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 33 static 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 91 const 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 98 const 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 */ 113 114 struct 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 folio *folio; 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 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) 137 bh = create_empty_buffers(folio, 138 sdp->sd_sb.sb_bsize, 0); 139 } else { 140 folio = __filemap_get_folio(mapping, index, 141 FGP_LOCK | FGP_ACCESSED, 0); 142 if (IS_ERR(folio)) 143 return NULL; 144 bh = folio_buffers(folio); 145 } 146 147 if (!bh) 148 goto out_unlock; 149 150 bh = get_nth_bh(bh, bufnum); 151 if (!buffer_mapped(bh)) 152 map_bh(bh, sdp->sd_vfs, blkno); 153 154 out_unlock: 155 folio_unlock(folio); 156 folio_put(folio); 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 */ 180 181 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno) 182 { 183 struct buffer_head *bh; 184 bh = gfs2_getbuf(gl, blkno, CREATE); 185 meta_prep_new(bh); 186 return bh; 187 } 188 189 static void gfs2_meta_read_endio(struct bio *bio) 190 { 191 struct bio_vec *bvec; 192 struct bvec_iter_all iter_all; 193 194 bio_for_each_segment_all(bvec, bio, iter_all) { 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; 204 bh->b_end_io(bh, !bio->bi_status); 205 bh = next; 206 } while (bh && len); 207 } 208 bio_put(bio); 209 } 210 211 /* 212 * Submit several consecutive buffer head I/O requests as a single bio I/O 213 * request. (See submit_bh_wbc.) 214 */ 215 static void gfs2_submit_bhs(blk_opf_t opf, struct buffer_head *bhs[], int num) 216 { 217 while (num > 0) { 218 struct buffer_head *bh = *bhs; 219 struct bio *bio; 220 221 bio = bio_alloc(bh->b_bdev, num, opf, GFP_NOIO); 222 bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); 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; 233 submit_bio(bio); 234 } 235 } 236 237 /** 238 * gfs2_meta_read - Read a block from disk 239 * @gl: The glock covering the block 240 * @blkno: The block number 241 * @flags: flags 242 * @rahead: Do read-ahead 243 * @bhp: the place where the buffer is returned (NULL on failure) 244 * 245 * Returns: errno 246 */ 247 248 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags, 249 int rahead, struct buffer_head **bhp) 250 { 251 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; 252 struct buffer_head *bh, *bhs[2]; 253 int num = 0; 254 255 if (gfs2_withdrawing_or_withdrawn(sdp) && 256 !gfs2_withdraw_in_prog(sdp)) { 257 *bhp = NULL; 258 return -EIO; 259 } 260 261 *bhp = bh = gfs2_getbuf(gl, blkno, CREATE); 262 263 lock_buffer(bh); 264 if (buffer_uptodate(bh)) { 265 unlock_buffer(bh); 266 flags &= ~DIO_WAIT; 267 } else { 268 bh->b_end_io = end_buffer_read_sync; 269 get_bh(bh); 270 bhs[num++] = bh; 271 } 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 } 285 286 gfs2_submit_bhs(REQ_OP_READ | REQ_META | REQ_PRIO, bhs, num); 287 if (!(flags & DIO_WAIT)) 288 return 0; 289 290 bh = *bhp; 291 wait_on_buffer(bh); 292 if (unlikely(!buffer_uptodate(bh))) { 293 struct gfs2_trans *tr = current->journal_info; 294 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags)) 295 gfs2_io_error_bh_wd(sdp, bh); 296 brelse(bh); 297 *bhp = NULL; 298 return -EIO; 299 } 300 301 return 0; 302 } 303 304 /** 305 * gfs2_meta_wait - Reread a block from disk 306 * @sdp: the filesystem 307 * @bh: The block to wait for 308 * 309 * Returns: errno 310 */ 311 312 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh) 313 { 314 if (gfs2_withdrawing_or_withdrawn(sdp) && 315 !gfs2_withdraw_in_prog(sdp)) 316 return -EIO; 317 318 wait_on_buffer(bh); 319 320 if (!buffer_uptodate(bh)) { 321 struct gfs2_trans *tr = current->journal_info; 322 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags)) 323 gfs2_io_error_bh_wd(sdp, bh); 324 return -EIO; 325 } 326 if (gfs2_withdrawing_or_withdrawn(sdp) && 327 !gfs2_withdraw_in_prog(sdp)) 328 return -EIO; 329 330 return 0; 331 } 332 333 void gfs2_remove_from_journal(struct buffer_head *bh, int meta) 334 { 335 struct address_space *mapping = bh->b_folio->mapping; 336 struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping); 337 struct gfs2_bufdata *bd = bh->b_private; 338 struct gfs2_trans *tr = current->journal_info; 339 int was_pinned = 0; 340 341 if (test_clear_buffer_pinned(bh)) { 342 trace_gfs2_pin(bd, 0); 343 atomic_dec(&sdp->sd_log_pinned); 344 list_del_init(&bd->bd_list); 345 if (meta == REMOVE_META) 346 tr->tr_num_buf_rm++; 347 else 348 tr->tr_num_databuf_rm++; 349 set_bit(TR_TOUCHED, &tr->tr_flags); 350 was_pinned = 1; 351 brelse(bh); 352 } 353 if (bd) { 354 if (bd->bd_tr) { 355 gfs2_trans_add_revoke(sdp, bd); 356 } else if (was_pinned) { 357 bh->b_private = NULL; 358 kmem_cache_free(gfs2_bufdata_cachep, bd); 359 } else if (!list_empty(&bd->bd_ail_st_list) && 360 !list_empty(&bd->bd_ail_gl_list)) { 361 gfs2_remove_from_ail(bd); 362 } 363 } 364 clear_buffer_dirty(bh); 365 clear_buffer_uptodate(bh); 366 } 367 368 /** 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); 406 struct folio *folio; 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); 411 412 folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED, 0); 413 if (IS_ERR(folio)) 414 return NULL; 415 bh = folio_buffers(folio); 416 if (bh) 417 bh = get_nth_bh(bh, bufnum); 418 folio_unlock(folio); 419 folio_put(folio); 420 return bh; 421 } 422 423 /** 424 * gfs2_journal_wipe - make inode's buffers so they aren't dirty/pinned anymore 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 */ 430 431 void gfs2_journal_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen) 432 { 433 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 434 struct buffer_head *bh; 435 int ty; 436 437 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 } 442 443 gfs2_ail1_wipe(sdp, bstart, blen); 444 while (blen) { 445 ty = REMOVE_META; 446 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE); 447 if (!bh && gfs2_is_jdata(ip)) { 448 bh = gfs2_getjdatabuf(ip, bstart); 449 ty = REMOVE_JDATA; 450 } 451 if (bh) { 452 lock_buffer(bh); 453 gfs2_log_lock(sdp); 454 spin_lock(&sdp->sd_ail_lock); 455 gfs2_remove_from_journal(bh, ty); 456 spin_unlock(&sdp->sd_ail_lock); 457 gfs2_log_unlock(sdp); 458 unlock_buffer(bh); 459 brelse(bh); 460 } 461 462 bstart++; 463 blen--; 464 } 465 } 466 467 /** 468 * gfs2_meta_buffer - Get a metadata buffer 469 * @ip: The GFS2 inode 470 * @mtype: The block type (GFS2_METATYPE_*) 471 * @num: The block number (device relative) of the buffer 472 * @bhp: the buffer is returned here 473 * 474 * Returns: errno 475 */ 476 477 int gfs2_meta_buffer(struct gfs2_inode *ip, u32 mtype, u64 num, 478 struct buffer_head **bhp) 479 { 480 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 481 struct gfs2_glock *gl = ip->i_gl; 482 struct buffer_head *bh; 483 int ret = 0; 484 int rahead = 0; 485 486 if (num == ip->i_no_addr) 487 rahead = ip->i_rahead; 488 489 ret = gfs2_meta_read(gl, num, DIO_WAIT, rahead, &bh); 490 if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) { 491 brelse(bh); 492 ret = -EIO; 493 } else { 494 *bhp = bh; 495 } 496 return ret; 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 * 505 * returns: the first buffer in the extent 506 */ 507 508 struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen) 509 { 510 struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; 511 struct buffer_head *first_bh, *bh; 512 u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >> 513 sdp->sd_sb.sb_bsize_shift; 514 515 BUG_ON(!extlen); 516 517 if (max_ra < 1) 518 max_ra = 1; 519 if (extlen > max_ra) 520 extlen = max_ra; 521 522 first_bh = gfs2_getbuf(gl, dblock, CREATE); 523 524 if (buffer_uptodate(first_bh)) 525 goto out; 526 bh_read_nowait(first_bh, REQ_META | REQ_PRIO); 527 528 dblock++; 529 extlen--; 530 531 while (extlen) { 532 bh = gfs2_getbuf(gl, dblock, CREATE); 533 534 bh_readahead(bh, REQ_RAHEAD | REQ_META | REQ_PRIO); 535 brelse(bh); 536 dblock++; 537 extlen--; 538 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh)) 539 goto out; 540 } 541 542 wait_on_buffer(first_bh); 543 out: 544 return first_bh; 545 } 546 547