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-rw-r--r--fs/xfs/xfs_buf.h326
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diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
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+++ b/fs/xfs/xfs_buf.h
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+/*
+ * 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;
+
+#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_DELWRI (1 << 6) /* buffer has dirty pages */
+#define XBF_STALE (1 << 7) /* 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 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_DELWRI, "DELWRI" }, \
+ { 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 enum {
+ XBT_FORCE_SLEEP = 0,
+ XBT_FORCE_FLUSH = 1,
+} xfs_buftarg_flags_t;
+
+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;
+
+ /* per device delwri queue */
+ struct task_struct *bt_task;
+ struct list_head bt_delwrite_queue;
+ spinlock_t bt_delwrite_lock;
+ unsigned long bt_flags;
+
+ /* 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_off_t b_file_offset; /* offset in file */
+ 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) */
+ xfs_daddr_t b_bn; /* block number for I/O */
+ 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 */
+ unsigned long b_queuetime; /* time buffer was queued */
+ 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 */
+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(xfs_buftarg_t *, xfs_off_t, size_t,
+ xfs_buf_flags_t);
+extern xfs_buf_t *xfs_buf_read(xfs_buftarg_t *, xfs_off_t, size_t,
+ xfs_buf_flags_t);
+
+extern xfs_buf_t *xfs_buf_get_empty(size_t, xfs_buftarg_t *);
+extern void xfs_buf_set_empty(struct xfs_buf *bp, size_t len);
+extern xfs_buf_t *xfs_buf_get_uncached(struct xfs_buftarg *, size_t, int);
+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);
+struct xfs_buf *xfs_buf_read_uncached(struct xfs_mount *mp,
+ struct xfs_buftarg *target,
+ xfs_daddr_t daddr, size_t length, int flags);
+
+/* 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_mount *mp, struct xfs_buf *bp);
+extern void xfs_bdwrite(void *mp, xfs_buf_t *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 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, 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 void xfs_buf_delwri_dequeue(xfs_buf_t *);
+extern void xfs_buf_delwri_promote(xfs_buf_t *);
+
+/* Buffer Daemon Setup Routines */
+extern int xfs_buf_init(void);
+extern void xfs_buf_terminate(void);
+
+static inline const char *
+xfs_buf_target_name(struct xfs_buftarg *target)
+{
+ static char __b[BDEVNAME_SIZE];
+
+ return bdevname(target->bt_bdev, __b);
+}
+
+
+#define XFS_BUF_ZEROFLAGS(bp) \
+ ((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC|XBF_DELWRI| \
+ XBF_SYNCIO|XBF_FUA|XBF_FLUSH))
+
+void xfs_buf_stale(struct xfs_buf *bp);
+#define XFS_BUF_STALE(bp) xfs_buf_stale(bp);
+#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
+#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_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_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_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_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))
+
+static inline void
+xfs_buf_set_ref(
+ struct xfs_buf *bp,
+ int lru_ref)
+{
+ atomic_set(&bp->b_lru_ref, lru_ref);
+}
+#define XFS_BUF_SET_VTYPE_REF(bp, type, ref) xfs_buf_set_ref(bp, ref)
+#define XFS_BUF_SET_VTYPE(bp, type) do { } while (0)
+
+static inline int xfs_buf_ispinned(struct xfs_buf *bp)
+{
+ return atomic_read(&bp->b_pin_count);
+}
+
+#define XFS_BUF_FINISH_IOWAIT(bp) complete(&bp->b_iowait);
+
+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);
+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__ */
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