diff options
| -rw-r--r-- | fs/xfs/xfs_aops.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 84e372596d56..91d77ac51bba 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -927,11 +927,26 @@ xfs_vm_writepage( end_index = offset >> PAGE_CACHE_SHIFT; last_index = (offset - 1) >> PAGE_CACHE_SHIFT; if (page->index >= end_index) { - if ((page->index >= end_index + 1) || - !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) { + unsigned offset_into_page = offset & (PAGE_CACHE_SIZE - 1); + + /* + * Just skip the page if it is fully outside i_size, e.g. due + * to a truncate operation that is in progress. + */ + if (page->index >= end_index + 1 || offset_into_page == 0) { unlock_page(page); return 0; } + + /* + * The page straddles i_size. It must be zeroed out on each + * and every writepage invocation because it may be mmapped. + * "A file is mapped in multiples of the page size. For a file + * that is not a multiple of the page size, the remaining + * memory is zeroed when mapped, and writes to that region are + * not written out to the file." + */ + zero_user_segment(page, offset_into_page, PAGE_CACHE_SIZE); } end_offset = min_t(unsigned long long, |