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

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

Version: ~ [ linux-5.10-rc5 ] ~ [ linux-5.9.10 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.79 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.159 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.208 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.245 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.245 ] ~ [ 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 /**
101  * gfs2_getbuf - Get a buffer with a given address space
102  * @gl: the glock
103  * @blkno: the block number (filesystem scope)
104  * @create: 1 if the buffer should be created
105  *
106  * Returns: the buffer
107  */
108 
109 struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
110 {
111         struct address_space *mapping = gfs2_glock2aspace(gl);
112         struct gfs2_sbd *sdp = gl->gl_sbd;
113         struct page *page;
114         struct buffer_head *bh;
115         unsigned int shift;
116         unsigned long index;
117         unsigned int bufnum;
118 
119         shift = PAGE_CACHE_SHIFT - sdp->sd_sb.sb_bsize_shift;
120         index = blkno >> shift;             /* convert block to page */
121         bufnum = blkno - (index << shift);  /* block buf index within page */
122 
123         if (create) {
124                 for (;;) {
125                         page = grab_cache_page(mapping, index);
126                         if (page)
127                                 break;
128                         yield();
129                 }
130         } else {
131                 page = find_get_page_flags(mapping, index,
132                                                 FGP_LOCK|FGP_ACCESSED);
133                 if (!page)
134                         return NULL;
135         }
136 
137         if (!page_has_buffers(page))
138                 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
139 
140         /* Locate header for our buffer within our page */
141         for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
142                 /* Do nothing */;
143         get_bh(bh);
144 
145         if (!buffer_mapped(bh))
146                 map_bh(bh, sdp->sd_vfs, blkno);
147 
148         unlock_page(page);
149         page_cache_release(page);
150 
151         return bh;
152 }
153 
154 static void meta_prep_new(struct buffer_head *bh)
155 {
156         struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
157 
158         lock_buffer(bh);
159         clear_buffer_dirty(bh);
160         set_buffer_uptodate(bh);
161         unlock_buffer(bh);
162 
163         mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
164 }
165 
166 /**
167  * gfs2_meta_new - Get a block
168  * @gl: The glock associated with this block
169  * @blkno: The block number
170  *
171  * Returns: The buffer
172  */
173 
174 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
175 {
176         struct buffer_head *bh;
177         bh = gfs2_getbuf(gl, blkno, CREATE);
178         meta_prep_new(bh);
179         return bh;
180 }
181 
182 /**
183  * gfs2_meta_read - Read a block from disk
184  * @gl: The glock covering the block
185  * @blkno: The block number
186  * @flags: flags
187  * @bhp: the place where the buffer is returned (NULL on failure)
188  *
189  * Returns: errno
190  */
191 
192 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
193                    struct buffer_head **bhp)
194 {
195         struct gfs2_sbd *sdp = gl->gl_sbd;
196         struct buffer_head *bh;
197 
198         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
199                 *bhp = NULL;
200                 return -EIO;
201         }
202 
203         *bhp = bh = gfs2_getbuf(gl, blkno, CREATE);
204 
205         lock_buffer(bh);
206         if (buffer_uptodate(bh)) {
207                 unlock_buffer(bh);
208                 return 0;
209         }
210         bh->b_end_io = end_buffer_read_sync;
211         get_bh(bh);
212         submit_bh(READ_SYNC | REQ_META | REQ_PRIO, bh);
213         if (!(flags & DIO_WAIT))
214                 return 0;
215 
216         wait_on_buffer(bh);
217         if (unlikely(!buffer_uptodate(bh))) {
218                 struct gfs2_trans *tr = current->journal_info;
219                 if (tr && tr->tr_touched)
220                         gfs2_io_error_bh(sdp, bh);
221                 brelse(bh);
222                 *bhp = NULL;
223                 return -EIO;
224         }
225 
226         return 0;
227 }
228 
229 /**
230  * gfs2_meta_wait - Reread a block from disk
231  * @sdp: the filesystem
232  * @bh: The block to wait for
233  *
234  * Returns: errno
235  */
236 
237 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
238 {
239         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
240                 return -EIO;
241 
242         wait_on_buffer(bh);
243 
244         if (!buffer_uptodate(bh)) {
245                 struct gfs2_trans *tr = current->journal_info;
246                 if (tr && tr->tr_touched)
247                         gfs2_io_error_bh(sdp, bh);
248                 return -EIO;
249         }
250         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
251                 return -EIO;
252 
253         return 0;
254 }
255 
256 void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr, int meta)
257 {
258         struct address_space *mapping = bh->b_page->mapping;
259         struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
260         struct gfs2_bufdata *bd = bh->b_private;
261         int was_pinned = 0;
262 
263         if (test_clear_buffer_pinned(bh)) {
264                 trace_gfs2_pin(bd, 0);
265                 atomic_dec(&sdp->sd_log_pinned);
266                 list_del_init(&bd->bd_list);
267                 if (meta) {
268                         gfs2_assert_warn(sdp, sdp->sd_log_num_buf);
269                         sdp->sd_log_num_buf--;
270                         tr->tr_num_buf_rm++;
271                 } else {
272                         gfs2_assert_warn(sdp, sdp->sd_log_num_databuf);
273                         sdp->sd_log_num_databuf--;
274                         tr->tr_num_databuf_rm++;
275                 }
276                 tr->tr_touched = 1;
277                 was_pinned = 1;
278                 brelse(bh);
279         }
280         if (bd) {
281                 spin_lock(&sdp->sd_ail_lock);
282                 if (bd->bd_tr) {
283                         gfs2_trans_add_revoke(sdp, bd);
284                 } else if (was_pinned) {
285                         bh->b_private = NULL;
286                         kmem_cache_free(gfs2_bufdata_cachep, bd);
287                 }
288                 spin_unlock(&sdp->sd_ail_lock);
289         }
290         clear_buffer_dirty(bh);
291         clear_buffer_uptodate(bh);
292 }
293 
294 /**
295  * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore
296  * @ip: the inode who owns the buffers
297  * @bstart: the first buffer in the run
298  * @blen: the number of buffers in the run
299  *
300  */
301 
302 void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
303 {
304         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
305         struct buffer_head *bh;
306 
307         while (blen) {
308                 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
309                 if (bh) {
310                         lock_buffer(bh);
311                         gfs2_log_lock(sdp);
312                         gfs2_remove_from_journal(bh, current->journal_info, 1);
313                         gfs2_log_unlock(sdp);
314                         unlock_buffer(bh);
315                         brelse(bh);
316                 }
317 
318                 bstart++;
319                 blen--;
320         }
321 }
322 
323 /**
324  * gfs2_meta_indirect_buffer - Get a metadata buffer
325  * @ip: The GFS2 inode
326  * @height: The level of this buf in the metadata (indir addr) tree (if any)
327  * @num: The block number (device relative) of the buffer
328  * @bhp: the buffer is returned here
329  *
330  * Returns: errno
331  */
332 
333 int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
334                               struct buffer_head **bhp)
335 {
336         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
337         struct gfs2_glock *gl = ip->i_gl;
338         struct buffer_head *bh;
339         int ret = 0;
340         u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
341 
342         ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh);
343         if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
344                 brelse(bh);
345                 ret = -EIO;
346         }
347         *bhp = bh;
348         return ret;
349 }
350 
351 /**
352  * gfs2_meta_ra - start readahead on an extent of a file
353  * @gl: the glock the blocks belong to
354  * @dblock: the starting disk block
355  * @extlen: the number of blocks in the extent
356  *
357  * returns: the first buffer in the extent
358  */
359 
360 struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
361 {
362         struct gfs2_sbd *sdp = gl->gl_sbd;
363         struct buffer_head *first_bh, *bh;
364         u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
365                           sdp->sd_sb.sb_bsize_shift;
366 
367         BUG_ON(!extlen);
368 
369         if (max_ra < 1)
370                 max_ra = 1;
371         if (extlen > max_ra)
372                 extlen = max_ra;
373 
374         first_bh = gfs2_getbuf(gl, dblock, CREATE);
375 
376         if (buffer_uptodate(first_bh))
377                 goto out;
378         if (!buffer_locked(first_bh))
379                 ll_rw_block(READ_SYNC | REQ_META, 1, &first_bh);
380 
381         dblock++;
382         extlen--;
383 
384         while (extlen) {
385                 bh = gfs2_getbuf(gl, dblock, CREATE);
386 
387                 if (!buffer_uptodate(bh) && !buffer_locked(bh))
388                         ll_rw_block(READA | REQ_META, 1, &bh);
389                 brelse(bh);
390                 dblock++;
391                 extlen--;
392                 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
393                         goto out;
394         }
395 
396         wait_on_buffer(first_bh);
397 out:
398         return first_bh;
399 }
400 
401 

~ [ 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