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path: root/drivers/block/drbd
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2017-06-27drbd: Drop unnecessary staticJulia Lawall
Drop static on a local variable, when the variable is initialized before any use, on every possible execution path through the function. The static has no benefit, and dropping it reduces the code size. The semantic patch that fixes this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @bad exists@ position p; identifier x; type T; @@ static T x@p; ... x = <+...x...+> @@ identifier x; expression e; type T; position p != bad.p; @@ -static T x@p; ... when != x when strict ?x = e; // </smpl> The change in code size is indicates by the following output from the size command. before: text data bss dec hex filename 67299 2291 1056 70646 113f6 drivers/block/drbd/drbd_nl.o after: text data bss dec hex filename 67283 2291 1056 70630 113e6 drivers/block/drbd/drbd_nl.o Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27block: don't bother with bounce limits for make_request driversChristoph Hellwig
We only call blk_queue_bounce for request-based drivers, so stop messing with it for make_request based drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-26Merge remote-tracking branch 'jl/locks-4.13' into work.misc-set_fsAl Viro
2017-06-18drbd: use bio_clone_fast() instead of bio_clone()NeilBrown
drbd does not modify the bi_io_vec of the cloned bio, so there is no need to clone that part. So bio_clone_fast() is the better choice. For bio_clone_fast() we need to specify a bio_set. We could use fs_bio_set, which bio_clone() uses, or drbd_md_io_bio_set, which drbd uses for metadata, but it is generally best to avoid sharing bio_sets unless you can be certain that there are no interdependencies. So create a new bio_set, drbd_io_bio_set, and use bio_clone_fast(). Also remove a "XXX cannot fail ???" comment because it definitely cannot fail - bio_clone_fast() doesn't fail if the GFP flags allow for sleeping. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18blk: make the bioset rescue_workqueue optional.NeilBrown
This patch converts bioset_create() to not create a workqueue by default, so alloctions will never trigger punt_bios_to_rescuer(). It also introduces a new flag BIOSET_NEED_RESCUER which tells bioset_create() to preserve the old behavior. All callers of bioset_create() that are inside block device drivers, are given the BIOSET_NEED_RESCUER flag. biosets used by filesystems or other top-level users do not need rescuing as the bio can never be queued behind other bios. This includes fs_bio_set, blkdev_dio_pool, btrfs_bioset, xfs_ioend_bioset, and one allocated by target_core_iblock.c. biosets used by md/raid do not need rescuing as their usage was recently audited and revised to never risk deadlock. It is hoped that most, if not all, of the remaining biosets can end up being the non-rescued version. Reviewed-by: Christoph Hellwig <hch@lst.de> Credit-to: Ming Lei <ming.lei@redhat.com> (minor fixes) Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18blk: replace bioset_create_nobvec() with a flags arg to bioset_create()NeilBrown
"flags" arguments are often seen as good API design as they allow easy extensibility. bioset_create_nobvec() is implemented internally as a variation in flags passed to __bioset_create(). To support future extension, make the internal structure part of the API. i.e. add a 'flags' argument to bioset_create() and discard bioset_create_nobvec(). Note that the bio_split allocations in drivers/md/raid* do not need the bvec mempool - they should have used bioset_create_nobvec(). Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18blk: remove bio_set arg from blk_queue_split()NeilBrown
blk_queue_split() is always called with the last arg being q->bio_split, where 'q' is the first arg. Also blk_queue_split() sometimes uses the passed-in 'bs' and sometimes uses q->bio_split. This is inconsistent and unnecessary. Remove the last arg and always use q->bio_split inside blk_queue_split() Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Credit-to: Javier González <jg@lightnvm.io> (Noticed that lightnvm was missed) Reviewed-by: Javier González <javier@cnexlabs.com> Tested-by: Javier González <javier@cnexlabs.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-09block: switch bios to blk_status_tChristoph Hellwig
Replace bi_error with a new bi_status to allow for a clear conversion. Note that device mapper overloaded bi_error with a private value, which we'll have to keep arround at least for now and thus propagate to a proper blk_status_t value. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-27drbd: ->sendpage() never needed set_fs()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-20Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "A small collection of fixes that should go into this cycle. - a pull request from Christoph for NVMe, which ended up being manually applied to avoid pulling in newer bits in master. Mostly fibre channel fixes from James, but also a few fixes from Jon and Vijay - a pull request from Konrad, with just a single fix for xen-blkback from Gustavo. - a fuseblk bdi fix from Jan, fixing a regression in this series with the dynamic backing devices. - a blktrace fix from Shaohua, replacing sscanf() with kstrtoull(). - a request leak fix for drbd from Lars, fixing a regression in the last series with the kref changes. This will go to stable as well" * 'for-linus' of git://git.kernel.dk/linux-block: nvmet: release the sq ref on rdma read errors nvmet-fc: remove target cpu scheduling flag nvme-fc: stop queues on error detection nvme-fc: require target or discovery role for fc-nvme targets nvme-fc: correct port role bits nvme: unmap CMB and remove sysfs file in reset path blktrace: fix integer parse fuseblk: Fix warning in super_setup_bdi_name() block: xen-blkback: add null check to avoid null pointer dereference drbd: fix request leak introduced by locking/atomic, kref: Kill kref_sub()
2017-05-11drbd: fix request leak introduced by locking/atomic, kref: Kill kref_sub()Lars Ellenberg
When killing kref_sub(), the unconditional additional kref_get() was not properly paired with the necessary kref_put(), causing a leak of struct drbd_requests (~ 224 Bytes) per submitted bio, and breaking DRBD in general, as the destructor of those "drbd_requests" does more than just the mempoll_free(). Fixes: bdfafc4ffdd2 ("locking/atomic, kref: Kill kref_sub()") Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: stable@vger.kernel.org # v4.11 Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-08mm, vmalloc: use __GFP_HIGHMEM implicitlyMichal Hocko
__vmalloc* allows users to provide gfp flags for the underlying allocation. This API is quite popular $ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l 77 The only problem is that many people are not aware that they really want to give __GFP_HIGHMEM along with other flags because there is really no reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages which are mapped to the kernel vmalloc space. About half of users don't use this flag, though. This signals that we make the API unnecessarily too complex. This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM are simplified and drop the flag. Link: http://lkml.kernel.org/r/20170307141020.29107-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Cristopher Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Millar: "Here are some highlights from the 2065 networking commits that happened this development cycle: 1) XDP support for IXGBE (John Fastabend) and thunderx (Sunil Kowuri) 2) Add a generic XDP driver, so that anyone can test XDP even if they lack a networking device whose driver has explicit XDP support (me). 3) Sparc64 now has an eBPF JIT too (me) 4) Add a BPF program testing framework via BPF_PROG_TEST_RUN (Alexei Starovoitov) 5) Make netfitler network namespace teardown less expensive (Florian Westphal) 6) Add symmetric hashing support to nft_hash (Laura Garcia Liebana) 7) Implement NAPI and GRO in netvsc driver (Stephen Hemminger) 8) Support TC flower offload statistics in mlxsw (Arkadi Sharshevsky) 9) Multiqueue support in stmmac driver (Joao Pinto) 10) Remove TCP timewait recycling, it never really could possibly work well in the real world and timestamp randomization really zaps any hint of usability this feature had (Soheil Hassas Yeganeh) 11) Support level3 vs level4 ECMP route hashing in ipv4 (Nikolay Aleksandrov) 12) Add socket busy poll support to epoll (Sridhar Samudrala) 13) Netlink extended ACK support (Johannes Berg, Pablo Neira Ayuso, and several others) 14) IPSEC hw offload infrastructure (Steffen Klassert)" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2065 commits) tipc: refactor function tipc_sk_recv_stream() tipc: refactor function tipc_sk_recvmsg() net: thunderx: Optimize page recycling for XDP net: thunderx: Support for XDP header adjustment net: thunderx: Add support for XDP_TX net: thunderx: Add support for XDP_DROP net: thunderx: Add basic XDP support net: thunderx: Cleanup receive buffer allocation net: thunderx: Optimize CQE_TX handling net: thunderx: Optimize RBDR descriptor handling net: thunderx: Support for page recycling ipx: call ipxitf_put() in ioctl error path net: sched: add helpers to handle extended actions qed*: Fix issues in the ptp filter config implementation. qede: Fix concurrency issue in PTP Tx path processing. stmmac: Add support for SIMATIC IOT2000 platform net: hns: fix ethtool_get_strings overflow in hns driver tcp: fix wraparound issue in tcp_lp bpf, arm64: fix jit branch offset related to ldimm64 bpf, arm64: implement jiting of BPF_XADD ...
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-08block: remove the discard_zeroes_data flagChristoph Hellwig
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can kill this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08drbd: implement REQ_OP_WRITE_ZEROESChristoph Hellwig
It seems like DRBD assumes its on the wire TRIM request always zeroes data. Use that fact to implement REQ_OP_WRITE_ZEROES. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08drbd: make intelligent use of blkdev_issue_zerooutChristoph Hellwig
drbd always wants its discard wire operations to zero the blocks, so use blkdev_issue_zeroout with the BLKDEV_ZERO_UNMAP flag instead of reinventing it poorly. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08block: add a flags argument to (__)blkdev_issue_zerooutChristoph Hellwig
Turn the existing discard flag into a new BLKDEV_ZERO_UNMAP flag with similar semantics, but without referring to diѕcard. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-03-03Merge branch 'WIP.sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull sched.h split-up from Ingo Molnar: "The point of these changes is to significantly reduce the <linux/sched.h> header footprint, to speed up the kernel build and to have a cleaner header structure. After these changes the new <linux/sched.h>'s typical preprocessed size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K lines), which is around 40% faster to build on typical configs. Not much changed from the last version (-v2) posted three weeks ago: I eliminated quirks, backmerged fixes plus I rebased it to an upstream SHA1 from yesterday that includes most changes queued up in -next plus all sched.h changes that were pending from Andrew. I've re-tested the series both on x86 and on cross-arch defconfigs, and did a bisectability test at a number of random points. I tried to test as many build configurations as possible, but some build breakage is probably still left - but it should be mostly limited to architectures that have no cross-compiler binaries available on kernel.org, and non-default configurations" * 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits) sched/headers: Clean up <linux/sched.h> sched/headers: Remove #ifdefs from <linux/sched.h> sched/headers: Remove the <linux/topology.h> include from <linux/sched.h> sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h> sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h> sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h> sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h> sched/headers: Remove <linux/sched.h> from <linux/sched/init.h> sched/core: Remove unused prefetch_stack() sched/headers: Remove <linux/rculist.h> from <linux/sched.h> sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h> sched/headers: Remove <linux/signal.h> from <linux/sched.h> sched/headers: Remove <linux/rwsem.h> from <linux/sched.h> sched/headers: Remove the runqueue_is_locked() prototype sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h> sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h> sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h> sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h> sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h> sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h> ...
2017-03-02Merge branch 'work.sendmsg' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs sendmsg updates from Al Viro: "More sendmsg work. This is a fairly separate isolated stuff (there's a continuation around lustre, but that one was too late to soak in -next), thus the separate pull request" * 'work.sendmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ncpfs: switch to sock_sendmsg() ncpfs: don't mess with manually advancing iovec on send ncpfs: sendmsg does *not* bugger iovec these days ceph_tcp_sendpage(): use ITER_BVEC sendmsg afs_send_pages(): use ITER_BVEC rds: remove dead code ceph: switch to sock_recvmsg() usbip_recv(): switch to sock_recvmsg() iscsi_target: deal with short writes on the tx side [nbd] pass iov_iter to nbd_xmit() [nbd] switch sock_xmit() to sock_{send,recv}msg() [drbd] use sock_sendmsg()
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<uapi/linux/sched/types.h> We are going to move scheduler ABI details to <uapi/linux/sched/types.h>, which will be used from a number of .c files. Create empty placeholder header that maps to <linux/types.h>. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-28Merge branch 'idr-4.11' of git://git.infradead.org/users/willy/linux-daxLinus Torvalds
Pull IDR rewrite from Matthew Wilcox: "The most significant part of the following is the patch to rewrite the IDR & IDA to be clients of the radix tree. But there's much more, including an enhancement of the IDA to be significantly more space efficient, an IDR & IDA test suite, some improvements to the IDR API (and driver changes to take advantage of those improvements), several improvements to the radix tree test suite and RCU annotations. The IDR & IDA rewrite had a good spin in linux-next and Andrew's tree for most of the last cycle. Coupled with the IDR test suite, I feel pretty confident that any remaining bugs are quite hard to hit. 0-day did a great job of watching my git tree and pointing out problems; as it hit them, I added new test-cases to be sure not to be caught the same way twice" Willy goes on to expand a bit on the IDR rewrite rationale: "The radix tree and the IDR use very similar data structures. Merging the two codebases lets us share the memory allocation pools, and results in a net deletion of 500 lines of code. It also opens up the possibility of exposing more of the features of the radix tree to users of the IDR (and I have some interesting patches along those lines waiting for 4.12) It also shrinks the size of the 'struct idr' from 40 bytes to 24 which will shrink a fair few data structures that embed an IDR" * 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: (32 commits) radix tree test suite: Add config option for map shift idr: Add missing __rcu annotations radix-tree: Fix __rcu annotations radix-tree: Add rcu_dereference and rcu_assign_pointer calls radix tree test suite: Run iteration tests for longer radix tree test suite: Fix split/join memory leaks radix tree test suite: Fix leaks in regression2.c radix tree test suite: Fix leaky tests radix tree test suite: Enable address sanitizer radix_tree_iter_resume: Fix out of bounds error radix-tree: Store a pointer to the root in each node radix-tree: Chain preallocated nodes through ->parent radix tree test suite: Dial down verbosity with -v radix tree test suite: Introduce kmalloc_verbose idr: Return the deleted entry from idr_remove radix tree test suite: Build separate binaries for some tests ida: Use exceptional entries for small IDAs ida: Move ida_bitmap to a percpu variable Reimplement IDR and IDA using the radix tree radix-tree: Add radix_tree_iter_delete ...
2017-02-21Merge tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer updates from Jens Axboe: - blk-mq scheduling framework from me and Omar, with a port of the deadline scheduler for this framework. A port of BFQ from Paolo is in the works, and should be ready for 4.12. - Various fixups and improvements to the above scheduling framework from Omar, Paolo, Bart, me, others. - Cleanup of the exported sysfs blk-mq data into debugfs, from Omar. This allows us to export more information that helps debug hangs or performance issues, without cluttering or abusing the sysfs API. - Fixes for the sbitmap code, the scalable bitmap code that was migrated from blk-mq, from Omar. - Removal of the BLOCK_PC support in struct request, and refactoring of carrying SCSI payloads in the block layer. This cleans up the code nicely, and enables us to kill the SCSI specific parts of struct request, shrinking it down nicely. From Christoph mainly, with help from Hannes. - Support for ranged discard requests and discard merging, also from Christoph. - Support for OPAL in the block layer, and for NVMe as well. Mainly from Scott Bauer, with fixes/updates from various others folks. - Error code fixup for gdrom from Christophe. - cciss pci irq allocation cleanup from Christoph. - Making the cdrom device operations read only, from Kees Cook. - Fixes for duplicate bdi registrations and bdi/queue life time problems from Jan and Dan. - Set of fixes and updates for lightnvm, from Matias and Javier. - A few fixes for nbd from Josef, using idr to name devices and a workqueue deadlock fix on receive. Also marks Josef as the current maintainer of nbd. - Fix from Josef, overwriting queue settings when the number of hardware queues is updated for a blk-mq device. - NVMe fix from Keith, ensuring that we don't repeatedly mark and IO aborted, if we didn't end up aborting it. - SG gap merging fix from Ming Lei for block. - Loop fix also from Ming, fixing a race and crash between setting loop status and IO. - Two block race fixes from Tahsin, fixing request list iteration and fixing a race between device registration and udev device add notifiations. - Double free fix from cgroup writeback, from Tejun. - Another double free fix in blkcg, from Hou Tao. - Partition overflow fix for EFI from Alden Tondettar. * tag 'for-4.11/linus-merge-signed' of git://git.kernel.dk/linux-block: (156 commits) nvme: Check for Security send/recv support before issuing commands. block/sed-opal: allocate struct opal_dev dynamically block/sed-opal: tone down not supported warnings block: don't defer flushes on blk-mq + scheduling blk-mq-sched: ask scheduler for work, if we failed dispatching leftovers blk-mq: don't special case flush inserts for blk-mq-sched blk-mq-sched: don't add flushes to the head of requeue queue blk-mq: have blk_mq_dispatch_rq_list() return if we queued IO or not block: do not allow updates through sysfs until registration completes lightnvm: set default lun range when no luns are specified lightnvm: fix off-by-one error on target initialization Maintainers: Modify SED list from nvme to block Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN uapi: sed-opal fix IOW for activate lsp to use correct struct cdrom: Make device operations read-only elevator: fix loading wrong elevator type for blk-mq devices cciss: switch to pci_irq_alloc_vectors block/loop: fix race between I/O and set_status blk-mq-sched: don't hold queue_lock when calling exit_icq block: set make_request_fn manually in blk_mq_update_nr_hw_queues ...
2017-02-13idr: Return the deleted entry from idr_removeMatthew Wilcox
It is a relatively common idiom (8 instances) to first look up an IDR entry, and then remove it from the tree if it is found, possibly doing further operations upon the entry afterwards. If we change idr_remove() to return the removed object, all of these users can save themselves a walk of the IDR tree. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
2017-02-02block: Use pointer to backing_dev_info from request_queueJan Kara
We will want to have struct backing_dev_info allocated separately from struct request_queue. As the first step add pointer to backing_dev_info to request_queue and convert all users touching it. No functional changes in this patch. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-14locking/atomic, kref: Kill kref_sub()Peter Zijlstra
By general sentiment kref_sub() is a bad interface, make it go away. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14locking/atomic, kref: Add kref_read()Peter Zijlstra
Since we need to change the implementation, stop exposing internals. Provide kref_read() to read the current reference count; typically used for debug messages. Kills two anti-patterns: atomic_read(&kref->refcount) kref->refcount.counter Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14locking/atomic, kref: Add KREF_INIT()Peter Zijlstra
Since we need to change the implementation, stop exposing internals. Provide KREF_INIT() to allow static initialization of struct kref. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-26[drbd] use sock_sendmsg()Al Viro
... and keep ->msg_iter through the loop Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-13Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer updates from Jens Axboe: "This is the main block pull request this series. Contrary to previous release, I've kept the core and driver changes in the same branch. We always ended up having dependencies between the two for obvious reasons, so makes more sense to keep them together. That said, I'll probably try and keep more topical branches going forward, especially for cycles that end up being as busy as this one. The major parts of this pull request is: - Improved support for O_DIRECT on block devices, with a small private implementation instead of using the pig that is fs/direct-io.c. From Christoph. - Request completion tracking in a scalable fashion. This is utilized by two components in this pull, the new hybrid polling and the writeback queue throttling code. - Improved support for polling with O_DIRECT, adding a hybrid mode that combines pure polling with an initial sleep. From me. - Support for automatic throttling of writeback queues on the block side. This uses feedback from the device completion latencies to scale the queue on the block side up or down. From me. - Support from SMR drives in the block layer and for SD. From Hannes and Shaun. - Multi-connection support for nbd. From Josef. - Cleanup of request and bio flags, so we have a clear split between which are bio (or rq) private, and which ones are shared. From Christoph. - A set of patches from Bart, that improve how we handle queue stopping and starting in blk-mq. - Support for WRITE_ZEROES from Chaitanya. - Lightnvm updates from Javier/Matias. - Supoort for FC for the nvme-over-fabrics code. From James Smart. - A bunch of fixes from a whole slew of people, too many to name here" * 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits) blk-stat: fix a few cases of missing batch flushing blk-flush: run the queue when inserting blk-mq flush elevator: make the rqhash helpers exported blk-mq: abstract out blk_mq_dispatch_rq_list() helper blk-mq: add blk_mq_start_stopped_hw_queue() block: improve handling of the magic discard payload blk-wbt: don't throttle discard or write zeroes nbd: use dev_err_ratelimited in io path nbd: reset the setup task for NBD_CLEAR_SOCK nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME nvme-fabrics: Add target support for FC transport nvme-fabrics: Add host support for FC transport nvme-fabrics: Add FC transport LLDD api definitions nvme-fabrics: Add FC transport FC-NVME definitions nvme-fabrics: Add FC transport error codes to nvme.h Add type 0x28 NVME type code to scsi fc headers nvme-fabrics: patch target code in prep for FC transport support nvme-fabrics: set sqe.command_id in core not transports parser: add u64 number parser nvme-rdma: align to generic ib_event logging helper ...
2016-11-22block: drbd: remove impossible failure handlingMing Lei
For a non-cloned bio, bio_add_page() only returns failure when the io vec table is full, but in that case, bio->bi_vcnt can't be zero at all. So remove the impossible failure handling. Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-09drbd: Fix kernel_sendmsg() usage - potential NULL derefRichard Weinberger
Don't pass a size larger than iov_len to kernel_sendmsg(). Otherwise it will cause a NULL pointer deref when kernel_sendmsg() returns with rv < size. DRBD as external module has been around in the kernel 2.4 days already. We used to be compatible to 2.4 and very early 2.6 kernels, we used to use rv = sock_sendmsg(sock, &msg, iov.iov_len); then later changed to rv = kernel_sendmsg(sock, &msg, &iov, 1, size); when we should have used rv = kernel_sendmsg(sock, &msg, &iov, 1, iov.iov_len); tcp_sendmsg() used to totally ignore the size parameter. 57be5bd ip: convert tcp_sendmsg() to iov_iter primitives changes that, and exposes our long standing error. Even with this error exposed, to trigger the bug, we would need to have an environment (config or otherwise) causing us to not use sendpage() for larger transfers, a failing connection, and have it fail "just at the right time". Apparently that was unlikely enough for most, so this went unnoticed for years. Still, it is known to trigger at least some of these, and suspected for the others: [0] http://lists.linbit.com/pipermail/drbd-user/2016-July/023112.html [1] http://lists.linbit.com/pipermail/drbd-dev/2016-March/003362.html [2] https://forums.grsecurity.net/viewtopic.php?f=3&t=4546 [3] https://ubuntuforums.org/showthread.php?t=2336150 [4] http://e2.howsolveproblem.com/i/1175162/ This should go into 4.9, and into all stable branches since and including v4.0, which is the first to contain the exposing change. It is correct for all stable branches older than that as well (which contain the DRBD driver; which is 2.6.33 and up). It requires a small "conflict" resolution for v4.4 and earlier, with v4.5 we dropped the comment block immediately preceding the kernel_sendmsg(). Fixes: b411b3637fa7 ("The DRBD driver") Cc: <stable@vger.kernel.org> # 2.6.33.x- Cc: viro@zeniv.linux.org.uk Cc: christoph.lechleitner@iteg.at Cc: wolfgang.glas@iteg.at Reported-by: Christoph Lechleitner <christoph.lechleitner@iteg.at> Tested-by: Christoph Lechleitner <christoph.lechleitner@iteg.at> Signed-off-by: Richard Weinberger <richard@nod.at> [changed oneliner to be "obvious" without context; more verbose message] Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01block,fs: use REQ_* flags directlyChristoph Hellwig
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags directly. Where applicable this also drops usage of the bio_set_op_attrs wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01block: replace REQ_NOIDLE with REQ_IDLEChristoph Hellwig
Noidle should be the default for writes as seen by all the compounds definitions in fs.h using it. In fact only direct I/O really should be using NODILE, so turn the whole flag around to get the defaults right, which will make our life much easier especially onces the WRITE_* defines go away. This assumes all the existing "raw" users of REQ_SYNC for writes want noidle behavior, which seems to be spot on from a quick audit. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-07block: rename bio bi_rw to bi_opfJens Axboe
Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower portion and the op code in the higher portions. This means that old code that relies on manually setting bi_rw is most likely going to be broken. Instead of letting that brokeness linger, rename the member, to force old and out-of-tree code to break at compile time instead of at runtime. No intended functional changes in this commit. Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-02dynamic_debug: only add header when usedLuis de Bethencourt
kernel.h header doesn't directly use dynamic debug, instead we can include it in module.c (which used it via kernel.h). printk.h only uses it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen in that case. Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com [luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h] Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "Assorted cleanups and fixes. Probably the most interesting part long-term is ->d_init() - that will have a bunch of followups in (at least) ceph and lustre, but we'll need to sort the barrier-related rules before it can get used for really non-trivial stuff. Another fun thing is the merge of ->d_iput() callers (dentry_iput() and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all except the one in __d_lookup_lru())" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) fs/dcache.c: avoid soft-lockup in dput() vfs: new d_init method vfs: Update lookup_dcache() comment bdev: get rid of ->bd_inodes Remove last traces of ->sync_page new helper: d_same_name() dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends() vfs: clean up documentation vfs: document ->d_real() vfs: merge .d_select_inode() into .d_real() unify dentry_iput() and dentry_unlink_inode() binfmt_misc: ->s_root is not going anywhere drop redundant ->owner initializations ufs: get rid of redundant checks orangefs: constify inode_operations missed comment updates from ->direct_IO() prototype change file_inode(f)->i_mapping is f->f_mapping trim fsnotify hooks a bit 9p: new helper - v9fs_parent_fid() debugfs: ->d_parent is never NULL or negative ...
2016-07-26Merge branch 'for-4.8/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "This branch also contains core changes. I've come to the conclusion that from 4.9 and forward, I'll be doing just a single branch. We often have dependencies between core and drivers, and it's hard to always split them up appropriately without pulling core into drivers when that happens. That said, this contains: - separate secure erase type for the core block layer, from Christoph. - set of discard fixes, from Christoph. - bio shrinking fixes from Christoph, as a followup up to the op/flags change in the core branch. - map and append request fixes from Christoph. - NVMeF (NVMe over Fabrics) code from Christoph. This is pretty exciting! - nvme-loop fixes from Arnd. - removal of ->driverfs_dev from Dan, after providing a device_add_disk() helper. - bcache fixes from Bhaktipriya and Yijing. - cdrom subchannel read fix from Vchannaiah. - set of lightnvm updates from Wenwei, Matias, Johannes, and Javier. - set of drbd updates and fixes from Fabian, Lars, and Philipp. - mg_disk error path fix from Bart. - user notification for failed device add for loop, from Minfei. - NVMe in general: + NVMe delay quirk from Guilherme. + SR-IOV support and command retry limits from Keith. + fix for memory-less NUMA node from Masayoshi. + use UINT_MAX for discard sectors, from Minfei. + cancel IO fixes from Ming. + don't allocate unused major, from Neil. + error code fixup from Dan. + use constants for PSDT/FUSE from James. + variable init fix from Jay. + fabrics fixes from Ming, Sagi, and Wei. + various fixes" * 'for-4.8/drivers' of git://git.kernel.dk/linux-block: (115 commits) nvme/pci: Provide SR-IOV support nvme: initialize variable before logical OR'ing it block: unexport various bio mapping helpers scsi/osd: open code blk_make_request target: stop using blk_make_request block: simplify and export blk_rq_append_bio block: ensure bios return from blk_get_request are properly initialized virtio_blk: use blk_rq_map_kern memstick: don't allow REQ_TYPE_BLOCK_PC requests block: shrink bio size again block: simplify and cleanup bvec pool handling block: get rid of bio_rw and READA block: don't ignore -EOPNOTSUPP blkdev_issue_write_same block: introduce BLKDEV_DISCARD_ZERO to fix zeroout NVMe: don't allocate unused nvme_major nvme: avoid crashes when node 0 is memoryless node. nvme: Limit command retries loop: Make user notify for adding loop device failed nvme-loop: fix nvme-loop Kconfig dependencies nvmet: fix return value check in nvmet_subsys_alloc() ...
2016-07-20block: get rid of bio_rw and READAChristoph Hellwig
These two are confusing leftover of the old world order, combining values of the REQ_OP_ and REQ_ namespaces. For callers that don't special case we mostly just replace bi_rw with bio_data_dir or op_is_write, except for the few cases where a switch over the REQ_OP_ values makes more sense. Any check for READA is replaced with an explicit check for REQ_RAHEAD. Also remove the READA alias for REQ_RAHEAD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: correctly handle failed crypto_alloc_hashLars Ellenberg
crypto_alloc_hash returns an ERR_PTR(), not NULL. Also reset peer_integrity_tfm to NULL, to not call crypto_free_hash() on an errno in the cleanup path. Reported-by: Insu Yun <wuninsu@gmail.com> Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: al_write_transaction: skip re-scanning of bitmap page pointer arrayLars Ellenberg
For larger devices, the array of bitmap page pointers can grow very large (8000 pointers per TB of storage). For each activity log transaction, we need to flush the associated bitmap pages to stable storage. Currently, we just "mark" the respective pages while setting up the transaction, then tell the bitmap code to write out all marked pages, but skip unchanged pages. But one such transaction can affect only a small number of bitmap pages, there is no need to scan the full array of several (ten-)thousand page pointers to find the few marked ones. Instead, remember the index numbers of the few affected pages, and later only re-check those to skip duplicates and unchanged ones. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: finally report ms, not jiffies, in log messageLars Ellenberg
Also skip the message unless bitmap IO took longer than 5 ms. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: get rid of empty statement in is_valid_stateRoland Kammerer
This should silence a warning about an empty statement. Thanks to Fabian Frederick <fabf@skynet.be> who sent a patch I modified to be smaller and avoids an additional indent level. Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com> Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: code cleanups without semantic changesFabian Frederick
This contains various cosmetic fixes ranging from simple typos to const-ifying, and using booleans properly. Original commit messages from Fabian's patch set: drbd: debugfs: constify drbd_version_fops drbd: use seq_put instead of seq_print where possible drbd: include linux/uaccess.h instead of asm/uaccess.h drbd: use const char * const for drbd strings drbd: kerneldoc warning fix in w_e_end_data_req() drbd: use unsigned for one bit fields drbd: use bool for peer is_ states drbd: fix typo drbd: use | for bitmask combination drbd: use true/false for bool drbd: fix drbd_bm_init() comments drbd: introduce peer state union drbd: fix maybe_pull_ahead() locking comments drbd: use bool for growing drbd: remove redundant declarations drbd: replace if/BUG by BUG_ON Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: bump current uuid when resuming IO with diskless peerLars Ellenberg
Scenario, starting with normal operation Connected Primary/Secondary UpToDate/UpToDate NetworkFailure Primary/Unknown UpToDate/DUnknown (frozen) ... more failures happen, secondary loses it's disk, but eventually is able to re-establish the replication link ... Connected Primary/Secondary UpToDate/Diskless (resumed; needs to bump uuid!) We used to just resume/resent suspended requests, without bumping the UUID. Which will lead to problems later, when we want to re-attach the disk on the peer, without first disconnecting, or if we experience additional failures, because we now have diverging data without being able to recognize it. Make sure we also bump the current data generation UUID, if we notice "peer disk unknown" -> "peer disk known bad". Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: disallow promotion during resync handshake, avoid deadlock and hard resetLars Ellenberg
We already serialize connection state changes, and other, non-connection state changes (role changes) while we are establishing a connection. But if we have an established connection, then trigger a resync handshake (by primary --force or similar), until now we just had to be "lucky". Consider this sequence (e.g. deployment scenario): create-md; up; -> Connected Secondary/Secondary Inconsistent/Inconsistent then do a racy primary --force on both peers. block drbd0: drbd_sync_handshake: block drbd0: self 0000000000000004:0000000000000000:0000000000000000:0000000000000000 bits:25590 flags:0 block drbd0: peer 0000000000000004:0000000000000000:0000000000000000:0000000000000000 bits:25590 flags:0 block drbd0: peer( Unknown -> Secondary ) conn( WFReportParams -> Connected ) pdsk( DUnknown -> Inconsistent ) block drbd0: peer( Secondary -> Primary ) pdsk( Inconsistent -> UpToDate ) *** HERE things go wrong. *** block drbd0: role( Secondary -> Primary ) block drbd0: drbd_sync_handshake: block drbd0: self 0000000000000005:0000000000000000:0000000000000000:0000000000000000 bits:25590 flags:0 block drbd0: peer C90D2FC716D232AB:0000000000000004:0000000000000000:0000000000000000 bits:25590 flags:0 block drbd0: Becoming sync target due to disk states. block drbd0: Writing the whole bitmap, full sync required after drbd_sync_handshake. block drbd0: Remote failed to finish a request within 6007ms > ko-count (2) * timeout (30 * 0.1s) drbd s0: peer( Primary -> Unknown ) conn( Connected -> Timeout ) pdsk( UpToDate -> DUnknown ) The problem here is that the local promotion happens before the sync handshake triggered by the remote promotion was completed. Some assumptions elsewhere become wrong, and when the expected resync handshake is then received and processed, we get stuck in a deadlock, which can only be recovered by reboot :-( Fix: if we know the peer has good data, and our own disk is present, but NOT good, and there is no resync going on yet, we expect a sync handshake to happen "soon". So reject a racy promotion with SS_IN_TRANSIENT_STATE. Result: ... as above ... block drbd0: peer( Secondary -> Primary ) pdsk( Inconsistent -> UpToDate ) *** local promotion being postponed until ... *** block drbd0: drbd_sync_handshake: block drbd0: self 0000000000000004:0000000000000000:0000000000000000:0000000000000000 bits:25590 flags:0 block drbd0: peer 77868BDA836E12A5:0000000000000004:0000000000000000:0000000000000000 bits:25590 flags:0 ... block drbd0: conn( WFBitMapT -> WFSyncUUID ) block drbd0: updated sync uuid 85D06D0E8887AD44:0000000000000000:0000000000000000:0000000000000000 block drbd0: conn( WFSyncUUID -> SyncTarget ) *** ... after the resync handshake *** block drbd0: role( Secondary -> Primary ) Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: sync_handshake: handle identical uuids with current (frozen) PrimaryLars Ellenberg
If in a two-primary scenario, we lost our peer, freeze IO, and are still frozen (no UUID rotation) when the peer comes back as Secondary after a hard crash, we will see identical UUIDs. The "rule_nr = 40" chose to use the "CRASHED_PRIMARY" bit as arbitration, but that would cause the still running (but frozen) Primary to become SyncTarget (which it typically refuses), and the handshake is declined. Fix: check current roles. If we have *one* current primary, the Primary wins. (rule_nr = 41) Since that is a protocol change, use the newly introduced DRBD_FF_WSAME to determine if rule_nr = 41 can be applied. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-13drbd: introduce WRITE_SAME supportLars Ellenberg
We will support WRITE_SAME, if * all peers support WRITE_SAME (both in kernel and DRBD version), * all peer devices support WRITE_SAME * logical_block_size is identical on all peers. We may at some point introduce a fallback on the receiving side for devices/kernels that do not support WRITE_SAME, by open-coding a submit loop. But not yet. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: Jens Axboe <axboe@fb.com>