linux/fs/xfs/xfs_trans_buf.c
Dave Chinner 7401aafd50 xfs: xfs_trans_read_buf() should return an error on failure
When inside a transaction and we fail to read a buffer,
xfs_trans_read_buf returns a null buffer pointer and no error.
xfs_do_da_buf() checks the error return, but not the buffer, and as
a result this read failure condition causes a panic when it attempts
to dereference the non-existant buffer.

Make xfs_trans_read_buf() return the same error for this situation
regardless of whether it is in a transaction or not. This means
every caller does not need to check both the error return and the
buffer before proceeding to use the buffer.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
2011-03-26 09:14:44 +11:00

880 lines
25 KiB
C

/*
* Copyright (c) 2000-2002,2005 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_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_buf_item.h"
#include "xfs_trans_priv.h"
#include "xfs_error.h"
#include "xfs_rw.h"
#include "xfs_trace.h"
/*
* Check to see if a buffer matching the given parameters is already
* a part of the given transaction.
*/
STATIC struct xfs_buf *
xfs_trans_buf_item_match(
struct xfs_trans *tp,
struct xfs_buftarg *target,
xfs_daddr_t blkno,
int len)
{
struct xfs_log_item_desc *lidp;
struct xfs_buf_log_item *blip;
len = BBTOB(len);
list_for_each_entry(lidp, &tp->t_items, lid_trans) {
blip = (struct xfs_buf_log_item *)lidp->lid_item;
if (blip->bli_item.li_type == XFS_LI_BUF &&
XFS_BUF_TARGET(blip->bli_buf) == target &&
XFS_BUF_ADDR(blip->bli_buf) == blkno &&
XFS_BUF_COUNT(blip->bli_buf) == len)
return blip->bli_buf;
}
return NULL;
}
/*
* Add the locked buffer to the transaction.
*
* The buffer must be locked, and it cannot be associated with any
* transaction.
*
* If the buffer does not yet have a buf log item associated with it,
* then allocate one for it. Then add the buf item to the transaction.
*/
STATIC void
_xfs_trans_bjoin(
struct xfs_trans *tp,
struct xfs_buf *bp,
int reset_recur)
{
struct xfs_buf_log_item *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL);
/*
* The xfs_buf_log_item pointer is stored in b_fsprivate. If
* it doesn't have one yet, then allocate one and initialize it.
* The checks to see if one is there are in xfs_buf_item_init().
*/
xfs_buf_item_init(bp, tp->t_mountp);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
ASSERT(!(bip->bli_format.blf_flags & XFS_BLF_CANCEL));
ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
if (reset_recur)
bip->bli_recur = 0;
/*
* Take a reference for this transaction on the buf item.
*/
atomic_inc(&bip->bli_refcount);
/*
* Get a log_item_desc to point at the new item.
*/
xfs_trans_add_item(tp, &bip->bli_item);
/*
* Initialize b_fsprivate2 so we can find it with incore_match()
* in xfs_trans_get_buf() and friends above.
*/
XFS_BUF_SET_FSPRIVATE2(bp, tp);
}
void
xfs_trans_bjoin(
struct xfs_trans *tp,
struct xfs_buf *bp)
{
_xfs_trans_bjoin(tp, bp, 0);
trace_xfs_trans_bjoin(bp->b_fspriv);
}
/*
* Get and lock the buffer for the caller if it is not already
* locked within the given transaction. If it is already locked
* within the transaction, just increment its lock recursion count
* and return a pointer to it.
*
* If the transaction pointer is NULL, make this just a normal
* get_buf() call.
*/
xfs_buf_t *
xfs_trans_get_buf(xfs_trans_t *tp,
xfs_buftarg_t *target_dev,
xfs_daddr_t blkno,
int len,
uint flags)
{
xfs_buf_t *bp;
xfs_buf_log_item_t *bip;
if (flags == 0)
flags = XBF_LOCK | XBF_MAPPED;
/*
* Default to a normal get_buf() call if the tp is NULL.
*/
if (tp == NULL)
return xfs_buf_get(target_dev, blkno, len,
flags | XBF_DONT_BLOCK);
/*
* If we find the buffer in the cache with this transaction
* pointer in its b_fsprivate2 field, then we know we already
* have it locked. In this case we just increment the lock
* recursion count and return the buffer to the caller.
*/
bp = xfs_trans_buf_item_match(tp, target_dev, blkno, len);
if (bp != NULL) {
ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
if (XFS_FORCED_SHUTDOWN(tp->t_mountp))
XFS_BUF_SUPER_STALE(bp);
/*
* If the buffer is stale then it was binval'ed
* since last read. This doesn't matter since the
* caller isn't allowed to use the data anyway.
*/
else if (XFS_BUF_ISSTALE(bp))
ASSERT(!XFS_BUF_ISDELAYWRITE(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(bip != NULL);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_recur++;
trace_xfs_trans_get_buf_recur(bip);
return (bp);
}
/*
* We always specify the XBF_DONT_BLOCK flag within a transaction
* so that get_buf does not try to push out a delayed write buffer
* which might cause another transaction to take place (if the
* buffer was delayed alloc). Such recursive transactions can
* easily deadlock with our current transaction as well as cause
* us to run out of stack space.
*/
bp = xfs_buf_get(target_dev, blkno, len, flags | XBF_DONT_BLOCK);
if (bp == NULL) {
return NULL;
}
ASSERT(!XFS_BUF_GETERROR(bp));
_xfs_trans_bjoin(tp, bp, 1);
trace_xfs_trans_get_buf(bp->b_fspriv);
return (bp);
}
/*
* Get and lock the superblock buffer of this file system for the
* given transaction.
*
* We don't need to use incore_match() here, because the superblock
* buffer is a private buffer which we keep a pointer to in the
* mount structure.
*/
xfs_buf_t *
xfs_trans_getsb(xfs_trans_t *tp,
struct xfs_mount *mp,
int flags)
{
xfs_buf_t *bp;
xfs_buf_log_item_t *bip;
/*
* Default to just trying to lock the superblock buffer
* if tp is NULL.
*/
if (tp == NULL) {
return (xfs_getsb(mp, flags));
}
/*
* If the superblock buffer already has this transaction
* pointer in its b_fsprivate2 field, then we know we already
* have it locked. In this case we just increment the lock
* recursion count and return the buffer to the caller.
*/
bp = mp->m_sb_bp;
if (XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp) {
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
ASSERT(bip != NULL);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_recur++;
trace_xfs_trans_getsb_recur(bip);
return (bp);
}
bp = xfs_getsb(mp, flags);
if (bp == NULL)
return NULL;
_xfs_trans_bjoin(tp, bp, 1);
trace_xfs_trans_getsb(bp->b_fspriv);
return (bp);
}
#ifdef DEBUG
xfs_buftarg_t *xfs_error_target;
int xfs_do_error;
int xfs_req_num;
int xfs_error_mod = 33;
#endif
/*
* Get and lock the buffer for the caller if it is not already
* locked within the given transaction. If it has not yet been
* read in, read it from disk. If it is already locked
* within the transaction and already read in, just increment its
* lock recursion count and return a pointer to it.
*
* If the transaction pointer is NULL, make this just a normal
* read_buf() call.
*/
int
xfs_trans_read_buf(
xfs_mount_t *mp,
xfs_trans_t *tp,
xfs_buftarg_t *target,
xfs_daddr_t blkno,
int len,
uint flags,
xfs_buf_t **bpp)
{
xfs_buf_t *bp;
xfs_buf_log_item_t *bip;
int error;
if (flags == 0)
flags = XBF_LOCK | XBF_MAPPED;
/*
* Default to a normal get_buf() call if the tp is NULL.
*/
if (tp == NULL) {
bp = xfs_buf_read(target, blkno, len, flags | XBF_DONT_BLOCK);
if (!bp)
return (flags & XBF_TRYLOCK) ?
EAGAIN : XFS_ERROR(ENOMEM);
if (XFS_BUF_GETERROR(bp) != 0) {
xfs_ioerror_alert("xfs_trans_read_buf", mp,
bp, blkno);
error = XFS_BUF_GETERROR(bp);
xfs_buf_relse(bp);
return error;
}
#ifdef DEBUG
if (xfs_do_error) {
if (xfs_error_target == target) {
if (((xfs_req_num++) % xfs_error_mod) == 0) {
xfs_buf_relse(bp);
xfs_debug(mp, "Returning error!");
return XFS_ERROR(EIO);
}
}
}
#endif
if (XFS_FORCED_SHUTDOWN(mp))
goto shutdown_abort;
*bpp = bp;
return 0;
}
/*
* If we find the buffer in the cache with this transaction
* pointer in its b_fsprivate2 field, then we know we already
* have it locked. If it is already read in we just increment
* the lock recursion count and return the buffer to the caller.
* If the buffer is not yet read in, then we read it in, increment
* the lock recursion count, and return it to the caller.
*/
bp = xfs_trans_buf_item_match(tp, target, blkno, len);
if (bp != NULL) {
ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
ASSERT((XFS_BUF_ISERROR(bp)) == 0);
if (!(XFS_BUF_ISDONE(bp))) {
trace_xfs_trans_read_buf_io(bp, _RET_IP_);
ASSERT(!XFS_BUF_ISASYNC(bp));
XFS_BUF_READ(bp);
xfsbdstrat(tp->t_mountp, bp);
error = xfs_buf_iowait(bp);
if (error) {
xfs_ioerror_alert("xfs_trans_read_buf", mp,
bp, blkno);
xfs_buf_relse(bp);
/*
* We can gracefully recover from most read
* errors. Ones we can't are those that happen
* after the transaction's already dirty.
*/
if (tp->t_flags & XFS_TRANS_DIRTY)
xfs_force_shutdown(tp->t_mountp,
SHUTDOWN_META_IO_ERROR);
return error;
}
}
/*
* We never locked this buf ourselves, so we shouldn't
* brelse it either. Just get out.
*/
if (XFS_FORCED_SHUTDOWN(mp)) {
trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
*bpp = NULL;
return XFS_ERROR(EIO);
}
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t*);
bip->bli_recur++;
ASSERT(atomic_read(&bip->bli_refcount) > 0);
trace_xfs_trans_read_buf_recur(bip);
*bpp = bp;
return 0;
}
/*
* We always specify the XBF_DONT_BLOCK flag within a transaction
* so that get_buf does not try to push out a delayed write buffer
* which might cause another transaction to take place (if the
* buffer was delayed alloc). Such recursive transactions can
* easily deadlock with our current transaction as well as cause
* us to run out of stack space.
*/
bp = xfs_buf_read(target, blkno, len, flags | XBF_DONT_BLOCK);
if (bp == NULL) {
*bpp = NULL;
return (flags & XBF_TRYLOCK) ?
0 : XFS_ERROR(ENOMEM);
}
if (XFS_BUF_GETERROR(bp) != 0) {
XFS_BUF_SUPER_STALE(bp);
error = XFS_BUF_GETERROR(bp);
xfs_ioerror_alert("xfs_trans_read_buf", mp,
bp, blkno);
if (tp->t_flags & XFS_TRANS_DIRTY)
xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
xfs_buf_relse(bp);
return error;
}
#ifdef DEBUG
if (xfs_do_error && !(tp->t_flags & XFS_TRANS_DIRTY)) {
if (xfs_error_target == target) {
if (((xfs_req_num++) % xfs_error_mod) == 0) {
xfs_force_shutdown(tp->t_mountp,
SHUTDOWN_META_IO_ERROR);
xfs_buf_relse(bp);
xfs_debug(mp, "Returning trans error!");
return XFS_ERROR(EIO);
}
}
}
#endif
if (XFS_FORCED_SHUTDOWN(mp))
goto shutdown_abort;
_xfs_trans_bjoin(tp, bp, 1);
trace_xfs_trans_read_buf(bp->b_fspriv);
*bpp = bp;
return 0;
shutdown_abort:
/*
* the theory here is that buffer is good but we're
* bailing out because the filesystem is being forcibly
* shut down. So we should leave the b_flags alone since
* the buffer's not staled and just get out.
*/
#if defined(DEBUG)
if (XFS_BUF_ISSTALE(bp) && XFS_BUF_ISDELAYWRITE(bp))
xfs_notice(mp, "about to pop assert, bp == 0x%p", bp);
#endif
ASSERT((XFS_BUF_BFLAGS(bp) & (XBF_STALE|XBF_DELWRI)) !=
(XBF_STALE|XBF_DELWRI));
trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
xfs_buf_relse(bp);
*bpp = NULL;
return XFS_ERROR(EIO);
}
/*
* Release the buffer bp which was previously acquired with one of the
* xfs_trans_... buffer allocation routines if the buffer has not
* been modified within this transaction. If the buffer is modified
* within this transaction, do decrement the recursion count but do
* not release the buffer even if the count goes to 0. If the buffer is not
* modified within the transaction, decrement the recursion count and
* release the buffer if the recursion count goes to 0.
*
* If the buffer is to be released and it was not modified before
* this transaction began, then free the buf_log_item associated with it.
*
* If the transaction pointer is NULL, make this just a normal
* brelse() call.
*/
void
xfs_trans_brelse(xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
xfs_log_item_t *lip;
/*
* Default to a normal brelse() call if the tp is NULL.
*/
if (tp == NULL) {
ASSERT(XFS_BUF_FSPRIVATE2(bp, void *) == NULL);
/*
* If there's a buf log item attached to the buffer,
* then let the AIL know that the buffer is being
* unlocked.
*/
if (XFS_BUF_FSPRIVATE(bp, void *) != NULL) {
lip = XFS_BUF_FSPRIVATE(bp, xfs_log_item_t *);
if (lip->li_type == XFS_LI_BUF) {
bip = XFS_BUF_FSPRIVATE(bp,xfs_buf_log_item_t*);
xfs_trans_unlocked_item(bip->bli_item.li_ailp,
lip);
}
}
xfs_buf_relse(bp);
return;
}
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
ASSERT(!(bip->bli_format.blf_flags & XFS_BLF_CANCEL));
ASSERT(atomic_read(&bip->bli_refcount) > 0);
trace_xfs_trans_brelse(bip);
/*
* If the release is just for a recursive lock,
* then decrement the count and return.
*/
if (bip->bli_recur > 0) {
bip->bli_recur--;
return;
}
/*
* If the buffer is dirty within this transaction, we can't
* release it until we commit.
*/
if (bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY)
return;
/*
* If the buffer has been invalidated, then we can't release
* it until the transaction commits to disk unless it is re-dirtied
* as part of this transaction. This prevents us from pulling
* the item from the AIL before we should.
*/
if (bip->bli_flags & XFS_BLI_STALE)
return;
ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
/*
* Free up the log item descriptor tracking the released item.
*/
xfs_trans_del_item(&bip->bli_item);
/*
* Clear the hold flag in the buf log item if it is set.
* We wouldn't want the next user of the buffer to
* get confused.
*/
if (bip->bli_flags & XFS_BLI_HOLD) {
bip->bli_flags &= ~XFS_BLI_HOLD;
}
/*
* Drop our reference to the buf log item.
*/
atomic_dec(&bip->bli_refcount);
/*
* If the buf item is not tracking data in the log, then
* we must free it before releasing the buffer back to the
* free pool. Before releasing the buffer to the free pool,
* clear the transaction pointer in b_fsprivate2 to dissolve
* its relation to this transaction.
*/
if (!xfs_buf_item_dirty(bip)) {
/***
ASSERT(bp->b_pincount == 0);
***/
ASSERT(atomic_read(&bip->bli_refcount) == 0);
ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL));
ASSERT(!(bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF));
xfs_buf_item_relse(bp);
bip = NULL;
}
XFS_BUF_SET_FSPRIVATE2(bp, NULL);
/*
* If we've still got a buf log item on the buffer, then
* tell the AIL that the buffer is being unlocked.
*/
if (bip != NULL) {
xfs_trans_unlocked_item(bip->bli_item.li_ailp,
(xfs_log_item_t*)bip);
}
xfs_buf_relse(bp);
return;
}
/*
* Mark the buffer as not needing to be unlocked when the buf item's
* IOP_UNLOCK() routine is called. The buffer must already be locked
* and associated with the given transaction.
*/
/* ARGSUSED */
void
xfs_trans_bhold(xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
ASSERT(!(bip->bli_format.blf_flags & XFS_BLF_CANCEL));
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_flags |= XFS_BLI_HOLD;
trace_xfs_trans_bhold(bip);
}
/*
* Cancel the previous buffer hold request made on this buffer
* for this transaction.
*/
void
xfs_trans_bhold_release(xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
ASSERT(!(bip->bli_format.blf_flags & XFS_BLF_CANCEL));
ASSERT(atomic_read(&bip->bli_refcount) > 0);
ASSERT(bip->bli_flags & XFS_BLI_HOLD);
bip->bli_flags &= ~XFS_BLI_HOLD;
trace_xfs_trans_bhold_release(bip);
}
/*
* This is called to mark bytes first through last inclusive of the given
* buffer as needing to be logged when the transaction is committed.
* The buffer must already be associated with the given transaction.
*
* First and last are numbers relative to the beginning of this buffer,
* so the first byte in the buffer is numbered 0 regardless of the
* value of b_blkno.
*/
void
xfs_trans_log_buf(xfs_trans_t *tp,
xfs_buf_t *bp,
uint first,
uint last)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
ASSERT((first <= last) && (last < XFS_BUF_COUNT(bp)));
ASSERT((XFS_BUF_IODONE_FUNC(bp) == NULL) ||
(XFS_BUF_IODONE_FUNC(bp) == xfs_buf_iodone_callbacks));
/*
* Mark the buffer as needing to be written out eventually,
* and set its iodone function to remove the buffer's buf log
* item from the AIL and free it when the buffer is flushed
* to disk. See xfs_buf_attach_iodone() for more details
* on li_cb and xfs_buf_iodone_callbacks().
* If we end up aborting this transaction, we trap this buffer
* inside the b_bdstrat callback so that this won't get written to
* disk.
*/
XFS_BUF_DELAYWRITE(bp);
XFS_BUF_DONE(bp);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
XFS_BUF_SET_IODONE_FUNC(bp, xfs_buf_iodone_callbacks);
bip->bli_item.li_cb = xfs_buf_iodone;
trace_xfs_trans_log_buf(bip);
/*
* If we invalidated the buffer within this transaction, then
* cancel the invalidation now that we're dirtying the buffer
* again. There are no races with the code in xfs_buf_item_unpin(),
* because we have a reference to the buffer this entire time.
*/
if (bip->bli_flags & XFS_BLI_STALE) {
bip->bli_flags &= ~XFS_BLI_STALE;
ASSERT(XFS_BUF_ISSTALE(bp));
XFS_BUF_UNSTALE(bp);
bip->bli_format.blf_flags &= ~XFS_BLF_CANCEL;
}
tp->t_flags |= XFS_TRANS_DIRTY;
bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
bip->bli_flags |= XFS_BLI_LOGGED;
xfs_buf_item_log(bip, first, last);
}
/*
* This called to invalidate a buffer that is being used within
* a transaction. Typically this is because the blocks in the
* buffer are being freed, so we need to prevent it from being
* written out when we're done. Allowing it to be written again
* might overwrite data in the free blocks if they are reallocated
* to a file.
*
* We prevent the buffer from being written out by clearing the
* B_DELWRI flag. We can't always
* get rid of the buf log item at this point, though, because
* the buffer may still be pinned by another transaction. If that
* is the case, then we'll wait until the buffer is committed to
* disk for the last time (we can tell by the ref count) and
* free it in xfs_buf_item_unpin(). Until it is cleaned up we
* will keep the buffer locked so that the buffer and buf log item
* are not reused.
*/
void
xfs_trans_binval(
xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
trace_xfs_trans_binval(bip);
if (bip->bli_flags & XFS_BLI_STALE) {
/*
* If the buffer is already invalidated, then
* just return.
*/
ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
ASSERT(XFS_BUF_ISSTALE(bp));
ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
ASSERT(!(bip->bli_format.blf_flags & XFS_BLF_INODE_BUF));
ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
ASSERT(bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY);
ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
return;
}
/*
* Clear the dirty bit in the buffer and set the STALE flag
* in the buf log item. The STALE flag will be used in
* xfs_buf_item_unpin() to determine if it should clean up
* when the last reference to the buf item is given up.
* We set the XFS_BLF_CANCEL flag in the buf log format structure
* and log the buf item. This will be used at recovery time
* to determine that copies of the buffer in the log before
* this should not be replayed.
* We mark the item descriptor and the transaction dirty so
* that we'll hold the buffer until after the commit.
*
* Since we're invalidating the buffer, we also clear the state
* about which parts of the buffer have been logged. We also
* clear the flag indicating that this is an inode buffer since
* the data in the buffer will no longer be valid.
*
* We set the stale bit in the buffer as well since we're getting
* rid of it.
*/
XFS_BUF_UNDELAYWRITE(bp);
XFS_BUF_STALE(bp);
bip->bli_flags |= XFS_BLI_STALE;
bip->bli_flags &= ~(XFS_BLI_INODE_BUF | XFS_BLI_LOGGED | XFS_BLI_DIRTY);
bip->bli_format.blf_flags &= ~XFS_BLF_INODE_BUF;
bip->bli_format.blf_flags |= XFS_BLF_CANCEL;
memset((char *)(bip->bli_format.blf_data_map), 0,
(bip->bli_format.blf_map_size * sizeof(uint)));
bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
tp->t_flags |= XFS_TRANS_DIRTY;
}
/*
* This call is used to indicate that the buffer contains on-disk inodes which
* must be handled specially during recovery. They require special handling
* because only the di_next_unlinked from the inodes in the buffer should be
* recovered. The rest of the data in the buffer is logged via the inodes
* themselves.
*
* All we do is set the XFS_BLI_INODE_BUF flag in the items flags so it can be
* transferred to the buffer's log format structure so that we'll know what to
* do at recovery time.
*/
void
xfs_trans_inode_buf(
xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_flags |= XFS_BLI_INODE_BUF;
}
/*
* This call is used to indicate that the buffer is going to
* be staled and was an inode buffer. This means it gets
* special processing during unpin - where any inodes
* associated with the buffer should be removed from ail.
* There is also special processing during recovery,
* any replay of the inodes in the buffer needs to be
* prevented as the buffer may have been reused.
*/
void
xfs_trans_stale_inode_buf(
xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_flags |= XFS_BLI_STALE_INODE;
bip->bli_item.li_cb = xfs_buf_iodone;
}
/*
* Mark the buffer as being one which contains newly allocated
* inodes. We need to make sure that even if this buffer is
* relogged as an 'inode buf' we still recover all of the inode
* images in the face of a crash. This works in coordination with
* xfs_buf_item_committed() to ensure that the buffer remains in the
* AIL at its original location even after it has been relogged.
*/
/* ARGSUSED */
void
xfs_trans_inode_alloc_buf(
xfs_trans_t *tp,
xfs_buf_t *bp)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
}
/*
* Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
* dquots. However, unlike in inode buffer recovery, dquot buffers get
* recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
* The only thing that makes dquot buffers different from regular
* buffers is that we must not replay dquot bufs when recovering
* if a _corresponding_ quotaoff has happened. We also have to distinguish
* between usr dquot bufs and grp dquot bufs, because usr and grp quotas
* can be turned off independently.
*/
/* ARGSUSED */
void
xfs_trans_dquot_buf(
xfs_trans_t *tp,
xfs_buf_t *bp,
uint type)
{
xfs_buf_log_item_t *bip;
ASSERT(XFS_BUF_ISBUSY(bp));
ASSERT(XFS_BUF_FSPRIVATE2(bp, xfs_trans_t *) == tp);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
ASSERT(type == XFS_BLF_UDQUOT_BUF ||
type == XFS_BLF_PDQUOT_BUF ||
type == XFS_BLF_GDQUOT_BUF);
bip = XFS_BUF_FSPRIVATE(bp, xfs_buf_log_item_t *);
ASSERT(atomic_read(&bip->bli_refcount) > 0);
bip->bli_format.blf_flags |= type;
}