diff options
Diffstat (limited to 'fs/ext4/extents.c')
| -rw-r--r-- | fs/ext4/extents.c | 392 |
1 files changed, 311 insertions, 81 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 612c3d2c382..ea2ce3c0ae6 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -40,6 +40,7 @@ #include <linux/slab.h> #include <linux/falloc.h> #include <asm/uaccess.h> +#include <linux/fiemap.h> #include "ext4_jbd2.h" #include "ext4_extents.h" @@ -383,8 +384,8 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path) ext_debug("\n"); } #else -#define ext4_ext_show_path(inode,path) -#define ext4_ext_show_leaf(inode,path) +#define ext4_ext_show_path(inode, path) +#define ext4_ext_show_leaf(inode, path) #endif void ext4_ext_drop_refs(struct ext4_ext_path *path) @@ -440,9 +441,10 @@ ext4_ext_binsearch_idx(struct inode *inode, for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) { if (k != 0 && le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) { - printk("k=%d, ix=0x%p, first=0x%p\n", k, - ix, EXT_FIRST_INDEX(eh)); - printk("%u <= %u\n", + printk(KERN_DEBUG "k=%d, ix=0x%p, " + "first=0x%p\n", k, + ix, EXT_FIRST_INDEX(eh)); + printk(KERN_DEBUG "%u <= %u\n", le32_to_cpu(ix->ei_block), le32_to_cpu(ix[-1].ei_block)); } @@ -1475,7 +1477,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, struct ext4_ext_path *path, struct ext4_extent *newext) { - struct ext4_extent_header * eh; + struct ext4_extent_header *eh; struct ext4_extent *ex, *fex; struct ext4_extent *nearex; /* nearest extent */ struct ext4_ext_path *npath = NULL; @@ -1625,6 +1627,113 @@ cleanup: return err; } +int ext4_ext_walk_space(struct inode *inode, ext4_lblk_t block, + ext4_lblk_t num, ext_prepare_callback func, + void *cbdata) +{ + struct ext4_ext_path *path = NULL; + struct ext4_ext_cache cbex; + struct ext4_extent *ex; + ext4_lblk_t next, start = 0, end = 0; + ext4_lblk_t last = block + num; + int depth, exists, err = 0; + + BUG_ON(func == NULL); + BUG_ON(inode == NULL); + + while (block < last && block != EXT_MAX_BLOCK) { + num = last - block; + /* find extent for this block */ + path = ext4_ext_find_extent(inode, block, path); + if (IS_ERR(path)) { + err = PTR_ERR(path); + path = NULL; + break; + } + + depth = ext_depth(inode); + BUG_ON(path[depth].p_hdr == NULL); + ex = path[depth].p_ext; + next = ext4_ext_next_allocated_block(path); + + exists = 0; + if (!ex) { + /* there is no extent yet, so try to allocate + * all requested space */ + start = block; + end = block + num; + } else if (le32_to_cpu(ex->ee_block) > block) { + /* need to allocate space before found extent */ + start = block; + end = le32_to_cpu(ex->ee_block); + if (block + num < end) + end = block + num; + } else if (block >= le32_to_cpu(ex->ee_block) + + ext4_ext_get_actual_len(ex)) { + /* need to allocate space after found extent */ + start = block; + end = block + num; + if (end >= next) + end = next; + } else if (block >= le32_to_cpu(ex->ee_block)) { + /* + * some part of requested space is covered + * by found extent + */ + start = block; + end = le32_to_cpu(ex->ee_block) + + ext4_ext_get_actual_len(ex); + if (block + num < end) + end = block + num; + exists = 1; + } else { + BUG(); + } + BUG_ON(end <= start); + + if (!exists) { + cbex.ec_block = start; + cbex.ec_len = end - start; + cbex.ec_start = 0; + cbex.ec_type = EXT4_EXT_CACHE_GAP; + } else { + cbex.ec_block = le32_to_cpu(ex->ee_block); + cbex.ec_len = ext4_ext_get_actual_len(ex); + cbex.ec_start = ext_pblock(ex); + cbex.ec_type = EXT4_EXT_CACHE_EXTENT; + } + + BUG_ON(cbex.ec_len == 0); + err = func(inode, path, &cbex, ex, cbdata); + ext4_ext_drop_refs(path); + + if (err < 0) + break; + + if (err == EXT_REPEAT) + continue; + else if (err == EXT_BREAK) { + err = 0; + break; + } + + if (ext_depth(inode) != depth) { + /* depth was changed. we have to realloc path */ + kfree(path); + path = NULL; + } + + block = cbex.ec_block + cbex.ec_len; + } + + if (path) { + ext4_ext_drop_refs(path); + kfree(path); + } + + return err; +} + static void ext4_ext_put_in_cache(struct inode *inode, ext4_lblk_t block, __u32 len, ext4_fsblk_t start, int type) @@ -1747,54 +1856,61 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, } /* - * ext4_ext_calc_credits_for_insert: - * This routine returns max. credits that the extent tree can consume. - * It should be OK for low-performance paths like ->writepage() - * To allow many writing processes to fit into a single transaction, - * the caller should calculate credits under i_data_sem and - * pass the actual path. + * ext4_ext_calc_credits_for_single_extent: + * This routine returns max. credits that needed to insert an extent + * to the extent tree. + * When pass the actual path, the caller should calculate credits + * under i_data_sem. */ -int ext4_ext_calc_credits_for_insert(struct inode *inode, +int ext4_ext_calc_credits_for_single_extent(struct inode *inode, int nrblocks, struct ext4_ext_path *path) { - int depth, needed; - if (path) { + int depth = ext_depth(inode); + int ret = 0; + /* probably there is space in leaf? */ - depth = ext_depth(inode); if (le16_to_cpu(path[depth].p_hdr->eh_entries) - < le16_to_cpu(path[depth].p_hdr->eh_max)) - return 1; - } - - /* - * given 32-bit logical block (4294967296 blocks), max. tree - * can be 4 levels in depth -- 4 * 340^4 == 53453440000. - * Let's also add one more level for imbalance. - */ - depth = 5; + < le16_to_cpu(path[depth].p_hdr->eh_max)) { - /* allocation of new data block(s) */ - needed = 2; + /* + * There are some space in the leaf tree, no + * need to account for leaf block credit + * + * bitmaps and block group descriptor blocks + * and other metadat blocks still need to be + * accounted. + */ + /* 1 bitmap, 1 block group descriptor */ + ret = 2 + EXT4_META_TRANS_BLOCKS(inode->i_sb); + } + } - /* - * tree can be full, so it would need to grow in depth: - * we need one credit to modify old root, credits for - * new root will be added in split accounting - */ - needed += 1; + return ext4_chunk_trans_blocks(inode, nrblocks); +} - /* - * Index split can happen, we would need: - * allocate intermediate indexes (bitmap + group) - * + change two blocks at each level, but root (already included) - */ - needed += (depth * 2) + (depth * 2); +/* + * How many index/leaf blocks need to change/allocate to modify nrblocks? + * + * if nrblocks are fit in a single extent (chunk flag is 1), then + * in the worse case, each tree level index/leaf need to be changed + * if the tree split due to insert a new extent, then the old tree + * index/leaf need to be updated too + * + * If the nrblocks are discontiguous, they could cause + * the whole tree split more than once, but this is really rare. + */ +int ext4_ext_index_trans_blocks(struct inode *inode, int nrblocks, int chunk) +{ + int index; + int depth = ext_depth(inode); - /* any allocation modifies superblock */ - needed += 1; + if (chunk) + index = depth * 2; + else + index = depth * 3; - return needed; + return index; } static int ext4_remove_blocks(handle_t *handle, struct inode *inode, @@ -1921,9 +2037,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, correct_index = 1; credits += (ext_depth(inode)) + 1; } -#ifdef CONFIG_QUOTA credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); -#endif err = ext4_ext_journal_restart(handle, credits); if (err) @@ -2137,7 +2251,7 @@ void ext4_ext_init(struct super_block *sb) */ if (test_opt(sb, EXTENTS)) { - printk("EXT4-fs: file extents enabled"); + printk(KERN_INFO "EXT4-fs: file extents enabled"); #ifdef AGGRESSIVE_TEST printk(", aggressive tests"); #endif @@ -2691,11 +2805,8 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, goto out2; } /* - * Okay, we need to do block allocation. Lazily initialize the block - * allocation info here if necessary. + * Okay, we need to do block allocation. */ - if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info)) - ext4_init_block_alloc_info(inode); /* find neighbour allocated blocks */ ar.lleft = iblock; @@ -2755,7 +2866,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, /* free data blocks we just allocated */ /* not a good idea to call discard here directly, * but otherwise we'd need to call it every free() */ - ext4_mb_discard_inode_preallocations(inode); + ext4_discard_preallocations(inode); ext4_free_blocks(handle, inode, ext_pblock(&newex), ext4_ext_get_actual_len(&newex), 0); goto out2; @@ -2805,7 +2916,7 @@ void ext4_ext_truncate(struct inode *inode) /* * probably first extent we're gonna free will be last in block */ - err = ext4_writepage_trans_blocks(inode) + 3; + err = ext4_writepage_trans_blocks(inode); handle = ext4_journal_start(inode, err); if (IS_ERR(handle)) return; @@ -2819,7 +2930,7 @@ void ext4_ext_truncate(struct inode *inode) down_write(&EXT4_I(inode)->i_data_sem); ext4_ext_invalidate_cache(inode); - ext4_mb_discard_inode_preallocations(inode); + ext4_discard_preallocations(inode); /* * TODO: optimization is possible here. @@ -2858,27 +2969,6 @@ out_stop: ext4_journal_stop(handle); } -/* - * ext4_ext_writepage_trans_blocks: - * calculate max number of blocks we could modify - * in order to allocate new block for an inode - */ -int ext4_ext_writepage_trans_blocks(struct inode *inode, int num) -{ - int needed; - - needed = ext4_ext_calc_credits_for_insert(inode, NULL); - - /* caller wants to allocate num blocks, but note it includes sb */ - needed = needed * num - (num - 1); - -#ifdef CONFIG_QUOTA - needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb); -#endif - - return needed; -} - static void ext4_falloc_update_inode(struct inode *inode, int mode, loff_t new_size, int update_ctime) { @@ -2893,10 +2983,11 @@ static void ext4_falloc_update_inode(struct inode *inode, * Update only when preallocation was requested beyond * the file size. */ - if (!(mode & FALLOC_FL_KEEP_SIZE) && - new_size > i_size_read(inode)) { - i_size_write(inode, new_size); - EXT4_I(inode)->i_disksize = new_size; + if (!(mode & FALLOC_FL_KEEP_SIZE)) { + if (new_size > i_size_read(inode)) + i_size_write(inode, new_size); + if (new_size > EXT4_I(inode)->i_disksize) + ext4_update_i_disksize(inode, new_size); } } @@ -2939,10 +3030,9 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) - block; /* - * credits to insert 1 extent into extent tree + buffers to be able to - * modify 1 super block, 1 block bitmap and 1 group descriptor. + * credits to insert 1 extent into extent tree */ - credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + 3; + credits = ext4_chunk_trans_blocks(inode, max_blocks); mutex_lock(&inode->i_mutex); retry: while (ret >= 0 && ret < max_blocks) { @@ -2989,3 +3079,143 @@ retry: mutex_unlock(&inode->i_mutex); return ret > 0 ? ret2 : ret; } + +/* + * Callback function called for each extent to gather FIEMAP information. + */ +int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path, + struct ext4_ext_cache *newex, struct ext4_extent *ex, + void *data) +{ + struct fiemap_extent_info *fieinfo = data; + unsigned long blksize_bits = inode->i_sb->s_blocksize_bits; + __u64 logical; + __u64 physical; + __u64 length; + __u32 flags = 0; + int error; + + logical = (__u64)newex->ec_block << blksize_bits; + + if (newex->ec_type == EXT4_EXT_CACHE_GAP) { + pgoff_t offset; + struct page *page; + struct buffer_head *bh = NULL; + + offset = logical >> PAGE_SHIFT; + page = find_get_page(inode->i_mapping, offset); + if (!page || !page_has_buffers(page)) + return EXT_CONTINUE; + + bh = page_buffers(page); + + if (!bh) + return EXT_CONTINUE; + + if (buffer_delay(bh)) { + flags |= FIEMAP_EXTENT_DELALLOC; + page_cache_release(page); + } else { + page_cache_release(page); + return EXT_CONTINUE; + } + } + + physical = (__u64)newex->ec_start << blksize_bits; + length = (__u64)newex->ec_len << blksize_bits; + + if (ex && ext4_ext_is_uninitialized(ex)) + flags |= FIEMAP_EXTENT_UNWRITTEN; + + /* + * If this extent reaches EXT_MAX_BLOCK, it must be last. + * + * Or if ext4_ext_next_allocated_block is EXT_MAX_BLOCK, + * this also indicates no more allocated blocks. + * + * XXX this might miss a single-block extent at EXT_MAX_BLOCK + */ + if (logical + length - 1 == EXT_MAX_BLOCK || + ext4_ext_next_allocated_block(path) == EXT_MAX_BLOCK) + flags |= FIEMAP_EXTENT_LAST; + + error = fiemap_fill_next_extent(fieinfo, logical, physical, + length, flags); + if (error < 0) + return error; + if (error == 1) + return EXT_BREAK; + + return EXT_CONTINUE; +} + +/* fiemap flags we can handle specified here */ +#define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR) + +int ext4_xattr_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo) +{ + __u64 physical = 0; + __u64 length; + __u32 flags = FIEMAP_EXTENT_LAST; + int blockbits = inode->i_sb->s_blocksize_bits; + int error = 0; + + /* in-inode? */ + if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) { + struct ext4_iloc iloc; + int offset; /* offset of xattr in inode */ + + error = ext4_get_inode_loc(inode, &iloc); + if (error) + return error; + physical = iloc.bh->b_blocknr << blockbits; + offset = EXT4_GOOD_OLD_INODE_SIZE + + EXT4_I(inode)->i_extra_isize; + physical += offset; + length = EXT4_SB(inode->i_sb)->s_inode_size - offset; + flags |= FIEMAP_EXTENT_DATA_INLINE; + } else { /* external block */ + physical = EXT4_I(inode)->i_file_acl << blockbits; + length = inode->i_sb->s_blocksize; + } + + if (physical) + error = fiemap_fill_next_extent(fieinfo, 0, physical, + length, flags); + return (error < 0 ? error : 0); +} + +int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, + __u64 start, __u64 len) +{ + ext4_lblk_t start_blk; + ext4_lblk_t len_blks; + int error = 0; + + /* fallback to generic here if not in extents fmt */ + if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) + return generic_block_fiemap(inode, fieinfo, start, len, + ext4_get_block); + + if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS)) + return -EBADR; + + if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) { + error = ext4_xattr_fiemap(inode, fieinfo); + } else { + start_blk = start >> inode->i_sb->s_blocksize_bits; + len_blks = len >> inode->i_sb->s_blocksize_bits; + + /* + * Walk the extent tree gathering extent information. + * ext4_ext_fiemap_cb will push extents back to user. + */ + down_write(&EXT4_I(inode)->i_data_sem); + error = ext4_ext_walk_space(inode, start_blk, len_blks, + ext4_ext_fiemap_cb, fieinfo); + up_write(&EXT4_I(inode)->i_data_sem); + } + + return error; +} + |