* Re: [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: Andrew Cooper @ 2015-12-20 17:07 UTC (permalink / raw)
To: Michael S. Tsirkin, Peter Zijlstra
Cc: qemu-devel, Alexander Duyck, linux-kernel, David Vrabel,
xen-devel, Boris Ostrovsky, virtualization
In-Reply-To: <20151220105146-mutt-send-email-mst@redhat.com>
On 20/12/15 09:25, Michael S. Tsirkin wrote:
> On Thu, Dec 17, 2015 at 03:39:10PM +0100, Peter Zijlstra wrote:
>> On Thu, Dec 17, 2015 at 04:33:44PM +0200, Michael S. Tsirkin wrote:
>>> On Thu, Dec 17, 2015 at 02:57:26PM +0100, Peter Zijlstra wrote:
>>>> You could of course go fix that instead of mutilating things into
>>>> sort-of functional state.
>>> Yes, we'd just need to touch all architectures, all for
>>> the sake of UP which almost no one uses.
>>> Basically, we need APIs that explicitly are
>>> for talking to another kernel on a different CPU on
>>> the same SMP system, and implemented identically
>>> between CONFIG_SMP and !CONFIG_SMP on all architectures.
>>>
>>> Do you think this is something of general usefulness,
>>> outside virtio?
>> I'm not aware of any other case, but if there are more parts of virt
>> that need this then I see no problem adding it.
> When I wrote this, I assumed there are no other users, and I'm still not
> sure there are other users at the moment. Do you see a problem then?
>
>> That is, virt in general is the only use-case that I can think of,
>> because this really is an artifact of interfacing with an SMP host while
>> running an UP kernel.
> Or another guest kernel on an SMP host.
>
>> But I'm really not familiar with virt, so I do not know if there's more
>> sites outside of virtio that could use this.
>> Touching all archs is a tad tedious, but its fairly straight forward.
> So I looked and I was only able to find other another possible user in Xen.
>
> Cc Xen folks.
>
> I noticed that drivers/xen/xenbus/xenbus_comms.c uses
> full memory barriers to communicate with the other side.
> For example:
>
> /* Must write data /after/ reading the consumer index. * */
> mb();
>
> memcpy(dst, data, avail);
> data += avail;
> len -= avail;
>
> /* Other side must not see new producer until data is * there. */
> wmb();
> intf->req_prod += avail;
>
> /* Implies mb(): other side will see the updated producer. */
> notify_remote_via_evtchn(xen_store_evtchn);
>
> To me, it looks like for guests compiled with CONFIG_SMP, smp_wmb and smp_mb
> would be sufficient, so mb() and wmb() here are only needed if
> a non-SMP guest runs on an SMP host.
>
> Is my analysis correct?
Correct. The reason full barriers are used is so non-SMP guests still
function correctly. It is certainly inefficient.
>
> So what I'm suggesting is something like the below patch,
> except instead of using virtio directly, a new set of barriers
> that behaves identically for SMP and non-SMP guests will be introduced.
>
> And of course the weak barriers flag is not needed for Xen -
> that's a virtio only thing.
>
> For example:
>
> smp_pv_wmb()
> smp_pv_rmb()
> smp_pv_mb()
>
> I'd like to get confirmation from Xen folks before posting
> this patchset.
>
> Comments/suggestions?
Very much +1 for fixing this.
Those names would be fine, but they do add yet another set of options in
an already-complicated area.
An alternative might be to have the regular smp_{w,r,}mb() not revert
back to nops if CONFIG_PARAVIRT, or perhaps if pvops have detected a
non-native environment. (I don't know how feasible this suggestion is,
however.)
~Andrew
^ permalink raw reply
* Re: [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: Peter Zijlstra @ 2015-12-20 19:59 UTC (permalink / raw)
To: Andrew Cooper
Cc: Michael S. Tsirkin, linux-kernel, Alexander Duyck, qemu-devel,
David Vrabel, xen-devel, Boris Ostrovsky, virtualization
In-Reply-To: <5676E047.3010808@citrix.com>
On Sun, Dec 20, 2015 at 05:07:19PM +0000, Andrew Cooper wrote:
>
> Very much +1 for fixing this.
>
> Those names would be fine, but they do add yet another set of options in
> an already-complicated area.
>
> An alternative might be to have the regular smp_{w,r,}mb() not revert
> back to nops if CONFIG_PARAVIRT, or perhaps if pvops have detected a
> non-native environment. (I don't know how feasible this suggestion is,
> however.)
So a regular SMP kernel emits the LOCK prefix and will patch it out with
a DS prefix (iirc) when it finds but a single CPU. So for those you
could easily do this.
However an UP kernel will not emit the LOCK and do no patching.
So if you're willing to make CONFIG_PARAVIRT depend on CONFIG_SMP or
similar, this is doable.
I don't see people going to allow emitting the LOCK prefix (and growing
the kernel text size) for UP kernels.
^ permalink raw reply
* Re: [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: Michael S. Tsirkin @ 2015-12-21 7:10 UTC (permalink / raw)
To: Peter Zijlstra
Cc: linux-arch, Arnd Bergmann, Andrew Cooper, qemu-devel,
Alexander Duyck, linux-kernel, David Vrabel, xen-devel,
Boris Ostrovsky, virtualization
In-Reply-To: <20151220195944.GT6344@twins.programming.kicks-ass.net>
On Sun, Dec 20, 2015 at 08:59:44PM +0100, Peter Zijlstra wrote:
> On Sun, Dec 20, 2015 at 05:07:19PM +0000, Andrew Cooper wrote:
> >
> > Very much +1 for fixing this.
> >
> > Those names would be fine, but they do add yet another set of options in
> > an already-complicated area.
> >
> > An alternative might be to have the regular smp_{w,r,}mb() not revert
> > back to nops if CONFIG_PARAVIRT, or perhaps if pvops have detected a
> > non-native environment. (I don't know how feasible this suggestion is,
> > however.)
>
> So a regular SMP kernel emits the LOCK prefix and will patch it out with
> a DS prefix (iirc) when it finds but a single CPU. So for those you
> could easily do this.
>
> However an UP kernel will not emit the LOCK and do no patching.
>
> So if you're willing to make CONFIG_PARAVIRT depend on CONFIG_SMP or
> similar, this is doable.
One of the uses for virtio is to allow testing an existing kernel on
kvm just by loading a module, and this will break this usecase.
> I don't see people going to allow emitting the LOCK prefix (and growing
> the kernel text size) for UP kernels.
Thinking about this more, maybe __smp_*mb is a better set of names.
The nice thing about it is that we can then have generic code
that does basically
#ifdef CONFIG_SMP
#define smp_mb() __smp_mb()
#else
#define smp_mb() barrier()
#endif
and reuse this on all architectures.
So instead of a maintainance burden, we are actually
removing code duplication.
--
MST
^ permalink raw reply
* [PATCH RFC] smp_store_mb should use smp_mb
From: Michael S. Tsirkin @ 2015-12-21 7:22 UTC (permalink / raw)
To: Peter Zijlstra
Cc: linux-arch, Arnd Bergmann, Andrew Cooper, qemu-devel,
Alexander Duyck, linux-kernel, David Vrabel, xen-devel,
Boris Ostrovsky, virtualization
In-Reply-To: <20151221085947-mutt-send-email-mst@redhat.com>
On some architectures smp_store_mb() calls mb() which is stronger
than implied by both the name and the documentation.
smp_store_mb is only used by core kernel code at the moment, so
we know no one mis-uses it for an MMIO barrier.
Make it call smp_mb consistently before some arch-specific
code uses it as such by mistake.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
Note: I'm guessing an ack from arch maintainers will be needed, but
I'm working on a bigger cleanup moving a bunch of duplicated code
into asm-generic/barrier.h which depends on this, so not Cc'ing
widely yet.
Please Ack if appropriate but do not merge yet.
diff --git a/arch/ia64/include/asm/barrier.h b/arch/ia64/include/asm/barrier.h
index df896a1..425552b 100644
--- a/arch/ia64/include/asm/barrier.h
+++ b/arch/ia64/include/asm/barrier.h
@@ -77,7 +77,7 @@ do { \
___p1; \
})
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
/*
* The group barrier in front of the rsm & ssm are necessary to ensure
diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
index 0eca6ef..4f0169e 100644
--- a/arch/powerpc/include/asm/barrier.h
+++ b/arch/powerpc/include/asm/barrier.h
@@ -34,7 +34,7 @@
#define rmb() __asm__ __volatile__ ("sync" : : : "memory")
#define wmb() __asm__ __volatile__ ("sync" : : : "memory")
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
#ifdef __SUBARCH_HAS_LWSYNC
# define SMPWMB LWSYNC
diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
index d68e11e..6c1d8b5 100644
--- a/arch/s390/include/asm/barrier.h
+++ b/arch/s390/include/asm/barrier.h
@@ -36,7 +36,7 @@
#define smp_mb__before_atomic() smp_mb()
#define smp_mb__after_atomic() smp_mb()
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
#define smp_store_release(p, v) \
do { \
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index b42afad..0f45f93 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -93,7 +93,7 @@
#endif /* CONFIG_SMP */
#ifndef smp_store_mb
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
#endif
#ifndef smp_mb__before_atomic
^ permalink raw reply related
* [PULL] vhost: cleanups and fixes
From: Michael S. Tsirkin @ 2015-12-21 7:58 UTC (permalink / raw)
To: Linus Torvalds; +Cc: kvm, mst, netdev, linux-kernel, virtualization
The following changes since commit 9f9499ae8e6415cefc4fe0a96ad0e27864353c89:
Linux 4.4-rc5 (2015-12-13 17:42:58 -0800)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/for_linus
for you to fetch changes up to 74a599f09bec7419b2490039f0fb33bc8581ef7c:
virtio/s390: handle error values in irb (2015-12-17 10:37:33 +0200)
----------------------------------------------------------------
virtio: fixes on top of 4.4-rc5
This includes a single fix for virtio ccw error handling.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
----------------------------------------------------------------
Cornelia Huck (1):
virtio/s390: handle error values in irb
drivers/s390/virtio/virtio_ccw.c | 62 ++++++++++++++++++++++++----------------
1 file changed, 37 insertions(+), 25 deletions(-)
^ permalink raw reply
* Re: [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: David Vrabel @ 2015-12-21 10:47 UTC (permalink / raw)
To: Michael S. Tsirkin, Peter Zijlstra
Cc: Ian Campbell, qemu-devel, Alexander Duyck, linux-kernel,
David Vrabel, xen-devel, Boris Ostrovsky, virtualization
In-Reply-To: <20151220105146-mutt-send-email-mst@redhat.com>
On 20/12/15 09:25, Michael S. Tsirkin wrote:
>
> I noticed that drivers/xen/xenbus/xenbus_comms.c uses
> full memory barriers to communicate with the other side.
> For example:
>
> /* Must write data /after/ reading the consumer index. * */
> mb();
>
> memcpy(dst, data, avail);
> data += avail;
> len -= avail;
>
> /* Other side must not see new producer until data is * there. */
> wmb();
> intf->req_prod += avail;
>
> /* Implies mb(): other side will see the updated producer. */
> notify_remote_via_evtchn(xen_store_evtchn);
>
> To me, it looks like for guests compiled with CONFIG_SMP, smp_wmb and smp_mb
> would be sufficient, so mb() and wmb() here are only needed if
> a non-SMP guest runs on an SMP host.
>
> Is my analysis correct?
For x86, yes.
For arm/arm64 I think so, but would prefer one of the Xen arm
maintainers to confirm. In particular, whether inner-shareable barriers
are sufficient for memory shared with the hypervisor.
> So what I'm suggesting is something like the below patch,
> except instead of using virtio directly, a new set of barriers
> that behaves identically for SMP and non-SMP guests will be introduced.
>
> And of course the weak barriers flag is not needed for Xen -
> that's a virtio only thing.
>
> For example:
>
> smp_pv_wmb()
> smp_pv_rmb()
> smp_pv_mb()
The smp_ prefix doesn't make a lot of sense to me here since these
barriers are going to be the same whether the kernel is SMP or not.
David
^ permalink raw reply
* Re: [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: Michael S. Tsirkin @ 2015-12-21 11:52 UTC (permalink / raw)
To: David Vrabel
Cc: Ian Campbell, Peter Zijlstra, qemu-devel, Alexander Duyck,
linux-kernel, xen-devel, Boris Ostrovsky, virtualization
In-Reply-To: <5677D8D5.7080700@citrix.com>
On Mon, Dec 21, 2015 at 10:47:49AM +0000, David Vrabel wrote:
> On 20/12/15 09:25, Michael S. Tsirkin wrote:
> >
> > I noticed that drivers/xen/xenbus/xenbus_comms.c uses
> > full memory barriers to communicate with the other side.
> > For example:
> >
> > /* Must write data /after/ reading the consumer index. * */
> > mb();
> >
> > memcpy(dst, data, avail);
> > data += avail;
> > len -= avail;
> >
> > /* Other side must not see new producer until data is * there. */
> > wmb();
> > intf->req_prod += avail;
> >
> > /* Implies mb(): other side will see the updated producer. */
> > notify_remote_via_evtchn(xen_store_evtchn);
> >
> > To me, it looks like for guests compiled with CONFIG_SMP, smp_wmb and smp_mb
> > would be sufficient, so mb() and wmb() here are only needed if
> > a non-SMP guest runs on an SMP host.
> >
> > Is my analysis correct?
>
> For x86, yes.
>
> For arm/arm64 I think so, but would prefer one of the Xen arm
> maintainers to confirm. In particular, whether inner-shareable barriers
> are sufficient for memory shared with the hypervisor.
>
> > So what I'm suggesting is something like the below patch,
> > except instead of using virtio directly, a new set of barriers
> > that behaves identically for SMP and non-SMP guests will be introduced.
> >
> > And of course the weak barriers flag is not needed for Xen -
> > that's a virtio only thing.
> >
> > For example:
> >
> > smp_pv_wmb()
> > smp_pv_rmb()
> > smp_pv_mb()
>
> The smp_ prefix doesn't make a lot of sense to me here since these
> barriers are going to be the same whether the kernel is SMP or not.
>
> David
Guest kernel - yes. But it's only needed because you
are running on an SMP host.
--
MST
^ permalink raw reply
* Re: [Qemu-devel] [Xen-devel] new barrier type for paravirt (was Re: [PATCH] virtio_ring: use smp_store_mb)
From: Stefano Stabellini @ 2015-12-21 14:50 UTC (permalink / raw)
To: David Vrabel
Cc: Ian Campbell, Michael S. Tsirkin, Peter Zijlstra, qemu-devel,
Alexander Duyck, linux-kernel, xen-devel, Boris Ostrovsky,
virtualization, linux-arm-kernel
In-Reply-To: <5677D8D5.7080700@citrix.com>
On Mon, 21 Dec 2015, David Vrabel wrote:
> On 20/12/15 09:25, Michael S. Tsirkin wrote:
> >
> > I noticed that drivers/xen/xenbus/xenbus_comms.c uses
> > full memory barriers to communicate with the other side.
> > For example:
> >
> > /* Must write data /after/ reading the consumer index. * */
> > mb();
> >
> > memcpy(dst, data, avail);
> > data += avail;
> > len -= avail;
> >
> > /* Other side must not see new producer until data is * there. */
> > wmb();
> > intf->req_prod += avail;
> >
> > /* Implies mb(): other side will see the updated producer. */
> > notify_remote_via_evtchn(xen_store_evtchn);
> >
> > To me, it looks like for guests compiled with CONFIG_SMP, smp_wmb and smp_mb
> > would be sufficient, so mb() and wmb() here are only needed if
> > a non-SMP guest runs on an SMP host.
> >
> > Is my analysis correct?
>
> For x86, yes.
>
> For arm/arm64 I think so, but would prefer one of the Xen arm
> maintainers to confirm. In particular, whether inner-shareable barriers
> are sufficient for memory shared with the hypervisor.
inner-shareable barriers are certainly OK. In this case there would be
also a switch from dsb to dmb barriers, which I also think should be OK.
What about all the mb() and wmb() in RING_PUSH_REQUESTS and
RING_PUSH_RESPONSES in include/xen/interface/io/ring.h ?
> > So what I'm suggesting is something like the below patch,
> > except instead of using virtio directly, a new set of barriers
> > that behaves identically for SMP and non-SMP guests will be introduced.
> >
> > And of course the weak barriers flag is not needed for Xen -
> > that's a virtio only thing.
> >
> > For example:
> >
> > smp_pv_wmb()
> > smp_pv_rmb()
> > smp_pv_mb()
>
> The smp_ prefix doesn't make a lot of sense to me here since these
> barriers are going to be the same whether the kernel is SMP or not.
^ permalink raw reply
* [RFC v4 0/5] Add virtio transport for AF_VSOCK
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Christoffer Dall, matt.ma
This series is based on v4.4-rc2 and the "virtio: make find_vqs()
checkpatch.pl-friendly" patch I recently submitted.
v4:
* Addressed code review comments from Alex Bennee
* MAINTAINERS file entries for new files
* Trace events instead of pr_debug()
* RST packet is sent when there is no listen socket
* Allow guest->host connections again (began discussing netfilter support with
Matt Benjamin instead of hard-coding security policy in virtio-vsock code)
* Many checkpatch.pl cleanups (will be 100% clean in v5)
v3:
* Remove unnecessary 3-way handshake, just do REQUEST/RESPONSE instead
of REQUEST/RESPONSE/ACK
* Remove SOCK_DGRAM support and focus on SOCK_STREAM first
(also drop v2 Patch 1, it's only needed for SOCK_DGRAM)
* Only allow host->guest connections (same security model as latest
VMware)
* Don't put vhost vsock driver into staging
* Add missing Kconfig dependencies (Arnd Bergmann <arnd@arndb.de>)
* Remove unneeded variable used to store return value
(Fengguang Wu <fengguang.wu@intel.com> and Julia Lawall
<julia.lawall@lip6.fr>)
v2:
* Rebased onto Linux v4.4-rc2
* vhost: Refuse to assign reserved CIDs
* vhost: Refuse guest CID if already in use
* vhost: Only accept correctly addressed packets (no spoofing!)
* vhost: Support flexible rx/tx descriptor layout
* vhost: Add missing total_tx_buf decrement
* virtio_transport: Fix total_tx_buf accounting
* virtio_transport: Add virtio_transport global mutex to prevent races
* common: Notify other side of SOCK_STREAM disconnect (fixes shutdown
semantics)
* common: Avoid recursive mutex_lock(tx_lock) for write_space (fixes deadlock)
* common: Define VIRTIO_VSOCK_TYPE_STREAM/DGRAM hardware interface constants
* common: Define VIRTIO_VSOCK_SHUTDOWN_RCV/SEND hardware interface constants
* common: Fix peer_buf_alloc inheritance on child socket
This patch series adds a virtio transport for AF_VSOCK (net/vmw_vsock/).
AF_VSOCK is designed for communication between virtual machines and
hypervisors. It is currently only implemented for VMware's VMCI transport.
This series implements the proposed virtio-vsock device specification from
here:
http://permalink.gmane.org/gmane.comp.emulators.virtio.devel/980
Most of the work was done by Asias He and Gerd Hoffmann a while back. I have
picked up the series again.
The QEMU userspace changes are here:
https://github.com/stefanha/qemu/commits/vsock
Why virtio-vsock?
-----------------
Guest<->host communication is currently done over the virtio-serial device.
This makes it hard to port sockets API-based applications and is limited to
static ports.
virtio-vsock uses the sockets API so that applications can rely on familiar
SOCK_STREAM semantics. Applications on the host can easily connect to guest
agents because the sockets API allows multiple connections to a listen socket
(unlike virtio-serial). This simplifies the guest<->host communication and
eliminates the need for extra processes on the host to arbitrate virtio-serial
ports.
Overview
--------
This series adds 3 pieces:
1. virtio_transport_common.ko - core virtio vsock code that uses vsock.ko
2. virtio_transport.ko - guest driver
3. drivers/vhost/vsock.ko - host driver
Howto
-----
The following kernel options are needed:
CONFIG_VSOCKETS=y
CONFIG_VIRTIO_VSOCKETS=y
CONFIG_VIRTIO_VSOCKETS_COMMON=y
CONFIG_VHOST_VSOCK=m
Launch QEMU as follows:
# qemu ... -device vhost-vsock-pci,id=vhost-vsock-pci0,guest-cid=3
Guest and host can communicate via AF_VSOCK sockets. The host's CID (address)
is 2 and the guest must be assigned a CID (3 in the example above).
Status
------
This patch series implements the latest draft specification. Please review.
Asias He (4):
VSOCK: Introduce virtio_vsock_common.ko
VSOCK: Introduce virtio_transport.ko
VSOCK: Introduce vhost_vsock.ko
VSOCK: Add Makefile and Kconfig
Stefan Hajnoczi (1):
VSOCK: transport-specific vsock_transport functions
MAINTAINERS | 13 +
drivers/vhost/Kconfig | 15 +
drivers/vhost/Makefile | 4 +
drivers/vhost/vsock.c | 607 +++++++++++++++
drivers/vhost/vsock.h | 4 +
include/linux/virtio_vsock.h | 167 +++++
include/net/af_vsock.h | 3 +
.../trace/events/vsock_virtio_transport_common.h | 144 ++++
include/uapi/linux/virtio_ids.h | 1 +
include/uapi/linux/virtio_vsock.h | 87 +++
net/vmw_vsock/Kconfig | 19 +
net/vmw_vsock/Makefile | 2 +
net/vmw_vsock/af_vsock.c | 9 +
net/vmw_vsock/virtio_transport.c | 481 ++++++++++++
net/vmw_vsock/virtio_transport_common.c | 834 +++++++++++++++++++++
15 files changed, 2390 insertions(+)
create mode 100644 drivers/vhost/vsock.c
create mode 100644 drivers/vhost/vsock.h
create mode 100644 include/linux/virtio_vsock.h
create mode 100644 include/trace/events/vsock_virtio_transport_common.h
create mode 100644 include/uapi/linux/virtio_vsock.h
create mode 100644 net/vmw_vsock/virtio_transport.c
create mode 100644 net/vmw_vsock/virtio_transport_common.c
--
2.5.0
^ permalink raw reply
* [RFC v4 1/5] VSOCK: transport-specific vsock_transport functions
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Christoffer Dall, matt.ma
In-Reply-To: <1450775258-18287-1-git-send-email-stefanha@redhat.com>
struct vsock_transport contains function pointers called by AF_VSOCK
core code. The transport may want its own transport-specific function
pointers and they can be added after struct vsock_transport.
Allow the transport to fetch vsock_transport. It can downcast it to
access transport-specific function pointers.
The virtio transport will use this.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
include/net/af_vsock.h | 3 +++
net/vmw_vsock/af_vsock.c | 9 +++++++++
2 files changed, 12 insertions(+)
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index e9eb2d6..23f5525 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -165,6 +165,9 @@ static inline int vsock_core_init(const struct vsock_transport *t)
}
void vsock_core_exit(void);
+/* The transport may downcast this to access transport-specific functions */
+const struct vsock_transport *vsock_core_get_transport(void);
+
/**** UTILS ****/
void vsock_release_pending(struct sock *pending);
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 7fd1220..9783a38 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1994,6 +1994,15 @@ void vsock_core_exit(void)
}
EXPORT_SYMBOL_GPL(vsock_core_exit);
+const struct vsock_transport *vsock_core_get_transport(void)
+{
+ /* vsock_register_mutex not taken since only the transport uses this
+ * function and only while registered.
+ */
+ return transport;
+}
+EXPORT_SYMBOL_GPL(vsock_core_get_transport);
+
MODULE_AUTHOR("VMware, Inc.");
MODULE_DESCRIPTION("VMware Virtual Socket Family");
MODULE_VERSION("1.0.1.0-k");
--
2.5.0
^ permalink raw reply related
* [RFC v4 2/5] VSOCK: Introduce virtio_vsock_common.ko
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Asias He, Christoffer Dall, matt.ma
In-Reply-To: <1450775258-18287-1-git-send-email-stefanha@redhat.com>
From: Asias He <asias@redhat.com>
This module contains the common code and header files for the following
virtio_transporto and vhost_vsock kernel modules.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
v4:
* Add MAINTAINERS file entry
* checkpatch.pl cleanups
* linux_vsock.h: drop wrong copy-pasted license header
* Move tx sock refcounting to virtio_transport_alloc/free_pkt() to fix
leaks in error paths
* Add send_pkt_no_sock() to send RST packets with no listen socket
* Rename per-socket state from virtio_transport to virtio_vsock_sock
* Move send_pkt_ops to new virtio_transport struct
* Drop dumppkt function, packet capture will be added in the future
* Drop empty virtio_transport_dec_tx_pkt()
* Allow guest->host connections again
* Use trace events instead of pr_debug()
v3:
* Remove unnecessary 3-way handshake, just do REQUEST/RESPONSE instead
of REQUEST/RESPONSE/ACK
* Remove SOCK_DGRAM support and focus on SOCK_STREAM first
* Only allow host->guest connections (same security model as latest
VMware)
v2:
* Fix peer_buf_alloc inheritance on child socket
* Notify other side of SOCK_STREAM disconnect (fixes shutdown
semantics)
* Avoid recursive mutex_lock(tx_lock) for write_space (fixes deadlock)
* Define VIRTIO_VSOCK_TYPE_STREAM/DGRAM hardware interface constants
* Define VIRTIO_VSOCK_SHUTDOWN_RCV/SEND hardware interface constants
---
MAINTAINERS | 10 +
include/linux/virtio_vsock.h | 167 +++++
.../trace/events/vsock_virtio_transport_common.h | 144 ++++
include/uapi/linux/virtio_ids.h | 1 +
include/uapi/linux/virtio_vsock.h | 87 +++
net/vmw_vsock/virtio_transport_common.c | 834 +++++++++++++++++++++
6 files changed, 1243 insertions(+)
create mode 100644 include/linux/virtio_vsock.h
create mode 100644 include/trace/events/vsock_virtio_transport_common.h
create mode 100644 include/uapi/linux/virtio_vsock.h
create mode 100644 net/vmw_vsock/virtio_transport_common.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 050d0e7..d42db78 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11360,6 +11360,16 @@ S: Maintained
F: drivers/media/v4l2-core/videobuf2-*
F: include/media/videobuf2-*
+VIRTIO AND VHOST VSOCK DRIVER
+M: Stefan Hajnoczi <stefanha@redhat.com>
+L: kvm@vger.kernel.org
+L: virtualization@lists.linux-foundation.org
+L: netdev@vger.kernel.org
+S: Maintained
+F: include/linux/virtio_vsock.h
+F: include/uapi/linux/virtio_vsock.h
+F: net/vmw_vsock/virtio_transport_common.c
+
VIRTUAL SERIO DEVICE DRIVER
M: Stephen Chandler Paul <thatslyude@gmail.com>
S: Maintained
diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
new file mode 100644
index 0000000..4acf1ad
--- /dev/null
+++ b/include/linux/virtio_vsock.h
@@ -0,0 +1,167 @@
+#ifndef _LINUX_VIRTIO_VSOCK_H
+#define _LINUX_VIRTIO_VSOCK_H
+
+#include <uapi/linux/virtio_vsock.h>
+#include <linux/socket.h>
+#include <net/sock.h>
+#include <net/af_vsock.h>
+
+#define VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE 128
+#define VIRTIO_VSOCK_DEFAULT_BUF_SIZE (1024 * 256)
+#define VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE (1024 * 256)
+#define VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE (1024 * 4)
+#define VIRTIO_VSOCK_MAX_BUF_SIZE 0xFFFFFFFFUL
+#define VIRTIO_VSOCK_MAX_PKT_BUF_SIZE (1024 * 64)
+#define VIRTIO_VSOCK_MAX_TX_BUF_SIZE (1024 * 1024 * 16)
+#define VIRTIO_VSOCK_MAX_DGRAM_SIZE (1024 * 64)
+
+enum {
+ VSOCK_VQ_CTRL = 0,
+ VSOCK_VQ_RX = 1, /* for host to guest data */
+ VSOCK_VQ_TX = 2, /* for guest to host data */
+ VSOCK_VQ_MAX = 3,
+};
+
+/* Per-socket state (accessed via vsk->trans) */
+struct virtio_vsock_sock {
+ struct vsock_sock *vsk;
+
+ /* Protected by lock_sock(sk_vsock(trans->vsk)) */
+ u32 buf_size;
+ u32 buf_size_min;
+ u32 buf_size_max;
+
+ struct mutex tx_lock;
+ struct mutex rx_lock;
+
+ /* Protected by tx_lock */
+ u32 tx_cnt;
+ u32 buf_alloc;
+ u32 peer_fwd_cnt;
+ u32 peer_buf_alloc;
+
+ /* Protected by rx_lock */
+ u32 fwd_cnt;
+ u32 rx_bytes;
+ struct list_head rx_queue;
+};
+
+struct virtio_vsock_pkt {
+ struct virtio_vsock_hdr hdr;
+ struct work_struct work;
+ struct list_head list;
+ void *buf;
+ u32 len;
+ u32 off;
+};
+
+struct virtio_vsock_pkt_info {
+ u32 remote_cid, remote_port;
+ struct msghdr *msg;
+ u32 pkt_len;
+ u16 type;
+ u16 op;
+ u32 flags;
+};
+
+struct virtio_transport {
+ /* This must be the first field */
+ struct vsock_transport transport;
+
+ /* Send packet for a specific socket */
+ int (*send_pkt)(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt_info *info);
+
+ /* Send packet without a socket (e.g. RST). Prefer send_pkt() over
+ * send_pkt_no_sock() when a socket exists.
+ */
+ int (*send_pkt_no_sock)(struct virtio_vsock_pkt *pkt);
+};
+
+struct virtio_vsock_pkt *
+virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
+ size_t len,
+ u32 src_cid,
+ u32 src_port,
+ u32 dst_cid,
+ u32 dst_port);
+ssize_t
+virtio_transport_stream_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len,
+ int type);
+int
+virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len, int flags);
+
+s64 virtio_transport_stream_has_data(struct vsock_sock *vsk);
+s64 virtio_transport_stream_has_space(struct vsock_sock *vsk);
+
+int virtio_transport_do_socket_init(struct vsock_sock *vsk,
+ struct vsock_sock *psk);
+u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk);
+u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk);
+u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk);
+void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val);
+void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val);
+void virtio_transport_set_max_buffer_size(struct vsock_sock *vs, u64 val);
+int
+virtio_transport_notify_poll_in(struct vsock_sock *vsk,
+ size_t target,
+ bool *data_ready_now);
+int
+virtio_transport_notify_poll_out(struct vsock_sock *vsk,
+ size_t target,
+ bool *space_available_now);
+
+int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data);
+int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data);
+int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data);
+int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
+ size_t target, ssize_t copied, bool data_read,
+ struct vsock_transport_recv_notify_data *data);
+int virtio_transport_notify_send_init(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data);
+int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data);
+int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data);
+int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
+ ssize_t written, struct vsock_transport_send_notify_data *data);
+
+u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
+bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
+bool virtio_transport_stream_allow(u32 cid, u32 port);
+int virtio_transport_dgram_bind(struct vsock_sock *vsk,
+ struct sockaddr_vm *addr);
+bool virtio_transport_dgram_allow(u32 cid, u32 port);
+
+int virtio_transport_connect(struct vsock_sock *vsk);
+
+int virtio_transport_shutdown(struct vsock_sock *vsk, int mode);
+
+void virtio_transport_release(struct vsock_sock *vsk);
+
+ssize_t
+virtio_transport_stream_enqueue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len);
+int
+virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
+ struct sockaddr_vm *remote_addr,
+ struct msghdr *msg,
+ size_t len);
+
+void virtio_transport_destruct(struct vsock_sock *vsk);
+
+void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt);
+void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt);
+void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt);
+u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 wanted);
+void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit);
+
+#endif /* _LINUX_VIRTIO_VSOCK_H */
diff --git a/include/trace/events/vsock_virtio_transport_common.h b/include/trace/events/vsock_virtio_transport_common.h
new file mode 100644
index 0000000..b7f1d62
--- /dev/null
+++ b/include/trace/events/vsock_virtio_transport_common.h
@@ -0,0 +1,144 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM vsock
+
+#if !defined(_TRACE_VSOCK_VIRTIO_TRANSPORT_COMMON_H) || \
+ defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_VSOCK_VIRTIO_TRANSPORT_COMMON_H
+
+#include <linux/tracepoint.h>
+
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_STREAM);
+
+#define show_type(val) \
+ __print_symbolic(val, { VIRTIO_VSOCK_TYPE_STREAM, "STREAM" })
+
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_INVALID);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_REQUEST);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_RESPONSE);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_RST);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_SHUTDOWN);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_RW);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_CREDIT_UPDATE);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_CREDIT_REQUEST);
+
+#define show_op(val) \
+ __print_symbolic(val, \
+ { VIRTIO_VSOCK_OP_INVALID, "INVALID" }, \
+ { VIRTIO_VSOCK_OP_REQUEST, "REQUEST" }, \
+ { VIRTIO_VSOCK_OP_RESPONSE, "RESPONSE" }, \
+ { VIRTIO_VSOCK_OP_RST, "RST" }, \
+ { VIRTIO_VSOCK_OP_SHUTDOWN, "SHUTDOWN" }, \
+ { VIRTIO_VSOCK_OP_RW, "RW" }, \
+ { VIRTIO_VSOCK_OP_CREDIT_UPDATE, "CREDIT_UPDATE" }, \
+ { VIRTIO_VSOCK_OP_CREDIT_REQUEST, "CREDIT_REQUEST" })
+
+TRACE_EVENT(virtio_transport_alloc_pkt,
+ TP_PROTO(
+ __u32 src_cid, __u32 src_port,
+ __u32 dst_cid, __u32 dst_port,
+ __u32 len,
+ __u16 type,
+ __u16 op,
+ __u32 flags
+ ),
+ TP_ARGS(
+ src_cid, src_port,
+ dst_cid, dst_port,
+ len,
+ type,
+ op,
+ flags
+ ),
+ TP_STRUCT__entry(
+ __field(__u32, src_cid)
+ __field(__u32, src_port)
+ __field(__u32, dst_cid)
+ __field(__u32, dst_port)
+ __field(__u32, len)
+ __field(__u16, type)
+ __field(__u16, op)
+ __field(__u32, flags)
+ ),
+ TP_fast_assign(
+ __entry->src_cid = src_cid;
+ __entry->src_port = src_port;
+ __entry->dst_cid = dst_cid;
+ __entry->dst_port = dst_port;
+ __entry->len = len;
+ __entry->type = type;
+ __entry->op = op;
+ __entry->flags = flags;
+ ),
+ TP_printk("%u:%u -> %u:%u len=%u type=%s op=%s flags=%#x",
+ __entry->src_cid, __entry->src_port,
+ __entry->dst_cid, __entry->dst_port,
+ __entry->len,
+ show_type(__entry->type),
+ show_op(__entry->op),
+ __entry->flags)
+);
+
+TRACE_EVENT(virtio_transport_recv_pkt,
+ TP_PROTO(
+ __u32 src_cid, __u32 src_port,
+ __u32 dst_cid, __u32 dst_port,
+ __u32 len,
+ __u16 type,
+ __u16 op,
+ __u32 flags,
+ __u32 buf_alloc,
+ __u32 fwd_cnt
+ ),
+ TP_ARGS(
+ src_cid, src_port,
+ dst_cid, dst_port,
+ len,
+ type,
+ op,
+ flags,
+ buf_alloc,
+ fwd_cnt
+ ),
+ TP_STRUCT__entry(
+ __field(__u32, src_cid)
+ __field(__u32, src_port)
+ __field(__u32, dst_cid)
+ __field(__u32, dst_port)
+ __field(__u32, len)
+ __field(__u16, type)
+ __field(__u16, op)
+ __field(__u32, flags)
+ __field(__u32, buf_alloc)
+ __field(__u32, fwd_cnt)
+ ),
+ TP_fast_assign(
+ __entry->src_cid = src_cid;
+ __entry->src_port = src_port;
+ __entry->dst_cid = dst_cid;
+ __entry->dst_port = dst_port;
+ __entry->len = len;
+ __entry->type = type;
+ __entry->op = op;
+ __entry->flags = flags;
+ __entry->buf_alloc = buf_alloc;
+ __entry->fwd_cnt = fwd_cnt;
+ ),
+ TP_printk("%u:%u -> %u:%u len=%u type=%s op=%s flags=%#x "
+ "buf_alloc=%u fwd_cnt=%u",
+ __entry->src_cid, __entry->src_port,
+ __entry->dst_cid, __entry->dst_port,
+ __entry->len,
+ show_type(__entry->type),
+ show_op(__entry->op),
+ __entry->flags,
+ __entry->buf_alloc,
+ __entry->fwd_cnt)
+);
+
+#endif /* _TRACE_VSOCK_VIRTIO_TRANSPORT_COMMON_H */
+
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE vsock_virtio_transport_common
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h
index 77925f5..16dcf5d 100644
--- a/include/uapi/linux/virtio_ids.h
+++ b/include/uapi/linux/virtio_ids.h
@@ -39,6 +39,7 @@
#define VIRTIO_ID_9P 9 /* 9p virtio console */
#define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */
#define VIRTIO_ID_CAIF 12 /* Virtio caif */
+#define VIRTIO_ID_VSOCK 13 /* virtio vsock transport */
#define VIRTIO_ID_GPU 16 /* virtio GPU */
#define VIRTIO_ID_INPUT 18 /* virtio input */
diff --git a/include/uapi/linux/virtio_vsock.h b/include/uapi/linux/virtio_vsock.h
new file mode 100644
index 0000000..ac6483d
--- /dev/null
+++ b/include/uapi/linux/virtio_vsock.h
@@ -0,0 +1,87 @@
+/*
+ * This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
+ * anyone can use the definitions to implement compatible drivers/servers:
+ *
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * Copyright (C) Red Hat, Inc., 2013-2015
+ * Copyright (C) Asias He <asias@redhat.com>, 2013
+ * Copyright (C) Stefan Hajnoczi <stefanha@redhat.com>, 2015
+ */
+
+#ifndef _UAPI_LINUX_VIRTIO_VSOCK_H
+#define _UAPI_LINUX_VIRTIO_VOSCK_H
+
+#include <linux/types.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+
+struct virtio_vsock_config {
+ __le32 guest_cid;
+ __le32 max_virtqueue_pairs;
+};
+
+struct virtio_vsock_hdr {
+ __le32 src_cid;
+ __le32 src_port;
+ __le32 dst_cid;
+ __le32 dst_port;
+ __le32 len;
+ __le16 type; /* enum virtio_vsock_type */
+ __le16 op; /* enum virtio_vsock_op */
+ __le32 flags;
+ __le32 buf_alloc;
+ __le32 fwd_cnt;
+};
+
+enum virtio_vsock_type {
+ VIRTIO_VSOCK_TYPE_STREAM = 1,
+};
+
+enum virtio_vsock_op {
+ VIRTIO_VSOCK_OP_INVALID = 0,
+
+ /* Connect operations */
+ VIRTIO_VSOCK_OP_REQUEST = 1,
+ VIRTIO_VSOCK_OP_RESPONSE = 2,
+ VIRTIO_VSOCK_OP_RST = 3,
+ VIRTIO_VSOCK_OP_SHUTDOWN = 4,
+
+ /* To send payload */
+ VIRTIO_VSOCK_OP_RW = 5,
+
+ /* Tell the peer our credit info */
+ VIRTIO_VSOCK_OP_CREDIT_UPDATE = 6,
+ /* Request the peer to send the credit info to us */
+ VIRTIO_VSOCK_OP_CREDIT_REQUEST = 7,
+};
+
+/* VIRTIO_VSOCK_OP_SHUTDOWN flags values */
+enum virtio_vsock_shutdown {
+ VIRTIO_VSOCK_SHUTDOWN_RCV = 1,
+ VIRTIO_VSOCK_SHUTDOWN_SEND = 2,
+};
+
+#endif /* _UAPI_LINUX_VIRTIO_VSOCK_H */
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
new file mode 100644
index 0000000..000f12b
--- /dev/null
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -0,0 +1,834 @@
+/*
+ * common code for virtio vsock
+ *
+ * Copyright (C) 2013-2015 Red Hat, Inc.
+ * Author: Asias He <asias@redhat.com>
+ * Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/list.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_vsock.h>
+
+#include <net/sock.h>
+#include <net/af_vsock.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/vsock_virtio_transport_common.h>
+
+static const struct virtio_transport *virtio_transport_get_ops(void)
+{
+ const struct vsock_transport *t = vsock_core_get_transport();
+
+ return container_of(t, struct virtio_transport, transport);
+}
+
+static int virtio_transport_send_pkt(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt_info *info)
+{
+ return virtio_transport_get_ops()->send_pkt(vsk, info);
+}
+
+static int virtio_transport_send_pkt_no_sock(struct virtio_vsock_pkt *pkt)
+{
+ return virtio_transport_get_ops()->send_pkt_no_sock(pkt);
+}
+
+struct virtio_vsock_pkt *
+virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
+ size_t len,
+ u32 src_cid,
+ u32 src_port,
+ u32 dst_cid,
+ u32 dst_port)
+{
+ struct virtio_vsock_pkt *pkt;
+ int err;
+
+ pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return NULL;
+
+ pkt->hdr.type = cpu_to_le16(info->type);
+ pkt->hdr.op = cpu_to_le16(info->op);
+ pkt->hdr.src_cid = cpu_to_le32(src_cid);
+ pkt->hdr.src_port = cpu_to_le32(src_port);
+ pkt->hdr.dst_cid = cpu_to_le32(dst_cid);
+ pkt->hdr.dst_port = cpu_to_le32(dst_port);
+ pkt->hdr.flags = cpu_to_le32(info->flags);
+ pkt->len = len;
+ pkt->hdr.len = cpu_to_le32(len);
+
+ if (info->msg && len > 0) {
+ pkt->buf = kmalloc(len, GFP_KERNEL);
+ if (!pkt->buf)
+ goto out_pkt;
+ err = memcpy_from_msg(pkt->buf, info->msg, len);
+ if (err)
+ goto out;
+ }
+
+ trace_virtio_transport_alloc_pkt(src_cid, src_port,
+ dst_cid, dst_port,
+ len,
+ info->type,
+ info->op,
+ info->flags);
+
+ return pkt;
+
+out:
+ kfree(pkt->buf);
+out_pkt:
+ kfree(pkt);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_alloc_pkt);
+
+static void virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
+ struct virtio_vsock_pkt *pkt)
+{
+ vvs->rx_bytes += pkt->len;
+}
+
+static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
+ struct virtio_vsock_pkt *pkt)
+{
+ vvs->rx_bytes -= pkt->len;
+ vvs->fwd_cnt += pkt->len;
+}
+
+void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
+{
+ mutex_lock(&vvs->tx_lock);
+ pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
+ pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
+ mutex_unlock(&vvs->tx_lock);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
+
+u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit)
+{
+ u32 ret;
+
+ mutex_lock(&vvs->tx_lock);
+ ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
+ if (ret > credit)
+ ret = credit;
+ vvs->tx_cnt += ret;
+ mutex_unlock(&vvs->tx_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
+
+void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
+{
+ mutex_lock(&vvs->tx_lock);
+ vvs->tx_cnt -= credit;
+ mutex_unlock(&vvs->tx_lock);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
+
+static int virtio_transport_send_credit_update(struct vsock_sock *vsk,
+ int type,
+ struct virtio_vsock_hdr *hdr)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
+ .type = type,
+ };
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+
+static ssize_t
+virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ struct virtio_vsock_pkt *pkt;
+ size_t bytes, total = 0;
+ int err = -EFAULT;
+
+ mutex_lock(&vvs->rx_lock);
+ while (total < len &&
+ vvs->rx_bytes > 0 &&
+ !list_empty(&vvs->rx_queue)) {
+ pkt = list_first_entry(&vvs->rx_queue,
+ struct virtio_vsock_pkt, list);
+
+ bytes = len - total;
+ if (bytes > pkt->len - pkt->off)
+ bytes = pkt->len - pkt->off;
+
+ err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
+ if (err)
+ goto out;
+ total += bytes;
+ pkt->off += bytes;
+ if (pkt->off == pkt->len) {
+ virtio_transport_dec_rx_pkt(vvs, pkt);
+ list_del(&pkt->list);
+ virtio_transport_free_pkt(pkt);
+ }
+ }
+ mutex_unlock(&vvs->rx_lock);
+
+ /* Send a credit pkt to peer */
+ virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
+ NULL);
+
+ return total;
+
+out:
+ mutex_unlock(&vvs->rx_lock);
+ if (total)
+ err = total;
+ return err;
+}
+
+ssize_t
+virtio_transport_stream_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len, int flags)
+{
+ if (flags & MSG_PEEK)
+ return -EOPNOTSUPP;
+
+ return virtio_transport_stream_do_dequeue(vsk, msg, len);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
+
+int
+virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len, int flags)
+{
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
+
+s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ s64 bytes;
+
+ mutex_lock(&vvs->rx_lock);
+ bytes = vvs->rx_bytes;
+ mutex_unlock(&vvs->rx_lock);
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
+
+static s64 virtio_transport_has_space(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ s64 bytes;
+
+ bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
+ if (bytes < 0)
+ bytes = 0;
+
+ return bytes;
+}
+
+s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ s64 bytes;
+
+ mutex_lock(&vvs->tx_lock);
+ bytes = virtio_transport_has_space(vsk);
+ mutex_unlock(&vvs->tx_lock);
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_has_space);
+
+int virtio_transport_do_socket_init(struct vsock_sock *vsk,
+ struct vsock_sock *psk)
+{
+ struct virtio_vsock_sock *vvs;
+
+ vvs = kzalloc(sizeof(*vvs), GFP_KERNEL);
+ if (!vvs)
+ return -ENOMEM;
+
+ vsk->trans = vvs;
+ vvs->vsk = vsk;
+ if (psk) {
+ struct virtio_vsock_sock *ptrans = psk->trans;
+
+ vvs->buf_size = ptrans->buf_size;
+ vvs->buf_size_min = ptrans->buf_size_min;
+ vvs->buf_size_max = ptrans->buf_size_max;
+ vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
+ } else {
+ vvs->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
+ vvs->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
+ vvs->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
+ }
+
+ vvs->buf_alloc = vvs->buf_size;
+
+ mutex_init(&vvs->rx_lock);
+ mutex_init(&vvs->tx_lock);
+ INIT_LIST_HEAD(&vvs->rx_queue);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
+
+u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ return vvs->buf_size;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
+
+u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ return vvs->buf_size_min;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
+
+u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ return vvs->buf_size_max;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
+
+void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val < vvs->buf_size_min)
+ vvs->buf_size_min = val;
+ if (val > vvs->buf_size_max)
+ vvs->buf_size_max = val;
+ vvs->buf_size = val;
+ vvs->buf_alloc = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
+
+void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val > vvs->buf_size)
+ vvs->buf_size = val;
+ vvs->buf_size_min = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
+
+void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val < vvs->buf_size)
+ vvs->buf_size = val;
+ vvs->buf_size_max = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
+
+int
+virtio_transport_notify_poll_in(struct vsock_sock *vsk,
+ size_t target,
+ bool *data_ready_now)
+{
+ if (vsock_stream_has_data(vsk))
+ *data_ready_now = true;
+ else
+ *data_ready_now = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_in);
+
+int
+virtio_transport_notify_poll_out(struct vsock_sock *vsk,
+ size_t target,
+ bool *space_avail_now)
+{
+ s64 free_space;
+
+ free_space = vsock_stream_has_space(vsk);
+ if (free_space > 0)
+ *space_avail_now = true;
+ else if (free_space == 0)
+ *space_avail_now = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_out);
+
+int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_init);
+
+int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_block);
+
+int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_dequeue);
+
+int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
+ size_t target, ssize_t copied, bool data_read,
+ struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_post_dequeue);
+
+int virtio_transport_notify_send_init(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_init);
+
+int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_block);
+
+int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_enqueue);
+
+int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
+ ssize_t written, struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
+
+u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ return vvs->buf_size;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);
+
+bool virtio_transport_stream_is_active(struct vsock_sock *vsk)
+{
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
+
+bool virtio_transport_stream_allow(u32 cid, u32 port)
+{
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
+
+int virtio_transport_dgram_bind(struct vsock_sock *vsk,
+ struct sockaddr_vm *addr)
+{
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
+
+bool virtio_transport_dgram_allow(u32 cid, u32 port)
+{
+ return false;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
+
+int virtio_transport_connect(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_REQUEST,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ };
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_connect);
+
+int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_SHUTDOWN,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .flags = (mode & RCV_SHUTDOWN ?
+ VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
+ (mode & SEND_SHUTDOWN ?
+ VIRTIO_VSOCK_SHUTDOWN_SEND : 0),
+ };
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
+
+void virtio_transport_release(struct vsock_sock *vsk)
+{
+ struct sock *sk = &vsk->sk;
+
+ /* Tell other side to terminate connection */
+ if (sk->sk_type == SOCK_STREAM &&
+ vsk->peer_shutdown != SHUTDOWN_MASK &&
+ sk->sk_state == SS_CONNECTED)
+ (void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_release);
+
+int
+virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
+ struct sockaddr_vm *remote_addr,
+ struct msghdr *msg,
+ size_t dgram_len)
+{
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
+
+ssize_t
+virtio_transport_stream_enqueue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RW,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .msg = msg,
+ .pkt_len = len,
+ };
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
+
+void virtio_transport_destruct(struct vsock_sock *vsk)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+
+ kfree(vvs);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_destruct);
+
+static int virtio_transport_send_reset(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RST,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ };
+
+ /* Send RST only if the original pkt is not a RST pkt */
+ if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
+ return 0;
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+
+/* Normally packets are associated with a socket. There may be no socket if an
+ * attempt was made to connect to a socket that does not exist.
+ */
+static int virtio_transport_send_reset_no_sock(struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RST,
+ .type = le16_to_cpu(pkt->hdr.type),
+ };
+
+ /* Send RST only if the original pkt is not a RST pkt */
+ if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
+ return 0;
+
+ pkt = virtio_transport_alloc_pkt(&info, 0,
+ le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.dst_port),
+ le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port));
+ if (!pkt)
+ return -ENOMEM;
+
+ return virtio_transport_send_pkt_no_sock(pkt);
+}
+
+static int
+virtio_transport_recv_connecting(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ int err;
+ int skerr;
+
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_RESPONSE:
+ sk->sk_state = SS_CONNECTED;
+ sk->sk_socket->state = SS_CONNECTED;
+ vsock_insert_connected(vsk);
+ sk->sk_state_change(sk);
+ break;
+ case VIRTIO_VSOCK_OP_INVALID:
+ break;
+ case VIRTIO_VSOCK_OP_RST:
+ skerr = ECONNRESET;
+ err = 0;
+ goto destroy;
+ default:
+ skerr = EPROTO;
+ err = -EINVAL;
+ goto destroy;
+ }
+ return 0;
+
+destroy:
+ virtio_transport_send_reset(vsk, pkt);
+ sk->sk_state = SS_UNCONNECTED;
+ sk->sk_err = skerr;
+ sk->sk_error_report(sk);
+ return err;
+}
+
+static int
+virtio_transport_recv_connected(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ int err = 0;
+
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_RW:
+ pkt->len = le32_to_cpu(pkt->hdr.len);
+ pkt->off = 0;
+
+ mutex_lock(&vvs->rx_lock);
+ virtio_transport_inc_rx_pkt(vvs, pkt);
+ list_add_tail(&pkt->list, &vvs->rx_queue);
+ mutex_unlock(&vvs->rx_lock);
+
+ sk->sk_data_ready(sk);
+ return err;
+ case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
+ sk->sk_write_space(sk);
+ break;
+ case VIRTIO_VSOCK_OP_SHUTDOWN:
+ if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
+ vsk->peer_shutdown |= RCV_SHUTDOWN;
+ if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
+ vsk->peer_shutdown |= SEND_SHUTDOWN;
+ if (vsk->peer_shutdown == SHUTDOWN_MASK &&
+ vsock_stream_has_data(vsk) <= 0)
+ sk->sk_state = SS_DISCONNECTING;
+ if (le32_to_cpu(pkt->hdr.flags))
+ sk->sk_state_change(sk);
+ break;
+ case VIRTIO_VSOCK_OP_RST:
+ sock_set_flag(sk, SOCK_DONE);
+ vsk->peer_shutdown = SHUTDOWN_MASK;
+ if (vsock_stream_has_data(vsk) <= 0)
+ sk->sk_state = SS_DISCONNECTING;
+ sk->sk_state_change(sk);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ virtio_transport_free_pkt(pkt);
+ return err;
+}
+
+static int
+virtio_transport_send_response(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RESPONSE,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .remote_cid = le32_to_cpu(pkt->hdr.src_cid),
+ .remote_port = le32_to_cpu(pkt->hdr.src_port),
+ };
+
+ return virtio_transport_send_pkt(vsk, &info);
+}
+
+/* Handle server socket */
+static int
+virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct vsock_sock *vchild;
+ struct sock *child;
+
+ if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
+ virtio_transport_send_reset(vsk, pkt);
+ return -EINVAL;
+ }
+
+ if (sk_acceptq_is_full(sk)) {
+ virtio_transport_send_reset(vsk, pkt);
+ return -ENOMEM;
+ }
+
+ child = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
+ sk->sk_type, 0);
+ if (!child) {
+ virtio_transport_send_reset(vsk, pkt);
+ return -ENOMEM;
+ }
+
+ sk->sk_ack_backlog++;
+
+ lock_sock(child);
+
+ child->sk_state = SS_CONNECTED;
+
+ vchild = vsock_sk(child);
+ vsock_addr_init(&vchild->local_addr, le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.dst_port));
+ vsock_addr_init(&vchild->remote_addr, le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port));
+
+ vsock_insert_connected(vchild);
+ vsock_enqueue_accept(sk, child);
+ virtio_transport_send_response(vchild, pkt);
+
+ release_sock(child);
+
+ sk->sk_data_ready(sk);
+ return 0;
+}
+
+static void virtio_transport_space_update(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ bool space_available;
+
+ /* buf_alloc and fwd_cnt is always included in the hdr */
+ mutex_lock(&vvs->tx_lock);
+ vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
+ vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
+ space_available = virtio_transport_has_space(vsk);
+ mutex_unlock(&vvs->tx_lock);
+
+ if (space_available)
+ sk->sk_write_space(sk);
+}
+
+/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
+ * lock.
+ */
+void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
+{
+ struct sockaddr_vm src, dst;
+ struct vsock_sock *vsk;
+ struct sock *sk;
+
+ vsock_addr_init(&src, le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port));
+ vsock_addr_init(&dst, le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.dst_port));
+
+ trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
+ dst.svm_cid, dst.svm_port,
+ le32_to_cpu(pkt->hdr.len),
+ le16_to_cpu(pkt->hdr.type),
+ le16_to_cpu(pkt->hdr.op),
+ le32_to_cpu(pkt->hdr.flags),
+ le32_to_cpu(pkt->hdr.buf_alloc),
+ le32_to_cpu(pkt->hdr.fwd_cnt));
+
+ if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
+ (void)virtio_transport_send_reset_no_sock(pkt);
+ goto free_pkt;
+ }
+
+ /* The socket must be in connected or bound table
+ * otherwise send reset back
+ */
+ sk = vsock_find_connected_socket(&src, &dst);
+ if (!sk) {
+ sk = vsock_find_bound_socket(&dst);
+ if (!sk) {
+ (void)virtio_transport_send_reset_no_sock(pkt);
+ goto free_pkt;
+ }
+ }
+
+ vsk = vsock_sk(sk);
+
+ virtio_transport_space_update(sk, pkt);
+
+ lock_sock(sk);
+ switch (sk->sk_state) {
+ case VSOCK_SS_LISTEN:
+ virtio_transport_recv_listen(sk, pkt);
+ virtio_transport_free_pkt(pkt);
+ break;
+ case SS_CONNECTING:
+ virtio_transport_recv_connecting(sk, pkt);
+ virtio_transport_free_pkt(pkt);
+ break;
+ case SS_CONNECTED:
+ virtio_transport_recv_connected(sk, pkt);
+ break;
+ default:
+ virtio_transport_free_pkt(pkt);
+ break;
+ }
+ release_sock(sk);
+
+ /* Release refcnt obtained when we fetched this socket out of the
+ * bound or connected list.
+ */
+ sock_put(sk);
+ return;
+
+free_pkt:
+ virtio_transport_free_pkt(pkt);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
+
+void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
+{
+ kfree(pkt->buf);
+ kfree(pkt);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Asias He");
+MODULE_DESCRIPTION("common code for virtio vsock");
--
2.5.0
^ permalink raw reply related
* [RFC v4 3/5] VSOCK: Introduce virtio_transport.ko
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Asias He, Christoffer Dall, matt.ma
In-Reply-To: <1450775258-18287-1-git-send-email-stefanha@redhat.com>
From: Asias He <asias@redhat.com>
VM sockets virtio transport implementation. This driver runs in the
guest.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
v4:
* Add MAINTAINERS file entry
* Drop short/long rx packets
* checkpatch.pl cleanups
* Clarify locking in struct virtio_vsock
* Narrow local variable scopes as suggested by Alex Bennee
* Call wake_up() after decrementing total_tx_buf to avoid deadlock
v2:
* Fix total_tx_buf accounting
* Add virtio_transport global mutex to prevent races
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
MAINTAINERS | 1 +
net/vmw_vsock/virtio_transport.c | 481 +++++++++++++++++++++++++++++++++++++++
2 files changed, 482 insertions(+)
create mode 100644 net/vmw_vsock/virtio_transport.c
diff --git a/MAINTAINERS b/MAINTAINERS
index d42db78..67d8504 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11369,6 +11369,7 @@ S: Maintained
F: include/linux/virtio_vsock.h
F: include/uapi/linux/virtio_vsock.h
F: net/vmw_vsock/virtio_transport_common.c
+F: net/vmw_vsock/virtio_transport.c
VIRTUAL SERIO DEVICE DRIVER
M: Stephen Chandler Paul <thatslyude@gmail.com>
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
new file mode 100644
index 0000000..e4787bf
--- /dev/null
+++ b/net/vmw_vsock/virtio_transport.c
@@ -0,0 +1,481 @@
+/*
+ * virtio transport for vsock
+ *
+ * Copyright (C) 2013-2015 Red Hat, Inc.
+ * Author: Asias He <asias@redhat.com>
+ * Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * Some of the code is take from Gerd Hoffmann <kraxel@redhat.com>'s
+ * early virtio-vsock proof-of-concept bits.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_vsock.h>
+#include <net/sock.h>
+#include <linux/mutex.h>
+#include <net/af_vsock.h>
+
+static struct workqueue_struct *virtio_vsock_workqueue;
+static struct virtio_vsock *the_virtio_vsock;
+static DEFINE_MUTEX(the_virtio_vsock_mutex); /* protects the_virtio_vsock */
+static void virtio_vsock_rx_fill(struct virtio_vsock *vsock);
+
+struct virtio_vsock {
+ struct virtio_device *vdev;
+ struct virtqueue *vqs[VSOCK_VQ_MAX];
+
+ /* Virtqueue processing is deferred to a workqueue */
+ struct work_struct tx_work;
+ struct work_struct rx_work;
+
+ wait_queue_head_t tx_wait; /* for waiting for tx resources */
+
+ /* The following fields are protected by tx_lock. vqs[VSOCK_VQ_TX]
+ * must be accessed with tx_lock held.
+ */
+ struct mutex tx_lock;
+ u32 total_tx_buf;
+
+ /* The following fields are protected by rx_lock. vqs[VSOCK_VQ_RX]
+ * must be accessed with rx_lock held.
+ */
+ struct mutex rx_lock;
+ int rx_buf_nr;
+ int rx_buf_max_nr;
+
+ u32 guest_cid;
+};
+
+static struct virtio_vsock *virtio_vsock_get(void)
+{
+ return the_virtio_vsock;
+}
+
+static u32 virtio_transport_get_local_cid(void)
+{
+ struct virtio_vsock *vsock = virtio_vsock_get();
+
+ return vsock->guest_cid;
+}
+
+static int
+virtio_transport_send_one_pkt(struct virtio_vsock *vsock,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct scatterlist hdr, buf, *sgs[2];
+ int ret, in_sg = 0, out_sg = 0;
+ struct virtqueue *vq;
+ DEFINE_WAIT(wait);
+
+ vq = vsock->vqs[VSOCK_VQ_TX];
+
+ /* Put pkt in the virtqueue */
+ sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
+ sgs[out_sg++] = &hdr;
+ if (pkt->buf) {
+ sg_init_one(&buf, pkt->buf, pkt->len);
+ sgs[out_sg++] = &buf;
+ }
+
+ mutex_lock(&vsock->tx_lock);
+ while ((ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt,
+ GFP_KERNEL)) < 0) {
+ prepare_to_wait_exclusive(&vsock->tx_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ mutex_unlock(&vsock->tx_lock);
+ schedule();
+ mutex_lock(&vsock->tx_lock);
+ finish_wait(&vsock->tx_wait, &wait);
+ }
+ virtqueue_kick(vq);
+ mutex_unlock(&vsock->tx_lock);
+
+ return pkt->len;
+}
+
+static int
+virtio_transport_send_pkt_no_sock(struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_vsock *vsock;
+
+ vsock = virtio_vsock_get();
+ if (!vsock) {
+ virtio_transport_free_pkt(pkt);
+ return -ENODEV;
+ }
+
+ return virtio_transport_send_one_pkt(vsock, pkt);
+}
+
+static int
+virtio_transport_send_pkt(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt_info *info)
+{
+ u32 src_cid, src_port, dst_cid, dst_port;
+ struct virtio_vsock_sock *vvs;
+ struct virtio_vsock_pkt *pkt;
+ struct virtio_vsock *vsock;
+ u32 pkt_len = info->pkt_len;
+ DEFINE_WAIT(wait);
+
+ vsock = virtio_vsock_get();
+ if (!vsock)
+ return -ENODEV;
+
+ src_cid = virtio_transport_get_local_cid();
+ src_port = vsk->local_addr.svm_port;
+ if (!info->remote_cid) {
+ dst_cid = vsk->remote_addr.svm_cid;
+ dst_port = vsk->remote_addr.svm_port;
+ } else {
+ dst_cid = info->remote_cid;
+ dst_port = info->remote_port;
+ }
+
+ vvs = vsk->trans;
+
+ if (pkt_len > VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE)
+ pkt_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
+ pkt_len = virtio_transport_get_credit(vvs, pkt_len);
+ /* Do not send zero length OP_RW pkt*/
+ if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
+ return pkt_len;
+
+ /* Respect global tx buf limitation */
+ mutex_lock(&vsock->tx_lock);
+ while (pkt_len + vsock->total_tx_buf > VIRTIO_VSOCK_MAX_TX_BUF_SIZE) {
+ prepare_to_wait_exclusive(&vsock->tx_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ mutex_unlock(&vsock->tx_lock);
+ schedule();
+ mutex_lock(&vsock->tx_lock);
+ finish_wait(&vsock->tx_wait, &wait);
+ }
+ vsock->total_tx_buf += pkt_len;
+ mutex_unlock(&vsock->tx_lock);
+
+ pkt = virtio_transport_alloc_pkt(info, pkt_len,
+ src_cid, src_port,
+ dst_cid, dst_port);
+ if (!pkt) {
+ mutex_lock(&vsock->tx_lock);
+ vsock->total_tx_buf -= pkt_len;
+ mutex_unlock(&vsock->tx_lock);
+ virtio_transport_put_credit(vvs, pkt_len);
+ wake_up(&vsock->tx_wait);
+ return -ENOMEM;
+ }
+
+ virtio_transport_inc_tx_pkt(vvs, pkt);
+
+ return virtio_transport_send_one_pkt(vsock, pkt);
+}
+
+static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
+{
+ int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
+ struct virtio_vsock_pkt *pkt;
+ struct scatterlist hdr, buf, *sgs[2];
+ struct virtqueue *vq;
+ int ret;
+
+ vq = vsock->vqs[VSOCK_VQ_RX];
+
+ do {
+ pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ break;
+
+ pkt->buf = kmalloc(buf_len, GFP_KERNEL);
+ if (!pkt->buf) {
+ virtio_transport_free_pkt(pkt);
+ break;
+ }
+
+ pkt->len = buf_len;
+
+ sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
+ sgs[0] = &hdr;
+
+ sg_init_one(&buf, pkt->buf, buf_len);
+ sgs[1] = &buf;
+ ret = virtqueue_add_sgs(vq, sgs, 0, 2, pkt, GFP_KERNEL);
+ if (ret) {
+ virtio_transport_free_pkt(pkt);
+ break;
+ }
+ vsock->rx_buf_nr++;
+ } while (vq->num_free);
+ if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
+ vsock->rx_buf_max_nr = vsock->rx_buf_nr;
+ virtqueue_kick(vq);
+}
+
+static void virtio_transport_send_pkt_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, tx_work);
+ struct virtqueue *vq;
+ bool added = false;
+
+ vq = vsock->vqs[VSOCK_VQ_TX];
+ mutex_lock(&vsock->tx_lock);
+ do {
+ struct virtio_vsock_pkt *pkt;
+ unsigned int len;
+
+ virtqueue_disable_cb(vq);
+ while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) {
+ vsock->total_tx_buf -= pkt->len;
+ virtio_transport_free_pkt(pkt);
+ added = true;
+ }
+ } while (!virtqueue_enable_cb(vq));
+ mutex_unlock(&vsock->tx_lock);
+
+ if (added)
+ wake_up(&vsock->tx_wait);
+}
+
+static void virtio_transport_recv_pkt_work(struct work_struct *work)
+{
+ struct virtio_vsock *vsock =
+ container_of(work, struct virtio_vsock, rx_work);
+ struct virtqueue *vq;
+
+ vq = vsock->vqs[VSOCK_VQ_RX];
+ mutex_lock(&vsock->rx_lock);
+ do {
+ struct virtio_vsock_pkt *pkt;
+ unsigned int len;
+
+ virtqueue_disable_cb(vq);
+ while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) {
+ vsock->rx_buf_nr--;
+
+ /* Drop short/long packets */
+ if (unlikely(len < sizeof(pkt->hdr) ||
+ len > sizeof(pkt->hdr) + pkt->len)) {
+ virtio_transport_free_pkt(pkt);
+ continue;
+ }
+
+ pkt->len = len - sizeof(pkt->hdr);
+ virtio_transport_recv_pkt(pkt);
+ }
+ } while (!virtqueue_enable_cb(vq));
+
+ if (vsock->rx_buf_nr < vsock->rx_buf_max_nr / 2)
+ virtio_vsock_rx_fill(vsock);
+ mutex_unlock(&vsock->rx_lock);
+}
+
+static void virtio_vsock_ctrl_done(struct virtqueue *vq)
+{
+}
+
+static void virtio_vsock_tx_done(struct virtqueue *vq)
+{
+ struct virtio_vsock *vsock = vq->vdev->priv;
+
+ if (!vsock)
+ return;
+ queue_work(virtio_vsock_workqueue, &vsock->tx_work);
+}
+
+static void virtio_vsock_rx_done(struct virtqueue *vq)
+{
+ struct virtio_vsock *vsock = vq->vdev->priv;
+
+ if (!vsock)
+ return;
+ queue_work(virtio_vsock_workqueue, &vsock->rx_work);
+}
+
+static struct virtio_transport virtio_transport = {
+ .transport = {
+ .get_local_cid = virtio_transport_get_local_cid,
+
+ .init = virtio_transport_do_socket_init,
+ .destruct = virtio_transport_destruct,
+ .release = virtio_transport_release,
+ .connect = virtio_transport_connect,
+ .shutdown = virtio_transport_shutdown,
+
+ .dgram_bind = virtio_transport_dgram_bind,
+ .dgram_dequeue = virtio_transport_dgram_dequeue,
+ .dgram_enqueue = virtio_transport_dgram_enqueue,
+ .dgram_allow = virtio_transport_dgram_allow,
+
+ .stream_dequeue = virtio_transport_stream_dequeue,
+ .stream_enqueue = virtio_transport_stream_enqueue,
+ .stream_has_data = virtio_transport_stream_has_data,
+ .stream_has_space = virtio_transport_stream_has_space,
+ .stream_rcvhiwat = virtio_transport_stream_rcvhiwat,
+ .stream_is_active = virtio_transport_stream_is_active,
+ .stream_allow = virtio_transport_stream_allow,
+
+ .notify_poll_in = virtio_transport_notify_poll_in,
+ .notify_poll_out = virtio_transport_notify_poll_out,
+ .notify_recv_init = virtio_transport_notify_recv_init,
+ .notify_recv_pre_block = virtio_transport_notify_recv_pre_block,
+ .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue,
+ .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
+ .notify_send_init = virtio_transport_notify_send_init,
+ .notify_send_pre_block = virtio_transport_notify_send_pre_block,
+ .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
+ .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
+
+ .set_buffer_size = virtio_transport_set_buffer_size,
+ .set_min_buffer_size = virtio_transport_set_min_buffer_size,
+ .set_max_buffer_size = virtio_transport_set_max_buffer_size,
+ .get_buffer_size = virtio_transport_get_buffer_size,
+ .get_min_buffer_size = virtio_transport_get_min_buffer_size,
+ .get_max_buffer_size = virtio_transport_get_max_buffer_size,
+ },
+
+ .send_pkt = virtio_transport_send_pkt,
+ .send_pkt_no_sock = virtio_transport_send_pkt_no_sock,
+};
+
+static int virtio_vsock_probe(struct virtio_device *vdev)
+{
+ vq_callback_t *callbacks[] = {
+ virtio_vsock_ctrl_done,
+ virtio_vsock_rx_done,
+ virtio_vsock_tx_done,
+ };
+ static const char * const names[] = {
+ "ctrl",
+ "rx",
+ "tx",
+ };
+ struct virtio_vsock *vsock = NULL;
+ u32 guest_cid;
+ int ret;
+
+ ret = mutex_lock_interruptible(&the_virtio_vsock_mutex);
+ if (ret)
+ return ret;
+
+ /* Only one virtio-vsock device per guest is supported */
+ if (the_virtio_vsock) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ vsock = kzalloc(sizeof(*vsock), GFP_KERNEL);
+ if (!vsock) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ vsock->vdev = vdev;
+
+ ret = vsock->vdev->config->find_vqs(vsock->vdev, VSOCK_VQ_MAX,
+ vsock->vqs, callbacks, names);
+ if (ret < 0)
+ goto out;
+
+ vdev->config->get(vdev, offsetof(struct virtio_vsock_config, guest_cid),
+ &guest_cid, sizeof(guest_cid));
+ vsock->guest_cid = le32_to_cpu(guest_cid);
+
+ ret = vsock_core_init(&virtio_transport.transport);
+ if (ret < 0)
+ goto out_vqs;
+
+ vsock->rx_buf_nr = 0;
+ vsock->rx_buf_max_nr = 0;
+
+ vdev->priv = vsock;
+ the_virtio_vsock = vsock;
+ init_waitqueue_head(&vsock->tx_wait);
+ mutex_init(&vsock->tx_lock);
+ mutex_init(&vsock->rx_lock);
+ INIT_WORK(&vsock->rx_work, virtio_transport_recv_pkt_work);
+ INIT_WORK(&vsock->tx_work, virtio_transport_send_pkt_work);
+
+ mutex_lock(&vsock->rx_lock);
+ virtio_vsock_rx_fill(vsock);
+ mutex_unlock(&vsock->rx_lock);
+
+ mutex_unlock(&the_virtio_vsock_mutex);
+ return 0;
+
+out_vqs:
+ vsock->vdev->config->del_vqs(vsock->vdev);
+out:
+ kfree(vsock);
+ mutex_unlock(&the_virtio_vsock_mutex);
+ return ret;
+}
+
+static void virtio_vsock_remove(struct virtio_device *vdev)
+{
+ struct virtio_vsock *vsock = vdev->priv;
+
+ flush_work(&vsock->rx_work);
+ flush_work(&vsock->tx_work);
+
+ vdev->config->reset(vdev);
+
+ mutex_lock(&the_virtio_vsock_mutex);
+ the_virtio_vsock = NULL;
+ vsock_core_exit();
+ mutex_unlock(&the_virtio_vsock_mutex);
+
+ vdev->config->del_vqs(vdev);
+
+ kfree(vsock);
+}
+
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_VSOCK, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static unsigned int features[] = {
+};
+
+static struct virtio_driver virtio_vsock_driver = {
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .id_table = id_table,
+ .probe = virtio_vsock_probe,
+ .remove = virtio_vsock_remove,
+};
+
+static int __init virtio_vsock_init(void)
+{
+ int ret;
+
+ virtio_vsock_workqueue = alloc_workqueue("virtio_vsock", 0, 0);
+ if (!virtio_vsock_workqueue)
+ return -ENOMEM;
+ ret = register_virtio_driver(&virtio_vsock_driver);
+ if (ret)
+ destroy_workqueue(virtio_vsock_workqueue);
+ return ret;
+}
+
+static void __exit virtio_vsock_exit(void)
+{
+ unregister_virtio_driver(&virtio_vsock_driver);
+ destroy_workqueue(virtio_vsock_workqueue);
+}
+
+module_init(virtio_vsock_init);
+module_exit(virtio_vsock_exit);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Asias He");
+MODULE_DESCRIPTION("virtio transport for vsock");
+MODULE_DEVICE_TABLE(virtio, id_table);
--
2.5.0
^ permalink raw reply related
* [RFC v4 4/5] VSOCK: Introduce vhost_vsock.ko
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Asias He, Christoffer Dall, matt.ma
In-Reply-To: <1450775258-18287-1-git-send-email-stefanha@redhat.com>
From: Asias He <asias@redhat.com>
VM sockets vhost transport implementation. This driver runs on the
host.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
v4:
* Add MAINTAINERS file entry
* virtqueue used len is now sizeof(pkt->hdr) + pkt->len instead of just
pkt->len
* checkpatch.pl cleanups
* Clarify struct vhost_vsock locking
* Add comments about optimization that disables virtqueue notify
* Drop unused vhost_vsock_handle_ctl_kick()
* Call wake_up() after decrementing total_tx_buf to prevent deadlock
v3:
* Remove unneeded variable used to store return value
(Fengguang Wu <fengguang.wu@intel.com> and Julia Lawall
<julia.lawall@lip6.fr>)
v2:
* Add missing total_tx_buf decrement
* Support flexible rx/tx descriptor layout
* Refuse to assign reserved CIDs
* Refuse guest CID if already in use
* Only accept correctly addressed packets
vhost: checkpatch.pl cleanups
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
MAINTAINERS | 2 +
drivers/vhost/vsock.c | 607 ++++++++++++++++++++++++++++++++++++++++++++++++++
drivers/vhost/vsock.h | 4 +
3 files changed, 613 insertions(+)
create mode 100644 drivers/vhost/vsock.c
create mode 100644 drivers/vhost/vsock.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 67d8504..0181dc2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11370,6 +11370,8 @@ F: include/linux/virtio_vsock.h
F: include/uapi/linux/virtio_vsock.h
F: net/vmw_vsock/virtio_transport_common.c
F: net/vmw_vsock/virtio_transport.c
+F: drivers/vhost/vsock.c
+F: drivers/vhost/vsock.h
VIRTUAL SERIO DEVICE DRIVER
M: Stephen Chandler Paul <thatslyude@gmail.com>
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
new file mode 100644
index 0000000..2c5963c
--- /dev/null
+++ b/drivers/vhost/vsock.c
@@ -0,0 +1,607 @@
+/*
+ * vhost transport for vsock
+ *
+ * Copyright (C) 2013-2015 Red Hat, Inc.
+ * Author: Asias He <asias@redhat.com>
+ * Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <net/sock.h>
+#include <linux/virtio_vsock.h>
+#include <linux/vhost.h>
+
+#include <net/af_vsock.h>
+#include "vhost.h"
+#include "vsock.h"
+
+#define VHOST_VSOCK_DEFAULT_HOST_CID 2
+
+enum {
+ VHOST_VSOCK_FEATURES = VHOST_FEATURES,
+};
+
+/* Used to track all the vhost_vsock instances on the system. */
+static LIST_HEAD(vhost_vsock_list);
+static DEFINE_MUTEX(vhost_vsock_mutex);
+
+struct vhost_vsock {
+ struct vhost_dev dev;
+ struct vhost_virtqueue vqs[VSOCK_VQ_MAX];
+
+ /* Link to global vhost_vsock_list, protected by vhost_vsock_mutex */
+ struct list_head list;
+
+ struct vhost_work send_pkt_work;
+ wait_queue_head_t send_wait;
+
+ /* Fields protected by vqs[VSOCK_VQ_RX].mutex */
+ struct list_head send_pkt_list; /* host->guest pending packets */
+ u32 total_tx_buf;
+
+ u32 guest_cid;
+};
+
+static u32 vhost_transport_get_local_cid(void)
+{
+ return VHOST_VSOCK_DEFAULT_HOST_CID;
+}
+
+static struct vhost_vsock *vhost_vsock_get(u32 guest_cid)
+{
+ struct vhost_vsock *vsock;
+
+ mutex_lock(&vhost_vsock_mutex);
+ list_for_each_entry(vsock, &vhost_vsock_list, list) {
+ if (vsock->guest_cid == guest_cid) {
+ mutex_unlock(&vhost_vsock_mutex);
+ return vsock;
+ }
+ }
+ mutex_unlock(&vhost_vsock_mutex);
+
+ return NULL;
+}
+
+static void
+vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
+ struct vhost_virtqueue *vq)
+{
+ bool added = false;
+
+ mutex_lock(&vq->mutex);
+
+ /* Avoid further vmexits, we're already processing the virtqueue */
+ vhost_disable_notify(&vsock->dev, vq);
+
+ for (;;) {
+ struct virtio_vsock_pkt *pkt;
+ struct iov_iter iov_iter;
+ unsigned out, in;
+ size_t nbytes;
+ size_t len;
+ int head;
+
+ if (list_empty(&vsock->send_pkt_list)) {
+ vhost_enable_notify(&vsock->dev, vq);
+ break;
+ }
+
+ head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
+ &out, &in, NULL, NULL);
+ if (head < 0)
+ break;
+
+ if (head == vq->num) {
+ /* We cannot finish yet if more buffers snuck in while
+ * re-enabling notify.
+ */
+ if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
+ vhost_disable_notify(&vsock->dev, vq);
+ continue;
+ }
+ break;
+ }
+
+ pkt = list_first_entry(&vsock->send_pkt_list,
+ struct virtio_vsock_pkt, list);
+ list_del_init(&pkt->list);
+
+ if (out) {
+ virtio_transport_free_pkt(pkt);
+ vq_err(vq, "Expected 0 output buffers, got %u\n", out);
+ break;
+ }
+
+ len = iov_length(&vq->iov[out], in);
+ iov_iter_init(&iov_iter, READ, &vq->iov[out], in, len);
+
+ nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
+ if (nbytes != sizeof(pkt->hdr)) {
+ virtio_transport_free_pkt(pkt);
+ vq_err(vq, "Faulted on copying pkt hdr\n");
+ break;
+ }
+
+ nbytes = copy_to_iter(pkt->buf, pkt->len, &iov_iter);
+ if (nbytes != pkt->len) {
+ virtio_transport_free_pkt(pkt);
+ vq_err(vq, "Faulted on copying pkt buf\n");
+ break;
+ }
+
+ vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len);
+ added = true;
+
+ vsock->total_tx_buf -= pkt->len;
+
+ virtio_transport_free_pkt(pkt);
+ }
+ if (added)
+ vhost_signal(&vsock->dev, vq);
+ mutex_unlock(&vq->mutex);
+
+ if (added)
+ wake_up(&vsock->send_wait);
+}
+
+static void vhost_transport_send_pkt_work(struct vhost_work *work)
+{
+ struct vhost_virtqueue *vq;
+ struct vhost_vsock *vsock;
+
+ vsock = container_of(work, struct vhost_vsock, send_pkt_work);
+ vq = &vsock->vqs[VSOCK_VQ_RX];
+
+ vhost_transport_do_send_pkt(vsock, vq);
+}
+
+static int
+vhost_transport_send_one_pkt(struct vhost_vsock *vsock,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_RX];
+
+ /* Queue it up in vhost work */
+ mutex_lock(&vq->mutex);
+ list_add_tail(&pkt->list, &vsock->send_pkt_list);
+ vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
+ mutex_unlock(&vq->mutex);
+
+ return pkt->len;
+}
+
+static int
+vhost_transport_send_pkt_no_sock(struct virtio_vsock_pkt *pkt)
+{
+ struct vhost_vsock *vsock;
+
+ /* Find the vhost_vsock according to guest context id */
+ vsock = vhost_vsock_get(le32_to_cpu(pkt->hdr.dst_cid));
+ if (!vsock) {
+ virtio_transport_free_pkt(pkt);
+ return -ENODEV;
+ }
+
+ return vhost_transport_send_one_pkt(vsock, pkt);
+}
+
+static int
+vhost_transport_send_pkt(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt_info *info)
+{
+ u32 src_cid, src_port, dst_cid, dst_port;
+ struct virtio_vsock_sock *vvs;
+ struct virtio_vsock_pkt *pkt;
+ struct vhost_virtqueue *vq;
+ struct vhost_vsock *vsock;
+ u32 pkt_len = info->pkt_len;
+ DEFINE_WAIT(wait);
+
+ src_cid = vhost_transport_get_local_cid();
+ src_port = vsk->local_addr.svm_port;
+ if (!info->remote_cid) {
+ dst_cid = vsk->remote_addr.svm_cid;
+ dst_port = vsk->remote_addr.svm_port;
+ } else {
+ dst_cid = info->remote_cid;
+ dst_port = info->remote_port;
+ }
+
+ /* Find the vhost_vsock according to guest context id */
+ vsock = vhost_vsock_get(dst_cid);
+ if (!vsock)
+ return -ENODEV;
+
+ vvs = vsk->trans;
+ vq = &vsock->vqs[VSOCK_VQ_RX];
+
+ /* we can send less than pkt_len bytes */
+ if (pkt_len > VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE)
+ pkt_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
+
+ /* virtio_transport_get_credit might return less than pkt_len credit */
+ pkt_len = virtio_transport_get_credit(vvs, pkt_len);
+
+ /* Do not send zero length OP_RW pkt*/
+ if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
+ return pkt_len;
+
+ /* Respect global tx buf limitation */
+ mutex_lock(&vq->mutex);
+ while (pkt_len + vsock->total_tx_buf > VIRTIO_VSOCK_MAX_TX_BUF_SIZE) {
+ prepare_to_wait_exclusive(&vsock->send_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ mutex_unlock(&vq->mutex);
+ schedule();
+ mutex_lock(&vq->mutex);
+ finish_wait(&vsock->send_wait, &wait);
+ }
+ vsock->total_tx_buf += pkt_len;
+ mutex_unlock(&vq->mutex);
+
+ pkt = virtio_transport_alloc_pkt(info, pkt_len,
+ src_cid, src_port,
+ dst_cid, dst_port);
+ if (!pkt) {
+ mutex_lock(&vq->mutex);
+ vsock->total_tx_buf -= pkt_len;
+ mutex_unlock(&vq->mutex);
+ virtio_transport_put_credit(vvs, pkt_len);
+ wake_up(&vsock->send_wait);
+ return -ENOMEM;
+ }
+
+ virtio_transport_inc_tx_pkt(vvs, pkt);
+
+ return vhost_transport_send_one_pkt(vsock, pkt);
+}
+
+static struct virtio_vsock_pkt *
+vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,
+ unsigned int out, unsigned int in)
+{
+ struct virtio_vsock_pkt *pkt;
+ struct iov_iter iov_iter;
+ size_t nbytes;
+ size_t len;
+
+ if (in != 0) {
+ vq_err(vq, "Expected 0 input buffers, got %u\n", in);
+ return NULL;
+ }
+
+ pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return NULL;
+
+ len = iov_length(vq->iov, out);
+ iov_iter_init(&iov_iter, WRITE, vq->iov, out, len);
+
+ nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter);
+ if (nbytes != sizeof(pkt->hdr)) {
+ vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n",
+ sizeof(pkt->hdr), nbytes);
+ kfree(pkt);
+ return NULL;
+ }
+
+ if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM)
+ pkt->len = le32_to_cpu(pkt->hdr.len);
+
+ /* No payload */
+ if (!pkt->len)
+ return pkt;
+
+ /* The pkt is too big */
+ if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
+ kfree(pkt);
+ return NULL;
+ }
+
+ pkt->buf = kmalloc(pkt->len, GFP_KERNEL);
+ if (!pkt->buf) {
+ kfree(pkt);
+ return NULL;
+ }
+
+ nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter);
+ if (nbytes != pkt->len) {
+ vq_err(vq, "Expected %u byte payload, got %zu bytes\n",
+ pkt->len, nbytes);
+ virtio_transport_free_pkt(pkt);
+ return NULL;
+ }
+
+ return pkt;
+}
+
+static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
+{
+ struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
+ poll.work);
+ struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
+ dev);
+ struct virtio_vsock_pkt *pkt;
+ int head;
+ unsigned int out, in;
+ bool added = false;
+
+ mutex_lock(&vq->mutex);
+ vhost_disable_notify(&vsock->dev, vq);
+ for (;;) {
+ head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
+ &out, &in, NULL, NULL);
+ if (head < 0)
+ break;
+
+ if (head == vq->num) {
+ if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
+ vhost_disable_notify(&vsock->dev, vq);
+ continue;
+ }
+ break;
+ }
+
+ pkt = vhost_vsock_alloc_pkt(vq, out, in);
+ if (!pkt) {
+ vq_err(vq, "Faulted on pkt\n");
+ continue;
+ }
+
+ /* Only accept correctly addressed packets */
+ if (le32_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid)
+ virtio_transport_recv_pkt(pkt);
+ else
+ virtio_transport_free_pkt(pkt);
+
+ vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len);
+ added = true;
+ }
+ if (added)
+ vhost_signal(&vsock->dev, vq);
+ mutex_unlock(&vq->mutex);
+}
+
+static void vhost_vsock_handle_rx_kick(struct vhost_work *work)
+{
+ struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
+ poll.work);
+ struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
+ dev);
+
+ vhost_transport_do_send_pkt(vsock, vq);
+}
+
+static int vhost_vsock_dev_open(struct inode *inode, struct file *file)
+{
+ struct vhost_virtqueue **vqs;
+ struct vhost_vsock *vsock;
+ int ret;
+
+ vsock = kzalloc(sizeof(*vsock), GFP_KERNEL);
+ if (!vsock)
+ return -ENOMEM;
+
+ vqs = kmalloc_array(VSOCK_VQ_MAX, sizeof(*vqs), GFP_KERNEL);
+ if (!vqs) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ vqs[VSOCK_VQ_CTRL] = &vsock->vqs[VSOCK_VQ_CTRL];
+ vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX];
+ vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX];
+ /* The CTRL virtqueue is currently not used so skip it. */
+ vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick;
+ vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick;
+
+ vhost_dev_init(&vsock->dev, vqs, VSOCK_VQ_MAX);
+
+ file->private_data = vsock;
+ init_waitqueue_head(&vsock->send_wait);
+ INIT_LIST_HEAD(&vsock->send_pkt_list);
+ vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work);
+
+ mutex_lock(&vhost_vsock_mutex);
+ list_add_tail(&vsock->list, &vhost_vsock_list);
+ mutex_unlock(&vhost_vsock_mutex);
+ return 0;
+
+out:
+ kfree(vsock);
+ return ret;
+}
+
+static void vhost_vsock_flush(struct vhost_vsock *vsock)
+{
+ int i;
+
+ for (i = 0; i < VSOCK_VQ_MAX; i++)
+ if (vsock->vqs[i].handle_kick)
+ vhost_poll_flush(&vsock->vqs[i].poll);
+ vhost_work_flush(&vsock->dev, &vsock->send_pkt_work);
+}
+
+static int vhost_vsock_dev_release(struct inode *inode, struct file *file)
+{
+ struct vhost_vsock *vsock = file->private_data;
+
+ mutex_lock(&vhost_vsock_mutex);
+ list_del(&vsock->list);
+ mutex_unlock(&vhost_vsock_mutex);
+
+ vhost_dev_stop(&vsock->dev);
+ vhost_vsock_flush(vsock);
+ vhost_dev_cleanup(&vsock->dev, false);
+ kfree(vsock->dev.vqs);
+ kfree(vsock);
+ return 0;
+}
+
+static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u32 guest_cid)
+{
+ struct vhost_vsock *other;
+
+ /* Refuse reserved CIDs */
+ if (guest_cid <= VMADDR_CID_HOST)
+ return -EINVAL;
+
+ /* Refuse if CID is already in use */
+ other = vhost_vsock_get(guest_cid);
+ if (other && other != vsock)
+ return -EADDRINUSE;
+
+ mutex_lock(&vhost_vsock_mutex);
+ vsock->guest_cid = guest_cid;
+ mutex_unlock(&vhost_vsock_mutex);
+
+ return 0;
+}
+
+static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
+{
+ struct vhost_virtqueue *vq;
+ int i;
+
+ if (features & ~VHOST_VSOCK_FEATURES)
+ return -EOPNOTSUPP;
+
+ mutex_lock(&vsock->dev.mutex);
+ if ((features & (1 << VHOST_F_LOG_ALL)) &&
+ !vhost_log_access_ok(&vsock->dev)) {
+ mutex_unlock(&vsock->dev.mutex);
+ return -EFAULT;
+ }
+
+ for (i = 0; i < VSOCK_VQ_MAX; i++) {
+ vq = &vsock->vqs[i];
+ mutex_lock(&vq->mutex);
+ vq->acked_features = features;
+ mutex_unlock(&vq->mutex);
+ }
+ mutex_unlock(&vsock->dev.mutex);
+ return 0;
+}
+
+static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl,
+ unsigned long arg)
+{
+ struct vhost_vsock *vsock = f->private_data;
+ void __user *argp = (void __user *)arg;
+ u64 __user *featurep = argp;
+ u32 __user *cidp = argp;
+ u32 guest_cid;
+ u64 features;
+ int r;
+
+ switch (ioctl) {
+ case VHOST_VSOCK_SET_GUEST_CID:
+ if (get_user(guest_cid, cidp))
+ return -EFAULT;
+ return vhost_vsock_set_cid(vsock, guest_cid);
+ case VHOST_GET_FEATURES:
+ features = VHOST_VSOCK_FEATURES;
+ if (copy_to_user(featurep, &features, sizeof(features)))
+ return -EFAULT;
+ return 0;
+ case VHOST_SET_FEATURES:
+ if (copy_from_user(&features, featurep, sizeof(features)))
+ return -EFAULT;
+ return vhost_vsock_set_features(vsock, features);
+ default:
+ mutex_lock(&vsock->dev.mutex);
+ r = vhost_dev_ioctl(&vsock->dev, ioctl, argp);
+ if (r == -ENOIOCTLCMD)
+ r = vhost_vring_ioctl(&vsock->dev, ioctl, argp);
+ else
+ vhost_vsock_flush(vsock);
+ mutex_unlock(&vsock->dev.mutex);
+ return r;
+ }
+}
+
+static const struct file_operations vhost_vsock_fops = {
+ .owner = THIS_MODULE,
+ .open = vhost_vsock_dev_open,
+ .release = vhost_vsock_dev_release,
+ .llseek = noop_llseek,
+ .unlocked_ioctl = vhost_vsock_dev_ioctl,
+};
+
+static struct miscdevice vhost_vsock_misc = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "vhost-vsock",
+ .fops = &vhost_vsock_fops,
+};
+
+static struct virtio_transport vhost_transport = {
+ .transport = {
+ .get_local_cid = vhost_transport_get_local_cid,
+
+ .init = virtio_transport_do_socket_init,
+ .destruct = virtio_transport_destruct,
+ .release = virtio_transport_release,
+ .connect = virtio_transport_connect,
+ .shutdown = virtio_transport_shutdown,
+
+ .dgram_enqueue = virtio_transport_dgram_enqueue,
+ .dgram_dequeue = virtio_transport_dgram_dequeue,
+ .dgram_bind = virtio_transport_dgram_bind,
+ .dgram_allow = virtio_transport_dgram_allow,
+
+ .stream_enqueue = virtio_transport_stream_enqueue,
+ .stream_dequeue = virtio_transport_stream_dequeue,
+ .stream_has_data = virtio_transport_stream_has_data,
+ .stream_has_space = virtio_transport_stream_has_space,
+ .stream_rcvhiwat = virtio_transport_stream_rcvhiwat,
+ .stream_is_active = virtio_transport_stream_is_active,
+ .stream_allow = virtio_transport_stream_allow,
+
+ .notify_poll_in = virtio_transport_notify_poll_in,
+ .notify_poll_out = virtio_transport_notify_poll_out,
+ .notify_recv_init = virtio_transport_notify_recv_init,
+ .notify_recv_pre_block = virtio_transport_notify_recv_pre_block,
+ .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue,
+ .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
+ .notify_send_init = virtio_transport_notify_send_init,
+ .notify_send_pre_block = virtio_transport_notify_send_pre_block,
+ .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
+ .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
+
+ .set_buffer_size = virtio_transport_set_buffer_size,
+ .set_min_buffer_size = virtio_transport_set_min_buffer_size,
+ .set_max_buffer_size = virtio_transport_set_max_buffer_size,
+ .get_buffer_size = virtio_transport_get_buffer_size,
+ .get_min_buffer_size = virtio_transport_get_min_buffer_size,
+ .get_max_buffer_size = virtio_transport_get_max_buffer_size,
+ },
+
+ .send_pkt = vhost_transport_send_pkt,
+ .send_pkt_no_sock = vhost_transport_send_pkt_no_sock,
+};
+
+static int __init vhost_vsock_init(void)
+{
+ int ret;
+
+ ret = vsock_core_init(&vhost_transport.transport);
+ if (ret < 0)
+ return ret;
+ return misc_register(&vhost_vsock_misc);
+};
+
+static void __exit vhost_vsock_exit(void)
+{
+ misc_deregister(&vhost_vsock_misc);
+ vsock_core_exit();
+};
+
+module_init(vhost_vsock_init);
+module_exit(vhost_vsock_exit);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Asias He");
+MODULE_DESCRIPTION("vhost transport for vsock ");
diff --git a/drivers/vhost/vsock.h b/drivers/vhost/vsock.h
new file mode 100644
index 0000000..0ddb107
--- /dev/null
+++ b/drivers/vhost/vsock.h
@@ -0,0 +1,4 @@
+#ifndef VHOST_VSOCK_H
+#define VHOST_VSOCK_H
+#define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u32)
+#endif
--
2.5.0
^ permalink raw reply related
* [RFC v4 5/5] VSOCK: Add Makefile and Kconfig
From: Stefan Hajnoczi @ 2015-12-22 9:07 UTC (permalink / raw)
To: kvm
Cc: Stefan Hajnoczi, Michael S. Tsirkin, netdev, virtualization,
Matt Benjamin, Asias He, Christoffer Dall, matt.ma
In-Reply-To: <1450775258-18287-1-git-send-email-stefanha@redhat.com>
From: Asias He <asias@redhat.com>
Enable virtio-vsock and vhost-vsock.
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
v4:
* Make checkpatch.pl happy with longer option description
* Clarify dependency on virtio rather than QEMU as suggested by Alex
Bennee
v3:
* Don't put vhost vsock driver into staging
* Add missing Kconfig dependencies (Arnd Bergmann <arnd@arndb.de>)
---
drivers/vhost/Kconfig | 15 +++++++++++++++
drivers/vhost/Makefile | 4 ++++
net/vmw_vsock/Kconfig | 19 +++++++++++++++++++
net/vmw_vsock/Makefile | 2 ++
4 files changed, 40 insertions(+)
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 533eaf0..d7aae9e 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -21,6 +21,21 @@ config VHOST_SCSI
Say M here to enable the vhost_scsi TCM fabric module
for use with virtio-scsi guests
+config VHOST_VSOCK
+ tristate "vhost virtio-vsock driver"
+ depends on VSOCKETS && EVENTFD
+ select VIRTIO_VSOCKETS_COMMON
+ select VHOST
+ select VHOST_RING
+ default n
+ ---help---
+ This kernel module can be loaded in the host kernel to provide AF_VSOCK
+ sockets for communicating with guests. The guests must have the
+ virtio_transport.ko driver loaded to use the virtio-vsock device.
+
+ To compile this driver as a module, choose M here: the module will be called
+ vhost_vsock.
+
config VHOST_RING
tristate
---help---
diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile
index e0441c3..6b012b9 100644
--- a/drivers/vhost/Makefile
+++ b/drivers/vhost/Makefile
@@ -4,5 +4,9 @@ vhost_net-y := net.o
obj-$(CONFIG_VHOST_SCSI) += vhost_scsi.o
vhost_scsi-y := scsi.o
+obj-$(CONFIG_VHOST_VSOCK) += vhost_vsock.o
+vhost_vsock-y := vsock.o
+
obj-$(CONFIG_VHOST_RING) += vringh.o
+
obj-$(CONFIG_VHOST) += vhost.o
diff --git a/net/vmw_vsock/Kconfig b/net/vmw_vsock/Kconfig
index 14810ab..f27e74b 100644
--- a/net/vmw_vsock/Kconfig
+++ b/net/vmw_vsock/Kconfig
@@ -26,3 +26,22 @@ config VMWARE_VMCI_VSOCKETS
To compile this driver as a module, choose M here: the module
will be called vmw_vsock_vmci_transport. If unsure, say N.
+
+config VIRTIO_VSOCKETS
+ tristate "virtio transport for Virtual Sockets"
+ depends on VSOCKETS && VIRTIO
+ select VIRTIO_VSOCKETS_COMMON
+ help
+ This module implements a virtio transport for Virtual Sockets.
+
+ Enable this transport if your Virtual Machine host supports Virtual
+ Sockets over virtio.
+
+ To compile this driver as a module, choose M here: the module
+ will be called virtio_vsock_transport. If unsure, say N.
+
+config VIRTIO_VSOCKETS_COMMON
+ tristate
+ ---help---
+ This option is selected by any driver which needs to access
+ the virtio_vsock.
diff --git a/net/vmw_vsock/Makefile b/net/vmw_vsock/Makefile
index 2ce52d7..cf4c294 100644
--- a/net/vmw_vsock/Makefile
+++ b/net/vmw_vsock/Makefile
@@ -1,5 +1,7 @@
obj-$(CONFIG_VSOCKETS) += vsock.o
obj-$(CONFIG_VMWARE_VMCI_VSOCKETS) += vmw_vsock_vmci_transport.o
+obj-$(CONFIG_VIRTIO_VSOCKETS) += virtio_transport.o
+obj-$(CONFIG_VIRTIO_VSOCKETS_COMMON) += virtio_transport_common.o
vsock-y += af_vsock.o vsock_addr.o
--
2.5.0
^ permalink raw reply related
* [PATCH 1/2] virtio_balloon: fix race by fill and leak
From: Minchan Kim @ 2015-12-27 23:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Rafael Aquini, Michael S. Tsirkin, Minchan Kim, linux-kernel,
stable, virtualization, linux-mm, Konstantin Khlebnikov
During my compaction-related stuff, I encountered a bug
with ballooning.
With repeated inflating and deflating cycle, guest memory(
ie, cat /proc/meminfo | grep MemTotal) is decreased and
couldn't be recovered.
The reason is balloon_lock doesn't cover release_pages_balloon
so struct virtio_balloon fields could be overwritten by race
of fill_balloon(e,g, vb->*pfns could be critical).
This patch fixes it in my test.
Cc: <stable@vger.kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
drivers/virtio/virtio_balloon.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 7efc32945810..7d3e5d0e9aa4 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -209,8 +209,8 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num)
*/
if (vb->num_pfns != 0)
tell_host(vb, vb->deflate_vq);
- mutex_unlock(&vb->balloon_lock);
release_pages_balloon(vb);
+ mutex_unlock(&vb->balloon_lock);
return num_freed_pages;
}
--
1.9.1
^ permalink raw reply related
* [PATCH 2/2] virtio_balloon: fix race between migration and ballooning
From: Minchan Kim @ 2015-12-27 23:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Rafael Aquini, Michael S. Tsirkin, Minchan Kim, linux-kernel,
stable, virtualization, linux-mm, Konstantin Khlebnikov
In-Reply-To: <1451259313-26353-1-git-send-email-minchan@kernel.org>
In balloon_page_dequeue, pages_lock should cover the loop
(ie, list_for_each_entry_safe). Otherwise, the cursor page could
be isolated by compaction and then list_del by isolation could
poison the page->lru.{prev,next} so the loop finally could
access wrong address like this. This patch fixes the bug.
general protection fault: 0000 [#1] SMP
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 2 PID: 82 Comm: vballoon Not tainted 4.4.0-rc5-mm1-access_bit+ #1906
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff8800a7ff0000 ti: ffff8800a7fec000 task.ti: ffff8800a7fec000
RIP: 0010:[<ffffffff8115e754>] [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130
RSP: 0018:ffff8800a7fefdc0 EFLAGS: 00010246
RAX: ffff88013fff9a70 RBX: ffffea000056fe00 RCX: 0000000000002b7d
RDX: ffff88013fff9a70 RSI: ffffea000056fe00 RDI: ffff88013fff9a68
RBP: ffff8800a7fefde8 R08: ffffea000056fda0 R09: 0000000000000000
R10: ffff8800a7fefd90 R11: 0000000000000001 R12: dead0000000000e0
R13: ffffea000056fe20 R14: ffff880138809070 R15: ffff880138809060
FS: 0000000000000000(0000) GS:ffff88013fc40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f229c10e000 CR3: 00000000b8b53000 CR4: 00000000000006a0
Stack:
0000000000000100 ffff880138809088 ffff880138809000 ffff880138809060
0000000000000046 ffff8800a7fefe28 ffffffff812c86d3 ffff880138809020
ffff880138809000 fffffffffff91900 0000000000000100 ffff880138809060
Call Trace:
[<ffffffff812c86d3>] leak_balloon+0x93/0x1a0
[<ffffffff812c8bc7>] balloon+0x217/0x2a0
[<ffffffff8143739e>] ? __schedule+0x31e/0x8b0
[<ffffffff81078160>] ? abort_exclusive_wait+0xb0/0xb0
[<ffffffff812c89b0>] ? update_balloon_stats+0xf0/0xf0
[<ffffffff8105b6e9>] kthread+0xc9/0xe0
[<ffffffff8105b620>] ? kthread_park+0x60/0x60
[<ffffffff8143b4af>] ret_from_fork+0x3f/0x70
[<ffffffff8105b620>] ? kthread_park+0x60/0x60
Code: 8d 60 e0 0f 84 af 00 00 00 48 8b 43 20 a8 01 75 3b 48 89 d8 f0 0f ba 28 00 72 10 48 8b 03 f6 c4 08 75 2f 48 89 df e8 8c 83 f9 ff <49> 8b 44 24 20 4d 8d 6c 24 20 48 83 e8 20 4d 39 f5 74 7a 4c 89
RIP [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130
RSP <ffff8800a7fefdc0>
---[ end trace 43cf28060d708d5f ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Cc: <stable@vger.kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
mm/balloon_compaction.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c
index d3116be5a00f..300117f1a08f 100644
--- a/mm/balloon_compaction.c
+++ b/mm/balloon_compaction.c
@@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
bool dequeued_page;
dequeued_page = false;
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) {
/*
* Block others from accessing the 'page' while we get around
@@ -75,15 +76,14 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
continue;
}
#endif
- spin_lock_irqsave(&b_dev_info->pages_lock, flags);
balloon_page_delete(page);
__count_vm_event(BALLOON_DEFLATE);
- spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
unlock_page(page);
dequeued_page = true;
break;
}
}
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
if (!dequeued_page) {
/*
--
1.9.1
^ permalink raw reply related
* Re: [PATCH 1/2] virtio_balloon: fix race by fill and leak
From: Rafael Aquini @ 2015-12-27 23:36 UTC (permalink / raw)
To: Minchan Kim
Cc: Michael S. Tsirkin, linux-kernel, stable, virtualization,
linux-mm, Andrew Morton, Konstantin Khlebnikov
In-Reply-To: <1451259313-26353-1-git-send-email-minchan@kernel.org>
On Mon, Dec 28, 2015 at 08:35:12AM +0900, Minchan Kim wrote:
> During my compaction-related stuff, I encountered a bug
> with ballooning.
>
> With repeated inflating and deflating cycle, guest memory(
> ie, cat /proc/meminfo | grep MemTotal) is decreased and
> couldn't be recovered.
>
> The reason is balloon_lock doesn't cover release_pages_balloon
> so struct virtio_balloon fields could be overwritten by race
> of fill_balloon(e,g, vb->*pfns could be critical).
>
> This patch fixes it in my test.
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Minchan Kim <minchan@kernel.org>
> ---
> drivers/virtio/virtio_balloon.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 7efc32945810..7d3e5d0e9aa4 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -209,8 +209,8 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num)
> */
> if (vb->num_pfns != 0)
> tell_host(vb, vb->deflate_vq);
> - mutex_unlock(&vb->balloon_lock);
> release_pages_balloon(vb);
> + mutex_unlock(&vb->balloon_lock);
> return num_freed_pages;
> }
>
> --
> 1.9.1
>
Acked-by: Rafael Aquini <aquini@redhat.com>
^ permalink raw reply
* Re: [PATCH 2/2] virtio_balloon: fix race between migration and ballooning
From: Rafael Aquini @ 2015-12-27 23:36 UTC (permalink / raw)
To: Minchan Kim
Cc: Michael S. Tsirkin, linux-kernel, stable, virtualization,
linux-mm, Andrew Morton, Konstantin Khlebnikov
In-Reply-To: <1451259313-26353-2-git-send-email-minchan@kernel.org>
On Mon, Dec 28, 2015 at 08:35:13AM +0900, Minchan Kim wrote:
> In balloon_page_dequeue, pages_lock should cover the loop
> (ie, list_for_each_entry_safe). Otherwise, the cursor page could
> be isolated by compaction and then list_del by isolation could
> poison the page->lru.{prev,next} so the loop finally could
> access wrong address like this. This patch fixes the bug.
>
> general protection fault: 0000 [#1] SMP
> Dumping ftrace buffer:
> (ftrace buffer empty)
> Modules linked in:
> CPU: 2 PID: 82 Comm: vballoon Not tainted 4.4.0-rc5-mm1-access_bit+ #1906
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> task: ffff8800a7ff0000 ti: ffff8800a7fec000 task.ti: ffff8800a7fec000
> RIP: 0010:[<ffffffff8115e754>] [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130
> RSP: 0018:ffff8800a7fefdc0 EFLAGS: 00010246
> RAX: ffff88013fff9a70 RBX: ffffea000056fe00 RCX: 0000000000002b7d
> RDX: ffff88013fff9a70 RSI: ffffea000056fe00 RDI: ffff88013fff9a68
> RBP: ffff8800a7fefde8 R08: ffffea000056fda0 R09: 0000000000000000
> R10: ffff8800a7fefd90 R11: 0000000000000001 R12: dead0000000000e0
> R13: ffffea000056fe20 R14: ffff880138809070 R15: ffff880138809060
> FS: 0000000000000000(0000) GS:ffff88013fc40000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> CR2: 00007f229c10e000 CR3: 00000000b8b53000 CR4: 00000000000006a0
> Stack:
> 0000000000000100 ffff880138809088 ffff880138809000 ffff880138809060
> 0000000000000046 ffff8800a7fefe28 ffffffff812c86d3 ffff880138809020
> ffff880138809000 fffffffffff91900 0000000000000100 ffff880138809060
> Call Trace:
> [<ffffffff812c86d3>] leak_balloon+0x93/0x1a0
> [<ffffffff812c8bc7>] balloon+0x217/0x2a0
> [<ffffffff8143739e>] ? __schedule+0x31e/0x8b0
> [<ffffffff81078160>] ? abort_exclusive_wait+0xb0/0xb0
> [<ffffffff812c89b0>] ? update_balloon_stats+0xf0/0xf0
> [<ffffffff8105b6e9>] kthread+0xc9/0xe0
> [<ffffffff8105b620>] ? kthread_park+0x60/0x60
> [<ffffffff8143b4af>] ret_from_fork+0x3f/0x70
> [<ffffffff8105b620>] ? kthread_park+0x60/0x60
> Code: 8d 60 e0 0f 84 af 00 00 00 48 8b 43 20 a8 01 75 3b 48 89 d8 f0 0f ba 28 00 72 10 48 8b 03 f6 c4 08 75 2f 48 89 df e8 8c 83 f9 ff <49> 8b 44 24 20 4d 8d 6c 24 20 48 83 e8 20 4d 39 f5 74 7a 4c 89
> RIP [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130
> RSP <ffff8800a7fefdc0>
> ---[ end trace 43cf28060d708d5f ]---
> Kernel panic - not syncing: Fatal exception
> Dumping ftrace buffer:
> (ftrace buffer empty)
> Kernel Offset: disabled
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Minchan Kim <minchan@kernel.org>
> ---
> mm/balloon_compaction.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c
> index d3116be5a00f..300117f1a08f 100644
> --- a/mm/balloon_compaction.c
> +++ b/mm/balloon_compaction.c
> @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
> bool dequeued_page;
>
> dequeued_page = false;
> + spin_lock_irqsave(&b_dev_info->pages_lock, flags);
> list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) {
> /*
> * Block others from accessing the 'page' while we get around
> @@ -75,15 +76,14 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
> continue;
> }
> #endif
> - spin_lock_irqsave(&b_dev_info->pages_lock, flags);
> balloon_page_delete(page);
> __count_vm_event(BALLOON_DEFLATE);
> - spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
> unlock_page(page);
> dequeued_page = true;
> break;
> }
> }
> + spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
>
> if (!dequeued_page) {
> /*
> --
> 1.9.1
>
Acked-by: Rafael Aquini <aquini@redhat.com>
^ permalink raw reply
* Re: [PATCH] virtio: make find_vqs() checkpatch.pl-friendly
From: Bjorn Andersson @ 2015-12-28 18:44 UTC (permalink / raw)
To: Stefan Hajnoczi; +Cc: Michael S. Tsirkin, linux-kernel, virtualization
In-Reply-To: <1450342423-18150-1-git-send-email-stefanha@redhat.com>
On Thu 17 Dec 00:53 PST 2015, Stefan Hajnoczi wrote:
> checkpatch.pl wants arrays of strings declared as follows:
>
> static const char * const names[] = { "vq-1", "vq-2", "vq-3" };
>
> Currently the find_vqs() function takes a const char *names[] argument
> so passing checkpatch.pl's const char * const names[] results in a
> compiler error due to losing the second const.
>
> This patch adjusts the find_vqs() prototype and updates all virtio
> transports. This makes it possible for virtio_balloon.c, virtio_input.c,
> virtgpu_kms.c, and virtio_rpmsg_bus.c to use the checkpatch.pl-friendly
> type.
>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Regards,
Bjorn
> ---
> Compile-tested drivers/virtio/ but not the more exotic source files in this
> patch.
>
> drivers/gpu/drm/virtio/virtgpu_kms.c | 2 +-
> drivers/misc/mic/card/mic_virtio.c | 2 +-
> drivers/remoteproc/remoteproc_virtio.c | 2 +-
> drivers/rpmsg/virtio_rpmsg_bus.c | 2 +-
> drivers/s390/virtio/kvm_virtio.c | 2 +-
> drivers/s390/virtio/virtio_ccw.c | 2 +-
> drivers/virtio/virtio_balloon.c | 2 +-
> drivers/virtio/virtio_input.c | 2 +-
> drivers/virtio/virtio_mmio.c | 2 +-
> drivers/virtio/virtio_pci_common.c | 4 ++--
> drivers/virtio/virtio_pci_common.h | 2 +-
> drivers/virtio/virtio_pci_modern.c | 2 +-
> include/linux/virtio_config.h | 2 +-
> 13 files changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c
> index 06496a1..4150873 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_kms.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c
> @@ -130,7 +130,7 @@ int virtio_gpu_driver_load(struct drm_device *dev, unsigned long flags)
> static vq_callback_t *callbacks[] = {
> virtio_gpu_ctrl_ack, virtio_gpu_cursor_ack
> };
> - static const char *names[] = { "control", "cursor" };
> + static const char * const names[] = { "control", "cursor" };
>
> struct virtio_gpu_device *vgdev;
> /* this will expand later */
> diff --git a/drivers/misc/mic/card/mic_virtio.c b/drivers/misc/mic/card/mic_virtio.c
> index e486a0c..f6ed57d 100644
> --- a/drivers/misc/mic/card/mic_virtio.c
> +++ b/drivers/misc/mic/card/mic_virtio.c
> @@ -311,7 +311,7 @@ unmap:
> static int mic_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct mic_vdev *mvdev = to_micvdev(vdev);
> struct mic_device_ctrl __iomem *dc = mvdev->dc;
> diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
> index e1a1023..e44872f 100644
> --- a/drivers/remoteproc/remoteproc_virtio.c
> +++ b/drivers/remoteproc/remoteproc_virtio.c
> @@ -147,7 +147,7 @@ static void rproc_virtio_del_vqs(struct virtio_device *vdev)
> static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct rproc *rproc = vdev_to_rproc(vdev);
> int i, ret;
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index 73354ee..1fcd27c 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -945,7 +945,7 @@ static void rpmsg_ns_cb(struct rpmsg_channel *rpdev, void *data, int len,
> static int rpmsg_probe(struct virtio_device *vdev)
> {
> vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
> - const char *names[] = { "input", "output" };
> + static const char * const names[] = { "input", "output" };
> struct virtqueue *vqs[2];
> struct virtproc_info *vrp;
> void *bufs_va;
> diff --git a/drivers/s390/virtio/kvm_virtio.c b/drivers/s390/virtio/kvm_virtio.c
> index 53fb975..1d060fd 100644
> --- a/drivers/s390/virtio/kvm_virtio.c
> +++ b/drivers/s390/virtio/kvm_virtio.c
> @@ -255,7 +255,7 @@ static void kvm_del_vqs(struct virtio_device *vdev)
> static int kvm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct kvm_device *kdev = to_kvmdev(vdev);
> int i;
> diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
> index b2a1a81..5a433ae 100644
> --- a/drivers/s390/virtio/virtio_ccw.c
> +++ b/drivers/s390/virtio/virtio_ccw.c
> @@ -635,7 +635,7 @@ out:
> static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct virtio_ccw_device *vcdev = to_vc_device(vdev);
> unsigned long *indicatorp = NULL;
> diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
> index 7efc329..d0f0817c 100644
> --- a/drivers/virtio/virtio_balloon.c
> +++ b/drivers/virtio/virtio_balloon.c
> @@ -388,7 +388,7 @@ static int init_vqs(struct virtio_balloon *vb)
> {
> struct virtqueue *vqs[3];
> vq_callback_t *callbacks[] = { balloon_ack, balloon_ack, stats_request };
> - const char *names[] = { "inflate", "deflate", "stats" };
> + static const char * const names[] = { "inflate", "deflate", "stats" };
> int err, nvqs;
>
> /*
> diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
> index c96944b..350a2a5 100644
> --- a/drivers/virtio/virtio_input.c
> +++ b/drivers/virtio/virtio_input.c
> @@ -170,7 +170,7 @@ static int virtinput_init_vqs(struct virtio_input *vi)
> struct virtqueue *vqs[2];
> vq_callback_t *cbs[] = { virtinput_recv_events,
> virtinput_recv_status };
> - static const char *names[] = { "events", "status" };
> + static const char * const names[] = { "events", "status" };
> int err;
>
> err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names);
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index f499d9d..745c6ee 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -482,7 +482,7 @@ error_available:
> static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
> unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
> diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
> index 78f804a..36205c2 100644
> --- a/drivers/virtio/virtio_pci_common.c
> +++ b/drivers/virtio/virtio_pci_common.c
> @@ -296,7 +296,7 @@ void vp_del_vqs(struct virtio_device *vdev)
> static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[],
> + const char * const names[],
> bool use_msix,
> bool per_vq_vectors)
> {
> @@ -376,7 +376,7 @@ error_find:
> int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> int err;
>
> diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
> index b976d96..2cc2522 100644
> --- a/drivers/virtio/virtio_pci_common.h
> +++ b/drivers/virtio/virtio_pci_common.h
> @@ -139,7 +139,7 @@ void vp_del_vqs(struct virtio_device *vdev);
> int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[]);
> + const char * const names[]);
> const char *vp_bus_name(struct virtio_device *vdev);
>
> /* Setup the affinity for a virtqueue:
> diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
> index 8e5cf19..c0c11fa 100644
> --- a/drivers/virtio/virtio_pci_modern.c
> +++ b/drivers/virtio/virtio_pci_modern.c
> @@ -418,7 +418,7 @@ err_new_queue:
> static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[])
> + const char * const names[])
> {
> struct virtio_pci_device *vp_dev = to_vp_device(vdev);
> struct virtqueue *vq;
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index e5ce8ab..6e6cb0c 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -70,7 +70,7 @@ struct virtio_config_ops {
> int (*find_vqs)(struct virtio_device *, unsigned nvqs,
> struct virtqueue *vqs[],
> vq_callback_t *callbacks[],
> - const char *names[]);
> + const char * const names[]);
> void (*del_vqs)(struct virtio_device *);
> u64 (*get_features)(struct virtio_device *vdev);
> int (*finalize_features)(struct virtio_device *vdev);
> --
> 2.5.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply
* [CISTI'2016]: 11ª Conferencia Ibérica de Sistemas y Tecnologías de Información
From: Maria Lemos @ 2015-12-29 14:04 UTC (permalink / raw)
To: virtualization
[-- Attachment #1: Type: text/plain, Size: 6073 bytes --]
---
-------------------------- CISTI'2016 -----------------------------
11ª Conferencia Ibérica de Sistemas y Tecnologías de Información
15 a 18 junio de 2016, Isla Gran Canaria, España
http://www.aisti.eu/cisti2016/
-------------------------------------------------------------------
Nos satisface invitar a la comunidad académica y empresarial a presentar trabajos a la CISTI'2016 (11ª Conferencia Ibérica de Sistemas y Tecnologías de Información), a celebrar en Gran Canaria, España, entre el 15 y 18 de Junio de 2016, enviando artículos científicos originales sobre ideas innovadoras, soluciones desarrolladas que aborden problemas reales, trabajos empíricos, estudios de caso, etc., en el dominio de los sistemas y tecnologías de la información, que se encuadren en las temáticas de la conferencia.
Podrán ser enviados cuatro tipos de artículos:
Artículo (Full Paper): Trabajos concluidos o consolidados sobre I+D encuadrados en una de las temáticas de la conferencia. Estos artículos tendrán un límite máximo de 6 páginas.
Artículo Corto (Short Paper): Trabajos en curso, pero con resultados preliminares relevantes para ser discutidos. Estos artículos tendrán un límite máximo de 4 páginas.
Artículo Póster (Poster Paper): Trabajos iniciados pero con ideas relevantes para ser discutidas. Estos trabajos tendrán un límite máximo de 2 páginas.
Artículo Empresa (Company Paper): Trabajo de las empresas que muestren experiencias prácticas, la I + D, herramientas, etc, encuadrados en algunos de los temas de la conferencia. Estos artículos son resúmenes con un máximo de 2 páginas.
En el texto del artículo para evaluación por la Comisión Científica no deberán incluirse información que posibilite la identificación de los autores. De este modo, sus filiaciones y referencias bibliográficas no deberán aparecer en la versión inicial. Esta información solamente se incluirá en la versión final del artículo.
Los artículos enviados no deben estar publicados ni sobre revisión en ninguna otra conferencia o publicación nacional o internacional.
Todos los artículos deben seguir las normas de formato y estar escritos en portugués, español o inglés.
Todos los artículos serán objeto de “blind review” por lo menos por dos miembros de la Comisión Científica.
Algunos de los artículos (full papers) pueden ser aceptados como artículos cortos (short papers) o artículos póster. Del mismo modo, algunos de los artículos cortos (short papers) pueden ser aceptados como artículos póster. En estos dos casos, los artículos podrán mantener, para su publicación en las actas, el número de páginas iniciales.
Los autores de trabajos aceptados como artículo póster también deben preparar y imprimir un póster para su exhibición en la conferencia. El póster debe tener una orientación vertical y tamaño A1 o A2. La conferencia ofrece sesiones de trabajo para la presentación y discusión oral de pósters, con 5 minutos por póster.
Los autores de artículos (full papers) aceptados dispondrán de 15 minutos para su presentación, más 5 minutos para la discusión. Los autores de artículos cortos (short papers) y de artículos empresa (company papers) aceptados dispondrán de 11 minutos para su presentación, más 4 minutos para la discusión.
TEMÁTICAS
Los artículos enviados deberán encuadrarse en las grandes temáticas propuestas (los tópicos propuestos para cada temática son meramente indicativos con el fin de encuadrar los trabajos, sin pretender ser restrictivos):
A) OMIS - Organizational Models and Information Systems
(Modelos Organizacionales y Sistemas de Información)
B) KMDSS - Knowledge Management and Decision Support Systems
(Gestión de Conocimiento y Sistemas de Apoyo a la Decisión)
C) SSAAT - Software Systems, Architectures, Applications and Tools
(Sistemas, Arquitecturas, Aplicaciones y Herramientas de Software)
D) CNMPS - Computer Networks, Mobility and Pervasive Systems
(Redes de Computadores, Movilidad y Sistemas Ubicuos)
E) HCC - Human Centered Computing
(Informática Centrada em Usuario)
F) HIS - Health Informatics
(Informática en la Salud)
G) ITE - Information Technologies in Education
(Tecnología de la Información en la Educación)
H) AEC – Architecture and Engineering of Construction
(Arquitectura e Ingeniería de la Construcción)
PUBLICACIÓN & INDEXACIÓN
Para garantizar la publicación de un artículo en las actas (artículo, artículo corto, artículo póster o artículo empresa), por lo menos un autor debe inscribirse en la conferencia hasta el 11 de Abril y que el artículo respete el formato sugerido y no exceda el número máximo de páginas previsto. Adicionalmente, los autores de trabajos que reciban recomendaciones de alteración del artículo, deberán seguir las mismas antes del envío de la versión final.
Para cada inscripción no se publica más de un artículo en las actas. Para la publicación de artículos adicionales el autor deberá pagar un suplemento por cada artículo, hasta un máximo de un artículo.
Los artículos (full papers) serán publicados en libro y en CD con ISBN. Los artículos cortos (short papers), los artículos póster y los artículos empresa se publicarán únicamente en CD con ISBN.
Los artículos (full papers) publicados serán enviados a EI, IEEE XPlore, INSPEC, ISI, SCOPUS y Google Scholar. Los artículos cortos (short papers) publicados serán enviados a EI, IEEE XPlore, INSPEC, ISI, SCOPUS y Google Scholar. Los artículos póster y los artículos empresa serán enviados a EBSCO y EI-Compendex.
FECHAS IMPORTANTES
Envío de artículos: 14 de febrero de 2016
Notificación de admisión: 27 de marzo de 2016
Envío de la versión final de los artículos aceptados: 10 de abril de 2016
Pago de la inscripción para garantizar la inclusión del artículo aceptado en las actas de la conferencia: 8 de abril de 2015.
Contamos con usted. Háganos llegar su contribución.
Web de la CISTI'2016: http://www.aisti.eu/cisti2016/
Saludos,
Maria Lemos
AISTI
http://www.aisti.eu/
[-- Attachment #2: Type: text/plain, Size: 183 bytes --]
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply
* [PATCH 00/34] arch: barrier cleanup + __smp_XXX barriers for virt
From: Michael S. Tsirkin @ 2015-12-30 13:24 UTC (permalink / raw)
To: linux-kernel
Cc: linux-arch, Arnd Bergmann, Stefano Stabellini, Peter Zijlstra,
Andrew Cooper, virtualization
This is really trying to cleanup some virt code, as suggested by Peter, who
said
> You could of course go fix that instead of mutilating things into
> sort-of functional state.
This work is needed for virtio, so it's probably easiest to
merge it through my tree - is this fine by everyone?
Arnd, if you agree, could you ack this please?
Note to arch maintainers: please don't cherry-pick patches out of this patchset
as it's been structured in this order to avoid breaking bisect.
Please send acks instead!
Sometimes, virtualization is weird. For example, virtio does this (conceptually):
#ifdef CONFIG_SMP
smp_mb();
#else
mb();
#endif
Similarly, Xen calls mb() when it's not doing any MMIO at all.
Of course it's wrong in the sense that it's suboptimal. What we would really
like is to have, on UP, exactly the same barrier as on SMP. This is because a
UP guest can run on an SMP host.
But Linux doesn't provide this ability: if CONFIG_SMP is not defined is
optimizes most barriers out to a compiler barrier.
Consider for example x86: what we want is xchg (NOT mfence - there's no real IO
going on here - just switching out of the VM - more like a function call
really) but if built without CONFIG_SMP smp_store_mb does not include this.
Virt in general is probably the only use-case, because this really is an
artifact of interfacing with an SMP host while running an UP kernel,
but since we have (at least) two users, it seems to make sense to
put these APIs in a central place.
In fact, smp_ barriers are stubs on !SMP, so they can be defined as follows:
arch/XXX/include/asm/barrier.h:
#define __smp_mb() DOSOMETHING
include/asm-generic/barrier.h:
#ifdef CONFIG_SMP
#define smp_mb() __smp_mb()
#else
#define smp_mb() barrier()
#endif
This has the benefit of cleaning out a bunch of duplicated
ifdefs on a bunch of architectures - this patchset brings
about a net reduction in LOC, compensated for by extra documentation :)
Then virt can use __smp_XXX when talking to an SMP host.
Touching all archs is a tad tedious, but its fairly straight forward.
The rest of the patchset is structured as follows:
-. Patch 1 documents the __smp APIs, and explains why they are
useful for virt
-. Patches 2-7 makes sure barrier.h on ia64, powerpc, s390 and sparc
includes asm-generic/barrier.h: this is safe because code there matches
asm-generic/barrier.h almost verbatim.
Minor code tweaks were required in a couple of places.
Macros duplicated from asm-generic/barrier.h are dropped
in the process.
I compiled these arches before and after the changes,
dumped the .text section (using objdump -O binary) and
made sure that the object code is exactly identical
before and after the change.
-. Patch 8 fixes up smp_store_mb in asm-generic/barrier.h:
it should call smp_mb and not mb. Luckily only used
in core kernel so we know no one misused it for an
MMIO barrier (so far).
This is the only patch that affects code behaviour
outside virt, and that for !SMP only.
Compile-tested on a bunch of architectures (x86
hardware which I have is unaffected by this).
It's very straightforward so I hope it's enough.
Hoping for some acks on this architecture.
-. Patches 9-14 make sure barrier.h on all remaining
architectures includes asm-generic/barrier.h:
after the change in Patch 8, code there matches
asm-generic/barrier.h almost verbatim.
Macros duplicated from asm-generic/barrier.h are dropped
in the process.
After all that preparatory work, we are getting to the actual change.
-. Patches 15 adds generic smp_XXX wrappers in asm-generic
these select __smp_XXX or barrier() depending on CONFIG_SMP
-. Patches 16-28 change all architectures to
define __smp_XXX macros; the generic code in asm-generic/barrier.h
then defines smp_XXX macros
I compiled the affected arches before and after the changes,
dumped the .text section (using objdump -O binary) and
made sure that the object code is exactly identical
before and after the change.
I couldn't fully build sh,tile,xtensa but I did this test
kernel/rcu/tree.o kernel/sched/wait.o and
kernel/futex.o and tested these instead.
Unfortunately, I don't have a metag cross-build toolset ready.
Hoping for some acks on this architecture.
Finally, the following patches put the __smp_XXX APIs to work for virt:
-. Patches 29-31 convert virtio and xen drivers to use the __smp_XXX APIs
xen patches are untested
virtio ones have been tested on x86
-. Patches 33-34 teach virtio to use
__smp_load_acquire/__smp_store_release/__smp_store_mb
This is what started all this work.
tested on x86
The patchset has been in linux-next for a bit, so far without issues.
Michael S. Tsirkin (34):
Documentation/memory-barriers.txt: document __smb_mb()
asm-generic: guard smp_store_release/load_acquire
ia64: rename nop->iosapic_nop
ia64: reuse asm-generic/barrier.h
powerpc: reuse asm-generic/barrier.h
s390: reuse asm-generic/barrier.h
sparc: reuse asm-generic/barrier.h
asm-generic: smp_store_mb should use smp_mb
arm: reuse asm-generic/barrier.h
arm64: reuse asm-generic/barrier.h
metag: reuse asm-generic/barrier.h
mips: reuse asm-generic/barrier.h
x86/um: reuse asm-generic/barrier.h
x86: reuse asm-generic/barrier.h
asm-generic: add __smp_XXX wrappers
powerpc: define __smp_XXX
arm64: define __smp_XXX
arm: define __smp_XXX
blackfin: define __smp_XXX
ia64: define __smp_XXX
metag: define __smp_XXX
mips: define __smp_XXX
s390: define __smp_XXX
sh: define __smp_XXX, fix smp_store_mb for !SMP
sparc: define __smp_XXX
tile: define __smp_XXX
xtensa: define __smp_XXX
x86: define __smp_XXX
Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb"
virtio_ring: update weak barriers to use __smp_XXX
xenbus: use __smp_XXX barriers
xen/io: use __smp_XXX barriers
virtio: use __smp_load_acquire/__smp_store_release
virtio_ring: use __smp_store_mb
arch/arm/include/asm/barrier.h | 35 ++------------
arch/arm64/include/asm/barrier.h | 19 +++-----
arch/blackfin/include/asm/barrier.h | 4 +-
arch/ia64/include/asm/barrier.h | 24 +++-------
arch/metag/include/asm/barrier.h | 55 +++++++--------------
arch/mips/include/asm/barrier.h | 51 +++++++-------------
arch/powerpc/include/asm/barrier.h | 33 ++++---------
arch/s390/include/asm/barrier.h | 25 +++++-----
arch/sh/include/asm/barrier.h | 3 +-
arch/sparc/include/asm/barrier_32.h | 1 -
arch/sparc/include/asm/barrier_64.h | 29 +++--------
arch/sparc/include/asm/processor.h | 3 --
arch/tile/include/asm/barrier.h | 9 ++--
arch/x86/include/asm/barrier.h | 36 ++++++--------
arch/x86/um/asm/barrier.h | 9 +---
arch/xtensa/include/asm/barrier.h | 4 +-
include/asm-generic/barrier.h | 95 +++++++++++++++++++++++++++++++++----
include/linux/virtio_ring.h | 48 ++++++++++++++++---
include/xen/interface/io/ring.h | 16 +++----
arch/ia64/kernel/iosapic.c | 6 +--
drivers/virtio/virtio_ring.c | 35 +++++++-------
drivers/xen/xenbus/xenbus_comms.c | 8 ++--
Documentation/memory-barriers.txt | 33 +++++++++++--
23 files changed, 292 insertions(+), 289 deletions(-)
--
MST
^ permalink raw reply
* [PATCH 01/34] Documentation/memory-barriers.txt: document __smb_mb()
From: Michael S. Tsirkin @ 2015-12-30 13:24 UTC (permalink / raw)
To: linux-kernel
Cc: linux-arch, Arnd Bergmann, Stefano Stabellini, Peter Zijlstra,
Andrew Cooper, Jonathan Corbet, linux-doc, virtualization
In-Reply-To: <1451473761-30019-1-git-send-email-mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
Documentation/memory-barriers.txt | 33 ++++++++++++++++++++++++++++-----
1 file changed, 28 insertions(+), 5 deletions(-)
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index aef9487..a20f7ef 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -1655,17 +1655,18 @@ macro is a good place to start looking.
SMP memory barriers are reduced to compiler barriers on uniprocessor compiled
systems because it is assumed that a CPU will appear to be self-consistent,
and will order overlapping accesses correctly with respect to itself.
+However, see the subsection on "Virtual Machine Guests" below.
[!] Note that SMP memory barriers _must_ be used to control the ordering of
references to shared memory on SMP systems, though the use of locking instead
is sufficient.
Mandatory barriers should not be used to control SMP effects, since mandatory
-barriers unnecessarily impose overhead on UP systems. They may, however, be
-used to control MMIO effects on accesses through relaxed memory I/O windows.
-These are required even on non-SMP systems as they affect the order in which
-memory operations appear to a device by prohibiting both the compiler and the
-CPU from reordering them.
+barriers impose unnecessary overhead on both SMP and UP systems. They may,
+however, be used to control MMIO effects on accesses through relaxed memory I/O
+windows. These barriers are required even on non-SMP systems as they affect
+the order in which memory operations appear to a device by prohibiting both the
+compiler and the CPU from reordering them.
There are some more advanced barrier functions:
@@ -2948,6 +2949,28 @@ The Alpha defines the Linux kernel's memory barrier model.
See the subsection on "Cache Coherency" above.
+VIRTUAL MACHINE GUESTS
+-------------------
+
+Guests running within virtual machines might be affected by
+SMP effects even if the guest itself is compiled within
+SMP support.
+
+This is an artifact of interfacing with an SMP host while
+running an UP kernel.
+
+Using mandatory barriers for this use-case would be possible
+but is often suboptimal.
+
+To handle this case optimally, low-level __smp_mb() etc macros are available.
+These have the same effect as smp_mb() etc when SMP is enabled, but generate
+identical code for SMP and non-SMP systems. For example, virtual machine guests
+should use __smp_mb() rather than smp_mb() when synchronizing against a
+(possibly SMP) host.
+
+These are equivalent to smp_mb() etc counterparts in all other respects,
+in particular, they do not control MMIO effects: to control
+MMIO effects, use mandatory barriers.
============
EXAMPLE USES
--
MST
^ permalink raw reply related
* [PATCH 02/34] asm-generic: guard smp_store_release/load_acquire
From: Michael S. Tsirkin @ 2015-12-30 13:24 UTC (permalink / raw)
To: linux-kernel
Cc: linux-arch, Arnd Bergmann, Stefano Stabellini, Peter Zijlstra,
Andrew Cooper, virtualization
In-Reply-To: <1451473761-30019-1-git-send-email-mst@redhat.com>
Allow architectures to override smp_store_release
and smp_load_acquire by guarding the defines
in asm-generic/barrier.h with ifndef directives.
This is in preparation to reusing asm-generic/barrier.h
on architectures which have their own definition
of these macros.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
include/asm-generic/barrier.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index b42afad..538f8d1 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -104,13 +104,16 @@
#define smp_mb__after_atomic() smp_mb()
#endif
+#ifndef smp_store_release
#define smp_store_release(p, v) \
do { \
compiletime_assert_atomic_type(*p); \
smp_mb(); \
WRITE_ONCE(*p, v); \
} while (0)
+#endif
+#ifndef smp_load_acquire
#define smp_load_acquire(p) \
({ \
typeof(*p) ___p1 = READ_ONCE(*p); \
@@ -118,6 +121,7 @@ do { \
smp_mb(); \
___p1; \
})
+#endif
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_GENERIC_BARRIER_H */
--
MST
^ permalink raw reply related
* [PATCH 03/34] ia64: rename nop->iosapic_nop
From: Michael S. Tsirkin @ 2015-12-30 13:24 UTC (permalink / raw)
To: linux-kernel
Cc: linux-arch, Fenghua Yu, Tony Luck, linux-ia64, Arnd Bergmann,
Stefano Stabellini, Peter Zijlstra, Andrew Cooper, virtualization,
Thomas Gleixner, Jiang Liu
In-Reply-To: <1451473761-30019-1-git-send-email-mst@redhat.com>
asm-generic/barrier.h defines a nop() macro.
To be able to use this header on ia64, we shouldn't
call local functions/variables nop().
There's one instance where this breaks on ia64:
rename the function to iosapic_nop to avoid the conflict.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
arch/ia64/kernel/iosapic.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index d2fae05..90fde5b 100644
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -256,7 +256,7 @@ set_rte (unsigned int gsi, unsigned int irq, unsigned int dest, int mask)
}
static void
-nop (struct irq_data *data)
+iosapic_nop (struct irq_data *data)
{
/* do nothing... */
}
@@ -415,7 +415,7 @@ iosapic_unmask_level_irq (struct irq_data *data)
#define iosapic_shutdown_level_irq mask_irq
#define iosapic_enable_level_irq unmask_irq
#define iosapic_disable_level_irq mask_irq
-#define iosapic_ack_level_irq nop
+#define iosapic_ack_level_irq iosapic_nop
static struct irq_chip irq_type_iosapic_level = {
.name = "IO-SAPIC-level",
@@ -453,7 +453,7 @@ iosapic_ack_edge_irq (struct irq_data *data)
}
#define iosapic_enable_edge_irq unmask_irq
-#define iosapic_disable_edge_irq nop
+#define iosapic_disable_edge_irq iosapic_nop
static struct irq_chip irq_type_iosapic_edge = {
.name = "IO-SAPIC-edge",
--
MST
^ permalink raw reply related
* [PATCH 04/34] ia64: reuse asm-generic/barrier.h
From: Michael S. Tsirkin @ 2015-12-30 13:24 UTC (permalink / raw)
To: linux-kernel
Cc: linux-arch, Fenghua Yu, Tony Luck, linux-ia64, Arnd Bergmann,
Stefano Stabellini, Peter Zijlstra, Andrew Cooper,
Andrey Konovalov, virtualization, Michael Ellerman, Ingo Molnar
In-Reply-To: <1451473761-30019-1-git-send-email-mst@redhat.com>
On ia64 smp_rmb, smp_wmb, read_barrier_depends, smp_read_barrier_depends
and smp_store_mb() match the asm-generic variants exactly. Drop the
local definitions and pull in asm-generic/barrier.h instead.
This is in preparation to refactoring this code area.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
arch/ia64/include/asm/barrier.h | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/arch/ia64/include/asm/barrier.h b/arch/ia64/include/asm/barrier.h
index df896a1..2f93348 100644
--- a/arch/ia64/include/asm/barrier.h
+++ b/arch/ia64/include/asm/barrier.h
@@ -48,12 +48,6 @@
# define smp_mb() barrier()
#endif
-#define smp_rmb() smp_mb()
-#define smp_wmb() smp_mb()
-
-#define read_barrier_depends() do { } while (0)
-#define smp_read_barrier_depends() do { } while (0)
-
#define smp_mb__before_atomic() barrier()
#define smp_mb__after_atomic() barrier()
@@ -77,12 +71,12 @@ do { \
___p1; \
})
-#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0)
-
/*
* The group barrier in front of the rsm & ssm are necessary to ensure
* that none of the previous instructions in the same group are
* affected by the rsm/ssm.
*/
+#include <asm-generic/barrier.h>
+
#endif /* _ASM_IA64_BARRIER_H */
--
MST
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