~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/gfs2/meta_io.c

Version: ~ [ linux-5.11-rc3 ] ~ [ linux-5.10.7 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.89 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.167 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.215 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.251 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.251 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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         int 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         .writepage = gfs2_aspace_writepage,
 93         .releasepage = gfs2_releasepage,
 94 };
 95 
 96 const struct address_space_operations gfs2_rgrp_aops = {
 97         .writepage = gfs2_aspace_writepage,
 98         .releasepage = gfs2_releasepage,
 99 };
100 
101 /**
102  * gfs2_getbuf - Get a buffer with a given address space
103  * @gl: the glock
104  * @blkno: the block number (filesystem scope)
105  * @create: 1 if the buffer should be created
106  *
107  * Returns: the buffer
108  */
109 
110 struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
111 {
112         struct address_space *mapping = gfs2_glock2aspace(gl);
113         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
114         struct page *page;
115         struct buffer_head *bh;
116         unsigned int shift;
117         unsigned long index;
118         unsigned int bufnum;
119 
120         if (mapping == NULL)
121                 mapping = &sdp->sd_aspace;
122 
123         shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift;
124         index = blkno >> shift;             /* convert block to page */
125         bufnum = blkno - (index << shift);  /* block buf index within page */
126 
127         if (create) {
128                 for (;;) {
129                         page = grab_cache_page(mapping, index);
130                         if (page)
131                                 break;
132                         yield();
133                 }
134         } else {
135                 page = find_get_page_flags(mapping, index,
136                                                 FGP_LOCK|FGP_ACCESSED);
137                 if (!page)
138                         return NULL;
139         }
140 
141         if (!page_has_buffers(page))
142                 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
143 
144         /* Locate header for our buffer within our page */
145         for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
146                 /* Do nothing */;
147         get_bh(bh);
148 
149         if (!buffer_mapped(bh))
150                 map_bh(bh, sdp->sd_vfs, blkno);
151 
152         unlock_page(page);
153         put_page(page);
154 
155         return bh;
156 }
157 
158 static void meta_prep_new(struct buffer_head *bh)
159 {
160         struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
161 
162         lock_buffer(bh);
163         clear_buffer_dirty(bh);
164         set_buffer_uptodate(bh);
165         unlock_buffer(bh);
166 
167         mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
168 }
169 
170 /**
171  * gfs2_meta_new - Get a block
172  * @gl: The glock associated with this block
173  * @blkno: The block number
174  *
175  * Returns: The buffer
176  */
177 
178 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
179 {
180         struct buffer_head *bh;
181         bh = gfs2_getbuf(gl, blkno, CREATE);
182         meta_prep_new(bh);
183         return bh;
184 }
185 
186 static void gfs2_meta_read_endio(struct bio *bio)
187 {
188         struct bio_vec *bvec;
189         struct bvec_iter_all iter_all;
190 
191         bio_for_each_segment_all(bvec, bio, iter_all) {
192                 struct page *page = bvec->bv_page;
193                 struct buffer_head *bh = page_buffers(page);
194                 unsigned int len = bvec->bv_len;
195 
196                 while (bh_offset(bh) < bvec->bv_offset)
197                         bh = bh->b_this_page;
198                 do {
199                         struct buffer_head *next = bh->b_this_page;
200                         len -= bh->b_size;
201                         bh->b_end_io(bh, !bio->bi_status);
202                         bh = next;
203                 } while (bh && len);
204         }
205         bio_put(bio);
206 }
207 
208 /*
209  * Submit several consecutive buffer head I/O requests as a single bio I/O
210  * request.  (See submit_bh_wbc.)
211  */
212 static void gfs2_submit_bhs(int op, int op_flags, struct buffer_head *bhs[],
213                             int num)
214 {
215         while (num > 0) {
216                 struct buffer_head *bh = *bhs;
217                 struct bio *bio;
218 
219                 bio = bio_alloc(GFP_NOIO, num);
220                 bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
221                 bio_set_dev(bio, bh->b_bdev);
222                 while (num > 0) {
223                         bh = *bhs;
224                         if (!bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh))) {
225                                 BUG_ON(bio->bi_iter.bi_size == 0);
226                                 break;
227                         }
228                         bhs++;
229                         num--;
230                 }
231                 bio->bi_end_io = gfs2_meta_read_endio;
232                 bio_set_op_attrs(bio, op, op_flags);
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  * @bhp: the place where the buffer is returned (NULL on failure)
243  *
244  * Returns: errno
245  */
246 
247 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
248                    int rahead, struct buffer_head **bhp)
249 {
250         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
251         struct buffer_head *bh, *bhs[2];
252         int num = 0;
253 
254         if (unlikely(gfs2_withdrawn(sdp)) &&
255             (!sdp->sd_jdesc || gl != sdp->sd_jinode_gl)) {
256                 *bhp = NULL;
257                 return -EIO;
258         }
259 
260         *bhp = bh = gfs2_getbuf(gl, blkno, CREATE);
261 
262         lock_buffer(bh);
263         if (buffer_uptodate(bh)) {
264                 unlock_buffer(bh);
265                 flags &= ~DIO_WAIT;
266         } else {
267                 bh->b_end_io = end_buffer_read_sync;
268                 get_bh(bh);
269                 bhs[num++] = bh;
270         }
271 
272         if (rahead) {
273                 bh = gfs2_getbuf(gl, blkno + 1, CREATE);
274 
275                 lock_buffer(bh);
276                 if (buffer_uptodate(bh)) {
277                         unlock_buffer(bh);
278                         brelse(bh);
279                 } else {
280                         bh->b_end_io = end_buffer_read_sync;
281                         bhs[num++] = bh;
282                 }
283         }
284 
285         gfs2_submit_bhs(REQ_OP_READ, REQ_META | REQ_PRIO, bhs, num);
286         if (!(flags & DIO_WAIT))
287                 return 0;
288 
289         bh = *bhp;
290         wait_on_buffer(bh);
291         if (unlikely(!buffer_uptodate(bh))) {
292                 struct gfs2_trans *tr = current->journal_info;
293                 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags))
294                         gfs2_io_error_bh_wd(sdp, bh);
295                 brelse(bh);
296                 *bhp = NULL;
297                 return -EIO;
298         }
299 
300         return 0;
301 }
302 
303 /**
304  * gfs2_meta_wait - Reread a block from disk
305  * @sdp: the filesystem
306  * @bh: The block to wait for
307  *
308  * Returns: errno
309  */
310 
311 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
312 {
313         if (unlikely(gfs2_withdrawn(sdp)))
314                 return -EIO;
315 
316         wait_on_buffer(bh);
317 
318         if (!buffer_uptodate(bh)) {
319                 struct gfs2_trans *tr = current->journal_info;
320                 if (tr && test_bit(TR_TOUCHED, &tr->tr_flags))
321                         gfs2_io_error_bh_wd(sdp, bh);
322                 return -EIO;
323         }
324         if (unlikely(gfs2_withdrawn(sdp)))
325                 return -EIO;
326 
327         return 0;
328 }
329 
330 void gfs2_remove_from_journal(struct buffer_head *bh, int meta)
331 {
332         struct address_space *mapping = bh->b_page->mapping;
333         struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
334         struct gfs2_bufdata *bd = bh->b_private;
335         struct gfs2_trans *tr = current->journal_info;
336         int was_pinned = 0;
337 
338         if (test_clear_buffer_pinned(bh)) {
339                 trace_gfs2_pin(bd, 0);
340                 atomic_dec(&sdp->sd_log_pinned);
341                 list_del_init(&bd->bd_list);
342                 if (meta == REMOVE_META)
343                         tr->tr_num_buf_rm++;
344                 else
345                         tr->tr_num_databuf_rm++;
346                 set_bit(TR_TOUCHED, &tr->tr_flags);
347                 was_pinned = 1;
348                 brelse(bh);
349         }
350         if (bd) {
351                 spin_lock(&sdp->sd_ail_lock);
352                 if (bd->bd_tr) {
353                         gfs2_trans_add_revoke(sdp, bd);
354                 } else if (was_pinned) {
355                         bh->b_private = NULL;
356                         kmem_cache_free(gfs2_bufdata_cachep, bd);
357                 }
358                 spin_unlock(&sdp->sd_ail_lock);
359         }
360         clear_buffer_dirty(bh);
361         clear_buffer_uptodate(bh);
362 }
363 
364 /**
365  * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore
366  * @ip: the inode who owns the buffers
367  * @bstart: the first buffer in the run
368  * @blen: the number of buffers in the run
369  *
370  */
371 
372 void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
373 {
374         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
375         struct buffer_head *bh;
376 
377         while (blen) {
378                 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
379                 if (bh) {
380                         lock_buffer(bh);
381                         gfs2_log_lock(sdp);
382                         gfs2_remove_from_journal(bh, REMOVE_META);
383                         gfs2_log_unlock(sdp);
384                         unlock_buffer(bh);
385                         brelse(bh);
386                 }
387 
388                 bstart++;
389                 blen--;
390         }
391 }
392 
393 /**
394  * gfs2_meta_indirect_buffer - Get a metadata buffer
395  * @ip: The GFS2 inode
396  * @height: The level of this buf in the metadata (indir addr) tree (if any)
397  * @num: The block number (device relative) of the buffer
398  * @bhp: the buffer is returned here
399  *
400  * Returns: errno
401  */
402 
403 int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
404                               struct buffer_head **bhp)
405 {
406         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
407         struct gfs2_glock *gl = ip->i_gl;
408         struct buffer_head *bh;
409         int ret = 0;
410         u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
411         int rahead = 0;
412 
413         if (num == ip->i_no_addr)
414                 rahead = ip->i_rahead;
415 
416         ret = gfs2_meta_read(gl, num, DIO_WAIT, rahead, &bh);
417         if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
418                 brelse(bh);
419                 ret = -EIO;
420         } else {
421                 *bhp = bh;
422         }
423         return ret;
424 }
425 
426 /**
427  * gfs2_meta_ra - start readahead on an extent of a file
428  * @gl: the glock the blocks belong to
429  * @dblock: the starting disk block
430  * @extlen: the number of blocks in the extent
431  *
432  * returns: the first buffer in the extent
433  */
434 
435 struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
436 {
437         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
438         struct buffer_head *first_bh, *bh;
439         u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
440                           sdp->sd_sb.sb_bsize_shift;
441 
442         BUG_ON(!extlen);
443 
444         if (max_ra < 1)
445                 max_ra = 1;
446         if (extlen > max_ra)
447                 extlen = max_ra;
448 
449         first_bh = gfs2_getbuf(gl, dblock, CREATE);
450 
451         if (buffer_uptodate(first_bh))
452                 goto out;
453         if (!buffer_locked(first_bh))
454                 ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &first_bh);
455 
456         dblock++;
457         extlen--;
458 
459         while (extlen) {
460                 bh = gfs2_getbuf(gl, dblock, CREATE);
461 
462                 if (!buffer_uptodate(bh) && !buffer_locked(bh))
463                         ll_rw_block(REQ_OP_READ,
464                                     REQ_RAHEAD | REQ_META | REQ_PRIO,
465                                     1, &bh);
466                 brelse(bh);
467                 dblock++;
468                 extlen--;
469                 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
470                         goto out;
471         }
472 
473         wait_on_buffer(first_bh);
474 out:
475         return first_bh;
476 }
477 
478 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp