[mirror_ubuntu-jammy-kernel.git] / drivers / target / target_core_sbc.c

/*
 * SCSI Block Commands (SBC) 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 <linux/ratelimit.h>
#include <asm/unaligned.h>
#include <scsi/scsi.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_ua.h"


static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
{
	return cmd->se_dev->se_sub_dev->se_dev_attrib.block_size * sectors;
}

static int sbc_check_valid_sectors(struct se_cmd *cmd)
{
	struct se_device *dev = cmd->se_dev;
	unsigned long long end_lba;
	u32 sectors;

	sectors = cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size;
	end_lba = dev->transport->get_blocks(dev) + 1;

	if (cmd->t_task_lba + sectors > end_lba) {
		pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
			cmd->t_task_lba, sectors, end_lba);
		return -EINVAL;
	}

	return 0;
}

static inline u32 transport_get_sectors_6(unsigned char *cdb)
{
	/*
	 * Use 8-bit sector value.  SBC-3 says:
	 *
	 *   A TRANSFER LENGTH field set to zero specifies that 256
	 *   logical blocks shall be written.  Any other value
	 *   specifies the number of logical blocks that shall be
	 *   written.
	 */
	return cdb[4] ? : 256;
}

static inline u32 transport_get_sectors_10(unsigned char *cdb)
{
	return (u32)(cdb[7] << 8) + cdb[8];
}

static inline u32 transport_get_sectors_12(unsigned char *cdb)
{
	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
}

static inline u32 transport_get_sectors_16(unsigned char *cdb)
{
	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
		    (cdb[12] << 8) + cdb[13];
}

/*
 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 */
static inline u32 transport_get_sectors_32(unsigned char *cdb)
{
	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
		    (cdb[30] << 8) + cdb[31];

}

static inline u32 transport_lba_21(unsigned char *cdb)
{
	return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
}

static inline u32 transport_lba_32(unsigned char *cdb)
{
	return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
}

static inline unsigned long long transport_lba_64(unsigned char *cdb)
{
	unsigned int __v1, __v2;

	__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
	__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];

	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
}

/*
 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 */
static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
{
	unsigned int __v1, __v2;

	__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
	__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];

	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
}

static int sbc_write_same_supported(struct se_device *dev,
		unsigned char *flags)
{
	if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
		pr_err("WRITE_SAME PBDATA and LBDATA"
			" bits not supported for Block Discard"
			" Emulation\n");
		return -ENOSYS;
	}

	/*
	 * Currently for the emulated case we only accept
	 * tpws with the UNMAP=1 bit set.
	 */
	if (!(flags[0] & 0x08)) {
		pr_err("WRITE_SAME w/o UNMAP bit not"
			" supported for Block Discard Emulation\n");
		return -ENOSYS;
	}

	return 0;
}

static void xdreadwrite_callback(struct se_cmd *cmd)
{
	unsigned char *buf, *addr;
	struct scatterlist *sg;
	unsigned int offset;
	int i;
	int count;
	/*
	 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
	 *
	 * 1) read the specified logical block(s);
	 * 2) transfer logical blocks from the data-out buffer;
	 * 3) XOR the logical blocks transferred from the data-out buffer with
	 *    the logical blocks read, storing the resulting XOR data in a buffer;
	 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
	 *    blocks transferred from the data-out buffer; and
	 * 5) transfer the resulting XOR data to the data-in buffer.
	 */
	buf = kmalloc(cmd->data_length, GFP_KERNEL);
	if (!buf) {
		pr_err("Unable to allocate xor_callback buf\n");
		return;
	}
	/*
	 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
	 * into the locally allocated *buf
	 */
	sg_copy_to_buffer(cmd->t_data_sg,
			  cmd->t_data_nents,
			  buf,
			  cmd->data_length);

	/*
	 * Now perform the XOR against the BIDI read memory located at
	 * cmd->t_mem_bidi_list
	 */

	offset = 0;
	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
		addr = kmap_atomic(sg_page(sg));
		if (!addr)
			goto out;

		for (i = 0; i < sg->length; i++)
			*(addr + sg->offset + i) ^= *(buf + offset + i);

		offset += sg->length;
		kunmap_atomic(addr);
	}

out:
	kfree(buf);
}

int sbc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
{
	struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
	struct se_device *dev = cmd->se_dev;
	unsigned char *cdb = cmd->t_task_cdb;
	u32 sectors = 0;
	int ret;

	switch (cdb[0]) {
	case READ_6:
		sectors = transport_get_sectors_6(cdb);
		cmd->t_task_lba = transport_lba_21(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case READ_10:
		sectors = transport_get_sectors_10(cdb);
		cmd->t_task_lba = transport_lba_32(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case READ_12:
		sectors = transport_get_sectors_12(cdb);
		cmd->t_task_lba = transport_lba_32(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case READ_16:
		sectors = transport_get_sectors_16(cdb);
		cmd->t_task_lba = transport_lba_64(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case WRITE_6:
		sectors = transport_get_sectors_6(cdb);
		cmd->t_task_lba = transport_lba_21(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case WRITE_10:
	case WRITE_VERIFY:
		sectors = transport_get_sectors_10(cdb);
		cmd->t_task_lba = transport_lba_32(cdb);
		if (cdb[1] & 0x8)
			cmd->se_cmd_flags |= SCF_FUA;
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case WRITE_12:
		sectors = transport_get_sectors_12(cdb);
		cmd->t_task_lba = transport_lba_32(cdb);
		if (cdb[1] & 0x8)
			cmd->se_cmd_flags |= SCF_FUA;
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case WRITE_16:
		sectors = transport_get_sectors_16(cdb);
		cmd->t_task_lba = transport_lba_64(cdb);
		if (cdb[1] & 0x8)
			cmd->se_cmd_flags |= SCF_FUA;
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
		break;
	case XDWRITEREAD_10:
		if ((cmd->data_direction != DMA_TO_DEVICE) ||
		    !(cmd->se_cmd_flags & SCF_BIDI))
			goto out_invalid_cdb_field;
		sectors = transport_get_sectors_10(cdb);

		cmd->t_task_lba = transport_lba_32(cdb);
		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;

		/*
		 * Setup BIDI XOR callback to be run after I/O completion.
		 */
		cmd->transport_complete_callback = &xdreadwrite_callback;
		if (cdb[1] & 0x8)
			cmd->se_cmd_flags |= SCF_FUA;
		break;
	case VARIABLE_LENGTH_CMD:
	{
		u16 service_action = get_unaligned_be16(&cdb[8]);
		switch (service_action) {
		case XDWRITEREAD_32:
			sectors = transport_get_sectors_32(cdb);

			/*
			 * Use WRITE_32 and READ_32 opcodes for the emulated
			 * XDWRITE_READ_32 logic.
			 */
			cmd->t_task_lba = transport_lba_64_ext(cdb);
			cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;

			/*
			 * Setup BIDI XOR callback to be run during after I/O
			 * completion.
			 */
			cmd->transport_complete_callback = &xdreadwrite_callback;
			if (cdb[1] & 0x8)
				cmd->se_cmd_flags |= SCF_FUA;
			break;
		case WRITE_SAME_32:
			sectors = transport_get_sectors_32(cdb);
			if (!sectors) {
				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
				       " supported\n");
				goto out_invalid_cdb_field;
			}

			*size = sbc_get_size(cmd, 1);
			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);

			if (sbc_write_same_supported(dev, &cdb[10]) < 0)
				goto out_unsupported_cdb;
			cmd->execute_cmd = target_emulate_write_same;
			break;
		default:
			pr_err("VARIABLE_LENGTH_CMD service action"
				" 0x%04x not supported\n", service_action);
			goto out_unsupported_cdb;
		}
		break;
	}
	case READ_CAPACITY:
		*size = READ_CAP_LEN;
		cmd->execute_cmd = target_emulate_readcapacity;
		break;
	case SERVICE_ACTION_IN:
		switch (cmd->t_task_cdb[1] & 0x1f) {
		case SAI_READ_CAPACITY_16:
			cmd->execute_cmd = target_emulate_readcapacity_16;
			break;
		default:
			pr_err("Unsupported SA: 0x%02x\n",
				cmd->t_task_cdb[1] & 0x1f);
			goto out_invalid_cdb_field;
		}
		*size = (cdb[10] << 24) | (cdb[11] << 16) |
		       (cdb[12] << 8) | cdb[13];
		break;
	case SYNCHRONIZE_CACHE:
	case SYNCHRONIZE_CACHE_16:
		/*
		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
		 */
		if (cdb[0] == SYNCHRONIZE_CACHE) {
			sectors = transport_get_sectors_10(cdb);
			cmd->t_task_lba = transport_lba_32(cdb);
		} else {
			sectors = transport_get_sectors_16(cdb);
			cmd->t_task_lba = transport_lba_64(cdb);
		}

		*size = sbc_get_size(cmd, sectors);

		/*
		 * Check to ensure that LBA + Range does not exceed past end of
		 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
		 */
		if (cmd->t_task_lba || sectors) {
			if (sbc_check_valid_sectors(cmd) < 0)
				goto out_invalid_cdb_field;
		}
		cmd->execute_cmd = target_emulate_synchronize_cache;
		break;
	case UNMAP:
		*size = get_unaligned_be16(&cdb[7]);
		cmd->execute_cmd = target_emulate_unmap;
		break;
	case WRITE_SAME_16:
		sectors = transport_get_sectors_16(cdb);
		if (!sectors) {
			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
			goto out_invalid_cdb_field;
		}

		*size = sbc_get_size(cmd, 1);
		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);

		if (sbc_write_same_supported(dev, &cdb[1]) < 0)
			goto out_unsupported_cdb;
		cmd->execute_cmd = target_emulate_write_same;
		break;
	case WRITE_SAME:
		sectors = transport_get_sectors_10(cdb);
		if (!sectors) {
			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
			goto out_invalid_cdb_field;
		}

		*size = sbc_get_size(cmd, 1);
		cmd->t_task_lba = get_unaligned_be32(&cdb[2]);

		/*
		 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
		 * of byte 1 bit 3 UNMAP instead of original reserved field
		 */
		if (sbc_write_same_supported(dev, &cdb[1]) < 0)
			goto out_unsupported_cdb;
		cmd->execute_cmd = target_emulate_write_same;
		break;
	case VERIFY:
		*size = 0;
		cmd->execute_cmd = target_emulate_noop;
		break;
	default:
		ret = spc_parse_cdb(cmd, size, false);
		if (ret)
			return ret;
	}

	/* reject any command that we don't have a handler for */
	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
		goto out_unsupported_cdb;

	if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
		if (sectors > su_dev->se_dev_attrib.fabric_max_sectors) {
			printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
				" big sectors %u exceeds fabric_max_sectors:"
				" %u\n", cdb[0], sectors,
				su_dev->se_dev_attrib.fabric_max_sectors);
			goto out_invalid_cdb_field;
		}
		if (sectors > su_dev->se_dev_attrib.hw_max_sectors) {
			printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
				" big sectors %u exceeds backend hw_max_sectors:"
				" %u\n", cdb[0], sectors,
				su_dev->se_dev_attrib.hw_max_sectors);
			goto out_invalid_cdb_field;
		}

		*size = sbc_get_size(cmd, sectors);
	}

	return 0;

out_unsupported_cdb:
	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
	cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
	return -EINVAL;
out_invalid_cdb_field:
	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
	cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
	return -EINVAL;
}
EXPORT_SYMBOL(sbc_parse_cdb);
Commit	Line	Data
d6e0175c CH	1	/*
	2	* SCSI Block Commands (SBC) parsing and emulation.
	3	*
	4	* Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
	5	* Copyright (c) 2005, 2006, 2007 SBE, Inc.
	6	* Copyright (c) 2007-2010 Rising Tide Systems
	7	* Copyright (c) 2008-2010 Linux-iSCSI.org
	8	*
	9	* Nicholas A. Bellinger <nab@kernel.org>
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License as published by
	13	* the Free Software Foundation; either version 2 of the License, or
	14	* (at your option) any later version.
	15	*
	16	* This program is distributed in the hope that it will be useful,
	17	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	* GNU General Public License for more details.
	20	*
	21	* You should have received a copy of the GNU General Public License
	22	* along with this program; if not, write to the Free Software
	23	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	24	*/
	25
	26	#include <linux/kernel.h>
	27	#include <linux/module.h>
	28	#include <linux/ratelimit.h>
	29	#include <asm/unaligned.h>
	30	#include <scsi/scsi.h>
	31
	32	#include <target/target_core_base.h>
	33	#include <target/target_core_backend.h>
	34	#include <target/target_core_fabric.h>
	35
	36	#include "target_core_internal.h"
	37	#include "target_core_ua.h"
	38
	39
	40	static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
	41	{
	42	return cmd->se_dev->se_sub_dev->se_dev_attrib.block_size * sectors;
	43	}
	44
	45	static int sbc_check_valid_sectors(struct se_cmd *cmd)
	46	{
	47	struct se_device *dev = cmd->se_dev;
	48	unsigned long long end_lba;
	49	u32 sectors;
	50
	51	sectors = cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size;
	52	end_lba = dev->transport->get_blocks(dev) + 1;
	53
	54	if (cmd->t_task_lba + sectors > end_lba) {
	55	pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
	56	cmd->t_task_lba, sectors, end_lba);
	57	return -EINVAL;
	58	}
	59
	60	return 0;
	61	}
	62
	63	static inline u32 transport_get_sectors_6(unsigned char *cdb)
	64	{
65	/*
66	* Use 8-bit sector value. SBC-3 says:
67	*
68	* A TRANSFER LENGTH field set to zero specifies that 256
69	* logical blocks shall be written. Any other value
70	* specifies the number of logical blocks that shall be
71	* written.
72	*/
73	return cdb[4] ? : 256;
74	}
75
76	static inline u32 transport_get_sectors_10(unsigned char *cdb)
77	{
78	return (u32)(cdb[7] << 8) + cdb[8];
79	}
80
81	static inline u32 transport_get_sectors_12(unsigned char *cdb)
82	{
83	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
84	}
85
86	static inline u32 transport_get_sectors_16(unsigned char *cdb)
87	{
88	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
89	(cdb[12] << 8) + cdb[13];
90	}
91
92	/*
93	* Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
94	*/
95	static inline u32 transport_get_sectors_32(unsigned char *cdb)
96	{
97	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
98	(cdb[30] << 8) + cdb[31];
99
100	}
101
102	static inline u32 transport_lba_21(unsigned char *cdb)
103	{
104	return ((cdb[1] & 0x1f) << 16) \| (cdb[2] << 8) \| cdb[3];
105	}
106
107	static inline u32 transport_lba_32(unsigned char *cdb)
108	{
109	return (cdb[2] << 24) \| (cdb[3] << 16) \| (cdb[4] << 8) \| cdb[5];
110	}
111
112	static inline unsigned long long transport_lba_64(unsigned char *cdb)
113	{
114	unsigned int __v1, __v2;
115
116	__v1 = (cdb[2] << 24) \| (cdb[3] << 16) \| (cdb[4] << 8) \| cdb[5];
117	__v2 = (cdb[6] << 24) \| (cdb[7] << 16) \| (cdb[8] << 8) \| cdb[9];
118
119	return ((unsigned long long)__v2) \| (unsigned long long)__v1 << 32;
120	}
121
122	/*
123	* For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
124	*/
125	static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
126	{
127	unsigned int __v1, __v2;
128
129	__v1 = (cdb[12] << 24) \| (cdb[13] << 16) \| (cdb[14] << 8) \| cdb[15];
130	__v2 = (cdb[16] << 24) \| (cdb[17] << 16) \| (cdb[18] << 8) \| cdb[19];
131
132	return ((unsigned long long)__v2) \| (unsigned long long)__v1 << 32;
133	}
134
135	static int sbc_write_same_supported(struct se_device *dev,
136	unsigned char *flags)
137	{
138	if ((flags[0] & 0x04) \|\| (flags[0] & 0x02)) {
139	pr_err("WRITE_SAME PBDATA and LBDATA"
140	" bits not supported for Block Discard"
141	" Emulation\n");
142	return -ENOSYS;
143	}
144
145	/*
146	* Currently for the emulated case we only accept
147	* tpws with the UNMAP=1 bit set.
148	*/
149	if (!(flags[0] & 0x08)) {
150	pr_err("WRITE_SAME w/o UNMAP bit not"
151	" supported for Block Discard Emulation\n");
152	return -ENOSYS;
153	}
154
155	return 0;
156	}
157
158	static void xdreadwrite_callback(struct se_cmd *cmd)
159	{
160	unsigned char buf, addr;
161	struct scatterlist *sg;
162	unsigned int offset;
163	int i;
164	int count;
165	/*
166	* From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
167	*
168	* 1) read the specified logical block(s);
169	* 2) transfer logical blocks from the data-out buffer;
170	* 3) XOR the logical blocks transferred from the data-out buffer with
171	* the logical blocks read, storing the resulting XOR data in a buffer;
172	* 4) if the DISABLE WRITE bit is set to zero, then write the logical
173	* blocks transferred from the data-out buffer; and
174	* 5) transfer the resulting XOR data to the data-in buffer.
175	*/
176	buf = kmalloc(cmd->data_length, GFP_KERNEL);
177	if (!buf) {
178	pr_err("Unable to allocate xor_callback buf\n");
179	return;
180	}
181	/*
182	* Copy the scatterlist WRITE buffer located at cmd->t_data_sg
183	* into the locally allocated *buf
184	*/
185	sg_copy_to_buffer(cmd->t_data_sg,
186	cmd->t_data_nents,
187	buf,
188	cmd->data_length);
189
190	/*
191	* Now perform the XOR against the BIDI read memory located at
192	* cmd->t_mem_bidi_list
193	*/
194
195	offset = 0;
196	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
197	addr = kmap_atomic(sg_page(sg));
198	if (!addr)
199	goto out;
200
201	for (i = 0; i < sg->length; i++)
202	(addr + sg->offset + i) ^= (buf + offset + i);
203
204	offset += sg->length;
205	kunmap_atomic(addr);
206	}
207
208	out:
209	kfree(buf);
210	}
211
212	int sbc_parse_cdb(struct se_cmd cmd, unsigned int size)
213	{
214	struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
215	struct se_device *dev = cmd->se_dev;
216	unsigned char *cdb = cmd->t_task_cdb;
217	u32 sectors = 0;
218	int ret;
219
220	switch (cdb[0]) {
221	case READ_6:
222	sectors = transport_get_sectors_6(cdb);
223	cmd->t_task_lba = transport_lba_21(cdb);
224	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
225	break;
226	case READ_10:
227	sectors = transport_get_sectors_10(cdb);
228	cmd->t_task_lba = transport_lba_32(cdb);
229	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
230	break;
231	case READ_12:
232	sectors = transport_get_sectors_12(cdb);
233	cmd->t_task_lba = transport_lba_32(cdb);
234	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
235	break;
236	case READ_16:
237	sectors = transport_get_sectors_16(cdb);
238	cmd->t_task_lba = transport_lba_64(cdb);
239	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
240	break;
241	case WRITE_6:
242	sectors = transport_get_sectors_6(cdb);
243	cmd->t_task_lba = transport_lba_21(cdb);
244	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
245	break;
246	case WRITE_10:
247	case WRITE_VERIFY:
248	sectors = transport_get_sectors_10(cdb);
249	cmd->t_task_lba = transport_lba_32(cdb);
250	if (cdb[1] & 0x8)
251	cmd->se_cmd_flags \|= SCF_FUA;
252	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
253	break;
254	case WRITE_12:
255	sectors = transport_get_sectors_12(cdb);
256	cmd->t_task_lba = transport_lba_32(cdb);
257	if (cdb[1] & 0x8)
258	cmd->se_cmd_flags \|= SCF_FUA;
259	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
260	break;
261	case WRITE_16:
262	sectors = transport_get_sectors_16(cdb);
263	cmd->t_task_lba = transport_lba_64(cdb);
264	if (cdb[1] & 0x8)
265	cmd->se_cmd_flags \|= SCF_FUA;
266	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
267	break;
268	case XDWRITEREAD_10:
269	if ((cmd->data_direction != DMA_TO_DEVICE) \|\|
270	!(cmd->se_cmd_flags & SCF_BIDI))
271	goto out_invalid_cdb_field;
272	sectors = transport_get_sectors_10(cdb);
273
274	cmd->t_task_lba = transport_lba_32(cdb);
275	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
276
277	/*
278	* Setup BIDI XOR callback to be run after I/O completion.
279	*/
280	cmd->transport_complete_callback = &xdreadwrite_callback;
281	if (cdb[1] & 0x8)
282	cmd->se_cmd_flags \|= SCF_FUA;
283	break;
284	case VARIABLE_LENGTH_CMD:
285	{
286	u16 service_action = get_unaligned_be16(&cdb[8]);
287	switch (service_action) {
288	case XDWRITEREAD_32:
289	sectors = transport_get_sectors_32(cdb);
290
291	/*
292	* Use WRITE_32 and READ_32 opcodes for the emulated
293	* XDWRITE_READ_32 logic.
294	*/
295	cmd->t_task_lba = transport_lba_64_ext(cdb);
296	cmd->se_cmd_flags \|= SCF_SCSI_DATA_CDB;
297
298	/*
299	* Setup BIDI XOR callback to be run during after I/O
300	* completion.
301	*/
302	cmd->transport_complete_callback = &xdreadwrite_callback;
303	if (cdb[1] & 0x8)
304	cmd->se_cmd_flags \|= SCF_FUA;
305	break;
306	case WRITE_SAME_32:
307	sectors = transport_get_sectors_32(cdb);
308	if (!sectors) {
309	pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
310	" supported\n");
311	goto out_invalid_cdb_field;
312	}
313
314	*size = sbc_get_size(cmd, 1);
315	cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
316
317	if (sbc_write_same_supported(dev, &cdb[10]) < 0)
318	goto out_unsupported_cdb;
319	cmd->execute_cmd = target_emulate_write_same;
320	break;
321	default:
322	pr_err("VARIABLE_LENGTH_CMD service action"
323	" 0x%04x not supported\n", service_action);
324	goto out_unsupported_cdb;
325	}
326	break;
327	}
328	case READ_CAPACITY:
329	*size = READ_CAP_LEN;
330	cmd->execute_cmd = target_emulate_readcapacity;
331	break;
332	case SERVICE_ACTION_IN:
333	switch (cmd->t_task_cdb[1] & 0x1f) {
334	case SAI_READ_CAPACITY_16:
335	cmd->execute_cmd = target_emulate_readcapacity_16;
336	break;
337	default:
338	pr_err("Unsupported SA: 0x%02x\n",
339	cmd->t_task_cdb[1] & 0x1f);
340	goto out_invalid_cdb_field;
341	}
342	*size = (cdb[10] << 24) \| (cdb[11] << 16) \|
343	(cdb[12] << 8) \| cdb[13];
344	break;
345	case SYNCHRONIZE_CACHE:
346	case SYNCHRONIZE_CACHE_16:
347	/*
348	* Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
349	*/
350	if (cdb[0] == SYNCHRONIZE_CACHE) {
351	sectors = transport_get_sectors_10(cdb);
352	cmd->t_task_lba = transport_lba_32(cdb);
353	} else {
354	sectors = transport_get_sectors_16(cdb);
355	cmd->t_task_lba = transport_lba_64(cdb);
356	}
357
358	*size = sbc_get_size(cmd, sectors);
359
360	/*
361	* Check to ensure that LBA + Range does not exceed past end of
362	* device for IBLOCK and FILEIO ->do_sync_cache() backend calls
363	*/
364	if (cmd->t_task_lba \|\| sectors) {
365	if (sbc_check_valid_sectors(cmd) < 0)
366	goto out_invalid_cdb_field;
367	}
368	cmd->execute_cmd = target_emulate_synchronize_cache;
369	break;
370	case UNMAP:
371	*size = get_unaligned_be16(&cdb[7]);
372	cmd->execute_cmd = target_emulate_unmap;
373	break;
374	case WRITE_SAME_16:
375	sectors = transport_get_sectors_16(cdb);
376	if (!sectors) {
377	pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
378	goto out_invalid_cdb_field;
379	}
380
381	*size = sbc_get_size(cmd, 1);
382	cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
383
384	if (sbc_write_same_supported(dev, &cdb[1]) < 0)
385	goto out_unsupported_cdb;
386	cmd->execute_cmd = target_emulate_write_same;
387	break;
388	case WRITE_SAME:
389	sectors = transport_get_sectors_10(cdb);
390	if (!sectors) {
391	pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
392	goto out_invalid_cdb_field;
393	}
394
395	*size = sbc_get_size(cmd, 1);
396	cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
397
398	/*
399	* Follow sbcr26 with WRITE_SAME (10) and check for the existence
400	* of byte 1 bit 3 UNMAP instead of original reserved field
401	*/
402	if (sbc_write_same_supported(dev, &cdb[1]) < 0)
403	goto out_unsupported_cdb;
404	cmd->execute_cmd = target_emulate_write_same;
405	break;
406	case VERIFY:
407	*size = 0;
408	cmd->execute_cmd = target_emulate_noop;
409	break;
410	default:
411	ret = spc_parse_cdb(cmd, size, false);
412	if (ret)
413	return ret;
414	}
415
416	/* reject any command that we don't have a handler for */
417	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
418	goto out_unsupported_cdb;
419
420	if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
421	if (sectors > su_dev->se_dev_attrib.fabric_max_sectors) {
422	printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
423	" big sectors %u exceeds fabric_max_sectors:"
424	" %u\n", cdb[0], sectors,
425	su_dev->se_dev_attrib.fabric_max_sectors);
426	goto out_invalid_cdb_field;
427	}
428	if (sectors > su_dev->se_dev_attrib.hw_max_sectors) {
429	printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
430	" big sectors %u exceeds backend hw_max_sectors:"
431	" %u\n", cdb[0], sectors,
432	su_dev->se_dev_attrib.hw_max_sectors);
433	goto out_invalid_cdb_field;
434	}
435
436	*size = sbc_get_size(cmd, sectors);
437	}
438
439	return 0;
440
441	out_unsupported_cdb:
442	cmd->se_cmd_flags \|= SCF_SCSI_CDB_EXCEPTION;
443	cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
444	return -EINVAL;
445	out_invalid_cdb_field:
446	cmd->se_cmd_flags \|= SCF_SCSI_CDB_EXCEPTION;
447	cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
448	return -EINVAL;
449	}
450	EXPORT_SYMBOL(sbc_parse_cdb);