diff options
Diffstat (limited to 'fs/ext4/inode.c')
| -rw-r--r-- | fs/ext4/inode.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 1bd0bfa547f6..5cf82d03968c 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2124,15 +2124,29 @@ static int ext4_writepage(struct page *page, static int mpage_submit_page(struct mpage_da_data *mpd, struct page *page) { int len; - loff_t size = i_size_read(mpd->inode); + loff_t size; int err; BUG_ON(page->index != mpd->first_page); + clear_page_dirty_for_io(page); + /* + * We have to be very careful here! Nothing protects writeback path + * against i_size changes and the page can be writeably mapped into + * page tables. So an application can be growing i_size and writing + * data through mmap while writeback runs. clear_page_dirty_for_io() + * write-protects our page in page tables and the page cannot get + * written to again until we release page lock. So only after + * clear_page_dirty_for_io() we are safe to sample i_size for + * ext4_bio_write_page() to zero-out tail of the written page. We rely + * on the barrier provided by TestClearPageDirty in + * clear_page_dirty_for_io() to make sure i_size is really sampled only + * after page tables are updated. + */ + size = i_size_read(mpd->inode); if (page->index == size >> PAGE_SHIFT) len = size & ~PAGE_MASK; else len = PAGE_SIZE; - clear_page_dirty_for_io(page); err = ext4_bio_write_page(&mpd->io_submit, page, len, mpd->wbc, false); if (!err) mpd->wbc->nr_to_write--; @@ -3629,9 +3643,6 @@ static ssize_t ext4_direct_IO_write(struct kiocb *iocb, struct iov_iter *iter) get_block_func = ext4_dio_get_block_unwritten_async; dio_flags = DIO_LOCKING; } -#ifdef CONFIG_EXT4_FS_ENCRYPTION - BUG_ON(ext4_encrypted_inode(inode) && S_ISREG(inode->i_mode)); -#endif ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, iter, get_block_func, ext4_end_io_dio, NULL, dio_flags); @@ -3713,7 +3724,7 @@ static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) */ inode_lock_shared(inode); ret = filemap_write_and_wait_range(mapping, iocb->ki_pos, - iocb->ki_pos + count); + iocb->ki_pos + count - 1); if (ret) goto out_unlock; ret = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev, @@ -4207,6 +4218,8 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) inode->i_mtime = inode->i_ctime = current_time(inode); ext4_mark_inode_dirty(handle, inode); + if (ret >= 0) + ext4_update_inode_fsync_trans(handle, inode, 1); out_stop: ext4_journal_stop(handle); out_dio: @@ -5637,8 +5650,9 @@ static int ext4_expand_extra_isize(struct inode *inode, /* No extended attributes present */ if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) || header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { - memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, - new_extra_isize); + memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE + + EXT4_I(inode)->i_extra_isize, 0, + new_extra_isize - EXT4_I(inode)->i_extra_isize); EXT4_I(inode)->i_extra_isize = new_extra_isize; return 0; } |