alistair23-linux/fs/xfs/xfs_trans_extfree.c
Brian Foster 6bc43af3d5 xfs: ensure EFD trans aborts on log recovery extent free failure
Log recovery attempts to free extents with leftover EFIs in the AIL
after initial processing. If the extent free fails (e.g., due to
unrelated fs corruption), the transaction is cancelled, though it
might not be dirtied at the time. If this is the case, the EFD does
not abort and thus does not release the EFI. This can lead to hangs
as the EFI pins the AIL.

Update xlog_recover_process_efi() to log the EFD in the transaction
before xfs_free_extent() errors are handled to ensure the
transaction is dirty, aborts the EFD and releases the EFI on error.
Since this is a requirement for EFD processing (and consistent with
xfs_bmap_finish()), update the EFD logging helper to do the extent
free and unconditionally log the EFD. This encodes the required EFD
logging behavior into the helper and reduces the likelihood of
errors down the road.

[dchinner: re-add xfs_alloc.h to xfs_log_recover.c to fix build
 failure.]

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 09:51:43 +10:00

148 lines
3.8 KiB
C

/*
* 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_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_extfree_item.h"
#include "xfs_alloc.h"
/*
* This routine is called to allocate an "extent free intention"
* log item that will hold nextents worth of extents. The
* caller must use all nextents extents, because we are not
* flexible about this at all.
*/
xfs_efi_log_item_t *
xfs_trans_get_efi(xfs_trans_t *tp,
uint nextents)
{
xfs_efi_log_item_t *efip;
ASSERT(tp != NULL);
ASSERT(nextents > 0);
efip = xfs_efi_init(tp->t_mountp, nextents);
ASSERT(efip != NULL);
/*
* Get a log_item_desc to point at the new item.
*/
xfs_trans_add_item(tp, &efip->efi_item);
return efip;
}
/*
* This routine is called to indicate that the described
* extent is to be logged as needing to be freed. It should
* be called once for each extent to be freed.
*/
void
xfs_trans_log_efi_extent(xfs_trans_t *tp,
xfs_efi_log_item_t *efip,
xfs_fsblock_t start_block,
xfs_extlen_t ext_len)
{
uint next_extent;
xfs_extent_t *extp;
tp->t_flags |= XFS_TRANS_DIRTY;
efip->efi_item.li_desc->lid_flags |= XFS_LID_DIRTY;
/*
* atomic_inc_return gives us the value after the increment;
* we want to use it as an array index so we need to subtract 1 from
* it.
*/
next_extent = atomic_inc_return(&efip->efi_next_extent) - 1;
ASSERT(next_extent < efip->efi_format.efi_nextents);
extp = &(efip->efi_format.efi_extents[next_extent]);
extp->ext_start = start_block;
extp->ext_len = ext_len;
}
/*
* This routine is called to allocate an "extent free done"
* log item that will hold nextents worth of extents. The
* caller must use all nextents extents, because we are not
* flexible about this at all.
*/
xfs_efd_log_item_t *
xfs_trans_get_efd(xfs_trans_t *tp,
xfs_efi_log_item_t *efip,
uint nextents)
{
xfs_efd_log_item_t *efdp;
ASSERT(tp != NULL);
ASSERT(nextents > 0);
efdp = xfs_efd_init(tp->t_mountp, efip, nextents);
ASSERT(efdp != NULL);
/*
* Get a log_item_desc to point at the new item.
*/
xfs_trans_add_item(tp, &efdp->efd_item);
return efdp;
}
/*
* Free an extent and log it to the EFD. Note that the transaction is marked
* dirty regardless of whether the extent free succeeds or fails to support the
* EFI/EFD lifecycle rules.
*/
int
xfs_trans_free_extent(
struct xfs_trans *tp,
struct xfs_efd_log_item *efdp,
xfs_fsblock_t start_block,
xfs_extlen_t ext_len)
{
uint next_extent;
struct xfs_extent *extp;
int error;
error = xfs_free_extent(tp, start_block, ext_len);
/*
* Mark the transaction dirty, even on error. This ensures the
* transaction is aborted, which:
*
* 1.) releases the EFI and frees the EFD
* 2.) shuts down the filesystem
*/
tp->t_flags |= XFS_TRANS_DIRTY;
efdp->efd_item.li_desc->lid_flags |= XFS_LID_DIRTY;
next_extent = efdp->efd_next_extent;
ASSERT(next_extent < efdp->efd_format.efd_nextents);
extp = &(efdp->efd_format.efd_extents[next_extent]);
extp->ext_start = start_block;
extp->ext_len = ext_len;
efdp->efd_next_extent++;
return error;
}