diff options
Diffstat (limited to 'fs/ext4/balloc.c')
| -rw-r--r-- | fs/ext4/balloc.c | 2263 |
1 files changed, 553 insertions, 1710 deletions
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 0737e05ba3d..fca382037dd 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -15,18 +15,40 @@ #include <linux/capability.h> #include <linux/fs.h> #include <linux/jbd2.h> -#include <linux/ext4_fs.h> -#include <linux/ext4_jbd2.h> #include <linux/quotaops.h> #include <linux/buffer_head.h> +#include "ext4.h" +#include "ext4_jbd2.h" +#include "mballoc.h" -#include "group.h" +#include <trace/events/ext4.h> + +static unsigned ext4_num_base_meta_clusters(struct super_block *sb, + ext4_group_t block_group); /* * balloc.c contains the blocks allocation and deallocation routines */ /* - * Calculate the block group number and offset, given a block number + * Calculate block group number for a given block number + */ +ext4_group_t ext4_get_group_number(struct super_block *sb, + ext4_fsblk_t block) +{ + ext4_group_t group; + + if (test_opt2(sb, STD_GROUP_SIZE)) + group = (block - + le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) >> + (EXT4_BLOCK_SIZE_BITS(sb) + EXT4_CLUSTER_BITS(sb) + 3); + else + ext4_get_group_no_and_offset(sb, block, &group, NULL); + return group; +} + +/* + * Calculate the block group number and offset into the block/cluster + * allocation bitmap, given a block number */ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, ext4_group_t *blockgrpp, ext4_grpblk_t *offsetp) @@ -35,7 +57,8 @@ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, ext4_grpblk_t offset; blocknr = blocknr - le32_to_cpu(es->s_first_data_block); - offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)); + offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb)) >> + EXT4_SB(sb)->s_cluster_bits; if (offsetp) *offsetp = offset; if (blockgrpp) @@ -43,93 +66,195 @@ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr, } -/* Initializes an uninitialized block bitmap if given, and returns the - * number of blocks free in the group. */ -unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, - ext4_group_t block_group, struct ext4_group_desc *gdp) +/* + * Check whether the 'block' lives within the 'block_group'. Returns 1 if so + * and 0 otherwise. + */ +static inline int ext4_block_in_group(struct super_block *sb, + ext4_fsblk_t block, + ext4_group_t block_group) +{ + ext4_group_t actual_group; + + actual_group = ext4_get_group_number(sb, block); + return (actual_group == block_group) ? 1 : 0; +} + +/* Return the number of clusters used for file system metadata; this + * represents the overhead needed by the file system. + */ +static unsigned ext4_num_overhead_clusters(struct super_block *sb, + ext4_group_t block_group, + struct ext4_group_desc *gdp) { - unsigned long start; - int bit, bit_max; - unsigned free_blocks, group_blocks; + unsigned num_clusters; + int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c; + ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group); + ext4_fsblk_t itbl_blk; struct ext4_sb_info *sbi = EXT4_SB(sb); - if (bh) { - J_ASSERT_BH(bh, buffer_locked(bh)); - - /* If checksum is bad mark all blocks used to prevent allocation - * essentially implementing a per-group read-only flag. */ - if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { - ext4_error(sb, __FUNCTION__, - "Checksum bad for group %lu\n", block_group); - gdp->bg_free_blocks_count = 0; - gdp->bg_free_inodes_count = 0; - gdp->bg_itable_unused = 0; - memset(bh->b_data, 0xff, sb->s_blocksize); - return 0; + /* This is the number of clusters used by the superblock, + * block group descriptors, and reserved block group + * descriptor blocks */ + num_clusters = ext4_num_base_meta_clusters(sb, block_group); + + /* + * For the allocation bitmaps and inode table, we first need + * to check to see if the block is in the block group. If it + * is, then check to see if the cluster is already accounted + * for in the clusters used for the base metadata cluster, or + * if we can increment the base metadata cluster to include + * that block. Otherwise, we will have to track the cluster + * used for the allocation bitmap or inode table explicitly. + * Normally all of these blocks are contiguous, so the special + * case handling shouldn't be necessary except for *very* + * unusual file system layouts. + */ + if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) { + block_cluster = EXT4_B2C(sbi, + ext4_block_bitmap(sb, gdp) - start); + if (block_cluster < num_clusters) + block_cluster = -1; + else if (block_cluster == num_clusters) { + num_clusters++; + block_cluster = -1; } - memset(bh->b_data, 0, sb->s_blocksize); } - /* Check for superblock and gdt backups in this group */ - bit_max = ext4_bg_has_super(sb, block_group); + if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) { + inode_cluster = EXT4_B2C(sbi, + ext4_inode_bitmap(sb, gdp) - start); + if (inode_cluster < num_clusters) + inode_cluster = -1; + else if (inode_cluster == num_clusters) { + num_clusters++; + inode_cluster = -1; + } + } - if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || - block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * - sbi->s_desc_per_block) { - if (bit_max) { - bit_max += ext4_bg_num_gdb(sb, block_group); - bit_max += - le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); + itbl_blk = ext4_inode_table(sb, gdp); + for (i = 0; i < sbi->s_itb_per_group; i++) { + if (ext4_block_in_group(sb, itbl_blk + i, block_group)) { + c = EXT4_B2C(sbi, itbl_blk + i - start); + if ((c < num_clusters) || (c == inode_cluster) || + (c == block_cluster) || (c == itbl_cluster)) + continue; + if (c == num_clusters) { + num_clusters++; + continue; + } + num_clusters++; + itbl_cluster = c; } - } else { /* For META_BG_BLOCK_GROUPS */ - int group_rel = (block_group - - le32_to_cpu(sbi->s_es->s_first_meta_bg)) % - EXT4_DESC_PER_BLOCK(sb); - if (group_rel == 0 || group_rel == 1 || - (group_rel == EXT4_DESC_PER_BLOCK(sb) - 1)) - bit_max += 1; } - if (block_group == sbi->s_groups_count - 1) { + if (block_cluster != -1) + num_clusters++; + if (inode_cluster != -1) + num_clusters++; + + return num_clusters; +} + +static unsigned int num_clusters_in_group(struct super_block *sb, + ext4_group_t block_group) +{ + unsigned int blocks; + + if (block_group == ext4_get_groups_count(sb) - 1) { /* - * Even though mke2fs always initialize first and last group - * if some other tool enabled the EXT4_BG_BLOCK_UNINIT we need - * to make sure we calculate the right free blocks + * Even though mke2fs always initializes the first and + * last group, just in case some other tool was used, + * we need to make sure we calculate the right free + * blocks. */ - group_blocks = ext4_blocks_count(sbi->s_es) - - le32_to_cpu(sbi->s_es->s_first_data_block) - - (EXT4_BLOCKS_PER_GROUP(sb) * (sbi->s_groups_count -1)); - } else { - group_blocks = EXT4_BLOCKS_PER_GROUP(sb); + blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) - + ext4_group_first_block_no(sb, block_group); + } else + blocks = EXT4_BLOCKS_PER_GROUP(sb); + return EXT4_NUM_B2C(EXT4_SB(sb), blocks); +} + +/* Initializes an uninitialized block bitmap */ +static void ext4_init_block_bitmap(struct super_block *sb, + struct buffer_head *bh, + ext4_group_t block_group, + struct ext4_group_desc *gdp) +{ + unsigned int bit, bit_max; + struct ext4_sb_info *sbi = EXT4_SB(sb); + ext4_fsblk_t start, tmp; + int flex_bg = 0; + struct ext4_group_info *grp; + + J_ASSERT_BH(bh, buffer_locked(bh)); + + /* If checksum is bad mark all blocks used to prevent allocation + * essentially implementing a per-group read-only flag. */ + if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) { + ext4_error(sb, "Checksum bad for group %u", block_group); + grp = ext4_get_group_info(sb, block_group); + if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) + percpu_counter_sub(&sbi->s_freeclusters_counter, + grp->bb_free); + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) { + int count; + count = ext4_free_inodes_count(sb, gdp); + percpu_counter_sub(&sbi->s_freeinodes_counter, + count); + } + set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT, &grp->bb_state); + return; } + memset(bh->b_data, 0, sb->s_blocksize); - free_blocks = group_blocks - bit_max; + bit_max = ext4_num_base_meta_clusters(sb, block_group); + for (bit = 0; bit < bit_max; bit++) + ext4_set_bit(bit, bh->b_data); - if (bh) { - for (bit = 0; bit < bit_max; bit++) - ext4_set_bit(bit, bh->b_data); + start = ext4_group_first_block_no(sb, block_group); - start = block_group * EXT4_BLOCKS_PER_GROUP(sb) + - le32_to_cpu(sbi->s_es->s_first_data_block); + if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) + flex_bg = 1; - /* Set bits for block and inode bitmaps, and inode table */ - ext4_set_bit(ext4_block_bitmap(sb, gdp) - start, bh->b_data); - ext4_set_bit(ext4_inode_bitmap(sb, gdp) - start, bh->b_data); - for (bit = (ext4_inode_table(sb, gdp) - start), - bit_max = bit + sbi->s_itb_per_group; bit < bit_max; bit++) - ext4_set_bit(bit, bh->b_data); + /* Set bits for block and inode bitmaps, and inode table */ + tmp = ext4_block_bitmap(sb, gdp); + if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); - /* - * Also if the number of blocks within the group is - * less than the blocksize * 8 ( which is the size - * of bitmap ), set rest of the block bitmap to 1 - */ - mark_bitmap_end(group_blocks, sb->s_blocksize * 8, bh->b_data); + tmp = ext4_inode_bitmap(sb, gdp); + if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); + + tmp = ext4_inode_table(sb, gdp); + for (; tmp < ext4_inode_table(sb, gdp) + + sbi->s_itb_per_group; tmp++) { + if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) + ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data); } - return free_blocks - sbi->s_itb_per_group - 2; + /* + * Also if the number of blocks within the group is less than + * the blocksize * 8 ( which is the size of bitmap ), set rest + * of the block bitmap to 1 + */ + ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group), + sb->s_blocksize * 8, bh->b_data); + ext4_block_bitmap_csum_set(sb, block_group, gdp, bh); + ext4_group_desc_csum_set(sb, block_group, gdp); } +/* Return the number of free blocks in a block group. It is used when + * the block bitmap is uninitialized, so we can't just count the bits + * in the bitmap. */ +unsigned ext4_free_clusters_after_init(struct super_block *sb, + ext4_group_t block_group, + struct ext4_group_desc *gdp) +{ + return num_clusters_in_group(sb, block_group) - + ext4_num_overhead_clusters(sb, block_group, gdp); +} /* * The free blocks are managed by bitmaps. A file system contains several @@ -142,9 +267,6 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, * when a file system is mounted (see ext4_fill_super). */ - -#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1) - /** * ext4_get_group_desc() -- load group descriptor from disk * @sb: super block @@ -152,32 +274,29 @@ unsigned ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, * @bh: pointer to the buffer head to store the block * group descriptor */ -struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb, +struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, ext4_group_t block_group, - struct buffer_head ** bh) + struct buffer_head **bh) { - unsigned long group_desc; - unsigned long offset; - struct ext4_group_desc * desc; + unsigned int group_desc; + unsigned int offset; + ext4_group_t ngroups = ext4_get_groups_count(sb); + struct ext4_group_desc *desc; struct ext4_sb_info *sbi = EXT4_SB(sb); - if (block_group >= sbi->s_groups_count) { - ext4_error (sb, "ext4_get_group_desc", - "block_group >= groups_count - " - "block_group = %lu, groups_count = %lu", - block_group, sbi->s_groups_count); + if (block_group >= ngroups) { + ext4_error(sb, "block_group >= groups_count - block_group = %u," + " groups_count = %u", block_group, ngroups); return NULL; } - smp_rmb(); group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb); offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1); if (!sbi->s_group_desc[group_desc]) { - ext4_error (sb, "ext4_get_group_desc", - "Group descriptor not loaded - " - "block_group = %lu, group_desc = %lu, desc = %lu", - block_group, group_desc, offset); + ext4_error(sb, "Group descriptor not loaded - " + "block_group = %u, group_desc = %u, desc = %u", + block_group, group_desc, offset); return NULL; } @@ -189,14 +308,19 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb, return desc; } -static int ext4_valid_block_bitmap(struct super_block *sb, - struct ext4_group_desc *desc, - unsigned int block_group, - struct buffer_head *bh) +/* + * Return the block number which was discovered to be invalid, or 0 if + * the block bitmap is valid. + */ +static ext4_fsblk_t ext4_valid_block_bitmap(struct super_block *sb, + struct ext4_group_desc *desc, + ext4_group_t block_group, + struct buffer_head *bh) { + struct ext4_sb_info *sbi = EXT4_SB(sb); ext4_grpblk_t offset; ext4_grpblk_t next_zero_bit; - ext4_fsblk_t bitmap_blk; + ext4_fsblk_t blk; ext4_fsblk_t group_first_block; if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { @@ -206,43 +330,77 @@ static int ext4_valid_block_bitmap(struct super_block *sb, * or it has to also read the block group where the bitmaps * are located to verify they are set. */ - return 1; + return 0; } group_first_block = ext4_group_first_block_no(sb, block_group); /* check whether block bitmap block number is set */ - bitmap_blk = ext4_block_bitmap(sb, desc); - offset = bitmap_blk - group_first_block; - if (!ext4_test_bit(offset, bh->b_data)) + blk = ext4_block_bitmap(sb, desc); + offset = blk - group_first_block; + if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data)) /* bad block bitmap */ - goto err_out; + return blk; /* check whether the inode bitmap block number is set */ - bitmap_blk = ext4_inode_bitmap(sb, desc); - offset = bitmap_blk - group_first_block; - if (!ext4_test_bit(offset, bh->b_data)) + blk = ext4_inode_bitmap(sb, desc); + offset = blk - group_first_block; + if (!ext4_test_bit(EXT4_B2C(sbi, offset), bh->b_data)) /* bad block bitmap */ - goto err_out; + return blk; /* check whether the inode table block number is set */ - bitmap_blk = ext4_inode_table(sb, desc); - offset = bitmap_blk - group_first_block; + blk = ext4_inode_table(sb, desc); + offset = blk - group_first_block; next_zero_bit = ext4_find_next_zero_bit(bh->b_data, - offset + EXT4_SB(sb)->s_itb_per_group, - offset); - if (next_zero_bit >= offset + EXT4_SB(sb)->s_itb_per_group) - /* good bitmap for inode tables */ - return 1; - -err_out: - ext4_error(sb, __FUNCTION__, - "Invalid block bitmap - " - "block_group = %d, block = %llu", - block_group, bitmap_blk); + EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group), + EXT4_B2C(sbi, offset)); + if (next_zero_bit < + EXT4_B2C(sbi, offset + EXT4_SB(sb)->s_itb_per_group)) + /* bad bitmap for inode tables */ + return blk; return 0; } + +static void ext4_validate_block_bitmap(struct super_block *sb, + struct ext4_group_desc *desc, + ext4_group_t block_group, + struct buffer_head *bh) +{ + ext4_fsblk_t blk; + struct ext4_group_info *grp = ext4_get_group_info(sb, block_group); + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (buffer_verified(bh)) + return; + + ext4_lock_group(sb, block_group); + blk = ext4_valid_block_bitmap(sb, desc, block_group, bh); + if (unlikely(blk != 0)) { + ext4_unlock_group(sb, block_group); + ext4_error(sb, "bg %u: block %llu: invalid block bitmap", + block_group, blk); + if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) + percpu_counter_sub(&sbi->s_freeclusters_counter, + grp->bb_free); + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + return; + } + if (unlikely(!ext4_block_bitmap_csum_verify(sb, block_group, + desc, bh))) { + ext4_unlock_group(sb, block_group); + ext4_error(sb, "bg %u: bad block bitmap checksum", block_group); + if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) + percpu_counter_sub(&sbi->s_freeclusters_counter, + grp->bb_free); + set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT, &grp->bb_state); + return; + } + set_buffer_verified(bh); + ext4_unlock_group(sb, block_group); +} + /** - * read_block_bitmap() + * ext4_read_block_bitmap_nowait() * @sb: super block * @block_group: given block group * @@ -252,10 +410,10 @@ err_out: * Return buffer_head on success or NULL in case of failure. */ struct buffer_head * -read_block_bitmap(struct super_block *sb, ext4_group_t block_group) +ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) { - struct ext4_group_desc * desc; - struct buffer_head * bh = NULL; + struct ext4_group_desc *desc; + struct buffer_head *bh; ext4_fsblk_t bitmap_blk; desc = ext4_get_group_desc(sb, block_group, NULL); @@ -264,1305 +422,161 @@ read_block_bitmap(struct super_block *sb, ext4_group_t block_group) bitmap_blk = ext4_block_bitmap(sb, desc); bh = sb_getblk(sb, bitmap_blk); if (unlikely(!bh)) { - ext4_error(sb, __FUNCTION__, - "Cannot read block bitmap - " - "block_group = %d, block_bitmap = %llu", - (int)block_group, (unsigned long long)bitmap_blk); + ext4_error(sb, "Cannot get buffer for block bitmap - " + "block_group = %u, block_bitmap = %llu", + block_group, bitmap_blk); return NULL; } - if (bh_uptodate_or_lock(bh)) - return bh; + if (bitmap_uptodate(bh)) + goto verify; + + lock_buffer(bh); + if (bitmap_uptodate(bh)) { + unlock_buffer(bh); + goto verify; + } + ext4_lock_group(sb, block_group); if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { ext4_init_block_bitmap(sb, bh, block_group, desc); + set_bitmap_uptodate(bh); set_buffer_uptodate(bh); + ext4_unlock_group(sb, block_group); unlock_buffer(bh); return bh; } - if (bh_submit_read(bh) < 0) { - put_bh(bh); - ext4_error(sb, __FUNCTION__, - "Cannot read block bitmap - " - "block_group = %d, block_bitmap = %llu", - (int)block_group, (unsigned long long)bitmap_blk); - return NULL; - } - if (!ext4_valid_block_bitmap(sb, desc, block_group, bh)) { - put_bh(bh); - return NULL; - } - - return bh; -} -/* - * The reservation window structure operations - * -------------------------------------------- - * Operations include: - * dump, find, add, remove, is_empty, find_next_reservable_window, etc. - * - * We use a red-black tree to represent per-filesystem reservation - * windows. - * - */ - -/** - * __rsv_window_dump() -- Dump the filesystem block allocation reservation map - * @rb_root: root of per-filesystem reservation rb tree - * @verbose: verbose mode - * @fn: function which wishes to dump the reservation map - * - * If verbose is turned on, it will print the whole block reservation - * windows(start, end). Otherwise, it will only print out the "bad" windows, - * those windows that overlap with their immediate neighbors. - */ -#if 1 -static void __rsv_window_dump(struct rb_root *root, int verbose, - const char *fn) -{ - struct rb_node *n; - struct ext4_reserve_window_node *rsv, *prev; - int bad; - -restart: - n = rb_first(root); - bad = 0; - prev = NULL; - - printk("Block Allocation Reservation Windows Map (%s):\n", fn); - while (n) { - rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node); - if (verbose) - printk("reservation window 0x%p " - "start: %llu, end: %llu\n", - rsv, rsv->rsv_start, rsv->rsv_end); - if (rsv->rsv_start && rsv->rsv_start >= rsv->rsv_end) { - printk("Bad reservation %p (start >= end)\n", - rsv); - bad = 1; - } - if (prev && prev->rsv_end >= rsv->rsv_start) { - printk("Bad reservation %p (prev->end >= start)\n", - rsv); - bad = 1; - } - if (bad) { - if (!verbose) { - printk("Restarting reservation walk in verbose mode\n"); - verbose = 1; - goto restart; - } - } - n = rb_next(n); - prev = rsv; - } - printk("Window map complete.\n"); - if (bad) - BUG(); -} -#define rsv_window_dump(root, verbose) \ - __rsv_window_dump((root), (verbose), __FUNCTION__) -#else -#define rsv_window_dump(root, verbose) do {} while (0) -#endif - -/** - * goal_in_my_reservation() - * @rsv: inode's reservation window - * @grp_goal: given goal block relative to the allocation block group - * @group: the current allocation block group - * @sb: filesystem super block - * - * Test if the given goal block (group relative) is within the file's - * own block reservation window range. - * - * If the reservation window is outside the goal allocation group, return 0; - * grp_goal (given goal block) could be -1, which means no specific - * goal block. In this case, always return 1. - * If the goal block is within the reservation window, return 1; - * otherwise, return 0; - */ -static int -goal_in_my_reservation(struct ext4_reserve_window *rsv, ext4_grpblk_t grp_goal, - ext4_group_t group, struct super_block *sb) -{ - ext4_fsblk_t group_first_block, group_last_block; - - group_first_block = ext4_group_first_block_no(sb, group); - group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); - - if ((rsv->_rsv_start > group_last_block) || - (rsv->_rsv_end < group_first_block)) - return 0; - if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start) - || (grp_goal + group_first_block > rsv->_rsv_end))) - return 0; - return 1; -} - -/** - * search_reserve_window() - * @rb_root: root of reservation tree - * @goal: target allocation block - * - * Find the reserved window which includes the goal, or the previous one - * if the goal is not in any window. - * Returns NULL if there are no windows or if all windows start after the goal. - */ -static struct ext4_reserve_window_node * -search_reserve_window(struct rb_root *root, ext4_fsblk_t goal) -{ - struct rb_node *n = root->rb_node; - struct ext4_reserve_window_node *rsv; - - if (!n) - return NULL; - - do { - rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node); - - if (goal < rsv->rsv_start) - n = n->rb_left; - else if (goal > rsv->rsv_end) - n = n->rb_right; - else - return rsv; - } while (n); - /* - * We've fallen off the end of the tree: the goal wasn't inside - * any particular node. OK, the previous node must be to one - * side of the interval containing the goal. If it's the RHS, - * we need to back up one. - */ - if (rsv->rsv_start > goal) { - n = rb_prev(&rsv->rsv_node); - rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node); - } - return rsv; -} - -/** - * ext4_rsv_window_add() -- Insert a window to the block reservation rb tree. - * @sb: super block - * @rsv: reservation window to add - * - * Must be called with rsv_lock hold. - */ -void ext4_rsv_window_add(struct super_block *sb, - struct ext4_reserve_window_node *rsv) -{ - struct rb_root *root = &EXT4_SB(sb)->s_rsv_window_root; - struct rb_node *node = &rsv->rsv_node; - ext4_fsblk_t start = rsv->rsv_start; - - struct rb_node ** p = &root->rb_node; - struct rb_node * parent = NULL; - struct ext4_reserve_window_node *this; - - while (*p) - { - parent = *p; - this = rb_entry(parent, struct ext4_reserve_window_node, rsv_node); - - if (start < this->rsv_start) - p = &(*p)->rb_left; - else if (start > this->rsv_end) - p = &(*p)->rb_right; - else { - rsv_window_dump(root, 1); - BUG(); - } - } - - rb_link_node(node, parent, p); - rb_insert_color(node, root); -} - -/** - * ext4_rsv_window_remove() -- unlink a window from the reservation rb tree - * @sb: super block - * @rsv: reservation window to remove - * - * Mark the block reservation window as not allocated, and unlink it - * from the filesystem reservation window rb tree. Must be called with - * rsv_lock hold. - */ -static void rsv_window_remove(struct super_block *sb, - struct ext4_reserve_window_node *rsv) -{ - rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED; - rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED; - rsv->rsv_alloc_hit = 0; - rb_erase(&rsv->rsv_node, &EXT4_SB(sb)->s_rsv_window_root); -} - -/* - * rsv_is_empty() -- Check if the reservation window is allocated. - * @rsv: given reservation window to check - * - * returns 1 if the end block is EXT4_RESERVE_WINDOW_NOT_ALLOCATED. - */ -static inline int rsv_is_empty(struct ext4_reserve_window *rsv) -{ - /* a valid reservation end block could not be 0 */ - return rsv->_rsv_end == EXT4_RESERVE_WINDOW_NOT_ALLOCATED; -} - -/** - * ext4_init_block_alloc_info() - * @inode: file inode structure - * - * Allocate and initialize the reservation window structure, and - * link the window to the ext4 inode structure at last - * - * The reservation window structure is only dynamically allocated - * and linked to ext4 inode the first time the open file - * needs a new block. So, before every ext4_new_block(s) call, for - * regular files, we should check whether the reservation window - * structure exists or not. In the latter case, this function is called. - * Fail to do so will result in block reservation being turned off for that - * open file. - * - * This function is called from ext4_get_blocks_handle(), also called - * when setting the reservation window size through ioctl before the file - * is open for write (needs block allocation). - * - * Needs down_write(i_data_sem) protection prior to call this function. - */ -void ext4_init_block_alloc_info(struct inode *inode) -{ - struct ext4_inode_info *ei = EXT4_I(inode); - struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info; - struct super_block *sb = inode->i_sb; - - block_i = kmalloc(sizeof(*block_i), GFP_NOFS); - if (block_i) { - struct ext4_reserve_window_node *rsv = &block_i->rsv_window_node; - - rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED; - rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED; - - /* - * if filesystem is mounted with NORESERVATION, the goal - * reservation window size is set to zero to indicate - * block reservation is off - */ - if (!test_opt(sb, RESERVATION)) - rsv->rsv_goal_size = 0; - else - rsv->rsv_goal_size = EXT4_DEFAULT_RESERVE_BLOCKS; - rsv->rsv_alloc_hit = 0; - block_i->last_alloc_logical_block = 0; - block_i->last_alloc_physical_block = 0; - } - ei->i_block_alloc_info = block_i; -} - -/** - * ext4_discard_reservation() - * @inode: inode - * - * Discard(free) block reservation window on last file close, or truncate - * or at last iput(). - * - * It is being called in three cases: - * ext4_release_file(): last writer close the file - * ext4_clear_inode(): last iput(), when nobody link to this file. - * ext4_truncate(): when the block indirect map is about to change. - * - */ -void ext4_discard_reservation(struct inode *inode) -{ - struct ext4_inode_info *ei = EXT4_I(inode); - struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info; - struct ext4_reserve_window_node *rsv; - spinlock_t *rsv_lock = &EXT4_SB(inode->i_sb)->s_rsv_window_lock; - - ext4_mb_discard_inode_preallocations(inode); - - if (!block_i) - return; - - rsv = &block_i->rsv_window_node; - if (!rsv_is_empty(&rsv->rsv_window)) { - spin_lock(rsv_lock); - if (!rsv_is_empty(&rsv->rsv_window)) - rsv_window_remove(inode->i_sb, rsv); - spin_unlock(rsv_lock); - } -} - -/** - * ext4_free_blocks_sb() -- Free given blocks and update quota - * @handle: handle to this transaction - * @sb: super block - * @block: start physcial block to free - * @count: number of blocks to free - * @pdquot_freed_blocks: pointer to quota - */ -void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb, - ext4_fsblk_t block, unsigned long count, - unsigned long *pdquot_freed_blocks) -{ - struct buffer_head *bitmap_bh = NULL; - struct buffer_head *gd_bh; - ext4_group_t block_group; - ext4_grpblk_t bit; - unsigned long i; - unsigned long overflow; - struct ext4_group_desc * desc; - struct ext4_super_block * es; - struct ext4_sb_info *sbi; - int err = 0, ret; - ext4_grpblk_t group_freed; - - *pdquot_freed_blocks = 0; - sbi = EXT4_SB(sb); - es = sbi->s_es; - if (block < le32_to_cpu(es->s_first_data_block) || - block + count < block || - block + count > ext4_blocks_count(es)) { - ext4_error (sb, "ext4_free_blocks", - "Freeing blocks not in datazone - " - "block = %llu, count = %lu", block, count); - goto error_return; - } - - ext4_debug ("freeing block(s) %llu-%llu\n", block, block + count - 1); - -do_more: - overflow = 0; - ext4_get_group_no_and_offset(sb, block, &block_group, &bit); - /* - * Check to see if we are freeing blocks across a group - * boundary. - */ - if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) { - overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb); - count -= overflow; - } - brelse(bitmap_bh); - bitmap_bh = 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, "ext4_free_blocks", - "Freeing blocks in system zones - " - "Block = %llu, count = %lu", - block, count); - goto error_return; - } - - /* - * We are about to start releasing blocks in the bitmap, - * so we need undo access. - */ - /* @@@ check errors */ - BUFFER_TRACE(bitmap_bh, "getting undo access"); - err = ext4_journal_get_undo_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; - - jbd_lock_bh_state(bitmap_bh); - - for (i = 0, group_freed = 0; i < count; i++) { + ext4_unlock_group(sb, block_group); + if (buffer_uptodate(bh)) { /* - * An HJ special. This is expensive... + * if not uninit if bh is uptodate, + * bitmap is also uptodate */ -#ifdef CONFIG_JBD2_DEBUG - jbd_unlock_bh_state(bitmap_bh); - { - struct buffer_head *debug_bh; - debug_bh = sb_find_get_block(sb, block + i); - if (debug_bh) { - BUFFER_TRACE(debug_bh, "Deleted!"); - if (!bh2jh(bitmap_bh)->b_committed_data) - BUFFER_TRACE(debug_bh, - "No commited data in bitmap"); - BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap"); - __brelse(debug_bh); - } - } - jbd_lock_bh_state(bitmap_bh); -#endif - if (need_resched()) { - jbd_unlock_bh_state(bitmap_bh); - cond_resched(); - jbd_lock_bh_state(bitmap_bh); - } - /* @@@ This prevents newly-allocated data from being - * freed and then reallocated within the same - * transaction. - * - * Ideally we would want to allow that to happen, but to - * do so requires making jbd2_journal_forget() capable of - * revoking the queued write of a data block, which - * implies blocking on the journal lock. *forget() - * cannot block due to truncate races. - * - * Eventually we can fix this by making jbd2_journal_forget() - * return a status indicating whether or not it was able - * to revoke the buffer. On successful revoke, it is - * safe not to set the allocation bit in the committed - * bitmap, because we know that there is no outstanding - * activity on the buffer any more and so it is safe to - * reallocate it. - */ - BUFFER_TRACE(bitmap_bh, "set in b_committed_data"); - J_ASSERT_BH(bitmap_bh, - bh2jh(bitmap_bh)->b_committed_data != NULL); - ext4_set_bit_atomic(sb_bgl_lock(sbi, block_group), bit + i, - bh2jh(bitmap_bh)->b_committed_data); - - /* - * We clear the bit in the bitmap after setting the committed - * data bit, because this is the reverse order to that which - * the allocator uses. - */ - BUFFER_TRACE(bitmap_bh, "clear bit"); - if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group), - bit + i, bitmap_bh->b_data)) { - jbd_unlock_bh_state(bitmap_bh); - ext4_error(sb, __FUNCTION__, - "bit already cleared for block %llu", - (ext4_fsblk_t)(block + i)); - jbd_lock_bh_state(bitmap_bh); - BUFFER_TRACE(bitmap_bh, "bit already cleared"); - } else { - group_freed++; - } - } - jbd_unlock_bh_state(bitmap_bh); - - spin_lock(sb_bgl_lock(sbi, block_group)); - desc->bg_free_blocks_count = - cpu_to_le16(le16_to_cpu(desc->bg_free_blocks_count) + - group_freed); - desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc); - spin_unlock(sb_bgl_lock(sbi, block_group)); - percpu_counter_add(&sbi->s_freeblocks_counter, count); - - /* We dirtied the bitmap block */ - BUFFER_TRACE(bitmap_bh, "dirtied bitmap block"); - err = ext4_journal_dirty_metadata(handle, bitmap_bh); - - /* And the group descriptor block */ - BUFFER_TRACE(gd_bh, "dirtied group descriptor block"); - ret = ext4_journal_dirty_metadata(handle, gd_bh); - if (!err) err = ret; - *pdquot_freed_blocks += group_freed; - - if (overflow && !err) { - block += count; - count = overflow; - goto do_more; - } - sb->s_dirt = 1; -error_return: - brelse(bitmap_bh); - ext4_std_error(sb, err); - return; -} - -/** - * ext4_free_blocks() -- Free given blocks and update quota - * @handle: handle for this transaction - * @inode: inode - * @block: start physical block to free - * @count: number of blocks to count - * @metadata: Are these metadata blocks - */ -void ext4_free_blocks(handle_t *handle, struct inode *inode, - ext4_fsblk_t block, unsigned long count, - int metadata) -{ - struct super_block * sb; - unsigned long dquot_freed_blocks; - - /* this isn't the right place to decide whether block is metadata - * inode.c/extents.c knows better, but for safety ... */ - if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode) || - ext4_should_journal_data(inode)) - metadata = 1; - - sb = inode->i_sb; - - if (!test_opt(sb, MBALLOC) || !EXT4_SB(sb)->s_group_info) - ext4_free_blocks_sb(handle, sb, block, count, - &dquot_freed_blocks); - else - ext4_mb_free_blocks(handle, inode, block, count, - metadata, &dquot_freed_blocks); - if (dquot_freed_blocks) - DQUOT_FREE_BLOCK(inode, dquot_freed_blocks); - return; -} - -/** - * ext4_test_allocatable() - * @nr: given allocation block group - * @bh: bufferhead contains the bitmap of the given block group - * - * For ext4 allocations, we must not reuse any blocks which are - * allocated in the bitmap buffer's "last committed data" copy. This - * prevents deletes from freeing up the page for reuse until we have - * committed the delete transaction. - * - * If we didn't do this, then deleting something and reallocating it as - * data would allow the old block to be overwritten before the - * transaction committed (because we force data to disk before commit). - * This would lead to corruption if we crashed between overwriting the - * data and committing the delete. - * - * @@@ We may want to make this allocation behaviour conditional on - * data-writes at some point, and disable it for metadata allocations or - * sync-data inodes. - */ -static int ext4_test_allocatable(ext4_grpblk_t nr, struct buffer_head *bh) -{ - int ret; - struct journal_head *jh = bh2jh(bh); - - if (ext4_test_bit(nr, bh->b_data)) - return 0; - - jbd_lock_bh_state(bh); - if (!jh->b_committed_data) - ret = 1; - else - ret = !ext4_test_bit(nr, jh->b_committed_data); - jbd_unlock_bh_state(bh); - return ret; -} - -/** - * bitmap_search_next_usable_block() - * @start: the starting block (group relative) of the search - * @bh: bufferhead contains the block group bitmap - * @maxblocks: the ending block (group relative) of the reservation - * - * The bitmap search --- search forward alternately through the actual - * bitmap on disk and the last-committed copy in journal, until we find a - * bit free in both bitmaps. - */ -static ext4_grpblk_t -bitmap_search_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh, - ext4_grpblk_t maxblocks) -{ - ext4_grpblk_t next; - struct journal_head *jh = bh2jh(bh); - - while (start < maxblocks) { - next = ext4_find_next_zero_bit(bh->b_data, maxblocks, start); - if (next >= maxblocks) - return -1; - if (ext4_test_allocatable(next, bh)) - return next; - jbd_lock_bh_state(bh); - if (jh->b_committed_data) - start = ext4_find_next_zero_bit(jh->b_committed_data, - maxblocks, next); - jbd_unlock_bh_state(bh); - } - return -1; -} - -/** - * find_next_usable_block() - * @start: the starting block (group relative) to find next - * allocatable block in bitmap. - * @bh: bufferhead contains the block group bitmap - * @maxblocks: the ending block (group relative) for the search - * - * Find an allocatable block in a bitmap. We honor both the bitmap and - * its last-committed copy (if that exists), and perform the "most - * appropriate allocation" algorithm of looking for a free block near - * the initial goal; then for a free byte somewhere in the bitmap; then - * for any free bit in the bitmap. - */ -static ext4_grpblk_t -find_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh, - ext4_grpblk_t maxblocks) -{ - ext4_grpblk_t here, next; - char *p, *r; - - if (start > 0) { - /* - * The goal was occupied; search forward for a free - * block within the next XX blocks. - * - * end_goal is more or less random, but it has to be - * less than EXT4_BLOCKS_PER_GROUP. Aligning up to the - * next 64-bit boundary is simple.. - */ - ext4_grpblk_t end_goal = (start + 63) & ~63; - if (end_goal > maxblocks) - end_goal = maxblocks; - here = ext4_find_next_zero_bit(bh->b_data, end_goal, start); - if (here < end_goal && ext4_test_allocatable(here, bh)) - return here; - ext4_debug("Bit not found near goal\n"); + set_bitmap_uptodate(bh); + unlock_buffer(bh); + goto verify; } - - here = start; - if (here < 0) - here = 0; - - p = ((char *)bh->b_data) + (here >> 3); - r = memscan(p, 0, ((maxblocks + 7) >> 3) - (here >> 3)); - next = (r - ((char *)bh->b_data)) << 3; - - if (next < maxblocks && next >= start && ext4_test_allocatable(next, bh)) - return next; - /* - * The bitmap search --- search forward alternately through the actual - * bitmap and the last-committed copy until we find a bit free in - * both + * submit the buffer_head for reading */ - here = bitmap_search_next_usable_block(here, bh, maxblocks); - return here; + set_buffer_new(bh); + trace_ext4_read_block_bitmap_load(sb, block_group); + bh->b_end_io = ext4_end_bitmap_read; + get_bh(bh); + submit_bh(READ | REQ_META | REQ_PRIO, bh); + return bh; +verify: + ext4_validate_block_bitmap(sb, desc, block_group, bh); + if (buffer_verified(bh)) + return bh; + put_bh(bh); + return NULL; } -/** - * claim_block() - * @block: the free block (group relative) to allocate - * @bh: the bufferhead containts the block group bitmap - * - * We think we can allocate this block in this bitmap. Try to set the bit. - * If that succeeds then check that nobody has allocated and then freed the - * block since we saw that is was not marked in b_committed_data. If it _was_ - * allocated and freed then clear the bit in the bitmap again and return - * zero (failure). - */ -static inline int -claim_block(spinlock_t *lock, ext4_grpblk_t block, struct buffer_head *bh) +/* Returns 0 on success, 1 on error */ +int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group, + struct buffer_head *bh) { - struct journal_head *jh = bh2jh(bh); - int ret; + struct ext4_group_desc *desc; - if (ext4_set_bit_atomic(lock, block, bh->b_data)) + if (!buffer_new(bh)) return 0; - jbd_lock_bh_state(bh); - if (jh->b_committed_data && ext4_test_bit(block,jh->b_committed_data)) { - ext4_clear_bit_atomic(lock, block, bh->b_data); - ret = 0; - } else { - ret = 1; - } - jbd_unlock_bh_state(bh); - return ret; -} - -/** - * ext4_try_to_allocate() - * @sb: superblock - * @handle: handle to this transaction - * @group: given allocation block group - * @bitmap_bh: bufferhead holds the block bitmap - * @grp_goal: given target block within the group - * @count: target number of blocks to allocate - * @my_rsv: reservation window - * - * Attempt to allocate blocks within a give range. Set the range of allocation - * first, then find the first free bit(s) from the bitmap (within the range), - * and at last, allocate the blocks by claiming the found free bit as allocated. - * - * To set the range of this allocation: - * if there is a reservation window, only try to allocate block(s) from the - * file's own reservation window; - * Otherwise, the allocation range starts from the give goal block, ends at - * the block group's last block. - * - * If we failed to allocate the desired block then we may end up crossing to a - * new bitmap. In that case we must release write access to the old one via - * ext4_journal_release_buffer(), else we'll run out of credits. - */ -static ext4_grpblk_t -ext4_try_to_allocate(struct super_block *sb, handle_t *handle, - ext4_group_t group, struct buffer_head *bitmap_bh, - ext4_grpblk_t grp_goal, unsigned long *count, - struct ext4_reserve_window *my_rsv) -{ - ext4_fsblk_t group_first_block; - ext4_grpblk_t start, end; - unsigned long num = 0; - - /* we do allocation within the reservation window if we have a window */ - if (my_rsv) { - group_first_block = ext4_group_first_block_no(sb, group); - if (my_rsv->_rsv_start >= group_first_block) - start = my_rsv->_rsv_start - group_first_block; - else - /* reservation window cross group boundary */ - start = 0; - end = my_rsv->_rsv_end - group_first_block + 1; - if (end > EXT4_BLOCKS_PER_GROUP(sb)) - /* reservation window crosses group boundary */ - end = EXT4_BLOCKS_PER_GROUP(sb); - if ((start <= grp_goal) && (grp_goal < end)) - start = grp_goal; - else - grp_goal = -1; - } else { - if (grp_goal > 0) - start = grp_goal; - else - start = 0; - end = EXT4_BLOCKS_PER_GROUP(sb); - } - - BUG_ON(start > EXT4_BLOCKS_PER_GROUP(sb)); - -repeat: - if (grp_goal < 0 || !ext4_test_allocatable(grp_goal, bitmap_bh)) { - grp_goal = find_next_usable_block(start, bitmap_bh, end); - if (grp_goal < 0) - goto fail_access; - if (!my_rsv) { - int i; - - for (i = 0; i < 7 && grp_goal > start && - ext4_test_allocatable(grp_goal - 1, - bitmap_bh); - i++, grp_goal--) - ; - } - } - start = grp_goal; - - if (!claim_block(sb_bgl_lock(EXT4_SB(sb), group), - grp_goal, bitmap_bh)) { - /* - * The block was allocated by another thread, or it was - * allocated and then freed by another thread - */ - start++; - grp_goal++; - if (start >= end) - goto fail_access; - goto repeat; - } - num++; - grp_goal++; - while (num < *count && grp_goal < end - && ext4_test_allocatable(grp_goal, bitmap_bh) - && claim_block(sb_bgl_lock(EXT4_SB(sb), group), - grp_goal, bitmap_bh)) { - num++; - grp_goal++; - } - *count = num; - return grp_goal - num; -fail_access: - *count = num; - return -1; -} - -/** - * find_next_reservable_window(): - * find a reservable space within the given range. - * It does not allocate the reservation window for now: - * alloc_new_reservation() will do the work later. - * - * @search_head: the head of the searching list; - * This is not necessarily the list head of the whole filesystem - * - * We have both head and start_block to assist the search - * for the reservable space. The list starts from head, - * but we will shift to the place where start_block is, - * then start from there, when looking for a reservable space. - * - * @size: the target new reservation window size - * - * @group_first_block: the first block we consider to start - * the real search from - * - * @last_block: - * the maximum block number that our goal reservable space - * could start from. This is normally the last block in this - * group. The search will end when we found the start of next - * possible reservable space is out of this boundary. - * This could handle the cross boundary reservation window - * request. - * - * basically we search from the given range, rather than the whole - * reservation double linked list, (start_block, last_block) - * to find a free region that is of my size and has not - * been reserved. - * - */ -static int find_next_reservable_window( - struct ext4_reserve_window_node *search_head, - struct ext4_reserve_window_node *my_rsv, - struct super_block * sb, - ext4_fsblk_t start_block, - ext4_fsblk_t last_block) -{ - struct rb_node *next; - struct ext4_reserve_window_node *rsv, *prev; - ext4_fsblk_t cur; - int size = my_rsv->rsv_goal_size; - - /* TODO: make the start of the reservation window byte-aligned */ - /* cur = *start_block & ~7;*/ - cur = start_block; - rsv = search_head; - if (!rsv) - return -1; - - while (1) { - if (cur <= rsv->rsv_end) - cur = rsv->rsv_end + 1; - - /* TODO? - * in the case we could not find a reservable space - * that is what is expected, during the re-search, we could - * remember what's the largest reservable space we could have - * and return that one. - * - * For now it will fail if we could not find the reservable - * space with expected-size (or more)... - */ - if (cur > last_block) - return -1; /* fail */ - - prev = rsv; - next = rb_next(&rsv->rsv_node); - rsv = rb_entry(next,struct ext4_reserve_window_node,rsv_node); - - /* - * Reached the last reservation, we can just append to the - * previous one. - */ - if (!next) - break; - - if (cur + size <= rsv->rsv_start) { - /* - * Found a reserveable space big enough. We could - * have a reservation across the group boundary here - */ - break; - } - } - /* - * we come here either : - * when we reach the end of the whole list, - * and there is empty reservable space after last entry in the list. - * append it to the end of the list. - * - * or we found one reservable space in the middle of the list, - * return the reservation window that we could append to. - * succeed. - */ - - if ((prev != my_rsv) && (!rsv_is_empty(&my_rsv->rsv_window))) - rsv_window_remove(sb, my_rsv); - - /* - * Let's book the whole avaliable window for now. We will check the - * disk bitmap later and then, if there are free blocks then we adjust - * the window size if it's larger than requested. - * Otherwise, we will remove this node from the tree next time - * call find_next_reservable_window. - */ - my_rsv->rsv_start = cur; - my_rsv->rsv_end = cur + size - 1; - my_rsv->rsv_alloc_hit = 0; - - if (prev != my_rsv) - ext4_rsv_window_add(sb, my_rsv); - - return 0; -} - -/** - * alloc_new_reservation()--allocate a new reservation window - * - * To make a new reservation, we search part of the filesystem - * reservation list (the list that inside the group). We try to - * allocate a new reservation window near the allocation goal, - * or the beginning of the group, if there is no goal. - * - * We first find a reservable space after the goal, then from - * there, we check the bitmap for the first free block after - * it. If there is no free block until the end of group, then the - * whole group is full, we failed. Otherwise, check if the free - * block is inside the expected reservable space, if so, we - * succeed. - * If the first free block is outside the reservable space, then - * start from the first free block, we search for next available - * space, and go on. - * - * on succeed, a new reservation will be found and inserted into the list - * It contains at least one free block, and it does not overlap with other - * reservation windows. - * - * failed: we failed to find a reservation window in this group - * - * @rsv: the reservation - * - * @grp_goal: The goal (group-relative). It is where the search for a - * free reservable space should start from. - * if we have a grp_goal(grp_goal >0 ), then start from there, - * no grp_goal(grp_goal = -1), we start from the first block - * of the group. - * - * @sb: the super block - * @group: the group we are trying to allocate in - * @bitmap_bh: the block group block bitmap - * - */ -static int alloc_new_reservation(struct ext4_reserve_window_node *my_rsv, - ext4_grpblk_t grp_goal, struct super_block *sb, - ext4_group_t group, struct buffer_head *bitmap_bh) -{ - struct ext4_reserve_window_node *search_head; - ext4_fsblk_t group_first_block, group_end_block, start_block; - ext4_grpblk_t first_free_block; - struct rb_root *fs_rsv_root = &EXT4_SB(sb)->s_rsv_window_root; - unsigned long size; - int ret; - spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock; - - group_first_block = ext4_group_first_block_no(sb, group); - group_end_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); - - if (grp_goal < 0) - start_block = group_first_block; - else - start_block = grp_goal + group_first_block; - - size = my_rsv->rsv_goal_size; - - if (!rsv_is_empty(&my_rsv->rsv_window)) { - /* - * if the old reservation is cross group boundary - * and if the goal is inside the old reservation window, - * we will come here when we just failed to allocate from - * the first part of the window. We still have another part - * that belongs to the next group. In this case, there is no - * point to discard our window and try to allocate a new one - * in this group(which will fail). we should - * keep the reservation window, just simply move on. - * - * Maybe we could shift the start block of the reservation - * window to the first block of next group. - */ - - if ((my_rsv->rsv_start <= group_end_block) && - (my_rsv->rsv_end > group_end_block) && - (start_block >= my_rsv->rsv_start)) - return -1; - - if ((my_rsv->rsv_alloc_hit > - (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) { - /* - * if the previously allocation hit ratio is - * greater than 1/2, then we double the size of - * the reservation window the next time, - * otherwise we keep the same size window - */ - size = size * 2; - if (size > EXT4_MAX_RESERVE_BLOCKS) - size = EXT4_MAX_RESERVE_BLOCKS; - my_rsv->rsv_goal_size= size; - } - } - - spin_lock(rsv_lock); - /* - * shift the search start to the window near the goal block - */ - search_head = search_reserve_window(fs_rsv_root, start_block); - - /* - * find_next_reservable_window() simply finds a reservable window - * inside the given range(start_block, group_end_block). - * - * To make sure the reservation window has a free bit inside it, we - * need to check the bitmap after we found a reservable window. - */ -retry: - ret = find_next_reservable_window(search_head, my_rsv, sb, - start_block, group_end_block); - - if (ret == -1) { - if (!rsv_is_empty(&my_rsv->rsv_window)) - rsv_window_remove(sb, my_rsv); - spin_unlock(rsv_lock); - return -1; - } - - /* - * On success, find_next_reservable_window() returns the - * reservation window where there is a reservable space after it. - * Before we reserve this reservable space, we need - * to make sure there is at least a free block inside this region. - * - * searching the first free bit on the block bitmap and copy of - * last committed bitmap alternatively, until we found a allocatable - * block. Search start from the start block of the reservable space - * we just found. - */ - spin_unlock(rsv_lock); - first_free_block = bitmap_search_next_usable_block( - my_rsv->rsv_start - group_first_block, - bitmap_bh, group_end_block - group_first_block + 1); - - if (first_free_block < 0) { - /* - * no free block left on the bitmap, no point - * to reserve the space. return failed. - */ - spin_lock(rsv_lock); - if (!rsv_is_empty(&my_rsv->rsv_window)) - rsv_window_remove(sb, my_rsv); - spin_unlock(rsv_lock); - return -1; /* failed */ + desc = ext4_get_group_desc(sb, block_group, NULL); + if (!desc) + return 1; + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) { + ext4_error(sb, "Cannot read block bitmap - " + "block_group = %u, block_bitmap = %llu", + block_group, (unsigned long long) bh->b_blocknr); + return 1; } - - start_block = first_free_block + group_first_block; - /* - * check if the first free block is within the - * free space we just reserved - */ - if (start_block >= my_rsv->rsv_start && start_block <= my_rsv->rsv_end) - return 0; /* success */ - /* - * if the first free bit we found is out of the reservable space - * continue search for next reservable space, - * start from where the free block is, - * we also shift the list head to where we stopped last time - */ - search_head = my_rsv; - spin_lock(rsv_lock); - goto retry; + clear_buffer_new(bh); + /* Panic or remount fs read-only if block bitmap is invalid */ + ext4_validate_block_bitmap(sb, desc, block_group, bh); + /* ...but check for error just in case errors=continue. */ + return !buffer_verified(bh); } -/** - * try_to_extend_reservation() - * @my_rsv: given reservation window - * @sb: super block - * @size: the delta to extend - * - * Attempt to expand the reservation window large enough to have - * required number of free blocks - * - * Since ext4_try_to_allocate() will always allocate blocks within - * the reservation window range, if the window size is too small, - * multiple blocks allocation has to stop at the end of the reservation - * window. To make this more efficient, given the total number of - * blocks needed and the current size of the window, we try to - * expand the reservation window size if necessary on a best-effort - * basis before ext4_new_blocks() tries to allocate blocks, - */ -static void try_to_extend_reservation(struct ext4_reserve_window_node *my_rsv, - struct super_block *sb, int size) +struct buffer_head * +ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group) { - struct ext4_reserve_window_node *next_rsv; - struct rb_node *next; - spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock; - - if (!spin_trylock(rsv_lock)) - return; - - next = rb_next(&my_rsv->rsv_node); + struct buffer_head *bh; - if (!next) - my_rsv->rsv_end += size; - else { - next_rsv = rb_entry(next, struct ext4_reserve_window_node, rsv_node); - - if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size) - my_rsv->rsv_end += size; - else - my_rsv->rsv_end = next_rsv->rsv_start - 1; + bh = ext4_read_block_bitmap_nowait(sb, block_group); + if (!bh) + return NULL; + if (ext4_wait_block_bitmap(sb, block_group, bh)) { + put_bh(bh); + return NULL; } - spin_unlock(rsv_lock); + return bh; } /** - * ext4_try_to_allocate_with_rsv() - * @sb: superblock - * @handle: handle to this transaction - * @group: given allocation block group - * @bitmap_bh: bufferhead holds the block bitmap - * @grp_goal: given target block within the group - * @count: target number of blocks to allocate - * @my_rsv: reservation window - * @errp: pointer to store the error code - * - * This is the main function used to allocate a new block and its reservation - * window. - * - * Each time when a new block allocation is need, first try to allocate from - * its own reservation. If it does not have a reservation window, instead of - * looking for a free bit on bitmap first, then look up the reservation list to - * see if it is inside somebody else's reservation window, we try to allocate a - * reservation window for it starting from the goal first. Then do the block - * allocation within the reservation window. - * - * This will avoid keeping on searching the reservation list again and - * again when somebody is looking for a free block (without - * reservation), and there are lots of free blocks, but they are all - * being reserved. - * - * We use a red-black tree for the per-filesystem reservation list. + * ext4_has_free_clusters() + * @sbi: in-core super block structure. + * @nclusters: number of needed blocks + * @flags: flags from ext4_mb_new_blocks() * + * Check if filesystem has nclusters free & available for allocation. + * On success return 1, return 0 on failure. */ -static ext4_grpblk_t -ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle, - ext4_group_t group, struct buffer_head *bitmap_bh, - ext4_grpblk_t grp_goal, - struct ext4_reserve_window_node * my_rsv, - unsigned long *count, int *errp) +static int ext4_has_free_clusters(struct ext4_sb_info *sbi, + s64 nclusters, unsigned int flags) { - ext4_fsblk_t group_first_block, group_last_block; - ext4_grpblk_t ret = 0; - int fatal; - unsigned long num = *count; + s64 free_clusters, dirty_clusters, rsv, resv_clusters; + struct percpu_counter *fcc = &sbi->s_freeclusters_counter; + struct percpu_counter *dcc = &sbi->s_dirtyclusters_counter; - *errp = 0; + free_clusters = percpu_counter_read_positive(fcc); + dirty_clusters = percpu_counter_read_positive(dcc); + resv_clusters = atomic64_read(&sbi->s_resv_clusters); /* - * Make sure we use undo access for the bitmap, because it is critical - * that we do the frozen_data COW on bitmap buffers in all cases even - * if the buffer is in BJ_Forget state in the committing transaction. + * r_blocks_count should always be multiple of the cluster ratio so + * we are safe to do a plane bit shift only. */ - BUFFER_TRACE(bitmap_bh, "get undo access for new block"); - fatal = ext4_journal_get_undo_access(handle, bitmap_bh); - if (fatal) { - *errp = fatal; - return -1; - } + rsv = (ext4_r_blocks_count(sbi->s_es) >> sbi->s_cluster_bits) + + resv_clusters; - /* - * we don't deal with reservation when - * filesystem is mounted without reservation - * or the file is not a regular file - * or last attempt to allocate a block with reservation turned on failed - */ - if (my_rsv == NULL ) { - ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh, - grp_goal, count, NULL); - goto out; + if (free_clusters - (nclusters + rsv + dirty_clusters) < + EXT4_FREECLUSTERS_WATERMARK) { + free_clusters = percpu_counter_sum_positive(fcc); + dirty_clusters = percpu_counter_sum_positive(dcc); } - /* - * grp_goal is a group relative block number (if there is a goal) - * 0 <= grp_goal < EXT4_BLOCKS_PER_GROUP(sb) - * first block is a filesystem wide block number - * first block is the block number of the first block in this group + /* Check whether we have space after accounting for current + * dirty clusters & root reserved clusters. */ - group_first_block = ext4_group_first_block_no(sb, group); - group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1); + if (free_clusters >= (rsv + nclusters + dirty_clusters)) + return 1; - /* - * Basically we will allocate a new block from inode's reservation - * window. - * - * We need to allocate a new reservation window, if: - * a) inode does not have a reservation window; or - * b) last attempt to allocate a block from existing reservation - * failed; or - * c) we come here with a goal and with a reservation window - * - * We do not need to allocate a new reservation window if we come here - * at the beginning with a goal and the goal is inside the window, or - * we don't have a goal but already have a reservation window. - * then we could go to allocate from the reservation window directly. - */ - while (1) { - if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) || - !goal_in_my_reservation(&my_rsv->rsv_window, - grp_goal, group, sb)) { - if (my_rsv->rsv_goal_size < *count) - my_rsv->rsv_goal_size = *count; - ret = alloc_new_reservation(my_rsv, grp_goal, sb, - group, bitmap_bh); - if (ret < 0) - break; /* failed */ - - if (!goal_in_my_reservation(&my_rsv->rsv_window, - grp_goal, group, sb)) - grp_goal = -1; - } else if (grp_goal >= 0) { - int curr = my_rsv->rsv_end - - (grp_goal + group_first_block) + 1; - - if (curr < *count) - try_to_extend_reservation(my_rsv, sb, - *count - curr); - } + /* Hm, nope. Are (enough) root reserved clusters available? */ + if (uid_eq(sbi->s_resuid, current_fsuid()) || + (!gid_eq(sbi->s_resgid, GLOBAL_ROOT_GID) && in_group_p(sbi->s_resgid)) || + capable(CAP_SYS_RESOURCE) || + (flags & EXT4_MB_USE_ROOT_BLOCKS)) { - if ((my_rsv->rsv_start > group_last_block) || - (my_rsv->rsv_end < group_first_block)) { - rsv_window_dump(&EXT4_SB(sb)->s_rsv_window_root, 1); - BUG(); - } - ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh, - grp_goal, &num, &my_rsv->rsv_window); - if (ret >= 0) { - my_rsv->rsv_alloc_hit += num; - *count = num; - break; /* succeed */ - } - num = *count; + if (free_clusters >= (nclusters + dirty_clusters + + resv_clusters)) + return 1; } -out: - if (ret >= 0) { - BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for " - "bitmap block"); - fatal = ext4_journal_dirty_metadata(handle, bitmap_bh); - if (fatal) { - *errp = fatal; - return -1; - } - return ret; + /* No free blocks. Let's see if we can dip into reserved pool */ + if (flags & EXT4_MB_USE_RESERVED) { + if (free_clusters >= (nclusters + dirty_clusters)) + return 1; } - BUFFER_TRACE(bitmap_bh, "journal_release_buffer"); - ext4_journal_release_buffer(handle, bitmap_bh); - return ret; + return 0; } -/** - * ext4_has_free_blocks() - * @sbi: in-core super block structure. - * - * Check if filesystem has at least 1 free block available for allocation. - */ -static int ext4_has_free_blocks(struct ext4_sb_info *sbi) +int ext4_claim_free_clusters(struct ext4_sb_info *sbi, + s64 nclusters, unsigned int flags) { - ext4_fsblk_t free_blocks, root_blocks; - - free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter); - root_blocks = ext4_r_blocks_count(sbi->s_es); - if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) && - sbi->s_resuid != current->fsuid && - (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) { + if (ext4_has_free_clusters(sbi, nclusters, flags)) { + percpu_counter_add(&sbi->s_dirtyclusters_counter, nclusters); return 0; - } - return 1; + } else + return -ENOSPC; } /** @@ -1572,14 +586,16 @@ static int ext4_has_free_blocks(struct ext4_sb_info *sbi) * * ext4_should_retry_alloc() is called when ENOSPC is returned, and if * it is profitable to retry the operation, this function will wait - * for the current or commiting transaction to complete, and then + * for the current or committing transaction to complete, and then * return TRUE. * * if the total number of retries exceed three times, return FALSE. */ int ext4_should_retry_alloc(struct super_block *sb, int *retries) { - if (!ext4_has_free_blocks(EXT4_SB(sb)) || (*retries)++ > 3) + if (!ext4_has_free_clusters(EXT4_SB(sb), 1, 0) || + (*retries)++ > 3 || + !EXT4_SB(sb)->s_journal) return 0; jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id); @@ -1587,336 +603,67 @@ int ext4_should_retry_alloc(struct super_block *sb, int *retries) return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal); } -/** - * ext4_new_blocks_old() -- core block(s) allocation function - * @handle: handle to this transaction - * @inode: file inode - * @goal: given target block(filesystem wide) - * @count: target number of blocks to allocate - * @errp: error code +/* + * ext4_new_meta_blocks() -- allocate block for meta data (indexing) blocks * - * ext4_new_blocks uses a goal block to assist allocation. It tries to - * allocate block(s) from the block group contains the goal block first. If that - * fails, it will try to allocate block(s) from other block groups without - * any specific goal block. + * @handle: handle to this transaction + * @inode: file inode + * @goal: given target block(filesystem wide) + * @count: pointer to total number of clusters needed + * @errp: error code * + * Return 1st allocated block number on success, *count stores total account + * error stores in errp pointer */ -ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode, - ext4_fsblk_t goal, unsigned long *count, int *errp) -{ - struct buffer_head *bitmap_bh = NULL; - struct buffer_head *gdp_bh; - ext4_group_t group_no; - ext4_group_t goal_group; - ext4_grpblk_t grp_target_blk; /* blockgroup relative goal block */ - ext4_grpblk_t grp_alloc_blk; /* blockgroup-relative allocated block*/ - ext4_fsblk_t ret_block; /* filesyetem-wide allocated block */ - ext4_group_t bgi; /* blockgroup iteration index */ - int fatal = 0, err; - int performed_allocation = 0; - ext4_grpblk_t free_blocks; /* number of free blocks in a group */ - struct super_block *sb; - struct ext4_group_desc *gdp; - struct ext4_super_block *es; - struct ext4_sb_info *sbi; - struct ext4_reserve_window_node *my_rsv = NULL; - struct ext4_block_alloc_info *block_i; - unsigned short windowsz = 0; - ext4_group_t ngroups; - unsigned long num = *count; - - *errp = -ENOSPC; - sb = inode->i_sb; - if (!sb) { - printk("ext4_new_block: nonexistent device"); - return 0; - } - - /* - * Check quota for allocation of this block. - */ - if (DQUOT_ALLOC_BLOCK(inode, num)) { - *errp = -EDQUOT; - return 0; - } - - sbi = EXT4_SB(sb); - es = EXT4_SB(sb)->s_es; - ext4_debug("goal=%llu.\n", goal); - /* - * Allocate a block from reservation only when - * filesystem is mounted with reservation(default,-o reservation), and - * it's a regular file, and - * the desired window size is greater than 0 (One could use ioctl - * command EXT4_IOC_SETRSVSZ to set the window size to 0 to turn off - * reservation on that particular file) - */ - block_i = EXT4_I(inode)->i_block_alloc_info; - if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0)) - my_rsv = &block_i->rsv_window_node; - - if (!ext4_has_free_blocks(sbi)) { - *errp = -ENOSPC; - goto out; - } - - /* - * First, test whether the goal block is free. - */ - if (goal < le32_to_cpu(es->s_first_data_block) || - goal >= ext4_blocks_count(es)) - goal = le32_to_cpu(es->s_first_data_block); - ext4_get_group_no_and_offset(sb, goal, &group_no, &grp_target_blk); - goal_group = group_no; -retry_alloc: - gdp = ext4_get_group_desc(sb, group_no, &gdp_bh); - if (!gdp) - goto io_error; - - free_blocks = le16_to_cpu(gdp->bg_free_blocks_count); - /* - * if there is not enough free blocks to make a new resevation - * turn off reservation for this allocation - */ - if (my_rsv && (free_blocks < windowsz) - && (rsv_is_empty(&my_rsv->rsv_window))) - my_rsv = NULL; - - if (free_blocks > 0) { - bitmap_bh = read_block_bitmap(sb, group_no); - if (!bitmap_bh) - goto io_error; - grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle, - group_no, bitmap_bh, grp_target_blk, - my_rsv, &num, &fatal); - if (fatal) - goto out; - if (grp_alloc_blk >= 0) - goto allocated; - } - - ngroups = EXT4_SB(sb)->s_groups_count; - smp_rmb(); - - /* - * Now search the rest of the groups. We assume that - * group_no and gdp correctly point to the last group visited. - */ - for (bgi = 0; bgi < ngroups; bgi++) { - group_no++; - if (group_no >= ngroups) - group_no = 0; - gdp = ext4_get_group_desc(sb, group_no, &gdp_bh); - if (!gdp) - goto io_error; - free_blocks = le16_to_cpu(gdp->bg_free_blocks_count); - /* - * skip this group if the number of - * free blocks is less than half of the reservation - * window size. - */ - if (free_blocks <= (windowsz/2)) - continue; - - brelse(bitmap_bh); - bitmap_bh = read_block_bitmap(sb, group_no); - if (!bitmap_bh) - goto io_error; - /* - * try to allocate block(s) from this group, without a goal(-1). - */ - grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle, - group_no, bitmap_bh, -1, my_rsv, - &num, &fatal); - if (fatal) - goto out; - if (grp_alloc_blk >= 0) - goto allocated; - } - /* - * We may end up a bogus ealier ENOSPC error due to - * filesystem is "full" of reservations, but - * there maybe indeed free blocks avaliable on disk - * In this case, we just forget about the reservations - * just do block allocation as without reservations. - */ - if (my_rsv) { - my_rsv = NULL; - windowsz = 0; - group_no = goal_group; - goto retry_alloc; - } - /* No space left on the device */ - *errp = -ENOSPC; - goto out; - -allocated: - - ext4_debug("using block group %lu(%d)\n", - group_no, gdp->bg_free_blocks_count); - - BUFFER_TRACE(gdp_bh, "get_write_access"); - fatal = ext4_journal_get_write_access(handle, gdp_bh); - if (fatal) - goto out; - - ret_block = grp_alloc_blk + ext4_group_first_block_no(sb, group_no); - - if (in_range(ext4_block_bitmap(sb, gdp), ret_block, num) || - in_range(ext4_inode_bitmap(sb, gdp), ret_block, num) || - in_range(ret_block, ext4_inode_table(sb, gdp), - EXT4_SB(sb)->s_itb_per_group) || - in_range(ret_block + num - 1, ext4_inode_table(sb, gdp), - EXT4_SB(sb)->s_itb_per_group)) { - ext4_error(sb, "ext4_new_block", - "Allocating block in system zone - " - "blocks from %llu, length %lu", - ret_block, num); - goto out; - } - - performed_allocation = 1; - -#ifdef CONFIG_JBD2_DEBUG - { - struct buffer_head *debug_bh; - - /* Record bitmap buffer state in the newly allocated block */ - debug_bh = sb_find_get_block(sb, ret_block); - if (debug_bh) { - BUFFER_TRACE(debug_bh, "state when allocated"); - BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state"); - brelse(debug_bh); - } - } - jbd_lock_bh_state(bitmap_bh); - spin_lock(sb_bgl_lock(sbi, group_no)); - if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) { - int i; - - for (i = 0; i < num; i++) { - if (ext4_test_bit(grp_alloc_blk+i, - bh2jh(bitmap_bh)->b_committed_data)) { - printk("%s: block was unexpectedly set in " - "b_committed_data\n", __FUNCTION__); - } - } - } - ext4_debug("found bit %d\n", grp_alloc_blk); - spin_unlock(sb_bgl_lock(sbi, group_no)); - jbd_unlock_bh_state(bitmap_bh); -#endif - - if (ret_block + num - 1 >= ext4_blocks_count(es)) { - ext4_error(sb, "ext4_new_block", - "block(%llu) >= blocks count(%llu) - " - "block_group = %lu, es == %p ", ret_block, - ext4_blocks_count(es), group_no, es); - goto out; - } - - /* - * It is up to the caller to add the new buffer to a journal - * list of some description. We don't know in advance whether - * the caller wants to use it as metadata or data. - */ - spin_lock(sb_bgl_lock(sbi, group_no)); - if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) - gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); - gdp->bg_free_blocks_count = - cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)-num); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group_no, gdp); - spin_unlock(sb_bgl_lock(sbi, group_no)); - percpu_counter_sub(&sbi->s_freeblocks_counter, num); - - BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor"); - err = ext4_journal_dirty_metadata(handle, gdp_bh); - if (!fatal) - fatal = err; - - sb->s_dirt = 1; - if (fatal) - goto out; - - *errp = 0; - brelse(bitmap_bh); - DQUOT_FREE_BLOCK(inode, *count-num); - *count = num; - return ret_block; - -io_error: - *errp = -EIO; -out: - if (fatal) { - *errp = fatal; - ext4_std_error(sb, fatal); - } - /* - * Undo the block allocation - */ - if (!performed_allocation) - DQUOT_FREE_BLOCK(inode, *count); - brelse(bitmap_bh); - return 0; -} - -ext4_fsblk_t ext4_new_block(handle_t *handle, struct inode *inode, - ext4_fsblk_t goal, int *errp) +ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, + ext4_fsblk_t goal, unsigned int flags, + unsigned long *count, int *errp) { struct ext4_allocation_request ar; ext4_fsblk_t ret; - if (!test_opt(inode->i_sb, MBALLOC)) { - unsigned long count = 1; - ret = ext4_new_blocks_old(handle, inode, goal, &count, errp); - return ret; - } - memset(&ar, 0, sizeof(ar)); + /* Fill with neighbour allocated blocks */ ar.inode = inode; ar.goal = goal; - ar.len = 1; - ret = ext4_mb_new_blocks(handle, &ar, errp); - return ret; -} - -ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode, - ext4_fsblk_t goal, unsigned long *count, int *errp) -{ - struct ext4_allocation_request ar; - ext4_fsblk_t ret; + ar.len = count ? *count : 1; + ar.flags = flags; - if (!test_opt(inode->i_sb, MBALLOC)) { - ret = ext4_new_blocks_old(handle, inode, goal, count, errp); - return ret; - } - - memset(&ar, 0, sizeof(ar)); - ar.inode = inode; - ar.goal = goal; - ar.len = *count; ret = ext4_mb_new_blocks(handle, &ar, errp); - *count = ar.len; + if (count) + *count = ar.len; + /* + * Account for the allocated meta blocks. We will never + * fail EDQUOT for metdata, but we do account for it. + */ + if (!(*errp) && + ext4_test_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED)) { + spin_lock(&EXT4_I(inode)->i_block_reservation_lock); + EXT4_I(inode)->i_allocated_meta_blocks += ar.len; + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); + dquot_alloc_block_nofail(inode, + EXT4_C2B(EXT4_SB(inode->i_sb), ar.len)); + } return ret; } - /** - * ext4_count_free_blocks() -- count filesystem free blocks + * ext4_count_free_clusters() -- count filesystem free clusters * @sb: superblock * - * Adds up the number of free blocks from each block group. + * Adds up the number of free clusters from each block group. */ -ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) +ext4_fsblk_t ext4_count_free_clusters(struct super_block *sb) { ext4_fsblk_t desc_count; struct ext4_group_desc *gdp; ext4_group_t i; - ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count; + ext4_group_t ngroups = ext4_get_groups_count(sb); + struct ext4_group_info *grp; #ifdef EXT4FS_DEBUG struct ext4_super_block *es; ext4_fsblk_t bitmap_count; - unsigned long x; + unsigned int x; struct buffer_head *bitmap_bh = NULL; es = EXT4_SB(sb)->s_es; @@ -1924,36 +671,43 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) bitmap_count = 0; gdp = NULL; - smp_rmb(); for (i = 0; i < ngroups; i++) { gdp = ext4_get_group_desc(sb, i, NULL); if (!gdp) continue; - desc_count += le16_to_cpu(gdp->bg_free_blocks_count); + grp = NULL; + if (EXT4_SB(sb)->s_group_info) + grp = ext4_get_group_info(sb, i); + if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) + desc_count += ext4_free_group_clusters(sb, gdp); brelse(bitmap_bh); - bitmap_bh = read_block_bitmap(sb, i); + bitmap_bh = ext4_read_block_bitmap(sb, i); if (bitmap_bh == NULL) continue; - x = ext4_count_free(bitmap_bh, sb->s_blocksize); - printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n", - i, le16_to_cpu(gdp->bg_free_blocks_count), x); + x = ext4_count_free(bitmap_bh->b_data, + EXT4_CLUSTERS_PER_GROUP(sb) / 8); + printk(KERN_DEBUG "group %u: stored = %d, counted = %u\n", + i, ext4_free_group_clusters(sb, gdp), x); bitmap_count += x; } brelse(bitmap_bh); - printk("ext4_count_free_blocks: stored = %llu" - ", computed = %llu, %llu\n", - ext4_free_blocks_count(es), - desc_count, bitmap_count); + printk(KERN_DEBUG "ext4_count_free_clusters: stored = %llu" + ", computed = %llu, %llu\n", + EXT4_NUM_B2C(EXT4_SB(sb), ext4_free_blocks_count(es)), + desc_count, bitmap_count); return bitmap_count; #else desc_count = 0; - smp_rmb(); for (i = 0; i < ngroups; i++) { gdp = ext4_get_group_desc(sb, i, NULL); if (!gdp) continue; - desc_count += le16_to_cpu(gdp->bg_free_blocks_count); + grp = NULL; + if (EXT4_SB(sb)->s_group_info) + grp = ext4_get_group_info(sb, i); + if (!grp || !EXT4_MB_GRP_BBITMAP_CORRUPT(grp)) + desc_count += ext4_free_group_clusters(sb, gdp); } return desc_count; @@ -1962,21 +716,15 @@ ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb) static inline int test_root(ext4_group_t a, int b) { - int num = b; - - while (a > num) - num *= b; - return num == a; -} - -static int ext4_group_sparse(ext4_group_t group) -{ - if (group <= 1) - return 1; - if (!(group & 1)) - return 0; - return (test_root(group, 7) || test_root(group, 5) || - test_root(group, 3)); + while (1) { + if (a < b) + return 0; + if (a == b) + return 1; + if ((a % b) != 0) + return 0; + a = a / b; + } } /** @@ -1989,11 +737,26 @@ static int ext4_group_sparse(ext4_group_t group) */ int ext4_bg_has_super(struct super_block *sb, ext4_group_t group) { - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) && - !ext4_group_sparse(group)) + struct ext4_super_block *es = EXT4_SB(sb)->s_es; + + if (group == 0) + return 1; + if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_SPARSE_SUPER2)) { + if (group == le32_to_cpu(es->s_backup_bgs[0]) || + group == le32_to_cpu(es->s_backup_bgs[1])) + return 1; + return 0; + } + if ((group <= 1) || !EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) + return 1; + if (!(group & 1)) return 0; - return 1; + if (test_root(group, 3) || (test_root(group, 5)) || + test_root(group, 7)) + return 1; + + return 0; } static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, @@ -2011,7 +774,13 @@ static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, ext4_group_t group) { - return ext4_bg_has_super(sb, group) ? EXT4_SB(sb)->s_gdb_count : 0; + if (!ext4_bg_has_super(sb, group)) + return 0; + + if (EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG)) + return le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg); + else + return EXT4_SB(sb)->s_gdb_count; } /** @@ -2031,8 +800,82 @@ unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group) if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) || metagroup < first_meta_bg) - return ext4_bg_num_gdb_nometa(sb,group); + return ext4_bg_num_gdb_nometa(sb, group); return ext4_bg_num_gdb_meta(sb,group); } + +/* + * This function returns the number of file system metadata clusters at + * the beginning of a block group, including the reserved gdt blocks. + */ +static unsigned ext4_num_base_meta_clusters(struct super_block *sb, + ext4_group_t block_group) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + unsigned num; + + /* Check for superblock and gdt backups in this group */ + num = ext4_bg_has_super(sb, block_group); + + if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) || + block_group < le32_to_cpu(sbi->s_es->s_first_meta_bg) * + sbi->s_desc_per_block) { + if (num) { + num += ext4_bg_num_gdb(sb, block_group); + num += le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks); + } + } else { /* For META_BG_BLOCK_GROUPS */ + num += ext4_bg_num_gdb(sb, block_group); + } + return EXT4_NUM_B2C(sbi, num); +} +/** + * ext4_inode_to_goal_block - return a hint for block allocation + * @inode: inode for block allocation + * + * Return the ideal location to start allocating blocks for a + * newly created inode. + */ +ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + ext4_group_t block_group; + ext4_grpblk_t colour; + int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); + ext4_fsblk_t bg_start; + ext4_fsblk_t last_block; + + block_group = ei->i_block_group; + if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { + /* + * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME + * block groups per flexgroup, reserve the first block + * group for directories and special files. Regular + * files will start at the second block group. This + * tends to speed up directory access and improves + * fsck times. + */ + block_group &= ~(flex_size-1); + if (S_ISREG(inode->i_mode)) + block_group++; + } + bg_start = ext4_group_first_block_no(inode->i_sb, block_group); + last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; + + /* + * If we are doing delayed allocation, we don't need take + * colour into account. + */ + if (test_opt(inode->i_sb, DELALLOC)) + return bg_start; + + if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) + colour = (current->pid % 16) * + (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); + else + colour = (current->pid % 16) * ((last_block - bg_start) / 16); + return bg_start + colour; +} + |