From: Vincenzo Maffione <v.maffi...@gmail.com> This patch simplifies the netmap backend code by means of the nm_open() helper function provided by netmap_user.h, which hides the details of open(), iotcl() and mmap() carried out on the netmap device.
Moreover, the semantic of nm_open() makes it possible to open special netmap ports (e.g. pipes, monitors) and use special modes (e.g. host rings only, single queue mode, exclusive access). Signed-off-by: Vincenzo Maffione <v.maffi...@gmail.com> Signed-off-by: Jason Wang <jasow...@redhat.com> --- net/netmap.c | 97 ++++++++++++++++++++---------------------------------------- 1 file changed, 32 insertions(+), 65 deletions(-) diff --git a/net/netmap.c b/net/netmap.c index 5558368..27295ab 100644 --- a/net/netmap.c +++ b/net/netmap.c @@ -39,21 +39,12 @@ #include "qemu/error-report.h" #include "qemu/iov.h" -/* Private netmap device info. */ -typedef struct NetmapPriv { - int fd; - size_t memsize; - void *mem; - struct netmap_if *nifp; - struct netmap_ring *rx; - struct netmap_ring *tx; - char fdname[PATH_MAX]; /* Normally "/dev/netmap". */ - char ifname[IFNAMSIZ]; -} NetmapPriv; - typedef struct NetmapState { NetClientState nc; - NetmapPriv me; + struct nm_desc *nmd; + char ifname[IFNAMSIZ]; + struct netmap_ring *tx; + struct netmap_ring *rx; bool read_poll; bool write_poll; struct iovec iov[IOV_MAX]; @@ -90,44 +81,23 @@ pkt_copy(const void *_src, void *_dst, int l) * Open a netmap device. We assume there is only one queue * (which is the case for the VALE bridge). */ -static void netmap_open(NetmapPriv *me, Error **errp) +static struct nm_desc *netmap_open(const NetdevNetmapOptions *nm_opts, + Error **errp) { - int fd; - int err; - size_t l; + struct nm_desc *nmd; struct nmreq req; - me->fd = fd = open(me->fdname, O_RDWR); - if (fd < 0) { - error_setg_file_open(errp, errno, me->fdname); - return; - } memset(&req, 0, sizeof(req)); - pstrcpy(req.nr_name, sizeof(req.nr_name), me->ifname); - req.nr_ringid = NETMAP_NO_TX_POLL; - req.nr_version = NETMAP_API; - err = ioctl(fd, NIOCREGIF, &req); - if (err) { - error_setg_errno(errp, errno, "Unable to register %s", me->ifname); - goto error; - } - l = me->memsize = req.nr_memsize; - me->mem = mmap(0, l, PROT_WRITE | PROT_READ, MAP_SHARED, fd, 0); - if (me->mem == MAP_FAILED) { - error_setg_errno(errp, errno, "Unable to mmap netmap shared memory"); - me->mem = NULL; - goto error; + nmd = nm_open(nm_opts->ifname, &req, NETMAP_NO_TX_POLL, + NULL); + if (nmd == NULL) { + error_setg_errno(errp, errno, "Failed to nm_open() %s", + nm_opts->ifname); + return NULL; } - me->nifp = NETMAP_IF(me->mem, req.nr_offset); - me->tx = NETMAP_TXRING(me->nifp, 0); - me->rx = NETMAP_RXRING(me->nifp, 0); - - return; - -error: - close(me->fd); + return nmd; } static void netmap_send(void *opaque); @@ -136,7 +106,7 @@ static void netmap_writable(void *opaque); /* Set the event-loop handlers for the netmap backend. */ static void netmap_update_fd_handler(NetmapState *s) { - qemu_set_fd_handler(s->me.fd, + qemu_set_fd_handler(s->nmd->fd, s->read_poll ? netmap_send : NULL, s->write_poll ? netmap_writable : NULL, s); @@ -188,7 +158,7 @@ static ssize_t netmap_receive(NetClientState *nc, const uint8_t *buf, size_t size) { NetmapState *s = DO_UPCAST(NetmapState, nc, nc); - struct netmap_ring *ring = s->me.tx; + struct netmap_ring *ring = s->tx; uint32_t i; uint32_t idx; uint8_t *dst; @@ -218,7 +188,7 @@ static ssize_t netmap_receive(NetClientState *nc, ring->slot[i].flags = 0; pkt_copy(buf, dst, size); ring->cur = ring->head = nm_ring_next(ring, i); - ioctl(s->me.fd, NIOCTXSYNC, NULL); + ioctl(s->nmd->fd, NIOCTXSYNC, NULL); return size; } @@ -227,7 +197,7 @@ static ssize_t netmap_receive_iov(NetClientState *nc, const struct iovec *iov, int iovcnt) { NetmapState *s = DO_UPCAST(NetmapState, nc, nc); - struct netmap_ring *ring = s->me.tx; + struct netmap_ring *ring = s->tx; uint32_t last; uint32_t idx; uint8_t *dst; @@ -284,7 +254,7 @@ static ssize_t netmap_receive_iov(NetClientState *nc, /* Now update ring->cur and ring->head. */ ring->cur = ring->head = i; - ioctl(s->me.fd, NIOCTXSYNC, NULL); + ioctl(s->nmd->fd, NIOCTXSYNC, NULL); return iov_size(iov, iovcnt); } @@ -301,7 +271,7 @@ static void netmap_send_completed(NetClientState *nc, ssize_t len) static void netmap_send(void *opaque) { NetmapState *s = opaque; - struct netmap_ring *ring = s->me.rx; + struct netmap_ring *ring = s->rx; /* Keep sending while there are available packets into the netmap RX ring and the forwarding path towards the peer is open. */ @@ -349,10 +319,8 @@ static void netmap_cleanup(NetClientState *nc) qemu_purge_queued_packets(nc); netmap_poll(nc, false); - munmap(s->me.mem, s->me.memsize); - close(s->me.fd); - - s->me.fd = -1; + nm_close(s->nmd); + s->nmd = NULL; } /* Offloading manipulation support callbacks. */ @@ -383,17 +351,17 @@ static void netmap_set_vnet_hdr_len(NetClientState *nc, int len) struct nmreq req; /* Issue a NETMAP_BDG_VNET_HDR command to change the virtio-net header - * length for the netmap adapter associated to 'me->ifname'. + * length for the netmap adapter associated to 's->ifname'. */ memset(&req, 0, sizeof(req)); - pstrcpy(req.nr_name, sizeof(req.nr_name), s->me.ifname); + pstrcpy(req.nr_name, sizeof(req.nr_name), s->ifname); req.nr_version = NETMAP_API; req.nr_cmd = NETMAP_BDG_VNET_HDR; req.nr_arg1 = len; - err = ioctl(s->me.fd, NIOCREGIF, &req); + err = ioctl(s->nmd->fd, NIOCREGIF, &req); if (err) { error_report("Unable to execute NETMAP_BDG_VNET_HDR on %s: %s", - s->me.ifname, strerror(errno)); + s->ifname, strerror(errno)); } else { /* Keep track of the current length. */ s->vnet_hdr_len = len; @@ -437,16 +405,12 @@ int net_init_netmap(const NetClientOptions *opts, const char *name, NetClientState *peer, Error **errp) { const NetdevNetmapOptions *netmap_opts = opts->u.netmap; + struct nm_desc *nmd; NetClientState *nc; Error *err = NULL; - NetmapPriv me; NetmapState *s; - pstrcpy(me.fdname, sizeof(me.fdname), - netmap_opts->has_devname ? netmap_opts->devname : "/dev/netmap"); - /* Set default name for the port if not supplied. */ - pstrcpy(me.ifname, sizeof(me.ifname), netmap_opts->ifname); - netmap_open(&me, &err); + nmd = netmap_open(netmap_opts, &err); if (err) { error_propagate(errp, err); return -1; @@ -454,8 +418,11 @@ int net_init_netmap(const NetClientOptions *opts, /* Create the object. */ nc = qemu_new_net_client(&net_netmap_info, peer, "netmap", name); s = DO_UPCAST(NetmapState, nc, nc); - s->me = me; + s->nmd = nmd; + s->tx = NETMAP_TXRING(nmd->nifp, 0); + s->rx = NETMAP_RXRING(nmd->nifp, 0); s->vnet_hdr_len = 0; + pstrcpy(s->ifname, sizeof(s->ifname), netmap_opts->ifname); netmap_read_poll(s, true); /* Initially only poll for reads. */ return 0; -- 2.5.0