hpsa: honor queue depth of physical devices

When using the ioaccel submission methods, requests destined for RAID volumes
are sometimes diverted to physical devices.  The OS has no or limited
knowledge of these physical devices, so it is up to the driver to avoid
pushing the device too hard.  It is better to honor the physical device queue
limit rather than making the device spew zillions of TASK SET FULL responses.

This is so that hpsa based devices support /sys/block/sdNN/device/queue_type
of simple, which lets the SCSI midlayer automatically adjust the queue_depth
based on TASK SET FULL and GOOD status.

Adjust the queue depth for a new device after it is created based on the
maximum queue depths of the physical devices that constitute the
device. This drops the maximum queue depth from .can_queue of 1024 to
something like 174 for single-drive RAID-0, 348 for two-drive RAID-1, etc.
It also adjusts for the ratio of data to parity drives.
Reviewed-by: Scott Teel <scott.teel@pmcs.com>
Signed-off-by: Webb Scales <webbnh@hp.com>
Signed-off-by: Don Brace <don.brace@pmcs.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/hpsa.h

@@ -46,6 +46,11 @@ struct hpsa_scsi_dev_t {
 	unsigned char model[16];        /* bytes 16-31 of inquiry data */
 	unsigned char raid_level;	/* from inquiry page 0xC1 */
 	unsigned char volume_offline;	/* discovered via TUR or VPD */
+	u16 queue_depth;		/* max queue_depth for this device */
+	atomic_t ioaccel_cmds_out;	/* Only used for physical devices
+					 * counts commands sent to physical
+					 * device via "ioaccel" path.
+					 */
 	u32 ioaccel_handle;
 	int offload_config;		/* I/O accel RAID offload configured */
 	int offload_enabled;		/* I/O accel RAID offload enabled */
@@ -54,6 +59,15 @@ struct hpsa_scsi_dev_t {
 					 */
 	struct raid_map_data raid_map;	/* I/O accelerator RAID map */
 
+	/*
+	 * Pointers from logical drive map indices to the phys drives that
+	 * make those logical drives.  Note, multiple logical drives may
+	 * share physical drives.  You can have for instance 5 physical
+	 * drives with 3 logical drives each using those same 5 physical
+	 * disks. We need these pointers for counting i/o's out to physical
+	 * devices in order to honor physical device queue depth limits.
+	 */
+	struct hpsa_scsi_dev_t *phys_disk[RAID_MAP_MAX_ENTRIES];
 };
 
 struct reply_queue_buffer {

drivers/scsi/hpsa_cmd.h

@@ -240,6 +240,10 @@ struct ReportLUNdata {
 
 struct ext_report_lun_entry {
 	u8 lunid[8];
+#define GET_BMIC_BUS(lunid) ((lunid)[7] & 0x3F)
+#define GET_BMIC_LEVEL_TWO_TARGET(lunid) ((lunid)[6])
+#define GET_BMIC_DRIVE_NUMBER(lunid) (((GET_BMIC_BUS((lunid)) - 1) << 8) + \
+			GET_BMIC_LEVEL_TWO_TARGET((lunid)))
 	u8 wwid[8];
 	u8 device_type;
 	u8 device_flags;
@@ -268,6 +272,7 @@ struct SenseSubsystem_info {
 #define HPSA_CACHE_FLUSH 0x01	/* C2 was already being used by HPSA */
 #define BMIC_FLASH_FIRMWARE 0xF7
 #define BMIC_SENSE_CONTROLLER_PARAMETERS 0x64
+#define BMIC_IDENTIFY_PHYSICAL_DEVICE 0x15
 
 /* Command List Structure */
 union SCSI3Addr {
@@ -405,6 +410,17 @@ struct CommandList {
 	struct completion *waiting;
 	void   *scsi_cmd;
 	struct work_struct work;
+
+	/*
+	 * For commands using either of the two "ioaccel" paths to
+	 * bypass the RAID stack and go directly to the physical disk
+	 * phys_disk is a pointer to the hpsa_scsi_dev_t to which the
+	 * i/o is destined.  We need to store that here because the command
+	 * may potentially encounter TASK SET FULL and need to be resubmitted
+	 * For "normal" i/o's not using the "ioaccel" paths, phys_disk is
+	 * not used.
+	 */
+	struct hpsa_scsi_dev_t *phys_disk;
 } __aligned(COMMANDLIST_ALIGNMENT);
 
 /* Max S/G elements in I/O accelerator command */
@@ -641,5 +657,137 @@ struct hpsa_pci_info {
 	u32		board_id;
 };
 
+struct bmic_identify_physical_device {
+	u8    scsi_bus;          /* SCSI Bus number on controller */
+	u8    scsi_id;           /* SCSI ID on this bus */
+	__le16 block_size;	     /* sector size in bytes */
+	__le32 total_blocks;	     /* number for sectors on drive */
+	__le32 reserved_blocks;   /* controller reserved (RIS) */
+	u8    model[40];         /* Physical Drive Model */
+	u8    serial_number[40]; /* Drive Serial Number */
+	u8    firmware_revision[8]; /* drive firmware revision */
+	u8    scsi_inquiry_bits; /* inquiry byte 7 bits */
+	u8    compaq_drive_stamp; /* 0 means drive not stamped */
+	u8    last_failure_reason;
+#define BMIC_LAST_FAILURE_TOO_SMALL_IN_LOAD_CONFIG		0x01
+#define BMIC_LAST_FAILURE_ERROR_ERASING_RIS			0x02
+#define BMIC_LAST_FAILURE_ERROR_SAVING_RIS			0x03
+#define BMIC_LAST_FAILURE_FAIL_DRIVE_COMMAND			0x04
+#define BMIC_LAST_FAILURE_MARK_BAD_FAILED			0x05
+#define BMIC_LAST_FAILURE_MARK_BAD_FAILED_IN_FINISH_REMAP	0x06
+#define BMIC_LAST_FAILURE_TIMEOUT				0x07
+#define BMIC_LAST_FAILURE_AUTOSENSE_FAILED			0x08
+#define BMIC_LAST_FAILURE_MEDIUM_ERROR_1			0x09
+#define BMIC_LAST_FAILURE_MEDIUM_ERROR_2			0x0a
+#define BMIC_LAST_FAILURE_NOT_READY_BAD_SENSE			0x0b
+#define BMIC_LAST_FAILURE_NOT_READY				0x0c
+#define BMIC_LAST_FAILURE_HARDWARE_ERROR			0x0d
+#define BMIC_LAST_FAILURE_ABORTED_COMMAND			0x0e
+#define BMIC_LAST_FAILURE_WRITE_PROTECTED			0x0f
+#define BMIC_LAST_FAILURE_SPIN_UP_FAILURE_IN_RECOVER		0x10
+#define BMIC_LAST_FAILURE_REBUILD_WRITE_ERROR			0x11
+#define BMIC_LAST_FAILURE_TOO_SMALL_IN_HOT_PLUG			0x12
+#define BMIC_LAST_FAILURE_BUS_RESET_RECOVERY_ABORTED		0x13
+#define BMIC_LAST_FAILURE_REMOVED_IN_HOT_PLUG			0x14
+#define BMIC_LAST_FAILURE_INIT_REQUEST_SENSE_FAILED		0x15
+#define BMIC_LAST_FAILURE_INIT_START_UNIT_FAILED		0x16
+#define BMIC_LAST_FAILURE_INQUIRY_FAILED			0x17
+#define BMIC_LAST_FAILURE_NON_DISK_DEVICE			0x18
+#define BMIC_LAST_FAILURE_READ_CAPACITY_FAILED			0x19
+#define BMIC_LAST_FAILURE_INVALID_BLOCK_SIZE			0x1a
+#define BMIC_LAST_FAILURE_HOT_PLUG_REQUEST_SENSE_FAILED		0x1b
+#define BMIC_LAST_FAILURE_HOT_PLUG_START_UNIT_FAILED		0x1c
+#define BMIC_LAST_FAILURE_WRITE_ERROR_AFTER_REMAP		0x1d
+#define BMIC_LAST_FAILURE_INIT_RESET_RECOVERY_ABORTED		0x1e
+#define BMIC_LAST_FAILURE_DEFERRED_WRITE_ERROR			0x1f
+#define BMIC_LAST_FAILURE_MISSING_IN_SAVE_RIS			0x20
+#define BMIC_LAST_FAILURE_WRONG_REPLACE				0x21
+#define BMIC_LAST_FAILURE_GDP_VPD_INQUIRY_FAILED		0x22
+#define BMIC_LAST_FAILURE_GDP_MODE_SENSE_FAILED			0x23
+#define BMIC_LAST_FAILURE_DRIVE_NOT_IN_48BIT_MODE		0x24
+#define BMIC_LAST_FAILURE_DRIVE_TYPE_MIX_IN_HOT_PLUG		0x25
+#define BMIC_LAST_FAILURE_DRIVE_TYPE_MIX_IN_LOAD_CFG		0x26
+#define BMIC_LAST_FAILURE_PROTOCOL_ADAPTER_FAILED		0x27
+#define BMIC_LAST_FAILURE_FAULTY_ID_BAY_EMPTY			0x28
+#define BMIC_LAST_FAILURE_FAULTY_ID_BAY_OCCUPIED		0x29
+#define BMIC_LAST_FAILURE_FAULTY_ID_INVALID_BAY			0x2a
+#define BMIC_LAST_FAILURE_WRITE_RETRIES_FAILED			0x2b
+
+#define BMIC_LAST_FAILURE_SMART_ERROR_REPORTED			0x37
+#define BMIC_LAST_FAILURE_PHY_RESET_FAILED			0x38
+#define BMIC_LAST_FAILURE_ONLY_ONE_CTLR_CAN_SEE_DRIVE		0x40
+#define BMIC_LAST_FAILURE_KC_VOLUME_FAILED			0x41
+#define BMIC_LAST_FAILURE_UNEXPECTED_REPLACEMENT		0x42
+#define BMIC_LAST_FAILURE_OFFLINE_ERASE				0x80
+#define BMIC_LAST_FAILURE_OFFLINE_TOO_SMALL			0x81
+#define BMIC_LAST_FAILURE_OFFLINE_DRIVE_TYPE_MIX		0x82
+#define BMIC_LAST_FAILURE_OFFLINE_ERASE_COMPLETE		0x83
+
+	u8     flags;
+	u8     more_flags;
+	u8     scsi_lun;          /* SCSI LUN for phys drive */
+	u8     yet_more_flags;
+	u8     even_more_flags;
+	__le32 spi_speed_rules;/* SPI Speed data:Ultra disable diagnose */
+	u8     phys_connector[2];         /* connector number on controller */
+	u8     phys_box_on_bus;  /* phys enclosure this drive resides */
+	u8     phys_bay_in_box;  /* phys drv bay this drive resides */
+	__le32 rpm;              /* Drive rotational speed in rpm */
+	u8     device_type;       /* type of drive */
+	u8     sata_version;     /* only valid when drive_type is SATA */
+	__le64 big_total_block_count;
+	__le64 ris_starting_lba;
+	__le32 ris_size;
+	u8     wwid[20];
+	u8     controller_phy_map[32];
+	__le16 phy_count;
+	u8     phy_connected_dev_type[256];
+	u8     phy_to_drive_bay_num[256];
+	__le16 phy_to_attached_dev_index[256];
+	u8     box_index;
+	u8     reserved;
+	__le16 extra_physical_drive_flags;
+#define BMIC_PHYS_DRIVE_SUPPORTS_GAS_GAUGE(idphydrv) \
+	(idphydrv->extra_physical_drive_flags & (1 << 10))
+	u8     negotiated_link_rate[256];
+	u8     phy_to_phy_map[256];
+	u8     redundant_path_present_map;
+	u8     redundant_path_failure_map;
+	u8     active_path_number;
+	__le16 alternate_paths_phys_connector[8];
+	u8     alternate_paths_phys_box_on_port[8];
+	u8     multi_lun_device_lun_count;
+	u8     minimum_good_fw_revision[8];
+	u8     unique_inquiry_bytes[20];
+	u8     current_temperature_degreesC;
+	u8     temperature_threshold_degreesC;
+	u8     max_temperature_degreesC;
+	u8     logical_blocks_per_phys_block_exp; /* phyblocksize = 512*2^exp */
+	__le16 current_queue_depth_limit;
+	u8     switch_name[10];
+	__le16 switch_port;
+	u8     alternate_paths_switch_name[40];
+	u8     alternate_paths_switch_port[8];
+	__le16 power_on_hours; /* valid only if gas gauge supported */
+	__le16 percent_endurance_used; /* valid only if gas gauge supported. */
+#define BMIC_PHYS_DRIVE_SSD_WEAROUT(idphydrv) \
+	((idphydrv->percent_endurance_used & 0x80) || \
+	 (idphydrv->percent_endurance_used > 10000))
+	u8     drive_authentication;
+#define BMIC_PHYS_DRIVE_AUTHENTICATED(idphydrv) \
+	(idphydrv->drive_authentication == 0x80)
+	u8     smart_carrier_authentication;
+#define BMIC_SMART_CARRIER_AUTHENTICATION_SUPPORTED(idphydrv) \
+	(idphydrv->smart_carrier_authentication != 0x0)
+#define BMIC_SMART_CARRIER_AUTHENTICATED(idphydrv) \
+	(idphydrv->smart_carrier_authentication == 0x01)
+	u8     smart_carrier_app_fw_version;
+	u8     smart_carrier_bootloader_fw_version;
+	u8     encryption_key_name[64];
+	__le32 misc_drive_flags;
+	__le16 dek_index;
+	u8     padding[112];
+};
+
 #pragma pack()
 #endif /* HPSA_CMD_H */