smb_query_information_disk.c revision 7b59d02d2a384be9a08087b14defadd214b3c1dd
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* SMB: query_information_disk
*
* The SMB_COM_QUERY_INFORMATION_DISK command is used to determine the
* capacity and remaining free space on the drive hosting the directory
* structure indicated by Tid in the SMB header.
*
* Client Request Description
* ================================== =================================
*
* UCHAR WordCount; Count of parameter words = 0
* USHORT ByteCount; Count of data bytes = 0
*
* Server Response Description
* ================================== =================================
*
* UCHAR WordCount; Count of parameter words = 5
* USHORT TotalUnits; Total allocation units per server
* USHORT BlocksPerUnit; Blocks per allocation unit
* USHORT BlockSize; Block size (in bytes)
* USHORT FreeUnits; Number of free units
* USHORT Reserved; Reserved (client should ignore)
* USHORT ByteCount; Count of data bytes = 0
*
* The blocking/allocation units used in this response may be independent
* of the actual physical or logical blocking/allocation algorithm(s) used
* internally by the server. However, they must accurately reflect the
* amount of space on the server.
*
* This SMB only returns 16 bits of information for each field, which may
* not be large enough for some disk systems. In particular TotalUnits is
* commonly > 64K. Fortunately, it turns out the all the client cares
* about is the total disk size, in bytes, and the free space, in bytes.
* So, it is reasonable for a server to adjust the relative values of
* BlocksPerUnit and BlockSize to accommodate. If after all adjustment,
* the numbers are still too high, the largest possible values for
* TotalUnit or FreeUnits (i.e. 0xFFFF) should be returned.
*/
#include <smbsrv/smb_incl.h>
#include <smbsrv/smb_fsops.h>
{
int rc;
unsigned long block_size, unit_size;
unsigned short blocks_per_unit, bytes_per_block;
unsigned short total_units, free_units;
return (SDRC_ERROR_REPLY);
}
if (rc != 0) {
return (SDRC_ERROR_REPLY);
}
unit_size = 1;
/*
* It seems that DOS clients cannot handle block sizes
* bigger than 512 KB. So we have to set the block size at
* most to 512
*/
while (block_size > 512) {
block_size >>= 1;
unit_size <<= 1;
}
/* adjust blocks and sizes until they fit into a word */
while (total_blocks >= 0xFFFF) {
total_blocks >>= 1;
free_blocks >>= 1;
unit_size >>= 1;
total_blocks = 0xFFFF;
free_blocks <<= 1;
break;
}
}
0xFFFF : (unsigned short)total_blocks;
0xFFFF : (unsigned short)free_blocks;
bytes_per_block = (unsigned short)block_size;
blocks_per_unit = (unsigned short)unit_size;
5,
total_units, /* total_units */
blocks_per_unit, /* blocks_per_unit */
bytes_per_block, /* blocksize */
free_units, /* free_units */
0); /* bcc */
}