linux-sg2042/fs/xfs/xfs_refcount_item.c

384 lines
10 KiB
C

/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
*
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* 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_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_buf_item.h"
#include "xfs_refcount_item.h"
#include "xfs_log.h"
kmem_zone_t *xfs_cui_zone;
kmem_zone_t *xfs_cud_zone;
static inline struct xfs_cui_log_item *CUI_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_cui_log_item, cui_item);
}
void
xfs_cui_item_free(
struct xfs_cui_log_item *cuip)
{
if (cuip->cui_format.cui_nextents > XFS_CUI_MAX_FAST_EXTENTS)
kmem_free(cuip);
else
kmem_zone_free(xfs_cui_zone, cuip);
}
STATIC void
xfs_cui_item_size(
struct xfs_log_item *lip,
int *nvecs,
int *nbytes)
{
struct xfs_cui_log_item *cuip = CUI_ITEM(lip);
*nvecs += 1;
*nbytes += xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents);
}
/*
* This is called to fill in the vector of log iovecs for the
* given cui log item. We use only 1 iovec, and we point that
* at the cui_log_format structure embedded in the cui item.
* It is at this point that we assert that all of the extent
* slots in the cui item have been filled.
*/
STATIC void
xfs_cui_item_format(
struct xfs_log_item *lip,
struct xfs_log_vec *lv)
{
struct xfs_cui_log_item *cuip = CUI_ITEM(lip);
struct xfs_log_iovec *vecp = NULL;
ASSERT(atomic_read(&cuip->cui_next_extent) ==
cuip->cui_format.cui_nextents);
cuip->cui_format.cui_type = XFS_LI_CUI;
cuip->cui_format.cui_size = 1;
xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUI_FORMAT, &cuip->cui_format,
xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents));
}
/*
* Pinning has no meaning for an cui item, so just return.
*/
STATIC void
xfs_cui_item_pin(
struct xfs_log_item *lip)
{
}
/*
* The unpin operation is the last place an CUI is manipulated in the log. It is
* either inserted in the AIL or aborted in the event of a log I/O error. In
* either case, the CUI transaction has been successfully committed to make it
* this far. Therefore, we expect whoever committed the CUI to either construct
* and commit the CUD or drop the CUD's reference in the event of error. Simply
* drop the log's CUI reference now that the log is done with it.
*/
STATIC void
xfs_cui_item_unpin(
struct xfs_log_item *lip,
int remove)
{
struct xfs_cui_log_item *cuip = CUI_ITEM(lip);
xfs_cui_release(cuip);
}
/*
* CUI items have no locking or pushing. However, since CUIs are pulled from
* the AIL when their corresponding CUDs are committed to disk, their situation
* is very similar to being pinned. Return XFS_ITEM_PINNED so that the caller
* will eventually flush the log. This should help in getting the CUI out of
* the AIL.
*/
STATIC uint
xfs_cui_item_push(
struct xfs_log_item *lip,
struct list_head *buffer_list)
{
return XFS_ITEM_PINNED;
}
/*
* The CUI has been either committed or aborted if the transaction has been
* cancelled. If the transaction was cancelled, an CUD isn't going to be
* constructed and thus we free the CUI here directly.
*/
STATIC void
xfs_cui_item_unlock(
struct xfs_log_item *lip)
{
if (lip->li_flags & XFS_LI_ABORTED)
xfs_cui_item_free(CUI_ITEM(lip));
}
/*
* The CUI 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_cui_item_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
return lsn;
}
/*
* The CUI dependency tracking op doesn't do squat. It can't because
* it doesn't know where the free extent is coming from. The dependency
* tracking has to be handled by the "enclosing" metadata object. For
* example, for inodes, the inode is locked throughout the extent freeing
* so the dependency should be recorded there.
*/
STATIC void
xfs_cui_item_committing(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
}
/*
* This is the ops vector shared by all cui log items.
*/
static const struct xfs_item_ops xfs_cui_item_ops = {
.iop_size = xfs_cui_item_size,
.iop_format = xfs_cui_item_format,
.iop_pin = xfs_cui_item_pin,
.iop_unpin = xfs_cui_item_unpin,
.iop_unlock = xfs_cui_item_unlock,
.iop_committed = xfs_cui_item_committed,
.iop_push = xfs_cui_item_push,
.iop_committing = xfs_cui_item_committing,
};
/*
* Allocate and initialize an cui item with the given number of extents.
*/
struct xfs_cui_log_item *
xfs_cui_init(
struct xfs_mount *mp,
uint nextents)
{
struct xfs_cui_log_item *cuip;
ASSERT(nextents > 0);
if (nextents > XFS_CUI_MAX_FAST_EXTENTS)
cuip = kmem_zalloc(xfs_cui_log_item_sizeof(nextents),
KM_SLEEP);
else
cuip = kmem_zone_zalloc(xfs_cui_zone, KM_SLEEP);
xfs_log_item_init(mp, &cuip->cui_item, XFS_LI_CUI, &xfs_cui_item_ops);
cuip->cui_format.cui_nextents = nextents;
cuip->cui_format.cui_id = (uintptr_t)(void *)cuip;
atomic_set(&cuip->cui_next_extent, 0);
atomic_set(&cuip->cui_refcount, 2);
return cuip;
}
/*
* Freeing the CUI requires that we remove it from the AIL if it has already
* been placed there. However, the CUI may not yet have been placed in the AIL
* when called by xfs_cui_release() from CUD processing due to the ordering of
* committed vs unpin operations in bulk insert operations. Hence the reference
* count to ensure only the last caller frees the CUI.
*/
void
xfs_cui_release(
struct xfs_cui_log_item *cuip)
{
if (atomic_dec_and_test(&cuip->cui_refcount)) {
xfs_trans_ail_remove(&cuip->cui_item, SHUTDOWN_LOG_IO_ERROR);
xfs_cui_item_free(cuip);
}
}
static inline struct xfs_cud_log_item *CUD_ITEM(struct xfs_log_item *lip)
{
return container_of(lip, struct xfs_cud_log_item, cud_item);
}
STATIC void
xfs_cud_item_size(
struct xfs_log_item *lip,
int *nvecs,
int *nbytes)
{
*nvecs += 1;
*nbytes += sizeof(struct xfs_cud_log_format);
}
/*
* This is called to fill in the vector of log iovecs for the
* given cud log item. We use only 1 iovec, and we point that
* at the cud_log_format structure embedded in the cud item.
* It is at this point that we assert that all of the extent
* slots in the cud item have been filled.
*/
STATIC void
xfs_cud_item_format(
struct xfs_log_item *lip,
struct xfs_log_vec *lv)
{
struct xfs_cud_log_item *cudp = CUD_ITEM(lip);
struct xfs_log_iovec *vecp = NULL;
cudp->cud_format.cud_type = XFS_LI_CUD;
cudp->cud_format.cud_size = 1;
xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUD_FORMAT, &cudp->cud_format,
sizeof(struct xfs_cud_log_format));
}
/*
* Pinning has no meaning for an cud item, so just return.
*/
STATIC void
xfs_cud_item_pin(
struct xfs_log_item *lip)
{
}
/*
* Since pinning has no meaning for an cud item, unpinning does
* not either.
*/
STATIC void
xfs_cud_item_unpin(
struct xfs_log_item *lip,
int remove)
{
}
/*
* There isn't much you can do to push on an cud item. It is simply stuck
* waiting for the log to be flushed to disk.
*/
STATIC uint
xfs_cud_item_push(
struct xfs_log_item *lip,
struct list_head *buffer_list)
{
return XFS_ITEM_PINNED;
}
/*
* The CUD is either committed or aborted if the transaction is cancelled. If
* the transaction is cancelled, drop our reference to the CUI and free the
* CUD.
*/
STATIC void
xfs_cud_item_unlock(
struct xfs_log_item *lip)
{
struct xfs_cud_log_item *cudp = CUD_ITEM(lip);
if (lip->li_flags & XFS_LI_ABORTED) {
xfs_cui_release(cudp->cud_cuip);
kmem_zone_free(xfs_cud_zone, cudp);
}
}
/*
* When the cud item is committed to disk, all we need to do is delete our
* reference to our partner cui item and then free ourselves. Since we're
* freeing ourselves we must return -1 to keep the transaction code from
* further referencing this item.
*/
STATIC xfs_lsn_t
xfs_cud_item_committed(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
struct xfs_cud_log_item *cudp = CUD_ITEM(lip);
/*
* Drop the CUI reference regardless of whether the CUD has been
* aborted. Once the CUD transaction is constructed, it is the sole
* responsibility of the CUD to release the CUI (even if the CUI is
* aborted due to log I/O error).
*/
xfs_cui_release(cudp->cud_cuip);
kmem_zone_free(xfs_cud_zone, cudp);
return (xfs_lsn_t)-1;
}
/*
* The CUD dependency tracking op doesn't do squat. It can't because
* it doesn't know where the free extent is coming from. The dependency
* tracking has to be handled by the "enclosing" metadata object. For
* example, for inodes, the inode is locked throughout the extent freeing
* so the dependency should be recorded there.
*/
STATIC void
xfs_cud_item_committing(
struct xfs_log_item *lip,
xfs_lsn_t lsn)
{
}
/*
* This is the ops vector shared by all cud log items.
*/
static const struct xfs_item_ops xfs_cud_item_ops = {
.iop_size = xfs_cud_item_size,
.iop_format = xfs_cud_item_format,
.iop_pin = xfs_cud_item_pin,
.iop_unpin = xfs_cud_item_unpin,
.iop_unlock = xfs_cud_item_unlock,
.iop_committed = xfs_cud_item_committed,
.iop_push = xfs_cud_item_push,
.iop_committing = xfs_cud_item_committing,
};
/*
* Allocate and initialize an cud item with the given number of extents.
*/
struct xfs_cud_log_item *
xfs_cud_init(
struct xfs_mount *mp,
struct xfs_cui_log_item *cuip)
{
struct xfs_cud_log_item *cudp;
cudp = kmem_zone_zalloc(xfs_cud_zone, KM_SLEEP);
xfs_log_item_init(mp, &cudp->cud_item, XFS_LI_CUD, &xfs_cud_item_ops);
cudp->cud_cuip = cuip;
cudp->cud_format.cud_cui_id = cuip->cui_format.cui_id;
return cudp;
}