Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 */
6
7#include <linux/sched.h>
8#include <linux/slab.h>
9#include <linux/spinlock.h>
10#include <linux/completion.h>
11#include <linux/buffer_head.h>
12#include <linux/mm.h>
13#include <linux/pagemap.h>
14#include <linux/writeback.h>
15#include <linux/swap.h>
16#include <linux/delay.h>
17#include <linux/bio.h>
18#include <linux/gfs2_ondisk.h>
19
20#include "gfs2.h"
21#include "incore.h"
22#include "glock.h"
23#include "glops.h"
24#include "inode.h"
25#include "log.h"
26#include "lops.h"
27#include "meta_io.h"
28#include "rgrp.h"
29#include "trans.h"
30#include "util.h"
31#include "trace_gfs2.h"
32
33static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc)
34{
35 struct buffer_head *bh, *head;
36 int nr_underway = 0;
37 blk_opf_t write_flags = REQ_META | REQ_PRIO | wbc_to_write_flags(wbc);
38
39 BUG_ON(!PageLocked(page));
40 BUG_ON(!page_has_buffers(page));
41
42 head = page_buffers(page);
43 bh = head;
44
45 do {
46 if (!buffer_mapped(bh))
47 continue;
48 /*
49 * If it's a fully non-blocking write attempt and we cannot
50 * lock the buffer then redirty the page. Note that this can
51 * potentially cause a busy-wait loop from flusher thread and kswapd
52 * activity, but those code paths have their own higher-level
53 * throttling.
54 */
55 if (wbc->sync_mode != WB_SYNC_NONE) {
56 lock_buffer(bh);
57 } else if (!trylock_buffer(bh)) {
58 redirty_page_for_writepage(wbc, page);
59 continue;
60 }
61 if (test_clear_buffer_dirty(bh)) {
62 mark_buffer_async_write(bh);
63 } else {
64 unlock_buffer(bh);
65 }
66 } while ((bh = bh->b_this_page) != head);
67
68 /*
69 * The page and its buffers are protected by PageWriteback(), so we can
70 * drop the bh refcounts early.
71 */
72 BUG_ON(PageWriteback(page));
73 set_page_writeback(page);
74
75 do {
76 struct buffer_head *next = bh->b_this_page;
77 if (buffer_async_write(bh)) {
78 submit_bh(REQ_OP_WRITE | write_flags, bh);
79 nr_underway++;
80 }
81 bh = next;
82 } while (bh != head);
83 unlock_page(page);
84
85 if (nr_underway == 0)
86 end_page_writeback(page);
87
88 return 0;
89}
90
91const struct address_space_operations gfs2_meta_aops = {
92 .dirty_folio = block_dirty_folio,
93 .invalidate_folio = block_invalidate_folio,
94 .writepage = gfs2_aspace_writepage,
95 .release_folio = gfs2_release_folio,
96};
97
98const struct address_space_operations gfs2_rgrp_aops = {
99 .dirty_folio = block_dirty_folio,
100 .invalidate_folio = block_invalidate_folio,
101 .writepage = gfs2_aspace_writepage,
102 .release_folio = gfs2_release_folio,
103};
104
105/**
106 * gfs2_getbuf - Get a buffer with a given address space
107 * @gl: the glock
108 * @blkno: the block number (filesystem scope)
109 * @create: 1 if the buffer should be created
110 *
111 * Returns: the buffer
112 */
113
114struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
115{
116 struct address_space *mapping = gfs2_glock2aspace(gl);
117 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
118 struct page *page;
119 struct buffer_head *bh;
120 unsigned int shift;
121 unsigned long index;
122 unsigned int bufnum;
123
124 if (mapping == NULL)
125 mapping = &sdp->sd_aspace;
126
127 shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift;
128 index = blkno >> shift; /* convert block to page */
129 bufnum = blkno - (index << shift); /* block buf index within page */
130
131 if (create) {
132 for (;;) {
133 page = grab_cache_page(mapping, index);
134 if (page)
135 break;
136 yield();
137 }
138 if (!page_has_buffers(page))
139 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
140 } else {
141 page = find_get_page_flags(mapping, index,
142 FGP_LOCK|FGP_ACCESSED);
143 if (!page)
144 return NULL;
145 if (!page_has_buffers(page)) {
146 bh = NULL;
147 goto out_unlock;
148 }
149 }
150
151 /* Locate header for our buffer within our page */
152 for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
153 /* Do nothing */;
154 get_bh(bh);
155
156 if (!buffer_mapped(bh))
157 map_bh(bh, sdp->sd_vfs, blkno);
158
159out_unlock:
160 unlock_page(page);
161 put_page(page);
162
163 return bh;
164}
165
166static void meta_prep_new(struct buffer_head *bh)
167{
168 struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
169
170 lock_buffer(bh);
171 clear_buffer_dirty(bh);
172 set_buffer_uptodate(bh);
173 unlock_buffer(bh);
174
175 mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
176}
177
178/**
179 * gfs2_meta_new - Get a block
180 * @gl: The glock associated with this block
181 * @blkno: The block number
182 *
183 * Returns: The buffer
184 */
185
186struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
187{
188 struct buffer_head *bh;
189 bh = gfs2_getbuf(gl, blkno, CREATE);
190 meta_prep_new(bh);
191 return bh;
192}
193
194static void gfs2_meta_read_endio(struct bio *bio)
195{
196 struct bio_vec *bvec;
197 struct bvec_iter_all iter_all;
198
199 bio_for_each_segment_all(bvec, bio, iter_all) {
200 struct page *page = bvec->bv_page;
201 struct buffer_head *bh = page_buffers(page);
202 unsigned int len = bvec->bv_len;
203
204 while (bh_offset(bh) < bvec->bv_offset)
205 bh = bh->b_this_page;
206 do {
207 struct buffer_head *next = bh->b_this_page;
208 len -= bh->b_size;
209 bh->b_end_io(bh, !bio->bi_status);
210 bh = next;
211 } while (bh && len);
212 }
213 bio_put(bio);
214}
215
216/*
217 * Submit several consecutive buffer head I/O requests as a single bio I/O
218 * request. (See submit_bh_wbc.)
219 */
220static void gfs2_submit_bhs(blk_opf_t opf, struct buffer_head *bhs[], int num)
221{
222 while (num > 0) {
223 struct buffer_head *bh = *bhs;
224 struct bio *bio;
225
226 bio = bio_alloc(bh->b_bdev, num, opf, GFP_NOIO);
227 bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
228 while (num > 0) {
229 bh = *bhs;
230 if (!bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh))) {
231 BUG_ON(bio->bi_iter.bi_size == 0);
232 break;
233 }
234 bhs++;
235 num--;
236 }
237 bio->bi_end_io = gfs2_meta_read_endio;
238 submit_bio(bio);
239 }
240}
241
242/**
243 * gfs2_meta_read - Read a block from disk
244 * @gl: The glock covering the block
245 * @blkno: The block number
246 * @flags: flags
247 * @rahead: Do read-ahead
248 * @bhp: the place where the buffer is returned (NULL on failure)
249 *
250 * Returns: errno
251 */
252
253int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
254 int rahead, struct buffer_head **bhp)
255{
256 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
257 struct buffer_head *bh, *bhs[2];
258 int num = 0;
259
260 if (unlikely(gfs2_withdrawn(sdp)) && !gfs2_withdraw_in_prog(sdp)) {
261 *bhp = NULL;
262 return -EIO;
263 }
264
265 *bhp = bh = gfs2_getbuf(gl, blkno, CREATE);
266
267 lock_buffer(bh);
268 if (buffer_uptodate(bh)) {
269 unlock_buffer(bh);
270 flags &= ~DIO_WAIT;
271 } else {
272 bh->b_end_io = end_buffer_read_sync;
273 get_bh(bh);
274 bhs[num++] = bh;
275 }
276
277 if (rahead) {
278 bh = gfs2_getbuf(gl, blkno + 1, CREATE);
279
280 lock_buffer(bh);
281 if (buffer_uptodate(bh)) {
282 unlock_buffer(bh);
283 brelse(bh);
284 } else {
285 bh->b_end_io = end_buffer_read_sync;
286 bhs[num++] = bh;
287 }
288 }
289
290 gfs2_submit_bhs(REQ_OP_READ | REQ_META | REQ_PRIO, bhs, num);
291 if (!(flags & DIO_WAIT))
292 return 0;
293
294 bh = *bhp;
295 wait_on_buffer(bh);
296 if (unlikely(!buffer_uptodate(bh))) {
297 struct gfs2_trans *tr = current->journal_info;
298 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags))
299 gfs2_io_error_bh_wd(sdp, bh);
300 brelse(bh);
301 *bhp = NULL;
302 return -EIO;
303 }
304
305 return 0;
306}
307
308/**
309 * gfs2_meta_wait - Reread a block from disk
310 * @sdp: the filesystem
311 * @bh: The block to wait for
312 *
313 * Returns: errno
314 */
315
316int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
317{
318 if (unlikely(gfs2_withdrawn(sdp)) && !gfs2_withdraw_in_prog(sdp))
319 return -EIO;
320
321 wait_on_buffer(bh);
322
323 if (!buffer_uptodate(bh)) {
324 struct gfs2_trans *tr = current->journal_info;
325 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags))
326 gfs2_io_error_bh_wd(sdp, bh);
327 return -EIO;
328 }
329 if (unlikely(gfs2_withdrawn(sdp)) && !gfs2_withdraw_in_prog(sdp))
330 return -EIO;
331
332 return 0;
333}
334
335void gfs2_remove_from_journal(struct buffer_head *bh, int meta)
336{
337 struct address_space *mapping = bh->b_page->mapping;
338 struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
339 struct gfs2_bufdata *bd = bh->b_private;
340 struct gfs2_trans *tr = current->journal_info;
341 int was_pinned = 0;
342
343 if (test_clear_buffer_pinned(bh)) {
344 trace_gfs2_pin(bd, 0);
345 atomic_dec(&sdp->sd_log_pinned);
346 list_del_init(&bd->bd_list);
347 if (meta == REMOVE_META)
348 tr->tr_num_buf_rm++;
349 else
350 tr->tr_num_databuf_rm++;
351 set_bit(TR_TOUCHED, &tr->tr_flags);
352 was_pinned = 1;
353 brelse(bh);
354 }
355 if (bd) {
356 if (bd->bd_tr) {
357 gfs2_trans_add_revoke(sdp, bd);
358 } else if (was_pinned) {
359 bh->b_private = NULL;
360 kmem_cache_free(gfs2_bufdata_cachep, bd);
361 } else if (!list_empty(&bd->bd_ail_st_list) &&
362 !list_empty(&bd->bd_ail_gl_list)) {
363 gfs2_remove_from_ail(bd);
364 }
365 }
366 clear_buffer_dirty(bh);
367 clear_buffer_uptodate(bh);
368}
369
370/**
371 * gfs2_ail1_wipe - remove deleted/freed buffers from the ail1 list
372 * @sdp: superblock
373 * @bstart: starting block address of buffers to remove
374 * @blen: length of buffers to be removed
375 *
376 * This function is called from gfs2_journal wipe, whose job is to remove
377 * buffers, corresponding to deleted blocks, from the journal. If we find any
378 * bufdata elements on the system ail1 list, they haven't been written to
379 * the journal yet. So we remove them.
380 */
381static void gfs2_ail1_wipe(struct gfs2_sbd *sdp, u64 bstart, u32 blen)
382{
383 struct gfs2_trans *tr, *s;
384 struct gfs2_bufdata *bd, *bs;
385 struct buffer_head *bh;
386 u64 end = bstart + blen;
387
388 gfs2_log_lock(sdp);
389 spin_lock(&sdp->sd_ail_lock);
390 list_for_each_entry_safe(tr, s, &sdp->sd_ail1_list, tr_list) {
391 list_for_each_entry_safe(bd, bs, &tr->tr_ail1_list,
392 bd_ail_st_list) {
393 bh = bd->bd_bh;
394 if (bh->b_blocknr < bstart || bh->b_blocknr >= end)
395 continue;
396
397 gfs2_remove_from_journal(bh, REMOVE_JDATA);
398 }
399 }
400 spin_unlock(&sdp->sd_ail_lock);
401 gfs2_log_unlock(sdp);
402}
403
404static struct buffer_head *gfs2_getjdatabuf(struct gfs2_inode *ip, u64 blkno)
405{
406 struct address_space *mapping = ip->i_inode.i_mapping;
407 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
408 struct page *page;
409 struct buffer_head *bh;
410 unsigned int shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift;
411 unsigned long index = blkno >> shift; /* convert block to page */
412 unsigned int bufnum = blkno - (index << shift);
413
414 page = find_get_page_flags(mapping, index, FGP_LOCK|FGP_ACCESSED);
415 if (!page)
416 return NULL;
417 if (!page_has_buffers(page)) {
418 unlock_page(page);
419 put_page(page);
420 return NULL;
421 }
422 /* Locate header for our buffer within our page */
423 for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
424 /* Do nothing */;
425 get_bh(bh);
426 unlock_page(page);
427 put_page(page);
428 return bh;
429}
430
431/**
432 * gfs2_journal_wipe - make inode's buffers so they aren't dirty/pinned anymore
433 * @ip: the inode who owns the buffers
434 * @bstart: the first buffer in the run
435 * @blen: the number of buffers in the run
436 *
437 */
438
439void gfs2_journal_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
440{
441 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
442 struct buffer_head *bh;
443 int ty;
444
445 if (!ip->i_gl) {
446 /* This can only happen during incomplete inode creation. */
447 BUG_ON(!test_bit(GIF_ALLOC_FAILED, &ip->i_flags));
448 return;
449 }
450
451 gfs2_ail1_wipe(sdp, bstart, blen);
452 while (blen) {
453 ty = REMOVE_META;
454 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
455 if (!bh && gfs2_is_jdata(ip)) {
456 bh = gfs2_getjdatabuf(ip, bstart);
457 ty = REMOVE_JDATA;
458 }
459 if (bh) {
460 lock_buffer(bh);
461 gfs2_log_lock(sdp);
462 spin_lock(&sdp->sd_ail_lock);
463 gfs2_remove_from_journal(bh, ty);
464 spin_unlock(&sdp->sd_ail_lock);
465 gfs2_log_unlock(sdp);
466 unlock_buffer(bh);
467 brelse(bh);
468 }
469
470 bstart++;
471 blen--;
472 }
473}
474
475/**
476 * gfs2_meta_buffer - Get a metadata buffer
477 * @ip: The GFS2 inode
478 * @mtype: The block type (GFS2_METATYPE_*)
479 * @num: The block number (device relative) of the buffer
480 * @bhp: the buffer is returned here
481 *
482 * Returns: errno
483 */
484
485int gfs2_meta_buffer(struct gfs2_inode *ip, u32 mtype, u64 num,
486 struct buffer_head **bhp)
487{
488 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
489 struct gfs2_glock *gl = ip->i_gl;
490 struct buffer_head *bh;
491 int ret = 0;
492 int rahead = 0;
493
494 if (num == ip->i_no_addr)
495 rahead = ip->i_rahead;
496
497 ret = gfs2_meta_read(gl, num, DIO_WAIT, rahead, &bh);
498 if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
499 brelse(bh);
500 ret = -EIO;
501 } else {
502 *bhp = bh;
503 }
504 return ret;
505}
506
507/**
508 * gfs2_meta_ra - start readahead on an extent of a file
509 * @gl: the glock the blocks belong to
510 * @dblock: the starting disk block
511 * @extlen: the number of blocks in the extent
512 *
513 * returns: the first buffer in the extent
514 */
515
516struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
517{
518 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
519 struct buffer_head *first_bh, *bh;
520 u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
521 sdp->sd_sb.sb_bsize_shift;
522
523 BUG_ON(!extlen);
524
525 if (max_ra < 1)
526 max_ra = 1;
527 if (extlen > max_ra)
528 extlen = max_ra;
529
530 first_bh = gfs2_getbuf(gl, dblock, CREATE);
531
532 if (buffer_uptodate(first_bh))
533 goto out;
534 bh_read_nowait(first_bh, REQ_META | REQ_PRIO);
535
536 dblock++;
537 extlen--;
538
539 while (extlen) {
540 bh = gfs2_getbuf(gl, dblock, CREATE);
541
542 bh_readahead(bh, REQ_RAHEAD | REQ_META | REQ_PRIO);
543 brelse(bh);
544 dblock++;
545 extlen--;
546 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
547 goto out;
548 }
549
550 wait_on_buffer(first_bh);
551out:
552 return first_bh;
553}
554
1/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13#include <linux/completion.h>
14#include <linux/buffer_head.h>
15#include <linux/mm.h>
16#include <linux/pagemap.h>
17#include <linux/writeback.h>
18#include <linux/swap.h>
19#include <linux/delay.h>
20#include <linux/bio.h>
21#include <linux/gfs2_ondisk.h>
22
23#include "gfs2.h"
24#include "incore.h"
25#include "glock.h"
26#include "glops.h"
27#include "inode.h"
28#include "log.h"
29#include "lops.h"
30#include "meta_io.h"
31#include "rgrp.h"
32#include "trans.h"
33#include "util.h"
34#include "trace_gfs2.h"
35
36static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc)
37{
38 struct buffer_head *bh, *head;
39 int nr_underway = 0;
40 int write_op = REQ_META | REQ_PRIO |
41 (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
42
43 BUG_ON(!PageLocked(page));
44 BUG_ON(!page_has_buffers(page));
45
46 head = page_buffers(page);
47 bh = head;
48
49 do {
50 if (!buffer_mapped(bh))
51 continue;
52 /*
53 * If it's a fully non-blocking write attempt and we cannot
54 * lock the buffer then redirty the page. Note that this can
55 * potentially cause a busy-wait loop from pdflush and kswapd
56 * activity, but those code paths have their own higher-level
57 * throttling.
58 */
59 if (wbc->sync_mode != WB_SYNC_NONE) {
60 lock_buffer(bh);
61 } else if (!trylock_buffer(bh)) {
62 redirty_page_for_writepage(wbc, page);
63 continue;
64 }
65 if (test_clear_buffer_dirty(bh)) {
66 mark_buffer_async_write(bh);
67 } else {
68 unlock_buffer(bh);
69 }
70 } while ((bh = bh->b_this_page) != head);
71
72 /*
73 * The page and its buffers are protected by PageWriteback(), so we can
74 * drop the bh refcounts early.
75 */
76 BUG_ON(PageWriteback(page));
77 set_page_writeback(page);
78
79 do {
80 struct buffer_head *next = bh->b_this_page;
81 if (buffer_async_write(bh)) {
82 submit_bh(write_op, bh);
83 nr_underway++;
84 }
85 bh = next;
86 } while (bh != head);
87 unlock_page(page);
88
89 if (nr_underway == 0)
90 end_page_writeback(page);
91
92 return 0;
93}
94
95const struct address_space_operations gfs2_meta_aops = {
96 .writepage = gfs2_aspace_writepage,
97 .releasepage = gfs2_releasepage,
98};
99
100/**
101 * gfs2_meta_sync - Sync all buffers associated with a glock
102 * @gl: The glock
103 *
104 */
105
106void gfs2_meta_sync(struct gfs2_glock *gl)
107{
108 struct address_space *mapping = gfs2_glock2aspace(gl);
109 int error;
110
111 filemap_fdatawrite(mapping);
112 error = filemap_fdatawait(mapping);
113
114 if (error)
115 gfs2_io_error(gl->gl_sbd);
116}
117
118/**
119 * gfs2_getbuf - Get a buffer with a given address space
120 * @gl: the glock
121 * @blkno: the block number (filesystem scope)
122 * @create: 1 if the buffer should be created
123 *
124 * Returns: the buffer
125 */
126
127struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
128{
129 struct address_space *mapping = gfs2_glock2aspace(gl);
130 struct gfs2_sbd *sdp = gl->gl_sbd;
131 struct page *page;
132 struct buffer_head *bh;
133 unsigned int shift;
134 unsigned long index;
135 unsigned int bufnum;
136
137 shift = PAGE_CACHE_SHIFT - sdp->sd_sb.sb_bsize_shift;
138 index = blkno >> shift; /* convert block to page */
139 bufnum = blkno - (index << shift); /* block buf index within page */
140
141 if (create) {
142 for (;;) {
143 page = grab_cache_page(mapping, index);
144 if (page)
145 break;
146 yield();
147 }
148 } else {
149 page = find_lock_page(mapping, index);
150 if (!page)
151 return NULL;
152 }
153
154 if (!page_has_buffers(page))
155 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
156
157 /* Locate header for our buffer within our page */
158 for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
159 /* Do nothing */;
160 get_bh(bh);
161
162 if (!buffer_mapped(bh))
163 map_bh(bh, sdp->sd_vfs, blkno);
164
165 unlock_page(page);
166 mark_page_accessed(page);
167 page_cache_release(page);
168
169 return bh;
170}
171
172static void meta_prep_new(struct buffer_head *bh)
173{
174 struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
175
176 lock_buffer(bh);
177 clear_buffer_dirty(bh);
178 set_buffer_uptodate(bh);
179 unlock_buffer(bh);
180
181 mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
182}
183
184/**
185 * gfs2_meta_new - Get a block
186 * @gl: The glock associated with this block
187 * @blkno: The block number
188 *
189 * Returns: The buffer
190 */
191
192struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
193{
194 struct buffer_head *bh;
195 bh = gfs2_getbuf(gl, blkno, CREATE);
196 meta_prep_new(bh);
197 return bh;
198}
199
200/**
201 * gfs2_meta_read - Read a block from disk
202 * @gl: The glock covering the block
203 * @blkno: The block number
204 * @flags: flags
205 * @bhp: the place where the buffer is returned (NULL on failure)
206 *
207 * Returns: errno
208 */
209
210int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
211 struct buffer_head **bhp)
212{
213 struct gfs2_sbd *sdp = gl->gl_sbd;
214 struct buffer_head *bh;
215
216 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
217 return -EIO;
218
219 *bhp = bh = gfs2_getbuf(gl, blkno, CREATE);
220
221 lock_buffer(bh);
222 if (buffer_uptodate(bh)) {
223 unlock_buffer(bh);
224 return 0;
225 }
226 bh->b_end_io = end_buffer_read_sync;
227 get_bh(bh);
228 submit_bh(READ_SYNC | REQ_META | REQ_PRIO, bh);
229 if (!(flags & DIO_WAIT))
230 return 0;
231
232 wait_on_buffer(bh);
233 if (unlikely(!buffer_uptodate(bh))) {
234 struct gfs2_trans *tr = current->journal_info;
235 if (tr && tr->tr_touched)
236 gfs2_io_error_bh(sdp, bh);
237 brelse(bh);
238 return -EIO;
239 }
240
241 return 0;
242}
243
244/**
245 * gfs2_meta_wait - Reread a block from disk
246 * @sdp: the filesystem
247 * @bh: The block to wait for
248 *
249 * Returns: errno
250 */
251
252int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
253{
254 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
255 return -EIO;
256
257 wait_on_buffer(bh);
258
259 if (!buffer_uptodate(bh)) {
260 struct gfs2_trans *tr = current->journal_info;
261 if (tr && tr->tr_touched)
262 gfs2_io_error_bh(sdp, bh);
263 return -EIO;
264 }
265 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
266 return -EIO;
267
268 return 0;
269}
270
271/**
272 * gfs2_attach_bufdata - attach a struct gfs2_bufdata structure to a buffer
273 * @gl: the glock the buffer belongs to
274 * @bh: The buffer to be attached to
275 * @meta: Flag to indicate whether its metadata or not
276 */
277
278void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
279 int meta)
280{
281 struct gfs2_bufdata *bd;
282
283 if (meta)
284 lock_page(bh->b_page);
285
286 if (bh->b_private) {
287 if (meta)
288 unlock_page(bh->b_page);
289 return;
290 }
291
292 bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
293 bd->bd_bh = bh;
294 bd->bd_gl = gl;
295
296 if (meta)
297 lops_init_le(bd, &gfs2_buf_lops);
298 else
299 lops_init_le(bd, &gfs2_databuf_lops);
300 bh->b_private = bd;
301
302 if (meta)
303 unlock_page(bh->b_page);
304}
305
306void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr, int meta)
307{
308 struct address_space *mapping = bh->b_page->mapping;
309 struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
310 struct gfs2_bufdata *bd = bh->b_private;
311
312 if (test_clear_buffer_pinned(bh)) {
313 trace_gfs2_pin(bd, 0);
314 atomic_dec(&sdp->sd_log_pinned);
315 list_del_init(&bd->bd_list);
316 if (meta) {
317 gfs2_assert_warn(sdp, sdp->sd_log_num_buf);
318 sdp->sd_log_num_buf--;
319 tr->tr_num_buf_rm++;
320 } else {
321 gfs2_assert_warn(sdp, sdp->sd_log_num_databuf);
322 sdp->sd_log_num_databuf--;
323 tr->tr_num_databuf_rm++;
324 }
325 tr->tr_touched = 1;
326 brelse(bh);
327 }
328 if (bd) {
329 spin_lock(&sdp->sd_ail_lock);
330 if (bd->bd_ail) {
331 gfs2_remove_from_ail(bd);
332 bh->b_private = NULL;
333 bd->bd_bh = NULL;
334 bd->bd_blkno = bh->b_blocknr;
335 gfs2_trans_add_revoke(sdp, bd);
336 }
337 spin_unlock(&sdp->sd_ail_lock);
338 }
339 clear_buffer_dirty(bh);
340 clear_buffer_uptodate(bh);
341}
342
343/**
344 * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore
345 * @ip: the inode who owns the buffers
346 * @bstart: the first buffer in the run
347 * @blen: the number of buffers in the run
348 *
349 */
350
351void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
352{
353 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
354 struct buffer_head *bh;
355
356 while (blen) {
357 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
358 if (bh) {
359 lock_buffer(bh);
360 gfs2_log_lock(sdp);
361 gfs2_remove_from_journal(bh, current->journal_info, 1);
362 gfs2_log_unlock(sdp);
363 unlock_buffer(bh);
364 brelse(bh);
365 }
366
367 bstart++;
368 blen--;
369 }
370}
371
372/**
373 * gfs2_meta_indirect_buffer - Get a metadata buffer
374 * @ip: The GFS2 inode
375 * @height: The level of this buf in the metadata (indir addr) tree (if any)
376 * @num: The block number (device relative) of the buffer
377 * @bhp: the buffer is returned here
378 *
379 * Returns: errno
380 */
381
382int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
383 struct buffer_head **bhp)
384{
385 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
386 struct gfs2_glock *gl = ip->i_gl;
387 struct buffer_head *bh;
388 int ret = 0;
389 u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
390
391 ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh);
392 if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
393 brelse(bh);
394 ret = -EIO;
395 }
396 *bhp = bh;
397 return ret;
398}
399
400/**
401 * gfs2_meta_ra - start readahead on an extent of a file
402 * @gl: the glock the blocks belong to
403 * @dblock: the starting disk block
404 * @extlen: the number of blocks in the extent
405 *
406 * returns: the first buffer in the extent
407 */
408
409struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
410{
411 struct gfs2_sbd *sdp = gl->gl_sbd;
412 struct buffer_head *first_bh, *bh;
413 u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
414 sdp->sd_sb.sb_bsize_shift;
415
416 BUG_ON(!extlen);
417
418 if (max_ra < 1)
419 max_ra = 1;
420 if (extlen > max_ra)
421 extlen = max_ra;
422
423 first_bh = gfs2_getbuf(gl, dblock, CREATE);
424
425 if (buffer_uptodate(first_bh))
426 goto out;
427 if (!buffer_locked(first_bh))
428 ll_rw_block(READ_SYNC | REQ_META, 1, &first_bh);
429
430 dblock++;
431 extlen--;
432
433 while (extlen) {
434 bh = gfs2_getbuf(gl, dblock, CREATE);
435
436 if (!buffer_uptodate(bh) && !buffer_locked(bh))
437 ll_rw_block(READA | REQ_META, 1, &bh);
438 brelse(bh);
439 dblock++;
440 extlen--;
441 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
442 goto out;
443 }
444
445 wait_on_buffer(first_bh);
446out:
447 return first_bh;
448}
449