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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _SCSI_SCSI_HOST_H
3#define _SCSI_SCSI_HOST_H
4
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_host_cmd_pool;
20struct scsi_target;
21struct Scsi_Host;
22struct scsi_host_cmd_pool;
23struct scsi_transport_template;
24
25
26#define SG_ALL SG_CHUNK_SIZE
27
28#define MODE_UNKNOWN 0x00
29#define MODE_INITIATOR 0x01
30#define MODE_TARGET 0x02
31
32struct scsi_host_template {
33 struct module *module;
34 const char *name;
35
36 /*
37 * The info function will return whatever useful information the
38 * developer sees fit. If not provided, then the name field will
39 * be used instead.
40 *
41 * Status: OPTIONAL
42 */
43 const char *(* info)(struct Scsi_Host *);
44
45 /*
46 * Ioctl interface
47 *
48 * Status: OPTIONAL
49 */
50 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
51 void __user *arg);
52
53
54#ifdef CONFIG_COMPAT
55 /*
56 * Compat handler. Handle 32bit ABI.
57 * When unknown ioctl is passed return -ENOIOCTLCMD.
58 *
59 * Status: OPTIONAL
60 */
61 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
62 void __user *arg);
63#endif
64
65 int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
66 int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);
67
68 /*
69 * The queuecommand function is used to queue up a scsi
70 * command block to the LLDD. When the driver finished
71 * processing the command the done callback is invoked.
72 *
73 * If queuecommand returns 0, then the driver has accepted the
74 * command. It must also push it to the HBA if the scsi_cmnd
75 * flag SCMD_LAST is set, or if the driver does not implement
76 * commit_rqs. The done() function must be called on the command
77 * when the driver has finished with it. (you may call done on the
78 * command before queuecommand returns, but in this case you
79 * *must* return 0 from queuecommand).
80 *
81 * Queuecommand may also reject the command, in which case it may
82 * not touch the command and must not call done() for it.
83 *
84 * There are two possible rejection returns:
85 *
86 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
87 * allow commands to other devices serviced by this host.
88 *
89 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
90 * host temporarily.
91 *
92 * For compatibility, any other non-zero return is treated the
93 * same as SCSI_MLQUEUE_HOST_BUSY.
94 *
95 * NOTE: "temporarily" means either until the next command for#
96 * this device/host completes, or a period of time determined by
97 * I/O pressure in the system if there are no other outstanding
98 * commands.
99 *
100 * STATUS: REQUIRED
101 */
102 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
103
104 /*
105 * The commit_rqs function is used to trigger a hardware
106 * doorbell after some requests have been queued with
107 * queuecommand, when an error is encountered before sending
108 * the request with SCMD_LAST set.
109 *
110 * STATUS: OPTIONAL
111 */
112 void (*commit_rqs)(struct Scsi_Host *, u16);
113
114 /*
115 * This is an error handling strategy routine. You don't need to
116 * define one of these if you don't want to - there is a default
117 * routine that is present that should work in most cases. For those
118 * driver authors that have the inclination and ability to write their
119 * own strategy routine, this is where it is specified. Note - the
120 * strategy routine is *ALWAYS* run in the context of the kernel eh
121 * thread. Thus you are guaranteed to *NOT* be in an interrupt
122 * handler when you execute this, and you are also guaranteed to
123 * *NOT* have any other commands being queued while you are in the
124 * strategy routine. When you return from this function, operations
125 * return to normal.
126 *
127 * See scsi_error.c scsi_unjam_host for additional comments about
128 * what this function should and should not be attempting to do.
129 *
130 * Status: REQUIRED (at least one of them)
131 */
132 int (* eh_abort_handler)(struct scsi_cmnd *);
133 int (* eh_device_reset_handler)(struct scsi_cmnd *);
134 int (* eh_target_reset_handler)(struct scsi_cmnd *);
135 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
136 int (* eh_host_reset_handler)(struct scsi_cmnd *);
137
138 /*
139 * Before the mid layer attempts to scan for a new device where none
140 * currently exists, it will call this entry in your driver. Should
141 * your driver need to allocate any structs or perform any other init
142 * items in order to send commands to a currently unused target/lun
143 * combo, then this is where you can perform those allocations. This
144 * is specifically so that drivers won't have to perform any kind of
145 * "is this a new device" checks in their queuecommand routine,
146 * thereby making the hot path a bit quicker.
147 *
148 * Return values: 0 on success, non-0 on failure
149 *
150 * Deallocation: If we didn't find any devices at this ID, you will
151 * get an immediate call to slave_destroy(). If we find something
152 * here then you will get a call to slave_configure(), then the
153 * device will be used for however long it is kept around, then when
154 * the device is removed from the system (or * possibly at reboot
155 * time), you will then get a call to slave_destroy(). This is
156 * assuming you implement slave_configure and slave_destroy.
157 * However, if you allocate memory and hang it off the device struct,
158 * then you must implement the slave_destroy() routine at a minimum
159 * in order to avoid leaking memory
160 * each time a device is tore down.
161 *
162 * Status: OPTIONAL
163 */
164 int (* slave_alloc)(struct scsi_device *);
165
166 /*
167 * Once the device has responded to an INQUIRY and we know the
168 * device is online, we call into the low level driver with the
169 * struct scsi_device *. If the low level device driver implements
170 * this function, it *must* perform the task of setting the queue
171 * depth on the device. All other tasks are optional and depend
172 * on what the driver supports and various implementation details.
173 *
174 * Things currently recommended to be handled at this time include:
175 *
176 * 1. Setting the device queue depth. Proper setting of this is
177 * described in the comments for scsi_change_queue_depth.
178 * 2. Determining if the device supports the various synchronous
179 * negotiation protocols. The device struct will already have
180 * responded to INQUIRY and the results of the standard items
181 * will have been shoved into the various device flag bits, eg.
182 * device->sdtr will be true if the device supports SDTR messages.
183 * 3. Allocating command structs that the device will need.
184 * 4. Setting the default timeout on this device (if needed).
185 * 5. Anything else the low level driver might want to do on a device
186 * specific setup basis...
187 * 6. Return 0 on success, non-0 on error. The device will be marked
188 * as offline on error so that no access will occur. If you return
189 * non-0, your slave_destroy routine will never get called for this
190 * device, so don't leave any loose memory hanging around, clean
191 * up after yourself before returning non-0
192 *
193 * Status: OPTIONAL
194 */
195 int (* slave_configure)(struct scsi_device *);
196
197 /*
198 * Immediately prior to deallocating the device and after all activity
199 * has ceased the mid layer calls this point so that the low level
200 * driver may completely detach itself from the scsi device and vice
201 * versa. The low level driver is responsible for freeing any memory
202 * it allocated in the slave_alloc or slave_configure calls.
203 *
204 * Status: OPTIONAL
205 */
206 void (* slave_destroy)(struct scsi_device *);
207
208 /*
209 * Before the mid layer attempts to scan for a new device attached
210 * to a target where no target currently exists, it will call this
211 * entry in your driver. Should your driver need to allocate any
212 * structs or perform any other init items in order to send commands
213 * to a currently unused target, then this is where you can perform
214 * those allocations.
215 *
216 * Return values: 0 on success, non-0 on failure
217 *
218 * Status: OPTIONAL
219 */
220 int (* target_alloc)(struct scsi_target *);
221
222 /*
223 * Immediately prior to deallocating the target structure, and
224 * after all activity to attached scsi devices has ceased, the
225 * midlayer calls this point so that the driver may deallocate
226 * and terminate any references to the target.
227 *
228 * Status: OPTIONAL
229 */
230 void (* target_destroy)(struct scsi_target *);
231
232 /*
233 * If a host has the ability to discover targets on its own instead
234 * of scanning the entire bus, it can fill in this function and
235 * call scsi_scan_host(). This function will be called periodically
236 * until it returns 1 with the scsi_host and the elapsed time of
237 * the scan in jiffies.
238 *
239 * Status: OPTIONAL
240 */
241 int (* scan_finished)(struct Scsi_Host *, unsigned long);
242
243 /*
244 * If the host wants to be called before the scan starts, but
245 * after the midlayer has set up ready for the scan, it can fill
246 * in this function.
247 *
248 * Status: OPTIONAL
249 */
250 void (* scan_start)(struct Scsi_Host *);
251
252 /*
253 * Fill in this function to allow the queue depth of this host
254 * to be changeable (on a per device basis). Returns either
255 * the current queue depth setting (may be different from what
256 * was passed in) or an error. An error should only be
257 * returned if the requested depth is legal but the driver was
258 * unable to set it. If the requested depth is illegal, the
259 * driver should set and return the closest legal queue depth.
260 *
261 * Status: OPTIONAL
262 */
263 int (* change_queue_depth)(struct scsi_device *, int);
264
265 /*
266 * This functions lets the driver expose the queue mapping
267 * to the block layer.
268 *
269 * Status: OPTIONAL
270 */
271 int (* map_queues)(struct Scsi_Host *shost);
272
273 /*
274 * Check if scatterlists need to be padded for DMA draining.
275 *
276 * Status: OPTIONAL
277 */
278 bool (* dma_need_drain)(struct request *rq);
279
280 /*
281 * This function determines the BIOS parameters for a given
282 * harddisk. These tend to be numbers that are made up by
283 * the host adapter. Parameters:
284 * size, device, list (heads, sectors, cylinders)
285 *
286 * Status: OPTIONAL
287 */
288 int (* bios_param)(struct scsi_device *, struct block_device *,
289 sector_t, int []);
290
291 /*
292 * This function is called when one or more partitions on the
293 * device reach beyond the end of the device.
294 *
295 * Status: OPTIONAL
296 */
297 void (*unlock_native_capacity)(struct scsi_device *);
298
299 /*
300 * Can be used to export driver statistics and other infos to the
301 * world outside the kernel ie. userspace and it also provides an
302 * interface to feed the driver with information.
303 *
304 * Status: OBSOLETE
305 */
306 int (*show_info)(struct seq_file *, struct Scsi_Host *);
307 int (*write_info)(struct Scsi_Host *, char *, int);
308
309 /*
310 * This is an optional routine that allows the transport to become
311 * involved when a scsi io timer fires. The return value tells the
312 * timer routine how to finish the io timeout handling.
313 *
314 * Status: OPTIONAL
315 */
316 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
317
318 /* This is an optional routine that allows transport to initiate
319 * LLD adapter or firmware reset using sysfs attribute.
320 *
321 * Return values: 0 on success, -ve value on failure.
322 *
323 * Status: OPTIONAL
324 */
325
326 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
327#define SCSI_ADAPTER_RESET 1
328#define SCSI_FIRMWARE_RESET 2
329
330
331 /*
332 * Name of proc directory
333 */
334 const char *proc_name;
335
336 /*
337 * Used to store the procfs directory if a driver implements the
338 * show_info method.
339 */
340 struct proc_dir_entry *proc_dir;
341
342 /*
343 * This determines if we will use a non-interrupt driven
344 * or an interrupt driven scheme. It is set to the maximum number
345 * of simultaneous commands a single hw queue in HBA will accept.
346 */
347 int can_queue;
348
349 /*
350 * In many instances, especially where disconnect / reconnect are
351 * supported, our host also has an ID on the SCSI bus. If this is
352 * the case, then it must be reserved. Please set this_id to -1 if
353 * your setup is in single initiator mode, and the host lacks an
354 * ID.
355 */
356 int this_id;
357
358 /*
359 * This determines the degree to which the host adapter is capable
360 * of scatter-gather.
361 */
362 unsigned short sg_tablesize;
363 unsigned short sg_prot_tablesize;
364
365 /*
366 * Set this if the host adapter has limitations beside segment count.
367 */
368 unsigned int max_sectors;
369
370 /*
371 * Maximum size in bytes of a single segment.
372 */
373 unsigned int max_segment_size;
374
375 /*
376 * DMA scatter gather segment boundary limit. A segment crossing this
377 * boundary will be split in two.
378 */
379 unsigned long dma_boundary;
380
381 unsigned long virt_boundary_mask;
382
383 /*
384 * This specifies "machine infinity" for host templates which don't
385 * limit the transfer size. Note this limit represents an absolute
386 * maximum, and may be over the transfer limits allowed for
387 * individual devices (e.g. 256 for SCSI-1).
388 */
389#define SCSI_DEFAULT_MAX_SECTORS 1024
390
391 /*
392 * True if this host adapter can make good use of linked commands.
393 * This will allow more than one command to be queued to a given
394 * unit on a given host. Set this to the maximum number of command
395 * blocks to be provided for each device. Set this to 1 for one
396 * command block per lun, 2 for two, etc. Do not set this to 0.
397 * You should make sure that the host adapter will do the right thing
398 * before you try setting this above 1.
399 */
400 short cmd_per_lun;
401
402 /*
403 * present contains counter indicating how many boards of this
404 * type were found when we did the scan.
405 */
406 unsigned char present;
407
408 /* If use block layer to manage tags, this is tag allocation policy */
409 int tag_alloc_policy;
410
411 /*
412 * Track QUEUE_FULL events and reduce queue depth on demand.
413 */
414 unsigned track_queue_depth:1;
415
416 /*
417 * This specifies the mode that a LLD supports.
418 */
419 unsigned supported_mode:2;
420
421 /*
422 * True if this host adapter uses unchecked DMA onto an ISA bus.
423 */
424 unsigned unchecked_isa_dma:1;
425
426 /*
427 * True for emulated SCSI host adapters (e.g. ATAPI).
428 */
429 unsigned emulated:1;
430
431 /*
432 * True if the low-level driver performs its own reset-settle delays.
433 */
434 unsigned skip_settle_delay:1;
435
436 /* True if the controller does not support WRITE SAME */
437 unsigned no_write_same:1;
438
439 /*
440 * Countdown for host blocking with no commands outstanding.
441 */
442 unsigned int max_host_blocked;
443
444 /*
445 * Default value for the blocking. If the queue is empty,
446 * host_blocked counts down in the request_fn until it restarts
447 * host operations as zero is reached.
448 *
449 * FIXME: This should probably be a value in the template
450 */
451#define SCSI_DEFAULT_HOST_BLOCKED 7
452
453 /*
454 * Pointer to the sysfs class properties for this host, NULL terminated.
455 */
456 struct device_attribute **shost_attrs;
457
458 /*
459 * Pointer to the SCSI device properties for this host, NULL terminated.
460 */
461 struct device_attribute **sdev_attrs;
462
463 /*
464 * Pointer to the SCSI device attribute groups for this host,
465 * NULL terminated.
466 */
467 const struct attribute_group **sdev_groups;
468
469 /*
470 * Vendor Identifier associated with the host
471 *
472 * Note: When specifying vendor_id, be sure to read the
473 * Vendor Type and ID formatting requirements specified in
474 * scsi_netlink.h
475 */
476 u64 vendor_id;
477
478 /*
479 * Additional per-command data allocated for the driver.
480 */
481 unsigned int cmd_size;
482 struct scsi_host_cmd_pool *cmd_pool;
483
484 /* Delay for runtime autosuspend */
485 int rpm_autosuspend_delay;
486};
487
488/*
489 * Temporary #define for host lock push down. Can be removed when all
490 * drivers have been updated to take advantage of unlocked
491 * queuecommand.
492 *
493 */
494#define DEF_SCSI_QCMD(func_name) \
495 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
496 { \
497 unsigned long irq_flags; \
498 int rc; \
499 spin_lock_irqsave(shost->host_lock, irq_flags); \
500 rc = func_name##_lck (cmd, cmd->scsi_done); \
501 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
502 return rc; \
503 }
504
505
506/*
507 * shost state: If you alter this, you also need to alter scsi_sysfs.c
508 * (for the ascii descriptions) and the state model enforcer:
509 * scsi_host_set_state()
510 */
511enum scsi_host_state {
512 SHOST_CREATED = 1,
513 SHOST_RUNNING,
514 SHOST_CANCEL,
515 SHOST_DEL,
516 SHOST_RECOVERY,
517 SHOST_CANCEL_RECOVERY,
518 SHOST_DEL_RECOVERY,
519};
520
521struct Scsi_Host {
522 /*
523 * __devices is protected by the host_lock, but you should
524 * usually use scsi_device_lookup / shost_for_each_device
525 * to access it and don't care about locking yourself.
526 * In the rare case of being in irq context you can use
527 * their __ prefixed variants with the lock held. NEVER
528 * access this list directly from a driver.
529 */
530 struct list_head __devices;
531 struct list_head __targets;
532
533 struct list_head starved_list;
534
535 spinlock_t default_lock;
536 spinlock_t *host_lock;
537
538 struct mutex scan_mutex;/* serialize scanning activity */
539
540 struct list_head eh_cmd_q;
541 struct task_struct * ehandler; /* Error recovery thread. */
542 struct completion * eh_action; /* Wait for specific actions on the
543 host. */
544 wait_queue_head_t host_wait;
545 struct scsi_host_template *hostt;
546 struct scsi_transport_template *transportt;
547
548 /* Area to keep a shared tag map */
549 struct blk_mq_tag_set tag_set;
550
551 atomic_t host_blocked;
552
553 unsigned int host_failed; /* commands that failed.
554 protected by host_lock */
555 unsigned int host_eh_scheduled; /* EH scheduled without command */
556
557 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
558
559 /* next two fields are used to bound the time spent in error handling */
560 int eh_deadline;
561 unsigned long last_reset;
562
563
564 /*
565 * These three parameters can be used to allow for wide scsi,
566 * and for host adapters that support multiple busses
567 * The last two should be set to 1 more than the actual max id
568 * or lun (e.g. 8 for SCSI parallel systems).
569 */
570 unsigned int max_channel;
571 unsigned int max_id;
572 u64 max_lun;
573
574 /*
575 * This is a unique identifier that must be assigned so that we
576 * have some way of identifying each detected host adapter properly
577 * and uniquely. For hosts that do not support more than one card
578 * in the system at one time, this does not need to be set. It is
579 * initialized to 0 in scsi_register.
580 */
581 unsigned int unique_id;
582
583 /*
584 * The maximum length of SCSI commands that this host can accept.
585 * Probably 12 for most host adapters, but could be 16 for others.
586 * or 260 if the driver supports variable length cdbs.
587 * For drivers that don't set this field, a value of 12 is
588 * assumed.
589 */
590 unsigned short max_cmd_len;
591
592 int this_id;
593 int can_queue;
594 short cmd_per_lun;
595 short unsigned int sg_tablesize;
596 short unsigned int sg_prot_tablesize;
597 unsigned int max_sectors;
598 unsigned int max_segment_size;
599 unsigned long dma_boundary;
600 unsigned long virt_boundary_mask;
601 /*
602 * In scsi-mq mode, the number of hardware queues supported by the LLD.
603 *
604 * Note: it is assumed that each hardware queue has a queue depth of
605 * can_queue. In other words, the total queue depth per host
606 * is nr_hw_queues * can_queue.
607 */
608 unsigned nr_hw_queues;
609 unsigned active_mode:2;
610 unsigned unchecked_isa_dma:1;
611
612 /*
613 * Host has requested that no further requests come through for the
614 * time being.
615 */
616 unsigned host_self_blocked:1;
617
618 /*
619 * Host uses correct SCSI ordering not PC ordering. The bit is
620 * set for the minority of drivers whose authors actually read
621 * the spec ;).
622 */
623 unsigned reverse_ordering:1;
624
625 /* Task mgmt function in progress */
626 unsigned tmf_in_progress:1;
627
628 /* Asynchronous scan in progress */
629 unsigned async_scan:1;
630
631 /* Don't resume host in EH */
632 unsigned eh_noresume:1;
633
634 /* The controller does not support WRITE SAME */
635 unsigned no_write_same:1;
636
637 /* Host responded with short (<36 bytes) INQUIRY result */
638 unsigned short_inquiry:1;
639
640 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
641 unsigned no_scsi2_lun_in_cdb:1;
642
643 /*
644 * Optional work queue to be utilized by the transport
645 */
646 char work_q_name[20];
647 struct workqueue_struct *work_q;
648
649 /*
650 * Task management function work queue
651 */
652 struct workqueue_struct *tmf_work_q;
653
654 /*
655 * Value host_blocked counts down from
656 */
657 unsigned int max_host_blocked;
658
659 /* Protection Information */
660 unsigned int prot_capabilities;
661 unsigned char prot_guard_type;
662
663 /* legacy crap */
664 unsigned long base;
665 unsigned long io_port;
666 unsigned char n_io_port;
667 unsigned char dma_channel;
668 unsigned int irq;
669
670
671 enum scsi_host_state shost_state;
672
673 /* ldm bits */
674 struct device shost_gendev, shost_dev;
675
676 /*
677 * Points to the transport data (if any) which is allocated
678 * separately
679 */
680 void *shost_data;
681
682 /*
683 * Points to the physical bus device we'd use to do DMA
684 * Needed just in case we have virtual hosts.
685 */
686 struct device *dma_dev;
687
688 /*
689 * We should ensure that this is aligned, both for better performance
690 * and also because some compilers (m68k) don't automatically force
691 * alignment to a long boundary.
692 */
693 unsigned long hostdata[] /* Used for storage of host specific stuff */
694 __attribute__ ((aligned (sizeof(unsigned long))));
695};
696
697#define class_to_shost(d) \
698 container_of(d, struct Scsi_Host, shost_dev)
699
700#define shost_printk(prefix, shost, fmt, a...) \
701 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
702
703static inline void *shost_priv(struct Scsi_Host *shost)
704{
705 return (void *)shost->hostdata;
706}
707
708int scsi_is_host_device(const struct device *);
709
710static inline struct Scsi_Host *dev_to_shost(struct device *dev)
711{
712 while (!scsi_is_host_device(dev)) {
713 if (!dev->parent)
714 return NULL;
715 dev = dev->parent;
716 }
717 return container_of(dev, struct Scsi_Host, shost_gendev);
718}
719
720static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
721{
722 return shost->shost_state == SHOST_RECOVERY ||
723 shost->shost_state == SHOST_CANCEL_RECOVERY ||
724 shost->shost_state == SHOST_DEL_RECOVERY ||
725 shost->tmf_in_progress;
726}
727
728extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
729extern void scsi_flush_work(struct Scsi_Host *);
730
731extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
732extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
733 struct device *,
734 struct device *);
735extern void scsi_scan_host(struct Scsi_Host *);
736extern void scsi_rescan_device(struct device *);
737extern void scsi_remove_host(struct Scsi_Host *);
738extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
739extern int scsi_host_busy(struct Scsi_Host *shost);
740extern void scsi_host_put(struct Scsi_Host *t);
741extern struct Scsi_Host *scsi_host_lookup(unsigned short);
742extern const char *scsi_host_state_name(enum scsi_host_state);
743extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
744 int status);
745
746static inline int __must_check scsi_add_host(struct Scsi_Host *host,
747 struct device *dev)
748{
749 return scsi_add_host_with_dma(host, dev, dev);
750}
751
752static inline struct device *scsi_get_device(struct Scsi_Host *shost)
753{
754 return shost->shost_gendev.parent;
755}
756
757/**
758 * scsi_host_scan_allowed - Is scanning of this host allowed
759 * @shost: Pointer to Scsi_Host.
760 **/
761static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
762{
763 return shost->shost_state == SHOST_RUNNING ||
764 shost->shost_state == SHOST_RECOVERY;
765}
766
767extern void scsi_unblock_requests(struct Scsi_Host *);
768extern void scsi_block_requests(struct Scsi_Host *);
769extern int scsi_host_block(struct Scsi_Host *shost);
770extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
771
772void scsi_host_busy_iter(struct Scsi_Host *,
773 bool (*fn)(struct scsi_cmnd *, void *, bool), void *priv);
774
775struct class_container;
776
777/*
778 * These two functions are used to allocate and free a pseudo device
779 * which will connect to the host adapter itself rather than any
780 * physical device. You must deallocate when you are done with the
781 * thing. This physical pseudo-device isn't real and won't be available
782 * from any high-level drivers.
783 */
784extern void scsi_free_host_dev(struct scsi_device *);
785extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
786
787/*
788 * DIF defines the exchange of protection information between
789 * initiator and SBC block device.
790 *
791 * DIX defines the exchange of protection information between OS and
792 * initiator.
793 */
794enum scsi_host_prot_capabilities {
795 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
796 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
797 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
798
799 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
800 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
801 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
802 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
803};
804
805/*
806 * SCSI hosts which support the Data Integrity Extensions must
807 * indicate their capabilities by setting the prot_capabilities using
808 * this call.
809 */
810static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
811{
812 shost->prot_capabilities = mask;
813}
814
815static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
816{
817 return shost->prot_capabilities;
818}
819
820static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
821{
822 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
823}
824
825static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
826{
827 static unsigned char cap[] = { 0,
828 SHOST_DIF_TYPE1_PROTECTION,
829 SHOST_DIF_TYPE2_PROTECTION,
830 SHOST_DIF_TYPE3_PROTECTION };
831
832 if (target_type >= ARRAY_SIZE(cap))
833 return 0;
834
835 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
836}
837
838static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
839{
840#if defined(CONFIG_BLK_DEV_INTEGRITY)
841 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
842 SHOST_DIX_TYPE1_PROTECTION,
843 SHOST_DIX_TYPE2_PROTECTION,
844 SHOST_DIX_TYPE3_PROTECTION };
845
846 if (target_type >= ARRAY_SIZE(cap))
847 return 0;
848
849 return shost->prot_capabilities & cap[target_type];
850#endif
851 return 0;
852}
853
854/*
855 * All DIX-capable initiators must support the T10-mandated CRC
856 * checksum. Controllers can optionally implement the IP checksum
857 * scheme which has much lower impact on system performance. Note
858 * that the main rationale for the checksum is to match integrity
859 * metadata with data. Detecting bit errors are a job for ECC memory
860 * and buses.
861 */
862
863enum scsi_host_guard_type {
864 SHOST_DIX_GUARD_CRC = 1 << 0,
865 SHOST_DIX_GUARD_IP = 1 << 1,
866};
867
868static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
869{
870 shost->prot_guard_type = type;
871}
872
873static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
874{
875 return shost->prot_guard_type;
876}
877
878extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
879
880#endif /* _SCSI_SCSI_HOST_H */
1#ifndef _SCSI_SCSI_HOST_H
2#define _SCSI_SCSI_HOST_H
3
4#include <linux/device.h>
5#include <linux/list.h>
6#include <linux/types.h>
7#include <linux/workqueue.h>
8#include <linux/mutex.h>
9#include <linux/seq_file.h>
10#include <linux/blk-mq.h>
11#include <scsi/scsi.h>
12
13struct request_queue;
14struct block_device;
15struct completion;
16struct module;
17struct scsi_cmnd;
18struct scsi_device;
19struct scsi_host_cmd_pool;
20struct scsi_target;
21struct Scsi_Host;
22struct scsi_host_cmd_pool;
23struct scsi_transport_template;
24struct blk_queue_tags;
25
26
27/*
28 * The various choices mean:
29 * NONE: Self evident. Host adapter is not capable of scatter-gather.
30 * ALL: Means that the host adapter module can do scatter-gather,
31 * and that there is no limit to the size of the table to which
32 * we scatter/gather data. The value we set here is the maximum
33 * single element sglist. To use chained sglists, the adapter
34 * has to set a value beyond ALL (and correctly use the chain
35 * handling API.
36 * Anything else: Indicates the maximum number of chains that can be
37 * used in one scatter-gather request.
38 */
39#define SG_NONE 0
40#define SG_ALL SG_CHUNK_SIZE
41
42#define MODE_UNKNOWN 0x00
43#define MODE_INITIATOR 0x01
44#define MODE_TARGET 0x02
45
46#define DISABLE_CLUSTERING 0
47#define ENABLE_CLUSTERING 1
48
49struct scsi_host_template {
50 struct module *module;
51 const char *name;
52
53 /*
54 * Used to initialize old-style drivers. For new-style drivers
55 * just perform all work in your module initialization function.
56 *
57 * Status: OBSOLETE
58 */
59 int (* detect)(struct scsi_host_template *);
60
61 /*
62 * Used as unload callback for hosts with old-style drivers.
63 *
64 * Status: OBSOLETE
65 */
66 int (* release)(struct Scsi_Host *);
67
68 /*
69 * The info function will return whatever useful information the
70 * developer sees fit. If not provided, then the name field will
71 * be used instead.
72 *
73 * Status: OPTIONAL
74 */
75 const char *(* info)(struct Scsi_Host *);
76
77 /*
78 * Ioctl interface
79 *
80 * Status: OPTIONAL
81 */
82 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
83
84
85#ifdef CONFIG_COMPAT
86 /*
87 * Compat handler. Handle 32bit ABI.
88 * When unknown ioctl is passed return -ENOIOCTLCMD.
89 *
90 * Status: OPTIONAL
91 */
92 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
93#endif
94
95 /*
96 * The queuecommand function is used to queue up a scsi
97 * command block to the LLDD. When the driver finished
98 * processing the command the done callback is invoked.
99 *
100 * If queuecommand returns 0, then the HBA has accepted the
101 * command. The done() function must be called on the command
102 * when the driver has finished with it. (you may call done on the
103 * command before queuecommand returns, but in this case you
104 * *must* return 0 from queuecommand).
105 *
106 * Queuecommand may also reject the command, in which case it may
107 * not touch the command and must not call done() for it.
108 *
109 * There are two possible rejection returns:
110 *
111 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
112 * allow commands to other devices serviced by this host.
113 *
114 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
115 * host temporarily.
116 *
117 * For compatibility, any other non-zero return is treated the
118 * same as SCSI_MLQUEUE_HOST_BUSY.
119 *
120 * NOTE: "temporarily" means either until the next command for#
121 * this device/host completes, or a period of time determined by
122 * I/O pressure in the system if there are no other outstanding
123 * commands.
124 *
125 * STATUS: REQUIRED
126 */
127 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
128
129 /*
130 * This is an error handling strategy routine. You don't need to
131 * define one of these if you don't want to - there is a default
132 * routine that is present that should work in most cases. For those
133 * driver authors that have the inclination and ability to write their
134 * own strategy routine, this is where it is specified. Note - the
135 * strategy routine is *ALWAYS* run in the context of the kernel eh
136 * thread. Thus you are guaranteed to *NOT* be in an interrupt
137 * handler when you execute this, and you are also guaranteed to
138 * *NOT* have any other commands being queued while you are in the
139 * strategy routine. When you return from this function, operations
140 * return to normal.
141 *
142 * See scsi_error.c scsi_unjam_host for additional comments about
143 * what this function should and should not be attempting to do.
144 *
145 * Status: REQUIRED (at least one of them)
146 */
147 int (* eh_abort_handler)(struct scsi_cmnd *);
148 int (* eh_device_reset_handler)(struct scsi_cmnd *);
149 int (* eh_target_reset_handler)(struct scsi_cmnd *);
150 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
151 int (* eh_host_reset_handler)(struct scsi_cmnd *);
152
153 /*
154 * Before the mid layer attempts to scan for a new device where none
155 * currently exists, it will call this entry in your driver. Should
156 * your driver need to allocate any structs or perform any other init
157 * items in order to send commands to a currently unused target/lun
158 * combo, then this is where you can perform those allocations. This
159 * is specifically so that drivers won't have to perform any kind of
160 * "is this a new device" checks in their queuecommand routine,
161 * thereby making the hot path a bit quicker.
162 *
163 * Return values: 0 on success, non-0 on failure
164 *
165 * Deallocation: If we didn't find any devices at this ID, you will
166 * get an immediate call to slave_destroy(). If we find something
167 * here then you will get a call to slave_configure(), then the
168 * device will be used for however long it is kept around, then when
169 * the device is removed from the system (or * possibly at reboot
170 * time), you will then get a call to slave_destroy(). This is
171 * assuming you implement slave_configure and slave_destroy.
172 * However, if you allocate memory and hang it off the device struct,
173 * then you must implement the slave_destroy() routine at a minimum
174 * in order to avoid leaking memory
175 * each time a device is tore down.
176 *
177 * Status: OPTIONAL
178 */
179 int (* slave_alloc)(struct scsi_device *);
180
181 /*
182 * Once the device has responded to an INQUIRY and we know the
183 * device is online, we call into the low level driver with the
184 * struct scsi_device *. If the low level device driver implements
185 * this function, it *must* perform the task of setting the queue
186 * depth on the device. All other tasks are optional and depend
187 * on what the driver supports and various implementation details.
188 *
189 * Things currently recommended to be handled at this time include:
190 *
191 * 1. Setting the device queue depth. Proper setting of this is
192 * described in the comments for scsi_change_queue_depth.
193 * 2. Determining if the device supports the various synchronous
194 * negotiation protocols. The device struct will already have
195 * responded to INQUIRY and the results of the standard items
196 * will have been shoved into the various device flag bits, eg.
197 * device->sdtr will be true if the device supports SDTR messages.
198 * 3. Allocating command structs that the device will need.
199 * 4. Setting the default timeout on this device (if needed).
200 * 5. Anything else the low level driver might want to do on a device
201 * specific setup basis...
202 * 6. Return 0 on success, non-0 on error. The device will be marked
203 * as offline on error so that no access will occur. If you return
204 * non-0, your slave_destroy routine will never get called for this
205 * device, so don't leave any loose memory hanging around, clean
206 * up after yourself before returning non-0
207 *
208 * Status: OPTIONAL
209 */
210 int (* slave_configure)(struct scsi_device *);
211
212 /*
213 * Immediately prior to deallocating the device and after all activity
214 * has ceased the mid layer calls this point so that the low level
215 * driver may completely detach itself from the scsi device and vice
216 * versa. The low level driver is responsible for freeing any memory
217 * it allocated in the slave_alloc or slave_configure calls.
218 *
219 * Status: OPTIONAL
220 */
221 void (* slave_destroy)(struct scsi_device *);
222
223 /*
224 * Before the mid layer attempts to scan for a new device attached
225 * to a target where no target currently exists, it will call this
226 * entry in your driver. Should your driver need to allocate any
227 * structs or perform any other init items in order to send commands
228 * to a currently unused target, then this is where you can perform
229 * those allocations.
230 *
231 * Return values: 0 on success, non-0 on failure
232 *
233 * Status: OPTIONAL
234 */
235 int (* target_alloc)(struct scsi_target *);
236
237 /*
238 * Immediately prior to deallocating the target structure, and
239 * after all activity to attached scsi devices has ceased, the
240 * midlayer calls this point so that the driver may deallocate
241 * and terminate any references to the target.
242 *
243 * Status: OPTIONAL
244 */
245 void (* target_destroy)(struct scsi_target *);
246
247 /*
248 * If a host has the ability to discover targets on its own instead
249 * of scanning the entire bus, it can fill in this function and
250 * call scsi_scan_host(). This function will be called periodically
251 * until it returns 1 with the scsi_host and the elapsed time of
252 * the scan in jiffies.
253 *
254 * Status: OPTIONAL
255 */
256 int (* scan_finished)(struct Scsi_Host *, unsigned long);
257
258 /*
259 * If the host wants to be called before the scan starts, but
260 * after the midlayer has set up ready for the scan, it can fill
261 * in this function.
262 *
263 * Status: OPTIONAL
264 */
265 void (* scan_start)(struct Scsi_Host *);
266
267 /*
268 * Fill in this function to allow the queue depth of this host
269 * to be changeable (on a per device basis). Returns either
270 * the current queue depth setting (may be different from what
271 * was passed in) or an error. An error should only be
272 * returned if the requested depth is legal but the driver was
273 * unable to set it. If the requested depth is illegal, the
274 * driver should set and return the closest legal queue depth.
275 *
276 * Status: OPTIONAL
277 */
278 int (* change_queue_depth)(struct scsi_device *, int);
279
280 /*
281 * This functions lets the driver expose the queue mapping
282 * to the block layer.
283 *
284 * Status: OPTIONAL
285 */
286 int (* map_queues)(struct Scsi_Host *shost);
287
288 /*
289 * This function determines the BIOS parameters for a given
290 * harddisk. These tend to be numbers that are made up by
291 * the host adapter. Parameters:
292 * size, device, list (heads, sectors, cylinders)
293 *
294 * Status: OPTIONAL
295 */
296 int (* bios_param)(struct scsi_device *, struct block_device *,
297 sector_t, int []);
298
299 /*
300 * This function is called when one or more partitions on the
301 * device reach beyond the end of the device.
302 *
303 * Status: OPTIONAL
304 */
305 void (*unlock_native_capacity)(struct scsi_device *);
306
307 /*
308 * Can be used to export driver statistics and other infos to the
309 * world outside the kernel ie. userspace and it also provides an
310 * interface to feed the driver with information.
311 *
312 * Status: OBSOLETE
313 */
314 int (*show_info)(struct seq_file *, struct Scsi_Host *);
315 int (*write_info)(struct Scsi_Host *, char *, int);
316
317 /*
318 * This is an optional routine that allows the transport to become
319 * involved when a scsi io timer fires. The return value tells the
320 * timer routine how to finish the io timeout handling:
321 * EH_HANDLED: I fixed the error, please complete the command
322 * EH_RESET_TIMER: I need more time, reset the timer and
323 * begin counting again
324 * EH_NOT_HANDLED Begin normal error recovery
325 *
326 * Status: OPTIONAL
327 */
328 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
329
330 /* This is an optional routine that allows transport to initiate
331 * LLD adapter or firmware reset using sysfs attribute.
332 *
333 * Return values: 0 on success, -ve value on failure.
334 *
335 * Status: OPTIONAL
336 */
337
338 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
339#define SCSI_ADAPTER_RESET 1
340#define SCSI_FIRMWARE_RESET 2
341
342
343 /*
344 * Name of proc directory
345 */
346 const char *proc_name;
347
348 /*
349 * Used to store the procfs directory if a driver implements the
350 * show_info method.
351 */
352 struct proc_dir_entry *proc_dir;
353
354 /*
355 * This determines if we will use a non-interrupt driven
356 * or an interrupt driven scheme. It is set to the maximum number
357 * of simultaneous commands a given host adapter will accept.
358 */
359 int can_queue;
360
361 /*
362 * In many instances, especially where disconnect / reconnect are
363 * supported, our host also has an ID on the SCSI bus. If this is
364 * the case, then it must be reserved. Please set this_id to -1 if
365 * your setup is in single initiator mode, and the host lacks an
366 * ID.
367 */
368 int this_id;
369
370 /*
371 * This determines the degree to which the host adapter is capable
372 * of scatter-gather.
373 */
374 unsigned short sg_tablesize;
375 unsigned short sg_prot_tablesize;
376
377 /*
378 * Set this if the host adapter has limitations beside segment count.
379 */
380 unsigned int max_sectors;
381
382 /*
383 * DMA scatter gather segment boundary limit. A segment crossing this
384 * boundary will be split in two.
385 */
386 unsigned long dma_boundary;
387
388 /*
389 * This specifies "machine infinity" for host templates which don't
390 * limit the transfer size. Note this limit represents an absolute
391 * maximum, and may be over the transfer limits allowed for
392 * individual devices (e.g. 256 for SCSI-1).
393 */
394#define SCSI_DEFAULT_MAX_SECTORS 1024
395
396 /*
397 * True if this host adapter can make good use of linked commands.
398 * This will allow more than one command to be queued to a given
399 * unit on a given host. Set this to the maximum number of command
400 * blocks to be provided for each device. Set this to 1 for one
401 * command block per lun, 2 for two, etc. Do not set this to 0.
402 * You should make sure that the host adapter will do the right thing
403 * before you try setting this above 1.
404 */
405 short cmd_per_lun;
406
407 /*
408 * present contains counter indicating how many boards of this
409 * type were found when we did the scan.
410 */
411 unsigned char present;
412
413 /* If use block layer to manage tags, this is tag allocation policy */
414 int tag_alloc_policy;
415
416 /*
417 * Track QUEUE_FULL events and reduce queue depth on demand.
418 */
419 unsigned track_queue_depth:1;
420
421 /*
422 * This specifies the mode that a LLD supports.
423 */
424 unsigned supported_mode:2;
425
426 /*
427 * True if this host adapter uses unchecked DMA onto an ISA bus.
428 */
429 unsigned unchecked_isa_dma:1;
430
431 /*
432 * True if this host adapter can make good use of clustering.
433 * I originally thought that if the tablesize was large that it
434 * was a waste of CPU cycles to prepare a cluster list, but
435 * it works out that the Buslogic is faster if you use a smaller
436 * number of segments (i.e. use clustering). I guess it is
437 * inefficient.
438 */
439 unsigned use_clustering:1;
440
441 /*
442 * True for emulated SCSI host adapters (e.g. ATAPI).
443 */
444 unsigned emulated:1;
445
446 /*
447 * True if the low-level driver performs its own reset-settle delays.
448 */
449 unsigned skip_settle_delay:1;
450
451 /* True if the controller does not support WRITE SAME */
452 unsigned no_write_same:1;
453
454 /*
455 * True if asynchronous aborts are not supported
456 */
457 unsigned no_async_abort:1;
458
459 /*
460 * Countdown for host blocking with no commands outstanding.
461 */
462 unsigned int max_host_blocked;
463
464 /*
465 * Default value for the blocking. If the queue is empty,
466 * host_blocked counts down in the request_fn until it restarts
467 * host operations as zero is reached.
468 *
469 * FIXME: This should probably be a value in the template
470 */
471#define SCSI_DEFAULT_HOST_BLOCKED 7
472
473 /*
474 * Pointer to the sysfs class properties for this host, NULL terminated.
475 */
476 struct device_attribute **shost_attrs;
477
478 /*
479 * Pointer to the SCSI device properties for this host, NULL terminated.
480 */
481 struct device_attribute **sdev_attrs;
482
483 /*
484 * List of hosts per template.
485 *
486 * This is only for use by scsi_module.c for legacy templates.
487 * For these access to it is synchronized implicitly by
488 * module_init/module_exit.
489 */
490 struct list_head legacy_hosts;
491
492 /*
493 * Vendor Identifier associated with the host
494 *
495 * Note: When specifying vendor_id, be sure to read the
496 * Vendor Type and ID formatting requirements specified in
497 * scsi_netlink.h
498 */
499 u64 vendor_id;
500
501 /*
502 * Additional per-command data allocated for the driver.
503 */
504 unsigned int cmd_size;
505 struct scsi_host_cmd_pool *cmd_pool;
506};
507
508/*
509 * Temporary #define for host lock push down. Can be removed when all
510 * drivers have been updated to take advantage of unlocked
511 * 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 scsi_cmd_get_serial(shost, cmd); \
521 rc = func_name##_lck (cmd, cmd->scsi_done); \
522 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
523 return rc; \
524 }
525
526
527/*
528 * shost state: If you alter this, you also need to alter scsi_sysfs.c
529 * (for the ascii descriptions) and the state model enforcer:
530 * scsi_host_set_state()
531 */
532enum scsi_host_state {
533 SHOST_CREATED = 1,
534 SHOST_RUNNING,
535 SHOST_CANCEL,
536 SHOST_DEL,
537 SHOST_RECOVERY,
538 SHOST_CANCEL_RECOVERY,
539 SHOST_DEL_RECOVERY,
540};
541
542struct Scsi_Host {
543 /*
544 * __devices is protected by the host_lock, but you should
545 * usually use scsi_device_lookup / shost_for_each_device
546 * to access it and don't care about locking yourself.
547 * In the rare case of being in irq context you can use
548 * their __ prefixed variants with the lock held. NEVER
549 * access this list directly from a driver.
550 */
551 struct list_head __devices;
552 struct list_head __targets;
553
554 struct scsi_host_cmd_pool *cmd_pool;
555 spinlock_t free_list_lock;
556 struct list_head free_list; /* backup store of cmd structs */
557 struct list_head starved_list;
558
559 spinlock_t default_lock;
560 spinlock_t *host_lock;
561
562 struct mutex scan_mutex;/* serialize scanning activity */
563
564 struct list_head eh_cmd_q;
565 struct task_struct * ehandler; /* Error recovery thread. */
566 struct completion * eh_action; /* Wait for specific actions on the
567 host. */
568 wait_queue_head_t host_wait;
569 struct scsi_host_template *hostt;
570 struct scsi_transport_template *transportt;
571
572 /*
573 * Area to keep a shared tag map (if needed, will be
574 * NULL if not).
575 */
576 union {
577 struct blk_queue_tag *bqt;
578 struct blk_mq_tag_set tag_set;
579 };
580
581 atomic_t host_busy; /* commands actually active on low-level */
582 atomic_t host_blocked;
583
584 unsigned int host_failed; /* commands that failed.
585 protected by host_lock */
586 unsigned int host_eh_scheduled; /* EH scheduled without command */
587
588 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
589
590 /* next two fields are used to bound the time spent in error handling */
591 int eh_deadline;
592 unsigned long last_reset;
593
594
595 /*
596 * These three parameters can be used to allow for wide scsi,
597 * and for host adapters that support multiple busses
598 * The last two should be set to 1 more than the actual max id
599 * or lun (e.g. 8 for SCSI parallel systems).
600 */
601 unsigned int max_channel;
602 unsigned int max_id;
603 u64 max_lun;
604
605 /*
606 * This is a unique identifier that must be assigned so that we
607 * have some way of identifying each detected host adapter properly
608 * and uniquely. For hosts that do not support more than one card
609 * in the system at one time, this does not need to be set. It is
610 * initialized to 0 in scsi_register.
611 */
612 unsigned int unique_id;
613
614 /*
615 * The maximum length of SCSI commands that this host can accept.
616 * Probably 12 for most host adapters, but could be 16 for others.
617 * or 260 if the driver supports variable length cdbs.
618 * For drivers that don't set this field, a value of 12 is
619 * assumed.
620 */
621 unsigned short max_cmd_len;
622
623 int this_id;
624 int can_queue;
625 short cmd_per_lun;
626 short unsigned int sg_tablesize;
627 short unsigned int sg_prot_tablesize;
628 unsigned int max_sectors;
629 unsigned long dma_boundary;
630 /*
631 * In scsi-mq mode, the number of hardware queues supported by the LLD.
632 *
633 * Note: it is assumed that each hardware queue has a queue depth of
634 * can_queue. In other words, the total queue depth per host
635 * is nr_hw_queues * can_queue.
636 */
637 unsigned nr_hw_queues;
638 /*
639 * Used to assign serial numbers to the cmds.
640 * Protected by the host lock.
641 */
642 unsigned long cmd_serial_number;
643
644 unsigned active_mode:2;
645 unsigned unchecked_isa_dma:1;
646 unsigned use_clustering:1;
647
648 /*
649 * Host has requested that no further requests come through for the
650 * time being.
651 */
652 unsigned host_self_blocked:1;
653
654 /*
655 * Host uses correct SCSI ordering not PC ordering. The bit is
656 * set for the minority of drivers whose authors actually read
657 * the spec ;).
658 */
659 unsigned reverse_ordering:1;
660
661 /* Task mgmt function in progress */
662 unsigned tmf_in_progress:1;
663
664 /* Asynchronous scan in progress */
665 unsigned async_scan:1;
666
667 /* Don't resume host in EH */
668 unsigned eh_noresume:1;
669
670 /* The controller does not support WRITE SAME */
671 unsigned no_write_same:1;
672
673 unsigned use_blk_mq:1;
674 unsigned use_cmd_list:1;
675
676 /* Host responded with short (<36 bytes) INQUIRY result */
677 unsigned short_inquiry:1;
678
679 /*
680 * Optional work queue to be utilized by the transport
681 */
682 char work_q_name[20];
683 struct workqueue_struct *work_q;
684
685 /*
686 * Task management function work queue
687 */
688 struct workqueue_struct *tmf_work_q;
689
690 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
691 unsigned no_scsi2_lun_in_cdb:1;
692
693 /*
694 * Value host_blocked counts down from
695 */
696 unsigned int max_host_blocked;
697
698 /* Protection Information */
699 unsigned int prot_capabilities;
700 unsigned char prot_guard_type;
701
702 /*
703 * q used for scsi_tgt msgs, async events or any other requests that
704 * need to be processed in userspace
705 */
706 struct request_queue *uspace_req_q;
707
708 /* legacy crap */
709 unsigned long base;
710 unsigned long io_port;
711 unsigned char n_io_port;
712 unsigned char dma_channel;
713 unsigned int irq;
714
715
716 enum scsi_host_state shost_state;
717
718 /* ldm bits */
719 struct device shost_gendev, shost_dev;
720
721 /*
722 * List of hosts per template.
723 *
724 * This is only for use by scsi_module.c for legacy templates.
725 * For these access to it is synchronized implicitly by
726 * module_init/module_exit.
727 */
728 struct list_head sht_legacy_list;
729
730 /*
731 * Points to the transport data (if any) which is allocated
732 * separately
733 */
734 void *shost_data;
735
736 /*
737 * Points to the physical bus device we'd use to do DMA
738 * Needed just in case we have virtual hosts.
739 */
740 struct device *dma_dev;
741
742 /*
743 * We should ensure that this is aligned, both for better performance
744 * and also because some compilers (m68k) don't automatically force
745 * alignment to a long boundary.
746 */
747 unsigned long hostdata[0] /* Used for storage of host specific stuff */
748 __attribute__ ((aligned (sizeof(unsigned long))));
749};
750
751#define class_to_shost(d) \
752 container_of(d, struct Scsi_Host, shost_dev)
753
754#define shost_printk(prefix, shost, fmt, a...) \
755 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
756
757static inline void *shost_priv(struct Scsi_Host *shost)
758{
759 return (void *)shost->hostdata;
760}
761
762int scsi_is_host_device(const struct device *);
763
764static inline struct Scsi_Host *dev_to_shost(struct device *dev)
765{
766 while (!scsi_is_host_device(dev)) {
767 if (!dev->parent)
768 return NULL;
769 dev = dev->parent;
770 }
771 return container_of(dev, struct Scsi_Host, shost_gendev);
772}
773
774static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
775{
776 return shost->shost_state == SHOST_RECOVERY ||
777 shost->shost_state == SHOST_CANCEL_RECOVERY ||
778 shost->shost_state == SHOST_DEL_RECOVERY ||
779 shost->tmf_in_progress;
780}
781
782static inline bool shost_use_blk_mq(struct Scsi_Host *shost)
783{
784 return shost->use_blk_mq;
785}
786
787extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
788extern void scsi_flush_work(struct Scsi_Host *);
789
790extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
791extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
792 struct device *,
793 struct device *);
794extern void scsi_scan_host(struct Scsi_Host *);
795extern void scsi_rescan_device(struct device *);
796extern void scsi_remove_host(struct Scsi_Host *);
797extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
798extern void scsi_host_put(struct Scsi_Host *t);
799extern struct Scsi_Host *scsi_host_lookup(unsigned short);
800extern const char *scsi_host_state_name(enum scsi_host_state);
801extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *);
802
803static inline int __must_check scsi_add_host(struct Scsi_Host *host,
804 struct device *dev)
805{
806 return scsi_add_host_with_dma(host, dev, dev);
807}
808
809static inline struct device *scsi_get_device(struct Scsi_Host *shost)
810{
811 return shost->shost_gendev.parent;
812}
813
814/**
815 * scsi_host_scan_allowed - Is scanning of this host allowed
816 * @shost: Pointer to Scsi_Host.
817 **/
818static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
819{
820 return shost->shost_state == SHOST_RUNNING ||
821 shost->shost_state == SHOST_RECOVERY;
822}
823
824extern void scsi_unblock_requests(struct Scsi_Host *);
825extern void scsi_block_requests(struct Scsi_Host *);
826
827struct class_container;
828
829extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
830 void (*) (struct request_queue *));
831/*
832 * These two functions are used to allocate and free a pseudo device
833 * which will connect to the host adapter itself rather than any
834 * physical device. You must deallocate when you are done with the
835 * thing. This physical pseudo-device isn't real and won't be available
836 * from any high-level drivers.
837 */
838extern void scsi_free_host_dev(struct scsi_device *);
839extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
840
841/*
842 * DIF defines the exchange of protection information between
843 * initiator and SBC block device.
844 *
845 * DIX defines the exchange of protection information between OS and
846 * initiator.
847 */
848enum scsi_host_prot_capabilities {
849 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
850 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
851 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
852
853 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
854 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
855 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
856 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
857};
858
859/*
860 * SCSI hosts which support the Data Integrity Extensions must
861 * indicate their capabilities by setting the prot_capabilities using
862 * this call.
863 */
864static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
865{
866 shost->prot_capabilities = mask;
867}
868
869static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
870{
871 return shost->prot_capabilities;
872}
873
874static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
875{
876 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
877}
878
879static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
880{
881 static unsigned char cap[] = { 0,
882 SHOST_DIF_TYPE1_PROTECTION,
883 SHOST_DIF_TYPE2_PROTECTION,
884 SHOST_DIF_TYPE3_PROTECTION };
885
886 if (target_type >= ARRAY_SIZE(cap))
887 return 0;
888
889 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
890}
891
892static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
893{
894#if defined(CONFIG_BLK_DEV_INTEGRITY)
895 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
896 SHOST_DIX_TYPE1_PROTECTION,
897 SHOST_DIX_TYPE2_PROTECTION,
898 SHOST_DIX_TYPE3_PROTECTION };
899
900 if (target_type >= ARRAY_SIZE(cap))
901 return 0;
902
903 return shost->prot_capabilities & cap[target_type];
904#endif
905 return 0;
906}
907
908/*
909 * All DIX-capable initiators must support the T10-mandated CRC
910 * checksum. Controllers can optionally implement the IP checksum
911 * scheme which has much lower impact on system performance. Note
912 * that the main rationale for the checksum is to match integrity
913 * metadata with data. Detecting bit errors are a job for ECC memory
914 * and buses.
915 */
916
917enum scsi_host_guard_type {
918 SHOST_DIX_GUARD_CRC = 1 << 0,
919 SHOST_DIX_GUARD_IP = 1 << 1,
920};
921
922static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
923{
924 shost->prot_guard_type = type;
925}
926
927static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
928{
929 return shost->prot_guard_type;
930}
931
932/* legacy interfaces */
933extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
934extern void scsi_unregister(struct Scsi_Host *);
935extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
936
937#endif /* _SCSI_SCSI_HOST_H */