kernel-ark/drivers/target/target_core_fabric_lib.c
Jörn Engel 8359cf43b9 target: remove useless casts
A reader should spend an extra moment whenever noticing a cast,
because either something special is going on that deserves extra
attention or, as is all too often the case, the code is wrong.

These casts, afaics, have all been useless.  They cast a foo* to a
foo*, cast a void* to the assigned type, cast a foo* to void*, before
assigning it to a void* variable, etc.

In a few cases I also removed an additional &...[0], which is equally
useless.

Lastly I added three FIXMEs where, to the best of my judgement, the
code appears to have a bug.  It would be good if someone could check
these.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:28:07 +00:00

453 lines
12 KiB
C

/*******************************************************************************
* Filename: target_core_fabric_lib.c
*
* This file contains generic high level protocol identifier and PR
* handlers for TCM fabric modules
*
* Copyright (c) 2010 Rising Tide Systems, Inc.
* Copyright (c) 2010 Linux-iSCSI.org
*
* Nicholas A. Bellinger <nab@linux-iscsi.org>
*
* 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.
*
******************************************************************************/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/spinlock.h>
#include <linux/export.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>
#include "target_core_internal.h"
#include "target_core_pr.h"
/*
* Handlers for Serial Attached SCSI (SAS)
*/
u8 sas_get_fabric_proto_ident(struct se_portal_group *se_tpg)
{
/*
* Return a SAS Serial SCSI Protocol identifier for loopback operations
* This is defined in section 7.5.1 Table 362 in spc4r17
*/
return 0x6;
}
EXPORT_SYMBOL(sas_get_fabric_proto_ident);
u32 sas_get_pr_transport_id(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code,
unsigned char *buf)
{
unsigned char *ptr;
int ret;
/*
* Set PROTOCOL IDENTIFIER to 6h for SAS
*/
buf[0] = 0x06;
/*
* From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
* over SAS Serial SCSI Protocol
*/
ptr = &se_nacl->initiatorname[4]; /* Skip over 'naa. prefix */
ret = hex2bin(&buf[4], ptr, 8);
if (ret < 0)
pr_debug("sas transport_id: invalid hex string\n");
/*
* The SAS Transport ID is a hardcoded 24-byte length
*/
return 24;
}
EXPORT_SYMBOL(sas_get_pr_transport_id);
u32 sas_get_pr_transport_id_len(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code)
{
*format_code = 0;
/*
* From spc4r17, 7.5.4.7 TransportID for initiator ports using SCSI
* over SAS Serial SCSI Protocol
*
* The SAS Transport ID is a hardcoded 24-byte length
*/
return 24;
}
EXPORT_SYMBOL(sas_get_pr_transport_id_len);
/*
* Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
* Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
*/
char *sas_parse_pr_out_transport_id(
struct se_portal_group *se_tpg,
const char *buf,
u32 *out_tid_len,
char **port_nexus_ptr)
{
/*
* Assume the FORMAT CODE 00b from spc4r17, 7.5.4.7 TransportID
* for initiator ports using SCSI over SAS Serial SCSI Protocol
*
* The TransportID for a SAS Initiator Port is of fixed size of
* 24 bytes, and SAS does not contain a I_T nexus identifier,
* so we return the **port_nexus_ptr set to NULL.
*/
*port_nexus_ptr = NULL;
*out_tid_len = 24;
return (char *)&buf[4];
}
EXPORT_SYMBOL(sas_parse_pr_out_transport_id);
/*
* Handlers for Fibre Channel Protocol (FCP)
*/
u8 fc_get_fabric_proto_ident(struct se_portal_group *se_tpg)
{
return 0x0; /* 0 = fcp-2 per SPC4 section 7.5.1 */
}
EXPORT_SYMBOL(fc_get_fabric_proto_ident);
u32 fc_get_pr_transport_id_len(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code)
{
*format_code = 0;
/*
* The FC Transport ID is a hardcoded 24-byte length
*/
return 24;
}
EXPORT_SYMBOL(fc_get_pr_transport_id_len);
u32 fc_get_pr_transport_id(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code,
unsigned char *buf)
{
unsigned char *ptr;
int i, ret;
u32 off = 8;
/*
* PROTOCOL IDENTIFIER is 0h for FCP-2
*
* From spc4r17, 7.5.4.2 TransportID for initiator ports using
* SCSI over Fibre Channel
*
* We convert the ASCII formatted N Port name into a binary
* encoded TransportID.
*/
ptr = &se_nacl->initiatorname[0];
for (i = 0; i < 24; ) {
if (!strncmp(&ptr[i], ":", 1)) {
i++;
continue;
}
ret = hex2bin(&buf[off++], &ptr[i], 1);
if (ret < 0)
pr_debug("fc transport_id: invalid hex string\n");
i += 2;
}
/*
* The FC Transport ID is a hardcoded 24-byte length
*/
return 24;
}
EXPORT_SYMBOL(fc_get_pr_transport_id);
char *fc_parse_pr_out_transport_id(
struct se_portal_group *se_tpg,
const char *buf,
u32 *out_tid_len,
char **port_nexus_ptr)
{
/*
* The TransportID for a FC N Port is of fixed size of
* 24 bytes, and FC does not contain a I_T nexus identifier,
* so we return the **port_nexus_ptr set to NULL.
*/
*port_nexus_ptr = NULL;
*out_tid_len = 24;
return (char *)&buf[8];
}
EXPORT_SYMBOL(fc_parse_pr_out_transport_id);
/*
* Handlers for Internet Small Computer Systems Interface (iSCSI)
*/
u8 iscsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
{
/*
* This value is defined for "Internet SCSI (iSCSI)"
* in spc4r17 section 7.5.1 Table 362
*/
return 0x5;
}
EXPORT_SYMBOL(iscsi_get_fabric_proto_ident);
u32 iscsi_get_pr_transport_id(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code,
unsigned char *buf)
{
u32 off = 4, padding = 0;
u16 len = 0;
spin_lock_irq(&se_nacl->nacl_sess_lock);
/*
* Set PROTOCOL IDENTIFIER to 5h for iSCSI
*/
buf[0] = 0x05;
/*
* From spc4r17 Section 7.5.4.6: TransportID for initiator
* ports using SCSI over iSCSI.
*
* The null-terminated, null-padded (see 4.4.2) ISCSI NAME field
* shall contain the iSCSI name of an iSCSI initiator node (see
* RFC 3720). The first ISCSI NAME field byte containing an ASCII
* null character terminates the ISCSI NAME field without regard for
* the specified length of the iSCSI TransportID or the contents of
* the ADDITIONAL LENGTH field.
*/
len = sprintf(&buf[off], "%s", se_nacl->initiatorname);
/*
* Add Extra byte for NULL terminator
*/
len++;
/*
* If there is ISID present with the registration and *format code == 1
* 1, use iSCSI Initiator port TransportID format.
*
* Otherwise use iSCSI Initiator device TransportID format that
* does not contain the ASCII encoded iSCSI Initiator iSID value
* provied by the iSCSi Initiator during the iSCSI login process.
*/
if ((*format_code == 1) && (pr_reg->isid_present_at_reg)) {
/*
* Set FORMAT CODE 01b for iSCSI Initiator port TransportID
* format.
*/
buf[0] |= 0x40;
/*
* From spc4r17 Section 7.5.4.6: TransportID for initiator
* ports using SCSI over iSCSI. Table 390
*
* The SEPARATOR field shall contain the five ASCII
* characters ",i,0x".
*
* The null-terminated, null-padded ISCSI INITIATOR SESSION ID
* field shall contain the iSCSI initiator session identifier
* (see RFC 3720) in the form of ASCII characters that are the
* hexadecimal digits converted from the binary iSCSI initiator
* session identifier value. The first ISCSI INITIATOR SESSION
* ID field byte containing an ASCII null character
*/
buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
buf[off+len] = 0x69; off++; /* ASCII Character: "i" */
buf[off+len] = 0x2c; off++; /* ASCII Character: "," */
buf[off+len] = 0x30; off++; /* ASCII Character: "0" */
buf[off+len] = 0x78; off++; /* ASCII Character: "x" */
len += 5;
buf[off+len] = pr_reg->pr_reg_isid[0]; off++;
buf[off+len] = pr_reg->pr_reg_isid[1]; off++;
buf[off+len] = pr_reg->pr_reg_isid[2]; off++;
buf[off+len] = pr_reg->pr_reg_isid[3]; off++;
buf[off+len] = pr_reg->pr_reg_isid[4]; off++;
buf[off+len] = pr_reg->pr_reg_isid[5]; off++;
buf[off+len] = '\0'; off++;
len += 7;
}
spin_unlock_irq(&se_nacl->nacl_sess_lock);
/*
* The ADDITIONAL LENGTH field specifies the number of bytes that follow
* in the TransportID. The additional length shall be at least 20 and
* shall be a multiple of four.
*/
padding = ((-len) & 3);
if (padding != 0)
len += padding;
buf[2] = ((len >> 8) & 0xff);
buf[3] = (len & 0xff);
/*
* Increment value for total payload + header length for
* full status descriptor
*/
len += 4;
return len;
}
EXPORT_SYMBOL(iscsi_get_pr_transport_id);
u32 iscsi_get_pr_transport_id_len(
struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code)
{
u32 len = 0, padding = 0;
spin_lock_irq(&se_nacl->nacl_sess_lock);
len = strlen(se_nacl->initiatorname);
/*
* Add extra byte for NULL terminator
*/
len++;
/*
* If there is ISID present with the registration, use format code:
* 01b: iSCSI Initiator port TransportID format
*
* If there is not an active iSCSI session, use format code:
* 00b: iSCSI Initiator device TransportID format
*/
if (pr_reg->isid_present_at_reg) {
len += 5; /* For ",i,0x" ASCII seperator */
len += 7; /* For iSCSI Initiator Session ID + Null terminator */
*format_code = 1;
} else
*format_code = 0;
spin_unlock_irq(&se_nacl->nacl_sess_lock);
/*
* The ADDITIONAL LENGTH field specifies the number of bytes that follow
* in the TransportID. The additional length shall be at least 20 and
* shall be a multiple of four.
*/
padding = ((-len) & 3);
if (padding != 0)
len += padding;
/*
* Increment value for total payload + header length for
* full status descriptor
*/
len += 4;
return len;
}
EXPORT_SYMBOL(iscsi_get_pr_transport_id_len);
char *iscsi_parse_pr_out_transport_id(
struct se_portal_group *se_tpg,
const char *buf,
u32 *out_tid_len,
char **port_nexus_ptr)
{
char *p;
u32 tid_len, padding;
int i;
u16 add_len;
u8 format_code = (buf[0] & 0xc0);
/*
* Check for FORMAT CODE 00b or 01b from spc4r17, section 7.5.4.6:
*
* TransportID for initiator ports using SCSI over iSCSI,
* from Table 388 -- iSCSI TransportID formats.
*
* 00b Initiator port is identified using the world wide unique
* SCSI device name of the iSCSI initiator
* device containing the initiator port (see table 389).
* 01b Initiator port is identified using the world wide unique
* initiator port identifier (see table 390).10b to 11b
* Reserved
*/
if ((format_code != 0x00) && (format_code != 0x40)) {
pr_err("Illegal format code: 0x%02x for iSCSI"
" Initiator Transport ID\n", format_code);
return NULL;
}
/*
* If the caller wants the TransportID Length, we set that value for the
* entire iSCSI Tarnsport ID now.
*/
if (out_tid_len != NULL) {
add_len = ((buf[2] >> 8) & 0xff);
add_len |= (buf[3] & 0xff);
tid_len = strlen(&buf[4]);
tid_len += 4; /* Add four bytes for iSCSI Transport ID header */
tid_len += 1; /* Add one byte for NULL terminator */
padding = ((-tid_len) & 3);
if (padding != 0)
tid_len += padding;
if ((add_len + 4) != tid_len) {
pr_debug("LIO-Target Extracted add_len: %hu "
"does not match calculated tid_len: %u,"
" using tid_len instead\n", add_len+4, tid_len);
*out_tid_len = tid_len;
} else
*out_tid_len = (add_len + 4);
}
/*
* Check for ',i,0x' seperator between iSCSI Name and iSCSI Initiator
* Session ID as defined in Table 390 - iSCSI initiator port TransportID
* format.
*/
if (format_code == 0x40) {
p = strstr(&buf[4], ",i,0x");
if (!p) {
pr_err("Unable to locate \",i,0x\" seperator"
" for Initiator port identifier: %s\n",
&buf[4]);
return NULL;
}
*p = '\0'; /* Terminate iSCSI Name */
p += 5; /* Skip over ",i,0x" seperator */
*port_nexus_ptr = p;
/*
* Go ahead and do the lower case conversion of the received
* 12 ASCII characters representing the ISID in the TransportID
* for comparison against the running iSCSI session's ISID from
* iscsi_target.c:lio_sess_get_initiator_sid()
*/
for (i = 0; i < 12; i++) {
if (isdigit(*p)) {
p++;
continue;
}
*p = tolower(*p);
p++;
}
}
return (char *)&buf[4];
}
EXPORT_SYMBOL(iscsi_parse_pr_out_transport_id);