[svn-r17365] Description:

	Final merge of changes from sblock_mdc branch back to trunk.  The superblock is now managed by the metadata cache.

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
        FreeBSD/64 6.3 (liberty) w/C++ & FORTRAN, in debug mode
        Linux/32 2.6 (kagiso) w/PGI compilers, w/C++ & FORTRAN, w/threadsafe,
                                in debug mode
        Linux/64-amd64 2.6 (smirom) w/Intel compilers w/default API=1.6.x,
                                w/C++ & FORTRAN, in production mode
        Solaris/32 2.10 (linew) w/deprecated symbols disabled, w/C++ & FORTRAN,
                                w/szip filter, in production mode
        Linux/64-ia64 2.6 (cobalt) w/Intel compilers, w/C++ & FORTRAN,
                                in production mode
        Linux/64-ia64 2.4 (tg-login3) w/parallel, w/FORTRAN, in production mode
        Mac OS X/32 10.5.8 (amazon) in debug mode
        Mac OS X/32 10.5.8 (amazon) w/C++ & FORTRAN, w/threadsafe,
                                in production mode

1 files changed, 854 insertions, 0 deletions

diff --git a/src/H5Fsuper_cache.c b/src/H5Fsuper_cache.c
new file mode 100644
index 0000000..7df8f31
--- /dev/null
+++ b/src/H5Fsuper_cache.c
@@ -0,0 +1,854 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */
+#define H5G_PACKAGE		/*suppress error about including H5Gpkg	  */
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5Fpkg.h"             /* File access				*/
+#include "H5FDprivate.h"	/* File drivers				*/
+#include "H5FLprivate.h"        /* Free Lists                           */
+#include "H5Gpkg.h"		/* Groups		  		*/
+#include "H5Iprivate.h"		/* IDs			  		*/
+#include "H5MMprivate.h"        /* Memory management                    */
+#include "H5Pprivate.h"		/* Property lists			*/
+#include "H5SMprivate.h"        /* Shared Object Header Messages        */
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+/* Maximum size of super-block buffers */
+#define H5F_MAX_SUPERBLOCK_SIZE  134
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+
+/********************/
+/* Package Typedefs */
+/********************/
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+/* Metadata cache (H5AC) callbacks */
+static H5F_super_t *H5F_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *udata1, void *udata2);
+static herr_t H5F_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5F_super_t *sblock);
+static herr_t H5F_sblock_dest(H5F_t *f, H5F_super_t * sblock);
+static herr_t H5F_sblock_clear(H5F_t *f, H5F_super_t *sblock, hbool_t destroy);
+static herr_t H5F_sblock_size(const H5F_t *f, const H5F_super_t *sblock, size_t *size_ptr);
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+/* H5F inherits cache-like properties from H5AC */
+const H5AC_class_t H5AC_SUPERBLOCK[1] = {{
+    H5AC_SUPERBLOCK_ID,
+    (H5AC_load_func_t)H5F_sblock_load,
+    (H5AC_flush_func_t)H5F_sblock_flush,
+    (H5AC_dest_func_t)H5F_sblock_dest,
+    (H5AC_clear_func_t)H5F_sblock_clear,
+    (H5AC_notify_func_t)NULL,
+    (H5AC_size_func_t)H5F_sblock_size,
+}};
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+/* Declare extern the free list to manage the H5F_super_t struct */
+H5FL_EXTERN(H5F_super_t);
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_sblock_load
+ *
+ * Purpose:     Loads the superblock from the file, and deserializes
+ *              its information into the H5F_super_t structure.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        NULL
+ *
+ * Programmer:  Mike McGreevy
+ *              mamcgree@hdfgroup.org
+ *              April 8, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static H5F_super_t *
+H5F_sblock_load(H5F_t *f, hid_t dxpl_id, haddr_t UNUSED addr, const void UNUSED *udata1, void *udata2/*out*/)
+{
+    H5F_super_t        *sblock = NULL;      /* File's superblock */
+    uint8_t             sbuf[H5F_MAX_SUPERBLOCK_SIZE];     /* Buffer for superblock */
+    H5P_genplist_t     *c_plist;            /* File creation property list  */
+    H5F_file_t         *shared;             /* shared part of `file'        */
+    H5FD_t             *lf;                 /* file driver part of `shared' */
+    haddr_t             stored_eoa;         /*relative end-of-addr in file  */
+    haddr_t             eof;                /*end of file address           */
+    size_t              sizeof_addr;        /* Size of offsets in the file (in bytes) */
+    size_t              sizeof_size;        /* Size of lengths in the file (in bytes) */
+    const size_t        fixed_size = H5F_SUPERBLOCK_FIXED_SIZE; /*fixed sizeof superblock   */
+    size_t              variable_size;      /*variable sizeof superblock    */
+    uint8_t            *p;                  /* Temporary pointer into encoding buffer */
+    unsigned            super_vers;         /* Superblock version          */
+    hbool_t            *dirtied = (hbool_t *)udata2;  /* Set up dirtied out value */
+    H5F_super_t        *ret_value;          /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_sblock_load)
+
+    /* Short cuts */
+    shared = f->shared;
+    lf = shared->lf;
+
+    /* Get the shared file creation property list */
+    if(NULL == (c_plist = (H5P_genplist_t *)H5I_object(shared->fcpl_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "can't get property list")
+
+    /* Allocate space for the superblock */
+    if(NULL == (sblock = H5FL_CALLOC(H5F_super_t)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+    
+    /* Read fixed-size portion of the superblock */
+    p = sbuf;
+    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, f->shared->super_addr + fixed_size) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
+    if(H5FD_read(lf, dxpl_id, H5FD_MEM_SUPER, f->shared->super_addr, fixed_size, p) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_READERROR, NULL, "unable to read superblock")
+
+    /* Skip over signature (already checked when locating the superblock) */
+    p += H5F_SIGNATURE_LEN;
+
+    /* Superblock version */
+    super_vers = *p++;
+    if(super_vers > HDF5_SUPERBLOCK_VERSION_LATEST)
+        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad superblock version number")
+    if(H5P_set(c_plist, H5F_CRT_SUPER_VERS_NAME, &super_vers) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set superblock version")
+
+    /* Record the superblock version */
+    sblock->super_vers = super_vers;
+
+    /* Sanity check */
+    HDassert(((size_t)(p - sbuf)) == fixed_size);
+
+    /* Determine the size of the variable-length part of the superblock */
+    variable_size = H5F_SUPERBLOCK_VARLEN_SIZE(super_vers, f);
+    HDassert(variable_size > 0);
+    HDassert(fixed_size + variable_size <= sizeof(sbuf));
+
+    /* Read in variable-sized portion of superblock */
+    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, f->shared->super_addr + fixed_size + variable_size) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
+    if(H5FD_read(lf, dxpl_id, H5FD_MEM_SUPER, f->shared->super_addr + fixed_size, variable_size, p) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read superblock")
+    /* Check for older version of superblock format */
+    if(super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+        uint32_t	status_flags;	    /* File status flags	   */
+        unsigned        btree_k[H5B_NUM_BTREE_ID];  /* B-tree internal node 'K' values */
+        unsigned        sym_leaf_k;         /* Symbol table leaf node's 'K' value */
+
+        /* Freespace version (hard-wired) */
+        if(HDF5_FREESPACE_VERSION != *p++)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad free space version number")
+
+        /* Root group version number (hard-wired) */
+        if(HDF5_OBJECTDIR_VERSION != *p++)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad object directory version number")
+
+        /* Skip over reserved byte */
+        p++;
+
+        /* Shared header version number (hard-wired) */
+        if(HDF5_SHAREDHEADER_VERSION != *p++)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad shared-header format version number")
+
+        /* Size of file addresses */
+        sizeof_addr = *p++;
+        if(sizeof_addr != 2 && sizeof_addr != 4 &&
+                sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
+        if(H5P_set(c_plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &sizeof_addr) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number in an address")
+        shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
+
+        /* Size of file sizes */
+        sizeof_size = *p++;
+        if(sizeof_size != 2 && sizeof_size != 4 &&
+                sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
+        if(H5P_set(c_plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &sizeof_size) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number for object size")
+        shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
+
+        /* Skip over reserved byte */
+        p++;
+
+        /* Various B-tree sizes */
+        UINT16DECODE(p, sym_leaf_k);
+        if(sym_leaf_k == 0)
+            HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad symbol table leaf node 1/2 rank")
+        if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &sym_leaf_k) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for symbol table leaf nodes")
+        sblock->sym_leaf_k = sym_leaf_k;    /* Keep a local copy also */
+
+        /* Need 'get' call to set other array values */
+        if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, btree_k) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "unable to get rank for btree internal nodes")
+        UINT16DECODE(p, btree_k[H5B_SNODE_ID]);
+        if(btree_k[H5B_SNODE_ID] == 0)
+            HGOTO_ERROR(H5E_FILE, H5E_BADRANGE, NULL, "bad 1/2 rank for btree internal nodes")
+        /*
+         * Delay setting the value in the property list until we've checked
+         * for the indexed storage B-tree internal 'K' value later.
+         */
+
+        /* File status flags (not really used yet) */
+        UINT32DECODE(p, status_flags);
+        HDassert(status_flags <= 255);
+        sblock->status_flags = (uint8_t)status_flags;
+        if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
+
+        /*
+         * If the superblock version # is greater than 0, read in the indexed
+         * storage B-tree internal 'K' value
+         */
+        if(super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
+            UINT16DECODE(p, btree_k[H5B_CHUNK_ID]);
+            /* Reserved bytes are present only in version 1 */
+            if(super_vers == HDF5_SUPERBLOCK_VERSION_1)
+                p += 2;   /* reserved */
+        } /* end if */
+        else
+            btree_k[H5B_CHUNK_ID] = HDF5_BTREE_CHUNK_IK_DEF;
+
+        /* Set the B-tree internal node values, etc */
+        if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, btree_k) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for btree internal nodes")
+        HDmemcpy(sblock->btree_k, btree_k, sizeof(unsigned) * (size_t)H5B_NUM_BTREE_ID);    /* Keep a local copy also */
+
+        /* Remainder of "variable-sized" portion of superblock */
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->base_addr/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->ext_addr/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &stored_eoa/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->driver_addr/*out*/);
+
+        /* Allocate space for the root group symbol table entry */
+        HDassert(!sblock->root_ent);
+        if(NULL == (sblock->root_ent = (H5G_entry_t *)H5MM_calloc(sizeof(H5G_entry_t))))
+            HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, NULL, "can't allocate space for root group symbol table entry")
+
+        /* decode the root group symbol table entry */
+        if(H5G_ent_decode(f, (const uint8_t **)&p, sblock->root_ent) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTDECODE, NULL, "can't decode root group symbol table entry")
+
+        /* Set the root group address to the correct value */
+        sblock->root_addr = sblock->root_ent->header;
+
+        /*
+         * Check if superblock address is different from base address and
+         * adjust base address and "end of address" address if so.
+         */
+        if(!H5F_addr_eq(f->shared->super_addr, sblock->base_addr)) {
+            /* Check if the superblock moved earlier in the file */
+            if(H5F_addr_lt(f->shared->super_addr, sblock->base_addr))
+                stored_eoa -= (sblock->base_addr - f->shared->super_addr);
+            else
+                /* The superblock moved later in the file */
+                stored_eoa += (f->shared->super_addr - sblock->base_addr);
+
+            sblock->base_addr = f->shared->super_addr;
+        } /* end if */
+
+        /* Set the base address for the file in the VFD now, after adjusting
+         *  space for possible offsets of the HDF5 data in the file.
+         */
+        if(H5FD_set_base_addr(lf, sblock->base_addr) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "failed to set base address for file driver")
+
+        /* This step is for h5repart tool only. If user wants to change file driver
+         *  from family to sec2 while using h5repart, set the driver address to
+         *  undefined to let the library ignore the family driver information saved
+         *  in the superblock.
+         */
+        if(H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
+            /* Eliminate the driver info */
+            sblock->driver_addr = HADDR_UNDEF;
+
+            /* Indicate that the superblock should be marked dirty */
+            *dirtied = TRUE;
+        } /* end if */
+
+        /* Decode the optional driver information block */
+        if(H5F_addr_defined(sblock->driver_addr)) {
+            uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];     /* Buffer for driver info block */
+            char drv_name[9];       /* Name of driver */
+            unsigned drv_vers;      /* Version of driver info block */
+            size_t drv_variable_size; /* Size of variable-length portion of driver info block, in bytes */
+
+            /* Read in fixed-sized portion of driver info block */
+            p = dbuf;
+            if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
+            if(H5FD_read(lf, dxpl_id, H5FD_MEM_SUPER, sblock->driver_addr, (size_t)H5F_DRVINFOBLOCK_HDR_SIZE, p) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read driver information block")
+
+            /* Version number */
+            drv_vers = *p++;
+            if(drv_vers != HDF5_DRIVERINFO_VERSION_0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "bad driver information block version number")
+
+            p += 3; /* reserved bytes */
+
+            /* Driver info size */
+            UINT32DECODE(p, drv_variable_size);
+
+            /* Sanity check */
+            HDassert(H5F_DRVINFOBLOCK_HDR_SIZE + drv_variable_size <= sizeof(dbuf));
+
+            /* Driver name and/or version */
+            HDstrncpy(drv_name, (const char *)p, (size_t)8);
+            drv_name[8] = '\0';
+            p += 8; /* advance past name/version */
+
+            /* Check if driver matches driver information saved. Unfortunately, we can't push this
+             * function to each specific driver because we're checking if the driver is correct.
+             */
+            if(!HDstrncmp(drv_name, "NCSAfami", (size_t)8) && HDstrcmp(lf->cls->name, "family"))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "family driver should be used")
+            if(!HDstrncmp(drv_name, "NCSAmult", (size_t)8) && HDstrcmp(lf->cls->name, "multi"))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "multi driver should be used")
+
+            /* Read in variable-sized portion of driver info block */
+            if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE + drv_variable_size) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "set end of space allocation request failed")
+            if(H5FD_read(lf, dxpl_id, H5FD_MEM_SUPER, sblock->driver_addr + H5F_DRVINFOBLOCK_HDR_SIZE, drv_variable_size, p) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read file driver information")
+
+            /* Decode driver information */
+            if(H5FD_sb_decode(lf, drv_name, p) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to decode driver information")
+        } /* end if */
+    } /* end if */
+    else {
+        uint32_t computed_chksum;       /* Computed checksum  */
+        uint32_t read_chksum;           /* Checksum read from file  */
+
+        /* Size of file addresses */
+        sizeof_addr = *p++;
+        if(sizeof_addr != 2 && sizeof_addr != 4 &&
+                sizeof_addr != 8 && sizeof_addr != 16 && sizeof_addr != 32)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number in an address")
+        if(H5P_set(c_plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &sizeof_addr) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number in an address")
+        shared->sizeof_addr = sizeof_addr;  /* Keep a local copy also */
+
+        /* Size of file sizes */
+        sizeof_size = *p++;
+        if(sizeof_size != 2 && sizeof_size != 4 &&
+                sizeof_size != 8 && sizeof_size != 16 && sizeof_size != 32)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad byte number for object size")
+        if(H5P_set(c_plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &sizeof_size) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set byte number for object size")
+        shared->sizeof_size = sizeof_size;  /* Keep a local copy also */
+
+        /* File status flags (not really used yet) */
+        sblock->status_flags = *p++;
+        if(sblock->status_flags & ~H5F_SUPER_ALL_FLAGS)
+            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad flag value for superblock")
+
+        /* Base, superblock extension, end of file & root group object header addresses */
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->base_addr/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->ext_addr/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &stored_eoa/*out*/);
+        H5F_addr_decode(f, (const uint8_t **)&p, &sblock->root_addr/*out*/);
+
+        /* Compute checksum for superblock */
+        computed_chksum = H5_checksum_metadata(sbuf, (size_t)(p - sbuf), 0);
+
+        /* Decode checksum */
+        UINT32DECODE(p, read_chksum);
+
+        /* Verify correct checksum */
+        if(read_chksum != computed_chksum)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "bad checksum on driver information block")
+
+        /*
+         * Check if superblock address is different from base address and
+         * adjust base address and "end of address" address if so.
+         */
+        if(!H5F_addr_eq(f->shared->super_addr, sblock->base_addr)) {
+            /* Check if the superblock moved earlier in the file */
+            if(H5F_addr_lt(f->shared->super_addr, sblock->base_addr))
+                stored_eoa -= (sblock->base_addr - f->shared->super_addr);
+            else
+                /* The superblock moved later in the file */
+                stored_eoa += (f->shared->super_addr - sblock->base_addr);
+
+            sblock->base_addr = f->shared->super_addr;
+        } /* end if */
+
+        /* Set the base address for the file in the VFD now, after adjusting
+         *  space for possible offsets of the HDF5 data in the file.
+         */
+        if(H5FD_set_base_addr(lf, sblock->base_addr) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "failed to set base address for file driver")
+
+        /* Get the B-tree internal node values, etc */
+        if(H5P_get(c_plist, H5F_CRT_BTREE_RANK_NAME, sblock->btree_k) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "unable to get rank for btree internal nodes")
+    } /* end else */
+
+    /*
+     * The user-defined data is the area of the file before the base
+     * address.
+     */
+    if(H5P_set(c_plist, H5F_CRT_USER_BLOCK_NAME, &sblock->base_addr) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set userblock size")
+
+    /*
+     * Make sure that the data is not truncated. One case where this is
+     * possible is if the first file of a family of files was opened
+     * individually.
+     */
+    if(HADDR_UNDEF == (eof = H5FD_get_eof(lf)))
+        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to determine file size")
+
+    /* (Account for the stored EOA being absolute offset -QAK) */
+    if((eof + sblock->base_addr) < stored_eoa)
+        HGOTO_ERROR(H5E_FILE, H5E_TRUNCATED, NULL, "truncated file")
+
+    /*
+     * Tell the file driver how much address space has already been
+     * allocated so that it knows how to allocate additional memory.
+     */
+    /* (Account for the stored EOA being absolute offset -NAF) */
+    if(H5FD_set_eoa(lf, H5FD_MEM_SUPER, stored_eoa - sblock->base_addr) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to set end-of-address marker for file")
+
+    /* Read the file's superblock extension, if there is one. */
+    if(H5F_addr_defined(sblock->ext_addr)) {
+        H5O_loc_t ext_loc;      /* "Object location" for superblock extension */
+        H5O_btreek_t btreek;    /* v1 B-tree 'K' value message from superblock extension */
+        H5O_drvinfo_t drvinfo;  /* Driver info message from superblock extension */
+        htri_t status;          /* Status for message existing */
+
+        /* Sanity check - superblock extension should only be defined for
+         *      superblock version >= 2.
+         */
+        HDassert(super_vers >= HDF5_SUPERBLOCK_VERSION_2);
+
+        /* Check for superblock extension being located "outside" the stored
+         *      'eoa' value, which can occur with the split/multi VFD.
+         */
+        if(H5F_addr_gt(sblock->ext_addr, stored_eoa)) {
+            /* Set the 'eoa' for the object header memory type large enough
+             *  to give some room for a reasonably sized superblock extension.
+             *  (This is _rather_ a kludge -QAK)
+             */
+            if(H5FD_set_eoa(lf, H5FD_MEM_OHDR, (haddr_t)(sblock->ext_addr + 1024)) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to set end-of-address marker for file")
+        } /* end if */
+
+        /* Open the superblock extension */
+	if(H5F_super_ext_open(f, sblock->ext_addr, &ext_loc) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, NULL, "unable to open file's superblock extension")
+
+        /* Check for the extension having a 'driver info' message */
+        if((status = H5O_msg_exists(&ext_loc, H5O_DRVINFO_ID, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to read object header")
+        if(status) {
+            /* Check for ignoring the driver info for this file */
+            if(H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
+                /* Indicate that the superblock should be marked dirty */
+                *dirtied = TRUE;
+            } /* end if */
+            else {
+                /* Retrieve the 'driver info' structure */
+                if(NULL == H5O_msg_read(&ext_loc, H5O_DRVINFO_ID, &drvinfo, dxpl_id))
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "driver info message not present")
+
+                /* Check if driver matches driver information saved. Unfortunately, we can't push this
+                 * function to each specific driver because we're checking if the driver is correct.
+                 */
+                if(!HDstrncmp(drvinfo.name, "NCSAfami", (size_t)8) && HDstrcmp(lf->cls->name, "family"))
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "family driver should be used")
+                if(!HDstrncmp(drvinfo.name, "NCSAmult", (size_t)8) && HDstrcmp(lf->cls->name, "multi"))
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "multi driver should be used")
+
+                /* Decode driver information */
+                if(H5FD_sb_decode(lf, drvinfo.name, drvinfo.buf) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to decode driver information")
+
+                /* Reset driver info message */
+                H5O_msg_reset(H5O_DRVINFO_ID, &drvinfo);
+            } /* end else */
+        } /* end if */
+
+        /* Read in the shared OH message information if there is any */
+        if(H5SM_get_info(&ext_loc, c_plist, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read SOHM table information")
+
+        /* Check for the extension having a 'v1 B-tree "K"' message */
+        if((status = H5O_msg_exists(&ext_loc, H5O_BTREEK_ID, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to read object header")
+        if(status) {
+            /* Retrieve the 'v1 B-tree "K"' structure */
+            if(NULL == H5O_msg_read(&ext_loc, H5O_BTREEK_ID, &btreek, dxpl_id))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "v1 B-tree 'K' info message not present")
+
+            /* Set non-default v1 B-tree 'K' value info from file */
+            sblock->btree_k[H5B_CHUNK_ID] = btreek.btree_k[H5B_CHUNK_ID];
+            sblock->btree_k[H5B_SNODE_ID] = btreek.btree_k[H5B_SNODE_ID];
+            sblock->sym_leaf_k = btreek.sym_leaf_k;
+
+            /* Set non-default v1 B-tree 'K' values in the property list */
+            if(H5P_set(c_plist, H5F_CRT_BTREE_RANK_NAME, btreek.btree_k) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for btree internal nodes")
+            if(H5P_set(c_plist, H5F_CRT_SYM_LEAF_NAME, &btreek.sym_leaf_k) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "unable to set rank for symbol table leaf nodes")
+        } /* end if */
+        else {
+            /* No non-default v1 B-tree 'K' value info in file, use defaults */
+            sblock->btree_k[H5B_CHUNK_ID] = HDF5_BTREE_CHUNK_IK_DEF;
+            sblock->btree_k[H5B_SNODE_ID] = HDF5_BTREE_SNODE_IK_DEF;
+            sblock->sym_leaf_k = H5F_CRT_SYM_LEAF_DEF;
+        } /* end if */
+
+        /* Close superblock extension */
+	if(H5F_super_ext_close(f, &ext_loc) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, NULL, "unable to close file's superblock extension")
+    } /* end if */
+
+    /* Set return value */
+    ret_value = sblock;
+
+done:
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5F_sblock_load() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_sblock_flush
+ *
+ * Purpose:     Flushes the superblock.
+ *
+ * Return:      Success:        SUCCEED
+ *              Failure:        NULL
+ *
+ * Programmer:  Mike McGreevy
+ *              mamcgree@hdfgroup.org
+ *              April 8, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_sblock_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5F_super_t *sblock)
+{
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_sblock_flush)
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(sblock);
+
+    if(sblock->cache_info.is_dirty) {
+        uint8_t         buf[H5F_MAX_SUPERBLOCK_SIZE + H5F_MAX_DRVINFOBLOCK_SIZE];  /* Superblock & driver info blockencoding buffer */
+        uint8_t        *p;                          /* Ptr into encoding buffer */
+        haddr_t         rel_eoa;                    /* Relative EOA for file */
+        size_t          superblock_size;            /* Size of superblock, in bytes */
+        size_t          driver_size;                /* Size of driver info block (bytes)*/
+
+        /* Encode the common portion of the file superblock for all versions */
+        p = buf;
+        HDmemcpy(p, H5F_SIGNATURE, (size_t)H5F_SIGNATURE_LEN);
+        p += H5F_SIGNATURE_LEN;
+        *p++ = (uint8_t)sblock->super_vers;
+    
+        /* Check for older version of superblock format */
+        if(sblock->super_vers < HDF5_SUPERBLOCK_VERSION_2) {
+            *p++ = (uint8_t)HDF5_FREESPACE_VERSION;     /* (hard-wired) */
+            *p++ = (uint8_t)HDF5_OBJECTDIR_VERSION;     /* (hard-wired) */
+            *p++ = 0;   /* reserved*/
+    
+            *p++ = (uint8_t)HDF5_SHAREDHEADER_VERSION;  /* (hard-wired) */
+            HDassert(H5F_SIZEOF_ADDR(f) <= 255);
+            *p++ = (uint8_t)H5F_SIZEOF_ADDR(f);
+            HDassert(H5F_SIZEOF_SIZE(f) <= 255);
+            *p++ = (uint8_t)H5F_SIZEOF_SIZE(f);
+            *p++ = 0;   /* reserved */
+    
+            UINT16ENCODE(p, sblock->sym_leaf_k);
+            UINT16ENCODE(p, sblock->btree_k[H5B_SNODE_ID]);
+            UINT32ENCODE(p, (uint32_t)sblock->status_flags);
+    
+            /*
+             * Versions of the superblock >0 have the indexed storage B-tree
+             * internal 'K' value stored
+             */
+            if(sblock->super_vers > HDF5_SUPERBLOCK_VERSION_DEF) {
+                UINT16ENCODE(p, sblock->btree_k[H5B_CHUNK_ID]);
+                *p++ = 0;   /*reserved */
+                *p++ = 0;   /*reserved */
+            } /* end if */
+    
+            H5F_addr_encode(f, &p, sblock->base_addr);
+            H5F_addr_encode(f, &p, sblock->ext_addr);
+            rel_eoa = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER);
+            H5F_addr_encode(f, &p, (rel_eoa + sblock->base_addr));
+            H5F_addr_encode(f, &p, sblock->driver_addr);
+            
+            /* Encode the root group object entry, including the cached stab info */
+            if(H5G_ent_encode(f, &p, sblock->root_ent) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTENCODE, FAIL, "can't encode root group symbol table entry")
+    
+            /* Encode the driver information block. */
+            H5_ASSIGN_OVERFLOW(driver_size, H5FD_sb_size(f->shared->lf), hsize_t, size_t);
+    
+            /* Checking whether driver block address is defined here is to handle backward
+             * compatibility.  If the file was created with v1.6 library or earlier and no
+             * driver info block was written in the superblock, we don't write it either even
+             * though there's some driver info.  Otherwise, the driver block extended will
+             * overwrite the (meta)data right after the superblock. This situation happens to
+             * the family driver particularly.  SLU - 2009/3/24 
+             */
+            if(driver_size > 0 && H5F_addr_defined(sblock->driver_addr)) {
+                char driver_name[9];    /* Name of driver, for driver info block */
+                uint8_t *dbuf = p;      /* Pointer to beginning of driver info */
+    
+                /* Encode the driver information block */
+                *p++ = HDF5_DRIVERINFO_VERSION_0; /* Version */
+                *p++ = 0; /* reserved */
+                *p++ = 0; /* reserved */
+                *p++ = 0; /* reserved */
+    
+                /* Driver info size, excluding header */
+                UINT32ENCODE(p, driver_size);
+
+                /* Encode driver-specific data */
+                if(H5FD_sb_encode(f->shared->lf, driver_name, dbuf + H5F_DRVINFOBLOCK_HDR_SIZE) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
+
+                /* Store driver name (set in 'H5FD_sb_encode' call above) */
+                HDmemcpy(p, driver_name, (size_t)8);
+    
+                /* Advance buffer pointer past name & variable-sized portion of driver info */
+                /* (for later use in computing the superblock size) */
+                p += 8 + driver_size;
+            } /* end if */
+        } /* end if */
+        else {
+            uint32_t        chksum;                 /* Checksum temporary variable      */
+            H5O_loc_t       *root_oloc;             /* Pointer to root group's object location */
+    
+            /* Size of file addresses & offsets, and status flags */
+            HDassert(H5F_SIZEOF_ADDR(f) <= 255);
+            *p++ = (uint8_t)H5F_SIZEOF_ADDR(f);
+            HDassert(H5F_SIZEOF_SIZE(f) <= 255);
+            *p++ = (uint8_t)H5F_SIZEOF_SIZE(f);
+            *p++ = sblock->status_flags;
+    
+            /* Base, superblock extension & end of file addresses */
+            H5F_addr_encode(f, &p, sblock->base_addr);
+            H5F_addr_encode(f, &p, sblock->ext_addr);
+            rel_eoa = H5FD_get_eoa(f->shared->lf, H5FD_MEM_SUPER);
+            H5F_addr_encode(f, &p, (rel_eoa + sblock->base_addr));
+    
+            /* Retrieve information for root group */
+            if(NULL == (root_oloc = H5G_oloc(f->shared->root_grp)))
+                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to retrieve root group information")
+    
+            /* Encode address of root group's object header */
+            H5F_addr_encode(f, &p, root_oloc->addr);
+    
+            /* Compute superblock checksum */
+            chksum = H5_checksum_metadata(buf, (H5F_SUPERBLOCK_SIZE(sblock->super_vers, f) - H5F_SIZEOF_CHKSUM), 0);
+    
+            /* Superblock checksum */
+            UINT32ENCODE(p, chksum);
+    
+            /* Sanity check */
+            HDassert((size_t)(p - buf) == H5F_SUPERBLOCK_SIZE(sblock->super_vers, f));
+        } /* end else */
+    
+        /* Retrieve the total size of the superblock info */
+        H5_ASSIGN_OVERFLOW(superblock_size, (p - buf), int, size_t);
+    
+        /* Double check we didn't overrun the block (unlikely) */
+        HDassert(superblock_size <= sizeof(buf));
+
+        /* Write superblock */
+        /* (always at relative address 0) */
+        if(H5FD_write(f->shared->lf, dxpl_id, H5FD_MEM_SUPER, (haddr_t)0, superblock_size, buf) < 0)
+            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to write superblock")
+    
+        /* Check for newer version of superblock format & superblock extension */
+        if(sblock->super_vers >= HDF5_SUPERBLOCK_VERSION_2 && H5F_addr_defined(sblock->ext_addr)) {
+            /* Check for ignoring the driver info for this file */
+            if(!H5F_HAS_FEATURE(f, H5FD_FEAT_IGNORE_DRVRINFO)) {
+                /* Check for driver info message */
+                H5_ASSIGN_OVERFLOW(driver_size, H5FD_sb_size(f->shared->lf), hsize_t, size_t);
+                if(driver_size > 0) {
+                    H5O_drvinfo_t drvinfo;      /* Driver info */
+                    uint8_t dbuf[H5F_MAX_DRVINFOBLOCK_SIZE];  /* Driver info block encoding buffer */
+        
+                    /* Sanity check */
+                    HDassert(driver_size <= H5F_MAX_DRVINFOBLOCK_SIZE);
+        
+                    /* Encode driver-specific data */
+                    if(H5FD_sb_encode(f->shared->lf, drvinfo.name, dbuf) < 0)
+                        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to encode driver information")
+        
+                    /* Write driver info information to the superblock extension */
+                    drvinfo.len = driver_size;
+                    drvinfo.buf = dbuf;
+                    if(H5F_super_ext_write_msg(f, dxpl_id, &drvinfo, H5O_DRVINFO_ID, FALSE) < 0)
+                        HGOTO_ERROR(H5E_FILE, H5E_WRITEERROR, FAIL, "unable to update driver info header message")
+                } /* end if */
+            } /* end if */
+        } /* end if */
+
+        /* Reset the dirty flag.  */
+        sblock->cache_info.is_dirty = FALSE;
+    } /* end if */
+
+    if(destroy)
+        if(H5F_sblock_dest(f, sblock) < 0)
+            HGOTO_ERROR(H5E_FSPACE, H5E_CLOSEERROR, FAIL, "can't close superblock")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5F_sblock_flush() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_sblock_dest
+ *
+ * Purpose:     Frees memory used by the superblock.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Mike McGreevy
+ *              April 8, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_sblock_dest(H5F_t UNUSED *f, H5F_super_t* sblock)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5F_sblock_dest)
+
+    /* Sanity check */
+    HDassert(sblock);
+
+    /* Free root group symbol table entry, if any */
+    sblock->root_ent = (H5G_entry_t *)H5MM_xfree(sblock->root_ent);
+
+    /* Free superblock */
+    sblock = (H5F_super_t *)H5FL_FREE(H5F_super_t, sblock);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F_sblock_dest() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_sblock_clear
+ *
+ * Purpose:     Mark the superblock as no longer being dirty.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Mike McGreevy
+ *              April 8, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_sblock_clear(H5F_t *f, H5F_super_t *sblock, hbool_t destroy)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_sblock_clear)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(sblock);
+
+    /* Reset the dirty flag.  */
+    sblock->cache_info.is_dirty = FALSE;
+
+    if(destroy)
+        if(H5F_sblock_dest(f, sblock) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTFREE, FAIL, "unable to delete superblock")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5F_sblock_clear() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_sblock_size
+ *
+ * Purpose:     Returns the size of the superblock encoded on disk.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Mike McGreevy
+ *              April 8, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_sblock_size(const H5F_t *f, const H5F_super_t *sblock, size_t *size_ptr)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5F_sblock_size)
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(sblock);
+    HDassert(size_ptr);
+
+    /* Set size value */
+    *size_ptr = H5F_SUPERBLOCK_SIZE(sblock->super_vers, f);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5F_sblock_size() */
+