From 85cffefa09e448906a6f0bc20f422d75a18675bd Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 8 Aug 2019 20:02:06 -0700 Subject: scsi: qla2xxx: Fix a race condition between aborting and completing a SCSI command Instead of allocating a struct srb dynamically from inside .queuecommand(), set qla2xxx_driver_template.cmd_size such that struct scsi_cmnd and struct srb are contiguous. Do not call QLA_QPAIR_MARK_BUSY() / QLA_QPAIR_MARK_NOT_BUSY() for SRBs associated with SCSI commands. That is safe because scsi_remove_host() is called before queue pairs are deleted and scsi_remove_host() waits for all outstanding SCSI commands to finish. Cc: Himanshu Madhani Signed-off-by: Bart Van Assche Tested-by: Himanshu Madhani Reviewed-by: Himanshu Madhani Signed-off-by: Martin K. Petersen --- drivers/scsi/qla2xxx/qla_def.h | 1 - drivers/scsi/qla2xxx/qla_os.c | 45 ++++++++---------------------------------- 2 files changed, 8 insertions(+), 38 deletions(-) (limited to 'drivers/scsi/qla2xxx') diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h index 65d79bcb7ccf..3ffe7661a25b 100644 --- a/drivers/scsi/qla2xxx/qla_def.h +++ b/drivers/scsi/qla2xxx/qla_def.h @@ -630,7 +630,6 @@ typedef struct srb { } srb_t; #define GET_CMD_SP(sp) (sp->u.scmd.cmd) -#define SET_CMD_SP(sp, cmd) (sp->u.scmd.cmd = cmd) #define GET_CMD_CTX_SP(sp) (sp->u.scmd.ctx) #define GET_CMD_SENSE_LEN(sp) \ diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c index 9ef59995f5d6..5ca7f7913258 100644 --- a/drivers/scsi/qla2xxx/qla_os.c +++ b/drivers/scsi/qla2xxx/qla_os.c @@ -713,7 +713,6 @@ void qla2x00_sp_compl(srb_t *sp, int res) cmd->scsi_done(cmd); if (comp) complete(comp); - qla2x00_rel_sp(sp); } void qla2xxx_qpair_sp_free_dma(srb_t *sp) @@ -814,7 +813,6 @@ void qla2xxx_qpair_sp_compl(srb_t *sp, int res) cmd->scsi_done(cmd); if (comp) complete(comp); - qla2xxx_rel_qpair_sp(sp->qpair, sp); } static int @@ -908,9 +906,8 @@ qla2xxx_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) else goto qc24_target_busy; - sp = qla2x00_get_sp(vha, fcport, GFP_ATOMIC); - if (!sp) - goto qc24_host_busy; + sp = scsi_cmd_priv(cmd); + qla2xxx_init_sp(sp, vha, vha->hw->base_qpair, fcport); sp->u.scmd.cmd = cmd; sp->type = SRB_SCSI_CMD; @@ -931,9 +928,6 @@ qla2xxx_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) qc24_host_busy_free_sp: sp->free(sp); -qc24_host_busy: - return SCSI_MLQUEUE_HOST_BUSY; - qc24_target_busy: return SCSI_MLQUEUE_TARGET_BUSY; @@ -994,9 +988,8 @@ qla2xxx_mqueuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd, else goto qc24_target_busy; - sp = qla2xxx_get_qpair_sp(vha, qpair, fcport, GFP_ATOMIC); - if (!sp) - goto qc24_host_busy; + sp = scsi_cmd_priv(cmd); + qla2xxx_init_sp(sp, vha, qpair, fcport); sp->u.scmd.cmd = cmd; sp->type = SRB_SCSI_CMD; @@ -1020,9 +1013,6 @@ qla2xxx_mqueuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd, qc24_host_busy_free_sp: sp->free(sp); -qc24_host_busy: - return SCSI_MLQUEUE_HOST_BUSY; - qc24_target_busy: return SCSI_MLQUEUE_TARGET_BUSY; @@ -1257,10 +1247,8 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd) int ret; unsigned int id; uint64_t lun; - unsigned long flags; int rval; struct qla_hw_data *ha = vha->hw; - struct qla_qpair *qpair; if (qla2x00_isp_reg_stat(ha)) { ql_log(ql_log_info, vha, 0x8042, @@ -1272,32 +1260,14 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd) if (ret != 0) return ret; - sp = (srb_t *) CMD_SP(cmd); - if (!sp) - return SUCCESS; - - qpair = sp->qpair; - if (!qpair) - return SUCCESS; + sp = scsi_cmd_priv(cmd); if (sp->fcport && sp->fcport->deleted) return SUCCESS; - spin_lock_irqsave(qpair->qp_lock_ptr, flags); - if (sp->type != SRB_SCSI_CMD || GET_CMD_SP(sp) != cmd) { - /* there's a chance an interrupt could clear - the ptr as part of done & free */ - spin_unlock_irqrestore(qpair->qp_lock_ptr, flags); - return SUCCESS; - } - - /* Get a reference to the sp and drop the lock. */ - if (sp_get(sp)){ - /* ref_count is already 0 */ - spin_unlock_irqrestore(qpair->qp_lock_ptr, flags); + /* Return if the command has already finished. */ + if (sp_get(sp)) return SUCCESS; - } - spin_unlock_irqrestore(qpair->qp_lock_ptr, flags); id = cmd->device->id; lun = cmd->device->lun; @@ -7159,6 +7129,7 @@ struct scsi_host_template qla2xxx_driver_template = { .supported_mode = MODE_INITIATOR, .track_queue_depth = 1, + .cmd_size = sizeof(srb_t), }; static const struct pci_error_handlers qla2xxx_err_handler = { -- cgit