X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Frw.c;h=9b2ecdd78446e257ced06a56f3477b034fd6e9d0;hp=2979d17f9d21398bfba4c09f6b227ff81b0e653a;hb=6bce536725efd166d2772f13fe954f271f9c53b8;hpb=b9c155065d2ca4a6037a0ca4bfc788d6961fdc8e

diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c
index 2979d17..9b2ecdd 100644
--- a/lustre/llite/rw.c
+++ b/lustre/llite/rw.c
@@ -1569,6 +1569,20 @@ int ll_readpage(struct file *file, struct page *vmpage)
 		RETURN(result);
 	}
 
+	/**
+	 * Direct read can fall back to buffered read, but DIO is done
+	 * with lockless i/o, and buffered requires LDLM locking, so in
+	 * this case we must restart without lockless.
+	 */
+	if (file->f_flags & O_DIRECT &&
+	    lcc && lcc->lcc_type == LCC_RW &&
+	    !io->ci_ignore_lockless) {
+		unlock_page(vmpage);
+		io->ci_ignore_lockless = 1;
+		io->ci_need_restart = 1;
+		RETURN(-ENOLCK);
+	}
+
 	LASSERT(io->ci_state == CIS_IO_GOING);
 	page = cl_page_find(env, clob, vmpage->index, vmpage, CPT_CACHEABLE);
 	if (!IS_ERR(page)) {