Javier González [Fri, 1 Jun 2018 14:41:14 +0000 (16:41 +0200)]
lightnvm: pblk: take bitmap alloc. out of critical section
pblk allocates line bitmaps within the line lock unnecessarily. In order
to take pressure out of the fast patch, allocate line bitmaps outside
of this lock and refactor accordingly.
Hans Holmberg [Fri, 1 Jun 2018 14:41:13 +0000 (16:41 +0200)]
lightnvm: pblk: kick writer on new flush points
Unless we kick the writer directly when setting a new flush point, the
user risks having to wait for up to one second (the default timeout for
the write thread to be kicked) for the IO to complete.
Hans Holmberg [Fri, 1 Jun 2018 14:41:12 +0000 (16:41 +0200)]
lightnvm: pblk: only try to recover lines with written smeta
When switching between different lun configurations, there is no
guarantee that all lines that contain closed/open chunks have some
valid data to recover.
Check that the smeta chunk has been written to instead. Also
skip bad lines (that does not have enough good chunks).
Javier González [Fri, 1 Jun 2018 14:41:11 +0000 (16:41 +0200)]
lightnvm: pblk: remove unnecessary bio_get/put
In the read path, pblk gets a reference to the incoming bio and puts it
after ending the bio. Though this behavior is correct, it is unnecessary
since pblk is the one putting the bio, therefore, it cannot disappear
underneath it.
Removing this reference, allows to clean up rqd->bio and avoids pointer
bouncing for the different read paths. Now, the incoming bio always
resides in the read context and pblk's internal bios (if any) reside in
rqd->bio.
lightnvm: pblk: add possibility to set write buffer size manually
In some cases, users can want set write buffer size manually, e.g. to
adjust it to specific workload. This patch provides the possibility
to set write buffer size via module parameter feature.
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com> Signed-off-by: Igor Konopko <igor.j.konopko@intel.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Igor Konopko [Fri, 1 Jun 2018 14:41:08 +0000 (16:41 +0200)]
lightnvm: proper error handling for pblk_bio_add_pages
Currently in case of error caused by bio_pc_add_page in
pblk_bio_add_pages two issues occur when calling from
pblk_rb_read_to_bio(). First one is in pblk_bio_free_pages, since we
are trying to free pages not allocated from our mempool. Second one
is the warn from dma_pool_free, that we are trying to free NULL
pointer dma.
This commit fix both issues.
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com> Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Hans Holmberg [Fri, 1 Jun 2018 14:41:07 +0000 (16:41 +0200)]
lightnvm: pblk: fix smeta write error path
Smeta write errors were previously ignored. Skip these
lines instead and throw them back on the free
list, so the chunks will go through a reset cycle
before we attempt to use the line again.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com> Reviewed-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Hans Holmberg [Fri, 1 Jun 2018 14:41:06 +0000 (16:41 +0200)]
lightnvm: pblk: garbage collect lines with failed writes
Write failures should not happen under normal circumstances,
so in order to bring the chunk back into a known state as soon
as possible, evacuate all the valid data out of the line and let the
fw judge if the block can be written to in the next reset cycle.
Do this by introducing a new gc list for lines with failed writes,
and ensure that the rate limiter allocates a small portion of
the write bandwidth to get the job done.
The lba list is saved in memory for use during gc as we
cannot gurantee that the emeta data is readable if a write
error occurred.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com> Reviewed-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Hans Holmberg [Fri, 1 Jun 2018 14:41:05 +0000 (16:41 +0200)]
lightnvm: pblk: rework write error recovery path
The write error recovery path is incomplete, so rework
the write error recovery handling to do resubmits directly
from the write buffer.
When a write error occurs, the remaining sectors in the chunk are
mapped out and invalidated and the request inserted in a resubmit list.
The writer thread checks if there are any requests to resubmit,
scans and invalidates any lbas that have been overwritten by later
writes and resubmits the failed entries.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com> Reviewed-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Javier González [Fri, 1 Jun 2018 13:04:24 +0000 (15:04 +0200)]
lightnvm: pass flag on graceful teardown to targets
If the namespace is unregistered before the LightNVM target is removed
(e.g., on hot unplug) it is too late for the target to store any metadata
on the device - any attempt to write to the device will fail. In this
case, pass on a "gracefull teardown" flag to the target to let it know
when this happens.
In the case of pblk, we pad the open line (close all open chunks) to
improve data retention. In the event of an ungraceful shutdown, avoid
this part and just clean up.
Javier González [Fri, 1 Jun 2018 13:04:19 +0000 (15:04 +0200)]
lightnvm: pblk: warn in case of corrupted write buffer
When cleaning up buffer entries as we wrap up, their state should be
"completed". If any of the entries is in "submitted" state, it means
that something bad has happened. Trigger a warning immediately instead of
waiting for the state flag to eventually be updated, thus hiding the
issue.
Javier González [Fri, 1 Jun 2018 13:04:18 +0000 (15:04 +0200)]
lightnvm: pblk: improve error msg on corrupted LBAs
In the event of a mismatch between the read LBA and the metadata pointer
reported by the device, improve the error message to be able to detect
the offending physical address (PPA) mapped to the corrupted LBA.
Javier González [Fri, 1 Jun 2018 13:04:17 +0000 (15:04 +0200)]
lightnvm: pblk: check read lba on gc path
Check that the lba stored in the LBA metadata is correct in the GC path
too. This requires a new helper function to check random reads in the
vector read.
Javier González [Fri, 1 Jun 2018 13:04:16 +0000 (15:04 +0200)]
lightnvm: pblk: recheck for bad lines at runtime
Bad blocks can grow at runtime. Check that the number of valid blocks in
a line are within the sanity threshold before allocating the line for
new writes.
Jens Axboe [Fri, 1 Jun 2018 13:39:48 +0000 (07:39 -0600)]
Merge branch 'nvme-4.18' of git://git.infradead.org/nvme into for-4.18/block
Pull NVMe changes from Christoph:
"Below is another set of NVMe updates for 4.18. Besides the usual bug
fixes this includes more feature completness in terms of AEN and log
page handling on the target."
* 'nvme-4.18' of git://git.infradead.org/nvme:
nvme: use the changed namespaces list log to clear ns data changed AENs
nvme: mark nvme_queue_scan static
nvme: submit AEN event configuration on startup
nvmet: mask pending AENs
nvmet: add AEN configuration support
nvmet: implement the changed namespaces log
nvmet: split log page implementation
nvmet: add a new nvmet_zero_sgl helper
nvme.h: add AEN configuration symbols
nvme.h: add the changed namespace list log
nvme.h: untangle AEN notice definitions
nvmet: fix error return code in nvmet_file_ns_enable()
nvmet: fix a typo in nvmet_file_ns_enable()
nvme-fabrics: allow internal passthrough command on deleting controllers
nvme-loop: add support for multiple ports
nvme-pci: simplify __nvme_submit_cmd
nvme-pci: Rate limit the nvme timeout warnings
nvme: allow duplicate controller if prior controller being deleted
There is almost no shared logic, which leads to a very confusing code
flow.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Both callers take just around so function call, so move it in.
Also remove the now pointless blk_mq_sched_init wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: remove the always unused name argument to elevator_init
Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
These are only used by the block core. Also move the declarations to
block/blk.h.
Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: move initialization of elevator-related fields to blk_alloc_queue_node
No point in doing this in elevator_init.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvme: use the changed namespaces list log to clear ns data changed AENs
Per section 5.2 we need to issue the corresponding log page to clear an
AEN, so for a namespace data changed AEN we need to read the changed
namespace list log. And once we read that log anyway we might as well
use it to optimize the rescan.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
"When the controller posts a completion queue entry for an outstanding
Asynchronous Event Request command and thus reports an asynchronous
event, subsequent events of that event type are automatically masked by
the controller until the host clears that event. An event is cleared by
reading the log page associated with that event using the Get Log Page
command (see section 5.14)."
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
AEN configuration via the 'Get Features' and 'Set Features' admin
command is mandatory, so we should be implemeting handling for it.
Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: use WRITE_ONCE, check for invalid values] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Remove the common code to allocate a buffer and copy it into the SGL.
Instead the two no-op implementations just zero the SGL directly, and
the smart log allocates a buffer on its own. This prepares for the
more elaborate ANA log page.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Hannes Reinecke [Fri, 25 May 2018 15:34:00 +0000 (17:34 +0200)]
nvme.h: add AEN configuration symbols
Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Davide Sapienza [Thu, 31 May 2018 14:45:08 +0000 (16:45 +0200)]
block, bfq: prevent soft_rt_next_start from being stuck at infinity
BFQ can deem a bfq_queue as soft real-time only if the queue
- periodically becomes completely idle, i.e., empty and with
no still-outstanding I/O request;
- after becoming idle, gets new I/O only after a special reference
time soft_rt_next_start.
In this respect, after commit "block, bfq: consider also past I/O in
soft real-time detection", the value of soft_rt_next_start can never
decrease. This causes a problem with the following special updating
case for soft_rt_next_start: to prevent queues that are not completely
idle to be wrongly detected as soft real-time (when they become
non-empty again), soft_rt_next_start is temporarily set to infinity
for empty queues with still outstanding I/O requests. But, if such an
update is actually performed, then, because of the above commit,
soft_rt_next_start will be stuck at infinity forever, and the queue
will have no more chance to be considered soft real-time.
On slow systems, this problem does cause actual soft real-time
applications to be occasionally not detected as such.
This commit addresses this issue by eliminating the pushing of
soft_rt_next_start to infinity, and by changing the way non-empty
queues are prevented from being wrongly detected as soft
real-time. Simply, a queue that becomes non-empty again can now be
detected as soft real-time only if it has no outstanding I/O request.
Davide Sapienza [Thu, 31 May 2018 14:45:07 +0000 (16:45 +0200)]
block, bfq: increase weight-raising duration for interactive apps
The maximum possible duration of the weight-raising period for
interactive applications is limited to 13 seconds, as this is the time
needed to load the largest application that we considered when tuning
weight raising. Unfortunately, in such an evaluation, we did not
consider the case of very slow virtual machines.
For example, on a QEMU/KVM virtual machine
- running in a slow PC;
- with a virtual disk stacked on a slow low-end 5400rpm HDD;
- serving a heavy I/O workload, such as the sequential reading of
several files;
mplayer takes 23 seconds to start, if constantly weight-raised.
To address this issue, this commit conservatively sets the upper limit
for weight-raising duration to 25 seconds.
Paolo Valente [Thu, 31 May 2018 14:45:06 +0000 (16:45 +0200)]
block, bfq: remove slow-system class
BFQ computes the duration of weight raising for interactive
applications automatically, using some reference parameters. In
particular, BFQ uses the best durations (see comments in the code for
how these durations have been assessed) for two classes of systems:
slow and fast ones. Examples of slow systems are old phones or systems
using micro HDDs. Fast systems are all the remaining ones. Using these
parameters, BFQ computes the actual duration of the weight raising,
for the system at hand, as a function of the relative speed of the
system w.r.t. the speed of a reference system, belonging to the same
class of systems as the system at hand.
This slow vs fast differentiation proved to be useful in the past, but
happens to have little meaning with current hardware. Even worse, it
does cause problems in virtual systems, where the speed of the system
can vary frequently, and so widely to just confuse the class-detection
mechanism, and, as we have verified experimentally, to cause BFQ to
compute non-sensical weight-raising durations.
This commit addresses this issue by removing the slow class and the
class-detection mechanism.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Paolo Valente [Thu, 31 May 2018 14:45:05 +0000 (16:45 +0200)]
block, bfq: add description of weight-raising heuristics
A description of how weight raising works is missing in BFQ
sources. In addition, the code for handling weight raising is
scattered across a few functions. This makes it rather hard to
understand the mechanism and its rationale. This commits adds such a
description at the beginning of the main source file.
Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Filippo Muzzini [Thu, 31 May 2018 13:23:13 +0000 (15:23 +0200)]
block, bfq: remove the removal of 'next' rq in bfq_requests_merged
Since bfq_finish_request() is always called on the request 'next',
after bfq_requests_merged() is finished, and bfq_finish_request()
removes 'next' from its bfq_queue if needed, it isn't necessary to do
such a removal in advance in bfq_merged_requests().
This commit removes such a useless 'next' removal.
Paolo Valente [Thu, 31 May 2018 14:48:05 +0000 (08:48 -0600)]
block, bfq: remove wrong check in bfq_requests_merged
The request rq passed to the function bfq_requests_merged is always in
a bfq_queue, so the check !RB_EMPTY_NODE(&rq->rb_node) at the
beginning of bfq_requests_merged always succeeds, and the control
flow systematically skips to the end of the function. This implies
that the body of the function is never executed, i.e., the
repositioning of rq is never performed.
On the opposite end, a control is missing in the body of the function:
'next' must be removed only if it is inside a bfq_queue.
This commit removes the wrong check on rq, and adds the missing check
on 'next'. In addition, this commit adds comments on
bfq_requests_merged.
Filippo Muzzini [Thu, 31 May 2018 13:23:11 +0000 (15:23 +0200)]
block, bfq: remove wrong lock in bfq_requests_merged
In bfq_requests_merged(), there is a deadlock because the lock on
bfqq->bfqd->lock is held by the calling function, but the code of
this function tries to grab the lock again.
This deadlock is currently hidden by another bug (fixed by next commit
for this source file), which causes the body of bfq_requests_merged()
to be never executed.
This commit removes the deadlock by removing the lock/unlock pair.
Kent Overstreet [Sun, 20 May 2018 22:25:57 +0000 (18:25 -0400)]
xfs: convert to bioset_init()/mempool_init()
Convert XFS to embedded bio sets.
Acked-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk-mq: only iterate over inflight requests in blk_mq_tagset_busy_iter
We already check for started commands in all callbacks, but we should
also protect against already completed commands. Do this by taking
the checks to common code.
Acked-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Kevin Vigor [Wed, 30 May 2018 16:45:11 +0000 (10:45 -0600)]
nbd: clear DISCONNECT_REQUESTED flag once disconnection occurs.
When a userspace client requests a NBD device be disconnected, the
DISCONNECT_REQUESTED flag is set. While this flag is set, the driver
will not inform userspace when a connection is closed.
Unfortunately the flag was never cleared, so once a disconnect was
requested the driver would thereafter never tell userspace about a
closed connection. Thus when connections failed due to timeout, no
attempt to reconnect was made and eventually the device would fail.
Fix by clearing the DISCONNECT_REQUESTED flag (and setting the
DISCONNECTED flag) once all connections are closed.
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Kevin Vigor <kvigor@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Jianchao Wang [Wed, 30 May 2018 16:47:40 +0000 (10:47 -0600)]
block: kyber: make kyber more friendly with merging
Currently, kyber is very unfriendly with merging. kyber depends
on ctx rq_list to do merging, however, most of time, it will not
leave any requests in ctx rq_list. This is because even if tokens
of one domain is used up, kyber will try to dispatch requests
from other domain and flush the rq_list there.
To improve this, we setup kyber_ctx_queue (kcq) which is similar
with ctx, but it has rq_lists for different domain and build same
mapping between kcq and khd as the ctx & hctx. Then we could merge,
insert and dispatch for different domains separately. At the same
time, only flush the rq_list of kcq when get domain token successfully.
Then if one domain token is used up, the requests could be left in
the rq_list of that domain and maybe merged with following io.
Following is my test result on machine with 8 cores and NVMe card
INTEL SSDPEKKR128G7
fio size=256m ioengine=libaio iodepth=64 direct=1 numjobs=8
seq/random
+------+---------------------------------------------------------------+
|patch?| bw(MB/s) | iops | slat(usec) | clat(usec) | merge |
+----------------------------------------------------------------------+
| w/o | 606/612 | 151k/153k | 6.89/7.03 | 3349.21/3305.40 | 0/0 |
+----------------------------------------------------------------------+
| w/ | 1083/616 | 277k/154k | 4.93/6.95 | 1830.62/3279.95 | 223k/3k |
+----------------------------------------------------------------------+
When set numjobs to 16, the bw and iops could reach 1662MB/s and 425k
on my platform.
With recent CQ handling improvements we can now move the locking into
__nvme_submit_cmd. Also remove the local tail variable to make the code
more obvious, remove the __ prefix in the name, and fix the comments
describing the function.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Keith Busch [Thu, 24 May 2018 20:34:55 +0000 (14:34 -0600)]
nvme-pci: Rate limit the nvme timeout warnings
The block layer's timeout handling currently prevents drivers from
completing commands outside the timeout callback once blk-mq decides
they've expired. If a device breaks, this could potentially create many
thousands of timed out commands. There's nothing of value to be gleaned
from observing each of those messages, so this patch adds a rate limit
on them.
Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
James Smart [Fri, 25 May 2018 21:02:23 +0000 (14:02 -0700)]
nvme: allow duplicate controller if prior controller being deleted
The current checks for whether a new controller request "matches" an
existing controller ignores controller state and checks identity strings.
There are cases where an existing controller may be in its last steps of
deletion when they are "matched" by a new connection.
Change the behavior so that the new connection ignores controllers that
are deleted.
Signed-off-by: James Smart <james.smart@broadcom.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
block: remove parent device reference from struct bsg_class_device
Bsg holding a reference to the parent device may result in a crash if a
bsg file handle is closed after the parent device driver has unloaded.
Holding a reference is not really needed: the parent device must exist
between bsg_register_queue and bsg_unregister_queue. Before the device
goes away the caller does blk_cleanup_queue so that all in-flight
requests to the device are gone and all new requests cannot pass beyond
the queue. The queue itself is a refcounted object and it will stay
alive with a bsg file.
Based on analysis, previous patch and changelog from Anatoliy Glagolev.
Reported-by: Anatoliy Glagolev <glagolig@gmail.com> Reviewed-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Jens Axboe [Tue, 29 May 2018 18:56:20 +0000 (12:56 -0600)]
Merge branch 'nvme-4.18-2' of git://git.infradead.org/nvme into for-4.18/block
Pull NVMe changes from Christoph:
"Here is the current batch of nvme updates for 4.18, we have a few more
patches in the queue, but I'd like to get this pile into your tree
and linux-next ASAP.
The biggest item is support for file-backed namespaces in the NVMe
target from Chaitanya, in addition to that we mostly small fixes from
all the usual suspects."
* 'nvme-4.18-2' of git://git.infradead.org/nvme:
nvme: fixup memory leak in nvme_init_identify()
nvme: fix KASAN warning when parsing host nqn
nvmet-loop: use nr_phys_segments when map rq to sgl
nvmet-fc: increase LS buffer count per fc port
nvmet: add simple file backed ns support
nvmet: remove duplicate NULL initialization for req->ns
nvmet: make a few error messages more generic
nvme-fabrics: allow duplicate connections to the discovery controller
nvme-fabrics: centralize discovery controller defaults
nvme-fabrics: remove unnecessary controller subnqn validation
nvme-fc: remove setting DNR on exception conditions
nvme-rdma: stop admin queue before freeing it
nvme-pci: Fix AER reset handling
nvme-pci: set nvmeq->cq_vector after alloc cq/sq
nvme: host: core: fix precedence of ternary operator
nvme: fix lockdep warning in nvme_mpath_clear_current_path
Jens Axboe [Tue, 29 May 2018 14:47:57 +0000 (08:47 -0600)]
block: move ->timeout request member
After the recent timeout handling changes, we have two holes in
the struct. Move the timeout near the deadline, killing both,
and moving related members closer together. On my config on
x86-64, this shrinks struct request from 312 to 304 bytes.
libiscsi is the only SCSI code that return BLK_EH_HANDLED, thus trying to
bypass the normal SCSI EH code. We are going to remove this return value
at the block layer, and at least from a quick look it doesn't look too
harmful to try to send an abort for these cases, especially as the first
one should not actually be possible. If this doesn't work out iscsi
will probably need its own eh_strategy_handler instead to just do the
right thing.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
[While this keeps existing behavior it seems to mismatch the comment,
maintainers please chime in!]
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
scsi_transport_fc: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
NVMe always completes the request before returning from ->timeout, either
by polling for it, or by disabling the controller. Return BLK_EH_DONE so
that the block layer doesn't even try to complete it again.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
The BLK_EH_NOT_HANDLED implies nothing happen, but very often that
is not what is happening - instead the driver already completed the
command. Fix the symbolic name to reflect that a little better.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Keith Busch [Tue, 29 May 2018 13:52:28 +0000 (15:52 +0200)]
blk-mq: Remove generation seqeunce
This patch simplifies the timeout handling by relying on the request
reference counting to ensure the iterator is operating on an inflight
and truly timed out request. Since the reference counting prevents the
tag from being reallocated, the block layer no longer needs to prevent
drivers from completing their requests while the timeout handler is
operating on it: a driver completing a request is allowed to proceed to
the next state without additional syncronization with the block layer.
This also removes any need for generation sequence numbers since the
request lifetime is prevented from being reallocated as a new sequence
while timeout handling is operating on it.
To enables this a refcount is added to struct request so that request
users can be sure they're operating on the same request without it
changing while they're processing it. The request's tag won't be
released for reuse until both the timeout handler and the completion
are done with it.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[hch: slight cleanups, added back submission side hctx lock, use cmpxchg
for completions] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Keith Busch [Tue, 29 May 2018 13:52:27 +0000 (15:52 +0200)]
blk-mq: Fix timeout and state order
The block layer had been setting the state to in-flight prior to updating
the timer. This is the wrong order since the timeout handler could observe
the in-flight state with the older timeout, believing the request had
expired when in fact it is just getting started.
Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
As far as I can tell this function can't even be called any more, given
that ATA implements its own eh_strategy_handler with ata_scsi_error, which
never calls ->eh_timed_out.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Andy Shevchenko [Mon, 28 May 2018 07:37:44 +0000 (15:37 +0800)]
bcache: Replace bch_read_string_list() by __sysfs_match_string()
Kernel library has a common function to match user input from sysfs
against an array of strings. Thus, replace bch_read_string_list() by
__sysfs_match_string().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Coly Li <colyli@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Coly Li [Mon, 28 May 2018 07:37:41 +0000 (15:37 +0800)]
bcache: stop bcache device when backing device is offline
Currently bcache does not handle backing device failure, if backing
device is offline and disconnected from system, its bcache device can still
be accessible. If the bcache device is in writeback mode, I/O requests even
can success if the requests hit on cache device. That is to say, when and
how bcache handles offline backing device is undefined.
This patch tries to handle backing device offline in a rather simple way,
- Add cached_dev->status_update_thread kernel thread to update backing
device status in every 1 second.
- Add cached_dev->offline_seconds to record how many seconds the backing
device is observed to be offline. If the backing device is offline for
BACKING_DEV_OFFLINE_TIMEOUT (30) seconds, set dc->io_disable to 1 and
call bcache_device_stop() to stop the bache device which linked to the
offline backing device.
Now if a backing device is offline for BACKING_DEV_OFFLINE_TIMEOUT seconds,
its bcache device will be removed, then user space application writing on
it will get error immediately, and handler the device failure in time.
This patch is quite simple, does not handle more complicated situations.
Once the bcache device is stopped, users need to recovery the backing
device, register and attach it manually.
Changelog:
v3: call wait_for_kthread_stop() before exits kernel thread.
v2: remove "bcache: " prefix when calling pr_warn().
v1: initial version.
Signed-off-by: Coly Li <colyli@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Cc: Michael Lyle <mlyle@lyle.org> Cc: Junhui Tang <tang.junhui@zte.com.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>
nvmet-loop: use nr_phys_segments when map rq to sgl
Use blk_rq_nr_phys_segments() instead of blk_rq_payload_bytes() to check
if a command contains data to me mapped. This fixes the case where
a struct requests contains LBAs, but no data will actually be send,
e.g. the pending Write Zeroes support.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
James Smart [Mon, 21 May 2018 23:27:42 +0000 (16:27 -0700)]
nvmet-fc: increase LS buffer count per fc port
Todays limit on concurrent LS's is very small - 4 buffers. With large
subsystem counts or large numbers of initiators connecting, the limit
may be exceeded.
Raise the LS buffer count to 256.
Signed-off-by: James Smart <james.smart@broadcom.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
This patch adds simple file backed namespace support for NVMeOF target.
The new file io-cmd-file.c is responsible for handling the code for I/O
commands when ns is file backed. Also, we introduce mempools based slow
path using sync I/Os for file backed ns to ensure forward progress under
reclaim.
The old block device based implementation is moved to io-cmd-bdev.c and
use a "nvmet_bdev_" symbol prefix. The enable/disable calls are also
move into the respective files.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: updated changelog, fixed double req->ns lookup in bdev case] Signed-off-by: Christoph Hellwig <hch@lst.de>
projects / kernel.git / log