[PATCH 5/6 v7] ext4: fix fsx truncate failure
From: Allison Henderson <hidden>
Date: 2011-08-31 00:25:26
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
While running extended fsx tests to verify the first two patches, a similar bug was also found in the truncate operation This bug happens because the truncate routine only zeros the unblock aligned portion of the last page. This means that the block aligned portions of the page appearing after i_size are left unzeroed, and the buffer heads still mapped. This bug is corrected by using ext4_discard_partial_page_buffers in the truncate routine to zero the partial page and unmap the buffer headers Signed-off-by: Allison Henderson <redacted> --- :100644 100644 007fb08... b6cb686... M fs/ext4/extents.c :100644 100644 0962642... 9ae1d44... M fs/ext4/indirect.c fs/ext4/extents.c | 14 ++++++++++++-- fs/ext4/indirect.c | 16 ++++++++++++++-- 2 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 007fb08..b6cb686 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c@@ -3649,6 +3649,7 @@ void ext4_ext_truncate(struct inode *inode) struct super_block *sb = inode->i_sb; ext4_lblk_t last_block; handle_t *handle; + loff_t page_len; int err = 0; /*
@@ -3665,8 +3666,17 @@ void ext4_ext_truncate(struct inode *inode) if (IS_ERR(handle)) return; - if (inode->i_size & (sb->s_blocksize - 1)) - ext4_block_truncate_page(handle, mapping, inode->i_size); + if (inode->i_size % PAGE_CACHE_SIZE != 0) { + + page_len = PAGE_CACHE_SIZE - + (inode->i_size & (PAGE_CACHE_SIZE - 1)); + + err = ext4_discard_partial_page_buffers(handle, + mapping, inode->i_size, page_len, 0); + + if (err) + goto out_stop; + } if (ext4_orphan_add(handle, inode)) goto out_stop;
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 0962642..9ae1d44 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c@@ -1343,7 +1343,9 @@ void ext4_ind_truncate(struct inode *inode) __le32 nr = 0; int n = 0; ext4_lblk_t last_block, max_block; + loff_t page_len; unsigned blocksize = inode->i_sb->s_blocksize; + int err; handle = start_transaction(inode); if (IS_ERR(handle))
@@ -1354,9 +1356,19 @@ void ext4_ind_truncate(struct inode *inode) max_block = (EXT4_SB(inode->i_sb)->s_bitmap_maxbytes + blocksize-1) >> EXT4_BLOCK_SIZE_BITS(inode->i_sb); - if (inode->i_size & (blocksize - 1)) - if (ext4_block_truncate_page(handle, mapping, inode->i_size)) + + if (inode->i_size % PAGE_CACHE_SIZE != 0) { + + page_len = PAGE_CACHE_SIZE - + (inode->i_size & (PAGE_CACHE_SIZE - 1)); + + err = ext4_discard_partial_page_buffers(handle, + mapping, inode->i_size, page_len, 0); + + if (err) goto out_stop; + } + if (last_block != max_block) { n = ext4_block_to_path(inode, last_block, offsets, NULL);
--
1.7.1