Cleanup part is missing in this patch.
We should close and clear postcopy_ufd in vhost_backend_cleanup().
Best regards, Ilya Maximets.
On 04.10.2018 11:13, Maxime Coquelin wrote:
> This patch opens a userfaultfd and sends it back to Qemu's
> VHOST_USER_POSTCOPY_ADVISE request.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> lib/librte_vhost/vhost.h | 2 ++
> lib/librte_vhost/vhost_user.c | 44 +++++++++++++++++++++++++++++++++++
> lib/librte_vhost/vhost_user.h | 3 ++-
> 3 files changed, 48 insertions(+), 1 deletion(-)
>
> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
> index 25ffd7614..21722d8a8 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -363,6 +363,8 @@ struct virtio_net {
> int slave_req_fd;
> rte_spinlock_t slave_req_lock;
>
> + int postcopy_ufd;
> +
> /*
> * Device id to identify a specific backend device.
> * It's set to -1 for the default software implementation.
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> index 0a1934649..3d4fc60fc 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -24,13 +24,19 @@
> #include <stdlib.h>
> #include <string.h>
> #include <unistd.h>
> +#include <fcntl.h>
> +#include <sys/ioctl.h>
> #include <sys/mman.h>
> #include <sys/types.h>
> #include <sys/stat.h>
> +#include <sys/syscall.h>
> #include <assert.h>
> #ifdef RTE_LIBRTE_VHOST_NUMA
> #include <numaif.h>
> #endif
> +#ifdef RTE_LIBRTE_VHOST_POSTCOPY
> +#include <linux/userfaultfd.h>
> +#endif
>
> #include <rte_common.h>
> #include <rte_malloc.h>
> @@ -69,6 +75,7 @@ static const char *vhost_message_str[VHOST_USER_MAX] = {
> [VHOST_USER_IOTLB_MSG] = "VHOST_USER_IOTLB_MSG",
> [VHOST_USER_CRYPTO_CREATE_SESS] = "VHOST_USER_CRYPTO_CREATE_SESS",
> [VHOST_USER_CRYPTO_CLOSE_SESS] = "VHOST_USER_CRYPTO_CLOSE_SESS",
> + [VHOST_USER_POSTCOPY_ADVISE] = "VHOST_USER_POSTCOPY_ADVISE",
> };
>
> /* The possible results of a message handling function */
> @@ -1509,6 +1516,42 @@ vhost_user_iotlb_msg(struct virtio_net **pdev, struct
> VhostUserMsg *msg,
> return VH_RESULT_OK;
> }
>
> +static int
> +vhost_user_set_postcopy_advise(struct virtio_net **pdev,
> + struct VhostUserMsg *msg,
> + int main_fd __rte_unused)
> +{
> + struct virtio_net *dev = *pdev;
> +#ifdef RTE_LIBRTE_VHOST_POSTCOPY
> + struct uffdio_api api_struct;
> +
> + dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
> +
> + if (dev->postcopy_ufd == -1) {
> + RTE_LOG(ERR, VHOST_CONFIG, "Userfaultfd not available: %s\n",
> + strerror(errno));
> + return VH_RESULT_ERR;
> + }
> + api_struct.api = UFFD_API;
> + api_struct.features = 0;
> + if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) {
> + RTE_LOG(ERR, VHOST_CONFIG, "UFFDIO_API ioctl failure: %s\n",
> + strerror(errno));
> + close(dev->postcopy_ufd);
> + return VH_RESULT_ERR;
> + }
> + msg->fds[0] = dev->postcopy_ufd;
> + msg->fd_num = 1;
> +
> + return VH_RESULT_REPLY;
> +#else
> + dev->postcopy_ufd = -1;
> + msg->fd_num = 0;
> +
> + return VH_RESULT_ERR;
> +#endif
> +}
> +
> typedef int (*vhost_message_handler_t)(struct virtio_net **pdev,
> struct VhostUserMsg *msg,
> int main_fd);
> @@ -1536,6 +1579,7 @@ static vhost_message_handler_t
> vhost_message_handlers[VHOST_USER_MAX] = {
> [VHOST_USER_NET_SET_MTU] = vhost_user_net_set_mtu,
> [VHOST_USER_SET_SLAVE_REQ_FD] = vhost_user_set_req_fd,
> [VHOST_USER_IOTLB_MSG] = vhost_user_iotlb_msg,
> + [VHOST_USER_POSTCOPY_ADVISE] = vhost_user_set_postcopy_advise,
> };
>
>
> diff --git a/lib/librte_vhost/vhost_user.h b/lib/librte_vhost/vhost_user.h
> index dd0262f8f..2030b40a5 100644
> --- a/lib/librte_vhost/vhost_user.h
> +++ b/lib/librte_vhost/vhost_user.h
> @@ -50,7 +50,8 @@ typedef enum VhostUserRequest {
> VHOST_USER_IOTLB_MSG = 22,
> VHOST_USER_CRYPTO_CREATE_SESS = 26,
> VHOST_USER_CRYPTO_CLOSE_SESS = 27,
> - VHOST_USER_MAX = 28
> + VHOST_USER_POSTCOPY_ADVISE = 28,
> + VHOST_USER_MAX = 29
> } VhostUserRequest;
>
> typedef enum VhostUserSlaveRequest {
>
