Darrick J. Wong [Sun, 29 Apr 2012 22:45:10 +0000 (18:45 -0400)]
ext4: make block group checksums use metadata_csum algorithm
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>
Darrick J. Wong [Sun, 29 Apr 2012 22:43:10 +0000 (18:43 -0400)]
ext4: Calculate and verify checksums of extended attribute blocks
Calculate and verify the checksums of extended attribute blocks. This
only applies to separate EA blocks that are pointed to by
inode->i_file_acl (i.e. external EA blocks); the checksum lives in
the EA header.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong [Sun, 29 Apr 2012 22:41:10 +0000 (18:41 -0400)]
ext4: calculate and verify checksums of directory leaf blocks
Calculate and verify the checksums for directory leaf blocks
(i.e. blocks that only contain actual directory entries). The
checksum lives in what looks to be an unused directory entry with a 0
name_len at the end of the block. This scheme is not used for
internal htree nodes because the mechanism in place there only costs
one dx_entry, whereas the "empty" directory entry would cost two
dx_entries.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong [Sun, 29 Apr 2012 22:39:10 +0000 (18:39 -0400)]
ext4: Calculate and verify checksums for htree nodes
Calculate and verify the checksum for directory index tree (htree)
node blocks. The checksum is stored in the last 4 bytes of the htree
block and requires the dx_entry array to stop 1 dx_entry short of the
end of the block.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong [Sun, 29 Apr 2012 22:37:10 +0000 (18:37 -0400)]
ext4: verify and calculate checksums for extent tree blocks
Calculate and verify the checksum for each extent tree block. The
checksum is located in the space immediately after the last possible
ext4_extent in the block. The space is is typically the last 4-8
bytes in the block.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong [Sun, 29 Apr 2012 22:31:10 +0000 (18:31 -0400)]
ext4: calculate and verify inode checksums
This patch introduces to ext4 the ability to calculate and verify
inode checksums. This requires the use of a new ro compatibility flag
and some accompanying e2fsprogs patches to provide the relevant
features in tune2fs and e2fsck. The inode generation changes have
been integrated into this patch.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong [Sun, 29 Apr 2012 22:29:10 +0000 (18:29 -0400)]
ext4: calculate and verify superblock checksum
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>
Darrick J. Wong [Sun, 29 Apr 2012 22:21:10 +0000 (18:21 -0400)]
ext4: create a new BH_Verified flag to avoid unnecessary metadata validation
Create a new BH_Verified flag to indicate that we've verified all the
data in a buffer_head for correctness. This allows us to bypass
expensive verification steps when they are not necessary without
missing them when they are.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Merge tag 'pm-for-3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael J. Wysocki:
"Fix for an issue causing hibernation to hang on systems with highmem
(that practically means i386) due to broken memory management (bug
introduced in 3.2, so -stable material) and PM documentation update
making the freezer documentation follow the code again after some
recent updates."
* tag 'pm-for-3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / Freezer / Docs: Update documentation about freezing of tasks
PM / Hibernate: fix the number of pages used for hibernate/thaw buffering
PM / QoS: Create device constraints objects on notifier registration
The current behavior of dev_pm_qos_add_notifier() makes device PM QoS
notifiers less than useful. Namely, it silently returns success when
called before any PM QoS constraints are added for the device, so the
caller will assume that the notifier has been registered, but when
someone actually adds some nontrivial constraints for the device
eventually, the previous callers of dev_pm_qos_add_notifier()
will not know about that and their notifier routines will not be
executed (contrary to their expectations).
To address this problem make dev_pm_qos_add_notifier() create the
constraints object for the device if it is not present when the
routine is called.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by : markgross <markgross@thegnar.org>
PM / Runtime: Remove device fields related to suspend time, v2
After the previous changes in default_stop_ok() and
default_power_down_ok() for PM domains, there are two fields in
struct dev_pm_info that aren't necessary any more, suspend_time
and max_time_suspended_ns.
Remove those fields along with all of the code that accesses them,
which simplifies the runtime PM framework quite a bit.
PM / Domains: Rework default domain power off governor function, v2
The existing default domain power down governor function for PM
domains, default_power_down_ok(), is supposed to check whether or not
the PM QoS latency constraints of the devices in the domain will be
violated if the domain is turned off by pm_genpd_poweroff().
However, the computations carried out by it don't reflect the
definition of the PM QoS latency constrait in
Documentation/ABI/testing/sysfs-devices-power.
Make default_power_down_ok() follow the definition of the PM QoS
latency constrait. In particular, make it only take latencies into
account, because it doesn't matter how much time has elapsed since
the domain's devices were suspended for the computation.
Remove the break_even_ns and power_off_time fields from
struct generic_pm_domain, because they are not necessary any more.