30 Jul, 2012
4 commits
-
This patch adds support for the new VIRTIO_BLK_F_CONFIG_WCE feature,
which exposes the cache mode in the configuration space and lets the
driver modify it. The cache mode is exposed via sysfs.Even if the host does not support the new feature, the cache mode is
visible (thanks to the existing VIRTIO_BLK_F_WCE), but not modifiable.Signed-off-by: Paolo Bonzini
Signed-off-by: Rusty Russell -
Block layer will allocate a spinlock for the queue if the driver does
not provide one in blk_init_queue().The reason to use the internal spinlock is that blk_cleanup_queue() will
switch to use the internal spinlock in the cleanup code path.if (q->queue_lock != &q->__queue_lock)
q->queue_lock = &q->__queue_lock;However, processes which are in D state might have taken the driver
provided spinlock, when the processes wake up, they would release the
block provided spinlock.=====================================
[ BUG: bad unlock balance detected! ]
3.4.0-rc7+ #238 Not tainted
-------------------------------------
fio/3587 is trying to release lock (&(&q->__queue_lock)->rlock) at:
[] blk_queue_bio+0x2a2/0x380
but there are no more locks to release!other info that might help us debug this:
1 lock held by fio/3587:
#0: (&(&vblk->lock)->rlock){......}, at:
[] get_request_wait+0x19a/0x250Other drivers use block layer provided spinlock as well, e.g. SCSI.
Switching to the block layer provided spinlock saves a bit of memory and
does not increase lock contention. Performance test shows no real
difference is observed before and after this patch.Changes in v2: Improve commit log as Michael suggested.
Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He
Acked-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell -
blk_cleanup_queue() will call blk_drian_queue() to drain all the
requests before queue DEAD marking. If we reset the device before
blk_cleanup_queue() the drain would fail.1) if the queue is stopped in do_virtblk_request() because device is
full, the q->request_fn() will not be called.blk_drain_queue() {
while(true) {
...
if (!list_empty(&q->queue_head))
__blk_run_queue(q) {
if (queue is not stoped)
q->request_fn()
}
...
}
}Do no reset the device before blk_cleanup_queue() gives the chance to
start the queue in interrupt handler blk_done().2) In commit b79d866c8b7014a51f611a64c40546109beaf24a, We abort requests
dispatched to driver before blk_cleanup_queue(). There is a race if
requests are dispatched to driver after the abort and before the queue
DEAD mark. To fix this, instead of aborting the requests explicitly, we
can just reset the device after after blk_cleanup_queue so that the
device can complete all the requests before queue DEAD marking in the
drain process.Cc: Rusty Russell
Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He
Acked-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell -
del_gendisk() might not return due to failing to remove the
/sys/block/vda/serial sysfs entry when another thread (udev) is
trying to read it.virtblk_remove()
vdev->config->reset() : guest will not kick us through interrupt
del_gendisk()
device_del()
kobject_del(): got stuck, sysfs entry ref count non zerosysfs_open_file(): user space process read /sys/block/vda/serial
sysfs_get_active() : got sysfs entry ref count
dev_attr_show()
virtblk_serial_show()
blk_execute_rq() : got stuck, interrupt is disabled
request cannot be finishedThis patch fixes it by calling del_gendisk() before we disable guest's
interrupt so that the request sent in virtblk_serial_show() will be
finished and del_gendisk() will success.This fixes another race in hot-unplug process.
It is save to call del_gendisk(vblk->disk) before
flush_work(&vblk->config_work) which might access vblk->disk, because
vblk->disk is not freed until put_disk(vblk->disk).Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He
Acked-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell
22 May, 2012
2 commits
-
Benchmark shows small performance improvement on fusion io device.
Before:
seq-read : io=1,024MB, bw=19,982KB/s, iops=39,964, runt= 52475msec
seq-write: io=1,024MB, bw=20,321KB/s, iops=40,641, runt= 51601msec
rnd-read : io=1,024MB, bw=15,404KB/s, iops=30,808, runt= 68070msec
rnd-write: io=1,024MB, bw=14,776KB/s, iops=29,552, runt= 70963msecAfter:
seq-read : io=1,024MB, bw=20,343KB/s, iops=40,685, runt= 51546msec
seq-write: io=1,024MB, bw=20,803KB/s, iops=41,606, runt= 50404msec
rnd-read : io=1,024MB, bw=16,221KB/s, iops=32,442, runt= 64642msec
rnd-write: io=1,024MB, bw=15,199KB/s, iops=30,397, runt= 68991msecSigned-off-by: Asias He
Signed-off-by: Rusty Russell -
If we reset the virtio-blk device before the requests already dispatched
to the virtio-blk driver from the block layer are finised, we will stuck
in blk_cleanup_queue() and the remove will fail.blk_cleanup_queue() calls blk_drain_queue() to drain all requests queued
before DEAD marking. However it will never success if the device is
already stopped. We'll have q->in_flight[] > 0, so the drain will not
finish.How to reproduce the race:
1. hot-plug a virtio-blk device
2. keep reading/writing the device in guest
3. hot-unplug while the device is busy serving I/OTest:
~1000 rounds of hot-plug/hot-unplug test passed with this patch.Changes in v3:
- Drop blk_abort_queue and blk_abort_request
- Use __blk_end_request_all to complete request dispatched to driverChanges in v2:
- Drop req_in_flight
- Use virtqueue_detach_unused_buf to get request dispatched to driverSigned-off-by: Asias He
Signed-off-by: Rusty Russell
17 Apr, 2012
1 commit
-
Pull virtio fixes from Michael S. Tsirkin:
"Here are some virtio fixes for 3.4: a test build fix, a patch by Ren
fixing naming for systems with a massive number of virtio blk devices,
and balloon fixes for powerpc by David Gibson.There was some discussion about Ren's patch for virtio disc naming:
some people wanted to move the legacy name mangling function to the
block core. But there's no concensus on that yet, and we can always
deduplicate later. Added comments in the hope that this will stop
people from copying this legacy naming scheme into future drivers."* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_balloon: fix handling of PAGE_SIZE != 4k
virtio_balloon: Fix endian bug
virtio_blk: helper function to format disk names
tools/virtio: fix up vhost/test module build
12 Apr, 2012
1 commit
-
The current virtio block's naming algorithm just supports 18278
(26^3 + 26^2 + 26) disks. If there are more virtio blocks,
there will be disks with the same name.Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, add
a function "virtblk_name_format()" for virtio block to support mass
of disks naming.Notes:
- Our naming scheme is ugly. We are stuck with it
for virtio but don't use it for any new driver:
new drivers should name their devices PREFIX%d
where the sequence number can be allocated by ida
- sd_format_disk_name has exactly the same logic.
Moving it to a central place was deferred over worries
that this will make people keep using the legacy naming
in new drivers.
We kept code idential in case someone wants to deduplicate later.Signed-off-by: Ren Mingxin
Acked-by: Asias He
Signed-off-by: Michael S. Tsirkin
29 Mar, 2012
1 commit
-
If a virtio disk is open in guest and a disk resize operation is done,
(virsh blockresize), new size is not visible to tools like "fdisk -l".
This seems to be happening as we update only part->nr_sects and not
bdev->bd_inode size.Call revalidate_disk() which should take care of it. I tested growing disk
size of already open disk and it works for me.Signed-off-by: Vivek Goyal
Signed-off-by: Jens Axboe
15 Jan, 2012
1 commit
-
Introduce a wrapper around scsi_cmd_ioctl that takes a block device.
The function will then be enhanced to detect partition block devices
and, in that case, subject the ioctls to whitelisting.Cc: linux-scsi@vger.kernel.org
Cc: Jens Axboe
Cc: James Bottomley
Signed-off-by: Paolo Bonzini
Signed-off-by: Linus Torvalds
12 Jan, 2012
4 commits
-
Delete the vq and flush any pending requests from the block queue on the
freeze callback to prepare for hibernation.Re-create the vq in the restore callback to resume normal function.
Signed-off-by: Amit Shah
Signed-off-by: Rusty Russell -
The probe and PM restore functions will share this code.
Signed-off-by: Amit Shah
Signed-off-by: Rusty Russell -
Fix a theoretical race related to config work
handler: a config interrupt might happen
after we flush config work but before we
reset the device. It will then cause the
config work to run during or after reset.Two problems with this:
- if this runs after device is gone we will get use after free
- access of config while reset is in progress is racy
(as layout is changing).As a solution
1. flush after reset when we know there will be no more interrupts
2. add a flag to disable config access before resetSigned-off-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell -
Remove wrapper functions. This makes the allocation type explicit in
all callers; I used GPF_KERNEL where it seemed obvious, left it at
GFP_ATOMIC otherwise.Signed-off-by: Rusty Russell
Reviewed-by: Christoph Hellwig
07 Nov, 2011
1 commit
-
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include
net: sch_generic remove redundant use of
net: inet_timewait_sock doesnt need
...Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
02 Nov, 2011
1 commit
-
Based on a patch by Mark Wu
Current index allocation in virtio-blk is based on a monotonically
increasing variable "index". This means we'll run out of numbers
after a while. It also could cause confusion about the disk
name in the case of hot-plugging disks.
Change virtio-blk to use ida to allocate index, instead.Signed-off-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell
01 Nov, 2011
1 commit
-
We want to remove the implicit everywhere presence of module.h
so fix up the people relying on that implicit presence in advance.Signed-off-by: Paul Gortmaker
30 May, 2011
2 commits
-
It is easier to figure out the context by reading SCSI_SENSE_BUFFERSIZE
instead of plain '96'.Signed-off-by: Liu Yuan
Signed-off-by: Rusty Russell -
Wire up the virtio_driver config_changed method to get notified about
config changes raised by the host. For now we just re-read the device
size to support online resizing of devices, but once we add more
attributes that might be changeable they could be added as well.Note that the config_changed method is called from irq context, so
we'll have to use the workqueue infrastructure to provide us a proper
user context for our changes.Signed-off-by: Christoph Hellwig
Signed-off-by: Rusty Russell
23 Oct, 2010
1 commit
-
* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
xen-blkfront: disable barrier/flush write support
Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
block: remove BLKDEV_IFL_WAIT
aic7xxx_old: removed unused 'req' variable
block: remove the BH_Eopnotsupp flag
block: remove the BLKDEV_IFL_BARRIER flag
block: remove the WRITE_BARRIER flag
swap: do not send discards as barriers
fat: do not send discards as barriers
ext4: do not send discards as barriers
jbd2: replace barriers with explicit flush / FUA usage
jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
jbd: replace barriers with explicit flush / FUA usage
nilfs2: replace barriers with explicit flush / FUA usage
reiserfs: replace barriers with explicit flush / FUA usage
gfs2: replace barriers with explicit flush / FUA usage
btrfs: replace barriers with explicit flush / FUA usage
xfs: replace barriers with explicit flush / FUA usage
block: pass gfp_mask and flags to sb_issue_discard
dm: convey that all flushes are processed as empty
...
21 Oct, 2010
1 commit
-
Remove the BKL usage added in "block: push down BKL into .locked_ioctl".
Virtio-blk doesn't use the BKL for anything, and doesn't implement any
ioctl command by itself, but only uses the generic scsi_cmd_ioctl
which is fine without the BKL.Signed-off-by: Christoph Hellwig
Signed-off-by: Rusty Russell
19 Oct, 2010
1 commit
-
Conflicts:
block/blk-core.c
drivers/block/loop.c
mm/swapfile.cSigned-off-by: Jens Axboe
10 Oct, 2010
1 commit
-
Must drop reference taken by blk_make_request().
Signed-off-by: Mike Snitzer
Signed-off-by: Rusty Russell
Cc: stable@kernel.org # .35.x
Signed-off-by: Linus Torvalds
10 Sep, 2010
3 commits
-
Remove now unused REQ_HARDBARRIER support. virtio_blk already
supports REQ_FLUSH and the usefulness of REQ_FUA for virtio_blk is
questionable at this point, so there's nothing else to do to support
new REQ_FLUSH/FUA interface.Signed-off-by: Tejun Heo
Cc: Michael S. Tsirkin
Cc: Christoph Hellwig
Signed-off-by: Jens Axboe -
Barrier is deemed too heavy and will soon be replaced by FLUSH/FUA
requests. Deprecate barrier. All REQ_HARDBARRIERs are failed with
-EOPNOTSUPP and blk_queue_ordered() is replaced with simpler
blk_queue_flush().blk_queue_flush() takes combinations of REQ_FLUSH and FUA. If a
device has write cache and can flush it, it should set REQ_FLUSH. If
the device can handle FUA writes, it should also set REQ_FUA.All blk_queue_ordered() users are converted.
* ORDERED_DRAIN is mapped to 0 which is the default value.
* ORDERED_DRAIN_FLUSH is mapped to REQ_FLUSH.
* ORDERED_DRAIN_FLUSH_FUA is mapped to REQ_FLUSH | REQ_FUA.Signed-off-by: Tejun Heo
Acked-by: Boaz Harrosh
Cc: Christoph Hellwig
Cc: Nick Piggin
Cc: Michael S. Tsirkin
Cc: Jeremy Fitzhardinge
Cc: Chris Wright
Cc: FUJITA Tomonori
Cc: Geert Uytterhoeven
Cc: David S. Miller
Cc: Alasdair G Kergon
Cc: Pierre Ossman
Cc: Stefan Weinhuber
Signed-off-by: Jens Axboe -
Nobody is making meaningful use of ORDERED_BY_TAG now and queue
draining for barrier requests will be removed soon which will render
the advantage of tag ordering moot. Kill ORDERED_BY_TAG. The
following users are affected.* brd: converted to ORDERED_DRAIN.
* virtio_blk: ORDERED_TAG path was already marked deprecated. Removed.
* xen-blkfront: ORDERED_TAG case dropped.Signed-off-by: Tejun Heo
Cc: Christoph Hellwig
Cc: Nick Piggin
Cc: Michael S. Tsirkin
Cc: Jeremy Fitzhardinge
Cc: Chris Wright
Signed-off-by: Jens Axboe
11 Aug, 2010
1 commit
-
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
xen-blkfront: fix missing out label
blkdev: fix blkdev_issue_zeroout return value
block: update request stacking methods to support discards
block: fix missing export of blk_types.h
writeback: fix bad _bh spinlock nesting
drbd: revert "delay probes", feature is being re-implemented differently
drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
drbd: Disable delay probes for the upcomming release
writeback: cleanup bdi_register
writeback: add new tracepoints
writeback: remove unnecessary init_timer call
writeback: optimize periodic bdi thread wakeups
writeback: prevent unnecessary bdi threads wakeups
writeback: move bdi threads exiting logic to the forker thread
writeback: restructure bdi forker loop a little
writeback: move last_active to bdi
writeback: do not remove bdi from bdi_list
writeback: simplify bdi code a little
writeback: do not lose wake-ups in bdi threads
...Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
08 Aug, 2010
5 commits
-
As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.Signed-off-by: Arnd Bergmann
Acked-by: Christoph Hellwig
Signed-off-by: Jens Axboe -
This removes q->prepare_flush_fn completely (changes the
blk_queue_ordered API).Signed-off-by: FUJITA Tomonori
Reviewed-by: Christoph Hellwig
Signed-off-by: Jens Axboe -
use REQ_FLUSH flag instead.
Signed-off-by: FUJITA Tomonori
Cc: Rusty Russell
Reviewed-by: Christoph Hellwig
Signed-off-by: Jens Axboe -
On compilation, gcc correctly detects that we do not handle
all types:In function ‘blk_done’:
warning: enumeration value ‘REQ_TYPE_FS’ not handled in switch
warning: enumeration value ‘REQ_TYPE_SENSE’ not handled in switch
warning: enumeration value ‘REQ_TYPE_PM_SUSPEND’ not handled in switch
warning: enumeration value ‘REQ_TYPE_PM_RESUME’ not handled in switch
warning: enumeration value ‘REQ_TYPE_PM_SHUTDOWN’ not handled in switch
warning: enumeration value ‘REQ_TYPE_LINUX_BLOCK’ not handled in switch
warning: enumeration value ‘REQ_TYPE_ATA_TASKFILE’ not handled in switch
warning: enumeration value ‘REQ_TYPE_ATA_PC’ not handled in switchwhich is a bit pointless since this is at the end of the request
processessing. Add a default case that just breaks out.Signed-off-by: Jens Axboe
-
Remove all the trivial wrappers for the cmd_type and cmd_flags fields in
struct requests. This allows much easier grepping for different request
types instead of unwinding through macros.Signed-off-by: Christoph Hellwig
Signed-off-by: Jens Axboe
05 Aug, 2010
3 commits
-
With the availablility of a sysfs device attribute for examining disk serial
numbers the ioctl is no longer needed. The user-space changes for this aren't
upstream yet so we don't have any users to worry about.Signed-off-by: Ryan Harper
Signed-off-by: Rusty Russell -
Create a new attribute for virtio-blk devices that will fetch the serial number
of the block device. This attribute can be used by udev to create disk/by-id
symlinks for devices that don't have a UUID (filesystem) associated with them.ATA_IDENTIFY strings are special in that they can be up to 20 chars long
and aren't required to be nul-terminated. The buffer is also zero-padded
meaning that if the serial is 19 chars or less that we get a nul-terminated
string. When copying this value into a string buffer, we must be careful to
copy up to the nul (if it present) and only 20 if it is longer and not to
attempt to nul terminate; this isn't needed.Changes since v1:
- Added BUILD_BUG_ON() for PAGE_SIZE check
- Removed min() since BUILD_BUG_ON() handles the check
- Replaced serial_sysfs() by copying id directly to bufferSigned-off-by: Ryan Harper
Signed-off-by: john cooper
Signed-off-by: Rusty Russell -
If we want to support barriers with the cache=writethrough mode in qemu
we need to tell the block layer that we only need queue drains to
implement a barrier. Follow the model set by SCSI and IDE and assume
that there is no volatile write cache if the host doesn't advertize it.
While this might imply working barriers on old qemu versions or other
hypervisors that actually have a volatile write cache this is only a
cosmetic issue - these hypervisors don't guarantee any data integrity
with or without this patch, but with the patch we at least provide
data ordering.Signed-off-by: Christoph Hellwig
Signed-off-by: Rusty Russell
03 Jun, 2010
1 commit
-
We need at least one S/G element to operate properly, as does the block
layer which increments it to one anyway. We hit this due to a qemu
bug which advertises a sg_elements of 0 under some circumstances.Signed-off-by: Christoph Hellwig
Signed-off-by: Rusty Russell (tweaked logic)
19 May, 2010
4 commits
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Switch virtio_blk to new virtqueue_xxx wrappers.
Signed-off-by: Michael S. Tsirkin
Signed-off-by: Rusty Russell -
drivers/block/virtio_blk.c:228:13: warning: multi-character character constant
Signed-off-by: Rusty Russell
Cc: john cooper -
Return serial string to the guest application via
ioctl driver call.Note this form of interface to the guest userland
was the consensus when the prior version using
the ATA_IDENTIFY came under dispute.Signed-off-by: john cooper
Signed-off-by: Rusty Russell -
Add virtio-blk device id (s/n) support via virtio request.
Signed-off-by: john cooper
Signed-off-by: Rusty Russell
