LU-11595 mdt: fix read-on-open for big PAGE_SIZE

[fs/lustre-release.git] / lustre / llite / file.c

diff --git a/lustre/llite/file.c b/lustre/llite/file.c
index 8007956..f866fba 100644 (file)
--- a/lustre/llite/file.c
+++ b/lustre/llite/file.c
@@ -443,8 +443,26 @@ void ll_dom_finish_open(struct inode *inode, struct ptlrpc_request *req,
        if (rnb == NULL || rnb->rnb_len == 0)
                RETURN_EXIT;
 
-       CDEBUG(D_INFO, "Get data buffer along with open, len %i, i_size %llu\n",
-              rnb->rnb_len, i_size_read(inode));
+       /* LU-11595: Server may return whole file and that is OK always or
+        * it may return just file tail and its offset must be aligned with
+        * client PAGE_SIZE to be used on that client, if server's PAGE_SIZE is
+        * smaller then offset may be not aligned and that data is just ignored.
+        */
+       if (rnb->rnb_offset % PAGE_SIZE)
+               RETURN_EXIT;
+
+       /* Server returns whole file or just file tail if it fills in
+        * reply buffer, in both cases total size should be inode size.
+        */
+       if (rnb->rnb_offset + rnb->rnb_len < i_size_read(inode)) {
+               CERROR("%s: server returns off/len %llu/%u < i_size %llu\n",
+                      ll_get_fsname(inode->i_sb, NULL, 0), rnb->rnb_offset,
+                      rnb->rnb_len, i_size_read(inode));
+               RETURN_EXIT;
+       }
+
+       CDEBUG(D_INFO, "Get data along with open at %llu len %i, i_size %llu\n",
+              rnb->rnb_offset, rnb->rnb_len, i_size_read(inode));
 
        data = (char *)rnb + sizeof(*rnb);