Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#ifndef __XFS_BUF_H__
7#define __XFS_BUF_H__
8
9#include <linux/list.h>
10#include <linux/types.h>
11#include <linux/spinlock.h>
12#include <linux/mm.h>
13#include <linux/fs.h>
14#include <linux/dax.h>
15#include <linux/uio.h>
16#include <linux/list_lru.h>
17
18/*
19 * Base types
20 */
21struct xfs_buf;
22
23#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
24
25#define XBF_READ (1 << 0) /* buffer intended for reading from device */
26#define XBF_WRITE (1 << 1) /* buffer intended for writing to device */
27#define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */
28#define XBF_NO_IOACCT (1 << 3) /* bypass I/O accounting (non-LRU bufs) */
29#define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */
30#define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */
31#define XBF_STALE (1 << 6) /* buffer has been staled, do not find it */
32#define XBF_WRITE_FAIL (1 << 7) /* async writes have failed on this buffer */
33
34/* buffer type flags for write callbacks */
35#define _XBF_INODES (1 << 16)/* inode buffer */
36#define _XBF_DQUOTS (1 << 17)/* dquot buffer */
37#define _XBF_LOGRECOVERY (1 << 18)/* log recovery buffer */
38
39/* flags used only internally */
40#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
41#define _XBF_KMEM (1 << 21)/* backed by heap memory */
42#define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */
43
44/* flags used only as arguments to access routines */
45#define XBF_TRYLOCK (1 << 30)/* lock requested, but do not wait */
46#define XBF_UNMAPPED (1 << 31)/* do not map the buffer */
47
48typedef unsigned int xfs_buf_flags_t;
49
50#define XFS_BUF_FLAGS \
51 { XBF_READ, "READ" }, \
52 { XBF_WRITE, "WRITE" }, \
53 { XBF_READ_AHEAD, "READ_AHEAD" }, \
54 { XBF_NO_IOACCT, "NO_IOACCT" }, \
55 { XBF_ASYNC, "ASYNC" }, \
56 { XBF_DONE, "DONE" }, \
57 { XBF_STALE, "STALE" }, \
58 { XBF_WRITE_FAIL, "WRITE_FAIL" }, \
59 { _XBF_INODES, "INODES" }, \
60 { _XBF_DQUOTS, "DQUOTS" }, \
61 { _XBF_LOGRECOVERY, "LOG_RECOVERY" }, \
62 { _XBF_PAGES, "PAGES" }, \
63 { _XBF_KMEM, "KMEM" }, \
64 { _XBF_DELWRI_Q, "DELWRI_Q" }, \
65 /* The following interface flags should never be set */ \
66 { XBF_TRYLOCK, "TRYLOCK" }, \
67 { XBF_UNMAPPED, "UNMAPPED" }
68
69/*
70 * Internal state flags.
71 */
72#define XFS_BSTATE_DISPOSE (1 << 0) /* buffer being discarded */
73#define XFS_BSTATE_IN_FLIGHT (1 << 1) /* I/O in flight */
74
75/*
76 * The xfs_buftarg contains 2 notions of "sector size" -
77 *
78 * 1) The metadata sector size, which is the minimum unit and
79 * alignment of IO which will be performed by metadata operations.
80 * 2) The device logical sector size
81 *
82 * The first is specified at mkfs time, and is stored on-disk in the
83 * superblock's sb_sectsize.
84 *
85 * The latter is derived from the underlying device, and controls direct IO
86 * alignment constraints.
87 */
88typedef struct xfs_buftarg {
89 dev_t bt_dev;
90 struct block_device *bt_bdev;
91 struct dax_device *bt_daxdev;
92 struct xfs_mount *bt_mount;
93 unsigned int bt_meta_sectorsize;
94 size_t bt_meta_sectormask;
95 size_t bt_logical_sectorsize;
96 size_t bt_logical_sectormask;
97
98 /* LRU control structures */
99 struct shrinker bt_shrinker;
100 struct list_lru bt_lru;
101
102 struct percpu_counter bt_io_count;
103 struct ratelimit_state bt_ioerror_rl;
104} xfs_buftarg_t;
105
106#define XB_PAGES 2
107
108struct xfs_buf_map {
109 xfs_daddr_t bm_bn; /* block number for I/O */
110 int bm_len; /* size of I/O */
111};
112
113#define DEFINE_SINGLE_BUF_MAP(map, blkno, numblk) \
114 struct xfs_buf_map (map) = { .bm_bn = (blkno), .bm_len = (numblk) };
115
116struct xfs_buf_ops {
117 char *name;
118 union {
119 __be32 magic[2]; /* v4 and v5 on disk magic values */
120 __be16 magic16[2]; /* v4 and v5 on disk magic values */
121 };
122 void (*verify_read)(struct xfs_buf *);
123 void (*verify_write)(struct xfs_buf *);
124 xfs_failaddr_t (*verify_struct)(struct xfs_buf *bp);
125};
126
127struct xfs_buf {
128 /*
129 * first cacheline holds all the fields needed for an uncontended cache
130 * hit to be fully processed. The semaphore straddles the cacheline
131 * boundary, but the counter and lock sits on the first cacheline,
132 * which is the only bit that is touched if we hit the semaphore
133 * fast-path on locking.
134 */
135 struct rhash_head b_rhash_head; /* pag buffer hash node */
136 xfs_daddr_t b_bn; /* block number of buffer */
137 int b_length; /* size of buffer in BBs */
138 atomic_t b_hold; /* reference count */
139 atomic_t b_lru_ref; /* lru reclaim ref count */
140 xfs_buf_flags_t b_flags; /* status flags */
141 struct semaphore b_sema; /* semaphore for lockables */
142
143 /*
144 * concurrent access to b_lru and b_lru_flags are protected by
145 * bt_lru_lock and not by b_sema
146 */
147 struct list_head b_lru; /* lru list */
148 spinlock_t b_lock; /* internal state lock */
149 unsigned int b_state; /* internal state flags */
150 int b_io_error; /* internal IO error state */
151 wait_queue_head_t b_waiters; /* unpin waiters */
152 struct list_head b_list;
153 struct xfs_perag *b_pag; /* contains rbtree root */
154 struct xfs_mount *b_mount;
155 struct xfs_buftarg *b_target; /* buffer target (device) */
156 void *b_addr; /* virtual address of buffer */
157 struct work_struct b_ioend_work;
158 struct completion b_iowait; /* queue for I/O waiters */
159 struct xfs_buf_log_item *b_log_item;
160 struct list_head b_li_list; /* Log items list head */
161 struct xfs_trans *b_transp;
162 struct page **b_pages; /* array of page pointers */
163 struct page *b_page_array[XB_PAGES]; /* inline pages */
164 struct xfs_buf_map *b_maps; /* compound buffer map */
165 struct xfs_buf_map __b_map; /* inline compound buffer map */
166 int b_map_count;
167 atomic_t b_pin_count; /* pin count */
168 atomic_t b_io_remaining; /* #outstanding I/O requests */
169 unsigned int b_page_count; /* size of page array */
170 unsigned int b_offset; /* page offset of b_addr,
171 only for _XBF_KMEM buffers */
172 int b_error; /* error code on I/O */
173
174 /*
175 * async write failure retry count. Initialised to zero on the first
176 * failure, then when it exceeds the maximum configured without a
177 * success the write is considered to be failed permanently and the
178 * iodone handler will take appropriate action.
179 *
180 * For retry timeouts, we record the jiffie of the first failure. This
181 * means that we can change the retry timeout for buffers already under
182 * I/O and thus avoid getting stuck in a retry loop with a long timeout.
183 *
184 * last_error is used to ensure that we are getting repeated errors, not
185 * different errors. e.g. a block device might change ENOSPC to EIO when
186 * a failure timeout occurs, so we want to re-initialise the error
187 * retry behaviour appropriately when that happens.
188 */
189 int b_retries;
190 unsigned long b_first_retry_time; /* in jiffies */
191 int b_last_error;
192
193 const struct xfs_buf_ops *b_ops;
194};
195
196/* Finding and Reading Buffers */
197struct xfs_buf *xfs_buf_incore(struct xfs_buftarg *target,
198 xfs_daddr_t blkno, size_t numblks,
199 xfs_buf_flags_t flags);
200
201int xfs_buf_get_map(struct xfs_buftarg *target, struct xfs_buf_map *map,
202 int nmaps, xfs_buf_flags_t flags, struct xfs_buf **bpp);
203int xfs_buf_read_map(struct xfs_buftarg *target, struct xfs_buf_map *map,
204 int nmaps, xfs_buf_flags_t flags, struct xfs_buf **bpp,
205 const struct xfs_buf_ops *ops, xfs_failaddr_t fa);
206void xfs_buf_readahead_map(struct xfs_buftarg *target,
207 struct xfs_buf_map *map, int nmaps,
208 const struct xfs_buf_ops *ops);
209
210static inline int
211xfs_buf_get(
212 struct xfs_buftarg *target,
213 xfs_daddr_t blkno,
214 size_t numblks,
215 struct xfs_buf **bpp)
216{
217 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
218
219 return xfs_buf_get_map(target, &map, 1, 0, bpp);
220}
221
222static inline int
223xfs_buf_read(
224 struct xfs_buftarg *target,
225 xfs_daddr_t blkno,
226 size_t numblks,
227 xfs_buf_flags_t flags,
228 struct xfs_buf **bpp,
229 const struct xfs_buf_ops *ops)
230{
231 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
232
233 return xfs_buf_read_map(target, &map, 1, flags, bpp, ops,
234 __builtin_return_address(0));
235}
236
237static inline void
238xfs_buf_readahead(
239 struct xfs_buftarg *target,
240 xfs_daddr_t blkno,
241 size_t numblks,
242 const struct xfs_buf_ops *ops)
243{
244 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
245 return xfs_buf_readahead_map(target, &map, 1, ops);
246}
247
248int xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks, int flags,
249 struct xfs_buf **bpp);
250int xfs_buf_read_uncached(struct xfs_buftarg *target, xfs_daddr_t daddr,
251 size_t numblks, int flags, struct xfs_buf **bpp,
252 const struct xfs_buf_ops *ops);
253int _xfs_buf_read(struct xfs_buf *bp, xfs_buf_flags_t flags);
254void xfs_buf_hold(struct xfs_buf *bp);
255
256/* Releasing Buffers */
257extern void xfs_buf_rele(struct xfs_buf *);
258
259/* Locking and Unlocking Buffers */
260extern int xfs_buf_trylock(struct xfs_buf *);
261extern void xfs_buf_lock(struct xfs_buf *);
262extern void xfs_buf_unlock(struct xfs_buf *);
263#define xfs_buf_islocked(bp) \
264 ((bp)->b_sema.count <= 0)
265
266static inline void xfs_buf_relse(struct xfs_buf *bp)
267{
268 xfs_buf_unlock(bp);
269 xfs_buf_rele(bp);
270}
271
272/* Buffer Read and Write Routines */
273extern int xfs_bwrite(struct xfs_buf *bp);
274
275extern void __xfs_buf_ioerror(struct xfs_buf *bp, int error,
276 xfs_failaddr_t failaddr);
277#define xfs_buf_ioerror(bp, err) __xfs_buf_ioerror((bp), (err), __this_address)
278extern void xfs_buf_ioerror_alert(struct xfs_buf *bp, xfs_failaddr_t fa);
279void xfs_buf_ioend_fail(struct xfs_buf *);
280void xfs_buf_zero(struct xfs_buf *bp, size_t boff, size_t bsize);
281void __xfs_buf_mark_corrupt(struct xfs_buf *bp, xfs_failaddr_t fa);
282#define xfs_buf_mark_corrupt(bp) __xfs_buf_mark_corrupt((bp), __this_address)
283
284/* Buffer Utility Routines */
285extern void *xfs_buf_offset(struct xfs_buf *, size_t);
286extern void xfs_buf_stale(struct xfs_buf *bp);
287
288/* Delayed Write Buffer Routines */
289extern void xfs_buf_delwri_cancel(struct list_head *);
290extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
291extern int xfs_buf_delwri_submit(struct list_head *);
292extern int xfs_buf_delwri_submit_nowait(struct list_head *);
293extern int xfs_buf_delwri_pushbuf(struct xfs_buf *, struct list_head *);
294
295/* Buffer Daemon Setup Routines */
296extern int xfs_buf_init(void);
297extern void xfs_buf_terminate(void);
298
299/*
300 * These macros use the IO block map rather than b_bn. b_bn is now really
301 * just for the buffer cache index for cached buffers. As IO does not use b_bn
302 * anymore, uncached buffers do not use b_bn at all and hence must modify the IO
303 * map directly. Uncached buffers are not allowed to be discontiguous, so this
304 * is safe to do.
305 *
306 * In future, uncached buffers will pass the block number directly to the io
307 * request function and hence these macros will go away at that point.
308 */
309#define XFS_BUF_ADDR(bp) ((bp)->b_maps[0].bm_bn)
310#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_maps[0].bm_bn = (xfs_daddr_t)(bno))
311
312void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref);
313
314/*
315 * If the buffer is already on the LRU, do nothing. Otherwise set the buffer
316 * up with a reference count of 0 so it will be tossed from the cache when
317 * released.
318 */
319static inline void xfs_buf_oneshot(struct xfs_buf *bp)
320{
321 if (!list_empty(&bp->b_lru) || atomic_read(&bp->b_lru_ref) > 1)
322 return;
323 atomic_set(&bp->b_lru_ref, 0);
324}
325
326static inline int xfs_buf_ispinned(struct xfs_buf *bp)
327{
328 return atomic_read(&bp->b_pin_count);
329}
330
331static inline int
332xfs_buf_verify_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
333{
334 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
335 cksum_offset);
336}
337
338static inline void
339xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
340{
341 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
342 cksum_offset);
343}
344
345/*
346 * Handling of buftargs.
347 */
348extern struct xfs_buftarg *xfs_alloc_buftarg(struct xfs_mount *,
349 struct block_device *, struct dax_device *);
350extern void xfs_free_buftarg(struct xfs_buftarg *);
351extern void xfs_buftarg_wait(struct xfs_buftarg *);
352extern void xfs_buftarg_drain(struct xfs_buftarg *);
353extern int xfs_setsize_buftarg(struct xfs_buftarg *, unsigned int);
354
355#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
356#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
357
358static inline int
359xfs_buftarg_dma_alignment(struct xfs_buftarg *bt)
360{
361 return queue_dma_alignment(bt->bt_bdev->bd_disk->queue);
362}
363
364int xfs_buf_reverify(struct xfs_buf *bp, const struct xfs_buf_ops *ops);
365bool xfs_verify_magic(struct xfs_buf *bp, __be32 dmagic);
366bool xfs_verify_magic16(struct xfs_buf *bp, __be16 dmagic);
367
368#endif /* __XFS_BUF_H__ */
1/*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
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
7 * published by the Free Software Foundation.
8 *
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.
13 *
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
17 */
18#ifndef __XFS_BUF_H__
19#define __XFS_BUF_H__
20
21#include <linux/list.h>
22#include <linux/types.h>
23#include <linux/spinlock.h>
24#include <linux/mm.h>
25#include <linux/fs.h>
26#include <linux/buffer_head.h>
27#include <linux/uio.h>
28#include <linux/list_lru.h>
29
30/*
31 * Base types
32 */
33
34#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
35
36typedef 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
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 */
48#define XBF_WRITE_FAIL (1 << 24)/* async writes have failed on this buffer */
49
50/* I/O hints for the BIO layer */
51#define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */
52#define XBF_FUA (1 << 11)/* force cache write through mode */
53#define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */
54
55/* flags used only as arguments to access routines */
56#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
57#define XBF_UNMAPPED (1 << 17)/* do not map the buffer */
58
59/* flags used only internally */
60#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
61#define _XBF_KMEM (1 << 21)/* backed by heap memory */
62#define _XBF_DELWRI_Q (1 << 22)/* buffer on a delwri queue */
63#define _XBF_COMPOUND (1 << 23)/* compound buffer */
64
65typedef unsigned int xfs_buf_flags_t;
66
67#define XFS_BUF_FLAGS \
68 { XBF_READ, "READ" }, \
69 { XBF_WRITE, "WRITE" }, \
70 { XBF_READ_AHEAD, "READ_AHEAD" }, \
71 { XBF_ASYNC, "ASYNC" }, \
72 { XBF_DONE, "DONE" }, \
73 { XBF_STALE, "STALE" }, \
74 { XBF_WRITE_FAIL, "WRITE_FAIL" }, \
75 { XBF_SYNCIO, "SYNCIO" }, \
76 { XBF_FUA, "FUA" }, \
77 { XBF_FLUSH, "FLUSH" }, \
78 { XBF_TRYLOCK, "TRYLOCK" }, /* should never be set */\
79 { XBF_UNMAPPED, "UNMAPPED" }, /* ditto */\
80 { _XBF_PAGES, "PAGES" }, \
81 { _XBF_KMEM, "KMEM" }, \
82 { _XBF_DELWRI_Q, "DELWRI_Q" }, \
83 { _XBF_COMPOUND, "COMPOUND" }
84
85
86/*
87 * Internal state flags.
88 */
89#define XFS_BSTATE_DISPOSE (1 << 0) /* buffer being discarded */
90
91/*
92 * The xfs_buftarg contains 2 notions of "sector size" -
93 *
94 * 1) The metadata sector size, which is the minimum unit and
95 * alignment of IO which will be performed by metadata operations.
96 * 2) The device logical sector size
97 *
98 * The first is specified at mkfs time, and is stored on-disk in the
99 * superblock's sb_sectsize.
100 *
101 * The latter is derived from the underlying device, and controls direct IO
102 * alignment constraints.
103 */
104typedef struct xfs_buftarg {
105 dev_t bt_dev;
106 struct block_device *bt_bdev;
107 struct backing_dev_info *bt_bdi;
108 struct xfs_mount *bt_mount;
109 unsigned int bt_meta_sectorsize;
110 size_t bt_meta_sectormask;
111 size_t bt_logical_sectorsize;
112 size_t bt_logical_sectormask;
113
114 /* LRU control structures */
115 struct shrinker bt_shrinker;
116 struct list_lru bt_lru;
117} xfs_buftarg_t;
118
119struct xfs_buf;
120typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);
121
122
123#define XB_PAGES 2
124
125struct xfs_buf_map {
126 xfs_daddr_t bm_bn; /* block number for I/O */
127 int bm_len; /* size of I/O */
128};
129
130#define DEFINE_SINGLE_BUF_MAP(map, blkno, numblk) \
131 struct xfs_buf_map (map) = { .bm_bn = (blkno), .bm_len = (numblk) };
132
133struct xfs_buf_ops {
134 void (*verify_read)(struct xfs_buf *);
135 void (*verify_write)(struct xfs_buf *);
136};
137
138typedef struct xfs_buf {
139 /*
140 * first cacheline holds all the fields needed for an uncontended cache
141 * hit to be fully processed. The semaphore straddles the cacheline
142 * boundary, but the counter and lock sits on the first cacheline,
143 * which is the only bit that is touched if we hit the semaphore
144 * fast-path on locking.
145 */
146 struct rb_node b_rbnode; /* rbtree node */
147 xfs_daddr_t b_bn; /* block number of buffer */
148 int b_length; /* size of buffer in BBs */
149 atomic_t b_hold; /* reference count */
150 atomic_t b_lru_ref; /* lru reclaim ref count */
151 xfs_buf_flags_t b_flags; /* status flags */
152 struct semaphore b_sema; /* semaphore for lockables */
153
154 /*
155 * concurrent access to b_lru and b_lru_flags are protected by
156 * bt_lru_lock and not by b_sema
157 */
158 struct list_head b_lru; /* lru list */
159 spinlock_t b_lock; /* internal state lock */
160 unsigned int b_state; /* internal state flags */
161 wait_queue_head_t b_waiters; /* unpin waiters */
162 struct list_head b_list;
163 struct xfs_perag *b_pag; /* contains rbtree root */
164 xfs_buftarg_t *b_target; /* buffer target (device) */
165 void *b_addr; /* virtual address of buffer */
166 struct work_struct b_iodone_work;
167 xfs_buf_iodone_t b_iodone; /* I/O completion function */
168 struct completion b_iowait; /* queue for I/O waiters */
169 void *b_fspriv;
170 struct xfs_trans *b_transp;
171 struct page **b_pages; /* array of page pointers */
172 struct page *b_page_array[XB_PAGES]; /* inline pages */
173 struct xfs_buf_map *b_maps; /* compound buffer map */
174 struct xfs_buf_map __b_map; /* inline compound buffer map */
175 int b_map_count;
176 int b_io_length; /* IO size in BBs */
177 atomic_t b_pin_count; /* pin count */
178 atomic_t b_io_remaining; /* #outstanding I/O requests */
179 unsigned int b_page_count; /* size of page array */
180 unsigned int b_offset; /* page offset in first page */
181 unsigned short b_error; /* error code on I/O */
182 const struct xfs_buf_ops *b_ops;
183
184#ifdef XFS_BUF_LOCK_TRACKING
185 int b_last_holder;
186#endif
187} xfs_buf_t;
188
189/* Finding and Reading Buffers */
190struct xfs_buf *_xfs_buf_find(struct xfs_buftarg *target,
191 struct xfs_buf_map *map, int nmaps,
192 xfs_buf_flags_t flags, struct xfs_buf *new_bp);
193
194static inline struct xfs_buf *
195xfs_incore(
196 struct xfs_buftarg *target,
197 xfs_daddr_t blkno,
198 size_t numblks,
199 xfs_buf_flags_t flags)
200{
201 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
202 return _xfs_buf_find(target, &map, 1, flags, NULL);
203}
204
205struct xfs_buf *_xfs_buf_alloc(struct xfs_buftarg *target,
206 struct xfs_buf_map *map, int nmaps,
207 xfs_buf_flags_t flags);
208
209static inline struct xfs_buf *
210xfs_buf_alloc(
211 struct xfs_buftarg *target,
212 xfs_daddr_t blkno,
213 size_t numblks,
214 xfs_buf_flags_t flags)
215{
216 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
217 return _xfs_buf_alloc(target, &map, 1, flags);
218}
219
220struct xfs_buf *xfs_buf_get_map(struct xfs_buftarg *target,
221 struct xfs_buf_map *map, int nmaps,
222 xfs_buf_flags_t flags);
223struct xfs_buf *xfs_buf_read_map(struct xfs_buftarg *target,
224 struct xfs_buf_map *map, int nmaps,
225 xfs_buf_flags_t flags,
226 const struct xfs_buf_ops *ops);
227void xfs_buf_readahead_map(struct xfs_buftarg *target,
228 struct xfs_buf_map *map, int nmaps,
229 const struct xfs_buf_ops *ops);
230
231static inline struct xfs_buf *
232xfs_buf_get(
233 struct xfs_buftarg *target,
234 xfs_daddr_t blkno,
235 size_t numblks,
236 xfs_buf_flags_t flags)
237{
238 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
239 return xfs_buf_get_map(target, &map, 1, flags);
240}
241
242static inline struct xfs_buf *
243xfs_buf_read(
244 struct xfs_buftarg *target,
245 xfs_daddr_t blkno,
246 size_t numblks,
247 xfs_buf_flags_t flags,
248 const struct xfs_buf_ops *ops)
249{
250 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
251 return xfs_buf_read_map(target, &map, 1, flags, ops);
252}
253
254static inline void
255xfs_buf_readahead(
256 struct xfs_buftarg *target,
257 xfs_daddr_t blkno,
258 size_t numblks,
259 const struct xfs_buf_ops *ops)
260{
261 DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
262 return xfs_buf_readahead_map(target, &map, 1, ops);
263}
264
265struct xfs_buf *xfs_buf_get_empty(struct xfs_buftarg *target, size_t numblks);
266void xfs_buf_set_empty(struct xfs_buf *bp, size_t numblks);
267int xfs_buf_associate_memory(struct xfs_buf *bp, void *mem, size_t length);
268
269struct xfs_buf *xfs_buf_get_uncached(struct xfs_buftarg *target, size_t numblks,
270 int flags);
271struct xfs_buf *xfs_buf_read_uncached(struct xfs_buftarg *target,
272 xfs_daddr_t daddr, size_t numblks, int flags,
273 const struct xfs_buf_ops *ops);
274void xfs_buf_hold(struct xfs_buf *bp);
275
276/* Releasing Buffers */
277extern void xfs_buf_free(xfs_buf_t *);
278extern void xfs_buf_rele(xfs_buf_t *);
279
280/* Locking and Unlocking Buffers */
281extern int xfs_buf_trylock(xfs_buf_t *);
282extern void xfs_buf_lock(xfs_buf_t *);
283extern void xfs_buf_unlock(xfs_buf_t *);
284#define xfs_buf_islocked(bp) \
285 ((bp)->b_sema.count <= 0)
286
287/* Buffer Read and Write Routines */
288extern int xfs_bwrite(struct xfs_buf *bp);
289extern void xfs_buf_ioend(xfs_buf_t *, int);
290extern void xfs_buf_ioerror(xfs_buf_t *, int);
291extern void xfs_buf_ioerror_alert(struct xfs_buf *, const char *func);
292extern void xfs_buf_iorequest(xfs_buf_t *);
293extern int xfs_buf_iowait(xfs_buf_t *);
294extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *,
295 xfs_buf_rw_t);
296#define xfs_buf_zero(bp, off, len) \
297 xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
298
299extern int xfs_bioerror_relse(struct xfs_buf *);
300
301static inline int xfs_buf_geterror(xfs_buf_t *bp)
302{
303 return bp ? bp->b_error : ENOMEM;
304}
305
306/* Buffer Utility Routines */
307extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);
308
309/* Delayed Write Buffer Routines */
310extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
311extern int xfs_buf_delwri_submit(struct list_head *);
312extern int xfs_buf_delwri_submit_nowait(struct list_head *);
313
314/* Buffer Daemon Setup Routines */
315extern int xfs_buf_init(void);
316extern void xfs_buf_terminate(void);
317
318#define XFS_BUF_ZEROFLAGS(bp) \
319 ((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC| \
320 XBF_SYNCIO|XBF_FUA|XBF_FLUSH| \
321 XBF_WRITE_FAIL))
322
323void xfs_buf_stale(struct xfs_buf *bp);
324#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
325#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE)
326
327#define XFS_BUF_DONE(bp) ((bp)->b_flags |= XBF_DONE)
328#define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE)
329#define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE)
330
331#define XFS_BUF_ASYNC(bp) ((bp)->b_flags |= XBF_ASYNC)
332#define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC)
333#define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC)
334
335#define XFS_BUF_READ(bp) ((bp)->b_flags |= XBF_READ)
336#define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ)
337#define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ)
338
339#define XFS_BUF_WRITE(bp) ((bp)->b_flags |= XBF_WRITE)
340#define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE)
341#define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE)
342
343/*
344 * These macros use the IO block map rather than b_bn. b_bn is now really
345 * just for the buffer cache index for cached buffers. As IO does not use b_bn
346 * anymore, uncached buffers do not use b_bn at all and hence must modify the IO
347 * map directly. Uncached buffers are not allowed to be discontiguous, so this
348 * is safe to do.
349 *
350 * In future, uncached buffers will pass the block number directly to the io
351 * request function and hence these macros will go away at that point.
352 */
353#define XFS_BUF_ADDR(bp) ((bp)->b_maps[0].bm_bn)
354#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_maps[0].bm_bn = (xfs_daddr_t)(bno))
355
356static inline void xfs_buf_set_ref(struct xfs_buf *bp, int lru_ref)
357{
358 atomic_set(&bp->b_lru_ref, lru_ref);
359}
360
361static inline int xfs_buf_ispinned(struct xfs_buf *bp)
362{
363 return atomic_read(&bp->b_pin_count);
364}
365
366static inline void xfs_buf_relse(xfs_buf_t *bp)
367{
368 xfs_buf_unlock(bp);
369 xfs_buf_rele(bp);
370}
371
372static inline int
373xfs_buf_verify_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
374{
375 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
376 cksum_offset);
377}
378
379static inline void
380xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
381{
382 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
383 cksum_offset);
384}
385
386/*
387 * Handling of buftargs.
388 */
389extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
390 struct block_device *, int, const char *);
391extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
392extern void xfs_wait_buftarg(xfs_buftarg_t *);
393extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
394
395#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
396#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
397
398#endif /* __XFS_BUF_H__ */