diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index b9ce24129070bff5cee547a333139d9a4645d2c7..ba25832a756c4cd5729eeacd284ecbe9c25defe3 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include @@ -282,7 +283,7 @@ static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path) } else if (path->p_ext) { ext_debug(" %d:%d:%llu ", le32_to_cpu(path->p_ext->ee_block), - le16_to_cpu(path->p_ext->ee_len), + ext4_ext_get_actual_len(path->p_ext), ext_pblock(path->p_ext)); } else ext_debug(" []"); @@ -305,7 +306,7 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path) for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) { ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block), - le16_to_cpu(ex->ee_len), ext_pblock(ex)); + ext4_ext_get_actual_len(ex), ext_pblock(ex)); } ext_debug("\n"); } @@ -425,7 +426,7 @@ ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block) ext_debug(" -> %d:%llu:%d ", le32_to_cpu(path->p_ext->ee_block), ext_pblock(path->p_ext), - le16_to_cpu(path->p_ext->ee_len)); + ext4_ext_get_actual_len(path->p_ext)); #ifdef CHECK_BINSEARCH { @@ -686,7 +687,7 @@ static int ext4_ext_split(handle_t *handle, struct inode *inode, ext_debug("move %d:%llu:%d in new leaf %llu\n", le32_to_cpu(path[depth].p_ext->ee_block), ext_pblock(path[depth].p_ext), - le16_to_cpu(path[depth].p_ext->ee_len), + ext4_ext_get_actual_len(path[depth].p_ext), newblock); /*memmove(ex++, path[depth].p_ext++, sizeof(struct ext4_extent)); @@ -1106,7 +1107,19 @@ static int ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, struct ext4_extent *ex2) { - if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len) != + unsigned short ext1_ee_len, ext2_ee_len; + + /* + * Make sure that either both extents are uninitialized, or + * both are _not_. + */ + if (ext4_ext_is_uninitialized(ex1) ^ ext4_ext_is_uninitialized(ex2)) + return 0; + + ext1_ee_len = ext4_ext_get_actual_len(ex1); + ext2_ee_len = ext4_ext_get_actual_len(ex2); + + if (le32_to_cpu(ex1->ee_block) + ext1_ee_len != le32_to_cpu(ex2->ee_block)) return 0; @@ -1115,14 +1128,14 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, * as an RO_COMPAT feature, refuse to merge to extents if * this can result in the top bit of ee_len being set. */ - if (le16_to_cpu(ex1->ee_len) + le16_to_cpu(ex2->ee_len) > EXT_MAX_LEN) + if (ext1_ee_len + ext2_ee_len > EXT_MAX_LEN) return 0; #ifdef AGGRESSIVE_TEST if (le16_to_cpu(ex1->ee_len) >= 4) return 0; #endif - if (ext_pblock(ex1) + le16_to_cpu(ex1->ee_len) == ext_pblock(ex2)) + if (ext_pblock(ex1) + ext1_ee_len == ext_pblock(ex2)) return 1; return 0; } @@ -1144,7 +1157,7 @@ unsigned int ext4_ext_check_overlap(struct inode *inode, unsigned int ret = 0; b1 = le32_to_cpu(newext->ee_block); - len1 = le16_to_cpu(newext->ee_len); + len1 = ext4_ext_get_actual_len(newext); depth = ext_depth(inode); if (!path[depth].p_ext) goto out; @@ -1191,8 +1204,9 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, struct ext4_extent *nearex; /* nearest extent */ struct ext4_ext_path *npath = NULL; int depth, len, err, next; + unsigned uninitialized = 0; - BUG_ON(newext->ee_len == 0); + BUG_ON(ext4_ext_get_actual_len(newext) == 0); depth = ext_depth(inode); ex = path[depth].p_ext; BUG_ON(path[depth].p_hdr == NULL); @@ -1200,14 +1214,24 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, /* try to insert block into found extent and return */ if (ex && ext4_can_extents_be_merged(inode, ex, newext)) { ext_debug("append %d block to %d:%d (from %llu)\n", - le16_to_cpu(newext->ee_len), + ext4_ext_get_actual_len(newext), le32_to_cpu(ex->ee_block), - le16_to_cpu(ex->ee_len), ext_pblock(ex)); + ext4_ext_get_actual_len(ex), ext_pblock(ex)); err = ext4_ext_get_access(handle, inode, path + depth); if (err) return err; - ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len) - + le16_to_cpu(newext->ee_len)); + + /* + * ext4_can_extents_be_merged should have checked that either + * both extents are uninitialized, or both aren't. Thus we + * need to check only one of them here. + */ + if (ext4_ext_is_uninitialized(ex)) + uninitialized = 1; + ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) + + ext4_ext_get_actual_len(newext)); + if (uninitialized) + ext4_ext_mark_uninitialized(ex); eh = path[depth].p_hdr; nearex = ex; goto merge; @@ -1263,7 +1287,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, ext_debug("first extent in the leaf: %d:%llu:%d\n", le32_to_cpu(newext->ee_block), ext_pblock(newext), - le16_to_cpu(newext->ee_len)); + ext4_ext_get_actual_len(newext)); path[depth].p_ext = EXT_FIRST_EXTENT(eh); } else if (le32_to_cpu(newext->ee_block) > le32_to_cpu(nearex->ee_block)) { @@ -1276,7 +1300,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, "move %d from 0x%p to 0x%p\n", le32_to_cpu(newext->ee_block), ext_pblock(newext), - le16_to_cpu(newext->ee_len), + ext4_ext_get_actual_len(newext), nearex, len, nearex + 1, nearex + 2); memmove(nearex + 2, nearex + 1, len); } @@ -1289,7 +1313,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, "move %d from 0x%p to 0x%p\n", le32_to_cpu(newext->ee_block), ext_pblock(newext), - le16_to_cpu(newext->ee_len), + ext4_ext_get_actual_len(newext), nearex, len, nearex + 1, nearex + 2); memmove(nearex + 1, nearex, len); path[depth].p_ext = nearex; @@ -1308,8 +1332,13 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1)) break; /* merge with next extent! */ - nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len) - + le16_to_cpu(nearex[1].ee_len)); + if (ext4_ext_is_uninitialized(nearex)) + uninitialized = 1; + nearex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(nearex) + + ext4_ext_get_actual_len(nearex + 1)); + if (uninitialized) + ext4_ext_mark_uninitialized(nearex); + if (nearex + 1 < EXT_LAST_EXTENT(eh)) { len = (EXT_LAST_EXTENT(eh) - nearex - 1) * sizeof(struct ext4_extent); @@ -1379,8 +1408,8 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block, end = le32_to_cpu(ex->ee_block); if (block + num < end) end = block + num; - } else if (block >= - le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) { + } 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; @@ -1392,7 +1421,8 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block, * by found extent */ start = block; - end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len); + end = le32_to_cpu(ex->ee_block) + + ext4_ext_get_actual_len(ex); if (block + num < end) end = block + num; exists = 1; @@ -1408,7 +1438,7 @@ int ext4_ext_walk_space(struct inode *inode, unsigned long block, cbex.ec_type = EXT4_EXT_CACHE_GAP; } else { cbex.ec_block = le32_to_cpu(ex->ee_block); - cbex.ec_len = le16_to_cpu(ex->ee_len); + cbex.ec_len = ext4_ext_get_actual_len(ex); cbex.ec_start = ext_pblock(ex); cbex.ec_type = EXT4_EXT_CACHE_EXTENT; } @@ -1481,15 +1511,15 @@ ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path, ext_debug("cache gap(before): %lu [%lu:%lu]", (unsigned long) block, (unsigned long) le32_to_cpu(ex->ee_block), - (unsigned long) le16_to_cpu(ex->ee_len)); + (unsigned long) ext4_ext_get_actual_len(ex)); } else if (block >= le32_to_cpu(ex->ee_block) - + le16_to_cpu(ex->ee_len)) { + + ext4_ext_get_actual_len(ex)) { lblock = le32_to_cpu(ex->ee_block) - + le16_to_cpu(ex->ee_len); + + ext4_ext_get_actual_len(ex); len = ext4_ext_next_allocated_block(path); ext_debug("cache gap(after): [%lu:%lu] %lu", (unsigned long) le32_to_cpu(ex->ee_block), - (unsigned long) le16_to_cpu(ex->ee_len), + (unsigned long) ext4_ext_get_actual_len(ex), (unsigned long) block); BUG_ON(len == lblock); len = len - lblock; @@ -1619,12 +1649,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, unsigned long from, unsigned long to) { struct buffer_head *bh; + unsigned short ee_len = ext4_ext_get_actual_len(ex); int i; #ifdef EXTENTS_STATS { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); - unsigned short ee_len = le16_to_cpu(ex->ee_len); spin_lock(&sbi->s_ext_stats_lock); sbi->s_ext_blocks += ee_len; sbi->s_ext_extents++; @@ -1638,12 +1668,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, } #endif if (from >= le32_to_cpu(ex->ee_block) - && to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { + && to == le32_to_cpu(ex->ee_block) + ee_len - 1) { /* tail removal */ unsigned long num; ext4_fsblk_t start; - num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from; - start = ext_pblock(ex) + le16_to_cpu(ex->ee_len) - num; + num = le32_to_cpu(ex->ee_block) + ee_len - from; + start = ext_pblock(ex) + ee_len - num; ext_debug("free last %lu blocks starting %llu\n", num, start); for (i = 0; i < num; i++) { bh = sb_find_get_block(inode->i_sb, start + i); @@ -1651,12 +1681,12 @@ static int ext4_remove_blocks(handle_t *handle, struct inode *inode, } ext4_free_blocks(handle, inode, start, num); } else if (from == le32_to_cpu(ex->ee_block) - && to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) { + && to <= le32_to_cpu(ex->ee_block) + ee_len - 1) { printk("strange request: removal %lu-%lu from %u:%u\n", - from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); + from, to, le32_to_cpu(ex->ee_block), ee_len); } else { printk("strange request: removal(2) %lu-%lu from %u:%u\n", - from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len)); + from, to, le32_to_cpu(ex->ee_block), ee_len); } return 0; } @@ -1671,6 +1701,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, unsigned a, b, block, num; unsigned long ex_ee_block; unsigned short ex_ee_len; + unsigned uninitialized = 0; struct ext4_extent *ex; ext_debug("truncate since %lu in leaf\n", start); @@ -1685,7 +1716,9 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, ex = EXT_LAST_EXTENT(eh); ex_ee_block = le32_to_cpu(ex->ee_block); - ex_ee_len = le16_to_cpu(ex->ee_len); + if (ext4_ext_is_uninitialized(ex)) + uninitialized = 1; + ex_ee_len = ext4_ext_get_actual_len(ex); while (ex >= EXT_FIRST_EXTENT(eh) && ex_ee_block + ex_ee_len > start) { @@ -1753,6 +1786,8 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, ex->ee_block = cpu_to_le32(block); ex->ee_len = cpu_to_le16(num); + if (uninitialized) + ext4_ext_mark_uninitialized(ex); err = ext4_ext_dirty(handle, inode, path + depth); if (err) @@ -1762,7 +1797,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, ext_pblock(ex)); ex--; ex_ee_block = le32_to_cpu(ex->ee_block); - ex_ee_len = le16_to_cpu(ex->ee_len); + ex_ee_len = ext4_ext_get_actual_len(ex); } if (correct_index && eh->eh_entries) @@ -2038,7 +2073,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, if (ex) { unsigned long ee_block = le32_to_cpu(ex->ee_block); ext4_fsblk_t ee_start = ext_pblock(ex); - unsigned short ee_len = le16_to_cpu(ex->ee_len); + unsigned short ee_len; /* * Allow future support for preallocated extents to be added @@ -2046,8 +2081,9 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, * Uninitialized extents are treated as holes, except that * we avoid (fail) allocating new blocks during a write. */ - if (ee_len > EXT_MAX_LEN) + if (le16_to_cpu(ex->ee_len) > EXT_MAX_LEN) goto out2; + ee_len = ext4_ext_get_actual_len(ex); /* if found extent covers block, simply return it */ if (iblock >= ee_block && iblock < ee_block + ee_len) { newblock = iblock - ee_block + ee_start; @@ -2055,8 +2091,11 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, allocated = ee_len - (iblock - ee_block); ext_debug("%d fit into %lu:%d -> %llu\n", (int) iblock, ee_block, ee_len, newblock); - ext4_ext_put_in_cache(inode, ee_block, ee_len, - ee_start, EXT4_EXT_CACHE_EXTENT); + /* Do not put uninitialized extent in the cache */ + if (!ext4_ext_is_uninitialized(ex)) + ext4_ext_put_in_cache(inode, ee_block, + ee_len, ee_start, + EXT4_EXT_CACHE_EXTENT); goto out; } } @@ -2098,6 +2137,8 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, /* try to insert new extent into found leaf and return */ ext4_ext_store_pblock(&newex, newblock); newex.ee_len = cpu_to_le16(allocated); + if (create == EXT4_CREATE_UNINITIALIZED_EXT) /* Mark uninitialized */ + ext4_ext_mark_uninitialized(&newex); err = ext4_ext_insert_extent(handle, inode, path, &newex); if (err) { /* free data blocks we just allocated */ @@ -2113,8 +2154,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, newblock = ext_pblock(&newex); __set_bit(BH_New, &bh_result->b_state); - ext4_ext_put_in_cache(inode, iblock, allocated, newblock, - EXT4_EXT_CACHE_EXTENT); + /* Cache only when it is _not_ an uninitialized extent */ + if (create != EXT4_CREATE_UNINITIALIZED_EXT) + ext4_ext_put_in_cache(inode, iblock, allocated, newblock, + EXT4_EXT_CACHE_EXTENT); out: if (allocated > max_blocks) allocated = max_blocks; @@ -2217,3 +2260,127 @@ int ext4_ext_writepage_trans_blocks(struct inode *inode, int num) return needed; } + +/* + * preallocate space for a file. This implements ext4's fallocate inode + * operation, which gets called from sys_fallocate system call. + * For block-mapped files, posix_fallocate should fall back to the method + * of writing zeroes to the required new blocks (the same behavior which is + * expected for file systems which do not support fallocate() system call). + */ +long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) +{ + handle_t *handle; + ext4_fsblk_t block, max_blocks; + ext4_fsblk_t nblocks = 0; + int ret = 0; + int ret2 = 0; + int retries = 0; + struct buffer_head map_bh; + unsigned int credits, blkbits = inode->i_blkbits; + + /* + * currently supporting (pre)allocate mode for extent-based + * files _only_ + */ + if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) + return -EOPNOTSUPP; + + /* preallocation to directories is currently not supported */ + if (S_ISDIR(inode->i_mode)) + return -ENODEV; + + block = offset >> blkbits; + 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 = EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + 3; +retry: + while (ret >= 0 && ret < max_blocks) { + block = block + ret; + max_blocks = max_blocks - ret; + handle = ext4_journal_start(inode, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + break; + } + + ret = ext4_ext_get_blocks(handle, inode, block, + max_blocks, &map_bh, + EXT4_CREATE_UNINITIALIZED_EXT, 0); + WARN_ON(!ret); + if (!ret) { + ext4_error(inode->i_sb, "ext4_fallocate", + "ext4_ext_get_blocks returned 0! inode#%lu" + ", block=%llu, max_blocks=%llu", + inode->i_ino, block, max_blocks); + ret = -EIO; + ext4_mark_inode_dirty(handle, inode); + ret2 = ext4_journal_stop(handle); + break; + } + if (ret > 0) { + /* check wrap through sign-bit/zero here */ + if ((block + ret) < 0 || (block + ret) < block) { + ret = -EIO; + ext4_mark_inode_dirty(handle, inode); + ret2 = ext4_journal_stop(handle); + break; + } + if (buffer_new(&map_bh) && ((block + ret) > + (EXT4_BLOCK_ALIGN(i_size_read(inode), blkbits) + >> blkbits))) + nblocks = nblocks + ret; + } + + /* Update ctime if new blocks get allocated */ + if (nblocks) { + struct timespec now; + + now = current_fs_time(inode->i_sb); + if (!timespec_equal(&inode->i_ctime, &now)) + inode->i_ctime = now; + } + + ext4_mark_inode_dirty(handle, inode); + ret2 = ext4_journal_stop(handle); + if (ret2) + break; + } + + if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) + goto retry; + + /* + * Time to update the file size. + * Update only when preallocation was requested beyond the file size. + */ + if (!(mode & FALLOC_FL_KEEP_SIZE) && + (offset + len) > i_size_read(inode)) { + if (ret > 0) { + /* + * if no error, we assume preallocation succeeded + * completely + */ + mutex_lock(&inode->i_mutex); + i_size_write(inode, offset + len); + EXT4_I(inode)->i_disksize = i_size_read(inode); + mutex_unlock(&inode->i_mutex); + } else if (ret < 0 && nblocks) { + /* Handle partial allocation scenario */ + loff_t newsize; + + mutex_lock(&inode->i_mutex); + newsize = (nblocks << blkbits) + i_size_read(inode); + i_size_write(inode, EXT4_BLOCK_ALIGN(newsize, blkbits)); + EXT4_I(inode)->i_disksize = i_size_read(inode); + mutex_unlock(&inode->i_mutex); + } + } + + return ret > 0 ? ret2 : ret; +} diff --git a/fs/ext4/file.c b/fs/ext4/file.c index d4c8186aed646f6a4439b17d0b0cda9655aadf55..1a81cd66d63b2b2371e4c35025f004657ca66adf 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -134,5 +134,6 @@ const struct inode_operations ext4_file_inode_operations = { .removexattr = generic_removexattr, #endif .permission = ext4_permission, + .fallocate = ext4_fallocate, }; diff --git a/include/linux/ext4_fs.h b/include/linux/ext4_fs.h index de1f9f78625a3279bf5ddb580d57cc1003eef152..87c2d7a05b01af12cd2da161d4db81f387e479c5 100644 --- a/include/linux/ext4_fs.h +++ b/include/linux/ext4_fs.h @@ -102,6 +102,7 @@ EXT4_GOOD_OLD_FIRST_INO : \ (s)->s_first_ino) #endif +#define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits))) /* * Macro-instructions used to manage fragments @@ -225,6 +226,11 @@ struct ext4_new_group_data { __u32 free_blocks_count; }; +/* + * Following is used by preallocation code to tell get_blocks() that we + * want uninitialzed extents. + */ +#define EXT4_CREATE_UNINITIALIZED_EXT 2 /* * ioctl commands @@ -983,6 +989,8 @@ extern int ext4_ext_get_blocks(handle_t *handle, struct inode *inode, extern void ext4_ext_truncate(struct inode *, struct page *); extern void ext4_ext_init(struct super_block *); extern void ext4_ext_release(struct super_block *); +extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset, + loff_t len); static inline int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block, unsigned long max_blocks, struct buffer_head *bh, diff --git a/include/linux/ext4_fs_extents.h b/include/linux/ext4_fs_extents.h index acfe59740b032d1a5adcfebaa69ca491c048cafa..e3d5afc6f23e00e0e65feb5310a0a8e79aa9f8ad 100644 --- a/include/linux/ext4_fs_extents.h +++ b/include/linux/ext4_fs_extents.h @@ -188,6 +188,21 @@ ext4_ext_invalidate_cache(struct inode *inode) EXT4_I(inode)->i_cached_extent.ec_type = EXT4_EXT_CACHE_NO; } +static inline void ext4_ext_mark_uninitialized(struct ext4_extent *ext) +{ + ext->ee_len |= cpu_to_le16(0x8000); +} + +static inline int ext4_ext_is_uninitialized(struct ext4_extent *ext) +{ + return (int)(le16_to_cpu((ext)->ee_len) & 0x8000); +} + +static inline int ext4_ext_get_actual_len(struct ext4_extent *ext) +{ + return (int)(le16_to_cpu((ext)->ee_len) & 0x7FFF); +} + extern int ext4_extent_tree_init(handle_t *, struct inode *); extern int ext4_ext_calc_credits_for_insert(struct inode *, struct ext4_ext_path *); extern unsigned int ext4_ext_check_overlap(struct inode *, struct ext4_extent *, struct ext4_ext_path *);