9p: Implement TREADLINK operation for 9p2000.L
Synopsis
size[4] TReadlink tag[2] fid[4]
size[4] RReadlink tag[2] target[s]
Description
Readlink is used to return the contents of the symoblic link
referred by fid. Contents of symboic link is returned as a
response.
target[s] - Contents of the symbolic link referred by fid.
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 68f0297..8841907 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -1527,7 +1527,7 @@
if (IS_ERR(fid))
return PTR_ERR(fid);
- if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses))
+ if (!v9fs_proto_dotu(v9ses))
return -EBADF;
st = p9_client_stat(fid);
@@ -1995,6 +1995,60 @@
return err;
}
+static int
+v9fs_vfs_readlink_dotl(struct dentry *dentry, char *buffer, int buflen)
+{
+ int retval;
+ struct p9_fid *fid;
+ char *target = NULL;
+
+ P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
+ retval = -EPERM;
+ fid = v9fs_fid_lookup(dentry);
+ if (IS_ERR(fid))
+ return PTR_ERR(fid);
+
+ retval = p9_client_readlink(fid, &target);
+ if (retval < 0)
+ return retval;
+
+ strncpy(buffer, target, buflen);
+ P9_DPRINTK(P9_DEBUG_VFS, "%s -> %s\n", dentry->d_name.name, buffer);
+
+ retval = strnlen(buffer, buflen);
+ return retval;
+}
+
+/**
+ * v9fs_vfs_follow_link_dotl - follow a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ *
+ */
+
+static void *
+v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
+{
+ int len = 0;
+ char *link = __getname();
+
+ P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
+
+ if (!link)
+ link = ERR_PTR(-ENOMEM);
+ else {
+ len = v9fs_vfs_readlink_dotl(dentry, link, PATH_MAX);
+ if (len < 0) {
+ __putname(link);
+ link = ERR_PTR(len);
+ } else
+ link[min(len, PATH_MAX-1)] = 0;
+ }
+ nd_set_link(nd, link);
+
+ return NULL;
+}
+
static const struct inode_operations v9fs_dir_inode_operations_dotu = {
.create = v9fs_vfs_create,
.lookup = v9fs_vfs_lookup,
@@ -2064,8 +2118,8 @@
};
static const struct inode_operations v9fs_symlink_inode_operations_dotl = {
- .readlink = generic_readlink,
- .follow_link = v9fs_vfs_follow_link,
+ .readlink = v9fs_vfs_readlink_dotl,
+ .follow_link = v9fs_vfs_follow_link_dotl,
.put_link = v9fs_vfs_put_link,
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr_dotl,