Commit | Line | Data |
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1da177e4 | 1 | /* |
7b718769 NS |
2 | * Copyright (c) 2000-2005 Silicon Graphics, Inc. |
3 | * All Rights Reserved. | |
1da177e4 | 4 | * |
7b718769 NS |
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 | |
1da177e4 LT |
7 | * published by the Free Software Foundation. |
8 | * | |
7b718769 NS |
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 | * |
7b718769 NS |
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 | ||
1da177e4 LT |
21 | #include <linux/list.h> |
22 | #include <linux/types.h> | |
23 | #include <linux/spinlock.h> | |
1da177e4 LT |
24 | #include <linux/mm.h> |
25 | #include <linux/fs.h> | |
26 | #include <linux/buffer_head.h> | |
27 | #include <linux/uio.h> | |
e80dfa19 | 28 | #include <linux/list_lru.h> |
1da177e4 LT |
29 | |
30 | /* | |
31 | * Base types | |
32 | */ | |
33 | ||
ce8e922c NS |
34 | #define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL)) |
35 | ||
ce8e922c NS |
36 | typedef enum { |
37 | XBRW_READ = 1, /* transfer into target memory */ | |
38 | XBRW_WRITE = 2, /* transfer from target memory */ | |
39 | XBRW_ZERO = 3, /* Zero target memory */ | |
40 | } xfs_buf_rw_t; | |
41 | ||
6fb8a90a CM |
42 | #define XBF_READ (1 << 0) /* buffer intended for reading from device */ |
43 | #define XBF_WRITE (1 << 1) /* buffer intended for writing to device */ | |
44 | #define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */ | |
45 | #define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */ | |
46 | #define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */ | |
47 | #define XBF_STALE (1 << 6) /* buffer has been staled, do not find it */ | |
1d5ae5df CH |
48 | |
49 | /* I/O hints for the BIO layer */ | |
6fb8a90a CM |
50 | #define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */ |
51 | #define XBF_FUA (1 << 11)/* force cache write through mode */ | |
52 | #define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */ | |
1da177e4 | 53 | |
807cbbdb | 54 | /* flags used only as arguments to access routines */ |
6fb8a90a CM |
55 | #define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */ |
56 | #define XBF_UNMAPPED (1 << 17)/* do not map the buffer */ | |
1da177e4 | 57 | |
807cbbdb | 58 | /* flags used only internally */ |
6fb8a90a CM |
59 | #define _XBF_PAGES (1 << 20)/* backed by refcounted pages */ |
60 | #define _XBF_KMEM (1 << 21)/* backed by heap memory */ | |
61 | #define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */ | |
62 | #define _XBF_COMPOUND (1 << 23)/* compound buffer */ | |
6ab455ee | 63 | |
807cbbdb | 64 | typedef unsigned int xfs_buf_flags_t; |
1da177e4 | 65 | |
0b1b213f CH |
66 | #define XFS_BUF_FLAGS \ |
67 | { XBF_READ, "READ" }, \ | |
68 | { XBF_WRITE, "WRITE" }, \ | |
1d5ae5df | 69 | { XBF_READ_AHEAD, "READ_AHEAD" }, \ |
0b1b213f CH |
70 | { XBF_ASYNC, "ASYNC" }, \ |
71 | { XBF_DONE, "DONE" }, \ | |
0b1b213f | 72 | { XBF_STALE, "STALE" }, \ |
1d5ae5df CH |
73 | { XBF_SYNCIO, "SYNCIO" }, \ |
74 | { XBF_FUA, "FUA" }, \ | |
75 | { XBF_FLUSH, "FLUSH" }, \ | |
6fb8a90a | 76 | { XBF_TRYLOCK, "TRYLOCK" }, /* should never be set */\ |
611c9946 | 77 | { XBF_UNMAPPED, "UNMAPPED" }, /* ditto */\ |
0b1b213f | 78 | { _XBF_PAGES, "PAGES" }, \ |
0e6e847f | 79 | { _XBF_KMEM, "KMEM" }, \ |
cbb7baab | 80 | { _XBF_DELWRI_Q, "DELWRI_Q" }, \ |
a4082357 DC |
81 | { _XBF_COMPOUND, "COMPOUND" } |
82 | ||
83 | /* | |
84 | * Internal state flags. | |
85 | */ | |
86 | #define XFS_BSTATE_DISPOSE (1 << 0) /* buffer being discarded */ | |
0b1b213f | 87 | |
1da177e4 | 88 | typedef struct xfs_buftarg { |
ce8e922c NS |
89 | dev_t bt_dev; |
90 | struct block_device *bt_bdev; | |
0e6e847f | 91 | struct backing_dev_info *bt_bdi; |
ebad861b | 92 | struct xfs_mount *bt_mount; |
ce8e922c NS |
93 | unsigned int bt_bsize; |
94 | unsigned int bt_sshift; | |
95 | size_t bt_smask; | |
96 | ||
ff57ab21 DC |
97 | /* LRU control structures */ |
98 | struct shrinker bt_shrinker; | |
e80dfa19 | 99 | struct list_lru bt_lru; |
1da177e4 LT |
100 | } xfs_buftarg_t; |
101 | ||
1da177e4 | 102 | struct xfs_buf; |
ce8e922c | 103 | typedef void (*xfs_buf_iodone_t)(struct xfs_buf *); |
1da177e4 | 104 | |
c3f8fc73 | 105 | |
ce8e922c | 106 | #define XB_PAGES 2 |
1da177e4 | 107 | |
cbb7baab DC |
108 | struct xfs_buf_map { |
109 | xfs_daddr_t bm_bn; /* block number for I/O */ | |
110 | int bm_len; /* size of I/O */ | |
111 | }; | |
112 | ||
3e85c868 DC |
113 | #define DEFINE_SINGLE_BUF_MAP(map, blkno, numblk) \ |
114 | struct xfs_buf_map (map) = { .bm_bn = (blkno), .bm_len = (numblk) }; | |
115 | ||
1813dd64 DC |
116 | struct xfs_buf_ops { |
117 | void (*verify_read)(struct xfs_buf *); | |
118 | void (*verify_write)(struct xfs_buf *); | |
119 | }; | |
120 | ||
1da177e4 | 121 | typedef struct xfs_buf { |
50f59e8e DC |
122 | /* |
123 | * first cacheline holds all the fields needed for an uncontended cache | |
124 | * hit to be fully processed. The semaphore straddles the cacheline | |
125 | * boundary, but the counter and lock sits on the first cacheline, | |
126 | * which is the only bit that is touched if we hit the semaphore | |
127 | * fast-path on locking. | |
128 | */ | |
129 | struct rb_node b_rbnode; /* rbtree node */ | |
cbb7baab | 130 | xfs_daddr_t b_bn; /* block number of buffer */ |
4e94b71b | 131 | int b_length; /* size of buffer in BBs */ |
50f59e8e | 132 | atomic_t b_hold; /* reference count */ |
430cbeb8 | 133 | atomic_t b_lru_ref; /* lru reclaim ref count */ |
50f59e8e | 134 | xfs_buf_flags_t b_flags; /* status flags */ |
ce8e922c | 135 | struct semaphore b_sema; /* semaphore for lockables */ |
50f59e8e | 136 | |
6fb8a90a CM |
137 | /* |
138 | * concurrent access to b_lru and b_lru_flags are protected by | |
139 | * bt_lru_lock and not by b_sema | |
140 | */ | |
430cbeb8 | 141 | struct list_head b_lru; /* lru list */ |
a4082357 DC |
142 | spinlock_t b_lock; /* internal state lock */ |
143 | unsigned int b_state; /* internal state flags */ | |
ce8e922c NS |
144 | wait_queue_head_t b_waiters; /* unpin waiters */ |
145 | struct list_head b_list; | |
74f75a0c | 146 | struct xfs_perag *b_pag; /* contains rbtree root */ |
ce8e922c | 147 | xfs_buftarg_t *b_target; /* buffer target (device) */ |
ce8e922c NS |
148 | void *b_addr; /* virtual address of buffer */ |
149 | struct work_struct b_iodone_work; | |
ce8e922c | 150 | xfs_buf_iodone_t b_iodone; /* I/O completion function */ |
b4dd330b | 151 | struct completion b_iowait; /* queue for I/O waiters */ |
ce8e922c | 152 | void *b_fspriv; |
bf9d9013 | 153 | struct xfs_trans *b_transp; |
ce8e922c NS |
154 | struct page **b_pages; /* array of page pointers */ |
155 | struct page *b_page_array[XB_PAGES]; /* inline pages */ | |
3e85c868 | 156 | struct xfs_buf_map *b_maps; /* compound buffer map */ |
d44d9bc6 | 157 | struct xfs_buf_map __b_map; /* inline compound buffer map */ |
3e85c868 | 158 | int b_map_count; |
aa0e8833 | 159 | int b_io_length; /* IO size in BBs */ |
50f59e8e DC |
160 | atomic_t b_pin_count; /* pin count */ |
161 | atomic_t b_io_remaining; /* #outstanding I/O requests */ | |
162 | unsigned int b_page_count; /* size of page array */ | |
163 | unsigned int b_offset; /* page offset in first page */ | |
164 | unsigned short b_error; /* error code on I/O */ | |
1813dd64 | 165 | const struct xfs_buf_ops *b_ops; |
cfb02852 | 166 | |
ce8e922c NS |
167 | #ifdef XFS_BUF_LOCK_TRACKING |
168 | int b_last_holder; | |
1da177e4 LT |
169 | #endif |
170 | } xfs_buf_t; | |
171 | ||
1da177e4 | 172 | /* Finding and Reading Buffers */ |
3e85c868 DC |
173 | struct xfs_buf *_xfs_buf_find(struct xfs_buftarg *target, |
174 | struct xfs_buf_map *map, int nmaps, | |
175 | xfs_buf_flags_t flags, struct xfs_buf *new_bp); | |
176 | ||
177 | static inline struct xfs_buf * | |
178 | xfs_incore( | |
179 | struct xfs_buftarg *target, | |
180 | xfs_daddr_t blkno, | |
181 | size_t numblks, | |
182 | xfs_buf_flags_t flags) | |
183 | { | |
184 | DEFINE_SINGLE_BUF_MAP(map, blkno, numblks); | |
185 | return _xfs_buf_find(target, &map, 1, flags, NULL); | |
186 | } | |
187 | ||
188 | struct xfs_buf *_xfs_buf_alloc(struct xfs_buftarg *target, | |
189 | struct xfs_buf_map *map, int nmaps, | |
190 | xfs_buf_flags_t flags); | |
191 | ||
192 | static inline struct xfs_buf * | |
193 | xfs_buf_alloc( | |
194 | struct xfs_buftarg *target, | |
195 | xfs_daddr_t blkno, | |
196 | size_t numblks, | |
197 | xfs_buf_flags_t flags) | |
198 | { | |
199 | DEFINE_SINGLE_BUF_MAP(map, blkno, numblks); | |
200 | return _xfs_buf_alloc(target, &map, 1, flags); | |
201 | } | |
1da177e4 | 202 | |
6dde2707 DC |
203 | struct xfs_buf *xfs_buf_get_map(struct xfs_buftarg *target, |
204 | struct xfs_buf_map *map, int nmaps, | |
205 | xfs_buf_flags_t flags); | |
206 | struct xfs_buf *xfs_buf_read_map(struct xfs_buftarg *target, | |
207 | struct xfs_buf_map *map, int nmaps, | |
1813dd64 DC |
208 | xfs_buf_flags_t flags, |
209 | const struct xfs_buf_ops *ops); | |
6dde2707 | 210 | void xfs_buf_readahead_map(struct xfs_buftarg *target, |
c3f8fc73 | 211 | struct xfs_buf_map *map, int nmaps, |
1813dd64 | 212 | const struct xfs_buf_ops *ops); |
6dde2707 DC |
213 | |
214 | static inline struct xfs_buf * | |
215 | xfs_buf_get( | |
216 | struct xfs_buftarg *target, | |
217 | xfs_daddr_t blkno, | |
218 | size_t numblks, | |
219 | xfs_buf_flags_t flags) | |
220 | { | |
221 | DEFINE_SINGLE_BUF_MAP(map, blkno, numblks); | |
222 | return xfs_buf_get_map(target, &map, 1, flags); | |
223 | } | |
224 | ||
225 | static inline struct xfs_buf * | |
226 | xfs_buf_read( | |
227 | struct xfs_buftarg *target, | |
228 | xfs_daddr_t blkno, | |
229 | size_t numblks, | |
c3f8fc73 | 230 | xfs_buf_flags_t flags, |
1813dd64 | 231 | const struct xfs_buf_ops *ops) |
6dde2707 DC |
232 | { |
233 | DEFINE_SINGLE_BUF_MAP(map, blkno, numblks); | |
1813dd64 | 234 | return xfs_buf_read_map(target, &map, 1, flags, ops); |
6dde2707 DC |
235 | } |
236 | ||
237 | static inline void | |
238 | xfs_buf_readahead( | |
239 | struct xfs_buftarg *target, | |
240 | xfs_daddr_t blkno, | |
c3f8fc73 | 241 | size_t numblks, |
1813dd64 | 242 | const struct xfs_buf_ops *ops) |
6dde2707 DC |
243 | { |
244 | DEFINE_SINGLE_BUF_MAP(map, blkno, numblks); | |
1813dd64 | 245 | return xfs_buf_readahead_map(target, &map, 1, ops); |
6dde2707 | 246 | } |
e70b73f8 DC |
247 | |
248 | struct xfs_buf *xfs_buf_get_empty(struct xfs_buftarg *target, size_t numblks); | |
e70b73f8 DC |
249 | void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks); |
250 | int xfs_buf_associate_memory(struct xfs_buf *bp, void *mem, size_t length); | |
251 | ||
252 | struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks, | |
253 | int flags); | |
254 | struct xfs_buf *xfs_buf_read_uncached(struct xfs_buftarg *target, | |
c3f8fc73 | 255 | xfs_daddr_t daddr, size_t numblks, int flags, |
1813dd64 | 256 | const struct xfs_buf_ops *ops); |
e70b73f8 | 257 | void xfs_buf_hold(struct xfs_buf *bp); |
1da177e4 LT |
258 | |
259 | /* Releasing Buffers */ | |
ce8e922c NS |
260 | extern void xfs_buf_free(xfs_buf_t *); |
261 | extern void xfs_buf_rele(xfs_buf_t *); | |
1da177e4 LT |
262 | |
263 | /* Locking and Unlocking Buffers */ | |
0c842ad4 | 264 | extern int xfs_buf_trylock(xfs_buf_t *); |
ce8e922c NS |
265 | extern void xfs_buf_lock(xfs_buf_t *); |
266 | extern void xfs_buf_unlock(xfs_buf_t *); | |
0c842ad4 CH |
267 | #define xfs_buf_islocked(bp) \ |
268 | ((bp)->b_sema.count <= 0) | |
1da177e4 LT |
269 | |
270 | /* Buffer Read and Write Routines */ | |
c2b006c1 | 271 | extern int xfs_bwrite(struct xfs_buf *bp); |
4e23471a CH |
272 | |
273 | extern void xfsbdstrat(struct xfs_mount *, struct xfs_buf *); | |
4e23471a | 274 | |
ce8e922c NS |
275 | extern void xfs_buf_ioend(xfs_buf_t *, int); |
276 | extern void xfs_buf_ioerror(xfs_buf_t *, int); | |
901796af | 277 | extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func); |
0e95f19a | 278 | extern void xfs_buf_iorequest(xfs_buf_t *); |
ce8e922c | 279 | extern int xfs_buf_iowait(xfs_buf_t *); |
b9c48649 | 280 | extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *, |
ce8e922c | 281 | xfs_buf_rw_t); |
1a1a3e97 CH |
282 | #define xfs_buf_zero(bp, off, len) \ |
283 | xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO) | |
ce8e922c | 284 | |
ce8e922c | 285 | static inline int xfs_buf_geterror(xfs_buf_t *bp) |
1da177e4 | 286 | { |
ce8e922c | 287 | return bp ? bp->b_error : ENOMEM; |
1da177e4 LT |
288 | } |
289 | ||
290 | /* Buffer Utility Routines */ | |
ce8e922c | 291 | extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t); |
1da177e4 | 292 | |
1da177e4 | 293 | /* Delayed Write Buffer Routines */ |
43ff2122 CH |
294 | extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *); |
295 | extern int xfs_buf_delwri_submit(struct list_head *); | |
296 | extern int xfs_buf_delwri_submit_nowait(struct list_head *); | |
1da177e4 LT |
297 | |
298 | /* Buffer Daemon Setup Routines */ | |
ce8e922c NS |
299 | extern int xfs_buf_init(void); |
300 | extern void xfs_buf_terminate(void); | |
1da177e4 | 301 | |
1d5ae5df | 302 | #define XFS_BUF_ZEROFLAGS(bp) \ |
43ff2122 | 303 | ((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC| \ |
1d5ae5df | 304 | XBF_SYNCIO|XBF_FUA|XBF_FLUSH)) |
ce8e922c | 305 | |
430cbeb8 | 306 | void xfs_buf_stale(struct xfs_buf *bp); |
0cadda1c CH |
307 | #define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE) |
308 | #define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE) | |
1da177e4 | 309 | |
ce8e922c NS |
310 | #define XFS_BUF_DONE(bp) ((bp)->b_flags |= XBF_DONE) |
311 | #define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE) | |
312 | #define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE) | |
313 | ||
ce8e922c NS |
314 | #define XFS_BUF_ASYNC(bp) ((bp)->b_flags |= XBF_ASYNC) |
315 | #define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC) | |
316 | #define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC) | |
317 | ||
ce8e922c NS |
318 | #define XFS_BUF_READ(bp) ((bp)->b_flags |= XBF_READ) |
319 | #define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ) | |
320 | #define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ) | |
321 | ||
322 | #define XFS_BUF_WRITE(bp) ((bp)->b_flags |= XBF_WRITE) | |
323 | #define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE) | |
324 | #define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE) | |
325 | ||
cbb7baab DC |
326 | /* |
327 | * These macros use the IO block map rather than b_bn. b_bn is now really | |
328 | * just for the buffer cache index for cached buffers. As IO does not use b_bn | |
329 | * anymore, uncached buffers do not use b_bn at all and hence must modify the IO | |
330 | * map directly. Uncached buffers are not allowed to be discontiguous, so this | |
331 | * is safe to do. | |
332 | * | |
333 | * In future, uncached buffers will pass the block number directly to the io | |
334 | * request function and hence these macros will go away at that point. | |
335 | */ | |
d44d9bc6 MT |
336 | #define XFS_BUF_ADDR(bp) ((bp)->b_maps[0].bm_bn) |
337 | #define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_maps[0].bm_bn = (xfs_daddr_t)(bno)) | |
ce8e922c | 338 | |
38f23232 | 339 | static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref) |
821eb21d DC |
340 | { |
341 | atomic_set(&bp->b_lru_ref, lru_ref); | |
342 | } | |
ce8e922c | 343 | |
811e64c7 CS |
344 | static inline int xfs_buf_ispinned(struct xfs_buf *bp) |
345 | { | |
346 | return atomic_read(&bp->b_pin_count); | |
347 | } | |
ce8e922c | 348 | |
ce8e922c | 349 | static inline void xfs_buf_relse(xfs_buf_t *bp) |
1da177e4 | 350 | { |
bfc60177 | 351 | xfs_buf_unlock(bp); |
ce8e922c | 352 | xfs_buf_rele(bp); |
1da177e4 LT |
353 | } |
354 | ||
1da177e4 LT |
355 | /* |
356 | * Handling of buftargs. | |
357 | */ | |
ebad861b DC |
358 | extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *, |
359 | struct block_device *, int, const char *); | |
c141b292 | 360 | extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *); |
1da177e4 LT |
361 | extern void xfs_wait_buftarg(xfs_buftarg_t *); |
362 | extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int); | |
d808f617 | 363 | |
ce8e922c NS |
364 | #define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev) |
365 | #define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev) | |
366 | ||
1da177e4 | 367 | #endif /* __XFS_BUF_H__ */ |