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/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* 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.
*
* This program is distributed in the hope that it would 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 the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <xfs.h>
static DEFINE_MUTEX(uuid_monitor);
static int uuid_table_size;
static uuid_t *uuid_table;
/* IRIX interpretation of an uuid_t */
typedef struct {
__be32 uu_timelow;
__be16 uu_timemid;
__be16 uu_timehi;
__be16 uu_clockseq;
__be16 uu_node[3];
} xfs_uu_t;
/*
* uuid_getnodeuniq - obtain the node unique fields of a UUID.
*
* This is not in any way a standard or condoned UUID function;
* it just something that's needed for user-level file handles.
*/
void
uuid_getnodeuniq(uuid_t *uuid, int fsid [2])
{
xfs_uu_t *uup = (xfs_uu_t *)uuid;
fsid[0] = (be16_to_cpu(uup->uu_clockseq) << 16) |
be16_to_cpu(uup->uu_timemid);
fsid[1] = be32_to_cpu(uup->uu_timelow);
}
void
uuid_create_nil(uuid_t *uuid)
{
memset(uuid, 0, sizeof(*uuid));
}
int
uuid_is_nil(uuid_t *uuid)
{
int i;
char *cp = (char *)uuid;
if (uuid == NULL)
return 0;
/* implied check of version number here... */
for (i = 0; i < sizeof *uuid; i++)
if (*cp++) return 0; /* not nil */
return 1; /* is nil */
}
int
uuid_equal(uuid_t *uuid1, uuid_t *uuid2)
{
return memcmp(uuid1, uuid2, sizeof(uuid_t)) ? 0 : 1;
}
/*
* Given a 128-bit uuid, return a 64-bit value by adding the top and bottom
* 64-bit words. NOTE: This function can not be changed EVER. Although
* brain-dead, some applications depend on this 64-bit value remaining
* persistent. Specifically, DMI vendors store the value as a persistent
* filehandle.
*/
__uint64_t
uuid_hash64(uuid_t *uuid)
{
__uint64_t *sp = (__uint64_t *)uuid;
return sp[0] + sp[1];
}
int
uuid_table_insert(uuid_t *uuid)
{
int i, hole;
mutex_lock(&uuid_monitor);
for (i = 0, hole = -1; i < uuid_table_size; i++) {
if (uuid_is_nil(&uuid_table[i])) {
hole = i;
continue;
}
if (uuid_equal(uuid, &uuid_table[i])) {
mutex_unlock(&uuid_monitor);
return 0;
}
}
if (hole < 0) {
uuid_table = kmem_realloc(uuid_table,
(uuid_table_size + 1) * sizeof(*uuid_table),
uuid_table_size * sizeof(*uuid_table),
KM_SLEEP);
hole = uuid_table_size++;
}
uuid_table[hole] = *uuid;
mutex_unlock(&uuid_monitor);
return 1;
}
void
uuid_table_remove(uuid_t *uuid)
{
int i;
mutex_lock(&uuid_monitor);
for (i = 0; i < uuid_table_size; i++) {
if (uuid_is_nil(&uuid_table[i]))
continue;
if (!uuid_equal(uuid, &uuid_table[i]))
continue;
uuid_create_nil(&uuid_table[i]);
break;
}
ASSERT(i < uuid_table_size);
mutex_unlock(&uuid_monitor);
}
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