linux/include/scsi/libsas.h
Jeff Garzik f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00

675 lines
17 KiB
C

/*
* SAS host prototypes and structures header file
*
* Copyright (C) 2005 Adaptec, Inc. All rights reserved.
* Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
*
* This file is licensed under GPLv2.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
*/
#ifndef _LIBSAS_H_
#define _LIBSAS_H_
#include <linux/timer.h>
#include <linux/pci.h>
#include <scsi/sas.h>
#include <linux/libata.h>
#include <linux/list.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_transport_sas.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
struct block_device;
enum sas_class {
SAS,
EXPANDER
};
enum sas_phy_role {
PHY_ROLE_NONE = 0,
PHY_ROLE_TARGET = 0x40,
PHY_ROLE_INITIATOR = 0x80,
};
enum sas_phy_type {
PHY_TYPE_PHYSICAL,
PHY_TYPE_VIRTUAL
};
/* The events are mnemonically described in sas_dump.c
* so when updating/adding events here, please also
* update the other file too.
*/
enum ha_event {
HAE_RESET = 0U,
HA_NUM_EVENTS = 1,
};
enum port_event {
PORTE_BYTES_DMAED = 0U,
PORTE_BROADCAST_RCVD = 1,
PORTE_LINK_RESET_ERR = 2,
PORTE_TIMER_EVENT = 3,
PORTE_HARD_RESET = 4,
PORT_NUM_EVENTS = 5,
};
enum phy_event {
PHYE_LOSS_OF_SIGNAL = 0U,
PHYE_OOB_DONE = 1,
PHYE_OOB_ERROR = 2,
PHYE_SPINUP_HOLD = 3, /* hot plug SATA, no COMWAKE sent */
PHY_NUM_EVENTS = 4,
};
enum discover_event {
DISCE_DISCOVER_DOMAIN = 0U,
DISCE_REVALIDATE_DOMAIN = 1,
DISCE_PORT_GONE = 2,
DISC_NUM_EVENTS = 3,
};
/* ---------- Expander Devices ---------- */
#define to_dom_device(_obj) container_of(_obj, struct domain_device, dev_obj)
#define to_dev_attr(_attr) container_of(_attr, struct domain_dev_attribute,\
attr)
enum routing_attribute {
DIRECT_ROUTING,
SUBTRACTIVE_ROUTING,
TABLE_ROUTING,
};
enum ex_phy_state {
PHY_EMPTY,
PHY_VACANT,
PHY_NOT_PRESENT,
PHY_DEVICE_DISCOVERED
};
struct ex_phy {
int phy_id;
enum ex_phy_state phy_state;
enum sas_dev_type attached_dev_type;
enum sas_linkrate linkrate;
u8 attached_sata_host:1;
u8 attached_sata_dev:1;
u8 attached_sata_ps:1;
enum sas_protocol attached_tproto;
enum sas_protocol attached_iproto;
u8 attached_sas_addr[SAS_ADDR_SIZE];
u8 attached_phy_id;
u8 phy_change_count;
enum routing_attribute routing_attr;
u8 virtual:1;
int last_da_index;
struct sas_phy *phy;
struct sas_port *port;
};
struct expander_device {
struct list_head children;
u16 ex_change_count;
u16 max_route_indexes;
u8 num_phys;
u8 configuring:1;
u8 conf_route_table:1;
u8 enclosure_logical_id[8];
struct ex_phy *ex_phy;
struct sas_port *parent_port;
};
/* ---------- SATA device ---------- */
enum ata_command_set {
ATA_COMMAND_SET = 0,
ATAPI_COMMAND_SET = 1,
};
struct sata_device {
enum ata_command_set command_set;
struct smp_resp rps_resp; /* report_phy_sata_resp */
__le16 *identify_device;
__le16 *identify_packet_device;
u8 port_no; /* port number, if this is a PM (Port) */
struct list_head children; /* PM Ports if this is a PM */
struct ata_port *ap;
struct ata_host ata_host;
struct ata_taskfile tf;
u32 sstatus;
u32 serror;
u32 scontrol;
};
/* ---------- Domain device ---------- */
struct domain_device {
enum sas_dev_type dev_type;
enum sas_linkrate linkrate;
enum sas_linkrate min_linkrate;
enum sas_linkrate max_linkrate;
int pathways;
struct domain_device *parent;
struct list_head siblings; /* devices on the same level */
struct asd_sas_port *port; /* shortcut to root of the tree */
struct list_head dev_list_node;
enum sas_protocol iproto;
enum sas_protocol tproto;
struct sas_rphy *rphy;
u8 sas_addr[SAS_ADDR_SIZE];
u8 hashed_sas_addr[HASHED_SAS_ADDR_SIZE];
u8 frame_rcvd[32];
union {
struct expander_device ex_dev;
struct sata_device sata_dev; /* STP & directly attached */
};
void *lldd_dev;
int gone;
};
struct sas_discovery_event {
struct work_struct work;
struct asd_sas_port *port;
};
struct sas_discovery {
spinlock_t disc_event_lock;
struct sas_discovery_event disc_work[DISC_NUM_EVENTS];
unsigned long pending;
u8 fanout_sas_addr[8];
u8 eeds_a[8];
u8 eeds_b[8];
int max_level;
};
/* The port struct is Class:RW, driver:RO */
struct asd_sas_port {
/* private: */
struct completion port_gone_completion;
struct sas_discovery disc;
struct domain_device *port_dev;
spinlock_t dev_list_lock;
struct list_head dev_list;
enum sas_linkrate linkrate;
struct sas_phy *phy;
struct work_struct work;
/* public: */
int id;
enum sas_class class;
u8 sas_addr[SAS_ADDR_SIZE];
u8 attached_sas_addr[SAS_ADDR_SIZE];
enum sas_protocol iproto;
enum sas_protocol tproto;
enum sas_oob_mode oob_mode;
spinlock_t phy_list_lock;
struct list_head phy_list;
int num_phys;
u32 phy_mask;
struct sas_ha_struct *ha;
struct sas_port *port;
void *lldd_port; /* not touched by the sas class code */
};
struct asd_sas_event {
struct work_struct work;
struct asd_sas_phy *phy;
};
/* The phy pretty much is controlled by the LLDD.
* The class only reads those fields.
*/
struct asd_sas_phy {
/* private: */
/* protected by ha->event_lock */
struct asd_sas_event port_events[PORT_NUM_EVENTS];
struct asd_sas_event phy_events[PHY_NUM_EVENTS];
unsigned long port_events_pending;
unsigned long phy_events_pending;
int error;
struct sas_phy *phy;
/* public: */
/* The following are class:RO, driver:R/W */
int enabled; /* must be set */
int id; /* must be set */
enum sas_class class;
enum sas_protocol iproto;
enum sas_protocol tproto;
enum sas_phy_type type;
enum sas_phy_role role;
enum sas_oob_mode oob_mode;
enum sas_linkrate linkrate;
u8 *sas_addr; /* must be set */
u8 attached_sas_addr[SAS_ADDR_SIZE]; /* class:RO, driver: R/W */
spinlock_t frame_rcvd_lock;
u8 *frame_rcvd; /* must be set */
int frame_rcvd_size;
spinlock_t sas_prim_lock;
u32 sas_prim;
struct list_head port_phy_el; /* driver:RO */
struct asd_sas_port *port; /* Class:RW, driver: RO */
struct sas_ha_struct *ha; /* may be set; the class sets it anyway */
void *lldd_phy; /* not touched by the sas_class_code */
};
struct scsi_core {
struct Scsi_Host *shost;
spinlock_t task_queue_lock;
struct list_head task_queue;
int task_queue_size;
struct task_struct *queue_thread;
};
struct sas_ha_event {
struct work_struct work;
struct sas_ha_struct *ha;
};
enum sas_ha_state {
SAS_HA_REGISTERED,
SAS_HA_UNREGISTERED
};
struct sas_ha_struct {
/* private: */
spinlock_t event_lock;
struct sas_ha_event ha_events[HA_NUM_EVENTS];
unsigned long pending;
enum sas_ha_state state;
spinlock_t state_lock;
struct scsi_core core;
/* public: */
char *sas_ha_name;
struct device *dev; /* should be set */
struct module *lldd_module; /* should be set */
u8 *sas_addr; /* must be set */
u8 hashed_sas_addr[HASHED_SAS_ADDR_SIZE];
spinlock_t phy_port_lock;
struct asd_sas_phy **sas_phy; /* array of valid pointers, must be set */
struct asd_sas_port **sas_port; /* array of valid pointers, must be set */
int num_phys; /* must be set, gt 0, static */
/* The class calls this to send a task for execution. */
int lldd_max_execute_num;
int lldd_queue_size;
/* LLDD calls these to notify the class of an event. */
void (*notify_ha_event)(struct sas_ha_struct *, enum ha_event);
void (*notify_port_event)(struct asd_sas_phy *, enum port_event);
void (*notify_phy_event)(struct asd_sas_phy *, enum phy_event);
void *lldd_ha; /* not touched by sas class code */
struct list_head eh_done_q;
};
#define SHOST_TO_SAS_HA(_shost) (*(struct sas_ha_struct **)(_shost)->hostdata)
static inline struct domain_device *
starget_to_domain_dev(struct scsi_target *starget) {
return starget->hostdata;
}
static inline struct domain_device *
sdev_to_domain_dev(struct scsi_device *sdev) {
return starget_to_domain_dev(sdev->sdev_target);
}
static inline struct domain_device *
cmd_to_domain_dev(struct scsi_cmnd *cmd)
{
return sdev_to_domain_dev(cmd->device);
}
void sas_hash_addr(u8 *hashed, const u8 *sas_addr);
/* Before calling a notify event, LLDD should use this function
* when the link is severed (possibly from its tasklet).
* The idea is that the Class only reads those, while the LLDD,
* can R/W these (thus avoiding a race).
*/
static inline void sas_phy_disconnected(struct asd_sas_phy *phy)
{
phy->oob_mode = OOB_NOT_CONNECTED;
phy->linkrate = SAS_LINK_RATE_UNKNOWN;
}
/* ---------- Tasks ---------- */
/*
service_response | SAS_TASK_COMPLETE | SAS_TASK_UNDELIVERED |
exec_status | | |
---------------------+---------------------+-----------------------+
SAM_... | X | |
DEV_NO_RESPONSE | X | X |
INTERRUPTED | X | |
QUEUE_FULL | | X |
DEVICE_UNKNOWN | | X |
SG_ERR | | X |
---------------------+---------------------+-----------------------+
*/
enum service_response {
SAS_TASK_COMPLETE,
SAS_TASK_UNDELIVERED = -1,
};
enum exec_status {
/* The SAM_STAT_.. codes fit in the lower 6 bits */
SAS_DEV_NO_RESPONSE = 0x80,
SAS_DATA_UNDERRUN,
SAS_DATA_OVERRUN,
SAS_INTERRUPTED,
SAS_QUEUE_FULL,
SAS_DEVICE_UNKNOWN,
SAS_SG_ERR,
SAS_OPEN_REJECT,
SAS_OPEN_TO,
SAS_PROTO_RESPONSE,
SAS_PHY_DOWN,
SAS_NAK_R_ERR,
SAS_PENDING,
SAS_ABORTED_TASK,
};
/* When a task finishes with a response, the LLDD examines the
* response:
* - For an ATA task task_status_struct::stat is set to
* SAS_PROTO_RESPONSE, and the task_status_struct::buf is set to the
* contents of struct ata_task_resp.
* - For SSP tasks, if no data is present or status/TMF response
* is valid, task_status_struct::stat is set. If data is present
* (SENSE data), the LLDD copies up to SAS_STATUS_BUF_SIZE, sets
* task_status_struct::buf_valid_size, and task_status_struct::stat is
* set to SAM_CHECK_COND.
*
* "buf" has format SCSI Sense for SSP task, or struct ata_task_resp
* for ATA task.
*
* "frame_len" is the total frame length, which could be more or less
* than actually copied.
*
* Tasks ending with response, always set the residual field.
*/
struct ata_task_resp {
u16 frame_len;
u8 ending_fis[24]; /* dev to host or data-in */
u32 sstatus;
u32 serror;
u32 scontrol;
u32 sactive;
};
#define SAS_STATUS_BUF_SIZE 96
struct task_status_struct {
enum service_response resp;
enum exec_status stat;
int buf_valid_size;
u8 buf[SAS_STATUS_BUF_SIZE];
u32 residual;
enum sas_open_rej_reason open_rej_reason;
};
/* ATA and ATAPI task queuable to a SAS LLDD.
*/
struct sas_ata_task {
struct host_to_dev_fis fis;
u8 atapi_packet[16]; /* 0 if not ATAPI task */
u8 retry_count; /* hardware retry, should be > 0 */
u8 dma_xfer:1; /* PIO:0 or DMA:1 */
u8 use_ncq:1;
u8 set_affil_pol:1;
u8 stp_affil_pol:1;
u8 device_control_reg_update:1;
};
struct sas_smp_task {
struct scatterlist smp_req;
struct scatterlist smp_resp;
};
enum task_attribute {
TASK_ATTR_SIMPLE = 0,
TASK_ATTR_HOQ = 1,
TASK_ATTR_ORDERED= 2,
TASK_ATTR_ACA = 4,
};
struct sas_ssp_task {
u8 retry_count; /* hardware retry, should be > 0 */
u8 LUN[8];
u8 enable_first_burst:1;
enum task_attribute task_attr;
u8 task_prio;
u8 cdb[16];
};
struct sas_task {
struct domain_device *dev;
struct list_head list;
spinlock_t task_state_lock;
unsigned task_state_flags;
enum sas_protocol task_proto;
/* Used by the discovery code. */
struct timer_list timer;
struct completion completion;
union {
struct sas_ata_task ata_task;
struct sas_smp_task smp_task;
struct sas_ssp_task ssp_task;
};
struct scatterlist *scatter;
int num_scatter;
u32 total_xfer_len;
u8 data_dir:2; /* Use PCI_DMA_... */
struct task_status_struct task_status;
void (*task_done)(struct sas_task *);
void *lldd_task; /* for use by LLDDs */
void *uldd_task;
struct work_struct abort_work;
};
extern struct kmem_cache *sas_task_cache;
#define SAS_TASK_STATE_PENDING 1
#define SAS_TASK_STATE_DONE 2
#define SAS_TASK_STATE_ABORTED 4
#define SAS_TASK_NEED_DEV_RESET 8
#define SAS_TASK_AT_INITIATOR 16
static inline struct sas_task *sas_alloc_task(gfp_t flags)
{
struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
if (task) {
INIT_LIST_HEAD(&task->list);
spin_lock_init(&task->task_state_lock);
task->task_state_flags = SAS_TASK_STATE_PENDING;
init_timer(&task->timer);
init_completion(&task->completion);
}
return task;
}
static inline void sas_free_task(struct sas_task *task)
{
if (task) {
BUG_ON(!list_empty(&task->list));
kmem_cache_free(sas_task_cache, task);
}
}
struct sas_domain_function_template {
/* The class calls these to notify the LLDD of an event. */
void (*lldd_port_formed)(struct asd_sas_phy *);
void (*lldd_port_deformed)(struct asd_sas_phy *);
/* The class calls these when a device is found or gone. */
int (*lldd_dev_found)(struct domain_device *);
void (*lldd_dev_gone)(struct domain_device *);
int (*lldd_execute_task)(struct sas_task *, int num,
gfp_t gfp_flags);
/* Task Management Functions. Must be called from process context. */
int (*lldd_abort_task)(struct sas_task *);
int (*lldd_abort_task_set)(struct domain_device *, u8 *lun);
int (*lldd_clear_aca)(struct domain_device *, u8 *lun);
int (*lldd_clear_task_set)(struct domain_device *, u8 *lun);
int (*lldd_I_T_nexus_reset)(struct domain_device *);
int (*lldd_lu_reset)(struct domain_device *, u8 *lun);
int (*lldd_query_task)(struct sas_task *);
/* Port and Adapter management */
int (*lldd_clear_nexus_port)(struct asd_sas_port *);
int (*lldd_clear_nexus_ha)(struct sas_ha_struct *);
/* Phy management */
int (*lldd_control_phy)(struct asd_sas_phy *, enum phy_func, void *);
};
extern int sas_register_ha(struct sas_ha_struct *);
extern int sas_unregister_ha(struct sas_ha_struct *);
int sas_set_phy_speed(struct sas_phy *phy,
struct sas_phy_linkrates *rates);
int sas_phy_enable(struct sas_phy *phy, int enabled);
int sas_phy_reset(struct sas_phy *phy, int hard_reset);
int sas_queue_up(struct sas_task *task);
extern int sas_queuecommand(struct Scsi_Host * ,struct scsi_cmnd *);
extern int sas_target_alloc(struct scsi_target *);
extern int sas_slave_alloc(struct scsi_device *);
extern int sas_slave_configure(struct scsi_device *);
extern void sas_slave_destroy(struct scsi_device *);
extern int sas_change_queue_depth(struct scsi_device *, int new_depth,
int reason);
extern int sas_change_queue_type(struct scsi_device *, int qt);
extern int sas_bios_param(struct scsi_device *,
struct block_device *,
sector_t capacity, int *hsc);
extern struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *);
extern void sas_domain_release_transport(struct scsi_transport_template *);
int sas_discover_root_expander(struct domain_device *);
void sas_init_ex_attr(void);
int sas_ex_revalidate_domain(struct domain_device *);
void sas_unregister_domain_devices(struct asd_sas_port *port);
void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *);
int sas_discover_event(struct asd_sas_port *, enum discover_event ev);
int sas_discover_sata(struct domain_device *);
int sas_discover_end_dev(struct domain_device *);
void sas_unregister_dev(struct domain_device *);
void sas_init_dev(struct domain_device *);
void sas_task_abort(struct sas_task *);
int __sas_task_abort(struct sas_task *);
int sas_eh_device_reset_handler(struct scsi_cmnd *cmd);
int sas_eh_bus_reset_handler(struct scsi_cmnd *cmd);
extern void sas_target_destroy(struct scsi_target *);
extern int sas_slave_alloc(struct scsi_device *);
extern int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg);
extern int sas_smp_handler(struct Scsi_Host *shost, struct sas_rphy *rphy,
struct request *req);
extern void sas_ssp_task_response(struct device *dev, struct sas_task *task,
struct ssp_response_iu *iu);
struct sas_phy *sas_find_local_phy(struct domain_device *dev);
int sas_request_addr(struct Scsi_Host *shost, u8 *addr);
#endif /* _SASLIB_H_ */