From 087a03b3ea1c8d6e2d5743a8d1c6d571058caa04 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 13 Mar 2012 21:29:06 -0700 Subject: [PATCH 1/2] target: Fix compatible reservation handling (CRH=1) with legacy RESERVE/RELEASE This patch addresses a bug with target_check_scsi2_reservation_conflict() return checking in target_scsi2_reservation_[reserve,release]() that was preventing CRH=1 operation from silently succeeding in the two special cases defined by SPC-3, and not failing with reservation conflict status when dealing with legacy RESERVE/RELEASE + active SPC-3 PR logic. Also explictly set cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT during the early non reservation holder failure from pr_ops->t10_seq_non_holder() check in transport_generic_cmd_sequencer() for fabrics that already expect it to be set. This bug was originally introduced in mainline commit: commit eacac00ce5bfde8086cd0615fb53c986f7f970fe Author: Christoph Hellwig Date: Thu Nov 3 17:50:40 2011 -0400 target: split core_scsi2_emulate_crh Reported-by: Martin Svec Cc: Martin Svec Cc: Christoph Hellwig Cc: stable@vger.kernel.org Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_pr.c | 34 +++++++++++++++++--------- drivers/target/target_core_transport.c | 1 + 2 files changed, 23 insertions(+), 12 deletions(-) diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c index b7c779389eea..63e703bb6ac9 100644 --- a/drivers/target/target_core_pr.c +++ b/drivers/target/target_core_pr.c @@ -117,7 +117,7 @@ static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *, struct se_node_acl *, struct se_session *); static void core_scsi3_put_pr_reg(struct t10_pr_registration *); -static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd, int *ret) +static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd) { struct se_session *se_sess = cmd->se_sess; struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev; @@ -127,7 +127,7 @@ static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd, int *ret) int conflict = 0; if (!crh) - return false; + return -EINVAL; pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl, se_sess); @@ -155,16 +155,14 @@ static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd, int *ret) */ if (pr_reg->pr_res_holder) { core_scsi3_put_pr_reg(pr_reg); - *ret = 0; - return false; + return 1; } if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) || (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) || (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) || (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) { core_scsi3_put_pr_reg(pr_reg); - *ret = 0; - return true; + return 1; } core_scsi3_put_pr_reg(pr_reg); conflict = 1; @@ -189,10 +187,10 @@ static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd, int *ret) " while active SPC-3 registrations exist," " returning RESERVATION_CONFLICT\n"); cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT; - return true; + return -EBUSY; } - return false; + return 0; } int target_scsi2_reservation_release(struct se_task *task) @@ -201,12 +199,18 @@ int target_scsi2_reservation_release(struct se_task *task) struct se_device *dev = cmd->se_dev; struct se_session *sess = cmd->se_sess; struct se_portal_group *tpg = sess->se_tpg; - int ret = 0; + int ret = 0, rc; if (!sess || !tpg) goto out; - if (target_check_scsi2_reservation_conflict(cmd, &ret)) + rc = target_check_scsi2_reservation_conflict(cmd); + if (rc == 1) goto out; + else if (rc < 0) { + cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT; + ret = -EINVAL; + goto out; + } ret = 0; spin_lock(&dev->dev_reservation_lock); @@ -243,7 +247,7 @@ int target_scsi2_reservation_reserve(struct se_task *task) struct se_device *dev = cmd->se_dev; struct se_session *sess = cmd->se_sess; struct se_portal_group *tpg = sess->se_tpg; - int ret = 0; + int ret = 0, rc; if ((cmd->t_task_cdb[1] & 0x01) && (cmd->t_task_cdb[1] & 0x02)) { @@ -259,8 +263,14 @@ int target_scsi2_reservation_reserve(struct se_task *task) */ if (!sess || !tpg) goto out; - if (target_check_scsi2_reservation_conflict(cmd, &ret)) + rc = target_check_scsi2_reservation_conflict(cmd); + if (rc == 1) goto out; + else if (rc < 0) { + cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT; + ret = -EINVAL; + goto out; + } ret = 0; spin_lock(&dev->dev_reservation_lock); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 58cea07b12fb..cd5cd95812bb 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2539,6 +2539,7 @@ static int transport_generic_cmd_sequencer( cmd, cdb, pr_reg_type) != 0) { cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION; cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT; + cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT; cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT; return -EBUSY; } From 00fdc6bbef77844ce397a7de7acfaf25e8e2e4eb Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 13 Mar 2012 18:20:11 -0700 Subject: [PATCH 2/2] iscsi-target: Fix reservation conflict -EBUSY response handling bug This patch addresses a iscsi-target specific bug related to reservation conflict handling in iscsit_handle_scsi_cmd() that has been causing reservation conflicts to complete and not fail as expected due to incorrect errno checking. The problem occured with the change to return -EBUSY from transport_generic_cmd_sequencer() -> transport_generic_allocate_tasks() failures, that broke iscsit_handle_scsi_cmd() checking for -EINVAL in order to invoke a non GOOD status response. This was manifesting itself as data corruption with legacy SPC-2 reservations, but also effects iscsi-target LUNs with SPC-3 persistent reservations. This bug was originally introduced in lio-core commit: commit 03e98c9eb916f3f0868c1dc344dde2a60287ff72 Author: Nicholas Bellinger Date: Fri Nov 4 02:36:16 2011 -0700 target: Address legacy PYX_TRANSPORT_* return code breakage Reported-by: Martin Svec Cc: Martin Svec Cc: Christoph Hellwig Cc: stable@vger.kernel.org Signed-off-by: Nicholas Bellinger --- drivers/target/iscsi/iscsi_target.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 44262908def5..501b27c18145 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -1028,7 +1028,7 @@ done: return iscsit_add_reject_from_cmd( ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1, 1, buf, cmd); - } else if (transport_ret == -EINVAL) { + } else if (transport_ret < 0) { /* * Unsupported SAM Opcode. CHECK_CONDITION will be sent * in iscsit_execute_cmd() during the CmdSN OOO Execution