Mike Snitzer 586b286b11 dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE ... Setting the dm-crypt device's max_segment_size to PAGE_SIZE is an unfortunate constraint that is required to avoid the potential for exceeding dm-crypt's underlying device's max_segments limits -- due to crypt_alloc_buffer() possibly allocating pages for the encryption bio that are not as physically contiguous as the original bio. It is interesting to note that this problem was already fixed back in 2007 via commit 91e106259 ("dm crypt: use bio_add_page"). But Linux 4.0 commit cf2f1abfb ("dm crypt: don't allocate pages for a partial request") regressed dm-crypt back to _not_ using bio_add_page(). But given dm-crypt's cpu parallelization changes all depend on commit cf2f1abfb's abandoning of the more complex io fragments processing that dm-crypt previously had we cannot easily go back to using bio_add_page(). So all said the cleanest way to resolve this issue is to fix dm-crypt to properly constrain the original bios entering dm-crypt so the encryption bios that dm-crypt generates from the original bios are always compatible with the underlying device's max_segments queue limits. It should be noted that technically Linux 4.3 does _not_ need this fix because of the block core's new late bio-splitting capability. But, it is reasoned, there is little to be gained by having the block core split the encrypted bio that is composed of PAGE_SIZE segments. That said, in the future we may revert this change. Fixes: cf2f1abfb ("dm crypt: don't allocate pages for a partial request") Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=104421 Suggested-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org # 4.0+		2015-09-14 12:04:24 -04:00
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bcache
persistent-data
bitmap.c
bitmap.h
dm-bio-prison.c
dm-bio-prison.h
dm-bio-record.h
dm-bufio.c
dm-bufio.h
dm-builtin.c
dm-cache-block-types.h
dm-cache-metadata.c
dm-cache-metadata.h
dm-cache-policy-cleaner.c
dm-cache-policy-internal.h
dm-cache-policy-mq.c
dm-cache-policy-smq.c
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-crypt.c	dm crypt: constrain crypt device's max_segment_size to PAGE_SIZE	2015-09-14 12:04:24 -04:00
dm-delay.c
dm-era-target.c
dm-exception-store.c
dm-exception-store.h
dm-flakey.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-io.c
dm-ioctl.c
dm-kcopyd.c
dm-linear.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-log-userspace-base.c
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-log.c
dm-mpath.c
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid.c
dm-raid1.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-region-hash.c
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c
dm-snap-transient.c
dm-snap.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-stats.c
dm-stats.h
dm-stripe.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-switch.c
dm-sysfs.c
dm-table.c
dm-target.c
dm-thin-metadata.c
dm-thin-metadata.h
dm-thin.c	dm thin: disable discard support for thin devices if pool's is disabled	2015-09-13 21:32:10 -04:00
dm-uevent.c
dm-uevent.h
dm-verity.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm-zero.c
dm.c	Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm	2015-09-02 16:35:26 -07:00
dm.h
faulty.c
Kconfig	SCSI misc on 20150911	2015-09-11 18:15:18 -07:00
linear.c
linear.h
Makefile
md-cluster.c	md-cluster: remove inappropriate try_module_get from join()	2015-08-31 19:43:17 +02:00
md-cluster.h
md.c	Merge linux-block/for-4.3/core into md/for-linux	2015-09-05 11:08:32 +02:00
md.h
multipath.c
multipath.h
raid0.c	Merge linux-block/for-4.3/core into md/for-linux	2015-09-05 11:08:32 +02:00
raid0.h
raid1.c	Merge linux-block/for-4.3/core into md/for-linux	2015-09-05 11:08:32 +02:00
raid1.h	md/raid1: ensure device failure recorded before write request returns.	2015-08-31 19:43:23 +02:00
raid5.c	Merge linux-block/for-4.3/core into md/for-linux	2015-09-05 11:08:32 +02:00
raid5.h	md/raid5: ensure device failure recorded before write request returns.	2015-08-31 19:43:59 +02:00
raid10.c	Merge linux-block/for-4.3/core into md/for-linux	2015-09-05 11:08:32 +02:00
raid10.h	md/raid10: ensure device failure recorded before write request returns.	2015-08-31 19:43:45 +02:00