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linux/fs/nfs/pnfs.c
Trond Myklebust 2c64c57dfc NFSv4.1: Fix wraparound issues in pnfs_seqid_is_newer() 
Subtraction of signed integers does not have well defined wraparound
semantics in the C99 standard. In order to be wraparound-safe, we
have to use unsigned subtraction, and then cast the result.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-02-19 21:21:01 -05:00

1962 lines
51 KiB
C
Raw Blame History

/*
* 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>
#include <linux/nfs_page.h>
#include <linux/module.h>
#include "internal.h"
#include "pnfs.h"
#include "iostat.h"
#include "nfs4trace.h"
#define NFSDBG_FACILITY NFSDBG_PNFS
#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
/* 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;
}
static struct pnfs_layoutdriver_type *
find_pnfs_driver(u32 id)
{
struct pnfs_layoutdriver_type *local;
spin_lock(&pnfs_spinlock);
local = find_pnfs_driver_locked(id);
if (local != NULL && !try_module_get(local->owner)) {
dprintk("%s: Could not grab reference on module\n", __func__);
local = NULL;
}
spin_unlock(&pnfs_spinlock);
return local;
}
void
unset_pnfs_layoutdriver(struct nfs_server *nfss)
{
if (nfss->pnfs_curr_ld) {
if (nfss->pnfs_curr_ld->clear_layoutdriver)
nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
/* Decrement the MDS count. Purge the deviceid cache if zero */
if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
nfs4_deviceid_purge_client(nfss->nfs_client);
module_put(nfss->pnfs_curr_ld->owner);
}
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
set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
u32 id)
{
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))) {
printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
__func__, id, server->nfs_client->cl_exchange_flags);
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;
}
}
server->pnfs_curr_ld = ld_type;
if (ld_type->set_layoutdriver
&& ld_type->set_layoutdriver(server, mntfh)) {
printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
"driver %u.\n", __func__, id);
module_put(ld_type->owner);
goto out_no_driver;
}
/* Bump the MDS count */
atomic_inc(&server->nfs_client->cl_mds_count);
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;
}
int
pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
{
int status = -EINVAL;
struct pnfs_layoutdriver_type *tmp;
if (ld_type->id == 0) {
printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
return status;
}
if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
printk(KERN_ERR "NFS: %s Layout driver must provide "
"alloc_lseg and free_lseg.\n", __func__);
return status;
}
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 {
printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
__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);
/*
* pNFS client layout cache
*/
/* Need to hold i_lock if caller does not already hold reference */
void
pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
{
atomic_inc(&lo->plh_refcount);
}
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(ino, gfp_flags);
}
static void
pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
{
struct nfs_server *server = NFS_SERVER(lo->plh_inode);
struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
if (!list_empty(&lo->plh_layouts)) {
struct nfs_client *clp = server->nfs_client;
spin_lock(&clp->cl_lock);
list_del_init(&lo->plh_layouts);
spin_unlock(&clp->cl_lock);
}
put_rpccred(lo->plh_lc_cred);
return ld->free_layout_hdr(lo);
}
static void
pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
{
struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
dprintk("%s: freeing layout cache %p\n", __func__, lo);
nfsi->layout = NULL;
/* Reset MDS Threshold I/O counters */
nfsi->write_io = 0;
nfsi->read_io = 0;
}
void
pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
{
struct inode *inode = lo->plh_inode;
if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
pnfs_detach_layout_hdr(lo);
spin_unlock(&inode->i_lock);
pnfs_free_layout_hdr(lo);
}
}
static int
pnfs_iomode_to_fail_bit(u32 iomode)
{
return iomode == IOMODE_RW ?
NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
}
static void
pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
{
lo->plh_retry_timestamp = jiffies;
if (!test_and_set_bit(fail_bit, &lo->plh_flags))
atomic_inc(&lo->plh_refcount);
}
static void
pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
{
if (test_and_clear_bit(fail_bit, &lo->plh_flags))
atomic_dec(&lo->plh_refcount);
}
static void
pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
{
struct inode *inode = lo->plh_inode;
struct pnfs_layout_range range = {
.iomode = iomode,
.offset = 0,
.length = NFS4_MAX_UINT64,
};
LIST_HEAD(head);
spin_lock(&inode->i_lock);
pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
pnfs_mark_matching_lsegs_invalid(lo, &head, &range);
spin_unlock(&inode->i_lock);
pnfs_free_lseg_list(&head);
dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
iomode == IOMODE_RW ? "RW" : "READ");
}
static bool
pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
{
unsigned long start, end;
int fail_bit = pnfs_iomode_to_fail_bit(iomode);
if (test_bit(fail_bit, &lo->plh_flags) == 0)
return false;
end = jiffies;
start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
/* It is time to retry the failed layoutgets */
pnfs_layout_clear_fail_bit(lo, fail_bit);
return false;
}
return true;
}
static void
init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
{
INIT_LIST_HEAD(&lseg->pls_list);
INIT_LIST_HEAD(&lseg->pls_lc_list);
atomic_set(&lseg->pls_refcount, 1);
smp_mb();
set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
lseg->pls_layout = lo;
}
static void pnfs_free_lseg(struct pnfs_layout_segment *lseg)
{
struct inode *ino = lseg->pls_layout->plh_inode;
NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
}
static void
pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg)
{
struct inode *inode = lo->plh_inode;
WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
list_del_init(&lseg->pls_list);
/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
atomic_dec(&lo->plh_refcount);
if (list_empty(&lo->plh_segs))
clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
}
void
pnfs_put_lseg(struct pnfs_layout_segment *lseg)
{
struct pnfs_layout_hdr *lo;
struct inode *inode;
if (!lseg)
return;
dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
atomic_read(&lseg->pls_refcount),
test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
lo = lseg->pls_layout;
inode = lo->plh_inode;
if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
pnfs_get_layout_hdr(lo);
pnfs_layout_remove_lseg(lo, lseg);
spin_unlock(&inode->i_lock);
pnfs_free_lseg(lseg);
pnfs_put_layout_hdr(lo);
}
}
EXPORT_SYMBOL_GPL(pnfs_put_lseg);
static u64
end_offset(u64 start, u64 len)
{
u64 end;
end = start + len;
return end >= start ? end : NFS4_MAX_UINT64;
}
/*
* is l2 fully contained in l1?
* start1 end1
* [----------------------------------)
* start2 end2
* [----------------)
*/
static bool
pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
const 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 bool
pnfs_lseg_range_intersecting(const struct pnfs_layout_range *l1,
const 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);
}
static bool
should_free_lseg(const struct pnfs_layout_range *lseg_range,
const struct pnfs_layout_range *recall_range)
{
return (recall_range->iomode == IOMODE_ANY ||
lseg_range->iomode == recall_range->iomode) &&
pnfs_lseg_range_intersecting(lseg_range, recall_range);
}
static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
struct list_head *tmp_list)
{
if (!atomic_dec_and_test(&lseg->pls_refcount))
return false;
pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
list_add(&lseg->pls_list, tmp_list);
return true;
}
/* 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.
*/
dprintk("%s: lseg %p ref %d\n", __func__, lseg,
atomic_read(&lseg->pls_refcount));
if (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
rv = 1;
}
return rv;
}
/* Returns count of number of matching invalid lsegs remaining in list
* after call.
*/
int
pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
struct list_head *tmp_list,
struct pnfs_layout_range *recall_range)
{
struct pnfs_layout_segment *lseg, *next;
int invalid = 0, removed = 0;
dprintk("%s:Begin lo %p\n", __func__, lo);
if (list_empty(&lo->plh_segs))
return 0;
list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
if (!recall_range ||
should_free_lseg(&lseg->pls_range, recall_range)) {
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;
}
/* note free_me must contain lsegs from a single layout_hdr */
void
pnfs_free_lseg_list(struct list_head *free_me)
{
struct pnfs_layout_segment *lseg, *tmp;
if (list_empty(free_me))
return;
list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
list_del(&lseg->pls_list);
pnfs_free_lseg(lseg);
}
}
void
pnfs_destroy_layout(struct nfs_inode *nfsi)
{
struct pnfs_layout_hdr *lo;
LIST_HEAD(tmp_list);
spin_lock(&nfsi->vfs_inode.i_lock);
lo = nfsi->layout;
if (lo) {
lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
pnfs_get_layout_hdr(lo);
pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
spin_unlock(&nfsi->vfs_inode.i_lock);
pnfs_free_lseg_list(&tmp_list);
pnfs_put_layout_hdr(lo);
} else
spin_unlock(&nfsi->vfs_inode.i_lock);
}
EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
static bool
pnfs_layout_add_bulk_destroy_list(struct inode *inode,
struct list_head *layout_list)
{
struct pnfs_layout_hdr *lo;
bool ret = false;
spin_lock(&inode->i_lock);
lo = NFS_I(inode)->layout;
if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
pnfs_get_layout_hdr(lo);
list_add(&lo->plh_bulk_destroy, layout_list);
ret = true;
}
spin_unlock(&inode->i_lock);
return ret;
}
/* Caller must hold rcu_read_lock and clp->cl_lock */
static int
pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
struct nfs_server *server,
struct list_head *layout_list)
{
struct pnfs_layout_hdr *lo, *next;
struct inode *inode;
list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
inode = igrab(lo->plh_inode);
if (inode == NULL)
continue;
list_del_init(&lo->plh_layouts);
if (pnfs_layout_add_bulk_destroy_list(inode, layout_list))
continue;
rcu_read_unlock();
spin_unlock(&clp->cl_lock);
iput(inode);
spin_lock(&clp->cl_lock);
rcu_read_lock();
return -EAGAIN;
}
return 0;
}
static int
pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
bool is_bulk_recall)
{
struct pnfs_layout_hdr *lo;
struct inode *inode;
struct pnfs_layout_range range = {
.iomode = IOMODE_ANY,
.offset = 0,
.length = NFS4_MAX_UINT64,
};
LIST_HEAD(lseg_list);
int ret = 0;
while (!list_empty(layout_list)) {
lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
plh_bulk_destroy);
dprintk("%s freeing layout for inode %lu\n", __func__,
lo->plh_inode->i_ino);
inode = lo->plh_inode;
spin_lock(&inode->i_lock);
list_del_init(&lo->plh_bulk_destroy);
lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
if (is_bulk_recall)
set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
if (pnfs_mark_matching_lsegs_invalid(lo, &lseg_list, &range))
ret = -EAGAIN;
spin_unlock(&inode->i_lock);
pnfs_free_lseg_list(&lseg_list);
pnfs_put_layout_hdr(lo);
iput(inode);
}
return ret;
}
int
pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
struct nfs_fsid *fsid,
bool is_recall)
{
struct nfs_server *server;
LIST_HEAD(layout_list);
spin_lock(&clp->cl_lock);
rcu_read_lock();
restart:
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
continue;
if (pnfs_layout_bulk_destroy_byserver_locked(clp,
server,
&layout_list) != 0)
goto restart;
}
rcu_read_unlock();
spin_unlock(&clp->cl_lock);
if (list_empty(&layout_list))
return 0;
return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
}
int
pnfs_destroy_layouts_byclid(struct nfs_client *clp,
bool is_recall)
{
struct nfs_server *server;
LIST_HEAD(layout_list);
spin_lock(&clp->cl_lock);
rcu_read_lock();
restart:
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
if (pnfs_layout_bulk_destroy_byserver_locked(clp,
server,
&layout_list) != 0)
goto restart;
}
rcu_read_unlock();
spin_unlock(&clp->cl_lock);
if (list_empty(&layout_list))
return 0;
return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
}
/*
* Called by the state manger to remove all layouts established under an
* expired lease.
*/
void
pnfs_destroy_all_layouts(struct nfs_client *clp)
{
nfs4_deviceid_mark_client_invalid(clp);
nfs4_deviceid_purge_client(clp);
pnfs_destroy_layouts_byclid(clp, false);
}
/*
* Compare 2 layout stateid sequence ids, to see which is newer,
* taking into account wraparound issues.
*/
static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
{
return (s32)(s1 - s2) > 0;
}
/* update lo->plh_stateid with new if is more recent */
void
pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
bool update_barrier)
{
u32 oldseq, newseq, new_barrier;
int empty = list_empty(&lo->plh_segs);
oldseq = be32_to_cpu(lo->plh_stateid.seqid);
newseq = be32_to_cpu(new->seqid);
if (empty || pnfs_seqid_is_newer(newseq, oldseq)) {
nfs4_stateid_copy(&lo->plh_stateid, new);
if (update_barrier) {
new_barrier = be32_to_cpu(new->seqid);
} else {
/* Because of wraparound, we want to keep the barrier
* "close" to the current seqids.
*/
new_barrier = newseq - atomic_read(&lo->plh_outstanding);
}
if (empty || pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
lo->plh_barrier = new_barrier;
}
}
static bool
pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
const nfs4_stateid *stateid)
{
u32 seqid = be32_to_cpu(stateid->seqid);
return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
}
/* lget is set to 1 if called from inside send_layoutget call chain */
static bool
pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo, int lget)
{
return lo->plh_block_lgets ||
test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
(list_empty(&lo->plh_segs) &&
(atomic_read(&lo->plh_outstanding) > lget));
}
int
pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
struct nfs4_state *open_state)
{
int status = 0;
dprintk("--> %s\n", __func__);
spin_lock(&lo->plh_inode->i_lock);
if (pnfs_layoutgets_blocked(lo, 1)) {
status = -EAGAIN;
} else if (!nfs4_valid_open_stateid(open_state)) {
status = -EBADF;
} else if (list_empty(&lo->plh_segs)) {
int seq;
do {
seq = read_seqbegin(&open_state->seqlock);
nfs4_stateid_copy(dst, &open_state->stateid);
} while (read_seqretry(&open_state->seqlock, seq));
} else
nfs4_stateid_copy(dst, &lo->plh_stateid);
spin_unlock(&lo->plh_inode->i_lock);
dprintk("<-- %s\n", __func__);
return status;
}
/*
* Get layout from server.
* for now, assume that whole file layouts are requested.
* arg->offset: 0
* arg->length: all ones
*/
static struct pnfs_layout_segment *
send_layoutget(struct pnfs_layout_hdr *lo,
struct nfs_open_context *ctx,
struct pnfs_layout_range *range,
gfp_t gfp_flags)
{
struct inode *ino = lo->plh_inode;
struct nfs_server *server = NFS_SERVER(ino);
struct nfs4_layoutget *lgp;
struct pnfs_layout_segment *lseg;
dprintk("--> %s\n", __func__);
lgp = kzalloc(sizeof(*lgp), gfp_flags);
if (lgp == NULL)
return NULL;
lgp->args.minlength = PAGE_CACHE_SIZE;
if (lgp->args.minlength > range->length)
lgp->args.minlength = range->length;
lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
lgp->args.range = *range;
lgp->args.type = server->pnfs_curr_ld->id;
lgp->args.inode = ino;
lgp->args.ctx = get_nfs_open_context(ctx);
lgp->gfp_flags = gfp_flags;
lgp->cred = lo->plh_lc_cred;
/* Synchronously retrieve layout information from server and
* store in lseg.
*/
lseg = nfs4_proc_layoutget(lgp, gfp_flags);
if (IS_ERR(lseg)) {
switch (PTR_ERR(lseg)) {
case -ENOMEM:
case -ERESTARTSYS:
break;
default:
/* remember that LAYOUTGET failed and suspend trying */
pnfs_layout_io_set_failed(lo, range->iomode);
}
return NULL;
}
return lseg;
}
static void pnfs_clear_layoutcommit(struct inode *inode,
struct list_head *head)
{
struct nfs_inode *nfsi = NFS_I(inode);
struct pnfs_layout_segment *lseg, *tmp;
if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
return;
list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
continue;
pnfs_lseg_dec_and_remove_zero(lseg, head);
}
}
/*
* Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
* when the layout segment list is empty.
*
* Note that a pnfs_layout_hdr can exist with an empty layout segment
* list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
* deviceid is marked invalid.
*/
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, empty;
dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
spin_lock(&ino->i_lock);
lo = nfsi->layout;
if (!lo) {
spin_unlock(&ino->i_lock);
dprintk("NFS: %s no layout to return\n", __func__);
goto out;
}
stateid = nfsi->layout->plh_stateid;
/* Reference matched in nfs4_layoutreturn_release */
pnfs_get_layout_hdr(lo);
empty = list_empty(&lo->plh_segs);
pnfs_clear_layoutcommit(ino, &tmp_list);
pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
/* Don't send a LAYOUTRETURN if list was initially empty */
if (empty) {
spin_unlock(&ino->i_lock);
pnfs_put_layout_hdr(lo);
dprintk("NFS: %s no layout segments to return\n", __func__);
goto out;
}
lo->plh_block_lgets++;
spin_unlock(&ino->i_lock);
pnfs_free_lseg_list(&tmp_list);
lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
if (unlikely(lrp == NULL)) {
status = -ENOMEM;
spin_lock(&ino->i_lock);
lo->plh_block_lgets--;
spin_unlock(&ino->i_lock);
pnfs_put_layout_hdr(lo);
goto out;
}
lrp->args.stateid = stateid;
lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
lrp->args.inode = ino;
lrp->args.layout = lo;
lrp->clp = NFS_SERVER(ino)->nfs_client;
lrp->cred = lo->plh_lc_cred;
status = nfs4_proc_layoutreturn(lrp);
out:
dprintk("<-- %s status: %d\n", __func__, status);
return status;
}
EXPORT_SYMBOL_GPL(_pnfs_return_layout);
int
pnfs_commit_and_return_layout(struct inode *inode)
{
struct pnfs_layout_hdr *lo;
int ret;
spin_lock(&inode->i_lock);
lo = NFS_I(inode)->layout;
if (lo == NULL) {
spin_unlock(&inode->i_lock);
return 0;
}
pnfs_get_layout_hdr(lo);
/* Block new layoutgets and read/write to ds */
lo->plh_block_lgets++;
spin_unlock(&inode->i_lock);
filemap_fdatawait(inode->i_mapping);
ret = pnfs_layoutcommit_inode(inode, true);
if (ret == 0)
ret = _pnfs_return_layout(inode);
spin_lock(&inode->i_lock);
lo->plh_block_lgets--;
spin_unlock(&inode->i_lock);
pnfs_put_layout_hdr(lo);
return ret;
}
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++;
pnfs_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--;
if (atomic_dec_and_test(&lo->plh_refcount)) {
pnfs_detach_layout_hdr(lo);
spin_unlock(&ino->i_lock);
pnfs_free_layout_hdr(lo);
} else
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 (pnfs_seqid_is_newer(barrier, lo->plh_barrier))
lo->plh_barrier = barrier;
spin_unlock(&ino->i_lock);
}
bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
{
struct nfs_inode *nfsi = NFS_I(ino);
struct pnfs_layout_hdr *lo;
struct pnfs_layout_segment *lseg;
u32 current_seqid;
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)) {
rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
found = true;
goto out;
}
lo = nfsi->layout;
current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
/* 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);
out:
spin_unlock(&ino->i_lock);
return found;
}
/*
* 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
pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
const struct pnfs_layout_range *l2)
{
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;
/* read > read/write */
return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
}
static void
pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg)
{
struct pnfs_layout_segment *lp;
dprintk("%s:Begin\n", __func__);
list_for_each_entry(lp, &lo->plh_segs, pls_list) {
if (pnfs_lseg_range_cmp(&lseg->pls_range, &lp->pls_range) > 0)
continue;
list_add_tail(&lseg->pls_list, &lp->pls_list);
dprintk("%s: inserted lseg %p "
"iomode %d offset %llu length %llu before "
"lp %p iomode %d offset %llu length %llu\n",
__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);
goto out;
}
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:
pnfs_get_layout_hdr(lo);
dprintk("%s:Return\n", __func__);
}
static struct pnfs_layout_hdr *
alloc_init_layout_hdr(struct inode *ino,
struct nfs_open_context *ctx,
gfp_t gfp_flags)
{
struct pnfs_layout_hdr *lo;
lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
if (!lo)
return NULL;
atomic_set(&lo->plh_refcount, 1);
INIT_LIST_HEAD(&lo->plh_layouts);
INIT_LIST_HEAD(&lo->plh_segs);
INIT_LIST_HEAD(&lo->plh_bulk_destroy);
lo->plh_inode = ino;
lo->plh_lc_cred = get_rpccred(ctx->cred);
return lo;
}
static struct pnfs_layout_hdr *
pnfs_find_alloc_layout(struct inode *ino,
struct nfs_open_context *ctx,
gfp_t gfp_flags)
{
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);
if (nfsi->layout != NULL)
goto out_existing;
spin_unlock(&ino->i_lock);
new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
spin_lock(&ino->i_lock);
if (likely(nfsi->layout == NULL)) { /* Won the race? */
nfsi->layout = new;
return new;
} else if (new != NULL)
pnfs_free_layout_hdr(new);
out_existing:
pnfs_get_layout_hdr(nfsi->layout);
return nfsi->layout;
}
/*
* 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 bool
pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
const struct pnfs_layout_range *range)
{
struct pnfs_layout_range range1;
if ((range->iomode == IOMODE_RW &&
ls_range->iomode != IOMODE_RW) ||
!pnfs_lseg_range_intersecting(ls_range, range))
return 0;
/* range1 covers only the first byte in the range */
range1 = *range;
range1.length = 1;
return pnfs_lseg_range_contained(ls_range, &range1);
}
/*
* lookup range in layout
*/
static struct pnfs_layout_segment *
pnfs_find_lseg(struct pnfs_layout_hdr *lo,
struct pnfs_layout_range *range)
{
struct pnfs_layout_segment *lseg, *ret = NULL;
dprintk("%s:Begin\n", __func__);
list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
pnfs_lseg_range_match(&lseg->pls_range, range)) {
ret = pnfs_get_lseg(lseg);
break;
}
if (lseg->pls_range.offset > range->offset)
break;
}
dprintk("%s:Return lseg %p ref %d\n",
__func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
return ret;
}
/*
* Use mdsthreshold hints set at each OPEN to determine if I/O should go
* to the MDS or over pNFS
*
* The nfs_inode read_io and write_io fields are cumulative counters reset
* when there are no layout segments. Note that in pnfs_update_layout iomode
* is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
* WRITE request.
*
* A return of true means use MDS I/O.
*
* From rfc 5661:
* If a file's size is smaller than the file size threshold, data accesses
* SHOULD be sent to the metadata server. If an I/O request has a length that
* is below the I/O size threshold, the I/O SHOULD be sent to the metadata
* server. If both file size and I/O size are provided, the client SHOULD
* reach or exceed both thresholds before sending its read or write
* requests to the data server.
*/
static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
struct inode *ino, int iomode)
{
struct nfs4_threshold *t = ctx->mdsthreshold;
struct nfs_inode *nfsi = NFS_I(ino);
loff_t fsize = i_size_read(ino);
bool size = false, size_set = false, io = false, io_set = false, ret = false;
if (t == NULL)
return ret;
dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
__func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
switch (iomode) {
case IOMODE_READ:
if (t->bm & THRESHOLD_RD) {
dprintk("%s fsize %llu\n", __func__, fsize);
size_set = true;
if (fsize < t->rd_sz)
size = true;
}
if (t->bm & THRESHOLD_RD_IO) {
dprintk("%s nfsi->read_io %llu\n", __func__,
nfsi->read_io);
io_set = true;
if (nfsi->read_io < t->rd_io_sz)
io = true;
}
break;
case IOMODE_RW:
if (t->bm & THRESHOLD_WR) {
dprintk("%s fsize %llu\n", __func__, fsize);
size_set = true;
if (fsize < t->wr_sz)
size = true;
}
if (t->bm & THRESHOLD_WR_IO) {
dprintk("%s nfsi->write_io %llu\n", __func__,
nfsi->write_io);
io_set = true;
if (nfsi->write_io < t->wr_io_sz)
io = true;
}
break;
}
if (size_set && io_set) {
if (size && io)
ret = true;
} else if (size || io)
ret = true;
dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
return ret;
}
/*
* Layout segment is retreived from the server if not cached.
* The appropriate layout segment is referenced and returned to the caller.
*/
struct pnfs_layout_segment *
pnfs_update_layout(struct inode *ino,
struct nfs_open_context *ctx,
loff_t pos,
u64 count,
enum pnfs_iomode iomode,
gfp_t gfp_flags)
{
struct pnfs_layout_range arg = {
.iomode = iomode,
.offset = pos,
.length = count,
};
unsigned pg_offset;
struct nfs_server *server = NFS_SERVER(ino);
struct nfs_client *clp = server->nfs_client;
struct pnfs_layout_hdr *lo;
struct pnfs_layout_segment *lseg = NULL;
bool first;
if (!pnfs_enabled_sb(NFS_SERVER(ino)))
goto out;
if (pnfs_within_mdsthreshold(ctx, ino, iomode))
goto out;
spin_lock(&ino->i_lock);
lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
if (lo == NULL) {
spin_unlock(&ino->i_lock);
goto out;
}
/* Do we even need to bother with this? */
if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
dprintk("%s matches recall, use MDS\n", __func__);
goto out_unlock;
}
/* if LAYOUTGET already failed once we don't try again */
if (pnfs_layout_io_test_failed(lo, iomode))
goto out_unlock;
/* Check to see if the layout for the given range already exists */
lseg = pnfs_find_lseg(lo, &arg);
if (lseg)
goto out_unlock;
if (pnfs_layoutgets_blocked(lo, 0))
goto out_unlock;
atomic_inc(&lo->plh_outstanding);
first = list_empty(&lo->plh_layouts) ? true : false;
spin_unlock(&ino->i_lock);
if (first) {
/* 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);
list_add_tail(&lo->plh_layouts, &server->layouts);
spin_unlock(&clp->cl_lock);
}
pg_offset = arg.offset & ~PAGE_CACHE_MASK;
if (pg_offset) {
arg.offset -= pg_offset;
arg.length += pg_offset;
}
if (arg.length != NFS4_MAX_UINT64)
arg.length = PAGE_CACHE_ALIGN(arg.length);
lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
atomic_dec(&lo->plh_outstanding);
out_put_layout_hdr:
pnfs_put_layout_hdr(lo);
out:
dprintk("%s: inode %s/%llu pNFS layout segment %s for "
"(%s, offset: %llu, length: %llu)\n",
__func__, ino->i_sb->s_id,
(unsigned long long)NFS_FILEID(ino),
lseg == NULL ? "not found" : "found",
iomode==IOMODE_RW ? "read/write" : "read-only",
(unsigned long long)pos,
(unsigned long long)count);
return lseg;
out_unlock:
spin_unlock(&ino->i_lock);
goto out_put_layout_hdr;
}
EXPORT_SYMBOL_GPL(pnfs_update_layout);
struct pnfs_layout_segment *
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;
struct inode *ino = lo->plh_inode;
int status = 0;
/* Inject layout blob into I/O device driver */
lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
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);
if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
dprintk("%s forget reply due to recall\n", __func__);
goto out_forget_reply;
}
if (pnfs_layoutgets_blocked(lo, 1) ||
pnfs_layout_stateid_blocked(lo, &res->stateid)) {
dprintk("%s forget reply due to state\n", __func__);
goto out_forget_reply;
}
/* Done processing layoutget. Set the layout stateid */
pnfs_set_layout_stateid(lo, &res->stateid, false);
init_lseg(lo, lseg);
lseg->pls_range = res->range;
pnfs_get_lseg(lseg);
pnfs_layout_insert_lseg(lo, lseg);
if (res->return_on_close) {
set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
}
spin_unlock(&ino->i_lock);
return lseg;
out:
return ERR_PTR(status);
out_forget_reply:
spin_unlock(&ino->i_lock);
lseg->pls_layout = lo;
NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
goto out;
}
void
pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
u64 rd_size = req->wb_bytes;
WARN_ON_ONCE(pgio->pg_lseg != NULL);
if (req->wb_offset != req->wb_pgbase) {
nfs_pageio_reset_read_mds(pgio);
return;
}
if (pgio->pg_dreq == NULL)
rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
else
rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
req_offset(req),
rd_size,
IOMODE_READ,
GFP_KERNEL);
/* If no lseg, fall back to read through mds */
if (pgio->pg_lseg == NULL)
nfs_pageio_reset_read_mds(pgio);
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
void
pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio,
struct nfs_page *req, u64 wb_size)
{
WARN_ON_ONCE(pgio->pg_lseg != NULL);
if (req->wb_offset != req->wb_pgbase) {
nfs_pageio_reset_write_mds(pgio);
return;
}
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
req_offset(req),
wb_size,
IOMODE_RW,
GFP_NOFS);
/* If no lseg, fall back to write through mds */
if (pgio->pg_lseg == NULL)
nfs_pageio_reset_write_mds(pgio);
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
void
pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode,
const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_server *server = NFS_SERVER(inode);
struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
if (ld == NULL)
nfs_pageio_init_read(pgio, inode, compl_ops);
else
nfs_pageio_init(pgio, inode, ld->pg_read_ops, compl_ops, server->rsize, 0);
}
void
pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode,
int ioflags,
const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_server *server = NFS_SERVER(inode);
struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
if (ld == NULL)
nfs_pageio_init_write(pgio, inode, ioflags, compl_ops);
else
nfs_pageio_init(pgio, inode, ld->pg_write_ops, compl_ops, server->wsize, ioflags);
}
bool
pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
if (pgio->pg_lseg == NULL)
return nfs_generic_pg_test(pgio, prev, req);
/*
* 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);
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
int pnfs_write_done_resend_to_mds(struct inode *inode,
struct list_head *head,
const struct nfs_pgio_completion_ops *compl_ops,
struct nfs_direct_req *dreq)
{
struct nfs_pageio_descriptor pgio;
LIST_HEAD(failed);
/* Resend all requests through the MDS */
nfs_pageio_init_write(&pgio, inode, FLUSH_STABLE, compl_ops);
pgio.pg_dreq = dreq;
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;
}
EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
static void pnfs_ld_handle_write_error(struct nfs_write_data *data)
{
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 &
PNFS_LAYOUTRET_ON_ERROR) {
pnfs_return_layout(hdr->inode);
}
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
data->task.tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
&hdr->pages,
hdr->completion_ops,
hdr->dreq);
}
/*
* Called by non rpc-based layout drivers
*/
void pnfs_ld_write_done(struct nfs_write_data *data)
{
struct nfs_pgio_header *hdr = data->header;
trace_nfs4_pnfs_write(data, hdr->pnfs_error);
if (!hdr->pnfs_error) {
pnfs_set_layoutcommit(data);
hdr->mds_ops->rpc_call_done(&data->task, data);
} else
pnfs_ld_handle_write_error(data);
hdr->mds_ops->rpc_release(data);
}
EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
static void
pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_write_data *data)
{
struct nfs_pgio_header *hdr = data->header;
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;
}
nfs_writedata_release(data);
}
static enum pnfs_try_status
pnfs_try_to_write_data(struct nfs_write_data *wdata,
const struct rpc_call_ops *call_ops,
struct pnfs_layout_segment *lseg,
int how)
{
struct nfs_pgio_header *hdr = wdata->header;
struct inode *inode = hdr->inode;
enum pnfs_try_status trypnfs;
struct nfs_server *nfss = NFS_SERVER(inode);
hdr->mds_ops = call_ops;
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);
if (trypnfs != PNFS_NOT_ATTEMPTED)
nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
return trypnfs;
}
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;
data = list_first_entry(head, struct nfs_write_data, list);
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);
}
pnfs_put_lseg(lseg);
}
static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
{
pnfs_put_lseg(hdr->lseg);
nfs_writehdr_free(hdr);
}
EXPORT_SYMBOL_GPL(pnfs_writehdr_free);
int
pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
{
struct nfs_write_header *whdr;
struct nfs_pgio_header *hdr;
int ret;
whdr = nfs_writehdr_alloc();
if (!whdr) {
desc->pg_completion_ops->error_cleanup(&desc->pg_list);
pnfs_put_lseg(desc->pg_lseg);
desc->pg_lseg = NULL;
return -ENOMEM;
}
hdr = &whdr->header;
nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
atomic_inc(&hdr->refcnt);
ret = nfs_generic_flush(desc, hdr);
if (ret != 0) {
pnfs_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))
hdr->completion_ops->completion(hdr);
return ret;
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
int pnfs_read_done_resend_to_mds(struct inode *inode,
struct list_head *head,
const struct nfs_pgio_completion_ops *compl_ops,
struct nfs_direct_req *dreq)
{
struct nfs_pageio_descriptor pgio;
LIST_HEAD(failed);
/* Resend all requests through the MDS */
nfs_pageio_init_read(&pgio, inode, compl_ops);
pgio.pg_dreq = dreq;
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)) {
list_move(&failed, head);
return -EIO;
}
return 0;
}
EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
{
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 &
PNFS_LAYOUTRET_ON_ERROR) {
pnfs_return_layout(hdr->inode);
}
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
data->task.tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
&hdr->pages,
hdr->completion_ops,
hdr->dreq);
}
/*
* Called by non rpc-based layout drivers
*/
void pnfs_ld_read_done(struct nfs_read_data *data)
{
struct nfs_pgio_header *hdr = data->header;
trace_nfs4_pnfs_read(data, hdr->pnfs_error);
if (likely(!hdr->pnfs_error)) {
__nfs4_read_done_cb(data);
hdr->mds_ops->rpc_call_done(&data->task, data);
} else
pnfs_ld_handle_read_error(data);
hdr->mds_ops->rpc_release(data);
}
EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
static void
pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_read_data *data)
{
struct nfs_pgio_header *hdr = data->header;
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;
}
nfs_readdata_release(data);
}
/*
* Call the appropriate parallel I/O subsystem read function.
*/
static enum pnfs_try_status
pnfs_try_to_read_data(struct nfs_read_data *rdata,
const struct rpc_call_ops *call_ops,
struct pnfs_layout_segment *lseg)
{
struct nfs_pgio_header *hdr = rdata->header;
struct inode *inode = hdr->inode;
struct nfs_server *nfss = NFS_SERVER(inode);
enum pnfs_try_status trypnfs;
hdr->mds_ops = call_ops;
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);
if (trypnfs != PNFS_NOT_ATTEMPTED)
nfs_inc_stats(inode, NFSIOS_PNFS_READ);
dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
return trypnfs;
}
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;
data = list_first_entry(head, struct nfs_read_data, list);
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);
}
pnfs_put_lseg(lseg);
}
static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
{
pnfs_put_lseg(hdr->lseg);
nfs_readhdr_free(hdr);
}
EXPORT_SYMBOL_GPL(pnfs_readhdr_free);
int
pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
{
struct nfs_read_header *rhdr;
struct nfs_pgio_header *hdr;
int ret;
rhdr = nfs_readhdr_alloc();
if (!rhdr) {
desc->pg_completion_ops->error_cleanup(&desc->pg_list);
ret = -ENOMEM;
pnfs_put_lseg(desc->pg_lseg);
desc->pg_lseg = NULL;
return ret;
}
hdr = &rhdr->header;
nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
atomic_inc(&hdr->refcnt);
ret = nfs_generic_pagein(desc, hdr);
if (ret != 0) {
pnfs_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))
hdr->completion_ops->completion(hdr);
return ret;
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
static void pnfs_clear_layoutcommitting(struct inode *inode)
{
unsigned long *bitlock = &NFS_I(inode)->flags;
clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
smp_mb__after_clear_bit();
wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
}
/*
* There can be multiple RW segments.
*/
static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
{
struct pnfs_layout_segment *lseg;
list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
if (lseg->pls_range.iomode == IOMODE_RW &&
test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
list_add(&lseg->pls_lc_list, listp);
}
}
static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
{
struct pnfs_layout_segment *lseg, *tmp;
/* Matched by references in pnfs_set_layoutcommit */
list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
list_del_init(&lseg->pls_lc_list);
pnfs_put_lseg(lseg);
}
pnfs_clear_layoutcommitting(inode);
}
void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
{
pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
}
EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
void
pnfs_set_layoutcommit(struct nfs_write_data *wdata)
{
struct nfs_pgio_header *hdr = wdata->header;
struct inode *inode = hdr->inode;
struct nfs_inode *nfsi = NFS_I(inode);
loff_t end_pos = wdata->mds_offset + wdata->res.count;
bool mark_as_dirty = false;
spin_lock(&inode->i_lock);
if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
mark_as_dirty = true;
dprintk("%s: Set layoutcommit for inode %lu ",
__func__, inode->i_ino);
}
if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
/* references matched in nfs4_layoutcommit_release */
pnfs_get_lseg(hdr->lseg);
}
if (end_pos > nfsi->layout->plh_lwb)
nfsi->layout->plh_lwb = end_pos;
spin_unlock(&inode->i_lock);
dprintk("%s: lseg %p end_pos %llu\n",
__func__, hdr->lseg, nfsi->layout->plh_lwb);
/* 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)
mark_inode_dirty_sync(inode);
}
EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
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);
pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
}
/*
* 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.
*/
int
pnfs_layoutcommit_inode(struct inode *inode, bool sync)
{
struct nfs4_layoutcommit_data *data;
struct nfs_inode *nfsi = NFS_I(inode);
loff_t end_pos;
int status;
if (!pnfs_layoutcommit_outstanding(inode))
return 0;
dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
status = -EAGAIN;
if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
if (!sync)
goto out;
status = wait_on_bit_lock(&nfsi->flags,
NFS_INO_LAYOUTCOMMITTING,
nfs_wait_bit_killable,
TASK_KILLABLE);
if (status)
goto out;
}
status = -ENOMEM;
/* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
data = kzalloc(sizeof(*data), GFP_NOFS);
if (!data)
goto clear_layoutcommitting;
status = 0;
spin_lock(&inode->i_lock);
if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
goto out_unlock;
INIT_LIST_HEAD(&data->lseg_list);
pnfs_list_write_lseg(inode, &data->lseg_list);
end_pos = nfsi->layout->plh_lwb;
nfsi->layout->plh_lwb = 0;
nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
spin_unlock(&inode->i_lock);
data->args.inode = inode;
data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
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:
if (status)
mark_inode_dirty_sync(inode);
dprintk("<-- %s status %d\n", __func__, status);
return status;
out_unlock:
spin_unlock(&inode->i_lock);
kfree(data);
clear_layoutcommitting:
pnfs_clear_layoutcommitting(inode);
goto out;
}
struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
{
struct nfs4_threshold *thp;
thp = kzalloc(sizeof(*thp), GFP_NOFS);
if (!thp) {
dprintk("%s mdsthreshold allocation failed\n", __func__);
return NULL;
}
return thp;
}
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