alistair23-linux/fs/xfs/xfs_trans.h
Brian Foster a5814bceea xfs: disallow marking previously dirty buffers as ordered
Ordered buffers are used in situations where the buffer is not
physically logged but must pass through the transaction/logging
pipeline for a particular transaction. As a result, ordered buffers
are not unpinned and written back until the transaction commits to
the log. Ordered buffers have a strict requirement that the target
buffer must not be currently dirty and resident in the log pipeline
at the time it is marked ordered. If a dirty+ordered buffer is
committed, the buffer is reinserted to the AIL but not physically
relogged at the LSN of the associated checkpoint. The buffer log
item is assigned the LSN of the latest checkpoint and the AIL
effectively releases the previously logged buffer content from the
active log before the buffer has been written back. If the tail
pushes forward and a filesystem crash occurs while in this state, an
inconsistent filesystem could result.

It is currently the caller responsibility to ensure an ordered
buffer is not already dirty from a previous modification. This is
unclear and error prone when not used in situations where it is
guaranteed a buffer has not been previously modified (such as new
metadata allocations).

To facilitate general purpose use of ordered buffers, update
xfs_trans_ordered_buf() to conditionally order the buffer based on
state of the log item and return the status of the result. If the
bli is dirty, do not order the buffer and return false. The caller
must either physically log the buffer (having acquired the
appropriate log reservation) or push it from the AIL to clean it
before it can be marked ordered in the current transaction.

Note that ordered buffers are currently only used in two situations:
1.) inode chunk allocation where previously logged buffers are not
possible and 2.) extent swap which will be updated to handle ordered
buffer failures in a separate patch.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-09-01 10:55:30 -07:00

284 lines
10 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
*/
#ifndef __XFS_TRANS_H__
#define __XFS_TRANS_H__
/* kernel only transaction subsystem defines */
struct xfs_buf;
struct xfs_buftarg;
struct xfs_efd_log_item;
struct xfs_efi_log_item;
struct xfs_inode;
struct xfs_item_ops;
struct xfs_log_iovec;
struct xfs_log_item_desc;
struct xfs_mount;
struct xfs_trans;
struct xfs_trans_res;
struct xfs_dquot_acct;
struct xfs_rud_log_item;
struct xfs_rui_log_item;
struct xfs_btree_cur;
struct xfs_cui_log_item;
struct xfs_cud_log_item;
struct xfs_defer_ops;
struct xfs_bui_log_item;
struct xfs_bud_log_item;
typedef struct xfs_log_item {
struct list_head li_ail; /* AIL pointers */
xfs_lsn_t li_lsn; /* last on-disk lsn */
struct xfs_log_item_desc *li_desc; /* ptr to current desc*/
struct xfs_mount *li_mountp; /* ptr to fs mount */
struct xfs_ail *li_ailp; /* ptr to AIL */
uint li_type; /* item type */
uint li_flags; /* misc flags */
struct xfs_buf *li_buf; /* real buffer pointer */
struct xfs_log_item *li_bio_list; /* buffer item list */
void (*li_cb)(struct xfs_buf *,
struct xfs_log_item *);
/* buffer item iodone */
/* callback func */
const struct xfs_item_ops *li_ops; /* function list */
/* delayed logging */
struct list_head li_cil; /* CIL pointers */
struct xfs_log_vec *li_lv; /* active log vector */
struct xfs_log_vec *li_lv_shadow; /* standby vector */
xfs_lsn_t li_seq; /* CIL commit seq */
} xfs_log_item_t;
#define XFS_LI_IN_AIL 0x1
#define XFS_LI_ABORTED 0x2
#define XFS_LI_FAILED 0x4
#define XFS_LI_FLAGS \
{ XFS_LI_IN_AIL, "IN_AIL" }, \
{ XFS_LI_ABORTED, "ABORTED" }, \
{ XFS_LI_FAILED, "FAILED" }
struct xfs_item_ops {
void (*iop_size)(xfs_log_item_t *, int *, int *);
void (*iop_format)(xfs_log_item_t *, struct xfs_log_vec *);
void (*iop_pin)(xfs_log_item_t *);
void (*iop_unpin)(xfs_log_item_t *, int remove);
uint (*iop_push)(struct xfs_log_item *, struct list_head *);
void (*iop_unlock)(xfs_log_item_t *);
xfs_lsn_t (*iop_committed)(xfs_log_item_t *, xfs_lsn_t);
void (*iop_committing)(xfs_log_item_t *, xfs_lsn_t);
void (*iop_error)(xfs_log_item_t *, xfs_buf_t *);
};
void xfs_log_item_init(struct xfs_mount *mp, struct xfs_log_item *item,
int type, const struct xfs_item_ops *ops);
/*
* Return values for the iop_push() routines.
*/
#define XFS_ITEM_SUCCESS 0
#define XFS_ITEM_PINNED 1
#define XFS_ITEM_LOCKED 2
#define XFS_ITEM_FLUSHING 3
/*
* This is the structure maintained for every active transaction.
*/
typedef struct xfs_trans {
unsigned int t_magic; /* magic number */
unsigned int t_log_res; /* amt of log space resvd */
unsigned int t_log_count; /* count for perm log res */
unsigned int t_blk_res; /* # of blocks resvd */
unsigned int t_blk_res_used; /* # of resvd blocks used */
unsigned int t_rtx_res; /* # of rt extents resvd */
unsigned int t_rtx_res_used; /* # of resvd rt extents used */
struct xlog_ticket *t_ticket; /* log mgr ticket */
struct xfs_mount *t_mountp; /* ptr to fs mount struct */
struct xfs_dquot_acct *t_dqinfo; /* acctg info for dquots */
unsigned int t_flags; /* misc flags */
int64_t t_icount_delta; /* superblock icount change */
int64_t t_ifree_delta; /* superblock ifree change */
int64_t t_fdblocks_delta; /* superblock fdblocks chg */
int64_t t_res_fdblocks_delta; /* on-disk only chg */
int64_t t_frextents_delta;/* superblock freextents chg*/
int64_t t_res_frextents_delta; /* on-disk only chg */
#if defined(DEBUG) || defined(XFS_WARN)
int64_t t_ag_freeblks_delta; /* debugging counter */
int64_t t_ag_flist_delta; /* debugging counter */
int64_t t_ag_btree_delta; /* debugging counter */
#endif
int64_t t_dblocks_delta;/* superblock dblocks change */
int64_t t_agcount_delta;/* superblock agcount change */
int64_t t_imaxpct_delta;/* superblock imaxpct change */
int64_t t_rextsize_delta;/* superblock rextsize chg */
int64_t t_rbmblocks_delta;/* superblock rbmblocks chg */
int64_t t_rblocks_delta;/* superblock rblocks change */
int64_t t_rextents_delta;/* superblocks rextents chg */
int64_t t_rextslog_delta;/* superblocks rextslog chg */
struct list_head t_items; /* log item descriptors */
struct list_head t_busy; /* list of busy extents */
unsigned long t_pflags; /* saved process flags state */
} xfs_trans_t;
/*
* XFS transaction mechanism exported interfaces that are
* actually macros.
*/
#define xfs_trans_set_sync(tp) ((tp)->t_flags |= XFS_TRANS_SYNC)
#if defined(DEBUG) || defined(XFS_WARN)
#define xfs_trans_agblocks_delta(tp, d) ((tp)->t_ag_freeblks_delta += (int64_t)d)
#define xfs_trans_agflist_delta(tp, d) ((tp)->t_ag_flist_delta += (int64_t)d)
#define xfs_trans_agbtree_delta(tp, d) ((tp)->t_ag_btree_delta += (int64_t)d)
#else
#define xfs_trans_agblocks_delta(tp, d)
#define xfs_trans_agflist_delta(tp, d)
#define xfs_trans_agbtree_delta(tp, d)
#endif
/*
* XFS transaction mechanism exported interfaces.
*/
int xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
uint blocks, uint rtextents, uint flags,
struct xfs_trans **tpp);
int xfs_trans_alloc_empty(struct xfs_mount *mp,
struct xfs_trans **tpp);
void xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);
struct xfs_buf *xfs_trans_get_buf_map(struct xfs_trans *tp,
struct xfs_buftarg *target,
struct xfs_buf_map *map, int nmaps,
uint flags);
static inline struct xfs_buf *
xfs_trans_get_buf(
struct xfs_trans *tp,
struct xfs_buftarg *target,
xfs_daddr_t blkno,
int numblks,
uint flags)
{
DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
return xfs_trans_get_buf_map(tp, target, &map, 1, flags);
}
int xfs_trans_read_buf_map(struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_buftarg *target,
struct xfs_buf_map *map, int nmaps,
xfs_buf_flags_t flags,
struct xfs_buf **bpp,
const struct xfs_buf_ops *ops);
static inline int
xfs_trans_read_buf(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_buftarg *target,
xfs_daddr_t blkno,
int numblks,
xfs_buf_flags_t flags,
struct xfs_buf **bpp,
const struct xfs_buf_ops *ops)
{
DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
return xfs_trans_read_buf_map(mp, tp, target, &map, 1,
flags, bpp, ops);
}
struct xfs_buf *xfs_trans_getsb(xfs_trans_t *, struct xfs_mount *, int);
void xfs_trans_brelse(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_bjoin(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_bhold(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_bhold_release(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_binval(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_inode_buf(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_stale_inode_buf(xfs_trans_t *, struct xfs_buf *);
bool xfs_trans_ordered_buf(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint);
void xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *);
void xfs_trans_ichgtime(struct xfs_trans *, struct xfs_inode *, int);
void xfs_trans_ijoin(struct xfs_trans *, struct xfs_inode *, uint);
void xfs_trans_log_buf(struct xfs_trans *, struct xfs_buf *, uint,
uint);
void xfs_trans_dirty_buf(struct xfs_trans *, struct xfs_buf *);
void xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint);
void xfs_extent_free_init_defer_op(void);
struct xfs_efd_log_item *xfs_trans_get_efd(struct xfs_trans *,
struct xfs_efi_log_item *,
uint);
int xfs_trans_free_extent(struct xfs_trans *,
struct xfs_efd_log_item *, xfs_fsblock_t,
xfs_extlen_t, struct xfs_owner_info *);
int xfs_trans_commit(struct xfs_trans *);
int xfs_trans_roll(struct xfs_trans **);
int xfs_trans_roll_inode(struct xfs_trans **, struct xfs_inode *);
void xfs_trans_cancel(xfs_trans_t *);
int xfs_trans_ail_init(struct xfs_mount *);
void xfs_trans_ail_destroy(struct xfs_mount *);
void xfs_trans_buf_set_type(struct xfs_trans *, struct xfs_buf *,
enum xfs_blft);
void xfs_trans_buf_copy_type(struct xfs_buf *dst_bp,
struct xfs_buf *src_bp);
extern kmem_zone_t *xfs_trans_zone;
extern kmem_zone_t *xfs_log_item_desc_zone;
/* rmap updates */
enum xfs_rmap_intent_type;
void xfs_rmap_update_init_defer_op(void);
struct xfs_rud_log_item *xfs_trans_get_rud(struct xfs_trans *tp,
struct xfs_rui_log_item *ruip);
int xfs_trans_log_finish_rmap_update(struct xfs_trans *tp,
struct xfs_rud_log_item *rudp, enum xfs_rmap_intent_type type,
uint64_t owner, int whichfork, xfs_fileoff_t startoff,
xfs_fsblock_t startblock, xfs_filblks_t blockcount,
xfs_exntst_t state, struct xfs_btree_cur **pcur);
/* refcount updates */
enum xfs_refcount_intent_type;
void xfs_refcount_update_init_defer_op(void);
struct xfs_cud_log_item *xfs_trans_get_cud(struct xfs_trans *tp,
struct xfs_cui_log_item *cuip);
int xfs_trans_log_finish_refcount_update(struct xfs_trans *tp,
struct xfs_cud_log_item *cudp, struct xfs_defer_ops *dfops,
enum xfs_refcount_intent_type type, xfs_fsblock_t startblock,
xfs_extlen_t blockcount, xfs_fsblock_t *new_fsb,
xfs_extlen_t *new_len, struct xfs_btree_cur **pcur);
/* mapping updates */
enum xfs_bmap_intent_type;
void xfs_bmap_update_init_defer_op(void);
struct xfs_bud_log_item *xfs_trans_get_bud(struct xfs_trans *tp,
struct xfs_bui_log_item *buip);
int xfs_trans_log_finish_bmap_update(struct xfs_trans *tp,
struct xfs_bud_log_item *rudp, struct xfs_defer_ops *dfops,
enum xfs_bmap_intent_type type, struct xfs_inode *ip,
int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
xfs_filblks_t *blockcount, xfs_exntst_t state);
#endif /* __XFS_TRANS_H__ */