From d6dfc868bcf329392abd1ecfa7357eb51ebf8c30 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Mon, 16 Jul 2012 11:04:39 -0700 Subject: [PATCH] target: Allow for target_submit_cmd() returning errors We want it to be possible for target_submit_cmd() to return errors up to its fabric module callers. For now just update the prototype to return an int, and update all callers to handle non-zero return values as an error. This is immediately useful for tcm_qla2xxx to fix a long-standing active I/O session shutdown race, but tcm_fc, usb-gadget, and sbp-target the fabric maintainers need to check + ACK that handling a target_submit_cmd() failure due to session shutdown does not introduce regressions (nab: Respin against for-next after initial NACK + update docbook comment + fix double se_cmd init in exception path for usb-gadget) Cc: Chad Dupuis Cc: Arun Easi Cc: Chris Boot Cc: Stefan Richter Cc: Mark Rustad Cc: Sebastian Andrzej Siewior Cc: Felipe Balbi Cc: Andy Grover Signed-off-by: Roland Dreier Signed-off-by: Nicholas Bellinger --- drivers/scsi/qla2xxx/tcm_qla2xxx.c | 3 +-- drivers/target/sbp/sbp_target.c | 8 +++++--- drivers/target/target_core_transport.c | 14 ++++++++----- drivers/target/tcm_fc/tfc_cmd.c | 8 +++++--- drivers/usb/gadget/tcm_usb_gadget.c | 36 +++++++++++++++++++++------------- include/target/target_core_fabric.h | 2 +- 6 files changed, 43 insertions(+), 28 deletions(-) diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c index 65a7ed9..4752f65 100644 --- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c +++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c @@ -597,10 +597,9 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd, return -EINVAL; } - target_submit_cmd(se_cmd, se_sess, cdb, &cmd->sense_buffer[0], + return target_submit_cmd(se_cmd, se_sess, cdb, &cmd->sense_buffer[0], cmd->unpacked_lun, data_length, fcp_task_attr, data_dir, flags); - return 0; } static void tcm_qla2xxx_handle_data_work(struct work_struct *work) diff --git a/drivers/target/sbp/sbp_target.c b/drivers/target/sbp/sbp_target.c index e10e622..39ddba5 100644 --- a/drivers/target/sbp/sbp_target.c +++ b/drivers/target/sbp/sbp_target.c @@ -1235,9 +1235,11 @@ static void sbp_handle_command(struct sbp_target_request *req) pr_debug("sbp_handle_command ORB:0x%llx unpacked_lun:%d data_len:%d data_dir:%d\n", req->orb_pointer, unpacked_lun, data_length, data_dir); - target_submit_cmd(&req->se_cmd, sess->se_sess, req->cmd_buf, - req->sense_buf, unpacked_lun, data_length, - MSG_SIMPLE_TAG, data_dir, 0); + if (target_submit_cmd(&req->se_cmd, sess->se_sess, req->cmd_buf, + req->sense_buf, unpacked_lun, data_length, + MSG_SIMPLE_TAG, data_dir, 0)) + goto err; + return; err: diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 14e54b4..7647eca 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1447,10 +1447,14 @@ EXPORT_SYMBOL(transport_handle_cdb_direct); * @data_dir: DMA data direction * @flags: flags for command submission from target_sc_flags_tables * + * Returns non zero to signal active I/O shutdown failure. All other + * setup exceptions will be returned as a SCSI CHECK_CONDITION response, + * but still return zero here. + * * This may only be called from process context, and also currently * assumes internal allocation of fabric payload buffer by target-core. **/ -void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, +int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *cdb, unsigned char *sense, u32 unpacked_lun, u32 data_length, int task_attr, int data_dir, int flags) { @@ -1478,7 +1482,7 @@ void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, */ rc = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF)); if (rc) - return; + return rc; /* * Signal bidirectional data payloads to target-core */ @@ -1491,13 +1495,13 @@ void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, transport_send_check_condition_and_sense(se_cmd, se_cmd->scsi_sense_reason, 0); target_put_sess_cmd(se_sess, se_cmd); - return; + return 0; } rc = target_setup_cmd_from_cdb(se_cmd, cdb); if (rc != 0) { transport_generic_request_failure(se_cmd); - return; + return 0; } /* @@ -1507,7 +1511,7 @@ void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, core_alua_check_nonop_delay(se_cmd); transport_handle_cdb_direct(se_cmd); - return; + return 0; } EXPORT_SYMBOL(target_submit_cmd); diff --git a/drivers/target/tcm_fc/tfc_cmd.c b/drivers/target/tcm_fc/tfc_cmd.c index 4ad58ac..b9cb500 100644 --- a/drivers/target/tcm_fc/tfc_cmd.c +++ b/drivers/target/tcm_fc/tfc_cmd.c @@ -543,9 +543,11 @@ static void ft_send_work(struct work_struct *work) * Use a single se_cmd->cmd_kref as we expect to release se_cmd * directly from ft_check_stop_free callback in response path. */ - target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb, - &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun), - ntohl(fcp->fc_dl), task_attr, data_dir, 0); + if (target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb, + &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun), + ntohl(fcp->fc_dl), task_attr, data_dir, 0)) + goto err; + pr_debug("r_ctl %x alloc target_submit_cmd\n", fh->fh_r_ctl); return; diff --git a/drivers/usb/gadget/tcm_usb_gadget.c b/drivers/usb/gadget/tcm_usb_gadget.c index 02ace18..5444866 100644 --- a/drivers/usb/gadget/tcm_usb_gadget.c +++ b/drivers/usb/gadget/tcm_usb_gadget.c @@ -1065,16 +1065,20 @@ static void usbg_cmd_work(struct work_struct *work) tv_nexus->tvn_se_sess->se_tpg->se_tpg_tfo, tv_nexus->tvn_se_sess, cmd->data_len, DMA_NONE, cmd->prio_attr, cmd->sense_iu.sense); - - transport_send_check_condition_and_sense(se_cmd, - TCM_UNSUPPORTED_SCSI_OPCODE, 1); - usbg_cleanup_cmd(cmd); - return; + goto out; } - target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess, + if (target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess, cmd->cmd_buf, cmd->sense_iu.sense, cmd->unpacked_lun, - 0, cmd->prio_attr, dir, TARGET_SCF_UNKNOWN_SIZE); + 0, cmd->prio_attr, dir, TARGET_SCF_UNKNOWN_SIZE) < 0) + goto out; + + return; + +out: + transport_send_check_condition_and_sense(se_cmd, + TCM_UNSUPPORTED_SCSI_OPCODE, 1); + usbg_cleanup_cmd(cmd); } static int usbg_submit_command(struct f_uas *fu, @@ -1177,16 +1181,20 @@ static void bot_cmd_work(struct work_struct *work) tv_nexus->tvn_se_sess->se_tpg->se_tpg_tfo, tv_nexus->tvn_se_sess, cmd->data_len, DMA_NONE, cmd->prio_attr, cmd->sense_iu.sense); - - transport_send_check_condition_and_sense(se_cmd, - TCM_UNSUPPORTED_SCSI_OPCODE, 1); - usbg_cleanup_cmd(cmd); - return; + goto out; } - target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess, + if (target_submit_cmd(se_cmd, tv_nexus->tvn_se_sess, cmd->cmd_buf, cmd->sense_iu.sense, cmd->unpacked_lun, - cmd->data_len, cmd->prio_attr, dir, 0); + cmd->data_len, cmd->prio_attr, dir, 0) < 0) + goto out; + + return; + +out: + transport_send_check_condition_and_sense(se_cmd, + TCM_UNSUPPORTED_SCSI_OPCODE, 1); + usbg_cleanup_cmd(cmd); } static int bot_submit_command(struct f_uas *fu, diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 815e064..69fb3cf 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -102,7 +102,7 @@ void transport_init_se_cmd(struct se_cmd *, struct target_core_fabric_ops *, struct se_session *, u32, int, int, unsigned char *); int transport_lookup_cmd_lun(struct se_cmd *, u32); int target_setup_cmd_from_cdb(struct se_cmd *, unsigned char *); -void target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *, +int target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *, unsigned char *, u32, u32, int, int, int); int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *sense, u32 unpacked_lun, -- 1.7.12