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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 <asm/system.h>
25#include <linux/mm.h>
26#include <linux/fs.h>
27#include <linux/buffer_head.h>
28#include <linux/uio.h>
29
30/*
31 * Base types
32 */
33
34#define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL))
35
36#define xfs_buf_ctob(pp) ((pp) * PAGE_CACHE_SIZE)
37#define xfs_buf_btoc(dd) (((dd) + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT)
38#define xfs_buf_btoct(dd) ((dd) >> PAGE_CACHE_SHIFT)
39#define xfs_buf_poff(aa) ((aa) & ~PAGE_CACHE_MASK)
40
41typedef enum {
42 XBRW_READ = 1, /* transfer into target memory */
43 XBRW_WRITE = 2, /* transfer from target memory */
44 XBRW_ZERO = 3, /* Zero target memory */
45} xfs_buf_rw_t;
46
47#define XBF_READ (1 << 0) /* buffer intended for reading from device */
48#define XBF_WRITE (1 << 1) /* buffer intended for writing to device */
49#define XBF_READ_AHEAD (1 << 2) /* asynchronous read-ahead */
50#define XBF_MAPPED (1 << 3) /* buffer mapped (b_addr valid) */
51#define XBF_ASYNC (1 << 4) /* initiator will not wait for completion */
52#define XBF_DONE (1 << 5) /* all pages in the buffer uptodate */
53#define XBF_DELWRI (1 << 6) /* buffer has dirty pages */
54#define XBF_STALE (1 << 7) /* buffer has been staled, do not find it */
55
56/* I/O hints for the BIO layer */
57#define XBF_SYNCIO (1 << 10)/* treat this buffer as synchronous I/O */
58#define XBF_FUA (1 << 11)/* force cache write through mode */
59#define XBF_FLUSH (1 << 12)/* flush the disk cache before a write */
60
61/* flags used only as arguments to access routines */
62#define XBF_LOCK (1 << 15)/* lock requested */
63#define XBF_TRYLOCK (1 << 16)/* lock requested, but do not wait */
64#define XBF_DONT_BLOCK (1 << 17)/* do not block in current thread */
65
66/* flags used only internally */
67#define _XBF_PAGES (1 << 20)/* backed by refcounted pages */
68#define _XBF_KMEM (1 << 21)/* backed by heap memory */
69#define _XBF_DELWRI_Q (1 << 22)/* buffer on delwri queue */
70
71typedef unsigned int xfs_buf_flags_t;
72
73#define XFS_BUF_FLAGS \
74 { XBF_READ, "READ" }, \
75 { XBF_WRITE, "WRITE" }, \
76 { XBF_READ_AHEAD, "READ_AHEAD" }, \
77 { XBF_MAPPED, "MAPPED" }, \
78 { XBF_ASYNC, "ASYNC" }, \
79 { XBF_DONE, "DONE" }, \
80 { XBF_DELWRI, "DELWRI" }, \
81 { XBF_STALE, "STALE" }, \
82 { XBF_SYNCIO, "SYNCIO" }, \
83 { XBF_FUA, "FUA" }, \
84 { XBF_FLUSH, "FLUSH" }, \
85 { XBF_LOCK, "LOCK" }, /* should never be set */\
86 { XBF_TRYLOCK, "TRYLOCK" }, /* ditto */\
87 { XBF_DONT_BLOCK, "DONT_BLOCK" }, /* ditto */\
88 { _XBF_PAGES, "PAGES" }, \
89 { _XBF_KMEM, "KMEM" }, \
90 { _XBF_DELWRI_Q, "DELWRI_Q" }
91
92typedef enum {
93 XBT_FORCE_SLEEP = 0,
94 XBT_FORCE_FLUSH = 1,
95} xfs_buftarg_flags_t;
96
97typedef struct xfs_buftarg {
98 dev_t bt_dev;
99 struct block_device *bt_bdev;
100 struct backing_dev_info *bt_bdi;
101 struct xfs_mount *bt_mount;
102 unsigned int bt_bsize;
103 unsigned int bt_sshift;
104 size_t bt_smask;
105
106 /* per device delwri queue */
107 struct task_struct *bt_task;
108 struct list_head bt_delwrite_queue;
109 spinlock_t bt_delwrite_lock;
110 unsigned long bt_flags;
111
112 /* LRU control structures */
113 struct shrinker bt_shrinker;
114 struct list_head bt_lru;
115 spinlock_t bt_lru_lock;
116 unsigned int bt_lru_nr;
117} xfs_buftarg_t;
118
119struct xfs_buf;
120typedef void (*xfs_buf_iodone_t)(struct xfs_buf *);
121
122#define XB_PAGES 2
123
124typedef struct xfs_buf {
125 /*
126 * first cacheline holds all the fields needed for an uncontended cache
127 * hit to be fully processed. The semaphore straddles the cacheline
128 * boundary, but the counter and lock sits on the first cacheline,
129 * which is the only bit that is touched if we hit the semaphore
130 * fast-path on locking.
131 */
132 struct rb_node b_rbnode; /* rbtree node */
133 xfs_off_t b_file_offset; /* offset in file */
134 size_t b_buffer_length;/* size of buffer in bytes */
135 atomic_t b_hold; /* reference count */
136 atomic_t b_lru_ref; /* lru reclaim ref count */
137 xfs_buf_flags_t b_flags; /* status flags */
138 struct semaphore b_sema; /* semaphore for lockables */
139
140 struct list_head b_lru; /* lru list */
141 wait_queue_head_t b_waiters; /* unpin waiters */
142 struct list_head b_list;
143 struct xfs_perag *b_pag; /* contains rbtree root */
144 xfs_buftarg_t *b_target; /* buffer target (device) */
145 xfs_daddr_t b_bn; /* block number for I/O */
146 size_t b_count_desired;/* desired transfer size */
147 void *b_addr; /* virtual address of buffer */
148 struct work_struct b_iodone_work;
149 xfs_buf_iodone_t b_iodone; /* I/O completion function */
150 struct completion b_iowait; /* queue for I/O waiters */
151 void *b_fspriv;
152 struct xfs_trans *b_transp;
153 struct page **b_pages; /* array of page pointers */
154 struct page *b_page_array[XB_PAGES]; /* inline pages */
155 unsigned long b_queuetime; /* time buffer was queued */
156 atomic_t b_pin_count; /* pin count */
157 atomic_t b_io_remaining; /* #outstanding I/O requests */
158 unsigned int b_page_count; /* size of page array */
159 unsigned int b_offset; /* page offset in first page */
160 unsigned short b_error; /* error code on I/O */
161#ifdef XFS_BUF_LOCK_TRACKING
162 int b_last_holder;
163#endif
164} xfs_buf_t;
165
166
167/* Finding and Reading Buffers */
168extern xfs_buf_t *_xfs_buf_find(xfs_buftarg_t *, xfs_off_t, size_t,
169 xfs_buf_flags_t, xfs_buf_t *);
170#define xfs_incore(buftarg,blkno,len,lockit) \
171 _xfs_buf_find(buftarg, blkno ,len, lockit, NULL)
172
173extern xfs_buf_t *xfs_buf_get(xfs_buftarg_t *, xfs_off_t, size_t,
174 xfs_buf_flags_t);
175extern xfs_buf_t *xfs_buf_read(xfs_buftarg_t *, xfs_off_t, size_t,
176 xfs_buf_flags_t);
177
178extern xfs_buf_t *xfs_buf_get_empty(size_t, xfs_buftarg_t *);
179extern void xfs_buf_set_empty(struct xfs_buf *bp, size_t len);
180extern xfs_buf_t *xfs_buf_get_uncached(struct xfs_buftarg *, size_t, int);
181extern int xfs_buf_associate_memory(xfs_buf_t *, void *, size_t);
182extern void xfs_buf_hold(xfs_buf_t *);
183extern void xfs_buf_readahead(xfs_buftarg_t *, xfs_off_t, size_t);
184struct xfs_buf *xfs_buf_read_uncached(struct xfs_mount *mp,
185 struct xfs_buftarg *target,
186 xfs_daddr_t daddr, size_t length, int flags);
187
188/* Releasing Buffers */
189extern void xfs_buf_free(xfs_buf_t *);
190extern void xfs_buf_rele(xfs_buf_t *);
191
192/* Locking and Unlocking Buffers */
193extern int xfs_buf_trylock(xfs_buf_t *);
194extern void xfs_buf_lock(xfs_buf_t *);
195extern void xfs_buf_unlock(xfs_buf_t *);
196#define xfs_buf_islocked(bp) \
197 ((bp)->b_sema.count <= 0)
198
199/* Buffer Read and Write Routines */
200extern int xfs_bwrite(struct xfs_mount *mp, struct xfs_buf *bp);
201extern void xfs_bdwrite(void *mp, xfs_buf_t *bp);
202
203extern void xfsbdstrat(struct xfs_mount *, struct xfs_buf *);
204extern int xfs_bdstrat_cb(struct xfs_buf *);
205
206extern void xfs_buf_ioend(xfs_buf_t *, int);
207extern void xfs_buf_ioerror(xfs_buf_t *, int);
208extern int xfs_buf_iorequest(xfs_buf_t *);
209extern int xfs_buf_iowait(xfs_buf_t *);
210extern void xfs_buf_iomove(xfs_buf_t *, size_t, size_t, void *,
211 xfs_buf_rw_t);
212#define xfs_buf_zero(bp, off, len) \
213 xfs_buf_iomove((bp), (off), (len), NULL, XBRW_ZERO)
214
215static inline int xfs_buf_geterror(xfs_buf_t *bp)
216{
217 return bp ? bp->b_error : ENOMEM;
218}
219
220/* Buffer Utility Routines */
221extern xfs_caddr_t xfs_buf_offset(xfs_buf_t *, size_t);
222
223/* Delayed Write Buffer Routines */
224extern void xfs_buf_delwri_dequeue(xfs_buf_t *);
225extern void xfs_buf_delwri_promote(xfs_buf_t *);
226
227/* Buffer Daemon Setup Routines */
228extern int xfs_buf_init(void);
229extern void xfs_buf_terminate(void);
230
231static inline const char *
232xfs_buf_target_name(struct xfs_buftarg *target)
233{
234 static char __b[BDEVNAME_SIZE];
235
236 return bdevname(target->bt_bdev, __b);
237}
238
239
240#define XFS_BUF_ZEROFLAGS(bp) \
241 ((bp)->b_flags &= ~(XBF_READ|XBF_WRITE|XBF_ASYNC|XBF_DELWRI| \
242 XBF_SYNCIO|XBF_FUA|XBF_FLUSH))
243
244void xfs_buf_stale(struct xfs_buf *bp);
245#define XFS_BUF_STALE(bp) xfs_buf_stale(bp);
246#define XFS_BUF_UNSTALE(bp) ((bp)->b_flags &= ~XBF_STALE)
247#define XFS_BUF_ISSTALE(bp) ((bp)->b_flags & XBF_STALE)
248#define XFS_BUF_SUPER_STALE(bp) do { \
249 XFS_BUF_STALE(bp); \
250 xfs_buf_delwri_dequeue(bp); \
251 XFS_BUF_DONE(bp); \
252 } while (0)
253
254#define XFS_BUF_DELAYWRITE(bp) ((bp)->b_flags |= XBF_DELWRI)
255#define XFS_BUF_UNDELAYWRITE(bp) xfs_buf_delwri_dequeue(bp)
256#define XFS_BUF_ISDELAYWRITE(bp) ((bp)->b_flags & XBF_DELWRI)
257
258#define XFS_BUF_DONE(bp) ((bp)->b_flags |= XBF_DONE)
259#define XFS_BUF_UNDONE(bp) ((bp)->b_flags &= ~XBF_DONE)
260#define XFS_BUF_ISDONE(bp) ((bp)->b_flags & XBF_DONE)
261
262#define XFS_BUF_ASYNC(bp) ((bp)->b_flags |= XBF_ASYNC)
263#define XFS_BUF_UNASYNC(bp) ((bp)->b_flags &= ~XBF_ASYNC)
264#define XFS_BUF_ISASYNC(bp) ((bp)->b_flags & XBF_ASYNC)
265
266#define XFS_BUF_READ(bp) ((bp)->b_flags |= XBF_READ)
267#define XFS_BUF_UNREAD(bp) ((bp)->b_flags &= ~XBF_READ)
268#define XFS_BUF_ISREAD(bp) ((bp)->b_flags & XBF_READ)
269
270#define XFS_BUF_WRITE(bp) ((bp)->b_flags |= XBF_WRITE)
271#define XFS_BUF_UNWRITE(bp) ((bp)->b_flags &= ~XBF_WRITE)
272#define XFS_BUF_ISWRITE(bp) ((bp)->b_flags & XBF_WRITE)
273
274#define XFS_BUF_ADDR(bp) ((bp)->b_bn)
275#define XFS_BUF_SET_ADDR(bp, bno) ((bp)->b_bn = (xfs_daddr_t)(bno))
276#define XFS_BUF_OFFSET(bp) ((bp)->b_file_offset)
277#define XFS_BUF_SET_OFFSET(bp, off) ((bp)->b_file_offset = (off))
278#define XFS_BUF_COUNT(bp) ((bp)->b_count_desired)
279#define XFS_BUF_SET_COUNT(bp, cnt) ((bp)->b_count_desired = (cnt))
280#define XFS_BUF_SIZE(bp) ((bp)->b_buffer_length)
281#define XFS_BUF_SET_SIZE(bp, cnt) ((bp)->b_buffer_length = (cnt))
282
283static inline void
284xfs_buf_set_ref(
285 struct xfs_buf *bp,
286 int lru_ref)
287{
288 atomic_set(&bp->b_lru_ref, lru_ref);
289}
290#define XFS_BUF_SET_VTYPE_REF(bp, type, ref) xfs_buf_set_ref(bp, ref)
291#define XFS_BUF_SET_VTYPE(bp, type) do { } while (0)
292
293static inline int xfs_buf_ispinned(struct xfs_buf *bp)
294{
295 return atomic_read(&bp->b_pin_count);
296}
297
298#define XFS_BUF_FINISH_IOWAIT(bp) complete(&bp->b_iowait);
299
300static inline void xfs_buf_relse(xfs_buf_t *bp)
301{
302 xfs_buf_unlock(bp);
303 xfs_buf_rele(bp);
304}
305
306/*
307 * Handling of buftargs.
308 */
309extern xfs_buftarg_t *xfs_alloc_buftarg(struct xfs_mount *,
310 struct block_device *, int, const char *);
311extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *);
312extern void xfs_wait_buftarg(xfs_buftarg_t *);
313extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int);
314extern int xfs_flush_buftarg(xfs_buftarg_t *, int);
315
316#ifdef CONFIG_KDB_MODULES
317extern struct list_head *xfs_get_buftarg_list(void);
318#endif
319
320#define xfs_getsize_buftarg(buftarg) block_size((buftarg)->bt_bdev)
321#define xfs_readonly_buftarg(buftarg) bdev_read_only((buftarg)->bt_bdev)
322
323#define xfs_binval(buftarg) xfs_flush_buftarg(buftarg, 1)
324#define XFS_bflush(buftarg) xfs_flush_buftarg(buftarg, 1)
325
326#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__ */