Add basic support for polling for specific IO to complete. This uses
the cookie that blk-mq passes back, which enables the block layer
to pass this cookie to the driver to spin for a specific request.
This will be combined with request latency tracking, so we can make
qualified decisions about when to poll and when not to. For now, for
benchmark purposes, we add a sysfs file that controls whether polling
is enabled or not.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Pull block reservation support from Jens Axboe:
"This adds support for persistent reservations, both at the core level,
as well as for sd and NVMe"
[ Background from the docs: "Persistent Reservations allow restricting
access to block devices to specific initiators in a shared storage
setup. All implementations are expected to ensure the reservations
survive a power loss and cover all connections in a multi path
environment" ]
* 'for-4.4/reservations' of git://git.kernel.dk/linux-block:
NVMe: Precedence error in nvme_pr_clear()
nvme: add missing endianess annotations in nvme_pr_command
NVMe: Add persistent reservation ops
sd: implement the Persistent Reservation API
block: add an API for Persistent Reservations
block: cleanup blkdev_ioctl
This commits adds a driver API and ioctls for controlling Persistent
Reservations s/genericly/generically/ at the block layer. Persistent
Reservations are supported by SCSI and NVMe and allow controlling who gets
access to a device in a shared storage setup.
Note that we add a pr_ops structure to struct block_device_operations
instead of adding the members directly to avoid bloating all instances
of devices that will never support Persistent Reservations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
A trace like the following proceeds a crash in bio_integrity_process()
when it goes to use an already freed blk_integrity profile.
BUG: unable to handle kernel paging request at ffff8800d31b10d8
IP: [<ffff8800d31b10d8>] 0xffff8800d31b10d8
PGD 2f65067 PUD 21fffd067 PMD 80000000d30001e3
Oops: 0011 [#1] SMP
Dumping ftrace buffer:
---------------------------------
ndctl-2222 2.... 44526245us : disk_release: pmem1s
systemd--2223 4.... 44573945us : bio_integrity_endio: pmem1s
<...>-409 4.... 44574005us : bio_integrity_process: pmem1s
---------------------------------
[..]
Call Trace:
[<ffffffff8144e0f9>] ? bio_integrity_process+0x159/0x2d0
[<ffffffff8144e4f6>] bio_integrity_verify_fn+0x36/0x60
[<ffffffff810bd2dc>] process_one_work+0x1cc/0x4e0
Given that a request_queue is pinned while i/o is in flight and that a
gendisk is allowed to have a shorter lifetime, move blk_integrity to
request_queue to satisfy requests arriving after the gendisk has been
torn down.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
[martin: fix the CONFIG_BLK_DEV_INTEGRITY=n case]
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Allow pmem, and other synchronous/bio-based block drivers, to fallback
on a per-cpu reference count managed by the core for tracking queue
live/dead state.
The existing per-cpu reference count for the blk_mq case is promoted to
be used in all block i/o scenarios. This involves initializing it by
default, waiting for it to drop to zero at exit, and holding a live
reference over the invocation of q->make_request_fn() in
generic_make_request(). The blk_mq code continues to take its own
reference per blk_mq request and retains the ability to freeze the
queue, but the check that the queue is frozen is moved to
generic_make_request().
This fixes crash signatures like the following:
BUG: unable to handle kernel paging request at ffff880140000000
[..]
Call Trace:
[<ffffffff8145e8bf>] ? copy_user_handle_tail+0x5f/0x70
[<ffffffffa004e1e0>] pmem_do_bvec.isra.11+0x70/0xf0 [nd_pmem]
[<ffffffffa004e331>] pmem_make_request+0xd1/0x200 [nd_pmem]
[<ffffffff811c3162>] ? mempool_alloc+0x72/0x1a0
[<ffffffff8141f8b6>] generic_make_request+0xd6/0x110
[<ffffffff8141f966>] submit_bio+0x76/0x170
[<ffffffff81286dff>] submit_bh_wbc+0x12f/0x160
[<ffffffff81286e62>] submit_bh+0x12/0x20
[<ffffffff813395bd>] jbd2_write_superblock+0x8d/0x170
[<ffffffff8133974d>] jbd2_mark_journal_empty+0x5d/0x90
[<ffffffff813399cb>] jbd2_journal_destroy+0x24b/0x270
[<ffffffff810bc4ca>] ? put_pwq_unlocked+0x2a/0x30
[<ffffffff810bc6f5>] ? destroy_workqueue+0x225/0x250
[<ffffffff81303494>] ext4_put_super+0x64/0x360
[<ffffffff8124ab1a>] generic_shutdown_super+0x6a/0xf0
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Up until now the_integrity profile has been dynamically allocated and
attached to struct gendisk after the disk has been made active.
This causes problems because NVMe devices need to register the profile
prior to the partition table being read due to a mandatory metadata
buffer requirement. In addition, DM goes through hoops to deal with
preallocating, but not initializing integrity profiles.
Since the integrity profile is small (4 bytes + a pointer), Christoph
suggested moving it to struct gendisk proper. This requires several
changes:
- Moving the blk_integrity definition to genhd.h.
- Inlining blk_integrity in struct gendisk.
- Removing the dynamic allocation code.
- Adding helper functions which allow gendisk to set up and tear down
the integrity sysfs dir when a disk is added/deleted.
- Adding a blk_integrity_revalidate() callback for updating the stable
pages bdi setting.
- The calls that depend on whether a device has an integrity profile or
not now key off of the bi->profile pointer.
- Simplifying the integrity support routines in DM (Mike Snitzer).
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The per-device properties in the blk_integrity structure were previously
unsigned short. However, most of the values fit inside a char. The only
exception is the data interval size and we can work around that by
storing it as a power of two.
This cuts the size of the dynamic portion of blk_integrity in half.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We previously made a complete copy of a device's data integrity profile
even though several of the fields inside the blk_integrity struct are
pointers to fixed template entries in t10-pi.c.
Split the static and per-device portions so that we can reference the
template directly.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The integrity kobject purely exists to support the integrity
subdirectory in sysfs and doesn't really have anything to do with the
blk_integrity data structure. Move the kobject to struct gendisk where
it belongs.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
There is a race between cpu hotplug handling and adding/deleting
gendisk for blk-mq, where both are trying to register and unregister
the same sysfs entries.
null_add_dev
--> blk_mq_init_queue
--> blk_mq_init_allocated_queue
--> add to 'all_q_list' (*)
--> add_disk
--> blk_register_queue
--> blk_mq_register_disk (++)
null_del_dev
--> del_gendisk
--> blk_unregister_queue
--> blk_mq_unregister_disk (--)
--> blk_cleanup_queue
--> blk_mq_free_queue
--> del from 'all_q_list' (*)
blk_mq_queue_reinit
--> blk_mq_sysfs_unregister (-)
--> blk_mq_sysfs_register (+)
While the request queue is added to 'all_q_list' (*),
blk_mq_queue_reinit() can be called for the queue anytime by CPU
hotplug callback. But blk_mq_sysfs_unregister (-) and
blk_mq_sysfs_register (+) in blk_mq_queue_reinit must not be called
before blk_mq_register_disk (++) and after blk_mq_unregister_disk (--)
is finished. Because '/sys/block/*/mq/' is not exists.
There has already been BLK_MQ_F_SYSFS_UP flag in hctx->flags which can
be used to track these sysfs stuff, but it is only fixing this issue
partially.
In order to fix it completely, we just need per-queue flag instead of
per-hctx flag with appropriate locking. So this introduces
q->mq_sysfs_init_done which is properly protected with all_q_mutex.
Also, we need to ensure that blk_mq_map_swqueue() is called with
all_q_mutex is held. Since hctx->nr_ctx is reset temporarily and
updated in blk_mq_map_swqueue(), so we should avoid
blk_mq_register_hctx() seeing the temporary hctx->nr_ctx value
in CPU hotplug handling or adding/deleting gendisk .
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull block updates from Jens Axboe:
"This is a bit bigger than it should be, but I could (did) not want to
send it off last week due to both wanting extra testing, and expecting
a fix for the bounce regression as well. In any case, this contains:
- Fix for the blk-merge.c compilation warning on gcc 5.x from me.
- A set of back/front SG gap merge fixes, from me and from Sagi.
This ensures that we honor SG gapping for integrity payloads as
well.
- Two small fixes for null_blk from Matias, fixing a leak and a
capacity propagation issue.
- A blkcg fix from Tejun, fixing a NULL dereference.
- A fast clone optimization from Ming, fixing a performance
regression since the arbitrarily sized bio's were introduced.
- Also from Ming, a regression fix for bouncing IOs"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: fix bounce_end_io
block: blk-merge: fast-clone bio when splitting rw bios
block: blkg_destroy_all() should clear q->root_blkg and ->root_rl.blkg
block: Copy a user iovec if it includes gaps
block: Refuse adding appending a gapped integrity page to a bio
block: Refuse request/bio merges with gaps in the integrity payload
block: Check for gaps on front and back merges
null_blk: fix wrong capacity when bs is not 512 bytes
null_blk: fix memory leak on cleanup
block: fix bogus compiler warnings in blk-merge.c
rq_data_dir() returns either READ or WRITE (0 == READ, 1 == WRITE), not
a boolean value.
Now, admittedly the "!= 0" doesn't really change the value (0 stays as
zero, 1 stays as one), but it's not only redundant, it confuses gcc, and
causes gcc to warn about the construct
switch (rq_data_dir(req)) {
case READ:
...
case WRITE:
...
that we have in a few drivers.
Now, the gcc warning is silly and stupid (it seems to warn not about the
switch value having a different type from the case statements, but about
_any_ boolean switch value), but in this case the code itself is silly
and stupid too, so let's just change it, and get rid of warnings like
this:
drivers/block/hd.c: In function ‘hd_request’:
drivers/block/hd.c:630:11: warning: switch condition has boolean value [-Wswitch-bool]
switch (rq_data_dir(req)) {
The odd '!= 0' came in when "cmd_flags" got turned into a "u64" in
commit 5953316dbf ("block: make rq->cmd_flags be 64-bit") and is
presumably because the old code (that just did a logical 'and' with 1)
would then end up making the type of rq_data_dir() be u64 too.
But if we want to retain the old regular integer type, let's just cast
the result to 'int' rather than use that rather odd '!= 0'.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a driver sets the block queue virtual boundary mask, it means that
it cannot handle gaps so we must not allow those in the integrity
payload as well.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Fixed up by me to have duplicate integrity merge functions, depending
on whether block integrity is enabled or not. Fixes a compilations
issue with CONFIG_BLK_DEV_INTEGRITY unset.
Signed-off-by: Jens Axboe <axboe@fb.com>
1/ Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map. This facility is used by the pmem driver to
enable pfn_to_page() operations on the page frames returned by DAX
('direct_access' in 'struct block_device_operations'). For now, the
'memmap' allocation for these "device" pages comes from "System
RAM". Support for allocating the memmap from device memory will
arrive in a later kernel.
2/ Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3. Completion of
the conversion is targeted for v4.4.
3/ Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
4/ Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
5/ Miscellaneous updates and fixes to libnvdimm including support
for issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes.
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Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This update has successfully completed a 0day-kbuild run and has
appeared in a linux-next release. The changes outside of the typical
drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
the introduction of ZONE_DEVICE + devm_memremap_pages().
Summary:
- Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map.
This facility is used by the pmem driver to enable pfn_to_page()
operations on the page frames returned by DAX ('direct_access' in
'struct block_device_operations').
For now, the 'memmap' allocation for these "device" pages comes
from "System RAM". Support for allocating the memmap from device
memory will arrive in a later kernel.
- Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3.
Completion of the conversion is targeted for v4.4.
- Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
- Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
- Miscellaneous updates and fixes to libnvdimm including support for
issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes"
* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
libnvdimm, pmem: direct map legacy pmem by default
libnvdimm, pmem: 'struct page' for pmem
libnvdimm, pfn: 'struct page' provider infrastructure
x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
add devm_memremap_pages
mm: ZONE_DEVICE for "device memory"
mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
dax: drop size parameter to ->direct_access()
nd_blk: change aperture mapping from WC to WB
nvdimm: change to use generic kvfree()
pmem, dax: have direct_access use __pmem annotation
dax: update I/O path to do proper PMEM flushing
pmem: add copy_from_iter_pmem() and clear_pmem()
pmem, x86: clean up conditional pmem includes
pmem: remove layer when calling arch_has_wmb_pmem()
pmem, x86: move x86 PMEM API to new pmem.h header
libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
pmem: switch to devm_ allocations
devres: add devm_memremap
libnvdimm, btt: write and validate parent_uuid
...
We are checking for gaps to previous bio_vec, which can
only detect back merges gaps. Moreover, at the point where
we check for a gap, we don't know if we will attempt a back
or a front merge. Thus, check for gap to prev in a back merge
attempt and check for a gap to next in a front merge attempt.
Signed-off-by: Jens Axboe <axboe@fb.com>
[sagig: Minor rename change]
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
None of the implementations currently use it. The common
bdev_direct_access() entry point handles all the size checks before
calling ->direct_access().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Update the annotation for the kaddr pointer returned by direct_access()
so that it is a __pmem pointer. This is consistent with the PMEM driver
and with how this direct_access() pointer is used in the DAX code.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The SG_GAPS queue flag caused checks for bio vector alignment against
PAGE_SIZE, but the device may have different constraints. This patch
adds a queue limits so a driver with such constraints can set to allow
requests that would have been unnecessarily split. The new gaps check
takes the request_queue as a parameter to simplify the logic around
invoking this function.
This new limit makes the queue flag redundant, so removing it and
all usage. Device-mappers will inherit the correct settings through
blk_stack_limits().
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
A value of 2560 (1280k) will accommodate a 10-data-disk stripe
write with chunk size 128k. In the testing I've done using
iozone, fio, and aio-stress across a number of different storage
devices, a value of 1280 does not show a big performance
difference from 512, but will hopefully help software RAID
setups using SATA disks, as reported by Christoph.
NOTE: drivers/block/aoe/aoeblk.c sets its own max_hw_sectors_kb to
BLK_DEF_MAX_SECTORS. So, this patch essentially changes aeoblk to
Use a larger maximum sector size, and I did not test this.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This reverts commit 34b48db66e.
That commit caused performance regressions for streaming I/O
workloads on a number of different storage devices, from
SATA disks to external RAID arrays. It also managed to
trip up some buggy firmware in at least one drive, causing
data corruption.
The next patch will bump the default max_sectors_kb value to
1280, which will accommodate a 10-data-disk stripe write
with chunk size 128k. In the testing I've done using iozone,
fio, and aio-stress, a value of 1280 does not show a big
performance difference from 512. This will hopefully still
help the software RAID setup that Christoph saw the original
performance gains with while still not regressing other
storage configurations.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
As generic_make_request() is now able to handle arbitrarily sized bios,
it's no longer necessary for each individual block driver to define its
own ->merge_bvec_fn() callback. Remove every invocation completely.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: drbd-user@lists.linbit.com
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@kernel.org>
Cc: ceph-devel@vger.kernel.org
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Neil Brown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: NeilBrown <neilb@suse.de> (for the 'md' bits)
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[dpark: also remove ->merge_bvec_fn() in dm-thin as well as
dm-era-target, and resolve merge conflicts]
Signed-off-by: Dongsu Park <dpark@posteo.net>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The way the block layer is currently written, it goes to great lengths
to avoid having to split bios; upper layer code (such as bio_add_page())
checks what the underlying device can handle and tries to always create
bios that don't need to be split.
But this approach becomes unwieldy and eventually breaks down with
stacked devices and devices with dynamic limits, and it adds a lot of
complexity. If the block layer could split bios as needed, we could
eliminate a lot of complexity elsewhere - particularly in stacked
drivers. Code that creates bios can then create whatever size bios are
convenient, and more importantly stacked drivers don't have to deal with
both their own bio size limitations and the limitations of the
(potentially multiple) devices underneath them. In the future this will
let us delete merge_bvec_fn and a bunch of other code.
We do this by adding calls to blk_queue_split() to the various
make_request functions that need it - a few can already handle arbitrary
size bios. Note that we add the call _after_ any call to
blk_queue_bounce(); this means that blk_queue_split() and
blk_recalc_rq_segments() don't need to be concerned with bouncing
affecting segment merging.
Some make_request_fn() callbacks were simple enough to audit and verify
they don't need blk_queue_split() calls. The skipped ones are:
* nfhd_make_request (arch/m68k/emu/nfblock.c)
* axon_ram_make_request (arch/powerpc/sysdev/axonram.c)
* simdisk_make_request (arch/xtensa/platforms/iss/simdisk.c)
* brd_make_request (ramdisk - drivers/block/brd.c)
* mtip_submit_request (drivers/block/mtip32xx/mtip32xx.c)
* loop_make_request
* null_queue_bio
* bcache's make_request fns
Some others are almost certainly safe to remove now, but will be left
for future patches.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: drbd-user@lists.linbit.com
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Jim Paris <jim@jtan.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Acked-by: NeilBrown <neilb@suse.de> (for the 'md/md.c' bits)
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[dpark: skip more mq-based drivers, resolve merge conflicts, etc.]
Signed-off-by: Dongsu Park <dpark@posteo.net>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Lots of devices support huge discard sizes these days. Depending
on how the device handles them internally, huge discards can
introduce massive latencies (hundreds of msec) on the device side.
We have a sysfs file, discard_max_bytes, that advertises the max
hardware supported discard size. Make this writeable, and split
the settings into a soft and hard limit. This can be set from
'discard_granularity' and up to the hardware limit.
Add a new sysfs file, 'discard_max_hw_bytes', that shows the hw
set limit.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
ability to handle partial request completions -- otherwise with the
current SCSI LLDs these changes could lead to silent data corruption.
- Fix two DM version bumps that were missing from the initial 4.2 DM
pull request (enabled userspace lvm2 to know certain changes have been
made).
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Merge tag 'dm-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
"Apologies for not pressing this request-based DM partial completion
issue further, it was an oversight on my part. We'll have to get it
fixed up properly and revisit for a future release.
- Revert block and DM core changes the removed request-based DM's
ability to handle partial request completions -- otherwise with the
current SCSI LLDs these changes could lead to silent data
corruption.
- Fix two DM version bumps that were missing from the initial 4.2 DM
pull request (enabled userspace lvm2 to know certain changes have
been made)"
* tag 'dm-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache policy smq: fix "default" version to be 1.4.0
dm: bump the ioctl version to 4.32.0
Revert "block, dm: don't copy bios for request clones"
Revert "dm: do not allocate any mempools for blk-mq request-based DM"
This reverts commit 5f1b670d0b.
Justification for revert as reported in this dm-devel post:
https://www.redhat.com/archives/dm-devel/2015-June/msg00160.html
this change should not be pushed to mainline yet.
Firstly, Christoph has a newer version of the patch that fixes silent
data corruption problem:
https://www.redhat.com/archives/dm-devel/2015-May/msg00229.html
And the new version still depends on LLDDs to always complete requests
to the end when error happens, while block API doesn't enforce such a
requirement. If the assumption is ever broken, the inconsistency between
request and bio (e.g. rq->__sector and rq->bio) will cause silent data
corruption:
https://www.redhat.com/archives/dm-devel/2015-June/msg00022.html
Reported-by: Junichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull cgroup writeback support from Jens Axboe:
"This is the big pull request for adding cgroup writeback support.
This code has been in development for a long time, and it has been
simmering in for-next for a good chunk of this cycle too. This is one
of those problems that has been talked about for at least half a
decade, finally there's a solution and code to go with it.
Also see last weeks writeup on LWN:
http://lwn.net/Articles/648292/"
* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
writeback, blkio: add documentation for cgroup writeback support
vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
writeback: do foreign inode detection iff cgroup writeback is enabled
v9fs: fix error handling in v9fs_session_init()
bdi: fix wrong error return value in cgwb_create()
buffer: remove unusued 'ret' variable
writeback: disassociate inodes from dying bdi_writebacks
writeback: implement foreign cgroup inode bdi_writeback switching
writeback: add lockdep annotation to inode_to_wb()
writeback: use unlocked_inode_to_wb transaction in inode_congested()
writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
writeback: implement [locked_]inode_to_wb_and_lock_list()
writeback: implement foreign cgroup inode detection
writeback: make writeback_control track the inode being written back
writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
writeback: implement memcg writeback domain based throttling
writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
writeback: implement memcg wb_domain
writeback: update wb_over_bg_thresh() to use wb_domain aware operations
...
Pull asm/scatterlist.h removal from Jens Axboe:
"We don't have any specific arch scatterlist anymore, since parisc
finally switched over. Kill the include"
* 'for-4.2/sg' of git://git.kernel.dk/linux-block:
remove scatterlist.h generation from arch Kbuild files
remove <asm/scatterlist.h>
Pull core block IO update from Jens Axboe:
"Nothing really major in here, mostly a collection of smaller
optimizations and cleanups, mixed with various fixes. In more detail,
this contains:
- Addition of policy specific data to blkcg for block cgroups. From
Arianna Avanzini.
- Various cleanups around command types from Christoph.
- Cleanup of the suspend block I/O path from Christoph.
- Plugging updates from Shaohua and Jeff Moyer, for blk-mq.
- Eliminating atomic inc/dec of both remaining IO count and reference
count in a bio. From me.
- Fixes for SG gap and chunk size support for data-less (discards)
IO, so we can merge these better. From me.
- Small restructuring of blk-mq shared tag support, freeing drivers
from iterating hardware queues. From Keith Busch.
- A few cfq-iosched tweaks, from Tahsin Erdogan and me. Makes the
IOPS mode the default for non-rotational storage"
* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
cfq-iosched: move group scheduling functions under ifdef
cfq-iosched: fix the setting of IOPS mode on SSDs
blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
block, cgroup: implement policy-specific per-blkcg data
block: Make CFQ default to IOPS mode on SSDs
block: add blk_set_queue_dying() to blkdev.h
blk-mq: Shared tag enhancements
block: don't honor chunk sizes for data-less IO
block: only honor SG gap prevention for merges that contain data
block: fix returnvar.cocci warnings
block, dm: don't copy bios for request clones
block: remove management of bi_remaining when restoring original bi_end_io
block: replace trylock with mutex_lock in blkdev_reread_part()
block: export blkdev_reread_part() and __blkdev_reread_part()
suspend: simplify block I/O handling
block: collapse bio bit space
block: remove unused BIO_RW_BLOCK and BIO_EOF flags
block: remove BIO_EOPNOTSUPP
...
We export this function and NVMe wants to use it, but for some reason
it was never added to the block header. Do that.
Signed-off-by: Jens Axboe <axboe@fb.com>
blk_{set|clear}_queue_congested() take @q and set or clear,
respectively, the congestion state of its bdi's root wb. Because bdi
used to be able to handle congestion state only on the root wb, the
callers of those functions tested whether the congestion is on the
root blkcg and skipped if not.
This is cumbersome and makes implementation of per cgroup
bdi_writeback congestion state propagation difficult. This patch
renames blk_{set|clear}_queue_congested() to
blk_{set|clear}_congested(), and makes them take request_list instead
of request_queue and test whether the specified request_list is the
root one before updating bdi_writeback congestion state. This makes
the tests in the callers unnecessary and simplifies them.
As there are no external users of these functions, the definitions are
moved from include/linux/blkdev.h to block/blk-core.c.
This patch doesn't introduce any noticeable behavior difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.
This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it. c files
which need access to more backing-dev details now include
backing-dev.h directly. This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.
v2: fs/fat build failure fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently dm-multipath has to clone the bios for every request sent
to the lower devices, which wastes cpu cycles and ties down memory.
This patch instead adds a new REQ_CLONE flag that instructs req_bio_endio
to not complete bios attached to a request, which we set on clone
requests similar to bios in a flush sequence. With this change I/O
errors on a path failure only get propagated to dm-multipath, which
can then either resubmit the I/O or complete the bios on the original
request.
I've done some basic testing of this on a Linux target with ALUA support,
and it survives path failures during I/O nicely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
lockdep gets unhappy about the not disabling irqs when using the queue_lock
around it. Instead of trying to fix that up just switch to an atomic_t
and get rid of the lock.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
With commit ff36ab345 ("dm: remove request-based logic from
make_request_fn wrapper") DM no longer calls blk_queue_bio() directly,
so remove its export. Doing so required a forward declaration in
blk-core.c.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This removes the request types and hacks from the block code and into the
old IDE driver. There is a small amunt of code duplication due to this,
but it's not too bad.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
These values are only used by the IDE driver, so move them into it
by allowing drivers to take cmd_type values after the first private
one. Note that we have to turn cmd_type into a plain unsigned integer
so that gcc doesn't complain about mismatching enum types.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
We don't have any arch specific scatterlist now that parisc switched over
to the generic one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Make use of a new interface provided by iov_iter, backed by
scatter-gather list of iovec, instead of the old interface based on
sg_iovec. Also use iov_iter_advance() instead of manual iteration.
This commit should contain only literal replacements, without
functional changes.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
[hch: fixed to do a deep clone of the iov_iter, and to properly use
the iov_iter direction]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit 4ee5eaf4 ("block: add a queue flag for request stacking support")
introduced the concept of "STACKABLE" and blk-mq devices fit the
definition in that they establish q->request_fn. So establish
QUEUE_FLAG_STACKABLE in QUEUE_FLAG_MQ_DEFAULT.
While not strictly needed (DM _could_ just check for q->mq_ops to assume
the device is request-based), request-based DM support for blk-mq devices
benefits from the ability to consistently check for QUEUE_FLAG_STACKABLE
before allowing a device to be stacked into a request-based DM table.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The libata tag allocation is using a round-robin policy. Next patch will
make libata use block generic tag allocation, so let's add a policy to
tag allocation.
Currently two policies: FIFO (default) and round-robin.
Cc: Jens Axboe <axboe@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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>
In order to support accesses to larger chunks of memory, pass in a
'size' parameter (counted in bytes), and return the amount available at
that address.
Add a new helper function, bdev_direct_access(), to handle common
functionality including partition handling, checking the length requested
is positive, checking for the sector being page-aligned, and checking
the length of the request does not pass the end of the partition.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull block driver core update from Jens Axboe:
"This is the pull request for the core block IO changes for 3.19. Not
a huge round this time, mostly lots of little good fixes:
- Fix a bug in sysfs blktrace interface causing a NULL pointer
dereference, when enabled/disabled through that API. From Arianna
Avanzini.
- Various updates/fixes/improvements for blk-mq:
- A set of updates from Bart, mostly fixing buts in the tag
handling.
- Cleanup/code consolidation from Christoph.
- Extend queue_rq API to be able to handle batching issues of IO
requests. NVMe will utilize this shortly. From me.
- A few tag and request handling updates from me.
- Cleanup of the preempt handling for running queues from Paolo.
- Prevent running of unmapped hardware queues from Ming Lei.
- Move the kdump memory limiting check to be in the correct
location, from Shaohua.
- Initialize all software queues at init time from Takashi. This
prevents a kobject warning when CPUs are brought online that
weren't online when a queue was registered.
- Single writeback fix for I_DIRTY clearing from Tejun. Queued with
the core IO changes, since it's just a single fix.
- Version X of the __bio_add_page() segment addition retry from
Maurizio. Hope the Xth time is the charm.
- Documentation fixup for IO scheduler merging from Jan.
- Introduce (and use) generic IO stat accounting helpers for non-rq
drivers, from Gu Zheng.
- Kill off artificial limiting of max sectors in a request from
Christoph"
* 'for-3.19/core' of git://git.kernel.dk/linux-block: (26 commits)
bio: modify __bio_add_page() to accept pages that don't start a new segment
blk-mq: Fix uninitialized kobject at CPU hotplugging
blktrace: don't let the sysfs interface remove trace from running list
blk-mq: Use all available hardware queues
blk-mq: Micro-optimize bt_get()
blk-mq: Fix a race between bt_clear_tag() and bt_get()
blk-mq: Avoid that __bt_get_word() wraps multiple times
blk-mq: Fix a use-after-free
blk-mq: prevent unmapped hw queue from being scheduled
blk-mq: re-check for available tags after running the hardware queue
blk-mq: fix hang in bt_get()
blk-mq: move the kdump check to blk_mq_alloc_tag_set
blk-mq: cleanup tag free handling
blk-mq: use 'nr_cpu_ids' as highest CPU ID count for hwq <-> cpu map
blk: introduce generic io stat accounting help function
blk-mq: handle the single queue case in blk_mq_hctx_next_cpu
genhd: check for int overflow in disk_expand_part_tbl()
blk-mq: add blk_mq_free_hctx_request()
blk-mq: export blk_mq_free_request()
blk-mq: use get_cpu/put_cpu instead of preempt_disable/preempt_enable
...
Jens Axboe