2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
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.
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>
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>
34 #include "ops_address.h"
36 static int aspace_get_block(struct inode *inode, sector_t lblock,
37 struct buffer_head *bh_result, int create)
39 gfs2_assert_warn(inode->i_sb->s_fs_info, 0);
43 static int gfs2_aspace_writepage(struct page *page,
44 struct writeback_control *wbc)
46 return block_write_full_page(page, aspace_get_block, wbc);
49 static const struct address_space_operations aspace_aops = {
50 .writepage = gfs2_aspace_writepage,
51 .releasepage = gfs2_releasepage,
52 .sync_page = block_sync_page,
56 * gfs2_aspace_get - Create and initialize a struct inode structure
57 * @sdp: the filesystem the aspace is in
59 * Right now a struct inode is just a struct inode. Maybe Linux
60 * will supply a more lightweight address space construct (that works)
63 * Make sure pages/buffers in this aspace aren't in high memory.
68 struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp)
71 struct gfs2_inode *ip;
73 aspace = new_inode(sdp->sd_vfs);
75 mapping_set_gfp_mask(aspace->i_mapping, GFP_NOFS);
76 aspace->i_mapping->a_ops = &aspace_aops;
77 aspace->i_size = ~0ULL;
79 clear_bit(GIF_USER, &ip->i_flags);
80 insert_inode_hash(aspace);
85 void gfs2_aspace_put(struct inode *aspace)
87 remove_inode_hash(aspace);
92 * gfs2_meta_inval - Invalidate all buffers associated with a glock
97 void gfs2_meta_inval(struct gfs2_glock *gl)
99 struct gfs2_sbd *sdp = gl->gl_sbd;
100 struct inode *aspace = gl->gl_aspace;
101 struct address_space *mapping = gl->gl_aspace->i_mapping;
103 gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
105 atomic_inc(&aspace->i_writecount);
106 truncate_inode_pages(mapping, 0);
107 atomic_dec(&aspace->i_writecount);
109 gfs2_assert_withdraw(sdp, !mapping->nrpages);
113 * gfs2_meta_sync - Sync all buffers associated with a glock
118 void gfs2_meta_sync(struct gfs2_glock *gl)
120 struct address_space *mapping = gl->gl_aspace->i_mapping;
123 filemap_fdatawrite(mapping);
124 error = filemap_fdatawait(mapping);
127 gfs2_io_error(gl->gl_sbd);
131 * gfs2_getbuf - Get a buffer with a given address space
133 * @blkno: the block number (filesystem scope)
134 * @create: 1 if the buffer should be created
136 * Returns: the buffer
139 struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create)
141 struct address_space *mapping = gl->gl_aspace->i_mapping;
142 struct gfs2_sbd *sdp = gl->gl_sbd;
144 struct buffer_head *bh;
149 shift = PAGE_CACHE_SHIFT - sdp->sd_sb.sb_bsize_shift;
150 index = blkno >> shift; /* convert block to page */
151 bufnum = blkno - (index << shift); /* block buf index within page */
155 page = grab_cache_page(mapping, index);
161 page = find_lock_page(mapping, index);
166 if (!page_has_buffers(page))
167 create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0);
169 /* Locate header for our buffer within our page */
170 for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page)
174 if (!buffer_mapped(bh))
175 map_bh(bh, sdp->sd_vfs, blkno);
178 mark_page_accessed(page);
179 page_cache_release(page);
184 static void meta_prep_new(struct buffer_head *bh)
186 struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data;
189 clear_buffer_dirty(bh);
190 set_buffer_uptodate(bh);
193 mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
197 * gfs2_meta_new - Get a block
198 * @gl: The glock associated with this block
199 * @blkno: The block number
201 * Returns: The buffer
204 struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
206 struct buffer_head *bh;
207 bh = gfs2_getbuf(gl, blkno, CREATE);
213 * gfs2_meta_read - Read a block from disk
214 * @gl: The glock covering the block
215 * @blkno: The block number
217 * @bhp: the place where the buffer is returned (NULL on failure)
222 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
223 struct buffer_head **bhp)
225 *bhp = gfs2_getbuf(gl, blkno, CREATE);
226 if (!buffer_uptodate(*bhp)) {
227 ll_rw_block(READ_META, 1, bhp);
228 if (flags & DIO_WAIT) {
229 int error = gfs2_meta_wait(gl->gl_sbd, *bhp);
241 * gfs2_meta_wait - Reread a block from disk
242 * @sdp: the filesystem
243 * @bh: The block to wait for
248 int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh)
250 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
255 if (!buffer_uptodate(bh)) {
256 struct gfs2_trans *tr = current->journal_info;
257 if (tr && tr->tr_touched)
258 gfs2_io_error_bh(sdp, bh);
261 if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
268 * gfs2_attach_bufdata - attach a struct gfs2_bufdata structure to a buffer
269 * @gl: the glock the buffer belongs to
270 * @bh: The buffer to be attached to
271 * @meta: Flag to indicate whether its metadata or not
274 void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
277 struct gfs2_bufdata *bd;
280 lock_page(bh->b_page);
284 unlock_page(bh->b_page);
288 bd = kmem_cache_zalloc(gfs2_bufdata_cachep, GFP_NOFS | __GFP_NOFAIL);
292 INIT_LIST_HEAD(&bd->bd_list_tr);
294 lops_init_le(&bd->bd_le, &gfs2_buf_lops);
296 lops_init_le(&bd->bd_le, &gfs2_databuf_lops);
300 unlock_page(bh->b_page);
303 void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr, int meta)
305 struct gfs2_sbd *sdp = GFS2_SB(bh->b_page->mapping->host);
306 struct gfs2_bufdata *bd = bh->b_private;
307 if (test_clear_buffer_pinned(bh)) {
308 list_del_init(&bd->bd_le.le_list);
310 gfs2_assert_warn(sdp, sdp->sd_log_num_buf);
311 sdp->sd_log_num_buf--;
314 gfs2_assert_warn(sdp, sdp->sd_log_num_databuf);
315 sdp->sd_log_num_databuf--;
316 tr->tr_num_databuf_rm++;
323 gfs2_remove_from_ail(bd);
324 bh->b_private = NULL;
326 bd->bd_blkno = bh->b_blocknr;
327 gfs2_trans_add_revoke(sdp, bd);
330 clear_buffer_dirty(bh);
331 clear_buffer_uptodate(bh);
335 * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore
336 * @ip: the inode who owns the buffers
337 * @bstart: the first buffer in the run
338 * @blen: the number of buffers in the run
342 void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen)
344 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
345 struct buffer_head *bh;
348 bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE);
352 gfs2_remove_from_journal(bh, current->journal_info, 1);
353 gfs2_log_unlock(sdp);
364 * gfs2_meta_indirect_buffer - Get a metadata buffer
365 * @ip: The GFS2 inode
366 * @height: The level of this buf in the metadata (indir addr) tree (if any)
367 * @num: The block number (device relative) of the buffer
368 * @new: Non-zero if we may create a new buffer
369 * @bhp: the buffer is returned here
374 int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
375 int new, struct buffer_head **bhp)
377 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
378 struct gfs2_glock *gl = ip->i_gl;
379 struct buffer_head *bh;
384 bh = gfs2_meta_new(gl, num);
385 gfs2_trans_add_bh(ip->i_gl, bh, 1);
386 gfs2_metatype_set(bh, GFS2_METATYPE_IN, GFS2_FORMAT_IN);
387 gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
389 u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
390 ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh);
391 if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
401 * gfs2_meta_ra - start readahead on an extent of a file
402 * @gl: the glock the blocks belong to
403 * @dblock: the starting disk block
404 * @extlen: the number of blocks in the extent
406 * returns: the first buffer in the extent
409 struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
411 struct gfs2_sbd *sdp = gl->gl_sbd;
412 struct buffer_head *first_bh, *bh;
413 u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >>
414 sdp->sd_sb.sb_bsize_shift;
423 first_bh = gfs2_getbuf(gl, dblock, CREATE);
425 if (buffer_uptodate(first_bh))
427 if (!buffer_locked(first_bh))
428 ll_rw_block(READ_META, 1, &first_bh);
434 bh = gfs2_getbuf(gl, dblock, CREATE);
436 if (!buffer_uptodate(bh) && !buffer_locked(bh))
437 ll_rw_block(READA, 1, &bh);
441 if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
445 wait_on_buffer(first_bh);