[Qemu-devel] [PATCH] qemu: virtio-9p: Implement TMKNOD

[M. Mohan Kumar]

Implement TMKNOD as part of 2000.L Work

Synopsis

    size[4] Tmknod tag[2] fid[4] name[s] mode[4] dev[4] gid[4]

    size[4] Rmknod tag[2] qid[13]

Description

    mknod asks the file server to create a device node with given device
    type, mode and gid. The qid for the new device node is returned with
    the mknod reply message.

Note:
Existing v9fs_do_mknod function is changed to accomodate the dotl mknod
version.

Signed-off-by: M. Mohan Kumar <address@hidden>
---
 hw/virtio-9p.c |   76 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
 hw/virtio-9p.h |   13 +++++++++
 2 files changed, 82 insertions(+), 7 deletions(-)

diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c
index c217fa5..9307cc3 100644
--- a/hw/virtio-9p.c
+++ b/hw/virtio-9p.c
@@ -161,15 +161,16 @@ static int v9fs_do_chmod(V9fsState *s, V9fsString *path, 
mode_t mode)
     return s->ops->chmod(&s->ctx, path->data, &cred);
 }
 
-static int v9fs_do_mknod(V9fsState *s, V9fsCreateState *vs, mode_t mode,
-        dev_t dev)
+static int v9fs_do_mknod(V9fsState *s, char *name,
+        mode_t mode, dev_t dev, uid_t uid, gid_t gid)
 {
     FsCred cred;
     cred_init(&cred);
-    cred.fc_uid = vs->fidp->uid;
+    cred.fc_uid = uid;
+    cred.fc_gid = gid;
     cred.fc_mode = mode;
     cred.fc_rdev = dev;
-    return s->ops->mknod(&s->ctx, vs->fullname.data, &cred);
+    return s->ops->mknod(&s->ctx, name, &cred);
 }
 
 static int v9fs_do_mkdir(V9fsState *s, V9fsCreateState *vs)
@@ -2043,13 +2044,16 @@ static void v9fs_create_post_lstat(V9fsState *s, 
V9fsCreateState *vs, int err)
         }
 
         nmode |= vs->perm & 0777;
-        err = v9fs_do_mknod(s, vs, nmode, makedev(major, minor));
+        err = v9fs_do_mknod(s, vs->fullname.data, nmode,
+                makedev(major, minor), vs->fidp->uid, -1);
         v9fs_create_post_perms(s, vs, err);
     } else if (vs->perm & P9_STAT_MODE_NAMED_PIPE) {
-        err = v9fs_do_mknod(s, vs, S_IFIFO | (vs->perm & 0777), 0);
+        err = v9fs_do_mknod(s, vs->fullname.data, S_IFIFO | (vs->perm & 0777),
+                0, vs->fidp->uid, -1);
         v9fs_post_create(s, vs, err);
     } else if (vs->perm & P9_STAT_MODE_SOCKET) {
-        err = v9fs_do_mknod(s, vs, S_IFSOCK | (vs->perm & 0777), 0);
+        err = v9fs_do_mknod(s, vs->fullname.data, S_IFSOCK | (vs->perm & 0777),
+                0, vs->fidp->uid, -1);
         v9fs_post_create(s, vs, err);
     } else {
         vs->fidp->fd = v9fs_do_open2(s, vs);
@@ -2461,12 +2465,70 @@ out:
     qemu_free(vs);
 }
 
+static void v9fs_mknod_post_mknod(V9fsState *s, V9fsMknodState *vs, int err)
+{
+    if (err == -1) {
+        err = -errno;
+        goto out;
+    }
+
+    err = v9fs_do_lstat(s, &vs->fullname, &vs->stbuf);
+    if (err == -1) {
+       err = -errno;
+       goto out;
+    }
+    stat_to_qid(&vs->stbuf, &vs->qid);
+    vs->offset += pdu_marshal(vs->pdu, vs->offset, "Q", &vs->qid);
+    err = vs->offset;
+out:
+    complete_pdu(s, vs->pdu, err);
+    v9fs_string_free(&vs->fullname);
+    v9fs_string_free(&vs->name);
+    qemu_free(vs);
+}
+
+static void v9fs_mknod(V9fsState *s, V9fsPDU *pdu)
+{
+    int32_t fid;
+    V9fsMknodState *vs;
+    ssize_t err = 0;
+    V9fsFidState *fidp;
+    gid_t gid;
+
+    vs = qemu_malloc(sizeof(*vs));
+    vs->pdu = pdu;
+    vs->offset = 7;
+
+    v9fs_string_init(&vs->fullname);
+    pdu_unmarshal(vs->pdu, vs->offset, "dsddd", &fid, &vs->name, &vs->mode,
+        &vs->rdev, &gid);
+
+    fidp = lookup_fid(s, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out;
+    }
+
+    v9fs_string_sprintf(&vs->fullname, "%s/%s", fidp->path.data, 
vs->name.data);
+    err = v9fs_do_mknod(s, vs->fullname.data, vs->mode, vs->rdev,
+        fidp->uid, gid);
+    v9fs_mknod_post_mknod(s, vs, err);
+    return;
+
+out:
+    complete_pdu(s, vs->pdu, err);
+    v9fs_string_free(&vs->fullname);
+    v9fs_string_free(&vs->name);
+    qemu_free(vs);
+}
+
 typedef void (pdu_handler_t)(V9fsState *s, V9fsPDU *pdu);
 
 static pdu_handler_t *pdu_handlers[] = {
     [P9_TREADDIR] = v9fs_readdir,
     [P9_TSTATFS] = v9fs_statfs,
     [P9_TGETATTR] = v9fs_getattr,
+    [P9_TMKNOD] = v9fs_mknod,
     [P9_TVERSION] = v9fs_version,
     [P9_TATTACH] = v9fs_attach,
     [P9_TSTAT] = v9fs_stat,
diff --git a/hw/virtio-9p.h b/hw/virtio-9p.h
index cb0b0ed..9c4ab1d 100644
--- a/hw/virtio-9p.h
+++ b/hw/virtio-9p.h
@@ -15,6 +15,8 @@
 enum {
     P9_TSTATFS = 8,
     P9_RSTATFS,
+    P9_TMKNOD = 18,
+    P9_RMKNOD,
     P9_TGETATTR = 24,
     P9_RGETATTR,
     P9_TREADDIR = 40,
@@ -310,6 +312,17 @@ typedef struct V9fsStatStateDotl {
     struct stat stbuf;
 } V9fsStatStateDotl;
 
+typedef struct V9fsMknodState {
+    V9fsPDU *pdu;
+    size_t offset;
+    V9fsQID qid;
+    int mode;
+    dev_t rdev;
+    struct stat stbuf;
+    V9fsString name;
+    V9fsString fullname;
+} V9fsMknodState;
+
 extern size_t pdu_packunpack(void *addr, struct iovec *sg, int sg_count,
                             size_t offset, size_t size, int pack);
 
-- 
1.6.6.1