pnfs.c 42.7 KB
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/*
 *  pNFS functions to call and manage layout drivers.
 *
 *  Copyright (c) 2002 [year of first publication]
 *  The Regents of the University of Michigan
 *  All Rights Reserved
 *
 *  Dean Hildebrand <dhildebz@umich.edu>
 *
 *  Permission is granted to use, copy, create derivative works, and
 *  redistribute this software and such derivative works for any purpose,
 *  so long as the name of the University of Michigan is not used in
 *  any advertising or publicity pertaining to the use or distribution
 *  of this software without specific, written prior authorization. If
 *  the above copyright notice or any other identification of the
 *  University of Michigan is included in any copy of any portion of
 *  this software, then the disclaimer below must also be included.
 *
 *  This software is provided as is, without representation or warranty
 *  of any kind either express or implied, including without limitation
 *  the implied warranties of merchantability, fitness for a particular
 *  purpose, or noninfringement.  The Regents of the University of
 *  Michigan shall not be liable for any damages, including special,
 *  indirect, incidental, or consequential damages, with respect to any
 *  claim arising out of or in connection with the use of the software,
 *  even if it has been or is hereafter advised of the possibility of
 *  such damages.
 */

#include <linux/nfs_fs.h>
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#include <linux/nfs_page.h>
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#include <linux/module.h>
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#include "internal.h"
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#include "pnfs.h"
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#include "iostat.h"
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#define NFSDBG_FACILITY		NFSDBG_PNFS

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/* Locking:
 *
 * pnfs_spinlock:
 *      protects pnfs_modules_tbl.
 */
static DEFINE_SPINLOCK(pnfs_spinlock);

/*
 * pnfs_modules_tbl holds all pnfs modules
 */
static LIST_HEAD(pnfs_modules_tbl);

/* Return the registered pnfs layout driver module matching given id */
static struct pnfs_layoutdriver_type *
find_pnfs_driver_locked(u32 id)
{
	struct pnfs_layoutdriver_type *local;

	list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
		if (local->id == id)
			goto out;
	local = NULL;
out:
	dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
	return local;
}

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static struct pnfs_layoutdriver_type *
find_pnfs_driver(u32 id)
{
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	struct pnfs_layoutdriver_type *local;

	spin_lock(&pnfs_spinlock);
	local = find_pnfs_driver_locked(id);
	spin_unlock(&pnfs_spinlock);
	return local;
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}

void
unset_pnfs_layoutdriver(struct nfs_server *nfss)
{
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	if (nfss->pnfs_curr_ld) {
		if (nfss->pnfs_curr_ld->clear_layoutdriver)
			nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
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		module_put(nfss->pnfs_curr_ld->owner);
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	}
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	nfss->pnfs_curr_ld = NULL;
}

/*
 * Try to set the server's pnfs module to the pnfs layout type specified by id.
 * Currently only one pNFS layout driver per filesystem is supported.
 *
 * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
 */
void
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set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
		      u32 id)
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{
	struct pnfs_layoutdriver_type *ld_type = NULL;

	if (id == 0)
		goto out_no_driver;
	if (!(server->nfs_client->cl_exchange_flags &
		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
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		printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
			__func__, id, server->nfs_client->cl_exchange_flags);
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		goto out_no_driver;
	}
	ld_type = find_pnfs_driver(id);
	if (!ld_type) {
		request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
		ld_type = find_pnfs_driver(id);
		if (!ld_type) {
			dprintk("%s: No pNFS module found for %u.\n",
				__func__, id);
			goto out_no_driver;
		}
	}
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	if (!try_module_get(ld_type->owner)) {
		dprintk("%s: Could not grab reference on module\n", __func__);
		goto out_no_driver;
	}
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	server->pnfs_curr_ld = ld_type;
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	if (ld_type->set_layoutdriver
	    && ld_type->set_layoutdriver(server, mntfh)) {
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		printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
			"driver %u.\n", __func__, id);
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		module_put(ld_type->owner);
		goto out_no_driver;
	}
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	dprintk("%s: pNFS module for %u set\n", __func__, id);
	return;

out_no_driver:
	dprintk("%s: Using NFSv4 I/O\n", __func__);
	server->pnfs_curr_ld = NULL;
}
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int
pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
{
	int status = -EINVAL;
	struct pnfs_layoutdriver_type *tmp;

	if (ld_type->id == 0) {
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		printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
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		return status;
	}
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	if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
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		printk(KERN_ERR "NFS: %s Layout driver must provide "
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		       "alloc_lseg and free_lseg.\n", __func__);
		return status;
	}
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	spin_lock(&pnfs_spinlock);
	tmp = find_pnfs_driver_locked(ld_type->id);
	if (!tmp) {
		list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
		status = 0;
		dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
			ld_type->name);
	} else {
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		printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
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			__func__, ld_type->id);
	}
	spin_unlock(&pnfs_spinlock);

	return status;
}
EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);

void
pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
{
	dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
	spin_lock(&pnfs_spinlock);
	list_del(&ld_type->pnfs_tblid);
	spin_unlock(&pnfs_spinlock);
}
EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
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/*
 * pNFS client layout cache
 */

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/* Need to hold i_lock if caller does not already hold reference */
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void
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get_layout_hdr(struct pnfs_layout_hdr *lo)
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{
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	atomic_inc(&lo->plh_refcount);
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}

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static struct pnfs_layout_hdr *
pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
{
	struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
	return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) :
		kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags);
}

static void
pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
{
	struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld;
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	put_rpccred(lo->plh_lc_cred);
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	return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo);
}

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static void
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destroy_layout_hdr(struct pnfs_layout_hdr *lo)
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{
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	dprintk("%s: freeing layout cache %p\n", __func__, lo);
	BUG_ON(!list_empty(&lo->plh_layouts));
	NFS_I(lo->plh_inode)->layout = NULL;
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	pnfs_free_layout_hdr(lo);
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}
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static void
put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
{
	if (atomic_dec_and_test(&lo->plh_refcount))
		destroy_layout_hdr(lo);
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}

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void
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put_layout_hdr(struct pnfs_layout_hdr *lo)
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{
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	struct inode *inode = lo->plh_inode;

	if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
		destroy_layout_hdr(lo);
		spin_unlock(&inode->i_lock);
	}
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}

static void
init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
{
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	INIT_LIST_HEAD(&lseg->pls_list);
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	INIT_LIST_HEAD(&lseg->pls_lc_list);
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	atomic_set(&lseg->pls_refcount, 1);
	smp_mb();
	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
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	lseg->pls_layout = lo;
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}

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static void free_lseg(struct pnfs_layout_segment *lseg)
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{
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	struct inode *ino = lseg->pls_layout->plh_inode;
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	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
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	/* Matched by get_layout_hdr in pnfs_insert_layout */
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	put_layout_hdr(NFS_I(ino)->layout);
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}

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static void
put_lseg_common(struct pnfs_layout_segment *lseg)
{
	struct inode *inode = lseg->pls_layout->plh_inode;

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	WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
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	list_del_init(&lseg->pls_list);
	if (list_empty(&lseg->pls_layout->plh_segs)) {
		set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);
		/* Matched by initial refcount set in alloc_init_layout_hdr */
		put_layout_hdr_locked(lseg->pls_layout);
	}
	rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
}

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void
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put_lseg(struct pnfs_layout_segment *lseg)
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{
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	struct inode *inode;

	if (!lseg)
		return;

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	dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
		atomic_read(&lseg->pls_refcount),
		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
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	inode = lseg->pls_layout->plh_inode;
	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
		LIST_HEAD(free_me);
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		put_lseg_common(lseg);
		list_add(&lseg->pls_list, &free_me);
		spin_unlock(&inode->i_lock);
		pnfs_free_lseg_list(&free_me);
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	}
}
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EXPORT_SYMBOL_GPL(put_lseg);
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static inline u64
end_offset(u64 start, u64 len)
{
	u64 end;

	end = start + len;
	return end >= start ? end : NFS4_MAX_UINT64;
}

/* last octet in a range */
static inline u64
last_byte_offset(u64 start, u64 len)
{
	u64 end;

	BUG_ON(!len);
	end = start + len;
	return end > start ? end - 1 : NFS4_MAX_UINT64;
}

/*
 * is l2 fully contained in l1?
 *   start1                             end1
 *   [----------------------------------)
 *           start2           end2
 *           [----------------)
 */
static inline int
lo_seg_contained(struct pnfs_layout_range *l1,
		 struct pnfs_layout_range *l2)
{
	u64 start1 = l1->offset;
	u64 end1 = end_offset(start1, l1->length);
	u64 start2 = l2->offset;
	u64 end2 = end_offset(start2, l2->length);

	return (start1 <= start2) && (end1 >= end2);
}

/*
 * is l1 and l2 intersecting?
 *   start1                             end1
 *   [----------------------------------)
 *                              start2           end2
 *                              [----------------)
 */
static inline int
lo_seg_intersecting(struct pnfs_layout_range *l1,
		    struct pnfs_layout_range *l2)
{
	u64 start1 = l1->offset;
	u64 end1 = end_offset(start1, l1->length);
	u64 start2 = l2->offset;
	u64 end2 = end_offset(start2, l2->length);

	return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
	       (end2 == NFS4_MAX_UINT64 || end2 > start1);
}

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static bool
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should_free_lseg(struct pnfs_layout_range *lseg_range,
		 struct pnfs_layout_range *recall_range)
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{
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	return (recall_range->iomode == IOMODE_ANY ||
		lseg_range->iomode == recall_range->iomode) &&
	       lo_seg_intersecting(lseg_range, recall_range);
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}

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/* Returns 1 if lseg is removed from list, 0 otherwise */
static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
			     struct list_head *tmp_list)
{
	int rv = 0;

	if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
		/* Remove the reference keeping the lseg in the
		 * list.  It will now be removed when all
		 * outstanding io is finished.
		 */
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		dprintk("%s: lseg %p ref %d\n", __func__, lseg,
			atomic_read(&lseg->pls_refcount));
		if (atomic_dec_and_test(&lseg->pls_refcount)) {
			put_lseg_common(lseg);
			list_add(&lseg->pls_list, tmp_list);
			rv = 1;
		}
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	}
	return rv;
}

/* Returns count of number of matching invalid lsegs remaining in list
 * after call.
 */
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int
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mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
			    struct list_head *tmp_list,
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			    struct pnfs_layout_range *recall_range)
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{
	struct pnfs_layout_segment *lseg, *next;
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	int invalid = 0, removed = 0;
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	dprintk("%s:Begin lo %p\n", __func__, lo);

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	if (list_empty(&lo->plh_segs)) {
		if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
			put_layout_hdr_locked(lo);
		return 0;
	}
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	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
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		if (!recall_range ||
		    should_free_lseg(&lseg->pls_range, recall_range)) {
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			dprintk("%s: freeing lseg %p iomode %d "
				"offset %llu length %llu\n", __func__,
				lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
				lseg->pls_range.length);
			invalid++;
			removed += mark_lseg_invalid(lseg, tmp_list);
		}
	dprintk("%s:Return %i\n", __func__, invalid - removed);
	return invalid - removed;
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}

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/* note free_me must contain lsegs from a single layout_hdr */
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void
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pnfs_free_lseg_list(struct list_head *free_me)
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{
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	struct pnfs_layout_segment *lseg, *tmp;
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	struct pnfs_layout_hdr *lo;

	if (list_empty(free_me))
		return;

	lo = list_first_entry(free_me, struct pnfs_layout_segment,
			      pls_list)->pls_layout;
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	if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
		struct nfs_client *clp;

		clp = NFS_SERVER(lo->plh_inode)->nfs_client;
		spin_lock(&clp->cl_lock);
		list_del_init(&lo->plh_layouts);
		spin_unlock(&clp->cl_lock);
	}
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	list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
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		list_del(&lseg->pls_list);
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		free_lseg(lseg);
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	}
}

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void
pnfs_destroy_layout(struct nfs_inode *nfsi)
{
	struct pnfs_layout_hdr *lo;
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	LIST_HEAD(tmp_list);
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	spin_lock(&nfsi->vfs_inode.i_lock);
	lo = nfsi->layout;
	if (lo) {
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		lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
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		mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
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	}
	spin_unlock(&nfsi->vfs_inode.i_lock);
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	pnfs_free_lseg_list(&tmp_list);
}

/*
 * Called by the state manger to remove all layouts established under an
 * expired lease.
 */
void
pnfs_destroy_all_layouts(struct nfs_client *clp)
{
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	struct nfs_server *server;
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	struct pnfs_layout_hdr *lo;
	LIST_HEAD(tmp_list);

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	nfs4_deviceid_mark_client_invalid(clp);
	nfs4_deviceid_purge_client(clp);

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	spin_lock(&clp->cl_lock);
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	rcu_read_lock();
	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
		if (!list_empty(&server->layouts))
			list_splice_init(&server->layouts, &tmp_list);
	}
	rcu_read_unlock();
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	spin_unlock(&clp->cl_lock);

	while (!list_empty(&tmp_list)) {
		lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
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				plh_layouts);
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		dprintk("%s freeing layout for inode %lu\n", __func__,
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			lo->plh_inode->i_ino);
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		list_del_init(&lo->plh_layouts);
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		pnfs_destroy_layout(NFS_I(lo->plh_inode));
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	}
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}

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/* update lo->plh_stateid with new if is more recent */
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void
pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
			bool update_barrier)
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{
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	u32 oldseq, newseq;
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	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
	newseq = be32_to_cpu(new->seqid);
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	if ((int)(newseq - oldseq) > 0) {
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		nfs4_stateid_copy(&lo->plh_stateid, new);
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		if (update_barrier) {
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			u32 new_barrier = be32_to_cpu(new->seqid);
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			if ((int)(new_barrier - lo->plh_barrier))
				lo->plh_barrier = new_barrier;
		} else {
			/* Because of wraparound, we want to keep the barrier
			 * "close" to the current seqids.  It needs to be
			 * within 2**31 to count as "behind", so if it
			 * gets too near that limit, give us a litle leeway
			 * and bring it to within 2**30.
			 * NOTE - and yes, this is all unsigned arithmetic.
			 */
			if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
				lo->plh_barrier = newseq - (1 << 30);
		}
	}
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}

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/* lget is set to 1 if called from inside send_layoutget call chain */
static bool
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pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
			int lget)
{
	if ((stateid) &&
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	    (int)(lo->plh_barrier - be32_to_cpu(stateid->seqid)) >= 0)
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		return true;
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	return lo->plh_block_lgets ||
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		test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
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		test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
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		(list_empty(&lo->plh_segs) &&
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		 (atomic_read(&lo->plh_outstanding) > lget));
}

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int
pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
			      struct nfs4_state *open_state)
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{
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	int status = 0;
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	dprintk("--> %s\n", __func__);
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	spin_lock(&lo->plh_inode->i_lock);
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	if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
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		status = -EAGAIN;
	} else if (list_empty(&lo->plh_segs)) {
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		int seq;

		do {
			seq = read_seqbegin(&open_state->seqlock);
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			nfs4_stateid_copy(dst, &open_state->stateid);
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		} while (read_seqretry(&open_state->seqlock, seq));
	} else
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		nfs4_stateid_copy(dst, &lo->plh_stateid);
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	spin_unlock(&lo->plh_inode->i_lock);
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	dprintk("<-- %s\n", __func__);
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	return status;
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}

/*
* Get layout from server.
*    for now, assume that whole file layouts are requested.
*    arg->offset: 0
*    arg->length: all ones
*/
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static struct pnfs_layout_segment *
send_layoutget(struct pnfs_layout_hdr *lo,
	   struct nfs_open_context *ctx,
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	   struct pnfs_layout_range *range,
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	   gfp_t gfp_flags)
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{
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	struct inode *ino = lo->plh_inode;
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	struct nfs_server *server = NFS_SERVER(ino);
	struct nfs4_layoutget *lgp;
	struct pnfs_layout_segment *lseg = NULL;
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	struct page **pages = NULL;
	int i;
	u32 max_resp_sz, max_pages;
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	dprintk("--> %s\n", __func__);
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	BUG_ON(ctx == NULL);
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	lgp = kzalloc(sizeof(*lgp), gfp_flags);
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	if (lgp == NULL)
586
		return NULL;
587 588 589

	/* allocate pages for xdr post processing */
	max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
590
	max_pages = nfs_page_array_len(0, max_resp_sz);
591

592
	pages = kcalloc(max_pages, sizeof(struct page *), gfp_flags);
593 594 595 596
	if (!pages)
		goto out_err_free;

	for (i = 0; i < max_pages; i++) {
597
		pages[i] = alloc_page(gfp_flags);
598 599 600 601
		if (!pages[i])
			goto out_err_free;
	}

602 603 604
	lgp->args.minlength = PAGE_CACHE_SIZE;
	if (lgp->args.minlength > range->length)
		lgp->args.minlength = range->length;
605
	lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
606
	lgp->args.range = *range;
607 608 609
	lgp->args.type = server->pnfs_curr_ld->id;
	lgp->args.inode = ino;
	lgp->args.ctx = get_nfs_open_context(ctx);
610 611
	lgp->args.layout.pages = pages;
	lgp->args.layout.pglen = max_pages * PAGE_SIZE;
612
	lgp->lsegpp = &lseg;
613
	lgp->gfp_flags = gfp_flags;
614 615 616 617 618

	/* Synchronously retrieve layout information from server and
	 * store in lseg.
	 */
	nfs4_proc_layoutget(lgp);
619
	if (!lseg) {
620
		/* remember that LAYOUTGET failed and suspend trying */
621
		set_bit(lo_fail_bit(range->iomode), &lo->plh_flags);
622
	}
623 624 625 626 627 628

	/* free xdr pages */
	for (i = 0; i < max_pages; i++)
		__free_page(pages[i]);
	kfree(pages);

629
	return lseg;
630 631 632 633 634 635 636 637 638 639 640 641 642

out_err_free:
	/* free any allocated xdr pages, lgp as it's not used */
	if (pages) {
		for (i = 0; i < max_pages; i++) {
			if (!pages[i])
				break;
			__free_page(pages[i]);
		}
		kfree(pages);
	}
	kfree(lgp);
	return NULL;
643 644
}

B
Benny Halevy 已提交
645 646 647 648 649 650 651 652 653 654 655 656 657 658 659
/* Initiates a LAYOUTRETURN(FILE) */
int
_pnfs_return_layout(struct inode *ino)
{
	struct pnfs_layout_hdr *lo = NULL;
	struct nfs_inode *nfsi = NFS_I(ino);
	LIST_HEAD(tmp_list);
	struct nfs4_layoutreturn *lrp;
	nfs4_stateid stateid;
	int status = 0;

	dprintk("--> %s\n", __func__);

	spin_lock(&ino->i_lock);
	lo = nfsi->layout;
660
	if (!lo) {
B
Benny Halevy 已提交
661
		spin_unlock(&ino->i_lock);
662 663
		dprintk("%s: no layout to return\n", __func__);
		return status;
B
Benny Halevy 已提交
664 665 666 667
	}
	stateid = nfsi->layout->plh_stateid;
	/* Reference matched in nfs4_layoutreturn_release */
	get_layout_hdr(lo);
668 669
	mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
	lo->plh_block_lgets++;
B
Benny Halevy 已提交
670 671 672 673 674 675 676 677
	spin_unlock(&ino->i_lock);
	pnfs_free_lseg_list(&tmp_list);

	WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags));

	lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
	if (unlikely(lrp == NULL)) {
		status = -ENOMEM;
678 679
		set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags);
		set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags);
680
		put_layout_hdr(lo);
B
Benny Halevy 已提交
681 682 683 684 685 686
		goto out;
	}

	lrp->args.stateid = stateid;
	lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
	lrp->args.inode = ino;
T
Trond Myklebust 已提交
687
	lrp->args.layout = lo;
B
Benny Halevy 已提交
688 689 690 691 692 693 694
	lrp->clp = NFS_SERVER(ino)->nfs_client;

	status = nfs4_proc_layoutreturn(lrp);
out:
	dprintk("<-- %s status: %d\n", __func__, status);
	return status;
}
695
EXPORT_SYMBOL_GPL(_pnfs_return_layout);
B
Benny Halevy 已提交
696

F
Fred Isaman 已提交
697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762
bool pnfs_roc(struct inode *ino)
{
	struct pnfs_layout_hdr *lo;
	struct pnfs_layout_segment *lseg, *tmp;
	LIST_HEAD(tmp_list);
	bool found = false;

	spin_lock(&ino->i_lock);
	lo = NFS_I(ino)->layout;
	if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
	    test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
		goto out_nolayout;
	list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
			mark_lseg_invalid(lseg, &tmp_list);
			found = true;
		}
	if (!found)
		goto out_nolayout;
	lo->plh_block_lgets++;
	get_layout_hdr(lo); /* matched in pnfs_roc_release */
	spin_unlock(&ino->i_lock);
	pnfs_free_lseg_list(&tmp_list);
	return true;

out_nolayout:
	spin_unlock(&ino->i_lock);
	return false;
}

void pnfs_roc_release(struct inode *ino)
{
	struct pnfs_layout_hdr *lo;

	spin_lock(&ino->i_lock);
	lo = NFS_I(ino)->layout;
	lo->plh_block_lgets--;
	put_layout_hdr_locked(lo);
	spin_unlock(&ino->i_lock);
}

void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
{
	struct pnfs_layout_hdr *lo;

	spin_lock(&ino->i_lock);
	lo = NFS_I(ino)->layout;
	if ((int)(barrier - lo->plh_barrier) > 0)
		lo->plh_barrier = barrier;
	spin_unlock(&ino->i_lock);
}

bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
{
	struct nfs_inode *nfsi = NFS_I(ino);
	struct pnfs_layout_segment *lseg;
	bool found = false;

	spin_lock(&ino->i_lock);
	list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
		if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
			found = true;
			break;
		}
	if (!found) {
		struct pnfs_layout_hdr *lo = nfsi->layout;
763
		u32 current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
F
Fred Isaman 已提交
764 765 766 767 768 769 770 771 772 773

		/* Since close does not return a layout stateid for use as
		 * a barrier, we choose the worst-case barrier.
		 */
		*barrier = current_seqid + atomic_read(&lo->plh_outstanding);
	}
	spin_unlock(&ino->i_lock);
	return found;
}

774 775 776 777 778 779
/*
 * Compare two layout segments for sorting into layout cache.
 * We want to preferentially return RW over RO layouts, so ensure those
 * are seen first.
 */
static s64
780 781
cmp_layout(struct pnfs_layout_range *l1,
	   struct pnfs_layout_range *l2)
782
{
783 784 785 786 787 788 789 790 791 792 793 794
	s64 d;

	/* high offset > low offset */
	d = l1->offset - l2->offset;
	if (d)
		return d;

	/* short length > long length */
	d = l2->length - l1->length;
	if (d)
		return d;

795
	/* read > read/write */
796
	return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
797 798
}

799 800 801 802
static void
pnfs_insert_layout(struct pnfs_layout_hdr *lo,
		   struct pnfs_layout_segment *lseg)
{
803 804
	struct pnfs_layout_segment *lp;

805 806
	dprintk("%s:Begin\n", __func__);

807 808
	assert_spin_locked(&lo->plh_inode->i_lock);
	list_for_each_entry(lp, &lo->plh_segs, pls_list) {
809
		if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
810
			continue;
811
		list_add_tail(&lseg->pls_list, &lp->pls_list);
812 813 814
		dprintk("%s: inserted lseg %p "
			"iomode %d offset %llu length %llu before "
			"lp %p iomode %d offset %llu length %llu\n",
815 816 817 818
			__func__, lseg, lseg->pls_range.iomode,
			lseg->pls_range.offset, lseg->pls_range.length,
			lp, lp->pls_range.iomode, lp->pls_range.offset,
			lp->pls_range.length);
819
		goto out;
820
	}
821 822 823 824 825 826
	list_add_tail(&lseg->pls_list, &lo->plh_segs);
	dprintk("%s: inserted lseg %p "
		"iomode %d offset %llu length %llu at tail\n",
		__func__, lseg, lseg->pls_range.iomode,
		lseg->pls_range.offset, lseg->pls_range.length);
out:
827
	get_layout_hdr(lo);
828 829

	dprintk("%s:Return\n", __func__);
830 831 832
}

static struct pnfs_layout_hdr *
833 834 835
alloc_init_layout_hdr(struct inode *ino,
		      struct nfs_open_context *ctx,
		      gfp_t gfp_flags)
836 837 838
{
	struct pnfs_layout_hdr *lo;

839
	lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
840 841
	if (!lo)
		return NULL;
842
	atomic_set(&lo->plh_refcount, 1);
843 844
	INIT_LIST_HEAD(&lo->plh_layouts);
	INIT_LIST_HEAD(&lo->plh_segs);
F
Fred Isaman 已提交
845
	INIT_LIST_HEAD(&lo->plh_bulk_recall);
846
	lo->plh_inode = ino;
847
	lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred);
848 849 850 851
	return lo;
}

static struct pnfs_layout_hdr *
852 853 854
pnfs_find_alloc_layout(struct inode *ino,
		       struct nfs_open_context *ctx,
		       gfp_t gfp_flags)
855 856 857 858 859 860 861
{
	struct nfs_inode *nfsi = NFS_I(ino);
	struct pnfs_layout_hdr *new = NULL;

	dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);

	assert_spin_locked(&ino->i_lock);
862 863 864 865 866 867
	if (nfsi->layout) {
		if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
			return NULL;
		else
			return nfsi->layout;
	}
868
	spin_unlock(&ino->i_lock);
869
	new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
870 871 872 873 874
	spin_lock(&ino->i_lock);

	if (likely(nfsi->layout == NULL))	/* Won the race? */
		nfsi->layout = new;
	else
875
		pnfs_free_layout_hdr(new);
876 877 878
	return nfsi->layout;
}

879 880 881 882 883 884 885 886 887 888 889 890
/*
 * iomode matching rules:
 * iomode	lseg	match
 * -----	-----	-----
 * ANY		READ	true
 * ANY		RW	true
 * RW		READ	false
 * RW		RW	true
 * READ		READ	true
 * READ		RW	true
 */
static int
891 892
is_matching_lseg(struct pnfs_layout_range *ls_range,
		 struct pnfs_layout_range *range)
893
{
894 895 896 897 898 899 900 901 902 903 904
	struct pnfs_layout_range range1;

	if ((range->iomode == IOMODE_RW &&
	     ls_range->iomode != IOMODE_RW) ||
	    !lo_seg_intersecting(ls_range, range))
		return 0;

	/* range1 covers only the first byte in the range */
	range1 = *range;
	range1.length = 1;
	return lo_seg_contained(ls_range, &range1);
905 906 907 908 909
}

/*
 * lookup range in layout
 */
910
static struct pnfs_layout_segment *
911 912
pnfs_find_lseg(struct pnfs_layout_hdr *lo,
		struct pnfs_layout_range *range)
913
{
914 915 916 917
	struct pnfs_layout_segment *lseg, *ret = NULL;

	dprintk("%s:Begin\n", __func__);

918 919
	assert_spin_locked(&lo->plh_inode->i_lock);
	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
920
		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
921
		    is_matching_lseg(&lseg->pls_range, range)) {
F
Fred Isaman 已提交
922
			ret = get_lseg(lseg);
923 924
			break;
		}
925
		if (lseg->pls_range.offset > range->offset)
926 927 928 929
			break;
	}

	dprintk("%s:Return lseg %p ref %d\n",
930
		__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
931
	return ret;
932 933 934 935 936 937
}

/*
 * Layout segment is retreived from the server if not cached.
 * The appropriate layout segment is referenced and returned to the caller.
 */
938
struct pnfs_layout_segment *
939 940
pnfs_update_layout(struct inode *ino,
		   struct nfs_open_context *ctx,
941 942
		   loff_t pos,
		   u64 count,
943 944
		   enum pnfs_iomode iomode,
		   gfp_t gfp_flags)
945
{
946 947 948 949 950
	struct pnfs_layout_range arg = {
		.iomode = iomode,
		.offset = pos,
		.length = count,
	};
951
	unsigned pg_offset;
952
	struct nfs_inode *nfsi = NFS_I(ino);
953 954
	struct nfs_server *server = NFS_SERVER(ino);
	struct nfs_client *clp = server->nfs_client;
955 956
	struct pnfs_layout_hdr *lo;
	struct pnfs_layout_segment *lseg = NULL;
957
	bool first = false;
958 959 960 961

	if (!pnfs_enabled_sb(NFS_SERVER(ino)))
		return NULL;
	spin_lock(&ino->i_lock);
962
	lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
963 964 965 966 967
	if (lo == NULL) {
		dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__);
		goto out_unlock;
	}

F
Fred Isaman 已提交
968
	/* Do we even need to bother with this? */
969
	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
F
Fred Isaman 已提交
970
		dprintk("%s matches recall, use MDS\n", __func__);
971 972 973 974
		goto out_unlock;
	}

	/* if LAYOUTGET already failed once we don't try again */
975
	if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
976 977
		goto out_unlock;

978
	/* Check to see if the layout for the given range already exists */
979
	lseg = pnfs_find_lseg(lo, &arg);
980 981 982
	if (lseg)
		goto out_unlock;

F
Fred Isaman 已提交
983
	if (pnfs_layoutgets_blocked(lo, NULL, 0))
984 985 986
		goto out_unlock;
	atomic_inc(&lo->plh_outstanding);

987
	get_layout_hdr(lo);
988 989 990 991
	if (list_empty(&lo->plh_segs))
		first = true;
	spin_unlock(&ino->i_lock);
	if (first) {
992 993 994 995 996
		/* The lo must be on the clp list if there is any
		 * chance of a CB_LAYOUTRECALL(FILE) coming in.
		 */
		spin_lock(&clp->cl_lock);
		BUG_ON(!list_empty(&lo->plh_layouts));
997
		list_add_tail(&lo->plh_layouts, &server->layouts);
998 999
		spin_unlock(&clp->cl_lock);
	}
1000

1001 1002 1003 1004 1005
	pg_offset = arg.offset & ~PAGE_CACHE_MASK;
	if (pg_offset) {
		arg.offset -= pg_offset;
		arg.length += pg_offset;
	}
1006 1007
	if (arg.length != NFS4_MAX_UINT64)
		arg.length = PAGE_CACHE_ALIGN(arg.length);
1008

1009
	lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
1010 1011 1012 1013
	if (!lseg && first) {
		spin_lock(&clp->cl_lock);
		list_del_init(&lo->plh_layouts);
		spin_unlock(&clp->cl_lock);
1014
	}
1015
	atomic_dec(&lo->plh_outstanding);
1016
	put_layout_hdr(lo);
1017 1018
out:
	dprintk("%s end, state 0x%lx lseg %p\n", __func__,
1019
		nfsi->layout ? nfsi->layout->plh_flags : -1, lseg);
1020 1021 1022 1023 1024
	return lseg;
out_unlock:
	spin_unlock(&ino->i_lock);
	goto out;
}
1025
EXPORT_SYMBOL_GPL(pnfs_update_layout);
1026 1027 1028 1029 1030 1031 1032

int
pnfs_layout_process(struct nfs4_layoutget *lgp)
{
	struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
	struct nfs4_layoutget_res *res = &lgp->res;
	struct pnfs_layout_segment *lseg;
1033
	struct inode *ino = lo->plh_inode;
1034 1035 1036
	int status = 0;

	/* Inject layout blob into I/O device driver */
1037
	lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048
	if (!lseg || IS_ERR(lseg)) {
		if (!lseg)
			status = -ENOMEM;
		else
			status = PTR_ERR(lseg);
		dprintk("%s: Could not allocate layout: error %d\n",
		       __func__, status);
		goto out;
	}

	spin_lock(&ino->i_lock);
1049
	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
F
Fred Isaman 已提交
1050 1051 1052 1053 1054 1055 1056 1057
		dprintk("%s forget reply due to recall\n", __func__);
		goto out_forget_reply;
	}

	if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
		dprintk("%s forget reply due to state\n", __func__);
		goto out_forget_reply;
	}
1058
	init_lseg(lo, lseg);
1059
	lseg->pls_range = res->range;
F
Fred Isaman 已提交
1060
	*lgp->lsegpp = get_lseg(lseg);
1061 1062
	pnfs_insert_layout(lo, lseg);

F
Fred Isaman 已提交
1063 1064 1065 1066 1067
	if (res->return_on_close) {
		set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
		set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
	}

1068
	/* Done processing layoutget. Set the layout stateid */
F
Fred Isaman 已提交
1069
	pnfs_set_layout_stateid(lo, &res->stateid, false);
1070 1071 1072
	spin_unlock(&ino->i_lock);
out:
	return status;
F
Fred Isaman 已提交
1073 1074 1075 1076 1077 1078

out_forget_reply:
	spin_unlock(&ino->i_lock);
	lseg->pls_layout = lo;
	NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
	goto out;
1079 1080
}

1081 1082 1083 1084 1085
void
pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
	BUG_ON(pgio->pg_lseg != NULL);

1086 1087 1088 1089
	if (req->wb_offset != req->wb_pgbase) {
		nfs_pageio_reset_read_mds(pgio);
		return;
	}
1090 1091 1092 1093 1094 1095
	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
					   req->wb_context,
					   req_offset(req),
					   req->wb_bytes,
					   IOMODE_READ,
					   GFP_KERNEL);
1096 1097
	/* If no lseg, fall back to read through mds */
	if (pgio->pg_lseg == NULL)
1098
		nfs_pageio_reset_read_mds(pgio);
1099

1100 1101 1102 1103 1104 1105 1106 1107
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);

void
pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
	BUG_ON(pgio->pg_lseg != NULL);

1108 1109 1110 1111
	if (req->wb_offset != req->wb_pgbase) {
		nfs_pageio_reset_write_mds(pgio);
		return;
	}
1112 1113 1114 1115 1116 1117
	pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
					   req->wb_context,
					   req_offset(req),
					   req->wb_bytes,
					   IOMODE_RW,
					   GFP_NOFS);
1118 1119
	/* If no lseg, fall back to write through mds */
	if (pgio->pg_lseg == NULL)
1120
		nfs_pageio_reset_write_mds(pgio);
1121 1122 1123
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);

1124
bool
1125 1126
pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode,
		      const struct nfs_pgio_completion_ops *compl_ops)
1127 1128 1129 1130 1131 1132
{
	struct nfs_server *server = NFS_SERVER(inode);
	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;

	if (ld == NULL)
		return false;
1133 1134
	nfs_pageio_init(pgio, inode, ld->pg_read_ops, compl_ops,
			server->rsize, 0);
1135 1136 1137 1138
	return true;
}

bool
1139 1140 1141
pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode,
		       int ioflags,
		       const struct nfs_pgio_completion_ops *compl_ops)
1142 1143 1144 1145 1146 1147
{
	struct nfs_server *server = NFS_SERVER(inode);
	struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;

	if (ld == NULL)
		return false;
1148 1149
	nfs_pageio_init(pgio, inode, ld->pg_write_ops, compl_ops,
			server->wsize, ioflags);
1150 1151 1152
	return true;
}

1153
bool
1154 1155
pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
		     struct nfs_page *req)
1156
{
1157 1158
	if (pgio->pg_lseg == NULL)
		return nfs_generic_pg_test(pgio, prev, req);
1159

1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175
	/*
	 * Test if a nfs_page is fully contained in the pnfs_layout_range.
	 * Note that this test makes several assumptions:
	 * - that the previous nfs_page in the struct nfs_pageio_descriptor
	 *   is known to lie within the range.
	 *   - that the nfs_page being tested is known to be contiguous with the
	 *   previous nfs_page.
	 *   - Layout ranges are page aligned, so we only have to test the
	 *   start offset of the request.
	 *
	 * Please also note that 'end_offset' is actually the offset of the
	 * first byte that lies outside the pnfs_layout_range. FIXME?
	 *
	 */
	return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
					 pgio->pg_lseg->pls_range.length);
1176
}
1177
EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
1178

1179
int pnfs_write_done_resend_to_mds(struct inode *inode,
1180 1181
				struct list_head *head,
				const struct nfs_pgio_completion_ops *compl_ops)
1182 1183 1184 1185 1186
{
	struct nfs_pageio_descriptor pgio;
	LIST_HEAD(failed);

	/* Resend all requests through the MDS */
1187
	nfs_pageio_init_write_mds(&pgio, inode, FLUSH_STABLE, compl_ops);
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206
	while (!list_empty(head)) {
		struct nfs_page *req = nfs_list_entry(head->next);

		nfs_list_remove_request(req);
		if (!nfs_pageio_add_request(&pgio, req))
			nfs_list_add_request(req, &failed);
	}
	nfs_pageio_complete(&pgio);

	if (!list_empty(&failed)) {
		/* For some reason our attempt to resend pages. Mark the
		 * overall send request as having failed, and let
		 * nfs_writeback_release_full deal with the error.
		 */
		list_move(&failed, head);
		return -EIO;
	}
	return 0;
}
1207
EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
1208

1209 1210
static void pnfs_ld_handle_write_error(struct nfs_write_data *data)
{
1211 1212 1213 1214
	struct nfs_pgio_header *hdr = data->header;

	dprintk("pnfs write error = %d\n", hdr->pnfs_error);
	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1215
	    PNFS_LAYOUTRET_ON_ERROR) {
1216 1217
		clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
		pnfs_return_layout(hdr->inode);
1218
	}
1219 1220
	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
		data->task.tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
1221 1222
							&hdr->pages,
							hdr->completion_ops);
1223 1224
}

1225 1226 1227
/*
 * Called by non rpc-based layout drivers
 */
1228
void pnfs_ld_write_done(struct nfs_write_data *data)
1229
{
1230 1231 1232
	struct nfs_pgio_header *hdr = data->header;

	if (!hdr->pnfs_error) {
1233
		pnfs_set_layoutcommit(data);
1234
		hdr->mds_ops->rpc_call_done(&data->task, data);
1235 1236
	} else
		pnfs_ld_handle_write_error(data);
1237
	hdr->mds_ops->rpc_release(data);
1238
}
1239
EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
1240

1241 1242 1243 1244
static void
pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
		struct nfs_write_data *data)
{
1245 1246
	struct nfs_pgio_header *hdr = data->header;

1247 1248 1249 1250 1251
	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
		list_splice_tail_init(&hdr->pages, &desc->pg_list);
		nfs_pageio_reset_write_mds(desc);
		desc->pg_recoalesce = 1;
	}
1252 1253 1254 1255
	nfs_writedata_release(data);
}

static enum pnfs_try_status
1256
pnfs_try_to_write_data(struct nfs_write_data *wdata,
1257 1258 1259
			const struct rpc_call_ops *call_ops,
			struct pnfs_layout_segment *lseg,
			int how)
1260
{
1261 1262
	struct nfs_pgio_header *hdr = wdata->header;
	struct inode *inode = hdr->inode;
1263 1264 1265
	enum pnfs_try_status trypnfs;
	struct nfs_server *nfss = NFS_SERVER(inode);

1266
	hdr->mds_ops = call_ops;
1267 1268 1269 1270

	dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
		inode->i_ino, wdata->args.count, wdata->args.offset, how);
	trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how);
1271
	if (trypnfs != PNFS_NOT_ATTEMPTED)
1272 1273 1274 1275 1276
		nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
	return trypnfs;
}

1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287
static void
pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *head, int how)
{
	struct nfs_write_data *data;
	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
	struct pnfs_layout_segment *lseg = desc->pg_lseg;

	desc->pg_lseg = NULL;
	while (!list_empty(head)) {
		enum pnfs_try_status trypnfs;

1288
		data = list_first_entry(head, struct nfs_write_data, list);
1289 1290 1291 1292 1293 1294 1295 1296 1297
		list_del_init(&data->list);

		trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
		if (trypnfs == PNFS_NOT_ATTEMPTED)
			pnfs_write_through_mds(desc, data);
	}
	put_lseg(lseg);
}

1298 1299 1300 1301 1302 1303
static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
{
	put_lseg(hdr->lseg);
	nfs_writehdr_free(hdr);
}

1304 1305 1306
int
pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
{
1307 1308
	struct nfs_write_header *whdr;
	struct nfs_pgio_header *hdr;
1309 1310
	int ret;

1311 1312
	whdr = nfs_writehdr_alloc();
	if (!whdr) {
1313
		desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1314 1315
		put_lseg(desc->pg_lseg);
		desc->pg_lseg = NULL;
1316
		return -ENOMEM;
1317
	}
1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328
	hdr = &whdr->header;
	nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
	hdr->lseg = get_lseg(desc->pg_lseg);
	atomic_inc(&hdr->refcnt);
	ret = nfs_generic_flush(desc, hdr);
	if (ret != 0) {
		put_lseg(desc->pg_lseg);
		desc->pg_lseg = NULL;
	} else
		pnfs_do_multiple_writes(desc, &hdr->rpc_list, desc->pg_ioflags);
	if (atomic_dec_and_test(&hdr->refcnt))
1329
		hdr->completion_ops->completion(hdr);
1330
	return ret;
1331 1332 1333
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);

1334
int pnfs_read_done_resend_to_mds(struct inode *inode,
1335 1336
				struct list_head *head,
				const struct nfs_pgio_completion_ops *compl_ops)
1337 1338
{
	struct nfs_pageio_descriptor pgio;
1339
	LIST_HEAD(failed);
1340

1341
	/* Resend all requests through the MDS */
1342
	nfs_pageio_init_read_mds(&pgio, inode, compl_ops);
1343 1344
	while (!list_empty(head)) {
		struct nfs_page *req = nfs_list_entry(head->next);
1345 1346

		nfs_list_remove_request(req);
1347 1348
		if (!nfs_pageio_add_request(&pgio, req))
			nfs_list_add_request(req, &failed);
1349 1350
	}
	nfs_pageio_complete(&pgio);
1351 1352 1353 1354 1355 1356 1357

	if (!list_empty(&failed)) {
		list_move(&failed, head);
		return -EIO;
	}
	return 0;
}
1358
EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
1359 1360 1361

static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
{
1362 1363 1364 1365
	struct nfs_pgio_header *hdr = data->header;

	dprintk("pnfs read error = %d\n", hdr->pnfs_error);
	if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1366
	    PNFS_LAYOUTRET_ON_ERROR) {
1367 1368
		clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
		pnfs_return_layout(hdr->inode);
1369
	}
1370 1371
	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
		data->task.tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
1372 1373
							&hdr->pages,
							hdr->completion_ops);
1374 1375
}

1376 1377 1378
/*
 * Called by non rpc-based layout drivers
 */
1379
void pnfs_ld_read_done(struct nfs_read_data *data)
1380
{
1381 1382 1383
	struct nfs_pgio_header *hdr = data->header;

	if (likely(!hdr->pnfs_error)) {
1384
		__nfs4_read_done_cb(data);
1385
		hdr->mds_ops->rpc_call_done(&data->task, data);
1386 1387
	} else
		pnfs_ld_handle_read_error(data);
1388
	hdr->mds_ops->rpc_release(data);
1389 1390 1391
}
EXPORT_SYMBOL_GPL(pnfs_ld_read_done);

1392 1393 1394 1395
static void
pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
		struct nfs_read_data *data)
{
1396 1397
	struct nfs_pgio_header *hdr = data->header;

1398 1399 1400 1401 1402
	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
		list_splice_tail_init(&hdr->pages, &desc->pg_list);
		nfs_pageio_reset_read_mds(desc);
		desc->pg_recoalesce = 1;
	}
1403 1404 1405
	nfs_readdata_release(data);
}

A
Andy Adamson 已提交
1406 1407 1408
/*
 * Call the appropriate parallel I/O subsystem read function.
 */
1409
static enum pnfs_try_status
A
Andy Adamson 已提交
1410
pnfs_try_to_read_data(struct nfs_read_data *rdata,
1411 1412
		       const struct rpc_call_ops *call_ops,
		       struct pnfs_layout_segment *lseg)
A
Andy Adamson 已提交
1413
{
1414 1415
	struct nfs_pgio_header *hdr = rdata->header;
	struct inode *inode = hdr->inode;
A
Andy Adamson 已提交
1416 1417 1418
	struct nfs_server *nfss = NFS_SERVER(inode);
	enum pnfs_try_status trypnfs;

1419
	hdr->mds_ops = call_ops;
A
Andy Adamson 已提交
1420 1421 1422 1423 1424

	dprintk("%s: Reading ino:%lu %u@%llu\n",
		__func__, inode->i_ino, rdata->args.count, rdata->args.offset);

	trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata);
1425
	if (trypnfs != PNFS_NOT_ATTEMPTED)
A
Andy Adamson 已提交
1426 1427 1428 1429
		nfs_inc_stats(inode, NFSIOS_PNFS_READ);
	dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
	return trypnfs;
}
A
Andy Adamson 已提交
1430

1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441
static void
pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
{
	struct nfs_read_data *data;
	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
	struct pnfs_layout_segment *lseg = desc->pg_lseg;

	desc->pg_lseg = NULL;
	while (!list_empty(head)) {
		enum pnfs_try_status trypnfs;

1442
		data = list_first_entry(head, struct nfs_read_data, list);
1443 1444 1445 1446 1447 1448 1449 1450 1451
		list_del_init(&data->list);

		trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
		if (trypnfs == PNFS_NOT_ATTEMPTED)
			pnfs_read_through_mds(desc, data);
	}
	put_lseg(lseg);
}

1452 1453 1454 1455 1456 1457
static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
{
	put_lseg(hdr->lseg);
	nfs_readhdr_free(hdr);
}

1458 1459 1460
int
pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
{
1461 1462
	struct nfs_read_header *rhdr;
	struct nfs_pgio_header *hdr;
1463 1464
	int ret;

1465 1466
	rhdr = nfs_readhdr_alloc();
	if (!rhdr) {
1467
		desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1468
		ret = -ENOMEM;
1469 1470 1471 1472
		put_lseg(desc->pg_lseg);
		desc->pg_lseg = NULL;
		return ret;
	}
1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483
	hdr = &rhdr->header;
	nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
	hdr->lseg = get_lseg(desc->pg_lseg);
	atomic_inc(&hdr->refcnt);
	ret = nfs_generic_pagein(desc, hdr);
	if (ret != 0) {
		put_lseg(desc->pg_lseg);
		desc->pg_lseg = NULL;
	} else
		pnfs_do_multiple_reads(desc, &hdr->rpc_list);
	if (atomic_dec_and_test(&hdr->refcnt))
1484
		hdr->completion_ops->completion(hdr);
1485
	return ret;
1486 1487 1488
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);

A
Andy Adamson 已提交
1489
/*
1490
 * There can be multiple RW segments.
A
Andy Adamson 已提交
1491
 */
1492
static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
A
Andy Adamson 已提交
1493
{
1494
	struct pnfs_layout_segment *lseg;
A
Andy Adamson 已提交
1495

1496 1497 1498 1499 1500
	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
		if (lseg->pls_range.iomode == IOMODE_RW &&
		    test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
			list_add(&lseg->pls_lc_list, listp);
	}
A
Andy Adamson 已提交
1501 1502
}

P
Peng Tao 已提交
1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514
void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
{
	if (lseg->pls_range.iomode == IOMODE_RW) {
		dprintk("%s Setting layout IOMODE_RW fail bit\n", __func__);
		set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
	} else {
		dprintk("%s Setting layout IOMODE_READ fail bit\n", __func__);
		set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
	}
}
EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);

A
Andy Adamson 已提交
1515 1516 1517
void
pnfs_set_layoutcommit(struct nfs_write_data *wdata)
{
1518 1519 1520
	struct nfs_pgio_header *hdr = wdata->header;
	struct inode *inode = hdr->inode;
	struct nfs_inode *nfsi = NFS_I(inode);
1521
	loff_t end_pos = wdata->mds_offset + wdata->res.count;
1522
	bool mark_as_dirty = false;
A
Andy Adamson 已提交
1523

1524
	spin_lock(&inode->i_lock);
A
Andy Adamson 已提交
1525
	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
1526
		mark_as_dirty = true;
A
Andy Adamson 已提交
1527
		dprintk("%s: Set layoutcommit for inode %lu ",
1528
			__func__, inode->i_ino);
A
Andy Adamson 已提交
1529
	}
1530
	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
1531
		/* references matched in nfs4_layoutcommit_release */
1532
		get_lseg(hdr->lseg);
1533
	}
1534 1535
	if (end_pos > nfsi->layout->plh_lwb)
		nfsi->layout->plh_lwb = end_pos;
1536
	spin_unlock(&inode->i_lock);
1537
	dprintk("%s: lseg %p end_pos %llu\n",
1538
		__func__, hdr->lseg, nfsi->layout->plh_lwb);
1539 1540 1541 1542

	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
	if (mark_as_dirty)
1543
		mark_inode_dirty_sync(inode);
A
Andy Adamson 已提交
1544 1545 1546
}
EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);

A
Andy Adamson 已提交
1547 1548 1549 1550 1551 1552 1553 1554
void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
{
	struct nfs_server *nfss = NFS_SERVER(data->args.inode);

	if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
		nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
}

1555 1556 1557 1558 1559 1560 1561 1562
/*
 * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
 * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
 * data to disk to allow the server to recover the data if it crashes.
 * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
 * is off, and a COMMIT is sent to a data server, or
 * if WRITEs to a data server return NFS_DATA_SYNC.
 */
A
Andy Adamson 已提交
1563
int
1564
pnfs_layoutcommit_inode(struct inode *inode, bool sync)
A
Andy Adamson 已提交
1565 1566 1567 1568 1569 1570 1571 1572
{
	struct nfs4_layoutcommit_data *data;
	struct nfs_inode *nfsi = NFS_I(inode);
	loff_t end_pos;
	int status = 0;

	dprintk("--> %s inode %lu\n", __func__, inode->i_ino);

1573 1574 1575
	if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
		return 0;

A
Andy Adamson 已提交
1576 1577
	/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
	data = kzalloc(sizeof(*data), GFP_NOFS);
1578 1579 1580 1581
	if (!data) {
		status = -ENOMEM;
		goto out;
	}
A
Andy Adamson 已提交
1582

P
Peng Tao 已提交
1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596
	if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
		goto out_free;

	if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
		if (!sync) {
			status = -EAGAIN;
			goto out_free;
		}
		status = wait_on_bit_lock(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING,
					nfs_wait_bit_killable, TASK_KILLABLE);
		if (status)
			goto out_free;
	}

1597
	INIT_LIST_HEAD(&data->lseg_list);
1598
	spin_lock(&inode->i_lock);
A
Andy Adamson 已提交
1599
	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
P
Peng Tao 已提交
1600
		clear_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags);
A
Andy Adamson 已提交
1601
		spin_unlock(&inode->i_lock);
P
Peng Tao 已提交
1602 1603
		wake_up_bit(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING);
		goto out_free;
A
Andy Adamson 已提交
1604
	}
1605 1606

	pnfs_list_write_lseg(inode, &data->lseg_list);
A
Andy Adamson 已提交
1607

1608 1609
	end_pos = nfsi->layout->plh_lwb;
	nfsi->layout->plh_lwb = 0;
A
Andy Adamson 已提交
1610

1611
	nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
A
Andy Adamson 已提交
1612 1613 1614
	spin_unlock(&inode->i_lock);

	data->args.inode = inode;
1615
	data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
A
Andy Adamson 已提交
1616 1617 1618 1619 1620 1621 1622 1623
	nfs_fattr_init(&data->fattr);
	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
	data->res.fattr = &data->fattr;
	data->args.lastbytewritten = end_pos - 1;
	data->res.server = NFS_SERVER(inode);

	status = nfs4_proc_layoutcommit(data, sync);
out:
P
Peng Tao 已提交
1624 1625
	if (status)
		mark_inode_dirty_sync(inode);
A
Andy Adamson 已提交
1626 1627
	dprintk("<-- %s status %d\n", __func__, status);
	return status;
P
Peng Tao 已提交
1628 1629 1630
out_free:
	kfree(data);
	goto out;
A
Andy Adamson 已提交
1631
}