fs/9p: Add xattr callbacks for POSIX ACL

This patch implement fetching POSIX ACL from the server

Signed-off-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>

3 files changed, 47 insertions, 0 deletions

diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index a8c013615a22..4293b4599ff6 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -94,3 +94,44 @@ int v9fs_check_acl(struct inode *inode, int mask)
         }
         return -EAGAIN;
 }
+
+static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
+                              void *buffer, size_t size, int type)
+{
+        struct posix_acl *acl;
+        int error;
+
+        if (strcmp(name, "") != 0)
+                return -EINVAL;
+
+        acl = v9fs_get_cached_acl(dentry->d_inode, type);
+        if (IS_ERR(acl))
+                return PTR_ERR(acl);
+        if (acl == NULL)
+                return -ENODATA;
+        error = posix_acl_to_xattr(acl, buffer, size);
+        posix_acl_release(acl);
+
+        return error;
+}
+
+static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
+                              const void *value, size_t size,
+                              int flags, int type)
+{
+        return 0;
+}
+
+const struct xattr_handler v9fs_xattr_acl_access_handler = {
+        .prefix = POSIX_ACL_XATTR_ACCESS,
+        .flags  = ACL_TYPE_ACCESS,
+        .get    = v9fs_xattr_get_acl,
+        .set    = v9fs_xattr_set_acl,
+};
+
+const struct xattr_handler v9fs_xattr_acl_default_handler = {
+        .prefix = POSIX_ACL_XATTR_DEFAULT,
+        .flags  = ACL_TYPE_DEFAULT,
+        .get    = v9fs_xattr_get_acl,
+        .set    = v9fs_xattr_set_acl,
+};
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index 67ac6cfc1a07..43ec7df84336 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -164,5 +164,9 @@ ssize_t v9fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
 
 const struct xattr_handler *v9fs_xattr_handlers[] = {
         &v9fs_xattr_user_handler,
+#ifdef CONFIG_9P_FS_POSIX_ACL
+        &v9fs_xattr_acl_access_handler,
+        &v9fs_xattr_acl_default_handler,
+#endif
         NULL
 };
diff --git a/fs/9p/xattr.h b/fs/9p/xattr.h
index ec908c693342..eaa837c53bd5 100644
--- a/fs/9p/xattr.h
+++ b/fs/9p/xattr.h
@@ -20,6 +20,8 @@
 
 extern const struct xattr_handler *v9fs_xattr_handlers[];
 extern struct xattr_handler v9fs_xattr_user_handler;
+extern const struct xattr_handler v9fs_xattr_acl_access_handler;
+extern const struct xattr_handler v9fs_xattr_acl_default_handler;
 
 extern ssize_t v9fs_fid_xattr_get(struct p9_fid *, const char *,
                                   void *, size_t);