After the packet is successfully sent, we should not touch the packet
as it may have been freed. This patch is based on the work done by
Long Li <longli@microsoft.com>.
David, please queue this up for stable.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the packet is successfully sent, we should not touch the skb
as it may have been freed. This patch is based on the work done by
Long Li <longli@microsoft.com>.
In this version of the patch I have fixed issues pointed out by David.
David, please queue this up for stable.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Long Li <longli@microsoft.com>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In win8 we have a feature that allows for interrupt driven flow management
for host/guest communication. For instance, if the host were blocked because
there was no space available in the ringbuffer, the host could request that the
guest send an interrupt when space becomes available in the ringbuffer (when
the guest drains the ringbuffer).
While this feature was implemented in the guest a while ago, we had not
advertised that the guest supported this feature. This patch advertises
the support to the host.
For pre-win8 hosts, this has no effect since the size of the ringbuffer
control structure has not changed and all changes have been backward
compatible - unused/reserved space has been used to implement this
feature.
In this version of the patch I have cleaned up the commit log based on
feedback from Greg KH.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Disable preemption when sampling current processor ID when preemption
is otherwise possible.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Minimize failures in this function by pre-allocating the buffer
for posting messages. The hypercall for posting the message can fail
for a number of reasons:
1. Transient resource related issues
2. Buffer alignment
3. Buffer cannot span a page boundry
We address issues 2 and 3 by preallocating a per-cpu page for the buffer.
Transient resource related failures are handled by retrying by the callers
of this function.
This patch is based on the investigation
done by Dexuan Cui <decui@microsoft.com>.
I would like to thank Sitsofe Wheeler <sitsofe@yahoo.com>
for reporting the issue and helping in debuggging.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate calls to BUG_ON() in vmbus_close_internal().
We have chosen to potentially leak memory, than crash the guest
in case of failures.
In this version of the patch I have addressed comments from
Dan Carpenter (dan.carpenter@oracle.com).
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate the call to BUG_ON() by waiting for the host to respond. We are
trying to reclaim the ownership of memory that was given to the host and so
we will have to wait until the host responds.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Eliminate calls to BUG_ON() by properly handling errors. In cases where
rollback is possible, we will return the appropriate error to have the
calling code decide how to rollback state. In the case where we are
transferring ownership of the guest physical pages to the host,
we will wait for the host to respond.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Posting messages to the host can fail because of transient resource
related failures. Correctly deal with these failures and increase the
number of attempts to post the message before giving up.
In this version of the patch, I have normalized the error code to
Linux error code.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get rid of the warning messages since they will clutter up various system logs
and are of questionable value to the end user. For debugging purposes, this
information can be gotten by setting the scsi log level appropriately.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
WS2008R2 is a supported platform and it turns out that the maximum sendbuf
size that ws2008R2 can support is only 15MB. Make the necessary
adjustment.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Intel did some benchmarking on our network throughput when Linux on Hyper-V
is as used as a gateway. This fix gave us almost a 1 Gbps additional throughput
on about 5Gbps base throughput we hadi, prior to increasing the sendbuf size.
The sendbuf mechanism is a copy based transport that we have which is clearly
more optimal than the copy-free page flipping mechanism (for small packets).
In the forwarding scenario, we deal only with MTU sized packets,
and increasing the size of the senbuf area gave us the additional performance.
For what it is worth, Windows guests on Hyper-V, I am told use similar sendbuf
size as well.
The exact value of sendbuf I think is less important than the fact that it needs
to be larger than what Linux can allocate as physically contiguous memory.
Thus the change over to allocating via vmalloc().
We currently allocate 16MB receive buffer and we use vmalloc there for allocation.
Also the low level channel code has already been modified to deal with physically
dis-contiguous memory in the ringbuffer setup.
Based on experimentation Intel did, they say there was some improvement in throughput
as the sendbuf size was increased up to 16MB and there was no effect on throughput
beyond 16MB. Thus I have chosen 16MB here.
Increasing the sendbuf value makes a material difference in small packet handling
In this version of the patch, based on David's feedback, I have added
additional details in the commit log.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add blist flags to permit the reading of the VPD pages even when
the target may claim SPC-2 compliance. MSFT targets currently
claim SPC-2 compliance while they implement post SPC-2 features.
With this patch we can correctly handle WRITE_SAME_16 issues.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
On some Windows hosts on FC SANs, TEST_UNIT_READY can return SRB_STATUS_ERROR.
Correctly handle this. Note that there is sufficient sense information to
support scsi error handling even in this case.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Correctly set SRB flags for all valid I/O directions. Some IHV drivers on the
Windows host require this. The host validates the command and SRB flags
prior to passing the command down to native driver stack.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
On Azure, we have seen instances of unbounded I/O latencies. To deal with
this issue, implement handler that can reset the timeout. Note that the
host gaurantees that it will respond to each command that has been issued.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
[hch: added a better comment explaining the issue]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Based on the negotiated VMBUS protocol version, we adjust the size of the storage
protocol messages. The two sizes we currently handle are pre-win8 and post-win8.
In WS2012 R2, we are negotiating higher VMBUS protocol version than the win8
version. Make adjustments to correctly handle this.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Going forward it is possible that some of the commands that are not currently
implemented will be implemented on future Windows hosts. Even if they are not
implemented, we are told the host will corrrectly handle unsupported
commands (by returning appropriate return code and sense information).
Make command filtering depend on the host version.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Hyper-V hosts can support multiple targets and multiple channels and larger number of
LUNs per target. Update the code to reflect this. With this patch we can correctly
enumerate all the paths in a multi-path storage environment.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit ID: 7e660100d8 added code to derive the
FLUSH_TIMEOUT from the basic I/O timeout. However, this patch did not use the
basic I/O timeout of the device. Fix this bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add code to poll the channel since we process only one message
at a time and the host may not interrupt us. Also increase the
receive buffer size since some KVP messages are close to 8K bytes in size.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting with Win8, we have implemented several optimizations to improve the
scalability and performance of the VMBUS transport between the Host and the
Guest. Some of the non-performance critical services cannot leverage these
optimization since they only read and process one message at a time.
Make adjustments to the callback dispatch code to account for the way
non-performance critical drivers handle reading of the channel.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current code posts periodic memory pressure status from a dedicated thread.
Under some conditions, especially when we are releasing a lot of memory into
the guest, we may not send timely pressure reports back to the host. Fix this
issue by reporting pressure in all contexts that can be active in this driver.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the mapping of the relID to channel is done under the protection of a
single spin lock. Starting with ws2012, each channel is bound to a specific VCPU
in the guest. Use this binding to eliminate the spin lock by setting up
per-cpu state for mapping relId to the channel.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By ensuring that we set the callback handler to NULL in the channel close
path on the same CPU that the channel is bound to, we can eliminate this lock
acquisition and release in a performance critical path.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do checksum offload only if the client of the driver wants checksum to be
offloaded.
In V1 version of this patch, I addressed comments from
Stephen Hemminger <stephen@networkplumber.org> and
Eric Dumazet <eric.dumazet@gmail.com>.
In this version of the patch I have addressed comments from
David Miller.
This patch fixes a bug that is exposed in gateway scenarios.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We send packets using a copy-free mechanism (this is the Guest to Host transport
via VMBUS). While this is obviously optimal for large packets,
it may not be optimal for small packets. Hyper-V host supports
a second mechanism for sending packets that is "copy based". We implement that
mechanism in this patch.
In this version of the patch I have addressed a comment from David Miller.
With this patch (and all of the other offload and VRSS patches), we are now able
to almost saturate a 10G interface between Linux VMs on Hyper-V
on different hosts - close to 9 Gbps as measured via iperf.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only ws2012r2 hosts support the ability to reconnect to the host on VMBUS. This functionality
is needed by kexec in Linux. To use this functionality we need to negotiate version 3.0 of the
VMBUS protocol.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org> [3.9+]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Return the appropriate error code and handle the case when the target
file exists correctly. This fixes a bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org> [3.14]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The legacy PIC may or may not be available and we need a mechanism to
detect the existence of the legacy PIC that is applicable for all
hardware (both physical as well as virtual) currently supported by
Linux.
On Hyper-V, when our legacy firmware presented to the guests, emulates
the legacy PIC while when our EFI based firmware is presented we do
not emulate the PIC. To support Hyper-V EFI firmware, we had to set
the legacy_pic to the null_legacy_pic since we had to bypass PIC based
calibration in the early boot code. While, on the EFI firmware, we
know we don't emulate the legacy PIC, we need a generic mechanism to
detect the presence of the legacy PIC that is not based on boot time
state - this became apparent when we tried to get kexec to work on
Hyper-V EFI firmware.
This patch implements the proposal put forth by H. Peter Anvin
<hpa@linux.intel.com>: Write a known value to the PIC data port and
read it back. If the value read is the value written, we do have the
PIC, if not there is no PIC and we can safely set the legacy_pic to
null_legacy_pic. Since the read from an unconnected I/O port returns
0xff, we will use ~(1 << PIC_CASCADE_IR) (0xfb: mask all lines except
the cascade line) to probe for the existence of the PIC.
In version V1 of the patch, I had cleaned up the code based on comments from Peter.
In version V2 of the patch, I have addressed additional comments from Peter.
In version V3 of the patch, I have addressed Jan's comments (JBeulich@suse.com).
In version V4 of the patch, I have addressed additional comments from Peter.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1397501029-29286-1-git-send-email-kys@microsoft.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
ws2008r2 does not support UDP checksum offload. Thus, we cannnot turn on
UDP offload in the host. Also, on ws2012 and ws2012 r2, there appear to be
an issue with UDP checksum offload.
Fix this issue by computing the UDP checksum in the Hyper-V driver.
Based on Dave Miller's comments, in this version, I have COWed the skb
before modifying the UDP header (the checksum field).
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ws2008R2 supports ndis_version 6.1 and 6.1 is the minimal version required
for various offloads. Negotiate ndis_version 6.1 when on ws2008r2.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An outgoing packet can potentially need per-packet information for
all the offloads and VLAN tagging. Fix this issue.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 3c86726cfe ("HID: make .raw_request mandatory") made .raw_request
mandatory and broke the Hyper-V mouse driver. This patch fixes the problem.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Increase the number of PFNs we can handle in a single vmbus packet.
Some network packets may have more PFNs than the current limit we have.
This is not a bug and this patch can be applied to the *next tree.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the file copy service for Linux guests on Hyper-V. This permits the
host to copy a file (over VMBUS) into the guest. This facility is part of
"guest integration services" supported on the Windows platform.
Here is a link that provides additional details on this functionality:
http://technet.microsoft.com/en-us/library/dn464282.aspx
In V1 version of the patch I have addressed comments from
Olaf Hering <olaf@aepfle.de> and Dan Carpenter <dan.carpenter@oracle.com>
In V2 version of this patch I did some minor cleanup (making some globals
static). In V4 version of the patch I have addressed all of Olaf's
most recent set of comments/concerns.
In V5 version of the patch I had addressed Greg's most recent comments.
I would like to thank Greg for suggesting that I use misc device; it has
significantly simplified the code.
In V6 version of the patch I have cleaned up error message based on Olaf's
comments. I have also rebased the patch based on the current tip.
In this version of the patch, I have addressed the latest comments from Greg.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get rid of the buffer allocation in the receive path for normal packets.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the receive path a little more efficient by parameterizing the
required state rather than re-establishing that state.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This structure is redundant; get rid of it make the code little more efficient -
get rid of the unnecessary indirection.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The non-interruptible sleep of the memory pressure posting thread
results in higher reported load average. Make this sleep interruptible.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the guest has a FAT file system mounted, skip it during the FREEZE
operation. With this change we can support host initiated backup of
the guest even when the guest may have FAT file systems mounted.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As we implement Virtual Receive Side Scaling on the networking side
(the VRSS patches are currently under review), it will be useful to have
per-channel state that vmbus drivers can manage. Add support for
managing per-channel state.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current channel code is using scatterlist abstraction to pass data to the
ringbuffer API on the send path. This causes unnecessary translations
between virtual and physical addresses. Fix this.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Gen2 firmware, Hyper-V does not emulate the PCI bus. However, the MMIO
information is packaged up in DSDT. Extract this information and export it
for use by the synthetic framebuffer driver. This is the only driver that
needs this currently.
In this version of the patch mmio, I have updated the hyperv header file
(linux/hyperv.h) with mmio definitions.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the guest attempts to connect with the host when there may already be a
connection with the host (as would be the case during the kdump/kexec path),
it is difficult to guarantee timely response from the host. Starting with
WS2012 R2, the host supports this ability to re-connect with the host
(explicitly to support kexec). Prior to responding to the guest, the host
needs to ensure that device states based on the previous connection to
the host have been properly torn down. This may introduce unbounded delays.
To deal with this issue, don't do a timed wait during the initial connect
with the host.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During the initial VMBUS connect phase, starting with WS2012 R2, we should
specify the VPCU in the guest that should receive the notification. Fix this
issue. This fix is required to properly connect to the host in the kexeced
kernel.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org> [3.9+]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pass through the 0xE1 prefix so atkbd can properly parse the scancode
data.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Hyper-V supports a mechanism for retrieving the local APIC frequency.
Use this and bypass the calibration code in the kernel . This would
allow us to boot the Linux kernel as a "modern VM" on Hyper-V where
many of the legacy devices (such as PIT) are not emulated.
I would like to thank Olaf Hering <olaf@aepfle.de>, Jan Beulich <JBeulich@suse.com> and
H. Peter Anvin <h.peter.anvin@intel.com> for their help in this effort.
In this version of the patch, I have addressed Jan's comments.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1380554932-9888-1-git-send-email-olaf@aepfle.de
Tested-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
commit 666b9adc80 terminated vmbus
version negotiation incorrectly. We need to terminate the version
negotiation only if the current negotiation were to timeout.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Olaf Hering <ohering@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current code does not correctly negotiate the version numbers for the util
driver when hosted on earlier hosts. The version numbers presented by this
driver were not compatible with the version numbers supported by Windows Server
2008. Fix this problem.
I would like to thank Olaf Hering (ohering@suse.com) for identifying the problem.
Reported-by: Olaf Hering <ohering@suse.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new driver to support synthetic keyboard. On the next generation
Hyper-V guest firmware, many legacy devices will not be emulated and this
driver will be required.
I would like to thank Vojtech Pavlik <vojtech@suse.cz> for helping me with the
details of the AT keyboard driver. I would also like to thank
Dan Carpenter <dan.carpenter@oracle.com> and
Dmitry Torokhov <dmitry.torokhov@gmail.com> for their detailed review of this
driver.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The current code would attempt to negotiate a different protocol version if
the current negotiation timed out. This triggers an assert in the host (on debug
builds). Avoid this by negotiating a newer version only if the host properly
rejects the current version being negotiated.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The channel state should be correctly set before registering the device. In the current
code the driver probe would fail for channels that have been rescinded and subsequently
re-offered. Fix the bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: stable <stable@vger.kernel.org> # 3.11
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Each message sent from the guest carries with it a transaction ID.
Assign the transaction ID just before putting the message on the VMBUS.
This would help in debugging on the host side.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current code picked the highest version advertised by the host. WS2012 R2
has implemented a protocol version for KVP that is not compatible with prior
protocol versions of KVP. Fix the bug in the current code by explicitly specifying
the protocol version that the guest can support.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we are posting pressure status, we may get interrupted and handle
the un-balloon operation. In this case just don't post the status as we
know the pressure status is stale.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As we hot-add 128 MB chunks of memory, we wait to ensure that the memory
is onlined before attempting to hot-add the next chunk. If the udev rule for
memory hot-add is not executed within the allowed time, we would rollback the
state and abort further hot-add. Since the hot-add has succeeded and the only
failure is that the memory is not onlined within the allowed time, we should not
be rolling back the state. Fix this bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Increase the value of STORVSC_MAX_IO_REQUESTS to 200 requests. The current
ringbuffer size can support this higher value.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
The standard scsi timeout is not appropriate in some of the environments where
Hyper-V is deployed. Set this timeout appropriately for all devices managed
by this driver.
On cloud environments where storage latencies may be unbounded, having the
scsi layer initiating recovery can be problematic since (a) the host is
already implementing a variety of recovery strategies and (b) implementing a
recovery strategy at the VM level may be more appropriate in cases where
storage latencies exceed a certain threshold.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Starting with Win8, the host supports multiple sub-channels for a given
device. As in the past, the initial channel offer specifies the device and
is associated with both the type and the instance GUIDs. For performance
critical devices, the host may support multiple sub-channels. The sub-channels
share the same type and instance GUID as the primary channel. The number of
sub-channels offerrred to the guest depends on the number of virtual CPUs
assigned to the guest. The guest can request the creation of these sub-channels
and once created and opened, the guest can distribute the traffic across all
the channels (the primary and the sub-channels). A request sent on a sub-channel
will have the response delivered on the same sub-channel.
At channel (sub-channel) creation we bind the channel interrupt to a CPU and
with this sub-channel support we will be able to spread the interrupt load
of a given device across all available CPUs.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux' notion of cpuid is different from the Host's notion of CPUID. In the
call to bind the channel interrupts, we should use the host's notion of
CPU Ids. Fix this bug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org> (V3.9)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As part of updating the vmbus protocol, the function hv_need_to_signal()
was introduced. This functions helps optimize signalling from guest to
host. The newly added memory barrier is needed to ensure that we correctly
decide when to signal the host.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reported-by: Olaf Hering <olh@suse.de>
Cc: Stable <stable@vger.kernel.org> (V3.8+)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If memory hot-add fails with the error -EEXIST, then this is a permanent
failure. Notify the host of this information, so the host will not attempt
hot-add again. If the failure were a transient failure, host will attempt
a hot-add after some delay.
In this version of the patch, I have added some additional comments
to clarify how the host treats different failure conditions.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Hyper-V it will be very efficient to use 2M allocations in the guest as this
makes the ballooning protocol with the host that much more efficient. Hyper-V
uses page ranges (start pfn : number of pages) to specify memory being moved
around and with 2M pages this encoding can be very efficient. However, when
memory is returned to the guest, the host does not guarantee any granularity.
To deal with this issue, split the page soon after a successful 2M allocation
so that this memory can potentially be freed as 4K pages.
If 2M allocations fail, we revert to 4K allocations.
In this version of the patch, based on the feedback from Michal Hocko
<mhocko@suse.cz>, I have added some additional commentary to the patch
description.
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some Windows hosts permit the guest to specify memory hot-add alignment
requirements (if any). Linux currently requires a 128MB alignment on memory
segments that can be hot-added. Specify this alignment requirement to the
host.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver supports host initiated backup of the guest. On Windows guests,
the host can generate application consistent backups using the Windows VSS
framework. On Linux, we ensure that the backup will be file system consistent.
This driver allows the host to initiate a "Freeze" operation on all the mounted
file systems in the guest. Once the mounted file systems in the guest are frozen,
the host snapshots the guest's file systems. Once this is done, the guest's file
systems are "thawed".
This driver has a user-level component (daemon) that invokes the appropriate
operation on all the mounted file systems in response to the requests from
the host. The duration for which the guest is frozen is very short - a few seconds.
During this interval, the diff disk is comitted.
In this version of the patch I have addressed the feedback from Olaf Herring.
Also, some of the connector related issues have been fixed.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Properly cleanup the channel state on receipt of the "offer rescind" message.
Starting with ws2012, the host requires that the channel "relid" be properly
cleaned up when the offer is rescinded.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Implement the memory hot-add functionality. With this, Linux guests can fully
participate in the Dynamic Memory protocol implemented in the Windows hosts.
In this version of the patch, based Olaf Herring's feedback, I have gotten
rid of the module level dependency on MEMORY_HOTPLUG. Instead the code within
the driver that depends on MEMORY_HOTPLUG has the appropriate compilation
switches. This would allow this driver to support pure ballooning in cases
where the kernel does not support memory hotplug.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The balloon driver is stateful. For instance, it needs to keep track of pages
that have been ballooned out to properly post pressure reports. This state cannot
be re-constructed if the driver were to be unloaded and subsequently loaded.
Furthermore, as we support memory hot-add as part of this driver, this driver becomes
even more stateful and this state cannot be re-created. Make the balloon driver
unloadable to deal with this issue.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Execute the hot-add operation in a separate work context.
This allows us to decouple the pressure reporting activity from the
"hot-add" activity. Testing has shown that this makes the guest more
responsive to hot add requests.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Execute the balloon inflation operation in a separate work context.
This allows us to decouple the pressure reporting activity from the
ballooning activity. Testing has shown that this decoupling makes the
guest more reponsive.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to request completion notification; get rid of it.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the infrastructure for delivering VMBUS interrupts using a
special vector. With this patch, we can now properly handle
the VMBUS interrupts that can be delivered on any CPU. Also,
turn on interrupt load balancing as well.
This patch requires the infrastructure that was implemented in the patch:
X86: Handle Hyper-V vmbus interrupts as special hypervisor interrupts
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation for handling additional sense codes, restructure and cleanup
the error handling code in the command completion code path.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Starting with win8, vmbus interrupts can be delivered on any VCPU in the guest
and furthermore can be concurrently active on multiple VCPUs. Support this
interrupt delivery model by setting up a separate IDT entry for Hyper-V vmbus.
interrupts. I would like to thank Jan Beulich <JBeulich@suse.com> and
Thomas Gleixner <tglx@linutronix.de>, for their help.
In this version of the patch, based on the feedback, I have merged the IDT
vector for Xen and Hyper-V and made the necessary adjustments. Furhermore,
based on Jan's feedback I have added the necessary compilation switches.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1359940959-32168-3-git-send-email-kys@microsoft.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Xen emulates Hyper-V to host enlightened Windows. Looks like this
emulation may be turned on by default even for Linux guests. Check and
fail Hyper-V detection if we are on Xen.
[ hpa: the problem here is that Xen doesn't emulate Hyper-V well
enough, and if the Xen support isn't compiled in, we end up stubling
over the Hyper-V emulation and try to activate it -- and it fails. ]
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1359940959-32168-2-git-send-email-kys@microsoft.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
KY Srinivasan