diff mbox series

[v2,13/25] DAX: virtiofsd: Wire up passthrough_ll's lo_setupmapping

Message ID 20210414155137.46522-14-dgilbert@redhat.com (mailing list archive)
State New, archived
Headers show
Series virtiofs dax patches | expand

Commit Message

Dr. David Alan Gilbert April 14, 2021, 3:51 p.m. UTC
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Wire up passthrough_ll's setupmapping to allocate, send to virtio
and then reply OK.

Guest might not pass file pointer. In that case using inode info, open
the file again, mmap() and close fd.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
With fix from:
Signed-off-by: Fotis Xenakis <foxen@windowslive.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tools/virtiofsd/fuse_lowlevel.c  | 13 ++++++--
 tools/virtiofsd/passthrough_ll.c | 57 ++++++++++++++++++++++++++++++--
 2 files changed, 66 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 1a00307879..81c4c2b373 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -1899,8 +1899,17 @@  static void do_setupmapping(fuse_req_t req, fuse_ino_t nodeid,
     }
 
     if (req->se->op.setupmapping) {
-        req->se->op.setupmapping(req, nodeid, arg->foffset, arg->len,
-                                 arg->moffset, genflags, &fi);
+        /*
+         * TODO: Add a flag to request which tells if arg->fh is
+         * valid or not.
+         */
+        if (fi.fh == (uint64_t)-1) {
+            req->se->op.setupmapping(req, nodeid, arg->foffset, arg->len,
+                                     arg->moffset, genflags, NULL);
+        } else {
+            req->se->op.setupmapping(req, nodeid, arg->foffset, arg->len,
+                                     arg->moffset, genflags, &fi);
+        }
     } else {
         fuse_reply_err(req, ENOSYS);
     }
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index afa86650c1..bf7a7f3c23 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -3148,8 +3148,61 @@  static void lo_setupmapping(fuse_req_t req, fuse_ino_t ino, uint64_t foffset,
                             uint64_t len, uint64_t moffset, uint64_t flags,
                             struct fuse_file_info *fi)
 {
-    /* TODO */
-    fuse_reply_err(req, ENOSYS);
+    struct lo_data *lo = lo_data(req);
+    int ret = 0, fd;
+    VhostUserFSSlaveMsg *msg = g_malloc0(sizeof(VhostUserFSSlaveMsg) +
+                                         sizeof(VhostUserFSSlaveMsgEntry));
+    uint64_t vhu_flags;
+    char *buf;
+    bool writable = flags & O_RDWR;
+
+    fuse_log(FUSE_LOG_DEBUG,
+             "lo_setupmapping(ino=%" PRIu64 ", fi=0x%p,"
+             " foffset=%" PRIu64 ", len=%" PRIu64 ", moffset=%" PRIu64
+             ", flags=%" PRIu64 ")\n",
+             ino, (void *)fi, foffset, len, moffset, flags);
+
+    vhu_flags = VHOST_USER_FS_FLAG_MAP_R;
+    if (writable) {
+        vhu_flags |= VHOST_USER_FS_FLAG_MAP_W;
+    }
+
+    msg->count = 1;
+    msg->entries[0].fd_offset = foffset;
+    msg->entries[0].len = len;
+    msg->entries[0].c_offset = moffset;
+    msg->entries[0].flags = vhu_flags;
+
+    if (fi) {
+        fd = lo_fi_fd(req, fi);
+    } else {
+        ret = asprintf(&buf, "%i", lo_fd(req, ino));
+        if (ret == -1) {
+            g_free(msg);
+            return (void)fuse_reply_err(req, errno);
+        }
+
+        fd = openat(lo->proc_self_fd, buf, flags);
+        free(buf);
+        if (fd == -1) {
+            g_free(msg);
+            return (void)fuse_reply_err(req, errno);
+        }
+    }
+
+    ret = fuse_virtio_map(req, msg, fd);
+    if (ret < 0) {
+        fuse_log(FUSE_LOG_ERR,
+                 "%s: map over virtio failed (ino=%" PRId64
+                 "fd=%d moffset=0x%" PRIx64 "). err = %d\n",
+                 __func__, ino, fd, moffset, ret);
+    }
+
+    if (!fi) {
+        close(fd);
+    }
+    fuse_reply_err(req, -ret);
+    g_free(msg);
 }
 
 static void lo_removemapping(fuse_req_t req, struct fuse_session *se,