From 706d5860969b3b24d65d9a57bd3bb5e4a1419c08 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Thu, 28 Jul 2011 00:07:03 -0700 Subject: [PATCH] target: Add WRITE_SAME (10) parsing and refactor passthrough checks This patch adds initial WRITE_SAME (10) w/ UNMAP=1 support following updates in sbcr26 to allow UNMAP=1 for the non 16 + 32 byte CDB case. It also refactors current pSCSI passthrough passthrough checks into target_check_write_same_discard() ahead of UNMAP=0 w/ write payload support into target_core_iblock.c. This includes the support for handling WRITE_SAME in transport_emulate_control_cdb(), and converts target_emulate_write_same to accept num_blocks directly for WRITE_SAME, WRITE_SAME_16 and WRITE_SAME_32. Reported-by: Eric Seppanen Cc: Roland Dreier Cc: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_cdb.c | 28 ++++--- drivers/target/target_core_transport.c | 102 ++++++++++++++----------- 2 files changed, 73 insertions(+), 57 deletions(-) diff --git a/drivers/target/target_core_cdb.c b/drivers/target/target_core_cdb.c index d095408dbd5f..4c1d3a98e894 100644 --- a/drivers/target/target_core_cdb.c +++ b/drivers/target/target_core_cdb.c @@ -1090,24 +1090,17 @@ err: * Note this is not used for TCM/pSCSI passthrough */ static int -target_emulate_write_same(struct se_task *task, int write_same32) +target_emulate_write_same(struct se_task *task, u32 num_blocks) { struct se_cmd *cmd = task->task_se_cmd; struct se_device *dev = cmd->se_dev; sector_t range; sector_t lba = cmd->t_task_lba; - unsigned int num_blocks; int ret; /* - * Extract num_blocks from the WRITE_SAME_* CDB. Then use the explict - * range when non zero is supplied, otherwise calculate the remaining - * range based on ->get_blocks() - starting LBA. + * Use the explicit range when non zero is supplied, otherwise calculate + * the remaining range based on ->get_blocks() - starting LBA. */ - if (write_same32) - num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]); - else - num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]); - if (num_blocks != 0) range = num_blocks; else @@ -1170,13 +1163,23 @@ transport_emulate_control_cdb(struct se_task *task) } ret = target_emulate_unmap(task); break; + case WRITE_SAME: + if (!dev->transport->do_discard) { + pr_err("WRITE_SAME emulation not supported" + " for: %s\n", dev->transport->name); + return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE; + } + ret = target_emulate_write_same(task, + get_unaligned_be16(&cmd->t_task_cdb[7])); + break; case WRITE_SAME_16: if (!dev->transport->do_discard) { pr_err("WRITE_SAME_16 emulation not supported" " for: %s\n", dev->transport->name); return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE; } - ret = target_emulate_write_same(task, 0); + ret = target_emulate_write_same(task, + get_unaligned_be32(&cmd->t_task_cdb[10])); break; case VARIABLE_LENGTH_CMD: service_action = @@ -1189,7 +1192,8 @@ transport_emulate_control_cdb(struct se_task *task) dev->transport->name); return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE; } - ret = target_emulate_write_same(task, 1); + ret = target_emulate_write_same(task, + get_unaligned_be32(&cmd->t_task_cdb[28])); break; default: pr_err("Unsupported VARIABLE_LENGTH_CMD SA:" diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index fd7d4518b8ef..eb8055aa6e61 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2861,6 +2861,38 @@ static int transport_cmd_get_valid_sectors(struct se_cmd *cmd) return sectors; } +static int target_check_write_same_discard(unsigned char *flags, struct se_device *dev) +{ + /* + * Determine if the received WRITE_SAME is used to for direct + * passthrough into Linux/SCSI with struct request via TCM/pSCSI + * or we are signaling the use of internal WRITE_SAME + UNMAP=1 + * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK code. + */ + int passthrough = (dev->transport->transport_type == + TRANSPORT_PLUGIN_PHBA_PDEV); + + if (!passthrough) { + 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; +} + /* transport_generic_cmd_sequencer(): * * Generic Command Sequencer that should work for most DAS transport @@ -3081,27 +3113,9 @@ static int transport_generic_cmd_sequencer( cmd->t_task_lba = get_unaligned_be64(&cdb[12]); cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB; - /* - * Skip the remaining assignments for TCM/PSCSI passthrough - */ - if (passthrough) - break; - - if ((cdb[10] & 0x04) || (cdb[10] & 0x02)) { - pr_err("WRITE_SAME PBDATA and LBDATA" - " bits not supported for Block Discard" - " Emulation\n"); + if (target_check_write_same_discard(&cdb[10], dev) < 0) goto out_invalid_cdb_field; - } - /* - * Currently for the emulated case we only accept - * tpws with the UNMAP=1 bit set. - */ - if (!(cdb[10] & 0x08)) { - pr_err("WRITE_SAME w/o UNMAP bit not" - " supported for Block Discard Emulation\n"); - goto out_invalid_cdb_field; - } + break; default: pr_err("VARIABLE_LENGTH_CMD service action" @@ -3358,33 +3372,31 @@ static int transport_generic_cmd_sequencer( } cmd->t_task_lba = get_unaligned_be64(&cdb[2]); - passthrough = (dev->transport->transport_type == - TRANSPORT_PLUGIN_PHBA_PDEV); - /* - * Determine if the received WRITE_SAME_16 is used to for direct - * passthrough into Linux/SCSI with struct request via TCM/pSCSI - * or we are signaling the use of internal WRITE_SAME + UNMAP=1 - * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK and - * TCM/FILEIO subsystem plugin backstores. - */ - if (!passthrough) { - if ((cdb[1] & 0x04) || (cdb[1] & 0x02)) { - pr_err("WRITE_SAME PBDATA and LBDATA" - " bits not supported for Block Discard" - " Emulation\n"); - goto out_invalid_cdb_field; - } - /* - * Currently for the emulated case we only accept - * tpws with the UNMAP=1 bit set. - */ - if (!(cdb[1] & 0x08)) { - pr_err("WRITE_SAME w/o UNMAP bit not " - " supported for Block Discard Emulation\n"); - goto out_invalid_cdb_field; - } + cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB; + + if (target_check_write_same_discard(&cdb[1], dev) < 0) + goto out_invalid_cdb_field; + break; + case WRITE_SAME: + sectors = transport_get_sectors_10(cdb, cmd, §or_ret); + if (sector_ret) + goto out_unsupported_cdb; + + if (sectors) + size = transport_get_size(sectors, cdb, cmd); + else { + pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n"); + goto out_invalid_cdb_field; } + + cmd->t_task_lba = get_unaligned_be32(&cdb[2]); cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB; + /* + * Follow sbcr26 with WRITE_SAME (10) and check for the existence + * of byte 1 bit 3 UNMAP instead of original reserved field + */ + if (target_check_write_same_discard(&cdb[1], dev) < 0) + goto out_invalid_cdb_field; break; case ALLOW_MEDIUM_REMOVAL: case GPCMD_CLOSE_TRACK: -- 2.39.5