Commit | Line | Data |
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7336d0e6 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
b3b94faa DT |
2 | /* |
3 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
091806ed | 4 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
b3b94faa DT |
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> | |
2e565bb6 | 17 | #include <linux/bio.h> |
5c676f6d | 18 | #include <linux/gfs2_ondisk.h> |
b3b94faa DT |
19 | |
20 | #include "gfs2.h" | |
5c676f6d | 21 | #include "incore.h" |
b3b94faa DT |
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" | |
5c676f6d | 30 | #include "util.h" |
627c10b7 | 31 | #include "trace_gfs2.h" |
b3b94faa | 32 | |
4a0f9a32 | 33 | static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc) |
b3b94faa | 34 | { |
50fabd42 | 35 | struct folio *folio = page_folio(page); |
4a0f9a32 SW |
36 | struct buffer_head *bh, *head; |
37 | int nr_underway = 0; | |
67688c08 | 38 | blk_opf_t write_flags = REQ_META | REQ_PRIO | wbc_to_write_flags(wbc); |
b3b94faa | 39 | |
50fabd42 | 40 | BUG_ON(!folio_test_locked(folio)); |
4a0f9a32 | 41 | |
50fabd42 | 42 | head = folio_buffers(folio); |
4a0f9a32 SW |
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 | |
e76e0ec9 | 51 | * potentially cause a busy-wait loop from flusher thread and kswapd |
4a0f9a32 SW |
52 | * activity, but those code paths have their own higher-level |
53 | * throttling. | |
54 | */ | |
1b430bee | 55 | if (wbc->sync_mode != WB_SYNC_NONE) { |
4a0f9a32 SW |
56 | lock_buffer(bh); |
57 | } else if (!trylock_buffer(bh)) { | |
50fabd42 | 58 | folio_redirty_for_writepage(wbc, folio); |
4a0f9a32 SW |
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 | */ | |
50fabd42 MWO |
72 | BUG_ON(folio_test_writeback(folio)); |
73 | folio_start_writeback(folio); | |
4a0f9a32 SW |
74 | |
75 | do { | |
76 | struct buffer_head *next = bh->b_this_page; | |
77 | if (buffer_async_write(bh)) { | |
1420c4a5 | 78 | submit_bh(REQ_OP_WRITE | write_flags, bh); |
4a0f9a32 SW |
79 | nr_underway++; |
80 | } | |
81 | bh = next; | |
82 | } while (bh != head); | |
50fabd42 | 83 | folio_unlock(folio); |
4a0f9a32 | 84 | |
4a0f9a32 | 85 | if (nr_underway == 0) |
50fabd42 | 86 | folio_end_writeback(folio); |
4a0f9a32 | 87 | |
eaefbf96 | 88 | return 0; |
b3b94faa DT |
89 | } |
90 | ||
009d8518 | 91 | const struct address_space_operations gfs2_meta_aops = { |
e621900a | 92 | .dirty_folio = block_dirty_folio, |
7ba13abb | 93 | .invalidate_folio = block_invalidate_folio, |
b3b94faa | 94 | .writepage = gfs2_aspace_writepage, |
e45c20d1 | 95 | .release_folio = gfs2_release_folio, |
b3b94faa DT |
96 | }; |
97 | ||
1b2ad412 | 98 | const struct address_space_operations gfs2_rgrp_aops = { |
e621900a | 99 | .dirty_folio = block_dirty_folio, |
7ba13abb | 100 | .invalidate_folio = block_invalidate_folio, |
1b2ad412 | 101 | .writepage = gfs2_aspace_writepage, |
e45c20d1 | 102 | .release_folio = gfs2_release_folio, |
1b2ad412 SW |
103 | }; |
104 | ||
b3b94faa | 105 | /** |
6802e340 | 106 | * gfs2_getbuf - Get a buffer with a given address space |
cb4c0313 | 107 | * @gl: the glock |
b3b94faa DT |
108 | * @blkno: the block number (filesystem scope) |
109 | * @create: 1 if the buffer should be created | |
110 | * | |
111 | * Returns: the buffer | |
112 | */ | |
113 | ||
6802e340 | 114 | struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create) |
b3b94faa | 115 | { |
009d8518 | 116 | struct address_space *mapping = gfs2_glock2aspace(gl); |
15562c43 | 117 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
0eb75179 | 118 | struct folio *folio; |
b3b94faa DT |
119 | struct buffer_head *bh; |
120 | unsigned int shift; | |
121 | unsigned long index; | |
122 | unsigned int bufnum; | |
123 | ||
70d4ee94 SW |
124 | if (mapping == NULL) |
125 | mapping = &sdp->sd_aspace; | |
126 | ||
09cbfeaf | 127 | shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift; |
b3b94faa DT |
128 | index = blkno >> shift; /* convert block to page */ |
129 | bufnum = blkno - (index << shift); /* block buf index within page */ | |
130 | ||
131 | if (create) { | |
0eb75179 MWO |
132 | folio = __filemap_get_folio(mapping, index, |
133 | FGP_LOCK | FGP_ACCESSED | FGP_CREAT, | |
134 | mapping_gfp_mask(mapping) | __GFP_NOFAIL); | |
135 | bh = folio_buffers(folio); | |
136 | if (!bh) | |
0a88810d | 137 | bh = create_empty_buffers(folio, |
0eb75179 | 138 | sdp->sd_sb.sb_bsize, 0); |
b3b94faa | 139 | } else { |
0eb75179 MWO |
140 | folio = __filemap_get_folio(mapping, index, |
141 | FGP_LOCK | FGP_ACCESSED, 0); | |
142 | if (IS_ERR(folio)) | |
b3b94faa | 143 | return NULL; |
0eb75179 | 144 | bh = folio_buffers(folio); |
b3b94faa DT |
145 | } |
146 | ||
0eb75179 MWO |
147 | if (!bh) |
148 | goto out_unlock; | |
b3b94faa | 149 | |
0eb75179 | 150 | bh = get_nth_bh(bh, bufnum); |
b3b94faa DT |
151 | if (!buffer_mapped(bh)) |
152 | map_bh(bh, sdp->sd_vfs, blkno); | |
153 | ||
e7dfab82 | 154 | out_unlock: |
0eb75179 MWO |
155 | folio_unlock(folio); |
156 | folio_put(folio); | |
b3b94faa DT |
157 | |
158 | return bh; | |
159 | } | |
160 | ||
161 | static void meta_prep_new(struct buffer_head *bh) | |
162 | { | |
163 | struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data; | |
164 | ||
165 | lock_buffer(bh); | |
166 | clear_buffer_dirty(bh); | |
167 | set_buffer_uptodate(bh); | |
168 | unlock_buffer(bh); | |
169 | ||
170 | mh->mh_magic = cpu_to_be32(GFS2_MAGIC); | |
171 | } | |
172 | ||
173 | /** | |
174 | * gfs2_meta_new - Get a block | |
175 | * @gl: The glock associated with this block | |
176 | * @blkno: The block number | |
177 | * | |
178 | * Returns: The buffer | |
179 | */ | |
180 | ||
cd915493 | 181 | struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno) |
b3b94faa DT |
182 | { |
183 | struct buffer_head *bh; | |
6802e340 | 184 | bh = gfs2_getbuf(gl, blkno, CREATE); |
b3b94faa DT |
185 | meta_prep_new(bh); |
186 | return bh; | |
187 | } | |
188 | ||
39b0555f | 189 | static void gfs2_meta_read_endio(struct bio *bio) |
c8d57703 | 190 | { |
39b0555f | 191 | struct bio_vec *bvec; |
6dc4f100 | 192 | struct bvec_iter_all iter_all; |
39b0555f | 193 | |
2b070cfe | 194 | bio_for_each_segment_all(bvec, bio, iter_all) { |
39b0555f AG |
195 | struct page *page = bvec->bv_page; |
196 | struct buffer_head *bh = page_buffers(page); | |
197 | unsigned int len = bvec->bv_len; | |
198 | ||
199 | while (bh_offset(bh) < bvec->bv_offset) | |
200 | bh = bh->b_this_page; | |
201 | do { | |
202 | struct buffer_head *next = bh->b_this_page; | |
203 | len -= bh->b_size; | |
4e4cbee9 | 204 | bh->b_end_io(bh, !bio->bi_status); |
39b0555f AG |
205 | bh = next; |
206 | } while (bh && len); | |
207 | } | |
208 | bio_put(bio); | |
209 | } | |
c8d57703 | 210 | |
39b0555f AG |
211 | /* |
212 | * Submit several consecutive buffer head I/O requests as a single bio I/O | |
213 | * request. (See submit_bh_wbc.) | |
214 | */ | |
67688c08 | 215 | static void gfs2_submit_bhs(blk_opf_t opf, struct buffer_head *bhs[], int num) |
39b0555f | 216 | { |
23e5671a AG |
217 | while (num > 0) { |
218 | struct buffer_head *bh = *bhs; | |
219 | struct bio *bio; | |
220 | ||
67688c08 | 221 | bio = bio_alloc(bh->b_bdev, num, opf, GFP_NOIO); |
23e5671a | 222 | bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); |
23e5671a AG |
223 | while (num > 0) { |
224 | bh = *bhs; | |
225 | if (!bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh))) { | |
226 | BUG_ON(bio->bi_iter.bi_size == 0); | |
227 | break; | |
228 | } | |
229 | bhs++; | |
230 | num--; | |
231 | } | |
232 | bio->bi_end_io = gfs2_meta_read_endio; | |
23e5671a | 233 | submit_bio(bio); |
c8d57703 | 234 | } |
c8d57703 AG |
235 | } |
236 | ||
b3b94faa DT |
237 | /** |
238 | * gfs2_meta_read - Read a block from disk | |
239 | * @gl: The glock covering the block | |
240 | * @blkno: The block number | |
7276b3b0 | 241 | * @flags: flags |
c551f66c | 242 | * @rahead: Do read-ahead |
b3b94faa DT |
243 | * @bhp: the place where the buffer is returned (NULL on failure) |
244 | * | |
245 | * Returns: errno | |
246 | */ | |
247 | ||
cd915493 | 248 | int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags, |
c8d57703 | 249 | int rahead, struct buffer_head **bhp) |
b3b94faa | 250 | { |
15562c43 | 251 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
39b0555f AG |
252 | struct buffer_head *bh, *bhs[2]; |
253 | int num = 0; | |
c969f58c | 254 | |
4d927b03 AG |
255 | if (gfs2_withdrawing_or_withdrawn(sdp) && |
256 | !gfs2_withdraw_in_prog(sdp)) { | |
44b8db13 | 257 | *bhp = NULL; |
c969f58c | 258 | return -EIO; |
44b8db13 | 259 | } |
c969f58c SW |
260 | |
261 | *bhp = bh = gfs2_getbuf(gl, blkno, CREATE); | |
262 | ||
263 | lock_buffer(bh); | |
264 | if (buffer_uptodate(bh)) { | |
265 | unlock_buffer(bh); | |
39b0555f AG |
266 | flags &= ~DIO_WAIT; |
267 | } else { | |
268 | bh->b_end_io = end_buffer_read_sync; | |
269 | get_bh(bh); | |
270 | bhs[num++] = bh; | |
c969f58c | 271 | } |
39b0555f AG |
272 | |
273 | if (rahead) { | |
274 | bh = gfs2_getbuf(gl, blkno + 1, CREATE); | |
275 | ||
276 | lock_buffer(bh); | |
277 | if (buffer_uptodate(bh)) { | |
278 | unlock_buffer(bh); | |
279 | brelse(bh); | |
280 | } else { | |
281 | bh->b_end_io = end_buffer_read_sync; | |
282 | bhs[num++] = bh; | |
283 | } | |
284 | } | |
285 | ||
67688c08 | 286 | gfs2_submit_bhs(REQ_OP_READ | REQ_META | REQ_PRIO, bhs, num); |
c969f58c SW |
287 | if (!(flags & DIO_WAIT)) |
288 | return 0; | |
289 | ||
39b0555f | 290 | bh = *bhp; |
c969f58c SW |
291 | wait_on_buffer(bh); |
292 | if (unlikely(!buffer_uptodate(bh))) { | |
293 | struct gfs2_trans *tr = current->journal_info; | |
9862ca05 | 294 | if (tr && test_bit(TR_TOUCHED, &tr->tr_flags)) |
9e1a9ecd | 295 | gfs2_io_error_bh_wd(sdp, bh); |
c969f58c | 296 | brelse(bh); |
44b8db13 | 297 | *bhp = NULL; |
c969f58c | 298 | return -EIO; |
7276b3b0 | 299 | } |
b3b94faa | 300 | |
7276b3b0 | 301 | return 0; |
b3b94faa DT |
302 | } |
303 | ||
304 | /** | |
7276b3b0 | 305 | * gfs2_meta_wait - Reread a block from disk |
b3b94faa | 306 | * @sdp: the filesystem |
7276b3b0 | 307 | * @bh: The block to wait for |
b3b94faa DT |
308 | * |
309 | * Returns: errno | |
310 | */ | |
311 | ||
7276b3b0 | 312 | int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh) |
b3b94faa | 313 | { |
4d927b03 AG |
314 | if (gfs2_withdrawing_or_withdrawn(sdp) && |
315 | !gfs2_withdraw_in_prog(sdp)) | |
b3b94faa DT |
316 | return -EIO; |
317 | ||
7276b3b0 | 318 | wait_on_buffer(bh); |
b3b94faa | 319 | |
7276b3b0 SW |
320 | if (!buffer_uptodate(bh)) { |
321 | struct gfs2_trans *tr = current->journal_info; | |
9862ca05 | 322 | if (tr && test_bit(TR_TOUCHED, &tr->tr_flags)) |
9e1a9ecd | 323 | gfs2_io_error_bh_wd(sdp, bh); |
7276b3b0 | 324 | return -EIO; |
b3b94faa | 325 | } |
4d927b03 AG |
326 | if (gfs2_withdrawing_or_withdrawn(sdp) && |
327 | !gfs2_withdraw_in_prog(sdp)) | |
7276b3b0 | 328 | return -EIO; |
b3b94faa DT |
329 | |
330 | return 0; | |
331 | } | |
332 | ||
68cd4ce2 | 333 | void gfs2_remove_from_journal(struct buffer_head *bh, int meta) |
16615be1 | 334 | { |
11551cf1 | 335 | struct address_space *mapping = bh->b_folio->mapping; |
009d8518 | 336 | struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping); |
16615be1 | 337 | struct gfs2_bufdata *bd = bh->b_private; |
68cd4ce2 | 338 | struct gfs2_trans *tr = current->journal_info; |
502be2a3 | 339 | int was_pinned = 0; |
009d8518 | 340 | |
16615be1 | 341 | if (test_clear_buffer_pinned(bh)) { |
627c10b7 | 342 | trace_gfs2_pin(bd, 0); |
5e687eac | 343 | atomic_dec(&sdp->sd_log_pinned); |
c0752aa7 | 344 | list_del_init(&bd->bd_list); |
68cd4ce2 | 345 | if (meta == REMOVE_META) |
16615be1 | 346 | tr->tr_num_buf_rm++; |
022ef4fe | 347 | else |
16615be1 | 348 | tr->tr_num_databuf_rm++; |
9862ca05 | 349 | set_bit(TR_TOUCHED, &tr->tr_flags); |
502be2a3 | 350 | was_pinned = 1; |
16615be1 SW |
351 | brelse(bh); |
352 | } | |
353 | if (bd) { | |
16ca9412 | 354 | if (bd->bd_tr) { |
16615be1 | 355 | gfs2_trans_add_revoke(sdp, bd); |
502be2a3 BP |
356 | } else if (was_pinned) { |
357 | bh->b_private = NULL; | |
358 | kmem_cache_free(gfs2_bufdata_cachep, bd); | |
68942870 BP |
359 | } else if (!list_empty(&bd->bd_ail_st_list) && |
360 | !list_empty(&bd->bd_ail_gl_list)) { | |
361 | gfs2_remove_from_ail(bd); | |
16615be1 SW |
362 | } |
363 | } | |
364 | clear_buffer_dirty(bh); | |
365 | clear_buffer_uptodate(bh); | |
366 | } | |
367 | ||
b3b94faa | 368 | /** |
68942870 BP |
369 | * gfs2_ail1_wipe - remove deleted/freed buffers from the ail1 list |
370 | * @sdp: superblock | |
371 | * @bstart: starting block address of buffers to remove | |
372 | * @blen: length of buffers to be removed | |
373 | * | |
374 | * This function is called from gfs2_journal wipe, whose job is to remove | |
375 | * buffers, corresponding to deleted blocks, from the journal. If we find any | |
376 | * bufdata elements on the system ail1 list, they haven't been written to | |
377 | * the journal yet. So we remove them. | |
378 | */ | |
379 | static void gfs2_ail1_wipe(struct gfs2_sbd *sdp, u64 bstart, u32 blen) | |
380 | { | |
381 | struct gfs2_trans *tr, *s; | |
382 | struct gfs2_bufdata *bd, *bs; | |
383 | struct buffer_head *bh; | |
384 | u64 end = bstart + blen; | |
385 | ||
386 | gfs2_log_lock(sdp); | |
387 | spin_lock(&sdp->sd_ail_lock); | |
388 | list_for_each_entry_safe(tr, s, &sdp->sd_ail1_list, tr_list) { | |
389 | list_for_each_entry_safe(bd, bs, &tr->tr_ail1_list, | |
390 | bd_ail_st_list) { | |
391 | bh = bd->bd_bh; | |
392 | if (bh->b_blocknr < bstart || bh->b_blocknr >= end) | |
393 | continue; | |
394 | ||
395 | gfs2_remove_from_journal(bh, REMOVE_JDATA); | |
396 | } | |
397 | } | |
398 | spin_unlock(&sdp->sd_ail_lock); | |
399 | gfs2_log_unlock(sdp); | |
400 | } | |
401 | ||
402 | static struct buffer_head *gfs2_getjdatabuf(struct gfs2_inode *ip, u64 blkno) | |
403 | { | |
404 | struct address_space *mapping = ip->i_inode.i_mapping; | |
405 | struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); | |
c646e573 | 406 | struct folio *folio; |
68942870 BP |
407 | struct buffer_head *bh; |
408 | unsigned int shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift; | |
409 | unsigned long index = blkno >> shift; /* convert block to page */ | |
410 | unsigned int bufnum = blkno - (index << shift); | |
411 | ||
c646e573 MWO |
412 | folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED, 0); |
413 | if (IS_ERR(folio)) | |
68942870 | 414 | return NULL; |
c646e573 MWO |
415 | bh = folio_buffers(folio); |
416 | if (bh) | |
417 | bh = get_nth_bh(bh, bufnum); | |
418 | folio_unlock(folio); | |
419 | folio_put(folio); | |
68942870 BP |
420 | return bh; |
421 | } | |
422 | ||
423 | /** | |
424 | * gfs2_journal_wipe - make inode's buffers so they aren't dirty/pinned anymore | |
b3b94faa DT |
425 | * @ip: the inode who owns the buffers |
426 | * @bstart: the first buffer in the run | |
427 | * @blen: the number of buffers in the run | |
428 | * | |
429 | */ | |
430 | ||
68942870 | 431 | void gfs2_journal_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen) |
b3b94faa | 432 | { |
feaa7bba | 433 | struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
b3b94faa | 434 | struct buffer_head *bh; |
68942870 | 435 | int ty; |
b3b94faa | 436 | |
38552ff6 AG |
437 | if (!ip->i_gl) { |
438 | /* This can only happen during incomplete inode creation. */ | |
439 | BUG_ON(!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)); | |
440 | return; | |
441 | } | |
442 | ||
68942870 | 443 | gfs2_ail1_wipe(sdp, bstart, blen); |
b3b94faa | 444 | while (blen) { |
68942870 | 445 | ty = REMOVE_META; |
6802e340 | 446 | bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE); |
68942870 BP |
447 | if (!bh && gfs2_is_jdata(ip)) { |
448 | bh = gfs2_getjdatabuf(ip, bstart); | |
449 | ty = REMOVE_JDATA; | |
450 | } | |
b3b94faa | 451 | if (bh) { |
1ad38c43 SW |
452 | lock_buffer(bh); |
453 | gfs2_log_lock(sdp); | |
68942870 BP |
454 | spin_lock(&sdp->sd_ail_lock); |
455 | gfs2_remove_from_journal(bh, ty); | |
456 | spin_unlock(&sdp->sd_ail_lock); | |
1ad38c43 | 457 | gfs2_log_unlock(sdp); |
b3b94faa | 458 | unlock_buffer(bh); |
b3b94faa DT |
459 | brelse(bh); |
460 | } | |
461 | ||
462 | bstart++; | |
463 | blen--; | |
464 | } | |
465 | } | |
466 | ||
b3b94faa | 467 | /** |
6d8da302 | 468 | * gfs2_meta_buffer - Get a metadata buffer |
b3b94faa | 469 | * @ip: The GFS2 inode |
6d8da302 | 470 | * @mtype: The block type (GFS2_METATYPE_*) |
b3b94faa | 471 | * @num: The block number (device relative) of the buffer |
b3b94faa DT |
472 | * @bhp: the buffer is returned here |
473 | * | |
b3b94faa DT |
474 | * Returns: errno |
475 | */ | |
476 | ||
6d8da302 AG |
477 | int gfs2_meta_buffer(struct gfs2_inode *ip, u32 mtype, u64 num, |
478 | struct buffer_head **bhp) | |
b3b94faa | 479 | { |
7276b3b0 SW |
480 | struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
481 | struct gfs2_glock *gl = ip->i_gl; | |
f91a0d3e SW |
482 | struct buffer_head *bh; |
483 | int ret = 0; | |
c8d57703 AG |
484 | int rahead = 0; |
485 | ||
486 | if (num == ip->i_no_addr) | |
487 | rahead = ip->i_rahead; | |
b3b94faa | 488 | |
c8d57703 | 489 | ret = gfs2_meta_read(gl, num, DIO_WAIT, rahead, &bh); |
f2f9c812 BP |
490 | if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) { |
491 | brelse(bh); | |
492 | ret = -EIO; | |
61eaadcd BP |
493 | } else { |
494 | *bhp = bh; | |
b3b94faa | 495 | } |
f91a0d3e | 496 | return ret; |
b3b94faa DT |
497 | } |
498 | ||
499 | /** | |
500 | * gfs2_meta_ra - start readahead on an extent of a file | |
501 | * @gl: the glock the blocks belong to | |
502 | * @dblock: the starting disk block | |
503 | * @extlen: the number of blocks in the extent | |
504 | * | |
7276b3b0 | 505 | * returns: the first buffer in the extent |
b3b94faa DT |
506 | */ |
507 | ||
7276b3b0 | 508 | struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen) |
b3b94faa | 509 | { |
15562c43 | 510 | struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
b3b94faa | 511 | struct buffer_head *first_bh, *bh; |
cd915493 | 512 | u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >> |
568f4c96 | 513 | sdp->sd_sb.sb_bsize_shift; |
b3b94faa | 514 | |
7276b3b0 SW |
515 | BUG_ON(!extlen); |
516 | ||
517 | if (max_ra < 1) | |
518 | max_ra = 1; | |
b3b94faa DT |
519 | if (extlen > max_ra) |
520 | extlen = max_ra; | |
521 | ||
6802e340 | 522 | first_bh = gfs2_getbuf(gl, dblock, CREATE); |
b3b94faa DT |
523 | |
524 | if (buffer_uptodate(first_bh)) | |
525 | goto out; | |
86a020cc | 526 | bh_read_nowait(first_bh, REQ_META | REQ_PRIO); |
b3b94faa DT |
527 | |
528 | dblock++; | |
529 | extlen--; | |
530 | ||
531 | while (extlen) { | |
6802e340 | 532 | bh = gfs2_getbuf(gl, dblock, CREATE); |
b3b94faa | 533 | |
86a020cc | 534 | bh_readahead(bh, REQ_RAHEAD | REQ_META | REQ_PRIO); |
7276b3b0 | 535 | brelse(bh); |
b3b94faa DT |
536 | dblock++; |
537 | extlen--; | |
7276b3b0 SW |
538 | if (!buffer_locked(first_bh) && buffer_uptodate(first_bh)) |
539 | goto out; | |
b3b94faa DT |
540 | } |
541 | ||
7276b3b0 | 542 | wait_on_buffer(first_bh); |
a91ea69f | 543 | out: |
7276b3b0 | 544 | return first_bh; |
b3b94faa DT |
545 | } |
546 |