ceph: always get rstat from auth mds

rstat is not tracked by capability. client can't know if rstat from
non-auth mds is uptodate or not.

Link: http://tracker.ceph.com/issues/23538
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/caps.c

@@ -69,6 +69,8 @@ static char *gcap_string(char *s, int c)
 		*s++ = 'w';
 	if (c & CEPH_CAP_GBUFFER)
 		*s++ = 'b';
+	if (c & CEPH_CAP_GWREXTEND)
+		*s++ = 'a';
 	if (c & CEPH_CAP_GLAZYIO)
 		*s++ = 'l';
 	return s;

fs/ceph/inode.c

@@ -854,6 +854,18 @@ static int fill_inode(struct inode *inode, struct page *locked_page,
 		}
 	}
 
+	/* layout and rstat are not tracked by capability, update them if
+	 * the inode info is from auth mds */
+	if (new_version || (info->cap.flags & CEPH_CAP_FLAG_AUTH)) {
+		if (S_ISDIR(inode->i_mode)) {
+			ci->i_dir_layout = iinfo->dir_layout;
+			ci->i_rbytes = le64_to_cpu(info->rbytes);
+			ci->i_rfiles = le64_to_cpu(info->rfiles);
+			ci->i_rsubdirs = le64_to_cpu(info->rsubdirs);
+			ceph_decode_timespec(&ci->i_rctime, &info->rctime);
+		}
+	}
+
 	/* xattrs */
 	/* note that if i_xattrs.len <= 4, i_xattrs.data will still be NULL. */
 	if ((ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))  &&
@@ -919,14 +931,9 @@ static int fill_inode(struct inode *inode, struct page *locked_page,
 		inode->i_op = &ceph_dir_iops;
 		inode->i_fop = &ceph_dir_fops;
 
-		ci->i_dir_layout = iinfo->dir_layout;
 
 		ci->i_files = le64_to_cpu(info->files);
 		ci->i_subdirs = le64_to_cpu(info->subdirs);
-		ci->i_rbytes = le64_to_cpu(info->rbytes);
-		ci->i_rfiles = le64_to_cpu(info->rfiles);
-		ci->i_rsubdirs = le64_to_cpu(info->rsubdirs);
-		ceph_decode_timespec(&ci->i_rctime, &info->rctime);
 		break;
 	default:
 		pr_err("fill_inode %llx.%llx BAD mode 0%o\n",
@@ -2178,6 +2185,7 @@ int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
 	struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
 	struct ceph_mds_client *mdsc = fsc->mdsc;
 	struct ceph_mds_request *req;
+	int mode;
 	int err;
 
 	if (ceph_snap(inode) == CEPH_SNAPDIR) {
@@ -2190,7 +2198,8 @@ int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
 	if (!force && ceph_caps_issued_mask(ceph_inode(inode), mask, 1))
 		return 0;
 
-	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
+	mode = (mask & CEPH_STAT_RSTAT) ? USE_AUTH_MDS : USE_ANY_MDS;
+	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, mode);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 	req->r_inode = inode;

fs/ceph/xattr.c

@@ -56,6 +56,7 @@ struct ceph_vxattr {
 
 #define VXATTR_FLAG_READONLY		(1<<0)
 #define VXATTR_FLAG_HIDDEN		(1<<1)
+#define VXATTR_FLAG_RSTAT		(1<<2)
 
 /* layouts */
 
@@ -265,14 +266,16 @@ static size_t ceph_vxattrcb_quota_max_files(struct ceph_inode_info *ci,
 #define CEPH_XATTR_NAME2(_type, _name, _name2)	\
 	XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
 
-#define XATTR_NAME_CEPH(_type, _name)					\
+#define XATTR_NAME_CEPH(_type, _name, _flags)				\
 	{								\
 		.name = CEPH_XATTR_NAME(_type, _name),			\
 		.name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
 		.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
-		.exists_cb = NULL,				\
-		.flags = VXATTR_FLAG_READONLY,			\
+		.exists_cb = NULL,					\
+		.flags = (VXATTR_FLAG_READONLY | _flags),		\
 	}
+#define XATTR_RSTAT_FIELD(_type, _name)			\
+	XATTR_NAME_CEPH(_type, _name, VXATTR_FLAG_RSTAT)
 #define XATTR_LAYOUT_FIELD(_type, _name, _field)			\
 	{								\
 		.name = CEPH_XATTR_NAME2(_type, _name, _field),	\
@@ -303,14 +306,14 @@ static struct ceph_vxattr ceph_dir_vxattrs[] = {
 	XATTR_LAYOUT_FIELD(dir, layout, object_size),
 	XATTR_LAYOUT_FIELD(dir, layout, pool),
 	XATTR_LAYOUT_FIELD(dir, layout, pool_namespace),
-	XATTR_NAME_CEPH(dir, entries),
-	XATTR_NAME_CEPH(dir, files),
-	XATTR_NAME_CEPH(dir, subdirs),
-	XATTR_NAME_CEPH(dir, rentries),
-	XATTR_NAME_CEPH(dir, rfiles),
-	XATTR_NAME_CEPH(dir, rsubdirs),
-	XATTR_NAME_CEPH(dir, rbytes),
-	XATTR_NAME_CEPH(dir, rctime),
+	XATTR_NAME_CEPH(dir, entries, 0),
+	XATTR_NAME_CEPH(dir, files, 0),
+	XATTR_NAME_CEPH(dir, subdirs, 0),
+	XATTR_RSTAT_FIELD(dir, rentries),
+	XATTR_RSTAT_FIELD(dir, rfiles),
+	XATTR_RSTAT_FIELD(dir, rsubdirs),
+	XATTR_RSTAT_FIELD(dir, rbytes),
+	XATTR_RSTAT_FIELD(dir, rctime),
 	{
 		.name = "ceph.quota",
 		.name_size = sizeof("ceph.quota"),
@@ -807,7 +810,10 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 	/* let's see if a virtual xattr was requested */
 	vxattr = ceph_match_vxattr(inode, name);
 	if (vxattr) {
-		err = ceph_do_getattr(inode, 0, true);
+		int mask = 0;
+		if (vxattr->flags & VXATTR_FLAG_RSTAT)
+			mask |= CEPH_STAT_RSTAT;
+		err = ceph_do_getattr(inode, mask, true);
 		if (err)
 			return err;
 		err = -ENODATA;

include/linux/ceph/ceph_fs.h

@@ -628,6 +628,7 @@ int ceph_flags_to_mode(int flags);
 				 CEPH_CAP_XATTR_SHARED)
 #define CEPH_STAT_CAP_INLINE_DATA (CEPH_CAP_FILE_SHARED | \
 				   CEPH_CAP_FILE_RD)
+#define CEPH_STAT_RSTAT CEPH_CAP_FILE_WREXTEND
 
 #define CEPH_CAP_ANY_SHARED (CEPH_CAP_AUTH_SHARED |			\
 			      CEPH_CAP_LINK_SHARED |			\