2 * fs/logfs/segment.c - Handling the Object Store
4 * As should be obvious for Linux kernel code, license is GPLv2
6 * Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
8 * Object store or ostore makes up the complete device with exception of
9 * the superblock and journal areas. Apart from its own metadata it stores
10 * three kinds of objects: inodes, dentries and blocks, both data and indirect.
14 static int logfs_mark_segment_bad(struct super_block *sb, u32 segno)
16 struct logfs_super *super = logfs_super(sb);
17 struct btree_head32 *head = &super->s_reserved_segments;
20 err = btree_insert32(head, segno, (void *)1, GFP_NOFS);
23 logfs_super(sb)->s_bad_segments++;
24 /* FIXME: write to journal */
28 int logfs_erase_segment(struct super_block *sb, u32 segno, int ensure_erase)
30 struct logfs_super *super = logfs_super(sb);
34 return super->s_devops->erase(sb, (u64)segno << super->s_segshift,
35 super->s_segsize, ensure_erase);
38 static s64 logfs_get_free_bytes(struct logfs_area *area, size_t bytes)
42 logfs_open_area(area, bytes);
44 ofs = area->a_used_bytes;
45 area->a_used_bytes += bytes;
46 BUG_ON(area->a_used_bytes >= logfs_super(area->a_sb)->s_segsize);
48 return dev_ofs(area->a_sb, area->a_segno, ofs);
51 static struct page *get_mapping_page(struct super_block *sb, pgoff_t index,
54 struct logfs_super *super = logfs_super(sb);
55 struct address_space *mapping = super->s_mapping_inode->i_mapping;
56 filler_t *filler = super->s_devops->readpage;
59 BUG_ON(mapping_gfp_mask(mapping) & __GFP_FS);
61 page = read_cache_page(mapping, index, filler, sb);
63 page = find_or_create_page(mapping, index, GFP_NOFS);
69 void __logfs_buf_write(struct logfs_area *area, u64 ofs, void *buf, size_t len,
72 pgoff_t index = ofs >> PAGE_SHIFT;
74 long offset = ofs & (PAGE_SIZE-1);
77 /* Only logfs_wbuf_recover may use len==0 */
78 BUG_ON(!len && !use_filler);
80 copylen = min((ulong)len, PAGE_SIZE - offset);
82 page = get_mapping_page(area->a_sb, index, use_filler);
83 SetPageUptodate(page);
84 BUG_ON(!page); /* FIXME: reserve a pool */
85 memcpy(page_address(page) + offset, buf, copylen);
87 page_cache_release(page);
96 static void pad_partial_page(struct logfs_area *area)
98 struct super_block *sb = area->a_sb;
100 u64 ofs = dev_ofs(sb, area->a_segno, area->a_used_bytes);
101 pgoff_t index = ofs >> PAGE_SHIFT;
102 long offset = ofs & (PAGE_SIZE-1);
103 u32 len = PAGE_SIZE - offset;
105 if (len % PAGE_SIZE) {
106 page = get_mapping_page(sb, index, 0);
107 BUG_ON(!page); /* FIXME: reserve a pool */
108 memset(page_address(page) + offset, 0xff, len);
109 SetPagePrivate(page);
110 page_cache_release(page);
114 static void pad_full_pages(struct logfs_area *area)
116 struct super_block *sb = area->a_sb;
117 struct logfs_super *super = logfs_super(sb);
118 u64 ofs = dev_ofs(sb, area->a_segno, area->a_used_bytes);
119 u32 len = super->s_segsize - area->a_used_bytes;
120 pgoff_t index = PAGE_CACHE_ALIGN(ofs) >> PAGE_CACHE_SHIFT;
121 pgoff_t no_indizes = len >> PAGE_CACHE_SHIFT;
125 page = get_mapping_page(sb, index, 0);
126 BUG_ON(!page); /* FIXME: reserve a pool */
127 SetPageUptodate(page);
128 memset(page_address(page), 0xff, PAGE_CACHE_SIZE);
129 SetPagePrivate(page);
130 page_cache_release(page);
137 * bdev_writeseg will write full pages. Memset the tail to prevent data leaks.
138 * Also make sure we allocate (and memset) all pages for final writeout.
140 static void pad_wbuf(struct logfs_area *area, int final)
142 pad_partial_page(area);
144 pad_full_pages(area);
148 * We have to be careful with the alias tree. Since lookup is done by bix,
149 * it needs to be normalized, so 14, 15, 16, etc. all match when dealing with
150 * indirect blocks. So always use it through accessor functions.
152 static void *alias_tree_lookup(struct super_block *sb, u64 ino, u64 bix,
155 struct btree_head128 *head = &logfs_super(sb)->s_object_alias_tree;
156 pgoff_t index = logfs_pack_index(bix, level);
158 return btree_lookup128(head, ino, index);
161 static int alias_tree_insert(struct super_block *sb, u64 ino, u64 bix,
162 level_t level, void *val)
164 struct btree_head128 *head = &logfs_super(sb)->s_object_alias_tree;
165 pgoff_t index = logfs_pack_index(bix, level);
167 return btree_insert128(head, ino, index, val, GFP_NOFS);
170 static int btree_write_alias(struct super_block *sb, struct logfs_block *block,
171 write_alias_t *write_one_alias)
173 struct object_alias_item *item;
176 list_for_each_entry(item, &block->item_list, list) {
177 err = write_alias_journal(sb, block->ino, block->bix,
178 block->level, item->child_no, item->val);
185 static gc_level_t btree_block_level(struct logfs_block *block)
187 return expand_level(block->ino, block->level);
190 static struct logfs_block_ops btree_block_ops = {
191 .write_block = btree_write_block,
192 .block_level = btree_block_level,
193 .free_block = __free_block,
194 .write_alias = btree_write_alias,
197 int logfs_load_object_aliases(struct super_block *sb,
198 struct logfs_obj_alias *oa, int count)
200 struct logfs_super *super = logfs_super(sb);
201 struct logfs_block *block;
202 struct object_alias_item *item;
207 super->s_flags |= LOGFS_SB_FLAG_OBJ_ALIAS;
208 count /= sizeof(*oa);
209 for (i = 0; i < count; i++) {
210 item = mempool_alloc(super->s_alias_pool, GFP_NOFS);
213 memset(item, 0, sizeof(*item));
215 super->s_no_object_aliases++;
216 item->val = oa[i].val;
217 item->child_no = be16_to_cpu(oa[i].child_no);
219 ino = be64_to_cpu(oa[i].ino);
220 bix = be64_to_cpu(oa[i].bix);
221 level = LEVEL(oa[i].level);
223 log_aliases("logfs_load_object_aliases(%llx, %llx, %x, %x) %llx\n",
224 ino, bix, level, item->child_no,
225 be64_to_cpu(item->val));
226 block = alias_tree_lookup(sb, ino, bix, level);
228 block = __alloc_block(sb, ino, bix, level);
229 block->ops = &btree_block_ops;
230 err = alias_tree_insert(sb, ino, bix, level, block);
231 BUG_ON(err); /* mempool empty */
233 if (test_and_set_bit(item->child_no, block->alias_map)) {
234 printk(KERN_ERR"LogFS: Alias collision detected\n");
237 list_move_tail(&block->alias_list, &super->s_object_alias);
238 list_add(&item->list, &block->item_list);
243 static void kill_alias(void *_block, unsigned long ignore0,
244 u64 ignore1, u64 ignore2, size_t ignore3)
246 struct logfs_block *block = _block;
247 struct super_block *sb = block->sb;
248 struct logfs_super *super = logfs_super(sb);
249 struct object_alias_item *item;
251 while (!list_empty(&block->item_list)) {
252 item = list_entry(block->item_list.next, typeof(*item), list);
253 list_del(&item->list);
254 mempool_free(item, super->s_alias_pool);
256 block->ops->free_block(sb, block);
259 static int obj_type(struct inode *inode, level_t level)
262 if (S_ISDIR(inode->i_mode))
264 if (inode->i_ino == LOGFS_INO_MASTER)
270 static int obj_len(struct super_block *sb, int obj_type)
274 return sizeof(struct logfs_disk_dentry);
276 return sizeof(struct logfs_disk_inode);
278 return sb->s_blocksize;
284 static int __logfs_segment_write(struct inode *inode, void *buf,
285 struct logfs_shadow *shadow, int type, int len, int compr)
287 struct logfs_area *area;
288 struct super_block *sb = inode->i_sb;
290 struct logfs_object_header h;
293 if (shadow->gc_level == 0)
296 acc_len = obj_len(sb, type);
298 area = get_area(sb, shadow->gc_level);
299 ofs = logfs_get_free_bytes(area, len + LOGFS_OBJECT_HEADERSIZE);
300 LOGFS_BUG_ON(ofs <= 0, sb);
302 * Order is important. logfs_get_free_bytes(), by modifying the
303 * segment file, may modify the content of the very page we're about
304 * to write now. Which is fine, as long as the calculated crc and
305 * written data still match. So do the modifications _before_
306 * calculating the crc.
309 h.len = cpu_to_be16(len);
312 h.ino = cpu_to_be64(inode->i_ino);
313 h.bix = cpu_to_be64(shadow->bix);
314 h.crc = logfs_crc32(&h, sizeof(h) - 4, 4);
315 h.data_crc = logfs_crc32(buf, len, 0);
317 logfs_buf_write(area, ofs, &h, sizeof(h));
318 logfs_buf_write(area, ofs + LOGFS_OBJECT_HEADERSIZE, buf, len);
320 shadow->new_ofs = ofs;
321 shadow->new_len = acc_len + LOGFS_OBJECT_HEADERSIZE;
326 static s64 logfs_segment_write_compress(struct inode *inode, void *buf,
327 struct logfs_shadow *shadow, int type, int len)
329 struct super_block *sb = inode->i_sb;
330 void *compressor_buf = logfs_super(sb)->s_compressed_je;
334 mutex_lock(&logfs_super(sb)->s_journal_mutex);
335 compr_len = logfs_compress(buf, compressor_buf, len, len);
337 if (compr_len >= 0) {
338 ret = __logfs_segment_write(inode, compressor_buf, shadow,
339 type, compr_len, COMPR_ZLIB);
341 ret = __logfs_segment_write(inode, buf, shadow, type, len,
344 mutex_unlock(&logfs_super(sb)->s_journal_mutex);
349 * logfs_segment_write - write data block to object store
350 * @inode: inode containing data
352 * Returns an errno or zero.
354 int logfs_segment_write(struct inode *inode, struct page *page,
355 struct logfs_shadow *shadow)
357 struct super_block *sb = inode->i_sb;
358 struct logfs_super *super = logfs_super(sb);
359 int do_compress, type, len;
363 super->s_flags |= LOGFS_SB_FLAG_DIRTY;
364 BUG_ON(super->s_flags & LOGFS_SB_FLAG_SHUTDOWN);
365 do_compress = logfs_inode(inode)->li_flags & LOGFS_IF_COMPRESSED;
366 if (shadow->gc_level != 0) {
367 /* temporarily disable compression for indirect blocks */
371 type = obj_type(inode, shrink_level(shadow->gc_level));
372 len = obj_len(sb, type);
375 ret = logfs_segment_write_compress(inode, buf, shadow, type,
378 ret = __logfs_segment_write(inode, buf, shadow, type, len,
382 log_segment("logfs_segment_write(%llx, %llx, %x) %llx->%llx %x->%x\n",
383 shadow->ino, shadow->bix, shadow->gc_level,
384 shadow->old_ofs, shadow->new_ofs,
385 shadow->old_len, shadow->new_len);
386 /* this BUG_ON did catch a locking bug. useful */
387 BUG_ON(!(shadow->new_ofs & (super->s_segsize - 1)));
391 int wbuf_read(struct super_block *sb, u64 ofs, size_t len, void *buf)
393 pgoff_t index = ofs >> PAGE_SHIFT;
395 long offset = ofs & (PAGE_SIZE-1);
399 copylen = min((ulong)len, PAGE_SIZE - offset);
401 page = get_mapping_page(sb, index, 1);
403 return PTR_ERR(page);
404 memcpy(buf, page_address(page) + offset, copylen);
405 page_cache_release(page);
416 * The "position" of indirect blocks is ambiguous. It can be the position
417 * of any data block somewhere behind this indirect block. So we need to
418 * normalize the positions through logfs_block_mask() before comparing.
420 static int check_pos(struct super_block *sb, u64 pos1, u64 pos2, level_t level)
422 return (pos1 & logfs_block_mask(sb, level)) !=
423 (pos2 & logfs_block_mask(sb, level));
427 static int read_seg_header(struct super_block *sb, u64 ofs,
428 struct logfs_segment_header *sh)
433 err = wbuf_read(sb, ofs, sizeof(*sh), sh);
436 crc = logfs_crc32(sh, sizeof(*sh), 4);
437 if (crc != sh->crc) {
438 printk(KERN_ERR"LOGFS: header crc error at %llx: expected %x, "
439 "got %x\n", ofs, be32_to_cpu(sh->crc),
447 static int read_obj_header(struct super_block *sb, u64 ofs,
448 struct logfs_object_header *oh)
453 err = wbuf_read(sb, ofs, sizeof(*oh), oh);
456 crc = logfs_crc32(oh, sizeof(*oh) - 4, 4);
457 if (crc != oh->crc) {
458 printk(KERN_ERR"LOGFS: header crc error at %llx: expected %x, "
459 "got %x\n", ofs, be32_to_cpu(oh->crc),
466 static void move_btree_to_page(struct inode *inode, struct page *page,
469 struct super_block *sb = inode->i_sb;
470 struct logfs_super *super = logfs_super(sb);
471 struct btree_head128 *head = &super->s_object_alias_tree;
472 struct logfs_block *block;
473 struct object_alias_item *item, *next;
475 if (!(super->s_flags & LOGFS_SB_FLAG_OBJ_ALIAS))
478 block = btree_remove128(head, inode->i_ino, page->index);
482 log_blockmove("move_btree_to_page(%llx, %llx, %x)\n",
483 block->ino, block->bix, block->level);
484 list_for_each_entry_safe(item, next, &block->item_list, list) {
485 data[item->child_no] = item->val;
486 list_del(&item->list);
487 mempool_free(item, super->s_alias_pool);
490 SetPagePrivate(page);
491 page->private = (unsigned long)block;
492 block->ops = &indirect_block_ops;
493 initialize_block_counters(page, block, data, 0);
497 * This silences a false, yet annoying gcc warning. I hate it when my editor
498 * jumps into bitops.h each time I recompile this file.
499 * TODO: Complain to gcc folks about this and upgrade compiler.
501 static unsigned long fnb(const unsigned long *addr,
502 unsigned long size, unsigned long offset)
504 return find_next_bit(addr, size, offset);
507 void move_page_to_btree(struct page *page)
509 struct logfs_block *block = logfs_block(page);
510 struct super_block *sb = block->sb;
511 struct logfs_super *super = logfs_super(sb);
512 struct object_alias_item *item;
517 if (super->s_flags & LOGFS_SB_FLAG_SHUTDOWN) {
518 block->ops->free_block(sb, block);
521 log_blockmove("move_page_to_btree(%llx, %llx, %x)\n",
522 block->ino, block->bix, block->level);
523 super->s_flags |= LOGFS_SB_FLAG_OBJ_ALIAS;
525 for (pos = 0; ; pos++) {
526 pos = fnb(block->alias_map, LOGFS_BLOCK_FACTOR, pos);
527 if (pos >= LOGFS_BLOCK_FACTOR)
530 item = mempool_alloc(super->s_alias_pool, GFP_NOFS);
531 BUG_ON(!item); /* mempool empty */
532 memset(item, 0, sizeof(*item));
534 child = kmap_atomic(page, KM_USER0);
535 item->val = child[pos];
536 kunmap_atomic(child, KM_USER0);
537 item->child_no = pos;
538 list_add(&item->list, &block->item_list);
541 ClearPagePrivate(page);
543 block->ops = &btree_block_ops;
544 err = alias_tree_insert(block->sb, block->ino, block->bix, block->level,
546 BUG_ON(err); /* mempool empty */
547 ClearPageUptodate(page);
550 static int __logfs_segment_read(struct inode *inode, void *buf,
551 u64 ofs, u64 bix, level_t level)
553 struct super_block *sb = inode->i_sb;
554 void *compressor_buf = logfs_super(sb)->s_compressed_je;
555 struct logfs_object_header oh;
560 block_len = obj_len(sb, obj_type(inode, level));
561 err = read_obj_header(sb, ofs, &oh);
566 if (be64_to_cpu(oh.ino) != inode->i_ino
567 || check_pos(sb, be64_to_cpu(oh.bix), bix, level)) {
568 printk(KERN_ERR"LOGFS: (ino, bix) don't match at %llx: "
569 "expected (%lx, %llx), got (%llx, %llx)\n",
570 ofs, inode->i_ino, bix,
571 be64_to_cpu(oh.ino), be64_to_cpu(oh.bix));
575 len = be16_to_cpu(oh.len);
579 err = wbuf_read(sb, ofs + LOGFS_OBJECT_HEADERSIZE, len, buf);
582 crc = logfs_crc32(buf, len, 0);
583 if (crc != oh.data_crc) {
584 printk(KERN_ERR"LOGFS: uncompressed data crc error at "
585 "%llx: expected %x, got %x\n", ofs,
586 be32_to_cpu(oh.data_crc),
592 mutex_lock(&logfs_super(sb)->s_journal_mutex);
593 err = wbuf_read(sb, ofs + LOGFS_OBJECT_HEADERSIZE, len,
596 mutex_unlock(&logfs_super(sb)->s_journal_mutex);
599 crc = logfs_crc32(compressor_buf, len, 0);
600 if (crc != oh.data_crc) {
601 printk(KERN_ERR"LOGFS: compressed data crc error at "
602 "%llx: expected %x, got %x\n", ofs,
603 be32_to_cpu(oh.data_crc),
605 mutex_unlock(&logfs_super(sb)->s_journal_mutex);
608 err = logfs_uncompress(compressor_buf, buf, len, block_len);
609 mutex_unlock(&logfs_super(sb)->s_journal_mutex);
611 printk(KERN_ERR"LOGFS: uncompress error at %llx\n", ofs);
624 printk(KERN_ERR"LOGFS: device is read-only now\n");
630 * logfs_segment_read - read data block from object store
631 * @inode: inode containing data
633 * @ofs: physical data offset
635 * @level: block level
637 * Returns 0 on success or a negative errno.
639 int logfs_segment_read(struct inode *inode, struct page *page,
640 u64 ofs, u64 bix, level_t level)
645 if (PageUptodate(page))
648 ofs &= ~LOGFS_FULLY_POPULATED;
651 err = __logfs_segment_read(inode, buf, ofs, bix, level);
653 move_btree_to_page(inode, page, buf);
654 SetPageUptodate(page);
657 log_segment("logfs_segment_read(%lx, %llx, %x) %llx (%d)\n",
658 inode->i_ino, bix, level, ofs, err);
662 int logfs_segment_delete(struct inode *inode, struct logfs_shadow *shadow)
664 struct super_block *sb = inode->i_sb;
665 struct logfs_super *super = logfs_super(sb);
666 struct logfs_object_header h;
670 super->s_flags |= LOGFS_SB_FLAG_DIRTY;
671 BUG_ON(super->s_flags & LOGFS_SB_FLAG_SHUTDOWN);
672 BUG_ON(shadow->old_ofs & LOGFS_FULLY_POPULATED);
673 if (!shadow->old_ofs)
676 log_segment("logfs_segment_delete(%llx, %llx, %x) %llx->%llx %x->%x\n",
677 shadow->ino, shadow->bix, shadow->gc_level,
678 shadow->old_ofs, shadow->new_ofs,
679 shadow->old_len, shadow->new_len);
680 err = read_obj_header(sb, shadow->old_ofs, &h);
681 LOGFS_BUG_ON(err, sb);
682 LOGFS_BUG_ON(be64_to_cpu(h.ino) != inode->i_ino, sb);
683 LOGFS_BUG_ON(check_pos(sb, shadow->bix, be64_to_cpu(h.bix),
684 shrink_level(shadow->gc_level)), sb);
686 if (shadow->gc_level == 0)
687 len = be16_to_cpu(h.len);
689 len = obj_len(sb, h.type);
690 shadow->old_len = len + sizeof(h);
694 static void freeseg(struct super_block *sb, u32 segno)
696 struct logfs_super *super = logfs_super(sb);
697 struct address_space *mapping = super->s_mapping_inode->i_mapping;
701 start = dev_ofs(sb, segno, 0);
702 end = dev_ofs(sb, segno + 1, 0);
703 for (ofs = start; ofs < end; ofs += PAGE_SIZE) {
704 page = find_get_page(mapping, ofs >> PAGE_SHIFT);
707 ClearPagePrivate(page);
708 page_cache_release(page);
712 int logfs_open_area(struct logfs_area *area, size_t bytes)
714 struct super_block *sb = area->a_sb;
715 struct logfs_super *super = logfs_super(sb);
718 if (area->a_is_open && area->a_used_bytes + bytes <= super->s_segsize)
721 if (area->a_is_open) {
722 u64 ofs = dev_ofs(sb, area->a_segno, area->a_written_bytes);
723 u32 len = super->s_segsize - area->a_written_bytes;
725 log_gc("logfs_close_area(%x)\n", area->a_segno);
727 super->s_devops->writeseg(area->a_sb, ofs, len);
728 freeseg(sb, area->a_segno);
732 area->a_used_bytes = 0;
733 area->a_written_bytes = 0;
735 area->a_ops->get_free_segment(area);
736 area->a_ops->get_erase_count(area);
738 log_gc("logfs_open_area(%x, %x)\n", area->a_segno, area->a_level);
739 err = area->a_ops->erase_segment(area);
741 printk(KERN_WARNING "LogFS: Error erasing segment %x\n",
743 logfs_mark_segment_bad(sb, area->a_segno);
750 void logfs_sync_area(struct logfs_area *area)
752 struct super_block *sb = area->a_sb;
753 struct logfs_super *super = logfs_super(sb);
754 u64 ofs = dev_ofs(sb, area->a_segno, area->a_written_bytes);
755 u32 len = (area->a_used_bytes - area->a_written_bytes);
757 if (super->s_writesize)
758 len &= ~(super->s_writesize - 1);
762 super->s_devops->writeseg(sb, ofs, len);
763 area->a_written_bytes += len;
766 void logfs_sync_segments(struct super_block *sb)
768 struct logfs_super *super = logfs_super(sb);
772 logfs_sync_area(super->s_area[i]);
776 * Pick a free segment to be used for this area. Effectively takes a
777 * candidate from the free list (not really a candidate anymore).
779 static void ostore_get_free_segment(struct logfs_area *area)
781 struct super_block *sb = area->a_sb;
782 struct logfs_super *super = logfs_super(sb);
784 if (super->s_free_list.count == 0) {
785 printk(KERN_ERR"LOGFS: ran out of free segments\n");
789 area->a_segno = get_best_cand(sb, &super->s_free_list, NULL);
792 static void ostore_get_erase_count(struct logfs_area *area)
794 struct logfs_segment_entry se;
797 logfs_get_segment_entry(area->a_sb, area->a_segno, &se);
798 BUG_ON(se.ec_level == cpu_to_be32(BADSEG) ||
799 se.valid == cpu_to_be32(RESERVED));
801 ec_level = be32_to_cpu(se.ec_level);
802 area->a_erase_count = (ec_level >> 4) + 1;
805 static int ostore_erase_segment(struct logfs_area *area)
807 struct super_block *sb = area->a_sb;
808 struct logfs_segment_header sh;
812 err = logfs_erase_segment(sb, area->a_segno, 0);
817 sh.type = SEG_OSTORE;
818 sh.level = (__force u8)area->a_level;
819 sh.segno = cpu_to_be32(area->a_segno);
820 sh.ec = cpu_to_be32(area->a_erase_count);
821 sh.gec = cpu_to_be64(logfs_super(sb)->s_gec);
822 sh.crc = logfs_crc32(&sh, sizeof(sh), 4);
824 logfs_set_segment_erased(sb, area->a_segno, area->a_erase_count,
827 ofs = dev_ofs(sb, area->a_segno, 0);
828 area->a_used_bytes = sizeof(sh);
829 logfs_buf_write(area, ofs, &sh, sizeof(sh));
833 static const struct logfs_area_ops ostore_area_ops = {
834 .get_free_segment = ostore_get_free_segment,
835 .get_erase_count = ostore_get_erase_count,
836 .erase_segment = ostore_erase_segment,
839 static void free_area(struct logfs_area *area)
842 freeseg(area->a_sb, area->a_segno);
846 static struct logfs_area *alloc_area(struct super_block *sb)
848 struct logfs_area *area;
850 area = kzalloc(sizeof(*area), GFP_KERNEL);
858 static void map_invalidatepage(struct page *page, unsigned long l)
863 static int map_releasepage(struct page *page, gfp_t g)
865 /* Don't release these pages */
869 static const struct address_space_operations mapping_aops = {
870 .invalidatepage = map_invalidatepage,
871 .releasepage = map_releasepage,
872 .set_page_dirty = __set_page_dirty_nobuffers,
875 int logfs_init_mapping(struct super_block *sb)
877 struct logfs_super *super = logfs_super(sb);
878 struct address_space *mapping;
881 inode = logfs_new_meta_inode(sb, LOGFS_INO_MAPPING);
883 return PTR_ERR(inode);
884 super->s_mapping_inode = inode;
885 mapping = inode->i_mapping;
886 mapping->a_ops = &mapping_aops;
887 /* Would it be possible to use __GFP_HIGHMEM as well? */
888 mapping_set_gfp_mask(mapping, GFP_NOFS);
892 int logfs_init_areas(struct super_block *sb)
894 struct logfs_super *super = logfs_super(sb);
897 super->s_alias_pool = mempool_create_kmalloc_pool(600,
898 sizeof(struct object_alias_item));
899 if (!super->s_alias_pool)
902 super->s_journal_area = alloc_area(sb);
903 if (!super->s_journal_area)
907 super->s_area[i] = alloc_area(sb);
908 if (!super->s_area[i])
910 super->s_area[i]->a_level = GC_LEVEL(i);
911 super->s_area[i]->a_ops = &ostore_area_ops;
913 btree_init_mempool128(&super->s_object_alias_tree,
914 super->s_btree_pool);
918 for (i--; i >= 0; i--)
919 free_area(super->s_area[i]);
920 free_area(super->s_journal_area);
921 mempool_destroy(super->s_alias_pool);
925 void logfs_cleanup_areas(struct super_block *sb)
927 struct logfs_super *super = logfs_super(sb);
930 btree_grim_visitor128(&super->s_object_alias_tree, 0, kill_alias);
932 free_area(super->s_area[i]);
933 free_area(super->s_journal_area);
934 destroy_meta_inode(super->s_mapping_inode);