The major new feature added in this update is Darrick J. Wong's
metadata checksum feature, which adds crc32 checksums to ext4's
metadata fields. There is also the usual set of cleanups and bug
fixes.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull Ext4 updates from Theodore Ts'o:
"The major new feature added in this update is Darrick J Wong's
metadata checksum feature, which adds crc32 checksums to ext4's
metadata fields.
There is also the usual set of cleanups and bug fixes."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits)
ext4: hole-punch use truncate_pagecache_range
jbd2: use kmem_cache_zalloc wrapper instead of flag
ext4: remove mb_groups before tearing down the buddy_cache
ext4: add ext4_mb_unload_buddy in the error path
ext4: don't trash state flags in EXT4_IOC_SETFLAGS
ext4: let getattr report the right blocks in delalloc+bigalloc
ext4: add missing save_error_info() to ext4_error()
ext4: add debugging trigger for ext4_error()
ext4: protect group inode free counting with group lock
ext4: use consistent ssize_t type in ext4_file_write()
ext4: fix format flag in ext4_ext_binsearch_idx()
ext4: cleanup in ext4_discard_allocated_blocks()
ext4: return ENOMEM when mounts fail due to lack of memory
ext4: remove redundundant "(char *) bh->b_data" casts
ext4: disallow hard-linked directory in ext4_lookup
ext4: fix potential integer overflow in alloc_flex_gd()
ext4: remove needs_recovery in ext4_mb_init()
ext4: force ro mount if ext4_setup_super() fails
ext4: fix potential NULL dereference in ext4_free_inodes_counts()
ext4/jbd2: add metadata checksumming to the list of supported features
...
The ext4_error() function is missing a call to save_error_info().
Since this is the function which marks the file system as containing
an error, this oversight (which was introduced in 2.6.36) is quite
significant, and should be backported to older stable kernels with
high urgency.
Reported-by: Ken Sumrall <ksumrall@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: ksumrall@google.com
Cc: stable@kernel.org
Make it easy to test whether or not the error handling subsystem in
ext4 is working correctly. This allows us to simulate an ext4_error()
by echoing a string to /sys/fs/ext4/<dev>/trigger_fs_error.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: ksumrall@google.com
needs_recovery in ext4_mb_init() is not used, remove it.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.ne.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If ext4_setup_super() fails i.e. due to a too-high revision,
the error is logged in dmesg but the fs is not mounted RO as
indicated.
Tested by:
# mkfs.ext4 -r 4 /dev/sdb6
# mount /dev/sdb6 /mnt/test
# dmesg | grep "too high"
[164919.759248] EXT4-fs (sdb6): revision level too high, forcing read-only mode
# grep sdb6 /proc/mounts
/dev/sdb6 /mnt/test2 ext4 rw,seclabel,relatime,data=ordered 0 0
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
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Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux
Pull writeback tree from Wu Fengguang:
"Mainly from Jan Kara to avoid iput() in the flusher threads."
* tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
writeback: Avoid iput() from flusher thread
vfs: Rename end_writeback() to clear_inode()
vfs: Move waiting for inode writeback from end_writeback() to evict_inode()
writeback: Refactor writeback_single_inode()
writeback: Remove wb->list_lock from writeback_single_inode()
writeback: Separate inode requeueing after writeback
writeback: Move I_DIRTY_PAGES handling
writeback: Move requeueing when I_SYNC set to writeback_sb_inodes()
writeback: Move clearing of I_SYNC into inode_sync_complete()
writeback: initialize global_dirty_limit
fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds
mm: page-writeback.c: local functions should not be exposed globally
Add in the necessary code so that journal clients can enable the new
journal checksumming features.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Pull ext2, ext3 and quota fixes from Jan Kara:
"Interesting bits are:
- removal of a special i_mutex locking subclass (I_MUTEX_QUOTA) since
quota code does not need i_mutex anymore in any unusual way.
- backport (from ext4) of a fix of a checkpointing bug (missing cache
flush) that could lead to fs corruption on power failure
The rest are just random small fixes & cleanups."
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
ext2: trivial fix to comment for ext2_free_blocks
ext2: remove the redundant comment for ext2_export_ops
ext3: return 32/64-bit dir name hash according to usage type
quota: Get rid of nested I_MUTEX_QUOTA locking subclass
quota: Use precomputed value of sb_dqopt in dquot_quota_sync
ext2: Remove i_mutex use from ext2_quota_write()
reiserfs: Remove i_mutex use from reiserfs_quota_write()
ext4: Remove i_mutex use from ext4_quota_write()
ext3: Remove i_mutex use from ext3_quota_write()
quota: Fix double lock in add_dquot_ref() with CONFIG_QUOTA_DEBUG
jbd: Write journal superblock with WRITE_FUA after checkpointing
jbd: protect all log tail updates with j_checkpoint_mutex
jbd: Split updating of journal superblock and marking journal empty
ext2: do not register write_super within VFS
ext2: Remove s_dirt handling
ext2: write superblock only once on unmount
ext3: update documentation with barrier=1 default
ext3: remove max_debt in find_group_orlov()
jbd: Refine commit writeout logic
Pull user namespace enhancements from Eric Biederman:
"This is a course correction for the user namespace, so that we can
reach an inexpensive, maintainable, and reasonably complete
implementation.
Highlights:
- Config guards make it impossible to enable the user namespace and
code that has not been converted to be user namespace safe.
- Use of the new kuid_t type ensures the if you somehow get past the
config guards the kernel will encounter type errors if you enable
user namespaces and attempt to compile in code whose permission
checks have not been updated to be user namespace safe.
- All uids from child user namespaces are mapped into the initial
user namespace before they are processed. Removing the need to add
an additional check to see if the user namespace of the compared
uids remains the same.
- With the user namespaces compiled out the performance is as good or
better than it is today.
- For most operations absolutely nothing changes performance or
operationally with the user namespace enabled.
- The worst case performance I could come up with was timing 1
billion cache cold stat operations with the user namespace code
enabled. This went from 156s to 164s on my laptop (or 156ns to
164ns per stat operation).
- (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
Most uid/gid setting system calls treat these value specially
anyway so attempting to use -1 as a uid would likely cause
entertaining failures in userspace.
- If setuid is called with a uid that can not be mapped setuid fails.
I have looked at sendmail, login, ssh and every other program I
could think of that would call setuid and they all check for and
handle the case where setuid fails.
- If stat or a similar system call is called from a context in which
we can not map a uid we lie and return overflowuid. The LFS
experience suggests not lying and returning an error code might be
better, but the historical precedent with uids is different and I
can not think of anything that would break by lying about a uid we
can't map.
- Capabilities are localized to the current user namespace making it
safe to give the initial user in a user namespace all capabilities.
My git tree covers all of the modifications needed to convert the core
kernel and enough changes to make a system bootable to runlevel 1."
Fix up trivial conflicts due to nearby independent changes in fs/stat.c
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
userns: Silence silly gcc warning.
cred: use correct cred accessor with regards to rcu read lock
userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
userns: Convert cgroup permission checks to use uid_eq
userns: Convert tmpfs to use kuid and kgid where appropriate
userns: Convert sysfs to use kgid/kuid where appropriate
userns: Convert sysctl permission checks to use kuid and kgids.
userns: Convert proc to use kuid/kgid where appropriate
userns: Convert ext4 to user kuid/kgid where appropriate
userns: Convert ext3 to use kuid/kgid where appropriate
userns: Convert ext2 to use kuid/kgid where appropriate.
userns: Convert devpts to use kuid/kgid where appropriate
userns: Convert binary formats to use kuid/kgid where appropriate
userns: Add negative depends on entries to avoid building code that is userns unsafe
userns: signal remove unnecessary map_cred_ns
userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
userns: Convert stat to return values mapped from kuids and kgids
userns: Convert user specfied uids and gids in chown into kuids and kgid
userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
...
Previously we were only enabling the 64-bit jbd2 feature if the number
of blocks in the file system was greater 2**32-1. The problem with
this is that it makes it harder to test the 64-bit journal code paths
with small file systems, since a small test file system would with the
64-bit ext4 feature enable would use a 64-bit file system on-disk data
structures, but use a 32-bit journal.
This would also cause problems when trying to do an online resize to
grow the filesystem above the 2**32-1 boundary. Fortunately the patch
to support online resize for 64-bit file systems hasn't been merged
yet, so this problem hasn't arisen in practice.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We don't need i_mutex in ext4_quota_write() because writes to quota file
are serialized by dqio_mutex anyway. Changes to quota files outside of quota
code are forbidded and enforced by NOATIME and IMMUTABLE bits.
Signed-off-by: Jan Kara <jack@suse.cz>
After we moved inode_sync_wait() from end_writeback() it doesn't make sense
to call the function end_writeback() anymore. Rename it to clear_inode()
which well says what the function really does - set I_CLEAR flag.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
metadata_csum supersedes uninit_bg. Convert the ROCOMPAT uninit_bg
flag check to a helper function that covers both, and make the
checksum calculation algorithm use either crc16 or the metadata_csum
chosen algorithm depending on which flag is set. Print a warning if
we try to mount a filesystem with both feature flags set.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Calculate and verify the superblock checksum. Since the UUID and
block group number are embedded in each copy of the superblock, we
need only checksum the entire block. Refactor some of the code to
eliminate open-coding of the checksum update call.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Obtain a reference to the cryptoapi and crc32c if we mount a
filesystem with metadata checksumming enabled.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Record the type of checksum algorithm we're using for metadata in the
superblock, in case we ever want/need to change the algorithm.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
sb info is only checked with quota support.
fs/ext4/super.c: In function ‘parse_options’:
fs/ext4/super.c:1600:23: warning: unused variable ‘sbi’ [-Wunused-variable]
Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit 26092bf5 broke handling of journalled quota mount options by
trying to parse argument of every mount option as a number. Fix this
by dealing with the quota options before we call match_int().
Thanks to Jan Kara for discovering this regression.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Andi Kleen and Tim Chen have reported that under certain circumstances
the extent cache statistics are causing scalability problems due to
cache line bounces.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
The changes to export dirty_writeback_interval are from Artem's s_dirt
cleanup patch series. The same is true of the change to remove the
s_dirt helper functions which never got used by anyone in-tree. I've
run these changes by Al Viro, and am carrying them so that Artem can
more easily fix up the rest of the file systems during the next merge
window. (Originally we had hopped to remove the use of s_dirt from
ext4 during this merge window, but his patches had some bugs, so I
ultimately ended dropping them from the ext4 tree.)
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates for 3.4 from Ted Ts'o:
"Ext4 commits for 3.3 merge window; mostly cleanups and bug fixes
The changes to export dirty_writeback_interval are from Artem's s_dirt
cleanup patch series. The same is true of the change to remove the
s_dirt helper functions which never got used by anyone in-tree. I've
run these changes by Al Viro, and am carrying them so that Artem can
more easily fix up the rest of the file systems during the next merge
window. (Originally we had hopped to remove the use of s_dirt from
ext4 during this merge window, but his patches had some bugs, so I
ultimately ended dropping them from the ext4 tree.)"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (66 commits)
vfs: remove unused superblock helpers
mm: export dirty_writeback_interval
ext4: remove useless s_dirt assignment
ext4: write superblock only once on unmount
ext4: do not mark superblock as dirty unnecessarily
ext4: correct ext4_punch_hole return codes
ext4: remove restrictive checks for EOFBLOCKS_FL
ext4: always set then trimmed blocks count into len
ext4: fix trimmed block count accunting
ext4: fix start and len arguments handling in ext4_trim_fs()
ext4: update s_free_{inodes,blocks}_count during online resize
ext4: change some printk() calls to use ext4_msg() instead
ext4: avoid output message interleaving in ext4_error_<foo>()
ext4: remove trailing newlines from ext4_msg() and ext4_error() messages
ext4: add no_printk argument validation, fix fallout
ext4: remove redundant "EXT4-fs: " from uses of ext4_msg
ext4: give more helpful error message in ext4_ext_rm_leaf()
ext4: remove unused code from ext4_ext_map_blocks()
ext4: rewrite punch hole to use ext4_ext_remove_space()
jbd2: cleanup journal tail after transaction commit
...
Clean-up ext4 a tiny bit by removing useless s_dirt assignment in
'ext4_fill_super()' because a bit later we anyway call
'ext4_setup_super()' which writes the superblock to the media
unconditionally.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In some rather rare cases it is possible that ext4 may the superblock
to the media twice. This patch makes sure this does not happen. This
should speed up unmounting in those cases.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Using KERN_CONT means that messages from multiple threads may be
interleaved. Avoid this by using a single printk call in
ext4_error_inode and ext4_error_file.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
No other file system allows ACL's and extended attributes to be
enabled or disabled via a mount option. So let's try to deprecate
these options from ext4.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Users who tried to use the ext4 file system driver is being used for
the ext2 or ext3 file systems (via the CONFIG_EXT4_USE_FOR_EXT23
option) could have failed mounts if their /etc/fstab contains options
recognized by ext2 or ext3 but which have since been removed in ext4.
So teach ext4 to recognize them and give a warning that the mount
option was removed.
Report: https://bbs.archlinux.org/profile.php?id=33804
Signed-off-by: Tom Gundersen <teg@jklm.no>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Baechler <thomas@archlinux.org>
Cc: Tobias Powalowski <tobias.powalowski@googlemail.com>
Cc: Dave Reisner <d@falconindy.com>
Now that /proc/mounts is consistently showing only those mount options
which need to be specified in /etc/fstab or on the mount command line,
it is useful to have file which shows exactly which file system
options are enabled. This can be useful when debugging a user
problem.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Consistently show mount options which are the non-default, so that
/proc/mounts accurately shows the mount options that would be
necessary to mount the file system in its current mode of operation.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is strictly a code movement so in preparation of changing
ext4_show_options to be table driven.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
By using a table-drive approach, we shave about 100 lines of code from
ext4, and make the code a bit more regular and factored out. This
will also make it possible in a future patch to use this table for
displaying the mount options that were specified in /proc/mounts.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There's no point to have two bits that are set in parallel; so use the
MS_I_VERSION flag that is needed by the VFS anyway, and that way we
free up a bit in sbi->s_mount_opts.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
People complained about removing both of these features, so per
Linus's dictate, we won't be able to remove them. Sigh...
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The resize mount option seems to be of limited value,
especially in the age of online resize2fs. Nuke it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The V2 journal format was introduced around ten years ago,
for ext3. It seems highly unlikely that anyone will need this
migration option for ext4.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The per-commit callback was used by mballoc code to manage free space
bitmaps after deleted blocks have been released. This patch expands
it to support multiple different callbacks, to allow other things to
be done after the commit has been completed.
Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Commit 503358ae01 ("ext4: avoid divide by
zero when trying to mount a corrupted file system") fixes CVE-2009-4307
by performing a sanity check on s_log_groups_per_flex, since it can be
set to a bogus value by an attacker.
sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
groups_per_flex = 1 << sbi->s_log_groups_per_flex;
if (groups_per_flex < 2) { ... }
This patch fixes two potential issues in the previous commit.
1) The sanity check might only work on architectures like PowerPC.
On x86, 5 bits are used for the shifting amount. That means, given a
large s_log_groups_per_flex value like 36, groups_per_flex = 1 << 36
is essentially 1 << 4 = 16, rather than 0. This will bypass the check,
leaving s_log_groups_per_flex and groups_per_flex inconsistent.
2) The sanity check relies on undefined behavior, i.e., oversized shift.
A standard-confirming C compiler could rewrite the check in unexpected
ways. Consider the following equivalent form, assuming groups_per_flex
is unsigned for simplicity.
groups_per_flex = 1 << sbi->s_log_groups_per_flex;
if (groups_per_flex == 0 || groups_per_flex == 1) {
We compile the code snippet using Clang 3.0 and GCC 4.6. Clang will
completely optimize away the check groups_per_flex == 0, leaving the
patched code as vulnerable as the original. GCC keeps the check, but
there is no guarantee that future versions will do the same.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
a) leaking root dentry is bad
b) in case of failed ext4_mb_init() we don't want to do ext4_mb_release()
c) OTOH, in the same case we *do* want ext4_ext_release()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
PM / Hibernate: Implement compat_ioctl for /dev/snapshot
PM / Freezer: fix return value of freezable_schedule_timeout_killable()
PM / shmobile: Allow the A4R domain to be turned off at run time
PM / input / touchscreen: Make st1232 use device PM QoS constraints
PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
PM / shmobile: Remove the stay_on flag from SH7372's PM domains
PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
PM: Drop generic_subsys_pm_ops
PM / Sleep: Remove forward-only callbacks from AMBA bus type
PM / Sleep: Remove forward-only callbacks from platform bus type
PM: Run the driver callback directly if the subsystem one is not there
PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.
PM / Sleep: Merge internal functions in generic_ops.c
PM / Sleep: Simplify generic system suspend callbacks
PM / Hibernate: Remove deprecated hibernation snapshot ioctls
PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
ARM: S3C64XX: Implement basic power domain support
PM / shmobile: Use common always on power domain governor
...
Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused
XBT_FORCE_SLEEP bit
Currently the value reported for max_batch_time is really the
value of min_batch_time.
Reported-by: Russell Coker <russell@coker.com.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
