linux/drivers/target/target_core_spc.c
Paolo Bonzini 32a8811ff1 target: support zero allocation length in REQUEST SENSE
Similar to INQUIRY and MODE SENSE, construct the sense data in a
buffer and later copy it to the scatterlist.  Do not do anything,
but still clear a pending unit attention condition, if the allocation
length is zero.

However, SPC tells us that "If a REQUEST SENSE command is terminated with
CHECK CONDITION status [and] the REQUEST SENSE command was received on
an I_T nexus with a pending unit attention condition (i.e., before the
device server reports CHECK CONDITION status), then the device server
shall not clear the pending unit attention condition."  Do the
transport_kmap_data_sg early to detect this case.

It also tells us "Device servers shall not adjust the additional sense
length to reflect truncation if the allocation length is less than the
sense data available", so do not do that!  Note that the err variable
is write-only.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-07 11:14:21 -07:00

1105 lines
31 KiB
C

/*
* SCSI Primary Commands (SPC) parsing and emulation.
*
* Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
* Copyright (c) 2005, 2006, 2007 SBE, Inc.
* Copyright (c) 2007-2010 Rising Tide Systems
* Copyright (c) 2008-2010 Linux-iSCSI.org
*
* Nicholas A. Bellinger <nab@kernel.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/module.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_tcq.h>
#include <target/target_core_base.h>
#include <target/target_core_backend.h>
#include <target/target_core_fabric.h>
#include "target_core_internal.h"
#include "target_core_alua.h"
#include "target_core_pr.h"
#include "target_core_ua.h"
static void spc_fill_alua_data(struct se_port *port, unsigned char *buf)
{
struct t10_alua_tg_pt_gp *tg_pt_gp;
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
/*
* Set SCCS for MAINTENANCE_IN + REPORT_TARGET_PORT_GROUPS.
*/
buf[5] = 0x80;
/*
* Set TPGS field for explict and/or implict ALUA access type
* and opteration.
*
* See spc4r17 section 6.4.2 Table 135
*/
if (!port)
return;
tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
if (!tg_pt_gp_mem)
return;
spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
if (tg_pt_gp)
buf[5] |= tg_pt_gp->tg_pt_gp_alua_access_type;
spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
}
static int spc_emulate_inquiry_std(struct se_cmd *cmd, char *buf)
{
struct se_lun *lun = cmd->se_lun;
struct se_device *dev = cmd->se_dev;
/* Set RMB (removable media) for tape devices */
if (dev->transport->get_device_type(dev) == TYPE_TAPE)
buf[1] = 0x80;
buf[2] = dev->transport->get_device_rev(dev);
/*
* NORMACA and HISUP = 0, RESPONSE DATA FORMAT = 2
*
* SPC4 says:
* A RESPONSE DATA FORMAT field set to 2h indicates that the
* standard INQUIRY data is in the format defined in this
* standard. Response data format values less than 2h are
* obsolete. Response data format values greater than 2h are
* reserved.
*/
buf[3] = 2;
/*
* Enable SCCS and TPGS fields for Emulated ALUA
*/
if (dev->se_sub_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED)
spc_fill_alua_data(lun->lun_sep, buf);
buf[7] = 0x2; /* CmdQue=1 */
snprintf(&buf[8], 8, "LIO-ORG");
snprintf(&buf[16], 16, "%s", dev->se_sub_dev->t10_wwn.model);
snprintf(&buf[32], 4, "%s", dev->se_sub_dev->t10_wwn.revision);
buf[4] = 31; /* Set additional length to 31 */
return 0;
}
/* unit serial number */
static int spc_emulate_evpd_80(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
u16 len = 0;
if (dev->se_sub_dev->su_dev_flags &
SDF_EMULATED_VPD_UNIT_SERIAL) {
u32 unit_serial_len;
unit_serial_len = strlen(dev->se_sub_dev->t10_wwn.unit_serial);
unit_serial_len++; /* For NULL Terminator */
len += sprintf(&buf[4], "%s",
dev->se_sub_dev->t10_wwn.unit_serial);
len++; /* Extra Byte for NULL Terminator */
buf[3] = len;
}
return 0;
}
static void spc_parse_naa_6h_vendor_specific(struct se_device *dev,
unsigned char *buf)
{
unsigned char *p = &dev->se_sub_dev->t10_wwn.unit_serial[0];
int cnt;
bool next = true;
/*
* Generate up to 36 bits of VENDOR SPECIFIC IDENTIFIER starting on
* byte 3 bit 3-0 for NAA IEEE Registered Extended DESIGNATOR field
* format, followed by 64 bits of VENDOR SPECIFIC IDENTIFIER EXTENSION
* to complete the payload. These are based from VPD=0x80 PRODUCT SERIAL
* NUMBER set via vpd_unit_serial in target_core_configfs.c to ensure
* per device uniqeness.
*/
for (cnt = 0; *p && cnt < 13; p++) {
int val = hex_to_bin(*p);
if (val < 0)
continue;
if (next) {
next = false;
buf[cnt++] |= val;
} else {
next = true;
buf[cnt] = val << 4;
}
}
}
/*
* Device identification VPD, for a complete list of
* DESIGNATOR TYPEs see spc4r17 Table 459.
*/
static int spc_emulate_evpd_83(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
struct se_lun *lun = cmd->se_lun;
struct se_port *port = NULL;
struct se_portal_group *tpg = NULL;
struct t10_alua_lu_gp_member *lu_gp_mem;
struct t10_alua_tg_pt_gp *tg_pt_gp;
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
unsigned char *prod = &dev->se_sub_dev->t10_wwn.model[0];
u32 prod_len;
u32 unit_serial_len, off = 0;
u16 len = 0, id_len;
off = 4;
/*
* NAA IEEE Registered Extended Assigned designator format, see
* spc4r17 section 7.7.3.6.5
*
* We depend upon a target_core_mod/ConfigFS provided
* /sys/kernel/config/target/core/$HBA/$DEV/wwn/vpd_unit_serial
* value in order to return the NAA id.
*/
if (!(dev->se_sub_dev->su_dev_flags & SDF_EMULATED_VPD_UNIT_SERIAL))
goto check_t10_vend_desc;
/* CODE SET == Binary */
buf[off++] = 0x1;
/* Set ASSOCIATION == addressed logical unit: 0)b */
buf[off] = 0x00;
/* Identifier/Designator type == NAA identifier */
buf[off++] |= 0x3;
off++;
/* Identifier/Designator length */
buf[off++] = 0x10;
/*
* Start NAA IEEE Registered Extended Identifier/Designator
*/
buf[off++] = (0x6 << 4);
/*
* Use OpenFabrics IEEE Company ID: 00 14 05
*/
buf[off++] = 0x01;
buf[off++] = 0x40;
buf[off] = (0x5 << 4);
/*
* Return ConfigFS Unit Serial Number information for
* VENDOR_SPECIFIC_IDENTIFIER and
* VENDOR_SPECIFIC_IDENTIFIER_EXTENTION
*/
spc_parse_naa_6h_vendor_specific(dev, &buf[off]);
len = 20;
off = (len + 4);
check_t10_vend_desc:
/*
* T10 Vendor Identifier Page, see spc4r17 section 7.7.3.4
*/
id_len = 8; /* For Vendor field */
prod_len = 4; /* For VPD Header */
prod_len += 8; /* For Vendor field */
prod_len += strlen(prod);
prod_len++; /* For : */
if (dev->se_sub_dev->su_dev_flags &
SDF_EMULATED_VPD_UNIT_SERIAL) {
unit_serial_len =
strlen(&dev->se_sub_dev->t10_wwn.unit_serial[0]);
unit_serial_len++; /* For NULL Terminator */
id_len += sprintf(&buf[off+12], "%s:%s", prod,
&dev->se_sub_dev->t10_wwn.unit_serial[0]);
}
buf[off] = 0x2; /* ASCII */
buf[off+1] = 0x1; /* T10 Vendor ID */
buf[off+2] = 0x0;
memcpy(&buf[off+4], "LIO-ORG", 8);
/* Extra Byte for NULL Terminator */
id_len++;
/* Identifier Length */
buf[off+3] = id_len;
/* Header size for Designation descriptor */
len += (id_len + 4);
off += (id_len + 4);
/*
* struct se_port is only set for INQUIRY VPD=1 through $FABRIC_MOD
*/
port = lun->lun_sep;
if (port) {
struct t10_alua_lu_gp *lu_gp;
u32 padding, scsi_name_len;
u16 lu_gp_id = 0;
u16 tg_pt_gp_id = 0;
u16 tpgt;
tpg = port->sep_tpg;
/*
* Relative target port identifer, see spc4r17
* section 7.7.3.7
*
* Get the PROTOCOL IDENTIFIER as defined by spc4r17
* section 7.5.1 Table 362
*/
buf[off] =
(tpg->se_tpg_tfo->get_fabric_proto_ident(tpg) << 4);
buf[off++] |= 0x1; /* CODE SET == Binary */
buf[off] = 0x80; /* Set PIV=1 */
/* Set ASSOCIATION == target port: 01b */
buf[off] |= 0x10;
/* DESIGNATOR TYPE == Relative target port identifer */
buf[off++] |= 0x4;
off++; /* Skip over Reserved */
buf[off++] = 4; /* DESIGNATOR LENGTH */
/* Skip over Obsolete field in RTPI payload
* in Table 472 */
off += 2;
buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
buf[off++] = (port->sep_rtpi & 0xff);
len += 8; /* Header size + Designation descriptor */
/*
* Target port group identifier, see spc4r17
* section 7.7.3.8
*
* Get the PROTOCOL IDENTIFIER as defined by spc4r17
* section 7.5.1 Table 362
*/
if (dev->se_sub_dev->t10_alua.alua_type !=
SPC3_ALUA_EMULATED)
goto check_scsi_name;
tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
if (!tg_pt_gp_mem)
goto check_lu_gp;
spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
if (!tg_pt_gp) {
spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
goto check_lu_gp;
}
tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
buf[off] =
(tpg->se_tpg_tfo->get_fabric_proto_ident(tpg) << 4);
buf[off++] |= 0x1; /* CODE SET == Binary */
buf[off] = 0x80; /* Set PIV=1 */
/* Set ASSOCIATION == target port: 01b */
buf[off] |= 0x10;
/* DESIGNATOR TYPE == Target port group identifier */
buf[off++] |= 0x5;
off++; /* Skip over Reserved */
buf[off++] = 4; /* DESIGNATOR LENGTH */
off += 2; /* Skip over Reserved Field */
buf[off++] = ((tg_pt_gp_id >> 8) & 0xff);
buf[off++] = (tg_pt_gp_id & 0xff);
len += 8; /* Header size + Designation descriptor */
/*
* Logical Unit Group identifier, see spc4r17
* section 7.7.3.8
*/
check_lu_gp:
lu_gp_mem = dev->dev_alua_lu_gp_mem;
if (!lu_gp_mem)
goto check_scsi_name;
spin_lock(&lu_gp_mem->lu_gp_mem_lock);
lu_gp = lu_gp_mem->lu_gp;
if (!lu_gp) {
spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
goto check_scsi_name;
}
lu_gp_id = lu_gp->lu_gp_id;
spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
buf[off++] |= 0x1; /* CODE SET == Binary */
/* DESIGNATOR TYPE == Logical Unit Group identifier */
buf[off++] |= 0x6;
off++; /* Skip over Reserved */
buf[off++] = 4; /* DESIGNATOR LENGTH */
off += 2; /* Skip over Reserved Field */
buf[off++] = ((lu_gp_id >> 8) & 0xff);
buf[off++] = (lu_gp_id & 0xff);
len += 8; /* Header size + Designation descriptor */
/*
* SCSI name string designator, see spc4r17
* section 7.7.3.11
*
* Get the PROTOCOL IDENTIFIER as defined by spc4r17
* section 7.5.1 Table 362
*/
check_scsi_name:
scsi_name_len = strlen(tpg->se_tpg_tfo->tpg_get_wwn(tpg));
/* UTF-8 ",t,0x<16-bit TPGT>" + NULL Terminator */
scsi_name_len += 10;
/* Check for 4-byte padding */
padding = ((-scsi_name_len) & 3);
if (padding != 0)
scsi_name_len += padding;
/* Header size + Designation descriptor */
scsi_name_len += 4;
buf[off] =
(tpg->se_tpg_tfo->get_fabric_proto_ident(tpg) << 4);
buf[off++] |= 0x3; /* CODE SET == UTF-8 */
buf[off] = 0x80; /* Set PIV=1 */
/* Set ASSOCIATION == target port: 01b */
buf[off] |= 0x10;
/* DESIGNATOR TYPE == SCSI name string */
buf[off++] |= 0x8;
off += 2; /* Skip over Reserved and length */
/*
* SCSI name string identifer containing, $FABRIC_MOD
* dependent information. For LIO-Target and iSCSI
* Target Port, this means "<iSCSI name>,t,0x<TPGT> in
* UTF-8 encoding.
*/
tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
scsi_name_len = sprintf(&buf[off], "%s,t,0x%04x",
tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpgt);
scsi_name_len += 1 /* Include NULL terminator */;
/*
* The null-terminated, null-padded (see 4.4.2) SCSI
* NAME STRING field contains a UTF-8 format string.
* The number of bytes in the SCSI NAME STRING field
* (i.e., the value in the DESIGNATOR LENGTH field)
* shall be no larger than 256 and shall be a multiple
* of four.
*/
if (padding)
scsi_name_len += padding;
buf[off-1] = scsi_name_len;
off += scsi_name_len;
/* Header size + Designation descriptor */
len += (scsi_name_len + 4);
}
buf[2] = ((len >> 8) & 0xff);
buf[3] = (len & 0xff); /* Page Length for VPD 0x83 */
return 0;
}
/* Extended INQUIRY Data VPD Page */
static int spc_emulate_evpd_86(struct se_cmd *cmd, unsigned char *buf)
{
buf[3] = 0x3c;
/* Set HEADSUP, ORDSUP, SIMPSUP */
buf[5] = 0x07;
/* If WriteCache emulation is enabled, set V_SUP */
if (cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0)
buf[6] = 0x01;
return 0;
}
/* Block Limits VPD page */
static int spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
u32 max_sectors;
int have_tp = 0;
/*
* Following spc3r22 section 6.5.3 Block Limits VPD page, when
* emulate_tpu=1 or emulate_tpws=1 we will be expect a
* different page length for Thin Provisioning.
*/
if (dev->se_sub_dev->se_dev_attrib.emulate_tpu || dev->se_sub_dev->se_dev_attrib.emulate_tpws)
have_tp = 1;
buf[0] = dev->transport->get_device_type(dev);
buf[3] = have_tp ? 0x3c : 0x10;
/* Set WSNZ to 1 */
buf[4] = 0x01;
/*
* Set OPTIMAL TRANSFER LENGTH GRANULARITY
*/
put_unaligned_be16(1, &buf[6]);
/*
* Set MAXIMUM TRANSFER LENGTH
*/
max_sectors = min(dev->se_sub_dev->se_dev_attrib.fabric_max_sectors,
dev->se_sub_dev->se_dev_attrib.hw_max_sectors);
put_unaligned_be32(max_sectors, &buf[8]);
/*
* Set OPTIMAL TRANSFER LENGTH
*/
put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.optimal_sectors, &buf[12]);
/*
* Exit now if we don't support TP.
*/
if (!have_tp)
return 0;
/*
* Set MAXIMUM UNMAP LBA COUNT
*/
put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count, &buf[20]);
/*
* Set MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT
*/
put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count,
&buf[24]);
/*
* Set OPTIMAL UNMAP GRANULARITY
*/
put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.unmap_granularity, &buf[28]);
/*
* UNMAP GRANULARITY ALIGNMENT
*/
put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment,
&buf[32]);
if (dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment != 0)
buf[32] |= 0x80; /* Set the UGAVALID bit */
return 0;
}
/* Block Device Characteristics VPD page */
static int spc_emulate_evpd_b1(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
buf[0] = dev->transport->get_device_type(dev);
buf[3] = 0x3c;
buf[5] = dev->se_sub_dev->se_dev_attrib.is_nonrot ? 1 : 0;
return 0;
}
/* Thin Provisioning VPD */
static int spc_emulate_evpd_b2(struct se_cmd *cmd, unsigned char *buf)
{
struct se_device *dev = cmd->se_dev;
/*
* From spc3r22 section 6.5.4 Thin Provisioning VPD page:
*
* The PAGE LENGTH field is defined in SPC-4. If the DP bit is set to
* zero, then the page length shall be set to 0004h. If the DP bit
* is set to one, then the page length shall be set to the value
* defined in table 162.
*/
buf[0] = dev->transport->get_device_type(dev);
/*
* Set Hardcoded length mentioned above for DP=0
*/
put_unaligned_be16(0x0004, &buf[2]);
/*
* The THRESHOLD EXPONENT field indicates the threshold set size in
* LBAs as a power of 2 (i.e., the threshold set size is equal to
* 2(threshold exponent)).
*
* Note that this is currently set to 0x00 as mkp says it will be
* changing again. We can enable this once it has settled in T10
* and is actually used by Linux/SCSI ML code.
*/
buf[4] = 0x00;
/*
* A TPU bit set to one indicates that the device server supports
* the UNMAP command (see 5.25). A TPU bit set to zero indicates
* that the device server does not support the UNMAP command.
*/
if (dev->se_sub_dev->se_dev_attrib.emulate_tpu != 0)
buf[5] = 0x80;
/*
* A TPWS bit set to one indicates that the device server supports
* the use of the WRITE SAME (16) command (see 5.42) to unmap LBAs.
* A TPWS bit set to zero indicates that the device server does not
* support the use of the WRITE SAME (16) command to unmap LBAs.
*/
if (dev->se_sub_dev->se_dev_attrib.emulate_tpws != 0)
buf[5] |= 0x40;
return 0;
}
static int spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf);
static struct {
uint8_t page;
int (*emulate)(struct se_cmd *, unsigned char *);
} evpd_handlers[] = {
{ .page = 0x00, .emulate = spc_emulate_evpd_00 },
{ .page = 0x80, .emulate = spc_emulate_evpd_80 },
{ .page = 0x83, .emulate = spc_emulate_evpd_83 },
{ .page = 0x86, .emulate = spc_emulate_evpd_86 },
{ .page = 0xb0, .emulate = spc_emulate_evpd_b0 },
{ .page = 0xb1, .emulate = spc_emulate_evpd_b1 },
{ .page = 0xb2, .emulate = spc_emulate_evpd_b2 },
};
/* supported vital product data pages */
static int spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf)
{
int p;
/*
* Only report the INQUIRY EVPD=1 pages after a valid NAA
* Registered Extended LUN WWN has been set via ConfigFS
* during device creation/restart.
*/
if (cmd->se_dev->se_sub_dev->su_dev_flags &
SDF_EMULATED_VPD_UNIT_SERIAL) {
buf[3] = ARRAY_SIZE(evpd_handlers);
for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p)
buf[p + 4] = evpd_handlers[p].page;
}
return 0;
}
static int spc_emulate_inquiry(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_portal_group *tpg = cmd->se_lun->lun_sep->sep_tpg;
unsigned char *buf, *map_buf;
unsigned char *cdb = cmd->t_task_cdb;
int p, ret;
map_buf = transport_kmap_data_sg(cmd);
/*
* If SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC is not set, then we
* know we actually allocated a full page. Otherwise, if the
* data buffer is too small, allocate a temporary buffer so we
* don't have to worry about overruns in all our INQUIRY
* emulation handling.
*/
if (cmd->data_length < SE_INQUIRY_BUF &&
(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)) {
buf = kzalloc(SE_INQUIRY_BUF, GFP_KERNEL);
if (!buf) {
transport_kunmap_data_sg(cmd);
cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
return -ENOMEM;
}
} else {
buf = map_buf;
}
if (dev == tpg->tpg_virt_lun0.lun_se_dev)
buf[0] = 0x3f; /* Not connected */
else
buf[0] = dev->transport->get_device_type(dev);
if (!(cdb[1] & 0x1)) {
if (cdb[2]) {
pr_err("INQUIRY with EVPD==0 but PAGE CODE=%02x\n",
cdb[2]);
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
ret = -EINVAL;
goto out;
}
ret = spc_emulate_inquiry_std(cmd, buf);
goto out;
}
for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p) {
if (cdb[2] == evpd_handlers[p].page) {
buf[1] = cdb[2];
ret = evpd_handlers[p].emulate(cmd, buf);
goto out;
}
}
pr_err("Unknown VPD Code: 0x%02x\n", cdb[2]);
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
ret = -EINVAL;
out:
if (buf != map_buf) {
memcpy(map_buf, buf, cmd->data_length);
kfree(buf);
}
transport_kunmap_data_sg(cmd);
if (!ret)
target_complete_cmd(cmd, GOOD);
return ret;
}
static int spc_modesense_rwrecovery(unsigned char *p)
{
p[0] = 0x01;
p[1] = 0x0a;
return 12;
}
static int spc_modesense_control(struct se_device *dev, unsigned char *p)
{
p[0] = 0x0a;
p[1] = 0x0a;
p[2] = 2;
/*
* From spc4r23, 7.4.7 Control mode page
*
* The QUEUE ALGORITHM MODIFIER field (see table 368) specifies
* restrictions on the algorithm used for reordering commands
* having the SIMPLE task attribute (see SAM-4).
*
* Table 368 -- QUEUE ALGORITHM MODIFIER field
* Code Description
* 0h Restricted reordering
* 1h Unrestricted reordering allowed
* 2h to 7h Reserved
* 8h to Fh Vendor specific
*
* A value of zero in the QUEUE ALGORITHM MODIFIER field specifies that
* the device server shall order the processing sequence of commands
* having the SIMPLE task attribute such that data integrity is maintained
* for that I_T nexus (i.e., if the transmission of new SCSI transport protocol
* requests is halted at any time, the final value of all data observable
* on the medium shall be the same as if all the commands had been processed
* with the ORDERED task attribute).
*
* A value of one in the QUEUE ALGORITHM MODIFIER field specifies that the
* device server may reorder the processing sequence of commands having the
* SIMPLE task attribute in any manner. Any data integrity exposures related to
* command sequence order shall be explicitly handled by the application client
* through the selection of appropriate ommands and task attributes.
*/
p[3] = (dev->se_sub_dev->se_dev_attrib.emulate_rest_reord == 1) ? 0x00 : 0x10;
/*
* From spc4r17, section 7.4.6 Control mode Page
*
* Unit Attention interlocks control (UN_INTLCK_CTRL) to code 00b
*
* 00b: The logical unit shall clear any unit attention condition
* reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
* status and shall not establish a unit attention condition when a com-
* mand is completed with BUSY, TASK SET FULL, or RESERVATION CONFLICT
* status.
*
* 10b: The logical unit shall not clear any unit attention condition
* reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
* status and shall not establish a unit attention condition when
* a command is completed with BUSY, TASK SET FULL, or RESERVATION
* CONFLICT status.
*
* 11b a The logical unit shall not clear any unit attention condition
* reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
* status and shall establish a unit attention condition for the
* initiator port associated with the I_T nexus on which the BUSY,
* TASK SET FULL, or RESERVATION CONFLICT status is being returned.
* Depending on the status, the additional sense code shall be set to
* PREVIOUS BUSY STATUS, PREVIOUS TASK SET FULL STATUS, or PREVIOUS
* RESERVATION CONFLICT STATUS. Until it is cleared by a REQUEST SENSE
* command, a unit attention condition shall be established only once
* for a BUSY, TASK SET FULL, or RESERVATION CONFLICT status regardless
* to the number of commands completed with one of those status codes.
*/
p[4] = (dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2) ? 0x30 :
(dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 1) ? 0x20 : 0x00;
/*
* From spc4r17, section 7.4.6 Control mode Page
*
* Task Aborted Status (TAS) bit set to zero.
*
* A task aborted status (TAS) bit set to zero specifies that aborted
* tasks shall be terminated by the device server without any response
* to the application client. A TAS bit set to one specifies that tasks
* aborted by the actions of an I_T nexus other than the I_T nexus on
* which the command was received shall be completed with TASK ABORTED
* status (see SAM-4).
*/
p[5] = (dev->se_sub_dev->se_dev_attrib.emulate_tas) ? 0x40 : 0x00;
p[8] = 0xff;
p[9] = 0xff;
p[11] = 30;
return 12;
}
static int spc_modesense_caching(struct se_device *dev, unsigned char *p)
{
p[0] = 0x08;
p[1] = 0x12;
if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0)
p[2] = 0x04; /* Write Cache Enable */
p[12] = 0x20; /* Disabled Read Ahead */
return 20;
}
static void spc_modesense_write_protect(unsigned char *buf, int type)
{
/*
* I believe that the WP bit (bit 7) in the mode header is the same for
* all device types..
*/
switch (type) {
case TYPE_DISK:
case TYPE_TAPE:
default:
buf[0] |= 0x80; /* WP bit */
break;
}
}
static void spc_modesense_dpofua(unsigned char *buf, int type)
{
switch (type) {
case TYPE_DISK:
buf[0] |= 0x10; /* DPOFUA bit */
break;
default:
break;
}
}
static int spc_emulate_modesense(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
char *cdb = cmd->t_task_cdb;
unsigned char *rbuf;
int type = dev->transport->get_device_type(dev);
int ten = (cmd->t_task_cdb[0] == MODE_SENSE_10);
int offset = ten ? 8 : 4;
int length = 0;
unsigned char buf[SE_MODE_PAGE_BUF];
memset(buf, 0, SE_MODE_PAGE_BUF);
switch (cdb[2] & 0x3f) {
case 0x01:
length = spc_modesense_rwrecovery(&buf[offset]);
break;
case 0x08:
length = spc_modesense_caching(dev, &buf[offset]);
break;
case 0x0a:
length = spc_modesense_control(dev, &buf[offset]);
break;
case 0x3f:
length = spc_modesense_rwrecovery(&buf[offset]);
length += spc_modesense_caching(dev, &buf[offset+length]);
length += spc_modesense_control(dev, &buf[offset+length]);
break;
default:
pr_err("MODE SENSE: unimplemented page/subpage: 0x%02x/0x%02x\n",
cdb[2] & 0x3f, cdb[3]);
cmd->scsi_sense_reason = TCM_UNKNOWN_MODE_PAGE;
return -EINVAL;
}
offset += length;
if (ten) {
offset -= 2;
buf[0] = (offset >> 8) & 0xff;
buf[1] = offset & 0xff;
if ((cmd->se_lun->lun_access & TRANSPORT_LUNFLAGS_READ_ONLY) ||
(cmd->se_deve &&
(cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY)))
spc_modesense_write_protect(&buf[3], type);
if ((dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0) &&
(dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0))
spc_modesense_dpofua(&buf[3], type);
if ((offset + 2) > cmd->data_length)
offset = cmd->data_length;
} else {
offset -= 1;
buf[0] = offset & 0xff;
if ((cmd->se_lun->lun_access & TRANSPORT_LUNFLAGS_READ_ONLY) ||
(cmd->se_deve &&
(cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY)))
spc_modesense_write_protect(&buf[2], type);
if ((dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0) &&
(dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0))
spc_modesense_dpofua(&buf[2], type);
if ((offset + 1) > cmd->data_length)
offset = cmd->data_length;
}
rbuf = transport_kmap_data_sg(cmd);
memcpy(rbuf, buf, offset);
transport_kunmap_data_sg(cmd);
target_complete_cmd(cmd, GOOD);
return 0;
}
static int spc_emulate_request_sense(struct se_cmd *cmd)
{
unsigned char *cdb = cmd->t_task_cdb;
unsigned char *rbuf;
u8 ua_asc = 0, ua_ascq = 0;
unsigned char buf[SE_SENSE_BUF];
memset(buf, 0, SE_SENSE_BUF);
if (cdb[1] & 0x01) {
pr_err("REQUEST_SENSE description emulation not"
" supported\n");
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -ENOSYS;
}
rbuf = transport_kmap_data_sg(cmd);
if (cmd->scsi_sense_reason != 0) {
/*
* Out of memory. We will fail with CHECK CONDITION, so
* we must not clear the unit attention condition.
*/
target_complete_cmd(cmd, CHECK_CONDITION);
return 0;
} else if (!core_scsi3_ua_clear_for_request_sense(cmd, &ua_asc, &ua_ascq)) {
/*
* CURRENT ERROR, UNIT ATTENTION
*/
buf[0] = 0x70;
buf[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
/*
* The Additional Sense Code (ASC) from the UNIT ATTENTION
*/
buf[SPC_ASC_KEY_OFFSET] = ua_asc;
buf[SPC_ASCQ_KEY_OFFSET] = ua_ascq;
buf[7] = 0x0A;
} else {
/*
* CURRENT ERROR, NO SENSE
*/
buf[0] = 0x70;
buf[SPC_SENSE_KEY_OFFSET] = NO_SENSE;
/*
* NO ADDITIONAL SENSE INFORMATION
*/
buf[SPC_ASC_KEY_OFFSET] = 0x00;
buf[7] = 0x0A;
}
if (rbuf) {
memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
transport_kunmap_data_sg(cmd);
}
target_complete_cmd(cmd, GOOD);
return 0;
}
static int spc_emulate_testunitready(struct se_cmd *cmd)
{
target_complete_cmd(cmd, GOOD);
return 0;
}
int spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
{
struct se_device *dev = cmd->se_dev;
struct se_subsystem_dev *su_dev = dev->se_sub_dev;
unsigned char *cdb = cmd->t_task_cdb;
switch (cdb[0]) {
case MODE_SELECT:
*size = cdb[4];
break;
case MODE_SELECT_10:
*size = (cdb[7] << 8) + cdb[8];
break;
case MODE_SENSE:
*size = cdb[4];
cmd->execute_cmd = spc_emulate_modesense;
break;
case MODE_SENSE_10:
*size = (cdb[7] << 8) + cdb[8];
cmd->execute_cmd = spc_emulate_modesense;
break;
case LOG_SELECT:
case LOG_SENSE:
*size = (cdb[7] << 8) + cdb[8];
break;
case PERSISTENT_RESERVE_IN:
if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
cmd->execute_cmd = target_scsi3_emulate_pr_in;
*size = (cdb[7] << 8) + cdb[8];
break;
case PERSISTENT_RESERVE_OUT:
if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
cmd->execute_cmd = target_scsi3_emulate_pr_out;
*size = (cdb[7] << 8) + cdb[8];
break;
case RELEASE:
case RELEASE_10:
if (cdb[0] == RELEASE_10)
*size = (cdb[7] << 8) | cdb[8];
else
*size = cmd->data_length;
if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
cmd->execute_cmd = target_scsi2_reservation_release;
break;
case RESERVE:
case RESERVE_10:
/*
* The SPC-2 RESERVE does not contain a size in the SCSI CDB.
* Assume the passthrough or $FABRIC_MOD will tell us about it.
*/
if (cdb[0] == RESERVE_10)
*size = (cdb[7] << 8) | cdb[8];
else
*size = cmd->data_length;
/*
* Setup the legacy emulated handler for SPC-2 and
* >= SPC-3 compatible reservation handling (CRH=1)
* Otherwise, we assume the underlying SCSI logic is
* is running in SPC_PASSTHROUGH, and wants reservations
* emulation disabled.
*/
if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
cmd->execute_cmd = target_scsi2_reservation_reserve;
break;
case REQUEST_SENSE:
*size = cdb[4];
cmd->execute_cmd = spc_emulate_request_sense;
break;
case INQUIRY:
*size = (cdb[3] << 8) + cdb[4];
/*
* Do implict HEAD_OF_QUEUE processing for INQUIRY.
* See spc4r17 section 5.3
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
cmd->sam_task_attr = MSG_HEAD_TAG;
cmd->execute_cmd = spc_emulate_inquiry;
break;
case SECURITY_PROTOCOL_IN:
case SECURITY_PROTOCOL_OUT:
*size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
break;
case EXTENDED_COPY:
case READ_ATTRIBUTE:
case RECEIVE_COPY_RESULTS:
case WRITE_ATTRIBUTE:
*size = (cdb[10] << 24) | (cdb[11] << 16) |
(cdb[12] << 8) | cdb[13];
break;
case RECEIVE_DIAGNOSTIC:
case SEND_DIAGNOSTIC:
*size = (cdb[3] << 8) | cdb[4];
break;
case WRITE_BUFFER:
*size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
break;
case REPORT_LUNS:
cmd->execute_cmd = target_report_luns;
*size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
/*
* Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
* See spc4r17 section 5.3
*/
if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
cmd->sam_task_attr = MSG_HEAD_TAG;
break;
case TEST_UNIT_READY:
cmd->execute_cmd = spc_emulate_testunitready;
*size = 0;
break;
case MAINTENANCE_IN:
if (dev->transport->get_device_type(dev) != TYPE_ROM) {
/*
* MAINTENANCE_IN from SCC-2
* Check for emulated MI_REPORT_TARGET_PGS
*/
if ((cdb[1] & 0x1f) == MI_REPORT_TARGET_PGS &&
su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
cmd->execute_cmd =
target_emulate_report_target_port_groups;
}
*size = get_unaligned_be32(&cdb[6]);
} else {
/*
* GPCMD_SEND_KEY from multi media commands
*/
*size = get_unaligned_be16(&cdb[8]);
}
break;
case MAINTENANCE_OUT:
if (dev->transport->get_device_type(dev) != TYPE_ROM) {
/*
* MAINTENANCE_OUT from SCC-2
* Check for emulated MO_SET_TARGET_PGS.
*/
if (cdb[1] == MO_SET_TARGET_PGS &&
su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
cmd->execute_cmd =
target_emulate_set_target_port_groups;
}
*size = get_unaligned_be32(&cdb[6]);
} else {
/*
* GPCMD_SEND_KEY from multi media commands
*/
*size = get_unaligned_be16(&cdb[8]);
}
break;
default:
pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
" 0x%02x, sending CHECK_CONDITION.\n",
cmd->se_tfo->get_fabric_name(), cdb[0]);
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
return -EINVAL;
}
return 0;
}
EXPORT_SYMBOL(spc_parse_cdb);