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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#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>
Arjan van de Ven0b950672006-01-11 13:16:10 +01008#include <linux/mutex.h>
Al Viro0ffddfb2013-03-30 23:58:05 -04009#include <linux/seq_file.h>
Christoph Hellwigd2852032014-01-17 12:06:53 +010010#include <linux/blk-mq.h>
James Bottomley4660c8e2008-02-10 09:42:46 -060011#include <scsi/scsi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012
FUJITA Tomonorib58d9152006-11-16 19:24:10 +090013struct request_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070014struct block_device;
Christoph Hellwig7dfdc9a2005-10-31 18:49:52 +010015struct completion;
Linus Torvalds1da177e2005-04-16 15:20:36 -070016struct module;
17struct scsi_cmnd;
18struct scsi_device;
Christoph Hellwig89d9a562014-02-20 14:21:01 -080019struct scsi_host_cmd_pool;
James Bottomleya283bd32005-05-24 12:06:38 -050020struct scsi_target;
Linus Torvalds1da177e2005-04-16 15:20:36 -070021struct Scsi_Host;
22struct scsi_host_cmd_pool;
23struct scsi_transport_template;
James Bottomley86e33a22006-08-30 09:45:51 -040024struct blk_queue_tags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
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
James Bottomley4660c8e2008-02-10 09:42:46 -060032 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070036 * Anything else: Indicates the maximum number of chains that can be
37 * used in one scatter-gather request.
38 */
39#define SG_NONE 0
James Bottomley4660c8e2008-02-10 09:42:46 -060040#define SG_ALL SCSI_MAX_SG_SEGMENTS
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
FUJITA Tomonori5dc2b892007-09-01 02:02:20 +090042#define MODE_UNKNOWN 0x00
43#define MODE_INITIATOR 0x01
44#define MODE_TARGET 0x02
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46#define DISABLE_CLUSTERING 0
47#define ENABLE_CLUSTERING 1
48
Mike Christiee881a172009-10-15 17:46:39 -070049enum {
50 SCSI_QDEPTH_DEFAULT, /* default requested change, e.g. from sysfs */
51 SCSI_QDEPTH_QFULL, /* scsi-ml requested due to queue full */
Lucas De Marchi25985ed2011-03-30 22:57:33 -030052 SCSI_QDEPTH_RAMP_UP, /* scsi-ml requested due to threshold event */
Mike Christiee881a172009-10-15 17:46:39 -070053};
54
Linus Torvalds1da177e2005-04-16 15:20:36 -070055struct scsi_host_template {
56 struct module *module;
57 const char *name;
58
59 /*
60 * Used to initialize old-style drivers. For new-style drivers
61 * just perform all work in your module initialization function.
62 *
63 * Status: OBSOLETE
64 */
65 int (* detect)(struct scsi_host_template *);
66
67 /*
68 * Used as unload callback for hosts with old-style drivers.
69 *
70 * Status: OBSOLETE
71 */
72 int (* release)(struct Scsi_Host *);
73
74 /*
75 * The info function will return whatever useful information the
76 * developer sees fit. If not provided, then the name field will
77 * be used instead.
78 *
79 * Status: OPTIONAL
80 */
81 const char *(* info)(struct Scsi_Host *);
82
83 /*
84 * Ioctl interface
85 *
86 * Status: OPTIONAL
87 */
88 int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
89
90
91#ifdef CONFIG_COMPAT
92 /*
93 * Compat handler. Handle 32bit ABI.
94 * When unknown ioctl is passed return -ENOIOCTLCMD.
95 *
96 * Status: OPTIONAL
97 */
98 int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
99#endif
100
101 /*
102 * The queuecommand function is used to queue up a scsi
103 * command block to the LLDD. When the driver finished
104 * processing the command the done callback is invoked.
105 *
106 * If queuecommand returns 0, then the HBA has accepted the
107 * command. The done() function must be called on the command
108 * when the driver has finished with it. (you may call done on the
109 * command before queuecommand returns, but in this case you
110 * *must* return 0 from queuecommand).
111 *
112 * Queuecommand may also reject the command, in which case it may
113 * not touch the command and must not call done() for it.
114 *
115 * There are two possible rejection returns:
116 *
117 * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
118 * allow commands to other devices serviced by this host.
119 *
120 * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
121 * host temporarily.
122 *
123 * For compatibility, any other non-zero return is treated the
124 * same as SCSI_MLQUEUE_HOST_BUSY.
125 *
126 * NOTE: "temporarily" means either until the next command for#
127 * this device/host completes, or a period of time determined by
128 * I/O pressure in the system if there are no other outstanding
129 * commands.
130 *
131 * STATUS: REQUIRED
132 */
Jeff Garzikf2812332010-11-16 02:10:29 -0500133 int (* queuecommand)(struct Scsi_Host *, struct scsi_cmnd *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
135 /*
136 * This is an error handling strategy routine. You don't need to
137 * define one of these if you don't want to - there is a default
138 * routine that is present that should work in most cases. For those
139 * driver authors that have the inclination and ability to write their
140 * own strategy routine, this is where it is specified. Note - the
141 * strategy routine is *ALWAYS* run in the context of the kernel eh
142 * thread. Thus you are guaranteed to *NOT* be in an interrupt
143 * handler when you execute this, and you are also guaranteed to
144 * *NOT* have any other commands being queued while you are in the
145 * strategy routine. When you return from this function, operations
146 * return to normal.
147 *
148 * See scsi_error.c scsi_unjam_host for additional comments about
149 * what this function should and should not be attempting to do.
150 *
151 * Status: REQUIRED (at least one of them)
152 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 int (* eh_abort_handler)(struct scsi_cmnd *);
154 int (* eh_device_reset_handler)(struct scsi_cmnd *);
Mike Christie30bd7df2008-02-29 18:25:19 -0600155 int (* eh_target_reset_handler)(struct scsi_cmnd *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 int (* eh_bus_reset_handler)(struct scsi_cmnd *);
157 int (* eh_host_reset_handler)(struct scsi_cmnd *);
158
159 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 * Before the mid layer attempts to scan for a new device where none
161 * currently exists, it will call this entry in your driver. Should
162 * your driver need to allocate any structs or perform any other init
163 * items in order to send commands to a currently unused target/lun
164 * combo, then this is where you can perform those allocations. This
165 * is specifically so that drivers won't have to perform any kind of
166 * "is this a new device" checks in their queuecommand routine,
167 * thereby making the hot path a bit quicker.
168 *
169 * Return values: 0 on success, non-0 on failure
170 *
171 * Deallocation: If we didn't find any devices at this ID, you will
172 * get an immediate call to slave_destroy(). If we find something
173 * here then you will get a call to slave_configure(), then the
174 * device will be used for however long it is kept around, then when
175 * the device is removed from the system (or * possibly at reboot
176 * time), you will then get a call to slave_destroy(). This is
177 * assuming you implement slave_configure and slave_destroy.
178 * However, if you allocate memory and hang it off the device struct,
179 * then you must implement the slave_destroy() routine at a minimum
180 * in order to avoid leaking memory
181 * each time a device is tore down.
182 *
183 * Status: OPTIONAL
184 */
185 int (* slave_alloc)(struct scsi_device *);
186
187 /*
188 * Once the device has responded to an INQUIRY and we know the
189 * device is online, we call into the low level driver with the
190 * struct scsi_device *. If the low level device driver implements
191 * this function, it *must* perform the task of setting the queue
192 * depth on the device. All other tasks are optional and depend
193 * on what the driver supports and various implementation details.
194 *
195 * Things currently recommended to be handled at this time include:
196 *
197 * 1. Setting the device queue depth. Proper setting of this is
198 * described in the comments for scsi_adjust_queue_depth.
199 * 2. Determining if the device supports the various synchronous
200 * negotiation protocols. The device struct will already have
201 * responded to INQUIRY and the results of the standard items
202 * will have been shoved into the various device flag bits, eg.
203 * device->sdtr will be true if the device supports SDTR messages.
204 * 3. Allocating command structs that the device will need.
205 * 4. Setting the default timeout on this device (if needed).
206 * 5. Anything else the low level driver might want to do on a device
207 * specific setup basis...
208 * 6. Return 0 on success, non-0 on error. The device will be marked
209 * as offline on error so that no access will occur. If you return
210 * non-0, your slave_destroy routine will never get called for this
211 * device, so don't leave any loose memory hanging around, clean
212 * up after yourself before returning non-0
213 *
214 * Status: OPTIONAL
215 */
216 int (* slave_configure)(struct scsi_device *);
217
218 /*
219 * Immediately prior to deallocating the device and after all activity
220 * has ceased the mid layer calls this point so that the low level
221 * driver may completely detach itself from the scsi device and vice
222 * versa. The low level driver is responsible for freeing any memory
223 * it allocated in the slave_alloc or slave_configure calls.
224 *
225 * Status: OPTIONAL
226 */
227 void (* slave_destroy)(struct scsi_device *);
228
229 /*
James Bottomleya283bd32005-05-24 12:06:38 -0500230 * Before the mid layer attempts to scan for a new device attached
231 * to a target where no target currently exists, it will call this
232 * entry in your driver. Should your driver need to allocate any
233 * structs or perform any other init items in order to send commands
234 * to a currently unused target, then this is where you can perform
235 * those allocations.
236 *
237 * Return values: 0 on success, non-0 on failure
238 *
239 * Status: OPTIONAL
240 */
241 int (* target_alloc)(struct scsi_target *);
242
243 /*
244 * Immediately prior to deallocating the target structure, and
245 * after all activity to attached scsi devices has ceased, the
246 * midlayer calls this point so that the driver may deallocate
247 * and terminate any references to the target.
248 *
249 * Status: OPTIONAL
250 */
251 void (* target_destroy)(struct scsi_target *);
252
253 /*
Matthew Wilcox1aa8fab2006-11-22 13:24:54 -0700254 * If a host has the ability to discover targets on its own instead
255 * of scanning the entire bus, it can fill in this function and
256 * call scsi_scan_host(). This function will be called periodically
257 * until it returns 1 with the scsi_host and the elapsed time of
258 * the scan in jiffies.
259 *
260 * Status: OPTIONAL
261 */
262 int (* scan_finished)(struct Scsi_Host *, unsigned long);
263
264 /*
265 * If the host wants to be called before the scan starts, but
266 * after the midlayer has set up ready for the scan, it can fill
267 * in this function.
Pavel Machekd850bd32008-02-04 23:53:24 -0800268 *
269 * Status: OPTIONAL
Matthew Wilcox1aa8fab2006-11-22 13:24:54 -0700270 */
271 void (* scan_start)(struct Scsi_Host *);
272
273 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800274 * Fill in this function to allow the queue depth of this host
275 * to be changeable (on a per device basis). Returns either
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 * the current queue depth setting (may be different from what
277 * was passed in) or an error. An error should only be
278 * returned if the requested depth is legal but the driver was
279 * unable to set it. If the requested depth is illegal, the
280 * driver should set and return the closest legal queue depth.
281 *
Pavel Machekd850bd32008-02-04 23:53:24 -0800282 * Status: OPTIONAL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 */
Mike Christiee881a172009-10-15 17:46:39 -0700284 int (* change_queue_depth)(struct scsi_device *, int, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285
286 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800287 * Fill in this function to allow the changing of tag types
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 * (this also allows the enabling/disabling of tag command
289 * queueing). An error should only be returned if something
290 * went wrong in the driver while trying to set the tag type.
291 * If the driver doesn't support the requested tag type, then
292 * it should set the closest type it does support without
293 * returning an error. Returns the actual tag type set.
Pavel Machekd850bd32008-02-04 23:53:24 -0800294 *
295 * Status: OPTIONAL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 */
297 int (* change_queue_type)(struct scsi_device *, int);
298
299 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800300 * This function determines the BIOS parameters for a given
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 * harddisk. These tend to be numbers that are made up by
302 * the host adapter. Parameters:
303 * size, device, list (heads, sectors, cylinders)
304 *
Pavel Machekd850bd32008-02-04 23:53:24 -0800305 * Status: OPTIONAL
306 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 int (* bios_param)(struct scsi_device *, struct block_device *,
308 sector_t, int []);
309
310 /*
Tejun Heo72ec24b2010-05-15 20:09:32 +0200311 * This function is called when one or more partitions on the
312 * device reach beyond the end of the device.
313 *
314 * Status: OPTIONAL
315 */
316 void (*unlock_native_capacity)(struct scsi_device *);
317
318 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 * Can be used to export driver statistics and other infos to the
320 * world outside the kernel ie. userspace and it also provides an
321 * interface to feed the driver with information.
322 *
323 * Status: OBSOLETE
324 */
Al Viro0ffddfb2013-03-30 23:58:05 -0400325 int (*show_info)(struct seq_file *, struct Scsi_Host *);
326 int (*write_info)(struct Scsi_Host *, char *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327
328 /*
James Bottomley6c5f8ce2007-03-16 17:44:41 -0500329 * This is an optional routine that allows the transport to become
330 * involved when a scsi io timer fires. The return value tells the
331 * timer routine how to finish the io timeout handling:
332 * EH_HANDLED: I fixed the error, please complete the command
333 * EH_RESET_TIMER: I need more time, reset the timer and
334 * begin counting again
335 * EH_NOT_HANDLED Begin normal error recovery
336 *
337 * Status: OPTIONAL
338 */
Jens Axboe242f9dc2008-09-14 05:55:09 -0700339 enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
James Bottomley6c5f8ce2007-03-16 17:44:41 -0500340
Vikas Chaudhary29443692011-08-12 02:51:28 -0700341 /* This is an optional routine that allows transport to initiate
342 * LLD adapter or firmware reset using sysfs attribute.
343 *
344 * Return values: 0 on success, -ve value on failure.
345 *
346 * Status: OPTIONAL
347 */
348
349 int (*host_reset)(struct Scsi_Host *shost, int reset_type);
350#define SCSI_ADAPTER_RESET 1
351#define SCSI_FIRMWARE_RESET 2
352
353
James Bottomley6c5f8ce2007-03-16 17:44:41 -0500354 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 * Name of proc directory
356 */
Kristian Høgsbergb02b6bc2007-05-09 19:23:12 -0400357 const char *proc_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
359 /*
360 * Used to store the procfs directory if a driver implements the
Al Viro70ef4572013-03-31 13:27:56 -0400361 * show_info method.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 */
363 struct proc_dir_entry *proc_dir;
364
365 /*
366 * This determines if we will use a non-interrupt driven
Pavel Machekd850bd32008-02-04 23:53:24 -0800367 * or an interrupt driven scheme. It is set to the maximum number
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 * of simultaneous commands a given host adapter will accept.
369 */
370 int can_queue;
371
372 /*
373 * In many instances, especially where disconnect / reconnect are
374 * supported, our host also has an ID on the SCSI bus. If this is
375 * the case, then it must be reserved. Please set this_id to -1 if
376 * your setup is in single initiator mode, and the host lacks an
377 * ID.
378 */
379 int this_id;
380
381 /*
382 * This determines the degree to which the host adapter is capable
383 * of scatter-gather.
384 */
385 unsigned short sg_tablesize;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200386 unsigned short sg_prot_tablesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
388 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800389 * Set this if the host adapter has limitations beside segment count.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390 */
Akinobu Mita8ed5a4d2014-06-02 22:56:48 +0900391 unsigned int max_sectors;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392
393 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800394 * DMA scatter gather segment boundary limit. A segment crossing this
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 * boundary will be split in two.
396 */
397 unsigned long dma_boundary;
398
399 /*
400 * This specifies "machine infinity" for host templates which don't
401 * limit the transfer size. Note this limit represents an absolute
402 * maximum, and may be over the transfer limits allowed for
Pavel Machekd850bd32008-02-04 23:53:24 -0800403 * individual devices (e.g. 256 for SCSI-1).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 */
405#define SCSI_DEFAULT_MAX_SECTORS 1024
406
407 /*
408 * True if this host adapter can make good use of linked commands.
409 * This will allow more than one command to be queued to a given
410 * unit on a given host. Set this to the maximum number of command
411 * blocks to be provided for each device. Set this to 1 for one
412 * command block per lun, 2 for two, etc. Do not set this to 0.
413 * You should make sure that the host adapter will do the right thing
414 * before you try setting this above 1.
415 */
416 short cmd_per_lun;
417
418 /*
419 * present contains counter indicating how many boards of this
420 * type were found when we did the scan.
421 */
422 unsigned char present;
423
424 /*
FUJITA Tomonori5dc2b892007-09-01 02:02:20 +0900425 * This specifies the mode that a LLD supports.
426 */
427 unsigned supported_mode:2;
428
429 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800430 * True if this host adapter uses unchecked DMA onto an ISA bus.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 */
432 unsigned unchecked_isa_dma:1;
433
434 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800435 * True if this host adapter can make good use of clustering.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 * I originally thought that if the tablesize was large that it
437 * was a waste of CPU cycles to prepare a cluster list, but
438 * it works out that the Buslogic is faster if you use a smaller
439 * number of segments (i.e. use clustering). I guess it is
440 * inefficient.
441 */
442 unsigned use_clustering:1;
443
444 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800445 * True for emulated SCSI host adapters (e.g. ATAPI).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 */
447 unsigned emulated:1;
448
449 /*
450 * True if the low-level driver performs its own reset-settle delays.
451 */
452 unsigned skip_settle_delay:1;
453
454 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800455 * True if we are using ordered write support.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 unsigned ordered_tag:1;
458
Martin K. Petersen54b2b502013-10-23 06:25:40 -0400459 /* True if the controller does not support WRITE SAME */
460 unsigned no_write_same:1;
461
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 /*
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100463 * True if asynchronous aborts are not supported
464 */
465 unsigned no_async_abort:1;
466
467 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800468 * Countdown for host blocking with no commands outstanding.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 */
470 unsigned int max_host_blocked;
471
472 /*
473 * Default value for the blocking. If the queue is empty,
474 * host_blocked counts down in the request_fn until it restarts
475 * host operations as zero is reached.
476 *
477 * FIXME: This should probably be a value in the template
478 */
479#define SCSI_DEFAULT_HOST_BLOCKED 7
480
481 /*
482 * Pointer to the sysfs class properties for this host, NULL terminated.
483 */
Tony Jonesee959b02008-02-22 00:13:36 +0100484 struct device_attribute **shost_attrs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
486 /*
487 * Pointer to the SCSI device properties for this host, NULL terminated.
488 */
489 struct device_attribute **sdev_attrs;
490
491 /*
492 * List of hosts per template.
493 *
494 * This is only for use by scsi_module.c for legacy templates.
495 * For these access to it is synchronized implicitly by
496 * module_init/module_exit.
497 */
498 struct list_head legacy_hosts;
James Smart9e4f5e22009-03-26 13:33:19 -0400499
500 /*
501 * Vendor Identifier associated with the host
502 *
503 * Note: When specifying vendor_id, be sure to read the
504 * Vendor Type and ID formatting requirements specified in
505 * scsi_netlink.h
506 */
507 u64 vendor_id;
Christoph Hellwig89d9a562014-02-20 14:21:01 -0800508
509 /*
510 * Additional per-command data allocated for the driver.
511 */
512 unsigned int cmd_size;
513 struct scsi_host_cmd_pool *cmd_pool;
Christoph Hellwigd2852032014-01-17 12:06:53 +0100514
515 /* temporary flag to disable blk-mq I/O path */
516 bool disable_blk_mq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517};
518
519/*
Jeff Garzikf2812332010-11-16 02:10:29 -0500520 * Temporary #define for host lock push down. Can be removed when all
521 * drivers have been updated to take advantage of unlocked
522 * queuecommand.
523 *
524 */
525#define DEF_SCSI_QCMD(func_name) \
526 int func_name(struct Scsi_Host *shost, struct scsi_cmnd *cmd) \
527 { \
528 unsigned long irq_flags; \
529 int rc; \
530 spin_lock_irqsave(shost->host_lock, irq_flags); \
531 scsi_cmd_get_serial(shost, cmd); \
532 rc = func_name##_lck (cmd, cmd->scsi_done); \
533 spin_unlock_irqrestore(shost->host_lock, irq_flags); \
534 return rc; \
535 }
536
537
538/*
Mike Andersond3301872005-06-16 11:12:38 -0700539 * shost state: If you alter this, you also need to alter scsi_sysfs.c
540 * (for the ascii descriptions) and the state model enforcer:
541 * scsi_host_set_state()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 */
Mike Andersond3301872005-06-16 11:12:38 -0700543enum scsi_host_state {
544 SHOST_CREATED = 1,
545 SHOST_RUNNING,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 SHOST_CANCEL,
Mike Andersond3301872005-06-16 11:12:38 -0700547 SHOST_DEL,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 SHOST_RECOVERY,
James Bottomley939647e2005-09-18 15:05:20 -0500549 SHOST_CANCEL_RECOVERY,
550 SHOST_DEL_RECOVERY,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551};
552
553struct Scsi_Host {
554 /*
555 * __devices is protected by the host_lock, but you should
556 * usually use scsi_device_lookup / shost_for_each_device
557 * to access it and don't care about locking yourself.
558 * In the rare case of beeing in irq context you can use
559 * their __ prefixed variants with the lock held. NEVER
560 * access this list directly from a driver.
561 */
562 struct list_head __devices;
563 struct list_head __targets;
564
565 struct scsi_host_cmd_pool *cmd_pool;
566 spinlock_t free_list_lock;
567 struct list_head free_list; /* backup store of cmd structs */
568 struct list_head starved_list;
569
570 spinlock_t default_lock;
571 spinlock_t *host_lock;
572
Arjan van de Ven0b950672006-01-11 13:16:10 +0100573 struct mutex scan_mutex;/* serialize scanning activity */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574
575 struct list_head eh_cmd_q;
576 struct task_struct * ehandler; /* Error recovery thread. */
Christoph Hellwig7dfdc9a2005-10-31 18:49:52 +0100577 struct completion * eh_action; /* Wait for specific actions on the
578 host. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 wait_queue_head_t host_wait;
580 struct scsi_host_template *hostt;
581 struct scsi_transport_template *transportt;
06f81ea2005-04-17 14:57:29 -0500582
583 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800584 * Area to keep a shared tag map (if needed, will be
585 * NULL if not).
James Bottomley86e33a22006-08-30 09:45:51 -0400586 */
Christoph Hellwigd2852032014-01-17 12:06:53 +0100587 union {
588 struct blk_queue_tag *bqt;
589 struct blk_mq_tag_set tag_set;
590 };
James Bottomley86e33a22006-08-30 09:45:51 -0400591
Christoph Hellwig74665012014-01-22 15:29:29 +0100592 atomic_t host_busy; /* commands actually active on low-level */
Christoph Hellwigcd9070c2014-01-23 12:07:41 +0100593 atomic_t host_blocked;
594
Christoph Hellwig74665012014-01-22 15:29:29 +0100595 unsigned int host_failed; /* commands that failed.
596 protected by host_lock */
Tejun Heoee7863b2006-05-15 20:57:20 +0900597 unsigned int host_eh_scheduled; /* EH scheduled without command */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598
Matthew Wilcox6d49f632008-07-15 14:54:16 -0600599 unsigned int host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600
Hannes Reineckeb4562022013-10-23 10:51:21 +0200601 /* next two fields are used to bound the time spent in error handling */
602 int eh_deadline;
603 unsigned long last_reset;
604
605
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 /*
607 * These three parameters can be used to allow for wide scsi,
608 * and for host adapters that support multiple busses
609 * The first two should be set to 1 more than the actual max id
Hannes Reinecke1abf6352014-06-25 15:27:38 +0200610 * or lun (e.g. 8 for SCSI parallel systems).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 unsigned int max_channel;
Hannes Reinecke1abf6352014-06-25 15:27:38 +0200613 unsigned int max_id;
614 u64 max_lun;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
616 /*
617 * This is a unique identifier that must be assigned so that we
618 * have some way of identifying each detected host adapter properly
619 * and uniquely. For hosts that do not support more than one card
620 * in the system at one time, this does not need to be set. It is
621 * initialized to 0 in scsi_register.
622 */
623 unsigned int unique_id;
624
625 /*
626 * The maximum length of SCSI commands that this host can accept.
627 * Probably 12 for most host adapters, but could be 16 for others.
Boaz Harroshdb4742d2008-04-30 11:27:26 +0300628 * or 260 if the driver supports variable length cdbs.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629 * For drivers that don't set this field, a value of 12 is
Boaz Harroshdb4742d2008-04-30 11:27:26 +0300630 * assumed.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 */
Boaz Harroshdb4742d2008-04-30 11:27:26 +0300632 unsigned short max_cmd_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633
634 int this_id;
635 int can_queue;
636 short cmd_per_lun;
637 short unsigned int sg_tablesize;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200638 short unsigned int sg_prot_tablesize;
Akinobu Mita8ed5a4d2014-06-02 22:56:48 +0900639 unsigned int max_sectors;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 unsigned long dma_boundary;
641 /*
642 * Used to assign serial numbers to the cmds.
643 * Protected by the host lock.
644 */
Matthew Wilcox12a44162007-09-18 19:54:43 -0600645 unsigned long cmd_serial_number;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646
FUJITA Tomonori5dc2b892007-09-01 02:02:20 +0900647 unsigned active_mode:2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 unsigned unchecked_isa_dma:1;
649 unsigned use_clustering:1;
650 unsigned use_blk_tcq:1;
651
652 /*
653 * Host has requested that no further requests come through for the
654 * time being.
655 */
656 unsigned host_self_blocked:1;
657
658 /*
659 * Host uses correct SCSI ordering not PC ordering. The bit is
660 * set for the minority of drivers whose authors actually read
Pavel Machekd850bd32008-02-04 23:53:24 -0800661 * the spec ;).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 */
663 unsigned reverse_ordering:1;
664
665 /*
Pavel Machekd850bd32008-02-04 23:53:24 -0800666 * Ordered write support
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 unsigned ordered_tag:1;
669
Pavel Machekd850bd32008-02-04 23:53:24 -0800670 /* Task mgmt function in progress */
James Smartd7a1bb02006-03-08 14:50:12 -0500671 unsigned tmf_in_progress:1;
672
Matthew Wilcox3e082a92006-09-28 15:19:20 -0600673 /* Asynchronous scan in progress */
674 unsigned async_scan:1;
675
Lin Mingae0751f2011-12-05 09:20:24 +0800676 /* Don't resume host in EH */
677 unsigned eh_noresume:1;
678
Martin K. Petersen54b2b502013-10-23 06:25:40 -0400679 /* The controller does not support WRITE SAME */
680 unsigned no_write_same:1;
681
Christoph Hellwigd2852032014-01-17 12:06:53 +0100682 unsigned use_blk_mq:1;
683
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 /*
685 * Optional work queue to be utilized by the transport
686 */
Kay Sieversaab0de22008-05-02 06:02:41 +0200687 char work_q_name[20];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 struct workqueue_struct *work_q;
689
690 /*
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100691 * Task management function work queue
692 */
693 struct workqueue_struct *tmf_work_q;
694
695 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 * Value host_blocked counts down from
697 */
698 unsigned int max_host_blocked;
699
Martin K. Petersen4469f982008-07-17 04:28:30 -0400700 /* Protection Information */
701 unsigned int prot_capabilities;
702 unsigned char prot_guard_type;
703
FUJITA Tomonorib58d9152006-11-16 19:24:10 +0900704 /*
705 * q used for scsi_tgt msgs, async events or any other requests that
706 * need to be processed in userspace
707 */
708 struct request_queue *uspace_req_q;
709
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 /* legacy crap */
711 unsigned long base;
712 unsigned long io_port;
713 unsigned char n_io_port;
714 unsigned char dma_channel;
715 unsigned int irq;
716
717
Mike Andersond3301872005-06-16 11:12:38 -0700718 enum scsi_host_state shost_state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719
720 /* ldm bits */
Tony Jonesee959b02008-02-22 00:13:36 +0100721 struct device shost_gendev, shost_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
723 /*
724 * List of hosts per template.
725 *
726 * This is only for use by scsi_module.c for legacy templates.
727 * For these access to it is synchronized implicitly by
728 * module_init/module_exit.
729 */
730 struct list_head sht_legacy_list;
731
732 /*
733 * Points to the transport data (if any) which is allocated
734 * separately
735 */
736 void *shost_data;
737
738 /*
James Bottomleyd139b9b2009-11-05 13:33:12 -0600739 * Points to the physical bus device we'd use to do DMA
740 * Needed just in case we have virtual hosts.
741 */
742 struct device *dma_dev;
743
744 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 * We should ensure that this is aligned, both for better performance
746 * and also because some compilers (m68k) don't automatically force
747 * alignment to a long boundary.
748 */
749 unsigned long hostdata[0] /* Used for storage of host specific stuff */
750 __attribute__ ((aligned (sizeof(unsigned long))));
751};
752
753#define class_to_shost(d) \
Tony Jonesee959b02008-02-22 00:13:36 +0100754 container_of(d, struct Scsi_Host, shost_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755
James Bottomley9ccfc752005-10-02 11:45:08 -0500756#define shost_printk(prefix, shost, fmt, a...) \
757 dev_printk(prefix, &(shost)->shost_gendev, fmt, ##a)
758
Christoph Hellwigbcd92c92007-05-31 20:12:26 +0200759static inline void *shost_priv(struct Scsi_Host *shost)
760{
761 return (void *)shost->hostdata;
762}
James Bottomley9ccfc752005-10-02 11:45:08 -0500763
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764int scsi_is_host_device(const struct device *);
765
766static inline struct Scsi_Host *dev_to_shost(struct device *dev)
767{
768 while (!scsi_is_host_device(dev)) {
769 if (!dev->parent)
770 return NULL;
771 dev = dev->parent;
772 }
773 return container_of(dev, struct Scsi_Host, shost_gendev);
774}
775
James Bottomley939647e2005-09-18 15:05:20 -0500776static inline int scsi_host_in_recovery(struct Scsi_Host *shost)
777{
778 return shost->shost_state == SHOST_RECOVERY ||
779 shost->shost_state == SHOST_CANCEL_RECOVERY ||
James Smartd7a1bb02006-03-08 14:50:12 -0500780 shost->shost_state == SHOST_DEL_RECOVERY ||
781 shost->tmf_in_progress;
James Bottomley939647e2005-09-18 15:05:20 -0500782}
783
Christoph Hellwigd2852032014-01-17 12:06:53 +0100784extern bool scsi_use_blk_mq;
785
786static inline bool shost_use_blk_mq(struct Scsi_Host *shost)
787{
788 return shost->use_blk_mq;
789}
790
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
792extern void scsi_flush_work(struct Scsi_Host *);
793
794extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
James Bottomleyd139b9b2009-11-05 13:33:12 -0600795extern int __must_check scsi_add_host_with_dma(struct Scsi_Host *,
796 struct device *,
797 struct device *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798extern void scsi_scan_host(struct Scsi_Host *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799extern void scsi_rescan_device(struct device *);
800extern void scsi_remove_host(struct Scsi_Host *);
801extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
802extern void scsi_host_put(struct Scsi_Host *t);
803extern struct Scsi_Host *scsi_host_lookup(unsigned short);
Mike Andersond3301872005-06-16 11:12:38 -0700804extern const char *scsi_host_state_name(enum scsi_host_state);
Jeff Garzikf2812332010-11-16 02:10:29 -0500805extern void scsi_cmd_get_serial(struct Scsi_Host *, struct scsi_cmnd *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806
James Bottomleyd139b9b2009-11-05 13:33:12 -0600807static inline int __must_check scsi_add_host(struct Scsi_Host *host,
808 struct device *dev)
809{
810 return scsi_add_host_with_dma(host, dev, dev);
811}
812
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813static inline struct device *scsi_get_device(struct Scsi_Host *shost)
814{
815 return shost->shost_gendev.parent;
816}
817
Mike Anderson82f29462005-06-16 11:14:33 -0700818/**
819 * scsi_host_scan_allowed - Is scanning of this host allowed
820 * @shost: Pointer to Scsi_Host.
821 **/
822static inline int scsi_host_scan_allowed(struct Scsi_Host *shost)
823{
Mike Christie76e4e122011-08-25 00:36:38 -0500824 return shost->shost_state == SHOST_RUNNING ||
825 shost->shost_state == SHOST_RECOVERY;
Mike Anderson82f29462005-06-16 11:14:33 -0700826}
827
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828extern void scsi_unblock_requests(struct Scsi_Host *);
829extern void scsi_block_requests(struct Scsi_Host *);
830
831struct class_container;
FUJITA Tomonorib58d9152006-11-16 19:24:10 +0900832
833extern struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
834 void (*) (struct request_queue *));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835/*
836 * These two functions are used to allocate and free a pseudo device
837 * which will connect to the host adapter itself rather than any
838 * physical device. You must deallocate when you are done with the
839 * thing. This physical pseudo-device isn't real and won't be available
840 * from any high-level drivers.
841 */
842extern void scsi_free_host_dev(struct scsi_device *);
843extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
844
Martin K. Petersen4469f982008-07-17 04:28:30 -0400845/*
846 * DIF defines the exchange of protection information between
847 * initiator and SBC block device.
848 *
849 * DIX defines the exchange of protection information between OS and
850 * initiator.
851 */
852enum scsi_host_prot_capabilities {
853 SHOST_DIF_TYPE1_PROTECTION = 1 << 0, /* T10 DIF Type 1 */
854 SHOST_DIF_TYPE2_PROTECTION = 1 << 1, /* T10 DIF Type 2 */
855 SHOST_DIF_TYPE3_PROTECTION = 1 << 2, /* T10 DIF Type 3 */
856
857 SHOST_DIX_TYPE0_PROTECTION = 1 << 3, /* DIX between OS and HBA only */
858 SHOST_DIX_TYPE1_PROTECTION = 1 << 4, /* DIX with DIF Type 1 */
859 SHOST_DIX_TYPE2_PROTECTION = 1 << 5, /* DIX with DIF Type 2 */
860 SHOST_DIX_TYPE3_PROTECTION = 1 << 6, /* DIX with DIF Type 3 */
861};
862
863/*
864 * SCSI hosts which support the Data Integrity Extensions must
865 * indicate their capabilities by setting the prot_capabilities using
866 * this call.
867 */
868static inline void scsi_host_set_prot(struct Scsi_Host *shost, unsigned int mask)
869{
870 shost->prot_capabilities = mask;
871}
872
873static inline unsigned int scsi_host_get_prot(struct Scsi_Host *shost)
874{
875 return shost->prot_capabilities;
876}
877
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200878static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
879{
880 return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
881}
882
Martin K. Petersen4469f982008-07-17 04:28:30 -0400883static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
884{
Martin K. Petersenb2b465e2009-10-29 22:32:26 -0400885 static unsigned char cap[] = { 0,
886 SHOST_DIF_TYPE1_PROTECTION,
887 SHOST_DIF_TYPE2_PROTECTION,
888 SHOST_DIF_TYPE3_PROTECTION };
Martin K. Petersen4469f982008-07-17 04:28:30 -0400889
Martin K. Petersen4d248342012-09-26 22:39:44 -0400890 if (target_type >= ARRAY_SIZE(cap))
Martin K. Petersenfe542392012-09-21 12:44:12 -0400891 return 0;
892
Martin K. Petersenb2b465e2009-10-29 22:32:26 -0400893 return shost->prot_capabilities & cap[target_type] ? target_type : 0;
Martin K. Petersen4469f982008-07-17 04:28:30 -0400894}
895
896static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsigned int target_type)
897{
Martin K. Petersen35e1a5d2009-09-18 17:33:00 -0400898#if defined(CONFIG_BLK_DEV_INTEGRITY)
Martin K. Petersenb2b465e2009-10-29 22:32:26 -0400899 static unsigned char cap[] = { SHOST_DIX_TYPE0_PROTECTION,
900 SHOST_DIX_TYPE1_PROTECTION,
901 SHOST_DIX_TYPE2_PROTECTION,
902 SHOST_DIX_TYPE3_PROTECTION };
903
Martin K. Petersen4d248342012-09-26 22:39:44 -0400904 if (target_type >= ARRAY_SIZE(cap))
Martin K. Petersenfe542392012-09-21 12:44:12 -0400905 return 0;
906
Martin K. Petersenb2b465e2009-10-29 22:32:26 -0400907 return shost->prot_capabilities & cap[target_type];
Martin K. Petersen35e1a5d2009-09-18 17:33:00 -0400908#endif
Martin K. Petersen4469f982008-07-17 04:28:30 -0400909 return 0;
910}
911
912/*
913 * All DIX-capable initiators must support the T10-mandated CRC
914 * checksum. Controllers can optionally implement the IP checksum
915 * scheme which has much lower impact on system performance. Note
916 * that the main rationale for the checksum is to match integrity
917 * metadata with data. Detecting bit errors are a job for ECC memory
918 * and buses.
919 */
920
921enum scsi_host_guard_type {
922 SHOST_DIX_GUARD_CRC = 1 << 0,
923 SHOST_DIX_GUARD_IP = 1 << 1,
924};
925
926static inline void scsi_host_set_guard(struct Scsi_Host *shost, unsigned char type)
927{
928 shost->prot_guard_type = type;
929}
930
931static inline unsigned char scsi_host_get_guard(struct Scsi_Host *shost)
932{
933 return shost->prot_guard_type;
934}
935
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936/* legacy interfaces */
937extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
938extern void scsi_unregister(struct Scsi_Host *);
James Bottomley47ba39e2005-07-30 11:39:53 -0500939extern int scsi_host_set_state(struct Scsi_Host *, enum scsi_host_state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
941#endif /* _SCSI_SCSI_HOST_H */