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-rw-r--r--hw/9pfs/9p.h6
-rw-r--r--hw/9pfs/Makefile.objs1
-rw-r--r--hw/9pfs/virtio-9p-device.c6
-rw-r--r--hw/9pfs/xen-9p-backend.c440
-rw-r--r--hw/9pfs/xen-9pfs.h21
5 files changed, 469 insertions, 5 deletions
diff --git a/hw/9pfs/9p.h b/hw/9pfs/9p.h
index b7e836251e..5312d8a424 100644
--- a/hw/9pfs/9p.h
+++ b/hw/9pfs/9p.h
@@ -119,6 +119,12 @@ static inline char *rpath(FsContext *ctx, const char *path)
typedef struct V9fsPDU V9fsPDU;
struct V9fsState;
+typedef struct {
+ uint32_t size_le;
+ uint8_t id;
+ uint16_t tag_le;
+} QEMU_PACKED P9MsgHeader;
+
struct V9fsPDU
{
uint32_t size;
diff --git a/hw/9pfs/Makefile.objs b/hw/9pfs/Makefile.objs
index 32197e6671..cab5e942ed 100644
--- a/hw/9pfs/Makefile.objs
+++ b/hw/9pfs/Makefile.objs
@@ -5,5 +5,6 @@ common-obj-y += coth.o cofs.o codir.o cofile.o
common-obj-y += coxattr.o 9p-synth.o
common-obj-$(CONFIG_OPEN_BY_HANDLE) += 9p-handle.o
common-obj-y += 9p-proxy.o
+common-obj-$(CONFIG_XEN) += xen-9p-backend.o
obj-y += virtio-9p-device.o
diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c
index 27a4a32f5c..3782f43702 100644
--- a/hw/9pfs/virtio-9p-device.c
+++ b/hw/9pfs/virtio-9p-device.c
@@ -46,11 +46,7 @@ static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq)
VirtQueueElement *elem;
while ((pdu = pdu_alloc(s))) {
- struct {
- uint32_t size_le;
- uint8_t id;
- uint16_t tag_le;
- } QEMU_PACKED out;
+ P9MsgHeader out;
elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
if (!elem) {
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
new file mode 100644
index 0000000000..9c7f41af99
--- /dev/null
+++ b/hw/9pfs/xen-9p-backend.c
@@ -0,0 +1,440 @@
+/*
+ * Xen 9p backend
+ *
+ * Copyright Aporeto 2017
+ *
+ * Authors:
+ * Stefano Stabellini <stefano@aporeto.com>
+ *
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/hw.h"
+#include "hw/9pfs/9p.h"
+#include "hw/xen/xen_backend.h"
+#include "hw/9pfs/xen-9pfs.h"
+#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 void xen_9pfs_in_sg(Xen9pfsRing *ring,
+ struct iovec *in_sg,
+ int *num,
+ uint32_t idx,
+ uint32_t size)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->in_cons;
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_FLEX_RING_SIZE(ring->ring_order));
+ masked_cons = xen_9pfs_mask(cons, XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ if (masked_prod < masked_cons) {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = masked_cons - masked_prod;
+ *num = 1;
+ } else {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = XEN_FLEX_RING_SIZE(ring->ring_order) - masked_prod;
+ in_sg[1].iov_base = ring->ring.in;
+ in_sg[1].iov_len = masked_cons;
+ *num = 2;
+ }
+}
+
+static void xen_9pfs_out_sg(Xen9pfsRing *ring,
+ struct iovec *out_sg,
+ int *num,
+ uint32_t idx)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_FLEX_RING_SIZE(ring->ring_order));
+ masked_cons = xen_9pfs_mask(cons, XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ if (masked_cons < masked_prod) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ } else {
+ if (ring->out_size >
+ (XEN_FLEX_RING_SIZE(ring->ring_order) - masked_cons)) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = XEN_FLEX_RING_SIZE(ring->ring_order) -
+ masked_cons;
+ out_sg[1].iov_base = ring->ring.out;
+ out_sg[1].iov_len = ring->out_size -
+ (XEN_FLEX_RING_SIZE(ring->ring_order) -
+ masked_cons);
+ *num = 2;
+ } else {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ }
+ }
+}
+
+static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ Xen9pfsDev *xen_9pfs = container_of(pdu->s, Xen9pfsDev, state);
+ struct iovec in_sg[2];
+ int num;
+
+ xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
+ return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
+}
+
+static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ Xen9pfsDev *xen_9pfs = container_of(pdu->s, Xen9pfsDev, state);
+ struct iovec out_sg[2];
+ int num;
+
+ xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ out_sg, &num, pdu->idx);
+ return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
+}
+
+static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov)
+{
+ Xen9pfsDev *xen_9pfs = container_of(pdu->s, Xen9pfsDev, state);
+ Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ int num;
+
+ g_free(ring->sg);
+
+ ring->sg = g_malloc0(sizeof(*ring->sg) * 2);
+ xen_9pfs_out_sg(ring, ring->sg, &num, pdu->idx);
+ *piov = ring->sg;
+ *pniov = num;
+}
+
+static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov,
+ size_t size)
+{
+ Xen9pfsDev *xen_9pfs = container_of(pdu->s, Xen9pfsDev, state);
+ Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ int num;
+
+ g_free(ring->sg);
+
+ ring->sg = g_malloc0(sizeof(*ring->sg) * 2);
+ xen_9pfs_in_sg(ring, ring->sg, &num, pdu->idx, size);
+ *piov = ring->sg;
+ *pniov = num;
+}
+
+static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
+{
+ RING_IDX prod;
+ Xen9pfsDev *priv = container_of(pdu->s, Xen9pfsDev, state);
+ Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
+
+ g_free(ring->sg);
+ ring->sg = NULL;
+
+ ring->intf->out_cons = ring->out_cons;
+ xen_wmb();
+
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ ring->intf->in_prod = prod + pdu->size;
+ xen_wmb();
+
+ ring->inprogress = false;
+ xenevtchn_notify(ring->evtchndev, ring->local_port);
+
+ qemu_bh_schedule(ring->bh);
+}
+
+static const struct V9fsTransport xen_9p_transport = {
+ .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
+ .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
+ .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
+ .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
+ .push_and_notify = xen_9pfs_push_and_notify,
+};
+
+static int xen_9pfs_init(struct XenDevice *xendev)
+{
+ return 0;
+}
+
+static int xen_9pfs_receive(Xen9pfsRing *ring)
+{
+ P9MsgHeader h;
+ RING_IDX cons, prod, masked_prod, masked_cons;
+ V9fsPDU *pdu;
+
+ if (ring->inprogress) {
+ return 0;
+ }
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+
+ if (xen_9pfs_queued(prod, cons, XEN_FLEX_RING_SIZE(ring->ring_order)) <
+ sizeof(h)) {
+ return 0;
+ }
+ ring->inprogress = true;
+
+ masked_prod = xen_9pfs_mask(prod, XEN_FLEX_RING_SIZE(ring->ring_order));
+ masked_cons = xen_9pfs_mask(cons, XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ xen_9pfs_read_packet((uint8_t *) &h, ring->ring.out, sizeof(h),
+ masked_prod, &masked_cons,
+ XEN_FLEX_RING_SIZE(ring->ring_order));
+
+ /* cannot fail, because we only handle one request per ring at a time */
+ pdu = pdu_alloc(&ring->priv->state);
+ pdu->size = le32_to_cpu(h.size_le);
+ pdu->id = h.id;
+ pdu->tag = le32_to_cpu(h.tag_le);
+ ring->out_size = le32_to_cpu(h.size_le);
+ ring->out_cons = cons + le32_to_cpu(h.size_le);
+
+ qemu_co_queue_init(&pdu->complete);
+ pdu_submit(pdu);
+
+ return 0;
+}
+
+static void xen_9pfs_bh(void *opaque)
+{
+ Xen9pfsRing *ring = opaque;
+ xen_9pfs_receive(ring);
+}
+
+static void xen_9pfs_evtchn_event(void *opaque)
+{
+ Xen9pfsRing *ring = opaque;
+ evtchn_port_t port;
+
+ port = xenevtchn_pending(ring->evtchndev);
+ xenevtchn_unmask(ring->evtchndev, port);
+
+ qemu_bh_schedule(ring->bh);
+}
+
+static int xen_9pfs_free(struct XenDevice *xendev)
+{
+ 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 = {
+ .size = sizeof(Xen9pfsDev),
+ .flags = DEVOPS_FLAG_NEED_GNTDEV,
+ .alloc = xen_9pfs_alloc,
+ .init = xen_9pfs_init,
+ .initialise = xen_9pfs_connect,
+ .disconnect = xen_9pfs_disconnect,
+ .free = xen_9pfs_free,
+};
diff --git a/hw/9pfs/xen-9pfs.h b/hw/9pfs/xen-9pfs.h
new file mode 100644
index 0000000000..2d6ef7828c
--- /dev/null
+++ b/hw/9pfs/xen-9pfs.h
@@ -0,0 +1,21 @@
+/*
+ * Xen 9p backend
+ *
+ * Copyright Aporeto 2017
+ *
+ * Authors:
+ * Stefano Stabellini <stefano@aporeto.com>
+ *
+ * This work is licensed under the terms of the GNU GPL version 2 or
+ * later. See the COPYING file in the top-level directory.
+ *
+ */
+
+#include <xen/io/protocols.h>
+#include "hw/xen/io/ring.h"
+
+/*
+ * Do not merge into xen-9p-backend.c: clang doesn't allow unused static
+ * inline functions in c files.
+ */
+DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-25 05:39:12 +0000