// SPDX-License-Identifier: GPL-2.0-or-later /* * SCSI Block Commands (SBC) parsing and emulation. * * (c) Copyright 2002-2013 Datera, Inc. * * Nicholas A. Bellinger */ #include #include #include #include #include #include #include #include #include #include #include #include "target_core_internal.h" #include "target_core_ua.h" #include "target_core_alua.h" static sense_reason_t sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char, u32, bool); static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd); static sense_reason_t sbc_emulate_readcapacity(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; unsigned char *cdb = cmd->t_task_cdb; unsigned long long blocks_long = dev->transport->get_blocks(dev); unsigned char *rbuf; unsigned char buf[8]; u32 blocks; /* * SBC-2 says: * If the PMI bit is set to zero and the LOGICAL BLOCK * ADDRESS field is not set to zero, the device server shall * terminate the command with CHECK CONDITION status with * the sense key set to ILLEGAL REQUEST and the additional * sense code set to INVALID FIELD IN CDB. * * In SBC-3, these fields are obsolete, but some SCSI * compliance tests actually check this, so we might as well * follow SBC-2. */ if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5])) return TCM_INVALID_CDB_FIELD; if (blocks_long >= 0x00000000ffffffff) blocks = 0xffffffff; else blocks = (u32)blocks_long; put_unaligned_be32(blocks, &buf[0]); put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]); rbuf = transport_kmap_data_sg(cmd); if (rbuf) { memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); transport_kunmap_data_sg(cmd); } target_complete_cmd_with_length(cmd, GOOD, 8); return 0; } static sense_reason_t sbc_emulate_readcapacity_16(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct se_session *sess = cmd->se_sess; int pi_prot_type = dev->dev_attrib.pi_prot_type; unsigned char *rbuf; unsigned char buf[32]; unsigned long long blocks = dev->transport->get_blocks(dev); memset(buf, 0, sizeof(buf)); put_unaligned_be64(blocks, &buf[0]); put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]); /* * Set P_TYPE and PROT_EN bits for DIF support */ if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) { /* * Only override a device's pi_prot_type if no T10-PI is * available, and sess_prot_type has been explicitly enabled. */ if (!pi_prot_type) pi_prot_type = sess->sess_prot_type; if (pi_prot_type) buf[12] = (pi_prot_type - 1) << 1 | 0x1; } if (dev->transport->get_lbppbe) buf[13] = dev->transport->get_lbppbe(dev) & 0x0f; if (dev->transport->get_alignment_offset_lbas) { u16 lalba = dev->transport->get_alignment_offset_lbas(dev); put_unaligned_be16(lalba, &buf[14]); } /* * Set Thin Provisioning Enable bit following sbc3r22 in section * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled. */ if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) { buf[14] |= 0x80; /* * LBPRZ signifies that zeroes will be read back from an LBA after * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2) */ if (dev->dev_attrib.unmap_zeroes_data) buf[14] |= 0x40; } rbuf = transport_kmap_data_sg(cmd); if (rbuf) { memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length)); transport_kunmap_data_sg(cmd); } target_complete_cmd_with_length(cmd, GOOD, 32); return 0; } static sense_reason_t sbc_emulate_startstop(struct se_cmd *cmd) { unsigned char *cdb = cmd->t_task_cdb; /* * See sbc3r36 section 5.25 * Immediate bit should be set since there is nothing to complete * POWER CONDITION MODIFIER 0h */ if (!(cdb[1] & 1) || cdb[2] || cdb[3]) return TCM_INVALID_CDB_FIELD; /* * See sbc3r36 section 5.25 * POWER CONDITION 0h START_VALID - process START and LOEJ */ if (cdb[4] >> 4 & 0xf) return TCM_INVALID_CDB_FIELD; /* * See sbc3r36 section 5.25 * LOEJ 0h - nothing to load or unload * START 1h - we are ready */ if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4)) return TCM_INVALID_CDB_FIELD; target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } sector_t sbc_get_write_same_sectors(struct se_cmd *cmd) { u32 num_blocks; if (cmd->t_task_cdb[0] == WRITE_SAME) num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]); else if (cmd->t_task_cdb[0] == WRITE_SAME_16) num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]); else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */ num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]); /* * Use the explicit range when non zero is supplied, otherwise calculate * the remaining range based on ->get_blocks() - starting LBA. */ if (num_blocks) return num_blocks; return cmd->se_dev->transport->get_blocks(cmd->se_dev) - cmd->t_task_lba + 1; } EXPORT_SYMBOL(sbc_get_write_same_sectors); static sense_reason_t sbc_execute_write_same_unmap(struct se_cmd *cmd) { struct sbc_ops *ops = cmd->protocol_data; sector_t nolb = sbc_get_write_same_sectors(cmd); sense_reason_t ret; if (nolb) { ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb); if (ret) return ret; } target_complete_cmd(cmd, GOOD); return 0; } static sense_reason_t sbc_emulate_noop(struct se_cmd *cmd) { target_complete_cmd(cmd, GOOD); return 0; } static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors) { return cmd->se_dev->dev_attrib.block_size * sectors; } 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 get_unaligned_be16(&cdb[7]); } static inline u32 transport_get_sectors_12(unsigned char *cdb) { return get_unaligned_be32(&cdb[6]); } static inline u32 transport_get_sectors_16(unsigned char *cdb) { return get_unaligned_be32(&cdb[10]); } /* * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants */ static inline u32 transport_get_sectors_32(unsigned char *cdb) { return get_unaligned_be32(&cdb[28]); } static inline u32 transport_lba_21(unsigned char *cdb) { return get_unaligned_be24(&cdb[1]) & 0x1fffff; } static inline u32 transport_lba_32(unsigned char *cdb) { return get_unaligned_be32(&cdb[2]); } static inline unsigned long long transport_lba_64(unsigned char *cdb) { return get_unaligned_be64(&cdb[2]); } /* * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs */ static inline unsigned long long transport_lba_64_ext(unsigned char *cdb) { return get_unaligned_be64(&cdb[12]); } static sense_reason_t sbc_setup_write_same(struct se_cmd *cmd, unsigned char flags, struct sbc_ops *ops) { struct se_device *dev = cmd->se_dev; sector_t end_lba = dev->transport->get_blocks(dev) + 1; unsigned int sectors = sbc_get_write_same_sectors(cmd); sense_reason_t ret; if ((flags & 0x04) || (flags & 0x02)) { pr_err("WRITE_SAME PBDATA and LBDATA" " bits not supported for Block Discard" " Emulation\n"); return TCM_UNSUPPORTED_SCSI_OPCODE; } if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) { pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n", sectors, cmd->se_dev->dev_attrib.max_write_same_len); return TCM_INVALID_CDB_FIELD; } /* * Sanity check for LBA wrap and request past end of device. */ if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || ((cmd->t_task_lba + sectors) > end_lba)) { pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n", (unsigned long long)end_lba, cmd->t_task_lba, sectors); return TCM_ADDRESS_OUT_OF_RANGE; } /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */ if (flags & 0x10) { pr_warn("WRITE SAME with ANCHOR not supported\n"); return TCM_INVALID_CDB_FIELD; } /* * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting * translated into block discard requests within backend code. */ if (flags & 0x08) { if (!ops->execute_unmap) return TCM_UNSUPPORTED_SCSI_OPCODE; if (!dev->dev_attrib.emulate_tpws) { pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device" " has emulate_tpws disabled\n"); return TCM_UNSUPPORTED_SCSI_OPCODE; } cmd->execute_cmd = sbc_execute_write_same_unmap; return 0; } if (!ops->execute_write_same) return TCM_UNSUPPORTED_SCSI_OPCODE; ret = sbc_check_prot(dev, cmd, flags >> 5, sectors, true); if (ret) return ret; cmd->execute_cmd = ops->execute_write_same; return 0; } static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success, int *post_ret) { unsigned char *buf, *addr; struct scatterlist *sg; unsigned int offset; sense_reason_t ret = TCM_NO_SENSE; int i, count; if (!success) return 0; /* * 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 TCM_OUT_OF_RESOURCES; } /* * 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) { ret = TCM_OUT_OF_RESOURCES; 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); return ret; } static sense_reason_t sbc_execute_rw(struct se_cmd *cmd) { struct sbc_ops *ops = cmd->protocol_data; return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents, cmd->data_direction); } static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success, int *post_ret) { struct se_device *dev = cmd->se_dev; sense_reason_t ret = TCM_NO_SENSE; spin_lock_irq(&cmd->t_state_lock); if (success) { *post_ret = 1; if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } spin_unlock_irq(&cmd->t_state_lock); /* * Unlock ->caw_sem originally obtained during sbc_compare_and_write() * before the original READ I/O submission. */ up(&dev->caw_sem); return ret; } static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success, int *post_ret) { struct se_device *dev = cmd->se_dev; struct sg_table write_tbl = { }; struct scatterlist *write_sg, *sg; unsigned char *buf = NULL, *addr; struct sg_mapping_iter m; unsigned int offset = 0, len; unsigned int nlbas = cmd->t_task_nolb; unsigned int block_size = dev->dev_attrib.block_size; unsigned int compare_len = (nlbas * block_size); sense_reason_t ret = TCM_NO_SENSE; int rc, i; /* * Handle early failure in transport_generic_request_failure(), * which will not have taken ->caw_sem yet.. */ if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg)) return TCM_NO_SENSE; /* * Handle special case for zero-length COMPARE_AND_WRITE */ if (!cmd->data_length) goto out; /* * Immediately exit + release dev->caw_sem if command has already * been failed with a non-zero SCSI status. */ if (cmd->scsi_status) { pr_debug("compare_and_write_callback: non zero scsi_status:" " 0x%02x\n", cmd->scsi_status); *post_ret = 1; if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION) ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; goto out; } buf = kzalloc(cmd->data_length, GFP_KERNEL); if (!buf) { pr_err("Unable to allocate compare_and_write buf\n"); ret = TCM_OUT_OF_RESOURCES; goto out; } if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) { pr_err("Unable to allocate compare_and_write sg\n"); ret = TCM_OUT_OF_RESOURCES; goto out; } write_sg = write_tbl.sgl; /* * Setup verify and write data payloads from total NumberLBAs. */ rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf, cmd->data_length); if (!rc) { pr_err("sg_copy_to_buffer() failed for compare_and_write\n"); ret = TCM_OUT_OF_RESOURCES; goto out; } /* * Compare against SCSI READ payload against verify payload */ for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) { addr = (unsigned char *)kmap_atomic(sg_page(sg)); if (!addr) { ret = TCM_OUT_OF_RESOURCES; goto out; } len = min(sg->length, compare_len); if (memcmp(addr, buf + offset, len)) { pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n", addr, buf + offset); kunmap_atomic(addr); goto miscompare; } kunmap_atomic(addr); offset += len; compare_len -= len; if (!compare_len) break; } i = 0; len = cmd->t_task_nolb * block_size; sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG); /* * Currently assumes NoLB=1 and SGLs are PAGE_SIZE.. */ while (len) { sg_miter_next(&m); if (block_size < PAGE_SIZE) { sg_set_page(&write_sg[i], m.page, block_size, m.piter.sg->offset + block_size); } else { sg_miter_next(&m); sg_set_page(&write_sg[i], m.page, block_size, m.piter.sg->offset); } len -= block_size; i++; } sg_miter_stop(&m); /* * Save the original SGL + nents values before updating to new * assignments, to be released in transport_free_pages() -> * transport_reset_sgl_orig() */ cmd->t_data_sg_orig = cmd->t_data_sg; cmd->t_data_sg = write_sg; cmd->t_data_nents_orig = cmd->t_data_nents; cmd->t_data_nents = 1; cmd->sam_task_attr = TCM_HEAD_TAG; cmd->transport_complete_callback = compare_and_write_post; /* * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler * for submitting the adjusted SGL to write instance user-data. */ cmd->execute_cmd = sbc_execute_rw; spin_lock_irq(&cmd->t_state_lock); cmd->t_state = TRANSPORT_PROCESSING; cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; spin_unlock_irq(&cmd->t_state_lock); __target_execute_cmd(cmd, false); kfree(buf); return ret; miscompare: pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n", dev->transport->name); ret = TCM_MISCOMPARE_VERIFY; out: /* * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in * sbc_compare_and_write() before the original READ I/O submission. */ up(&dev->caw_sem); sg_free_table(&write_tbl); kfree(buf); return ret; } static sense_reason_t sbc_compare_and_write(struct se_cmd *cmd) { struct sbc_ops *ops = cmd->protocol_data; struct se_device *dev = cmd->se_dev; sense_reason_t ret; int rc; /* * Submit the READ first for COMPARE_AND_WRITE to perform the * comparision using SGLs at cmd->t_bidi_data_sg.. */ rc = down_interruptible(&dev->caw_sem); if (rc != 0) { cmd->transport_complete_callback = NULL; return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } /* * Reset cmd->data_length to individual block_size in order to not * confuse backend drivers that depend on this value matching the * size of the I/O being submitted. */ cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, DMA_FROM_DEVICE); if (ret) { cmd->transport_complete_callback = NULL; up(&dev->caw_sem); return ret; } /* * Unlock of dev->caw_sem to occur in compare_and_write_callback() * upon MISCOMPARE, or in compare_and_write_done() upon completion * of WRITE instance user-data. */ return TCM_NO_SENSE; } static int sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type, bool is_write, struct se_cmd *cmd) { if (is_write) { cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP : protect ? TARGET_PROT_DOUT_PASS : TARGET_PROT_DOUT_INSERT; switch (protect) { case 0x0: case 0x3: cmd->prot_checks = 0; break; case 0x1: case 0x5: cmd->prot_checks = TARGET_DIF_CHECK_GUARD; if (prot_type == TARGET_DIF_TYPE1_PROT) cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; break; case 0x2: if (prot_type == TARGET_DIF_TYPE1_PROT) cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; break; case 0x4: cmd->prot_checks = TARGET_DIF_CHECK_GUARD; break; default: pr_err("Unsupported protect field %d\n", protect); return -EINVAL; } } else { cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT : protect ? TARGET_PROT_DIN_PASS : TARGET_PROT_DIN_STRIP; switch (protect) { case 0x0: case 0x1: case 0x5: cmd->prot_checks = TARGET_DIF_CHECK_GUARD; if (prot_type == TARGET_DIF_TYPE1_PROT) cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG; break; case 0x2: if (prot_type == TARGET_DIF_TYPE1_PROT) cmd->prot_checks = TARGET_DIF_CHECK_REFTAG; break; case 0x3: cmd->prot_checks = 0; break; case 0x4: cmd->prot_checks = TARGET_DIF_CHECK_GUARD; break; default: pr_err("Unsupported protect field %d\n", protect); return -EINVAL; } } return 0; } static sense_reason_t sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect, u32 sectors, bool is_write) { int sp_ops = cmd->se_sess->sup_prot_ops; int pi_prot_type = dev->dev_attrib.pi_prot_type; bool fabric_prot = false; if (!cmd->t_prot_sg || !cmd->t_prot_nents) { if (unlikely(protect && !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) { pr_err("CDB contains protect bit, but device + fabric does" " not advertise PROTECT=1 feature bit\n"); return TCM_INVALID_CDB_FIELD; } if (cmd->prot_pto) return TCM_NO_SENSE; } switch (dev->dev_attrib.pi_prot_type) { case TARGET_DIF_TYPE3_PROT: cmd->reftag_seed = 0xffffffff; break; case TARGET_DIF_TYPE2_PROT: if (protect) return TCM_INVALID_CDB_FIELD; cmd->reftag_seed = cmd->t_task_lba; break; case TARGET_DIF_TYPE1_PROT: cmd->reftag_seed = cmd->t_task_lba; break; case TARGET_DIF_TYPE0_PROT: /* * See if the fabric supports T10-PI, and the session has been * configured to allow export PROTECT=1 feature bit with backend * devices that don't support T10-PI. */ fabric_prot = is_write ? !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) : !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT)); if (fabric_prot && cmd->se_sess->sess_prot_type) { pi_prot_type = cmd->se_sess->sess_prot_type; break; } if (!protect) return TCM_NO_SENSE; fallthrough; default: pr_err("Unable to determine pi_prot_type for CDB: 0x%02x " "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect); return TCM_INVALID_CDB_FIELD; } if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd)) return TCM_INVALID_CDB_FIELD; cmd->prot_type = pi_prot_type; cmd->prot_length = dev->prot_length * sectors; /** * In case protection information exists over the wire * we modify command data length to describe pure data. * The actual transfer length is data length + protection * length **/ if (protect) cmd->data_length = sectors * dev->dev_attrib.block_size; pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d " "prot_op=%d prot_checks=%d\n", __func__, cmd->prot_type, cmd->data_length, cmd->prot_length, cmd->prot_op, cmd->prot_checks); return TCM_NO_SENSE; } static int sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb) { if (cdb[1] & 0x10) { /* see explanation in spc_emulate_modesense */ if (!target_check_fua(dev)) { pr_err("Got CDB: 0x%02x with DPO bit set, but device" " does not advertise support for DPO\n", cdb[0]); return -EINVAL; } } if (cdb[1] & 0x8) { if (!target_check_fua(dev)) { pr_err("Got CDB: 0x%02x with FUA bit set, but device" " does not advertise support for FUA write\n", cdb[0]); return -EINVAL; } cmd->se_cmd_flags |= SCF_FUA; } return 0; } sense_reason_t sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) { struct se_device *dev = cmd->se_dev; unsigned char *cdb = cmd->t_task_cdb; unsigned int size; u32 sectors = 0; sense_reason_t ret; cmd->protocol_data = ops; 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; cmd->execute_cmd = sbc_execute_rw; break; case READ_10: sectors = transport_get_sectors_10(cdb); cmd->t_task_lba = transport_lba_32(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; case READ_12: sectors = transport_get_sectors_12(cdb); cmd->t_task_lba = transport_lba_32(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; case READ_16: sectors = transport_get_sectors_16(cdb); cmd->t_task_lba = transport_lba_64(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; 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; cmd->execute_cmd = sbc_execute_rw; break; case WRITE_10: case WRITE_VERIFY: sectors = transport_get_sectors_10(cdb); cmd->t_task_lba = transport_lba_32(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; case WRITE_12: sectors = transport_get_sectors_12(cdb); cmd->t_task_lba = transport_lba_32(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; case WRITE_16: case WRITE_VERIFY_16: sectors = transport_get_sectors_16(cdb); cmd->t_task_lba = transport_lba_64(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true); if (ret) return ret; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; case XDWRITEREAD_10: if (cmd->data_direction != DMA_TO_DEVICE || !(cmd->se_cmd_flags & SCF_BIDI)) return TCM_INVALID_CDB_FIELD; sectors = transport_get_sectors_10(cdb); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; 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->execute_cmd = sbc_execute_rw; cmd->transport_complete_callback = &xdreadwrite_callback; 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); if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; /* * 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->execute_cmd = sbc_execute_rw; cmd->transport_complete_callback = &xdreadwrite_callback; 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"); return TCM_INVALID_CDB_FIELD; } size = sbc_get_size(cmd, 1); cmd->t_task_lba = get_unaligned_be64(&cdb[12]); ret = sbc_setup_write_same(cmd, cdb[10], ops); if (ret) return ret; break; default: pr_err("VARIABLE_LENGTH_CMD service action" " 0x%04x not supported\n", service_action); return TCM_UNSUPPORTED_SCSI_OPCODE; } break; } case COMPARE_AND_WRITE: if (!dev->dev_attrib.emulate_caw) { pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n", dev->se_hba->backend->ops->name, config_item_name(&dev->dev_group.cg_item), dev->t10_wwn.unit_serial); return TCM_UNSUPPORTED_SCSI_OPCODE; } sectors = cdb[13]; /* * Currently enforce COMPARE_AND_WRITE for a single sector */ if (sectors > 1) { pr_err("COMPARE_AND_WRITE contains NoLB: %u greater" " than 1\n", sectors); return TCM_INVALID_CDB_FIELD; } if (sbc_check_dpofua(dev, cmd, cdb)) return TCM_INVALID_CDB_FIELD; /* * Double size because we have two buffers, note that * zero is not an error.. */ size = 2 * sbc_get_size(cmd, sectors); cmd->t_task_lba = get_unaligned_be64(&cdb[2]); cmd->t_task_nolb = sectors; cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE; cmd->execute_cmd = sbc_compare_and_write; cmd->transport_complete_callback = compare_and_write_callback; break; case READ_CAPACITY: size = READ_CAP_LEN; cmd->execute_cmd = sbc_emulate_readcapacity; break; case SERVICE_ACTION_IN_16: switch (cmd->t_task_cdb[1] & 0x1f) { case SAI_READ_CAPACITY_16: cmd->execute_cmd = sbc_emulate_readcapacity_16; break; case SAI_REPORT_REFERRALS: cmd->execute_cmd = target_emulate_report_referrals; break; default: pr_err("Unsupported SA: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f); return TCM_INVALID_CDB_FIELD; } size = get_unaligned_be32(&cdb[10]); break; case SYNCHRONIZE_CACHE: case SYNCHRONIZE_CACHE_16: 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); } if (ops->execute_sync_cache) { cmd->execute_cmd = ops->execute_sync_cache; goto check_lba; } size = 0; cmd->execute_cmd = sbc_emulate_noop; break; case UNMAP: if (!ops->execute_unmap) return TCM_UNSUPPORTED_SCSI_OPCODE; if (!dev->dev_attrib.emulate_tpu) { pr_err("Got UNMAP, but backend device has" " emulate_tpu disabled\n"); return TCM_UNSUPPORTED_SCSI_OPCODE; } size = get_unaligned_be16(&cdb[7]); cmd->execute_cmd = sbc_execute_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"); return TCM_INVALID_CDB_FIELD; } size = sbc_get_size(cmd, 1); cmd->t_task_lba = get_unaligned_be64(&cdb[2]); ret = sbc_setup_write_same(cmd, cdb[1], ops); if (ret) return ret; break; case WRITE_SAME: sectors = transport_get_sectors_10(cdb); if (!sectors) { pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); return TCM_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 */ ret = sbc_setup_write_same(cmd, cdb[1], ops); if (ret) return ret; break; case VERIFY: case VERIFY_16: size = 0; if (cdb[0] == VERIFY) { 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); } cmd->execute_cmd = sbc_emulate_noop; goto check_lba; case REZERO_UNIT: case SEEK_6: case SEEK_10: /* * There are still clients out there which use these old SCSI-2 * commands. This mainly happens when running VMs with legacy * guest systems, connected via SCSI command pass-through to * iSCSI targets. Make them happy and return status GOOD. */ size = 0; cmd->execute_cmd = sbc_emulate_noop; break; case START_STOP: size = 0; cmd->execute_cmd = sbc_emulate_startstop; break; default: ret = spc_parse_cdb(cmd, &size); if (ret) return ret; } /* reject any command that we don't have a handler for */ if (!cmd->execute_cmd) return TCM_UNSUPPORTED_SCSI_OPCODE; if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { unsigned long long end_lba; check_lba: end_lba = dev->transport->get_blocks(dev) + 1; if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) || ((cmd->t_task_lba + sectors) > end_lba)) { pr_err("cmd exceeds last lba %llu " "(lba %llu, sectors %u)\n", end_lba, cmd->t_task_lba, sectors); return TCM_ADDRESS_OUT_OF_RANGE; } if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) size = sbc_get_size(cmd, sectors); } return target_cmd_size_check(cmd, size); } EXPORT_SYMBOL(sbc_parse_cdb); u32 sbc_get_device_type(struct se_device *dev) { return TYPE_DISK; } EXPORT_SYMBOL(sbc_get_device_type); static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd) { struct sbc_ops *ops = cmd->protocol_data; struct se_device *dev = cmd->se_dev; unsigned char *buf, *ptr = NULL; sector_t lba; int size; u32 range; sense_reason_t ret = 0; int dl, bd_dl; /* We never set ANC_SUP */ if (cmd->t_task_cdb[1]) return TCM_INVALID_CDB_FIELD; if (cmd->data_length == 0) { target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; } if (cmd->data_length < 8) { pr_warn("UNMAP parameter list length %u too small\n", cmd->data_length); return TCM_PARAMETER_LIST_LENGTH_ERROR; } buf = transport_kmap_data_sg(cmd); if (!buf) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; dl = get_unaligned_be16(&buf[0]); bd_dl = get_unaligned_be16(&buf[2]); size = cmd->data_length - 8; if (bd_dl > size) pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n", cmd->data_length, bd_dl); else size = bd_dl; if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) { ret = TCM_INVALID_PARAMETER_LIST; goto err; } /* First UNMAP block descriptor starts at 8 byte offset */ ptr = &buf[8]; pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u" " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr); while (size >= 16) { lba = get_unaligned_be64(&ptr[0]); range = get_unaligned_be32(&ptr[8]); pr_debug("UNMAP: Using lba: %llu and range: %u\n", (unsigned long long)lba, range); if (range > dev->dev_attrib.max_unmap_lba_count) { ret = TCM_INVALID_PARAMETER_LIST; goto err; } if (lba + range > dev->transport->get_blocks(dev) + 1) { ret = TCM_ADDRESS_OUT_OF_RANGE; goto err; } if (range) { ret = ops->execute_unmap(cmd, lba, range); if (ret) goto err; } ptr += 16; size -= 16; } err: transport_kunmap_data_sg(cmd); if (!ret) target_complete_cmd(cmd, GOOD); return ret; } void sbc_dif_generate(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct t10_pi_tuple *sdt; struct scatterlist *dsg = cmd->t_data_sg, *psg; sector_t sector = cmd->t_task_lba; void *daddr, *paddr; int i, j, offset = 0; unsigned int block_size = dev->dev_attrib.block_size; for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { paddr = kmap_atomic(sg_page(psg)) + psg->offset; daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; for (j = 0; j < psg->length; j += sizeof(*sdt)) { __u16 crc; unsigned int avail; if (offset >= dsg->length) { offset -= dsg->length; kunmap_atomic(daddr - dsg->offset); dsg = sg_next(dsg); if (!dsg) { kunmap_atomic(paddr - psg->offset); return; } daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; } sdt = paddr + j; avail = min(block_size, dsg->length - offset); crc = crc_t10dif(daddr + offset, avail); if (avail < block_size) { kunmap_atomic(daddr - dsg->offset); dsg = sg_next(dsg); if (!dsg) { kunmap_atomic(paddr - psg->offset); return; } daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; offset = block_size - avail; crc = crc_t10dif_update(crc, daddr, offset); } else { offset += block_size; } sdt->guard_tag = cpu_to_be16(crc); if (cmd->prot_type == TARGET_DIF_TYPE1_PROT) sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); sdt->app_tag = 0; pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x" " app_tag: 0x%04x ref_tag: %u\n", (cmd->data_direction == DMA_TO_DEVICE) ? "WRITE" : "READ", (unsigned long long)sector, sdt->guard_tag, sdt->app_tag, be32_to_cpu(sdt->ref_tag)); sector++; } kunmap_atomic(daddr - dsg->offset); kunmap_atomic(paddr - psg->offset); } } static sense_reason_t sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt, __u16 crc, sector_t sector, unsigned int ei_lba) { __be16 csum; if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD)) goto check_ref; csum = cpu_to_be16(crc); if (sdt->guard_tag != csum) { pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x" " csum 0x%04x\n", (unsigned long long)sector, be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED; } check_ref: if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)) return 0; if (cmd->prot_type == TARGET_DIF_TYPE1_PROT && be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) { pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x" " sector MSB: 0x%08x\n", (unsigned long long)sector, be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff)); return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; } if (cmd->prot_type == TARGET_DIF_TYPE2_PROT && be32_to_cpu(sdt->ref_tag) != ei_lba) { pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x" " ei_lba: 0x%08x\n", (unsigned long long)sector, be32_to_cpu(sdt->ref_tag), ei_lba); return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED; } return 0; } void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read, struct scatterlist *sg, int sg_off) { struct se_device *dev = cmd->se_dev; struct scatterlist *psg; void *paddr, *addr; unsigned int i, len, left; unsigned int offset = sg_off; if (!sg) return; left = sectors * dev->prot_length; for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) { unsigned int psg_len, copied = 0; paddr = kmap_atomic(sg_page(psg)) + psg->offset; psg_len = min(left, psg->length); while (psg_len) { len = min(psg_len, sg->length - offset); addr = kmap_atomic(sg_page(sg)) + sg->offset + offset; if (read) memcpy(paddr + copied, addr, len); else memcpy(addr, paddr + copied, len); left -= len; offset += len; copied += len; psg_len -= len; kunmap_atomic(addr - sg->offset - offset); if (offset >= sg->length) { sg = sg_next(sg); offset = 0; } } kunmap_atomic(paddr - psg->offset); } } EXPORT_SYMBOL(sbc_dif_copy_prot); sense_reason_t sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors, unsigned int ei_lba, struct scatterlist *psg, int psg_off) { struct se_device *dev = cmd->se_dev; struct t10_pi_tuple *sdt; struct scatterlist *dsg = cmd->t_data_sg; sector_t sector = start; void *daddr, *paddr; int i; sense_reason_t rc; int dsg_off = 0; unsigned int block_size = dev->dev_attrib.block_size; for (; psg && sector < start + sectors; psg = sg_next(psg)) { paddr = kmap_atomic(sg_page(psg)) + psg->offset; daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; for (i = psg_off; i < psg->length && sector < start + sectors; i += sizeof(*sdt)) { __u16 crc; unsigned int avail; if (dsg_off >= dsg->length) { dsg_off -= dsg->length; kunmap_atomic(daddr - dsg->offset); dsg = sg_next(dsg); if (!dsg) { kunmap_atomic(paddr - psg->offset); return 0; } daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; } sdt = paddr + i; pr_debug("DIF READ sector: %llu guard_tag: 0x%04x" " app_tag: 0x%04x ref_tag: %u\n", (unsigned long long)sector, sdt->guard_tag, sdt->app_tag, be32_to_cpu(sdt->ref_tag)); if (sdt->app_tag == T10_PI_APP_ESCAPE) { dsg_off += block_size; goto next; } avail = min(block_size, dsg->length - dsg_off); crc = crc_t10dif(daddr + dsg_off, avail); if (avail < block_size) { kunmap_atomic(daddr - dsg->offset); dsg = sg_next(dsg); if (!dsg) { kunmap_atomic(paddr - psg->offset); return 0; } daddr = kmap_atomic(sg_page(dsg)) + dsg->offset; dsg_off = block_size - avail; crc = crc_t10dif_update(crc, daddr, dsg_off); } else { dsg_off += block_size; } rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba); if (rc) { kunmap_atomic(daddr - dsg->offset); kunmap_atomic(paddr - psg->offset); cmd->sense_info = sector; return rc; } next: sector++; ei_lba++; } psg_off = 0; kunmap_atomic(daddr - dsg->offset); kunmap_atomic(paddr - psg->offset); } return 0; } EXPORT_SYMBOL(sbc_dif_verify);