@@ -17,8 +17,41 @@
#include "qemu/config-file.h"
#include "fsdev/qemu-fsdev.h"
+#define VERSIONS "1"
+#define MAX_RINGS 8
+#define MAX_RING_ORDER 8
+
+typedef struct Xen9pfsRing {
+ struct Xen9pfsDev *priv;
+
+ int ref;
+ xenevtchn_handle *evtchndev;
+ int evtchn;
+ int local_port;
+ int ring_order;
+ struct xen_9pfs_data_intf *intf;
+ unsigned char *data;
+ struct xen_9pfs_data ring;
+
+ struct iovec *sg;
+ 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;
+} Xen9pfsRing;
+
typedef struct Xen9pfsDev {
struct XenDevice xendev; /* must be first */
+ V9fsState state;
+ char *path;
+ char *security_model;
+ char *tag;
+ char *id;
+
+ int num_rings;
+ Xen9pfsRing *rings;
} Xen9pfsDev;
static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
@@ -67,22 +100,169 @@ 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;
+ Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
+
+ g_free(xen_9pdev->id);
+ g_free(xen_9pdev->tag);
+ g_free(xen_9pdev->path);
+ g_free(xen_9pdev->security_model);
+
+ 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_9pdev->rings[i].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;
+ Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
+ V9fsState *s = &xen_9pdev->state;
+ QemuOpts *fsdev;
+
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
+ &xen_9pdev->num_rings) == -1 ||
+ xen_9pdev->num_rings > MAX_RINGS || xen_9pdev->num_rings < 1) {
+ return -1;
+ }
+
+ xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(Xen9pfsRing));
+ for (i = 0; i < xen_9pdev->num_rings; i++) {
+ char *str;
+ int ring_order;
+
+ xen_9pdev->rings[i].priv = xen_9pdev;
+ xen_9pdev->rings[i].evtchn = -1;
+ xen_9pdev->rings[i].local_port = -1;
+
+ str = g_strdup_printf("ring-ref%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].ref) == -1) {
+ goto out;
+ }
+ g_free(str);
+ str = g_strdup_printf("event-channel-%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].evtchn) == -1) {
+ goto out;
+ }
+ g_free(str);
+
+ 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;
+ }
+ ring_order = xen_9pdev->rings[i].intf->ring_order;
+ if (ring_order > MAX_RING_ORDER) {
+ goto out;
+ }
+ xen_9pdev->rings[i].ring_order = ring_order;
+ xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
+ xen_9pdev->xendev.gnttabdev,
+ (1 << 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_FLEX_RING_SIZE(ring_order);
+
+ 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]);
+ }
+
+ xen_9pdev->security_model = xenstore_read_be_str(xendev, "security_model");
+ xen_9pdev->path = xenstore_read_be_str(xendev, "path");
+ xen_9pdev->id = s->fsconf.fsdev_id =
+ g_strdup_printf("xen9p%d", xendev->dev);
+ xen_9pdev->tag = 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", xen_9pdev->path, NULL);
+ qemu_opt_set(fsdev, "security_model", xen_9pdev->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. */
}
struct XenDevOps xen_9pfs_ops = {
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 <stefano@aporeto.com> CC: anthony.perard@citrix.com CC: jgross@suse.com CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> CC: Greg Kurz <groug@kaod.org> --- hw/9pfs/xen-9p-backend.c | 182 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 181 insertions(+), 1 deletion(-)