[svn-r7460] Purpose:

    Update

Description:
    Added extra parameter to the H5AC_protect() function that indicates
    if the cache being asked for is going to be written to or just read
    from. Those AC_protect calls that were H5AC_find calls are now
    read-only. The rest are writes.

Platforms tested:
    Linux (h5committest not needed due to size and small impact)

Misc. update:

11 files changed, 87 insertions, 61 deletions

diff --git a/src/H5AC.c b/src/H5AC.c
index f8890d8..6aff83b 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -1408,11 +1408,15 @@ done:
  * Modifications:
  *		Robb Matzke, 1999-07-27
  *		The ADDR argument is passed by value.
+ *
+ *              Bill Wendling, 2003-09-10
+ *              Added parameter to indicate whether this is a READ or
+ *              WRITE type of protect.
  *-------------------------------------------------------------------------
  */
 void *
 H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
-	     const void *udata1, void *udata2)
+	     const void *udata1, void *udata2, H5AC_protect_t rw)
 {
     unsigned                idx;                /* Index in cache */
     void                   *thing=NULL;
@@ -1586,6 +1590,8 @@ H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
 
     cache->nprots += 1;
 
+    rw = rw;    /* Remove compiler warning if no FPHDF5 used */
+
     /* Set return value */
     ret_value=thing;
 
diff --git a/src/H5ACprivate.h b/src/H5ACprivate.h
index 79fd4e8..f05a32c 100644
--- a/src/H5ACprivate.h
+++ b/src/H5ACprivate.h
@@ -87,6 +87,19 @@ typedef struct H5AC_class_t {
     H5AC_clear_func_t   clear;
 } H5AC_class_t;
 
+/*===----------------------------------------------------------------------===
+ *                             Protect Types
+ *===----------------------------------------------------------------------===
+ *
+ * These are for the wrapper functions to H5AC_protect. They specify what
+ * type of operation you're planning on doing to the metadata. The
+ * Flexible Parallel HDF5 locking can then act accordingly.
+ */
+typedef enum H5AC_protect_t {
+    H5AC_WRITE,                 /* Protect object for writing                */
+    H5AC_READ                   /* Protect object for reading                */
+} H5AC_protect_t;
+
 /*
  * A cache has a certain number of entries.  Objects are mapped into a
  * cache entry by hashing the object's file address.  Each file has its
@@ -135,10 +148,11 @@ H5_DLL herr_t H5AC_init(void);
 H5_DLL herr_t H5AC_create(const H5F_t *f, int size_hint);
 H5_DLL herr_t H5AC_set(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
 			void *thing);
-H5_DLL void *H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
-			   const void *udata1, void *udata2);
+H5_DLL void *H5AC_protect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type,
+                          haddr_t addr, const void *udata1, void *udata2,
+                          H5AC_protect_t rw);
 H5_DLL herr_t H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
-			      void *thing, hbool_t deleted);
+			     void *thing, hbool_t deleted);
 H5_DLL herr_t H5AC_flush(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
 			  unsigned flags);
 H5_DLL herr_t H5AC_rename(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type,
diff --git a/src/H5B.c b/src/H5B.c
index 87575f1..5977e00 100644
--- a/src/H5B.c
+++ b/src/H5B.c
@@ -637,7 +637,7 @@ H5B_find(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void *u
      * Perform a binary search to locate the child which contains
      * the thing for which we're searching.
      */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree node")
     rt = bt->nchildren;
 
@@ -781,7 +781,7 @@ H5B_split(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, H5B_t *old_bt, haddr
      */
     if (H5B_create(f, dxpl_id, type, udata, new_addr_p/*out*/) < 0)
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTINIT, FAIL, "unable to create B-tree")
-    if (NULL==(new_bt=H5AC_protect(f, dxpl_id, H5AC_BT, *new_addr_p, type, udata)))
+    if (NULL==(new_bt=H5AC_protect(f, dxpl_id, H5AC_BT, *new_addr_p, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to protect B-tree")
     new_bt->level = old_bt->level;
 
@@ -821,7 +821,7 @@ H5B_split(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, H5B_t *old_bt, haddr
     new_bt->right = old_bt->right;
 
     if (H5F_addr_defined(old_bt->right)) {
-	if (NULL == (tmp_bt = H5AC_protect(f, dxpl_id, H5AC_BT, old_bt->right, type, udata)))
+	if (NULL == (tmp_bt = H5AC_protect(f, dxpl_id, H5AC_BT, old_bt->right, type, udata, H5AC_WRITE)))
 	    HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load right sibling")
 
 	tmp_bt->cache_info.dirty = TRUE;
@@ -979,7 +979,7 @@ H5B_insert(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr,
     assert(H5B_INS_RIGHT == my_ins);
 
     /* the current root */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_READ)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to locate root of B-tree")
 
     level = bt->level;
@@ -1006,7 +1006,7 @@ H5B_insert(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr,
     bt = NULL;
     
     /* the new node */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, child, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, child, type, udata, H5AC_READ)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load new node")
 
     if (!rt_key_changed) {
@@ -1039,7 +1039,7 @@ H5B_insert(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr,
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "unable to allocate file space to move root")
 
     /* update the new child's left pointer */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, child, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, child, type, udata, H5AC_WRITE)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load new child")
 
     bt->cache_info.dirty = TRUE;
@@ -1055,7 +1055,7 @@ H5B_insert(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr,
      * at the new location -QAK
      */
     /* Bring the old root into the cache if it's not already */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
         HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load new child")
 
     /* Make certain the old root info is marked as dirty before moving it, */
@@ -1301,7 +1301,7 @@ H5B_insert_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type
      * data.  When the search completes IDX points to the child that
      * should get the new data.
      */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, H5B_INS_ERROR, "unable to load node")
     rt = bt->nchildren;
 
@@ -1493,7 +1493,7 @@ H5B_insert_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type
 	if (bt->nchildren == 2 * H5F_KVALUE(f, type)) {
 	    if (H5B_split(f, dxpl_id, type, bt, addr, idx, split_ratios, udata, new_node_p/*out*/)<0)
 		HGOTO_ERROR(H5E_BTREE, H5E_CANTSPLIT, H5B_INS_ERROR, "unable to split node")
-	    if (NULL == (twin = H5AC_protect(f, dxpl_id, H5AC_BT, *new_node_p, type, udata)))
+	    if (NULL == (twin = H5AC_protect(f, dxpl_id, H5AC_BT, *new_node_p, type, udata, H5AC_WRITE)))
 		HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, H5B_INS_ERROR, "unable to load node")
 	    if (idx<bt->nchildren) {
 		tmp_bt = bt;
@@ -1596,7 +1596,7 @@ H5B_iterate (H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, H5B_operator_t op
     assert(H5F_addr_defined(addr));
     assert(udata);
 
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_READ)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree node")
 
     level = bt->level;
@@ -1626,7 +1626,7 @@ H5B_iterate (H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, H5B_operator_t op
 	     * leave the B-tree node protected during an application
 	     * callback.
 	     */
-	    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, cur_addr, type, udata)))
+	    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, cur_addr, type, udata, H5AC_READ)))
 		HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "B-tree node")
 
 	    for (u=0; u<bt->nchildren; u++)
@@ -1733,7 +1733,7 @@ H5B_remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type
      * Perform a binary search to locate the child which contains the thing
      * for which we're searching.
      */
-    if (NULL==(bt=H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL==(bt=H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, H5B_INS_ERROR, "unable to load B-tree node")
     rt = bt->nchildren;
     while (lt<rt && cmp) {
@@ -1828,7 +1828,7 @@ H5B_remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type
 	bt->ndirty = 0;
 	if (level>0) {
 	    if (H5F_addr_defined(bt->left)) {
-		if (NULL == (sibling = H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, type, udata)))
+		if (NULL == (sibling = H5AC_protect(f, dxpl_id, H5AC_BT, bt->left, type, udata, H5AC_WRITE)))
 		    HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, H5B_INS_ERROR, "unable to load node from tree")
 
 		sibling->right = bt->right;
@@ -1840,7 +1840,7 @@ H5B_remove_helper(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type
                 sibling=NULL;   /* Make certain future references will be caught */
 	    }
 	    if (H5F_addr_defined(bt->right)) {
-		if (NULL == (sibling = H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, type, udata)))
+		if (NULL == (sibling = H5AC_protect(f, dxpl_id, H5AC_BT, bt->right, type, udata, H5AC_WRITE)))
 		    HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, H5B_INS_ERROR, "unable to unlink node from tree")
 
 		sibling->left = bt->left;
@@ -2002,7 +2002,7 @@ H5B_remove(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void
      * If the B-tree is now empty then make sure we mark the root node as
      * being at level zero
      */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree root node")
 
     if (0==bt->nchildren && 0!=bt->level) {
@@ -2055,7 +2055,7 @@ H5B_delete(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void
     assert(H5F_addr_defined(addr));
 
     /* Lock this B-tree node into memory for now */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree node")
 
     /* Iterate over all children in tree, deleting them */
@@ -2097,6 +2097,9 @@ H5B_delete(H5F_t *f, hid_t dxpl_id, const H5B_class_t *type, haddr_t addr, void
     bt=NULL;    /* Make certain future references will be caught */
 
 done:
+    if (bt && H5AC_unprotect(f, dxpl_id, H5AC_BT, addr, bt, FALSE)<0)
+        HGOTO_ERROR(H5E_BTREE, H5E_PROTECT, FAIL, "unable to release B-tree node in cache")
+
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5B_delete() */
 
@@ -2288,7 +2291,7 @@ H5B_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int f
     /*
      * Load the tree node.
      */
-    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata)))
+    if (NULL == (bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_READ)))
 	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load B-tree node")
 
     /*
@@ -2408,7 +2411,7 @@ H5B_assert(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type, void
 	}
     }
     /* Initialize the queue */
-    bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata);
+    bt = H5AC_protect(f, dxpl_id, H5AC_BT, addr, type, udata, H5AC_READ);
     assert(bt);
     cur = H5MM_calloc(sizeof(struct child_t));
     assert (cur);
@@ -2427,7 +2430,7 @@ H5B_assert(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5B_class_t *type, void
      * test.
      */
     for (ncell = 0; cur; ncell++) {
-	bt = H5AC_protect(f, dxpl_id, H5AC_BT, cur->addr, type, udata);
+	bt = H5AC_protect(f, dxpl_id, H5AC_BT, cur->addr, type, udata, H5AC_READ);
 	assert(bt);
 
 	/* Check node header */
diff --git a/src/H5FPclient.c b/src/H5FPclient.c
index df29015..f14b103 100644
--- a/src/H5FPclient.c
+++ b/src/H5FPclient.c
@@ -285,7 +285,7 @@ done:
  */
 herr_t
 H5FP_request_read_metadata(H5FD_t *file, unsigned file_id, hid_t dxpl_id,
-                           H5FD_mem_t UNUSED mem_type, MPI_Offset addr,
+                           H5FD_mem_t UNUSED mem_type, haddr_t addr,
                            size_t size, uint8_t **buf, int *bytes_read,
                            unsigned *req_id, H5FP_status_t *status)
 {
@@ -385,7 +385,7 @@ done:
  */
 herr_t
 H5FP_request_write_metadata(H5FD_t *file, unsigned file_id, hid_t dxpl_id,
-                            H5FD_mem_t mem_type, MPI_Offset addr,
+                            H5FD_mem_t mem_type, haddr_t addr,
                             int mdata_size, const char *mdata,
                             unsigned *req_id, H5FP_status_t *status)
 {
diff --git a/src/H5FPprivate.h b/src/H5FPprivate.h
index 0bc03c3..ec28f67 100644
--- a/src/H5FPprivate.h
+++ b/src/H5FPprivate.h
@@ -219,7 +219,7 @@ typedef struct {
     H5FP_status_t   status;     /* Status of the request                    */
     H5FD_mem_t      mem_type;   /* Type of memory updated, if req'd         */
     unsigned        md_size;    /* Size of the metadata sent in next msg    */
-    MPI_Offset      addr;       /* Address of the metadata                  */
+    haddr_t         addr;       /* Address of the metadata                  */
 } H5FP_read_t;
 
 extern MPI_Datatype H5FP_read;  /* MPI datatype for the H5FP_read obj       */
@@ -273,11 +273,11 @@ extern herr_t H5FP_request_release_lock(unsigned sap_file_id, hobj_ref_t oid,
                                         int last, unsigned *req_id,
                                         H5FP_status_t *status);
 extern herr_t H5FP_request_read_metadata(H5FD_t *file, unsigned sap_file_id, hid_t dxpl_id,
-                                         H5FD_mem_t mem_type, MPI_Offset addr,
+                                         H5FD_mem_t mem_type, haddr_t addr,
                                          size_t size, uint8_t **buf, int *bytes_read,
                                          unsigned *req_id, H5FP_status_t *status);
 extern herr_t H5FP_request_write_metadata(H5FD_t *file, unsigned file_id, hid_t dxpl_id,
-                                          H5FD_mem_t mem_type, MPI_Offset addr,
+                                          H5FD_mem_t mem_type, haddr_t addr,
                                           int mdata_size, const char *mdata,
                                           unsigned *req_id, H5FP_status_t *status);
 extern herr_t H5FP_request_flush_metadata(H5FD_t *file, unsigned file_id,
diff --git a/src/H5Gnode.c b/src/H5Gnode.c
index 875c4c4..36e876b 100644
--- a/src/H5Gnode.c
+++ b/src/H5Gnode.c
@@ -820,7 +820,7 @@ H5G_node_found(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void UNUSED *_lt_key
     /*
      * Load the symbol table node for exclusive access.
      */
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, FAIL, "unable to protect symbol table node");
 
     /* Get base address of heap */
@@ -933,7 +933,7 @@ H5G_node_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr, void UNUSED *_lt_key,
     /*
      * Load the symbol node.
      */
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to protect symbol table node");
 
     /* Get base address of heap */
@@ -978,7 +978,7 @@ H5G_node_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr, void UNUSED *_lt_key,
 			    new_node_p/*out*/)<0)
 	    HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5B_INS_ERROR, "unable to split symbol table node");
 
-	if (NULL == (snrt = H5AC_protect(f, dxpl_id, H5AC_SNODE, *new_node_p, NULL, NULL)))
+	if (NULL == (snrt = H5AC_protect(f, dxpl_id, H5AC_SNODE, *new_node_p, NULL, NULL, H5AC_WRITE)))
 	    HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to split symbol table node");
 
 	HDmemcpy(snrt->entry, sn->entry + H5F_SYM_LEAF_K(f),
@@ -1105,7 +1105,7 @@ H5G_node_remove(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key/*in,out*/,
     assert(bt_udata);
 
     /* Load the symbol table */
-    if (NULL==(sn=H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL==(sn=H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_INS_ERROR, "unable to protect symbol table node");
 
     /* Get base address of heap */
@@ -1286,7 +1286,7 @@ H5G_node_iterate (H5F_t *f, hid_t dxpl_id, void UNUSED *_lt_key, haddr_t addr,
      * Save information about the symbol table node since we can't lock it
      * because we're about to call an application function.
      */
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_ITER_ERROR, "unable to load symbol table node");
     nsyms = sn->nsyms;
     if (NULL==(name_off = H5MM_malloc (nsyms*sizeof(name_off[0]))))
@@ -1372,7 +1372,7 @@ H5G_node_sumup(H5F_t *f, hid_t dxpl_id, void UNUSED *_lt_key, haddr_t addr,
     assert(num_objs);
 
     /* Find the object node and add the number of symbol entries. */
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_ITER_ERROR, "unable to load symbol table node");
 
     *num_objs += sn->nsyms;
@@ -1423,7 +1423,7 @@ H5G_node_name(H5F_t *f, hid_t dxpl_id, void UNUSED *_lt_key, haddr_t addr,
     assert(H5F_addr_defined(addr));
     assert(bt_udata);
 
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_ITER_ERROR, "unable to load symbol table node");
     
     /* Find the node, locate the object symbol table entry and retrieve the name */ 
@@ -1480,7 +1480,7 @@ H5G_node_type(H5F_t *f, hid_t dxpl_id, void UNUSED *_lt_key, haddr_t addr,
     assert(bt_udata);
 
     /* Find the node, locate the object symbol table entry and retrieve the type */ 
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL)))
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_SYM, H5E_CANTLOAD, H5B_ITER_ERROR, "unable to load symbol table node");
 
     if(bt_udata->idx >= bt_udata->num_objs && bt_udata->idx < (bt_udata->num_objs+sn->nsyms)) {
@@ -1542,7 +1542,7 @@ H5G_node_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent,
      * If we couldn't load the symbol table node, then try loading the
      * B-tree node.
      */
-    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL))) {
+    if (NULL == (sn = H5AC_protect(f, dxpl_id, H5AC_SNODE, addr, NULL, NULL, H5AC_READ))) {
         H5G_bt_ud1_t	udata;		/*data to pass through B-tree	*/
 
         H5E_clear(NULL); /* discard that error */
@@ -1578,6 +1578,9 @@ H5G_node_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent,
     sn = NULL;
 
 done:
+    if (sn && H5AC_unprotect(f, dxpl_id, H5AC_SNODE, addr, sn, FALSE) < 0)
+	HDONE_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to release symbol table node");
+
     FUNC_LEAVE_NOAPI(ret_value);
 }
 
diff --git a/src/H5HG.c b/src/H5HG.c
index 922c2ca..096c075 100644
--- a/src/H5HG.c
+++ b/src/H5HG.c
@@ -765,7 +765,7 @@ H5HG_peek (H5F_t *f, hid_t dxpl_id, H5HG_t *hobj)
     assert (hobj);
 
     /* Load the heap and return a pointer to the object */
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR (H5E_HEAP, H5E_CANTLOAD, NULL, "unable to load heap");
 
     assert (hobj->idx>0 && hobj->idx<heap->nalloc);
@@ -834,7 +834,7 @@ H5HG_read (H5F_t *f, hid_t dxpl_id, H5HG_t *hobj, void *object/*out*/)
     assert (hobj);
 
     /* Load the heap */
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR (H5E_HEAP, H5E_CANTLOAD, NULL, "unable to load heap");
 
     assert (hobj->idx>0 && hobj->idx<heap->nalloc);
@@ -914,7 +914,7 @@ H5HG_link (H5F_t *f, hid_t dxpl_id, H5HG_t *hobj, int adjust)
 	HGOTO_ERROR (H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file");
 
     /* Load the heap */
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL, H5AC_WRITE)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load heap");
 
     assert (hobj->idx>0 && hobj->idx<heap->nalloc);
@@ -972,7 +972,7 @@ H5HG_remove (H5F_t *f, hid_t dxpl_id, H5HG_t *hobj)
         HGOTO_ERROR (H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file");
 
     /* Load the heap */
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_GHEAP, hobj->addr, NULL, NULL, H5AC_WRITE)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load heap");
 
     assert (hobj->idx>0 && hobj->idx<heap->nalloc);
diff --git a/src/H5HGdbg.c b/src/H5HGdbg.c
index c8afd85..4e7b8a8 100644
--- a/src/H5HGdbg.c
+++ b/src/H5HGdbg.c
@@ -73,7 +73,7 @@ H5HG_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent,
     assert(indent >= 0);
     assert(fwidth >= 0);
 
-    if (NULL == (h = H5AC_protect(f, dxpl_id, H5AC_GHEAP, addr, NULL, NULL)))
+    if (NULL == (h = H5AC_protect(f, dxpl_id, H5AC_GHEAP, addr, NULL, NULL, H5AC_READ)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load global heap collection");
 
     fprintf(stream, "%*sGlobal Heap Collection...\n", indent, "");
diff --git a/src/H5HL.c b/src/H5HL.c
index 332adf4..ea08e47 100644
--- a/src/H5HL.c
+++ b/src/H5HL.c
@@ -629,7 +629,7 @@ H5HL_read(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t offset, size_t size, voi
     assert(f);
     assert (H5F_addr_defined(addr));
 
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "unable to load heap");
 
     assert(offset < heap->mem_alloc);
@@ -696,7 +696,7 @@ H5HL_peek(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t offset)
     assert(f);
     assert(H5F_addr_defined(addr));
 
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_READ)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "unable to load heap");
 
     assert(offset < heap->mem_alloc);
@@ -784,7 +784,7 @@ H5HL_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t buf_size, const void *
     if (0==(f->intent & H5F_ACC_RDWR))
 	HGOTO_ERROR (H5E_HEAP, H5E_WRITEERROR, (size_t)(-1), "no write intent on file");
 
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_HEAP, H5E_PROTECT, (size_t)(-1), "unable to load heap");
 
     ++heap->cache_info.dirty;
@@ -954,7 +954,7 @@ H5HL_write(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t offset, size_t size, co
     if (0==(f->intent & H5F_ACC_RDWR))
 	HGOTO_ERROR (H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file");
 
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_HEAP, H5E_PROTECT, FAIL, "unable to load heap");
 
     assert(offset < heap->mem_alloc);
@@ -1019,7 +1019,7 @@ H5HL_remove(H5F_t *f, hid_t dxpl_id, haddr_t addr, size_t offset, size_t size)
 
     size = H5HL_ALIGN (size);
 
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_HEAP, H5E_PROTECT, FAIL, "unable to load heap");
 
     assert(offset < heap->mem_alloc);
@@ -1144,7 +1144,7 @@ H5HL_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
     sizeof_hdr= H5HL_SIZEOF_HDR(f);
 
     /* Get heap pointer */
-    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (heap = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load heap");
 
     /* Check if the heap is contiguous on disk */
diff --git a/src/H5HLdbg.c b/src/H5HLdbg.c
index 0277044..adc98fc 100644
--- a/src/H5HLdbg.c
+++ b/src/H5HLdbg.c
@@ -71,7 +71,7 @@ H5HL_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent, int
     assert(indent >= 0);
     assert(fwidth >= 0);
 
-    if (NULL == (h = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL)))
+    if (NULL == (h = H5AC_protect(f, dxpl_id, H5AC_LHEAP, addr, NULL, NULL, H5AC_READ)))
         HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, FAIL, "unable to load heap");
 
     fprintf(stream, "%*sLocal Heap...\n", indent, "");
diff --git a/src/H5O.c b/src/H5O.c
index 14dfd74..048386d 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -1209,7 +1209,7 @@ H5O_link(H5G_entry_t *ent, int adjust, hid_t dxpl_id)
 
     /* get header */
     if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header,
-				   NULL, NULL)))
+				   NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* adjust link count */
@@ -1332,7 +1332,7 @@ H5O_count_real (H5G_entry_t *ent, const H5O_class_t *type, hid_t dxpl_id)
     assert (type);
 
     /* Load the object header */
-    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR (H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     for (u=acc=0; u<oh->nmesgs; u++) {
@@ -1436,7 +1436,7 @@ H5O_exists_real(H5G_entry_t *ent, const H5O_class_t *type, int sequence, hid_t d
     assert(sequence>=0);
 
     /* Load the object header */
-    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_READ)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* Scan through the messages looking for the right one */
@@ -1572,7 +1572,7 @@ H5O_read_real(H5G_entry_t *ent, const H5O_class_t *type, int sequence, void *mes
 	HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, NULL, "unable to find message in object header");
 
     /* copy the message to the user-supplied buffer */
-    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "unable to load object header");
     if (oh->mesg[idx].flags & H5O_FLAG_SHARED) {
 	/*
@@ -1658,7 +1658,7 @@ H5O_find_in_ohdr(H5F_t *f, hid_t dxpl_id, haddr_t addr, const H5O_class_t **type
     assert(type_p);
 
     /* Load the object header */
-    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, UFAIL, "unable to load object header");
 
     /* Scan through the messages looking for the right one */
@@ -1844,7 +1844,7 @@ H5O_modify_real(H5G_entry_t *ent, const H5O_class_t *type, int overwrite,
     if (0==(ent->file->intent & H5F_ACC_RDWR))
 	HGOTO_ERROR (H5E_OHDR, H5E_WRITEERROR, FAIL, "no write intent on file");
 
-    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* Count similar messages */
@@ -1989,7 +1989,7 @@ H5O_protect(H5G_entry_t *ent, hid_t dxpl_id)
     if (0==(ent->file->intent & H5F_ACC_RDWR))
 	HGOTO_ERROR (H5E_OHDR, H5E_WRITEERROR, NULL, "no write intent on file");
 
-    if (NULL == (ret_value = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (ret_value = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "unable to load object header");
 
 done:
@@ -2313,7 +2313,7 @@ H5O_touch(H5G_entry_t *ent, hbool_t force, hid_t dxpl_id)
 	HGOTO_ERROR(H5E_OHDR, H5E_WRITEERROR, FAIL, "no write intent on file");
 
     /* Get the object header */
-    if (NULL==(oh=H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL==(oh=H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* Create/Update the modification time message */
@@ -2417,7 +2417,7 @@ H5O_bogus(H5G_entry_t *ent, hid_t dxpl_id)
 	HGOTO_ERROR(H5E_OHDR, H5E_WRITEERROR, FAIL, "no write intent on file");
 
     /* Get the object header */
-    if (NULL==(oh=H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL==(oh=H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* Create the "bogus" message */
@@ -2534,7 +2534,7 @@ H5O_remove_real(H5G_entry_t *ent, const H5O_class_t *type, int sequence, hid_t d
 	HGOTO_ERROR (H5E_HEAP, H5E_WRITEERROR, FAIL, "no write intent on file");
 
     /* load the object header */
-    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(ent->file, dxpl_id, H5AC_OHDR, ent->header, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
     
     for (u = seq = 0; u < oh->nmesgs; u++) {
@@ -3163,7 +3163,7 @@ H5O_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
     assert(H5F_addr_defined(addr));
 
     /* Get the object header information */
-    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* Delete object */
@@ -3345,7 +3345,7 @@ H5O_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int f
     assert(indent >= 0);
     assert(fwidth >= 0);
 
-    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL)))
+    if (NULL == (oh = H5AC_protect(f, dxpl_id, H5AC_OHDR, addr, NULL, NULL, H5AC_WRITE)))
 	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header");
 
     /* debug */