Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging

- transport specific callbacks (for Xen)
- fix crash (2.8 regression)
- 9p functional tests

# gpg: Signature made Tue 03 Jan 2017 17:30:58 GMT
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@fr.ibm.com>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "Gregory Kurz (Cimai Technology) <gkurz@cimai.com>"
# gpg:                 aka "Gregory Kurz (Meiosys Technology) <gkurz@meiosys.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  tests: virtio-9p: ".." cannot be used to walk out of the shared directory
  tests: virtio-9p: no slash in path elements during walk
  tests: virtio-9p: add walk operation test
  tests: virtio-9p: add attach operation test
  tests: virtio-9p: add version operation test
  9pfs: fix P9_NOTAG and P9_NOFID macros
  tests: virtio-9p: code refactoring
  tests: virtio-9p: rename PCI configuration test
  9pfs: fix crash when fsdev is missing
  9pfs: introduce init_out/in_iov_from_pdu
  9pfs: call v9fs_init_qiov_from_pdu before v9fs_pack
  9pfs: introduce transport specific callbacks
  9pfs: move pdus to V9fsState
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/9pfs/9p.c

@@ -47,7 +47,7 @@ ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
     va_list ap;
 
     va_start(ap, fmt);
-    ret = virtio_pdu_vmarshal(pdu, offset, fmt, ap);
+    ret = pdu->s->transport->pdu_vmarshal(pdu, offset, fmt, ap);
     va_end(ap);
 
     return ret;
@@ -59,7 +59,7 @@ ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
     va_list ap;
 
     va_start(ap, fmt);
-    ret = virtio_pdu_vunmarshal(pdu, offset, fmt, ap);
+    ret = pdu->s->transport->pdu_vunmarshal(pdu, offset, fmt, ap);
     va_end(ap);
 
     return ret;
@@ -67,7 +67,7 @@ ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
 
 static void pdu_push_and_notify(V9fsPDU *pdu)
 {
-    virtio_9p_push_and_notify(pdu);
+    pdu->s->transport->push_and_notify(pdu);
 }
 
 static int omode_to_uflags(int8_t mode)
@@ -1633,14 +1633,43 @@ out_nofid:
     pdu_complete(pdu, err);
 }
 
+/*
+ * Create a QEMUIOVector for a sub-region of PDU iovecs
+ *
+ * @qiov:       uninitialized QEMUIOVector
+ * @skip:       number of bytes to skip from beginning of PDU
+ * @size:       number of bytes to include
+ * @is_write:   true - write, false - read
+ *
+ * The resulting QEMUIOVector has heap-allocated iovecs and must be cleaned up
+ * with qemu_iovec_destroy().
+ */
+static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
+                                    size_t skip, size_t size,
+                                    bool is_write)
+{
+    QEMUIOVector elem;
+    struct iovec *iov;
+    unsigned int niov;
+
+    if (is_write) {
+        pdu->s->transport->init_out_iov_from_pdu(pdu, &iov, &niov);
+    } else {
+        pdu->s->transport->init_in_iov_from_pdu(pdu, &iov, &niov, size);
+    }
+
+    qemu_iovec_init_external(&elem, iov, niov);
+    qemu_iovec_init(qiov, niov);
+    qemu_iovec_concat(qiov, &elem, skip, size);
+}
+
 static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
                            uint64_t off, uint32_t max_count)
 {
     ssize_t err;
     size_t offset = 7;
     uint64_t read_count;
-    V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
-    VirtQueueElement *elem = v->elems[pdu->idx];
+    QEMUIOVector qiov_full;
 
     if (fidp->fs.xattr.len < off) {
         read_count = 0;
@@ -1656,9 +1685,11 @@ static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
     }
     offset += err;
 
-    err = v9fs_pack(elem->in_sg, elem->in_num, offset,
+    v9fs_init_qiov_from_pdu(&qiov_full, pdu, 0, read_count, false);
+    err = v9fs_pack(qiov_full.iov, qiov_full.niov, offset,
                     ((char *)fidp->fs.xattr.value) + off,
                     read_count);
+    qemu_iovec_destroy(&qiov_full);
     if (err < 0) {
         return err;
     }
@@ -1732,32 +1763,6 @@ static int coroutine_fn v9fs_do_readdir_with_stat(V9fsPDU *pdu,
     return count;
 }
 
-/*
- * Create a QEMUIOVector for a sub-region of PDU iovecs
- *
- * @qiov:       uninitialized QEMUIOVector
- * @skip:       number of bytes to skip from beginning of PDU
- * @size:       number of bytes to include
- * @is_write:   true - write, false - read
- *
- * The resulting QEMUIOVector has heap-allocated iovecs and must be cleaned up
- * with qemu_iovec_destroy().
- */
-static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
-                                    size_t skip, size_t size,
-                                    bool is_write)
-{
-    QEMUIOVector elem;
-    struct iovec *iov;
-    unsigned int niov;
-
-    virtio_init_iov_from_pdu(pdu, &iov, &niov, is_write);
-
-    qemu_iovec_init_external(&elem, iov, niov);
-    qemu_iovec_init(qiov, niov);
-    qemu_iovec_concat(qiov, &elem, skip, size);
-}
-
 static void coroutine_fn v9fs_read(void *opaque)
 {
     int32_t fid;
@@ -3440,7 +3445,6 @@ void pdu_submit(V9fsPDU *pdu)
 /* Returns 0 on success, 1 on failure. */
 int v9fs_device_realize_common(V9fsState *s, Error **errp)
 {
-    V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
     int i, len;
     struct stat stat;
     FsDriverEntry *fse;
@@ -3451,9 +3455,9 @@ int v9fs_device_realize_common(V9fsState *s, Error **errp)
     QLIST_INIT(&s->free_list);
     QLIST_INIT(&s->active_list);
     for (i = 0; i < (MAX_REQ - 1); i++) {
-        QLIST_INSERT_HEAD(&s->free_list, &v->pdus[i], next);
-        v->pdus[i].s = s;
-        v->pdus[i].idx = i;
+        QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
+        s->pdus[i].s = s;
+        s->pdus[i].idx = i;
     }
 
     v9fs_path_init(&path);
@@ -3521,7 +3525,7 @@ int v9fs_device_realize_common(V9fsState *s, Error **errp)
     rc = 0;
 out:
     if (rc) {
-        if (s->ops->cleanup && s->ctx.private) {
+        if (s->ops && s->ops->cleanup && s->ctx.private) {
             s->ops->cleanup(&s->ctx);
         }
         g_free(s->tag);

hw/9pfs/9p.h

@@ -99,8 +99,8 @@ enum p9_proto_version {
     V9FS_PROTO_2000L = 0x02,
 };
 
-#define P9_NOTAG    (u16)(~0)
-#define P9_NOFID    (u32)(~0)
+#define P9_NOTAG    UINT16_MAX
+#define P9_NOFID    UINT32_MAX
 #define P9_MAXWELEM 16
 
 #define FID_REFERENCED          0x1
@@ -229,6 +229,8 @@ typedef struct V9fsState
     char *tag;
     enum p9_proto_version proto_version;
     int32_t msize;
+    V9fsPDU pdus[MAX_REQ];
+    const struct V9fsTransport *transport;
     /*
      * lock ensuring atomic path update
      * on rename.
@@ -342,4 +344,24 @@ void pdu_free(V9fsPDU *pdu);
 void pdu_submit(V9fsPDU *pdu);
 void v9fs_reset(V9fsState *s);
 
+struct V9fsTransport {
+    ssize_t     (*pdu_vmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
+                                va_list ap);
+    ssize_t     (*pdu_vunmarshal)(V9fsPDU *pdu, size_t offset, const char *fmt,
+                                  va_list ap);
+    void        (*init_in_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
+                                        unsigned int *pniov, size_t size);
+    void        (*init_out_iov_from_pdu)(V9fsPDU *pdu, struct iovec **piov,
+                                         unsigned int *pniov);
+    void        (*push_and_notify)(V9fsPDU *pdu);
+};
+
+static inline int v9fs_register_transport(V9fsState *s,
+        const struct V9fsTransport *t)
+{
+    assert(!s->transport);
+    s->transport = t;
+    return 0;
+}
+
 #endif

hw/9pfs/virtio-9p-device.c

@@ -20,7 +20,9 @@
 #include "hw/virtio/virtio-access.h"
 #include "qemu/iov.h"
 
-void virtio_9p_push_and_notify(V9fsPDU *pdu)
+static const struct V9fsTransport virtio_9p_transport;
+
+static void virtio_9p_push_and_notify(V9fsPDU *pdu)
 {
     V9fsState *s = pdu->s;
     V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
@@ -126,6 +128,7 @@ static void virtio_9p_device_realize(DeviceState *dev, Error **errp)
     v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag);
     virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size);
     v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
+    v9fs_register_transport(s, &virtio_9p_transport);
 
 out:
     return;
@@ -148,8 +151,8 @@ static void virtio_9p_reset(VirtIODevice *vdev)
     v9fs_reset(&v->state);
 }
 
-ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
-                            const char *fmt, va_list ap)
+static ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
+                                   const char *fmt, va_list ap)
 {
     V9fsState *s = pdu->s;
     V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
@@ -158,8 +161,8 @@ ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
     return v9fs_iov_vmarshal(elem->in_sg, elem->in_num, offset, 1, fmt, ap);
 }
 
-ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
-                              const char *fmt, va_list ap)
+static ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
+                                     const char *fmt, va_list ap)
 {
     V9fsState *s = pdu->s;
     V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
@@ -168,22 +171,37 @@ ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
     return v9fs_iov_vunmarshal(elem->out_sg, elem->out_num, offset, 1, fmt, ap);
 }
 
-void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
-                              unsigned int *pniov, bool is_write)
+/* The size parameter is used by other transports. Do not drop it. */
+static void virtio_init_in_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
+                                        unsigned int *pniov, size_t size)
 {
     V9fsState *s = pdu->s;
     V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
     VirtQueueElement *elem = v->elems[pdu->idx];
 
-    if (is_write) {
-        *piov = elem->out_sg;
-        *pniov = elem->out_num;
-    } else {
-        *piov = elem->in_sg;
-        *pniov = elem->in_num;
-    }
+    *piov = elem->in_sg;
+    *pniov = elem->in_num;
 }
 
+static void virtio_init_out_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
+                                         unsigned int *pniov)
+{
+    V9fsState *s = pdu->s;
+    V9fsVirtioState *v = container_of(s, V9fsVirtioState, state);
+    VirtQueueElement *elem = v->elems[pdu->idx];
+
+    *piov = elem->out_sg;
+    *pniov = elem->out_num;
+}
+
+static const struct V9fsTransport virtio_9p_transport = {
+    .pdu_vmarshal = virtio_pdu_vmarshal,
+    .pdu_vunmarshal = virtio_pdu_vunmarshal,
+    .init_in_iov_from_pdu = virtio_init_in_iov_from_pdu,
+    .init_out_iov_from_pdu = virtio_init_out_iov_from_pdu,
+    .push_and_notify = virtio_9p_push_and_notify,
+};
+
 /* virtio-9p device */
 
 static const VMStateDescription vmstate_virtio_9p = {

hw/9pfs/virtio-9p.h

@@ -10,20 +10,10 @@ typedef struct V9fsVirtioState
     VirtIODevice parent_obj;
     VirtQueue *vq;
     size_t config_size;
-    V9fsPDU pdus[MAX_REQ];
     VirtQueueElement *elems[MAX_REQ];
     V9fsState state;
 } V9fsVirtioState;
 
-void virtio_9p_push_and_notify(V9fsPDU *pdu);
-
-ssize_t virtio_pdu_vmarshal(V9fsPDU *pdu, size_t offset,
-                            const char *fmt, va_list ap);
-ssize_t virtio_pdu_vunmarshal(V9fsPDU *pdu, size_t offset,
-                              const char *fmt, va_list ap);
-void virtio_init_iov_from_pdu(V9fsPDU *pdu, struct iovec **piov,
-                              unsigned int *pniov, bool is_write);
-
 #define TYPE_VIRTIO_9P "virtio-9p-device"
 #define VIRTIO_9P(obj) \
         OBJECT_CHECK(V9fsVirtioState, (obj), TYPE_VIRTIO_9P)

tests/virtio-9p-test.c

@@ -16,61 +16,53 @@
 #include "libqos/virtio-pci.h"
 #include "standard-headers/linux/virtio_ids.h"
 #include "standard-headers/linux/virtio_pci.h"
+#include "hw/9pfs/9p.h"
 
 static const char mount_tag[] = "qtest";
-static char *test_share;
 
+typedef struct {
+    QVirtioDevice *dev;
+    QOSState *qs;
+    QVirtQueue *vq;
+    char *test_share;
+    uint16_t p9_req_tag;
+} QVirtIO9P;
 
-static QOSState *qvirtio_9p_start(void)
+static QVirtIO9P *qvirtio_9p_start(const char *driver)
 {
     const char *arch = qtest_get_arch();
     const char *cmd = "-fsdev local,id=fsdev0,security_model=none,path=%s "
-                      "-device virtio-9p-pci,fsdev=fsdev0,mount_tag=%s";
+                      "-device %s,fsdev=fsdev0,mount_tag=%s";
+    QVirtIO9P *v9p = g_new0(QVirtIO9P, 1);
 
-    test_share = g_strdup("/tmp/qtest.XXXXXX");
-    g_assert_nonnull(mkdtemp(test_share));
+    v9p->test_share = g_strdup("/tmp/qtest.XXXXXX");
+    g_assert_nonnull(mkdtemp(v9p->test_share));
 
     if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
-        return qtest_pc_boot(cmd, test_share, mount_tag);
-    }
-    if (strcmp(arch, "ppc64") == 0) {
-        return qtest_spapr_boot(cmd, test_share, mount_tag);
+        v9p->qs = qtest_pc_boot(cmd, v9p->test_share, driver, mount_tag);
+    } else if (strcmp(arch, "ppc64") == 0) {
+        v9p->qs = qtest_spapr_boot(cmd, v9p->test_share, driver, mount_tag);
+    } else {
+        g_printerr("virtio-9p tests are only available on x86 or ppc64\n");
+        exit(EXIT_FAILURE);
     }
 
-    g_printerr("virtio-9p tests are only available on x86 or ppc64\n");
-    exit(EXIT_FAILURE);
-}
-
-static void qvirtio_9p_stop(QOSState *qs)
-{
-    qtest_shutdown(qs);
-    rmdir(test_share);
-    g_free(test_share);
+    return v9p;
 }
 
-static void pci_nop(void)
+static void qvirtio_9p_stop(QVirtIO9P *v9p)
 {
-    QOSState *qs;
-
-    qs = qvirtio_9p_start();
-    qvirtio_9p_stop(qs);
+    qtest_shutdown(v9p->qs);
+    rmdir(v9p->test_share);
+    g_free(v9p->test_share);
+    g_free(v9p);
 }
 
-typedef struct {
-    QVirtioDevice *dev;
-    QOSState *qs;
-    QVirtQueue *vq;
-} QVirtIO9P;
-
-static QVirtIO9P *qvirtio_9p_pci_init(QOSState *qs)
+static QVirtIO9P *qvirtio_9p_pci_start(void)
 {
-    QVirtIO9P *v9p;
-    QVirtioPCIDevice *dev;
-
-    v9p = g_new0(QVirtIO9P, 1);
-
-    v9p->qs = qs;
-    dev = qvirtio_pci_device_find(v9p->qs->pcibus, VIRTIO_ID_9P);
+    QVirtIO9P *v9p = qvirtio_9p_start("virtio-9p-pci");
+    QVirtioPCIDevice *dev = qvirtio_pci_device_find(v9p->qs->pcibus,
+                                                    VIRTIO_ID_9P);
     g_assert_nonnull(dev);
     g_assert_cmphex(dev->vdev.device_type, ==, VIRTIO_ID_9P);
     v9p->dev = (QVirtioDevice *) dev;
@@ -84,26 +76,20 @@ static QVirtIO9P *qvirtio_9p_pci_init(QOSState *qs)
     return v9p;
 }
 
-static void qvirtio_9p_pci_free(QVirtIO9P *v9p)
+static void qvirtio_9p_pci_stop(QVirtIO9P *v9p)
 {
     qvirtqueue_cleanup(v9p->dev->bus, v9p->vq, v9p->qs->alloc);
     qvirtio_pci_device_disable(container_of(v9p->dev, QVirtioPCIDevice, vdev));
     g_free(v9p->dev);
-    g_free(v9p);
+    qvirtio_9p_stop(v9p);
 }
 
-static void pci_basic_config(void)
+static void pci_config(QVirtIO9P *v9p)
 {
-    QVirtIO9P *v9p;
-    size_t tag_len;
+    size_t tag_len = qvirtio_config_readw(v9p->dev, 0);
     char *tag;
     int i;
-    QOSState *qs;
 
-    qs = qvirtio_9p_start();
-    v9p = qvirtio_9p_pci_init(qs);
-
-    tag_len = qvirtio_config_readw(v9p->dev, 0);
     g_assert_cmpint(tag_len, ==, strlen(mount_tag));
 
     tag = g_malloc(tag_len);
@@ -112,16 +98,406 @@ static void pci_basic_config(void)
     }
     g_assert_cmpmem(tag, tag_len, mount_tag, tag_len);
     g_free(tag);
+}
+
+#define P9_MAX_SIZE 4096 /* Max size of a T-message or R-message */
+
+typedef struct {
+    QVirtIO9P *v9p;
+    uint16_t tag;
+    uint64_t t_msg;
+    uint32_t t_size;
+    uint64_t r_msg;
+    /* No r_size, it is hardcoded to P9_MAX_SIZE */
+    size_t t_off;
+    size_t r_off;
+} P9Req;
+
+static void v9fs_memwrite(P9Req *req, const void *addr, size_t len)
+{
+    memwrite(req->t_msg + req->t_off, addr, len);
+    req->t_off += len;
+}
+
+static void v9fs_memskip(P9Req *req, size_t len)
+{
+    req->r_off += len;
+}
+
+static void v9fs_memrewind(P9Req *req, size_t len)
+{
+    req->r_off -= len;
+}
+
+static void v9fs_memread(P9Req *req, void *addr, size_t len)
+{
+    memread(req->r_msg + req->r_off, addr, len);
+    req->r_off += len;
+}
+
+static void v9fs_uint16_write(P9Req *req, uint16_t val)
+{
+    uint16_t le_val = cpu_to_le16(val);
+
+    v9fs_memwrite(req, &le_val, 2);
+}
+
+static void v9fs_uint16_read(P9Req *req, uint16_t *val)
+{
+    v9fs_memread(req, val, 2);
+    le16_to_cpus(val);
+}
+
+static void v9fs_uint32_write(P9Req *req, uint32_t val)
+{
+    uint32_t le_val = cpu_to_le32(val);
+
+    v9fs_memwrite(req, &le_val, 4);
+}
+
+static void v9fs_uint32_read(P9Req *req, uint32_t *val)
+{
+    v9fs_memread(req, val, 4);
+    le32_to_cpus(val);
+}
+
+/* len[2] string[len] */
+static uint16_t v9fs_string_size(const char *string)
+{
+    size_t len = strlen(string);
+
+    g_assert_cmpint(len, <=, UINT16_MAX);
+
+    return 2 + len;
+}
+
+static void v9fs_string_write(P9Req *req, const char *string)
+{
+    int len = strlen(string);
+
+    g_assert_cmpint(len, <=, UINT16_MAX);
+
+    v9fs_uint16_write(req, (uint16_t) len);
+    v9fs_memwrite(req, string, len);
+}
+
+static void v9fs_string_read(P9Req *req, uint16_t *len, char **string)
+{
+    uint16_t local_len;
+
+    v9fs_uint16_read(req, &local_len);
+    if (len) {
+        *len = local_len;
+    }
+    if (string) {
+        *string = g_malloc(local_len);
+        v9fs_memread(req, *string, local_len);
+    } else {
+        v9fs_memskip(req, local_len);
+    }
+}
+
+ typedef struct {
+    uint32_t size;
+    uint8_t id;
+    uint16_t tag;
+} QEMU_PACKED P9Hdr;
+
+static P9Req *v9fs_req_init(QVirtIO9P *v9p, uint32_t size, uint8_t id,
+                            uint16_t tag)
+{
+    P9Req *req = g_new0(P9Req, 1);
+    uint32_t t_size = 7 + size; /* 9P header has well-known size of 7 bytes */
+    P9Hdr hdr = {
+        .size = cpu_to_le32(t_size),
+        .id = id,
+        .tag = cpu_to_le16(tag)
+    };
+
+    g_assert_cmpint(t_size, <=, P9_MAX_SIZE);
 
-    qvirtio_9p_pci_free(v9p);
-    qvirtio_9p_stop(qs);
+    req->v9p = v9p;
+    req->t_size = t_size;
+    req->t_msg = guest_alloc(v9p->qs->alloc, req->t_size);
+    v9fs_memwrite(req, &hdr, 7);
+    req->tag = tag;
+    return req;
+}
+
+static void v9fs_req_send(P9Req *req)
+{
+    QVirtIO9P *v9p = req->v9p;
+    uint32_t free_head;
+
+    req->r_msg = guest_alloc(v9p->qs->alloc, P9_MAX_SIZE);
+    free_head = qvirtqueue_add(v9p->vq, req->t_msg, req->t_size, false, true);
+    qvirtqueue_add(v9p->vq, req->r_msg, P9_MAX_SIZE, true, false);
+    qvirtqueue_kick(v9p->dev, v9p->vq, free_head);
+    req->t_off = 0;
+}
+
+static void v9fs_req_recv(P9Req *req, uint8_t id)
+{
+    QVirtIO9P *v9p = req->v9p;
+    P9Hdr hdr;
+    int i;
+
+    for (i = 0; i < 10; i++) {
+        qvirtio_wait_queue_isr(v9p->dev, v9p->vq, 1000 * 1000);
+
+        v9fs_memread(req, &hdr, 7);
+        le32_to_cpus(&hdr.size);
+        le16_to_cpus(&hdr.tag);
+        if (hdr.size >= 7) {
+            break;
+        }
+        v9fs_memrewind(req, 7);
+    }
+
+    g_assert_cmpint(hdr.size, >=, 7);
+    g_assert_cmpint(hdr.size, <=, P9_MAX_SIZE);
+    g_assert_cmpint(hdr.tag, ==, req->tag);
+
+    if (hdr.id != id && hdr.id == P9_RLERROR) {
+        uint32_t err;
+        v9fs_uint32_read(req, &err);
+        g_printerr("Received Rlerror (%d) instead of Response %d\n", err, id);
+        g_assert_not_reached();
+    }
+    g_assert_cmpint(hdr.id, ==, id);
+}
+
+static void v9fs_req_free(P9Req *req)
+{
+    QVirtIO9P *v9p = req->v9p;
+
+    guest_free(v9p->qs->alloc, req->t_msg);
+    guest_free(v9p->qs->alloc, req->r_msg);
+    g_free(req);
+}
+
+/* size[4] Rlerror tag[2] ecode[4] */
+static void v9fs_rlerror(P9Req *req, uint32_t *err)
+{
+    v9fs_req_recv(req, P9_RLERROR);
+    v9fs_uint32_read(req, err);
+    v9fs_req_free(req);
+}
+
+/* size[4] Tversion tag[2] msize[4] version[s] */
+static P9Req *v9fs_tversion(QVirtIO9P *v9p, uint32_t msize, const char *version)
+{
+    P9Req *req = v9fs_req_init(v9p, 4 + v9fs_string_size(version), P9_TVERSION,
+                               P9_NOTAG);
+
+    v9fs_uint32_write(req, msize);
+    v9fs_string_write(req, version);
+    v9fs_req_send(req);
+    return req;
+}
+
+/* size[4] Rversion tag[2] msize[4] version[s] */
+static void v9fs_rversion(P9Req *req, uint16_t *len, char **version)
+{
+    uint32_t msize;
+
+    v9fs_req_recv(req, P9_RVERSION);
+    v9fs_uint32_read(req, &msize);
+
+    g_assert_cmpint(msize, ==, P9_MAX_SIZE);
+
+    if (len || version) {
+        v9fs_string_read(req, len, version);
+    }
+
+    v9fs_req_free(req);
+}
+
+/* size[4] Tattach tag[2] fid[4] afid[4] uname[s] aname[s] n_uname[4] */
+static P9Req *v9fs_tattach(QVirtIO9P *v9p, uint32_t fid, uint32_t n_uname)
+{
+    const char *uname = ""; /* ignored by QEMU */
+    const char *aname = ""; /* ignored by QEMU */
+    P9Req *req = v9fs_req_init(v9p, 4 + 4 + 2 + 2 + 4, P9_TATTACH,
+                               ++(v9p->p9_req_tag));
+
+    v9fs_uint32_write(req, fid);
+    v9fs_uint32_write(req, P9_NOFID);
+    v9fs_string_write(req, uname);
+    v9fs_string_write(req, aname);
+    v9fs_uint32_write(req, n_uname);
+    v9fs_req_send(req);
+    return req;
+}
+
+typedef char v9fs_qid[13];
+
+/* size[4] Rattach tag[2] qid[13] */
+static void v9fs_rattach(P9Req *req, v9fs_qid *qid)
+{
+    v9fs_req_recv(req, P9_RATTACH);
+    if (qid) {
+        v9fs_memread(req, qid, 13);
+    }
+    v9fs_req_free(req);
+}
+
+/* size[4] Twalk tag[2] fid[4] newfid[4] nwname[2] nwname*(wname[s]) */
+static P9Req *v9fs_twalk(QVirtIO9P *v9p, uint32_t fid, uint32_t newfid,
+                         uint16_t nwname, char *const wnames[])
+{
+    P9Req *req;
+    int i;
+    uint32_t size = 4 + 4 + 2;
+
+    for (i = 0; i < nwname; i++) {
+        size += v9fs_string_size(wnames[i]);
+    }
+    req = v9fs_req_init(v9p,  size, P9_TWALK, ++(v9p->p9_req_tag));
+    v9fs_uint32_write(req, fid);
+    v9fs_uint32_write(req, newfid);
+    v9fs_uint16_write(req, nwname);
+    for (i = 0; i < nwname; i++) {
+        v9fs_string_write(req, wnames[i]);
+    }
+    v9fs_req_send(req);
+    return req;
+}
+
+/* size[4] Rwalk tag[2] nwqid[2] nwqid*(wqid[13]) */
+static void v9fs_rwalk(P9Req *req, uint16_t *nwqid, v9fs_qid **wqid)
+{
+    uint16_t local_nwqid;
+
+    v9fs_req_recv(req, P9_RWALK);
+    v9fs_uint16_read(req, &local_nwqid);
+    if (nwqid) {
+        *nwqid = local_nwqid;
+    }
+    if (wqid) {
+        *wqid = g_malloc(local_nwqid * 13);
+        v9fs_memread(req, *wqid, local_nwqid * 13);
+    }
+    v9fs_req_free(req);
+}
+
+static void fs_version(QVirtIO9P *v9p)
+{
+    const char *version = "9P2000.L";
+    uint16_t server_len;
+    char *server_version;
+    P9Req *req;
+
+    req = v9fs_tversion(v9p, P9_MAX_SIZE, version);
+    v9fs_rversion(req, &server_len, &server_version);
+
+    g_assert_cmpmem(server_version, server_len, version, strlen(version));
+
+    g_free(server_version);
+}
+
+static void fs_attach(QVirtIO9P *v9p)
+{
+    P9Req *req;
+
+    fs_version(v9p);
+    req = v9fs_tattach(v9p, 0, getuid());
+    v9fs_rattach(req, NULL);
+}
+
+static void fs_walk(QVirtIO9P *v9p)
+{
+    char *wnames[P9_MAXWELEM], *paths[P9_MAXWELEM];
+    char *last_path = v9p->test_share;
+    uint16_t nwqid;
+    v9fs_qid *wqid;
+    int i;
+    P9Req *req;
+
+    for (i = 0; i < P9_MAXWELEM; i++) {
+        wnames[i] = g_strdup_printf("%s%d", __func__, i);
+        last_path = paths[i] = g_strdup_printf("%s/%s", last_path, wnames[i]);
+        g_assert(!mkdir(paths[i], 0700));
+    }
+
+    fs_attach(v9p);
+    req = v9fs_twalk(v9p, 0, 1, P9_MAXWELEM, wnames);
+    v9fs_rwalk(req, &nwqid, &wqid);
+
+    g_assert_cmpint(nwqid, ==, P9_MAXWELEM);
+
+    for (i = 0; i < P9_MAXWELEM; i++) {
+        rmdir(paths[P9_MAXWELEM - i - 1]);
+        g_free(paths[P9_MAXWELEM - i - 1]);
+        g_free(wnames[i]);
+    }
+
+    g_free(wqid);
+}
+
+static void fs_walk_no_slash(QVirtIO9P *v9p)
+{
+    char *const wnames[] = { g_strdup(" /") };
+    P9Req *req;
+    uint32_t err;
+
+    fs_attach(v9p);
+    req = v9fs_twalk(v9p, 0, 1, 1, wnames);
+    v9fs_rlerror(req, &err);
+
+    g_assert_cmpint(err, ==, ENOENT);
+
+    g_free(wnames[0]);
+}
+
+static void fs_walk_dotdot(QVirtIO9P *v9p)
+{
+    char *const wnames[] = { g_strdup("..") };
+    v9fs_qid root_qid, *wqid;
+    P9Req *req;
+
+    fs_version(v9p);
+    req = v9fs_tattach(v9p, 0, getuid());
+    v9fs_rattach(req, &root_qid);
+
+    req = v9fs_twalk(v9p, 0, 1, 1, wnames);
+    v9fs_rwalk(req, NULL, &wqid); /* We now we'll get one qid */
+
+    g_assert_cmpmem(&root_qid, 13, wqid[0], 13);
+
+    g_free(wqid);
+    g_free(wnames[0]);
+}
+
+typedef void (*v9fs_test_fn)(QVirtIO9P *v9p);
+
+static void v9fs_run_pci_test(gconstpointer data)
+{
+    v9fs_test_fn fn = data;
+    QVirtIO9P *v9p = qvirtio_9p_pci_start();
+
+    if (fn) {
+        fn(v9p);
+    }
+    qvirtio_9p_pci_stop(v9p);
+}
+
+static void v9fs_qtest_pci_add(const char *path, v9fs_test_fn fn)
+{
+    qtest_add_data_func(path, fn, v9fs_run_pci_test);
 }
 
 int main(int argc, char **argv)
 {
     g_test_init(&argc, &argv, NULL);
-    qtest_add_func("/virtio/9p/pci/nop", pci_nop);
-    qtest_add_func("/virtio/9p/pci/basic/configuration", pci_basic_config);
+    v9fs_qtest_pci_add("/virtio/9p/pci/nop", NULL);
+    v9fs_qtest_pci_add("/virtio/9p/pci/config", pci_config);
+    v9fs_qtest_pci_add("/virtio/9p/pci/fs/version/basic", fs_version);
+    v9fs_qtest_pci_add("/virtio/9p/pci/fs/attach/basic", fs_attach);
+    v9fs_qtest_pci_add("/virtio/9p/pci/fs/walk/basic", fs_walk);
+    v9fs_qtest_pci_add("/virtio/9p/pci/fs/walk/no_slash", fs_walk_no_slash);
+    v9fs_qtest_pci_add("/virtio/9p/pci/fs/walk/dotdot_from_root",
+                       fs_walk_dotdot);
 
     return g_test_run();
 }