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VMBus version 4.1 and later support the CHANNELMSG_MODIFYCHANNEL(22) message type which can be used to request Hyper-V to change the vCPU that a channel will interrupt. Introduce the CHANNELMSG_MODIFYCHANNEL message type, and define the vmbus_send_modifychannel() function to send CHANNELMSG_MODIFYCHANNEL requests to the host via a hypercall. The function is then used to define a sysfs "store" operation, which allows to change the (v)CPU the channel will interrupt by using the sysfs interface. The feature can be used for load balancing or other purposes. One interesting catch here is that Hyper-V can *not* currently ACK CHANNELMSG_MODIFYCHANNEL messages with the promise that (after the ACK is sent) the channel won't send any more interrupts to the "old" CPU. The peculiarity of the CHANNELMSG_MODIFYCHANNEL messages is problematic if the user want to take a CPU offline, since we don't want to take a CPU offline (and, potentially, "lose" channel interrupts on such CPU) if the host is still processing a CHANNELMSG_MODIFYCHANNEL message associated to that CPU. It is worth mentioning, however, that we have been unable to observe the above mentioned "race": in all our tests, CHANNELMSG_MODIFYCHANNEL requests appeared *as if* they were processed synchronously by the host. Suggested-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20200406001514.19876-11-parri.andrea@gmail.com Reviewed-by: Michael Kelley <mikelley@microsoft.com> [ wei: fix conflict in channel_mgmt.c ] Signed-off-by: Wei Liu <wei.liu@kernel.org>
943 lines
26 KiB
C
943 lines
26 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2009, Microsoft Corporation.
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*
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* Authors:
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* Haiyang Zhang <haiyangz@microsoft.com>
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* Hank Janssen <hjanssen@microsoft.com>
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/wait.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/hyperv.h>
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#include <linux/uio.h>
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#include <linux/interrupt.h>
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#include <asm/page.h>
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#include "hyperv_vmbus.h"
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#define NUM_PAGES_SPANNED(addr, len) \
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((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
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static unsigned long virt_to_hvpfn(void *addr)
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{
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phys_addr_t paddr;
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if (is_vmalloc_addr(addr))
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paddr = page_to_phys(vmalloc_to_page(addr)) +
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offset_in_page(addr);
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else
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paddr = __pa(addr);
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return paddr >> PAGE_SHIFT;
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}
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/*
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* vmbus_setevent- Trigger an event notification on the specified
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* channel.
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*/
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void vmbus_setevent(struct vmbus_channel *channel)
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{
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struct hv_monitor_page *monitorpage;
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trace_vmbus_setevent(channel);
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/*
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* For channels marked as in "low latency" mode
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* bypass the monitor page mechanism.
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*/
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if (channel->offermsg.monitor_allocated && !channel->low_latency) {
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vmbus_send_interrupt(channel->offermsg.child_relid);
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/* Get the child to parent monitor page */
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monitorpage = vmbus_connection.monitor_pages[1];
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sync_set_bit(channel->monitor_bit,
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(unsigned long *)&monitorpage->trigger_group
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[channel->monitor_grp].pending);
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} else {
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vmbus_set_event(channel);
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}
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}
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EXPORT_SYMBOL_GPL(vmbus_setevent);
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/* vmbus_free_ring - drop mapping of ring buffer */
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void vmbus_free_ring(struct vmbus_channel *channel)
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{
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hv_ringbuffer_cleanup(&channel->outbound);
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hv_ringbuffer_cleanup(&channel->inbound);
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if (channel->ringbuffer_page) {
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__free_pages(channel->ringbuffer_page,
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get_order(channel->ringbuffer_pagecount
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<< PAGE_SHIFT));
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channel->ringbuffer_page = NULL;
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}
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}
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EXPORT_SYMBOL_GPL(vmbus_free_ring);
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/* vmbus_alloc_ring - allocate and map pages for ring buffer */
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int vmbus_alloc_ring(struct vmbus_channel *newchannel,
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u32 send_size, u32 recv_size)
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{
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struct page *page;
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int order;
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if (send_size % PAGE_SIZE || recv_size % PAGE_SIZE)
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return -EINVAL;
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/* Allocate the ring buffer */
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order = get_order(send_size + recv_size);
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page = alloc_pages_node(cpu_to_node(newchannel->target_cpu),
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GFP_KERNEL|__GFP_ZERO, order);
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if (!page)
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page = alloc_pages(GFP_KERNEL|__GFP_ZERO, order);
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if (!page)
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return -ENOMEM;
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newchannel->ringbuffer_page = page;
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newchannel->ringbuffer_pagecount = (send_size + recv_size) >> PAGE_SHIFT;
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newchannel->ringbuffer_send_offset = send_size >> PAGE_SHIFT;
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return 0;
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}
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EXPORT_SYMBOL_GPL(vmbus_alloc_ring);
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static int __vmbus_open(struct vmbus_channel *newchannel,
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void *userdata, u32 userdatalen,
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void (*onchannelcallback)(void *context), void *context)
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{
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struct vmbus_channel_open_channel *open_msg;
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struct vmbus_channel_msginfo *open_info = NULL;
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struct page *page = newchannel->ringbuffer_page;
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u32 send_pages, recv_pages;
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unsigned long flags;
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int err;
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if (userdatalen > MAX_USER_DEFINED_BYTES)
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return -EINVAL;
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send_pages = newchannel->ringbuffer_send_offset;
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recv_pages = newchannel->ringbuffer_pagecount - send_pages;
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spin_lock_irqsave(&newchannel->lock, flags);
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if (newchannel->state != CHANNEL_OPEN_STATE) {
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spin_unlock_irqrestore(&newchannel->lock, flags);
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return -EINVAL;
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}
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spin_unlock_irqrestore(&newchannel->lock, flags);
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newchannel->state = CHANNEL_OPENING_STATE;
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newchannel->onchannel_callback = onchannelcallback;
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newchannel->channel_callback_context = context;
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err = hv_ringbuffer_init(&newchannel->outbound, page, send_pages);
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if (err)
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goto error_clean_ring;
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err = hv_ringbuffer_init(&newchannel->inbound,
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&page[send_pages], recv_pages);
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if (err)
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goto error_clean_ring;
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/* Establish the gpadl for the ring buffer */
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newchannel->ringbuffer_gpadlhandle = 0;
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err = vmbus_establish_gpadl(newchannel,
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page_address(newchannel->ringbuffer_page),
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(send_pages + recv_pages) << PAGE_SHIFT,
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&newchannel->ringbuffer_gpadlhandle);
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if (err)
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goto error_clean_ring;
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/* Create and init the channel open message */
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open_info = kmalloc(sizeof(*open_info) +
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sizeof(struct vmbus_channel_open_channel),
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GFP_KERNEL);
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if (!open_info) {
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err = -ENOMEM;
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goto error_free_gpadl;
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}
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init_completion(&open_info->waitevent);
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open_info->waiting_channel = newchannel;
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open_msg = (struct vmbus_channel_open_channel *)open_info->msg;
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open_msg->header.msgtype = CHANNELMSG_OPENCHANNEL;
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open_msg->openid = newchannel->offermsg.child_relid;
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open_msg->child_relid = newchannel->offermsg.child_relid;
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open_msg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
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open_msg->downstream_ringbuffer_pageoffset = newchannel->ringbuffer_send_offset;
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open_msg->target_vp = newchannel->target_vp;
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if (userdatalen)
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memcpy(open_msg->userdata, userdata, userdatalen);
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spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
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list_add_tail(&open_info->msglistentry,
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&vmbus_connection.chn_msg_list);
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spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
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if (newchannel->rescind) {
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err = -ENODEV;
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goto error_free_info;
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}
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err = vmbus_post_msg(open_msg,
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sizeof(struct vmbus_channel_open_channel), true);
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trace_vmbus_open(open_msg, err);
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if (err != 0)
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goto error_clean_msglist;
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wait_for_completion(&open_info->waitevent);
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spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
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list_del(&open_info->msglistentry);
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spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
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if (newchannel->rescind) {
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err = -ENODEV;
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goto error_free_info;
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}
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if (open_info->response.open_result.status) {
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err = -EAGAIN;
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goto error_free_info;
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}
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newchannel->state = CHANNEL_OPENED_STATE;
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kfree(open_info);
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return 0;
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error_clean_msglist:
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spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
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list_del(&open_info->msglistentry);
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spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
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error_free_info:
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kfree(open_info);
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error_free_gpadl:
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vmbus_teardown_gpadl(newchannel, newchannel->ringbuffer_gpadlhandle);
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newchannel->ringbuffer_gpadlhandle = 0;
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error_clean_ring:
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hv_ringbuffer_cleanup(&newchannel->outbound);
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hv_ringbuffer_cleanup(&newchannel->inbound);
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newchannel->state = CHANNEL_OPEN_STATE;
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return err;
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}
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/*
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* vmbus_connect_ring - Open the channel but reuse ring buffer
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*/
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int vmbus_connect_ring(struct vmbus_channel *newchannel,
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void (*onchannelcallback)(void *context), void *context)
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{
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return __vmbus_open(newchannel, NULL, 0, onchannelcallback, context);
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}
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EXPORT_SYMBOL_GPL(vmbus_connect_ring);
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/*
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* vmbus_open - Open the specified channel.
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*/
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int vmbus_open(struct vmbus_channel *newchannel,
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u32 send_ringbuffer_size, u32 recv_ringbuffer_size,
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void *userdata, u32 userdatalen,
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void (*onchannelcallback)(void *context), void *context)
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{
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int err;
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err = vmbus_alloc_ring(newchannel, send_ringbuffer_size,
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recv_ringbuffer_size);
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if (err)
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return err;
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err = __vmbus_open(newchannel, userdata, userdatalen,
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onchannelcallback, context);
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if (err)
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vmbus_free_ring(newchannel);
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return err;
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}
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EXPORT_SYMBOL_GPL(vmbus_open);
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/* Used for Hyper-V Socket: a guest client's connect() to the host */
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int vmbus_send_tl_connect_request(const guid_t *shv_guest_servie_id,
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const guid_t *shv_host_servie_id)
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{
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struct vmbus_channel_tl_connect_request conn_msg;
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int ret;
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memset(&conn_msg, 0, sizeof(conn_msg));
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conn_msg.header.msgtype = CHANNELMSG_TL_CONNECT_REQUEST;
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conn_msg.guest_endpoint_id = *shv_guest_servie_id;
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conn_msg.host_service_id = *shv_host_servie_id;
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ret = vmbus_post_msg(&conn_msg, sizeof(conn_msg), true);
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trace_vmbus_send_tl_connect_request(&conn_msg, ret);
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return ret;
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}
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EXPORT_SYMBOL_GPL(vmbus_send_tl_connect_request);
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/*
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* Set/change the vCPU (@target_vp) the channel (@child_relid) will interrupt.
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*
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* CHANNELMSG_MODIFYCHANNEL messages are aynchronous. Also, Hyper-V does not
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* ACK such messages. IOW we can't know when the host will stop interrupting
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* the "old" vCPU and start interrupting the "new" vCPU for the given channel.
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*
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* The CHANNELMSG_MODIFYCHANNEL message type is supported since VMBus version
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* VERSION_WIN10_V4_1.
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*/
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int vmbus_send_modifychannel(u32 child_relid, u32 target_vp)
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{
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struct vmbus_channel_modifychannel conn_msg;
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int ret;
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memset(&conn_msg, 0, sizeof(conn_msg));
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conn_msg.header.msgtype = CHANNELMSG_MODIFYCHANNEL;
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conn_msg.child_relid = child_relid;
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conn_msg.target_vp = target_vp;
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ret = vmbus_post_msg(&conn_msg, sizeof(conn_msg), true);
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trace_vmbus_send_modifychannel(&conn_msg, ret);
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return ret;
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}
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EXPORT_SYMBOL_GPL(vmbus_send_modifychannel);
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/*
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* create_gpadl_header - Creates a gpadl for the specified buffer
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*/
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static int create_gpadl_header(void *kbuffer, u32 size,
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struct vmbus_channel_msginfo **msginfo)
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{
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int i;
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int pagecount;
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struct vmbus_channel_gpadl_header *gpadl_header;
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struct vmbus_channel_gpadl_body *gpadl_body;
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struct vmbus_channel_msginfo *msgheader;
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struct vmbus_channel_msginfo *msgbody = NULL;
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u32 msgsize;
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int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
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pagecount = size >> PAGE_SHIFT;
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/* do we need a gpadl body msg */
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pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
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sizeof(struct vmbus_channel_gpadl_header) -
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sizeof(struct gpa_range);
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pfncount = pfnsize / sizeof(u64);
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if (pagecount > pfncount) {
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/* we need a gpadl body */
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/* fill in the header */
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msgsize = sizeof(struct vmbus_channel_msginfo) +
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sizeof(struct vmbus_channel_gpadl_header) +
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sizeof(struct gpa_range) + pfncount * sizeof(u64);
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msgheader = kzalloc(msgsize, GFP_KERNEL);
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if (!msgheader)
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goto nomem;
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INIT_LIST_HEAD(&msgheader->submsglist);
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msgheader->msgsize = msgsize;
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gpadl_header = (struct vmbus_channel_gpadl_header *)
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msgheader->msg;
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gpadl_header->rangecount = 1;
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gpadl_header->range_buflen = sizeof(struct gpa_range) +
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pagecount * sizeof(u64);
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gpadl_header->range[0].byte_offset = 0;
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gpadl_header->range[0].byte_count = size;
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for (i = 0; i < pfncount; i++)
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gpadl_header->range[0].pfn_array[i] = virt_to_hvpfn(
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kbuffer + PAGE_SIZE * i);
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*msginfo = msgheader;
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pfnsum = pfncount;
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pfnleft = pagecount - pfncount;
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/* how many pfns can we fit */
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pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
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sizeof(struct vmbus_channel_gpadl_body);
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pfncount = pfnsize / sizeof(u64);
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/* fill in the body */
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while (pfnleft) {
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if (pfnleft > pfncount)
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pfncurr = pfncount;
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else
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pfncurr = pfnleft;
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msgsize = sizeof(struct vmbus_channel_msginfo) +
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sizeof(struct vmbus_channel_gpadl_body) +
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pfncurr * sizeof(u64);
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msgbody = kzalloc(msgsize, GFP_KERNEL);
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if (!msgbody) {
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struct vmbus_channel_msginfo *pos = NULL;
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struct vmbus_channel_msginfo *tmp = NULL;
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/*
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* Free up all the allocated messages.
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*/
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list_for_each_entry_safe(pos, tmp,
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&msgheader->submsglist,
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msglistentry) {
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list_del(&pos->msglistentry);
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kfree(pos);
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}
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goto nomem;
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}
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msgbody->msgsize = msgsize;
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gpadl_body =
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(struct vmbus_channel_gpadl_body *)msgbody->msg;
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/*
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* Gpadl is u32 and we are using a pointer which could
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* be 64-bit
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* This is governed by the guest/host protocol and
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* so the hypervisor guarantees that this is ok.
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*/
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for (i = 0; i < pfncurr; i++)
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gpadl_body->pfn[i] = virt_to_hvpfn(
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kbuffer + PAGE_SIZE * (pfnsum + i));
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/* add to msg header */
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list_add_tail(&msgbody->msglistentry,
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&msgheader->submsglist);
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pfnsum += pfncurr;
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pfnleft -= pfncurr;
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}
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} else {
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/* everything fits in a header */
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msgsize = sizeof(struct vmbus_channel_msginfo) +
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sizeof(struct vmbus_channel_gpadl_header) +
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sizeof(struct gpa_range) + pagecount * sizeof(u64);
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msgheader = kzalloc(msgsize, GFP_KERNEL);
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if (msgheader == NULL)
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goto nomem;
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|
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INIT_LIST_HEAD(&msgheader->submsglist);
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msgheader->msgsize = msgsize;
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gpadl_header = (struct vmbus_channel_gpadl_header *)
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msgheader->msg;
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gpadl_header->rangecount = 1;
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gpadl_header->range_buflen = sizeof(struct gpa_range) +
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pagecount * sizeof(u64);
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gpadl_header->range[0].byte_offset = 0;
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gpadl_header->range[0].byte_count = size;
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for (i = 0; i < pagecount; i++)
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gpadl_header->range[0].pfn_array[i] = virt_to_hvpfn(
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kbuffer + PAGE_SIZE * i);
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|
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*msginfo = msgheader;
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}
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|
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return 0;
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|
nomem:
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kfree(msgheader);
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kfree(msgbody);
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return -ENOMEM;
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}
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|
|
/*
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|
* vmbus_establish_gpadl - Establish a GPADL for the specified buffer
|
|
*
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* @channel: a channel
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* @kbuffer: from kmalloc or vmalloc
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* @size: page-size multiple
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* @gpadl_handle: some funky thing
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*/
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int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
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u32 size, u32 *gpadl_handle)
|
|
{
|
|
struct vmbus_channel_gpadl_header *gpadlmsg;
|
|
struct vmbus_channel_gpadl_body *gpadl_body;
|
|
struct vmbus_channel_msginfo *msginfo = NULL;
|
|
struct vmbus_channel_msginfo *submsginfo, *tmp;
|
|
struct list_head *curr;
|
|
u32 next_gpadl_handle;
|
|
unsigned long flags;
|
|
int ret = 0;
|
|
|
|
next_gpadl_handle =
|
|
(atomic_inc_return(&vmbus_connection.next_gpadl_handle) - 1);
|
|
|
|
ret = create_gpadl_header(kbuffer, size, &msginfo);
|
|
if (ret)
|
|
return ret;
|
|
|
|
init_completion(&msginfo->waitevent);
|
|
msginfo->waiting_channel = channel;
|
|
|
|
gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
|
|
gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
|
|
gpadlmsg->child_relid = channel->offermsg.child_relid;
|
|
gpadlmsg->gpadl = next_gpadl_handle;
|
|
|
|
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
list_add_tail(&msginfo->msglistentry,
|
|
&vmbus_connection.chn_msg_list);
|
|
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
if (channel->rescind) {
|
|
ret = -ENODEV;
|
|
goto cleanup;
|
|
}
|
|
|
|
ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
|
|
sizeof(*msginfo), true);
|
|
|
|
trace_vmbus_establish_gpadl_header(gpadlmsg, ret);
|
|
|
|
if (ret != 0)
|
|
goto cleanup;
|
|
|
|
list_for_each(curr, &msginfo->submsglist) {
|
|
submsginfo = (struct vmbus_channel_msginfo *)curr;
|
|
gpadl_body =
|
|
(struct vmbus_channel_gpadl_body *)submsginfo->msg;
|
|
|
|
gpadl_body->header.msgtype =
|
|
CHANNELMSG_GPADL_BODY;
|
|
gpadl_body->gpadl = next_gpadl_handle;
|
|
|
|
ret = vmbus_post_msg(gpadl_body,
|
|
submsginfo->msgsize - sizeof(*submsginfo),
|
|
true);
|
|
|
|
trace_vmbus_establish_gpadl_body(gpadl_body, ret);
|
|
|
|
if (ret != 0)
|
|
goto cleanup;
|
|
|
|
}
|
|
wait_for_completion(&msginfo->waitevent);
|
|
|
|
if (msginfo->response.gpadl_created.creation_status != 0) {
|
|
pr_err("Failed to establish GPADL: err = 0x%x\n",
|
|
msginfo->response.gpadl_created.creation_status);
|
|
|
|
ret = -EDQUOT;
|
|
goto cleanup;
|
|
}
|
|
|
|
if (channel->rescind) {
|
|
ret = -ENODEV;
|
|
goto cleanup;
|
|
}
|
|
|
|
/* At this point, we received the gpadl created msg */
|
|
*gpadl_handle = gpadlmsg->gpadl;
|
|
|
|
cleanup:
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
list_del(&msginfo->msglistentry);
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
list_for_each_entry_safe(submsginfo, tmp, &msginfo->submsglist,
|
|
msglistentry) {
|
|
kfree(submsginfo);
|
|
}
|
|
|
|
kfree(msginfo);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
|
|
|
|
/*
|
|
* vmbus_teardown_gpadl -Teardown the specified GPADL handle
|
|
*/
|
|
int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
|
|
{
|
|
struct vmbus_channel_gpadl_teardown *msg;
|
|
struct vmbus_channel_msginfo *info;
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
info = kmalloc(sizeof(*info) +
|
|
sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
|
|
if (!info)
|
|
return -ENOMEM;
|
|
|
|
init_completion(&info->waitevent);
|
|
info->waiting_channel = channel;
|
|
|
|
msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
|
|
|
|
msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
|
|
msg->child_relid = channel->offermsg.child_relid;
|
|
msg->gpadl = gpadl_handle;
|
|
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
list_add_tail(&info->msglistentry,
|
|
&vmbus_connection.chn_msg_list);
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
if (channel->rescind)
|
|
goto post_msg_err;
|
|
|
|
ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_gpadl_teardown),
|
|
true);
|
|
|
|
trace_vmbus_teardown_gpadl(msg, ret);
|
|
|
|
if (ret)
|
|
goto post_msg_err;
|
|
|
|
wait_for_completion(&info->waitevent);
|
|
|
|
post_msg_err:
|
|
/*
|
|
* If the channel has been rescinded;
|
|
* we will be awakened by the rescind
|
|
* handler; set the error code to zero so we don't leak memory.
|
|
*/
|
|
if (channel->rescind)
|
|
ret = 0;
|
|
|
|
spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
|
|
list_del(&info->msglistentry);
|
|
spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
|
|
|
|
kfree(info);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
|
|
|
|
void vmbus_reset_channel_cb(struct vmbus_channel *channel)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* vmbus_on_event(), running in the per-channel 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, so here we must stop it
|
|
* first.
|
|
*
|
|
* vmbus_chan_sched() might call the netvsc driver callback function
|
|
* that ends up scheduling NAPI work that accesses the ring buffer.
|
|
* At this point, we have to ensure that any such work is completed
|
|
* and that the channel ring buffer is no longer being accessed, cf.
|
|
* the calls to napi_disable() in netvsc_device_remove().
|
|
*/
|
|
tasklet_disable(&channel->callback_event);
|
|
|
|
/* See the inline comments in vmbus_chan_sched(). */
|
|
spin_lock_irqsave(&channel->sched_lock, flags);
|
|
channel->onchannel_callback = NULL;
|
|
spin_unlock_irqrestore(&channel->sched_lock, flags);
|
|
|
|
channel->sc_creation_callback = NULL;
|
|
|
|
/* Re-enable tasklet for use on re-open */
|
|
tasklet_enable(&channel->callback_event);
|
|
}
|
|
|
|
static int vmbus_close_internal(struct vmbus_channel *channel)
|
|
{
|
|
struct vmbus_channel_close_channel *msg;
|
|
int ret;
|
|
|
|
vmbus_reset_channel_cb(channel);
|
|
|
|
/*
|
|
* In case a device driver's probe() fails (e.g.,
|
|
* util_probe() -> vmbus_open() returns -ENOMEM) and the device is
|
|
* rescinded later (e.g., we dynamically disable an Integrated Service
|
|
* in Hyper-V Manager), the driver's remove() invokes vmbus_close():
|
|
* here we should skip most of the below cleanup work.
|
|
*/
|
|
if (channel->state != CHANNEL_OPENED_STATE)
|
|
return -EINVAL;
|
|
|
|
channel->state = CHANNEL_OPEN_STATE;
|
|
|
|
/* Send a closing message */
|
|
|
|
msg = &channel->close_msg.msg;
|
|
|
|
msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
|
|
msg->child_relid = channel->offermsg.child_relid;
|
|
|
|
ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel),
|
|
true);
|
|
|
|
trace_vmbus_close_internal(msg, ret);
|
|
|
|
if (ret) {
|
|
pr_err("Close failed: close post msg return is %d\n", ret);
|
|
/*
|
|
* If we failed to post the close msg,
|
|
* it is perhaps better to leak memory.
|
|
*/
|
|
}
|
|
|
|
/* Tear down the gpadl for the channel's ring buffer */
|
|
else if (channel->ringbuffer_gpadlhandle) {
|
|
ret = vmbus_teardown_gpadl(channel,
|
|
channel->ringbuffer_gpadlhandle);
|
|
if (ret) {
|
|
pr_err("Close failed: teardown gpadl return %d\n", ret);
|
|
/*
|
|
* If we failed to teardown gpadl,
|
|
* it is perhaps better to leak memory.
|
|
*/
|
|
}
|
|
|
|
channel->ringbuffer_gpadlhandle = 0;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* disconnect ring - close all channels */
|
|
int vmbus_disconnect_ring(struct vmbus_channel *channel)
|
|
{
|
|
struct vmbus_channel *cur_channel, *tmp;
|
|
int ret;
|
|
|
|
if (channel->primary_channel != NULL)
|
|
return -EINVAL;
|
|
|
|
list_for_each_entry_safe(cur_channel, tmp, &channel->sc_list, sc_list) {
|
|
if (cur_channel->rescind)
|
|
wait_for_completion(&cur_channel->rescind_event);
|
|
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
if (vmbus_close_internal(cur_channel) == 0) {
|
|
vmbus_free_ring(cur_channel);
|
|
|
|
if (cur_channel->rescind)
|
|
hv_process_channel_removal(cur_channel);
|
|
}
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
}
|
|
|
|
/*
|
|
* Now close the primary.
|
|
*/
|
|
mutex_lock(&vmbus_connection.channel_mutex);
|
|
ret = vmbus_close_internal(channel);
|
|
mutex_unlock(&vmbus_connection.channel_mutex);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_disconnect_ring);
|
|
|
|
/*
|
|
* vmbus_close - Close the specified channel
|
|
*/
|
|
void vmbus_close(struct vmbus_channel *channel)
|
|
{
|
|
if (vmbus_disconnect_ring(channel) == 0)
|
|
vmbus_free_ring(channel);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_close);
|
|
|
|
/**
|
|
* vmbus_sendpacket() - Send the specified buffer on the given channel
|
|
* @channel: Pointer to vmbus_channel structure
|
|
* @buffer: Pointer to the buffer you want to send the data from.
|
|
* @bufferlen: Maximum size of what the buffer holds.
|
|
* @requestid: Identifier of the request
|
|
* @type: Type of packet that is being sent e.g. negotiate, time
|
|
* packet etc.
|
|
* @flags: 0 or VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED
|
|
*
|
|
* Sends data in @buffer directly to Hyper-V via the vmbus.
|
|
* This will send the data unparsed to Hyper-V.
|
|
*
|
|
* Mainly used by Hyper-V drivers.
|
|
*/
|
|
int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
|
|
u32 bufferlen, u64 requestid,
|
|
enum vmbus_packet_type type, u32 flags)
|
|
{
|
|
struct vmpacket_descriptor desc;
|
|
u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
|
|
u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
|
|
struct kvec bufferlist[3];
|
|
u64 aligned_data = 0;
|
|
int num_vecs = ((bufferlen != 0) ? 3 : 1);
|
|
|
|
|
|
/* Setup the descriptor */
|
|
desc.type = type; /* VmbusPacketTypeDataInBand; */
|
|
desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
|
|
/* in 8-bytes granularity */
|
|
desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
|
|
desc.len8 = (u16)(packetlen_aligned >> 3);
|
|
desc.trans_id = requestid;
|
|
|
|
bufferlist[0].iov_base = &desc;
|
|
bufferlist[0].iov_len = sizeof(struct vmpacket_descriptor);
|
|
bufferlist[1].iov_base = buffer;
|
|
bufferlist[1].iov_len = bufferlen;
|
|
bufferlist[2].iov_base = &aligned_data;
|
|
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
|
|
|
|
return hv_ringbuffer_write(channel, bufferlist, num_vecs);
|
|
}
|
|
EXPORT_SYMBOL(vmbus_sendpacket);
|
|
|
|
/*
|
|
* vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
|
|
* packets using a GPADL Direct packet type. This interface allows you
|
|
* to control notifying the host. This will be useful for sending
|
|
* batched data. Also the sender can control the send flags
|
|
* explicitly.
|
|
*/
|
|
int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
|
|
struct hv_page_buffer pagebuffers[],
|
|
u32 pagecount, void *buffer, u32 bufferlen,
|
|
u64 requestid)
|
|
{
|
|
int i;
|
|
struct vmbus_channel_packet_page_buffer desc;
|
|
u32 descsize;
|
|
u32 packetlen;
|
|
u32 packetlen_aligned;
|
|
struct kvec bufferlist[3];
|
|
u64 aligned_data = 0;
|
|
|
|
if (pagecount > MAX_PAGE_BUFFER_COUNT)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Adjust the size down since vmbus_channel_packet_page_buffer is the
|
|
* largest size we support
|
|
*/
|
|
descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
|
|
((MAX_PAGE_BUFFER_COUNT - pagecount) *
|
|
sizeof(struct hv_page_buffer));
|
|
packetlen = descsize + bufferlen;
|
|
packetlen_aligned = ALIGN(packetlen, sizeof(u64));
|
|
|
|
/* Setup the descriptor */
|
|
desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
|
|
desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
|
|
desc.dataoffset8 = descsize >> 3; /* in 8-bytes granularity */
|
|
desc.length8 = (u16)(packetlen_aligned >> 3);
|
|
desc.transactionid = requestid;
|
|
desc.reserved = 0;
|
|
desc.rangecount = pagecount;
|
|
|
|
for (i = 0; i < pagecount; i++) {
|
|
desc.range[i].len = pagebuffers[i].len;
|
|
desc.range[i].offset = pagebuffers[i].offset;
|
|
desc.range[i].pfn = pagebuffers[i].pfn;
|
|
}
|
|
|
|
bufferlist[0].iov_base = &desc;
|
|
bufferlist[0].iov_len = descsize;
|
|
bufferlist[1].iov_base = buffer;
|
|
bufferlist[1].iov_len = bufferlen;
|
|
bufferlist[2].iov_base = &aligned_data;
|
|
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
|
|
|
|
return hv_ringbuffer_write(channel, bufferlist, 3);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
|
|
|
|
/*
|
|
* vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
|
|
* using a GPADL Direct packet type.
|
|
* The buffer includes the vmbus descriptor.
|
|
*/
|
|
int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel,
|
|
struct vmbus_packet_mpb_array *desc,
|
|
u32 desc_size,
|
|
void *buffer, u32 bufferlen, u64 requestid)
|
|
{
|
|
u32 packetlen;
|
|
u32 packetlen_aligned;
|
|
struct kvec bufferlist[3];
|
|
u64 aligned_data = 0;
|
|
|
|
packetlen = desc_size + bufferlen;
|
|
packetlen_aligned = ALIGN(packetlen, sizeof(u64));
|
|
|
|
/* Setup the descriptor */
|
|
desc->type = VM_PKT_DATA_USING_GPA_DIRECT;
|
|
desc->flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
|
|
desc->dataoffset8 = desc_size >> 3; /* in 8-bytes granularity */
|
|
desc->length8 = (u16)(packetlen_aligned >> 3);
|
|
desc->transactionid = requestid;
|
|
desc->reserved = 0;
|
|
desc->rangecount = 1;
|
|
|
|
bufferlist[0].iov_base = desc;
|
|
bufferlist[0].iov_len = desc_size;
|
|
bufferlist[1].iov_base = buffer;
|
|
bufferlist[1].iov_len = bufferlen;
|
|
bufferlist[2].iov_base = &aligned_data;
|
|
bufferlist[2].iov_len = (packetlen_aligned - packetlen);
|
|
|
|
return hv_ringbuffer_write(channel, bufferlist, 3);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_sendpacket_mpb_desc);
|
|
|
|
/**
|
|
* __vmbus_recvpacket() - Retrieve the user packet on the specified channel
|
|
* @channel: Pointer to vmbus_channel structure
|
|
* @buffer: Pointer to the buffer you want to receive the data into.
|
|
* @bufferlen: Maximum size of what the buffer can hold.
|
|
* @buffer_actual_len: The actual size of the data after it was received.
|
|
* @requestid: Identifier of the request
|
|
* @raw: true means keep the vmpacket_descriptor header in the received data.
|
|
*
|
|
* Receives directly from the hyper-v vmbus and puts the data it received
|
|
* into Buffer. This will receive the data unparsed from hyper-v.
|
|
*
|
|
* Mainly used by Hyper-V drivers.
|
|
*/
|
|
static inline int
|
|
__vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
|
|
u32 bufferlen, u32 *buffer_actual_len, u64 *requestid,
|
|
bool raw)
|
|
{
|
|
return hv_ringbuffer_read(channel, buffer, bufferlen,
|
|
buffer_actual_len, requestid, raw);
|
|
|
|
}
|
|
|
|
int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
|
|
u32 bufferlen, u32 *buffer_actual_len,
|
|
u64 *requestid)
|
|
{
|
|
return __vmbus_recvpacket(channel, buffer, bufferlen,
|
|
buffer_actual_len, requestid, false);
|
|
}
|
|
EXPORT_SYMBOL(vmbus_recvpacket);
|
|
|
|
/*
|
|
* vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
|
|
*/
|
|
int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
|
|
u32 bufferlen, u32 *buffer_actual_len,
|
|
u64 *requestid)
|
|
{
|
|
return __vmbus_recvpacket(channel, buffer, bufferlen,
|
|
buffer_actual_len, requestid, true);
|
|
}
|
|
EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
|