
	if (pool_id > (u64)U32_MAX) {
4614
		rbd_warn(NULL, "parent pool id too large (%llu > %u)",
A
Alex Elder 已提交
4615
			(unsigned long long)pool_id, U32_MAX);
4616
		goto out_err;
A
Alex Elder 已提交
4617
	}
4618

A
Alex Elder 已提交
4619
	image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4620 4621 4622 4623
	if (IS_ERR(image_id)) {
		ret = PTR_ERR(image_id);
		goto out_err;
	}
4624
	ceph_decode_64_safe(&p, end, snap_id, out_err);
4625 4626
	ceph_decode_64_safe(&p, end, overlap, out_err);

4627 4628 4629 4630 4631 4632 4633 4634 4635
	/*
	 * The parent won't change (except when the clone is
	 * flattened, already handled that).  So we only need to
	 * record the parent spec we have not already done so.
	 */
	if (!rbd_dev->parent_spec) {
		parent_spec->pool_id = pool_id;
		parent_spec->image_id = image_id;
		parent_spec->snap_id = snap_id;
A
Alex Elder 已提交
4636 4637
		rbd_dev->parent_spec = parent_spec;
		parent_spec = NULL;	/* rbd_dev now owns this */
4638 4639
	} else {
		kfree(image_id);
4640 4641 4642
	}

	/*
4643 4644
	 * We always update the parent overlap.  If it's zero we issue
	 * a warning, as we will proceed as if there was no parent.
4645 4646 4647
	 */
	if (!overlap) {
		if (parent_spec) {
4648 4649 4650 4651
			/* refresh, careful to warn just once */
			if (rbd_dev->parent_overlap)
				rbd_warn(rbd_dev,
				    "clone now standalone (overlap became 0)");
4652
		} else {
4653 4654
			/* initial probe */
			rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
4655
		}
A
Alex Elder 已提交
4656
	}
4657 4658
	rbd_dev->parent_overlap = overlap;

4659 4660 4661 4662 4663 4664 4665 4666 4667
out:
	ret = 0;
out_err:
	kfree(reply_buf);
	rbd_spec_put(parent_spec);

	return ret;
}

4668 4669 4670 4671 4672 4673 4674 4675 4676 4677
static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
{
	struct {
		__le64 stripe_unit;
		__le64 stripe_count;
	} __attribute__ ((packed)) striping_info_buf = { 0 };
	size_t size = sizeof (striping_info_buf);
	void *p;
	int ret;

4678 4679 4680
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				&rbd_dev->header_oloc, "get_stripe_unit_count",
				NULL, 0, &striping_info_buf, size);
4681 4682 4683 4684 4685 4686 4687
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
	if (ret < 0)
		return ret;
	if (ret < size)
		return -ERANGE;

	p = &striping_info_buf;
I
Ilya Dryomov 已提交
4688 4689
	rbd_dev->header.stripe_unit = ceph_decode_64(&p);
	rbd_dev->header.stripe_count = ceph_decode_64(&p);
4690 4691 4692
	return 0;
}

4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710
static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev)
{
	__le64 data_pool_id;
	int ret;

	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_data_pool",
				  NULL, 0, &data_pool_id, sizeof(data_pool_id));
	if (ret < 0)
		return ret;
	if (ret < sizeof(data_pool_id))
		return -EBADMSG;

	rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id);
	WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL);
	return 0;
}

4711 4712
static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
{
4713
	CEPH_DEFINE_OID_ONSTACK(oid);
4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725
	size_t image_id_size;
	char *image_id;
	void *p;
	void *end;
	size_t size;
	void *reply_buf = NULL;
	size_t len = 0;
	char *image_name = NULL;
	int ret;

	rbd_assert(!rbd_dev->spec->image_name);

A
Alex Elder 已提交
4726 4727
	len = strlen(rbd_dev->spec->image_id);
	image_id_size = sizeof (__le32) + len;
4728 4729 4730 4731 4732
	image_id = kmalloc(image_id_size, GFP_KERNEL);
	if (!image_id)
		return NULL;

	p = image_id;
4733
	end = image_id + image_id_size;
4734
	ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
4735 4736 4737 4738 4739 4740

	size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf)
		goto out;

4741 4742 4743 4744
	ceph_oid_printf(&oid, "%s", RBD_DIRECTORY);
	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
				  "dir_get_name", image_id, image_id_size,
				  reply_buf, size);
4745 4746 4747
	if (ret < 0)
		goto out;
	p = reply_buf;
4748 4749
	end = reply_buf + ret;

4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761
	image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
	if (IS_ERR(image_name))
		image_name = NULL;
	else
		dout("%s: name is %s len is %zd\n", __func__, image_name, len);
out:
	kfree(reply_buf);
	kfree(image_id);

	return image_name;
}

4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791
static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
	const char *snap_name;
	u32 which = 0;

	/* Skip over names until we find the one we are looking for */

	snap_name = rbd_dev->header.snap_names;
	while (which < snapc->num_snaps) {
		if (!strcmp(name, snap_name))
			return snapc->snaps[which];
		snap_name += strlen(snap_name) + 1;
		which++;
	}
	return CEPH_NOSNAP;
}

static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
	u32 which;
	bool found = false;
	u64 snap_id;

	for (which = 0; !found && which < snapc->num_snaps; which++) {
		const char *snap_name;

		snap_id = snapc->snaps[which];
		snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4792 4793 4794 4795 4796 4797 4798
		if (IS_ERR(snap_name)) {
			/* ignore no-longer existing snapshots */
			if (PTR_ERR(snap_name) == -ENOENT)
				continue;
			else
				break;
		}
4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816
		found = !strcmp(name, snap_name);
		kfree(snap_name);
	}
	return found ? snap_id : CEPH_NOSNAP;
}

/*
 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
 * no snapshot by that name is found, or if an error occurs.
 */
static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	if (rbd_dev->image_format == 1)
		return rbd_v1_snap_id_by_name(rbd_dev, name);

	return rbd_v2_snap_id_by_name(rbd_dev, name);
}

4817
/*
4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844
 * An image being mapped will have everything but the snap id.
 */
static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
{
	struct rbd_spec *spec = rbd_dev->spec;

	rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
	rbd_assert(spec->image_id && spec->image_name);
	rbd_assert(spec->snap_name);

	if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
		u64 snap_id;

		snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
		if (snap_id == CEPH_NOSNAP)
			return -ENOENT;

		spec->snap_id = snap_id;
	} else {
		spec->snap_id = CEPH_NOSNAP;
	}

	return 0;
}

/*
 * A parent image will have all ids but none of the names.
4845
 *
4846 4847
 * All names in an rbd spec are dynamically allocated.  It's OK if we
 * can't figure out the name for an image id.
4848
 */
4849
static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
4850
{
4851 4852 4853 4854 4855
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct rbd_spec *spec = rbd_dev->spec;
	const char *pool_name;
	const char *image_name;
	const char *snap_name;
4856 4857
	int ret;

4858 4859 4860
	rbd_assert(spec->pool_id != CEPH_NOPOOL);
	rbd_assert(spec->image_id);
	rbd_assert(spec->snap_id != CEPH_NOSNAP);
4861

4862
	/* Get the pool name; we have to make our own copy of this */
4863

4864 4865 4866
	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
	if (!pool_name) {
		rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4867 4868
		return -EIO;
	}
4869 4870
	pool_name = kstrdup(pool_name, GFP_KERNEL);
	if (!pool_name)
4871 4872 4873 4874
		return -ENOMEM;

	/* Fetch the image name; tolerate failure here */

4875 4876
	image_name = rbd_dev_image_name(rbd_dev);
	if (!image_name)
A
Alex Elder 已提交
4877
		rbd_warn(rbd_dev, "unable to get image name");
4878

4879
	/* Fetch the snapshot name */
4880

4881
	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4882 4883
	if (IS_ERR(snap_name)) {
		ret = PTR_ERR(snap_name);
4884
		goto out_err;
4885 4886 4887 4888 4889
	}

	spec->pool_name = pool_name;
	spec->image_name = image_name;
	spec->snap_name = snap_name;
4890 4891

	return 0;
4892

4893
out_err:
4894 4895
	kfree(image_name);
	kfree(pool_name);
4896 4897 4898
	return ret;
}

A
Alex Elder 已提交
4899
static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922
{
	size_t size;
	int ret;
	void *reply_buf;
	void *p;
	void *end;
	u64 seq;
	u32 snap_count;
	struct ceph_snap_context *snapc;
	u32 i;

	/*
	 * We'll need room for the seq value (maximum snapshot id),
	 * snapshot count, and array of that many snapshot ids.
	 * For now we have a fixed upper limit on the number we're
	 * prepared to receive.
	 */
	size = sizeof (__le64) + sizeof (__le32) +
			RBD_MAX_SNAP_COUNT * sizeof (__le64);
	reply_buf = kzalloc(size, GFP_KERNEL);
	if (!reply_buf)
		return -ENOMEM;

4923 4924 4925
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_snapcontext",
				  NULL, 0, reply_buf, size);
4926
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4927 4928 4929 4930
	if (ret < 0)
		goto out;

	p = reply_buf;
4931 4932
	end = reply_buf + ret;
	ret = -ERANGE;
4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948
	ceph_decode_64_safe(&p, end, seq, out);
	ceph_decode_32_safe(&p, end, snap_count, out);

	/*
	 * Make sure the reported number of snapshot ids wouldn't go
	 * beyond the end of our buffer.  But before checking that,
	 * make sure the computed size of the snapshot context we
	 * allocate is representable in a size_t.
	 */
	if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
				 / sizeof (u64)) {
		ret = -EINVAL;
		goto out;
	}
	if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
		goto out;
4949
	ret = 0;
4950

4951
	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4952 4953 4954 4955 4956 4957 4958 4959
	if (!snapc) {
		ret = -ENOMEM;
		goto out;
	}
	snapc->seq = seq;
	for (i = 0; i < snap_count; i++)
		snapc->snaps[i] = ceph_decode_64(&p);

4960
	ceph_put_snap_context(rbd_dev->header.snapc);
4961 4962 4963
	rbd_dev->header.snapc = snapc;

	dout("  snap context seq = %llu, snap_count = %u\n",
4964
		(unsigned long long)seq, (unsigned int)snap_count);
4965 4966 4967
out:
	kfree(reply_buf);

4968
	return ret;
4969 4970
}

4971 4972
static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id)
A
Alex Elder 已提交
4973 4974 4975
{
	size_t size;
	void *reply_buf;
4976
	__le64 snapid;
A
Alex Elder 已提交
4977 4978 4979 4980 4981 4982 4983 4984 4985 4986
	int ret;
	void *p;
	void *end;
	char *snap_name;

	size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf)
		return ERR_PTR(-ENOMEM);

4987
	snapid = cpu_to_le64(snap_id);
4988 4989 4990
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_snapshot_name",
				  &snapid, sizeof(snapid), reply_buf, size);
4991
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4992 4993
	if (ret < 0) {
		snap_name = ERR_PTR(ret);
A
Alex Elder 已提交
4994
		goto out;
4995
	}
A
Alex Elder 已提交
4996 4997

	p = reply_buf;
4998
	end = reply_buf + ret;
A
Alex Elder 已提交
4999
	snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5000
	if (IS_ERR(snap_name))
A
Alex Elder 已提交
5001 5002
		goto out;

5003
	dout("  snap_id 0x%016llx snap_name = %s\n",
5004
		(unsigned long long)snap_id, snap_name);
A
Alex Elder 已提交
5005 5006 5007
out:
	kfree(reply_buf);

5008
	return snap_name;
A
Alex Elder 已提交
5009 5010
}

5011
static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
5012
{
5013
	bool first_time = rbd_dev->header.object_prefix == NULL;
A
Alex Elder 已提交
5014 5015
	int ret;

5016 5017
	ret = rbd_dev_v2_image_size(rbd_dev);
	if (ret)
5018
		return ret;
5019

5020 5021 5022
	if (first_time) {
		ret = rbd_dev_v2_header_onetime(rbd_dev);
		if (ret)
5023
			return ret;
5024 5025
	}

A
Alex Elder 已提交
5026
	ret = rbd_dev_v2_snap_context(rbd_dev);
5027 5028 5029 5030
	if (ret && first_time) {
		kfree(rbd_dev->header.object_prefix);
		rbd_dev->header.object_prefix = NULL;
	}
A
Alex Elder 已提交
5031 5032 5033 5034

	return ret;
}

5035 5036 5037 5038 5039 5040 5041 5042 5043 5044
static int rbd_dev_header_info(struct rbd_device *rbd_dev)
{
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));

	if (rbd_dev->image_format == 1)
		return rbd_dev_v1_header_info(rbd_dev);

	return rbd_dev_v2_header_info(rbd_dev);
}

5045 5046 5047
/*
 * Skips over white space at *buf, and updates *buf to point to the
 * first found non-space character (if any). Returns the length of
A
Alex Elder 已提交
5048 5049
 * the token (string of non-white space characters) found.  Note
 * that *buf must be terminated with '\0'.
5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063
 */
static inline size_t next_token(const char **buf)
{
        /*
        * These are the characters that produce nonzero for
        * isspace() in the "C" and "POSIX" locales.
        */
        const char *spaces = " \f\n\r\t\v";

        *buf += strspn(*buf, spaces);	/* Find start of token */

	return strcspn(*buf, spaces);   /* Return token length */
}

A
Alex Elder 已提交
5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085
/*
 * Finds the next token in *buf, dynamically allocates a buffer big
 * enough to hold a copy of it, and copies the token into the new
 * buffer.  The copy is guaranteed to be terminated with '\0'.  Note
 * that a duplicate buffer is created even for a zero-length token.
 *
 * Returns a pointer to the newly-allocated duplicate, or a null
 * pointer if memory for the duplicate was not available.  If
 * the lenp argument is a non-null pointer, the length of the token
 * (not including the '\0') is returned in *lenp.
 *
 * If successful, the *buf pointer will be updated to point beyond
 * the end of the found token.
 *
 * Note: uses GFP_KERNEL for allocation.
 */
static inline char *dup_token(const char **buf, size_t *lenp)
{
	char *dup;
	size_t len;

	len = next_token(buf);
A
Alex Elder 已提交
5086
	dup = kmemdup(*buf, len + 1, GFP_KERNEL);
A
Alex Elder 已提交
5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097
	if (!dup)
		return NULL;
	*(dup + len) = '\0';
	*buf += len;

	if (lenp)
		*lenp = len;

	return dup;
}

5098
/*
5099 5100 5101 5102
 * Parse the options provided for an "rbd add" (i.e., rbd image
 * mapping) request.  These arrive via a write to /sys/bus/rbd/add,
 * and the data written is passed here via a NUL-terminated buffer.
 * Returns 0 if successful or an error code otherwise.
A
Alex Elder 已提交
5103
 *
5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137
 * The information extracted from these options is recorded in
 * the other parameters which return dynamically-allocated
 * structures:
 *  ceph_opts
 *      The address of a pointer that will refer to a ceph options
 *      structure.  Caller must release the returned pointer using
 *      ceph_destroy_options() when it is no longer needed.
 *  rbd_opts
 *	Address of an rbd options pointer.  Fully initialized by
 *	this function; caller must release with kfree().
 *  spec
 *	Address of an rbd image specification pointer.  Fully
 *	initialized by this function based on parsed options.
 *	Caller must release with rbd_spec_put().
 *
 * The options passed take this form:
 *  <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
 * where:
 *  <mon_addrs>
 *      A comma-separated list of one or more monitor addresses.
 *      A monitor address is an ip address, optionally followed
 *      by a port number (separated by a colon).
 *        I.e.:  ip1[:port1][,ip2[:port2]...]
 *  <options>
 *      A comma-separated list of ceph and/or rbd options.
 *  <pool_name>
 *      The name of the rados pool containing the rbd image.
 *  <image_name>
 *      The name of the image in that pool to map.
 *  <snap_id>
 *      An optional snapshot id.  If provided, the mapping will
 *      present data from the image at the time that snapshot was
 *      created.  The image head is used if no snapshot id is
 *      provided.  Snapshot mappings are always read-only.
5138
 */
5139
static int rbd_add_parse_args(const char *buf,
5140
				struct ceph_options **ceph_opts,
5141 5142
				struct rbd_options **opts,
				struct rbd_spec **rbd_spec)
5143
{
A
Alex Elder 已提交
5144
	size_t len;
5145
	char *options;
5146
	const char *mon_addrs;
5147
	char *snap_name;
5148
	size_t mon_addrs_size;
5149
	struct rbd_spec *spec = NULL;
5150
	struct rbd_options *rbd_opts = NULL;
5151
	struct ceph_options *copts;
5152
	int ret;
5153 5154 5155

	/* The first four tokens are required */

5156
	len = next_token(&buf);
5157 5158 5159 5160
	if (!len) {
		rbd_warn(NULL, "no monitor address(es) provided");
		return -EINVAL;
	}
5161
	mon_addrs = buf;
5162
	mon_addrs_size = len + 1;
5163
	buf += len;
5164

5165
	ret = -EINVAL;
5166 5167
	options = dup_token(&buf, NULL);
	if (!options)
5168
		return -ENOMEM;
5169 5170 5171 5172
	if (!*options) {
		rbd_warn(NULL, "no options provided");
		goto out_err;
	}
5173

5174 5175
	spec = rbd_spec_alloc();
	if (!spec)
5176
		goto out_mem;
5177 5178 5179 5180

	spec->pool_name = dup_token(&buf, NULL);
	if (!spec->pool_name)
		goto out_mem;
5181 5182 5183 5184
	if (!*spec->pool_name) {
		rbd_warn(NULL, "no pool name provided");
		goto out_err;
	}
5185

A
Alex Elder 已提交
5186
	spec->image_name = dup_token(&buf, NULL);
5187
	if (!spec->image_name)
5188
		goto out_mem;
5189 5190 5191 5192
	if (!*spec->image_name) {
		rbd_warn(NULL, "no image name provided");
		goto out_err;
	}
5193

5194 5195 5196 5197
	/*
	 * Snapshot name is optional; default is to use "-"
	 * (indicating the head/no snapshot).
	 */
5198
	len = next_token(&buf);
5199
	if (!len) {
5200 5201
		buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
		len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
5202
	} else if (len > RBD_MAX_SNAP_NAME_LEN) {
5203
		ret = -ENAMETOOLONG;
5204
		goto out_err;
5205
	}
5206 5207
	snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
	if (!snap_name)
5208
		goto out_mem;
5209 5210
	*(snap_name + len) = '\0';
	spec->snap_name = snap_name;
A
Alex Elder 已提交
5211

5212
	/* Initialize all rbd options to the defaults */
5213

5214 5215 5216 5217 5218
	rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
	if (!rbd_opts)
		goto out_mem;

	rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
I
Ilya Dryomov 已提交
5219
	rbd_opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
5220
	rbd_opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT;
I
Ilya Dryomov 已提交
5221
	rbd_opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT;
I
Ilya Dryomov 已提交
5222
	rbd_opts->exclusive = RBD_EXCLUSIVE_DEFAULT;
I
Ilya Dryomov 已提交
5223
	rbd_opts->trim = RBD_TRIM_DEFAULT;
A
Alex Elder 已提交
5224

5225
	copts = ceph_parse_options(options, mon_addrs,
5226
					mon_addrs + mon_addrs_size - 1,
5227
					parse_rbd_opts_token, rbd_opts);
5228 5229
	if (IS_ERR(copts)) {
		ret = PTR_ERR(copts);
5230 5231
		goto out_err;
	}
5232 5233 5234
	kfree(options);

	*ceph_opts = copts;
5235
	*opts = rbd_opts;
5236
	*rbd_spec = spec;
5237

5238
	return 0;
5239
out_mem:
5240
	ret = -ENOMEM;
A
Alex Elder 已提交
5241
out_err:
5242 5243
	kfree(rbd_opts);
	rbd_spec_put(spec);
5244
	kfree(options);
A
Alex Elder 已提交
5245

5246
	return ret;
5247 5248
}

I
Ilya Dryomov 已提交
5249 5250 5251 5252 5253 5254 5255 5256 5257 5258
static void rbd_dev_image_unlock(struct rbd_device *rbd_dev)
{
	down_write(&rbd_dev->lock_rwsem);
	if (__rbd_is_lock_owner(rbd_dev))
		rbd_unlock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);
}

static int rbd_add_acquire_lock(struct rbd_device *rbd_dev)
{
5259 5260
	int ret;

I
Ilya Dryomov 已提交
5261 5262 5263 5264 5265 5266 5267
	if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) {
		rbd_warn(rbd_dev, "exclusive-lock feature is not enabled");
		return -EINVAL;
	}

	/* FIXME: "rbd map --exclusive" should be in interruptible */
	down_read(&rbd_dev->lock_rwsem);
5268
	ret = rbd_wait_state_locked(rbd_dev, true);
I
Ilya Dryomov 已提交
5269
	up_read(&rbd_dev->lock_rwsem);
5270
	if (ret) {
I
Ilya Dryomov 已提交
5271 5272 5273 5274 5275 5276 5277
		rbd_warn(rbd_dev, "failed to acquire exclusive lock");
		return -EROFS;
	}

	return 0;
}

A
Alex Elder 已提交
5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295
/*
 * An rbd format 2 image has a unique identifier, distinct from the
 * name given to it by the user.  Internally, that identifier is
 * what's used to specify the names of objects related to the image.
 *
 * A special "rbd id" object is used to map an rbd image name to its
 * id.  If that object doesn't exist, then there is no v2 rbd image
 * with the supplied name.
 *
 * This function will record the given rbd_dev's image_id field if
 * it can be determined, and in that case will return 0.  If any
 * errors occur a negative errno will be returned and the rbd_dev's
 * image_id field will be unchanged (and should be NULL).
 */
static int rbd_dev_image_id(struct rbd_device *rbd_dev)
{
	int ret;
	size_t size;
5296
	CEPH_DEFINE_OID_ONSTACK(oid);
A
Alex Elder 已提交
5297
	void *response;
5298
	char *image_id;
5299

A
Alex Elder 已提交
5300 5301 5302
	/*
	 * When probing a parent image, the image id is already
	 * known (and the image name likely is not).  There's no
5303 5304
	 * need to fetch the image id again in this case.  We
	 * do still need to set the image format though.
A
Alex Elder 已提交
5305
	 */
5306 5307 5308
	if (rbd_dev->spec->image_id) {
		rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;

A
Alex Elder 已提交
5309
		return 0;
5310
	}
A
Alex Elder 已提交
5311

A
Alex Elder 已提交
5312 5313 5314 5315
	/*
	 * First, see if the format 2 image id file exists, and if
	 * so, get the image's persistent id from it.
	 */
5316 5317 5318 5319 5320 5321
	ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX,
			       rbd_dev->spec->image_name);
	if (ret)
		return ret;

	dout("rbd id object name is %s\n", oid.name);
A
Alex Elder 已提交
5322 5323 5324 5325 5326 5327 5328 5329 5330 5331

	/* Response will be an encoded string, which includes a length */

	size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
	response = kzalloc(size, GFP_NOIO);
	if (!response) {
		ret = -ENOMEM;
		goto out;
	}

5332 5333
	/* If it doesn't exist we'll assume it's a format 1 image */

5334 5335 5336
	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
				  "get_id", NULL, 0,
				  response, RBD_IMAGE_ID_LEN_MAX);
5337
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5338 5339 5340 5341 5342
	if (ret == -ENOENT) {
		image_id = kstrdup("", GFP_KERNEL);
		ret = image_id ? 0 : -ENOMEM;
		if (!ret)
			rbd_dev->image_format = 1;
5343
	} else if (ret >= 0) {
5344 5345 5346
		void *p = response;

		image_id = ceph_extract_encoded_string(&p, p + ret,
A
Alex Elder 已提交
5347
						NULL, GFP_NOIO);
5348
		ret = PTR_ERR_OR_ZERO(image_id);
5349 5350 5351 5352 5353 5354 5355
		if (!ret)
			rbd_dev->image_format = 2;
	}

	if (!ret) {
		rbd_dev->spec->image_id = image_id;
		dout("image_id is %s\n", image_id);
A
Alex Elder 已提交
5356 5357 5358
	}
out:
	kfree(response);
5359
	ceph_oid_destroy(&oid);
A
Alex Elder 已提交
5360 5361 5362
	return ret;
}

A
Alex Elder 已提交
5363 5364 5365 5366
/*
 * Undo whatever state changes are made by v1 or v2 header info
 * call.
 */
A
Alex Elder 已提交
5367 5368 5369 5370
static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
{
	struct rbd_image_header	*header;

5371
	rbd_dev_parent_put(rbd_dev);
A
Alex Elder 已提交
5372 5373 5374 5375

	/* Free dynamic fields from the header, then zero it out */

	header = &rbd_dev->header;
5376
	ceph_put_snap_context(header->snapc);
A
Alex Elder 已提交
5377 5378 5379 5380 5381 5382
	kfree(header->snap_sizes);
	kfree(header->snap_names);
	kfree(header->object_prefix);
	memset(header, 0, sizeof (*header));
}

5383
static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
5384 5385 5386
{
	int ret;

5387
	ret = rbd_dev_v2_object_prefix(rbd_dev);
5388
	if (ret)
5389 5390
		goto out_err;

5391 5392 5393 5394
	/*
	 * Get the and check features for the image.  Currently the
	 * features are assumed to never change.
	 */
5395
	ret = rbd_dev_v2_features(rbd_dev);
5396
	if (ret)
5397
		goto out_err;
5398

5399 5400 5401 5402 5403 5404 5405
	/* If the image supports fancy striping, get its parameters */

	if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
		ret = rbd_dev_v2_striping_info(rbd_dev);
		if (ret < 0)
			goto out_err;
	}
5406

5407 5408 5409 5410 5411 5412
	if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) {
		ret = rbd_dev_v2_data_pool(rbd_dev);
		if (ret)
			goto out_err;
	}

I
Ilya Dryomov 已提交
5413
	rbd_init_layout(rbd_dev);
A
Alex Elder 已提交
5414
	return 0;
I
Ilya Dryomov 已提交
5415

5416
out_err:
A
Alex Elder 已提交
5417
	rbd_dev->header.features = 0;
5418 5419
	kfree(rbd_dev->header.object_prefix);
	rbd_dev->header.object_prefix = NULL;
5420
	return ret;
5421 5422
}

5423 5424 5425 5426 5427 5428
/*
 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() ->
 * rbd_dev_image_probe() recursion depth, which means it's also the
 * length of the already discovered part of the parent chain.
 */
static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth)
A
Alex Elder 已提交
5429
{
5430
	struct rbd_device *parent = NULL;
5431 5432 5433 5434 5435
	int ret;

	if (!rbd_dev->parent_spec)
		return 0;

5436 5437 5438 5439 5440 5441
	if (++depth > RBD_MAX_PARENT_CHAIN_LEN) {
		pr_info("parent chain is too long (%d)\n", depth);
		ret = -EINVAL;
		goto out_err;
	}

5442
	parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec);
5443 5444
	if (!parent) {
		ret = -ENOMEM;
5445
		goto out_err;
5446 5447 5448 5449 5450 5451 5452 5453
	}

	/*
	 * Images related by parent/child relationships always share
	 * rbd_client and spec/parent_spec, so bump their refcounts.
	 */
	__rbd_get_client(rbd_dev->rbd_client);
	rbd_spec_get(rbd_dev->parent_spec);
5454

5455
	ret = rbd_dev_image_probe(parent, depth);
5456 5457
	if (ret < 0)
		goto out_err;
5458

5459
	rbd_dev->parent = parent;
5460
	atomic_set(&rbd_dev->parent_ref, 1);
5461
	return 0;
5462

5463
out_err:
5464
	rbd_dev_unparent(rbd_dev);
5465
	rbd_dev_destroy(parent);
5466 5467 5468
	return ret;
}

5469 5470 5471 5472 5473 5474 5475 5476 5477
static void rbd_dev_device_release(struct rbd_device *rbd_dev)
{
	clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
	rbd_dev_mapping_clear(rbd_dev);
	rbd_free_disk(rbd_dev);
	if (!single_major)
		unregister_blkdev(rbd_dev->major, rbd_dev->name);
}

I
Ilya Dryomov 已提交
5478 5479 5480 5481
/*
 * rbd_dev->header_rwsem must be locked for write and will be unlocked
 * upon return.
 */
5482
static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
5483
{
A
Alex Elder 已提交
5484
	int ret;
A
Alex Elder 已提交
5485

5486
	/* Record our major and minor device numbers. */
A
Alex Elder 已提交
5487

5488 5489 5490
	if (!single_major) {
		ret = register_blkdev(0, rbd_dev->name);
		if (ret < 0)
5491
			goto err_out_unlock;
5492 5493 5494 5495 5496 5497 5498

		rbd_dev->major = ret;
		rbd_dev->minor = 0;
	} else {
		rbd_dev->major = rbd_major;
		rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
	}
A
Alex Elder 已提交
5499 5500 5501 5502 5503 5504 5505

	/* Set up the blkdev mapping. */

	ret = rbd_init_disk(rbd_dev);
	if (ret)
		goto err_out_blkdev;

5506
	ret = rbd_dev_mapping_set(rbd_dev);
A
Alex Elder 已提交
5507 5508
	if (ret)
		goto err_out_disk;
I
Ilya Dryomov 已提交
5509

5510
	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
5511
	set_disk_ro(rbd_dev->disk, rbd_dev->opts->read_only);
5512

5513
	ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id);
5514
	if (ret)
5515
		goto err_out_mapping;
A
Alex Elder 已提交
5516

5517
	set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
I
Ilya Dryomov 已提交
5518
	up_write(&rbd_dev->header_rwsem);
5519
	return 0;
5520

5521 5522
err_out_mapping:
	rbd_dev_mapping_clear(rbd_dev);
A
Alex Elder 已提交
5523 5524 5525
err_out_disk:
	rbd_free_disk(rbd_dev);
err_out_blkdev:
5526 5527
	if (!single_major)
		unregister_blkdev(rbd_dev->major, rbd_dev->name);
I
Ilya Dryomov 已提交
5528 5529
err_out_unlock:
	up_write(&rbd_dev->header_rwsem);
A
Alex Elder 已提交
5530 5531 5532
	return ret;
}

A
Alex Elder 已提交
5533 5534 5535
static int rbd_dev_header_name(struct rbd_device *rbd_dev)
{
	struct rbd_spec *spec = rbd_dev->spec;
5536
	int ret;
A
Alex Elder 已提交
5537 5538 5539 5540 5541

	/* Record the header object name for this rbd image. */

	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (rbd_dev->image_format == 1)
5542 5543
		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
				       spec->image_name, RBD_SUFFIX);
A
Alex Elder 已提交
5544
	else
5545 5546
		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
				       RBD_HEADER_PREFIX, spec->image_id);
A
Alex Elder 已提交
5547

5548
	return ret;
A
Alex Elder 已提交
5549 5550
}

5551 5552
static void rbd_dev_image_release(struct rbd_device *rbd_dev)
{
A
Alex Elder 已提交
5553
	rbd_dev_unprobe(rbd_dev);
5554 5555
	if (rbd_dev->opts)
		rbd_unregister_watch(rbd_dev);
A
Alex Elder 已提交
5556 5557 5558
	rbd_dev->image_format = 0;
	kfree(rbd_dev->spec->image_id);
	rbd_dev->spec->image_id = NULL;
5559 5560
}

5561 5562
/*
 * Probe for the existence of the header object for the given rbd
5563 5564 5565
 * device.  If this image is the one being mapped (i.e., not a
 * parent), initiate a watch on its header object before using that
 * object to get detailed information about the rbd image.
5566
 */
5567
static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
5568 5569 5570 5571
{
	int ret;

	/*
A
Alex Elder 已提交
5572 5573 5574 5575
	 * Get the id from the image id object.  Unless there's an
	 * error, rbd_dev->spec->image_id will be filled in with
	 * a dynamically-allocated string, and rbd_dev->image_format
	 * will be set to either 1 or 2.
5576 5577 5578
	 */
	ret = rbd_dev_image_id(rbd_dev);
	if (ret)
5579 5580
		return ret;

A
Alex Elder 已提交
5581 5582 5583 5584
	ret = rbd_dev_header_name(rbd_dev);
	if (ret)
		goto err_out_format;

5585
	if (!depth) {
5586
		ret = rbd_register_watch(rbd_dev);
5587 5588 5589 5590 5591
		if (ret) {
			if (ret == -ENOENT)
				pr_info("image %s/%s does not exist\n",
					rbd_dev->spec->pool_name,
					rbd_dev->spec->image_name);
5592
			goto err_out_format;
5593
		}
5594
	}
5595

5596
	ret = rbd_dev_header_info(rbd_dev);
5597
	if (ret)
5598
		goto err_out_watch;
A
Alex Elder 已提交
5599

5600 5601 5602 5603 5604 5605
	/*
	 * If this image is the one being mapped, we have pool name and
	 * id, image name and id, and snap name - need to fill snap id.
	 * Otherwise this is a parent image, identified by pool, image
	 * and snap ids - need to fill in names for those ids.
	 */
5606
	if (!depth)
5607 5608 5609
		ret = rbd_spec_fill_snap_id(rbd_dev);
	else
		ret = rbd_spec_fill_names(rbd_dev);
5610 5611 5612 5613 5614 5615
	if (ret) {
		if (ret == -ENOENT)
			pr_info("snap %s/%s@%s does not exist\n",
				rbd_dev->spec->pool_name,
				rbd_dev->spec->image_name,
				rbd_dev->spec->snap_name);
A
Alex Elder 已提交
5616
		goto err_out_probe;
5617
	}
5618

5619 5620 5621 5622 5623 5624 5625 5626 5627
	if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
		ret = rbd_dev_v2_parent_info(rbd_dev);
		if (ret)
			goto err_out_probe;

		/*
		 * Need to warn users if this image is the one being
		 * mapped and has a parent.
		 */
5628
		if (!depth && rbd_dev->parent_spec)
5629 5630 5631 5632
			rbd_warn(rbd_dev,
				 "WARNING: kernel layering is EXPERIMENTAL!");
	}

5633
	ret = rbd_dev_probe_parent(rbd_dev, depth);
A
Alex Elder 已提交
5634 5635 5636 5637
	if (ret)
		goto err_out_probe;

	dout("discovered format %u image, header name is %s\n",
5638
		rbd_dev->image_format, rbd_dev->header_oid.name);
A
Alex Elder 已提交
5639
	return 0;
5640

A
Alex Elder 已提交
5641 5642
err_out_probe:
	rbd_dev_unprobe(rbd_dev);
5643
err_out_watch:
5644
	if (!depth)
5645
		rbd_unregister_watch(rbd_dev);
A
Alex Elder 已提交
5646 5647
err_out_format:
	rbd_dev->image_format = 0;
5648 5649
	kfree(rbd_dev->spec->image_id);
	rbd_dev->spec->image_id = NULL;
5650 5651 5652
	return ret;
}

5653 5654 5655
static ssize_t do_rbd_add(struct bus_type *bus,
			  const char *buf,
			  size_t count)
5656
{
5657
	struct rbd_device *rbd_dev = NULL;
5658
	struct ceph_options *ceph_opts = NULL;
5659
	struct rbd_options *rbd_opts = NULL;
5660
	struct rbd_spec *spec = NULL;
5661
	struct rbd_client *rbdc;
5662
	int rc;
5663 5664 5665 5666 5667

	if (!try_module_get(THIS_MODULE))
		return -ENODEV;

	/* parse add command */
5668
	rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
5669
	if (rc < 0)
5670
		goto out;
5671

5672 5673 5674
	rbdc = rbd_get_client(ceph_opts);
	if (IS_ERR(rbdc)) {
		rc = PTR_ERR(rbdc);
5675
		goto err_out_args;
5676
	}
5677 5678

	/* pick the pool */
5679
	rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name);
5680 5681 5682
	if (rc < 0) {
		if (rc == -ENOENT)
			pr_info("pool %s does not exist\n", spec->pool_name);
5683
		goto err_out_client;
5684
	}
A
Alex Elder 已提交
5685
	spec->pool_id = (u64)rc;
5686

5687
	rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
5688 5689
	if (!rbd_dev) {
		rc = -ENOMEM;
5690
		goto err_out_client;
5691
	}
5692 5693
	rbdc = NULL;		/* rbd_dev now owns this */
	spec = NULL;		/* rbd_dev now owns this */
5694
	rbd_opts = NULL;	/* rbd_dev now owns this */
5695

5696 5697 5698 5699 5700 5701
	rbd_dev->config_info = kstrdup(buf, GFP_KERNEL);
	if (!rbd_dev->config_info) {
		rc = -ENOMEM;
		goto err_out_rbd_dev;
	}

I
Ilya Dryomov 已提交
5702
	down_write(&rbd_dev->header_rwsem);
5703
	rc = rbd_dev_image_probe(rbd_dev, 0);
5704 5705
	if (rc < 0) {
		up_write(&rbd_dev->header_rwsem);
5706
		goto err_out_rbd_dev;
5707
	}
5708

5709 5710
	/* If we are mapping a snapshot it must be marked read-only */
	if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5711
		rbd_dev->opts->read_only = true;
5712

5713
	rc = rbd_dev_device_setup(rbd_dev);
5714
	if (rc)
5715
		goto err_out_image_probe;
A
Alex Elder 已提交
5716

I
Ilya Dryomov 已提交
5717 5718 5719 5720
	if (rbd_dev->opts->exclusive) {
		rc = rbd_add_acquire_lock(rbd_dev);
		if (rc)
			goto err_out_device_setup;
A
Alex Elder 已提交
5721 5722
	}

5723 5724 5725 5726
	/* Everything's ready.  Announce the disk to the world. */

	rc = device_add(&rbd_dev->dev);
	if (rc)
I
Ilya Dryomov 已提交
5727
		goto err_out_image_lock;
5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739

	add_disk(rbd_dev->disk);
	/* see rbd_init_disk() */
	blk_put_queue(rbd_dev->disk->queue);

	spin_lock(&rbd_dev_list_lock);
	list_add_tail(&rbd_dev->node, &rbd_dev_list);
	spin_unlock(&rbd_dev_list_lock);

	pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name,
		(unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT,
		rbd_dev->header.features);
5740 5741 5742 5743
	rc = count;
out:
	module_put(THIS_MODULE);
	return rc;
5744

I
Ilya Dryomov 已提交
5745 5746
err_out_image_lock:
	rbd_dev_image_unlock(rbd_dev);
5747 5748
err_out_device_setup:
	rbd_dev_device_release(rbd_dev);
5749 5750
err_out_image_probe:
	rbd_dev_image_release(rbd_dev);
5751 5752
err_out_rbd_dev:
	rbd_dev_destroy(rbd_dev);
5753
err_out_client:
5754
	rbd_put_client(rbdc);
5755
err_out_args:
5756
	rbd_spec_put(spec);
5757
	kfree(rbd_opts);
5758
	goto out;
5759 5760
}

5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777
static ssize_t rbd_add(struct bus_type *bus,
		       const char *buf,
		       size_t count)
{
	if (single_major)
		return -EINVAL;

	return do_rbd_add(bus, buf, count);
}

static ssize_t rbd_add_single_major(struct bus_type *bus,
				    const char *buf,
				    size_t count)
{
	return do_rbd_add(bus, buf, count);
}

5778 5779
static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
{
A
Alex Elder 已提交
5780
	while (rbd_dev->parent) {
5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792
		struct rbd_device *first = rbd_dev;
		struct rbd_device *second = first->parent;
		struct rbd_device *third;

		/*
		 * Follow to the parent with no grandparent and
		 * remove it.
		 */
		while (second && (third = second->parent)) {
			first = second;
			second = third;
		}
A
Alex Elder 已提交
5793
		rbd_assert(second);
5794
		rbd_dev_image_release(second);
5795
		rbd_dev_destroy(second);
A
Alex Elder 已提交
5796 5797 5798 5799
		first->parent = NULL;
		first->parent_overlap = 0;

		rbd_assert(first->parent_spec);
5800 5801 5802 5803 5804
		rbd_spec_put(first->parent_spec);
		first->parent_spec = NULL;
	}
}

5805 5806 5807
static ssize_t do_rbd_remove(struct bus_type *bus,
			     const char *buf,
			     size_t count)
5808 5809
{
	struct rbd_device *rbd_dev = NULL;
5810 5811
	struct list_head *tmp;
	int dev_id;
M
Mike Christie 已提交
5812
	char opt_buf[6];
5813
	bool already = false;
M
Mike Christie 已提交
5814
	bool force = false;
5815
	int ret;
5816

M
Mike Christie 已提交
5817 5818 5819 5820 5821
	dev_id = -1;
	opt_buf[0] = '\0';
	sscanf(buf, "%d %5s", &dev_id, opt_buf);
	if (dev_id < 0) {
		pr_err("dev_id out of range\n");
5822
		return -EINVAL;
M
Mike Christie 已提交
5823 5824 5825 5826 5827 5828 5829 5830 5831
	}
	if (opt_buf[0] != '\0') {
		if (!strcmp(opt_buf, "force")) {
			force = true;
		} else {
			pr_err("bad remove option at '%s'\n", opt_buf);
			return -EINVAL;
		}
	}
5832

5833 5834 5835 5836 5837 5838 5839 5840
	ret = -ENOENT;
	spin_lock(&rbd_dev_list_lock);
	list_for_each(tmp, &rbd_dev_list) {
		rbd_dev = list_entry(tmp, struct rbd_device, node);
		if (rbd_dev->dev_id == dev_id) {
			ret = 0;
			break;
		}
5841
	}
5842 5843
	if (!ret) {
		spin_lock_irq(&rbd_dev->lock);
M
Mike Christie 已提交
5844
		if (rbd_dev->open_count && !force)
5845 5846
			ret = -EBUSY;
		else
5847 5848
			already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
							&rbd_dev->flags);
5849 5850 5851
		spin_unlock_irq(&rbd_dev->lock);
	}
	spin_unlock(&rbd_dev_list_lock);
5852
	if (ret < 0 || already)
5853
		return ret;
5854

M
Mike Christie 已提交
5855 5856 5857 5858 5859 5860 5861 5862 5863
	if (force) {
		/*
		 * Prevent new IO from being queued and wait for existing
		 * IO to complete/fail.
		 */
		blk_mq_freeze_queue(rbd_dev->disk->queue);
		blk_set_queue_dying(rbd_dev->disk->queue);
	}

5864 5865 5866 5867 5868
	del_gendisk(rbd_dev->disk);
	spin_lock(&rbd_dev_list_lock);
	list_del_init(&rbd_dev->node);
	spin_unlock(&rbd_dev_list_lock);
	device_del(&rbd_dev->dev);
5869

I
Ilya Dryomov 已提交
5870
	rbd_dev_image_unlock(rbd_dev);
5871
	rbd_dev_device_release(rbd_dev);
5872
	rbd_dev_image_release(rbd_dev);
5873
	rbd_dev_destroy(rbd_dev);
5874
	return count;
5875 5876
}

5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892 5893
static ssize_t rbd_remove(struct bus_type *bus,
			  const char *buf,
			  size_t count)
{
	if (single_major)
		return -EINVAL;

	return do_rbd_remove(bus, buf, count);
}

static ssize_t rbd_remove_single_major(struct bus_type *bus,
				       const char *buf,
				       size_t count)
{
	return do_rbd_remove(bus, buf, count);
}

5894 5895
/*
 * create control files in sysfs
5896
 * /sys/bus/rbd/...
5897 5898 5899
 */
static int rbd_sysfs_init(void)
{
5900
	int ret;
5901

5902
	ret = device_register(&rbd_root_dev);
A
Alex Elder 已提交
5903
	if (ret < 0)
5904
		return ret;
5905

5906 5907 5908
	ret = bus_register(&rbd_bus_type);
	if (ret < 0)
		device_unregister(&rbd_root_dev);
5909 5910 5911 5912 5913 5914

	return ret;
}

static void rbd_sysfs_cleanup(void)
{
5915
	bus_unregister(&rbd_bus_type);
5916
	device_unregister(&rbd_root_dev);
5917 5918
}

5919 5920 5921
static int rbd_slab_init(void)
{
	rbd_assert(!rbd_img_request_cache);
G
Geliang Tang 已提交
5922
	rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0);
5923 5924 5925 5926
	if (!rbd_img_request_cache)
		return -ENOMEM;

	rbd_assert(!rbd_obj_request_cache);
G
Geliang Tang 已提交
5927
	rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0);
5928 5929 5930
	if (!rbd_obj_request_cache)
		goto out_err;

5931
	return 0;
5932

5933
out_err:
5934 5935
	kmem_cache_destroy(rbd_img_request_cache);
	rbd_img_request_cache = NULL;
5936 5937 5938 5939 5940
	return -ENOMEM;
}

static void rbd_slab_exit(void)
{
5941 5942 5943 5944
	rbd_assert(rbd_obj_request_cache);
	kmem_cache_destroy(rbd_obj_request_cache);
	rbd_obj_request_cache = NULL;

5945 5946 5947 5948 5949
	rbd_assert(rbd_img_request_cache);
	kmem_cache_destroy(rbd_img_request_cache);
	rbd_img_request_cache = NULL;
}

A
Alex Elder 已提交
5950
static int __init rbd_init(void)
5951 5952 5953
{
	int rc;

5954 5955 5956 5957
	if (!libceph_compatible(NULL)) {
		rbd_warn(NULL, "libceph incompatibility (quitting)");
		return -EINVAL;
	}
I
Ilya Dryomov 已提交
5958

5959
	rc = rbd_slab_init();
5960 5961
	if (rc)
		return rc;
I
Ilya Dryomov 已提交
5962

5963 5964
	/*
	 * The number of active work items is limited by the number of
I
Ilya Dryomov 已提交
5965
	 * rbd devices * queue depth, so leave @max_active at default.
5966 5967 5968 5969 5970 5971 5972
	 */
	rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
	if (!rbd_wq) {
		rc = -ENOMEM;
		goto err_out_slab;
	}

5973 5974 5975 5976
	if (single_major) {
		rbd_major = register_blkdev(0, RBD_DRV_NAME);
		if (rbd_major < 0) {
			rc = rbd_major;
5977
			goto err_out_wq;
5978 5979 5980
		}
	}

5981 5982
	rc = rbd_sysfs_init();
	if (rc)
5983 5984 5985 5986 5987 5988
		goto err_out_blkdev;

	if (single_major)
		pr_info("loaded (major %d)\n", rbd_major);
	else
		pr_info("loaded\n");
5989

I
Ilya Dryomov 已提交
5990 5991
	return 0;

5992 5993 5994
err_out_blkdev:
	if (single_major)
		unregister_blkdev(rbd_major, RBD_DRV_NAME);
5995 5996
err_out_wq:
	destroy_workqueue(rbd_wq);
I
Ilya Dryomov 已提交
5997 5998
err_out_slab:
	rbd_slab_exit();
5999
	return rc;
6000 6001
}

A
Alex Elder 已提交
6002
static void __exit rbd_exit(void)
6003
{
I
Ilya Dryomov 已提交
6004
	ida_destroy(&rbd_dev_id_ida);
6005
	rbd_sysfs_cleanup();
6006 6007
	if (single_major)
		unregister_blkdev(rbd_major, RBD_DRV_NAME);
6008
	destroy_workqueue(rbd_wq);
6009
	rbd_slab_exit();
6010 6011 6012 6013 6014
}

module_init(rbd_init);
module_exit(rbd_exit);

A
Alex Elder 已提交
6015
MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
6016 6017 6018 6019 6020
MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
/* following authorship retained from original osdblk.c */
MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");

6021
MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
6022
MODULE_LICENSE("GPL");