On Mon, 13 Mar 2017 16:55:56 -0700 Stefano Stabellini wrote: > Write the limits of the backend to xenstore. Connect to the frontend. > Upon connection, allocate the rings according to the protocol > specification. > > Initialize a QEMUBH to schedule work upon receiving an event channel > notification from the frontend. > > Signed-off-by: Stefano Stabellini > CC: anthony.perard@citrix.com > CC: jgross@suse.com > CC: Aneesh Kumar K.V > CC: Greg Kurz > --- > hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 158 insertions(+), 1 deletion(-) > > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c > index 35032d3..0e4a133 100644 > --- a/hw/9pfs/xen-9p-backend.c > +++ b/hw/9pfs/xen-9p-backend.c > @@ -17,8 +17,35 @@ > #include "qemu/config-file.h" > #include "fsdev/qemu-fsdev.h" > > +#define VERSIONS "1" > +#define MAX_RINGS 8 > +#define MAX_RING_ORDER 8 > + > +struct Xen9pfsRing { > + struct Xen9pfsDev *priv; > + > + int ref; > + xenevtchn_handle *evtchndev; > + int evtchn; > + int local_port; > + struct xen_9pfs_data_intf *intf; > + unsigned char *data; > + struct xen_9pfs_data ring; > + > + QEMUBH *bh; > + > + /* local copies, so that we can read/write PDU data directly from > + * the ring */ > + RING_IDX out_cons, out_size, in_cons; > + bool inprogress; > +}; > + QEMU Coding style requires a typedef. FWIW, maybe you could also convert other structured types like XenDevice or XenDevOps. > typedef struct Xen9pfsDev { > struct XenDevice xendev; /* must be first */ > + V9fsState state; > + > + int num_rings; > + struct Xen9pfsRing *rings; > } Xen9pfsDev; > > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu, > @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev) > return 0; > } > > +static void xen_9pfs_bh(void *opaque) > +{ > +} > + > +static void xen_9pfs_evtchn_event(void *opaque) > +{ > +} > + > static int xen_9pfs_free(struct XenDevice *xendev) > { > - return -1; > + int i; > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev); > + Coding style. > + for (i = 0; i < xen_9pdev->num_rings; i++) { > + if (xen_9pdev->rings[i].data != NULL) { > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev, > + xen_9pdev->rings[i].data, > + (1 << XEN_9PFS_RING_ORDER)); > + } > + if (xen_9pdev->rings[i].intf != NULL) { > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev, > + xen_9pdev->rings[i].intf, > + 1); > + } > + if (xen_9pdev->rings[i].evtchndev > 0) { > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), > + NULL, NULL, NULL); > + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port); > + } > + if (xen_9pdev->rings[i].bh != NULL) { > + qemu_bh_delete(xen_9pdev->rings[i].bh); > + } > + } > + g_free(xen_9pdev->rings); > + return 0; > } > > static int xen_9pfs_connect(struct XenDevice *xendev) > { > + int i; > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev); Coding style. > + V9fsState *s = &xen_9pdev->state; > + QemuOpts *fsdev; > + char *security_model, *path; > + > + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings", > + &xen_9pdev->num_rings) == -1 || > + xen_9pdev->num_rings > MAX_RINGS) { > + return -1; > + } > + > + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing)); > + for (i = 0; i < xen_9pdev->num_rings; i++) { > + char str[16]; > + > + xen_9pdev->rings[i].priv = xen_9pdev; > + xen_9pdev->rings[i].evtchn = -1; > + xen_9pdev->rings[i].local_port = -1; > + > + sprintf(str, "ring-ref%u", i); > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str, > + &xen_9pdev->rings[i].ref) == -1) { > + goto out; > + } > + sprintf(str, "event-channel-%u", i); > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str, > + &xen_9pdev->rings[i].evtchn) == -1) { > + goto out; > + } > + > + xen_9pdev->rings[i].intf = xengnttab_map_grant_ref( > + xen_9pdev->xendev.gnttabdev, > + xen_9pdev->xendev.dom, > + xen_9pdev->rings[i].ref, > + PROT_READ | PROT_WRITE); > + if (!xen_9pdev->rings[i].intf) { > + goto out; > + } > + xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs( > + xen_9pdev->xendev.gnttabdev, > + (1 << XEN_9PFS_RING_ORDER), > + xen_9pdev->xendev.dom, > + xen_9pdev->rings[i].intf->ref, > + PROT_READ | PROT_WRITE); > + if (!xen_9pdev->rings[i].data) { > + goto out; > + } > + xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data; > + xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE; > + > + xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]); > + xen_9pdev->rings[i].out_cons = 0; > + xen_9pdev->rings[i].out_size = 0; > + xen_9pdev->rings[i].inprogress = false; > + > + > + xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0); > + if (xen_9pdev->rings[i].evtchndev == NULL) { > + goto out; > + } > + fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC); > + xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain > + (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn); > + if (xen_9pdev->rings[i].local_port == -1) { > + xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n", > + xen_9pdev->rings[i].evtchn); > + goto out; > + } > + xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port); > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), > + xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]); > + } > + > + security_model = xenstore_read_be_str(xendev, "security_model"); > + path = xenstore_read_be_str(xendev, "path"); > + s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6); > + sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev); Please use g_strdup_printf(). > + s->fsconf.tag = xenstore_read_fe_str(xendev, "tag"); > + v9fs_register_transport(s, &xen_9p_transport); > + fsdev = qemu_opts_create(qemu_find_opts("fsdev"), > + s->fsconf.tag, > + 1, NULL); > + qemu_opt_set(fsdev, "fsdriver", "local", NULL); > + qemu_opt_set(fsdev, "path", path, NULL); > + qemu_opt_set(fsdev, "security_model", security_model, NULL); > + qemu_opts_set_id(fsdev, s->fsconf.fsdev_id); > + qemu_fsdev_add(fsdev); > + v9fs_device_realize_common(s, NULL); > + > return 0; > + > +out: > + xen_9pfs_free(xendev); > + return -1; > } > > static void xen_9pfs_alloc(struct XenDevice *xendev) > { > + xenstore_write_be_str(xendev, "versions", VERSIONS); > + xenstore_write_be_int(xendev, "max-rings", MAX_RINGS); > + xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER); > } > > static void xen_9pfs_disconnect(struct XenDevice *xendev) > { > + /* Dynamic hotplug of PV filesystems at runtime is not supported. */ Does this mean that this function is never called ? Or that it should report an error ? Or print one ? In any case, it looks weird that it doesn't free the fsdev_id that was allocated in xen_9pfs_connect(). > } > > struct XenDevOps xen_9pfs_ops = {