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path: root/drivers/md
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2007-11-14raid5: fix unending write sequenceDan Williams
<debug output from Joel's system> handling stripe 7629696, state=0x14 cnt=1, pd_idx=2 ops=0:0:0 check 5: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ffcffcc0 written 0000000000000000 check 4: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fdd4e360 written 0000000000000000 check 3: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000 check 2: state 0x1 toread 0000000000000000 read 0000000000000000 write 0000000000000000 written 0000000000000000 check 1: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800ff517e40 written 0000000000000000 check 0: state 0x6 toread 0000000000000000 read 0000000000000000 write fffff800fd4cae60 written 0000000000000000 locked=4 uptodate=2 to_read=0 to_write=4 failed=0 failed_num=0 for sector 7629696, rmw=0 rcw=0 </debug> These blocks were prepared to be written out, but were never handled in ops_run_biodrain(), so they remain locked forever. The operations flags are all clear which means handle_stripe() thinks nothing else needs to be done. This state suggests that the STRIPE_OP_PREXOR bit was sampled 'set' when it should not have been. This patch cleans up cases where the code looks at sh->ops.pending when it should be looking at the consistent stack-based snapshot of the operations flags. Report from Joel: Resync done. Patch fix this bug. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Joel Bertrand <joel.bertrand@systella.fr> Cc: <stable@kernel.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-09Add UNPLUG traces to all appropriate placesAlan D. Brunelle
Added blk_unplug interface, allowing all invocations of unplugs to result in a generated blktrace UNPLUG. Signed-off-by: Alan D. Brunelle <Alan.Brunelle@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-11-05md: fix misapplied patch in raid5.cNeil Brown
commit 4ae3f847e49e3787eca91bced31f8fd328d50496 ("md: raid5: fix clearing of biofill operations") did not get applied correctly, presumably due to substantial similarities between handle_stripe5 and handle_stripe6. This patch moves the chunk of new code from handle_stripe6 (where it isn't needed (yet)) to handle_stripe5. Signed-off-by: Neil Brown <neilb@suse.de> Cc: "Dan Williams" <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-02dm: bounce_pfn limit addedVasily Averin
Device mapper uses its own bounce_pfn that may differ from one on underlying device. In that way dm can build incorrect requests that contain sg elements greater than underlying device is able to handle. This is the cause of slab corruption in i2o layer, occurred on i386 arch when very long direct IO requests are addressed to dm-over-i2o device. Signed-off-by: Vasily Averin <vvs@sw.ru> Cc: <stable@kernel.org> Cc: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-29x86 merge fallout: umlAl Viro
Don't undef __i386__/__x86_64__ in uml anymore, make sure that (few) places that required adjusting the ifdefs got those. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-27[CRYPTO] users: Fix up scatterlist conversion errorsHerbert Xu
This patch fixes the errors made in the users of the crypto layer during the sg_init_table conversion. It also adds a few conversions that were missing altogether. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-24SG: Change sg_set_page() to take length and offset argumentJens Axboe
Most drivers need to set length and offset as well, so may as well fold those three lines into one. Add sg_assign_page() for those two locations that only needed to set the page, where the offset/length is set outside of the function context. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-23md: raid5: fix clearing of biofill operationsDan Williams
ops_complete_biofill() runs outside of spin_lock(&sh->lock) and clears the 'pending' and 'ack' bits. Since the test_and_ack_op() macro only checks against 'complete' it can get an inconsistent snapshot of pending work. Move the clearing of these bits to handle_stripe5(), under the lock. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Joel Bertrand <joel.bertrand@systella.fr> Signed-off-by: Neil Brown <neilb@suse.de> Cc: Stable <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-23md: fix an unsigned compare to allow creation of bitmaps with v1.0 metadataNeilBrown
As page->index is unsigned, this all becomes an unsigned comparison, which almost always returns an error. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Stable <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-22[SG] Update drivers to use sg helpersJens Axboe
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (74 commits) fix do_sys_open() prototype sysfs: trivial: fix sysfs_create_file kerneldoc spelling mistake Documentation: Fix typo in SubmitChecklist. Typo: depricated -> deprecated Add missing profile=kvm option to Documentation/kernel-parameters.txt fix typo about TBI in e1000 comment proc.txt: Add /proc/stat field small documentation fixes Fix compiler warning in smount example program from sharedsubtree.txt docs/sysfs: add missing word to sysfs attribute explanation documentation/ext3: grammar fixes Documentation/java.txt: typo and grammar fixes Documentation/filesystems/vfs.txt: typo fix include/asm-*/system.h: remove unused set_rmb(), set_wmb() macros trivial copy_data_pages() tidy up Fix typo in arch/x86/kernel/tsc_32.c file link fix for Pegasus USB net driver help remove unused return within void return function Typo fixes retrun -> return x86 hpet.h: remove broken links ...
2007-10-20dm crypt: tidy pendingMilan Broz
Add crypt prefix to dec_pending to avoid confusing it in backtraces with the dm core function of the same name. No functional change here. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm mpath: send ueventsMike Anderson
This patch adds calls to dm_path_event for a failed path and a reinstated path. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: uevent generate eventsMike Anderson
This patch adds support for the dm_path_event dm_send_event functions which create and send udev events. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: add uevent to coreMike Anderson
This patch adds a uevent skeleton to device-mapper. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: export name and uuidMike Anderson
This patch adds a function to obtain a copy of a mapped device's name and uuid. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm raid1: add mirror_set to struct mirrorJonathan Brassow
Store a pointer to the owning mirror_set structure within each mirror structure for a subsequent patch to use. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm log: split suspendJonathan Brassow
There are now two phases to a suspend in device-mapper - presuspend and postsuspend. This patch removes the single 'suspend' in the logging API and replaces it with 'presuspend' and 'postsuspend' functions to align it better with core device-mapper. A subsequent patch will make use of 'presuspend'. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm mpath: hp retry if not readyDave Wysochanski
This patch adds retries to the hp hardware handler, and utilizes the MP_RETRY flag of dm-multipath. For now in the hp handler, if we get a pg_init completed with a check condition we just assume we can retry the pg_init command. We make this assumption because of incomplete data on specific check condition code of the HP hardware, and because testing has shown the HP path initialization command to be idempotent. The number of times we retry is settable via the "pg_init_retries" multipath map feature. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm mpath: add hp handlerDave Wysochanski
This patch adds the most basic dm-multipath hardware support for the HP active/passive arrays. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm mpath: add retry pg initDave Wysochanski
This patch allows a failed path group initialisation command to be retried. It adds a generic MP_RETRY flag and a "pg_init_retries" feature to device-mapper multipath which limits the number of retries. 1. A hw handler sends a path initialization command to the storage and the command completes with an error code indicating the command should be retried. 2. The hardware handler calls dm_pg_init_complete() with MP_RETRY set in err_flags to ask the dm multipath core to retry. 3. If the retry limit has not been exceeded, pg_init() is retried. Otherwise fail_path() is called. If you are using the userspace multipath-tools or device-mapper-multipath package, you can set pg_init_retries in the 'device' section of your /etc/multipath.conf file. For example: features "2 pg_init_retries 7" The number of PG retries attempted is reported in the 'dmsetup status' output. Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Acked-by: Mike Christie <michaelc@cs.wisc.edu> Acked-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: tidy labelsMilan Broz
Replace numbers with names in labels in error paths, to avoid confusion when new one get added between existing ones. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: tidy whitespaceMilan Broz
Clean up, convert some spaces to tabs. No functional change here. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: add post processing queueMilan Broz
Add post-processing queue (per crypt device) for read operations. Current implementation uses only one queue for all operations and this can lead to starvation caused by many requests waiting for memory allocation. But the needed memory-releasing operation is queued after these requests (in the same queue). Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: use per device singlethread workqueuesMilan Broz
Use a separate single-threaded workqueue for each crypt device instead of one global workqueue. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm mpath: emc fix an error messageAlasdair G Kergon
Correct an error message, reported by Michael Wood <michael@frogfoot.com>. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: bio_list macro renamingAlasdair G Kergon
Remove BIO_LIST and DEFINE_BIO_LIST macros that gain us nothing since contents are initialised to NULL. Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm io:ctl remove vmalloc void castJesper Juhl
In drivers/md/dm-ioctl.c::copy_params() there's a call to vmalloc() where we currently cast the return value, but that's pretty pointless given that vmalloc() returns "void *". Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: tidy bio_io_error usageMilan Broz
Use bio_io_error() in only two places and tidy the code, preparing for later patches. There is no functional change in this patch. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20kcopyd use mutex instead of semaphoreMatthias Kaehlcke
Kcopyd uses a semaphore as mutex. Use the mutex API instead of the (binary) semaphore, Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-10-20dm: use kzallocDmitry Monakhov
Convert kmalloc() + memset() to kzalloc(). Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: use is_power_of_2vignesh babu
Replacing n & (n - 1) for power of 2 check by is_power_of_2(n) Signed-off-by: vignesh babu <vignesh.babu@wipro.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: fix thaw_bdevJun'ichi Nomura
This patch fixes a bd_mount_sem counter corruption bug in device-mapper. thaw_bdev() should be called only when freeze_bdev() was called for the device. Otherwise, thaw_bdev() will up bd_mount_sem and corrupt the semaphore counter. struct block_device with the corrupted semaphore may remain in slab cache and be reused later. Attached patch will fix it by calling unlock_fs() instead. unlock_fs() will determine whether it should call thaw_bdev() by checking the device is frozen or not. Easy reproducer is: #!/bin/sh while [ 1 ]; do dmsetup --notable create a dmsetup --nolockfs suspend a dmsetup remove a done It's not easy to see the effect of corrupted semaphore. So I have tested with putting printk below in bdev_alloc_inode(): if (atomic_read(&ei->bdev.bd_mount_sem.count) != 1) printk(KERN_DEBUG "Incorrect semaphore count = %d (%p)\n", atomic_read(&ei->bdev.bd_mount_sem.count), &ei->bdev); Without the patch, I saw something like: Incorrect semaphore count = 17 (f2ab91c0) With the patch, the message didn't appear. The bug was introduced in 2.6.16 with this bug fix: commit d9dde59ba03095e526640988c0fedd75e93bc8b7 Date: Fri Feb 24 13:04:24 2006 -0800 [PATCH] dm: missing bdput/thaw_bdev at removal Need to unfreeze and release bdev otherwise the bdev inode with inconsistent state is reused later and cause problem. and backported to 2.6.15.5. It occurs only in free_dev(), which is called only when the dm device is removed. The buggy code is executed only if md->suspended_bdev is non-NULL and that can happen only when the device was suspended without noflush. Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: stable@kernel.org
2007-10-20dm delay: fix statusMilan Broz
Fix missing space in dm-delay target status output if separate read and write delay are configured. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm delay: fix ctr error pathsDmitry Monakhov
Add missing 'dm_put_device' to dm-delay target constructor. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm raid1: fix leakageDmitry Monakhov
Add missing 'dm_io_client_destroy' to alloc_context error path. Reorganize mirror constructor error path in order to prevent workqueue leakage. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: missing kfree in ctr error pathDmitry Monakhov
Insert missing kfree() in crypt_iv_essiv_ctr() error path. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm crypt: drop device ref in ctr error pathDmitry Monakhov
Add a missing 'dm_put_device' in an error path in crypt target constructor. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm io:ctl use constant struct sizeMilan Broz
Make size of dm_ioctl struct always 312 bytes on all supported architectures. This change retains compatibility with already-compiled code because it uses an embedded offset to locate the payload that follows the structure. On 64-bit architectures there is no change at all; on 32-bit we are increasing the size of dm-ioctl from 308 to 312 bytes. Currently with 32-bit userspace / 64-bit kernel on x86_64 some ioctls (including rename, message) are incorrectly rejected by the comparison against 'param + 1'. This breaks userspace lvrename and multipath 'fail_if_no_path' changes, for example. (BTW Device-mapper uses its own versioning and ignores the ioctl size bits. Only the generic ioctl compat code on mixed arches checks them, and that will continue to accept both sizes for now, but we intend to list 308 as deprecated and eventually remove it.) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: Guido Guenther <agx@sigxcpu.org> Cc: Kevin Corry <kevcorry@us.ibm.com> Cc: stable@kernel.org
2007-10-20dm mpath: rdac fix init raceBryn M. Reeves
Re-order the initialisation of dm-rdac to avoid registering the hw handler before the workqueue has been initialised. Closes a race that would potentially give an oops. Signed-off-by: Bryn M. Reeves <breeves@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-19Convert files to UTF-8 and some cleanupsJan Engelhardt
* Convert files to UTF-8. * Also correct some people's names (one example is Eißfeldt, which was found in a source file. Given that the author used an ß at all in a source file indicates that the real name has in fact a 'ß' and not an 'ss', which is commonly used as a substitute for 'ß' when limited to 7bit.) * Correct town names (Goettingen -> Göttingen) * Update Eberhard Mönkeberg's address (http://lkml.org/lkml/2007/1/8/313) Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-19Fix misspellings of "system", "controller", "interrupt" and "necessary".Robert P. J. Day
Fix the various misspellings of "system", controller", "interrupt" and "[un]necessary". Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-19Use helpers to obtain task pid in printksPavel Emelyanov
The task_struct->pid member is going to be deprecated, so start using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in the kernel. The first thing to start with is the pid, printed to dmesg - in this case we may safely use task_pid_nr(). Besides, printks produce more (much more) than a half of all the explicit pid usage. [akpm@linux-foundation.org: git-drm went and changed lots of stuff] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17md: make sure read errors are auto-corrected during a 'check' resync in raid1NeilBrown
Whenever a read error is found, we should attempt to overwrite with correct data to 'fix' it. However when do a 'check' pass (which compares data blocks that are successfully read, but doesn't normally overwrite) we don't do that. We should. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17md: expose the degraded status of an assembled array through sysfsIustin Pop
The 'degraded' attribute is useful to quickly determine if the array is degraded, instead of parsing 'mdadm -D' output or relying on the other techniques (number of working devices against number of defined devices, etc.). The md code already keeps track of this attribute, so it's useful to export it. Signed-off-by: Iustin Pop <iusty@k1024.org> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17md: 'sync_action' in sysfs returns wrong value for readonly arraysNeilBrown
When an array is started read-only, MD_RECOVERY_NEEDED can be set but no recovery will be running. This causes 'sync_action' to report the wrong value. We could remove the test for MD_RECOVERY_NEEDED, but doing so would leave a small gap after requesting a sync action, where 'sync_action' would still report the old value. So make sure that for a read-only array, 'sync_action' always returns 'idle'. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17md: fix a bug in some never-used code.NeilBrown
http://bugzilla.kernel.org/show_bug.cgi?id=3277 There is a seq_printf here that isn't being passed a 'seq'. Howeve as the code is inside #ifdef MD_DEBUG, nobody noticed. Also remove some extra spaces. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17md: software Raid autodetect dev list not arrayMichael J. Evans
In current release kernels the md module (Software RAID) uses a static array (dev_t[128]) to store partition/device info temporarily for autostart. I discovered this (and that the devices are added as disks/partitions are discovered at boot) while I was debugging why only one of my MD arrays would come up whole, while all the others were short a disk. I eventually discovered that it was enumerating through all of 9 of my 11 hds (2 had only 4 partitions apiece) while the other 9 have 15 partitions (I wanted 64 per drive...). The last partition of the 8th drive in my 9 drive raid 5 sets wasn't added, thus making the final md array short both a parity and data disk, and it was started later, elsewhere. This patch replaces that static array with a list. [akpm@linux-foundation.org: removed unused var] Signed-off-by: Michael J. Evans <mjevans1983@gmail.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16Fix memory leak in dm-cryptNeil Brown
dm-crypt used the ->bi_size member in the bio endio handling to free the appropriate pages, but it frees all of it from both call paths. With the ->bi_end_io() changes, ->bi_size was always 0 since we don't do partial completes. This caused dm-crypt to leak memory. Fix this by removing the size argument from crypt_free_buffer_pages(). Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16block: convert blkdev_issue_flush() to use empty barriersJens Axboe
Then we can get rid of ->issue_flush_fn() and all the driver private implementations of that. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>