On 12/17/2015 11:11 AM, Yuanhan Liu wrote:
> 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 at linux.intel.com>
> Signed-off-by: Victor Kaplansky <victork at redhat.com
> ---
>
> v2: workaround mmap issue when offset is not zero
> ---
> lib/librte_vhost/rte_virtio_net.h | 4 ++-
> lib/librte_vhost/vhost_user/vhost-net-user.c | 7 ++--
> lib/librte_vhost/vhost_user/vhost-net-user.h | 6 ++++
> lib/librte_vhost/vhost_user/virtio-net-user.c | 48
> +++++++++++++++++++++++++++
> lib/librte_vhost/vhost_user/virtio-net-user.h | 1 +
> 5 files changed, 63 insertions(+), 3 deletions(-)
>
> diff --git a/lib/librte_vhost/rte_virtio_net.h
> b/lib/librte_vhost/rte_virtio_net.h
> index 10dcb90..8acee02 100644
> --- 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
> --- 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
> --- 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..b77c9b3 100644
> --- 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 be
> + * failed when offset is not page size aligned.
> + */
s /will be failed/will fail/
mmap will fail when offset is not zero.
Also we only know this workaround is for hugetlbfs. Not sure of other
tmpfs, so mention hugetlbfs here.
> + addr = mmap(0, size + off, 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;
(uint64_t)(uintptr_t)RTE_PTR_ADD(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
> --- 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 *);
>
