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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _SCSI_SCSI_HOST_H3#define _SCSI_SCSI_HOST_H4 5#include <linux/device.h>6#include <linux/list.h>7#include <linux/types.h>8#include <linux/workqueue.h>9#include <linux/mutex.h>10#include <linux/seq_file.h>11#include <linux/blk-mq.h>12#include <scsi/scsi.h>13 14struct block_device;15struct completion;16struct module;17struct scsi_cmnd;18struct scsi_device;19struct scsi_target;20struct Scsi_Host;21struct scsi_transport_template;22 23 24#define SG_ALL SG_CHUNK_SIZE25 26#define MODE_UNKNOWN 0x0027#define MODE_INITIATOR 0x0128#define MODE_TARGET 0x0229 30/**31 * enum scsi_timeout_action - How to handle a command that timed out.32 * @SCSI_EH_DONE: The command has already been completed.33 * @SCSI_EH_RESET_TIMER: Reset the timer and continue waiting for completion.34 * @SCSI_EH_NOT_HANDLED: The command has not yet finished. Abort the command.35 */36enum scsi_timeout_action {37 SCSI_EH_DONE,38 SCSI_EH_RESET_TIMER,39 SCSI_EH_NOT_HANDLED,40};41 42struct scsi_host_template {43 /*44 * Put fields referenced in IO submission path together in45 * same cacheline46 */47 48 /*49 * Additional per-command data allocated for the driver.50 */51 unsigned int cmd_size;52 53 /*54 * The queuecommand function is used to queue up a scsi55 * command block to the LLDD. When the driver finished56 * processing the command the done callback is invoked.57 *58 * If queuecommand returns 0, then the driver has accepted the59 * command. It must also push it to the HBA if the scsi_cmnd60 * flag SCMD_LAST is set, or if the driver does not implement61 * commit_rqs. The done() function must be called on the command62 * when the driver has finished with it. (you may call done on the63 * command before queuecommand returns, but in this case you64 * *must* return 0 from queuecommand).65 *66 * Queuecommand may also reject the command, in which case it may67 * not touch the command and must not call done() for it.68 *69 * There are two possible rejection returns:70 *71 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but72 * allow commands to other devices serviced by this host.73 *74 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this75 * host temporarily.76 *77 * For compatibility, any other non-zero return is treated the78 * same as SCSI_MLQUEUE_HOST_BUSY.79 *80 * NOTE: "temporarily" means either until the next command for#81 * this device/host completes, or a period of time determined by82 * I/O pressure in the system if there are no other outstanding83 * commands.84 *85 * STATUS: REQUIRED86 */87 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);88 89 /*90 * The commit_rqs function is used to trigger a hardware91 * doorbell after some requests have been queued with92 * queuecommand, when an error is encountered before sending93 * the request with SCMD_LAST set.94 *95 * STATUS: OPTIONAL96 */97 void (*commit_rqs)(struct Scsi_Host *, u16);98 99 struct module *module;100 const char *name;101 102 /*103 * The info function will return whatever useful information the104 * developer sees fit. If not provided, then the name field will105 * be used instead.106 *107 * Status: OPTIONAL108 */109 const char *(*info)(struct Scsi_Host *);110 111 /*112 * Ioctl interface113 *114 * Status: OPTIONAL115 */116 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,117 void __user *arg);118 119 120#ifdef CONFIG_COMPAT121 /*122 * Compat handler. Handle 32bit ABI.123 * When unknown ioctl is passed return -ENOIOCTLCMD.124 *125 * Status: OPTIONAL126 */127 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,128 void __user *arg);129#endif130 131 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);132 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);133 134 /*135 * This is an error handling strategy routine. You don't need to136 * define one of these if you don't want to - there is a default137 * routine that is present that should work in most cases. For those138 * driver authors that have the inclination and ability to write their139 * own strategy routine, this is where it is specified. Note - the140 * strategy routine is *ALWAYS* run in the context of the kernel eh141 * thread. Thus you are guaranteed to *NOT* be in an interrupt142 * handler when you execute this, and you are also guaranteed to143 * *NOT* have any other commands being queued while you are in the144 * strategy routine. When you return from this function, operations145 * return to normal.146 *147 * See scsi_error.c scsi_unjam_host for additional comments about148 * what this function should and should not be attempting to do.149 *150 * Status: REQUIRED (at least one of them)151 */152 int (* eh_abort_handler)(struct scsi_cmnd *);153 int (* eh_device_reset_handler)(struct scsi_cmnd *);154 int (* eh_target_reset_handler)(struct scsi_cmnd *);155 int (* eh_bus_reset_handler)(struct scsi_cmnd *);156 int (* eh_host_reset_handler)(struct scsi_cmnd *);157 158 /*159 * Before the mid layer attempts to scan for a new device where none160 * currently exists, it will call this entry in your driver. Should161 * your driver need to allocate any structs or perform any other init162 * items in order to send commands to a currently unused target/lun163 * combo, then this is where you can perform those allocations. This164 * is specifically so that drivers won't have to perform any kind of165 * "is this a new device" checks in their queuecommand routine,166 * thereby making the hot path a bit quicker.167 *168 * Return values: 0 on success, non-0 on failure169 *170 * Deallocation: If we didn't find any devices at this ID, you will171 * get an immediate call to slave_destroy(). If we find something172 * here then you will get a call to slave_configure(), then the173 * device will be used for however long it is kept around, then when174 * the device is removed from the system (or * possibly at reboot175 * time), you will then get a call to slave_destroy(). This is176 * assuming you implement slave_configure and slave_destroy.177 * However, if you allocate memory and hang it off the device struct,178 * then you must implement the slave_destroy() routine at a minimum179 * in order to avoid leaking memory180 * each time a device is tore down.181 *182 * Status: OPTIONAL183 */184 int (* slave_alloc)(struct scsi_device *);185 186 /*187 * Once the device has responded to an INQUIRY and we know the188 * device is online, we call into the low level driver with the189 * struct scsi_device *. If the low level device driver implements190 * this function, it *must* perform the task of setting the queue191 * depth on the device. All other tasks are optional and depend192 * on what the driver supports and various implementation details.193 * 194 * Things currently recommended to be handled at this time include:195 *196 * 1. Setting the device queue depth. Proper setting of this is197 * described in the comments for scsi_change_queue_depth.198 * 2. Determining if the device supports the various synchronous199 * negotiation protocols. The device struct will already have200 * responded to INQUIRY and the results of the standard items201 * will have been shoved into the various device flag bits, eg.202 * device->sdtr will be true if the device supports SDTR messages.203 * 3. Allocating command structs that the device will need.204 * 4. Setting the default timeout on this device (if needed).205 * 5. Anything else the low level driver might want to do on a device206 * specific setup basis...207 * 6. Return 0 on success, non-0 on error. The device will be marked208 * as offline on error so that no access will occur. If you return209 * non-0, your slave_destroy routine will never get called for this210 * device, so don't leave any loose memory hanging around, clean211 * up after yourself before returning non-0212 *213 * Status: OPTIONAL214 *215 * Note: slave_configure is the legacy version, use device_configure for216 * all new code. A driver must never define both.217 */218 int (* device_configure)(struct scsi_device *, struct queue_limits *lim);219 int (* slave_configure)(struct scsi_device *);220 221 /*222 * Immediately prior to deallocating the device and after all activity223 * has ceased the mid layer calls this point so that the low level224 * driver may completely detach itself from the scsi device and vice225 * versa. The low level driver is responsible for freeing any memory226 * it allocated in the slave_alloc or slave_configure calls. 227 *228 * Status: OPTIONAL229 */230 void (* slave_destroy)(struct scsi_device *);231 232 /*233 * Before the mid layer attempts to scan for a new device attached234 * to a target where no target currently exists, it will call this235 * entry in your driver. Should your driver need to allocate any236 * structs or perform any other init items in order to send commands237 * to a currently unused target, then this is where you can perform238 * those allocations.239 *240 * Return values: 0 on success, non-0 on failure241 *242 * Status: OPTIONAL243 */244 int (* target_alloc)(struct scsi_target *);245 246 /*247 * Immediately prior to deallocating the target structure, and248 * after all activity to attached scsi devices has ceased, the249 * midlayer calls this point so that the driver may deallocate250 * and terminate any references to the target.251 *252 * Note: This callback is called with the host lock held and hence253 * must not sleep.254 *255 * Status: OPTIONAL256 */257 void (* target_destroy)(struct scsi_target *);258 259 /*260 * If a host has the ability to discover targets on its own instead261 * of scanning the entire bus, it can fill in this function and262 * call scsi_scan_host(). This function will be called periodically263 * until it returns 1 with the scsi_host and the elapsed time of264 * the scan in jiffies.265 *266 * Status: OPTIONAL267 */268 int (* scan_finished)(struct Scsi_Host *, unsigned long);269 270 /*271 * If the host wants to be called before the scan starts, but272 * after the midlayer has set up ready for the scan, it can fill273 * in this function.274 *275 * Status: OPTIONAL276 */277 void (* scan_start)(struct Scsi_Host *);278 279 /*280 * Fill in this function to allow the queue depth of this host281 * to be changeable (on a per device basis). Returns either282 * the current queue depth setting (may be different from what283 * was passed in) or an error. An error should only be284 * returned if the requested depth is legal but the driver was285 * unable to set it. If the requested depth is illegal, the286 * driver should set and return the closest legal queue depth.287 *288 * Status: OPTIONAL289 */290 int (* change_queue_depth)(struct scsi_device *, int);291 292 /*293 * This functions lets the driver expose the queue mapping294 * to the block layer.295 *296 * Status: OPTIONAL297 */298 void (* map_queues)(struct Scsi_Host *shost);299 300 /*301 * SCSI interface of blk_poll - poll for IO completions.302 * Only applicable if SCSI LLD exposes multiple h/w queues.303 *304 * Return value: Number of completed entries found.305 *306 * Status: OPTIONAL307 */308 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);309 310 /*311 * Check if scatterlists need to be padded for DMA draining.312 *313 * Status: OPTIONAL314 */315 bool (* dma_need_drain)(struct request *rq);316 317 /*318 * This function determines the BIOS parameters for a given319 * harddisk. These tend to be numbers that are made up by320 * the host adapter. Parameters:321 * size, device, list (heads, sectors, cylinders)322 *323 * Status: OPTIONAL324 */325 int (* bios_param)(struct scsi_device *, struct block_device *,326 sector_t, int []);327 328 /*329 * This function is called when one or more partitions on the330 * device reach beyond the end of the device.331 *332 * Status: OPTIONAL333 */334 void (*unlock_native_capacity)(struct scsi_device *);335 336 /*337 * Can be used to export driver statistics and other infos to the338 * world outside the kernel ie. userspace and it also provides an339 * interface to feed the driver with information.340 *341 * Status: OBSOLETE342 */343 int (*show_info)(struct seq_file *, struct Scsi_Host *);344 int (*write_info)(struct Scsi_Host *, char *, int);345 346 /*347 * This is an optional routine that allows the transport to become348 * involved when a scsi io timer fires. The return value tells the349 * timer routine how to finish the io timeout handling.350 *351 * Status: OPTIONAL352 */353 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);354 /*355 * Optional routine that allows the transport to decide if a cmd356 * is retryable. Return true if the transport is in a state the357 * cmd should be retried on.358 */359 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);360 361 /* This is an optional routine that allows transport to initiate362 * LLD adapter or firmware reset using sysfs attribute.363 *364 * Return values: 0 on success, -ve value on failure.365 *366 * Status: OPTIONAL367 */368 369 int (*host_reset)(struct Scsi_Host *shost, int reset_type);370#define SCSI_ADAPTER_RESET 1371#define SCSI_FIRMWARE_RESET 2372 373 374 /*375 * Name of proc directory376 */377 const char *proc_name;378 379 /*380 * This determines if we will use a non-interrupt driven381 * or an interrupt driven scheme. It is set to the maximum number382 * of simultaneous commands a single hw queue in HBA will accept.383 */384 int can_queue;385 386 /*387 * In many instances, especially where disconnect / reconnect are388 * supported, our host also has an ID on the SCSI bus. If this is389 * the case, then it must be reserved. Please set this_id to -1 if390 * your setup is in single initiator mode, and the host lacks an391 * ID.392 */393 int this_id;394 395 /*396 * This determines the degree to which the host adapter is capable397 * of scatter-gather.398 */399 unsigned short sg_tablesize;400 unsigned short sg_prot_tablesize;401 402 /*403 * Set this if the host adapter has limitations beside segment count.404 */405 unsigned int max_sectors;406 407 /*408 * Maximum size in bytes of a single segment.409 */410 unsigned int max_segment_size;411 412 unsigned int dma_alignment;413 414 /*415 * DMA scatter gather segment boundary limit. A segment crossing this416 * boundary will be split in two.417 */418 unsigned long dma_boundary;419 420 unsigned long virt_boundary_mask;421 422 /*423 * This specifies "machine infinity" for host templates which don't424 * limit the transfer size. Note this limit represents an absolute425 * maximum, and may be over the transfer limits allowed for426 * individual devices (e.g. 256 for SCSI-1).427 */428#define SCSI_DEFAULT_MAX_SECTORS 1024429 430 /*431 * True if this host adapter can make good use of linked commands.432 * This will allow more than one command to be queued to a given433 * unit on a given host. Set this to the maximum number of command434 * blocks to be provided for each device. Set this to 1 for one435 * command block per lun, 2 for two, etc. Do not set this to 0.436 * You should make sure that the host adapter will do the right thing437 * before you try setting this above 1.438 */439 short cmd_per_lun;440 441 /* If use block layer to manage tags, this is tag allocation policy */442 int tag_alloc_policy;443 444 /*445 * Track QUEUE_FULL events and reduce queue depth on demand.446 */447 unsigned track_queue_depth:1;448 449 /*450 * This specifies the mode that a LLD supports.451 */452 unsigned supported_mode:2;453 454 /*455 * True for emulated SCSI host adapters (e.g. ATAPI).456 */457 unsigned emulated:1;458 459 /*460 * True if the low-level driver performs its own reset-settle delays.461 */462 unsigned skip_settle_delay:1;463 464 /* True if the controller does not support WRITE SAME */465 unsigned no_write_same:1;466 467 /* True if the host uses host-wide tagspace */468 unsigned host_tagset:1;469 470 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */471 unsigned queuecommand_may_block:1;472 473 /*474 * Countdown for host blocking with no commands outstanding.475 */476 unsigned int max_host_blocked;477 478 /*479 * Default value for the blocking. If the queue is empty,480 * host_blocked counts down in the request_fn until it restarts481 * host operations as zero is reached. 482 *483 * FIXME: This should probably be a value in the template484 */485#define SCSI_DEFAULT_HOST_BLOCKED 7486 487 /*488 * Pointer to the SCSI host sysfs attribute groups, NULL terminated.489 */490 const struct attribute_group **shost_groups;491 492 /*493 * Pointer to the SCSI device attribute groups for this host,494 * NULL terminated.495 */496 const struct attribute_group **sdev_groups;497 498 /*499 * Vendor Identifier associated with the host500 *501 * Note: When specifying vendor_id, be sure to read the502 * Vendor Type and ID formatting requirements specified in503 * scsi_netlink.h504 */505 u64 vendor_id;506};507 508/*509 * Temporary #define for host lock push down. Can be removed when all510 * drivers have been updated to take advantage of unlocked511 * queuecommand.512 *513 */514#define DEF_SCSI_QCMD(func_name) \515 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \516 { \517 unsigned long irq_flags; \518 int rc; \519 spin_lock_irqsave(shost->host_lock, irq_flags); \520 rc = func_name##_lck(cmd); \521 spin_unlock_irqrestore(shost->host_lock, irq_flags); \522 return rc; \523 }524 525 526/*527 * shost state: If you alter this, you also need to alter scsi_sysfs.c528 * (for the ascii descriptions) and the state model enforcer:529 * scsi_host_set_state()530 */531enum scsi_host_state {532 SHOST_CREATED = 1,533 SHOST_RUNNING,534 SHOST_CANCEL,535 SHOST_DEL,536 SHOST_RECOVERY,537 SHOST_CANCEL_RECOVERY,538 SHOST_DEL_RECOVERY,539};540 541struct Scsi_Host {542 /*543 * __devices is protected by the host_lock, but you should544 * usually use scsi_device_lookup / shost_for_each_device545 * to access it and don't care about locking yourself.546 * In the rare case of being in irq context you can use547 * their __ prefixed variants with the lock held. NEVER548 * access this list directly from a driver.549 */550 struct list_head __devices;551 struct list_head __targets;552 553 struct list_head starved_list;554 555 spinlock_t default_lock;556 spinlock_t *host_lock;557 558 struct mutex scan_mutex;/* serialize scanning activity */559 560 struct list_head eh_abort_list;561 struct list_head eh_cmd_q;562 struct task_struct * ehandler; /* Error recovery thread. */563 struct completion * eh_action; /* Wait for specific actions on the564 host. */565 wait_queue_head_t host_wait;566 const struct scsi_host_template *hostt;567 struct scsi_transport_template *transportt;568 569 struct kref tagset_refcnt;570 struct completion tagset_freed;571 /* Area to keep a shared tag map */572 struct blk_mq_tag_set tag_set;573 574 atomic_t host_blocked;575 576 unsigned int host_failed; /* commands that failed.577 protected by host_lock */578 unsigned int host_eh_scheduled; /* EH scheduled without command */579 580 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */581 582 /* next two fields are used to bound the time spent in error handling */583 int eh_deadline;584 unsigned long last_reset;585 586 587 /*588 * These three parameters can be used to allow for wide scsi,589 * and for host adapters that support multiple busses590 * The last two should be set to 1 more than the actual max id591 * or lun (e.g. 8 for SCSI parallel systems).592 */593 unsigned int max_channel;594 unsigned int max_id;595 u64 max_lun;596 597 /*598 * This is a unique identifier that must be assigned so that we599 * have some way of identifying each detected host adapter properly600 * and uniquely. For hosts that do not support more than one card601 * in the system at one time, this does not need to be set. It is602 * initialized to 0 in scsi_register.603 */604 unsigned int unique_id;605 606 /*607 * The maximum length of SCSI commands that this host can accept.608 * Probably 12 for most host adapters, but could be 16 for others.609 * or 260 if the driver supports variable length cdbs.610 * For drivers that don't set this field, a value of 12 is611 * assumed.612 */613 unsigned short max_cmd_len;614 615 int this_id;616 int can_queue;617 short cmd_per_lun;618 short unsigned int sg_tablesize;619 short unsigned int sg_prot_tablesize;620 unsigned int max_sectors;621 unsigned int opt_sectors;622 unsigned int max_segment_size;623 unsigned int dma_alignment;624 unsigned long dma_boundary;625 unsigned long virt_boundary_mask;626 /*627 * In scsi-mq mode, the number of hardware queues supported by the LLD.628 *629 * Note: it is assumed that each hardware queue has a queue depth of630 * can_queue. In other words, the total queue depth per host631 * is nr_hw_queues * can_queue. However, for when host_tagset is set,632 * the total queue depth is can_queue.633 */634 unsigned nr_hw_queues;635 unsigned nr_maps;636 unsigned active_mode:2;637 638 /*639 * Host has requested that no further requests come through for the640 * time being.641 */642 unsigned host_self_blocked:1;643 644 /*645 * Host uses correct SCSI ordering not PC ordering. The bit is646 * set for the minority of drivers whose authors actually read647 * the spec ;).648 */649 unsigned reverse_ordering:1;650 651 /* Task mgmt function in progress */652 unsigned tmf_in_progress:1;653 654 /* Asynchronous scan in progress */655 unsigned async_scan:1;656 657 /* Don't resume host in EH */658 unsigned eh_noresume:1;659 660 /* The controller does not support WRITE SAME */661 unsigned no_write_same:1;662 663 /* True if the host uses host-wide tagspace */664 unsigned host_tagset:1;665 666 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */667 unsigned queuecommand_may_block:1;668 669 /* Host responded with short (<36 bytes) INQUIRY result */670 unsigned short_inquiry:1;671 672 /* The transport requires the LUN bits NOT to be stored in CDB[1] */673 unsigned no_scsi2_lun_in_cdb:1;674 675 unsigned no_highmem:1;676 677 /*678 * Optional work queue to be utilized by the transport679 */680 struct workqueue_struct *work_q;681 682 /*683 * Task management function work queue684 */685 struct workqueue_struct *tmf_work_q;686 687 /*688 * Value host_blocked counts down from689 */690 unsigned int max_host_blocked;691 692 /* Protection Information */693 unsigned int prot_capabilities;694 unsigned char prot_guard_type;695 696 /* legacy crap */697 unsigned long base;698 unsigned long io_port;699 unsigned char n_io_port;700 unsigned char dma_channel;701 unsigned int irq;702 703 704 enum scsi_host_state shost_state;705 706 /* ldm bits */707 struct device shost_gendev, shost_dev;708 709 /*710 * Points to the transport data (if any) which is allocated711 * separately712 */713 void *shost_data;714 715 /*716 * Points to the physical bus device we'd use to do DMA717 * Needed just in case we have virtual hosts.718 */719 struct device *dma_dev;720 721 /* Delay for runtime autosuspend */722 int rpm_autosuspend_delay;723 724 /*725 * We should ensure that this is aligned, both for better performance726 * and also because some compilers (m68k) don't automatically force727 * alignment to a long boundary.728 */729 unsigned long hostdata[] /* Used for storage of host specific stuff */730 __attribute__ ((aligned (sizeof(unsigned long))));731};732 733#define class_to_shost(d) \734 container_of(d, struct Scsi_Host, shost_dev)735 736#define shost_printk(prefix, shost, fmt, a...) \737 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)738 739static inline void *shost_priv(struct Scsi_Host *shost)740{741 return (void *)shost->hostdata;742}743 744int scsi_is_host_device(const struct device *);745 746static inline struct Scsi_Host *dev_to_shost(struct device *dev)747{748 while (!scsi_is_host_device(dev)) {749 if (!dev->parent)750 return NULL;751 dev = dev->parent;752 }753 return container_of(dev, struct Scsi_Host, shost_gendev);754}755 756static inline int scsi_host_in_recovery(struct Scsi_Host *shost)757{758 return shost->shost_state == SHOST_RECOVERY ||759 shost->shost_state == SHOST_CANCEL_RECOVERY ||760 shost->shost_state == SHOST_DEL_RECOVERY ||761 shost->tmf_in_progress;762}763 764extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);765extern void scsi_flush_work(struct Scsi_Host *);766 767extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int);768extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,769 struct device *,770 struct device *);771#if defined(CONFIG_SCSI_PROC_FS)772struct proc_dir_entry *773scsi_template_proc_dir(const struct scsi_host_template *sht);774#else775#define scsi_template_proc_dir(sht) NULL776#endif777extern void scsi_scan_host(struct Scsi_Host *);778extern int scsi_resume_device(struct scsi_device *sdev);779extern int scsi_rescan_device(struct scsi_device *sdev);780extern void scsi_remove_host(struct Scsi_Host *);781extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);782extern int scsi_host_busy(struct Scsi_Host *shost);783extern void scsi_host_put(struct Scsi_Host *t);784extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);785extern const char *scsi_host_state_name(enum scsi_host_state);786extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,787 enum scsi_host_status status);788 789static inline int __must_check scsi_add_host(struct Scsi_Host *host,790 struct device *dev)791{792 return scsi_add_host_with_dma(host, dev, dev);793}794 795static inline struct device *scsi_get_device(struct Scsi_Host *shost)796{797 return shost->shost_gendev.parent;798}799 800/**801 * scsi_host_scan_allowed - Is scanning of this host allowed802 * @shost: Pointer to Scsi_Host.803 **/804static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)805{806 return shost->shost_state == SHOST_RUNNING ||807 shost->shost_state == SHOST_RECOVERY;808}809 810extern void scsi_unblock_requests(struct Scsi_Host *);811extern void scsi_block_requests(struct Scsi_Host *);812extern int scsi_host_block(struct Scsi_Host *shost);813extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);814 815void scsi_host_busy_iter(struct Scsi_Host *,816 bool (*fn)(struct scsi_cmnd *, void *), void *priv);817 818struct class_container;819 820/*821 * DIF defines the exchange of protection information between822 * initiator and SBC block device.823 *824 * DIX defines the exchange of protection information between OS and825 * initiator.826 */827enum scsi_host_prot_capabilities {828 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */829 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */830 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */831 832 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */833 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */834 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */835 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */836};837 838/*839 * SCSI hosts which support the Data Integrity Extensions must840 * indicate their capabilities by setting the prot_capabilities using841 * this call.842 */843static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)844{845 shost->prot_capabilities = mask;846}847 848static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)849{850 return shost->prot_capabilities;851}852 853static inline int scsi_host_prot_dma(struct Scsi_Host *shost)854{855 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;856}857 858static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)859{860 static unsigned char cap[] = { 0,861 SHOST_DIF_TYPE1_PROTECTION,862 SHOST_DIF_TYPE2_PROTECTION,863 SHOST_DIF_TYPE3_PROTECTION };864 865 if (target_type >= ARRAY_SIZE(cap))866 return 0;867 868 return shost->prot_capabilities & cap[target_type] ? target_type : 0;869}870 871static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)872{873#if defined(CONFIG_BLK_DEV_INTEGRITY)874 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,875 SHOST_DIX_TYPE1_PROTECTION,876 SHOST_DIX_TYPE2_PROTECTION,877 SHOST_DIX_TYPE3_PROTECTION };878 879 if (target_type >= ARRAY_SIZE(cap))880 return 0;881 882 return shost->prot_capabilities & cap[target_type];883#endif884 return 0;885}886 887/*888 * All DIX-capable initiators must support the T10-mandated CRC889 * checksum. Controllers can optionally implement the IP checksum890 * scheme which has much lower impact on system performance. Note891 * that the main rationale for the checksum is to match integrity892 * metadata with data. Detecting bit errors are a job for ECC memory893 * and buses.894 */895 896enum scsi_host_guard_type {897 SHOST_DIX_GUARD_CRC = 1 << 0,898 SHOST_DIX_GUARD_IP = 1 << 1,899};900 901static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)902{903 shost->prot_guard_type = type;904}905 906static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)907{908 return shost->prot_guard_type;909}910 911extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);912 913#endif /* _SCSI_SCSI_HOST_H */914