From 8e8c9d01c5ea33e0d21f13264a9caeed255526d1 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Thu, 6 Apr 2017 15:36:33 +0200 Subject: [PATCH] scsi: make eh_eflags persistent If a failed command is retried and fails again we need to enter SCSI EH, otherwise we will never be able to recover the command. To detect this situation we must not clear scmd->eh_eflags when EH finishes but rather make it persistent throughout the lifetime of the command. Signed-off-by: Hannes Reinecke Reviewed-by: Benjamin Block Reviewed-by: Bart Van Assche Reviewed-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen --- Documentation/scsi/scsi_eh.txt | 14 +++++++------- drivers/scsi/libsas/sas_scsi_host.c | 2 -- drivers/scsi/scsi_error.c | 4 ++-- include/scsi/scsi_eh.h | 1 + 4 files changed, 10 insertions(+), 11 deletions(-) diff --git a/Documentation/scsi/scsi_eh.txt b/Documentation/scsi/scsi_eh.txt index 37eca00796ee..4edb9c1cbef5 100644 --- a/Documentation/scsi/scsi_eh.txt +++ b/Documentation/scsi/scsi_eh.txt @@ -105,11 +105,14 @@ function 2. If the host supports asynchronous completion (as indicated by the no_async_abort setting in the host template) scsi_abort_command() - is invoked to schedule an asynchrous abort. If that fails - Step #3 is taken. + is invoked to schedule an asynchrous abort. + Asynchronous abort are not invoked for commands which the + SCSI_EH_ABORT_SCHEDULED flag is set (this indicates that the command + already had been aborted once, and this is a retry which failed), + or when the EH deadline is expired. In these case Step #3 is taken. - 2. scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD) is invoked for the - command. See [1-3] for more information. + 3. scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD) is invoked for the + command. See [1-4] for more information. [1-3] Asynchronous command aborts @@ -263,7 +266,6 @@ scmd->allowed. 3. scmd recovered ACTION: scsi_eh_finish_cmd() is invoked to EH-finish scmd - - clear scmd->eh_eflags - scsi_setup_cmd_retry() - move from local eh_work_q to local eh_done_q LOCKING: none @@ -456,8 +458,6 @@ except for #1 must be implemented by eh_strategy_handler(). - shost->host_failed is zero. - - Each scmd's eh_eflags field is cleared. - - Each scmd is in such a state that scsi_setup_cmd_retry() on the scmd doesn't make any difference. diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c index ee6b39a1db69..87e5079d816b 100644 --- a/drivers/scsi/libsas/sas_scsi_host.c +++ b/drivers/scsi/libsas/sas_scsi_host.c @@ -613,8 +613,6 @@ static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head * SAS_DPRINTK("trying to find task 0x%p\n", task); res = sas_scsi_find_task(task); - cmd->eh_eflags = 0; - switch (res) { case TASK_IS_DONE: SAS_DPRINTK("%s: task 0x%p is done\n", __func__, diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index cff7d9de79f2..4d26ff215c74 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -188,7 +188,6 @@ scsi_abort_command(struct scsi_cmnd *scmd) /* * Retry after abort failed, escalate to next level. */ - scmd->eh_eflags &= ~SCSI_EH_ABORT_SCHEDULED; SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_INFO, scmd, "previous abort failed\n")); @@ -937,6 +936,7 @@ void scsi_eh_prep_cmnd(struct scsi_cmnd *scmd, struct scsi_eh_save *ses, ses->result = scmd->result; ses->underflow = scmd->underflow; ses->prot_op = scmd->prot_op; + ses->eh_eflags = scmd->eh_eflags; scmd->prot_op = SCSI_PROT_NORMAL; scmd->eh_eflags = 0; @@ -1000,6 +1000,7 @@ void scsi_eh_restore_cmnd(struct scsi_cmnd* scmd, struct scsi_eh_save *ses) scmd->result = ses->result; scmd->underflow = ses->underflow; scmd->prot_op = ses->prot_op; + scmd->eh_eflags = ses->eh_eflags; } EXPORT_SYMBOL(scsi_eh_restore_cmnd); @@ -1132,7 +1133,6 @@ static int scsi_eh_action(struct scsi_cmnd *scmd, int rtn) */ void scsi_eh_finish_cmd(struct scsi_cmnd *scmd, struct list_head *done_q) { - scmd->eh_eflags = 0; list_move_tail(&scmd->eh_entry, done_q); } EXPORT_SYMBOL(scsi_eh_finish_cmd); diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h index 98d366b55770..a25b3285dd6f 100644 --- a/include/scsi/scsi_eh.h +++ b/include/scsi/scsi_eh.h @@ -31,6 +31,7 @@ extern int scsi_ioctl_reset(struct scsi_device *, int __user *); struct scsi_eh_save { /* saved state */ int result; + int eh_eflags; enum dma_data_direction data_direction; unsigned underflow; unsigned char cmd_len; -- 2.20.1