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linux/include/scsi/scsi_host.h

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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SCSI_SCSI_HOST_H
#define _SCSI_SCSI_HOST_H
#include <linux/device.h>
#include <linux/list.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/seq_file.h>
#include <linux/blk-mq.h>
#include <scsi/scsi.h>
struct request_queue;
struct block_device;
struct completion;
struct module;
struct scsi_cmnd;
struct scsi_device;
struct scsi_host_cmd_pool;
struct scsi_target;
struct Scsi_Host;
struct scsi_host_cmd_pool;
struct scsi_transport_template;
struct blk_queue_tags;
/*
* The various choices mean:
* NONE: Self evident. Host adapter is not capable of scatter-gather.
* ALL: Means that the host adapter module can do scatter-gather,
* and that there is no limit to the size of the table to which
* we scatter/gather data. The value we set here is the maximum
* single element sglist. To use chained sglists, the adapter
* has to set a value beyond ALL (and correctly use the chain
* handling API.
* Anything else: Indicates the maximum number of chains that can be
* used in one scatter-gather request.
*/
#define SG_NONE 0
#define SG_ALL SG_CHUNK_SIZE
#define MODE_UNKNOWN 0x00
#define MODE_INITIATOR 0x01
#define MODE_TARGET 0x02
#define DISABLE_CLUSTERING 0
#define ENABLE_CLUSTERING 1
struct scsi_host_template {
struct module *module;
const char *name;
/*
* The info function will return whatever useful information the
* developer sees fit. If not provided, then the name field will
* be used instead.
*
* Status: OPTIONAL
*/
const char *(* info)(struct Scsi_Host *);
/*
* Ioctl interface
*
* Status: OPTIONAL
*/
int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
#ifdef CONFIG_COMPAT
/*
* Compat handler. Handle 32bit ABI.
* When unknown ioctl is passed return -ENOIOCTLCMD.
*
* Status: OPTIONAL
*/
int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
#endif
/*
* The queuecommand function is used to queue up a scsi
* command block to the LLDD. When the driver finished
* processing the command the done callback is invoked.
*
* If queuecommand returns 0, then the HBA has accepted the
* command. The done() function must be called on the command
* when the driver has finished with it. (you may call done on the
* command before queuecommand returns, but in this case you
* *must* return 0 from queuecommand).
*
* Queuecommand may also reject the command, in which case it may
* not touch the command and must not call done() for it.
*
* There are two possible rejection returns:
*
* SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
* allow commands to other devices serviced by this host.
*
* SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
* host temporarily.
*
* For compatibility, any other non-zero return is treated the
* same as SCSI_MLQUEUE_HOST_BUSY.
*
* NOTE: "temporarily" means either until the next command for#
* this device/host completes, or a period of time determined by
* I/O pressure in the system if there are no other outstanding
* commands.
*
* STATUS: REQUIRED
*/
int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
/*
* This is an error handling strategy routine. You don't need to
* define one of these if you don't want to - there is a default
* routine that is present that should work in most cases. For those
* driver authors that have the inclination and ability to write their
* own strategy routine, this is where it is specified. Note - the
* strategy routine is *ALWAYS* run in the context of the kernel eh
* thread. Thus you are guaranteed to *NOT* be in an interrupt
* handler when you execute this, and you are also guaranteed to
* *NOT* have any other commands being queued while you are in the
* strategy routine. When you return from this function, operations
* return to normal.
*
* See scsi_error.c scsi_unjam_host for additional comments about
* what this function should and should not be attempting to do.
*
* Status: REQUIRED (at least one of them)
*/
int (* eh_abort_handler)(struct scsi_cmnd *);
int (* eh_device_reset_handler)(struct scsi_cmnd *);
int (* eh_target_reset_handler)(struct scsi_cmnd *);
int (* eh_bus_reset_handler)(struct scsi_cmnd *);
int (* eh_host_reset_handler)(struct scsi_cmnd *);
/*
* Before the mid layer attempts to scan for a new device where none
* currently exists, it will call this entry in your driver. Should
* your driver need to allocate any structs or perform any other init
* items in order to send commands to a currently unused target/lun
* combo, then this is where you can perform those allocations. This
* is specifically so that drivers won't have to perform any kind of
* "is this a new device" checks in their queuecommand routine,
* thereby making the hot path a bit quicker.
*
* Return values: 0 on success, non-0 on failure
*
* Deallocation: If we didn't find any devices at this ID, you will
* get an immediate call to slave_destroy(). If we find something
* here then you will get a call to slave_configure(), then the
* device will be used for however long it is kept around, then when
* the device is removed from the system (or * possibly at reboot
* time), you will then get a call to slave_destroy(). This is
* assuming you implement slave_configure and slave_destroy.
* However, if you allocate memory and hang it off the device struct,
* then you must implement the slave_destroy() routine at a minimum
* in order to avoid leaking memory
* each time a device is tore down.
*
* Status: OPTIONAL
*/
int (* slave_alloc)(struct scsi_device *);
/*
* Once the device has responded to an INQUIRY and we know the
* device is online, we call into the low level driver with the
* struct scsi_device *. If the low level device driver implements
* this function, it *must* perform the task of setting the queue
* depth on the device. All other tasks are optional and depend
* on what the driver supports and various implementation details.
*
* Things currently recommended to be handled at this time include:
*
* 1. Setting the device queue depth. Proper setting of this is
* described in the comments for scsi_change_queue_depth.
* 2. Determining if the device supports the various synchronous
* negotiation protocols. The device struct will already have
* responded to INQUIRY and the results of the standard items
* will have been shoved into the various device flag bits, eg.
* device->sdtr will be true if the device supports SDTR messages.
* 3. Allocating command structs that the device will need.
* 4. Setting the default timeout on this device (if needed).
* 5. Anything else the low level driver might want to do on a device
* specific setup basis...
* 6. Return 0 on success, non-0 on error. The device will be marked
* as offline on error so that no access will occur. If you return
* non-0, your slave_destroy routine will never get called for this
* device, so don't leave any loose memory hanging around, clean
* up after yourself before returning non-0
*
* Status: OPTIONAL
*/
int (* slave_configure)(struct scsi_device *);
/*
* Immediately prior to deallocating the device and after all activity
* has ceased the mid layer calls this point so that the low level
* driver may completely detach itself from the scsi device and vice
* versa. The low level driver is responsible for freeing any memory
* it allocated in the slave_alloc or slave_configure calls.
*
* Status: OPTIONAL
*/
void (* slave_destroy)(struct scsi_device *);
/*
* Before the mid layer attempts to scan for a new device attached
* to a target where no target currently exists, it will call this
* entry in your driver. Should your driver need to allocate any
* structs or perform any other init items in order to send commands
* to a currently unused target, then this is where you can perform
* those allocations.
*
* Return values: 0 on success, non-0 on failure
*
* Status: OPTIONAL
*/
int (* target_alloc)(struct scsi_target *);
/*
* Immediately prior to deallocating the target structure, and
* after all activity to attached scsi devices has ceased, the
* midlayer calls this point so that the driver may deallocate
* and terminate any references to the target.
*
* Status: OPTIONAL
*/
void (* target_destroy)(struct scsi_target *);
/*
* If a host has the ability to discover targets on its own instead
* of scanning the entire bus, it can fill in this function and
* call scsi_scan_host(). This function will be called periodically
* until it returns 1 with the scsi_host and the elapsed time of
* the scan in jiffies.
*
* Status: OPTIONAL
*/
int (* scan_finished)(struct Scsi_Host *, unsigned long);
/*
* If the host wants to be called before the scan starts, but
* after the midlayer has set up ready for the scan, it can fill
* in this function.
*
* Status: OPTIONAL
*/
void (* scan_start)(struct Scsi_Host *);
/*
* Fill in this function to allow the queue depth of this host
* to be changeable (on a per device basis). Returns either
* the current queue depth setting (may be different from what
* was passed in) or an error. An error should only be
* returned if the requested depth is legal but the driver was
* unable to set it. If the requested depth is illegal, the
* driver should set and return the closest legal queue depth.
*
* Status: OPTIONAL
*/
int (* change_queue_depth)(struct scsi_device *, int);
/*
* This functions lets the driver expose the queue mapping
* to the block layer.
*
* Status: OPTIONAL
*/
int (* map_queues)(struct Scsi_Host *shost);
/*
* This function determines the BIOS parameters for a given
* harddisk. These tend to be numbers that are made up by
* the host adapter. Parameters:
* size, device, list (heads, sectors, cylinders)
*
* Status: OPTIONAL
*/
int (* bios_param)(struct scsi_device *, struct block_device *,
sector_t, int []);
/*
* This function is called when one or more partitions on the
* device reach beyond the end of the device.
*
* Status: OPTIONAL
*/
void (*unlock_native_capacity)(struct scsi_device *);
/*
* Can be used to export driver statistics and other infos to the
* world outside the kernel ie. userspace and it also provides an
* interface to feed the driver with information.
*
* Status: OBSOLETE
*/
int (*show_info)(struct seq_file *, struct Scsi_Host *);
int (*write_info)(struct Scsi_Host *, char *, int);
/*
* This is an optional routine that allows the transport to become
* involved when a scsi io timer fires. The return value tells the
* timer routine how to finish the io timeout handling:
* EH_HANDLED: I fixed the error, please complete the command
* EH_RESET_TIMER: I need more time, reset the timer and
* begin counting again
* EH_DONE: Begin normal error recovery
*
* Status: OPTIONAL
*/
enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
/* This is an optional routine that allows transport to initiate
* LLD adapter or firmware reset using sysfs attribute.
*
* Return values: 0 on success, -ve value on failure.
*
* Status: OPTIONAL
*/
int (*host_reset)(struct Scsi_Host *shost, int reset_type);
#define SCSI_ADAPTER_RESET 1
#define SCSI_FIRMWARE_RESET 2
/*
* Name of proc directory
*/
const char *proc_name;
/*
* Used to store the procfs directory if a driver implements the
* show_info method.
*/
struct proc_dir_entry *proc_dir;
/*
* This determines if we will use a non-interrupt driven
* or an interrupt driven scheme. It is set to the maximum number
* of simultaneous commands a given host adapter will accept.
*/
int can_queue;
/*
* In many instances, especially where disconnect / reconnect are
* supported, our host also has an ID on the SCSI bus. If this is
* the case, then it must be reserved. Please set this_id to -1 if
* your setup is in single initiator mode, and the host lacks an
* ID.
*/
int this_id;
/*
* This determines the degree to which the host adapter is capable
* of scatter-gather.
*/
unsigned short sg_tablesize;
unsigned short sg_prot_tablesize;
/*
* Set this if the host adapter has limitations beside segment count.
*/
unsigned int max_sectors;
/*
* DMA scatter gather segment boundary limit. A segment crossing this
* boundary will be split in two.
*/
unsigned long dma_boundary;
/*
* This specifies "machine infinity" for host templates which don't
* limit the transfer size. Note this limit represents an absolute
* maximum, and may be over the transfer limits allowed for
* individual devices (e.g. 256 for SCSI-1).
*/
#define SCSI_DEFAULT_MAX_SECTORS 1024
/*
* True if this host adapter can make good use of linked commands.
* This will allow more than one command to be queued to a given
* unit on a given host. Set this to the maximum number of command
* blocks to be provided for each device. Set this to 1 for one
* command block per lun, 2 for two, etc. Do not set this to 0.
* You should make sure that the host adapter will do the right thing
* before you try setting this above 1.
*/
short cmd_per_lun;
/*
* present contains counter indicating how many boards of this
* type were found when we did the scan.
*/
unsigned char present;
/* If use block layer to manage tags, this is tag allocation policy */
int tag_alloc_policy;
/*
* Track QUEUE_FULL events and reduce queue depth on demand.
*/
unsigned track_queue_depth:1;
/*
* This specifies the mode that a LLD supports.
*/
unsigned supported_mode:2;
/*
* True if this host adapter uses unchecked DMA onto an ISA bus.
*/
unsigned unchecked_isa_dma:1;
/*
* True if this host adapter can make good use of clustering.
* I originally thought that if the tablesize was large that it
* was a waste of CPU cycles to prepare a cluster list, but
* it works out that the Buslogic is faster if you use a smaller
* number of segments (i.e. use clustering). I guess it is
* inefficient.
*/
unsigned use_clustering:1;
/*
* True for emulated SCSI host adapters (e.g. ATAPI).
*/
unsigned emulated:1;
/*
* True if the low-level driver performs its own reset-settle delays.
*/
unsigned skip_settle_delay:1;
/* True if the controller does not support WRITE SAME */
unsigned no_write_same:1;
/* True if the low-level driver supports blk-mq only */
unsigned force_blk_mq:1;
/*
* Countdown for host blocking with no commands outstanding.
*/
unsigned int max_host_blocked;
/*
* Default value for the blocking. If the queue is empty,
* host_blocked counts down in the request_fn until it restarts
* host operations as zero is reached.
*
* FIXME: This should probably be a value in the template
*/
#define SCSI_DEFAULT_HOST_BLOCKED 7
/*
* Pointer to the sysfs class properties for this host, NULL terminated.
*/
struct device_attribute **shost_attrs;
/*
* Pointer to the SCSI device properties for this host, NULL terminated.
*/
struct device_attribute **sdev_attrs;
/*
* Pointer to the SCSI device attribute groups for this host,
* NULL terminated.
*/
const struct attribute_group **sdev_groups;
/*
* Vendor Identifier associated with the host
*
* Note: When specifying vendor_id, be sure to read the
* Vendor Type and ID formatting requirements specified in
* scsi_netlink.h
*/
u64 vendor_id;
/*
* Additional per-command data allocated for the driver.
*/
unsigned int cmd_size;
struct scsi_host_cmd_pool *cmd_pool;
};
/*
* Temporary #define for host lock push down. Can be removed when all
* drivers have been updated to take advantage of unlocked
* queuecommand.
*
*/
#define DEF_SCSI_QCMD(func_name) \
int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
{ \
unsigned long irq_flags; \
int rc; \
spin_lock_irqsave(shost->host_lock, irq_flags); \
scsi_cmd_get_serial(shost, cmd); \
rc = func_name##_lck (cmd, cmd->scsi_done); \
spin_unlock_irqrestore(shost->host_lock, irq_flags); \
return rc; \
}
/*
* shost state: If you alter this, you also need to alter scsi_sysfs.c
* (for the ascii descriptions) and the state model enforcer:
* scsi_host_set_state()
*/
enum scsi_host_state {
SHOST_CREATED = 1,
SHOST_RUNNING,
SHOST_CANCEL,
SHOST_DEL,
SHOST_RECOVERY,
SHOST_CANCEL_RECOVERY,
SHOST_DEL_RECOVERY,
};
struct Scsi_Host {
/*
* __devices is protected by the host_lock, but you should
* usually use scsi_device_lookup / shost_for_each_device
* to access it and don't care about locking yourself.
* In the rare case of being in irq context you can use
* their __ prefixed variants with the lock held. NEVER
* access this list directly from a driver.
*/
struct list_head __devices;
struct list_head __targets;
struct list_head starved_list;
spinlock_t default_lock;
spinlock_t *host_lock;
struct mutex scan_mutex;/* serialize scanning activity */
struct list_head eh_cmd_q;
struct task_struct * ehandler; /* Error recovery thread. */
struct completion * eh_action; /* Wait for specific actions on the
host. */
wait_queue_head_t host_wait;
struct scsi_host_template *hostt;
struct scsi_transport_template *transportt;
/*
* Area to keep a shared tag map (if needed, will be
* NULL if not).
*/
union {
struct blk_queue_tag *bqt;
struct blk_mq_tag_set tag_set;
};
atomic_t host_busy; /* commands actually active on low-level */
atomic_t host_blocked;
unsigned int host_failed; /* commands that failed.
protected by host_lock */
unsigned int host_eh_scheduled; /* EH scheduled without command */
unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
/* next two fields are used to bound the time spent in error handling */
int eh_deadline;
unsigned long last_reset;
/*
* These three parameters can be used to allow for wide scsi,
* and for host adapters that support multiple busses
* The last two should be set to 1 more than the actual max id
* or lun (e.g. 8 for SCSI parallel systems).
*/
unsigned int max_channel;
unsigned int max_id;
u64 max_lun;
/*
* This is a unique identifier that must be assigned so that we
* have some way of identifying each detected host adapter properly
* and uniquely. For hosts that do not support more than one card
* in the system at one time, this does not need to be set. It is
* initialized to 0 in scsi_register.
*/
unsigned int unique_id;
/*
* The maximum length of SCSI commands that this host can accept.
* Probably 12 for most host adapters, but could be 16 for others.
* or 260 if the driver supports variable length cdbs.
* For drivers that don't set this field, a value of 12 is
* assumed.
*/
unsigned short max_cmd_len;
int this_id;
int can_queue;
short cmd_per_lun;
short unsigned int sg_tablesize;
short unsigned int sg_prot_tablesize;
unsigned int max_sectors;
unsigned long dma_boundary;
/*
* In scsi-mq mode, the number of hardware queues supported by the LLD.
*
* Note: it is assumed that each hardware queue has a queue depth of
* can_queue. In other words, the total queue depth per host
* is nr_hw_queues * can_queue.
*/
unsigned nr_hw_queues;
/*
* Used to assign serial numbers to the cmds.
* Protected by the host lock.
*/
unsigned long cmd_serial_number;
unsigned active_mode:2;
unsigned unchecked_isa_dma:1;
unsigned use_clustering:1;
/*
* Host has requested that no further requests come through for the
* time being.
*/
unsigned host_self_blocked:1;
/*
* Host uses correct SCSI ordering not PC ordering. The bit is
* set for the minority of drivers whose authors actually read
* the spec ;).
*/
unsigned reverse_ordering:1;
/* Task mgmt function in progress */
unsigned tmf_in_progress:1;
/* Asynchronous scan in progress */
unsigned async_scan:1;
/* Don't resume host in EH */
unsigned eh_noresume:1;
/* The controller does not support WRITE SAME */
unsigned no_write_same:1;
unsigned use_blk_mq:1;
unsigned use_cmd_list:1;
/* Host responded with short (<36 bytes) INQUIRY result */
unsigned short_inquiry:1;
/*
* Optional work queue to be utilized by the transport
*/
char work_q_name[20];
struct workqueue_struct *work_q;
/*
* Task management function work queue
*/
struct workqueue_struct *tmf_work_q;
/* The transport requires the LUN bits NOT to be stored in CDB[1] */
unsigned no_scsi2_lun_in_cdb:1;
/*
* Value host_blocked counts down from
*/
unsigned int max_host_blocked;
/* Protection Information */
unsigned int prot_capabilities;
unsigned char prot_guard_type;
/* legacy crap */
unsigned long base;
unsigned long io_port;
unsigned char n_io_port;
unsigned char dma_channel;
unsigned int irq;
enum scsi_host_state shost_state;
/* ldm bits */
struct device shost_gendev, shost_dev;
/*
* Points to the transport data (if any) which is allocated
* separately
*/
void *shost_data;
/*
* Points to the physical bus device we'd use to do DMA
* Needed just in case we have virtual hosts.
*/
struct device *dma_dev;
/*
* We should ensure that this is aligned, both for better performance
* and also because some compilers (m68k) don't automatically force
* alignment to a long boundary.
*/
unsigned long hostdata[0] /* Used for storage of host specific stuff */
__attribute__ ((aligned (sizeof(unsigned long))));
};
#define class_to_shost(d) \
container_of(d, struct Scsi_Host, shost_dev)
#define shost_printk(prefix, shost, fmt, a...) \
dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
static inline void *shost_priv(struct Scsi_Host *shost)
{
return (void *)shost->hostdata;
}
int scsi_is_host_device(const struct device *);
static inline struct Scsi_Host *dev_to_shost(struct device *dev)
{
while (!scsi_is_host_device(dev)) {
if (!dev->parent)
return NULL;
dev = dev->parent;
}
return container_of(dev, struct Scsi_Host, shost_gendev);
}
static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
{
return shost->shost_state == SHOST_RECOVERY ||
shost->shost_state == SHOST_CANCEL_RECOVERY ||
shost->shost_state == SHOST_DEL_RECOVERY ||
shost->tmf_in_progress;
}
static inline bool shost_use_blk_mq(struct Scsi_Host *shost)
{
return shost->use_blk_mq;
}
extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
extern void scsi_flush_work(struct Scsi_Host *);
extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
struct device *,
struct device *);
extern void scsi_scan_host(struct Scsi_Host *);
extern void scsi_rescan_device(struct device *);
extern void scsi_remove_host(struct Scsi_Host *);
extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
extern int scsi_host_busy(struct Scsi_Host *shost);
extern void scsi_host_put(struct Scsi_Host *t);
extern struct Scsi_Host *scsi_host_lookup(unsigned short);
extern const char *scsi_host_state_name(enum scsi_host_state);
extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *);
static inline int __must_check scsi_add_host(struct Scsi_Host *host,
struct device *dev)
{
return scsi_add_host_with_dma(host, dev, dev);
}
static inline struct device *scsi_get_device(struct Scsi_Host *shost)
{
return shost->shost_gendev.parent;
}
/**
* scsi_host_scan_allowed - Is scanning of this host allowed
* @shost: Pointer to Scsi_Host.
**/
static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
{
return shost->shost_state == SHOST_RUNNING ||
shost->shost_state == SHOST_RECOVERY;
}
extern void scsi_unblock_requests(struct Scsi_Host *);
extern void scsi_block_requests(struct Scsi_Host *);
struct class_container;
/*
* These two functions are used to allocate and free a pseudo device
* which will connect to the host adapter itself rather than any
* physical device. You must deallocate when you are done with the
* thing. This physical pseudo-device isn't real and won't be available
* from any high-level drivers.
*/
extern void scsi_free_host_dev(struct scsi_device *);
extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
/*
* DIF defines the exchange of protection information between
* initiator and SBC block device.
*
* DIX defines the exchange of protection information between OS and
* initiator.
*/
enum scsi_host_prot_capabilities {
SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
};
/*
* SCSI hosts which support the Data Integrity Extensions must
* indicate their capabilities by setting the prot_capabilities using
* this call.
*/
static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
{
shost->prot_capabilities = mask;
}
static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
{
return shost->prot_capabilities;
}
static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
{
return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
}
static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
{
static unsigned char cap[] = { 0,
SHOST_DIF_TYPE1_PROTECTION,
SHOST_DIF_TYPE2_PROTECTION,
SHOST_DIF_TYPE3_PROTECTION };
if (target_type >= ARRAY_SIZE(cap))
return 0;
return shost->prot_capabilities & cap[target_type] ? target_type : 0;
}
static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
{
#if defined(CONFIG_BLK_DEV_INTEGRITY)
static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
SHOST_DIX_TYPE1_PROTECTION,
SHOST_DIX_TYPE2_PROTECTION,
SHOST_DIX_TYPE3_PROTECTION };
if (target_type >= ARRAY_SIZE(cap))
return 0;
return shost->prot_capabilities & cap[target_type];
#endif
return 0;
}
/*
* All DIX-capable initiators must support the T10-mandated CRC
* checksum. Controllers can optionally implement the IP checksum
* scheme which has much lower impact on system performance. Note
* that the main rationale for the checksum is to match integrity
* metadata with data. Detecting bit errors are a job for ECC memory
* and buses.
*/
enum scsi_host_guard_type {
SHOST_DIX_GUARD_CRC = 1 << 0,
SHOST_DIX_GUARD_IP = 1 << 1,
};
static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
{
shost->prot_guard_type = type;
}
static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
{
return shost->prot_guard_type;
}
extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
#endif /* _SCSI_SCSI_HOST_H */
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