kernel/git/stable/linux.git/fs/ext4/file.c, branch linux-4.13.y

ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets

2017-09-27T12:43:14+00:00

commit 1bd8d6cd3e413d64e543ec3e69ff43e75a1cf1ea upstream. In the ext4 implementations of SEEK_HOLE and SEEK_DATA, make sure we return -ENXIO for negative offsets instead of banging around inside the extent code and returning -EFSCORRUPTED. Reported-by: Mateusz S Signed-off-by: Darrick J. Wong Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman

ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize

2017-08-05T21:43:24+00:00

ext4_find_unwritten_pgoff() does not properly handle a situation when starting index is in the middle of a page and blocksize < pagesize. The following command shows the bug on filesystem with 1k blocksize: xfs_io -f -c "falloc 0 4k" \ -c "pwrite 1k 1k" \ -c "pwrite 3k 1k" \ -c "seek -a -r 0" foo In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048, SEEK_DATA) will return the correct result. Fix the problem by neglecting buffers in a page before starting offset. Reported-by: Andreas Gruenbacher Signed-off-by: Theodore Ts'o Signed-off-by: Jan Kara CC: stable@vger.kernel.org # 3.8+

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2017-07-09T16:31:22+00:00

Pull ext4 updates from Ted Ts'o: "The first major feature for ext4 this merge window is the largedir feature, which allows ext4 directories to support over 2 billion directory entries (assuming ~64 byte file names; in practice, users will run into practical performance limits first.) This feature was originally written by the Lustre team, and credit goes to Artem Blagodarenko from Seagate for getting this feature upstream. The second major major feature allows ext4 to support extended attribute values up to 64k. This feature was also originally from Lustre, and has been enhanced by Tahsin Erdogan from Google with a deduplication feature so that if multiple files have the same xattr value (for example, Windows ACL's stored by Samba), only one copy will be stored on disk for encoding and caching efficiency. We also have the usual set of bug fixes, cleanups, and optimizations" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits) ext4: fix spelling mistake: "prellocated" -> "preallocated" ext4: fix __ext4_new_inode() journal credits calculation ext4: skip ext4_init_security() and encryption on ea_inodes fs: generic_block_bmap(): initialize all of the fields in the temp bh ext4: change fast symlink test to not rely on i_blocks ext4: require key for truncate(2) of encrypted file ext4: don't bother checking for encryption key in ->mmap() ext4: check return value of kstrtoull correctly in reserved_clusters_store ext4: fix off-by-one fsmap error on 1k block filesystems ext4: return EFSBADCRC if a bad checksum error is found in ext4_find_entry() ext4: return EIO on read error in ext4_find_entry ext4: forbid encrypting root directory ext4: send parallel discards on commit completions ext4: avoid unnecessary stalls in ext4_evict_inode() ext4: add nombcache mount option ext4: strong binding of xattr inode references ext4: eliminate xattr entry e_hash recalculation for removes ext4: reserve space for xattr entries/names quota: add get_inode_usage callback to transfer multi-inode charges ext4: xattr inode deduplication ...

ext4: don't bother checking for encryption key in ->mmap()

2017-06-23T23:41:38+00:00

Since only an open file can be mmap'ed, and we only allow open()ing an encrypted file when its key is available, there is no need to check for the key again before permitting each mmap(). Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o

ext4: nowait aio support

2017-06-20T13:12:03+00:00

Return EAGAIN if any of the following checks fail for direct I/O: + i_rwsem is lockable + Writing beyond end of file (will trigger allocation) + Blocks are not allocated at the write location Signed-off-by: Goldwyn Rodrigues Reviewed-by: Jan Kara Signed-off-by: Jens Axboe

ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()

2017-05-24T22:02:20+00:00

ext4_find_unwritten_pgoff() is used to search for offset of hole or data in page range [index, end] (both inclusive), and the max number of pages to search should be at least one, if end == index. Otherwise the only page is missed and no hole or data is found, which is not correct. When block size is smaller than page size, this can be demonstrated by preallocating a file with size smaller than page size and writing data to the last block. E.g. run this xfs_io command on a 1k block size ext4 on x86_64 host. # xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \ -c "seek -d 0" /mnt/ext4/testfile wrote 1024/1024 bytes at offset 2048 1 KiB, 1 ops; 0.0000 sec (42.459 MiB/sec and 43478.2609 ops/sec) Whence Result DATA EOF Data at offset 2k was missed, and lseek(2) returned ENXIO. This is unconvered by generic/285 subtest 07 and 08 on ppc64 host, where pagesize is 64k. Because a recent change to generic/285 reduced the preallocated file size to smaller than 64k. Signed-off-by: Eryu Guan Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara

ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()

2017-05-22T02:34:23+00:00

There is an off-by-one error in loop termination conditions in ext4_find_unwritten_pgoff() since 'end' may index a page beyond end of desired range if 'endoff' is page aligned. It doesn't have any visible effects but still it is good to fix it. Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: fix SEEK_HOLE

2017-05-22T02:33:23+00:00

Currently, SEEK_HOLE implementation in ext4 may both return that there's a hole at some offset although that offset already has data and skip some holes during a search for the next hole. The first problem is demostrated by: xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "seek -h 0" file wrote 57344/57344 bytes at offset 0 56 KiB, 14 ops; 0.0000 sec (2.054 GiB/sec and 538461.5385 ops/sec) Whence Result HOLE 0 Where we can see that SEEK_HOLE wrongly returned offset 0 as containing a hole although we have written data there. The second problem can be demonstrated by: xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k" -c "seek -h 0" file wrote 57344/57344 bytes at offset 0 56 KiB, 14 ops; 0.0000 sec (1.978 GiB/sec and 518518.5185 ops/sec) wrote 8192/8192 bytes at offset 131072 8 KiB, 2 ops; 0.0000 sec (2 GiB/sec and 500000.0000 ops/sec) Whence Result HOLE 139264 Where we can see that hole at offsets 56k..128k has been ignored by the SEEK_HOLE call. The underlying problem is in the ext4_find_unwritten_pgoff() which is just buggy. In some cases it fails to update returned offset when it finds a hole (when no pages are found or when the first found page has higher index than expected), in some cases conditions for detecting hole are just missing (we fail to detect a situation where indices of returned pages are not contiguous). Fix ext4_find_unwritten_pgoff() to properly detect non-contiguous page indices and also handle all cases where we got less pages then expected in one place and handle it properly there. CC: stable@vger.kernel.org Fixes: c8c0df241cc2719b1262e627f999638411934f60 CC: Zheng Liu Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o

ext4: return to starting transaction in ext4_dax_huge_fault()

2017-05-12T22:57:16+00:00

DAX will return to locking exceptional entry before mapping blocks for a page fault to fix possible races with concurrent writes. To avoid lock inversion between exceptional entry lock and transaction start, start the transaction already in ext4_dax_huge_fault(). Fixes: 9f141d6ef6258a3a37a045842d9ba7e68f368956 Link: http://lkml.kernel.org/r/20170510085419.27601-4-jack@suse.cz Signed-off-by: Jan Kara Cc: Ross Zwisler Cc: Dan Williams Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ext4: Add statx support

2017-04-03T05:05:58+00:00

Return enhanced file attributes from the Ext4 filesystem. This includes the following: (1) The inode creation time (i_crtime) as stx_btime, setting STATX_BTIME. (2) Certain FS_xxx_FL flags are mapped to stx_attribute flags. This requires that all ext4 inodes have a getattr call, not just some of them, so to this end, split the ext4_getattr() function and only call part of it where appropriate. Example output: [root@andromeda ~]# touch foo [root@andromeda ~]# chattr +ai foo [root@andromeda ~]# /tmp/test-statx foo statx(foo) = 0 results=fff Size: 0 Blocks: 0 IO Block: 4096 regular file Device: 08:12 Inode: 2101950 Links: 1 Access: (0644/-rw-r--r--) Uid: 0 Gid: 0 Access: 2016-02-11 17:08:29.031795451+0000 Modify: 2016-02-11 17:08:29.031795451+0000 Change: 2016-02-11 17:11:11.987790114+0000 Birth: 2016-02-11 17:08:29.031795451+0000 Attributes: 0000000000000030 (-------- -------- -------- -------- -------- -------- -------- --ai----) Signed-off-by: David Howells Signed-off-by: Al Viro