linux_dsm_epyc7002/fs/xfs/xfs_buf.h
Dave Chinner de1cbee462 xfs: kill b_file_offset
Seeing as we pass block numbers around everywhere in the buffer
cache now, it makes no sense to index everything by byte offset.
Replace all the byte offset indexing with block number based
indexing, and replace all uses of the byte offset with direct
conversion from the block index.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:46 -05:00

281 lines
9.8 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
*/
#ifndef __XFS_BUF_H__
#define __XFS_BUF_H__
#include <linux/list.h>
#include <linux/types.h>
#include <linux/spinlock.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;
#define XBF_READ (1 << 0) /* buffer intended for reading from device */
#define XBF_WRITE (1 << 1) /* buffer intended for writing to device */
#define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */
#define XBF_MAPPED (1 << 3) /* buffer mapped (b_addr valid) */
#define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */
#define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */
#define XBF_STALE (1 << 6) /* buffer has been staled, do not find it */
/* I/O hints for the BIO layer */
#define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */
#define XBF_FUA (1 << 11)/* force cache write through mode */
#define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */
/* flags used only as arguments to access routines */
#define XBF_LOCK (1 << 15)/* lock requested */
#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
#define XBF_DONT_BLOCK (1 << 17)/* do not block in current thread */
/* flags used only internally */
#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
#define _XBF_KMEM (1 << 21)/* backed by heap memory */
#define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */
typedef unsigned int xfs_buf_flags_t;
#define XFS_BUF_FLAGS \
{ XBF_READ, "READ" }, \
{ XBF_WRITE, "WRITE" }, \
{ XBF_READ_AHEAD, "READ_AHEAD" }, \
{ XBF_MAPPED, "MAPPED" }, \
{ XBF_ASYNC, "ASYNC" }, \
{ XBF_DONE, "DONE" }, \
{ XBF_STALE, "STALE" }, \
{ XBF_SYNCIO, "SYNCIO" }, \
{ XBF_FUA, "FUA" }, \
{ XBF_FLUSH, "FLUSH" }, \
{ XBF_LOCK, "LOCK" }, /* should never be set */\
{ XBF_TRYLOCK, "TRYLOCK" }, /* ditto */\
{ XBF_DONT_BLOCK, "DONT_BLOCK" }, /* ditto */\
{ _XBF_PAGES, "PAGES" }, \
{ _XBF_KMEM, "KMEM" }, \
{ _XBF_DELWRI_Q, "DELWRI_Q" }
typedef struct xfs_buftarg {
dev_t bt_dev;
struct block_device *bt_bdev;
struct backing_dev_info *bt_bdi;
struct xfs_mount *bt_mount;
unsigned int bt_bsize;
unsigned int bt_sshift;
size_t bt_smask;
/* LRU control structures */
struct shrinker bt_shrinker;
struct list_head bt_lru;
spinlock_t bt_lru_lock;
unsigned int bt_lru_nr;
} xfs_buftarg_t;
struct xfs_buf;
typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);
#define XB_PAGES 2
typedef struct xfs_buf {
/*
* first cacheline holds all the fields needed for an uncontended cache
* hit to be fully processed. The semaphore straddles the cacheline
* boundary, but the counter and lock sits on the first cacheline,
* which is the only bit that is touched if we hit the semaphore
* fast-path on locking.
*/
struct rb_node b_rbnode; /* rbtree node */
xfs_daddr_t b_bn; /* block number for I/O */
size_t b_buffer_length;/* size of buffer in bytes */
atomic_t b_hold; /* reference count */
atomic_t b_lru_ref; /* lru reclaim ref count */
xfs_buf_flags_t b_flags; /* status flags */
struct semaphore b_sema; /* semaphore for lockables */
struct list_head b_lru; /* lru list */
wait_queue_head_t b_waiters; /* unpin waiters */
struct list_head b_list;
struct xfs_perag *b_pag; /* contains rbtree root */
xfs_buftarg_t *b_target; /* buffer target (device) */
size_t b_count_desired;/* desired transfer size */
void *b_addr; /* virtual address of buffer */
struct work_struct b_iodone_work;
xfs_buf_iodone_t b_iodone; /* I/O completion function */
struct completion b_iowait; /* queue for I/O waiters */
void *b_fspriv;
struct xfs_trans *b_transp;
struct page **b_pages; /* array of page pointers */
struct page *b_page_array[XB_PAGES]; /* inline pages */
atomic_t b_pin_count; /* pin count */
atomic_t b_io_remaining; /* #outstanding I/O requests */
unsigned int b_page_count; /* size of page array */
unsigned int b_offset; /* page offset in first page */
unsigned short b_error; /* error code on I/O */
#ifdef XFS_BUF_LOCK_TRACKING
int b_last_holder;
#endif
} xfs_buf_t;
/* Finding and Reading Buffers */
struct xfs_buf *_xfs_buf_find(struct xfs_buftarg *target, xfs_daddr_t blkno,
size_t numblks, xfs_buf_flags_t flags,
struct xfs_buf *new_bp);
#define xfs_incore(buftarg,blkno,len,lockit) \
_xfs_buf_find(buftarg, blkno ,len, lockit, NULL)
struct xfs_buf *xfs_buf_get(struct xfs_buftarg *target, xfs_daddr_t blkno,
size_t numblks, xfs_buf_flags_t flags);
struct xfs_buf *xfs_buf_read(struct xfs_buftarg *target, xfs_daddr_t blkno,
size_t numblks, xfs_buf_flags_t flags);
void xfs_buf_readahead(struct xfs_buftarg *target, xfs_daddr_t blkno,
size_t numblks);
struct xfs_buf *xfs_buf_get_empty(struct xfs_buftarg *target, size_t numblks);
struct xfs_buf *xfs_buf_alloc(struct xfs_buftarg *target, xfs_daddr_t blkno,
size_t numblks, xfs_buf_flags_t flags);
void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks);
int xfs_buf_associate_memory(struct xfs_buf *bp, void *mem, size_t length);
struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks,
int flags);
struct xfs_buf *xfs_buf_read_uncached(struct xfs_buftarg *target,
xfs_daddr_t daddr, size_t numblks, int flags);
void xfs_buf_hold(struct xfs_buf *bp);
/* 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_trylock(xfs_buf_t *);
extern void xfs_buf_lock(xfs_buf_t *);
extern void xfs_buf_unlock(xfs_buf_t *);
#define xfs_buf_islocked(bp) \
((bp)->b_sema.count <= 0)
/* Buffer Read and Write Routines */
extern int xfs_bwrite(struct xfs_buf *bp);
extern void xfsbdstrat(struct xfs_mount *, struct xfs_buf *);
extern int xfs_bdstrat_cb(struct xfs_buf *);
extern void xfs_buf_ioend(xfs_buf_t *, int);
extern void xfs_buf_ioerror(xfs_buf_t *, int);
extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func);
extern void 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, void *,
xfs_buf_rw_t);
#define xfs_buf_zero(bp, off, len) \
xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
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);
/* Delayed Write Buffer Routines */
extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
extern int xfs_buf_delwri_submit(struct list_head *);
extern int xfs_buf_delwri_submit_nowait(struct list_head *);
/* Buffer Daemon Setup Routines */
extern int xfs_buf_init(void);
extern void xfs_buf_terminate(void);
#define XFS_BUF_ZEROFLAGS(bp) \
((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC| \
XBF_SYNCIO|XBF_FUA|XBF_FLUSH))
void xfs_buf_stale(struct xfs_buf *bp);
#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE)
#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_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_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_ADDR(bp) ((bp)->b_bn)
#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_bn = (xfs_daddr_t)(bno))
#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))
static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref)
{
atomic_set(&bp->b_lru_ref, lru_ref);
}
static inline int xfs_buf_ispinned(struct xfs_buf *bp)
{
return atomic_read(&bp->b_pin_count);
}
static inline void xfs_buf_relse(xfs_buf_t *bp)
{
xfs_buf_unlock(bp);
xfs_buf_rele(bp);
}
/*
* Handling of buftargs.
*/
extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
struct block_device *, int, const char *);
extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
extern void xfs_wait_buftarg(xfs_buftarg_t *);
extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
#endif /* __XFS_BUF_H__ */