diff options
Diffstat (limited to 'drivers/scsi/sd.c')
| -rw-r--r-- | drivers/scsi/sd.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 8c525aa1b858..bd17cf8af013 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -107,6 +107,7 @@ static int sd_suspend(struct device *, pm_message_t state); static int sd_resume(struct device *); static void sd_rescan(struct device *); static int sd_done(struct scsi_cmnd *); +static int sd_eh_action(struct scsi_cmnd *, unsigned char *, int, int); static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer); static void scsi_disk_release(struct device *cdev); static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *); @@ -346,6 +347,31 @@ sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr, return count; } +static ssize_t +sd_show_max_medium_access_timeouts(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scsi_disk *sdkp = to_scsi_disk(dev); + + return snprintf(buf, 20, "%u\n", sdkp->max_medium_access_timeouts); +} + +static ssize_t +sd_store_max_medium_access_timeouts(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct scsi_disk *sdkp = to_scsi_disk(dev); + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + err = kstrtouint(buf, 10, &sdkp->max_medium_access_timeouts); + + return err ? err : count; +} + static struct device_attribute sd_disk_attrs[] = { __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type, sd_store_cache_type), @@ -360,6 +386,9 @@ static struct device_attribute sd_disk_attrs[] = { __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL), __ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode, sd_store_provisioning_mode), + __ATTR(max_medium_access_timeouts, S_IRUGO|S_IWUSR, + sd_show_max_medium_access_timeouts, + sd_store_max_medium_access_timeouts), __ATTR_NULL, }; @@ -382,6 +411,7 @@ static struct scsi_driver sd_template = { }, .rescan = sd_rescan, .done = sd_done, + .eh_action = sd_eh_action, }; /* @@ -1313,6 +1343,55 @@ static const struct block_device_operations sd_fops = { .unlock_native_capacity = sd_unlock_native_capacity, }; +/** + * sd_eh_action - error handling callback + * @scmd: sd-issued command that has failed + * @eh_cmnd: The command that was sent during error handling + * @eh_cmnd_len: Length of eh_cmnd in bytes + * @eh_disp: The recovery disposition suggested by the midlayer + * + * This function is called by the SCSI midlayer upon completion of + * an error handling command (TEST UNIT READY, START STOP UNIT, + * etc.) The command sent to the device by the error handler is + * stored in eh_cmnd. The result of sending the eh command is + * passed in eh_disp. + **/ +static int sd_eh_action(struct scsi_cmnd *scmd, unsigned char *eh_cmnd, + int eh_cmnd_len, int eh_disp) +{ + struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk); + + if (!scsi_device_online(scmd->device) || + !scsi_medium_access_command(scmd)) + return eh_disp; + + /* + * The device has timed out executing a medium access command. + * However, the TEST UNIT READY command sent during error + * handling completed successfully. Either the device is in the + * process of recovering or has it suffered an internal failure + * that prevents access to the storage medium. + */ + if (host_byte(scmd->result) == DID_TIME_OUT && eh_disp == SUCCESS && + eh_cmnd_len && eh_cmnd[0] == TEST_UNIT_READY) + sdkp->medium_access_timed_out++; + + /* + * If the device keeps failing read/write commands but TEST UNIT + * READY always completes successfully we assume that medium + * access is no longer possible and take the device offline. + */ + if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) { + scmd_printk(KERN_ERR, scmd, + "Medium access timeout failure. Offlining disk!\n"); + scsi_device_set_state(scmd->device, SDEV_OFFLINE); + + return FAILED; + } + + return eh_disp; +} + static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd) { u64 start_lba = blk_rq_pos(scmd->request); @@ -1402,6 +1481,8 @@ static int sd_done(struct scsi_cmnd *SCpnt) (!sense_valid || sense_deferred)) goto out; + sdkp->medium_access_timed_out = 0; + switch (sshdr.sense_key) { case HARDWARE_ERROR: case MEDIUM_ERROR: @@ -2523,6 +2604,7 @@ static void sd_probe_async(void *data, async_cookie_t cookie) sdkp->RCD = 0; sdkp->ATO = 0; sdkp->first_scan = 1; + sdkp->max_medium_access_timeouts = SD_MAX_MEDIUM_TIMEOUTS; sd_revalidate_disk(gd); |
