path: root/include/scsi/scsi_device.h

/* 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/blkdev.h>
#include <scsi/scsi.h>
#include <linux/atomic.h>

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 */

	atomic_t device_busy;		/* commands actually active on LLDD */
	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;
	unsigned char current_tag;	/* current tag */
	struct scsi_target      *sdev_target;   /* used only for single_lun */

	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 */

	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 char		access_state;
	struct mutex		state_mutex;
	enum scsi_device_state sdev_state;
	struct task_struct