--- /dev/null
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * Hyper-V virtual machine bus
+ *
+ */
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <byteswap.h>
+#include <ipxe/nap.h>
+#include <ipxe/malloc.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/hyperv.h>
+#include <ipxe/vmbus.h>
+
+/** VMBus initial GPADL ID
+ *
+ * This is an opaque value with no meaning. The Linux kernel uses
+ * 0xe1e10.
+ */
+#define VMBUS_GPADL_MAGIC 0x18ae0000
+
+/**
+ * Post message
+ *
+ * @v hv Hyper-V hypervisor
+ * @v header Message header
+ * @v len Length of message (including header)
+ * @ret rc Return status code
+ */
+static int vmbus_post_message ( struct hv_hypervisor *hv,
+ const struct vmbus_message_header *header,
+ size_t len ) {
+ struct vmbus *vmbus = hv->vmbus;
+ int rc;
+
+ /* Post message */
+ if ( ( rc = hv_post_message ( hv, VMBUS_MESSAGE_ID, VMBUS_MESSAGE_TYPE,
+ header, len ) ) != 0 ) {
+ DBGC ( vmbus, "VMBUS %p could not post message: %s\n",
+ vmbus, strerror ( rc ) );
+ return rc;
+ }
+
+ return 0;
+}
+
+/**
+ * Post empty message
+ *
+ * @v hv Hyper-V hypervisor
+ * @v type Message type
+ * @ret rc Return status code
+ */
+static int vmbus_post_empty_message ( struct hv_hypervisor *hv,
+ unsigned int type ) {
+ struct vmbus_message_header header = { .type = cpu_to_le32 ( type ) };
+
+ return vmbus_post_message ( hv, &header, sizeof ( header ) );
+}
+
+/**
+ * Wait for received message
+ *
+ * @v hv Hyper-V hypervisor
+ * @ret rc Return status code
+ */
+static int vmbus_wait_for_message ( struct hv_hypervisor *hv ) {
+ struct vmbus *vmbus = hv->vmbus;
+ int rc;
+
+ /* Wait for message */
+ if ( ( rc = hv_wait_for_message ( hv, VMBUS_MESSAGE_SINT ) ) != 0 ) {
+ DBGC ( vmbus, "VMBUS %p failed waiting for message: %s\n",
+ vmbus, strerror ( rc ) );
+ return rc;
+ }
+
+ /* Sanity check */
+ if ( hv->message->received.type != cpu_to_le32 ( VMBUS_MESSAGE_TYPE ) ){
+ DBGC ( vmbus, "VMBUS %p invalid message type %d\n",
+ vmbus, le32_to_cpu ( hv->message->received.type ) );
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * Initiate contact
+ *
+ * @v hv Hyper-V hypervisor
+ * @v raw VMBus protocol (raw) version
+ * @ret rc Return status code
+ */
+static int vmbus_initiate_contact ( struct hv_hypervisor *hv,
+ unsigned int raw ) {
+ struct vmbus *vmbus = hv->vmbus;
+ const struct vmbus_version_response *version = &vmbus->message->version;
+ struct vmbus_initiate_contact initiate;
+ int rc;
+
+ /* Construct message */
+ memset ( &initiate, 0, sizeof ( initiate ) );
+ initiate.header.type = cpu_to_le32 ( VMBUS_INITIATE_CONTACT );
+ initiate.version.raw = cpu_to_le32 ( raw );
+ initiate.intr = virt_to_phys ( vmbus->intr );
+ initiate.monitor_in = virt_to_phys ( vmbus->monitor_in );
+ initiate.monitor_out = virt_to_phys ( vmbus->monitor_out );
+
+ /* Post message */
+ if ( ( rc = vmbus_post_message ( hv, &initiate.header,
+ sizeof ( initiate ) ) ) != 0 )
+ return rc;
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ return rc;
+
+ /* Check response */
+ if ( version->header.type != cpu_to_le32 ( VMBUS_VERSION_RESPONSE ) ) {
+ DBGC ( vmbus, "VMBUS %p unexpected version response type %d\n",
+ vmbus, le32_to_cpu ( version->header.type ) );
+ return -EPROTO;
+ }
+ if ( ! version->supported ) {
+ DBGC ( vmbus, "VMBUS %p requested version not supported\n",
+ vmbus );
+ return -ENOTSUP;
+ }
+ if ( version->version.raw != cpu_to_le32 ( raw ) ) {
+ DBGC ( vmbus, "VMBUS %p unexpected version %d.%d\n",
+ vmbus, le16_to_cpu ( version->version.major ),
+ le16_to_cpu ( version->version.minor ) );
+ return -EPROTO;
+ }
+
+ DBGC ( vmbus, "VMBUS %p initiated contact using version %d.%d\n",
+ vmbus, le16_to_cpu ( version->version.major ),
+ le16_to_cpu ( version->version.minor ) );
+ return 0;
+}
+
+/**
+ * Terminate contact
+ *
+ * @v hv Hyper-V hypervisor
+ * @ret rc Return status code
+ */
+static int vmbus_unload ( struct hv_hypervisor *hv ) {
+ struct vmbus *vmbus = hv->vmbus;
+ const struct vmbus_message_header *header = &vmbus->message->header;
+ int rc;
+
+ /* Post message */
+ if ( ( rc = vmbus_post_empty_message ( hv, VMBUS_UNLOAD ) ) != 0 )
+ return rc;
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ return rc;
+
+ /* Check response */
+ if ( header->type != cpu_to_le32 ( VMBUS_UNLOAD_RESPONSE ) ) {
+ DBGC ( vmbus, "VMBUS %p unexpected unload response type %d\n",
+ vmbus, le32_to_cpu ( header->type ) );
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+/**
+ * Negotiate protocol version
+ *
+ * @v hv Hyper-V hypervisor
+ * @ret rc Return status code
+ */
+static int vmbus_negotiate_version ( struct hv_hypervisor *hv ) {
+ int rc;
+
+ /* We require the ability to disconnect from and reconnect to
+ * VMBus; if we don't have this then there is no (viable) way
+ * for a loaded operating system to continue to use any VMBus
+ * devices. (There is also a small but non-zero risk that the
+ * host will continue to write to our interrupt and monitor
+ * pages, since the VMBUS_UNLOAD message in earlier versions
+ * is essentially a no-op.)
+ *
+ * This requires us to ensure that the host supports protocol
+ * version 3.0 (VMBUS_VERSION_WIN8_1). However, we can't
+ * actually _use_ protocol version 3.0, since doing so causes
+ * an iSCSI-booted Windows Server 2012 R2 VM to crash due to a
+ * NULL pointer dereference in vmbus.sys.
+ *
+ * To work around this problem, we first ensure that we can
+ * connect using protocol v3.0, then disconnect and reconnect
+ * using the oldest known protocol.
+ */
+
+ /* Initiate contact to check for required protocol support */
+ if ( ( rc = vmbus_initiate_contact ( hv, VMBUS_VERSION_WIN8_1 ) ) != 0 )
+ return rc;
+
+ /* Terminate contact */
+ if ( ( rc = vmbus_unload ( hv ) ) != 0 )
+ return rc;
+
+ /* Reinitiate contact using the oldest known protocol version */
+ if ( ( rc = vmbus_initiate_contact ( hv, VMBUS_VERSION_WS2008 ) ) != 0 )
+ return rc;
+
+ return 0;
+}
+
+/**
+ * Establish GPA descriptor list
+ *
+ * @v vmdev VMBus device
+ * @v data Data buffer
+ * @v len Length of data buffer
+ * @ret gpadl GPADL ID, or negative error
+ */
+int vmbus_establish_gpadl ( struct vmbus_device *vmdev, userptr_t data,
+ size_t len ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus *vmbus = hv->vmbus;
+ physaddr_t addr = user_to_phys ( data, 0 );
+ unsigned int pfn_count = hv_pfn_count ( addr, len );
+ struct {
+ struct vmbus_gpadl_header gpadlhdr;
+ struct vmbus_gpa_range range;
+ uint64_t pfn[pfn_count];
+ } __attribute__ (( packed )) gpadlhdr;
+ const struct vmbus_gpadl_created *created = &vmbus->message->created;
+ static unsigned int gpadl = VMBUS_GPADL_MAGIC;
+ unsigned int i;
+ int rc;
+
+ /* Allocate GPADL ID */
+ gpadl++;
+
+ /* Construct message */
+ memset ( &gpadlhdr, 0, sizeof ( gpadlhdr ) );
+ gpadlhdr.gpadlhdr.header.type = cpu_to_le32 ( VMBUS_GPADL_HEADER );
+ gpadlhdr.gpadlhdr.channel = cpu_to_le32 ( vmdev->channel );
+ gpadlhdr.gpadlhdr.gpadl = cpu_to_le32 ( gpadl );
+ gpadlhdr.gpadlhdr.range_len =
+ cpu_to_le16 ( ( sizeof ( gpadlhdr.range ) +
+ sizeof ( gpadlhdr.pfn ) ) );
+ gpadlhdr.gpadlhdr.range_count = cpu_to_le16 ( 1 );
+ gpadlhdr.range.len = cpu_to_le32 ( len );
+ gpadlhdr.range.offset = cpu_to_le32 ( addr & ( PAGE_SIZE - 1 ) );
+ for ( i = 0 ; i < pfn_count ; i++ )
+ gpadlhdr.pfn[i] = ( ( addr / PAGE_SIZE ) + i );
+
+ /* Post message */
+ if ( ( rc = vmbus_post_message ( hv, &gpadlhdr.gpadlhdr.header,
+ sizeof ( gpadlhdr ) ) ) != 0 )
+ return rc;
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ return rc;
+
+ /* Check response */
+ if ( created->header.type != cpu_to_le32 ( VMBUS_GPADL_CREATED ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected GPADL response type %d\n",
+ vmdev->dev.name, le32_to_cpu ( created->header.type ) );
+ return -EPROTO;
+ }
+ if ( created->channel != cpu_to_le32 ( vmdev->channel ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected GPADL channel %d\n",
+ vmdev->dev.name, le32_to_cpu ( created->channel ) );
+ return -EPROTO;
+ }
+ if ( created->gpadl != cpu_to_le32 ( gpadl ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected GPADL ID %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( created->gpadl ) );
+ return -EPROTO;
+ }
+ if ( created->status != 0 ) {
+ DBGC ( vmdev, "VMBUS %s GPADL creation failed: %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( created->status ) );
+ return -EPROTO;
+ }
+
+ DBGC ( vmdev, "VMBUS %s GPADL %#08x is [%08lx,%08lx)\n",
+ vmdev->dev.name, gpadl, addr, ( addr + len ) );
+ return gpadl;
+}
+
+/**
+ * Tear down GPA descriptor list
+ *
+ * @v vmdev VMBus device
+ * @v gpadl GPADL ID
+ * @ret rc Return status code
+ */
+int vmbus_gpadl_teardown ( struct vmbus_device *vmdev, unsigned int gpadl ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus *vmbus = hv->vmbus;
+ struct vmbus_gpadl_teardown teardown;
+ const struct vmbus_gpadl_torndown *torndown = &vmbus->message->torndown;
+ int rc;
+
+ /* Construct message */
+ memset ( &teardown, 0, sizeof ( teardown ) );
+ teardown.header.type = cpu_to_le32 ( VMBUS_GPADL_TEARDOWN );
+ teardown.channel = cpu_to_le32 ( vmdev->channel );
+ teardown.gpadl = cpu_to_le32 ( gpadl );
+
+ /* Post message */
+ if ( ( rc = vmbus_post_message ( hv, &teardown.header,
+ sizeof ( teardown ) ) ) != 0 )
+ return rc;
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ return rc;
+
+ /* Check response */
+ if ( torndown->header.type != cpu_to_le32 ( VMBUS_GPADL_TORNDOWN ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected GPADL response type %d\n",
+ vmdev->dev.name, le32_to_cpu ( torndown->header.type ) );
+ return -EPROTO;
+ }
+ if ( torndown->gpadl != cpu_to_le32 ( gpadl ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected GPADL ID %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( torndown->gpadl ) );
+ return -EPROTO;
+ }
+
+ return 0;
+}
+
+/**
+ * Open VMBus channel
+ *
+ * @v vmdev VMBus device
+ * @v op Channel operations
+ * @v out_len Outbound ring buffer length
+ * @v in_len Inbound ring buffer length
+ * @v mtu Maximum expected data packet length (including headers)
+ * @ret rc Return status code
+ *
+ * Both outbound and inbound ring buffer lengths must be a power of
+ * two and a multiple of PAGE_SIZE. The requirement to be a power of
+ * two is a policy decision taken to simplify the ring buffer indexing
+ * logic.
+ */
+int vmbus_open ( struct vmbus_device *vmdev,
+ struct vmbus_channel_operations *op,
+ size_t out_len, size_t in_len, size_t mtu ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus *vmbus = hv->vmbus;
+ struct vmbus_open_channel open;
+ const struct vmbus_open_channel_result *opened =
+ &vmbus->message->opened;
+ size_t len;
+ void *ring;
+ void *packet;
+ int gpadl;
+ uint32_t open_id;
+ int rc;
+
+ /* Sanity checks */
+ assert ( ( out_len % PAGE_SIZE ) == 0 );
+ assert ( ( out_len & ( out_len - 1 ) ) == 0 );
+ assert ( ( in_len % PAGE_SIZE ) == 0 );
+ assert ( ( in_len & ( in_len - 1 ) ) == 0 );
+ assert ( mtu >= ( sizeof ( struct vmbus_packet_header ) +
+ sizeof ( struct vmbus_packet_footer ) ) );
+
+ /* Allocate packet buffer */
+ packet = malloc ( mtu );
+ if ( ! packet ) {
+ rc = -ENOMEM;
+ goto err_alloc_packet;
+ }
+
+ /* Allocate ring buffer */
+ len = ( sizeof ( *vmdev->out ) + out_len +
+ sizeof ( *vmdev->in ) + in_len );
+ assert ( ( len % PAGE_SIZE ) == 0 );
+ ring = malloc_dma ( len, PAGE_SIZE );
+ if ( ! ring ) {
+ rc = -ENOMEM;
+ goto err_alloc_ring;
+ }
+ memset ( ring, 0, len );
+
+ /* Establish GPADL for ring buffer */
+ gpadl = vmbus_establish_gpadl ( vmdev, virt_to_user ( ring ), len );
+ if ( gpadl < 0 ) {
+ rc = gpadl;
+ goto err_establish;
+ }
+
+ /* Construct message */
+ memset ( &open, 0, sizeof ( open ) );
+ open.header.type = cpu_to_le32 ( VMBUS_OPEN_CHANNEL );
+ open.channel = cpu_to_le32 ( vmdev->channel );
+ open_id = random();
+ open.id = open_id; /* Opaque random value: endianness irrelevant */
+ open.gpadl = cpu_to_le32 ( gpadl );
+ open.out_pages = ( ( sizeof ( *vmdev->out ) / PAGE_SIZE ) +
+ ( out_len / PAGE_SIZE ) );
+
+ /* Post message */
+ if ( ( rc = vmbus_post_message ( hv, &open.header,
+ sizeof ( open ) ) ) != 0 )
+ return rc;
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ return rc;
+
+ /* Check response */
+ if ( opened->header.type != cpu_to_le32 ( VMBUS_OPEN_CHANNEL_RESULT ) ){
+ DBGC ( vmdev, "VMBUS %s unexpected open response type %d\n",
+ vmdev->dev.name, le32_to_cpu ( opened->header.type ) );
+ return -EPROTO;
+ }
+ if ( opened->channel != cpu_to_le32 ( vmdev->channel ) ) {
+ DBGC ( vmdev, "VMBUS %s unexpected opened channel %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( opened->channel ) );
+ return -EPROTO;
+ }
+ if ( opened->id != open_id /* Non-endian */ ) {
+ DBGC ( vmdev, "VMBUS %s unexpected open ID %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( opened->id ) );
+ return -EPROTO;
+ }
+ if ( opened->status != 0 ) {
+ DBGC ( vmdev, "VMBUS %s open failed: %#08x\n",
+ vmdev->dev.name, le32_to_cpu ( opened->status ) );
+ return -EPROTO;
+ }
+
+ /* Store channel parameters */
+ vmdev->out_len = out_len;
+ vmdev->in_len = in_len;
+ vmdev->out = ring;
+ vmdev->in = ( ring + sizeof ( *vmdev->out ) + out_len );
+ vmdev->gpadl = gpadl;
+ vmdev->op = op;
+ vmdev->mtu = mtu;
+ vmdev->packet = packet;
+
+ DBGC ( vmdev, "VMBUS %s channel GPADL %#08x ring "
+ "[%#08lx,%#08lx,%#08lx)\n", vmdev->dev.name, vmdev->gpadl,
+ virt_to_phys ( vmdev->out ), virt_to_phys ( vmdev->in ),
+ ( virt_to_phys ( vmdev->out ) + len ) );
+ return 0;
+
+ vmbus_gpadl_teardown ( vmdev, vmdev->gpadl );
+ err_establish:
+ free_dma ( ring, len );
+ err_alloc_ring:
+ free ( packet );
+ err_alloc_packet:
+ return rc;
+}
+
+/**
+ * Close VMBus channel
+ *
+ * @v vmdev VMBus device
+ */
+void vmbus_close ( struct vmbus_device *vmdev ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus_close_channel close;
+ size_t len;
+ int rc;
+
+ /* Construct message */
+ memset ( &close, 0, sizeof ( close ) );
+ close.header.type = cpu_to_le32 ( VMBUS_CLOSE_CHANNEL );
+ close.channel = cpu_to_le32 ( vmdev->channel );
+
+ /* Post message */
+ if ( ( rc = vmbus_post_message ( hv, &close.header,
+ sizeof ( close ) ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s failed to close: %s\n",
+ vmdev->dev.name, strerror ( rc ) );
+ /* Continue to attempt to tear down GPADL, so that our
+ * memory is no longer accessible by the remote VM.
+ */
+ }
+
+ /* Tear down GPADL */
+ if ( ( rc = vmbus_gpadl_teardown ( vmdev,
+ vmdev->gpadl ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s failed to tear down channel GPADL: "
+ "%s\n", vmdev->dev.name, strerror ( rc ) );
+ /* We can't prevent the remote VM from continuing to
+ * access this memory, so leak it.
+ */
+ return;
+ }
+
+ /* Free ring buffer */
+ len = ( sizeof ( *vmdev->out ) + vmdev->out_len +
+ sizeof ( *vmdev->in ) + vmdev->in_len );
+ free_dma ( vmdev->out, len );
+ vmdev->out = NULL;
+ vmdev->in = NULL;
+
+ /* Free packet buffer */
+ free ( vmdev->packet );
+ vmdev->packet = NULL;
+
+ DBGC ( vmdev, "VMBUS %s closed\n", vmdev->dev.name );
+}
+
+/**
+ * Signal channel via monitor page
+ *
+ * @v vmdev VMBus device
+ */
+static void vmbus_signal_monitor ( struct vmbus_device *vmdev ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus *vmbus = hv->vmbus;
+ struct hv_monitor_trigger *trigger;
+ unsigned int group;
+ unsigned int bit;
+
+ /* Set bit in monitor trigger group */
+ group = ( vmdev->monitor / ( 8 * sizeof ( trigger->pending ) ));
+ bit = ( vmdev->monitor % ( 8 * sizeof ( trigger->pending ) ) );
+ trigger = &vmbus->monitor_out->trigger[group];
+ hv_set_bit ( trigger, bit );
+}
+
+/**
+ * Signal channel via hypervisor event
+ *
+ * @v vmdev VMBus device
+ */
+static void vmbus_signal_event ( struct vmbus_device *vmdev ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ int rc;
+
+ /* Signal hypervisor event */
+ if ( ( rc = hv_signal_event ( hv, VMBUS_EVENT_ID, 0 ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not signal event: %s\n",
+ vmdev->dev.name, strerror ( rc ) );
+ return;
+ }
+}
+
+/**
+ * Fill outbound ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v prod Producer index
+ * @v data Data
+ * @v len Length
+ * @ret prod New producer index
+ *
+ * The caller must ensure that there is sufficient space in the ring
+ * buffer.
+ */
+static size_t vmbus_produce ( struct vmbus_device *vmdev, size_t prod,
+ const void *data, size_t len ) {
+ size_t first;
+ size_t second;
+
+ /* Determine fragment lengths */
+ first = ( vmdev->out_len - prod );
+ if ( first > len )
+ first = len;
+ second = ( len - first );
+
+ /* Copy fragment(s) */
+ memcpy ( &vmdev->out->data[prod], data, first );
+ if ( second )
+ memcpy ( &vmdev->out->data[0], ( data + first ), second );
+
+ return ( ( prod + len ) & ( vmdev->out_len - 1 ) );
+}
+
+/**
+ * Consume inbound ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v cons Consumer index
+ * @v data Data buffer, or NULL
+ * @v len Length to consume
+ * @ret cons New consumer index
+ */
+static size_t vmbus_consume ( struct vmbus_device *vmdev, size_t cons,
+ void *data, size_t len ) {
+ size_t first;
+ size_t second;
+
+ /* Determine fragment lengths */
+ first = ( vmdev->in_len - cons );
+ if ( first > len )
+ first = len;
+ second = ( len - first );
+
+ /* Copy fragment(s) */
+ memcpy ( data, &vmdev->in->data[cons], first );
+ if ( second )
+ memcpy ( ( data + first ), &vmdev->in->data[0], second );
+
+ return ( ( cons + len ) & ( vmdev->in_len - 1 ) );
+}
+
+/**
+ * Send packet via ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v header Packet header
+ * @v data Data
+ * @v len Length of data
+ * @ret rc Return status code
+ *
+ * Send a packet via the outbound ring buffer. All fields in the
+ * packet header must be filled in, with the exception of the total
+ * packet length.
+ */
+static int vmbus_send ( struct vmbus_device *vmdev,
+ struct vmbus_packet_header *header,
+ const void *data, size_t len ) {
+ struct hv_hypervisor *hv = vmdev->hv;
+ struct vmbus *vmbus = hv->vmbus;
+ static uint8_t padding[ 8 - 1 ];
+ struct vmbus_packet_footer footer;
+ size_t header_len;
+ size_t pad_len;
+ size_t footer_len;
+ size_t ring_len;
+ size_t cons;
+ size_t prod;
+ size_t old_prod;
+ size_t fill;
+
+ /* Sanity check */
+ assert ( vmdev->out != NULL );
+
+ /* Calculate lengths */
+ header_len = ( le16_to_cpu ( header->hdr_qlen ) * 8 );
+ pad_len = ( ( -len ) & ( 8 - 1 ) );
+ footer_len = sizeof ( footer );
+ ring_len = ( header_len + len + pad_len + footer_len );
+
+ /* Check that we have enough room in the outbound ring buffer */
+ cons = le32_to_cpu ( vmdev->out->cons );
+ prod = le32_to_cpu ( vmdev->out->prod );
+ old_prod = prod;
+ fill = ( ( prod - cons ) & ( vmdev->out_len - 1 ) );
+ if ( ( fill + ring_len ) >= vmdev->out_len ) {
+ DBGC ( vmdev, "VMBUS %s ring buffer full\n", vmdev->dev.name );
+ return -ENOBUFS;
+ }
+
+ /* Complete header */
+ header->qlen = cpu_to_le16 ( ( ring_len - footer_len ) / 8 );
+
+ /* Construct footer */
+ footer.reserved = 0;
+ footer.prod = vmdev->out->prod;
+
+ /* Copy packet to buffer */
+ DBGC2 ( vmdev, "VMBUS %s sending:\n", vmdev->dev.name );
+ DBGC2_HDA ( vmdev, prod, header, header_len );
+ prod = vmbus_produce ( vmdev, prod, header, header_len );
+ DBGC2_HDA ( vmdev, prod, data, len );
+ prod = vmbus_produce ( vmdev, prod, data, len );
+ prod = vmbus_produce ( vmdev, prod, padding, pad_len );
+ DBGC2_HDA ( vmdev, prod, &footer, sizeof ( footer ) );
+ prod = vmbus_produce ( vmdev, prod, &footer, sizeof ( footer ) );
+ assert ( ( ( prod - old_prod ) & ( vmdev->out_len - 1 ) ) == ring_len );
+
+ /* Update producer index */
+ wmb();
+ vmdev->out->prod = cpu_to_le32 ( prod );
+
+ /* Return if we do not need to signal the host. This follows
+ * the logic of hv_need_to_signal() in the Linux driver.
+ */
+ mb();
+ if ( vmdev->out->intr_mask )
+ return 0;
+ rmb();
+ cons = le32_to_cpu ( vmdev->out->cons );
+ if ( cons != old_prod )
+ return 0;
+
+ /* Set channel bit in interrupt page */
+ hv_set_bit ( vmbus->intr->out, vmdev->channel );
+
+ /* Signal the host */
+ vmdev->signal ( vmdev );
+
+ return 0;
+}
+
+/**
+ * Send control packet via ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v xid Transaction ID (or zero to not request completion)
+ * @v data Data
+ * @v len Length of data
+ * @ret rc Return status code
+ *
+ * Send data using a VMBUS_DATA_INBAND packet.
+ */
+int vmbus_send_control ( struct vmbus_device *vmdev, uint64_t xid,
+ const void *data, size_t len ) {
+ struct vmbus_packet_header *header = vmdev->packet;
+
+ /* Construct header in packet buffer */
+ assert ( header != NULL );
+ header->type = cpu_to_le16 ( VMBUS_DATA_INBAND );
+ header->hdr_qlen = cpu_to_le16 ( sizeof ( *header ) / 8 );
+ header->flags = ( xid ?
+ cpu_to_le16 ( VMBUS_COMPLETION_REQUESTED ) : 0 );
+ header->xid = xid; /* Non-endian */
+
+ return vmbus_send ( vmdev, header, data, len );
+}
+
+/**
+ * Send data packet via ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v xid Transaction ID
+ * @v data Data
+ * @v len Length of data
+ * @v iobuf I/O buffer
+ * @ret rc Return status code
+ *
+ * Send data using a VMBUS_DATA_GPA_DIRECT packet. The caller is
+ * responsible for ensuring that the I/O buffer remains untouched
+ * until the corresponding completion has been received.
+ */
+int vmbus_send_data ( struct vmbus_device *vmdev, uint64_t xid,
+ const void *data, size_t len, struct io_buffer *iobuf ) {
+ physaddr_t addr = virt_to_phys ( iobuf->data );
+ unsigned int pfn_count = hv_pfn_count ( addr, iob_len ( iobuf ) );
+ struct {
+ struct vmbus_gpa_direct_header gpa;
+ struct vmbus_gpa_range range;
+ uint64_t pfn[pfn_count];
+ } __attribute__ (( packed )) *header = vmdev->packet;
+ unsigned int i;
+
+ /* Sanity check */
+ assert ( header != NULL );
+ assert ( sizeof ( *header ) <= vmdev->mtu );
+
+ /* Construct header in packet buffer */
+ header->gpa.header.type = cpu_to_le16 ( VMBUS_DATA_GPA_DIRECT );
+ header->gpa.header.hdr_qlen = cpu_to_le16 ( sizeof ( *header ) / 8 );
+ header->gpa.header.flags = cpu_to_le16 ( VMBUS_COMPLETION_REQUESTED );
+ header->gpa.header.xid = xid; /* Non-endian */
+ header->gpa.range_count = 1;
+ header->range.len = cpu_to_le32 ( iob_len ( iobuf ) );
+ header->range.offset = cpu_to_le32 ( addr & ( PAGE_SIZE - 1 ) );
+ for ( i = 0 ; i < pfn_count ; i++ )
+ header->pfn[i] = ( ( addr / PAGE_SIZE ) + i );
+
+ return vmbus_send ( vmdev, &header->gpa.header, data, len );
+}
+
+/**
+ * Send completion packet via ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v xid Transaction ID
+ * @v data Data
+ * @v len Length of data
+ * @ret rc Return status code
+ *
+ * Send data using a VMBUS_COMPLETION packet.
+ */
+int vmbus_send_completion ( struct vmbus_device *vmdev, uint64_t xid,
+ const void *data, size_t len ) {
+ struct vmbus_packet_header *header = vmdev->packet;
+
+ /* Construct header in packet buffer */
+ assert ( header != NULL );
+ header->type = cpu_to_le16 ( VMBUS_COMPLETION );
+ header->hdr_qlen = cpu_to_le16 ( sizeof ( *header ) / 8 );
+ header->flags = 0;
+ header->xid = xid; /* Non-endian */
+
+ return vmbus_send ( vmdev, header, data, len );
+}
+
+/**
+ * Send cancellation packet via ring buffer
+ *
+ * @v vmdev VMBus device
+ * @v xid Transaction ID
+ * @ret rc Return status code
+ *
+ * Send data using a VMBUS_CANCELLATION packet.
+ */
+int vmbus_send_cancellation ( struct vmbus_device *vmdev, uint64_t xid ) {
+ struct vmbus_packet_header *header = vmdev->packet;
+
+ /* Construct header in packet buffer */
+ assert ( header != NULL );
+ header->type = cpu_to_le16 ( VMBUS_CANCELLATION );
+ header->hdr_qlen = cpu_to_le16 ( sizeof ( *header ) / 8 );
+ header->flags = 0;
+ header->xid = xid; /* Non-endian */
+
+ return vmbus_send ( vmdev, header, NULL, 0 );
+}
+
+/**
+ * Get transfer page set from pageset ID
+ *
+ * @v vmdev VMBus device
+ * @v pageset Page set ID (in protocol byte order)
+ * @ret pages Page set, or NULL if not found
+ */
+static struct vmbus_xfer_pages * vmbus_xfer_pages ( struct vmbus_device *vmdev,
+ uint16_t pageset ) {
+ struct vmbus_xfer_pages *pages;
+
+ /* Locate page set */
+ list_for_each_entry ( pages, &vmdev->pages, list ) {
+ if ( pages->pageset == pageset )
+ return pages;
+ }
+
+ DBGC ( vmdev, "VMBUS %s unrecognised page set ID %#04x\n",
+ vmdev->dev.name, le16_to_cpu ( pageset ) );
+ return NULL;
+}
+
+/**
+ * Construct I/O buffer list from transfer pages
+ *
+ * @v vmdev VMBus device
+ * @v header Transfer page header
+ * @v list I/O buffer list to populate
+ * @ret rc Return status code
+ */
+static int vmbus_xfer_page_iobufs ( struct vmbus_device *vmdev,
+ struct vmbus_packet_header *header,
+ struct list_head *list ) {
+ struct vmbus_xfer_page_header *page_header =
+ container_of ( header, struct vmbus_xfer_page_header, header );
+ struct vmbus_xfer_pages *pages;
+ struct io_buffer *iobuf;
+ struct io_buffer *tmp;
+ size_t len;
+ size_t offset;
+ unsigned int range_count;
+ unsigned int i;
+ int rc;
+
+ /* Sanity check */
+ assert ( header->type == cpu_to_le16 ( VMBUS_DATA_XFER_PAGES ) );
+
+ /* Locate page set */
+ pages = vmbus_xfer_pages ( vmdev, page_header->pageset );
+ if ( ! pages ) {
+ rc = -ENOENT;
+ goto err_pages;
+ }
+
+ /* Allocate and populate I/O buffers */
+ range_count = le32_to_cpu ( page_header->range_count );
+ for ( i = 0 ; i < range_count ; i++ ) {
+
+ /* Parse header */
+ len = le32_to_cpu ( page_header->range[i].len );
+ offset = le32_to_cpu ( page_header->range[i].offset );
+
+ /* Allocate I/O buffer */
+ iobuf = alloc_iob ( len );
+ if ( ! iobuf ) {
+ DBGC ( vmdev, "VMBUS %s could not allocate %zd-byte "
+ "I/O buffer\n", vmdev->dev.name, len );
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+
+ /* Add I/O buffer to list */
+ list_add ( &iobuf->list, list );
+
+ /* Populate I/O buffer */
+ if ( ( rc = pages->op->copy ( pages, iob_put ( iobuf, len ),
+ offset, len ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not populate I/O buffer "
+ "range [%zd,%zd): %s\n",
+ vmdev->dev.name, offset, len, strerror ( rc ) );
+ goto err_copy;
+ }
+ }
+
+ return 0;
+
+ err_copy:
+ err_alloc:
+ list_for_each_entry_safe ( iobuf, tmp, list, list ) {
+ list_del ( &iobuf->list );
+ free_iob ( iobuf );
+ }
+ err_pages:
+ return rc;
+}
+
+/**
+ * Poll ring buffer
+ *
+ * @v vmdev VMBus device
+ * @ret rc Return status code
+ */
+int vmbus_poll ( struct vmbus_device *vmdev ) {
+ struct vmbus_packet_header *header = vmdev->packet;
+ struct list_head list;
+ void *data;
+ size_t header_len;
+ size_t len;
+ size_t footer_len;
+ size_t ring_len;
+ size_t cons;
+ size_t old_cons;
+ uint64_t xid;
+ int rc;
+
+ /* Sanity checks */
+ assert ( vmdev->packet != NULL );
+ assert ( vmdev->in != NULL );
+
+ /* Return immediately if buffer is empty */
+ if ( ! vmbus_has_data ( vmdev ) )
+ return 0;
+ cons = le32_to_cpu ( vmdev->in->cons );
+ old_cons = cons;
+
+ /* Consume (start of) header */
+ cons = vmbus_consume ( vmdev, cons, header, sizeof ( *header ) );
+
+ /* Parse and sanity check header */
+ header_len = ( le16_to_cpu ( header->hdr_qlen ) * 8 );
+ if ( header_len < sizeof ( *header ) ) {
+ DBGC ( vmdev, "VMBUS %s received underlength header (%zd "
+ "bytes)\n", vmdev->dev.name, header_len );
+ return -EINVAL;
+ }
+ len = ( ( le16_to_cpu ( header->qlen ) * 8 ) - header_len );
+ footer_len = sizeof ( struct vmbus_packet_footer );
+ ring_len = ( header_len + len + footer_len );
+ if ( ring_len > vmdev->mtu ) {
+ DBGC ( vmdev, "VMBUS %s received overlength packet (%zd "
+ "bytes)\n", vmdev->dev.name, ring_len );
+ return -ERANGE;
+ }
+ xid = le64_to_cpu ( header->xid );
+
+ /* Consume remainder of packet */
+ cons = vmbus_consume ( vmdev, cons,
+ ( ( ( void * ) header ) + sizeof ( *header ) ),
+ ( ring_len - sizeof ( *header ) ) );
+ DBGC2 ( vmdev, "VMBUS %s received:\n", vmdev->dev.name );
+ DBGC2_HDA ( vmdev, old_cons, header, ring_len );
+ assert ( ( ( cons - old_cons ) & ( vmdev->in_len - 1 ) ) == ring_len );
+
+ /* Allocate I/O buffers, if applicable */
+ INIT_LIST_HEAD ( &list );
+ if ( header->type == cpu_to_le16 ( VMBUS_DATA_XFER_PAGES ) ) {
+ if ( ( rc = vmbus_xfer_page_iobufs ( vmdev, header,
+ &list ) ) != 0 )
+ return rc;
+ }
+
+ /* Update producer index */
+ rmb();
+ vmdev->in->cons = cpu_to_le32 ( cons );
+
+ /* Handle packet */
+ data = ( ( ( void * ) header ) + header_len );
+ switch ( header->type ) {
+
+ case cpu_to_le16 ( VMBUS_DATA_INBAND ) :
+ if ( ( rc = vmdev->op->recv_control ( vmdev, xid, data,
+ len ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not handle control "
+ "packet: %s\n",
+ vmdev->dev.name, strerror ( rc ) );
+ return rc;
+ }
+ break;
+
+ case cpu_to_le16 ( VMBUS_DATA_XFER_PAGES ) :
+ if ( ( rc = vmdev->op->recv_data ( vmdev, xid, data, len,
+ &list ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not handle data packet: "
+ "%s\n", vmdev->dev.name, strerror ( rc ) );
+ return rc;
+ }
+ break;
+
+ case cpu_to_le16 ( VMBUS_COMPLETION ) :
+ if ( ( rc = vmdev->op->recv_completion ( vmdev, xid, data,
+ len ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not handle completion: "
+ "%s\n", vmdev->dev.name, strerror ( rc ) );
+ return rc;
+ }
+ break;
+
+ case cpu_to_le16 ( VMBUS_CANCELLATION ) :
+ if ( ( rc = vmdev->op->recv_cancellation ( vmdev, xid ) ) != 0){
+ DBGC ( vmdev, "VMBUS %s could not handle cancellation: "
+ "%s\n", vmdev->dev.name, strerror ( rc ) );
+ return rc;
+ }
+ break;
+
+ default:
+ DBGC ( vmdev, "VMBUS %s unknown packet type %d\n",
+ vmdev->dev.name, le16_to_cpu ( header->type ) );
+ return -ENOTSUP;
+ }
+
+ return 0;
+}
+
+/**
+ * Dump channel status (for debugging)
+ *
+ * @v vmdev VMBus device
+ */
+void vmbus_dump_channel ( struct vmbus_device *vmdev ) {
+ size_t out_prod = le32_to_cpu ( vmdev->out->prod );
+ size_t out_cons = le32_to_cpu ( vmdev->out->cons );
+ size_t in_prod = le32_to_cpu ( vmdev->in->prod );
+ size_t in_cons = le32_to_cpu ( vmdev->in->cons );
+ size_t in_len;
+ size_t first;
+ size_t second;
+
+ /* Dump ring status */
+ DBGC ( vmdev, "VMBUS %s out %03zx:%03zx%s in %03zx:%03zx%s\n",
+ vmdev->dev.name, out_prod, out_cons,
+ ( vmdev->out->intr_mask ? "(m)" : "" ), in_prod, in_cons,
+ ( vmdev->in->intr_mask ? "(m)" : "" ) );
+
+ /* Dump inbound ring contents, if any */
+ if ( in_prod != in_cons ) {
+ in_len = ( ( in_prod - in_cons ) &
+ ( vmdev->in_len - 1 ) );
+ first = ( vmdev->in_len - in_cons );
+ if ( first > in_len )
+ first = in_len;
+ second = ( in_len - first );
+ DBGC_HDA ( vmdev, in_cons, &vmdev->in->data[in_cons], first );
+ DBGC_HDA ( vmdev, 0, &vmdev->in->data[0], second );
+ }
+}
+
+/**
+ * Find driver for VMBus device
+ *
+ * @v vmdev VMBus device
+ * @ret driver Driver, or NULL
+ */
+static struct vmbus_driver * vmbus_find_driver ( const union uuid *type ) {
+ struct vmbus_driver *vmdrv;
+
+ for_each_table_entry ( vmdrv, VMBUS_DRIVERS ) {
+ if ( memcmp ( &vmdrv->type, type, sizeof ( *type ) ) == 0 )
+ return vmdrv;
+ }
+ return NULL;
+}
+
+/**
+ * Probe channels
+ *
+ * @v hv Hyper-V hypervisor
+ * @v parent Parent device
+ * @ret rc Return status code
+ */
+static int vmbus_probe_channels ( struct hv_hypervisor *hv,
+ struct device *parent ) {
+ struct vmbus *vmbus = hv->vmbus;
+ const struct vmbus_message_header *header = &vmbus->message->header;
+ const struct vmbus_offer_channel *offer = &vmbus->message->offer;
+ const union uuid *type;
+ struct vmbus_driver *driver;
+ struct vmbus_device *vmdev;
+ struct vmbus_device *tmp;
+ unsigned int channel;
+ int rc;
+
+ /* Post message */
+ if ( ( rc = vmbus_post_empty_message ( hv, VMBUS_REQUEST_OFFERS ) ) !=0)
+ goto err_post_message;
+
+ /* Collect responses */
+ while ( 1 ) {
+
+ /* Wait for response */
+ if ( ( rc = vmbus_wait_for_message ( hv ) ) != 0 )
+ goto err_wait_for_message;
+
+ /* Handle response */
+ if ( header->type == cpu_to_le32 ( VMBUS_OFFER_CHANNEL ) ) {
+
+ /* Parse offer */
+ type = &offer->type;
+ channel = le32_to_cpu ( offer->channel );
+ DBGC2 ( vmbus, "VMBUS %p offer %d type %s",
+ vmbus, channel, uuid_ntoa ( type ) );
+ if ( offer->monitored )
+ DBGC2 ( vmbus, " monitor %d", offer->monitor );
+ DBGC2 ( vmbus, "\n" );
+
+ /* Look for a driver */
+ driver = vmbus_find_driver ( type );
+ if ( ! driver ) {
+ DBGC2 ( vmbus, "VMBUS %p has no driver for "
+ "type %s\n", vmbus, uuid_ntoa ( type ));
+ /* Not a fatal error */
+ continue;
+ }
+
+ /* Allocate and initialise device */
+ vmdev = zalloc ( sizeof ( *vmdev ) );
+ if ( ! vmdev ) {
+ rc = -ENOMEM;
+ goto err_alloc_vmdev;
+ }
+ snprintf ( vmdev->dev.name, sizeof ( vmdev->dev.name ),
+ "vmbus:%02x", channel );
+ vmdev->dev.desc.bus_type = BUS_TYPE_HV;
+ INIT_LIST_HEAD ( &vmdev->dev.children );
+ list_add_tail ( &vmdev->dev.siblings,
+ &parent->children );
+ vmdev->dev.parent = parent;
+ vmdev->hv = hv;
+ vmdev->channel = channel;
+ vmdev->monitor = offer->monitor;
+ vmdev->signal = ( offer->monitored ?
+ vmbus_signal_monitor :
+ vmbus_signal_event );
+ INIT_LIST_HEAD ( &vmdev->pages );
+ vmdev->driver = driver;
+ vmdev->dev.driver_name = driver->name;
+ DBGC ( vmdev, "VMBUS %s has driver \"%s\"\n",
+ vmdev->dev.name, vmdev->driver->name );
+
+ } else if ( header->type ==
+ cpu_to_le32 ( VMBUS_ALL_OFFERS_DELIVERED ) ) {
+
+ break;
+
+ } else {
+ DBGC ( vmbus, "VMBUS %p unexpected offer response type "
+ "%d\n", vmbus, le32_to_cpu ( header->type ) );
+ rc = -EPROTO;
+ goto err_unexpected_offer;
+ }
+ }
+
+ /* Probe all devices. We do this only after completing
+ * enumeration since devices will need to send and receive
+ * VMBus messages.
+ */
+ list_for_each_entry ( vmdev, &parent->children, dev.siblings ) {
+ if ( ( rc = vmdev->driver->probe ( vmdev ) ) != 0 ) {
+ DBGC ( vmdev, "VMBUS %s could not probe: %s\n",
+ vmdev->dev.name, strerror ( rc ) );
+ goto err_probe;
+ }
+ }
+
+ return 0;
+
+ err_probe:
+ /* Remove driver from each device that was already probed */
+ list_for_each_entry_continue_reverse ( vmdev, &parent->children,
+ dev.siblings ) {
+ vmdev->driver->remove ( vmdev );
+ }
+ err_unexpected_offer:
+ err_alloc_vmdev:
+ err_wait_for_message:
+ /* Free any devices allocated (but potentially not yet probed) */
+ list_for_each_entry_safe ( vmdev, tmp, &parent->children,
+ dev.siblings ) {
+ list_del ( &vmdev->dev.siblings );
+ free ( vmdev );
+ }
+ err_post_message:
+ return rc;
+}
+
+/**
+ * Remove channels
+ *
+ * @v hv Hyper-V hypervisor
+ * @v parent Parent device
+ */
+static void vmbus_remove_channels ( struct hv_hypervisor *hv __unused,
+ struct device *parent ) {
+ struct vmbus_device *vmdev;
+ struct vmbus_device *tmp;
+
+ /* Remove devices */
+ list_for_each_entry_safe ( vmdev, tmp, &parent->children,
+ dev.siblings ) {
+ vmdev->driver->remove ( vmdev );
+ assert ( list_empty ( &vmdev->dev.children ) );
+ assert ( vmdev->out == NULL );
+ assert ( vmdev->in == NULL );
+ assert ( vmdev->packet == NULL );
+ assert ( list_empty ( &vmdev->pages ) );
+ list_del ( &vmdev->dev.siblings );
+ free ( vmdev );
+ }
+}
+
+/**
+ * Probe Hyper-V virtual machine bus
+ *
+ * @v hv Hyper-V hypervisor
+ * @v parent Parent device
+ * @ret rc Return status code
+ */
+int vmbus_probe ( struct hv_hypervisor *hv, struct device *parent ) {
+ struct vmbus *vmbus;
+ int rc;
+
+ /* Allocate and initialise structure */
+ vmbus = zalloc ( sizeof ( *vmbus ) );
+ if ( ! vmbus ) {
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+ hv->vmbus = vmbus;
+
+ /* Initialise message buffer pointer
+ *
+ * We use a pointer to the fixed-size Hyper-V received message
+ * buffer. This allows us to access fields within received
+ * messages without first checking the message size: any
+ * fields beyond the end of the message will read as zero.
+ */
+ vmbus->message = ( ( void * ) hv->message->received.data );
+ assert ( sizeof ( *vmbus->message ) <=
+ sizeof ( hv->message->received.data ) );
+
+ /* Allocate interrupt and monitor pages */
+ if ( ( rc = hv_alloc_pages ( hv, &vmbus->intr, &vmbus->monitor_in,
+ &vmbus->monitor_out, NULL ) ) != 0 )
+ goto err_alloc_pages;
+
+ /* Enable message interrupt */
+ hv_enable_sint ( hv, VMBUS_MESSAGE_SINT );
+
+ /* Negotiate protocol version */
+ if ( ( rc = vmbus_negotiate_version ( hv ) ) != 0 )
+ goto err_negotiate_version;
+
+ /* Enumerate channels */
+ if ( ( rc = vmbus_probe_channels ( hv, parent ) ) != 0 )
+ goto err_probe_channels;
+
+ return 0;
+
+ vmbus_remove_channels ( hv, parent );
+ err_probe_channels:
+ vmbus_unload ( hv );
+ err_negotiate_version:
+ hv_disable_sint ( hv, VMBUS_MESSAGE_SINT );
+ hv_free_pages ( hv, vmbus->intr, vmbus->monitor_in, vmbus->monitor_out,
+ NULL );
+ err_alloc_pages:
+ free ( vmbus );
+ err_alloc:
+ return rc;
+}
+
+/**
+ * Remove Hyper-V virtual machine bus
+ *
+ * @v hv Hyper-V hypervisor
+ * @v parent Parent device
+ */
+void vmbus_remove ( struct hv_hypervisor *hv, struct device *parent ) {
+ struct vmbus *vmbus = hv->vmbus;
+
+ vmbus_remove_channels ( hv, parent );
+ vmbus_unload ( hv );
+ hv_disable_sint ( hv, VMBUS_MESSAGE_SINT );
+ hv_free_pages ( hv, vmbus->intr, vmbus->monitor_in, vmbus->monitor_out,
+ NULL );
+ free ( vmbus );
+}
Code Review / kvmfornfv.git / blobdiff