linux/fs/xfs/xfs_dquot_item.c
Christoph Hellwig 17b38471c3 xfs: force the log if we encounter pinned buffers in .iop_pushbuf
We need to check for pinned buffers even in .iop_pushbuf given that inode
items flush into the same buffers that may be pinned directly due operations
on the unlinked inode list operating directly on buffers.  To do this add a
return value to .iop_pushbuf that tells the AIL push about this and use
the existing log force mechanisms to unpin it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Tested-by: Stefan Priebe <s.priebe@profihost.ag>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 11:02:48 -05:00

534 lines
14 KiB
C

/*
* Copyright (c) 2000-2003 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_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_alloc.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_itable.h"
#include "xfs_attr.h"
#include "xfs_buf_item.h"
#include "xfs_trans_priv.h"
#include "xfs_qm.h"
static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_dq_logitem, qli_item);
}
/*
* returns the number of iovecs needed to log the given dquot item.
*/
STATIC uint
xfs_qm_dquot_logitem_size(
struct xfs_log_item *lip)
{
/*
* we need only two iovecs, one for the format, one for the real thing
*/
return 2;
}
/*
* fills in the vector of log iovecs for the given dquot log item.
*/
STATIC void
xfs_qm_dquot_logitem_format(
struct xfs_log_item *lip,
struct xfs_log_iovec *logvec)
{
struct xfs_dq_logitem *qlip = DQUOT_ITEM(lip);
logvec->i_addr = &qlip->qli_format;
logvec->i_len = sizeof(xfs_dq_logformat_t);
logvec->i_type = XLOG_REG_TYPE_QFORMAT;
logvec++;
logvec->i_addr = &qlip->qli_dquot->q_core;
logvec->i_len = sizeof(xfs_disk_dquot_t);
logvec->i_type = XLOG_REG_TYPE_DQUOT;
ASSERT(2 == lip->li_desc->lid_size);
qlip->qli_format.qlf_size = 2;
}
/*
* Increment the pin count of the given dquot.
*/
STATIC void
xfs_qm_dquot_logitem_pin(
struct xfs_log_item *lip)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
ASSERT(XFS_DQ_IS_LOCKED(dqp));
atomic_inc(&dqp->q_pincount);
}
/*
* Decrement the pin count of the given dquot, and wake up
* anyone in xfs_dqwait_unpin() if the count goes to 0. The
* dquot must have been previously pinned with a call to
* xfs_qm_dquot_logitem_pin().
*/
STATIC void
xfs_qm_dquot_logitem_unpin(
struct xfs_log_item *lip,
int remove)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
ASSERT(atomic_read(&dqp->q_pincount) > 0);
if (atomic_dec_and_test(&dqp->q_pincount))
wake_up(&dqp->q_pinwait);
}
/*
* Given the logitem, this writes the corresponding dquot entry to disk
* asynchronously. This is called with the dquot entry securely locked;
* we simply get xfs_qm_dqflush() to do the work, and unlock the dquot
* at the end.
*/
STATIC void
xfs_qm_dquot_logitem_push(
struct xfs_log_item *lip)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
int error;
ASSERT(XFS_DQ_IS_LOCKED(dqp));
ASSERT(!completion_done(&dqp->q_flush));
/*
* Since we were able to lock the dquot's flush lock and
* we found it on the AIL, the dquot must be dirty. This
* is because the dquot is removed from the AIL while still
* holding the flush lock in xfs_dqflush_done(). Thus, if
* we found it in the AIL and were able to obtain the flush
* lock without sleeping, then there must not have been
* anyone in the process of flushing the dquot.
*/
error = xfs_qm_dqflush(dqp, 0);
if (error)
xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
__func__, error, dqp);
xfs_dqunlock(dqp);
}
STATIC xfs_lsn_t
xfs_qm_dquot_logitem_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
/*
* We always re-log the entire dquot when it becomes dirty,
* so, the latest copy _is_ the only one that matters.
*/
return lsn;
}
/*
* This is called to wait for the given dquot to be unpinned.
* Most of these pin/unpin routines are plagiarized from inode code.
*/
void
xfs_qm_dqunpin_wait(
struct xfs_dquot *dqp)
{
ASSERT(XFS_DQ_IS_LOCKED(dqp));
if (atomic_read(&dqp->q_pincount) == 0)
return;
/*
* Give the log a push so we don't wait here too long.
*/
xfs_log_force(dqp->q_mount, 0);
wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
}
/*
* This is called when IOP_TRYLOCK returns XFS_ITEM_PUSHBUF to indicate that
* the dquot is locked by us, but the flush lock isn't. So, here we are
* going to see if the relevant dquot buffer is incore, waiting on DELWRI.
* If so, we want to push it out to help us take this item off the AIL as soon
* as possible.
*
* We must not be holding the AIL lock at this point. Calling incore() to
* search the buffer cache can be a time consuming thing, and AIL lock is a
* spinlock.
*/
STATIC bool
xfs_qm_dquot_logitem_pushbuf(
struct xfs_log_item *lip)
{
struct xfs_dq_logitem *qlip = DQUOT_ITEM(lip);
struct xfs_dquot *dqp = qlip->qli_dquot;
struct xfs_buf *bp;
bool ret = true;
ASSERT(XFS_DQ_IS_LOCKED(dqp));
/*
* If flushlock isn't locked anymore, chances are that the
* inode flush completed and the inode was taken off the AIL.
* So, just get out.
*/
if (completion_done(&dqp->q_flush) ||
!(lip->li_flags & XFS_LI_IN_AIL)) {
xfs_dqunlock(dqp);
return true;
}
bp = xfs_incore(dqp->q_mount->m_ddev_targp, qlip->qli_format.qlf_blkno,
dqp->q_mount->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
xfs_dqunlock(dqp);
if (!bp)
return true;
if (XFS_BUF_ISDELAYWRITE(bp))
xfs_buf_delwri_promote(bp);
if (xfs_buf_ispinned(bp))
ret = false;
xfs_buf_relse(bp);
return ret;
}
/*
* This is called to attempt to lock the dquot associated with this
* dquot log item. Don't sleep on the dquot lock or the flush lock.
* If the flush lock is already held, indicating that the dquot has
* been or is in the process of being flushed, then see if we can
* find the dquot's buffer in the buffer cache without sleeping. If
* we can and it is marked delayed write, then we want to send it out.
* We delay doing so until the push routine, though, to avoid sleeping
* in any device strategy routines.
*/
STATIC uint
xfs_qm_dquot_logitem_trylock(
struct xfs_log_item *lip)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
if (atomic_read(&dqp->q_pincount) > 0)
return XFS_ITEM_PINNED;
if (!xfs_qm_dqlock_nowait(dqp))
return XFS_ITEM_LOCKED;
if (!xfs_dqflock_nowait(dqp)) {
/*
* dquot has already been flushed to the backing buffer,
* leave it locked, pushbuf routine will unlock it.
*/
return XFS_ITEM_PUSHBUF;
}
ASSERT(lip->li_flags & XFS_LI_IN_AIL);
return XFS_ITEM_SUCCESS;
}
/*
* Unlock the dquot associated with the log item.
* Clear the fields of the dquot and dquot log item that
* are specific to the current transaction. If the
* hold flags is set, do not unlock the dquot.
*/
STATIC void
xfs_qm_dquot_logitem_unlock(
struct xfs_log_item *lip)
{
struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
ASSERT(XFS_DQ_IS_LOCKED(dqp));
/*
* Clear the transaction pointer in the dquot
*/
dqp->q_transp = NULL;
/*
* dquots are never 'held' from getting unlocked at the end of
* a transaction. Their locking and unlocking is hidden inside the
* transaction layer, within trans_commit. Hence, no LI_HOLD flag
* for the logitem.
*/
xfs_dqunlock(dqp);
}
/*
* this needs to stamp an lsn into the dquot, I think.
* rpc's that look at user dquot's would then have to
* push on the dependency recorded in the dquot
*/
STATIC void
xfs_qm_dquot_logitem_committing(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
}
/*
* This is the ops vector for dquots
*/
static struct xfs_item_ops xfs_dquot_item_ops = {
.iop_size = xfs_qm_dquot_logitem_size,
.iop_format = xfs_qm_dquot_logitem_format,
.iop_pin = xfs_qm_dquot_logitem_pin,
.iop_unpin = xfs_qm_dquot_logitem_unpin,
.iop_trylock = xfs_qm_dquot_logitem_trylock,
.iop_unlock = xfs_qm_dquot_logitem_unlock,
.iop_committed = xfs_qm_dquot_logitem_committed,
.iop_push = xfs_qm_dquot_logitem_push,
.iop_pushbuf = xfs_qm_dquot_logitem_pushbuf,
.iop_committing = xfs_qm_dquot_logitem_committing
};
/*
* Initialize the dquot log item for a newly allocated dquot.
* The dquot isn't locked at this point, but it isn't on any of the lists
* either, so we don't care.
*/
void
xfs_qm_dquot_logitem_init(
struct xfs_dquot *dqp)
{
struct xfs_dq_logitem *lp = &dqp->q_logitem;
xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
&xfs_dquot_item_ops);
lp->qli_dquot = dqp;
lp->qli_format.qlf_type = XFS_LI_DQUOT;
lp->qli_format.qlf_id = be32_to_cpu(dqp->q_core.d_id);
lp->qli_format.qlf_blkno = dqp->q_blkno;
lp->qli_format.qlf_len = 1;
/*
* This is just the offset of this dquot within its buffer
* (which is currently 1 FSB and probably won't change).
* Hence 32 bits for this offset should be just fine.
* Alternatively, we can store (bufoffset / sizeof(xfs_dqblk_t))
* here, and recompute it at recovery time.
*/
lp->qli_format.qlf_boffset = (__uint32_t)dqp->q_bufoffset;
}
/*------------------ QUOTAOFF LOG ITEMS -------------------*/
static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_qoff_logitem, qql_item);
}
/*
* This returns the number of iovecs needed to log the given quotaoff item.
* We only need 1 iovec for an quotaoff item. It just logs the
* quotaoff_log_format structure.
*/
STATIC uint
xfs_qm_qoff_logitem_size(
struct xfs_log_item *lip)
{
return 1;
}
/*
* This is called to fill in the vector of log iovecs for the
* given quotaoff log item. We use only 1 iovec, and we point that
* at the quotaoff_log_format structure embedded in the quotaoff item.
* It is at this point that we assert that all of the extent
* slots in the quotaoff item have been filled.
*/
STATIC void
xfs_qm_qoff_logitem_format(
struct xfs_log_item *lip,
struct xfs_log_iovec *log_vector)
{
struct xfs_qoff_logitem *qflip = QOFF_ITEM(lip);
ASSERT(qflip->qql_format.qf_type == XFS_LI_QUOTAOFF);
log_vector->i_addr = &qflip->qql_format;
log_vector->i_len = sizeof(xfs_qoff_logitem_t);
log_vector->i_type = XLOG_REG_TYPE_QUOTAOFF;
qflip->qql_format.qf_size = 1;
}
/*
* Pinning has no meaning for an quotaoff item, so just return.
*/
STATIC void
xfs_qm_qoff_logitem_pin(
struct xfs_log_item *lip)
{
}
/*
* Since pinning has no meaning for an quotaoff item, unpinning does
* not either.
*/
STATIC void
xfs_qm_qoff_logitem_unpin(
struct xfs_log_item *lip,
int remove)
{
}
/*
* Quotaoff items have no locking, so just return success.
*/
STATIC uint
xfs_qm_qoff_logitem_trylock(
struct xfs_log_item *lip)
{
return XFS_ITEM_LOCKED;
}
/*
* Quotaoff items have no locking or pushing, so return failure
* so that the caller doesn't bother with us.
*/
STATIC void
xfs_qm_qoff_logitem_unlock(
struct xfs_log_item *lip)
{
}
/*
* The quotaoff-start-item is logged only once and cannot be moved in the log,
* so simply return the lsn at which it's been logged.
*/
STATIC xfs_lsn_t
xfs_qm_qoff_logitem_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
return lsn;
}
/*
* There isn't much you can do to push on an quotaoff item. It is simply
* stuck waiting for the log to be flushed to disk.
*/
STATIC void
xfs_qm_qoff_logitem_push(
struct xfs_log_item *lip)
{
}
STATIC xfs_lsn_t
xfs_qm_qoffend_logitem_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
struct xfs_qoff_logitem *qfe = QOFF_ITEM(lip);
struct xfs_qoff_logitem *qfs = qfe->qql_start_lip;
struct xfs_ail *ailp = qfs->qql_item.li_ailp;
/*
* Delete the qoff-start logitem from the AIL.
* xfs_trans_ail_delete() drops the AIL lock.
*/
spin_lock(&ailp->xa_lock);
xfs_trans_ail_delete(ailp, (xfs_log_item_t *)qfs);
kmem_free(qfs);
kmem_free(qfe);
return (xfs_lsn_t)-1;
}
/*
* XXX rcc - don't know quite what to do with this. I think we can
* just ignore it. The only time that isn't the case is if we allow
* the client to somehow see that quotas have been turned off in which
* we can't allow that to get back until the quotaoff hits the disk.
* So how would that happen? Also, do we need different routines for
* quotaoff start and quotaoff end? I suspect the answer is yes but
* to be sure, I need to look at the recovery code and see how quota off
* recovery is handled (do we roll forward or back or do something else).
* If we roll forwards or backwards, then we need two separate routines,
* one that does nothing and one that stamps in the lsn that matters
* (truly makes the quotaoff irrevocable). If we do something else,
* then maybe we don't need two.
*/
STATIC void
xfs_qm_qoff_logitem_committing(
struct xfs_log_item *lip,
xfs_lsn_t commit_lsn)
{
}
static struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
.iop_size = xfs_qm_qoff_logitem_size,
.iop_format = xfs_qm_qoff_logitem_format,
.iop_pin = xfs_qm_qoff_logitem_pin,
.iop_unpin = xfs_qm_qoff_logitem_unpin,
.iop_trylock = xfs_qm_qoff_logitem_trylock,
.iop_unlock = xfs_qm_qoff_logitem_unlock,
.iop_committed = xfs_qm_qoffend_logitem_committed,
.iop_push = xfs_qm_qoff_logitem_push,
.iop_committing = xfs_qm_qoff_logitem_committing
};
/*
* This is the ops vector shared by all quotaoff-start log items.
*/
static struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
.iop_size = xfs_qm_qoff_logitem_size,
.iop_format = xfs_qm_qoff_logitem_format,
.iop_pin = xfs_qm_qoff_logitem_pin,
.iop_unpin = xfs_qm_qoff_logitem_unpin,
.iop_trylock = xfs_qm_qoff_logitem_trylock,
.iop_unlock = xfs_qm_qoff_logitem_unlock,
.iop_committed = xfs_qm_qoff_logitem_committed,
.iop_push = xfs_qm_qoff_logitem_push,
.iop_committing = xfs_qm_qoff_logitem_committing
};
/*
* Allocate and initialize an quotaoff item of the correct quota type(s).
*/
struct xfs_qoff_logitem *
xfs_qm_qoff_logitem_init(
struct xfs_mount *mp,
struct xfs_qoff_logitem *start,
uint flags)
{
struct xfs_qoff_logitem *qf;
qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
&xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
qf->qql_item.li_mountp = mp;
qf->qql_format.qf_type = XFS_LI_QUOTAOFF;
qf->qql_format.qf_flags = flags;
qf->qql_start_lip = start;
return qf;
}