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OpenCloudOS-Kernel/include/scsi/scsi_device.h

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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SCSI_SCSI_DEVICE_H
#define _SCSI_SCSI_DEVICE_H
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/blk-mq.h>
#include <scsi/scsi.h>
#include <linux/atomic.h>
#include <linux/sbitmap.h>
struct bsg_device;
struct device;
struct request_queue;
struct scsi_cmnd;
struct scsi_lun;
struct scsi_sense_hdr;
typedef __u64 __bitwise blist_flags_t;
#define SCSI_SENSE_BUFFERSIZE 96
struct scsi_mode_data {
__u32 length;
__u16 block_descriptor_length;
__u8 medium_type;
__u8 device_specific;
__u8 header_length;
__u8 longlba:1;
};
/*
* sdev state: If you alter this, you also need to alter scsi_sysfs.c
* (for the ascii descriptions) and the state model enforcer:
* scsi_lib:scsi_device_set_state().
*/
enum scsi_device_state {
SDEV_CREATED = 1, /* device created but not added to sysfs
* Only internal commands allowed (for inq) */
SDEV_RUNNING, /* device properly configured
* All commands allowed */
SDEV_CANCEL, /* beginning to delete device
* Only error handler commands allowed */
SDEV_DEL, /* device deleted
* no commands allowed */
SDEV_QUIESCE, /* Device quiescent. No block commands
* will be accepted, only specials (which
* originate in the mid-layer) */
SDEV_OFFLINE, /* Device offlined (by error handling or
* user request */
SDEV_TRANSPORT_OFFLINE, /* Offlined by transport class error handler */
SDEV_BLOCK, /* Device blocked by scsi lld. No
* scsi commands from user or midlayer
* should be issued to the scsi
* lld. */
SDEV_CREATED_BLOCK, /* same as above but for created devices */
};
enum scsi_scan_mode {
SCSI_SCAN_INITIAL = 0,
SCSI_SCAN_RESCAN,
SCSI_SCAN_MANUAL,
};
enum scsi_device_event {
SDEV_EVT_MEDIA_CHANGE = 1, /* media has changed */
SDEV_EVT_INQUIRY_CHANGE_REPORTED, /* 3F 03 UA reported */
SDEV_EVT_CAPACITY_CHANGE_REPORTED, /* 2A 09 UA reported */
SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED, /* 38 07 UA reported */
SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED, /* 2A 01 UA reported */
SDEV_EVT_LUN_CHANGE_REPORTED, /* 3F 0E UA reported */
SDEV_EVT_ALUA_STATE_CHANGE_REPORTED, /* 2A 06 UA reported */
SDEV_EVT_POWER_ON_RESET_OCCURRED, /* 29 00 UA reported */
SDEV_EVT_FIRST = SDEV_EVT_MEDIA_CHANGE,
SDEV_EVT_LAST = SDEV_EVT_POWER_ON_RESET_OCCURRED,
SDEV_EVT_MAXBITS = SDEV_EVT_LAST + 1
};
struct scsi_event {
enum scsi_device_event evt_type;
struct list_head node;
/* put union of data structures, for non-simple event types,
* here
*/
};
/**
* struct scsi_vpd - SCSI Vital Product Data
* @rcu: For kfree_rcu().
* @len: Length in bytes of @data.
* @data: VPD data as defined in various T10 SCSI standard documents.
*/
struct scsi_vpd {
struct rcu_head rcu;
int len;
unsigned char data[];
};
struct scsi_device {
struct Scsi_Host *host;
struct request_queue *request_queue;
/* the next two are protected by the host->host_lock */
struct list_head siblings; /* list of all devices on this host */
struct list_head same_target_siblings; /* just the devices sharing same target id */
struct sbitmap budget_map;
atomic_t device_blocked; /* Device returned QUEUE_FULL. */
atomic_t restarts;
spinlock_t list_lock;
struct list_head starved_entry;
unsigned short queue_depth; /* How deep of a queue we want */
unsigned short max_queue_depth; /* max queue depth */
unsigned short last_queue_full_depth; /* These two are used by */
unsigned short last_queue_full_count; /* scsi_track_queue_full() */
unsigned long last_queue_full_time; /* last queue full time */
unsigned long queue_ramp_up_period; /* ramp up period in jiffies */
#define SCSI_DEFAULT_RAMP_UP_PERIOD (120 * HZ)
unsigned long last_queue_ramp_up; /* last queue ramp up time */
unsigned int id, channel;
u64 lun;
unsigned int manufacturer; /* Manufacturer of device, for using
* vendor-specific cmd's */
unsigned sector_size; /* size in bytes */
void *hostdata; /* available to low-level driver */
unsigned char type;
char scsi_level;
char inq_periph_qual; /* PQ from INQUIRY data */
struct mutex inquiry_mutex;
unsigned char inquiry_len; /* valid bytes in 'inquiry' */
unsigned char * inquiry; /* INQUIRY response data */
const char * vendor; /* [back_compat] point into 'inquiry' ... */
const char * model; /* ... after scan; point to static string */
const char * rev; /* ... "nullnullnullnull" before scan */
#define SCSI_VPD_PG_LEN 255
struct scsi_vpd __rcu *vpd_pg0;
struct scsi_vpd __rcu *vpd_pg83;
struct scsi_vpd __rcu *vpd_pg80;
struct scsi_vpd __rcu *vpd_pg89;
struct scsi_target *sdev_target;
blist_flags_t sdev_bflags; /* black/white flags as also found in
* scsi_devinfo.[hc]. For now used only to
* pass settings from slave_alloc to scsi
* core. */
unsigned int eh_timeout; /* Error handling timeout */
unsigned removable:1;
unsigned changed:1; /* Data invalid due to media change */
unsigned busy:1; /* Used to prevent races */
unsigned lockable:1; /* Able to prevent media removal */
unsigned locked:1; /* Media removal disabled */
unsigned borken:1; /* Tell the Seagate driver to be
* painfully slow on this device */
unsigned disconnect:1; /* can disconnect */
unsigned soft_reset:1; /* Uses soft reset option */
unsigned sdtr:1; /* Device supports SDTR messages */
unsigned wdtr:1; /* Device supports WDTR messages */
unsigned ppr:1; /* Device supports PPR messages */
unsigned tagged_supported:1; /* Supports SCSI-II tagged queuing */
unsigned simple_tags:1; /* simple queue tag messages are enabled */
unsigned was_reset:1; /* There was a bus reset on the bus for
* this device */
unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
* because we did a bus reset. */
unsigned use_10_for_rw:1; /* first try 10-byte read / write */
unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
unsigned no_report_opcodes:1; /* no REPORT SUPPORTED OPERATION CODES */
unsigned no_write_same:1; /* no WRITE SAME command */
unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
unsigned skip_ms_page_8:1; /* do not use MODE SENSE page 0x08 */
unsigned skip_ms_page_3f:1; /* do not use MODE SENSE page 0x3f */
unsigned skip_vpd_pages:1; /* do not read VPD pages */
unsigned try_vpd_pages:1; /* attempt to read VPD pages */
unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
unsigned no_start_on_add:1; /* do not issue start on add */
unsigned allow_restart:1; /* issue START_UNIT in error handler */
unsigned manage_start_stop:1; /* Let HLD (sd) manage start/stop */
unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */
unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
unsigned select_no_atn:1;
unsigned fix_capacity:1; /* READ_CAPACITY is too high by 1 */
unsigned guess_capacity:1; /* READ_CAPACITY might be too high by 1 */
unsigned retry_hwerror:1; /* Retry HARDWARE_ERROR */
unsigned last_sector_bug:1; /* do not use multisector accesses on
SD_LAST_BUGGY_SECTORS */
unsigned no_read_disc_info:1; /* Avoid READ_DISC_INFO cmds */
unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
unsigned try_rc_10_first:1; /* Try READ_CAPACACITY_10 first */
unsigned security_supported:1; /* Supports Security Protocols */
unsigned is_visible:1; /* is the device visible in sysfs */
unsigned wce_default_on:1; /* Cache is ON by default */
unsigned no_dif:1; /* T10 PI (DIF) should be disabled */
unsigned broken_fua:1; /* Don't set FUA bit */
unsigned lun_in_cdb:1; /* Store LUN bits in CDB[1] */
unsigned unmap_limit_for_ws:1; /* Use the UNMAP limit for WRITE SAME */
unsigned rpm_autosuspend:1; /* Enable runtime autosuspend at device
* creation time */
unsigned ignore_media_change:1; /* Ignore MEDIA CHANGE on resume */
unsigned int queue_stopped; /* request queue is quiesced */
bool offline_already; /* Device offline message logged */
atomic_t disk_events_disable_depth; /* disable depth for disk events */
DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
struct list_head event_list; /* asserted events */
struct work_struct event_work;
unsigned int max_device_blocked; /* what device_blocked counts down from */
#define SCSI_DEFAULT_DEVICE_BLOCKED 3
atomic_t iorequest_cnt;
atomic_t iodone_cnt;
atomic_t ioerr_cnt;
struct device sdev_gendev,
sdev_dev;
struct execute_work ew; /* used to get process context on put */
struct work_struct requeue_work;
struct scsi_device_handler *handler;
void *handler_data;
size_t dma_drain_len;
void *dma_drain_buf;
unsigned int sg_timeout;
unsigned int sg_reserved_size;
struct bsg_device *bsg_dev;
unsigned char access_state;
struct mutex state_mutex;
enum scsi_device_state sdev_state;
struct task_struct *quiesced_by;
unsigned long sdev_data[];
} __attribute__((aligned(sizeof(unsigned long))));
#define to_scsi_device(d) \
container_of(d, struct scsi_device, sdev_gendev)
#define class_to_sdev(d) \
container_of(d, struct scsi_device, sdev_dev)
#define transport_class_to_sdev(class_dev) \
to_scsi_device(class_dev->parent)
#define sdev_dbg(sdev, fmt, a...) \
dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
/*
* like scmd_printk, but the device name is passed in
* as a string pointer
*/
__printf(4, 5) void
sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
const char *, ...);
#define sdev_printk(l, sdev, fmt, a...) \
sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
__printf(3, 4) void
scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
#define scmd_dbg(scmd, fmt, a...) \
do { \
struct request *__rq = scsi_cmd_to_rq((scmd)); \
\
if (__rq->rq_disk) \
sdev_dbg((scmd)->device, "[%s] " fmt, \
__rq->rq_disk->disk_name, ##a); \
else \
sdev_dbg((scmd)->device, fmt, ##a); \
} while (0)
enum scsi_target_state {
STARGET_CREATED = 1,
STARGET_RUNNING,
STARGET_REMOVE,
STARGET_CREATED_REMOVE,
STARGET_DEL,
};
/*
* scsi_target: representation of a scsi target, for now, this is only
* used for single_lun devices. If no one has active IO to the target,
* starget_sdev_user is NULL, else it points to the active sdev.
*/
struct scsi_target {
struct scsi_device *starget_sdev_user;
struct list_head siblings;
struct list_head devices;
struct device dev;
struct kref reap_ref; /* last put renders target invisible */
unsigned int channel;
unsigned int id; /* target id ... replace
* scsi_device.id eventually */
unsigned int create:1; /* signal that it needs to be added */
unsigned int single_lun:1; /* Indicates we should only
* allow I/O to one of the luns
* for the device at a time. */
unsigned int pdt_1f_for_no_lun:1; /* PDT = 0x1f
* means no lun present. */
unsigned int no_report_luns:1; /* Don't use
* REPORT LUNS for scanning. */
unsigned int expecting_lun_change:1; /* A device has reported
* a 3F/0E UA, other devices on
* the same target will also. */
/* commands actually active on LLD. */
atomic_t target_busy;
atomic_t target_blocked;
/*
* LLDs should set this in the slave_alloc host template callout.
* If set to zero then there is not limit.
*/
unsigned int can_queue;
unsigned int max_target_blocked;
#define SCSI_DEFAULT_TARGET_BLOCKED 3
char scsi_level;
enum scsi_target_state state;
void *hostdata; /* available to low-level driver */
unsigned long starget_data[]; /* for the transport */
/* starget_data must be the last element!!!! */
} __attribute__((aligned(sizeof(unsigned long))));
#define to_scsi_target(d) container_of(d, struct scsi_target, dev)
static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
{
return to_scsi_target(sdev->sdev_gendev.parent);
}
#define transport_class_to_starget(class_dev) \
to_scsi_target(class_dev->parent)
#define starget_printk(prefix, starget, fmt, a...) \
dev_printk(prefix, &(starget)->dev, fmt, ##a)
extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
uint, uint, u64, void *hostdata);
extern int scsi_add_device(struct Scsi_Host *host, uint channel,
uint target, u64 lun);
extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
extern void scsi_remove_device(struct scsi_device *);
extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
void scsi_attach_vpd(struct scsi_device *sdev);
extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
extern int __must_check scsi_device_get(struct scsi_device *);
extern void scsi_device_put(struct scsi_device *);
extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
uint, uint, u64);
extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
uint, uint, u64);
extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
u64);
extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
u64);
extern void starget_for_each_device(struct scsi_target *, void *,
void (*fn)(struct scsi_device *, void *));
extern void __starget_for_each_device(struct scsi_target *, void *,
void (*fn)(struct scsi_device *,
void *));
/* only exposed to implement shost_for_each_device */
extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
struct scsi_device *);
/**
* shost_for_each_device - iterate over all devices of a host
* @sdev: the &struct scsi_device to use as a cursor
* @shost: the &struct scsi_host to iterate over
*
* Iterator that returns each device attached to @shost. This loop
* takes a reference on each device and releases it at the end. If
* you break out of the loop, you must call scsi_device_put(sdev).
*/
#define shost_for_each_device(sdev, shost) \
for ((sdev) = __scsi_iterate_devices((shost), NULL); \
(sdev); \
(sdev) = __scsi_iterate_devices((shost), (sdev)))
/**
* __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
* @sdev: the &struct scsi_device to use as a cursor
* @shost: the &struct scsi_host to iterate over
*
* Iterator that returns each device attached to @shost. It does _not_
* take a reference on the scsi_device, so the whole loop must be
* protected by shost->host_lock.
*
* Note: The only reason to use this is because you need to access the
* device list in interrupt context. Otherwise you really want to use
* shost_for_each_device instead.
*/
#define __shost_for_each_device(sdev, shost) \
list_for_each_entry((sdev), &((shost)->__devices), siblings)
extern int scsi_change_queue_depth(struct scsi_device *, int);
extern int scsi_track_queue_full(struct scsi_device *, int);
extern int scsi_set_medium_removal(struct scsi_device *, char);
extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
unsigned char *buffer, int len, int timeout,
int retries, struct scsi_mode_data *data,
struct scsi_sense_hdr *);
extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
int modepage, unsigned char *buffer, int len,
int timeout, int retries,
struct scsi_mode_data *data,
struct scsi_sense_hdr *);
extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
int retries, struct scsi_sense_hdr *sshdr);
extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
int buf_len);
extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
unsigned int len, unsigned char opcode);
extern int scsi_device_set_state(struct scsi_device *sdev,
enum scsi_device_state state);
extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
gfp_t gfpflags);
extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
extern void sdev_evt_send_simple(struct scsi_device *sdev,
enum scsi_device_event evt_type, gfp_t gfpflags);
extern int scsi_device_quiesce(struct scsi_device *sdev);
extern void scsi_device_resume(struct scsi_device *sdev);
extern void scsi_target_quiesce(struct scsi_target *);
extern void scsi_target_resume(struct scsi_target *);
extern void scsi_scan_target(struct device *parent, unsigned int channel,
unsigned int id, u64 lun,
enum scsi_scan_mode rescan);
extern void scsi_target_reap(struct scsi_target *);
extern void scsi_target_block(struct device *);
extern void scsi_target_unblock(struct device *, enum scsi_device_state);
extern void scsi_remove_target(struct device *);
extern const char *scsi_device_state_name(enum scsi_device_state);
extern int scsi_is_sdev_device(const struct device *);
extern int scsi_is_target_device(const struct device *);
extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
extern int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
int data_direction, void *buffer, unsigned bufflen,
unsigned char *sense, struct scsi_sense_hdr *sshdr,
int timeout, int retries, u64 flags,
req_flags_t rq_flags, int *resid);
/* Make sure any sense buffer is the correct size. */
#define scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
sshdr, timeout, retries, flags, rq_flags, resid) \
({ \
BUILD_BUG_ON((sense) != NULL && \
sizeof(sense) != SCSI_SENSE_BUFFERSIZE); \
__scsi_execute(sdev, cmd, data_direction, buffer, bufflen, \
sense, sshdr, timeout, retries, flags, rq_flags, \
resid); \
})
static inline int scsi_execute_req(struct scsi_device *sdev,
const unsigned char *cmd, int data_direction, void *buffer,
unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
int retries, int *resid)
{
return scsi_execute(sdev, cmd, data_direction, buffer,
bufflen, NULL, sshdr, timeout, retries, 0, 0, resid);
}
extern void sdev_disable_disk_events(struct scsi_device *sdev);
extern void sdev_enable_disk_events(struct scsi_device *sdev);
extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
#ifdef CONFIG_PM
extern int scsi_autopm_get_device(struct scsi_device *);
extern void scsi_autopm_put_device(struct scsi_device *);
#else
static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
static inline void scsi_autopm_put_device(struct scsi_device *d) {}
#endif /* CONFIG_PM */
static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
{
return device_reprobe(&sdev->sdev_gendev);
}
static inline unsigned int sdev_channel(struct scsi_device *sdev)
{
return sdev->channel;
}
static inline unsigned int sdev_id(struct scsi_device *sdev)
{
return sdev->id;
}
#define scmd_id(scmd) sdev_id((scmd)->device)
#define scmd_channel(scmd) sdev_channel((scmd)->device)
/*
* checks for positions of the SCSI state machine
*/
static inline int scsi_device_online(struct scsi_device *sdev)
{
return (sdev->sdev_state != SDEV_OFFLINE &&
sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
sdev->sdev_state != SDEV_DEL);
}
static inline int scsi_device_blocked(struct scsi_device *sdev)
{
return sdev->sdev_state == SDEV_BLOCK ||
sdev->sdev_state == SDEV_CREATED_BLOCK;
}
static inline int scsi_device_created(struct scsi_device *sdev)
{
return sdev->sdev_state == SDEV_CREATED ||
sdev->sdev_state == SDEV_CREATED_BLOCK;
}
int scsi_internal_device_block_nowait(struct scsi_device *sdev);
int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
enum scsi_device_state new_state);
/* accessor functions for the SCSI parameters */
static inline int scsi_device_sync(struct scsi_device *sdev)
{
return sdev->sdtr;
}
static inline int scsi_device_wide(struct scsi_device *sdev)
{
return sdev->wdtr;
}
static inline int scsi_device_dt(struct scsi_device *sdev)
{
return sdev->ppr;
}
static inline int scsi_device_dt_only(struct scsi_device *sdev)
{
if (sdev->inquiry_len < 57)
return 0;
return (sdev->inquiry[56] & 0x0c) == 0x04;
}
static inline int scsi_device_ius(struct scsi_device *sdev)
{
if (sdev->inquiry_len < 57)
return 0;
return sdev->inquiry[56] & 0x01;
}
static inline int scsi_device_qas(struct scsi_device *sdev)
{
if (sdev->inquiry_len < 57)
return 0;
return sdev->inquiry[56] & 0x02;
}
static inline int scsi_device_enclosure(struct scsi_device *sdev)
{
return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
}
static inline int scsi_device_protection(struct scsi_device *sdev)
{
if (sdev->no_dif)
return 0;
return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
}
static inline int scsi_device_tpgs(struct scsi_device *sdev)
{
return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
}
/**
* scsi_device_supports_vpd - test if a device supports VPD pages
* @sdev: the &struct scsi_device to test
*
* If the 'try_vpd_pages' flag is set it takes precedence.
* Otherwise we will assume VPD pages are supported if the
* SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
*/
static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
{
/* Attempt VPD inquiry if the device blacklist explicitly calls
* for it.
*/
if (sdev->try_vpd_pages)
return 1;
/*
* Although VPD inquiries can go to SCSI-2 type devices,
* some USB ones crash on receiving them, and the pages
* we currently ask for are mandatory for SPC-2 and beyond
*/
if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
return 1;
return 0;
}
static inline int scsi_device_busy(struct scsi_device *sdev)
{
return sbitmap_weight(&sdev->budget_map);
}
#define MODULE_ALIAS_SCSI_DEVICE(type) \
MODULE_ALIAS("scsi:t-" __stringify(type) "*")
#define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
#endif /* _SCSI_SCSI_DEVICE_H */
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