Commit Graph

182 Commits

Author SHA1 Message Date
Suman Anna 963e16256e virtio: fix memory leak of virtio ida cache layers
commit c13f99b7e945dad5273a8b7ee230f4d1f22d3354 upstream.

The virtio core uses a static ida named virtio_index_ida for
assigning index numbers to virtio devices during registration.
The ida core may allocate some internal idr cache layers and
an ida bitmap upon any ida allocation, and all these layers are
truely freed only upon the ida destruction. The virtio_index_ida
is not destroyed at present, leading to a memory leak when using
the virtio core as a module and atleast one virtio device is
registered and unregistered.

Fix this by invoking ida_destroy() in the virtio core module
exit.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03 15:06:21 -08:00
Michael S. Tsirkin d96f66edf7 virtio_pci: fix virtio spec compliance on restore
commit 6fbc198cf623944ab60a1db6d306a4d55cdd820d upstream.

On restore, virtio pci does the following:
+ set features
+ init vqs etc - device can be used at this point!
+ set ACKNOWLEDGE,DRIVER and DRIVER_OK status bits

This is in violation of the virtio spec, which
requires the following order:
- ACKNOWLEDGE
- DRIVER
- init vqs
- DRIVER_OK

This behaviour will break with hypervisors that assume spec compliant
behaviour.  It seems like a good idea to have this patch applied to
stable branches to reduce the support butden for the hypervisors.

Cc: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-14 08:47:55 -08:00
Rusty Russell 16440b5497 virtio_balloon: don't softlockup on huge balloon changes.
commit 1f74ef0f2d7d692fcd615621e0e734c3e7771413 upstream.

When adding or removing 100G from a balloon:

    BUG: soft lockup - CPU#0 stuck for 22s! [vballoon:367]

We have a wait_event_interruptible(), but the condition is always true
(more ballooning to do) so we don't ever sleep.  We also have a
wait_event() for the host to ack, but that is also always true as QEMU
is synchronous for balloon operations.

Reported-by: Gopesh Kumar Chaudhary <gopchaud@in.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-13 13:59:41 +02:00
Michael S. Tsirkin c23b1ece61 virtio: support unlocked queue poll
[ Upstream commit cc229884d3f77ec3b1240e467e0236c3e0647c0c ]

This adds a way to check ring empty state after enable_cb outside any
locks. Will be used by virtio_net.

Note: there's room for more optimization: caller is likely to have a
memory barrier already, which means we might be able to get rid of a
barrier here.  Deferring this optimization until we do some
benchmarking.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-28 16:29:55 -07:00
Luiz Capitulino ebfc049ce8 virtio_balloon: leak_balloon(): only tell host if we got pages deflated
commit 8c6bab4f3874d31804a00782c48a8f244a0d3cc0 upstream.

balloon_page_dequeue() can return NULL.  If it does for the first page
being freed then leak_balloon() will create a scatter list with len=0.
Which in turn seems to generate an invalid virtio request.

I didn't get this in practice, I found it by code review.  On the other
hand, such an invalid virtio request will cause errors in QEMU and
fill_balloon() also performs the same check implemented by this commit.

This bug was introduced in e2250429.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 14:07:31 -07:00
Rusty Russell 92549abc6a virtio_balloon: use simplified virtqueue accessors.
We never add buffers with input and output parts, so use the new accessors.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 15:45:06 +10:30
Rusty Russell 282edb3649 virtio_ring: virtqueue_add_outbuf / virtqueue_add_inbuf.
These are specialized versions of virtqueue_add_buf(), which cover
over 80% of cases and are far clearer.

In particular, the scatterlists passed to these functions don't have
to be clean (ie. we ignore end markers).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 15:44:52 +10:30
Rusty Russell 13816c768d virtio_ring: virtqueue_add_sgs, to add multiple sgs.
virtio_scsi can really use this, to avoid the current hack of copying
the whole sg array.  Some other things get slightly neater, too.

This causes a slowdown in virtqueue_add_buf(), which is implemented as
a wrapper.  This is addressed in the next patches.

for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers:

Before:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39009-39063(39062)
	Host: notified 39009-39063(39062), pinged 0
	Wall time:1.700000-1.950000(1.723542)

After:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39062-39063(39063)
	Host: notified 39062-39063(39063), pinged 0
	Wall time:1.760000-2.220000(1.789167)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
2013-03-20 15:43:29 +10:30
Rusty Russell a9a0fef779 virtio_ring: expose virtio barriers for use in vringh.
The host side of ring needs this logic too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 14:00:41 +10:30
Linus Torvalds 3c834b6f41 All trivial, thanks to the stuff which didn't quite make it time.
Cheers,
 Rusty.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJRLEkHAAoJENkgDmzRrbjx6K0P/3o9/iW5hkOPYpu+KV2nr0wG
 6RG0uu0DCOb/tckigYwnn5PkS7UEcJu6kDypnEgXfhcNhYiBjoGIAUEQ2jBYyzQm
 IYc4oZhxDdqigJL/FHi2zL50mkWacTdBK83udxim3eRkgW9ysBRoBFwqMruVyhZv
 474KGS4PNT8pHDOCAlrRS1I9oW2pYTuUidN+SnfVJ8gFSkH0tuHEGoJeGrtDa010
 XkiWqiTJq6pDHTM5f4Wwp/WNQ21UNDBlvRahg0nqTZXicQsvujV0Tdb+EnAfXwa+
 bssqvO4X2WqlraVK1TJteufhcdhUgt/I1+45p9eLZvOXizk7EBKxFWynE7C878GV
 dhpz8i4mc+u6aJlGoHzwvKah0zhwDtqWdbDS+LNQjRmjMK9v45ttoisU+iR1GjLt
 JpDVg73K315aWJ9RLsYu7mvZ8JY+qRFkwXqX3lZd+GdohY0DSmGMxMqJG93sLBYi
 42vyHMaBd1JY0rDVqpfzlmjnSxX+k05uB0GYB3fO0CXbPxmfXtRKz7/5wpSz0Up+
 nTCs6Xa7t5jtG9qpC4cKxyEDEwB9M6SSxi+lhrIBkeDqlFwXAv1Fean4jqqhtFwr
 HO6i1mYgy0xCVY7EmequVyWlH6/B5GVB2xTMQuAz3f8pKm+XUr6C/twROYkgoXbV
 AOVyRWtnbISDVjtVFn9c
 =KcDx
 -----END PGP SIGNATURE-----

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio updates from Rusty Russell:
 "All trivial, thanks to the stuff which didn't quite make it time"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_console: Initialize guest_connected=true for rproc_serial
  virtio: use module_virtio_driver.
  virtio: Add module driver macro for virtio drivers.
  virtio_console: Use virtio device index to generate port name
  virtio: make pci_device_id const
  virtio: make config_ops const
  virtio-mmio: fix wrong comment about register offset
  virtio_console: Let unconnected rproc device receive data.
2013-02-26 14:49:12 -08:00
Rusty Russell b2a17029c2 virtio: use module_virtio_driver.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-02-13 17:00:37 +10:30
Stephen Hemminger 35cdc9eb65 virtio: make pci_device_id const
Use DEVICE_TABLE macro which also makes table const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-02-11 15:32:18 +10:30
Stephen Hemminger 9350393239 virtio: make config_ops const
It is just a table of function pointers, make it const for cleanliness and security
reasons.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-02-11 15:32:17 +10:30
Ryota Ozaki 0d34cc2d6d virtio-mmio: fix wrong comment about register offset
The register offset of InterruptACK is 0x064, not 0x060.
Fix it.

Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
CC: Jiri Kosina <trivial@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-02-04 10:37:01 +10:30
Kees Cook d72c5a8c8c drivers/virtio: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Rusty Russell <rusty@rustcorp.com.au>
CC: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-11 11:39:04 -08:00
Greg Kroah-Hartman 8590dbc79a Drivers: virtio: remove __dev* attributes.
CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, and __devexit
from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:01 -08:00
Linus Torvalds b7dfde956d Some nice cleanups, and even a patch my wife did as a "live" demo for
Latinoware 2012.
 
 There's a slightly non-trivial merge in virtio-net, as we cleaned up the
 virtio add_buf interface while DaveM accepted the mq virtio-net patches.
 
 You can see my solution in my pending-rebases branch, if that helps, but I
 know you love merging:
 
 https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe
 
 Cheers,
 Rusty.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7
 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB
 /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP
 noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj
 iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz
 hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O
 OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd
 NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq
 Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK
 xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B
 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm
 WJv9uZPs+QbIMNky2Lcb
 =myDR
 -----END PGP SIGNATURE-----

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio update from Rusty Russell:
 "Some nice cleanups, and even a patch my wife did as a "live" demo for
  Latinoware 2012.

  There's a slightly non-trivial merge in virtio-net, as we cleaned up
  the virtio add_buf interface while DaveM accepted the mq virtio-net
  patches."

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits)
  virtio_console: Add support for remoteproc serial
  virtio_console: Merge struct buffer_token into struct port_buffer
  virtio: add drv_to_virtio to make code clearly
  virtio: use dev_to_virtio wrapper in virtio
  virtio-mmio: Fix irq parsing in command line parameter
  virtio_console: Free buffers from out-queue upon close
  virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>(
  virtio_console: Use kmalloc instead of kzalloc
  virtio_console: Free buffer if splice fails
  virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0
  virtio: make virtqueue_add_buf() returning 0 on success, not capacity.
  virtio: console: don't rely on virtqueue_add_buf() returning capacity.
  virtio_net: don't rely on virtqueue_add_buf() returning capacity.
  virtio-net: remove unused skb_vnet_hdr->num_sg field
  virtio-net: correct capacity math on ring full
  virtio: move queue_index and num_free fields into core struct virtqueue.
  ...
2012-12-20 08:37:05 -08:00
Wanlong Gao 9a2bdcc85d virtio: add drv_to_virtio to make code clearly
Add drv_to_virtio wrapper to get virtio_driver from device_driver.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:43 +10:30
Wanlong Gao 9bffdca8c6 virtio: use dev_to_virtio wrapper in virtio
Use dev_to_virtio wrapper in virtio to make code clearly.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:42 +10:30
Pawel Moll 40f9938c4c virtio-mmio: Fix irq parsing in command line parameter
When the resource_size_t is 64-bit long, the sscanf() on
the virtio device command line paramter string may return
wrong value because its format was defined as "%u". Fixed
by using an intermediate local value of a known length.

Also added cleaned up the resource creation and added extra
comments to make the parameters parsing easier to follow.

Reported-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:41 +10:30
Joe Perches 800ba5eabf virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>(
dev_<level> calls take less code than dev_printk(KERN_<LEVEL>
and reducing object size is good.
Convert if (printk_ratelimit()) dev_printk to dev_<level>_ratelimited.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:40 +10:30
Rusty Russell 98e8c6bc66 virtio: make virtqueue_add_buf() returning 0 on success, not capacity.
Now noone relies on this behavior, we simplify virtqueue_add_buf() so it
return 0 or -errno.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-18 15:20:34 +10:30
Rusty Russell 06ca287dba virtio: move queue_index and num_free fields into core struct virtqueue.
They're generic concepts, so hoist them.  This also avoids accessor
functions (though kept around for merge with DaveM's net tree).

This goes even further than Jason Wang's 17bb6d4088 patch
("virtio-ring: move queue_index to vring_virtqueue") which moved the
queue_index from the specific transport.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:31 +10:30
Wei Yongjun 1ce6853aa0 virtio-pci: use module_pci_driver to simplify the code
Use the module_pci_driver() macro to make the code simpler
by eliminating module_init and module_exit calls.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:30 +10:30
Rafael Aquini e22504296d virtio_balloon: introduce migration primitives to balloon pages
Memory fragmentation introduced by ballooning might reduce significantly
the number of 2MB contiguous memory blocks that can be used within a guest,
thus imposing performance penalties associated with the reduced number of
transparent huge pages that could be used by the guest workload.

Besides making balloon pages movable at allocation time and introducing
the necessary primitives to perform balloon page migration/compaction,
this patch also introduces the following locking scheme, in order to
enhance the syncronization methods for accessing elements of struct
virtio_balloon, thus providing protection against concurrent access
introduced by parallel memory migration threads.

 - balloon_lock (mutex) : synchronizes the access demand to elements of
                          struct virtio_balloon and its queue operations;

[yongjun_wei@trendmicro.com.cn: fix missing unlock on error in fill_balloon()]
[akpm@linux-foundation.org: avoid having multiple return points in fill_balloon()]
[akpm@linux-foundation.org: fix printk warning]Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11 17:22:27 -08:00
Cornelia Huck 237242bddc virtio: Don't access index after unregister.
Virtio wants to release used indices after the corresponding
virtio device has been unregistered. However, virtio does not
hold an extra reference, giving up its last reference with
device_unregister(), making accessing dev->index afterwards
invalid.

I actually saw problems when testing my (not-yet-merged)
virtio-ccw code:

- device_add virtio-net,id=xxx
-> creates device virtio<n> with n>0

- device_del xxx
-> deletes virtio<n>, but calls ida_simple_remove with an
   index of 0

- device_add virtio-net,id=xxx
-> tries to add virtio0, which is still in use...

So let's save the index we want to release before calling
device_unregister().

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Cc: stable@kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-11-09 14:54:24 +10:30
Will Deacon b92b1b89a3 virtio: force vring descriptors to be allocated from lowmem
Virtio devices may attempt to add descriptors to a virtqueue from atomic
context using GFP_ATOMIC allocation. This is problematic because such
allocations can fall outside of the lowmem mapping, causing virt_to_phys
to report bogus physical addresses which are subsequently passed to
userspace via the buffers for the virtual device.

This patch masks out __GFP_HIGH and __GFP_HIGHMEM from the requested
flags when allocating descriptors for a virtqueue. If an atomic
allocation is requested and later fails, we will return -ENOSPC which
will be handled by the driver.

Cc: stable@kernel.org
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-22 18:19:49 +10:30
Brian Foley d78b519f6b virtio_mmio: Don't attempt to create empty virtqueues
If a virtio device reports a QueueNumMax of 0, vring_new_virtqueue()
doesn't check this, and thanks to an unsigned (i < num - 1) loop
guard, scribbles over memory when initialising the free list.

Avoid by not trying to create zero-descriptor queues, as there's no
way to do any I/O with one.

Signed-off-by: Brian Foley <brian.foley@arm.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:16 +09:30
Brian Foley 3850d29fc4 virtio_mmio: fix off by one error allocating queue
vm_setup_vq fails to allow VirtQueues needing only 2 pages of
storage, as it should. Found with a kernel using 64kB pages, but
can be provoked if a virtio device reports QueueNumMax where the
descriptor table and available ring fit in one page, and the used
ring on the second (<= 227 descriptors with 4kB pages and <= 3640
with 64kB pages.)

Signed-off-by: Brian Foley <brian.foley@arm.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:16 +09:30
Peter Senna Tschudin 74a74b376c drivers/virtio/virtio_pci.c: fix error return code
Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:16 +09:30
Michael S. Tsirkin 5543a6ac31 virtio: don't crash when device is buggy
Because of a sanity check in virtio_dev_remove, a buggy device can crash
kernel.  And in case of rproc it's userspace so it's not a good idea.
We are unloading a driver so how bad can it be?
Be less aggressive in handling this error: if it's a driver bug,
warning once should be enough.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:16 +09:30
Rusty Russell eccbb05a64 virtio: remove CONFIG_VIRTIO_RING
Everyone who selects VIRTIO is also made to select VIRTIO_RING; just make
them synonymous, since we removed the indirection layer some time ago.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Rusty Russell 387daf1716 virtio: add help to CONFIG_VIRTIO option.
Trying to enable a virtio driver (eg CONFIG_VIRTIO_BLK) is painful
because it depends on CONFIG_VIRTIO.  CONFIG_VIRTIO doesn't tell you
how to turn it on (it's selected from anything which provides a virtio
bus).

This patch at least adds some documentation, visible in menuconfig, as
a hint.

Reported-by: Kent Overstreet <koverstreet@google.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Michael S. Tsirkin 6457f126c8 virtio: support reserved vqs
virtio network device multiqueue support reserves
vq 3 for future use (useful both for future extensions and to make it
pretty - this way receive vqs have even and transmit - odd numbers).
Make it possible to skip initialization for
specific vq numbers by specifying NULL for name.
Document this usage as well as (existing) NULL callback.

Drivers using this not coded up yet, so I simply tested
with virtio-pci and verified that this patch does
not break existing drivers.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Jason Wang 75a0a52be3 virtio: introduce an API to set affinity for a virtqueue
Sometimes, virtio device need to configure irq affinity hint to maximize the
performance. Instead of just exposing the irq of a virtqueue, this patch
introduce an API to set the affinity for a virtqueue.

The api is best-effort, the affinity hint may not be set as expected due to
platform support, irq sharing or irq type. Currently, only pci method were
implemented and we set the affinity according to:

- if device uses INTX, we just ignore the request
- if device has per vq vector, we force the affinity hint
- if the virtqueues share MSI, make the affinity OR over all affinities
  requested

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Jason Wang 17bb6d4088 virtio-ring: move queue_index to vring_virtqueue
Instead of storing the queue index in transport-specific virtio structs,
this patch moves them to vring_virtqueue and introduces an helper to get
the value.  This lets drivers simplify their management and tracing of
virtqueues.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:15 +09:30
Rusty Russell 7a23eb28fa virtio_balloon: not EXPERIMENTAL any more.
It is not experimental in any vaguely-sane sense.

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:14 +09:30
Michael S. Tsirkin 04679f34c1 virtio-balloon: dependency fix
Devices should depend on virtio, not select it.  It's supposed to be
selected by the particular driver, e.g. VIRTIO_PCI.
Make balloon depend on VIRTIO and EXPERIMENTAL
(to match description).

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-09-28 15:05:14 +09:30
Nicholas Bellinger 59057fbc37 [SCSI] virtio-scsi: Add vdrv->scan for post VIRTIO_CONFIG_S_DRIVER_OK LUN scanning
This patch changes virtio-scsi to use a new virtio_driver->scan() callback
so that scsi_scan_host() can be properly invoked once virtio_dev_probe() has
set add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK) to signal active virtio-ring
operation, instead of from within virtscsi_probe().

This fixes a bug where SCSI LUN scanning for both virtio-scsi-raw and
virtio-scsi/tcm_vhost setups was happening before VIRTIO_CONFIG_S_DRIVER_OK
had been set, causing VIRTIO_SCSI_S_BAD_TARGET to occur.  This fixes a bug
with virtio-scsi/tcm_vhost where LUN scan was not detecting LUNs.

Tested with virtio-scsi-raw + virtio-scsi/tcm_vhost w/ IBLOCK on 3.5-rc2 code.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:59:03 +01:00
Michael S. Tsirkin 9c378abc5c virtio-balloon: fix add/get API use
Since ee7cd8981e 'virtio: expose added
descriptors immediately.', in virtio balloon virtqueue_get_buf might
now run concurrently with virtqueue_kick.  I audited both and this
seems safe in practice but this is not guaranteed by the API.
Additionally, a spurious interrupt might in theory make
virtqueue_get_buf run in parallel with virtqueue_add_buf, which is
racy.

While we might try to protect against spurious callbacks it's
easier to fix the driver: balloon seems to be the only one
(mis)using the API like this, so let's just fix balloon.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed unused var)
2012-07-09 09:07:22 +09:30
Pawel Moll 81a054ce0b virtio-mmio: Devices parameter parsing
This patch adds an option to instantiate guest virtio-mmio devices
basing on a kernel command line (or module) parameter, for example:

	virtio_mmio.devices=0x100@0x100b0000:48

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-05-22 12:16:15 +09:30
Asias He 90e03207f4 virtio: Use ida to allocate virtio index
Current index allocation in virtio is based on a monotonically
increasing variable "index". This means we'll run out of numbers
after a while. E.g. someone crazy doing this in host side.

while(1) {
	hot-plug a virtio device
	hot-unplug the virito devcie
}

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-05-22 12:16:12 +09:30
Amit Shah c877bab507 virtio: balloon: separate out common code between remove and freeze functions
The remove and freeze functions have a lot of shared code; put it into a
common function that gets called by both.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-05-22 12:16:11 +09:30
Amit Shah c45b4166d9 virtio: balloon: drop restore_common()
restore_common() was used when there were different thaw and freeze PM
callbacks implemented.  We removed thaw in commit
f38f8387cb.

restore_common() can be removed and virtballoon_restore() can itself do
the restore ops.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-05-22 12:16:11 +09:30
Amit Shah b8ae0eb320 virtio: balloon: let host know of updated balloon size before module removal
When the balloon module is removed, we deflate the balloon, reclaiming
all the pages that were given to the host.  However, we don't update the
config values for the new balloon size, resulting in the host showing
outdated balloon values.

The size update is done after each leak and fill operation, only the
module removal case was left out.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-17 12:14:34 +03:00
Michael S. Tsirkin 3ccc9372ed virtio_balloon: fix handling of PAGE_SIZE != 4k
As reported by David Gibson, current code handles PAGE_SIZE != 4k
completely wrong which can lead to guest memory corruption errors:

- page_to_balloon_pfn is wrong: e.g. on system with 64K page size
 it gives the same pfn value for 16 different pages.

- we also need to convert back to linux pfns when we free.

- for each linux page we need to tell host about multiple balloon
  pages, but code only adds one pfn to the array.

This patch fixes all that, tested with a 64k ppc64 kernel.

Reported-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-04-15 11:51:06 +03:00
David Gibson 1a87228f5f virtio_balloon: Fix endian bug
Although virtio config space fields are usually in guest-native endian,
the spec for the virtio balloon device explicitly states that both fields
in its config space are little-endian.

However, the current virtio_balloon driver does not have a suitable endian
swap for the 'num_pages' field, although it does have one for the 'actual'
field.  This patch corrects the bug, adding sparse annotation while we're
at it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-04-15 11:51:05 +03:00
Amit Shah f878d0be22 virtio-pci: switch to PM ops macro to initialise PM functions
Use the SET_SYSTEM_SLEEP_PM_OPS macro to initialise the suspend/resume
functions in the new PM API.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
2012-03-31 08:09:51 +05:30
Amit Shah 04c2322bee virtio-pci: S3 support
There's no difference in supporting S3 and S4 for virtio devices: the
vqs have to be re-created as the device has to be assumed to be reset at
restore-time.  Since S4 already handles this situation, we can directly
use the same code and callbacks for S3 support.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
2012-03-31 08:09:51 +05:30
Amit Shah 0517fdd156 virtio-pci: drop restore_common()
restore_common() was shared between restore and thaw callbacks.  With
thaw gone, we don't need restore_common() anymore.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
2012-03-31 08:09:51 +05:30