Add way to query creation time of file via cifs xattr
Add parsing for new pseudo-xattr user.cifs.creationtime file
attribute to allow backup and test applications to view
birth time of file on cifs/smb3 mounts.
Signed-off-by: Steve French <steve.french@primarydata.com>
diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c
index c4237b8..20af518 100644
--- a/fs/cifs/xattr.c
+++ b/fs/cifs/xattr.c
@@ -34,7 +34,7 @@
#define MAX_EA_VALUE_SIZE 65535
#define CIFS_XATTR_CIFS_ACL "system.cifs_acl"
#define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */
-
+#define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */
/* BB need to add server (Samba e.g) support for security and trusted prefix */
enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT };
@@ -169,6 +169,29 @@
return sizeof(__u32);
}
+static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
+ void *value, size_t size)
+{
+ ssize_t rc;
+ __u64 * pcreatetime;
+
+ rc = cifs_revalidate_dentry_attr(dentry);
+ if (rc)
+ return rc;
+
+ if ((value == NULL) || (size == 0))
+ return sizeof(__u64);
+ else if (size < sizeof(__u64))
+ return -ERANGE;
+
+ /* return dos attributes as pseudo xattr */
+ pcreatetime = (__u64 *)value;
+ *pcreatetime = CIFS_I(inode)->createtime;
+ return sizeof(__u64);
+
+ return rc;
+}
+
static int cifs_xattr_get(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
@@ -202,6 +225,9 @@
if (strcmp(name, CIFS_XATTR_ATTRIB) == 0) {
rc = cifs_attrib_get(dentry, inode, value, size);
break;
+ } else if (strcmp(name, CIFS_XATTR_CREATETIME) == 0) {
+ rc = cifs_creation_time_get(dentry, inode, value, size);
+ break;
}
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)