From 96902835e7e2c7bf59db28ffd550852610169a2d Mon Sep 17 00:00:00 2001 From: Calvin Owens Date: Thu, 28 Jul 2016 21:38:20 -0700 Subject: [PATCH] mpt3sas: Eliminate conditional locking in mpt3sas_scsih_issue_tm() This flag that conditionally acquires the mutex is confusing and prone to bugginess: refactor it into two separate function calls, and make the unlocked one complain if it's called outside the mutex. Signed-off-by: Calvin Owens Acked-by: Chaitra P B Signed-off-by: Martin K. Petersen --- drivers/scsi/mpt3sas/mpt3sas_base.h | 16 +++------ drivers/scsi/mpt3sas/mpt3sas_ctl.c | 5 ++- drivers/scsi/mpt3sas/mpt3sas_scsih.c | 66 +++++++++++++++++------------------- 3 files changed, 38 insertions(+), 49 deletions(-) diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h index eb7f5b0..f0baafd 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_base.h +++ b/drivers/scsi/mpt3sas/mpt3sas_base.h @@ -794,16 +794,6 @@ struct reply_post_struct { dma_addr_t reply_post_free_dma; }; -/** - * enum mutex_type - task management mutex type - * @TM_MUTEX_OFF: mutex is not required becuase calling function is acquiring it - * @TM_MUTEX_ON: mutex is required - */ -enum mutex_type { - TM_MUTEX_OFF = 0, - TM_MUTEX_ON = 1, -}; - typedef void (*MPT3SAS_FLUSH_RUNNING_CMDS)(struct MPT3SAS_ADAPTER *ioc); /** * struct MPT3SAS_ADAPTER - per adapter struct @@ -1291,7 +1281,11 @@ void mpt3sas_scsih_reset_handler(struct MPT3SAS_ADAPTER *ioc, int reset_phase); int mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, uint id, uint lun, u8 type, u16 smid_task, - ulong timeout, enum mutex_type m_type); + ulong timeout); +int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, + uint channel, uint id, uint lun, u8 type, u16 smid_task, + ulong timeout); + void mpt3sas_scsih_set_tm_flag(struct MPT3SAS_ADAPTER *ioc, u16 handle); void mpt3sas_scsih_clear_tm_flag(struct MPT3SAS_ADAPTER *ioc, u16 handle); void mpt3sas_expander_remove(struct MPT3SAS_ADAPTER *ioc, u64 sas_address); diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c index 7d00f09..75ae533 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c @@ -1001,10 +1001,9 @@ _ctl_do_mpt_command(struct MPT3SAS_ADAPTER *ioc, struct mpt3_ioctl_command karg, ioc->name, le16_to_cpu(mpi_request->FunctionDependent1)); mpt3sas_halt_firmware(ioc); - mpt3sas_scsih_issue_tm(ioc, + mpt3sas_scsih_issue_locked_tm(ioc, le16_to_cpu(mpi_request->FunctionDependent1), 0, 0, - 0, MPI2_SCSITASKMGMT_TASKTYPE_TARGET_RESET, 0, 30, - TM_MUTEX_ON); + 0, MPI2_SCSITASKMGMT_TASKTYPE_TARGET_RESET, 0, 30); } else mpt3sas_base_hard_reset_handler(ioc, CAN_SLEEP, FORCE_BIG_HAMMER); diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c index acabe48..c93a7ba 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c @@ -2201,7 +2201,6 @@ mpt3sas_scsih_clear_tm_flag(struct MPT3SAS_ADAPTER *ioc, u16 handle) * @type: MPI2_SCSITASKMGMT_TASKTYPE__XXX (defined in mpi2_init.h) * @smid_task: smid assigned to the task * @timeout: timeout in seconds - * @m_type: TM_MUTEX_ON or TM_MUTEX_OFF * Context: user * * A generic API for sending task management requests to firmware. @@ -2212,8 +2211,7 @@ mpt3sas_scsih_clear_tm_flag(struct MPT3SAS_ADAPTER *ioc, u16 handle) */ int mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, - uint id, uint lun, u8 type, u16 smid_task, ulong timeout, - enum mutex_type m_type) + uint id, uint lun, u8 type, u16 smid_task, ulong timeout) { Mpi2SCSITaskManagementRequest_t *mpi_request; Mpi2SCSITaskManagementReply_t *mpi_reply; @@ -2224,21 +2222,19 @@ mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, int rc; u16 msix_task = 0; - if (m_type == TM_MUTEX_ON) - mutex_lock(&ioc->tm_cmds.mutex); + lockdep_assert_held(&ioc->tm_cmds.mutex); + if (ioc->tm_cmds.status != MPT3_CMD_NOT_USED) { pr_info(MPT3SAS_FMT "%s: tm_cmd busy!!!\n", __func__, ioc->name); - rc = FAILED; - goto err_out; + return FAILED; } if (ioc->shost_recovery || ioc->remove_host || ioc->pci_error_recovery) { pr_info(MPT3SAS_FMT "%s: host reset in progress!\n", __func__, ioc->name); - rc = FAILED; - goto err_out; + return FAILED; } ioc_state = mpt3sas_base_get_iocstate(ioc, 0); @@ -2247,8 +2243,7 @@ mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, "unexpected doorbell active!\n", ioc->name)); rc = mpt3sas_base_hard_reset_handler(ioc, CAN_SLEEP, FORCE_BIG_HAMMER); - rc = (!rc) ? SUCCESS : FAILED; - goto err_out; + return (!rc) ? SUCCESS : FAILED; } if ((ioc_state & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT) { @@ -2256,16 +2251,14 @@ mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, MPI2_DOORBELL_DATA_MASK); rc = mpt3sas_base_hard_reset_handler(ioc, CAN_SLEEP, FORCE_BIG_HAMMER); - rc = (!rc) ? SUCCESS : FAILED; - goto err_out; + return (!rc) ? SUCCESS : FAILED; } smid = mpt3sas_base_get_smid_hpr(ioc, ioc->tm_cb_idx); if (!smid) { pr_err(MPT3SAS_FMT "%s: failed obtaining a smid\n", ioc->name, __func__); - rc = FAILED; - goto err_out; + return FAILED; } if (type == MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK) @@ -2302,9 +2295,7 @@ mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, rc = mpt3sas_base_hard_reset_handler(ioc, CAN_SLEEP, FORCE_BIG_HAMMER); rc = (!rc) ? SUCCESS : FAILED; - ioc->tm_cmds.status = MPT3_CMD_NOT_USED; - mpt3sas_scsih_clear_tm_flag(ioc, handle); - goto err_out; + goto out; } } @@ -2356,17 +2347,23 @@ mpt3sas_scsih_issue_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, uint channel, break; } +out: mpt3sas_scsih_clear_tm_flag(ioc, handle); ioc->tm_cmds.status = MPT3_CMD_NOT_USED; - if (m_type == TM_MUTEX_ON) - mutex_unlock(&ioc->tm_cmds.mutex); - return rc; +} - err_out: - if (m_type == TM_MUTEX_ON) - mutex_unlock(&ioc->tm_cmds.mutex); - return rc; +int mpt3sas_scsih_issue_locked_tm(struct MPT3SAS_ADAPTER *ioc, u16 handle, + uint channel, uint id, uint lun, u8 type, u16 smid_task, ulong timeout) +{ + int ret; + + mutex_lock(&ioc->tm_cmds.mutex); + ret = mpt3sas_scsih_issue_tm(ioc, handle, channel, id, lun, type, + smid_task, timeout); + mutex_unlock(&ioc->tm_cmds.mutex); + + return ret; } /** @@ -2482,9 +2479,9 @@ scsih_abort(struct scsi_cmnd *scmd) mpt3sas_halt_firmware(ioc); handle = sas_device_priv_data->sas_target->handle; - r = mpt3sas_scsih_issue_tm(ioc, handle, scmd->device->channel, + r = mpt3sas_scsih_issue_locked_tm(ioc, handle, scmd->device->channel, scmd->device->id, scmd->device->lun, - MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, smid, 30, TM_MUTEX_ON); + MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, smid, 30); out: sdev_printk(KERN_INFO, scmd->device, "task abort: %s scmd(%p)\n", @@ -2541,9 +2538,9 @@ scsih_dev_reset(struct scsi_cmnd *scmd) goto out; } - r = mpt3sas_scsih_issue_tm(ioc, handle, scmd->device->channel, + r = mpt3sas_scsih_issue_locked_tm(ioc, handle, scmd->device->channel, scmd->device->id, scmd->device->lun, - MPI2_SCSITASKMGMT_TASKTYPE_LOGICAL_UNIT_RESET, 0, 30, TM_MUTEX_ON); + MPI2_SCSITASKMGMT_TASKTYPE_LOGICAL_UNIT_RESET, 0, 30); out: sdev_printk(KERN_INFO, scmd->device, "device reset: %s scmd(%p)\n", @@ -2603,9 +2600,9 @@ scsih_target_reset(struct scsi_cmnd *scmd) goto out; } - r = mpt3sas_scsih_issue_tm(ioc, handle, scmd->device->channel, + r = mpt3sas_scsih_issue_locked_tm(ioc, handle, scmd->device->channel, scmd->device->id, 0, MPI2_SCSITASKMGMT_TASKTYPE_TARGET_RESET, 0, - 30, TM_MUTEX_ON); + 30); out: starget_printk(KERN_INFO, starget, "target reset: %s scmd(%p)\n", @@ -6089,8 +6086,7 @@ _scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc, spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags); r = mpt3sas_scsih_issue_tm(ioc, handle, 0, 0, lun, - MPI2_SCSITASKMGMT_TASKTYPE_QUERY_TASK, smid, 30, - TM_MUTEX_OFF); + MPI2_SCSITASKMGMT_TASKTYPE_QUERY_TASK, smid, 30); if (r == FAILED) { sdev_printk(KERN_WARNING, sdev, "mpt3sas_scsih_issue_tm: FAILED when sending " @@ -6130,8 +6126,8 @@ _scsih_sas_broadcast_primitive_event(struct MPT3SAS_ADAPTER *ioc, goto out_no_lock; r = mpt3sas_scsih_issue_tm(ioc, handle, sdev->channel, sdev->id, - sdev->lun, MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, smid, 30, - TM_MUTEX_OFF); + sdev->lun, MPI2_SCSITASKMGMT_TASKTYPE_ABORT_TASK, smid, + 30); if (r == FAILED) { sdev_printk(KERN_WARNING, sdev, "mpt3sas_scsih_issue_tm: ABORT_TASK: FAILED : " -- 2.7.4