Simplify ext4_collapse_range() and align its code style with that of ext4_zero_range() and ext4_punch_hole(). Refactor it by: a) renaming variables, b) removing redundant input parameter checks and moving the remaining checks under i_rwsem in preparation for future refactoring, and c) renaming the three stale error tags. Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx> --- fs/ext4/extents.c | 103 +++++++++++++++++++++------------------------- 1 file changed, 48 insertions(+), 55 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index f843342e5164..a4e95f3b5f09 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -5295,43 +5295,36 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len) struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; struct address_space *mapping = inode->i_mapping; - ext4_lblk_t punch_start, punch_stop; + loff_t end = offset + len; + ext4_lblk_t start_lblk, end_lblk; handle_t *handle; unsigned int credits; - loff_t new_size, ioffset; + loff_t start, new_size; int ret; - /* - * We need to test this early because xfstests assumes that a - * collapse range of (0, 1) will return EOPNOTSUPP if the file - * system does not support collapse range. - */ - if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) - return -EOPNOTSUPP; + trace_ext4_collapse_range(inode, offset, len); - /* Collapse range works only on fs cluster size aligned regions. */ - if (!IS_ALIGNED(offset | len, EXT4_CLUSTER_SIZE(sb))) - return -EINVAL; + inode_lock(inode); - trace_ext4_collapse_range(inode, offset, len); + /* Currently just for extent based files */ + if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { + ret = -EOPNOTSUPP; + goto out; + } - punch_start = offset >> EXT4_BLOCK_SIZE_BITS(sb); - punch_stop = (offset + len) >> EXT4_BLOCK_SIZE_BITS(sb); + /* Collapse range works only on fs cluster size aligned regions. */ + if (!IS_ALIGNED(offset | len, EXT4_CLUSTER_SIZE(sb))) { + ret = -EINVAL; + goto out; + } - inode_lock(inode); /* * There is no need to overlap collapse range with EOF, in which case * it is effectively a truncate operation */ - if (offset + len >= inode->i_size) { + if (end >= inode->i_size) { ret = -EINVAL; - goto out_mutex; - } - - /* Currently just for extent based files */ - if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { - ret = -EOPNOTSUPP; - goto out_mutex; + goto out; } /* Wait for existing dio to complete */ @@ -5339,7 +5332,7 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len) ret = file_modified(file); if (ret) - goto out_mutex; + goto out; /* * Prevent page faults from reinstantiating pages we have released from @@ -5349,55 +5342,52 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len) ret = ext4_break_layouts(inode); if (ret) - goto out_mmap; + goto out_invalidate_lock; /* + * Write tail of the last page before removed range and data that + * will be shifted since they will get removed from the page cache + * below. We are also protected from pages becoming dirty by + * i_rwsem and invalidate_lock. * Need to round down offset to be aligned with page size boundary * for page size > block size. */ - ioffset = round_down(offset, PAGE_SIZE); - /* - * Write tail of the last page before removed range since it will get - * removed from the page cache below. - */ - ret = filemap_write_and_wait_range(mapping, ioffset, offset); - if (ret) - goto out_mmap; - /* - * Write data that will be shifted to preserve them when discarding - * page cache below. We are also protected from pages becoming dirty - * by i_rwsem and invalidate_lock. - */ - ret = filemap_write_and_wait_range(mapping, offset + len, - LLONG_MAX); + start = round_down(offset, PAGE_SIZE); + ret = filemap_write_and_wait_range(mapping, start, offset); + if (!ret) + ret = filemap_write_and_wait_range(mapping, end, LLONG_MAX); if (ret) - goto out_mmap; - truncate_pagecache(inode, ioffset); + goto out_invalidate_lock; + + truncate_pagecache(inode, start); 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_mmap; + goto out_invalidate_lock; } ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_FALLOC_RANGE, handle); + start_lblk = offset >> inode->i_blkbits; + end_lblk = (offset + len) >> inode->i_blkbits; + down_write(&EXT4_I(inode)->i_data_sem); ext4_discard_preallocations(inode); - ext4_es_remove_extent(inode, punch_start, EXT_MAX_BLOCKS - punch_start); + ext4_es_remove_extent(inode, start_lblk, EXT_MAX_BLOCKS - start_lblk); - ret = ext4_ext_remove_space(inode, punch_start, punch_stop - 1); + ret = ext4_ext_remove_space(inode, start_lblk, end_lblk - 1); if (ret) { up_write(&EXT4_I(inode)->i_data_sem); - goto out_stop; + goto out_handle; } ext4_discard_preallocations(inode); - ret = ext4_ext_shift_extents(inode, handle, punch_stop, - punch_stop - punch_start, SHIFT_LEFT); + ret = ext4_ext_shift_extents(inode, handle, end_lblk, + end_lblk - start_lblk, SHIFT_LEFT); if (ret) { up_write(&EXT4_I(inode)->i_data_sem); - goto out_stop; + goto out_handle; } new_size = inode->i_size - len; @@ -5405,16 +5395,19 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len) EXT4_I(inode)->i_disksize = new_size; up_write(&EXT4_I(inode)->i_data_sem); - if (IS_SYNC(inode)) - ext4_handle_sync(handle); ret = ext4_mark_inode_dirty(handle, inode); + if (ret) + goto out_handle; + ext4_update_inode_fsync_trans(handle, inode, 1); + if (IS_SYNC(inode)) + ext4_handle_sync(handle); -out_stop: +out_handle: ext4_journal_stop(handle); -out_mmap: +out_invalidate_lock: filemap_invalidate_unlock(mapping); -out_mutex: +out: inode_unlock(inode); return ret; } -- 2.39.2