Joe Thornber [Mon, 26 Sep 2011 01:51:47 +0000 (11:51 +1000)]
Initial EXPERIMENTAL implementation of device-mapper thin provisioning
with snapshot support. The 'thin' target is used to create instances of
the virtual devices that are hosted in the 'thin-pool' target. The
thin-pool target provides data sharing among devices. This sharing is
made possible using the persistent-data library in the previous patch.
The main highlight of this implementation, compared to the previous
implementation of snapshots, is that it allows many virtual devices to
be stored on the same data volume, simplifying administration and
allowing sharing of data between volumes (thus reducing disk usage).
Another big feature is support for arbitrary depth of recursive
snapshots (snapshots of snapshots of snapshots ...). The previous
implementation of snapshots did this by chaining together lookup tables,
and so performance was O(depth). This new implementation uses a single
data structure so we don't get this degradation with depth.
For further information and examples of how to use this, please read
Documentation/device-mapper/thin-provisioning.txt
Signed-off-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch introduces dm_kcopyd_zero() to make it easy to use
kcopyd to write zeros into the requested areas instead
instead of copying. It is implemented by passing a NULL
copying source to dm_kcopyd_copy().
The forthcoming thin provisioning target uses this.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow QUEUE_FLAG_NONROT to propagate up the device stack if all
underlying devices are non-rotational. Tools like ureadahead will
schedule IOs differently based on the rotational flag.
With this patch, I see boot time go from 7.75 s to 7.46 s on my device.
Suggested-by: J. Richard Barnette <jrbarnette@chromium.org> Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: Neil Brown <neilb@suse.de> Cc: Jens Axboe <jaxboe@fusionio.com> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: dm-devel@redhat.com Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Milan Broz [Mon, 26 Sep 2011 01:51:41 +0000 (11:51 +1000)]
If optional discard support in dm-crypt is enabled, discards requests
bypass the crypt queue and blocks of the underlying device are discarded.
For the read path, discarded blocks are handled the same as normal
ciphertext blocks, thus decrypted.
So if the underlying device announces discarded regions return zeroes,
dm-crypt must disable this flag because after decryption there is just
random noise instead of zeroes.
Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix off-by-one error in validation of write_mostly.
The user-supplied value given for the 'write_mostly' argument must be an
index starting at 0. The validation of the supplied argument failed to
check for 'N' ('>' vs '>='), which would have caused an access beyond the
end of the array.
Reported-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Mon, 26 Sep 2011 01:51:40 +0000 (11:51 +1000)]
Commit a63a5cf (dm: improve block integrity support) introduced a
two-phase initialization of a DM device's integrity profile. This
patch avoids dereferencing a NULL 'template_disk' pointer in
blk_integrity_register() if there is an integrity profile mismatch in
dm_table_set_integrity().
This can occur if the integrity profiles for stacked devices in a DM
table are changed between the call to dm_table_prealloc_integrity() and
dm_table_set_integrity().
Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: stable@kernel.org # 2.6.39
When TOMOYO started using garbage collector at commit 847b173e "TOMOYO: Add
garbage collector.", we waited for close() before kfree(). Thus, elements to be
kfree()d were queued up using tomoyo_gc_list list.
But it turned out that tomoyo_element_linked_by_gc() tends to choke garbage
collector when certain pattern of entries are queued.
Since garbage collector is no longer waiting for close() since commit 2e503bbb
"TOMOYO: Fix lockdep warning.", we can remove tomoyo_gc_list list and
tomoyo_element_linked_by_gc() by doing sequential processing.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
Commit efe836ab "TOMOYO: Add built-in policy support." introduced
tomoyo_load_builtin_policy() but was by error called from nowhere.
Commit b22b8b9f "TOMOYO: Rename meminfo to stat and show more statistics."
introduced tomoyo_update_stat() but was by error not called from
tomoyo_assign_domain().
Also, mark tomoyo_io_printf() and tomoyo_path_permission() static functions,
as reported by "make namespacecheck".
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
Magnus Damm [Sun, 25 Sep 2011 21:20:49 +0000 (23:20 +0200)]
ARM: mach-shmobile: sh7372 A3SM support
This patch adds sh7372 A3SM power domain support.
The sh7372 A3SM hardware power domain contains the
ARM Cortex-A8 CPU Core including L2 cache. This
sleep mode can be seen as a one step deeper sleep
mode from the already existing Core Standby mode.
To wake up from A3SM sleep only a few wakeup sources
are supported - so the regular INTC controller will
not be able to help us unfortunately.
The code in this patch will enter A3SM sleep via the
regular Suspend-to-RAM interface in the case of only
wakeups supported by A3SM are enabled. If unsupported
wakeups are enabled then Core Standby will be used
instead.
Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>