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linux-next/fs/xfs/linux-2.6/xfs_buf.h
Christoph Hellwig 73f6aa4d44 Fix barrier fail detection in XFS
Currently we disable barriers as soon as we get a buffer in xlog_iodone
that has the XBF_ORDERED flag cleared.  But this can be the case not only
for buffers where the barrier failed, but also the first buffer of a
split log write in case of a log wraparound.  Due to the disabled
barriers we can easily get directory corruption on unclean shutdowns.
So instead of using this check add a new buffer flag for failed barrier
writes.

This is a regression vs 2.6.26 caused by patch to use the right macro
to check for the ORDERED flag, as we previously got true returned for
every buffer.

Thanks to Toei Rei for reporting the bug.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: David Chinner <david@fromorbit.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-10 11:08:07 -07:00

455 lines
16 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
*/
#ifndef __XFS_BUF_H__
#define __XFS_BUF_H__
#include <linux/list.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <asm/system.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/uio.h>
/*
* Base types
*/
#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
#define xfs_buf_ctob(pp) ((pp) * PAGE_CACHE_SIZE)
#define xfs_buf_btoc(dd) (((dd) + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT)
#define xfs_buf_btoct(dd) ((dd) >> PAGE_CACHE_SHIFT)
#define xfs_buf_poff(aa) ((aa) & ~PAGE_CACHE_MASK)
typedef enum {
XBRW_READ = 1, /* transfer into target memory */
XBRW_WRITE = 2, /* transfer from target memory */
XBRW_ZERO = 3, /* Zero target memory */
} xfs_buf_rw_t;
typedef enum {
XBF_READ = (1 << 0), /* buffer intended for reading from device */
XBF_WRITE = (1 << 1), /* buffer intended for writing to device */
XBF_MAPPED = (1 << 2), /* buffer mapped (b_addr valid) */
XBF_ASYNC = (1 << 4), /* initiator will not wait for completion */
XBF_DONE = (1 << 5), /* all pages in the buffer uptodate */
XBF_DELWRI = (1 << 6), /* buffer has dirty pages */
XBF_STALE = (1 << 7), /* buffer has been staled, do not find it */
XBF_FS_MANAGED = (1 << 8), /* filesystem controls freeing memory */
XBF_ORDERED = (1 << 11), /* use ordered writes */
XBF_READ_AHEAD = (1 << 12), /* asynchronous read-ahead */
/* flags used only as arguments to access routines */
XBF_LOCK = (1 << 14), /* lock requested */
XBF_TRYLOCK = (1 << 15), /* lock requested, but do not wait */
XBF_DONT_BLOCK = (1 << 16), /* do not block in current thread */
/* flags used only internally */
_XBF_PAGE_CACHE = (1 << 17),/* backed by pagecache */
_XBF_PAGES = (1 << 18), /* backed by refcounted pages */
_XBF_RUN_QUEUES = (1 << 19),/* run block device task queue */
_XBF_DELWRI_Q = (1 << 21), /* buffer on delwri queue */
/*
* Special flag for supporting metadata blocks smaller than a FSB.
*
* In this case we can have multiple xfs_buf_t on a single page and
* need to lock out concurrent xfs_buf_t readers as they only
* serialise access to the buffer.
*
* If the FSB size >= PAGE_CACHE_SIZE case, we have no serialisation
* between reads of the page. Hence we can have one thread read the
* page and modify it, but then race with another thread that thinks
* the page is not up-to-date and hence reads it again.
*
* The result is that the first modifcation to the page is lost.
* This sort of AGF/AGI reading race can happen when unlinking inodes
* that require truncation and results in the AGI unlinked list
* modifications being lost.
*/
_XBF_PAGE_LOCKED = (1 << 22),
/*
* If we try a barrier write, but it fails we have to communicate
* this to the upper layers. Unfortunately b_error gets overwritten
* when the buffer is re-issued so we have to add another flag to
* keep this information.
*/
_XFS_BARRIER_FAILED = (1 << 23),
} xfs_buf_flags_t;
typedef enum {
XBT_FORCE_SLEEP = 0,
XBT_FORCE_FLUSH = 1,
} xfs_buftarg_flags_t;
typedef struct xfs_bufhash {
struct list_head bh_list;
spinlock_t bh_lock;
} xfs_bufhash_t;
typedef struct xfs_buftarg {
dev_t bt_dev;
struct block_device *bt_bdev;
struct address_space *bt_mapping;
unsigned int bt_bsize;
unsigned int bt_sshift;
size_t bt_smask;
/* per device buffer hash table */
uint bt_hashmask;
uint bt_hashshift;
xfs_bufhash_t *bt_hash;
/* per device delwri queue */
struct task_struct *bt_task;
struct list_head bt_list;
struct list_head bt_delwrite_queue;
spinlock_t bt_delwrite_lock;
unsigned long bt_flags;
} xfs_buftarg_t;
/*
* xfs_buf_t: Buffer structure for pagecache-based buffers
*
* This buffer structure is used by the pagecache buffer management routines
* to refer to an assembly of pages forming a logical buffer.
*
* The buffer structure is used on a temporary basis only, and discarded when
* released. The real data storage is recorded in the pagecache. Buffers are
* hashed to the block device on which the file system resides.
*/
struct xfs_buf;
typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);
typedef void (*xfs_buf_relse_t)(struct xfs_buf *);
typedef int (*xfs_buf_bdstrat_t)(struct xfs_buf *);
#define XB_PAGES 2
typedef struct xfs_buf {
struct semaphore b_sema; /* semaphore for lockables */
unsigned long b_queuetime; /* time buffer was queued */
atomic_t b_pin_count; /* pin count */
wait_queue_head_t b_waiters; /* unpin waiters */
struct list_head b_list;
xfs_buf_flags_t b_flags; /* status flags */
struct list_head b_hash_list; /* hash table list */
xfs_bufhash_t *b_hash; /* hash table list start */
xfs_buftarg_t *b_target; /* buffer target (device) */
atomic_t b_hold; /* reference count */
xfs_daddr_t b_bn; /* block number for I/O */
xfs_off_t b_file_offset; /* offset in file */
size_t b_buffer_length;/* size of buffer in bytes */
size_t b_count_desired;/* desired transfer size */
void *b_addr; /* virtual address of buffer */
struct work_struct b_iodone_work;
atomic_t b_io_remaining; /* #outstanding I/O requests */
xfs_buf_iodone_t b_iodone; /* I/O completion function */
xfs_buf_relse_t b_relse; /* releasing function */
xfs_buf_bdstrat_t b_strat; /* pre-write function */
struct completion b_iowait; /* queue for I/O waiters */
void *b_fspriv;
void *b_fspriv2;
void *b_fspriv3;
unsigned short b_error; /* error code on I/O */
unsigned int b_page_count; /* size of page array */
unsigned int b_offset; /* page offset in first page */
struct page **b_pages; /* array of page pointers */
struct page *b_page_array[XB_PAGES]; /* inline pages */
#ifdef XFS_BUF_LOCK_TRACKING
int b_last_holder;
#endif
} xfs_buf_t;
/* Finding and Reading Buffers */
extern xfs_buf_t *_xfs_buf_find(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t, xfs_buf_t *);
#define xfs_incore(buftarg,blkno,len,lockit) \
_xfs_buf_find(buftarg, blkno ,len, lockit, NULL)
extern xfs_buf_t *xfs_buf_get_flags(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t);
#define xfs_buf_get(target, blkno, len, flags) \
xfs_buf_get_flags((target), (blkno), (len), XBF_LOCK | XBF_MAPPED)
extern xfs_buf_t *xfs_buf_read_flags(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t);
#define xfs_buf_read(target, blkno, len, flags) \
xfs_buf_read_flags((target), (blkno), (len), XBF_LOCK | XBF_MAPPED)
extern xfs_buf_t *xfs_buf_get_empty(size_t, xfs_buftarg_t *);
extern xfs_buf_t *xfs_buf_get_noaddr(size_t, xfs_buftarg_t *);
extern int xfs_buf_associate_memory(xfs_buf_t *, void *, size_t);
extern void xfs_buf_hold(xfs_buf_t *);
extern void xfs_buf_readahead(xfs_buftarg_t *, xfs_off_t, size_t,
xfs_buf_flags_t);
/* Releasing Buffers */
extern void xfs_buf_free(xfs_buf_t *);
extern void xfs_buf_rele(xfs_buf_t *);
/* Locking and Unlocking Buffers */
extern int xfs_buf_cond_lock(xfs_buf_t *);
extern int xfs_buf_lock_value(xfs_buf_t *);
extern void xfs_buf_lock(xfs_buf_t *);
extern void xfs_buf_unlock(xfs_buf_t *);
/* Buffer Read and Write Routines */
extern void xfs_buf_ioend(xfs_buf_t *, int);
extern void xfs_buf_ioerror(xfs_buf_t *, int);
extern int xfs_buf_iostart(xfs_buf_t *, xfs_buf_flags_t);
extern int xfs_buf_iorequest(xfs_buf_t *);
extern int xfs_buf_iowait(xfs_buf_t *);
extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, xfs_caddr_t,
xfs_buf_rw_t);
static inline int xfs_buf_iostrategy(xfs_buf_t *bp)
{
return bp->b_strat ? bp->b_strat(bp) : xfs_buf_iorequest(bp);
}
static inline int xfs_buf_geterror(xfs_buf_t *bp)
{
return bp ? bp->b_error : ENOMEM;
}
/* Buffer Utility Routines */
extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);
/* Pinning Buffer Storage in Memory */
extern void xfs_buf_pin(xfs_buf_t *);
extern void xfs_buf_unpin(xfs_buf_t *);
extern int xfs_buf_ispin(xfs_buf_t *);
/* Delayed Write Buffer Routines */
extern void xfs_buf_delwri_dequeue(xfs_buf_t *);
/* Buffer Daemon Setup Routines */
extern int xfs_buf_init(void);
extern void xfs_buf_terminate(void);
#ifdef XFS_BUF_TRACE
extern ktrace_t *xfs_buf_trace_buf;
extern void xfs_buf_trace(xfs_buf_t *, char *, void *, void *);
#else
#define xfs_buf_trace(bp,id,ptr,ra) do { } while (0)
#endif
#define xfs_buf_target_name(target) \
({ char __b[BDEVNAME_SIZE]; bdevname((target)->bt_bdev, __b); __b; })
#define XFS_B_ASYNC XBF_ASYNC
#define XFS_B_DELWRI XBF_DELWRI
#define XFS_B_READ XBF_READ
#define XFS_B_WRITE XBF_WRITE
#define XFS_B_STALE XBF_STALE
#define XFS_BUF_TRYLOCK XBF_TRYLOCK
#define XFS_INCORE_TRYLOCK XBF_TRYLOCK
#define XFS_BUF_LOCK XBF_LOCK
#define XFS_BUF_MAPPED XBF_MAPPED
#define BUF_BUSY XBF_DONT_BLOCK
#define XFS_BUF_BFLAGS(bp) ((bp)->b_flags)
#define XFS_BUF_ZEROFLAGS(bp) ((bp)->b_flags &= \
~(XBF_READ|XBF_WRITE|XBF_ASYNC|XBF_DELWRI|XBF_ORDERED))
#define XFS_BUF_STALE(bp) ((bp)->b_flags |= XFS_B_STALE)
#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XFS_B_STALE)
#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XFS_B_STALE)
#define XFS_BUF_SUPER_STALE(bp) do { \
XFS_BUF_STALE(bp); \
xfs_buf_delwri_dequeue(bp); \
XFS_BUF_DONE(bp); \
} while (0)
#define XFS_BUF_MANAGE XBF_FS_MANAGED
#define XFS_BUF_UNMANAGE(bp) ((bp)->b_flags &= ~XBF_FS_MANAGED)
#define XFS_BUF_DELAYWRITE(bp) ((bp)->b_flags |= XBF_DELWRI)
#define XFS_BUF_UNDELAYWRITE(bp) xfs_buf_delwri_dequeue(bp)
#define XFS_BUF_ISDELAYWRITE(bp) ((bp)->b_flags & XBF_DELWRI)
#define XFS_BUF_ERROR(bp,no) xfs_buf_ioerror(bp,no)
#define XFS_BUF_GETERROR(bp) xfs_buf_geterror(bp)
#define XFS_BUF_ISERROR(bp) (xfs_buf_geterror(bp) ? 1 : 0)
#define XFS_BUF_DONE(bp) ((bp)->b_flags |= XBF_DONE)
#define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE)
#define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE)
#define XFS_BUF_BUSY(bp) do { } while (0)
#define XFS_BUF_UNBUSY(bp) do { } while (0)
#define XFS_BUF_ISBUSY(bp) (1)
#define XFS_BUF_ASYNC(bp) ((bp)->b_flags |= XBF_ASYNC)
#define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC)
#define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC)
#define XFS_BUF_ORDERED(bp) ((bp)->b_flags |= XBF_ORDERED)
#define XFS_BUF_UNORDERED(bp) ((bp)->b_flags &= ~XBF_ORDERED)
#define XFS_BUF_ISORDERED(bp) ((bp)->b_flags & XBF_ORDERED)
#define XFS_BUF_SHUT(bp) do { } while (0)
#define XFS_BUF_UNSHUT(bp) do { } while (0)
#define XFS_BUF_ISSHUT(bp) (0)
#define XFS_BUF_HOLD(bp) xfs_buf_hold(bp)
#define XFS_BUF_READ(bp) ((bp)->b_flags |= XBF_READ)
#define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ)
#define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ)
#define XFS_BUF_WRITE(bp) ((bp)->b_flags |= XBF_WRITE)
#define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE)
#define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE)
#define XFS_BUF_IODONE_FUNC(bp) ((bp)->b_iodone)
#define XFS_BUF_SET_IODONE_FUNC(bp, func) ((bp)->b_iodone = (func))
#define XFS_BUF_CLR_IODONE_FUNC(bp) ((bp)->b_iodone = NULL)
#define XFS_BUF_SET_BDSTRAT_FUNC(bp, func) ((bp)->b_strat = (func))
#define XFS_BUF_CLR_BDSTRAT_FUNC(bp) ((bp)->b_strat = NULL)
#define XFS_BUF_FSPRIVATE(bp, type) ((type)(bp)->b_fspriv)
#define XFS_BUF_SET_FSPRIVATE(bp, val) ((bp)->b_fspriv = (void*)(val))
#define XFS_BUF_FSPRIVATE2(bp, type) ((type)(bp)->b_fspriv2)
#define XFS_BUF_SET_FSPRIVATE2(bp, val) ((bp)->b_fspriv2 = (void*)(val))
#define XFS_BUF_FSPRIVATE3(bp, type) ((type)(bp)->b_fspriv3)
#define XFS_BUF_SET_FSPRIVATE3(bp, val) ((bp)->b_fspriv3 = (void*)(val))
#define XFS_BUF_SET_START(bp) do { } while (0)
#define XFS_BUF_SET_BRELSE_FUNC(bp, func) ((bp)->b_relse = (func))
#define XFS_BUF_PTR(bp) (xfs_caddr_t)((bp)->b_addr)
#define XFS_BUF_SET_PTR(bp, val, cnt) xfs_buf_associate_memory(bp, val, cnt)
#define XFS_BUF_ADDR(bp) ((bp)->b_bn)
#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_bn = (xfs_daddr_t)(bno))
#define XFS_BUF_OFFSET(bp) ((bp)->b_file_offset)
#define XFS_BUF_SET_OFFSET(bp, off) ((bp)->b_file_offset = (off))
#define XFS_BUF_COUNT(bp) ((bp)->b_count_desired)
#define XFS_BUF_SET_COUNT(bp, cnt) ((bp)->b_count_desired = (cnt))
#define XFS_BUF_SIZE(bp) ((bp)->b_buffer_length)
#define XFS_BUF_SET_SIZE(bp, cnt) ((bp)->b_buffer_length = (cnt))
#define XFS_BUF_SET_VTYPE_REF(bp, type, ref) do { } while (0)
#define XFS_BUF_SET_VTYPE(bp, type) do { } while (0)
#define XFS_BUF_SET_REF(bp, ref) do { } while (0)
#define XFS_BUF_ISPINNED(bp) xfs_buf_ispin(bp)
#define XFS_BUF_VALUSEMA(bp) xfs_buf_lock_value(bp)
#define XFS_BUF_CPSEMA(bp) (xfs_buf_cond_lock(bp) == 0)
#define XFS_BUF_VSEMA(bp) xfs_buf_unlock(bp)
#define XFS_BUF_PSEMA(bp,x) xfs_buf_lock(bp)
#define XFS_BUF_FINISH_IOWAIT(bp) complete(&bp->b_iowait);
#define XFS_BUF_SET_TARGET(bp, target) ((bp)->b_target = (target))
#define XFS_BUF_TARGET(bp) ((bp)->b_target)
#define XFS_BUFTARG_NAME(target) xfs_buf_target_name(target)
static inline int xfs_bawrite(void *mp, xfs_buf_t *bp)
{
bp->b_fspriv3 = mp;
bp->b_strat = xfs_bdstrat_cb;
xfs_buf_delwri_dequeue(bp);
return xfs_buf_iostart(bp, XBF_WRITE | XBF_ASYNC | _XBF_RUN_QUEUES);
}
static inline void xfs_buf_relse(xfs_buf_t *bp)
{
if (!bp->b_relse)
xfs_buf_unlock(bp);
xfs_buf_rele(bp);
}
#define xfs_bpin(bp) xfs_buf_pin(bp)
#define xfs_bunpin(bp) xfs_buf_unpin(bp)
#define xfs_buftrace(id, bp) \
xfs_buf_trace(bp, id, NULL, (void *)__builtin_return_address(0))
#define xfs_biodone(bp) xfs_buf_ioend(bp, 0)
#define xfs_biomove(bp, off, len, data, rw) \
xfs_buf_iomove((bp), (off), (len), (data), \
((rw) == XFS_B_WRITE) ? XBRW_WRITE : XBRW_READ)
#define xfs_biozero(bp, off, len) \
xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
static inline int XFS_bwrite(xfs_buf_t *bp)
{
int iowait = (bp->b_flags & XBF_ASYNC) == 0;
int error = 0;
if (!iowait)
bp->b_flags |= _XBF_RUN_QUEUES;
xfs_buf_delwri_dequeue(bp);
xfs_buf_iostrategy(bp);
if (iowait) {
error = xfs_buf_iowait(bp);
xfs_buf_relse(bp);
}
return error;
}
/*
* No error can be returned from xfs_buf_iostart for delwri
* buffers as they are queued and no I/O is issued.
*/
static inline void xfs_bdwrite(void *mp, xfs_buf_t *bp)
{
bp->b_strat = xfs_bdstrat_cb;
bp->b_fspriv3 = mp;
(void)xfs_buf_iostart(bp, XBF_DELWRI | XBF_ASYNC);
}
#define XFS_bdstrat(bp) xfs_buf_iorequest(bp)
#define xfs_iowait(bp) xfs_buf_iowait(bp)
#define xfs_baread(target, rablkno, ralen) \
xfs_buf_readahead((target), (rablkno), (ralen), XBF_DONT_BLOCK)
/*
* Handling of buftargs.
*/
extern xfs_buftarg_t *xfs_alloc_buftarg(struct block_device *, int);
extern void xfs_free_buftarg(xfs_buftarg_t *);
extern void xfs_wait_buftarg(xfs_buftarg_t *);
extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
extern int xfs_flush_buftarg(xfs_buftarg_t *, int);
#ifdef CONFIG_KDB_MODULES
extern struct list_head *xfs_get_buftarg_list(void);
#endif
#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
#define xfs_binval(buftarg) xfs_flush_buftarg(buftarg, 1)
#define XFS_bflush(buftarg) xfs_flush_buftarg(buftarg, 1)
#endif /* __XFS_BUF_H__ */