From: Scott Teel <scott.t...@hp.com> Allow SSD Smart Path for a controller to be disabled by the user, regardless of settings in controller firmware or array configuration.
To disable: echo 0 > /sys/class/scsi_host/host<id>/acciopath_status To re-enable: echo 1 > /sys/class/scsi_host/host<id>/acciopath_status To check state: cat /sys/class/scsi_host/host<id>/acciopath_status Signed-off-by: Scott Teel <scott.t...@hp.com> Acked-by: Stephen M. Cameron <scame...@beardog.cce.hp.com> --- Documentation/ABI/testing/sysfs-class-scsi_host | 16 ++++++++ drivers/scsi/hpsa.c | 45 ++++++++++++++++++++++- drivers/scsi/hpsa.h | 1 + 3 files changed, 61 insertions(+), 1 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-scsi_host b/Documentation/ABI/testing/sysfs-class-scsi_host index 29a4f89..0eb255e 100644 --- a/Documentation/ABI/testing/sysfs-class-scsi_host +++ b/Documentation/ABI/testing/sysfs-class-scsi_host @@ -11,3 +11,19 @@ Description: guaranteed. The 'isci_id' attribute unambiguously identifies the controller index: '0' for the first controller, '1' for the second. + +What: /sys/class/scsi_host/hostX/acciopath_status +Date: November 2013 +Contact: Stephen M. Cameron <scame...@beardog.cce.hp.com> +Description: This file contains the current status of the "SSD Smart Path" + feature of HP Smart Array RAID controllers using the hpsa + driver. SSD Smart Path, when enabled permits the driver to + send i/o requests directly to physical devices that are part + of a logical drive, bypassing the controllers firmware RAID + stack for a performance advantage when possible. A value of + '1' indicates the feature is enabled, and the controller may + use the direct i/o path to physical devices. A value of zero + means the feature is disabled and the controller may not use + the direct i/o path to physical devices. This setting is + controller wide, affecting all configured logical drives on the + controller. This file is readable and writable. diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 10f48ba..295c5da 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -287,6 +287,30 @@ static int check_for_busy(struct ctlr_info *h, struct CommandList *c) return 1; } +static ssize_t host_store_hp_ssd_smart_path_status(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int status, len; + struct ctlr_info *h; + struct Scsi_Host *shost = class_to_shost(dev); + char tmpbuf[10]; + + if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) + return -EACCES; + len = count > sizeof(tmpbuf) - 1 ? sizeof(tmpbuf) - 1 : count; + strncpy(tmpbuf, buf, len); + tmpbuf[len] = '\0'; + if (sscanf(tmpbuf, "%d", &status) != 1) + return -EINVAL; + h = shost_to_hba(shost); + h->acciopath_status = !!status; + dev_warn(&h->pdev->dev, + "hpsa: HP SSD Smart Path %s via sysfs update.\n", + h->acciopath_status ? "enabled" : "disabled"); + return count; +} + static ssize_t host_store_rescan(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -334,6 +358,17 @@ static ssize_t host_show_transport_mode(struct device *dev, "performant" : "simple"); } +static ssize_t host_show_hp_ssd_smart_path_status(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct ctlr_info *h; + struct Scsi_Host *shost = class_to_shost(dev); + + h = shost_to_hba(shost); + return snprintf(buf, 30, "HP SSD Smart Path %s\n", + (h->acciopath_status == 1) ? "enabled" : "disabled"); +} + /* List of controllers which cannot be hard reset on kexec with reset_devices */ static u32 unresettable_controller[] = { 0x324a103C, /* Smart Array P712m */ @@ -546,6 +581,9 @@ static DEVICE_ATTR(unique_id, S_IRUGO, unique_id_show, NULL); static DEVICE_ATTR(rescan, S_IWUSR, NULL, host_store_rescan); static DEVICE_ATTR(hp_ssd_smart_path_enabled, S_IRUGO, host_show_hp_ssd_smart_path_enabled, NULL); +static DEVICE_ATTR(hp_ssd_smart_path_status, S_IWUSR|S_IRUGO|S_IROTH, + host_show_hp_ssd_smart_path_status, + host_store_hp_ssd_smart_path_status); static DEVICE_ATTR(firmware_revision, S_IRUGO, host_show_firmware_revision, NULL); static DEVICE_ATTR(commands_outstanding, S_IRUGO, @@ -569,6 +607,7 @@ static struct device_attribute *hpsa_shost_attrs[] = { &dev_attr_commands_outstanding, &dev_attr_transport_mode, &dev_attr_resettable, + &dev_attr_hp_ssd_smart_path_status, NULL, }; @@ -3341,7 +3380,8 @@ static int hpsa_scsi_queue_command_lck(struct scsi_cmnd *cmd, * Retries always go down the normal I/O path. */ if (likely(cmd->retries == 0 && - cmd->request->cmd_type == REQ_TYPE_FS)) { + cmd->request->cmd_type == REQ_TYPE_FS && + h->acciopath_status)) { if (dev->offload_enabled) { rc = hpsa_scsi_ioaccel_raid_map(h, c); if (rc == 0) @@ -6323,6 +6363,9 @@ reinit_after_soft_reset: goto reinit_after_soft_reset; } + /* Enable Accelerated IO path at driver layer */ + h->acciopath_status = 1; + /* Turn the interrupts on so we can service requests */ h->access.set_intr_mask(h, HPSA_INTR_ON); diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h index 45bb1ea..1d3340d 100644 --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -181,6 +181,7 @@ struct ctlr_info { #define HPSATMF_LOG_QRY_TSET (1 << 24) #define HPSATMF_LOG_QRY_ASYNC (1 << 25) u32 events; + int acciopath_status; }; #define HPSA_ABORT_MSG 0 #define HPSA_DEVICE_RESET_MSG 1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html