The following commit:
commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
replaced __do_lo_send_write(), which used ITER_KVEC iterators, with
lo_write_bvec() which uses ITER_BVEC iterators. In this change, though,
the WRITE flag was lost:
- iov_iter_kvec(&from, ITER_KVEC | WRITE, &kvec, 1, len);
+ iov_iter_bvec(&i, ITER_BVEC, bvec, 1, bvec->bv_len);
This flag is necessary for the DAX case because we make decisions based on
whether or not the iterator is a READ or a WRITE in dax_iomap_actor() and
in dax_iomap_rw().
We end up going through this path in configurations where we combine a PMEM
device with 4k sectors, a loopback device and DAX. The consequence of this
missed flag is that what we intend as a write actually turns into a read in
the DAX code, so no data is ever written.
The very simplest test case is to create a loopback device and try and
write a small string to it, then hexdump a few bytes of the device to see
if the write took. Without this patch you read back all zeros, with this
you read back the string you wrote.
For XFS this causes us to fail or panic during the following xfstests:
xfs/074 xfs/078 xfs/216 xfs/217 xfs/250
For ext4 we have a similar issue where writes never happen, but we don't
currently have any xfstests that use loopback and show this issue.
Fix this by restoring the WRITE flag argument to iov_iter_bvec(). This
causes the xfstests to all pass.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Fixes: commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull a xen_blkfront fix from Konrad:
"It has one simple fix for the multi-queue support not showing up after
a block device was detached/re-attached."
* 'stable/for-jens-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen-blkfront: move negotiate_mq to cover all cases of new VBDs
negotiate_mq should happen in all cases of a new VBD being discovered by
xen-blkfront, whether called through _probe() or a hot-attached new VBD
from dom-0 via xenstore. Otherwise, hot-attached new VBDs are left
configured without multi-queue.
Signed-off-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fix a typo in pkt_start_recovery.
Fixes: 74d46992e0 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It seems that the proper value to return in this particular case is the
one contained into variable new_index instead of ret.
Addresses-Coverity-ID: 1465148 ("Copy-paste error")
Fixes: e46c7287b1 ("nbd: add a basic netlink interface")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename get_disk() to get_disk_and_module() to make sure what the
function does. It's not a great name but at least it is now clear that
put_disk() is not it's counterpart.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull ceph updates from Ilya Dryomov:
"Things have been very quiet on the rbd side, as work continues on the
big ticket items slated for the next merge window.
On the CephFS side we have a large number of cap handling
improvements, a fix for our long-standing abuse of ->journal_info in
ceph_readpages() and yet another dentry pointer management patch"
* tag 'ceph-for-4.16-rc1' of git://github.com/ceph/ceph-client:
ceph: improving efficiency of syncfs
libceph: check kstrndup() return value
ceph: try to allocate enough memory for reserved caps
ceph: fix race of queuing delayed caps
ceph: delete unreachable code in ceph_check_caps()
ceph: limit rate of cap import/export error messages
ceph: fix incorrect snaprealm when adding caps
ceph: fix un-balanced fsc->writeback_count update
ceph: track read contexts in ceph_file_info
ceph: avoid dereferencing invalid pointer during cached readdir
ceph: use atomic_t for ceph_inode_info::i_shared_gen
ceph: cleanup traceless reply handling for rename
ceph: voluntarily drop Fx cap for readdir request
ceph: properly drop caps for setattr request
ceph: voluntarily drop Lx cap for link/rename requests
ceph: voluntarily drop Ax cap for requests that create new inode
rbd: whitelist RBD_FEATURE_OPERATIONS feature bit
rbd: don't NULL out ->obj_request in rbd_img_obj_parent_read_full()
rbd: use kmem_cache_zalloc() in rbd_img_request_create()
rbd: obj_request->completion is unused
Pull virtio/vhost updates from Michael Tsirkin:
"virtio, vhost: fixes, cleanups, features
This includes the disk/cache memory stats for for the virtio balloon,
as well as multiple fixes and cleanups"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost: don't hold onto file pointer for VHOST_SET_LOG_FD
vhost: don't hold onto file pointer for VHOST_SET_VRING_ERR
vhost: don't hold onto file pointer for VHOST_SET_VRING_CALL
ringtest: ring.c malloc & memset to calloc
virtio_vop: don't kfree device on register failure
virtio_pci: don't kfree device on register failure
virtio: split device_register into device_initialize and device_add
vhost: remove unused lock check flag in vhost_dev_cleanup()
vhost: Remove the unused variable.
virtio_blk: print capacity at probe time
virtio: make VIRTIO a menuconfig to ease disabling it all
virtio/ringtest: virtio_ring: fix up need_event math
virtio/ringtest: fix up need_event math
virtio: virtio_mmio: make of_device_ids const.
firmware: Use PTR_ERR_OR_ZERO()
virtio-mmio: Use PTR_ERR_OR_ZERO()
vhost/scsi: Improve a size determination in four functions
virtio_balloon: include disk/file caches memory statistics
Pull PCI updates from Bjorn Helgaas:
- skip AER driver error recovery callbacks for correctable errors
reported via ACPI APEI, as we already do for errors reported via the
native path (Tyler Baicar)
- fix DPC shared interrupt handling (Alex Williamson)
- print full DPC interrupt number (Keith Busch)
- enable DPC only if AER is available (Keith Busch)
- simplify DPC code (Bjorn Helgaas)
- calculate ASPM L1 substate parameter instead of hardcoding it (Bjorn
Helgaas)
- enable Latency Tolerance Reporting for ASPM L1 substates (Bjorn
Helgaas)
- move ASPM internal interfaces out of public header (Bjorn Helgaas)
- allow hot-removal of VGA devices (Mika Westerberg)
- speed up unplug and shutdown by assuming Thunderbolt controllers
don't support Command Completed events (Lukas Wunner)
- add AtomicOps support for GPU and Infiniband drivers (Felix Kuehling,
Jay Cornwall)
- expose "ari_enabled" in sysfs to help NIC naming (Stuart Hayes)
- clean up PCI DMA interface usage (Christoph Hellwig)
- remove PCI pool API (replaced with DMA pool) (Romain Perier)
- deprecate pci_get_bus_and_slot(), which assumed PCI domain 0 (Sinan
Kaya)
- move DT PCI code from drivers/of/ to drivers/pci/ (Rob Herring)
- add PCI-specific wrappers for dev_info(), etc (Frederick Lawler)
- remove warnings on sysfs mmap failure (Bjorn Helgaas)
- quiet ROM validation messages (Alex Deucher)
- remove redundant memory alloc failure messages (Markus Elfring)
- fill in types for compile-time VGA and other I/O port resources
(Bjorn Helgaas)
- make "pci=pcie_scan_all" work for Root Ports as well as Downstream
Ports to help AmigaOne X1000 (Bjorn Helgaas)
- add SPDX tags to all PCI files (Bjorn Helgaas)
- quirk Marvell 9128 DMA aliases (Alex Williamson)
- quirk broken INTx disable on Ceton InfiniTV4 (Bjorn Helgaas)
- fix CONFIG_PCI=n build by adding dummy pci_irqd_intx_xlate() (Niklas
Cassel)
- use DMA API to get MSI address for DesignWare IP (Niklas Cassel)
- fix endpoint-mode DMA mask configuration (Kishon Vijay Abraham I)
- fix ARTPEC-6 incorrect IS_ERR() usage (Wei Yongjun)
- add support for ARTPEC-7 SoC (Niklas Cassel)
- add endpoint-mode support for ARTPEC (Niklas Cassel)
- add Cadence PCIe host and endpoint controller driver (Cyrille
Pitchen)
- handle multiple INTx status bits being set in dra7xx (Vignesh R)
- translate dra7xx hwirq range to fix INTD handling (Vignesh R)
- remove deprecated Exynos PHY initialization code (Jaehoon Chung)
- fix MSI erratum workaround for HiSilicon Hip06/Hip07 (Dongdong Liu)
- fix NULL pointer dereference in iProc BCMA driver (Ray Jui)
- fix Keystone interrupt-controller-node lookup (Johan Hovold)
- constify qcom driver structures (Julia Lawall)
- rework Tegra config space mapping to increase space available for
endpoints (Vidya Sagar)
- simplify Tegra driver by using bus->sysdata (Manikanta Maddireddy)
- remove PCI_REASSIGN_ALL_BUS usage on Tegra (Manikanta Maddireddy)
- add support for Global Fabric Manager Server (GFMS) event to
Microsemi Switchtec switch driver (Logan Gunthorpe)
- add IDs for Switchtec PSX 24xG3 and PSX 48xG3 (Kelvin Cao)
* tag 'pci-v4.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (140 commits)
PCI: cadence: Add EndPoint Controller driver for Cadence PCIe controller
dt-bindings: PCI: cadence: Add DT bindings for Cadence PCIe endpoint controller
PCI: endpoint: Fix EPF device name to support multi-function devices
PCI: endpoint: Add the function number as argument to EPC ops
PCI: cadence: Add host driver for Cadence PCIe controller
dt-bindings: PCI: cadence: Add DT bindings for Cadence PCIe host controller
PCI: Add vendor ID for Cadence
PCI: Add generic function to probe PCI host controllers
PCI: generic: fix missing call of pci_free_resource_list()
PCI: OF: Add generic function to parse and allocate PCI resources
PCI: Regroup all PCI related entries into drivers/pci/Makefile
PCI/DPC: Reformat DPC register definitions
PCI/DPC: Add and use DPC Status register field definitions
PCI/DPC: Squash dpc_rp_pio_get_info() into dpc_process_rp_pio_error()
PCI/DPC: Remove unnecessary RP PIO register structs
PCI/DPC: Push dpc->rp_pio_status assignment into dpc_rp_pio_get_info()
PCI/DPC: Squash dpc_rp_pio_print_error() into dpc_rp_pio_get_info()
PCI/DPC: Make RP PIO log size check more generic
PCI/DPC: Rename local "status" to "dpc_status"
PCI/DPC: Squash dpc_rp_pio_print_tlp_header() into dpc_rp_pio_print_error()
...
Pull more block updates from Jens Axboe:
"Most of this is fixes and not new code/features:
- skd fix from Arnd, fixing a build error dependent on sla allocator
type.
- blk-mq scheduler discard merging fixes, one from me and one from
Keith. This fixes a segment miscalculation for blk-mq-sched, where
we mistakenly think two segments are physically contigious even
though the request isn't carrying real data. Also fixes a bio-to-rq
merge case.
- Don't re-set a bit on the buffer_head flags, if it's already set.
This can cause scalability concerns on bigger machines and
workloads. From Kemi Wang.
- Add BLK_STS_DEV_RESOURCE return value to blk-mq, allowing us to
distuingish between a local (device related) resource starvation
and a global one. The latter might happen without IO being in
flight, so it has to be handled a bit differently. From Ming"
* tag 'for-linus-20180204' of git://git.kernel.dk/linux-block:
block: skd: fix incorrect linux/slab_def.h inclusion
buffer: Avoid setting buffer bits that are already set
blk-mq-sched: Enable merging discard bio into request
blk-mq: fix discard merge with scheduler attached
blk-mq: introduce BLK_STS_DEV_RESOURCE
skd includes slab_def.h to get access to the slab cache object size.
However, including this header breaks when we use SLUB or SLOB instead of
the SLAB allocator, since the structure layout is completely different,
as shown by this warning when we build this driver in one of the invalid
configurations with link-time optimizations enabled:
include/linux/slab.h:715:0: error: type of 'kmem_cache_size' does not match original declaration [-Werror=lto-type-mismatch]
unsigned int kmem_cache_size(struct kmem_cache *s);
mm/slab_common.c:77:14: note: 'kmem_cache_size' was previously declared here
unsigned int kmem_cache_size(struct kmem_cache *s)
^
mm/slab_common.c:77:14: note: code may be misoptimized unless -fno-strict-aliasing is used
include/linux/slab.h:147:0: error: type of 'kmem_cache_destroy' does not match original declaration [-Werror=lto-type-mismatch]
void kmem_cache_destroy(struct kmem_cache *);
mm/slab_common.c:858:6: note: 'kmem_cache_destroy' was previously declared here
void kmem_cache_destroy(struct kmem_cache *s)
^
mm/slab_common.c:858:6: note: code may be misoptimized unless -fno-strict-aliasing is used
include/linux/slab.h:140:0: error: type of 'kmem_cache_create' does not match original declaration [-Werror=lto-type-mismatch]
struct kmem_cache *kmem_cache_create(const char *name, size_t size,
mm/slab_common.c:534:1: note: 'kmem_cache_create' was previously declared here
kmem_cache_create(const char *name, size_t size, size_t align,
^
This removes the header inclusion and instead uses the kmem_cache_size()
interface to get the size in a reliable way.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Print the capacity of the block device when the driver is probed. Many
users expect this since SCSI disks (sd) do it. Moreover, kernel dmesg
output is the primary source of troubleshooting information so it's
helpful to include the disk size there.
The capacity is already printed by virtio_blk when a resize event
occurs. Extract the code and reuse it from virtblk_probe().
This patch also adds the block device name to the message so it can be
correlated with a specific device:
virtio_blk virtio0: [vda] 20971520 512-byte logical blocks (10.7 GB/10.0 GiB)
Cc: Rodrigo A B Freire <rfreire@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This status is returned from driver to block layer if device related
resource is unavailable, but driver can guarantee that IO dispatch
will be triggered in future when the resource is available.
Convert some drivers to return BLK_STS_DEV_RESOURCE. Also, if driver
returns BLK_STS_RESOURCE and SCHED_RESTART is set, rerun queue after
a delay (BLK_MQ_DELAY_QUEUE) to avoid IO stalls. BLK_MQ_DELAY_QUEUE is
3 ms because both scsi-mq and nvmefc are using that magic value.
If a driver can make sure there is in-flight IO, it is safe to return
BLK_STS_DEV_RESOURCE because:
1) If all in-flight IOs complete before examining SCHED_RESTART in
blk_mq_dispatch_rq_list(), SCHED_RESTART must be cleared, so queue
is run immediately in this case by blk_mq_dispatch_rq_list();
2) if there is any in-flight IO after/when examining SCHED_RESTART
in blk_mq_dispatch_rq_list():
- if SCHED_RESTART isn't set, queue is run immediately as handled in 1)
- otherwise, this request will be dispatched after any in-flight IO is
completed via blk_mq_sched_restart()
3) if SCHED_RESTART is set concurently in context because of
BLK_STS_RESOURCE, blk_mq_delay_run_hw_queue() will cover the above two
cases and make sure IO hang can be avoided.
One invariant is that queue will be rerun if SCHED_RESTART is set.
Suggested-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull kern_recvmsg reduction from Al Viro:
"kernel_recvmsg() is a set_fs()-using wrapper for sock_recvmsg(). In
all but one case that is not needed - use of ITER_KVEC for ->msg_iter
takes care of the data and does not care about set_fs(). The only
exception is svc_udp_recvfrom() where we want cmsg to be store into
kernel object; everything else can just use sock_recvmsg() and be done
with that.
A followup converting svc_udp_recvfrom() away from set_fs() (and
killing kernel_recvmsg() off) is *NOT* in here - I'd like to hear what
netdev folks think of the approach proposed in that followup)"
* 'work.sock_recvmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
tipc: switch to sock_recvmsg()
smc: switch to sock_recvmsg()
ipvs: switch to sock_recvmsg()
mISDN: switch to sock_recvmsg()
drbd: switch to sock_recvmsg()
lustre lnet_sock_read(): switch to sock_recvmsg()
cfs2: switch to sock_recvmsg()
ncpfs: switch to sock_recvmsg()
dlm: switch to sock_recvmsg()
svc_recvfrom(): switch to sock_recvmsg()
Pull block updates from Jens Axboe:
"This is the main pull request for block IO related changes for the
4.16 kernel. Nothing major in this pull request, but a good amount of
improvements and fixes all over the map. This contains:
- BFQ improvements, fixes, and cleanups from Angelo, Chiara, and
Paolo.
- Support for SMR zones for deadline and mq-deadline from Damien and
Christoph.
- Set of fixes for bcache by way of Michael Lyle, including fixes
from himself, Kent, Rui, Tang, and Coly.
- Series from Matias for lightnvm with fixes from Hans Holmberg,
Javier, and Matias. Mostly centered around pblk, and the removing
rrpc 1.2 in preparation for supporting 2.0.
- A couple of NVMe pull requests from Christoph. Nothing major in
here, just fixes and cleanups, and support for command tracing from
Johannes.
- Support for blk-throttle for tracking reads and writes separately.
From Joseph Qi. A few cleanups/fixes also for blk-throttle from
Weiping.
- Series from Mike Snitzer that enables dm to register its queue more
logically, something that's alwways been problematic on dm since
it's a stacked device.
- Series from Ming cleaning up some of the bio accessor use, in
preparation for supporting multipage bvecs.
- Various fixes from Ming closing up holes around queue mapping and
quiescing.
- BSD partition fix from Richard Narron, fixing a problem where we
can't mount newer (10/11) FreeBSD partitions.
- Series from Tejun reworking blk-mq timeout handling. The previous
scheme relied on atomic bits, but it had races where we would think
a request had timed out if it to reused at the wrong time.
- null_blk now supports faking timeouts, to enable us to better
exercise and test that functionality separately. From me.
- Kill the separate atomic poll bit in the request struct. After
this, we don't use the atomic bits on blk-mq anymore at all. From
me.
- sgl_alloc/free helpers from Bart.
- Heavily contended tag case scalability improvement from me.
- Various little fixes and cleanups from Arnd, Bart, Corentin,
Douglas, Eryu, Goldwyn, and myself"
* 'for-4.16/block' of git://git.kernel.dk/linux-block: (186 commits)
block: remove smart1,2.h
nvme: add tracepoint for nvme_complete_rq
nvme: add tracepoint for nvme_setup_cmd
nvme-pci: introduce RECONNECTING state to mark initializing procedure
nvme-rdma: remove redundant boolean for inline_data
nvme: don't free uuid pointer before printing it
nvme-pci: Suspend queues after deleting them
bsg: use pr_debug instead of hand crafted macros
blk-mq-debugfs: don't allow write on attributes with seq_operations set
nvme-pci: Fix queue double allocations
block: Set BIO_TRACE_COMPLETION on new bio during split
blk-throttle: use queue_is_rq_based
block: Remove kblockd_schedule_delayed_work{,_on}()
blk-mq: Avoid that blk_mq_delay_run_hw_queue() introduces unintended delays
blk-mq: Rename blk_mq_request_direct_issue() into blk_mq_request_issue_directly()
lib/scatterlist: Fix chaining support in sgl_alloc_order()
blk-throttle: track read and write request individually
block: add bdev_read_only() checks to common helpers
block: fail op_is_write() requests to read-only partitions
blk-throttle: export io_serviced_recursive, io_service_bytes_recursive
...
This feature bit restricts older clients from performing certain
maintenance operations against an image (e.g. clone, snap create).
krbd does not perform maintenance operations.
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
If rbd_img_request_submit() fails, parent_request->obj_request is
NULLed out, triggering an assert in rbd_obj_request_put():
rbd_img_request_put(parent_request)
rbd_parent_request_destroy
rbd_obj_request_put(NULL)
Just remove it -- parent_request->obj_request will be put in
rbd_parent_request_destroy().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
smart1,2.h is unused since commit d436641439 ("cpqarray: remove it from the kernel")
Remove it from tree.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
'struct frame' uses two variables to store the sent timestamp - 'struct
timeval' and jiffies. jiffies is used to avoid discrepancies caused by
updates to system time. 'struct timeval' is deprecated because it uses
32-bit representation for seconds which will overflow in year 2038.
This patch does the following:
- Replace the use of 'struct timeval' and jiffies with ktime_t, which
is the recommended type for timestamping
- ktime_t provides both long range (like jiffies) and high resolution
(like timeval). Using ktime_get (monotonic time) instead of wall-clock
time prevents any discprepancies caused by updates to system time.
[updates by Arnd below]
The original patch from Tina never went anywhere as we discussed how
to keep the impact on performance minimal. I've started over now but
arrived at basically the same patch that she had originally, except for
an slightly improved tsince_hr() function. I'm making it more robust
against overflows, and also optimize explicitly for the common case
in which a frame is less than 4.2 seconds old, using only a 32-bit
division in that case.
This should make the new version more efficient than the old code,
since we replace the existing two 32-bit division in do_gettimeofday()
plus one multiplication with a single single 32-bit division in
tsince_hr() and drop the double bookkeeping. It's also more efficient
than the ktime_get_us() API we discussed before, since that would
also rely on multiple divisions.
Link: https://lists.linaro.org/pipermail/y2038/2015-May/000276.html
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Cc: Ed Cashin <ed.cashin@acm.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull ceph fixes from Ilya Dryomov:
"Two rbd fixes for 4.12 and 4.2 issues respectively, marked for
stable"
* tag 'ceph-for-4.15-rc8' of git://github.com/ceph/ceph-client:
rbd: set max_segments to USHRT_MAX
rbd: reacquire lock should update lock owner client id
Selecting FAULT_INJECTION causes a Kconfig warning when CONFIG_DEBUG_KERNEL
is not set:
warning: (BLK_DEV_NULL_BLK && DRM_I915_SELFTEST) selects FAULT_INJECTION which has unmet direct dependencies (DEBUG_KERNEL)
The other drivers that use FAULT_INJECTION tend to have a separate
Kconfig symbol for turning on that feature, so let's do the same
thing here. This may add a bit more complexity than we like, but
it avoids the warning and is more consistent with the rest of the
kernel.
Fixes: 93b570464c ("null_blk: add option for managing IO timeouts")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use the fault injection framework to provide a way for null_blk
to configure timeouts. This only works for queue_mode 1 and 2,
since the bio mode doesn't have code for tracking timeouts.
Let's say you want to have a 10% chance of timing out every
100,000 requests, and for 5 total timeouts, you could do:
modprobe null_blk timeout="100000,10,0,5"
This is useful for adding blktests to test that IO timeouts
are handled appropriately.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is needed to ensure that we actually handle timeouts.
Without it, the queue_mode=1 path will never call blk_add_timer(),
and the queue_mode=2 path will continually just return
EH_RESET_TIMER and we never actually complete the offending request.
This was used to test the new timeout code, and the changes around
killing off REQ_ATOM_COMPLETE.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ross Zwisler
Jens Axboe
Bhavesh Davda
Jiufei Xue
Gustavo A. R. Silva
Jan Kara
Linus Torvalds
Arnd Bergmann
Stefan Hajnoczi
Ming Lei
Ilya Dryomov
Corentin Labbe
Tina Ruchandani