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path: root/drivers/hv/channel.c
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2017-11-28Drivers: hv: vmbus: Fix a rescind issueK. Y. Srinivasan
The current rescind processing code will not correctly handle the case where the host immediately rescinds a channel that has been offerred. In this case, we could be blocked in the open call and since the channel is rescinded, the host will not respond and we could be blocked forever in the vmbus open call.i Fix this problem. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace channel eventsVitaly Kuznetsov
Added an additional set of trace points for when channel gets notified or signals host. Suggested-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace vmbus_send_tl_connect_request()Vitaly Kuznetsov
Add tracepoint to CHANNELMSG_TL_CONNECT_REQUEST sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace vmbus_teardown_gpadl()Vitaly Kuznetsov
Add tracepoint to CHANNELMSG_GPADL_TEARDOWN sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace vmbus_establish_gpadl()Vitaly Kuznetsov
Add tracepoint to CHANNELMSG_GPADL_HEADER/CHANNELMSG_GPADL_BODY sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace vmbus_close_internal()Vitaly Kuznetsov
Add tracepoint to CHANNELMSG_CLOSECHANNEL sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04hyper-v: trace vmbus_open()Vitaly Kuznetsov
Add tracepoint to CHANNELMSG_OPENCHANNEL sender. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-20vmbus: initialize reserved fields in messagesStephen Hemminger
Make sure and initialize reserved fields in messages to host, rather than passing stack junk. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-04Drivers: hv: vmbus: Fix bugs in rescind handlingK. Y. Srinivasan
This patch addresses the following bugs in the current rescind handling code: 1. Fixes a race condition where we may be invoking hv_process_channel_removal() on an already freed channel. 2. Prevents indefinite wait when rescinding sub-channels by correctly setting the probe_complete state. I would like to thank Dexuan for patiently reviewing earlier versions of this patch and identifying many of the issues fixed here. Greg, please apply this to 4.14-final. Fixes: '54a66265d675 ("Drivers: hv: vmbus: Fix rescind handling")' Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Cc: stable@vger.kernel.org # (4.13 and above) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Support ipv6 checksum offload in sunvnet driver, from Shannon Nelson. 2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric Dumazet. 3) Allow generic XDP to work on virtual devices, from John Fastabend. 4) Add bpf device maps and XDP_REDIRECT, which can be used to build arbitrary switching frameworks using XDP. From John Fastabend. 5) Remove UFO offloads from the tree, gave us little other than bugs. 6) Remove the IPSEC flow cache, from Florian Westphal. 7) Support ipv6 route offload in mlxsw driver. 8) Support VF representors in bnxt_en, from Sathya Perla. 9) Add support for forward error correction modes to ethtool, from Vidya Sagar Ravipati. 10) Add time filter for packet scheduler action dumping, from Jamal Hadi Salim. 11) Extend the zerocopy sendmsg() used by virtio and tap to regular sockets via MSG_ZEROCOPY. From Willem de Bruijn. 12) Significantly rework value tracking in the BPF verifier, from Edward Cree. 13) Add new jump instructions to eBPF, from Daniel Borkmann. 14) Rework rtnetlink plumbing so that operations can be run without taking the RTNL semaphore. From Florian Westphal. 15) Support XDP in tap driver, from Jason Wang. 16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal. 17) Add Huawei hinic ethernet driver. 18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan Delalande. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits) i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq i40e: avoid NVM acquire deadlock during NVM update drivers: net: xgene: Remove return statement from void function drivers: net: xgene: Configure tx/rx delay for ACPI drivers: net: xgene: Read tx/rx delay for ACPI rocker: fix kcalloc parameter order rds: Fix non-atomic operation on shared flag variable net: sched: don't use GFP_KERNEL under spin lock vhost_net: correctly check tx avail during rx busy polling net: mdio-mux: add mdio_mux parameter to mdio_mux_init() rxrpc: Make service connection lookup always check for retry net: stmmac: Delete dead code for MDIO registration gianfar: Fix Tx flow control deactivation cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6 cxgb4: Fix pause frame count in t4_get_port_stats cxgb4: fix memory leak tun: rename generic_xdp to skb_xdp tun: reserve extra headroom only when XDP is set net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping net: dsa: bcm_sf2: Advertise number of egress queues ...
2017-08-16vmbus: remove unused vmbus_sendpacket_ctlstephen hemminger
The only usage of vmbus_sendpacket_ctl was by vmbus_sendpacket. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16vmbus: remove unused vmubs_sendpacket_pagebuffer_ctlstephen hemminger
The function vmbus_sendpacket_pagebuffer_ctl was never used directly. Just have vmbus_send_pagebuffer Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16vmbus: remove unused vmbus_sendpacket_multipagebufferstephen hemminger
This function is not used anywhere in current code. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16Drivers: hv: vmbus: Fix rescind handling issuesK. Y. Srinivasan
This patch handles the following issues that were observed when we are handling racing channel offer message and rescind message for the same offer: 1. Since the host does not respond to messages on a rescinded channel, in the current code, we could be indefinitely blocked on the vmbus_open() call. 2. When a rescinded channel is being closed, if there is a pending interrupt on the channel, we could end up freeing the channel that the interrupt handler would run on. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Tested-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17vmbus: re-enable channel taskletStephen Hemminger
This problem shows up in 4.11 when netvsc driver is removed and reloaded. The problem is that the channel is closed during module removal and the tasklet for processing responses is disabled. When module is reloaded the channel is reopened but the tasklet is marked as disabled. The fix is to re-enable tasklet at the end of close which gets it back to the initial state. The issue is less urgent in 4.12 since network driver now uses NAPI and not the tasklet; and other VMBUS devices are rarely unloaded/reloaded. Fixes: dad72a1d2844 ("vmbus: remove hv_event_tasklet_disable/enable") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18Drivers: hv: vmbus: Fix rescind handlingK. Y. Srinivasan
Fix the rescind handling. This patch addresses the following rescind scenario that is currently not handled correctly: If a rescind were to be received while the offer is still being peocessed, we will be blocked indefinitely since the rescind message is handled on the same work element as the offer message. Fix this issue. I would like to thank Dexuan Cui <decui@microsoft.com> and Long Li <longli@microsoft.com> for working with me on this patch. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-27Merge 4.11-rc4 into char-misc-nextGreg Kroah-Hartman
We want the char-misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17vmbus: fix spelling errorsStephen Hemminger
Several spelling errors in comments Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16Drivers: hv: vmbus: Don't leak memory when a channel is rescindedK. Y. Srinivasan
When we close a channel that has been rescinded, we will leak memory since vmbus_teardown_gpadl() returns an error. Fix this so that we can properly cleanup the memory allocated to the ring buffers. Fixes: ccb61f8a99e6 ("Drivers: hv: vmbus: Fix a rescind handling bug") Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16vmbus: remove hv_event_tasklet_disable/enableDexuan Cui
With the recent introduction of per-channel tasklet, we need to update the way we handle the 3 concurrency issues: 1. hv_process_channel_removal -> percpu_channel_deq vs. vmbus_chan_sched -> list_for_each_entry(..., percpu_list); 2. vmbus_process_offer -> percpu_channel_enq/deq vs. vmbus_chan_sched. 3. vmbus_close_internal vs. the per-channel tasklet vmbus_on_event; The first 2 issues can be handled by Stephen's recent patch "vmbus: use rcu for per-cpu channel list", and the third issue can be handled by calling tasklet_disable in vmbus_close_internal here. We don't need the original hv_event_tasklet_disable/enable since we now use per-channel tasklet instead of the previous per-CPU tasklet, and actually we must remove them due to the side effect now: vmbus_process_offer -> hv_event_tasklet_enable -> tasklet_schedule will start the per-channel callback prematurely, cauing NULL dereferencing (the channel may haven't been properly configured to run the callback yet). Fixes: 631e63a9f346 ("vmbus: change to per channel tasklet") Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-09scripts/spelling.txt: add "disble(d)" pattern and fix typo instancesMasahiro Yamada
Fix typos and add the following to the scripts/spelling.txt: disble||disable disbled||disabled I kept the TSL2563_INT_DISBLED in /drivers/iio/light/tsl2563.c untouched. The macro is not referenced at all, but this commit is touching only comment blocks just in case. Link: http://lkml.kernel.org/r/1481573103-11329-20-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-14vmbus: remove conditional locking of vmbus_writeStephen Hemminger
All current usage of vmbus write uses the acquire_lock flag, therefore having it be optional is unnecessary. This also fixes a sparse warning since sparse doesn't like when a function has conditional locking. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14vmbus: change to per channel taskletStephen Hemminger
Make the event handling tasklet per channel rather than per-cpu. This allows for better fairness when getting lots of data on the same cpu. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-10vmbus: remove unused kickq argument to sendpacketStephen Hemminger
Since sendpacket no longer uses kickq argument remove it. Remove it no longer used xmit_more in sendpacket in netvsc as well. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-10vmbus: drop no longer used kick_q argumentStephen Hemminger
The flag to cause notification of host is unused after commit a01a291a282f7c2e ("Drivers: hv: vmbus: Base host signaling strictly on the ring state"). Therefore remove it from the ring buffer internal API. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-10vmbus: use kernel bitops for traversing interrupt maskStephen Hemminger
Use standard kernel operations for find first set bit to traverse the channel bit array. This has added benefit of speeding up lookup on 64 bit and because it uses find first set instruction. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10Drivers: hv: vmbus: Fix a rescind handling bugK. Y. Srinivasan
The host can rescind a channel that has been offered to the guest and once the channel is rescinded, the host does not respond to any requests on that channel. Deal with the case where the guest may be blocked waiting for a response from 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>
2017-01-10Drivers: hv: vmbus: Raise retry/wait limits in vmbus_post_msg()Vitaly Kuznetsov
DoS protection conditions were altered in WS2016 and now it's easy to get -EAGAIN returned from vmbus_post_msg() (e.g. when we try changing MTU on a netvsc device in a loop). All vmbus_post_msg() callers don't retry the operation and we usually end up with a non-functional device or crash. While host's DoS protection conditions are unknown to me my tests show that it can take up to 10 seconds before the message is sent so doing udelay() is not an option, we really need to sleep. Almost all vmbus_post_msg() callers are ready to sleep but there is one special case: vmbus_initiate_unload() which can be called from interrupt/NMI context and we can't sleep there. I'm also not sure about the lonely vmbus_send_tl_connect_request() which has no in-tree users but its external users are most likely waiting for the host to reply so sleeping there is also appropriate. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-07Drivers: hv: vmbus: On the read path cleanup the logic to interrupt the hostK. Y. Srinivasan
Signal the host when we determine the host is to be signaled - on th read path. The currrent code determines the need to signal in the ringbuffer code and actually issues the signal elsewhere. This can result in the host viewing this interrupt as spurious since the host may also poll the channel. Make the necessary adjustments. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-07Drivers: hv: vmbus: On write cleanup the logic to interrupt the hostK. Y. Srinivasan
Signal the host when we determine the host is to be signaled. The currrent code determines the need to signal in the ringbuffer code and actually issues the signal elsewhere. This can result in the host viewing this interrupt as spurious since the host may also poll the channel. Make the necessary adjustments. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-07Drivers: hv: vmbus: Base host signaling strictly on the ring stateK. Y. Srinivasan
One of the factors that can result in the host concluding that a given guest in mounting a DOS attack is if the guest generates interrupts to the host when the host is not expecting it. If these "spurious" interrupts reach a certain rate, the host can throttle the guest to minimize the impact. The host computation of the "expected number of interrupts" is strictly based on the ring transitions. Until the host logic is fixed, base the guest logic to interrupt solely on the ring state. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02Drivers: hv: ring_buffer: wrap around mappings for ring buffersVitaly Kuznetsov
Make it possible to always use a single memcpy() or to provide a direct link to a packet on the ring buffer by creating virtual mapping for two copies of the ring buffer with vmap(). Utilize currently empty hv_ringbuffer_cleanup() to do the unmap. While on it, replace sizeof(struct hv_ring_buffer) check in hv_ringbuffer_init() with BUILD_BUG_ON() as it is a compile time check. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02Drivers: hv: cleanup vmbus_open() for wrap around mappingsVitaly Kuznetsov
In preparation for doing wrap around mappings for ring buffers cleanup vmbus_open() function: - check that ring sizes are PAGE_SIZE aligned (they are for all in-kernel drivers now); - kfree(open_info) on error only after we kzalloc() it (not an issue as it is valid to call kfree(NULL); - rename poorly named labels; - use alloc_pages() instead of __get_free_pages() as we need struct page pointer for future. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: vmbus: Implement a mechanism to tag the channel for low latencyK. Y. Srinivasan
On Hyper-V, performance critical channels use the monitor mechanism to signal the host when the guest posts mesages for the host. This mechanism minimizes the hypervisor intercepts and also makes the host more efficient in that each time the host is woken up, it processes a batch of messages as opposed to just one. The goal here is improve the throughput and this is at the expense of increased latency. Implement a mechanism to let the client driver decide if latency is important. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: vmbus: Enable explicit signaling policy for NIC channelsK. Y. Srinivasan
For synthetic NIC channels, enable explicit signaling policy as netvsc wants to explicitly control when the host is to be signaled. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: vmbus: fix the race when querying & updating the percpu listDexuan Cui
There is a rare race when we remove an entry from the global list hv_context.percpu_list[cpu] in hv_process_channel_removal() -> percpu_channel_deq() -> list_del(): at this time, if vmbus_on_event() -> process_chn_event() -> pcpu_relid2channel() is trying to query the list, we can get the kernel fault. Similarly, we also have the issue in the code path: vmbus_process_offer() -> percpu_channel_enq(). We can resolve the issue by disabling the tasklet when updating the list. The patch also moves vmbus_release_relid() to a later place where the channel has been removed from the per-cpu and the global lists. Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: get rid of timeout in vmbus_open()Vitaly Kuznetsov
vmbus_teardown_gpadl() can result in infinite wait when it is called on 5 second timeout in vmbus_open(). The issue is caused by the fact that gpadl teardown operation won't ever succeed for an opened channel and the timeout isn't always enough. As a guest, we can always trust the host to respond to our request (and there is nothing we can do if it doesn't). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: don't leak memory in vmbus_establish_gpadl()Vitaly Kuznetsov
In some cases create_gpadl_header() allocates submessages but we never free them. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: get rid of redundant messagecount in create_gpadl_header()Vitaly Kuznetsov
We use messagecount only once in vmbus_establish_gpadl() to check if it is safe to iterate through the submsglist. We can just initialize the list header in all cases in create_gpadl_header() instead. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: Give control over how the ring access is serializedK. Y. Srinivasan
On the channel send side, many of the VMBUS device drivers explicity serialize access to the outgoing ring buffer. Give more control to the VMBUS device drivers in terms how to serialize accesss to the outgoing ring buffer. The default behavior will be to aquire the ring lock to preserve the current behavior. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: define a new VMBus message type for hvsockDexuan Cui
A function to send the type of message is also added. The coming net/hvsock driver will use this function to proactively request the host to offer a VMBus channel for a new hvsock connection. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: vmbus_sendpacket_ctl: hvsock: avoid unnecessary signalingDexuan Cui
When the hvsock channel's outbound ringbuffer is full (i.e., hv_ringbuffer_write() returns -EAGAIN), we should avoid the unnecessary signaling the host. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: ring_buffer: eliminate hv_ringbuffer_peek()Vitaly Kuznetsov
Currently, there is only one user for hv_ringbuffer_read()/ hv_ringbuffer_peak() functions and the usage of these functions is: - insecure as we drop ring_lock between them, someone else (in theory only) can acquire it in between; - non-optimal as we do a number of things (acquire/release the above mentioned lock, calculate available space on the ring, ...) twice and this path is performance-critical. Remove hv_ringbuffer_peek() moving the logic from __vmbus_recvpacket() to hv_ringbuffer_read(). Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: remove code duplication between ↵Vitaly Kuznetsov
vmbus_recvpacket()/vmbus_recvpacket_raw() vmbus_recvpacket() and vmbus_recvpacket_raw() are almost identical but there are two discrepancies: 1) vmbus_recvpacket() doesn't propagate errors from hv_ringbuffer_read() which looks like it is not desired. 2) There is an error message printed in packetlen > bufferlen case in vmbus_recvpacket(). I'm removing it as it is usless for users to see such messages and /vmbus_recvpacket_raw() doesn't have it. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: Fix a Host signaling bugK. Y. Srinivasan
Currently we have two policies for deciding when to signal the host: One based on the ring buffer state and the other based on what the VMBUS client driver wants to do. Consider the case when the client wants to explicitly control when to signal the host. In this case, if the client were to defer signaling, we will not be able to signal the host subsequently when the client does want to signal since the ring buffer state will prevent the signaling. Implement logic to have only one signaling policy in force for a given channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Tested-by: Haiyang Zhang <haiyangz@microsoft.com> Cc: <stable@vger.kernel.org> # v4.2+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: fix rescind-offer handling for device without a driverDexuan Cui
In the path vmbus_onoffer_rescind() -> vmbus_device_unregister() -> device_unregister() -> ... -> __device_release_driver(), we can see for a device without a driver loaded: dev->driver is NULL, so dev->bus->remove(dev), namely vmbus_remove(), isn't invoked. As a result, vmbus_remove() -> hv_process_channel_removal() isn't invoked and some cleanups(like sending a CHANNELMSG_RELID_RELEASED message to the host) aren't done. We can demo the issue this way: 1. rmmod hv_utils; 2. disable the Heartbeat Integration Service in Hyper-V Manager and lsvmbus shows the device disappears. 3. re-enable the Heartbeat in Hyper-V Manager and modprobe hv_utils, but lsvmbus shows the device can't appear again. This is because, the host thinks the VM hasn't released the relid, so can't re-offer the device to the VM. We can fix the issue by moving hv_process_channel_removal() from vmbus_close_internal() to vmbus_device_release(), since the latter is always invoked on device_unregister(), whether or not the dev has a driver loaded. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: do sanity check of channel state in vmbus_close_internal()Dexuan Cui
This fixes an incorrect assumption of channel state in the function. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: serialize process_chn_event() and vmbus_close_internal()Dexuan Cui
process_chn_event(), running in the tasklet, can race with vmbus_close_internal() in the case of SMP guest, e.g., when the former is accessing channel->inbound.ring_buffer, the latter could be freeing the ring_buffer pages. To resolve the race, we can serialize them by disabling the tasklet when the latter is running here. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04Drivers: hv: vmbus: Permit sending of packets without payloadK. Y. Srinivasan
The guest may have to send a completion packet back to the host. To support this usage, permit sending a packet without a payload - we would be only sending the descriptor in this case. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12Drivers: hv: vmbus: Allocate ring buffer memory in NUMA aware fashionK. Y. Srinivasan
Allocate ring buffer memory from the NUMA node assigned to the channel. Since this is a performance and not a correctness issue, if the node specific allocation were to fail, fall back and allocate without specifying the node. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>