linux_dsm_epyc7002/include
Martin K. Petersen d93ba7a5a9 block: Add discard flag to blkdev_issue_zeroout() function
blkdev_issue_discard() will zero a given block range. This is done by
way of explicit writing, thus provisioning or allocating the blocks on
disk.

There are use cases where the desired behavior is to zero the blocks but
unprovision them if possible. The blocks must deterministically contain
zeroes when they are subsequently read back.

This patch adds a flag to blkdev_issue_zeroout() that provides this
variant. If the discard flag is set and a block device guarantees
discard_zeroes_data we will use REQ_DISCARD to clear the block range. If
the device does not support discard_zeroes_data or if the discard
request fails we will fall back to first REQ_WRITE_SAME and then a
regular REQ_WRITE.

Also update the callers of blkdev_issue_zero() to reflect the new flag
and make sb_issue_zeroout() prefer the discard approach.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-21 10:41:46 -07:00
..
acpi Merge branches 'acpi-scan', 'acpi-utils' and 'acpi-pm' 2014-12-18 18:42:56 +01:00
asm-generic ARM: SoC/iommu configuration for 3.19 2014-12-16 14:53:01 -08:00
clocksource
crypto
drm Revert "drm/gem: Warn on illegal use of the dumb buffer interface v2" 2014-12-24 13:13:22 +10:00
dt-bindings Please consider pulling the clk framework changes toward 3.19. It is 2014-12-20 16:42:36 -08:00
keys
kvm arm/arm64: KVM: Require in-kernel vgic for the arch timers 2014-12-15 11:50:42 +01:00
linux block: Add discard flag to blkdev_issue_zeroout() function 2015-01-21 10:41:46 -07:00
math-emu
media
memory
misc
net Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-12-16 15:53:03 -08:00
pcmcia
ras
rdma IB/core: Implement support for MMU notifiers regarding on demand paging regions 2014-12-15 18:13:36 -08:00
rxrpc
scsi SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
soc Merge branch 'at91/cleanup5' into next/drivers 2014-12-08 18:29:20 +01:00
sound sound updates for 3.19-rc1 2014-12-11 13:20:50 -08:00
target SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
trace SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
uapi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-12-19 18:02:22 -08:00
video
xen
Kbuild