X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Finclude%2Flustre_mdc.h;h=27441f9e2839173272b93af6d26355d2286ef63e;hb=2a42554850e92ef1aa515269e7d2a4020403c12d;hp=f095a71ab67db602055d6555c0640b4204077c61;hpb=f95393b0d0a59cf3dc2f29cffc35dcc4cc9d7728;p=fs%2Flustre-release.git

diff --git a/lustre/include/lustre_mdc.h b/lustre/include/lustre_mdc.h
index f095a71..27441f9 100644
--- a/lustre/include/lustre_mdc.h
+++ b/lustre/include/lustre_mdc.h
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -30,6 +28,9 @@
  * Use is subject to license terms.
  */
 /*
+ * Copyright (c) 2012 Whamcloud, Inc.
+ */
+/*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
@@ -51,23 +52,16 @@
 # include <linux/fs.h>
 # include <linux/dcache.h>
 # ifdef CONFIG_FS_POSIX_ACL
-#  ifdef HAVE_XATTR_ACL
-#   include <linux/xattr_acl.h>
-#  endif /*HAVE_XATTR_ACL */
-#  ifdef HAVE_LINUX_POSIX_ACL_XATTR_H
-#   include <linux/posix_acl_xattr.h>
-#  endif /* HAVE_LINUX_POSIX_ACL_XATTR_H */
+#  include <linux/posix_acl_xattr.h>
 # endif /* CONFIG_FS_POSIX_ACL */
-# ifndef HAVE_VFS_INTENT_PATCHES
 # include <linux/lustre_intent.h>
-# endif /* HAVE_VFS_INTENT_PATCHES */
 #endif /* __KERNEL__ */
 #include <lustre_handles.h>
 #include <libcfs/libcfs.h>
+#include <obd_class.h>
 #include <lustre/lustre_idl.h>
 #include <lustre_lib.h>
 #include <lustre_dlm.h>
-#include <lustre_log.h>
 #include <lustre_export.h>
 
 struct ptlrpc_client;
@@ -76,36 +70,81 @@ struct ptlrpc_request;
 struct obd_device;
 
 struct mdc_rpc_lock {
-        cfs_semaphore_t  rpcl_sem;
-        struct lookup_intent *rpcl_it;
+	struct mutex		rpcl_mutex;
+	struct lookup_intent	*rpcl_it;
+	int			rpcl_fakes;
 };
 
+#define MDC_FAKE_RPCL_IT ((void *)0x2c0012bfUL)
+
 static inline void mdc_init_rpc_lock(struct mdc_rpc_lock *lck)
 {
-        cfs_sema_init(&lck->rpcl_sem, 1);
+	mutex_init(&lck->rpcl_mutex);
         lck->rpcl_it = NULL;
 }
 
 static inline void mdc_get_rpc_lock(struct mdc_rpc_lock *lck,
-                                    struct lookup_intent *it)
+				    struct lookup_intent *it)
 {
-        ENTRY;
-        if (!it || (it->it_op != IT_GETATTR && it->it_op != IT_LOOKUP)) {
-                cfs_down(&lck->rpcl_sem);
-                LASSERT(lck->rpcl_it == NULL);
-                lck->rpcl_it = it;
-        }
+	ENTRY;
+
+	if (it != NULL && (it->it_op == IT_GETATTR || it->it_op == IT_LOOKUP))
+		return;
+
+	/* This would normally block until the existing request finishes.
+	 * If fail_loc is set it will block until the regular request is
+	 * done, then set rpcl_it to MDC_FAKE_RPCL_IT.  Once that is set
+	 * it will only be cleared when all fake requests are finished.
+	 * Only when all fake requests are finished can normal requests
+	 * be sent, to ensure they are recoverable again. */
+ again:
+	mutex_lock(&lck->rpcl_mutex);
+
+	if (CFS_FAIL_CHECK_QUIET(OBD_FAIL_MDC_RPCS_SEM)) {
+		lck->rpcl_it = MDC_FAKE_RPCL_IT;
+		lck->rpcl_fakes++;
+		mutex_unlock(&lck->rpcl_mutex);
+		return;
+	}
+
+	/* This will only happen when the CFS_FAIL_CHECK() was
+	 * just turned off but there are still requests in progress.
+	 * Wait until they finish.  It doesn't need to be efficient
+	 * in this extremely rare case, just have low overhead in
+	 * the common case when it isn't true. */
+	while (unlikely(lck->rpcl_it == MDC_FAKE_RPCL_IT)) {
+		mutex_unlock(&lck->rpcl_mutex);
+		cfs_schedule_timeout(cfs_time_seconds(1) / 4);
+		goto again;
+	}
+
+	LASSERT(lck->rpcl_it == NULL);
+	lck->rpcl_it = it;
 }
 
 static inline void mdc_put_rpc_lock(struct mdc_rpc_lock *lck,
-                                    struct lookup_intent *it)
+				    struct lookup_intent *it)
 {
-        if (!it || (it->it_op != IT_GETATTR && it->it_op != IT_LOOKUP)) {
-                LASSERT(it == lck->rpcl_it);
-                lck->rpcl_it = NULL;
-                cfs_up(&lck->rpcl_sem);
-        }
-        EXIT;
+	if (it != NULL && (it->it_op == IT_GETATTR || it->it_op == IT_LOOKUP))
+		goto out;
+
+	if (lck->rpcl_it == MDC_FAKE_RPCL_IT) { /* OBD_FAIL_MDC_RPCS_SEM */
+		mutex_lock(&lck->rpcl_mutex);
+
+		LASSERTF(lck->rpcl_fakes > 0, "%d\n", lck->rpcl_fakes);
+		lck->rpcl_fakes--;
+
+		if (lck->rpcl_fakes == 0)
+			lck->rpcl_it = NULL;
+
+	} else {
+		LASSERTF(it == lck->rpcl_it, "%p != %p\n", it, lck->rpcl_it);
+		lck->rpcl_it = NULL;
+	}
+
+	mutex_unlock(&lck->rpcl_mutex);
+ out:
+	EXIT;
 }
 
 static inline void mdc_update_max_ea_from_body(struct obd_export *exp,