}
/*
- * lock the group_info alloc_sem of all the groups
- * belonging to the same buddy cache page. This
- * make sure other parallel operation on the buddy
- * cache doesn't happen whild holding the buddy cache
- * lock
+ * Lock the buddy and bitmap pages. This make sure other parallel init_group
+ * on the same buddy page doesn't happen whild holding the buddy page lock.
+ * Return locked buddy and bitmap pages on e4b struct. If buddy and bitmap
+ * are on the same page e4b->bd_buddy_page is NULL and return value is 0.
*/
-static int ext4_mb_get_buddy_cache_lock(struct super_block *sb,
- ext4_group_t group)
+static int ext4_mb_get_buddy_page_lock(struct super_block *sb,
+ ext4_group_t group, struct ext4_buddy *e4b)
{
- int i;
- int block, pnum;
+ struct inode *inode = EXT4_SB(sb)->s_buddy_cache;
+ int block, pnum, poff;
int blocks_per_page;
- int groups_per_page;
- ext4_group_t ngroups = ext4_get_groups_count(sb);
- ext4_group_t first_group;
- struct ext4_group_info *grp;
+ struct page *page;
+
+ e4b->bd_buddy_page = NULL;
+ e4b->bd_bitmap_page = NULL;
blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
/*
*/
block = group * 2;
pnum = block / blocks_per_page;
- first_group = pnum * blocks_per_page / 2;
-
- groups_per_page = blocks_per_page >> 1;
- if (groups_per_page == 0)
- groups_per_page = 1;
- /* read all groups the page covers into the cache */
- for (i = 0; i < groups_per_page; i++) {
+ poff = block % blocks_per_page;
+ page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
+ if (!page)
+ return -EIO;
+ BUG_ON(page->mapping != inode->i_mapping);
+ e4b->bd_bitmap_page = page;
+ e4b->bd_bitmap = page_address(page) + (poff * sb->s_blocksize);
- if ((first_group + i) >= ngroups)
- break;
- grp = ext4_get_group_info(sb, first_group + i);
- /* take all groups write allocation
- * semaphore. This make sure there is
- * no block allocation going on in any
- * of that groups
- */
- down_write_nested(&grp->alloc_sem, i);
+ if (blocks_per_page >= 2) {
+ /* buddy and bitmap are on the same page */
+ return 0;
}
- return i;
+
+ block++;
+ pnum = block / blocks_per_page;
+ poff = block % blocks_per_page;
+ page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
+ if (!page)
+ return -EIO;
+ BUG_ON(page->mapping != inode->i_mapping);
+ e4b->bd_buddy_page = page;
+ return 0;
}
-static void ext4_mb_put_buddy_cache_lock(struct super_block *sb,
- ext4_group_t group, int locked_group)
+static void ext4_mb_put_buddy_page_lock(struct ext4_buddy *e4b)
{
- int i;
- int block, pnum;
- int blocks_per_page;
- ext4_group_t first_group;
- struct ext4_group_info *grp;
-
- blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
- /*
- * the buddy cache inode stores the block bitmap
- * and buddy information in consecutive blocks.
- * So for each group we need two blocks.
- */
- block = group * 2;
- pnum = block / blocks_per_page;
- first_group = pnum * blocks_per_page / 2;
- /* release locks on all the groups */
- for (i = 0; i < locked_group; i++) {
-
- grp = ext4_get_group_info(sb, first_group + i);
- /* take all groups write allocation
- * semaphore. This make sure there is
- * no block allocation going on in any
- * of that groups
- */
- up_write(&grp->alloc_sem);
+ if (e4b->bd_bitmap_page) {
+ unlock_page(e4b->bd_bitmap_page);
+ page_cache_release(e4b->bd_bitmap_page);
+ }
+ if (e4b->bd_buddy_page) {
+ unlock_page(e4b->bd_buddy_page);
+ page_cache_release(e4b->bd_buddy_page);
}
-
}
/*
int ext4_mb_init_group(struct super_block *sb, ext4_group_t group)
{
- int ret = 0;
- void *bitmap;
- int blocks_per_page;
- int block, pnum, poff;
- int num_grp_locked = 0;
struct ext4_group_info *this_grp;
- struct ext4_sb_info *sbi = EXT4_SB(sb);
- struct inode *inode = sbi->s_buddy_cache;
- struct page *page = NULL, *bitmap_page = NULL;
+ struct ext4_buddy e4b;
+ struct page *page;
+ int ret = 0;
mb_debug(1, "init group %u\n", group);
- blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
this_grp = ext4_get_group_info(sb, group);
/*
* This ensures that we don't reinit the buddy cache
* page which map to the group from which we are already
* allocating. If we are looking at the buddy cache we would
* have taken a reference using ext4_mb_load_buddy and that
- * would have taken the alloc_sem lock.
+ * would have pinned buddy page to page cache.
*/
- num_grp_locked = ext4_mb_get_buddy_cache_lock(sb, group);
- if (!EXT4_MB_GRP_NEED_INIT(this_grp)) {
+ ret = ext4_mb_get_buddy_page_lock(sb, group, &e4b);
+ if (ret || !EXT4_MB_GRP_NEED_INIT(this_grp)) {
/*
* somebody initialized the group
* return without doing anything
*/
- ret = 0;
goto err;
}
- /*
- * the buddy cache inode stores the block bitmap
- * and buddy information in consecutive blocks.
- * So for each group we need two blocks.
- */
- block = group * 2;
- pnum = block / blocks_per_page;
- poff = block % blocks_per_page;
- page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
- if (page) {
- BUG_ON(page->mapping != inode->i_mapping);
- ret = ext4_mb_init_cache(page, NULL);
- if (ret) {
- unlock_page(page);
- goto err;
- }
- unlock_page(page);
- }
- if (page == NULL || !PageUptodate(page)) {
+
+ page = e4b.bd_bitmap_page;
+ ret = ext4_mb_init_cache(page, NULL);
+ if (ret)
+ goto err;
+ if (!PageUptodate(page)) {
ret = -EIO;
goto err;
}
mark_page_accessed(page);
- bitmap_page = page;
- bitmap = page_address(page) + (poff * sb->s_blocksize);
- /* init buddy cache */
- block++;
- pnum = block / blocks_per_page;
- poff = block % blocks_per_page;
- page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS);
- if (page == bitmap_page) {
+ if (e4b.bd_buddy_page == NULL) {
/*
* If both the bitmap and buddy are in
* the same page we don't need to force
* init the buddy
*/
- unlock_page(page);
- } else if (page) {
- BUG_ON(page->mapping != inode->i_mapping);
- ret = ext4_mb_init_cache(page, bitmap);
- if (ret) {
- unlock_page(page);
- goto err;
- }
- unlock_page(page);
+ ret = 0;
+ goto err;
}
- if (page == NULL || !PageUptodate(page)) {
+ /* init buddy cache */
+ page = e4b.bd_buddy_page;
+ ret = ext4_mb_init_cache(page, e4b.bd_bitmap);
+ if (ret)
+ goto err;
+ if (!PageUptodate(page)) {
ret = -EIO;
goto err;
}
mark_page_accessed(page);
err:
- ext4_mb_put_buddy_cache_lock(sb, group, num_grp_locked);
- if (bitmap_page)
- page_cache_release(bitmap_page);
- if (page)
- page_cache_release(page);
+ ext4_mb_put_buddy_page_lock(&e4b);
return ret;
}
return 0;
err:
+ if (page)
+ page_cache_release(page);
if (e4b->bd_bitmap_page)
page_cache_release(e4b->bd_bitmap_page);
if (e4b->bd_buddy_page)
struct super_block *sb = journal->j_private;
struct ext4_buddy e4b;
struct ext4_group_info *db;
- int err, ret, count = 0, count2 = 0;
+ int err, count = 0, count2 = 0;
struct ext4_free_data *entry;
struct list_head *l, *ltmp;
mb_debug(1, "gonna free %u blocks in group %u (0x%p):",
entry->count, entry->group, entry);
- if (test_opt(sb, DISCARD)) {
- ret = ext4_issue_discard(sb, entry->group,
- entry->start_blk, entry->count);
- if (unlikely(ret == -EOPNOTSUPP)) {
- ext4_warning(sb, "discard not supported, "
- "disabling");
- clear_opt(sb, DISCARD);
- }
- }
+ if (test_opt(sb, DISCARD))
+ ext4_issue_discard(sb, entry->group,
+ entry->start_blk, entry->count);
err = ext4_mb_load_buddy(sb, entry->group, &e4b);
/* we expect to find existing buddy because it's pinned */
return;
}
+/**
+ * ext4_add_groupblocks() -- Add given blocks to an existing group
+ * @handle: handle to this transaction
+ * @sb: super block
+ * @block: start physcial block to add to the block group
+ * @count: number of blocks to free
+ *
+ * This marks the blocks as free in the bitmap and buddy.
+ */
+void ext4_add_groupblocks(handle_t *handle, struct super_block *sb,
+ ext4_fsblk_t block, unsigned long count)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *gd_bh;
+ ext4_group_t block_group;
+ ext4_grpblk_t bit;
+ unsigned int i;
+ struct ext4_group_desc *desc;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_buddy e4b;
+ int err = 0, ret, blk_free_count;
+ ext4_grpblk_t blocks_freed;
+ struct ext4_group_info *grp;
+
+ ext4_debug("Adding block(s) %llu-%llu\n", block, block + count - 1);
+
+ ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
+ grp = ext4_get_group_info(sb, block_group);
+ /*
+ * Check to see if we are freeing blocks across a group
+ * boundary.
+ */
+ if (bit + count > EXT4_BLOCKS_PER_GROUP(sb))
+ goto error_return;
+
+ bitmap_bh = ext4_read_block_bitmap(sb, block_group);
+ if (!bitmap_bh)
+ goto error_return;
+ desc = ext4_get_group_desc(sb, block_group, &gd_bh);
+ if (!desc)
+ goto error_return;
+
+ if (in_range(ext4_block_bitmap(sb, desc), block, count) ||
+ in_range(ext4_inode_bitmap(sb, desc), block, count) ||
+ in_range(block, ext4_inode_table(sb, desc), sbi->s_itb_per_group) ||
+ in_range(block + count - 1, ext4_inode_table(sb, desc),
+ sbi->s_itb_per_group)) {
+ ext4_error(sb, "Adding blocks in system zones - "
+ "Block = %llu, count = %lu",
+ block, count);
+ goto error_return;
+ }
+
+ BUFFER_TRACE(bitmap_bh, "getting write access");
+ err = ext4_journal_get_write_access(handle, bitmap_bh);
+ if (err)
+ goto error_return;
+
+ /*
+ * We are about to modify some metadata. Call the journal APIs
+ * to unshare ->b_data if a currently-committing transaction is
+ * using it
+ */
+ BUFFER_TRACE(gd_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, gd_bh);
+ if (err)
+ goto error_return;
+
+ for (i = 0, blocks_freed = 0; i < count; i++) {
+ BUFFER_TRACE(bitmap_bh, "clear bit");
+ if (!mb_test_bit(bit + i, bitmap_bh->b_data)) {
+ ext4_error(sb, "bit already cleared for block %llu",
+ (ext4_fsblk_t)(block + i));
+ BUFFER_TRACE(bitmap_bh, "bit already cleared");
+ } else {
+ blocks_freed++;
+ }
+ }
+
+ err = ext4_mb_load_buddy(sb, block_group, &e4b);
+ if (err)
+ goto error_return;
+
+ /*
+ * need to update group_info->bb_free and bitmap
+ * with group lock held. generate_buddy look at
+ * them with group lock_held
+ */
+ ext4_lock_group(sb, block_group);
+ mb_clear_bits(bitmap_bh->b_data, bit, count);
+ mb_free_blocks(NULL, &e4b, bit, count);
+ blk_free_count = blocks_freed + ext4_free_blks_count(sb, desc);
+ ext4_free_blks_set(sb, desc, blk_free_count);
+ desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc);
+ ext4_unlock_group(sb, block_group);
+ percpu_counter_add(&sbi->s_freeblocks_counter, blocks_freed);
+
+ if (sbi->s_log_groups_per_flex) {
+ ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
+ atomic_add(blocks_freed,
+ &sbi->s_flex_groups[flex_group].free_blocks);
+ }
+
+ ext4_mb_unload_buddy(&e4b);
+
+ /* We dirtied the bitmap block */
+ BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
+ err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
+
+ /* And the group descriptor block */
+ BUFFER_TRACE(gd_bh, "dirtied group descriptor block");
+ ret = ext4_handle_dirty_metadata(handle, NULL, gd_bh);
+ if (!err)
+ err = ret;
+
+error_return:
+ brelse(bitmap_bh);
+ ext4_std_error(sb, err);
+ return;
+}
+
/**
* ext4_trim_extent -- function to TRIM one single free extent in the group
* @sb: super block for the file system
* one will allocate those blocks, mark it as used in buddy bitmap. This must
* be called with under the group lock.
*/
-static int ext4_trim_extent(struct super_block *sb, int start, int count,
- ext4_group_t group, struct ext4_buddy *e4b)
+static void ext4_trim_extent(struct super_block *sb, int start, int count,
+ ext4_group_t group, struct ext4_buddy *e4b)
{
struct ext4_free_extent ex;
- int ret = 0;
assert_spin_locked(ext4_group_lock_ptr(sb, group));
*/
mb_mark_used(e4b, &ex);
ext4_unlock_group(sb, group);
-
- ret = ext4_issue_discard(sb, group, start, count);
-
+ ext4_issue_discard(sb, group, start, count);
ext4_lock_group(sb, group);
mb_free_blocks(NULL, e4b, start, ex.fe_len);
- return ret;
}
/**
void *bitmap;
ext4_grpblk_t next, count = 0;
ext4_group_t group;
- int ret = 0;
BUG_ON(e4b == NULL);
next = mb_find_next_bit(bitmap, max, start);
if ((next - start) >= minblocks) {
- ret = ext4_trim_extent(sb, start,
- next - start, group, e4b);
- if (ret < 0)
- break;
+ ext4_trim_extent(sb, start,
+ next - start, group, e4b);
count += next - start;
}
start = next + 1;
ext4_debug("trimmed %d blocks in the group %d\n",
count, group);
- if (ret < 0)
- count = ret;
-
return count;
}
git.openpandora.org / pandora-kernel.git / blobdiff