vhost: handle dirty pages logging request

VHOST_USER_SET_LOG_BASE request is used to tell the backend (dpdk
vhost-user) where we should log dirty pages, and how big the log
buffer is.

This request introduces a new payload:

    typedef struct VhostUserLog {
            uint64_t mmap_size;
            uint64_t mmap_offset;
    } VhostUserLog;

Also, a fd is delivered from QEMU by ancillary data.

With those info given, an area of memory is mmaped, assigned
to dev->log_base, for logging dirty pages.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Victor Kaplansky <victork@redhat.com>
Tested-by: Pavel Fedin <p.fedin@samsung.com>

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 10dcb90..8acee02 100644 (file)
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -129,7 +129,9 @@ struct virtio_net {
        char                    ifname[IF_NAME_SZ];     /**< Name of the tap device or socket path. */
        uint32_t                virt_qp_nb;     /**< number of queue pair we have allocated */
        void                    *priv;          /**< private context */
-       uint64_t                reserved[64];   /**< Reserve some spaces for future extension. */
+       uint64_t                log_size;       /**< Size of log area */
+       uint64_t                log_base;       /**< Where dirty pages are logged */
+       uint64_t                reserved[62];   /**< Reserve some spaces for future extension. */
        struct vhost_virtqueue  *virtqueue[VHOST_MAX_QUEUE_PAIRS * 2];  /**< Contains all virtqueue information. */
 } __rte_cache_aligned;
 

diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.c b/lib/librte_vhost/vhost_user/vhost-net-user.c
index 8b7a448..32ad6f6 100644 (file)
--- a/lib/librte_vhost/vhost_user/vhost-net-user.c
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.c
@@ -388,9 +388,12 @@ vserver_message_handler(int connfd, void *dat, int *remove)
                break;
 
        case VHOST_USER_SET_LOG_BASE:
-               RTE_LOG(INFO, VHOST_CONFIG, "not implemented.\n");
-               break;
+               user_set_log_base(ctx, &msg);
 
+               /* it needs a reply */
+               msg.size = sizeof(msg.payload.u64);
+               send_vhost_message(connfd, &msg);
+               break;
        case VHOST_USER_SET_LOG_FD:
                close(msg.fds[0]);
                RTE_LOG(INFO, VHOST_CONFIG, "not implemented.\n");

diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.h b/lib/librte_vhost/vhost_user/vhost-net-user.h
index 38637cc..6d252a3 100644 (file)
--- a/lib/librte_vhost/vhost_user/vhost-net-user.h
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.h
@@ -83,6 +83,11 @@ 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;
 
@@ -97,6 +102,7 @@ typedef struct VhostUserMsg {
                struct vhost_vring_state state;
                struct vhost_vring_addr addr;
                VhostUserMemory memory;
+               VhostUserLog    log;
        } payload;
        int fds[VHOST_MEMORY_MAX_NREGIONS];
 } __attribute((packed)) VhostUserMsg;

diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c b/lib/librte_vhost/vhost_user/virtio-net-user.c
index 2934d1c..0f3b163 100644 (file)
--- a/lib/librte_vhost/vhost_user/virtio-net-user.c
+++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
@@ -365,3 +365,51 @@ user_set_protocol_features(struct vhost_device_ctx ctx,
 
        dev->protocol_features = protocol_features;
 }
+
+int
+user_set_log_base(struct vhost_device_ctx ctx,
+                struct VhostUserMsg *msg)
+{
+       struct virtio_net *dev;
+       int fd = msg->fds[0];
+       uint64_t size, off;
+       void *addr;
+
+       dev = get_device(ctx);
+       if (!dev)
+               return -1;
+
+       if (fd < 0) {
+               RTE_LOG(ERR, VHOST_CONFIG, "invalid log fd: %d\n", fd);
+               return -1;
+       }
+
+       if (msg->size != sizeof(VhostUserLog)) {
+               RTE_LOG(ERR, VHOST_CONFIG,
+                       "invalid log base msg size: %"PRId32" != %d\n",
+                       msg->size, (int)sizeof(VhostUserLog));
+               return -1;
+       }
+
+       size = msg->payload.log.mmap_size;
+       off  = msg->payload.log.mmap_offset;
+       RTE_LOG(INFO, VHOST_CONFIG,
+               "log mmap size: %"PRId64", offset: %"PRId64"\n",
+               size, off);
+
+       /*
+        * mmap from 0 to workaround a hugepage mmap bug: mmap will
+        * fail when offset is not page size aligned.
+        */
+       addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+       if (addr == MAP_FAILED) {
+               RTE_LOG(ERR, VHOST_CONFIG, "mmap log base failed!\n");
+               return -1;
+       }
+
+       /* TODO: unmap on stop */
+       dev->log_base = (uint64_t)(uintptr_t)addr + off;
+       dev->log_size = size;
+
+       return 0;
+}

diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.h b/lib/librte_vhost/vhost_user/virtio-net-user.h
index b82108d..013cf38 100644 (file)
--- a/lib/librte_vhost/vhost_user/virtio-net-user.h
+++ b/lib/librte_vhost/vhost_user/virtio-net-user.h
@@ -49,6 +49,7 @@ void user_set_vring_kick(struct vhost_device_ctx, struct VhostUserMsg *);
 
 void user_set_protocol_features(struct vhost_device_ctx ctx,
                                uint64_t protocol_features);
+int user_set_log_base(struct vhost_device_ctx ctx, struct VhostUserMsg *);
 
 int user_get_vring_base(struct vhost_device_ctx, struct vhost_vring_state *);