blob: a51534c71b3693a5571ce898aad35ddebf1eaee7 [file] [log] [blame]
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_inode.h"
#include "xfs_dinode.h"
#include "xfs_error.h"
#include "xfs_mru_cache.h"
#include "xfs_filestream.h"
#include "xfs_vnodeops.h"
#include "xfs_utils.h"
#include "xfs_buf_item.h"
#include "xfs_inode_item.h"
#include "xfs_rw.h"
#include <linux/kthread.h>
#include <linux/freezer.h>
/*
* xfs_sync flushes any pending I/O to file system vfsp.
*
* This routine is called by vfs_sync() to make sure that things make it
* out to disk eventually, on sync() system calls to flush out everything,
* and when the file system is unmounted. For the vfs_sync() case, all
* we really need to do is sync out the log to make all of our meta-data
* updates permanent (except for timestamps). For calls from pflushd(),
* dirty pages are kept moving by calling pdflush() on the inodes
* containing them. We also flush the inodes that we can lock without
* sleeping and the superblock if we can lock it without sleeping from
* vfs_sync() so that items at the tail of the log are always moving out.
*
* Flags:
* SYNC_BDFLUSH - We're being called from vfs_sync() so we don't want
* to sleep if we can help it. All we really need
* to do is ensure that the log is synced at least
* periodically. We also push the inodes and
* superblock if we can lock them without sleeping
* and they are not pinned.
* SYNC_ATTR - We need to flush the inodes. If SYNC_BDFLUSH is not
* set, then we really want to lock each inode and flush
* it.
* SYNC_WAIT - All the flushes that take place in this call should
* be synchronous.
* SYNC_DELWRI - This tells us to push dirty pages associated with
* inodes. SYNC_WAIT and SYNC_BDFLUSH are used to
* determine if they should be flushed sync, async, or
* delwri.
* SYNC_CLOSE - This flag is passed when the system is being
* unmounted. We should sync and invalidate everything.
* SYNC_FSDATA - This indicates that the caller would like to make
* sure the superblock is safe on disk. We can ensure
* this by simply making sure the log gets flushed
* if SYNC_BDFLUSH is set, and by actually writing it
* out otherwise.
* SYNC_IOWAIT - The caller wants us to wait for all data I/O to complete
* before we return (including direct I/O). Forms the drain
* side of the write barrier needed to safely quiesce the
* filesystem.
*
*/
int
xfs_sync(
xfs_mount_t *mp,
int flags)
{
int error;
/*
* Get the Quota Manager to flush the dquots.
*
* If XFS quota support is not enabled or this filesystem
* instance does not use quotas XFS_QM_DQSYNC will always
* return zero.
*/
error = XFS_QM_DQSYNC(mp, flags);
if (error) {
/*
* If we got an IO error, we will be shutting down.
* So, there's nothing more for us to do here.
*/
ASSERT(error != EIO || XFS_FORCED_SHUTDOWN(mp));
if (XFS_FORCED_SHUTDOWN(mp))
return XFS_ERROR(error);
}
if (flags & SYNC_IOWAIT)
xfs_filestream_flush(mp);
return xfs_syncsub(mp, flags, NULL);
}
/*
* xfs sync routine for internal use
*
* This routine supports all of the flags defined for the generic vfs_sync
* interface as explained above under xfs_sync.
*
*/
int
xfs_sync_inodes(
xfs_mount_t *mp,
int flags,
int *bypassed)
{
xfs_inode_t *ip = NULL;
struct inode *vp = NULL;
int error;
int last_error;
uint64_t fflag;
uint lock_flags;
uint base_lock_flags;
boolean_t mount_locked;
boolean_t vnode_refed;
int preempt;
xfs_iptr_t *ipointer;
#ifdef DEBUG
boolean_t ipointer_in = B_FALSE;
#define IPOINTER_SET ipointer_in = B_TRUE
#define IPOINTER_CLR ipointer_in = B_FALSE
#else
#define IPOINTER_SET
#define IPOINTER_CLR
#endif
/* Insert a marker record into the inode list after inode ip. The list
* must be locked when this is called. After the call the list will no
* longer be locked.
*/
#define IPOINTER_INSERT(ip, mp) { \
ASSERT(ipointer_in == B_FALSE); \
ipointer->ip_mnext = ip->i_mnext; \
ipointer->ip_mprev = ip; \
ip->i_mnext = (xfs_inode_t *)ipointer; \
ipointer->ip_mnext->i_mprev = (xfs_inode_t *)ipointer; \
preempt = 0; \
XFS_MOUNT_IUNLOCK(mp); \
mount_locked = B_FALSE; \
IPOINTER_SET; \
}
/* Remove the marker from the inode list. If the marker was the only item
* in the list then there are no remaining inodes and we should zero out
* the whole list. If we are the current head of the list then move the head
* past us.
*/
#define IPOINTER_REMOVE(ip, mp) { \
ASSERT(ipointer_in == B_TRUE); \
if (ipointer->ip_mnext != (xfs_inode_t *)ipointer) { \
ip = ipointer->ip_mnext; \
ip->i_mprev = ipointer->ip_mprev; \
ipointer->ip_mprev->i_mnext = ip; \
if (mp->m_inodes == (xfs_inode_t *)ipointer) { \
mp->m_inodes = ip; \
} \
} else { \
ASSERT(mp->m_inodes == (xfs_inode_t *)ipointer); \
mp->m_inodes = NULL; \
ip = NULL; \
} \
IPOINTER_CLR; \
}
#define XFS_PREEMPT_MASK 0x7f
ASSERT(!(flags & SYNC_BDFLUSH));
if (bypassed)
*bypassed = 0;
if (mp->m_flags & XFS_MOUNT_RDONLY)
return 0;
error = 0;
last_error = 0;
preempt = 0;
/* Allocate a reference marker */
ipointer = (xfs_iptr_t *)kmem_zalloc(sizeof(xfs_iptr_t), KM_SLEEP);
fflag = XFS_B_ASYNC; /* default is don't wait */
if (flags & SYNC_DELWRI)
fflag = XFS_B_DELWRI;
if (flags & SYNC_WAIT)
fflag = 0; /* synchronous overrides all */
base_lock_flags = XFS_ILOCK_SHARED;
if (flags & (SYNC_DELWRI | SYNC_CLOSE)) {
/*
* We need the I/O lock if we're going to call any of
* the flush/inval routines.
*/
base_lock_flags |= XFS_IOLOCK_SHARED;
}
XFS_MOUNT_ILOCK(mp);
ip = mp->m_inodes;
mount_locked = B_TRUE;
vnode_refed = B_FALSE;
IPOINTER_CLR;
do {
ASSERT(ipointer_in == B_FALSE);
ASSERT(vnode_refed == B_FALSE);
lock_flags = base_lock_flags;
/*
* There were no inodes in the list, just break out
* of the loop.
*/
if (ip == NULL) {
break;
}
/*
* We found another sync thread marker - skip it
*/
if (ip->i_mount == NULL) {
ip = ip->i_mnext;
continue;
}
vp = VFS_I(ip);
/*
* If the vnode is gone then this is being torn down,
* call reclaim if it is flushed, else let regular flush
* code deal with it later in the loop.
*/
if (vp == NULL) {
/* Skip ones already in reclaim */
if (ip->i_flags & XFS_IRECLAIM) {
ip = ip->i_mnext;
continue;
}
if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL) == 0) {
ip = ip->i_mnext;
} else if ((xfs_ipincount(ip) == 0) &&
xfs_iflock_nowait(ip)) {
IPOINTER_INSERT(ip, mp);
xfs_finish_reclaim(ip, 1,
XFS_IFLUSH_DELWRI_ELSE_ASYNC);
XFS_MOUNT_ILOCK(mp);
mount_locked = B_TRUE;
IPOINTER_REMOVE(ip, mp);
} else {
xfs_iunlock(ip, XFS_ILOCK_EXCL);
ip = ip->i_mnext;
}
continue;
}
if (VN_BAD(vp)) {
ip = ip->i_mnext;
continue;
}
if (XFS_FORCED_SHUTDOWN(mp) && !(flags & SYNC_CLOSE)) {
XFS_MOUNT_IUNLOCK(mp);
kmem_free(ipointer);
return 0;
}
/*
* Try to lock without sleeping. We're out of order with
* the inode list lock here, so if we fail we need to drop
* the mount lock and try again. If we're called from
* bdflush() here, then don't bother.
*
* The inode lock here actually coordinates with the
* almost spurious inode lock in xfs_ireclaim() to prevent
* the vnode we handle here without a reference from
* being freed while we reference it. If we lock the inode
* while it's on the mount list here, then the spurious inode
* lock in xfs_ireclaim() after the inode is pulled from
* the mount list will sleep until we release it here.
* This keeps the vnode from being freed while we reference
* it.
*/
if (xfs_ilock_nowait(ip, lock_flags) == 0) {
if (vp == NULL) {
ip = ip->i_mnext;
continue;
}
vp = vn_grab(vp);
if (vp == NULL) {
ip = ip->i_mnext;
continue;
}
IPOINTER_INSERT(ip, mp);
xfs_ilock(ip, lock_flags);
ASSERT(vp == VFS_I(ip));
ASSERT(ip->i_mount == mp);
vnode_refed = B_TRUE;
}
/* From here on in the loop we may have a marker record
* in the inode list.
*/
/*
* If we have to flush data or wait for I/O completion
* we need to drop the ilock that we currently hold.
* If we need to drop the lock, insert a marker if we
* have not already done so.
*/
if ((flags & (SYNC_CLOSE|SYNC_IOWAIT)) ||
((flags & SYNC_DELWRI) && VN_DIRTY(vp))) {
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (flags & SYNC_CLOSE) {
/* Shutdown case. Flush and invalidate. */
if (XFS_FORCED_SHUTDOWN(mp))
xfs_tosspages(ip, 0, -1,
FI_REMAPF);
else
error = xfs_flushinval_pages(ip,
0, -1, FI_REMAPF);
} else if ((flags & SYNC_DELWRI) && VN_DIRTY(vp)) {
error = xfs_flush_pages(ip, 0,
-1, fflag, FI_NONE);
}
/*
* When freezing, we need to wait ensure all I/O (including direct
* I/O) is complete to ensure no further data modification can take
* place after this point
*/
if (flags & SYNC_IOWAIT)
vn_iowait(ip);
xfs_ilock(ip, XFS_ILOCK_SHARED);
}
if ((flags & SYNC_ATTR) &&
(ip->i_update_core ||
(ip->i_itemp && ip->i_itemp->ili_format.ilf_fields))) {
if (mount_locked)
IPOINTER_INSERT(ip, mp);
if (flags & SYNC_WAIT) {
xfs_iflock(ip);
error = xfs_iflush(ip, XFS_IFLUSH_SYNC);
/*
* If we can't acquire the flush lock, then the inode
* is already being flushed so don't bother waiting.
*
* If we can lock it then do a delwri flush so we can
* combine multiple inode flushes in each disk write.
*/
} else if (xfs_iflock_nowait(ip)) {
error = xfs_iflush(ip, XFS_IFLUSH_DELWRI);
} else if (bypassed) {
(*bypassed)++;
}
}
if (lock_flags != 0) {
xfs_iunlock(ip, lock_flags);
}
if (vnode_refed) {
/*
* If we had to take a reference on the vnode
* above, then wait until after we've unlocked
* the inode to release the reference. This is
* because we can be already holding the inode
* lock when IRELE() calls xfs_inactive().
*
* Make sure to drop the mount lock before calling
* IRELE() so that we don't trip over ourselves if
* we have to go for the mount lock again in the
* inactive code.
*/
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
IRELE(ip);
vnode_refed = B_FALSE;
}
if (error) {
last_error = error;
}
/*
* bail out if the filesystem is corrupted.
*/
if (error == EFSCORRUPTED) {
if (!mount_locked) {
XFS_MOUNT_ILOCK(mp);
IPOINTER_REMOVE(ip, mp);
}
XFS_MOUNT_IUNLOCK(mp);
ASSERT(ipointer_in == B_FALSE);
kmem_free(ipointer);
return XFS_ERROR(error);
}
/* Let other threads have a chance at the mount lock
* if we have looped many times without dropping the
* lock.
*/
if ((++preempt & XFS_PREEMPT_MASK) == 0) {
if (mount_locked) {
IPOINTER_INSERT(ip, mp);
}
}
if (mount_locked == B_FALSE) {
XFS_MOUNT_ILOCK(mp);
mount_locked = B_TRUE;
IPOINTER_REMOVE(ip, mp);
continue;
}
ASSERT(ipointer_in == B_FALSE);
ip = ip->i_mnext;
} while (ip != mp->m_inodes);
XFS_MOUNT_IUNLOCK(mp);
ASSERT(ipointer_in == B_FALSE);
kmem_free(ipointer);
return XFS_ERROR(last_error);
}
/*
* xfs sync routine for internal use
*
* This routine supports all of the flags defined for the generic vfs_sync
* interface as explained above under xfs_sync.
*
*/
int
xfs_syncsub(
xfs_mount_t *mp,
int flags,
int *bypassed)
{
int error = 0;
int last_error = 0;
uint log_flags = XFS_LOG_FORCE;
xfs_buf_t *bp;
xfs_buf_log_item_t *bip;
/*
* Sync out the log. This ensures that the log is periodically
* flushed even if there is not enough activity to fill it up.
*/
if (flags & SYNC_WAIT)
log_flags |= XFS_LOG_SYNC;
xfs_log_force(mp, (xfs_lsn_t)0, log_flags);
if (flags & (SYNC_ATTR|SYNC_DELWRI)) {
if (flags & SYNC_BDFLUSH)
xfs_finish_reclaim_all(mp, 1);
else
error = xfs_sync_inodes(mp, flags, bypassed);
}
/*
* Flushing out dirty data above probably generated more
* log activity, so if this isn't vfs_sync() then flush
* the log again.
*/
if (flags & SYNC_DELWRI) {
xfs_log_force(mp, (xfs_lsn_t)0, log_flags);
}
if (flags & SYNC_FSDATA) {
/*
* If this is vfs_sync() then only sync the superblock
* if we can lock it without sleeping and it is not pinned.
*/
if (flags & SYNC_BDFLUSH) {
bp = xfs_getsb(mp, XFS_BUF_TRYLOCK);
if (bp != NULL) {
bip = XFS_BUF_FSPRIVATE(bp,xfs_buf_log_item_t*);
if ((bip != NULL) &&
xfs_buf_item_dirty(bip)) {
if (!(XFS_BUF_ISPINNED(bp))) {
XFS_BUF_ASYNC(bp);
error = xfs_bwrite(mp, bp);
} else {
xfs_buf_relse(bp);
}
} else {
xfs_buf_relse(bp);
}
}
} else {
bp = xfs_getsb(mp, 0);
/*
* If the buffer is pinned then push on the log so
* we won't get stuck waiting in the write for
* someone, maybe ourselves, to flush the log.
* Even though we just pushed the log above, we
* did not have the superblock buffer locked at
* that point so it can become pinned in between
* there and here.
*/
if (XFS_BUF_ISPINNED(bp))
xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE);
if (flags & SYNC_WAIT)
XFS_BUF_UNASYNC(bp);
else
XFS_BUF_ASYNC(bp);
error = xfs_bwrite(mp, bp);
}
if (error) {
last_error = error;
}
}
/*
* Now check to see if the log needs a "dummy" transaction.
*/
if (!(flags & SYNC_REMOUNT) && xfs_log_need_covered(mp)) {
xfs_trans_t *tp;
xfs_inode_t *ip;
/*
* Put a dummy transaction in the log to tell
* recovery that all others are OK.
*/
tp = xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
if ((error = xfs_trans_reserve(tp, 0,
XFS_ICHANGE_LOG_RES(mp),
0, 0, 0))) {
xfs_trans_cancel(tp, 0);
return error;
}
ip = mp->m_rootip;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_ihold(tp, ip);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
error = xfs_trans_commit(tp, 0);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
xfs_log_force(mp, (xfs_lsn_t)0, log_flags);
}
/*
* When shutting down, we need to insure that the AIL is pushed
* to disk or the filesystem can appear corrupt from the PROM.
*/
if ((flags & (SYNC_CLOSE|SYNC_WAIT)) == (SYNC_CLOSE|SYNC_WAIT)) {
XFS_bflush(mp->m_ddev_targp);
if (mp->m_rtdev_targp) {
XFS_bflush(mp->m_rtdev_targp);
}
}
return XFS_ERROR(last_error);
}
/*
* Enqueue a work item to be picked up by the vfs xfssyncd thread.
* Doing this has two advantages:
* - It saves on stack space, which is tight in certain situations
* - It can be used (with care) as a mechanism to avoid deadlocks.
* Flushing while allocating in a full filesystem requires both.
*/
STATIC void
xfs_syncd_queue_work(
struct xfs_mount *mp,
void *data,
void (*syncer)(struct xfs_mount *, void *))
{
struct bhv_vfs_sync_work *work;
work = kmem_alloc(sizeof(struct bhv_vfs_sync_work), KM_SLEEP);
INIT_LIST_HEAD(&work->w_list);
work->w_syncer = syncer;
work->w_data = data;
work->w_mount = mp;
spin_lock(&mp->m_sync_lock);
list_add_tail(&work->w_list, &mp->m_sync_list);
spin_unlock(&mp->m_sync_lock);
wake_up_process(mp->m_sync_task);
}
/*
* Flush delayed allocate data, attempting to free up reserved space
* from existing allocations. At this point a new allocation attempt
* has failed with ENOSPC and we are in the process of scratching our
* heads, looking about for more room...
*/
STATIC void
xfs_flush_inode_work(
struct xfs_mount *mp,
void *arg)
{
struct inode *inode = arg;
filemap_flush(inode->i_mapping);
iput(inode);
}
void
xfs_flush_inode(
xfs_inode_t *ip)
{
struct inode *inode = VFS_I(ip);
igrab(inode);
xfs_syncd_queue_work(ip->i_mount, inode, xfs_flush_inode_work);
delay(msecs_to_jiffies(500));
}
/*
* This is the "bigger hammer" version of xfs_flush_inode_work...
* (IOW, "If at first you don't succeed, use a Bigger Hammer").
*/
STATIC void
xfs_flush_device_work(
struct xfs_mount *mp,
void *arg)
{
struct inode *inode = arg;
sync_blockdev(mp->m_super->s_bdev);
iput(inode);
}
void
xfs_flush_device(
xfs_inode_t *ip)
{
struct inode *inode = VFS_I(ip);
igrab(inode);
xfs_syncd_queue_work(ip->i_mount, inode, xfs_flush_device_work);
delay(msecs_to_jiffies(500));
xfs_log_force(ip->i_mount, (xfs_lsn_t)0, XFS_LOG_FORCE|XFS_LOG_SYNC);
}
STATIC void
xfs_sync_worker(
struct xfs_mount *mp,
void *unused)
{
int error;
if (!(mp->m_flags & XFS_MOUNT_RDONLY))
error = xfs_sync(mp, SYNC_FSDATA | SYNC_BDFLUSH | SYNC_ATTR);
mp->m_sync_seq++;
wake_up(&mp->m_wait_single_sync_task);
}
STATIC int
xfssyncd(
void *arg)
{
struct xfs_mount *mp = arg;
long timeleft;
bhv_vfs_sync_work_t *work, *n;
LIST_HEAD (tmp);
set_freezable();
timeleft = xfs_syncd_centisecs * msecs_to_jiffies(10);
for (;;) {
timeleft = schedule_timeout_interruptible(timeleft);
/* swsusp */
try_to_freeze();
if (kthread_should_stop() && list_empty(&mp->m_sync_list))
break;
spin_lock(&mp->m_sync_lock);
/*
* We can get woken by laptop mode, to do a sync -
* that's the (only!) case where the list would be
* empty with time remaining.
*/
if (!timeleft || list_empty(&mp->m_sync_list)) {
if (!timeleft)
timeleft = xfs_syncd_centisecs *
msecs_to_jiffies(10);
INIT_LIST_HEAD(&mp->m_sync_work.w_list);
list_add_tail(&mp->m_sync_work.w_list,
&mp->m_sync_list);
}
list_for_each_entry_safe(work, n, &mp->m_sync_list, w_list)
list_move(&work->w_list, &tmp);
spin_unlock(&mp->m_sync_lock);
list_for_each_entry_safe(work, n, &tmp, w_list) {
(*work->w_syncer)(mp, work->w_data);
list_del(&work->w_list);
if (work == &mp->m_sync_work)
continue;
kmem_free(work);
}
}
return 0;
}
int
xfs_syncd_init(
struct xfs_mount *mp)
{
mp->m_sync_work.w_syncer = xfs_sync_worker;
mp->m_sync_work.w_mount = mp;
mp->m_sync_task = kthread_run(xfssyncd, mp, "xfssyncd");
if (IS_ERR(mp->m_sync_task))
return -PTR_ERR(mp->m_sync_task);
return 0;
}
void
xfs_syncd_stop(
struct xfs_mount *mp)
{
kthread_stop(mp->m_sync_task);
}