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

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

Version: ~ [ linux-5.10-rc6 ] ~ [ linux-5.9.12 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.81 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.161 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.210 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.247 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.247 ] ~ [ 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 /*
  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 
 36 static 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 flusher thread 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 
 95 const struct address_space_operations gfs2_meta_aops = {
 96         .writepage = gfs2_aspace_writepage,
 97         .releasepage = gfs2_releasepage,
 98 };
 99 
100 const struct address_space_operations gfs2_rgrp_aops = {
101         .writepage = gfs2_aspace_writepage,
102         .releasepage = gfs2_releasepage,
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 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_CACHE_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         } else {
139                 page = find_get_page_flags(mapping, index,
140                                                 FGP_LOCK|FGP_ACCESSED);
141                 if (!page)
142                         return NULL;
143         }
144 
145         if (!page_has_buffers(page))
146                 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
147 
148         /* Locate header for our buffer within our page */
149         for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
150                 /* Do nothing */;
151         get_bh(bh);
152 
153         if (!buffer_mapped(bh))
154                 map_bh(bh, sdp->sd_vfs, blkno);
155 
156         unlock_page(page);
157         page_cache_release(page);
158 
159         return bh;
160 }
161 
162 static void meta_prep_new(struct buffer_head *bh)
163 {
164         struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
165 
166         lock_buffer(bh);
167         clear_buffer_dirty(bh);
168         set_buffer_uptodate(bh);
169         unlock_buffer(bh);
170 
171         mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
172 }
173 
174 /**
175  * gfs2_meta_new - Get a block
176  * @gl: The glock associated with this block
177  * @blkno: The block number
178  *
179  * Returns: The buffer
180  */
181 
182 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
183 {
184         struct buffer_head *bh;
185         bh = gfs2_getbuf(gl, blkno, CREATE);
186         meta_prep_new(bh);
187         return bh;
188 }
189 
190 /**
191  * gfs2_meta_read - Read a block from disk
192  * @gl: The glock covering the block
193  * @blkno: The block number
194  * @flags: flags
195  * @bhp: the place where the buffer is returned (NULL on failure)
196  *
197  * Returns: errno
198  */
199 
200 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
201                    struct buffer_head **bhp)
202 {
203         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
204         struct buffer_head *bh;
205 
206         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
207                 *bhp = NULL;
208                 return -EIO;
209         }
210 
211         *bhp = bh = gfs2_getbuf(gl, blkno, CREATE);
212 
213         lock_buffer(bh);
214         if (buffer_uptodate(bh)) {
215                 unlock_buffer(bh);
216                 return 0;
217         }
218         bh->b_end_io = end_buffer_read_sync;
219         get_bh(bh);
220         submit_bh(READ_SYNC | REQ_META | REQ_PRIO, bh);
221         if (!(flags & DIO_WAIT))
222                 return 0;
223 
224         wait_on_buffer(bh);
225         if (unlikely(!buffer_uptodate(bh))) {
226                 struct gfs2_trans *tr = current->journal_info;
227                 if (tr && tr->tr_touched)
228                         gfs2_io_error_bh(sdp, bh);
229                 brelse(bh);
230                 *bhp = NULL;
231                 return -EIO;
232         }
233 
234         return 0;
235 }
236 
237 /**
238  * gfs2_meta_wait - Reread a block from disk
239  * @sdp: the filesystem
240  * @bh: The block to wait for
241  *
242  * Returns: errno
243  */
244 
245 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
246 {
247         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
248                 return -EIO;
249 
250         wait_on_buffer(bh);
251 
252         if (!buffer_uptodate(bh)) {
253                 struct gfs2_trans *tr = current->journal_info;
254                 if (tr && tr->tr_touched)
255                         gfs2_io_error_bh(sdp, bh);
256                 return -EIO;
257         }
258         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
259                 return -EIO;
260 
261         return 0;
262 }
263 
264 void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr, int meta)
265 {
266         struct address_space *mapping = bh->b_page->mapping;
267         struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
268         struct gfs2_bufdata *bd = bh->b_private;
269         int was_pinned = 0;
270 
271         if (test_clear_buffer_pinned(bh)) {
272                 trace_gfs2_pin(bd, 0);
273                 atomic_dec(&sdp->sd_log_pinned);
274                 list_del_init(&bd->bd_list);
275                 if (meta)
276                         tr->tr_num_buf_rm++;
277                 else
278                         tr->tr_num_databuf_rm++;
279                 tr->tr_touched = 1;
280                 was_pinned = 1;
281                 brelse(bh);
282         }
283         if (bd) {
284                 spin_lock(&sdp->sd_ail_lock);
285                 if (bd->bd_tr) {
286                         gfs2_trans_add_revoke(sdp, bd);
287                 } else if (was_pinned) {
288                         bh->b_private = NULL;
289                         kmem_cache_free(gfs2_bufdata_cachep, bd);
290                 }
291                 spin_unlock(&sdp->sd_ail_lock);
292         }
293         clear_buffer_dirty(bh);
294         clear_buffer_uptodate(bh);
295 }
296 
297 /**
298  * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore
299  * @ip: the inode who owns the buffers
300  * @bstart: the first buffer in the run
301  * @blen: the number of buffers in the run
302  *
303  */
304 
305 void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
306 {
307         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
308         struct buffer_head *bh;
309 
310         while (blen) {
311                 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
312                 if (bh) {
313                         lock_buffer(bh);
314                         gfs2_log_lock(sdp);
315                         gfs2_remove_from_journal(bh, current->journal_info, 1);
316                         gfs2_log_unlock(sdp);
317                         unlock_buffer(bh);
318                         brelse(bh);
319                 }
320 
321                 bstart++;
322                 blen--;
323         }
324 }
325 
326 /**
327  * gfs2_meta_indirect_buffer - Get a metadata buffer
328  * @ip: The GFS2 inode
329  * @height: The level of this buf in the metadata (indir addr) tree (if any)
330  * @num: The block number (device relative) of the buffer
331  * @bhp: the buffer is returned here
332  *
333  * Returns: errno
334  */
335 
336 int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
337                               struct buffer_head **bhp)
338 {
339         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
340         struct gfs2_glock *gl = ip->i_gl;
341         struct buffer_head *bh;
342         int ret = 0;
343         u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
344 
345         ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh);
346         if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
347                 brelse(bh);
348                 ret = -EIO;
349         }
350         *bhp = bh;
351         return ret;
352 }
353 
354 /**
355  * gfs2_meta_ra - start readahead on an extent of a file
356  * @gl: the glock the blocks belong to
357  * @dblock: the starting disk block
358  * @extlen: the number of blocks in the extent
359  *
360  * returns: the first buffer in the extent
361  */
362 
363 struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
364 {
365         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
366         struct buffer_head *first_bh, *bh;
367         u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
368                           sdp->sd_sb.sb_bsize_shift;
369 
370         BUG_ON(!extlen);
371 
372         if (max_ra < 1)
373                 max_ra = 1;
374         if (extlen > max_ra)
375                 extlen = max_ra;
376 
377         first_bh = gfs2_getbuf(gl, dblock, CREATE);
378 
379         if (buffer_uptodate(first_bh))
380                 goto out;
381         if (!buffer_locked(first_bh))
382                 ll_rw_block(READ_SYNC | REQ_META, 1, &first_bh);
383 
384         dblock++;
385         extlen--;
386 
387         while (extlen) {
388                 bh = gfs2_getbuf(gl, dblock, CREATE);
389 
390                 if (!buffer_uptodate(bh) && !buffer_locked(bh))
391                         ll_rw_block(READA | REQ_META, 1, &bh);
392                 brelse(bh);
393                 dblock++;
394                 extlen--;
395                 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
396                         goto out;
397         }
398 
399         wait_on_buffer(first_bh);
400 out:
401         return first_bh;
402 }
403 
404 

~ [ 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