diff options
Diffstat (limited to 'fs/ext4/extents.c')
| -rw-r--r-- | fs/ext4/extents.c | 818 |
1 files changed, 706 insertions, 112 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 74bc2d5..82df3ce 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -37,7 +37,6 @@ #include <linux/quotaops.h> #include <linux/string.h> #include <linux/slab.h> -#include <linux/falloc.h> #include <asm/uaccess.h> #include <linux/fiemap.h> #include "ext4_jbd2.h" @@ -1691,7 +1690,7 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, * the extent that was written properly split out and conversion to * initialized is trivial. */ - if (ext4_ext_is_uninitialized(ex1) || ext4_ext_is_uninitialized(ex2)) + if (ext4_ext_is_uninitialized(ex1) != ext4_ext_is_uninitialized(ex2)) return 0; ext1_ee_len = ext4_ext_get_actual_len(ex1); @@ -1708,6 +1707,11 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1, */ if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN) return 0; + if (ext4_ext_is_uninitialized(ex1) && + (ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN) || + atomic_read(&EXT4_I(inode)->i_unwritten) || + (ext1_ee_len + ext2_ee_len > EXT_UNINIT_MAX_LEN))) + return 0; #ifdef AGGRESSIVE_TEST if (ext1_ee_len >= 4) return 0; @@ -1731,7 +1735,7 @@ static int ext4_ext_try_to_merge_right(struct inode *inode, { struct ext4_extent_header *eh; unsigned int depth, len; - int merge_done = 0; + int merge_done = 0, uninit; depth = ext_depth(inode); BUG_ON(path[depth].p_hdr == NULL); @@ -1741,8 +1745,11 @@ static int ext4_ext_try_to_merge_right(struct inode *inode, if (!ext4_can_extents_be_merged(inode, ex, ex + 1)) break; /* merge with next extent! */ + uninit = ext4_ext_is_uninitialized(ex); ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) + ext4_ext_get_actual_len(ex + 1)); + if (uninit) + ext4_ext_mark_uninitialized(ex); if (ex + 1 < EXT_LAST_EXTENT(eh)) { len = (EXT_LAST_EXTENT(eh) - ex - 1) @@ -1896,7 +1903,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, struct ext4_ext_path *npath = NULL; int depth, len, err; ext4_lblk_t next; - int mb_flags = 0; + int mb_flags = 0, uninit; if (unlikely(ext4_ext_get_actual_len(newext) == 0)) { EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0"); @@ -1946,9 +1953,11 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode, path + depth); if (err) return err; - + uninit = ext4_ext_is_uninitialized(ex); ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) + ext4_ext_get_actual_len(newext)); + if (uninit) + ext4_ext_mark_uninitialized(ex); eh = path[depth].p_hdr; nearex = ex; goto merge; @@ -1971,10 +1980,13 @@ prepend: if (err) return err; + uninit = ext4_ext_is_uninitialized(ex); ex->ee_block = newext->ee_block; ext4_ext_store_pblock(ex, ext4_ext_pblock(newext)); ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex) + ext4_ext_get_actual_len(newext)); + if (uninit) + ext4_ext_mark_uninitialized(ex); eh = path[depth].p_hdr; nearex = ex; goto merge; @@ -2585,6 +2597,27 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, ex_ee_block = le32_to_cpu(ex->ee_block); ex_ee_len = ext4_ext_get_actual_len(ex); + /* + * If we're starting with an extent other than the last one in the + * node, we need to see if it shares a cluster with the extent to + * the right (towards the end of the file). If its leftmost cluster + * is this extent's rightmost cluster and it is not cluster aligned, + * we'll mark it as a partial that is not to be deallocated. + */ + + if (ex != EXT_LAST_EXTENT(eh)) { + ext4_fsblk_t current_pblk, right_pblk; + long long current_cluster, right_cluster; + + current_pblk = ext4_ext_pblock(ex) + ex_ee_len - 1; + current_cluster = (long long)EXT4_B2C(sbi, current_pblk); + right_pblk = ext4_ext_pblock(ex + 1); + right_cluster = (long long)EXT4_B2C(sbi, right_pblk); + if (current_cluster == right_cluster && + EXT4_PBLK_COFF(sbi, right_pblk)) + *partial_cluster = -right_cluster; + } + trace_ext4_ext_rm_leaf(inode, start, ex, *partial_cluster); while (ex >= EXT_FIRST_EXTENT(eh) && @@ -2710,10 +2743,15 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, err = ext4_ext_correct_indexes(handle, inode, path); /* - * Free the partial cluster only if the current extent does not - * reference it. Otherwise we might free used cluster. + * If there's a partial cluster and at least one extent remains in + * the leaf, free the partial cluster if it isn't shared with the + * current extent. If there's a partial cluster and no extents + * remain in the leaf, it can't be freed here. It can only be + * freed when it's possible to determine if it's not shared with + * any other extent - when the next leaf is processed or when space + * removal is complete. */ - if (*partial_cluster > 0 && + if (*partial_cluster > 0 && eh->eh_entries && (EXT4_B2C(sbi, ext4_ext_pblock(ex) + ex_ee_len - 1) != *partial_cluster)) { int flags = get_default_free_blocks_flags(inode); @@ -3569,6 +3607,8 @@ out: * b> Splits in two extents: Write is happening at either end of the extent * c> Splits in three extents: Somone is writing in middle of the extent * + * This works the same way in the case of initialized -> unwritten conversion. + * * One of more index blocks maybe needed if the extent tree grow after * the uninitialized extent split. To prevent ENOSPC occur at the IO * complete, we need to split the uninitialized extent before DIO submit @@ -3579,7 +3619,7 @@ out: * * Returns the size of uninitialized extent to be written on success. */ -static int ext4_split_unwritten_extents(handle_t *handle, +static int ext4_split_convert_extents(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, struct ext4_ext_path *path, @@ -3591,9 +3631,9 @@ static int ext4_split_unwritten_extents(handle_t *handle, unsigned int ee_len; int split_flag = 0, depth; - ext_debug("ext4_split_unwritten_extents: inode %lu, logical" - "block %llu, max_blocks %u\n", inode->i_ino, - (unsigned long long)map->m_lblk, map->m_len); + ext_debug("%s: inode %lu, logical block %llu, max_blocks %u\n", + __func__, inode->i_ino, + (unsigned long long)map->m_lblk, map->m_len); eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits; @@ -3608,14 +3648,73 @@ static int ext4_split_unwritten_extents(handle_t *handle, ee_block = le32_to_cpu(ex->ee_block); ee_len = ext4_ext_get_actual_len(ex); - split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0; - split_flag |= EXT4_EXT_MARK_UNINIT2; - if (flags & EXT4_GET_BLOCKS_CONVERT) - split_flag |= EXT4_EXT_DATA_VALID2; + /* Convert to unwritten */ + if (flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN) { + split_flag |= EXT4_EXT_DATA_VALID1; + /* Convert to initialized */ + } else if (flags & EXT4_GET_BLOCKS_CONVERT) { + split_flag |= ee_block + ee_len <= eof_block ? + EXT4_EXT_MAY_ZEROOUT : 0; + split_flag |= (EXT4_EXT_MARK_UNINIT2 | EXT4_EXT_DATA_VALID2); + } flags |= EXT4_GET_BLOCKS_PRE_IO; return ext4_split_extent(handle, inode, path, map, split_flag, flags); } +static int ext4_convert_initialized_extents(handle_t *handle, + struct inode *inode, + struct ext4_map_blocks *map, + struct ext4_ext_path *path) +{ + struct ext4_extent *ex; + ext4_lblk_t ee_block; + unsigned int ee_len; + int depth; + int err = 0; + + depth = ext_depth(inode); + ex = path[depth].p_ext; + ee_block = le32_to_cpu(ex->ee_block); + ee_len = ext4_ext_get_actual_len(ex); + + ext_debug("%s: inode %lu, logical" + "block %llu, max_blocks %u\n", __func__, inode->i_ino, + (unsigned long long)ee_block, ee_len); + + if (ee_block != map->m_lblk || ee_len > map->m_len) { + err = ext4_split_convert_extents(handle, inode, map, path, + EXT4_GET_BLOCKS_CONVERT_UNWRITTEN); + if (err < 0) + goto out; + ext4_ext_drop_refs(path); + path = ext4_ext_find_extent(inode, map->m_lblk, path, 0); + if (IS_ERR(path)) { + err = PTR_ERR(path); + goto out; + } + depth = ext_depth(inode); + ex = path[depth].p_ext; + } + + err = ext4_ext_get_access(handle, inode, path + depth); + if (err) + goto out; + /* first mark the extent as uninitialized */ + ext4_ext_mark_uninitialized(ex); + + /* note: ext4_ext_correct_indexes() isn't needed here because + * borders are not changed + */ + ext4_ext_try_to_merge(handle, inode, path, ex); + + /* Mark modified extent as dirty */ + err = ext4_ext_dirty(handle, inode, path + path->p_depth); +out: + ext4_ext_show_leaf(inode, path); + return err; +} + + static int ext4_convert_unwritten_extents_endio(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, @@ -3649,8 +3748,8 @@ static int ext4_convert_unwritten_extents_endio(handle_t *handle, inode->i_ino, (unsigned long long)ee_block, ee_len, (unsigned long long)map->m_lblk, map->m_len); #endif - err = ext4_split_unwritten_extents(handle, inode, map, path, - EXT4_GET_BLOCKS_CONVERT); + err = ext4_split_convert_extents(handle, inode, map, path, + EXT4_GET_BLOCKS_CONVERT); if (err < 0) goto out; ext4_ext_drop_refs(path); @@ -3851,6 +3950,38 @@ get_reserved_cluster_alloc(struct inode *inode, ext4_lblk_t lblk_start, } static int +ext4_ext_convert_initialized_extent(handle_t *handle, struct inode *inode, + struct ext4_map_blocks *map, + struct ext4_ext_path *path, int flags, + unsigned int allocated, ext4_fsblk_t newblock) +{ + int ret = 0; + int err = 0; + + /* + * Make sure that the extent is no bigger than we support with + * uninitialized extent + */ + if (map->m_len > EXT_UNINIT_MAX_LEN) + map->m_len = EXT_UNINIT_MAX_LEN / 2; + + ret = ext4_convert_initialized_extents(handle, inode, map, + path); + if (ret >= 0) { + ext4_update_inode_fsync_trans(handle, inode, 1); + err = check_eofblocks_fl(handle, inode, map->m_lblk, + path, map->m_len); + } else + err = ret; + map->m_flags |= EXT4_MAP_UNWRITTEN; + if (allocated > map->m_len) + allocated = map->m_len; + map->m_len = allocated; + + return err ? err : allocated; +} + +static int ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, struct ext4_ext_path *path, int flags, @@ -3877,8 +4008,8 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode, /* get_block() before submit the IO, split the extent */ if ((flags & EXT4_GET_BLOCKS_PRE_IO)) { - ret = ext4_split_unwritten_extents(handle, inode, map, - path, flags); + ret = ext4_split_convert_extents(handle, inode, map, + path, flags | EXT4_GET_BLOCKS_CONVERT); if (ret <= 0) goto out; /* @@ -3993,10 +4124,6 @@ out1: map->m_pblk = newblock; map->m_len = allocated; out2: - if (path) { - ext4_ext_drop_refs(path); - kfree(path); - } return err ? err : allocated; } @@ -4128,7 +4255,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, struct ext4_extent newex, *ex, *ex2; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); ext4_fsblk_t newblock = 0; - int free_on_err = 0, err = 0, depth; + int free_on_err = 0, err = 0, depth, ret; unsigned int allocated = 0, offset = 0; unsigned int allocated_clusters = 0; struct ext4_allocation_request ar; @@ -4170,6 +4297,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ext4_fsblk_t ee_start = ext4_ext_pblock(ex); unsigned short ee_len; + /* * Uninitialized extents are treated as holes, except that * we split out initialized portions during a write. @@ -4186,13 +4314,27 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ext_debug("%u fit into %u:%d -> %llu\n", map->m_lblk, ee_block, ee_len, newblock); - if (!ext4_ext_is_uninitialized(ex)) + /* + * If the extent is initialized check whether the + * caller wants to convert it to unwritten. + */ + if ((!ext4_ext_is_uninitialized(ex)) && + (flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) { + allocated = ext4_ext_convert_initialized_extent( + handle, inode, map, path, flags, + allocated, newblock); + goto out2; + } else if (!ext4_ext_is_uninitialized(ex)) goto out; - allocated = ext4_ext_handle_uninitialized_extents( + ret = ext4_ext_handle_uninitialized_extents( handle, inode, map, path, flags, allocated, newblock); - goto out3; + if (ret < 0) + err = ret; + else + allocated = ret; + goto out2; } } @@ -4473,7 +4615,6 @@ out2: kfree(path); } -out3: trace_ext4_ext_map_blocks_exit(inode, flags, map, err ? err : allocated); ext4_es_lru_add(inode); @@ -4514,34 +4655,200 @@ retry: ext4_std_error(inode->i_sb, err); } -static void ext4_falloc_update_inode(struct inode *inode, - int mode, loff_t new_size, int update_ctime) +static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset, + ext4_lblk_t len, int flags, int mode) { - struct timespec now; + struct inode *inode = file_inode(file); + handle_t *handle; + int ret = 0; + int ret2 = 0; + int retries = 0; + struct ext4_map_blocks map; + unsigned int credits; - if (update_ctime) { - now = current_fs_time(inode->i_sb); - if (!timespec_equal(&inode->i_ctime, &now)) - inode->i_ctime = now; + map.m_lblk = offset; + /* + * Don't normalize the request if it can fit in one extent so + * that it doesn't get unnecessarily split into multiple + * extents. + */ + if (len <= EXT_UNINIT_MAX_LEN) + flags |= EXT4_GET_BLOCKS_NO_NORMALIZE; + + /* + * credits to insert 1 extent into extent tree + */ + credits = ext4_chunk_trans_blocks(inode, len); + +retry: + while (ret >= 0 && ret < len) { + map.m_lblk = map.m_lblk + ret; + map.m_len = len = len - ret; + handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, + credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + break; + } + ret = ext4_map_blocks(handle, inode, &map, flags); + if (ret <= 0) { + ext4_debug("inode #%lu: block %u: len %u: " + "ext4_ext_map_blocks returned %d", + inode->i_ino, map.m_lblk, + map.m_len, ret); + ext4_mark_inode_dirty(handle, inode); + ret2 = ext4_journal_stop(handle); + break; + } + ret2 = ext4_journal_stop(handle); + if (ret2) + break; + } + if (ret == -ENOSPC && + ext4_should_retry_alloc(inode->i_sb, &retries)) { + ret = 0; + goto retry; } + + return ret > 0 ? ret2 : ret; +} + +static long ext4_zero_range(struct file *file, loff_t offset, + loff_t len, int mode) +{ + struct inode *inode = file_inode(file); + handle_t *handle = NULL; + unsigned int max_blocks; + loff_t new_size = 0; + int ret = 0; + int flags; + int partial; + loff_t start, end; + ext4_lblk_t lblk; + struct address_space *mapping = inode->i_mapping; + unsigned int blkbits = inode->i_blkbits; + + trace_ext4_zero_range(inode, offset, len, mode); + + /* + * Write out all dirty pages to avoid race conditions + * Then release them. + */ + if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { + ret = filemap_write_and_wait_range(mapping, offset, + offset + len - 1); + if (ret) + return ret; + } + /* - * Update only when preallocation was requested beyond - * the file size. + * Round up offset. This is not fallocate, we neet to zero out + * blocks, so convert interior block aligned part of the range to + * unwritten and possibly manually zero out unaligned parts of the + * range. */ - if (!(mode & FALLOC_FL_KEEP_SIZE)) { + start = round_up(offset, 1 << blkbits); + end = round_down((offset + len), 1 << blkbits); + + if (start < offset || end > offset + len) + return -EINVAL; + partial = (offset + len) & ((1 << blkbits) - 1); + + lblk = start >> blkbits; + max_blocks = (end >> blkbits); + if (max_blocks < lblk) + max_blocks = 0; + else + max_blocks -= lblk; + + flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT | + EXT4_GET_BLOCKS_CONVERT_UNWRITTEN; + if (mode & FALLOC_FL_KEEP_SIZE) + flags |= EXT4_GET_BLOCKS_KEEP_SIZE; + + mutex_lock(&inode->i_mutex); + + /* + * Indirect files do not support unwritten extnets + */ + if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { + ret = -EOPNOTSUPP; + goto out_mutex; + } + + if (!(mode & FALLOC_FL_KEEP_SIZE) && + offset + len > i_size_read(inode)) { + new_size = offset + len; + ret = inode_newsize_ok(inode, new_size); + if (ret) + goto out_mutex; + /* + * If we have a partial block after EOF we have to allocate + * the entire block. + */ + if (partial) + max_blocks += 1; + } + + if (max_blocks > 0) { + + /* Now release the pages and zero block aligned part of pages*/ + truncate_pagecache_range(inode, start, end - 1); + + /* Wait all existing dio workers, newcomers will block on i_mutex */ + ext4_inode_block_unlocked_dio(inode); + inode_dio_wait(inode); + + /* + * Remove entire range from the extent status tree. + */ + ret = ext4_es_remove_extent(inode, lblk, max_blocks); + if (ret) + goto out_dio; + + ret = ext4_alloc_file_blocks(file, lblk, max_blocks, flags, + mode); + if (ret) + goto out_dio; + } + + handle = ext4_journal_start(inode, EXT4_HT_MISC, 4); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + ext4_std_error(inode->i_sb, ret); + goto out_dio; + } + + inode->i_mtime = inode->i_ctime = ext4_current_time(inode); + + if (new_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); } else { /* - * Mark that we allocate beyond EOF so the subsequent truncate - * can proceed even if the new size is the same as i_size. - */ - if (new_size > i_size_read(inode)) + * Mark that we allocate beyond EOF so the subsequent truncate + * can proceed even if the new size is the same as i_size. + */ + if ((offset + len) > i_size_read(inode)) ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS); } + ext4_mark_inode_dirty(handle, inode); + + /* Zero out partial block at the edges of the range */ + ret = ext4_zero_partial_blocks(handle, inode, offset, len); + + if (file->f_flags & O_SYNC) + ext4_handle_sync(handle); + + ext4_journal_stop(handle); +out_dio: + ext4_inode_resume_unlocked_dio(inode); +out_mutex: + mutex_unlock(&inode->i_mutex); + return ret; } /* @@ -4555,22 +4862,25 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) { struct inode *inode = file_inode(file); handle_t *handle; - loff_t new_size; + loff_t new_size = 0; unsigned int max_blocks; int ret = 0; - int ret2 = 0; - int retries = 0; int flags; - struct ext4_map_blocks map; - unsigned int credits, blkbits = inode->i_blkbits; + ext4_lblk_t lblk; + struct timespec tv; + unsigned int blkbits = inode->i_blkbits; /* Return error if mode is not supported */ - if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) + if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | + FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)) return -EOPNOTSUPP; if (mode & FALLOC_FL_PUNCH_HOLE) return ext4_punch_hole(inode, offset, len); + if (mode & FALLOC_FL_COLLAPSE_RANGE) + return ext4_collapse_range(inode, offset, len); + ret = ext4_convert_inline_data(inode); if (ret) return ret; @@ -4582,83 +4892,66 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) return -EOPNOTSUPP; + if (mode & FALLOC_FL_ZERO_RANGE) + return ext4_zero_range(file, offset, len, mode); + trace_ext4_fallocate_enter(inode, offset, len, mode); - map.m_lblk = offset >> blkbits; + lblk = offset >> blkbits; /* * We can't just convert len to max_blocks because * If blocksize = 4096 offset = 3072 and len = 2048 */ max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits) - - map.m_lblk; - /* - * credits to insert 1 extent into extent tree - */ - credits = ext4_chunk_trans_blocks(inode, max_blocks); - mutex_lock(&inode->i_mutex); - ret = inode_newsize_ok(inode, (len + offset)); - if (ret) { - mutex_unlock(&inode->i_mutex); - trace_ext4_fallocate_exit(inode, offset, max_blocks, ret); - return ret; - } + - lblk; + flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT; if (mode & FALLOC_FL_KEEP_SIZE) flags |= EXT4_GET_BLOCKS_KEEP_SIZE; - /* - * Don't normalize the request if it can fit in one extent so - * that it doesn't get unnecessarily split into multiple - * extents. - */ - if (len <= EXT_UNINIT_MAX_LEN << blkbits) - flags |= EXT4_GET_BLOCKS_NO_NORMALIZE; -retry: - while (ret >= 0 && ret < max_blocks) { - map.m_lblk = map.m_lblk + ret; - map.m_len = max_blocks = max_blocks - ret; - handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, - credits); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - break; - } - ret = ext4_map_blocks(handle, inode, &map, flags); - if (ret <= 0) { -#ifdef EXT4FS_DEBUG - ext4_warning(inode->i_sb, - "inode #%lu: block %u: len %u: " - "ext4_ext_map_blocks returned %d", - inode->i_ino, map.m_lblk, - map.m_len, ret); -#endif - ext4_mark_inode_dirty(handle, inode); - ret2 = ext4_journal_stop(handle); - break; - } - if ((map.m_lblk + ret) >= (EXT4_BLOCK_ALIGN(offset + len, - blkbits) >> blkbits)) - new_size = offset + len; - else - new_size = ((loff_t) map.m_lblk + ret) << blkbits; + mutex_lock(&inode->i_mutex); - ext4_falloc_update_inode(inode, mode, new_size, - (map.m_flags & EXT4_MAP_NEW)); - ext4_mark_inode_dirty(handle, inode); - if ((file->f_flags & O_SYNC) && ret >= max_blocks) - ext4_handle_sync(handle); - ret2 = ext4_journal_stop(handle); - if (ret2) - break; + if (!(mode & FALLOC_FL_KEEP_SIZE) && + offset + len > i_size_read(inode)) { + new_size = offset + len; + ret = inode_newsize_ok(inode, new_size); + if (ret) + goto out; } - if (ret == -ENOSPC && - ext4_should_retry_alloc(inode->i_sb, &retries)) { - ret = 0; - goto retry; + + ret = ext4_alloc_file_blocks(file, lblk, max_blocks, flags, mode); + if (ret) + goto out; + + handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); + if (IS_ERR(handle)) + goto out; + + tv = inode->i_ctime = ext4_current_time(inode); + + if (new_size) { + if (new_size > i_size_read(inode)) { + i_size_write(inode, new_size); + inode->i_mtime = tv; + } + if (new_size > EXT4_I(inode)->i_disksize) + ext4_update_i_disksize(inode, new_size); + } else { + /* + * Mark that we allocate beyond EOF so the subsequent truncate + * can proceed even if the new size is the same as i_size. + */ + if ((offset + len) > i_size_read(inode)) + ext4_set_inode_flag(inode, EXT4_INODE_EOFBLOCKS); } + ext4_mark_inode_dirty(handle, inode); + if (file->f_flags & O_SYNC) + ext4_handle_sync(handle); + + ext4_journal_stop(handle); +out: mutex_unlock(&inode->i_mutex); - trace_ext4_fallocate_exit(inode, offset, max_blocks, - ret > 0 ? ret2 : ret); - return ret > 0 ? ret2 : ret; + trace_ext4_fallocate_exit(inode, offset, max_blocks, ret); + return ret; } /* @@ -4869,3 +5162,304 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, ext4_es_lru_add(inode); return error; } + +/* + * ext4_access_path: + * Function to access the path buffer for marking it dirty. + * It also checks if there are sufficient credits left in the journal handle + * to update path. + */ +static int +ext4_access_path(handle_t *handle, struct inode *inode, + struct ext4_ext_path *path) +{ + int credits, err; + + if (!ext4_handle_valid(handle)) + return 0; + + /* + * Check if need to extend journal credits + * 3 for leaf, sb, and inode plus 2 (bmap and group + * descriptor) for each block group; assume two block + * groups + */ + if (handle->h_buffer_credits < 7) { + credits = ext4_writepage_trans_blocks(inode); + err = ext4_ext_truncate_extend_restart(handle, inode, credits); + /* EAGAIN is success */ + if (err && err != -EAGAIN) + return err; + } + + err = ext4_ext_get_access(handle, inode, path); + return err; +} + +/* + * ext4_ext_shift_path_extents: + * Shift the extents of a path structure lying between path[depth].p_ext + * and EXT_LAST_EXTENT(path[depth].p_hdr) downwards, by subtracting shift + * from starting block for each extent. + */ +static int +ext4_ext_shift_path_extents(struct ext4_ext_path *path, ext4_lblk_t shift, + struct inode *inode, handle_t *handle, + ext4_lblk_t *start) +{ + int depth, err = 0; + struct ext4_extent *ex_start, *ex_last; + bool update = 0; + depth = path->p_depth; + + while (depth >= 0) { + if (depth == path->p_depth) { + ex_start = path[depth].p_ext; + if (!ex_start) + return -EIO; + + ex_last = EXT_LAST_EXTENT(path[depth].p_hdr); + if (!ex_last) + return -EIO; + + err = ext4_access_path(handle, inode, path + depth); + if (err) + goto out; + + if (ex_start == EXT_FIRST_EXTENT(path[depth].p_hdr)) + update = 1; + + *start = ex_last->ee_block + + ext4_ext_get_actual_len(ex_last); + + while (ex_start <= ex_last) { + ex_start->ee_block -= shift; + if (ex_start > + EXT_FIRST_EXTENT(path[depth].p_hdr)) { + if (ext4_ext_try_to_merge_right(inode, + path, ex_start - 1)) + ex_last--; + } + ex_start++; + } + err = ext4_ext_dirty(handle, inode, path + depth); + if (err) + goto out; + + if (--depth < 0 || !update) + break; + } + + /* Update index too */ + err = ext4_access_path(handle, inode, path + depth); + if (err) + goto out; + + path[depth].p_idx->ei_block -= shift; + err = ext4_ext_dirty(handle, inode, path + depth); + if (err) + goto out; + + /* we are done if current index is not a starting index */ + if (path[depth].p_idx != EXT_FIRST_INDEX(path[depth].p_hdr)) + break; + + depth--; + } + +out: + return err; +} + +/* + * ext4_ext_shift_extents: + * All the extents which lies in the range from start to the last allocated + * block for the file are shifted downwards by shift blocks. + * On success, 0 is returned, error otherwise. + */ +static int +ext4_ext_shift_extents(struct inode *inode, handle_t *handle, + ext4_lblk_t start, ext4_lblk_t shift) +{ + struct ext4_ext_path *path; + int ret = 0, depth; + struct ext4_extent *extent; + ext4_lblk_t stop_block, current_block; + ext4_lblk_t ex_start, ex_end; + + /* Let path point to the last extent */ + path = ext4_ext_find_extent(inode, EXT_MAX_BLOCKS - 1, NULL, 0); + if (IS_ERR(path)) + return PTR_ERR(path); + + depth = path->p_depth; + extent = path[depth].p_ext; + if (!extent) { + ext4_ext_drop_refs(path); + kfree(path); + return ret; + } + + stop_block = extent->ee_block + ext4_ext_get_actual_len(extent); + ext4_ext_drop_refs(path); + kfree(path); + + /* Nothing to shift, if hole is at the end of file */ + if (start >= stop_block) + return ret; + + /* + * Don't start shifting extents until we make sure the hole is big + * enough to accomodate the shift. + */ + path = ext4_ext_find_extent(inode, start - 1, NULL, 0); + depth = path->p_depth; + extent = path[depth].p_ext; + ex_start = extent->ee_block; + ex_end = extent->ee_block + ext4_ext_get_actual_len(extent); + ext4_ext_drop_refs(path); + kfree(path); + + if ((start == ex_start && shift > ex_start) || + (shift > start - ex_end)) + return -EINVAL; + + /* Its safe to start updating extents */ + while (start < stop_block) { + path = ext4_ext_find_extent(inode, start, NULL, 0); + if (IS_ERR(path)) + return PTR_ERR(path); + depth = path->p_depth; + extent = path[depth].p_ext; + current_block = extent->ee_block; + if (start > current_block) { + /* Hole, move to the next extent */ + ret = mext_next_extent(inode, path, &extent); + if (ret != 0) { + ext4_ext_drop_refs(path); + kfree(path); + if (ret == 1) + ret = 0; + break; + } + } + ret = ext4_ext_shift_path_extents(path, shift, inode, + handle, &start); + ext4_ext_drop_refs(path); + kfree(path); + if (ret) + break; + } + + return ret; +} + +/* + * ext4_collapse_range: + * This implements the fallocate's collapse range functionality for ext4 + * Returns: 0 and non-zero on error. + */ +int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) +{ + struct super_block *sb = inode->i_sb; + ext4_lblk_t punch_start, punch_stop; + handle_t *handle; + unsigned int credits; + loff_t new_size; + int ret; + + BUG_ON(offset + len > i_size_read(inode)); + + /* Collapse range works only on fs block size aligned offsets. */ + if (offset & (EXT4_BLOCK_SIZE(sb) - 1) || + len & (EXT4_BLOCK_SIZE(sb) - 1)) + return -EINVAL; + + if (!S_ISREG(inode->i_mode)) + return -EOPNOTSUPP; + + trace_ext4_collapse_range(inode, offset, len); + + punch_start = offset >> EXT4_BLOCK_SIZE_BITS(sb); + punch_stop = (offset + len) >> EXT4_BLOCK_SIZE_BITS(sb); + + /* Write out all dirty pages */ + ret = filemap_write_and_wait_range(inode->i_mapping, offset, -1); + if (ret) + return ret; + + /* Take mutex lock */ + mutex_lock(&inode->i_mutex); + + /* It's not possible punch hole on append only file */ + if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) { + ret = -EPERM; + goto out_mutex; + } + + if (IS_SWAPFILE(inode)) { + ret = -ETXTBSY; + goto out_mutex; + } + + /* Currently just for extent based files */ + if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { + ret = -EOPNOTSUPP; + goto out_mutex; + } + + truncate_pagecache_range(inode, offset, -1); + + /* Wait for existing dio to complete */ + ext4_inode_block_unlocked_dio(inode); + inode_dio_wait(inode); + + credits = ext4_writepage_trans_blocks(inode); + handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + goto out_dio; + } + + down_write(&EXT4_I(inode)->i_data_sem); + ext4_discard_preallocations(inode); + + ret = ext4_es_remove_extent(inode, punch_start, + EXT_MAX_BLOCKS - punch_start - 1); + if (ret) { + up_write(&EXT4_I(inode)->i_data_sem); + goto out_stop; + } + + ret = ext4_ext_remove_space(inode, punch_start, punch_stop - 1); + if (ret) { + up_write(&EXT4_I(inode)->i_data_sem); + goto out_stop; + } + + ret = ext4_ext_shift_extents(inode, handle, punch_stop, + punch_stop - punch_start); + if (ret) { + up_write(&EXT4_I(inode)->i_data_sem); + goto out_stop; + } + + new_size = i_size_read(inode) - len; + truncate_setsize(inode, new_size); + EXT4_I(inode)->i_disksize = new_size; + + ext4_discard_preallocations(inode); + up_write(&EXT4_I(inode)->i_data_sem); + if (IS_SYNC(inode)) + ext4_handle_sync(handle); + inode->i_mtime = inode->i_ctime = ext4_current_time(inode); + ext4_mark_inode_dirty(handle, inode); + +out_stop: + ext4_journal_stop(handle); +out_dio: + ext4_inode_resume_unlocked_dio(inode); +out_mutex: + mutex_unlock(&inode->i_mutex); + return ret; +} |
