vhost, pc: fixes for 2.5

Fixes all over the place.
 
 This also re-enables a test we disabled in 2.5 cycle
 now that there's a way not to get a warning from it.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

vhost, pc: fixes for 2.5

Fixes all over the place.

This also re-enables a test we disabled in 2.5 cycle
now that there's a way not to get a warning from it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Thu 19 Nov 2015 13:27:43 GMT using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"

* remotes/mst/tags/for_upstream:
  exec: silence hugetlbfs warning under qtest
  tests: re-enable vhost-user-test
  acpi: fix buffer overrun on migration
  vhost-user: fix log size
  vhost-user: ignore qemu-only features
  specs/vhost-user: fix spec to match reality
  tests/vhost-user-bridge: implement logging of dirty pages
  i440fx: print an error message if user tries to enable iommu
  q35: Check propery to determine if iommu is set
  vhost-user: start/stop all rings
  vhost-user: print original request on error
  vhost-user-test: support VHOST_USER_SET_VRING_ENABLE
  vhost-user: update spec description
  vhost: don't send RESET_OWNER at stop
  vhost: let SET_VRING_ENABLE message depends on protocol feature

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

configure

@@ -5681,6 +5681,7 @@ case "$target_name" in
       echo "CONFIG_KVM=y" >> $config_target_mak
       if test "$vhost_net" = "yes" ; then
         echo "CONFIG_VHOST_NET=y" >> $config_target_mak
+        echo "CONFIG_VHOST_NET_TEST_$target_name=y" >> $config_host_mak
       fi
     fi
 esac

docs/specs/vhost-user.txt

@@ -87,6 +87,14 @@ Depending on the request type, payload can be:
    User address: a 64-bit user address
    mmap offset: 64-bit offset where region starts in the mapped memory
 
+* Log description
+   ---------------------------
+   | log size | log offset |
+   ---------------------------
+   log size: size of area used for logging
+   log offset: offset from start of supplied file descriptor
+       where logging starts (i.e. where guest address 0 would be logged)
+
 In QEMU the vhost-user message is implemented with the following struct:
 
 typedef struct VhostUserMsg {
@@ -138,6 +146,29 @@ As older slaves don't support negotiating protocol features,
 a feature bit was dedicated for this purpose:
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
 
+Starting and stopping rings
+----------------------
+Client must only process each ring when it is both started and enabled.
+
+If VHOST_USER_F_PROTOCOL_FEATURES has not been negotiated, the ring is initialized
+in an enabled state.
+
+If VHOST_USER_F_PROTOCOL_FEATURES has been negotiated, the ring is initialized
+in a disabled state. Client must not process it until ring is enabled by
+VHOST_USER_SET_VRING_ENABLE with parameter 1, or after it has been disabled by
+VHOST_USER_SET_VRING_ENABLE with parameter 0.
+
+Each ring is initialized in a stopped state, client must not process it until
+ring is started, or after it has been stopped.
+
+Client must start ring upon receiving a kick (that is, detecting that file
+descriptor is readable) on the descriptor specified by
+VHOST_USER_SET_VRING_KICK, and stop ring upon receiving
+VHOST_USER_GET_VRING_BASE.
+
+While processing the rings (when they are started and enabled), client must
+support changing some configuration aspects on the fly.
+
 Multiple queue support
 ----------------------
 
@@ -162,9 +193,13 @@ the slave makes to the memory mapped regions. The client should mark
 the dirty pages in a log. Once it complies to this logging, it may
 declare the VHOST_F_LOG_ALL vhost feature.
 
+To start/stop logging of data/used ring writes, server may send messages
+VHOST_USER_SET_FEATURES with VHOST_F_LOG_ALL and VHOST_USER_SET_VRING_ADDR with
+VHOST_VRING_F_LOG in ring's flags set to 1/0, respectively.
+
 All the modifications to memory pointed by vring "descriptor" should
 be marked. Modifications to "used" vring should be marked if
-VHOST_VRING_F_LOG is part of ring's features.
+VHOST_VRING_F_LOG is part of ring's flags.
 
 Dirty pages are of size:
 #define VHOST_LOG_PAGE 0x1000
@@ -173,22 +208,35 @@ The log memory fd is provided in the ancillary data of
 VHOST_USER_SET_LOG_BASE message when the slave has
 VHOST_USER_PROTOCOL_F_LOG_SHMFD protocol feature.
 
-The size of the log may be computed by using all the known guest
+The size of the log is supplied as part of VhostUserMsg
-addresses. The log covers from address 0 to the maximum of guest
+which should be large enough to cover all known guest
+addresses. Log starts at the supplied offset in the
+supplied file descriptor.
+The log covers from address 0 to the maximum of guest
 regions. In pseudo-code, to mark page at "addr" as dirty:
 
 page = addr / VHOST_LOG_PAGE
 log[page / 8] |= 1 << page % 8
 
+Where addr is the guest physical address.
+
 Use atomic operations, as the log may be concurrently manipulated.
 
+Note that when logging modifications to the used ring (when VHOST_VRING_F_LOG
+is set for this ring), log_guest_addr should be used to calculate the log
+offset: the write to first byte of the used ring is logged at this offset from
+log start. Also note that this value might be outside the legal guest physical
+address range (i.e. does not have to be covered by the VhostUserMemory table),
+but the bit offset of the last byte of the ring must fall within
+the size supplied by VhostUserLog.
+
 VHOST_USER_SET_LOG_FD is an optional message with an eventfd in
 ancillary data, it may be used to inform the master that the log has
 been modified.
 
-Once the source has finished migration, VHOST_USER_RESET_OWNER message
+Once the source has finished migration, rings will be stopped by
-will be sent by the source. No further update must be done before the
+the source. No further update must be done before rings are
-destination takes over with new regions & rings.
+restarted.
 
 Protocol features
 -----------------
@@ -259,11 +307,13 @@ Message types
  * VHOST_USER_RESET_OWNER
 
       Id: 4
-      Equivalent ioctl: VHOST_RESET_OWNER
       Master payload: N/A
 
-      Issued when a new connection is about to be closed. The Master will no
+      This is no longer used. Used to be sent to request stopping
-      longer own this connection (and will usually close it).
+      all rings, but some clients interpreted it to also discard
+      connection state (this interpretation would lead to bugs).
+      It is recommended that clients either ignore this message,
+      or use it to stop all rings.
 
  * VHOST_USER_SET_MEM_TABLE
 
@@ -388,6 +438,8 @@ Message types
       Master payload: vring state description
 
       Signal slave to enable or disable corresponding vring.
+      This request should be sent only when VHOST_USER_F_PROTOCOL_FEATURES
+      has been negotiated.
 
  * VHOST_USER_SEND_RARP
 

exec.c

@@ -51,6 +51,7 @@
 #include "qemu/main-loop.h"
 #include "translate-all.h"
 #include "sysemu/replay.h"
+#include "sysemu/qtest.h"
 
 #include "exec/memory-internal.h"
 #include "exec/ram_addr.h"
@@ -1196,8 +1197,10 @@ static long gethugepagesize(const char *path, Error **errp)
         return 0;
     }
 
-    if (fs.f_type != HUGETLBFS_MAGIC)
+    if (!qtest_driver() &&
+        fs.f_type != HUGETLBFS_MAGIC) {
         fprintf(stderr, "Warning: path not on HugeTLBFS: %s\n", path);
+    }
 
     return fs.f_bsize;
 }

hw/acpi/core.c

@@ -625,8 +625,12 @@ void acpi_pm1_cnt_reset(ACPIREGS *ar)
 void acpi_gpe_init(ACPIREGS *ar, uint8_t len)
 {
     ar->gpe.len = len;
-    ar->gpe.sts = g_malloc0(len / 2);
+    /* Only first len / 2 bytes are ever used,
-    ar->gpe.en = g_malloc0(len / 2);
+     * but the caller in ich9.c migrates full len bytes.
+     * TODO: fix ich9.c and drop the extra allocation.
+     */
+    ar->gpe.sts = g_malloc0(len);
+    ar->gpe.en = g_malloc0(len);
 }
 
 void acpi_gpe_reset(ACPIREGS *ar)

hw/core/machine.c

@@ -462,11 +462,6 @@ bool machine_usb(MachineState *machine)
     return machine->usb;
 }
 
-bool machine_iommu(MachineState *machine)
-{
-    return machine->iommu;
-}
-
 bool machine_kernel_irqchip_allowed(MachineState *machine)
 {
     return machine->kernel_irqchip_allowed;

hw/net/vhost_net.c

@@ -77,14 +77,8 @@ static const int user_feature_bits[] = {
     VIRTIO_NET_F_HOST_ECN,
     VIRTIO_NET_F_HOST_UFO,
     VIRTIO_NET_F_MRG_RXBUF,
-    VIRTIO_NET_F_STATUS,
-    VIRTIO_NET_F_CTRL_VQ,
-    VIRTIO_NET_F_CTRL_RX,
-    VIRTIO_NET_F_CTRL_VLAN,
-    VIRTIO_NET_F_CTRL_RX_EXTRA,
-    VIRTIO_NET_F_CTRL_MAC_ADDR,
-    VIRTIO_NET_F_CTRL_GUEST_OFFLOADS,
 
+    /* This bit implies RARP isn't sent by QEMU out of band */
     VIRTIO_NET_F_GUEST_ANNOUNCE,
 
     VIRTIO_NET_F_MQ,
@@ -292,12 +286,6 @@ static void vhost_net_stop_one(struct vhost_net *net,
             int r = vhost_ops->vhost_net_set_backend(&net->dev, &file);
             assert(r >= 0);
         }
-    } else if (net->nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER) {
-        for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {
-            const VhostOps *vhost_ops = net->dev.vhost_ops;
-            int r = vhost_ops->vhost_reset_device(&net->dev);
-            assert(r >= 0);
-        }
     }
     if (net->nc->info->poll) {
         net->nc->info->poll(net->nc, true);

hw/pci-host/piix.c

@@ -34,6 +34,7 @@
 #include "sysemu/sysemu.h"
 #include "hw/i386/ioapic.h"
 #include "qapi/visitor.h"
+#include "qemu/error-report.h"
 
 /*
  * I440FX chipset data sheet.
@@ -301,6 +302,10 @@ static void i440fx_pcihost_realize(DeviceState *dev, Error **errp)
 static void i440fx_realize(PCIDevice *dev, Error **errp)
 {
     dev->config[I440FX_SMRAM] = 0x02;
+
+    if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
+        error_report("warning: i440fx doesn't support emulated iommu");
+    }
 }
 
 PCIBus *i440fx_init(const char *host_type, const char *pci_type,

hw/pci-host/q35.c

@@ -506,7 +506,7 @@ static void mch_realize(PCIDevice *d, Error **errp)
                  PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE, PAM_EXPAN_SIZE);
     }
     /* Intel IOMMU (VT-d) */
-    if (machine_iommu(current_machine)) {
+    if (object_property_get_bool(qdev_get_machine(), "iommu", NULL)) {
         mch_init_dmar(mch);
     }
 }

hw/virtio/vhost-user.c

@@ -121,8 +121,8 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
 
     r = qemu_chr_fe_read_all(chr, p, size);
     if (r != size) {
-        error_report("Failed to read msg header. Read %d instead of %d.", r,
+        error_report("Failed to read msg header. Read %d instead of %d."
-                size);
+                     " Original request %d.", r, size, msg->request);
         goto fail;
     }
 
@@ -206,7 +206,7 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
     VhostUserMsg msg = {
         .request = VHOST_USER_SET_LOG_BASE,
         .flags = VHOST_USER_VERSION,
-        .payload.log.mmap_size = log->size,
+        .payload.log.mmap_size = log->size * sizeof(*(log->log)),
         .payload.log.mmap_offset = 0,
         .size = sizeof(msg.payload.log),
     };
@@ -333,18 +333,23 @@ static int vhost_user_set_vring_base(struct vhost_dev *dev,
 
 static int vhost_user_set_vring_enable(struct vhost_dev *dev, int enable)
 {
-    struct vhost_vring_state state = {
+    int i;
-        .index = dev->vq_index,
-        .num   = enable,
-    };
 
-    if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ))) {
+    if (!virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) {
         return -1;
     }
 
-    return vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state);
+    for (i = 0; i < dev->nvqs; ++i) {
-}
+        struct vhost_vring_state state = {
+            .index = dev->vq_index + i,
+            .num   = enable,
+        };
 
+        vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state);
+    }
+
+    return 0;
+}
 
 static int vhost_user_get_vring_base(struct vhost_dev *dev,
                                      struct vhost_vring_state *ring)

include/hw/boards.h

@@ -33,7 +33,6 @@ MachineClass *find_default_machine(void);
 extern MachineState *current_machine;
 
 bool machine_usb(MachineState *machine);
-bool machine_iommu(MachineState *machine);
 bool machine_kernel_irqchip_allowed(MachineState *machine);
 bool machine_kernel_irqchip_required(MachineState *machine);
 int machine_kvm_shadow_mem(MachineState *machine);

tests/Makefile

@@ -197,8 +197,9 @@ gcov-files-i386-y += hw/usb/hcd-xhci.c
 check-qtest-i386-y += tests/pc-cpu-test$(EXESUF)
 check-qtest-i386-y += tests/q35-test$(EXESUF)
 gcov-files-i386-y += hw/pci-host/q35.c
-ifeq ($(CONFIG_VHOST_NET),y)
+check-qtest-i386-$(CONFIG_VHOST_NET_TEST_i386) += tests/vhost-user-test$(EXESUF)
-check-qtest-i386-$(CONFIG_LINUX) += tests/vhost-user-test$(EXESUF)
+ifeq ($(CONFIG_VHOST_NET_TEST_i386),)
+check-qtest-x86_64-$(CONFIG_VHOST_NET_TEST_x86_64) += tests/vhost-user-test$(EXESUF)
 endif
 check-qtest-i386-y += tests/test-netfilter$(EXESUF)
 check-qtest-x86_64-y = $(check-qtest-i386-y)

tests/vhost-user-bridge.c

@@ -13,16 +13,22 @@
 /*
  * TODO:
  *     - main should get parameters from the command line.
- *     - implement all request handlers.
+ *     - implement all request handlers. Still not implemented:
+ *          vubr_get_queue_num_exec()
+ *          vubr_send_rarp_exec()
  *     - test for broken requests and virtqueue.
  *     - implement features defined by Virtio 1.0 spec.
  *     - support mergeable buffers and indirect descriptors.
- *     - implement RESET_DEVICE request.
  *     - implement clean shutdown.
  *     - implement non-blocking writes to UDP backend.
  *     - implement polling strategy.
+ *     - implement clean starting/stopping of vq processing
+ *     - implement clean starting/stopping of used and buffers
+ *       dirty page logging.
  */
 
+#define _FILE_OFFSET_BITS 64
+
 #include <stddef.h>
 #include <assert.h>
 #include <stdio.h>
@@ -166,6 +172,8 @@ typedef struct VubrVirtq {
     struct vring_desc *desc;
     struct vring_avail *avail;
     struct vring_used *used;
+    uint64_t log_guest_addr;
+    int enable;
 } VubrVirtq;
 
 /* Based on qemu/hw/virtio/vhost-user.c */
@@ -173,6 +181,8 @@ typedef struct VubrVirtq {
 #define VHOST_MEMORY_MAX_NREGIONS    8
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
 
+#define VHOST_LOG_PAGE 4096
+
 enum VhostUserProtocolFeature {
     VHOST_USER_PROTOCOL_F_MQ = 0,
     VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
@@ -220,6 +230,11 @@ typedef struct VhostUserMemory {
     VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
 } VhostUserMemory;
 
+typedef struct VhostUserLog {
+    uint64_t mmap_size;
+    uint64_t mmap_offset;
+} VhostUserLog;
+
 typedef struct VhostUserMsg {
     VhostUserRequest request;
 
@@ -234,6 +249,7 @@ typedef struct VhostUserMsg {
         struct vhost_vring_state state;
         struct vhost_vring_addr addr;
         VhostUserMemory memory;
+        VhostUserLog log;
     } payload;
     int fds[VHOST_MEMORY_MAX_NREGIONS];
     int fd_num;
@@ -265,8 +281,13 @@ typedef struct VubrDev {
     uint32_t nregions;
     VubrDevRegion regions[VHOST_MEMORY_MAX_NREGIONS];
     VubrVirtq vq[MAX_NR_VIRTQUEUE];
+    int log_call_fd;
+    uint64_t log_size;
+    uint8_t *log_table;
     int backend_udp_sock;
     struct sockaddr_in backend_udp_dest;
+    int ready;
+    uint64_t features;
 } VubrDev;
 
 static const char *vubr_request_str[] = {
@@ -368,7 +389,12 @@ vubr_message_read(int conn_fd, VhostUserMsg *vmsg)
 
     rc = recvmsg(conn_fd, &msg, 0);
 
-    if (rc <= 0) {
+    if (rc == 0) {
+        vubr_die("recvmsg");
+        fprintf(stderr, "Peer disconnected.\n");
+        exit(1);
+    }
+    if (rc < 0) {
         vubr_die("recvmsg");
     }
 
@@ -395,7 +421,12 @@ vubr_message_read(int conn_fd, VhostUserMsg *vmsg)
 
     if (vmsg->size) {
         rc = read(conn_fd, &vmsg->payload, vmsg->size);
-        if (rc <= 0) {
+        if (rc == 0) {
+            vubr_die("recvmsg");
+            fprintf(stderr, "Peer disconnected.\n");
+            exit(1);
+        }
+        if (rc < 0) {
             vubr_die("recvmsg");
         }
 
@@ -455,6 +486,16 @@ vubr_consume_raw_packet(VubrDev *dev, uint8_t *buf, uint32_t len)
     vubr_backend_udp_sendbuf(dev, buf + hdrlen, len - hdrlen);
 }
 
+/* Kick the log_call_fd if required. */
+static void
+vubr_log_kick(VubrDev *dev)
+{
+    if (dev->log_call_fd != -1) {
+        DPRINT("Kicking the QEMU's log...\n");
+        eventfd_write(dev->log_call_fd, 1);
+    }
+}
+
 /* Kick the guest if necessary. */
 static void
 vubr_virtqueue_kick(VubrVirtq *vq)
@@ -465,12 +506,40 @@ vubr_virtqueue_kick(VubrVirtq *vq)
     }
 }
 
+static void
+vubr_log_page(uint8_t *log_table, uint64_t page)
+{
+    DPRINT("Logged dirty guest page: %"PRId64"\n", page);
+    atomic_or(&log_table[page / 8], 1 << (page % 8));
+}
+
+static void
+vubr_log_write(VubrDev *dev, uint64_t address, uint64_t length)
+{
+    uint64_t page;
+
+    if (!(dev->features & (1ULL << VHOST_F_LOG_ALL)) ||
+        !dev->log_table || !length) {
+        return;
+    }
+
+    assert(dev->log_size > ((address + length - 1) / VHOST_LOG_PAGE / 8));
+
+    page = address / VHOST_LOG_PAGE;
+    while (page * VHOST_LOG_PAGE < address + length) {
+        vubr_log_page(dev->log_table, page);
+        page += VHOST_LOG_PAGE;
+    }
+    vubr_log_kick(dev);
+}
+
 static void
 vubr_post_buffer(VubrDev *dev, VubrVirtq *vq, uint8_t *buf, int32_t len)
 {
-    struct vring_desc *desc   = vq->desc;
+    struct vring_desc *desc = vq->desc;
     struct vring_avail *avail = vq->avail;
-    struct vring_used *used   = vq->used;
+    struct vring_used *used = vq->used;
+    uint64_t log_guest_addr = vq->log_guest_addr;
 
     unsigned int size = vq->size;
 
@@ -510,6 +579,7 @@ vubr_post_buffer(VubrDev *dev, VubrVirtq *vq, uint8_t *buf, int32_t len)
 
     if (len <= chunk_len) {
         memcpy(chunk_start, buf, len);
+        vubr_log_write(dev, desc[i].addr, len);
     } else {
         fprintf(stderr,
                 "Received too long packet from the backend. Dropping...\n");
@@ -519,11 +589,17 @@ vubr_post_buffer(VubrDev *dev, VubrVirtq *vq, uint8_t *buf, int32_t len)
     /* Add descriptor to the used ring. */
     used->ring[u_index].id = d_index;
     used->ring[u_index].len = len;
+    vubr_log_write(dev,
+                   log_guest_addr + offsetof(struct vring_used, ring[u_index]),
+                   sizeof(used->ring[u_index]));
 
     vq->last_avail_index++;
     vq->last_used_index++;
 
     atomic_mb_set(&used->idx, vq->last_used_index);
+    vubr_log_write(dev,
+                   log_guest_addr + offsetof(struct vring_used, idx),
+                   sizeof(used->idx));
 
     /* Kick the guest if necessary. */
     vubr_virtqueue_kick(vq);
@@ -532,9 +608,10 @@ vubr_post_buffer(VubrDev *dev, VubrVirtq *vq, uint8_t *buf, int32_t len)
 static int
 vubr_process_desc(VubrDev *dev, VubrVirtq *vq)
 {
-    struct vring_desc *desc   = vq->desc;
+    struct vring_desc *desc = vq->desc;
     struct vring_avail *avail = vq->avail;
-    struct vring_used *used   = vq->used;
+    struct vring_used *used = vq->used;
+    uint64_t log_guest_addr = vq->log_guest_addr;
 
     unsigned int size = vq->size;
 
@@ -552,6 +629,8 @@ vubr_process_desc(VubrDev *dev, VubrVirtq *vq)
         void *chunk_start = (void *)gpa_to_va(dev, desc[i].addr);
         uint32_t chunk_len = desc[i].len;
 
+        assert(!(desc[i].flags & VRING_DESC_F_WRITE));
+
         if (len + chunk_len < buf_size) {
             memcpy(buf + len, chunk_start, chunk_len);
             DPRINT("%d ", chunk_len);
@@ -577,6 +656,9 @@ vubr_process_desc(VubrDev *dev, VubrVirtq *vq)
     /* Add descriptor to the used ring. */
     used->ring[u_index].id = d_index;
     used->ring[u_index].len = len;
+    vubr_log_write(dev,
+                   log_guest_addr + offsetof(struct vring_used, ring[u_index]),
+                   sizeof(used->ring[u_index]));
 
     vubr_consume_raw_packet(dev, buf, len);
 
@@ -588,6 +670,7 @@ vubr_process_avail(VubrDev *dev, VubrVirtq *vq)
 {
     struct vring_avail *avail = vq->avail;
     struct vring_used *used = vq->used;
+    uint64_t log_guest_addr = vq->log_guest_addr;
 
     while (vq->last_avail_index != atomic_mb_read(&avail->idx)) {
         vubr_process_desc(dev, vq);
@@ -596,6 +679,9 @@ vubr_process_avail(VubrDev *dev, VubrVirtq *vq)
     }
 
     atomic_mb_set(&used->idx, vq->last_used_index);
+    vubr_log_write(dev,
+                   log_guest_addr + offsetof(struct vring_used, idx),
+                   sizeof(used->idx));
 }
 
 static void
@@ -609,6 +695,10 @@ vubr_backend_recv_cb(int sock, void *ctx)
     int buflen = sizeof(buf);
     int len;
 
+    if (!dev->ready) {
+        return;
+    }
+
     DPRINT("\n\n   ***   IN UDP RECEIVE CALLBACK    ***\n\n");
 
     uint16_t avail_index = atomic_mb_read(&rx_vq->avail->idx);
@@ -656,14 +746,14 @@ vubr_get_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
     vmsg->payload.u64 =
             ((1ULL << VIRTIO_NET_F_MRG_RXBUF) |
-             (1ULL << VIRTIO_NET_F_CTRL_VQ) |
+             (1ULL << VHOST_F_LOG_ALL) |
-             (1ULL << VIRTIO_NET_F_CTRL_RX) |
+             (1ULL << VHOST_USER_F_PROTOCOL_FEATURES));
-             (1ULL << VHOST_F_LOG_ALL));
+
     vmsg->size = sizeof(vmsg->payload.u64);
 
     DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
 
-    /* reply */
+    /* Reply */
     return 1;
 }
 
@@ -671,6 +761,7 @@ static int
 vubr_set_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
     DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
+    dev->features = vmsg->payload.u64;
     return 0;
 }
 
@@ -680,10 +771,28 @@ vubr_set_owner_exec(VubrDev *dev, VhostUserMsg *vmsg)
     return 0;
 }
 
+static void
+vubr_close_log(VubrDev *dev)
+{
+    if (dev->log_table) {
+        if (munmap(dev->log_table, dev->log_size) != 0) {
+            vubr_die("munmap()");
+        }
+
+        dev->log_table = 0;
+    }
+    if (dev->log_call_fd != -1) {
+        close(dev->log_call_fd);
+        dev->log_call_fd = -1;
+    }
+}
+
 static int
 vubr_reset_device_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    DPRINT("Function %s() not implemented yet.\n", __func__);
+    vubr_close_log(dev);
+    dev->ready = 0;
+    dev->features = 0;
     return 0;
 }
 
@@ -710,9 +819,9 @@ vubr_set_mem_table_exec(VubrDev *dev, VhostUserMsg *vmsg)
         DPRINT("    mmap_offset      0x%016"PRIx64"\n",
                msg_region->mmap_offset);
 
-        dev_region->gpa         = msg_region->guest_phys_addr;
+        dev_region->gpa = msg_region->guest_phys_addr;
-        dev_region->size        = msg_region->memory_size;
+        dev_region->size = msg_region->memory_size;
-        dev_region->qva         = msg_region->userspace_addr;
+        dev_region->qva = msg_region->userspace_addr;
         dev_region->mmap_offset = msg_region->mmap_offset;
 
         /* We don't use offset argument of mmap() since the
@@ -736,14 +845,38 @@ vubr_set_mem_table_exec(VubrDev *dev, VhostUserMsg *vmsg)
 static int
 vubr_set_log_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    DPRINT("Function %s() not implemented yet.\n", __func__);
+    int fd;
-    return 0;
+    uint64_t log_mmap_size, log_mmap_offset;
+    void *rc;
+
+    assert(vmsg->fd_num == 1);
+    fd = vmsg->fds[0];
+
+    assert(vmsg->size == sizeof(vmsg->payload.log));
+    log_mmap_offset = vmsg->payload.log.mmap_offset;
+    log_mmap_size = vmsg->payload.log.mmap_size;
+    DPRINT("Log mmap_offset: %"PRId64"\n", log_mmap_offset);
+    DPRINT("Log mmap_size:   %"PRId64"\n", log_mmap_size);
+
+    rc = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
+              log_mmap_offset);
+    if (rc == MAP_FAILED) {
+        vubr_die("mmap");
+    }
+    dev->log_table = rc;
+    dev->log_size = log_mmap_size;
+
+    vmsg->size = sizeof(vmsg->payload.u64);
+    /* Reply */
+    return 1;
 }
 
 static int
 vubr_set_log_fd_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    DPRINT("Function %s() not implemented yet.\n", __func__);
+    assert(vmsg->fd_num == 1);
+    dev->log_call_fd = vmsg->fds[0];
+    DPRINT("Got log_call_fd: %d\n", vmsg->fds[0]);
     return 0;
 }
 
@@ -777,6 +910,7 @@ vubr_set_vring_addr_exec(VubrDev *dev, VhostUserMsg *vmsg)
     vq->desc = (struct vring_desc *)qva_to_va(dev, vra->desc_user_addr);
     vq->used = (struct vring_used *)qva_to_va(dev, vra->used_user_addr);
     vq->avail = (struct vring_avail *)qva_to_va(dev, vra->avail_user_addr);
+    vq->log_guest_addr = vra->log_guest_addr;
 
     DPRINT("Setting virtq addresses:\n");
     DPRINT("    vring_desc  at %p\n", vq->desc);
@@ -803,8 +937,18 @@ vubr_set_vring_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 static int
 vubr_get_vring_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    DPRINT("Function %s() not implemented yet.\n", __func__);
+    unsigned int index = vmsg->payload.state.index;
-    return 0;
+
+    DPRINT("State.index: %d\n", index);
+    vmsg->payload.state.num = dev->vq[index].last_avail_index;
+    vmsg->size = sizeof(vmsg->payload.state);
+    /* FIXME: this is a work-around for a bug in QEMU enabling
+     * too early vrings. When protocol features are enabled,
+     * we have to respect * VHOST_USER_SET_VRING_ENABLE request. */
+    dev->ready = 0;
+
+    /* Reply */
+    return 1;
 }
 
 static int
@@ -829,7 +973,17 @@ vubr_set_vring_kick_exec(VubrDev *dev, VhostUserMsg *vmsg)
         DPRINT("Waiting for kicks on fd: %d for vq: %d\n",
                dev->vq[index].kick_fd, index);
     }
+    /* We temporarily use this hack to determine that both TX and RX
+     * queues are set up and ready for processing.
+     * FIXME: we need to rely in VHOST_USER_SET_VRING_ENABLE and
+     * actual kicks. */
+    if (dev->vq[0].kick_fd != -1 &&
+        dev->vq[1].kick_fd != -1) {
+        dev->ready = 1;
+        DPRINT("vhost-user-bridge is ready for processing queues.\n");
+    }
     return 0;
+
 }
 
 static int
@@ -858,9 +1012,12 @@ vubr_set_vring_err_exec(VubrDev *dev, VhostUserMsg *vmsg)
 static int
 vubr_get_protocol_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    /* FIXME: unimplented */
+    vmsg->payload.u64 = 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD;
     DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
-    return 0;
+    vmsg->size = sizeof(vmsg->payload.u64);
+
+    /* Reply */
+    return 1;
 }
 
 static int
@@ -881,7 +1038,12 @@ vubr_get_queue_num_exec(VubrDev *dev, VhostUserMsg *vmsg)
 static int
 vubr_set_vring_enable_exec(VubrDev *dev, VhostUserMsg *vmsg)
 {
-    DPRINT("Function %s() not implemented yet.\n", __func__);
+    unsigned int index = vmsg->payload.state.index;
+    unsigned int enable = vmsg->payload.state.num;
+
+    DPRINT("State.index: %d\n", index);
+    DPRINT("State.enable:   %d\n", enable);
+    dev->vq[index].enable = enable;
     return 0;
 }
 
@@ -987,7 +1149,7 @@ vubr_accept_cb(int sock, void *ctx)
     socklen_t len = sizeof(un);
 
     conn_fd = accept(sock, (struct sockaddr *) &un, &len);
-    if (conn_fd  == -1) {
+    if (conn_fd == -1) {
         vubr_die("accept()");
     }
     DPRINT("Got connection from remote peer on sock %d\n", conn_fd);
@@ -1009,9 +1171,17 @@ vubr_new(const char *path)
             .size = 0,
             .last_avail_index = 0, .last_used_index = 0,
             .desc = 0, .avail = 0, .used = 0,
+            .enable = 0,
         };
     }
 
+    /* Init log */
+    dev->log_call_fd = -1;
+    dev->log_size = 0;
+    dev->log_table = 0;
+    dev->ready = 0;
+    dev->features = 0;
+
     /* Get a UNIX socket. */
     dev->sock = socket(AF_UNIX, SOCK_STREAM, 0);
     if (dev->sock == -1) {

tests/vhost-user-test.c

@@ -70,6 +70,7 @@ typedef enum VhostUserRequest {
     VHOST_USER_SET_VRING_ERR = 14,
     VHOST_USER_GET_PROTOCOL_FEATURES = 15,
     VHOST_USER_SET_PROTOCOL_FEATURES = 16,
+    VHOST_USER_SET_VRING_ENABLE = 18,
     VHOST_USER_MAX
 } VhostUserRequest;
 
@@ -315,8 +316,10 @@ static void chr_read(void *opaque, const uint8_t *buf, int size)
         g_cond_signal(&s->data_cond);
         break;
 
-    case VHOST_USER_RESET_OWNER:
+    case VHOST_USER_SET_VRING_ENABLE:
-        s->fds_num = 0;
+        if (!msg.payload.state.num) {
+            s->fds_num = 0;
+        }
         break;
 
     default:

vl.c

@@ -4288,14 +4288,23 @@ int main(int argc, char **argv, char **envp)
     page_size_init();
     socket_init();
 
-    if (qemu_opts_foreach(qemu_find_opts("object"),
+    if (qemu_opts_foreach(qemu_find_opts("chardev"),
-                          object_create,
+                          chardev_init_func, NULL, NULL)) {
-                          object_create_initial, NULL)) {
         exit(1);
     }
 
-    if (qemu_opts_foreach(qemu_find_opts("chardev"),
+    if (qtest_chrdev) {
-                          chardev_init_func, NULL, NULL)) {
+        Error *local_err = NULL;
+        qtest_init(qtest_chrdev, qtest_log, &local_err);
+        if (local_err) {
+            error_report_err(local_err);
+            exit(1);
+        }
+    }
+
+    if (qemu_opts_foreach(qemu_find_opts("object"),
+                          object_create,
+                          object_create_initial, NULL)) {
         exit(1);
     }
 
@@ -4325,15 +4334,6 @@ int main(int argc, char **argv, char **envp)
 
     configure_accelerator(current_machine);
 
-    if (qtest_chrdev) {
-        Error *local_err = NULL;
-        qtest_init(qtest_chrdev, qtest_log, &local_err);
-        if (local_err) {
-            error_report_err(local_err);
-            exit(1);
-        }
-    }
-
     machine_opts = qemu_get_machine_opts();
     kernel_filename = qemu_opt_get(machine_opts, "kernel");
     initrd_filename = qemu_opt_get(machine_opts, "initrd");