Merge patch series "convert SCSI to atomic queue limits, part 1 (v3)"
[linux-block.git] / include / scsi / scsi_host.h
CommitLineData
b2441318 1/* SPDX-License-Identifier: GPL-2.0 */
1da177e4
LT
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>
0b950672 9#include <linux/mutex.h>
0ffddfbb 10#include <linux/seq_file.h>
d285203c 11#include <linux/blk-mq.h>
4660c8ed 12#include <scsi/scsi.h>
1da177e4
LT
13
14struct block_device;
7dfdc9a5 15struct completion;
1da177e4
LT
16struct module;
17struct scsi_cmnd;
18struct scsi_device;
a283bd37 19struct scsi_target;
1da177e4 20struct Scsi_Host;
1da177e4
LT
21struct scsi_transport_template;
22
23
65e8617f 24#define SG_ALL SG_CHUNK_SIZE
1da177e4 25
5dc2b89e
FT
26#define MODE_UNKNOWN 0x00
27#define MODE_INITIATOR 0x01
28#define MODE_TARGET 0x02
1da177e4 29
dee7121e
BVA
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
1da177e4 42struct scsi_host_template {
1da177e4 43 /*
9ebb4d70
ML
44 * Put fields referenced in IO submission path together in
45 * same cacheline
1da177e4 46 */
1da177e4
LT
47
48 /*
9ebb4d70 49 * Additional per-command data allocated for the driver.
1da177e4 50 */
9ebb4d70 51 unsigned int cmd_size;
65ca846a 52
1da177e4
LT
53 /*
54 * The queuecommand function is used to queue up a scsi
55 * command block to the LLDD. When the driver finished
56 * processing the command the done callback is invoked.
57 *
8930a6c2
PB
58 * If queuecommand returns 0, then the driver has accepted the
59 * command. It must also push it to the HBA if the scsi_cmnd
60 * flag SCMD_LAST is set, or if the driver does not implement
61 * commit_rqs. The done() function must be called on the command
1da177e4
LT
62 * when the driver has finished with it. (you may call done on the
63 * command before queuecommand returns, but in this case you
64 * *must* return 0 from queuecommand).
65 *
66 * Queuecommand may also reject the command, in which case it may
67 * 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, but
72 * allow commands to other devices serviced by this host.
73 *
74 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
75 * host temporarily.
76 *
77 * For compatibility, any other non-zero return is treated the
78 * 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 by
82 * I/O pressure in the system if there are no other outstanding
83 * commands.
84 *
85 * STATUS: REQUIRED
86 */
f281233d 87 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
1da177e4 88
8930a6c2
PB
89 /*
90 * The commit_rqs function is used to trigger a hardware
91 * doorbell after some requests have been queued with
92 * queuecommand, when an error is encountered before sending
93 * the request with SCMD_LAST set.
94 *
95 * STATUS: OPTIONAL
96 */
97 void (*commit_rqs)(struct Scsi_Host *, u16);
98
9ebb4d70
ML
99 struct module *module;
100 const char *name;
101
102 /*
103 * The info function will return whatever useful information the
104 * developer sees fit. If not provided, then the name field will
105 * be used instead.
106 *
107 * Status: OPTIONAL
108 */
109 const char *(*info)(struct Scsi_Host *);
110
111 /*
112 * Ioctl interface
113 *
114 * Status: OPTIONAL
115 */
116 int (*ioctl)(struct scsi_device *dev, unsigned int cmd,
117 void __user *arg);
118
119
120#ifdef CONFIG_COMPAT
121 /*
122 * Compat handler. Handle 32bit ABI.
123 * When unknown ioctl is passed return -ENOIOCTLCMD.
124 *
125 * Status: OPTIONAL
126 */
127 int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,
128 void __user *arg);
129#endif
130
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
1da177e4
LT
134 /*
135 * This is an error handling strategy routine. You don't need to
136 * define one of these if you don't want to - there is a default
137 * routine that is present that should work in most cases. For those
138 * driver authors that have the inclination and ability to write their
139 * own strategy routine, this is where it is specified. Note - the
140 * strategy routine is *ALWAYS* run in the context of the kernel eh
141 * thread. Thus you are guaranteed to *NOT* be in an interrupt
142 * handler when you execute this, and you are also guaranteed to
143 * *NOT* have any other commands being queued while you are in the
144 * strategy routine. When you return from this function, operations
145 * return to normal.
146 *
147 * See scsi_error.c scsi_unjam_host for additional comments about
148 * what this function should and should not be attempting to do.
149 *
150 * Status: REQUIRED (at least one of them)
151 */
1da177e4
LT
152 int (* eh_abort_handler)(struct scsi_cmnd *);
153 int (* eh_device_reset_handler)(struct scsi_cmnd *);
30bd7df8 154 int (* eh_target_reset_handler)(struct scsi_cmnd *);
1da177e4
LT
155 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
156 int (* eh_host_reset_handler)(struct scsi_cmnd *);
157
1da177e4
LT
158 /*
159 * Before the mid layer attempts to scan for a new device where none
160 * currently exists, it will call this entry in your driver. Should
161 * your driver need to allocate any structs or perform any other init
162 * items in order to send commands to a currently unused target/lun
163 * combo, then this is where you can perform those allocations. This
164 * is specifically so that drivers won't have to perform any kind of
165 * "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 failure
169 *
170 * Deallocation: If we didn't find any devices at this ID, you will
171 * get an immediate call to slave_destroy(). If we find something
172 * here then you will get a call to slave_configure(), then the
173 * device will be used for however long it is kept around, then when
174 * the device is removed from the system (or * possibly at reboot
175 * time), you will then get a call to slave_destroy(). This is
176 * 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 minimum
179 * in order to avoid leaking memory
180 * each time a device is tore down.
181 *
182 * Status: OPTIONAL
183 */
184 int (* slave_alloc)(struct scsi_device *);
185
186 /*
187 * Once the device has responded to an INQUIRY and we know the
188 * device is online, we call into the low level driver with the
189 * struct scsi_device *. If the low level device driver implements
190 * this function, it *must* perform the task of setting the queue
191 * depth on the device. All other tasks are optional and depend
192 * 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 is
db5ed4df 197 * described in the comments for scsi_change_queue_depth.
1da177e4
LT
198 * 2. Determining if the device supports the various synchronous
199 * negotiation protocols. The device struct will already have
200 * responded to INQUIRY and the results of the standard items
201 * 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 device
206 * specific setup basis...
207 * 6. Return 0 on success, non-0 on error. The device will be marked
208 * as offline on error so that no access will occur. If you return
209 * non-0, your slave_destroy routine will never get called for this
210 * device, so don't leave any loose memory hanging around, clean
211 * up after yourself before returning non-0
212 *
213 * Status: OPTIONAL
b7eefcf1
CH
214 *
215 * Note: slave_configure is the legacy version, use device_configure for
216 * all new code. A driver must never define both.
1da177e4 217 */
b7eefcf1 218 int (* device_configure)(struct scsi_device *, struct queue_limits *lim);
1da177e4
LT
219 int (* slave_configure)(struct scsi_device *);
220
221 /*
222 * Immediately prior to deallocating the device and after all activity
223 * has ceased the mid layer calls this point so that the low level
224 * driver may completely detach itself from the scsi device and vice
225 * versa. The low level driver is responsible for freeing any memory
226 * it allocated in the slave_alloc or slave_configure calls.
227 *
228 * Status: OPTIONAL
229 */
230 void (* slave_destroy)(struct scsi_device *);
231
a283bd37
JB
232 /*
233 * Before the mid layer attempts to scan for a new device attached
234 * to a target where no target currently exists, it will call this
235 * entry in your driver. Should your driver need to allocate any
236 * structs or perform any other init items in order to send commands
237 * to a currently unused target, then this is where you can perform
238 * those allocations.
239 *
240 * Return values: 0 on success, non-0 on failure
241 *
242 * Status: OPTIONAL
243 */
244 int (* target_alloc)(struct scsi_target *);
245
246 /*
247 * Immediately prior to deallocating the target structure, and
248 * after all activity to attached scsi devices has ceased, the
249 * midlayer calls this point so that the driver may deallocate
250 * and terminate any references to the target.
251 *
82f52b2c
WH
252 * Note: This callback is called with the host lock held and hence
253 * must not sleep.
254 *
a283bd37
JB
255 * Status: OPTIONAL
256 */
257 void (* target_destroy)(struct scsi_target *);
258
1aa8fab2
MW
259 /*
260 * If a host has the ability to discover targets on its own instead
261 * of scanning the entire bus, it can fill in this function and
262 * call scsi_scan_host(). This function will be called periodically
263 * until it returns 1 with the scsi_host and the elapsed time of
264 * the scan in jiffies.
265 *
266 * Status: OPTIONAL
267 */
268 int (* scan_finished)(struct Scsi_Host *, unsigned long);
269
270 /*
271 * If the host wants to be called before the scan starts, but
272 * after the midlayer has set up ready for the scan, it can fill
273 * in this function.
d850bd34
PM
274 *
275 * Status: OPTIONAL
1aa8fab2
MW
276 */
277 void (* scan_start)(struct Scsi_Host *);
278
1da177e4 279 /*
d850bd34
PM
280 * Fill in this function to allow the queue depth of this host
281 * to be changeable (on a per device basis). Returns either
1da177e4
LT
282 * the current queue depth setting (may be different from what
283 * was passed in) or an error. An error should only be
284 * returned if the requested depth is legal but the driver was
285 * unable to set it. If the requested depth is illegal, the
286 * driver should set and return the closest legal queue depth.
287 *
d850bd34 288 * Status: OPTIONAL
1da177e4 289 */
db5ed4df 290 int (* change_queue_depth)(struct scsi_device *, int);
1da177e4 291
2d9c5c20
CH
292 /*
293 * This functions lets the driver expose the queue mapping
294 * to the block layer.
295 *
296 * Status: OPTIONAL
297 */
a4e1d0b7 298 void (* map_queues)(struct Scsi_Host *shost);
2d9c5c20 299
af183095
KD
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: OPTIONAL
307 */
308 int (* mq_poll)(struct Scsi_Host *shost, unsigned int queue_num);
309
cc97923a
CH
310 /*
311 * Check if scatterlists need to be padded for DMA draining.
312 *
313 * Status: OPTIONAL
314 */
315 bool (* dma_need_drain)(struct request *rq);
316
1da177e4 317 /*
d850bd34 318 * This function determines the BIOS parameters for a given
1da177e4
LT
319 * harddisk. These tend to be numbers that are made up by
320 * the host adapter. Parameters:
321 * size, device, list (heads, sectors, cylinders)
322 *
d850bd34
PM
323 * Status: OPTIONAL
324 */
1da177e4
LT
325 int (* bios_param)(struct scsi_device *, struct block_device *,
326 sector_t, int []);
327
72ec24bd
TH
328 /*
329 * This function is called when one or more partitions on the
330 * device reach beyond the end of the device.
331 *
332 * Status: OPTIONAL
333 */
334 void (*unlock_native_capacity)(struct scsi_device *);
335
1da177e4
LT
336 /*
337 * Can be used to export driver statistics and other infos to the
338 * world outside the kernel ie. userspace and it also provides an
339 * interface to feed the driver with information.
340 *
341 * Status: OBSOLETE
342 */
0ffddfbb
AV
343 int (*show_info)(struct seq_file *, struct Scsi_Host *);
344 int (*write_info)(struct Scsi_Host *, char *, int);
1da177e4 345
6c5f8ce1
JB
346 /*
347 * This is an optional routine that allows the transport to become
348 * involved when a scsi io timer fires. The return value tells the
82c10ac7 349 * timer routine how to finish the io timeout handling.
6c5f8ce1
JB
350 *
351 * Status: OPTIONAL
352 */
dee7121e 353 enum scsi_timeout_action (*eh_timed_out)(struct scsi_cmnd *);
60bee27b
MK
354 /*
355 * Optional routine that allows the transport to decide if a cmd
356 * is retryable. Return true if the transport is in a state the
357 * cmd should be retried on.
358 */
359 bool (*eh_should_retry_cmd)(struct scsi_cmnd *scmd);
6c5f8ce1 360
29443691
VC
361 /* This is an optional routine that allows transport to initiate
362 * LLD adapter or firmware reset using sysfs attribute.
363 *
364 * Return values: 0 on success, -ve value on failure.
365 *
366 * Status: OPTIONAL
367 */
368
369 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
370#define SCSI_ADAPTER_RESET 1
371#define SCSI_FIRMWARE_RESET 2
372
373
1da177e4
LT
374 /*
375 * Name of proc directory
376 */
b02b6bc4 377 const char *proc_name;
1da177e4 378
1da177e4
LT
379 /*
380 * This determines if we will use a non-interrupt driven
d850bd34 381 * or an interrupt driven scheme. It is set to the maximum number
6eb045e0 382 * of simultaneous commands a single hw queue in HBA will accept.
1da177e4
LT
383 */
384 int can_queue;
385
386 /*
387 * In many instances, especially where disconnect / reconnect are
388 * supported, our host also has an ID on the SCSI bus. If this is
389 * the case, then it must be reserved. Please set this_id to -1 if
390 * your setup is in single initiator mode, and the host lacks an
391 * ID.
392 */
393 int this_id;
394
395 /*
396 * This determines the degree to which the host adapter is capable
397 * of scatter-gather.
398 */
399 unsigned short sg_tablesize;
13f05c8d 400 unsigned short sg_prot_tablesize;
1da177e4
LT
401
402 /*
d850bd34 403 * Set this if the host adapter has limitations beside segment count.
1da177e4 404 */
8ed5a4d2 405 unsigned int max_sectors;
1da177e4 406
50c2e910
CH
407 /*
408 * Maximum size in bytes of a single segment.
409 */
410 unsigned int max_segment_size;
411
5b7dfbef
CH
412 unsigned int dma_alignment;
413
1da177e4 414 /*
d850bd34 415 * DMA scatter gather segment boundary limit. A segment crossing this
1da177e4
LT
416 * boundary will be split in two.
417 */
418 unsigned long dma_boundary;
419
7ad388d8
CH
420 unsigned long virt_boundary_mask;
421
1da177e4
LT
422 /*
423 * This specifies "machine infinity" for host templates which don't
424 * limit the transfer size. Note this limit represents an absolute
425 * maximum, and may be over the transfer limits allowed for
d850bd34 426 * individual devices (e.g. 256 for SCSI-1).
1da177e4
LT
427 */
428#define SCSI_DEFAULT_MAX_SECTORS 1024
429
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 given
433 * unit on a given host. Set this to the maximum number of command
434 * blocks to be provided for each device. Set this to 1 for one
435 * 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 thing
437 * before you try setting this above 1.
438 */
439 short cmd_per_lun;
440
ee1b6f7a
SL
441 /* If use block layer to manage tags, this is tag allocation policy */
442 int tag_alloc_policy;
443
c40ecc12
CH
444 /*
445 * Track QUEUE_FULL events and reduce queue depth on demand.
446 */
447 unsigned track_queue_depth:1;
448
5dc2b89e
FT
449 /*
450 * This specifies the mode that a LLD supports.
451 */
452 unsigned supported_mode:2;
453
1da177e4 454 /*
d850bd34 455 * True for emulated SCSI host adapters (e.g. ATAPI).
1da177e4
LT
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
54b2b50c
MP
464 /* True if the controller does not support WRITE SAME */
465 unsigned no_write_same:1;
2f31115e 466
bdb01301
HR
467 /* True if the host uses host-wide tagspace */
468 unsigned host_tagset:1;
469
b125bb99
BVA
470 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
471 unsigned queuecommand_may_block:1;
472
1da177e4 473 /*
d850bd34 474 * Countdown for host blocking with no commands outstanding.
1da177e4
LT
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 restarts
481 * host operations as zero is reached.
482 *
483 * FIXME: This should probably be a value in the template
484 */
485#define SCSI_DEFAULT_HOST_BLOCKED 7
486
92c4b58b
BVA
487 /*
488 * Pointer to the SCSI host sysfs attribute groups, NULL terminated.
489 */
490 const struct attribute_group **shost_groups;
491
86b87cde
SN
492 /*
493 * Pointer to the SCSI device attribute groups for this host,
494 * NULL terminated.
495 */
496 const struct attribute_group **sdev_groups;
497
9e4f5e29
JS
498 /*
499 * Vendor Identifier associated with the host
500 *
501 * Note: When specifying vendor_id, be sure to read the
502 * Vendor Type and ID formatting requirements specified in
503 * scsi_netlink.h
504 */
505 u64 vendor_id;
1da177e4
LT
506};
507
f281233d
JG
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); \
af049dfd 520 rc = func_name##_lck(cmd); \
f281233d
JG
521 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
522 return rc; \
523 }
524
525
1da177e4 526/*
d3301874
MA
527 * shost state: If you alter this, you also need to alter scsi_sysfs.c
528 * (for the ascii descriptions) and the state model enforcer:
529 * scsi_host_set_state()
1da177e4 530 */
d3301874
MA
531enum scsi_host_state {
532 SHOST_CREATED = 1,
533 SHOST_RUNNING,
1da177e4 534 SHOST_CANCEL,
d3301874 535 SHOST_DEL,
1da177e4 536 SHOST_RECOVERY,
939647ee
JB
537 SHOST_CANCEL_RECOVERY,
538 SHOST_DEL_RECOVERY,
1da177e4
LT
539};
540
541struct Scsi_Host {
542 /*
543 * __devices is protected by the host_lock, but you should
544 * usually use scsi_device_lookup / shost_for_each_device
545 * to access it and don't care about locking yourself.
542cb459 546 * In the rare case of being in irq context you can use
1da177e4
LT
547 * their __ prefixed variants with the lock held. NEVER
548 * access this list directly from a driver.
549 */
550 struct list_head __devices;
551 struct list_head __targets;
552
1da177e4
LT
553 struct list_head starved_list;
554
555 spinlock_t default_lock;
556 spinlock_t *host_lock;
557
0b950672 558 struct mutex scan_mutex;/* serialize scanning activity */
1da177e4 559
5ae17501 560 struct list_head eh_abort_list;
1da177e4
LT
561 struct list_head eh_cmd_q;
562 struct task_struct * ehandler; /* Error recovery thread. */
7dfdc9a5
CH
563 struct completion * eh_action; /* Wait for specific actions on the
564 host. */
1da177e4 565 wait_queue_head_t host_wait;
e0d3f2c6 566 const struct scsi_host_template *hostt;
1da177e4 567 struct scsi_transport_template *transportt;
06f81ea8 568
8fe4ce58
BVA
569 struct kref tagset_refcnt;
570 struct completion tagset_freed;
f664a3cc
JA
571 /* Area to keep a shared tag map */
572 struct blk_mq_tag_set tag_set;
86e33a29 573
cd9070c9
CH
574 atomic_t host_blocked;
575
74665016
CH
576 unsigned int host_failed; /* commands that failed.
577 protected by host_lock */
ee7863bc 578 unsigned int host_eh_scheduled; /* EH scheduled without command */
1da177e4 579
6d49f63b 580 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
1da177e4 581
b4562022
HR
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
1da177e4
LT
587 /*
588 * These three parameters can be used to allow for wide scsi,
589 * and for host adapters that support multiple busses
8e4a5da6 590 * The last two should be set to 1 more than the actual max id
1abf635d 591 * or lun (e.g. 8 for SCSI parallel systems).
1da177e4 592 */
1da177e4 593 unsigned int max_channel;
1abf635d
HR
594 unsigned int max_id;
595 u64 max_lun;
1da177e4
LT
596
597 /*
598 * This is a unique identifier that must be assigned so that we
599 * have some way of identifying each detected host adapter properly
600 * and uniquely. For hosts that do not support more than one card
601 * in the system at one time, this does not need to be set. It is
602 * 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.
db4742dd 609 * or 260 if the driver supports variable length cdbs.
1da177e4 610 * For drivers that don't set this field, a value of 12 is
db4742dd 611 * assumed.
1da177e4 612 */
db4742dd 613 unsigned short max_cmd_len;
1da177e4
LT
614
615 int this_id;
616 int can_queue;
617 short cmd_per_lun;
618 short unsigned int sg_tablesize;
13f05c8d 619 short unsigned int sg_prot_tablesize;
8ed5a4d2 620 unsigned int max_sectors;
608128d3 621 unsigned int opt_sectors;
50c2e910 622 unsigned int max_segment_size;
5b7dfbef 623 unsigned int dma_alignment;
1da177e4 624 unsigned long dma_boundary;
7ad388d8 625 unsigned long virt_boundary_mask;
efec4b90
BVA
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 of
630 * can_queue. In other words, the total queue depth per host
bdb01301
HR
631 * is nr_hw_queues * can_queue. However, for when host_tagset is set,
632 * the total queue depth is can_queue.
efec4b90
BVA
633 */
634 unsigned nr_hw_queues;
af183095 635 unsigned nr_maps;
5dc2b89e 636 unsigned active_mode:2;
1da177e4
LT
637
638 /*
639 * Host has requested that no further requests come through for the
640 * time being.
641 */
642 unsigned host_self_blocked:1;
643
644 /*
645 * Host uses correct SCSI ordering not PC ordering. The bit is
646 * set for the minority of drivers whose authors actually read
d850bd34 647 * the spec ;).
1da177e4
LT
648 */
649 unsigned reverse_ordering:1;
650
d850bd34 651 /* Task mgmt function in progress */
d7a1bb0a
JS
652 unsigned tmf_in_progress:1;
653
3e082a91
MW
654 /* Asynchronous scan in progress */
655 unsigned async_scan:1;
656
ae0751ff
LM
657 /* Don't resume host in EH */
658 unsigned eh_noresume:1;
659
54b2b50c
MP
660 /* The controller does not support WRITE SAME */
661 unsigned no_write_same:1;
662
bdb01301
HR
663 /* True if the host uses host-wide tagspace */
664 unsigned host_tagset:1;
665
b125bb99
BVA
666 /* The queuecommand callback may block. See also BLK_MQ_F_BLOCKING. */
667 unsigned queuecommand_may_block:1;
668
a35bb445
VK
669 /* Host responded with short (<36 bytes) INQUIRY result */
670 unsigned short_inquiry:1;
671
93ab8c8f
HR
672 /* The transport requires the LUN bits NOT to be stored in CDB[1] */
673 unsigned no_scsi2_lun_in_cdb:1;
674
6248d7f7
CH
675 unsigned no_highmem:1;
676
1da177e4
LT
677 /*
678 * Optional work queue to be utilized by the transport
679 */
aab0de24 680 char work_q_name[20];
1da177e4
LT
681 struct workqueue_struct *work_q;
682
e494f6a7
HR
683 /*
684 * Task management function work queue
685 */
686 struct workqueue_struct *tmf_work_q;
687
1da177e4
LT
688 /*
689 * Value host_blocked counts down from
690 */
691 unsigned int max_host_blocked;
692
4469f987
MP
693 /* Protection Information */
694 unsigned int prot_capabilities;
695 unsigned char prot_guard_type;
696
1da177e4
LT
697 /* legacy crap */
698 unsigned long base;
699 unsigned long io_port;
700 unsigned char n_io_port;
701 unsigned char dma_channel;
702 unsigned int irq;
703
704
d3301874 705 enum scsi_host_state shost_state;
1da177e4
LT
706
707 /* ldm bits */
ee959b00 708 struct device shost_gendev, shost_dev;
1da177e4 709
1da177e4
LT
710 /*
711 * Points to the transport data (if any) which is allocated
712 * separately
713 */
714 void *shost_data;
715
d139b9bd
JB
716 /*
717 * Points to the physical bus device we'd use to do DMA
718 * Needed just in case we have virtual hosts.
719 */
720 struct device *dma_dev;
721
4380e64a
PW
722 /* Delay for runtime autosuspend */
723 int rpm_autosuspend_delay;
724
1da177e4
LT
725 /*
726 * We should ensure that this is aligned, both for better performance
727 * and also because some compilers (m68k) don't automatically force
728 * alignment to a long boundary.
729 */
5febf6d6 730 unsigned long hostdata[] /* Used for storage of host specific stuff */
1da177e4
LT
731 __attribute__ ((aligned (sizeof(unsigned long))));
732};
733
734#define class_to_shost(d) \
ee959b00 735 container_of(d, struct Scsi_Host, shost_dev)
1da177e4 736
9ccfc756
JB
737#define shost_printk(prefix, shost, fmt, a...) \
738 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
739
bcd92c9f
CH
740static inline void *shost_priv(struct Scsi_Host *shost)
741{
742 return (void *)shost->hostdata;
743}
9ccfc756 744
1da177e4
LT
745int scsi_is_host_device(const struct device *);
746
747static inline struct Scsi_Host *dev_to_shost(struct device *dev)
748{
749 while (!scsi_is_host_device(dev)) {
750 if (!dev->parent)
751 return NULL;
752 dev = dev->parent;
753 }
754 return container_of(dev, struct Scsi_Host, shost_gendev);
755}
756
939647ee
JB
757static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
758{
759 return shost->shost_state == SHOST_RECOVERY ||
760 shost->shost_state == SHOST_CANCEL_RECOVERY ||
d7a1bb0a
JS
761 shost->shost_state == SHOST_DEL_RECOVERY ||
762 shost->tmf_in_progress;
939647ee
JB
763}
764
1da177e4
LT
765extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
766extern void scsi_flush_work(struct Scsi_Host *);
767
e0d3f2c6 768extern struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *, int);
d139b9bd
JB
769extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
770 struct device *,
771 struct device *);
77916da7
BVA
772#if defined(CONFIG_SCSI_PROC_FS)
773struct proc_dir_entry *
774scsi_template_proc_dir(const struct scsi_host_template *sht);
775#else
776#define scsi_template_proc_dir(sht) NULL
777#endif
1da177e4 778extern void scsi_scan_host(struct Scsi_Host *);
ff48b378 779extern int scsi_rescan_device(struct scsi_device *sdev);
1da177e4
LT
780extern void scsi_remove_host(struct Scsi_Host *);
781extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
c84b023a 782extern int scsi_host_busy(struct Scsi_Host *shost);
1da177e4 783extern void scsi_host_put(struct Scsi_Host *t);
62ec2092 784extern struct Scsi_Host *scsi_host_lookup(unsigned int hostnum);
d3301874 785extern const char *scsi_host_state_name(enum scsi_host_state);
466552b9 786extern void scsi_host_complete_all_commands(struct Scsi_Host *shost,
62af0ee9 787 enum scsi_host_status status);
1da177e4 788
d139b9bd
JB
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
1da177e4
LT
795static inline struct device *scsi_get_device(struct Scsi_Host *shost)
796{
797 return shost->shost_gendev.parent;
798}
799
82f29467
MA
800/**
801 * scsi_host_scan_allowed - Is scanning of this host allowed
802 * @shost: Pointer to Scsi_Host.
803 **/
804static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
805{
76e4e12f
MC
806 return shost->shost_state == SHOST_RUNNING ||
807 shost->shost_state == SHOST_RECOVERY;
82f29467
MA
808}
809
1da177e4
LT
810extern void scsi_unblock_requests(struct Scsi_Host *);
811extern void scsi_block_requests(struct Scsi_Host *);
2bb95584
HR
812extern int scsi_host_block(struct Scsi_Host *shost);
813extern int scsi_host_unblock(struct Scsi_Host *shost, int new_state);
1da177e4 814
dcece99e 815void scsi_host_busy_iter(struct Scsi_Host *,
2dd6532e 816 bool (*fn)(struct scsi_cmnd *, void *), void *priv);
dcece99e 817
1da177e4 818struct class_container;
b58d9154 819
4469f987
MP
820/*
821 * DIF defines the exchange of protection information between
822 * initiator and SBC block device.
823 *
824 * DIX defines the exchange of protection information between OS and
825 * 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 must
840 * indicate their capabilities by setting the prot_capabilities using
841 * 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
13f05c8d
MP
853static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
854{
855 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
856}
857
4469f987
MP
858static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
859{
b2b465e9
MP
860 static unsigned char cap[] = { 0,
861 SHOST_DIF_TYPE1_PROTECTION,
862 SHOST_DIF_TYPE2_PROTECTION,
863 SHOST_DIF_TYPE3_PROTECTION };
4469f987 864
4d24834d 865 if (target_type >= ARRAY_SIZE(cap))
fe542396
MP
866 return 0;
867
b2b465e9 868 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
4469f987
MP
869}
870
871static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
872{
35e1a5d9 873#if defined(CONFIG_BLK_DEV_INTEGRITY)
b2b465e9
MP
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
4d24834d 879 if (target_type >= ARRAY_SIZE(cap))
fe542396
MP
880 return 0;
881
b2b465e9 882 return shost->prot_capabilities & cap[target_type];
35e1a5d9 883#endif
4469f987
MP
884 return 0;
885}
886
887/*
888 * All DIX-capable initiators must support the T10-mandated CRC
889 * checksum. Controllers can optionally implement the IP checksum
890 * scheme which has much lower impact on system performance. Note
891 * that the main rationale for the checksum is to match integrity
892 * metadata with data. Detecting bit errors are a job for ECC memory
893 * 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
47ba39ee 911extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
1da177e4
LT
912
913#endif /* _SCSI_SCSI_HOST_H */