- 11 2月, 2015 1 次提交
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由 Keith Busch 提交于
A DM device must inherit the QUEUE_FLAG_SG_GAPS flags from its underlying block devices' request queues. This fixes problems when submitting cloned requests to multipathed devices requiring virtually contiguous buffers. Signed-off-by: NKeith Busch <keith.busch@intel.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 10 2月, 2015 2 次提交
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由 Mike Snitzer 提交于
Otherwise replacing the multipath target with the error target fails: device-mapper: ioctl: can't change device type after initial table load. The error target was mistakenly considered to be target type DM_TYPE_REQUEST_BASED rather than DM_TYPE_MQ_REQUEST_BASED even if the target it was to replace was of type DM_TYPE_MQ_REQUEST_BASED. Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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由 Mike Snitzer 提交于
For blk-mq request-based DM the responsibility of allocating a cloned request is transfered from DM core to the target type. Doing so enables the cloned request to be allocated from the appropriate blk-mq request_queue's pool (only the DM target, e.g. multipath, can know which block device to send a given cloned request to). Care was taken to preserve compatibility with old-style block request completion that requires request-based DM _not_ acquire the clone request's queue lock in the completion path. As such, there are now 2 different request-based DM target_type interfaces: 1) the original .map_rq() interface will continue to be used for non-blk-mq devices -- the preallocated clone request is passed in from DM core. 2) a new .clone_and_map_rq() and .release_clone_rq() will be used for blk-mq devices -- blk_get_request() and blk_put_request() are used respectively from these hooks. dm_table_set_type() was updated to detect if the request-based target is being stacked on blk-mq devices, if so DM_TYPE_MQ_REQUEST_BASED is set. DM core disallows switching the DM table's type after it is set. This means that there is no mixing of non-blk-mq and blk-mq devices within the same request-based DM table. [This patch was started by Keith and later heavily modified by Mike] Tested-by: NBart Van Assche <bvanassche@acm.org> Signed-off-by: NKeith Busch <keith.busch@intel.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 20 11月, 2014 1 次提交
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由 Mike Snitzer 提交于
The DM thin-pool target now must undo the changes performed during pool_presuspend() so introduce presuspend_undo hook in target_type. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Acked-by: NJoe Thornber <ejt@redhat.com>
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- 06 10月, 2014 1 次提交
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由 Benjamin Marzinski 提交于
Until this change, when loading a new DM table, DM core would re-open all of the devices in the DM table. Now, DM core will avoid redundant device opens (and closes when destroying the old table) if the old table already has a device open using the same mode. This is achieved by managing reference counts on the table_devices that DM core now stores in the mapped_device structure (rather than in the dm_table structure). So a mapped_device's active and inactive dm_tables' dm_dev lists now just point to the dm_devs stored in the mapped_device's table_devices list. This improvement in DM core's device reference counting has the side-effect of fixing a long-standing limitation of the multipath target: a DM multipath table couldn't include any paths that were unusable (failed). For example: if all paths have failed and you add a new, working, path to the table; you can't use it since the table load would fail due to it still containing failed paths. Now a re-load of a multipath table can include failed devices and when those devices become active again they can be used instantly. The device list code in dm.c isn't a straight copy/paste from the code in dm-table.c, but it's very close (aside from some variable renames). One subtle difference is that find_table_device for the tables_devices list will only match devices with the same name and mode. This is because we don't want to upgrade a device's mode in the active table when an inactive table is loaded. Access to the mapped_device structure's tables_devices list requires a mutex (tables_devices_lock), so that tables cannot be created and destroyed concurrently. Signed-off-by: NBenjamin Marzinski <bmarzins@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 11 8月, 2014 1 次提交
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由 Jeff Moyer 提交于
Commit 05f1dd53 ("block: add queue flag for disabling SG merging") introduced a new queue flag: QUEUE_FLAG_NO_SG_MERGE. This gets set by default in blk_mq_init_queue for mq-enabled devices. The effect of the flag is to bypass the SG segment merging. Instead, the bio->bi_vcnt is used as the number of hardware segments. With a device mapper target on top of a device with QUEUE_FLAG_NO_SG_MERGE set, we can end up sending down more segments than a driver is prepared to handle. I ran into this when backporting the virtio_blk mq support. It triggerred this BUG_ON, in virtio_queue_rq: BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems); The queue's max is set here: blk_queue_max_segments(q, vblk->sg_elems-2); Basically, what happens is that a bio is built up for the dm device (which does not have the QUEUE_FLAG_NO_SG_MERGE flag set) using bio_add_page. That path will call into __blk_recalc_rq_segments, so what you end up with is bi_phys_segments being much smaller than bi_vcnt (and bi_vcnt grows beyond the maximum sg elements). Then, when the bio is submitted, it gets cloned. When the cloned bio is submitted, it will end up in blk_recount_segments, here: if (test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags)) bio->bi_phys_segments = bio->bi_vcnt; and now we've set bio->bi_phys_segments to a number that is beyond what was registered as queue_max_segments by the driver. The right way to fix this is to propagate the queue flag up the stack. The rules for propagating the flag are simple: - if the flag is set for any underlying device, it must be set for the upper device - consequently, if the flag is not set for any underlying device, it should not be set for the upper device. Signed-off-by: NJeff Moyer <jmoyer@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 3.16+
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- 02 8月, 2014 1 次提交
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由 Mikulas Patocka 提交于
The function dm_table_supports_discards is only called from dm-table.c:dm_table_set_restrictions(). So move it above dm_table_set_restrictions and make it static. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 04 6月, 2014 1 次提交
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由 Mike Snitzer 提交于
There is no need for code other than DM core to use dm_set_device_limits so remove its EXPORT_SYMBOL_GPL. Also, cleanup a couple whitespace nits. Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 28 3月, 2014 2 次提交
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由 Mike Snitzer 提交于
Introduce dm_table_run_md_queue_async() to run the request_queue of the mapped_device associated with a request-based DM table. Also add dm_md_get_queue() wrapper to extract the request_queue from a mapped_device. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NHannes Reinecke <hare@suse.de> Reviewed-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
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由 Mikulas Patocka 提交于
Make the function dm_table_alloc_md_mempools static because it is not called from another file. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 07 1月, 2014 1 次提交
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由 Mikulas Patocka 提交于
A device mapper table is allocated in the following way: * The function dm_table_create is called, it gets the number of targets as an argument -- it allocates a targets array accordingly. * For each target, we call dm_table_add_target. If we add more targets than were specified in dm_table_create, the function dm_table_add_target reallocates the targets array. However, this reallocation code is wrong - it moves the targets array to a new location, while some target constructors hold pointers to the array in the old location. The following DM target drivers save the pointer to the target structure, so they corrupt memory if the target array is moved: multipath, raid, mirror, snapshot, stripe, switch, thin, verity. Under normal circumstances, the reallocation function is not called (because dm_table_create is called with the correct number of targets), so the buggy reallocation code is not used. Prior to the fix "dm table: fail dm_table_create on dm_round_up overflow", the reallocation code could only be used in case the user specifies too large a value in param->target_count, such as 0xffffffff. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 11 12月, 2013 1 次提交
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由 Mikulas Patocka 提交于
The dm_round_up function may overflow to zero. In this case, dm_table_create() must fail rather than go on to allocate an empty array with alloc_targets(). This fixes a possible memory corruption that could be caused by passing too large a number in "param->target_count". Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
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- 10 11月, 2013 1 次提交
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由 Mike Snitzer 提交于
If preresume fails it is worth logging an error given that a device is left suspended due to the failure. This change was motivated by local preresume error logging that was added to the cache target ("preresume failed"). Elevating this target-agnostic context for the where the target-specific error occurred relative to the DM core's callouts makes sense. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NJoe Thornber <ejt@redhat.com>
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- 01 11月, 2013 1 次提交
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由 Mikulas Patocka 提交于
dm-mpath and dm-thin must process messages even if some device is suspended, so we allocate argv buffer with GFP_NOIO. These messages have a small fixed number of arguments. On the other hand, dm-switch needs to process bulk data using messages so excessive use of GFP_NOIO could cause trouble. The patch also lowers the default number of arguments from 64 to 8, so that there is smaller load on GFP_NOIO allocations. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Acked-by: NAlasdair G Kergon <agk@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com>
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- 06 9月, 2013 2 次提交
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由 Mike Snitzer 提交于
Hold the mapped device's type_lock before calling populate_table() since it is where the table's type is determined based on the specified targets. There is no need to allow concurrent table loads to race to establish the table's targets or type. This eliminates the need to grab the lock in dm_table_set_type(). Also verify that the type_lock is held in both dm_set_md_type() and dm_get_md_type(). Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
It may be useful to switch a request-based table to the "error" target. Enhance the DM core to allow a hybrid target_type which is capable of handling either bios (via .map) or requests (via .map_rq). Add a request-based map function (.map_rq) to the "error" target_type; making it DM's first hybrid target. Train dm_table_set_type() to prefer the mapped device's established type (request-based or bio-based). If the mapped device doesn't have an established type default to making the table with the hybrid target(s) bio-based. Tested 'dmsetup wipe_table' to work on both bio-based and request-based devices. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NJoe Jin <joe.jin@oracle.com> Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com> Acked-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 11 7月, 2013 1 次提交
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由 Mikulas Patocka 提交于
This patch removes "io_lock" and "map_lock" in struct mapped_device and "holders" in struct dm_table and replaces these mechanisms with sleepable-rcu. Previously, the code would call "dm_get_live_table" and "dm_table_put" to get and release table. Now, the code is changed to call "dm_get_live_table" and "dm_put_live_table". dm_get_live_table locks sleepable-rcu and dm_put_live_table unlocks it. dm_get_live_table_fast/dm_put_live_table_fast can be used instead of dm_get_live_table/dm_put_live_table. These *_fast functions use non-sleepable RCU, so the caller must not block between them. If the code changes active or inactive dm table, it must call dm_sync_table before destroying the old table. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 10 5月, 2013 1 次提交
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由 Mike Snitzer 提交于
If device_not_write_same_capable() returns true then the iterate_devices loop in dm_table_supports_write_same() should return false. Reported-by: NBharata B Rao <bharata.rao@gmail.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # v3.8+ Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 02 3月, 2013 2 次提交
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由 Alasdair G Kergon 提交于
Use 'bio' in the name of variables and functions that deal with bios rather than 'request' to avoid confusion with the normal block layer use of 'request'. No functional changes. Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Wang Sheng-Hui 提交于
If allocation fails, the local var *t is not used any more after kfree. Don't need to reset it to NULL. Remove the unnecesary NULL set here. Signed-off-by: NWang Sheng-Hui <shhuiw@gmail.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 22 12月, 2012 3 次提交
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由 Mikulas Patocka 提交于
Introduce a field per_bio_data_size in struct dm_target. Targets can set this field in the constructor. If a target sets this field to a non-zero value, "per_bio_data_size" bytes of auxiliary data are allocated for each bio submitted to the target. These data can be used for any purpose by the target and help us improve performance by removing some per-target mempools. Per-bio data is accessed with dm_per_bio_data. The argument data_size must be the same as the value per_bio_data_size in dm_target. If the target has a pointer to per_bio_data, it can get a pointer to the bio with dm_bio_from_per_bio_data() function (data_size must be the same as the value passed to dm_per_bio_data). Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
Allow targets to opt in to WRITE SAME support by setting 'num_write_same_requests' in the dm_target structure. A dm device will only advertise WRITE SAME support if all its targets and all its underlying devices support it. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
WRITE SAME bios are not yet handled correctly by device-mapper so disable their use on device-mapper devices by setting max_write_same_sectors to zero. As an example, a ciphertext device is incompatible because the data gets changed according to the location at which it written and so the dm crypt target cannot support it. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org Cc: Milan Broz <mbroz@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 27 9月, 2012 2 次提交
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由 Mike Snitzer 提交于
Add a safety net that will re-use the DM device's existing limits in the event that DM device has a temporary table that doesn't have any component devices. This is to reduce the chance that requests not respecting the hardware limits will reach the device. DM recalculates queue limits based only on devices which currently exist in the table. This creates a problem in the event all devices are temporarily removed such as all paths being lost in multipath. DM will reset the limits to the maximum permissible, which can then assemble requests which exceed the limits of the paths when the paths are restored. The request will fail the blk_rq_check_limits() test when sent to a path with lower limits, and will be retried without end by multipath. This became a much bigger issue after v3.6 commit fe86cdce ("block: do not artificially constrain max_sectors for stacking drivers"). Reported-by: NDavid Jeffery <djeffery@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Milan Broz 提交于
Always clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not have it set. Otherwise devices with predictable characteristics may contribute entropy. QUEUE_FLAG_ADD_RANDOM specifies whether or not queue IO timings contribute to the random pool. For bio-based targets this flag is always 0 because such devices have no real queue. For request-based devices this flag was always set to 1 by default. Now set it according to the flags on underlying devices. If there is at least one device which should not contribute, set the flag to zero: If a device, such as fast SSD storage, is not suitable for supplying entropy, a request-based queue stacked over it will not be either. Because the checking logic is exactly same as for the rotational flag, share the iteration function with device_is_nonrot(). Signed-off-by: NMilan Broz <mbroz@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 27 7月, 2012 1 次提交
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由 Joe Thornber 提交于
Allow targets to override the 'supports flush' calculation. Set 'flush_supported' if a target needs to receive flushes regardless of whether or not its underlying devices have support. Signed-off-by: NJoe Thornber <ejt@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 29 3月, 2012 2 次提交
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由 Mikulas Patocka 提交于
Device mapper uses sscanf to convert arguments to numbers. The problem is that the way we use it ignores additional unmatched characters in the scanned string. For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number, but also it will match number with some garbage appended, like "123abc". As a result, device mapper accepts garbage after some numbers. For example the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"' will pass without an error. This patch fixes all sscanf uses in device mapper. It appends "%c" with a pointer to a dummy character variable to every sscanf statement. The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds only if string is a null-terminated number (optionally preceded by some whitespace characters). If there is some character appended after the number, sscanf matches "%c", writes the character to the dummy variable and returns 2. We check the return value for 1 and consequently reject numbers with some garbage appended. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Acked-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Hannes Reinecke 提交于
free_devices in dm_table.c already uses list_for_each(), so we don't need to check if the list is empty. Signed-off-by: NHannes Reinecke <hare@suse.de> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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- 11 1月, 2012 1 次提交
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由 Martin K. Petersen 提交于
Stacking driver queue limits are typically bounded exclusively by the capabilities of the low level devices, not by the stacking driver itself. This patch introduces blk_set_stacking_limits() which has more liberal metrics than the default queue limits function. This allows us to inherit topology parameters from bottom devices without manually tweaking the default limits in each driver prior to calling the stacking function. Since there is now a clear distinction between stacking and low-level devices, blk_set_default_limits() has been modified to carry the more conservative values that we used to manually set in blk_queue_make_request(). Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com> Acked-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NJens Axboe <axboe@kernel.dk>
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- 01 11月, 2011 4 次提交
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由 Alasdair G Kergon 提交于
Introduce DM_TARGET_IMMUTABLE to indicate that the target type cannot be mixed with any other target type, and once loaded into a device, it cannot be replaced with a table containing a different type. The thin provisioning pool device will use this. Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Alasdair G Kergon 提交于
Add a target feature flag DM_TARGET_ALWAYS_WRITEABLE to indicate that a target does not support read-only mode. The initial implementation of the thin provisioning target uses this. Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Alasdair G Kergon 提交于
Introduce the concept of a singleton table which contains exactly one target. If a target type sets the DM_TARGET_SINGLETON feature bit device-mapper will ensure that any table that includes that target contains no others. The thin provisioning pool target uses this. Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mandeep Singh Baines 提交于
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: NJ. Richard Barnette <jrbarnette@chromium.org> Signed-off-by: NMandeep Singh Baines <msb@chromium.org> Signed-off-by: NMike 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: NAlasdair G Kergon <agk@redhat.com>
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- 26 9月, 2011 2 次提交
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由 Milan Broz 提交于
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: NMilan Broz <mbroz@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
Commit a63a5cf8 (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: NZdenek Kabelac <zkabelac@redhat.com> Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com> Cc: stable@kernel.org # 2.6.39
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- 02 8月, 2011 5 次提交
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由 Mike Snitzer 提交于
DM has always advertised both REQ_FLUSH and REQ_FUA flush capabilities regardless of whether or not a given DM device's underlying devices also advertised a need for them. Block's flush-merge changes from 2.6.39 have proven to be more costly for DM devices. Performance regressions have been reported even when DM's underlying devices do not advertise that they have a write cache. Fix the performance regressions by configuring a DM device's flushing capabilities based on those of the underlying devices' capabilities. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
Move multipath target argument parsing code into dm-table so other targets can share it. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mikulas Patocka 提交于
Add a new flag DMF_MERGE_IS_OPTIONAL to struct mapped_device to indicate whether the device can accept bios larger than the size its merge function returns. When set, use this to send large bios to snapshots which can split them if necessary. Snapshot I/O may be significantly fragmented and this approach seems to improve peformance. Before the patch, dm_set_device_limits restricted bio size to page size if the underlying device had a merge function and the target didn't provide a merge function. After the patch, dm_set_device_limits restricts bio size to page size if the underlying device has a merge function, doesn't have DMF_MERGE_IS_OPTIONAL flag and the target doesn't provide a merge function. The snapshot target can't provide a merge function because when the merge function is called, it is impossible to determine where the bio will be remapped. Previously this led us to impose a 4k limit, which we can now remove if the snapshot store is located on a device without a merge function. Together with another patch for optimizing full chunk writes, it improves performance from 29MB/s to 40MB/s when writing to the filesystem on snapshot store. If the snapshot store is placed on a non-dm device with a merge function (such as md-raid), device mapper still limits all bios to page size. Signed-off-by: NMikulas Patocka <mpatocka@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Mike Snitzer 提交于
There is no need for __table_get_device to be factored out. Also move the exports to the end of their respective functions. Signed-off-by: NMike Snitzer <snitzer@redhat.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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由 Joe Perches 提交于
Use vzalloc() instead of vmalloc()+memset(). Signed-off-by: NJoe Perches <joe@perches.com> Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
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