Merge branches 'acpi_pad', 'acpica', 'apei-bugzilla-43282', 'battery', 'cpuidle-coupl...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / xfs / xfs_buf.h
CommitLineData
1da177e4 1/*
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NS
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
1da177e4 4 *
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5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
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LT
7 * published by the Free Software Foundation.
8 *
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9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
1da177e4 13 *
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14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4 17 */
1da177e4
LT
18#ifndef __XFS_BUF_H__
19#define __XFS_BUF_H__
20
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21#include <linux/list.h>
22#include <linux/types.h>
23#include <linux/spinlock.h>
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24#include <linux/mm.h>
25#include <linux/fs.h>
26#include <linux/buffer_head.h>
27#include <linux/uio.h>
28
29/*
30 * Base types
31 */
32
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33#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
34
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35typedef enum {
36 XBRW_READ = 1, /* transfer into target memory */
37 XBRW_WRITE = 2, /* transfer from target memory */
38 XBRW_ZERO = 3, /* Zero target memory */
39} xfs_buf_rw_t;
40
807cbbdb
CH
41#define XBF_READ (1 << 0) /* buffer intended for reading from device */
42#define XBF_WRITE (1 << 1) /* buffer intended for writing to device */
1d5ae5df 43#define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */
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CH
44#define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */
45#define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */
43ff2122 46#define XBF_STALE (1 << 6) /* buffer has been staled, do not find it */
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CH
47
48/* I/O hints for the BIO layer */
49#define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */
50#define XBF_FUA (1 << 11)/* force cache write through mode */
51#define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */
1da177e4 52
807cbbdb 53/* flags used only as arguments to access routines */
1d5ae5df 54#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
611c9946 55#define XBF_UNMAPPED (1 << 17)/* do not map the buffer */
1da177e4 56
807cbbdb 57/* flags used only internally */
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58#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
59#define _XBF_KMEM (1 << 21)/* backed by heap memory */
43ff2122 60#define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */
6ab455ee 61
807cbbdb 62typedef unsigned int xfs_buf_flags_t;
1da177e4 63
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64#define XFS_BUF_FLAGS \
65 { XBF_READ, "READ" }, \
66 { XBF_WRITE, "WRITE" }, \
1d5ae5df 67 { XBF_READ_AHEAD, "READ_AHEAD" }, \
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CH
68 { XBF_ASYNC, "ASYNC" }, \
69 { XBF_DONE, "DONE" }, \
0b1b213f 70 { XBF_STALE, "STALE" }, \
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CH
71 { XBF_SYNCIO, "SYNCIO" }, \
72 { XBF_FUA, "FUA" }, \
73 { XBF_FLUSH, "FLUSH" }, \
a8acad70 74 { XBF_TRYLOCK, "TRYLOCK" }, /* should never be set */\
611c9946 75 { XBF_UNMAPPED, "UNMAPPED" }, /* ditto */\
0b1b213f 76 { _XBF_PAGES, "PAGES" }, \
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DC
77 { _XBF_KMEM, "KMEM" }, \
78 { _XBF_DELWRI_Q, "DELWRI_Q" }
0b1b213f 79
1da177e4 80typedef struct xfs_buftarg {
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81 dev_t bt_dev;
82 struct block_device *bt_bdev;
0e6e847f 83 struct backing_dev_info *bt_bdi;
ebad861b 84 struct xfs_mount *bt_mount;
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85 unsigned int bt_bsize;
86 unsigned int bt_sshift;
87 size_t bt_smask;
88
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DC
89 /* LRU control structures */
90 struct shrinker bt_shrinker;
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DC
91 struct list_head bt_lru;
92 spinlock_t bt_lru_lock;
93 unsigned int bt_lru_nr;
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94} xfs_buftarg_t;
95
1da177e4 96struct xfs_buf;
ce8e922c 97typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);
1da177e4 98
ce8e922c 99#define XB_PAGES 2
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100
101typedef struct xfs_buf {
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DC
102 /*
103 * first cacheline holds all the fields needed for an uncontended cache
104 * hit to be fully processed. The semaphore straddles the cacheline
105 * boundary, but the counter and lock sits on the first cacheline,
106 * which is the only bit that is touched if we hit the semaphore
107 * fast-path on locking.
108 */
109 struct rb_node b_rbnode; /* rbtree node */
de1cbee4 110 xfs_daddr_t b_bn; /* block number for I/O */
4e94b71b 111 int b_length; /* size of buffer in BBs */
50f59e8e 112 atomic_t b_hold; /* reference count */
430cbeb8 113 atomic_t b_lru_ref; /* lru reclaim ref count */
50f59e8e 114 xfs_buf_flags_t b_flags; /* status flags */
ce8e922c 115 struct semaphore b_sema; /* semaphore for lockables */
50f59e8e 116
430cbeb8 117 struct list_head b_lru; /* lru list */
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118 wait_queue_head_t b_waiters; /* unpin waiters */
119 struct list_head b_list;
74f75a0c 120 struct xfs_perag *b_pag; /* contains rbtree root */
ce8e922c 121 xfs_buftarg_t *b_target; /* buffer target (device) */
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122 void *b_addr; /* virtual address of buffer */
123 struct work_struct b_iodone_work;
ce8e922c 124 xfs_buf_iodone_t b_iodone; /* I/O completion function */
b4dd330b 125 struct completion b_iowait; /* queue for I/O waiters */
ce8e922c 126 void *b_fspriv;
bf9d9013 127 struct xfs_trans *b_transp;
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128 struct page **b_pages; /* array of page pointers */
129 struct page *b_page_array[XB_PAGES]; /* inline pages */
aa0e8833 130 int b_io_length; /* IO size in BBs */
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131 atomic_t b_pin_count; /* pin count */
132 atomic_t b_io_remaining; /* #outstanding I/O requests */
133 unsigned int b_page_count; /* size of page array */
134 unsigned int b_offset; /* page offset in first page */
135 unsigned short b_error; /* error code on I/O */
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136#ifdef XFS_BUF_LOCK_TRACKING
137 int b_last_holder;
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138#endif
139} xfs_buf_t;
140
141
142/* Finding and Reading Buffers */
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143struct xfs_buf *_xfs_buf_find(struct xfs_buftarg *target, xfs_daddr_t blkno,
144 size_t numblks, xfs_buf_flags_t flags,
145 struct xfs_buf *new_bp);
1da177e4 146#define xfs_incore(buftarg,blkno,len,lockit) \
ce8e922c 147 _xfs_buf_find(buftarg, blkno ,len, lockit, NULL)
1da177e4 148
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149struct xfs_buf *xfs_buf_get(struct xfs_buftarg *target, xfs_daddr_t blkno,
150 size_t numblks, xfs_buf_flags_t flags);
151struct xfs_buf *xfs_buf_read(struct xfs_buftarg *target, xfs_daddr_t blkno,
152 size_t numblks, xfs_buf_flags_t flags);
153void xfs_buf_readahead(struct xfs_buftarg *target, xfs_daddr_t blkno,
154 size_t numblks);
155
156struct xfs_buf *xfs_buf_get_empty(struct xfs_buftarg *target, size_t numblks);
157struct xfs_buf *xfs_buf_alloc(struct xfs_buftarg *target, xfs_daddr_t blkno,
158 size_t numblks, xfs_buf_flags_t flags);
159void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks);
160int xfs_buf_associate_memory(struct xfs_buf *bp, void *mem, size_t length);
161
162struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks,
163 int flags);
164struct xfs_buf *xfs_buf_read_uncached(struct xfs_buftarg *target,
165 xfs_daddr_t daddr, size_t numblks, int flags);
166void xfs_buf_hold(struct xfs_buf *bp);
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167
168/* Releasing Buffers */
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169extern void xfs_buf_free(xfs_buf_t *);
170extern void xfs_buf_rele(xfs_buf_t *);
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171
172/* Locking and Unlocking Buffers */
0c842ad4 173extern int xfs_buf_trylock(xfs_buf_t *);
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174extern void xfs_buf_lock(xfs_buf_t *);
175extern void xfs_buf_unlock(xfs_buf_t *);
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176#define xfs_buf_islocked(bp) \
177 ((bp)->b_sema.count <= 0)
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178
179/* Buffer Read and Write Routines */
c2b006c1 180extern int xfs_bwrite(struct xfs_buf *bp);
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181
182extern void xfsbdstrat(struct xfs_mount *, struct xfs_buf *);
4e23471a 183
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184extern void xfs_buf_ioend(xfs_buf_t *, int);
185extern void xfs_buf_ioerror(xfs_buf_t *, int);
901796af 186extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func);
0e95f19a 187extern void xfs_buf_iorequest(xfs_buf_t *);
ce8e922c 188extern int xfs_buf_iowait(xfs_buf_t *);
b9c48649 189extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *,
ce8e922c 190 xfs_buf_rw_t);
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CH
191#define xfs_buf_zero(bp, off, len) \
192 xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
ce8e922c 193
ce8e922c 194static inline int xfs_buf_geterror(xfs_buf_t *bp)
1da177e4 195{
ce8e922c 196 return bp ? bp->b_error : ENOMEM;
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197}
198
199/* Buffer Utility Routines */
ce8e922c 200extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);
1da177e4 201
1da177e4 202/* Delayed Write Buffer Routines */
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CH
203extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
204extern int xfs_buf_delwri_submit(struct list_head *);
205extern int xfs_buf_delwri_submit_nowait(struct list_head *);
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206
207/* Buffer Daemon Setup Routines */
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208extern int xfs_buf_init(void);
209extern void xfs_buf_terminate(void);
1da177e4 210
1d5ae5df 211#define XFS_BUF_ZEROFLAGS(bp) \
43ff2122 212 ((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC| \
1d5ae5df 213 XBF_SYNCIO|XBF_FUA|XBF_FLUSH))
ce8e922c 214
430cbeb8 215void xfs_buf_stale(struct xfs_buf *bp);
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CH
216#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
217#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE)
1da177e4 218
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219#define XFS_BUF_DONE(bp) ((bp)->b_flags |= XBF_DONE)
220#define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE)
221#define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE)
222
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223#define XFS_BUF_ASYNC(bp) ((bp)->b_flags |= XBF_ASYNC)
224#define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC)
225#define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC)
226
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227#define XFS_BUF_READ(bp) ((bp)->b_flags |= XBF_READ)
228#define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ)
229#define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ)
230
231#define XFS_BUF_WRITE(bp) ((bp)->b_flags |= XBF_WRITE)
232#define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE)
233#define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE)
234
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235#define XFS_BUF_ADDR(bp) ((bp)->b_bn)
236#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_bn = (xfs_daddr_t)(bno))
ce8e922c 237
38f23232 238static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref)
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DC
239{
240 atomic_set(&bp->b_lru_ref, lru_ref);
241}
ce8e922c 242
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243static inline int xfs_buf_ispinned(struct xfs_buf *bp)
244{
245 return atomic_read(&bp->b_pin_count);
246}
ce8e922c 247
ce8e922c 248static inline void xfs_buf_relse(xfs_buf_t *bp)
1da177e4 249{
bfc60177 250 xfs_buf_unlock(bp);
ce8e922c 251 xfs_buf_rele(bp);
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252}
253
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LT
254/*
255 * Handling of buftargs.
256 */
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DC
257extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
258 struct block_device *, int, const char *);
c141b292 259extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
1da177e4
LT
260extern void xfs_wait_buftarg(xfs_buftarg_t *);
261extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
d808f617 262
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NS
263#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
264#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
265
1da177e4 266#endif /* __XFS_BUF_H__ */