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/*
*
* (C) Copyright IBM Corp. 2001, 2003
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Module: libcsm.so
*
* File: commit.c
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <plugin.h>
#include "csm_plugin.h"
/*
* Function: write_metadata
*
* Called with a CSM metadata storage object to commit to disk. A CSM metadata
* storage object holds a ptr in its private data to a CSM header that will be
* committed to disk. The size and location of the CSM header on disk? It is
* always equal to the size and location of the metadata storage object!
*/
int write_metadata( DISKSEG *md, LOGICALDISK *ld,
DISKSEG *seg, boolean backup )
{
int rc=0;
csm_header_t *hdr=NULL;
u_int32_t crc;
u_int32_t size = 0;
LOG_ENTRY();
LOG_DEBUG("writing metadata on object %s\n", ld->name);
hdr = (void *) calloc(1, (EVMS_VSECTOR_SIZE*md->size) );
if (hdr) {
memcpy( hdr,
((seg_private_data_t *)md->private_data)->hdr,
((seg_private_data_t *)md->private_data)->hdr->size );
size = hdr->size;
cpu_csm_header_to_disk( hdr );
hdr->crc = 0;
crc = EngFncs->calculate_CRC( EVMS_INITIAL_CRC,hdr,size );
hdr->crc = CPU_TO_DISK32(~crc);
if (backup) {
rc = EngFncs->save_metadata( seg->name, ld->name,
md->start, md->size, hdr );
} else {
rc = WRITE( ld, md->start, md->size, (void *) hdr );
}
if (rc) {
LOG_ERROR("ERROR--> WRITE METADATA TO LBA %"PRIu64" FAILED WITH RC= %d\n", md->start,rc);
}
free(hdr);
}
else {
rc = ENOMEM;
}
LOG_EXIT_INT(rc);
return rc;
}
/*
* Function: commit_csm_metadata
*
* Called by the CSM plug-in commit api with:
*
* (1) a dirty segment storage object
* (2) the logical disk the segment is found on
* (3) the current commit phase
*
* A CSM commit follows this logic:
*
* IF ... dirty_segment == a CSM metadata segment
* THEN ... IF metadata segments commit phase matches current commit phase
* THEN commit the metdata segment and mark it clean
* ELSE leave the metadata segment dirty for subsequent commit phases
* ELSE ... simply mark the storage object clean
*
* The result is that the all 3 CSM segments will be committed at an
* appropriate time. The data segment ... whenever it first appears. The
* 1st metadata segment during phase 1. The 2nd metadata segment during
* phase 2.
*/
int commit_csm_metadata( DISKSEG *seg, LOGICALDISK *ld, uint commit_phase )
{
int rc=0;
seg_private_data_t *pdata;
LOG_ENTRY();
REQUIRE(ld != NULL);
REQUIRE(seg != NULL);
pdata = (seg_private_data_t *) seg->private_data;
REQUIRE(pdata != NULL);
if ( seg->data_type == META_DATA_TYPE ) {
if ( pdata->commit_phase == commit_phase ) {
rc = write_metadata( seg, ld, NULL, FALSE );
if (!rc) {
seg->flags &= ~SOFLAG_DIRTY;
}
}
}
else {
seg->flags &= ~SOFLAG_DIRTY;
}
LOG_EXIT_INT(rc);
return rc;
}
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