caps.c 84.9 KB
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#include <linux/ceph/ceph_debug.h>
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#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
#include <linux/wait.h>
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#include <linux/writeback.h>
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#include "super.h"
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#include "mds_client.h"
#include <linux/ceph/decode.h>
#include <linux/ceph/messenger.h>
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/*
 * Capability management
 *
 * The Ceph metadata servers control client access to inode metadata
 * and file data by issuing capabilities, granting clients permission
 * to read and/or write both inode field and file data to OSDs
 * (storage nodes).  Each capability consists of a set of bits
 * indicating which operations are allowed.
 *
 * If the client holds a *_SHARED cap, the client has a coherent value
 * that can be safely read from the cached inode.
 *
 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
 * client is allowed to change inode attributes (e.g., file size,
 * mtime), note its dirty state in the ceph_cap, and asynchronously
 * flush that metadata change to the MDS.
 *
 * In the event of a conflicting operation (perhaps by another
 * client), the MDS will revoke the conflicting client capabilities.
 *
 * In order for a client to cache an inode, it must hold a capability
 * with at least one MDS server.  When inodes are released, release
 * notifications are batched and periodically sent en masse to the MDS
 * cluster to release server state.
 */


/*
 * Generate readable cap strings for debugging output.
 */
#define MAX_CAP_STR 20
static char cap_str[MAX_CAP_STR][40];
static DEFINE_SPINLOCK(cap_str_lock);
static int last_cap_str;

static char *gcap_string(char *s, int c)
{
	if (c & CEPH_CAP_GSHARED)
		*s++ = 's';
	if (c & CEPH_CAP_GEXCL)
		*s++ = 'x';
	if (c & CEPH_CAP_GCACHE)
		*s++ = 'c';
	if (c & CEPH_CAP_GRD)
		*s++ = 'r';
	if (c & CEPH_CAP_GWR)
		*s++ = 'w';
	if (c & CEPH_CAP_GBUFFER)
		*s++ = 'b';
	if (c & CEPH_CAP_GLAZYIO)
		*s++ = 'l';
	return s;
}

const char *ceph_cap_string(int caps)
{
	int i;
	char *s;
	int c;

	spin_lock(&cap_str_lock);
	i = last_cap_str++;
	if (last_cap_str == MAX_CAP_STR)
		last_cap_str = 0;
	spin_unlock(&cap_str_lock);

	s = cap_str[i];

	if (caps & CEPH_CAP_PIN)
		*s++ = 'p';

	c = (caps >> CEPH_CAP_SAUTH) & 3;
	if (c) {
		*s++ = 'A';
		s = gcap_string(s, c);
	}

	c = (caps >> CEPH_CAP_SLINK) & 3;
	if (c) {
		*s++ = 'L';
		s = gcap_string(s, c);
	}

	c = (caps >> CEPH_CAP_SXATTR) & 3;
	if (c) {
		*s++ = 'X';
		s = gcap_string(s, c);
	}

	c = caps >> CEPH_CAP_SFILE;
	if (c) {
		*s++ = 'F';
		s = gcap_string(s, c);
	}

	if (s == cap_str[i])
		*s++ = '-';
	*s = 0;
	return cap_str[i];
}

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void ceph_caps_init(struct ceph_mds_client *mdsc)
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{
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	INIT_LIST_HEAD(&mdsc->caps_list);
	spin_lock_init(&mdsc->caps_list_lock);
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}

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void ceph_caps_finalize(struct ceph_mds_client *mdsc)
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{
	struct ceph_cap *cap;

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	spin_lock(&mdsc->caps_list_lock);
	while (!list_empty(&mdsc->caps_list)) {
		cap = list_first_entry(&mdsc->caps_list,
				       struct ceph_cap, caps_item);
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		list_del(&cap->caps_item);
		kmem_cache_free(ceph_cap_cachep, cap);
	}
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	mdsc->caps_total_count = 0;
	mdsc->caps_avail_count = 0;
	mdsc->caps_use_count = 0;
	mdsc->caps_reserve_count = 0;
	mdsc->caps_min_count = 0;
	spin_unlock(&mdsc->caps_list_lock);
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}

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void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
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{
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	spin_lock(&mdsc->caps_list_lock);
	mdsc->caps_min_count += delta;
	BUG_ON(mdsc->caps_min_count < 0);
	spin_unlock(&mdsc->caps_list_lock);
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}

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int ceph_reserve_caps(struct ceph_mds_client *mdsc,
		      struct ceph_cap_reservation *ctx, int need)
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{
	int i;
	struct ceph_cap *cap;
	int have;
	int alloc = 0;
	LIST_HEAD(newcaps);
	int ret = 0;

	dout("reserve caps ctx=%p need=%d\n", ctx, need);

	/* first reserve any caps that are already allocated */
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	spin_lock(&mdsc->caps_list_lock);
	if (mdsc->caps_avail_count >= need)
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		have = need;
	else
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		have = mdsc->caps_avail_count;
	mdsc->caps_avail_count -= have;
	mdsc->caps_reserve_count += have;
	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
					 mdsc->caps_reserve_count +
					 mdsc->caps_avail_count);
	spin_unlock(&mdsc->caps_list_lock);
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	for (i = have; i < need; i++) {
		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
		if (!cap) {
			ret = -ENOMEM;
			goto out_alloc_count;
		}
		list_add(&cap->caps_item, &newcaps);
		alloc++;
	}
	BUG_ON(have + alloc != need);

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	spin_lock(&mdsc->caps_list_lock);
	mdsc->caps_total_count += alloc;
	mdsc->caps_reserve_count += alloc;
	list_splice(&newcaps, &mdsc->caps_list);
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	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
					 mdsc->caps_reserve_count +
					 mdsc->caps_avail_count);
	spin_unlock(&mdsc->caps_list_lock);
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	ctx->count = need;
	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
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	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
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	return 0;

out_alloc_count:
	/* we didn't manage to reserve as much as we needed */
	pr_warning("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
		   ctx, need, have);
	return ret;
}

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int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
			struct ceph_cap_reservation *ctx)
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{
	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
	if (ctx->count) {
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		spin_lock(&mdsc->caps_list_lock);
		BUG_ON(mdsc->caps_reserve_count < ctx->count);
		mdsc->caps_reserve_count -= ctx->count;
		mdsc->caps_avail_count += ctx->count;
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		ctx->count = 0;
		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
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		     mdsc->caps_total_count, mdsc->caps_use_count,
		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
						 mdsc->caps_reserve_count +
						 mdsc->caps_avail_count);
		spin_unlock(&mdsc->caps_list_lock);
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	}
	return 0;
}

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static struct ceph_cap *get_cap(struct ceph_mds_client *mdsc,
				struct ceph_cap_reservation *ctx)
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{
	struct ceph_cap *cap = NULL;

	/* temporary, until we do something about cap import/export */
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	if (!ctx) {
		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
		if (cap) {
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			spin_lock(&mdsc->caps_list_lock);
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			mdsc->caps_use_count++;
			mdsc->caps_total_count++;
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			spin_unlock(&mdsc->caps_list_lock);
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		}
		return cap;
	}
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	spin_lock(&mdsc->caps_list_lock);
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	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
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	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
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	BUG_ON(!ctx->count);
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	BUG_ON(ctx->count > mdsc->caps_reserve_count);
	BUG_ON(list_empty(&mdsc->caps_list));
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	ctx->count--;
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	mdsc->caps_reserve_count--;
	mdsc->caps_use_count++;
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	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
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	list_del(&cap->caps_item);

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	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
	spin_unlock(&mdsc->caps_list_lock);
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	return cap;
}

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void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
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{
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	spin_lock(&mdsc->caps_list_lock);
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	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
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	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
	mdsc->caps_use_count--;
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	/*
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	 * Keep some preallocated caps around (ceph_min_count), to
	 * avoid lots of free/alloc churn.
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	 */
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	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
				      mdsc->caps_min_count) {
		mdsc->caps_total_count--;
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		kmem_cache_free(ceph_cap_cachep, cap);
	} else {
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		mdsc->caps_avail_count++;
		list_add(&cap->caps_item, &mdsc->caps_list);
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	}

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	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
	spin_unlock(&mdsc->caps_list_lock);
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}

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void ceph_reservation_status(struct ceph_fs_client *fsc,
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			     int *total, int *avail, int *used, int *reserved,
			     int *min)
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{
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	struct ceph_mds_client *mdsc = fsc->mdsc;
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	if (total)
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		*total = mdsc->caps_total_count;
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	if (avail)
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		*avail = mdsc->caps_avail_count;
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	if (used)
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		*used = mdsc->caps_use_count;
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	if (reserved)
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		*reserved = mdsc->caps_reserve_count;
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	if (min)
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		*min = mdsc->caps_min_count;
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}

/*
 * Find ceph_cap for given mds, if any.
 *
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 * Called with i_ceph_lock held.
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 */
static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
{
	struct ceph_cap *cap;
	struct rb_node *n = ci->i_caps.rb_node;

	while (n) {
		cap = rb_entry(n, struct ceph_cap, ci_node);
		if (mds < cap->mds)
			n = n->rb_left;
		else if (mds > cap->mds)
			n = n->rb_right;
		else
			return cap;
	}
	return NULL;
}

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struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
{
	struct ceph_cap *cap;

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	spin_lock(&ci->i_ceph_lock);
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	cap = __get_cap_for_mds(ci, mds);
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	spin_unlock(&ci->i_ceph_lock);
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	return cap;
}

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/*
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 * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
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 */
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static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
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{
	struct ceph_cap *cap;
	int mds = -1;
	struct rb_node *p;

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	/* prefer mds with WR|BUFFER|EXCL caps */
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	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		mds = cap->mds;
		if (cap->issued & (CEPH_CAP_FILE_WR |
				   CEPH_CAP_FILE_BUFFER |
				   CEPH_CAP_FILE_EXCL))
			break;
	}
	return mds;
}

int ceph_get_cap_mds(struct inode *inode)
{
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	struct ceph_inode_info *ci = ceph_inode(inode);
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	int mds;
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	spin_lock(&ci->i_ceph_lock);
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	mds = __ceph_get_cap_mds(ceph_inode(inode));
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	spin_unlock(&ci->i_ceph_lock);
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	return mds;
}

/*
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 * Called under i_ceph_lock.
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 */
static void __insert_cap_node(struct ceph_inode_info *ci,
			      struct ceph_cap *new)
{
	struct rb_node **p = &ci->i_caps.rb_node;
	struct rb_node *parent = NULL;
	struct ceph_cap *cap = NULL;

	while (*p) {
		parent = *p;
		cap = rb_entry(parent, struct ceph_cap, ci_node);
		if (new->mds < cap->mds)
			p = &(*p)->rb_left;
		else if (new->mds > cap->mds)
			p = &(*p)->rb_right;
		else
			BUG();
	}

	rb_link_node(&new->ci_node, parent, p);
	rb_insert_color(&new->ci_node, &ci->i_caps);
}

/*
 * (re)set cap hold timeouts, which control the delayed release
 * of unused caps back to the MDS.  Should be called on cap use.
 */
static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
			       struct ceph_inode_info *ci)
{
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	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
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	ci->i_hold_caps_min = round_jiffies(jiffies +
					    ma->caps_wanted_delay_min * HZ);
	ci->i_hold_caps_max = round_jiffies(jiffies +
					    ma->caps_wanted_delay_max * HZ);
	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
}

/*
 * (Re)queue cap at the end of the delayed cap release list.
 *
 * If I_FLUSH is set, leave the inode at the front of the list.
 *
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 * Caller holds i_ceph_lock
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 *    -> we take mdsc->cap_delay_lock
 */
static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
				struct ceph_inode_info *ci)
{
	__cap_set_timeouts(mdsc, ci);
	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
	     ci->i_ceph_flags, ci->i_hold_caps_max);
	if (!mdsc->stopping) {
		spin_lock(&mdsc->cap_delay_lock);
		if (!list_empty(&ci->i_cap_delay_list)) {
			if (ci->i_ceph_flags & CEPH_I_FLUSH)
				goto no_change;
			list_del_init(&ci->i_cap_delay_list);
		}
		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
no_change:
		spin_unlock(&mdsc->cap_delay_lock);
	}
}

/*
 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 * indicating we should send a cap message to flush dirty metadata
 * asap, and move to the front of the delayed cap list.
 */
static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
				      struct ceph_inode_info *ci)
{
	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
	spin_lock(&mdsc->cap_delay_lock);
	ci->i_ceph_flags |= CEPH_I_FLUSH;
	if (!list_empty(&ci->i_cap_delay_list))
		list_del_init(&ci->i_cap_delay_list);
	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
	spin_unlock(&mdsc->cap_delay_lock);
}

/*
 * Cancel delayed work on cap.
 *
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 * Caller must hold i_ceph_lock.
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 */
static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
			       struct ceph_inode_info *ci)
{
	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
	if (list_empty(&ci->i_cap_delay_list))
		return;
	spin_lock(&mdsc->cap_delay_lock);
	list_del_init(&ci->i_cap_delay_list);
	spin_unlock(&mdsc->cap_delay_lock);
}

/*
 * Common issue checks for add_cap, handle_cap_grant.
 */
static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
			      unsigned issued)
{
	unsigned had = __ceph_caps_issued(ci, NULL);

	/*
	 * Each time we receive FILE_CACHE anew, we increment
	 * i_rdcache_gen.
	 */
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	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
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		ci->i_rdcache_gen++;

	/*
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	 * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
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	 * don't know what happened to this directory while we didn't
	 * have the cap.
	 */
	if ((issued & CEPH_CAP_FILE_SHARED) &&
	    (had & CEPH_CAP_FILE_SHARED) == 0) {
		ci->i_shared_gen++;
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		if (S_ISDIR(ci->vfs_inode.i_mode))
			ceph_dir_clear_complete(&ci->vfs_inode);
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	}
}

/*
 * Add a capability under the given MDS session.
 *
 * Caller should hold session snap_rwsem (read) and s_mutex.
 *
 * @fmode is the open file mode, if we are opening a file, otherwise
 * it is < 0.  (This is so we can atomically add the cap and add an
 * open file reference to it.)
 */
int ceph_add_cap(struct inode *inode,
		 struct ceph_mds_session *session, u64 cap_id,
		 int fmode, unsigned issued, unsigned wanted,
		 unsigned seq, unsigned mseq, u64 realmino, int flags,
		 struct ceph_cap_reservation *caps_reservation)
{
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	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
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	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_cap *new_cap = NULL;
	struct ceph_cap *cap;
	int mds = session->s_mds;
	int actual_wanted;

	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
	     session->s_mds, cap_id, ceph_cap_string(issued), seq);

	/*
	 * If we are opening the file, include file mode wanted bits
	 * in wanted.
	 */
	if (fmode >= 0)
		wanted |= ceph_caps_for_mode(fmode);

retry:
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	spin_lock(&ci->i_ceph_lock);
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	cap = __get_cap_for_mds(ci, mds);
	if (!cap) {
		if (new_cap) {
			cap = new_cap;
			new_cap = NULL;
		} else {
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			spin_unlock(&ci->i_ceph_lock);
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			new_cap = get_cap(mdsc, caps_reservation);
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			if (new_cap == NULL)
				return -ENOMEM;
			goto retry;
		}

		cap->issued = 0;
		cap->implemented = 0;
		cap->mds = mds;
		cap->mds_wanted = 0;

		cap->ci = ci;
		__insert_cap_node(ci, cap);

		/* clear out old exporting info?  (i.e. on cap import) */
		if (ci->i_cap_exporting_mds == mds) {
			ci->i_cap_exporting_issued = 0;
			ci->i_cap_exporting_mseq = 0;
			ci->i_cap_exporting_mds = -1;
		}

		/* add to session cap list */
		cap->session = session;
		spin_lock(&session->s_cap_lock);
		list_add_tail(&cap->session_caps, &session->s_caps);
		session->s_nr_caps++;
		spin_unlock(&session->s_cap_lock);
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	} else if (new_cap)
		ceph_put_cap(mdsc, new_cap);
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	if (!ci->i_snap_realm) {
		/*
		 * add this inode to the appropriate snap realm
		 */
		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
							       realmino);
		if (realm) {
			ceph_get_snap_realm(mdsc, realm);
			spin_lock(&realm->inodes_with_caps_lock);
			ci->i_snap_realm = realm;
			list_add(&ci->i_snap_realm_item,
				 &realm->inodes_with_caps);
			spin_unlock(&realm->inodes_with_caps_lock);
		} else {
			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
			       realmino);
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			WARN_ON(!realm);
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		}
	}

	__check_cap_issue(ci, cap, issued);

	/*
	 * If we are issued caps we don't want, or the mds' wanted
	 * value appears to be off, queue a check so we'll release
	 * later and/or update the mds wanted value.
	 */
	actual_wanted = __ceph_caps_wanted(ci);
	if ((wanted & ~actual_wanted) ||
	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
		     ceph_cap_string(issued), ceph_cap_string(wanted),
		     ceph_cap_string(actual_wanted));
		__cap_delay_requeue(mdsc, ci);
	}

	if (flags & CEPH_CAP_FLAG_AUTH)
		ci->i_auth_cap = cap;
614
	else if (ci->i_auth_cap == cap) {
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		ci->i_auth_cap = NULL;
616 617 618 619 620 621 622 623
		spin_lock(&mdsc->cap_dirty_lock);
		if (!list_empty(&ci->i_dirty_item)) {
			dout(" moving %p to cap_dirty_migrating\n", inode);
			list_move(&ci->i_dirty_item,
				  &mdsc->cap_dirty_migrating);
		}
		spin_unlock(&mdsc->cap_dirty_lock);
	}
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	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
	     ceph_cap_string(issued|cap->issued), seq, mds);
	cap->cap_id = cap_id;
	cap->issued = issued;
	cap->implemented |= issued;
	cap->mds_wanted |= wanted;
	cap->seq = seq;
	cap->issue_seq = seq;
	cap->mseq = mseq;
635
	cap->cap_gen = session->s_cap_gen;
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	if (fmode >= 0)
		__ceph_get_fmode(ci, fmode);
639
	spin_unlock(&ci->i_ceph_lock);
640
	wake_up_all(&ci->i_cap_wq);
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	return 0;
}

/*
 * Return true if cap has not timed out and belongs to the current
 * generation of the MDS session (i.e. has not gone 'stale' due to
 * us losing touch with the mds).
 */
static int __cap_is_valid(struct ceph_cap *cap)
{
	unsigned long ttl;
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	u32 gen;
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654
	spin_lock(&cap->session->s_gen_ttl_lock);
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	gen = cap->session->s_cap_gen;
	ttl = cap->session->s_cap_ttl;
657
	spin_unlock(&cap->session->s_gen_ttl_lock);
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659
	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
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		dout("__cap_is_valid %p cap %p issued %s "
		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
662
		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
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		return 0;
	}

	return 1;
}

/*
 * Return set of valid cap bits issued to us.  Note that caps time
 * out, and may be invalidated in bulk if the client session times out
 * and session->s_cap_gen is bumped.
 */
int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
{
676
	int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
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	struct ceph_cap *cap;
	struct rb_node *p;

	if (implemented)
		*implemented = 0;
	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		if (!__cap_is_valid(cap))
			continue;
		dout("__ceph_caps_issued %p cap %p issued %s\n",
		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
		have |= cap->issued;
		if (implemented)
			*implemented |= cap->implemented;
	}
	return have;
}

/*
 * Get cap bits issued by caps other than @ocap
 */
int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
{
	int have = ci->i_snap_caps;
	struct ceph_cap *cap;
	struct rb_node *p;

	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		if (cap == ocap)
			continue;
		if (!__cap_is_valid(cap))
			continue;
		have |= cap->issued;
	}
	return have;
}

/*
 * Move a cap to the end of the LRU (oldest caps at list head, newest
 * at list tail).
 */
static void __touch_cap(struct ceph_cap *cap)
{
	struct ceph_mds_session *s = cap->session;

	spin_lock(&s->s_cap_lock);
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	if (s->s_cap_iterator == NULL) {
725 726 727 728 729 730 731
		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
		     s->s_mds);
		list_move_tail(&cap->session_caps, &s->s_caps);
	} else {
		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
		     &cap->ci->vfs_inode, cap, s->s_mds);
	}
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	spin_unlock(&s->s_cap_lock);
}

/*
 * Check if we hold the given mask.  If so, move the cap(s) to the
 * front of their respective LRUs.  (This is the preferred way for
 * callers to check for caps they want.)
 */
int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
{
	struct ceph_cap *cap;
	struct rb_node *p;
	int have = ci->i_snap_caps;

	if ((have & mask) == mask) {
		dout("__ceph_caps_issued_mask %p snap issued %s"
		     " (mask %s)\n", &ci->vfs_inode,
		     ceph_cap_string(have),
		     ceph_cap_string(mask));
		return 1;
	}

	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		if (!__cap_is_valid(cap))
			continue;
		if ((cap->issued & mask) == mask) {
			dout("__ceph_caps_issued_mask %p cap %p issued %s"
			     " (mask %s)\n", &ci->vfs_inode, cap,
			     ceph_cap_string(cap->issued),
			     ceph_cap_string(mask));
			if (touch)
				__touch_cap(cap);
			return 1;
		}

		/* does a combination of caps satisfy mask? */
		have |= cap->issued;
		if ((have & mask) == mask) {
			dout("__ceph_caps_issued_mask %p combo issued %s"
			     " (mask %s)\n", &ci->vfs_inode,
			     ceph_cap_string(cap->issued),
			     ceph_cap_string(mask));
			if (touch) {
				struct rb_node *q;

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				/* touch this + preceding caps */
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				__touch_cap(cap);
				for (q = rb_first(&ci->i_caps); q != p;
				     q = rb_next(q)) {
					cap = rb_entry(q, struct ceph_cap,
						       ci_node);
					if (!__cap_is_valid(cap))
						continue;
					__touch_cap(cap);
				}
			}
			return 1;
		}
	}

	return 0;
}

/*
 * Return true if mask caps are currently being revoked by an MDS.
 */
int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
{
	struct inode *inode = &ci->vfs_inode;
	struct ceph_cap *cap;
	struct rb_node *p;
	int ret = 0;

806
	spin_lock(&ci->i_ceph_lock);
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	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		if (__cap_is_valid(cap) &&
		    (cap->implemented & ~cap->issued & mask)) {
			ret = 1;
			break;
		}
	}
815
	spin_unlock(&ci->i_ceph_lock);
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	dout("ceph_caps_revoking %p %s = %d\n", inode,
	     ceph_cap_string(mask), ret);
	return ret;
}

int __ceph_caps_used(struct ceph_inode_info *ci)
{
	int used = 0;
	if (ci->i_pin_ref)
		used |= CEPH_CAP_PIN;
	if (ci->i_rd_ref)
		used |= CEPH_CAP_FILE_RD;
828
	if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
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		used |= CEPH_CAP_FILE_CACHE;
	if (ci->i_wr_ref)
		used |= CEPH_CAP_FILE_WR;
832
	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
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		used |= CEPH_CAP_FILE_BUFFER;
	return used;
}

/*
 * wanted, by virtue of open file modes
 */
int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
{
	int want = 0;
	int mode;
844
	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
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		if (ci->i_nr_by_mode[mode])
			want |= ceph_caps_for_mode(mode);
	return want;
}

/*
 * Return caps we have registered with the MDS(s) as 'wanted'.
 */
int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
{
	struct ceph_cap *cap;
	struct rb_node *p;
	int mds_wanted = 0;

	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		if (!__cap_is_valid(cap))
			continue;
		mds_wanted |= cap->mds_wanted;
	}
	return mds_wanted;
}

/*
869
 * called under i_ceph_lock
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 */
static int __ceph_is_any_caps(struct ceph_inode_info *ci)
{
	return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_mds >= 0;
}

/*
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 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
 *
879
 * caller should hold i_ceph_lock.
880
 * caller will not hold session s_mutex if called from destroy_inode.
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 */
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void __ceph_remove_cap(struct ceph_cap *cap)
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{
	struct ceph_mds_session *session = cap->session;
	struct ceph_inode_info *ci = cap->ci;
886
	struct ceph_mds_client *mdsc =
887
		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
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	int removed = 0;
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	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);

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	/* remove from session list */
	spin_lock(&session->s_cap_lock);
	if (session->s_cap_iterator == cap) {
		/* not yet, we are iterating over this very cap */
		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
		     cap, cap->session);
	} else {
		list_del_init(&cap->session_caps);
		session->s_nr_caps--;
		cap->session = NULL;
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		removed = 1;
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	}
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	/* protect backpointer with s_cap_lock: see iterate_session_caps */
	cap->ci = NULL;
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	spin_unlock(&session->s_cap_lock);

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	/* remove from inode list */
	rb_erase(&cap->ci_node, &ci->i_caps);
	if (ci->i_auth_cap == cap)
		ci->i_auth_cap = NULL;

	if (removed)
914
		ceph_put_cap(mdsc, cap);
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	if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
		struct ceph_snap_realm *realm = ci->i_snap_realm;
		spin_lock(&realm->inodes_with_caps_lock);
		list_del_init(&ci->i_snap_realm_item);
		ci->i_snap_realm_counter++;
		ci->i_snap_realm = NULL;
		spin_unlock(&realm->inodes_with_caps_lock);
		ceph_put_snap_realm(mdsc, realm);
	}
	if (!__ceph_is_any_real_caps(ci))
		__cap_delay_cancel(mdsc, ci);
}

/*
 * Build and send a cap message to the given MDS.
 *
 * Caller should be holding s_mutex.
 */
static int send_cap_msg(struct ceph_mds_session *session,
			u64 ino, u64 cid, int op,
			int caps, int wanted, int dirty,
			u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
			u64 size, u64 max_size,
			struct timespec *mtime, struct timespec *atime,
			u64 time_warp_seq,
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			uid_t uid, gid_t gid, umode_t mode,
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			u64 xattr_version,
			struct ceph_buffer *xattrs_buf,
			u64 follows)
{
	struct ceph_mds_caps *fc;
	struct ceph_msg *msg;

	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
	     " seq %u/%u mseq %u follows %lld size %llu/%llu"
	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
	     cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
	     ceph_cap_string(dirty),
	     seq, issue_seq, mseq, follows, size, max_size,
	     xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);

957
	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc), GFP_NOFS, false);
958 959
	if (!msg)
		return -ENOMEM;
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961
	msg->hdr.tid = cpu_to_le64(flush_tid);
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963
	fc = msg->front.iov_base;
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	memset(fc, 0, sizeof(*fc));

	fc->cap_id = cpu_to_le64(cid);
	fc->op = cpu_to_le32(op);
	fc->seq = cpu_to_le32(seq);
	fc->issue_seq = cpu_to_le32(issue_seq);
	fc->migrate_seq = cpu_to_le32(mseq);
	fc->caps = cpu_to_le32(caps);
	fc->wanted = cpu_to_le32(wanted);
	fc->dirty = cpu_to_le32(dirty);
	fc->ino = cpu_to_le64(ino);
	fc->snap_follows = cpu_to_le64(follows);

	fc->size = cpu_to_le64(size);
	fc->max_size = cpu_to_le64(max_size);
	if (mtime)
		ceph_encode_timespec(&fc->mtime, mtime);
	if (atime)
		ceph_encode_timespec(&fc->atime, atime);
	fc->time_warp_seq = cpu_to_le32(time_warp_seq);

	fc->uid = cpu_to_le32(uid);
	fc->gid = cpu_to_le32(gid);
	fc->mode = cpu_to_le32(mode);

	fc->xattr_version = cpu_to_le64(xattr_version);
	if (xattrs_buf) {
		msg->middle = ceph_buffer_get(xattrs_buf);
		fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
		msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
	}

	ceph_con_send(&session->s_con, msg);
	return 0;
}

1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
static void __queue_cap_release(struct ceph_mds_session *session,
				u64 ino, u64 cap_id, u32 migrate_seq,
				u32 issue_seq)
{
	struct ceph_msg *msg;
	struct ceph_mds_cap_release *head;
	struct ceph_mds_cap_item *item;

	spin_lock(&session->s_cap_lock);
	BUG_ON(!session->s_num_cap_releases);
	msg = list_first_entry(&session->s_cap_releases,
			       struct ceph_msg, list_head);

	dout(" adding %llx release to mds%d msg %p (%d left)\n",
	     ino, session->s_mds, msg, session->s_num_cap_releases);

	BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
	head = msg->front.iov_base;
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	le32_add_cpu(&head->num, 1);
1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039
	item = msg->front.iov_base + msg->front.iov_len;
	item->ino = cpu_to_le64(ino);
	item->cap_id = cpu_to_le64(cap_id);
	item->migrate_seq = cpu_to_le32(migrate_seq);
	item->seq = cpu_to_le32(issue_seq);

	session->s_num_cap_releases--;

	msg->front.iov_len += sizeof(*item);
	if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
		dout(" release msg %p full\n", msg);
		list_move_tail(&msg->list_head, &session->s_cap_releases_done);
	} else {
		dout(" release msg %p at %d/%d (%d)\n", msg,
		     (int)le32_to_cpu(head->num),
		     (int)CEPH_CAPS_PER_RELEASE,
		     (int)msg->front.iov_len);
	}
	spin_unlock(&session->s_cap_lock);
}

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/*
1041
 * Queue cap releases when an inode is dropped from our cache.  Since
1042
 * inode is about to be destroyed, there is no need for i_ceph_lock.
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 */
void ceph_queue_caps_release(struct inode *inode)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct rb_node *p;

	p = rb_first(&ci->i_caps);
	while (p) {
		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
		struct ceph_mds_session *session = cap->session;

1054 1055
		__queue_cap_release(session, ceph_ino(inode), cap->cap_id,
				    cap->mseq, cap->issue_seq);
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		p = rb_next(p);
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		__ceph_remove_cap(cap);
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	}
}

/*
 * Send a cap msg on the given inode.  Update our caps state, then
1063
 * drop i_ceph_lock and send the message.
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 *
 * Make note of max_size reported/requested from mds, revoked caps
 * that have now been implemented.
 *
 * Make half-hearted attempt ot to invalidate page cache if we are
 * dropping RDCACHE.  Note that this will leave behind locked pages
 * that we'll then need to deal with elsewhere.
 *
 * Return non-zero if delayed release, or we experienced an error
 * such that the caller should requeue + retry later.
 *
1075
 * called with i_ceph_lock, then drops it.
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 * caller should hold snap_rwsem (read), s_mutex.
 */
static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
		      int op, int used, int want, int retain, int flushing,
		      unsigned *pflush_tid)
1081
	__releases(cap->ci->i_ceph_lock)
S
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1082 1083 1084 1085
{
	struct ceph_inode_info *ci = cap->ci;
	struct inode *inode = &ci->vfs_inode;
	u64 cap_id = cap->cap_id;
1086
	int held, revoking, dropping, keep;
S
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1087 1088 1089 1090
	u64 seq, issue_seq, mseq, time_warp_seq, follows;
	u64 size, max_size;
	struct timespec mtime, atime;
	int wake = 0;
A
Al Viro 已提交
1091
	umode_t mode;
S
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1092 1093 1094 1095
	uid_t uid;
	gid_t gid;
	struct ceph_mds_session *session;
	u64 xattr_version = 0;
S
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1096
	struct ceph_buffer *xattr_blob = NULL;
S
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1097 1098 1099 1100 1101
	int delayed = 0;
	u64 flush_tid = 0;
	int i;
	int ret;

1102 1103 1104 1105 1106
	held = cap->issued | cap->implemented;
	revoking = cap->implemented & ~cap->issued;
	retain &= ~revoking;
	dropping = cap->issued & ~retain;

S
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1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156
	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
	     inode, cap, cap->session,
	     ceph_cap_string(held), ceph_cap_string(held & retain),
	     ceph_cap_string(revoking));
	BUG_ON((retain & CEPH_CAP_PIN) == 0);

	session = cap->session;

	/* don't release wanted unless we've waited a bit. */
	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
	    time_before(jiffies, ci->i_hold_caps_min)) {
		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
		     ceph_cap_string(cap->issued),
		     ceph_cap_string(cap->issued & retain),
		     ceph_cap_string(cap->mds_wanted),
		     ceph_cap_string(want));
		want |= cap->mds_wanted;
		retain |= cap->issued;
		delayed = 1;
	}
	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);

	cap->issued &= retain;  /* drop bits we don't want */
	if (cap->implemented & ~cap->issued) {
		/*
		 * Wake up any waiters on wanted -> needed transition.
		 * This is due to the weird transition from buffered
		 * to sync IO... we need to flush dirty pages _before_
		 * allowing sync writes to avoid reordering.
		 */
		wake = 1;
	}
	cap->implemented &= cap->issued | used;
	cap->mds_wanted = want;

	if (flushing) {
		/*
		 * assign a tid for flush operations so we can avoid
		 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
		 * clean type races.  track latest tid for every bit
		 * so we can handle flush AxFw, flush Fw, and have the
		 * first ack clean Ax.
		 */
		flush_tid = ++ci->i_cap_flush_last_tid;
		if (pflush_tid)
			*pflush_tid = flush_tid;
		dout(" cap_flush_tid %d\n", (int)flush_tid);
		for (i = 0; i < CEPH_CAP_BITS; i++)
			if (flushing & (1 << i))
				ci->i_cap_flush_tid[i] = flush_tid;
1157 1158 1159 1160

		follows = ci->i_head_snapc->seq;
	} else {
		follows = 0;
S
Sage Weil 已提交
1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
	}

	keep = cap->implemented;
	seq = cap->seq;
	issue_seq = cap->issue_seq;
	mseq = cap->mseq;
	size = inode->i_size;
	ci->i_reported_size = size;
	max_size = ci->i_wanted_max_size;
	ci->i_requested_max_size = max_size;
	mtime = inode->i_mtime;
	atime = inode->i_atime;
	time_warp_seq = ci->i_time_warp_seq;
	uid = inode->i_uid;
	gid = inode->i_gid;
	mode = inode->i_mode;

S
Sage Weil 已提交
1178
	if (flushing & CEPH_CAP_XATTR_EXCL) {
S
Sage Weil 已提交
1179
		__ceph_build_xattrs_blob(ci);
S
Sage Weil 已提交
1180 1181
		xattr_blob = ci->i_xattrs.blob;
		xattr_version = ci->i_xattrs.version;
S
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1182 1183
	}

1184
	spin_unlock(&ci->i_ceph_lock);
S
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1185 1186 1187 1188

	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
		size, max_size, &mtime, &atime, time_warp_seq,
S
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1189
		uid, gid, mode, xattr_version, xattr_blob,
S
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1190 1191 1192 1193 1194 1195 1196
		follows);
	if (ret < 0) {
		dout("error sending cap msg, must requeue %p\n", inode);
		delayed = 1;
	}

	if (wake)
1197
		wake_up_all(&ci->i_cap_wq);
S
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1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208

	return delayed;
}

/*
 * When a snapshot is taken, clients accumulate dirty metadata on
 * inodes with capabilities in ceph_cap_snaps to describe the file
 * state at the time the snapshot was taken.  This must be flushed
 * asynchronously back to the MDS once sync writes complete and dirty
 * data is written out.
 *
1209 1210 1211
 * Unless @again is true, skip cap_snaps that were already sent to
 * the MDS (i.e., during this session).
 *
1212
 * Called under i_ceph_lock.  Takes s_mutex as needed.
S
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1213 1214
 */
void __ceph_flush_snaps(struct ceph_inode_info *ci,
1215 1216
			struct ceph_mds_session **psession,
			int again)
1217 1218
		__releases(ci->i_ceph_lock)
		__acquires(ci->i_ceph_lock)
S
Sage Weil 已提交
1219 1220 1221 1222 1223
{
	struct inode *inode = &ci->vfs_inode;
	int mds;
	struct ceph_cap_snap *capsnap;
	u32 mseq;
1224
	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
S
Sage Weil 已提交
1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244
	struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
						    session->s_mutex */
	u64 next_follows = 0;  /* keep track of how far we've gotten through the
			     i_cap_snaps list, and skip these entries next time
			     around to avoid an infinite loop */

	if (psession)
		session = *psession;

	dout("__flush_snaps %p\n", inode);
retry:
	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
		/* avoid an infiniute loop after retry */
		if (capsnap->follows < next_follows)
			continue;
		/*
		 * we need to wait for sync writes to complete and for dirty
		 * pages to be written out.
		 */
		if (capsnap->dirty_pages || capsnap->writing)
1245
			break;
S
Sage Weil 已提交
1246

1247 1248 1249 1250 1251 1252
		/*
		 * if cap writeback already occurred, we should have dropped
		 * the capsnap in ceph_put_wrbuffer_cap_refs.
		 */
		BUG_ON(capsnap->dirty == 0);

S
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1253
		/* pick mds, take s_mutex */
1254 1255 1256 1257
		if (ci->i_auth_cap == NULL) {
			dout("no auth cap (migrating?), doing nothing\n");
			goto out;
		}
1258 1259 1260 1261 1262 1263 1264

		/* only flush each capsnap once */
		if (!again && !list_empty(&capsnap->flushing_item)) {
			dout("already flushed %p, skipping\n", capsnap);
			continue;
		}

1265 1266 1267
		mds = ci->i_auth_cap->session->s_mds;
		mseq = ci->i_auth_cap->mseq;

S
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1268 1269 1270 1271 1272 1273 1274
		if (session && session->s_mds != mds) {
			dout("oops, wrong session %p mutex\n", session);
			mutex_unlock(&session->s_mutex);
			ceph_put_mds_session(session);
			session = NULL;
		}
		if (!session) {
1275
			spin_unlock(&ci->i_ceph_lock);
S
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1276 1277 1278 1279 1280 1281 1282 1283 1284 1285
			mutex_lock(&mdsc->mutex);
			session = __ceph_lookup_mds_session(mdsc, mds);
			mutex_unlock(&mdsc->mutex);
			if (session) {
				dout("inverting session/ino locks on %p\n",
				     session);
				mutex_lock(&session->s_mutex);
			}
			/*
			 * if session == NULL, we raced against a cap
1286 1287
			 * deletion or migration.  retry, and we'll
			 * get a better @mds value next time.
S
Sage Weil 已提交
1288
			 */
1289
			spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1290 1291 1292 1293 1294 1295 1296 1297 1298
			goto retry;
		}

		capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
		atomic_inc(&capsnap->nref);
		if (!list_empty(&capsnap->flushing_item))
			list_del_init(&capsnap->flushing_item);
		list_add_tail(&capsnap->flushing_item,
			      &session->s_cap_snaps_flushing);
1299
		spin_unlock(&ci->i_ceph_lock);
S
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1300

1301 1302
		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
S
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1303 1304 1305 1306 1307 1308 1309
		send_cap_msg(session, ceph_vino(inode).ino, 0,
			     CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
			     capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
			     capsnap->size, 0,
			     &capsnap->mtime, &capsnap->atime,
			     capsnap->time_warp_seq,
			     capsnap->uid, capsnap->gid, capsnap->mode,
1310
			     capsnap->xattr_version, capsnap->xattr_blob,
S
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1311 1312 1313 1314 1315
			     capsnap->follows);

		next_follows = capsnap->follows + 1;
		ceph_put_cap_snap(capsnap);

1316
		spin_lock(&ci->i_ceph_lock);
S
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1317 1318 1319 1320 1321 1322 1323 1324
		goto retry;
	}

	/* we flushed them all; remove this inode from the queue */
	spin_lock(&mdsc->snap_flush_lock);
	list_del_init(&ci->i_snap_flush_item);
	spin_unlock(&mdsc->snap_flush_lock);

1325
out:
S
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1326 1327 1328 1329 1330 1331 1332 1333 1334 1335
	if (psession)
		*psession = session;
	else if (session) {
		mutex_unlock(&session->s_mutex);
		ceph_put_mds_session(session);
	}
}

static void ceph_flush_snaps(struct ceph_inode_info *ci)
{
1336
	spin_lock(&ci->i_ceph_lock);
1337
	__ceph_flush_snaps(ci, NULL, 0);
1338
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1339 1340
}

S
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1341
/*
1342 1343 1344
 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
 * Caller is then responsible for calling __mark_inode_dirty with the
 * returned flags value.
S
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1345
 */
1346
int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
S
Sage Weil 已提交
1347
{
1348
	struct ceph_mds_client *mdsc =
1349
		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
S
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1350 1351 1352 1353 1354 1355 1356 1357 1358
	struct inode *inode = &ci->vfs_inode;
	int was = ci->i_dirty_caps;
	int dirty = 0;

	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
	     ceph_cap_string(mask), ceph_cap_string(was),
	     ceph_cap_string(was | mask));
	ci->i_dirty_caps |= mask;
	if (was == 0) {
1359 1360 1361
		if (!ci->i_head_snapc)
			ci->i_head_snapc = ceph_get_snap_context(
				ci->i_snap_realm->cached_context);
1362 1363
		dout(" inode %p now dirty snapc %p auth cap %p\n",
		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
S
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1364 1365
		BUG_ON(!list_empty(&ci->i_dirty_item));
		spin_lock(&mdsc->cap_dirty_lock);
1366 1367 1368 1369 1370
		if (ci->i_auth_cap)
			list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
		else
			list_add(&ci->i_dirty_item,
				 &mdsc->cap_dirty_migrating);
S
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1371 1372
		spin_unlock(&mdsc->cap_dirty_lock);
		if (ci->i_flushing_caps == 0) {
1373
			ihold(inode);
S
Sage Weil 已提交
1374 1375 1376 1377 1378 1379 1380 1381
			dirty |= I_DIRTY_SYNC;
		}
	}
	BUG_ON(list_empty(&ci->i_dirty_item));
	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
	    (mask & CEPH_CAP_FILE_BUFFER))
		dirty |= I_DIRTY_DATASYNC;
	__cap_delay_requeue(mdsc, ci);
1382
	return dirty;
S
Sage Weil 已提交
1383 1384
}

S
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1385 1386 1387
/*
 * Add dirty inode to the flushing list.  Assigned a seq number so we
 * can wait for caps to flush without starving.
1388
 *
1389
 * Called under i_ceph_lock.
S
Sage Weil 已提交
1390
 */
1391
static int __mark_caps_flushing(struct inode *inode,
S
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1392 1393
				 struct ceph_mds_session *session)
{
1394
	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
S
Sage Weil 已提交
1395
	struct ceph_inode_info *ci = ceph_inode(inode);
1396
	int flushing;
S
Sage Weil 已提交
1397

1398
	BUG_ON(ci->i_dirty_caps == 0);
S
Sage Weil 已提交
1399
	BUG_ON(list_empty(&ci->i_dirty_item));
1400 1401 1402 1403 1404 1405 1406 1407

	flushing = ci->i_dirty_caps;
	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
	     ceph_cap_string(flushing),
	     ceph_cap_string(ci->i_flushing_caps),
	     ceph_cap_string(ci->i_flushing_caps | flushing));
	ci->i_flushing_caps |= flushing;
	ci->i_dirty_caps = 0;
1408
	dout(" inode %p now !dirty\n", inode);
1409

S
Sage Weil 已提交
1410
	spin_lock(&mdsc->cap_dirty_lock);
1411 1412 1413
	list_del_init(&ci->i_dirty_item);

	ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
S
Sage Weil 已提交
1414 1415 1416
	if (list_empty(&ci->i_flushing_item)) {
		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
		mdsc->num_cap_flushing++;
1417 1418 1419 1420 1421
		dout(" inode %p now flushing seq %lld\n", inode,
		     ci->i_cap_flush_seq);
	} else {
		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
		dout(" inode %p now flushing (more) seq %lld\n", inode,
S
Sage Weil 已提交
1422 1423 1424
		     ci->i_cap_flush_seq);
	}
	spin_unlock(&mdsc->cap_dirty_lock);
1425 1426

	return flushing;
S
Sage Weil 已提交
1427 1428
}

1429 1430 1431 1432 1433 1434 1435 1436
/*
 * try to invalidate mapping pages without blocking.
 */
static int try_nonblocking_invalidate(struct inode *inode)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	u32 invalidating_gen = ci->i_rdcache_gen;

1437
	spin_unlock(&ci->i_ceph_lock);
1438
	invalidate_mapping_pages(&inode->i_data, 0, -1);
1439
	spin_lock(&ci->i_ceph_lock);
1440

1441
	if (inode->i_data.nrpages == 0 &&
1442 1443 1444
	    invalidating_gen == ci->i_rdcache_gen) {
		/* success. */
		dout("try_nonblocking_invalidate %p success\n", inode);
1445 1446
		/* save any racing async invalidate some trouble */
		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1447 1448 1449 1450 1451 1452
		return 0;
	}
	dout("try_nonblocking_invalidate %p failed\n", inode);
	return -1;
}

S
Sage Weil 已提交
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466
/*
 * Swiss army knife function to examine currently used and wanted
 * versus held caps.  Release, flush, ack revoked caps to mds as
 * appropriate.
 *
 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
 *    cap release further.
 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
 *    further delay.
 */
void ceph_check_caps(struct ceph_inode_info *ci, int flags,
		     struct ceph_mds_session *session)
{
1467 1468
	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
	struct ceph_mds_client *mdsc = fsc->mdsc;
S
Sage Weil 已提交
1469 1470
	struct inode *inode = &ci->vfs_inode;
	struct ceph_cap *cap;
1471
	int file_wanted, used, cap_used;
S
Sage Weil 已提交
1472
	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
S
Sage Weil 已提交
1473
	int issued, implemented, want, retain, revoking, flushing = 0;
S
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1474 1475 1476 1477 1478
	int mds = -1;   /* keep track of how far we've gone through i_caps list
			   to avoid an infinite loop on retry */
	struct rb_node *p;
	int tried_invalidate = 0;
	int delayed = 0, sent = 0, force_requeue = 0, num;
S
Sage Weil 已提交
1479
	int queue_invalidate = 0;
S
Sage Weil 已提交
1480 1481 1482 1483 1484 1485
	int is_delayed = flags & CHECK_CAPS_NODELAY;

	/* if we are unmounting, flush any unused caps immediately. */
	if (mdsc->stopping)
		is_delayed = 1;

1486
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1487 1488 1489 1490 1491 1492

	if (ci->i_ceph_flags & CEPH_I_FLUSH)
		flags |= CHECK_CAPS_FLUSH;

	/* flush snaps first time around only */
	if (!list_empty(&ci->i_cap_snaps))
1493
		__ceph_flush_snaps(ci, &session, 0);
S
Sage Weil 已提交
1494 1495
	goto retry_locked;
retry:
1496
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1497 1498 1499 1500
retry_locked:
	file_wanted = __ceph_caps_file_wanted(ci);
	used = __ceph_caps_used(ci);
	want = file_wanted | used;
S
Sage Weil 已提交
1501 1502
	issued = __ceph_caps_issued(ci, &implemented);
	revoking = implemented & ~issued;
S
Sage Weil 已提交
1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520

	retain = want | CEPH_CAP_PIN;
	if (!mdsc->stopping && inode->i_nlink > 0) {
		if (want) {
			retain |= CEPH_CAP_ANY;       /* be greedy */
		} else {
			retain |= CEPH_CAP_ANY_SHARED;
			/*
			 * keep RD only if we didn't have the file open RW,
			 * because then the mds would revoke it anyway to
			 * journal max_size=0.
			 */
			if (ci->i_max_size == 0)
				retain |= CEPH_CAP_ANY_RD;
		}
	}

	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
S
Sage Weil 已提交
1521
	     " issued %s revoking %s retain %s %s%s%s\n", inode,
S
Sage Weil 已提交
1522 1523 1524
	     ceph_cap_string(file_wanted),
	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
	     ceph_cap_string(ci->i_flushing_caps),
S
Sage Weil 已提交
1525
	     ceph_cap_string(issued), ceph_cap_string(revoking),
S
Sage Weil 已提交
1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
	     ceph_cap_string(retain),
	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");

	/*
	 * If we no longer need to hold onto old our caps, and we may
	 * have cached pages, but don't want them, then try to invalidate.
	 * If we fail, it's because pages are locked.... try again later.
	 */
	if ((!is_delayed || mdsc->stopping) &&
	    ci->i_wrbuffer_ref == 0 &&               /* no dirty pages... */
1538
	    inode->i_data.nrpages &&                 /* have cached pages */
S
Sage Weil 已提交
1539
	    (file_wanted == 0 ||                     /* no open files */
1540 1541
	     (revoking & (CEPH_CAP_FILE_CACHE|
			  CEPH_CAP_FILE_LAZYIO))) && /*  or revoking cache */
S
Sage Weil 已提交
1542 1543
	    !tried_invalidate) {
		dout("check_caps trying to invalidate on %p\n", inode);
1544
		if (try_nonblocking_invalidate(inode) < 0) {
1545 1546
			if (revoking & (CEPH_CAP_FILE_CACHE|
					CEPH_CAP_FILE_LAZYIO)) {
1547 1548 1549 1550 1551 1552 1553 1554 1555 1556
				dout("check_caps queuing invalidate\n");
				queue_invalidate = 1;
				ci->i_rdcache_revoking = ci->i_rdcache_gen;
			} else {
				dout("check_caps failed to invalidate pages\n");
				/* we failed to invalidate pages.  check these
				   caps again later. */
				force_requeue = 1;
				__cap_set_timeouts(mdsc, ci);
			}
S
Sage Weil 已提交
1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573
		}
		tried_invalidate = 1;
		goto retry_locked;
	}

	num = 0;
	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		cap = rb_entry(p, struct ceph_cap, ci_node);
		num++;

		/* avoid looping forever */
		if (mds >= cap->mds ||
		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
			continue;

		/* NOTE: no side-effects allowed, until we take s_mutex */

1574 1575 1576 1577
		cap_used = used;
		if (ci->i_auth_cap && cap != ci->i_auth_cap)
			cap_used &= ~ci->i_auth_cap->issued;

S
Sage Weil 已提交
1578
		revoking = cap->implemented & ~cap->issued;
1579
		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
1580
		     cap->mds, cap, ceph_cap_string(cap->issued),
1581
		     ceph_cap_string(cap_used),
1582 1583
		     ceph_cap_string(cap->implemented),
		     ceph_cap_string(revoking));
S
Sage Weil 已提交
1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608

		if (cap == ci->i_auth_cap &&
		    (cap->issued & CEPH_CAP_FILE_WR)) {
			/* request larger max_size from MDS? */
			if (ci->i_wanted_max_size > ci->i_max_size &&
			    ci->i_wanted_max_size > ci->i_requested_max_size) {
				dout("requesting new max_size\n");
				goto ack;
			}

			/* approaching file_max? */
			if ((inode->i_size << 1) >= ci->i_max_size &&
			    (ci->i_reported_size << 1) < ci->i_max_size) {
				dout("i_size approaching max_size\n");
				goto ack;
			}
		}
		/* flush anything dirty? */
		if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
		    ci->i_dirty_caps) {
			dout("flushing dirty caps\n");
			goto ack;
		}

		/* completed revocation? going down and there are no caps? */
1609
		if (revoking && (revoking & cap_used) == 0) {
S
Sage Weil 已提交
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639
			dout("completed revocation of %s\n",
			     ceph_cap_string(cap->implemented & ~cap->issued));
			goto ack;
		}

		/* want more caps from mds? */
		if (want & ~(cap->mds_wanted | cap->issued))
			goto ack;

		/* things we might delay */
		if ((cap->issued & ~retain) == 0 &&
		    cap->mds_wanted == want)
			continue;     /* nope, all good */

		if (is_delayed)
			goto ack;

		/* delay? */
		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
		    time_before(jiffies, ci->i_hold_caps_max)) {
			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
			     ceph_cap_string(cap->issued),
			     ceph_cap_string(cap->issued & retain),
			     ceph_cap_string(cap->mds_wanted),
			     ceph_cap_string(want));
			delayed++;
			continue;
		}

ack:
1640 1641 1642 1643 1644
		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
			dout(" skipping %p I_NOFLUSH set\n", inode);
			continue;
		}

S
Sage Weil 已提交
1645 1646 1647 1648 1649 1650 1651 1652 1653 1654
		if (session && session != cap->session) {
			dout("oops, wrong session %p mutex\n", session);
			mutex_unlock(&session->s_mutex);
			session = NULL;
		}
		if (!session) {
			session = cap->session;
			if (mutex_trylock(&session->s_mutex) == 0) {
				dout("inverting session/ino locks on %p\n",
				     session);
1655
				spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668
				if (took_snap_rwsem) {
					up_read(&mdsc->snap_rwsem);
					took_snap_rwsem = 0;
				}
				mutex_lock(&session->s_mutex);
				goto retry;
			}
		}
		/* take snap_rwsem after session mutex */
		if (!took_snap_rwsem) {
			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
				dout("inverting snap/in locks on %p\n",
				     inode);
1669
				spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1670 1671 1672 1673 1674 1675 1676
				down_read(&mdsc->snap_rwsem);
				took_snap_rwsem = 1;
				goto retry;
			}
			took_snap_rwsem = 1;
		}

1677 1678
		if (cap == ci->i_auth_cap && ci->i_dirty_caps)
			flushing = __mark_caps_flushing(inode, session);
1679 1680
		else
			flushing = 0;
S
Sage Weil 已提交
1681 1682 1683 1684

		mds = cap->mds;  /* remember mds, so we don't repeat */
		sent++;

1685
		/* __send_cap drops i_ceph_lock */
1686 1687
		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, cap_used,
				      want, retain, flushing, NULL);
1688
		goto retry; /* retake i_ceph_lock and restart our cap scan. */
S
Sage Weil 已提交
1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701
	}

	/*
	 * Reschedule delayed caps release if we delayed anything,
	 * otherwise cancel.
	 */
	if (delayed && is_delayed)
		force_requeue = 1;   /* __send_cap delayed release; requeue */
	if (!delayed && !is_delayed)
		__cap_delay_cancel(mdsc, ci);
	else if (!is_delayed || force_requeue)
		__cap_delay_requeue(mdsc, ci);

1702
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1703

S
Sage Weil 已提交
1704
	if (queue_invalidate)
1705
		ceph_queue_invalidate(inode);
S
Sage Weil 已提交
1706

1707
	if (session)
S
Sage Weil 已提交
1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718
		mutex_unlock(&session->s_mutex);
	if (took_snap_rwsem)
		up_read(&mdsc->snap_rwsem);
}

/*
 * Try to flush dirty caps back to the auth mds.
 */
static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
			  unsigned *flush_tid)
{
1719
	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
S
Sage Weil 已提交
1720 1721 1722 1723 1724
	struct ceph_inode_info *ci = ceph_inode(inode);
	int unlock_session = session ? 0 : 1;
	int flushing = 0;

retry:
1725
	spin_lock(&ci->i_ceph_lock);
1726 1727 1728 1729
	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
		goto out;
	}
S
Sage Weil 已提交
1730 1731 1732 1733 1734 1735 1736
	if (ci->i_dirty_caps && ci->i_auth_cap) {
		struct ceph_cap *cap = ci->i_auth_cap;
		int used = __ceph_caps_used(ci);
		int want = __ceph_caps_wanted(ci);
		int delayed;

		if (!session) {
1737
			spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1738 1739 1740 1741 1742 1743 1744 1745
			session = cap->session;
			mutex_lock(&session->s_mutex);
			goto retry;
		}
		BUG_ON(session != cap->session);
		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
			goto out;

1746
		flushing = __mark_caps_flushing(inode, session);
S
Sage Weil 已提交
1747

1748
		/* __send_cap drops i_ceph_lock */
S
Sage Weil 已提交
1749 1750 1751 1752 1753 1754
		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
				     cap->issued | cap->implemented, flushing,
				     flush_tid);
		if (!delayed)
			goto out_unlocked;

1755
		spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1756 1757 1758
		__cap_delay_requeue(mdsc, ci);
	}
out:
1759
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771
out_unlocked:
	if (session && unlock_session)
		mutex_unlock(&session->s_mutex);
	return flushing;
}

/*
 * Return true if we've flushed caps through the given flush_tid.
 */
static int caps_are_flushed(struct inode *inode, unsigned tid)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
1772
	int i, ret = 1;
S
Sage Weil 已提交
1773

1774
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1775 1776 1777 1778 1779 1780 1781
	for (i = 0; i < CEPH_CAP_BITS; i++)
		if ((ci->i_flushing_caps & (1 << i)) &&
		    ci->i_cap_flush_tid[i] <= tid) {
			/* still flushing this bit */
			ret = 0;
			break;
		}
1782
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829
	return ret;
}

/*
 * Wait on any unsafe replies for the given inode.  First wait on the
 * newest request, and make that the upper bound.  Then, if there are
 * more requests, keep waiting on the oldest as long as it is still older
 * than the original request.
 */
static void sync_write_wait(struct inode *inode)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct list_head *head = &ci->i_unsafe_writes;
	struct ceph_osd_request *req;
	u64 last_tid;

	spin_lock(&ci->i_unsafe_lock);
	if (list_empty(head))
		goto out;

	/* set upper bound as _last_ entry in chain */
	req = list_entry(head->prev, struct ceph_osd_request,
			 r_unsafe_item);
	last_tid = req->r_tid;

	do {
		ceph_osdc_get_request(req);
		spin_unlock(&ci->i_unsafe_lock);
		dout("sync_write_wait on tid %llu (until %llu)\n",
		     req->r_tid, last_tid);
		wait_for_completion(&req->r_safe_completion);
		spin_lock(&ci->i_unsafe_lock);
		ceph_osdc_put_request(req);

		/*
		 * from here on look at first entry in chain, since we
		 * only want to wait for anything older than last_tid
		 */
		if (list_empty(head))
			break;
		req = list_entry(head->next, struct ceph_osd_request,
				 r_unsafe_item);
	} while (req->r_tid < last_tid);
out:
	spin_unlock(&ci->i_unsafe_lock);
}

1830
int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
S
Sage Weil 已提交
1831
{
1832
	struct inode *inode = file->f_mapping->host;
S
Sage Weil 已提交
1833 1834 1835 1836 1837 1838 1839 1840
	struct ceph_inode_info *ci = ceph_inode(inode);
	unsigned flush_tid;
	int ret;
	int dirty;

	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
	sync_write_wait(inode);

1841
	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
S
Sage Weil 已提交
1842 1843
	if (ret < 0)
		return ret;
1844
	mutex_lock(&inode->i_mutex);
S
Sage Weil 已提交
1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860

	dirty = try_flush_caps(inode, NULL, &flush_tid);
	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));

	/*
	 * only wait on non-file metadata writeback (the mds
	 * can recover size and mtime, so we don't need to
	 * wait for that)
	 */
	if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
		dout("fsync waiting for flush_tid %u\n", flush_tid);
		ret = wait_event_interruptible(ci->i_cap_wq,
				       caps_are_flushed(inode, flush_tid));
	}

	dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
1861
	mutex_unlock(&inode->i_mutex);
S
Sage Weil 已提交
1862 1863 1864 1865 1866 1867 1868 1869 1870
	return ret;
}

/*
 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
 * queue inode for flush but don't do so immediately, because we can
 * get by with fewer MDS messages if we wait for data writeback to
 * complete first.
 */
1871
int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
S
Sage Weil 已提交
1872 1873 1874 1875 1876
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	unsigned flush_tid;
	int err = 0;
	int dirty;
1877
	int wait = wbc->sync_mode == WB_SYNC_ALL;
S
Sage Weil 已提交
1878 1879 1880 1881 1882 1883 1884 1885

	dout("write_inode %p wait=%d\n", inode, wait);
	if (wait) {
		dirty = try_flush_caps(inode, NULL, &flush_tid);
		if (dirty)
			err = wait_event_interruptible(ci->i_cap_wq,
				       caps_are_flushed(inode, flush_tid));
	} else {
1886
		struct ceph_mds_client *mdsc =
1887
			ceph_sb_to_client(inode->i_sb)->mdsc;
S
Sage Weil 已提交
1888

1889
		spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1890 1891
		if (__ceph_caps_dirty(ci))
			__cap_delay_requeue_front(mdsc, ci);
1892
		spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914
	}
	return err;
}

/*
 * After a recovering MDS goes active, we need to resend any caps
 * we were flushing.
 *
 * Caller holds session->s_mutex.
 */
static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
				   struct ceph_mds_session *session)
{
	struct ceph_cap_snap *capsnap;

	dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
	list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
			    flushing_item) {
		struct ceph_inode_info *ci = capsnap->ci;
		struct inode *inode = &ci->vfs_inode;
		struct ceph_cap *cap;

1915
		spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1916 1917 1918 1919
		cap = ci->i_auth_cap;
		if (cap && cap->session == session) {
			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
			     cap, capsnap);
1920
			__ceph_flush_snaps(ci, &session, 1);
S
Sage Weil 已提交
1921 1922 1923 1924
		} else {
			pr_err("%p auth cap %p not mds%d ???\n", inode,
			       cap, session->s_mds);
		}
1925
		spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941
	}
}

void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
			     struct ceph_mds_session *session)
{
	struct ceph_inode_info *ci;

	kick_flushing_capsnaps(mdsc, session);

	dout("kick_flushing_caps mds%d\n", session->s_mds);
	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
		struct inode *inode = &ci->vfs_inode;
		struct ceph_cap *cap;
		int delayed = 0;

1942
		spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1943 1944 1945 1946 1947 1948 1949 1950 1951 1952
		cap = ci->i_auth_cap;
		if (cap && cap->session == session) {
			dout("kick_flushing_caps %p cap %p %s\n", inode,
			     cap, ceph_cap_string(ci->i_flushing_caps));
			delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
					     __ceph_caps_used(ci),
					     __ceph_caps_wanted(ci),
					     cap->issued | cap->implemented,
					     ci->i_flushing_caps, NULL);
			if (delayed) {
1953
				spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1954
				__cap_delay_requeue(mdsc, ci);
1955
				spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1956 1957 1958 1959
			}
		} else {
			pr_err("%p auth cap %p not mds%d ???\n", inode,
			       cap, session->s_mds);
1960
			spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
1961 1962 1963 1964
		}
	}
}

1965 1966 1967 1968 1969 1970 1971 1972
static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
				     struct ceph_mds_session *session,
				     struct inode *inode)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_cap *cap;
	int delayed = 0;

1973
	spin_lock(&ci->i_ceph_lock);
1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984
	cap = ci->i_auth_cap;
	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
	__ceph_flush_snaps(ci, &session, 1);
	if (ci->i_flushing_caps) {
		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
				     __ceph_caps_used(ci),
				     __ceph_caps_wanted(ci),
				     cap->issued | cap->implemented,
				     ci->i_flushing_caps, NULL);
		if (delayed) {
1985
			spin_lock(&ci->i_ceph_lock);
1986
			__cap_delay_requeue(mdsc, ci);
1987
			spin_unlock(&ci->i_ceph_lock);
1988 1989
		}
	} else {
1990
		spin_unlock(&ci->i_ceph_lock);
1991 1992 1993
	}
}

S
Sage Weil 已提交
1994 1995 1996 1997 1998

/*
 * Take references to capabilities we hold, so that we don't release
 * them to the MDS prematurely.
 *
1999
 * Protected by i_ceph_lock.
S
Sage Weil 已提交
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
 */
static void __take_cap_refs(struct ceph_inode_info *ci, int got)
{
	if (got & CEPH_CAP_PIN)
		ci->i_pin_ref++;
	if (got & CEPH_CAP_FILE_RD)
		ci->i_rd_ref++;
	if (got & CEPH_CAP_FILE_CACHE)
		ci->i_rdcache_ref++;
	if (got & CEPH_CAP_FILE_WR)
		ci->i_wr_ref++;
	if (got & CEPH_CAP_FILE_BUFFER) {
2012
		if (ci->i_wb_ref == 0)
2013
			ihold(&ci->vfs_inode);
2014 2015 2016
		ci->i_wb_ref++;
		dout("__take_cap_refs %p wb %d -> %d (?)\n",
		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
S
Sage Weil 已提交
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032
	}
}

/*
 * Try to grab cap references.  Specify those refs we @want, and the
 * minimal set we @need.  Also include the larger offset we are writing
 * to (when applicable), and check against max_size here as well.
 * Note that caller is responsible for ensuring max_size increases are
 * requested from the MDS.
 */
static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
			    int *got, loff_t endoff, int *check_max, int *err)
{
	struct inode *inode = &ci->vfs_inode;
	int ret = 0;
	int have, implemented;
2033
	int file_wanted;
S
Sage Weil 已提交
2034 2035 2036

	dout("get_cap_refs %p need %s want %s\n", inode,
	     ceph_cap_string(need), ceph_cap_string(want));
2037
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2038

2039 2040 2041 2042 2043
	/* make sure file is actually open */
	file_wanted = __ceph_caps_file_wanted(ci);
	if ((file_wanted & need) == 0) {
		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
		     ceph_cap_string(need), ceph_cap_string(file_wanted));
S
Sage Weil 已提交
2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097
		*err = -EBADF;
		ret = 1;
		goto out;
	}

	if (need & CEPH_CAP_FILE_WR) {
		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
			     inode, endoff, ci->i_max_size);
			if (endoff > ci->i_wanted_max_size) {
				*check_max = 1;
				ret = 1;
			}
			goto out;
		}
		/*
		 * If a sync write is in progress, we must wait, so that we
		 * can get a final snapshot value for size+mtime.
		 */
		if (__ceph_have_pending_cap_snap(ci)) {
			dout("get_cap_refs %p cap_snap_pending\n", inode);
			goto out;
		}
	}
	have = __ceph_caps_issued(ci, &implemented);

	/*
	 * disallow writes while a truncate is pending
	 */
	if (ci->i_truncate_pending)
		have &= ~CEPH_CAP_FILE_WR;

	if ((have & need) == need) {
		/*
		 * Look at (implemented & ~have & not) so that we keep waiting
		 * on transition from wanted -> needed caps.  This is needed
		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
		 * going before a prior buffered writeback happens.
		 */
		int not = want & ~(have & need);
		int revoking = implemented & ~have;
		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
		     inode, ceph_cap_string(have), ceph_cap_string(not),
		     ceph_cap_string(revoking));
		if ((revoking & not) == 0) {
			*got = need | (have & want);
			__take_cap_refs(ci, *got);
			ret = 1;
		}
	} else {
		dout("get_cap_refs %p have %s needed %s\n", inode,
		     ceph_cap_string(have), ceph_cap_string(need));
	}
out:
2098
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114
	dout("get_cap_refs %p ret %d got %s\n", inode,
	     ret, ceph_cap_string(*got));
	return ret;
}

/*
 * Check the offset we are writing up to against our current
 * max_size.  If necessary, tell the MDS we want to write to
 * a larger offset.
 */
static void check_max_size(struct inode *inode, loff_t endoff)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	int check = 0;

	/* do we need to explicitly request a larger max_size? */
2115
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2116 2117 2118 2119 2120 2121 2122 2123
	if ((endoff >= ci->i_max_size ||
	     endoff > (inode->i_size << 1)) &&
	    endoff > ci->i_wanted_max_size) {
		dout("write %p at large endoff %llu, req max_size\n",
		     inode, endoff);
		ci->i_wanted_max_size = endoff;
		check = 1;
	}
2124
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160
	if (check)
		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
}

/*
 * Wait for caps, and take cap references.  If we can't get a WR cap
 * due to a small max_size, make sure we check_max_size (and possibly
 * ask the mds) so we don't get hung up indefinitely.
 */
int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got,
		  loff_t endoff)
{
	int check_max, ret, err;

retry:
	if (endoff > 0)
		check_max_size(&ci->vfs_inode, endoff);
	check_max = 0;
	err = 0;
	ret = wait_event_interruptible(ci->i_cap_wq,
				       try_get_cap_refs(ci, need, want,
							got, endoff,
							&check_max, &err));
	if (err)
		ret = err;
	if (check_max)
		goto retry;
	return ret;
}

/*
 * Take cap refs.  Caller must already know we hold at least one ref
 * on the caps in question or we don't know this is safe.
 */
void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
{
2161
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2162
	__take_cap_refs(ci, caps);
2163
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180
}

/*
 * Release cap refs.
 *
 * If we released the last ref on any given cap, call ceph_check_caps
 * to release (or schedule a release).
 *
 * If we are releasing a WR cap (from a sync write), finalize any affected
 * cap_snap, and wake up any waiters.
 */
void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
{
	struct inode *inode = &ci->vfs_inode;
	int last = 0, put = 0, flushsnaps = 0, wake = 0;
	struct ceph_cap_snap *capsnap;

2181
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2182 2183 2184 2185 2186 2187 2188 2189 2190
	if (had & CEPH_CAP_PIN)
		--ci->i_pin_ref;
	if (had & CEPH_CAP_FILE_RD)
		if (--ci->i_rd_ref == 0)
			last++;
	if (had & CEPH_CAP_FILE_CACHE)
		if (--ci->i_rdcache_ref == 0)
			last++;
	if (had & CEPH_CAP_FILE_BUFFER) {
2191
		if (--ci->i_wb_ref == 0) {
S
Sage Weil 已提交
2192 2193 2194
			last++;
			put++;
		}
2195 2196
		dout("put_cap_refs %p wb %d -> %d (?)\n",
		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
S
Sage Weil 已提交
2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213
	}
	if (had & CEPH_CAP_FILE_WR)
		if (--ci->i_wr_ref == 0) {
			last++;
			if (!list_empty(&ci->i_cap_snaps)) {
				capsnap = list_first_entry(&ci->i_cap_snaps,
						     struct ceph_cap_snap,
						     ci_item);
				if (capsnap->writing) {
					capsnap->writing = 0;
					flushsnaps =
						__ceph_finish_cap_snap(ci,
								       capsnap);
					wake = 1;
				}
			}
		}
2214
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2215

2216 2217
	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
	     last ? " last" : "", put ? " put" : "");
S
Sage Weil 已提交
2218 2219 2220 2221 2222 2223

	if (last && !flushsnaps)
		ceph_check_caps(ci, 0, NULL);
	else if (flushsnaps)
		ceph_flush_snaps(ci);
	if (wake)
2224
		wake_up_all(&ci->i_cap_wq);
S
Sage Weil 已提交
2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240
	if (put)
		iput(inode);
}

/*
 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
 * context.  Adjust per-snap dirty page accounting as appropriate.
 * Once all dirty data for a cap_snap is flushed, flush snapped file
 * metadata back to the MDS.  If we dropped the last ref, call
 * ceph_check_caps.
 */
void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
				struct ceph_snap_context *snapc)
{
	struct inode *inode = &ci->vfs_inode;
	int last = 0;
2241 2242
	int complete_capsnap = 0;
	int drop_capsnap = 0;
S
Sage Weil 已提交
2243 2244 2245
	int found = 0;
	struct ceph_cap_snap *capsnap = NULL;

2246
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2247 2248 2249 2250 2251
	ci->i_wrbuffer_ref -= nr;
	last = !ci->i_wrbuffer_ref;

	if (ci->i_head_snapc == snapc) {
		ci->i_wrbuffer_ref_head -= nr;
2252 2253 2254
		if (ci->i_wrbuffer_ref_head == 0 &&
		    ci->i_dirty_caps == 0 && ci->i_flushing_caps == 0) {
			BUG_ON(!ci->i_head_snapc);
S
Sage Weil 已提交
2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270
			ceph_put_snap_context(ci->i_head_snapc);
			ci->i_head_snapc = NULL;
		}
		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
		     inode,
		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
		     last ? " LAST" : "");
	} else {
		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
			if (capsnap->context == snapc) {
				found = 1;
				break;
			}
		}
		BUG_ON(!found);
2271 2272 2273 2274 2275 2276 2277 2278
		capsnap->dirty_pages -= nr;
		if (capsnap->dirty_pages == 0) {
			complete_capsnap = 1;
			if (capsnap->dirty == 0)
				/* cap writeback completed before we created
				 * the cap_snap; no FLUSHSNAP is needed */
				drop_capsnap = 1;
		}
S
Sage Weil 已提交
2279
		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2280
		     " snap %lld %d/%d -> %d/%d %s%s%s\n",
S
Sage Weil 已提交
2281 2282 2283 2284
		     inode, capsnap, capsnap->context->seq,
		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
		     last ? " (wrbuffer last)" : "",
2285 2286 2287 2288 2289 2290 2291 2292
		     complete_capsnap ? " (complete capsnap)" : "",
		     drop_capsnap ? " (drop capsnap)" : "");
		if (drop_capsnap) {
			ceph_put_snap_context(capsnap->context);
			list_del(&capsnap->ci_item);
			list_del(&capsnap->flushing_item);
			ceph_put_cap_snap(capsnap);
		}
S
Sage Weil 已提交
2293 2294
	}

2295
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2296 2297 2298 2299

	if (last) {
		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
		iput(inode);
2300
	} else if (complete_capsnap) {
S
Sage Weil 已提交
2301
		ceph_flush_snaps(ci);
2302
		wake_up_all(&ci->i_cap_wq);
S
Sage Weil 已提交
2303
	}
2304 2305
	if (drop_capsnap)
		iput(inode);
S
Sage Weil 已提交
2306 2307 2308 2309 2310 2311
}

/*
 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
 * actually be a revocation if it specifies a smaller cap set.)
 *
2312
 * caller holds s_mutex and i_ceph_lock, we drop both.
2313
 *
S
Sage Weil 已提交
2314 2315 2316 2317 2318
 * return value:
 *  0 - ok
 *  1 - check_caps on auth cap only (writeback)
 *  2 - check_caps (ack revoke)
 */
2319 2320 2321 2322
static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
			     struct ceph_mds_session *session,
			     struct ceph_cap *cap,
			     struct ceph_buffer *xattr_buf)
2323
		__releases(ci->i_ceph_lock)
S
Sage Weil 已提交
2324 2325 2326
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	int mds = session->s_mds;
2327
	int seq = le32_to_cpu(grant->seq);
S
Sage Weil 已提交
2328 2329 2330 2331 2332
	int newcaps = le32_to_cpu(grant->caps);
	int issued, implemented, used, wanted, dirty;
	u64 size = le64_to_cpu(grant->size);
	u64 max_size = le64_to_cpu(grant->max_size);
	struct timespec mtime, atime, ctime;
2333
	int check_caps = 0;
S
Sage Weil 已提交
2334 2335 2336
	int wake = 0;
	int writeback = 0;
	int revoked_rdcache = 0;
2337
	int queue_invalidate = 0;
S
Sage Weil 已提交
2338

2339 2340
	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
	     inode, cap, mds, seq, ceph_cap_string(newcaps));
S
Sage Weil 已提交
2341 2342 2343 2344 2345 2346 2347 2348
	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
		inode->i_size);

	/*
	 * If CACHE is being revoked, and we have no dirty buffers,
	 * try to invalidate (once).  (If there are dirty buffers, we
	 * will invalidate _after_ writeback.)
	 */
2349 2350
	if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2351
	    !ci->i_wrbuffer_ref) {
2352 2353 2354
		if (try_nonblocking_invalidate(inode) == 0) {
			revoked_rdcache = 1;
		} else {
S
Sage Weil 已提交
2355 2356 2357
			/* there were locked pages.. invalidate later
			   in a separate thread. */
			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2358
				queue_invalidate = 1;
S
Sage Weil 已提交
2359 2360 2361 2362 2363 2364 2365 2366 2367 2368
				ci->i_rdcache_revoking = ci->i_rdcache_gen;
			}
		}
	}

	/* side effects now are allowed */

	issued = __ceph_caps_issued(ci, &implemented);
	issued |= implemented | __ceph_caps_dirty(ci);

2369
	cap->cap_gen = session->s_cap_gen;
S
Sage Weil 已提交
2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381

	__check_cap_issue(ci, cap, newcaps);

	if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
		inode->i_mode = le32_to_cpu(grant->mode);
		inode->i_uid = le32_to_cpu(grant->uid);
		inode->i_gid = le32_to_cpu(grant->gid);
		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
		     inode->i_uid, inode->i_gid);
	}

	if ((issued & CEPH_CAP_LINK_EXCL) == 0)
M
Miklos Szeredi 已提交
2382
		set_nlink(inode, le32_to_cpu(grant->nlink));
S
Sage Weil 已提交
2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409

	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
		int len = le32_to_cpu(grant->xattr_len);
		u64 version = le64_to_cpu(grant->xattr_version);

		if (version > ci->i_xattrs.version) {
			dout(" got new xattrs v%llu on %p len %d\n",
			     version, inode, len);
			if (ci->i_xattrs.blob)
				ceph_buffer_put(ci->i_xattrs.blob);
			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
			ci->i_xattrs.version = version;
		}
	}

	/* size/ctime/mtime/atime? */
	ceph_fill_file_size(inode, issued,
			    le32_to_cpu(grant->truncate_seq),
			    le64_to_cpu(grant->truncate_size), size);
	ceph_decode_timespec(&mtime, &grant->mtime);
	ceph_decode_timespec(&atime, &grant->atime);
	ceph_decode_timespec(&ctime, &grant->ctime);
	ceph_fill_file_time(inode, issued,
			    le32_to_cpu(grant->time_warp_seq), &ctime, &mtime,
			    &atime);

	/* max size increase? */
2410
	if (ci->i_auth_cap == cap && max_size != ci->i_max_size) {
S
Sage Weil 已提交
2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441
		dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
		ci->i_max_size = max_size;
		if (max_size >= ci->i_wanted_max_size) {
			ci->i_wanted_max_size = 0;  /* reset */
			ci->i_requested_max_size = 0;
		}
		wake = 1;
	}

	/* check cap bits */
	wanted = __ceph_caps_wanted(ci);
	used = __ceph_caps_used(ci);
	dirty = __ceph_caps_dirty(ci);
	dout(" my wanted = %s, used = %s, dirty %s\n",
	     ceph_cap_string(wanted),
	     ceph_cap_string(used),
	     ceph_cap_string(dirty));
	if (wanted != le32_to_cpu(grant->wanted)) {
		dout("mds wanted %s -> %s\n",
		     ceph_cap_string(le32_to_cpu(grant->wanted)),
		     ceph_cap_string(wanted));
		grant->wanted = cpu_to_le32(wanted);
	}

	cap->seq = seq;

	/* file layout may have changed */
	ci->i_layout = grant->layout;

	/* revocation, grant, or no-op? */
	if (cap->issued & ~newcaps) {
2442 2443 2444 2445 2446 2447
		int revoking = cap->issued & ~newcaps;

		dout("revocation: %s -> %s (revoking %s)\n",
		     ceph_cap_string(cap->issued),
		     ceph_cap_string(newcaps),
		     ceph_cap_string(revoking));
2448
		if (revoking & used & CEPH_CAP_FILE_BUFFER)
2449 2450 2451 2452 2453 2454 2455 2456 2457
			writeback = 1;  /* initiate writeback; will delay ack */
		else if (revoking == CEPH_CAP_FILE_CACHE &&
			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
			 queue_invalidate)
			; /* do nothing yet, invalidation will be queued */
		else if (cap == ci->i_auth_cap)
			check_caps = 1; /* check auth cap only */
		else
			check_caps = 2; /* check all caps */
S
Sage Weil 已提交
2458
		cap->issued = newcaps;
2459
		cap->implemented |= newcaps;
S
Sage Weil 已提交
2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471
	} else if (cap->issued == newcaps) {
		dout("caps unchanged: %s -> %s\n",
		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
	} else {
		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
		     ceph_cap_string(newcaps));
		cap->issued = newcaps;
		cap->implemented |= newcaps; /* add bits only, to
					      * avoid stepping on a
					      * pending revocation */
		wake = 1;
	}
2472
	BUG_ON(cap->issued & ~cap->implemented);
S
Sage Weil 已提交
2473

2474
	spin_unlock(&ci->i_ceph_lock);
2475
	if (writeback)
S
Sage Weil 已提交
2476 2477 2478 2479 2480
		/*
		 * queue inode for writeback: we can't actually call
		 * filemap_write_and_wait, etc. from message handler
		 * context.
		 */
2481 2482 2483
		ceph_queue_writeback(inode);
	if (queue_invalidate)
		ceph_queue_invalidate(inode);
S
Sage Weil 已提交
2484
	if (wake)
2485
		wake_up_all(&ci->i_cap_wq);
2486 2487 2488 2489 2490 2491 2492 2493

	if (check_caps == 1)
		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
				session);
	else if (check_caps == 2)
		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
	else
		mutex_unlock(&session->s_mutex);
S
Sage Weil 已提交
2494 2495 2496 2497 2498 2499
}

/*
 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
 * MDS has been safely committed.
 */
2500
static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
S
Sage Weil 已提交
2501 2502 2503
				 struct ceph_mds_caps *m,
				 struct ceph_mds_session *session,
				 struct ceph_cap *cap)
2504
	__releases(ci->i_ceph_lock)
S
Sage Weil 已提交
2505 2506
{
	struct ceph_inode_info *ci = ceph_inode(inode);
2507
	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
S
Sage Weil 已提交
2508 2509 2510
	unsigned seq = le32_to_cpu(m->seq);
	int dirty = le32_to_cpu(m->dirty);
	int cleaned = 0;
2511
	int drop = 0;
S
Sage Weil 已提交
2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539
	int i;

	for (i = 0; i < CEPH_CAP_BITS; i++)
		if ((dirty & (1 << i)) &&
		    flush_tid == ci->i_cap_flush_tid[i])
			cleaned |= 1 << i;

	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
	     " flushing %s -> %s\n",
	     inode, session->s_mds, seq, ceph_cap_string(dirty),
	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));

	if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
		goto out;

	ci->i_flushing_caps &= ~cleaned;

	spin_lock(&mdsc->cap_dirty_lock);
	if (ci->i_flushing_caps == 0) {
		list_del_init(&ci->i_flushing_item);
		if (!list_empty(&session->s_cap_flushing))
			dout(" mds%d still flushing cap on %p\n",
			     session->s_mds,
			     &list_entry(session->s_cap_flushing.next,
					 struct ceph_inode_info,
					 i_flushing_item)->vfs_inode);
		mdsc->num_cap_flushing--;
2540
		wake_up_all(&mdsc->cap_flushing_wq);
S
Sage Weil 已提交
2541
		dout(" inode %p now !flushing\n", inode);
2542 2543 2544 2545 2546

		if (ci->i_dirty_caps == 0) {
			dout(" inode %p now clean\n", inode);
			BUG_ON(!list_empty(&ci->i_dirty_item));
			drop = 1;
2547 2548 2549 2550 2551
			if (ci->i_wrbuffer_ref_head == 0) {
				BUG_ON(!ci->i_head_snapc);
				ceph_put_snap_context(ci->i_head_snapc);
				ci->i_head_snapc = NULL;
			}
S
Sage Weil 已提交
2552 2553
		} else {
			BUG_ON(list_empty(&ci->i_dirty_item));
2554
		}
S
Sage Weil 已提交
2555 2556
	}
	spin_unlock(&mdsc->cap_dirty_lock);
2557
	wake_up_all(&ci->i_cap_wq);
S
Sage Weil 已提交
2558 2559

out:
2560
	spin_unlock(&ci->i_ceph_lock);
2561
	if (drop)
S
Sage Weil 已提交
2562 2563 2564 2565 2566 2567 2568 2569 2570
		iput(inode);
}

/*
 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
 * throw away our cap_snap.
 *
 * Caller hold s_mutex.
 */
2571
static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
S
Sage Weil 已提交
2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582
				     struct ceph_mds_caps *m,
				     struct ceph_mds_session *session)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	u64 follows = le64_to_cpu(m->snap_follows);
	struct ceph_cap_snap *capsnap;
	int drop = 0;

	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
	     inode, ci, session->s_mds, follows);

2583
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2584 2585 2586 2587 2588 2589 2590 2591 2592
	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
		if (capsnap->follows == follows) {
			if (capsnap->flush_tid != flush_tid) {
				dout(" cap_snap %p follows %lld tid %lld !="
				     " %lld\n", capsnap, follows,
				     flush_tid, capsnap->flush_tid);
				break;
			}
			WARN_ON(capsnap->dirty_pages || capsnap->writing);
2593 2594
			dout(" removing %p cap_snap %p follows %lld\n",
			     inode, capsnap, follows);
S
Sage Weil 已提交
2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605
			ceph_put_snap_context(capsnap->context);
			list_del(&capsnap->ci_item);
			list_del(&capsnap->flushing_item);
			ceph_put_cap_snap(capsnap);
			drop = 1;
			break;
		} else {
			dout(" skipping cap_snap %p follows %lld\n",
			     capsnap, capsnap->follows);
		}
	}
2606
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618
	if (drop)
		iput(inode);
}

/*
 * Handle TRUNC from MDS, indicating file truncation.
 *
 * caller hold s_mutex.
 */
static void handle_cap_trunc(struct inode *inode,
			     struct ceph_mds_caps *trunc,
			     struct ceph_mds_session *session)
2619
	__releases(ci->i_ceph_lock)
S
Sage Weil 已提交
2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	int mds = session->s_mds;
	int seq = le32_to_cpu(trunc->seq);
	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
	u64 size = le64_to_cpu(trunc->size);
	int implemented = 0;
	int dirty = __ceph_caps_dirty(ci);
	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
	int queue_trunc = 0;

	issued |= implemented | dirty;

	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
	     inode, mds, seq, truncate_size, truncate_seq);
	queue_trunc = ceph_fill_file_size(inode, issued,
					  truncate_seq, truncate_size, size);
2638
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2639 2640

	if (queue_trunc)
2641
		ceph_queue_vmtruncate(inode);
S
Sage Weil 已提交
2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652
}

/*
 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
 * different one.  If we are the most recent migration we've seen (as
 * indicated by mseq), make note of the migrating cap bits for the
 * duration (until we see the corresponding IMPORT).
 *
 * caller holds s_mutex
 */
static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
2653 2654
			      struct ceph_mds_session *session,
			      int *open_target_sessions)
S
Sage Weil 已提交
2655
{
S
Sage Weil 已提交
2656
	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
S
Sage Weil 已提交
2657 2658 2659 2660 2661 2662 2663 2664 2665 2666
	struct ceph_inode_info *ci = ceph_inode(inode);
	int mds = session->s_mds;
	unsigned mseq = le32_to_cpu(ex->migrate_seq);
	struct ceph_cap *cap = NULL, *t;
	struct rb_node *p;
	int remember = 1;

	dout("handle_cap_export inode %p ci %p mds%d mseq %d\n",
	     inode, ci, mds, mseq);

2667
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686

	/* make sure we haven't seen a higher mseq */
	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
		t = rb_entry(p, struct ceph_cap, ci_node);
		if (ceph_seq_cmp(t->mseq, mseq) > 0) {
			dout(" higher mseq on cap from mds%d\n",
			     t->session->s_mds);
			remember = 0;
		}
		if (t->session->s_mds == mds)
			cap = t;
	}

	if (cap) {
		if (remember) {
			/* make note */
			ci->i_cap_exporting_mds = mds;
			ci->i_cap_exporting_mseq = mseq;
			ci->i_cap_exporting_issued = cap->issued;
2687 2688 2689 2690 2691 2692

			/*
			 * make sure we have open sessions with all possible
			 * export targets, so that we get the matching IMPORT
			 */
			*open_target_sessions = 1;
S
Sage Weil 已提交
2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705

			/*
			 * we can't flush dirty caps that we've seen the
			 * EXPORT but no IMPORT for
			 */
			spin_lock(&mdsc->cap_dirty_lock);
			if (!list_empty(&ci->i_dirty_item)) {
				dout(" moving %p to cap_dirty_migrating\n",
				     inode);
				list_move(&ci->i_dirty_item,
					  &mdsc->cap_dirty_migrating);
			}
			spin_unlock(&mdsc->cap_dirty_lock);
S
Sage Weil 已提交
2706
		}
S
Sage Weil 已提交
2707
		__ceph_remove_cap(cap);
S
Sage Weil 已提交
2708
	}
2709
	/* else, we already released it */
S
Sage Weil 已提交
2710

2711
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742
}

/*
 * Handle cap IMPORT.  If there are temp bits from an older EXPORT,
 * clean them up.
 *
 * caller holds s_mutex.
 */
static void handle_cap_import(struct ceph_mds_client *mdsc,
			      struct inode *inode, struct ceph_mds_caps *im,
			      struct ceph_mds_session *session,
			      void *snaptrace, int snaptrace_len)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	int mds = session->s_mds;
	unsigned issued = le32_to_cpu(im->caps);
	unsigned wanted = le32_to_cpu(im->wanted);
	unsigned seq = le32_to_cpu(im->seq);
	unsigned mseq = le32_to_cpu(im->migrate_seq);
	u64 realmino = le64_to_cpu(im->realm);
	u64 cap_id = le64_to_cpu(im->cap_id);

	if (ci->i_cap_exporting_mds >= 0 &&
	    ceph_seq_cmp(ci->i_cap_exporting_mseq, mseq) < 0) {
		dout("handle_cap_import inode %p ci %p mds%d mseq %d"
		     " - cleared exporting from mds%d\n",
		     inode, ci, mds, mseq,
		     ci->i_cap_exporting_mds);
		ci->i_cap_exporting_issued = 0;
		ci->i_cap_exporting_mseq = 0;
		ci->i_cap_exporting_mds = -1;
S
Sage Weil 已提交
2743 2744 2745 2746 2747 2748 2749

		spin_lock(&mdsc->cap_dirty_lock);
		if (!list_empty(&ci->i_dirty_item)) {
			dout(" moving %p back to cap_dirty\n", inode);
			list_move(&ci->i_dirty_item, &mdsc->cap_dirty);
		}
		spin_unlock(&mdsc->cap_dirty_lock);
S
Sage Weil 已提交
2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
	} else {
		dout("handle_cap_import inode %p ci %p mds%d mseq %d\n",
		     inode, ci, mds, mseq);
	}

	down_write(&mdsc->snap_rwsem);
	ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
			       false);
	downgrade_write(&mdsc->snap_rwsem);
	ceph_add_cap(inode, session, cap_id, -1,
		     issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
		     NULL /* no caps context */);
2762
	kick_flushing_inode_caps(mdsc, session, inode);
S
Sage Weil 已提交
2763
	up_read(&mdsc->snap_rwsem);
2764 2765

	/* make sure we re-request max_size, if necessary */
2766
	spin_lock(&ci->i_ceph_lock);
2767
	ci->i_wanted_max_size = 0;  /* reset */
2768
	ci->i_requested_max_size = 0;
2769
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781
}

/*
 * Handle a caps message from the MDS.
 *
 * Identify the appropriate session, inode, and call the right handler
 * based on the cap op.
 */
void ceph_handle_caps(struct ceph_mds_session *session,
		      struct ceph_msg *msg)
{
	struct ceph_mds_client *mdsc = session->s_mdsc;
2782
	struct super_block *sb = mdsc->fsc->sb;
S
Sage Weil 已提交
2783
	struct inode *inode;
2784
	struct ceph_inode_info *ci;
S
Sage Weil 已提交
2785 2786
	struct ceph_cap *cap;
	struct ceph_mds_caps *h;
2787
	int mds = session->s_mds;
S
Sage Weil 已提交
2788
	int op;
2789
	u32 seq, mseq;
S
Sage Weil 已提交
2790 2791 2792
	struct ceph_vino vino;
	u64 cap_id;
	u64 size, max_size;
2793
	u64 tid;
2794
	void *snaptrace;
2795 2796 2797
	size_t snaptrace_len;
	void *flock;
	u32 flock_len;
2798
	int open_target_sessions = 0;
S
Sage Weil 已提交
2799 2800 2801 2802

	dout("handle_caps from mds%d\n", mds);

	/* decode */
2803
	tid = le64_to_cpu(msg->hdr.tid);
S
Sage Weil 已提交
2804 2805 2806 2807 2808 2809 2810 2811
	if (msg->front.iov_len < sizeof(*h))
		goto bad;
	h = msg->front.iov_base;
	op = le32_to_cpu(h->op);
	vino.ino = le64_to_cpu(h->ino);
	vino.snap = CEPH_NOSNAP;
	cap_id = le64_to_cpu(h->cap_id);
	seq = le32_to_cpu(h->seq);
2812
	mseq = le32_to_cpu(h->migrate_seq);
S
Sage Weil 已提交
2813 2814 2815
	size = le64_to_cpu(h->size);
	max_size = le64_to_cpu(h->max_size);

2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830
	snaptrace = h + 1;
	snaptrace_len = le32_to_cpu(h->snap_trace_len);

	if (le16_to_cpu(msg->hdr.version) >= 2) {
		void *p, *end;

		p = snaptrace + snaptrace_len;
		end = msg->front.iov_base + msg->front.iov_len;
		ceph_decode_32_safe(&p, end, flock_len, bad);
		flock = p;
	} else {
		flock = NULL;
		flock_len = 0;
	}

S
Sage Weil 已提交
2831 2832 2833 2834 2835
	mutex_lock(&session->s_mutex);
	session->s_seq++;
	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
	     (unsigned)seq);

2836 2837 2838
	if (op == CEPH_CAP_OP_IMPORT)
		ceph_add_cap_releases(mdsc, session);

S
Sage Weil 已提交
2839 2840
	/* lookup ino */
	inode = ceph_find_inode(sb, vino);
2841
	ci = ceph_inode(inode);
S
Sage Weil 已提交
2842 2843 2844 2845
	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
	     vino.snap, inode);
	if (!inode) {
		dout(" i don't have ino %llx\n", vino.ino);
2846 2847 2848 2849

		if (op == CEPH_CAP_OP_IMPORT)
			__queue_cap_release(session, vino.ino, cap_id,
					    mseq, seq);
2850
		goto flush_cap_releases;
S
Sage Weil 已提交
2851 2852 2853 2854 2855
	}

	/* these will work even if we don't have a cap yet */
	switch (op) {
	case CEPH_CAP_OP_FLUSHSNAP_ACK:
2856
		handle_cap_flushsnap_ack(inode, tid, h, session);
S
Sage Weil 已提交
2857 2858 2859
		goto done;

	case CEPH_CAP_OP_EXPORT:
2860
		handle_cap_export(inode, h, session, &open_target_sessions);
S
Sage Weil 已提交
2861 2862 2863 2864
		goto done;

	case CEPH_CAP_OP_IMPORT:
		handle_cap_import(mdsc, inode, h, session,
2865
				  snaptrace, snaptrace_len);
S
Sage Weil 已提交
2866 2867 2868
	}

	/* the rest require a cap */
2869
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2870 2871
	cap = __get_cap_for_mds(ceph_inode(inode), mds);
	if (!cap) {
2872
		dout(" no cap on %p ino %llx.%llx from mds%d\n",
S
Sage Weil 已提交
2873
		     inode, ceph_ino(inode), ceph_snap(inode), mds);
2874
		spin_unlock(&ci->i_ceph_lock);
2875
		goto flush_cap_releases;
S
Sage Weil 已提交
2876 2877
	}

2878
	/* note that each of these drops i_ceph_lock for us */
S
Sage Weil 已提交
2879 2880 2881
	switch (op) {
	case CEPH_CAP_OP_REVOKE:
	case CEPH_CAP_OP_GRANT:
2882
	case CEPH_CAP_OP_IMPORT:
2883 2884
		handle_cap_grant(inode, h, session, cap, msg->middle);
		goto done_unlocked;
S
Sage Weil 已提交
2885 2886

	case CEPH_CAP_OP_FLUSH_ACK:
2887
		handle_cap_flush_ack(inode, tid, h, session, cap);
S
Sage Weil 已提交
2888 2889 2890 2891 2892 2893 2894
		break;

	case CEPH_CAP_OP_TRUNC:
		handle_cap_trunc(inode, h, session);
		break;

	default:
2895
		spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2896 2897 2898 2899
		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
		       ceph_cap_op_name(op));
	}

2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910
	goto done;

flush_cap_releases:
	/*
	 * send any full release message to try to move things
	 * along for the mds (who clearly thinks we still have this
	 * cap).
	 */
	ceph_add_cap_releases(mdsc, session);
	ceph_send_cap_releases(mdsc, session);

S
Sage Weil 已提交
2911
done:
2912 2913
	mutex_unlock(&session->s_mutex);
done_unlocked:
S
Sage Weil 已提交
2914 2915
	if (inode)
		iput(inode);
2916 2917
	if (open_target_sessions)
		ceph_mdsc_open_export_target_sessions(mdsc, session);
S
Sage Weil 已提交
2918 2919 2920 2921
	return;

bad:
	pr_err("ceph_handle_caps: corrupt message\n");
2922
	ceph_msg_dump(msg);
S
Sage Weil 已提交
2923 2924 2925 2926 2927 2928
	return;
}

/*
 * Delayed work handler to process end of delayed cap release LRU list.
 */
2929
void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
S
Sage Weil 已提交
2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952
{
	struct ceph_inode_info *ci;
	int flags = CHECK_CAPS_NODELAY;

	dout("check_delayed_caps\n");
	while (1) {
		spin_lock(&mdsc->cap_delay_lock);
		if (list_empty(&mdsc->cap_delay_list))
			break;
		ci = list_first_entry(&mdsc->cap_delay_list,
				      struct ceph_inode_info,
				      i_cap_delay_list);
		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
		    time_before(jiffies, ci->i_hold_caps_max))
			break;
		list_del_init(&ci->i_cap_delay_list);
		spin_unlock(&mdsc->cap_delay_lock);
		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
		ceph_check_caps(ci, flags, NULL);
	}
	spin_unlock(&mdsc->cap_delay_lock);
}

2953 2954 2955 2956 2957
/*
 * Flush all dirty caps to the mds
 */
void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
{
S
Sage Weil 已提交
2958 2959
	struct ceph_inode_info *ci;
	struct inode *inode;
2960 2961 2962

	dout("flush_dirty_caps\n");
	spin_lock(&mdsc->cap_dirty_lock);
S
Sage Weil 已提交
2963 2964 2965
	while (!list_empty(&mdsc->cap_dirty)) {
		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
				      i_dirty_item);
2966 2967
		inode = &ci->vfs_inode;
		ihold(inode);
S
Sage Weil 已提交
2968
		dout("flush_dirty_caps %p\n", inode);
2969
		spin_unlock(&mdsc->cap_dirty_lock);
2970 2971
		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
		iput(inode);
2972 2973 2974
		spin_lock(&mdsc->cap_dirty_lock);
	}
	spin_unlock(&mdsc->cap_dirty_lock);
S
Sage Weil 已提交
2975
	dout("flush_dirty_caps done\n");
2976 2977
}

S
Sage Weil 已提交
2978 2979 2980 2981 2982 2983 2984 2985 2986 2987
/*
 * Drop open file reference.  If we were the last open file,
 * we may need to release capabilities to the MDS (or schedule
 * their delayed release).
 */
void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
{
	struct inode *inode = &ci->vfs_inode;
	int last = 0;

2988
	spin_lock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2989 2990 2991 2992 2993
	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
	if (--ci->i_nr_by_mode[fmode] == 0)
		last++;
2994
	spin_unlock(&ci->i_ceph_lock);
S
Sage Weil 已提交
2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013

	if (last && ci->i_vino.snap == CEPH_NOSNAP)
		ceph_check_caps(ci, 0, NULL);
}

/*
 * Helpers for embedding cap and dentry lease releases into mds
 * requests.
 *
 * @force is used by dentry_release (below) to force inclusion of a
 * record for the directory inode, even when there aren't any caps to
 * drop.
 */
int ceph_encode_inode_release(void **p, struct inode *inode,
			      int mds, int drop, int unless, int force)
{
	struct ceph_inode_info *ci = ceph_inode(inode);
	struct ceph_cap *cap;
	struct ceph_mds_request_release *rel = *p;
3014
	int used, dirty;
S
Sage Weil 已提交
3015 3016
	int ret = 0;

3017
	spin_lock(&ci->i_ceph_lock);
3018
	used = __ceph_caps_used(ci);
3019
	dirty = __ceph_caps_dirty(ci);
3020

3021 3022
	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3023 3024
	     ceph_cap_string(unless));

3025 3026
	/* only drop unused, clean caps */
	drop &= ~(used | dirty);
3027

S
Sage Weil 已提交
3028 3029 3030 3031 3032 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 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071
	cap = __get_cap_for_mds(ci, mds);
	if (cap && __cap_is_valid(cap)) {
		if (force ||
		    ((cap->issued & drop) &&
		     (cap->issued & unless) == 0)) {
			if ((cap->issued & drop) &&
			    (cap->issued & unless) == 0) {
				dout("encode_inode_release %p cap %p %s -> "
				     "%s\n", inode, cap,
				     ceph_cap_string(cap->issued),
				     ceph_cap_string(cap->issued & ~drop));
				cap->issued &= ~drop;
				cap->implemented &= ~drop;
				if (ci->i_ceph_flags & CEPH_I_NODELAY) {
					int wanted = __ceph_caps_wanted(ci);
					dout("  wanted %s -> %s (act %s)\n",
					     ceph_cap_string(cap->mds_wanted),
					     ceph_cap_string(cap->mds_wanted &
							     ~wanted),
					     ceph_cap_string(wanted));
					cap->mds_wanted &= wanted;
				}
			} else {
				dout("encode_inode_release %p cap %p %s"
				     " (force)\n", inode, cap,
				     ceph_cap_string(cap->issued));
			}

			rel->ino = cpu_to_le64(ceph_ino(inode));
			rel->cap_id = cpu_to_le64(cap->cap_id);
			rel->seq = cpu_to_le32(cap->seq);
			rel->issue_seq = cpu_to_le32(cap->issue_seq),
			rel->mseq = cpu_to_le32(cap->mseq);
			rel->caps = cpu_to_le32(cap->issued);
			rel->wanted = cpu_to_le32(cap->mds_wanted);
			rel->dname_len = 0;
			rel->dname_seq = 0;
			*p += sizeof(*rel);
			ret = 1;
		} else {
			dout("encode_inode_release %p cap %p %s\n",
			     inode, cap, ceph_cap_string(cap->issued));
		}
	}
3072
	spin_unlock(&ci->i_ceph_lock);
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	return ret;
}

int ceph_encode_dentry_release(void **p, struct dentry *dentry,
			       int mds, int drop, int unless)
{
	struct inode *dir = dentry->d_parent->d_inode;
	struct ceph_mds_request_release *rel = *p;
	struct ceph_dentry_info *di = ceph_dentry(dentry);
	int force = 0;
	int ret;

	/*
	 * force an record for the directory caps if we have a dentry lease.
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	 * this is racy (can't take i_ceph_lock and d_lock together), but it
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	 * doesn't have to be perfect; the mds will revoke anything we don't
	 * release.
	 */
	spin_lock(&dentry->d_lock);
	if (di->lease_session && di->lease_session->s_mds == mds)
		force = 1;
	spin_unlock(&dentry->d_lock);

	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);

	spin_lock(&dentry->d_lock);
	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
		dout("encode_dentry_release %p mds%d seq %d\n",
		     dentry, mds, (int)di->lease_seq);
		rel->dname_len = cpu_to_le32(dentry->d_name.len);
		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
		*p += dentry->d_name.len;
		rel->dname_seq = cpu_to_le32(di->lease_seq);
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		__ceph_mdsc_drop_dentry_lease(dentry);
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	}
	spin_unlock(&dentry->d_lock);
	return ret;
}