Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * hosts.c Copyright (C) 1992 Drew Eckhardt |
| 3 | * Copyright (C) 1993, 1994, 1995 Eric Youngdale |
| 4 | * Copyright (C) 2002-2003 Christoph Hellwig |
| 5 | * |
| 6 | * mid to lowlevel SCSI driver interface |
| 7 | * Initial versions: Drew Eckhardt |
| 8 | * Subsequent revisions: Eric Youngdale |
| 9 | * |
| 10 | * <drew@colorado.edu> |
| 11 | * |
| 12 | * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli |
| 13 | * Added QLOGIC QLA1280 SCSI controller kernel host support. |
| 14 | * August 4, 1999 Fred Lewis, Intel DuPont |
| 15 | * |
| 16 | * Updated to reflect the new initialization scheme for the higher |
| 17 | * level of scsi drivers (sd/sr/st) |
| 18 | * September 17, 2000 Torben Mathiasen <tmm@image.dk> |
| 19 | * |
| 20 | * Restructured scsi_host lists and associated functions. |
| 21 | * September 04, 2002 Mike Anderson (andmike@us.ibm.com) |
| 22 | */ |
| 23 | |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/blkdev.h> |
| 26 | #include <linux/kernel.h> |
Christoph Hellwig | c5478de | 2005-09-06 14:04:26 +0200 | [diff] [blame] | 27 | #include <linux/kthread.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | #include <linux/string.h> |
| 29 | #include <linux/mm.h> |
| 30 | #include <linux/init.h> |
| 31 | #include <linux/completion.h> |
| 32 | #include <linux/transport_class.h> |
Russell King | d052d1b | 2005-10-29 19:07:23 +0100 | [diff] [blame] | 33 | #include <linux/platform_device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
| 35 | #include <scsi/scsi_device.h> |
| 36 | #include <scsi/scsi_host.h> |
| 37 | #include <scsi/scsi_transport.h> |
| 38 | |
| 39 | #include "scsi_priv.h" |
| 40 | #include "scsi_logging.h" |
| 41 | |
| 42 | |
| 43 | static int scsi_host_next_hn; /* host_no for next new host */ |
| 44 | |
| 45 | |
| 46 | static void scsi_host_cls_release(struct class_device *class_dev) |
| 47 | { |
| 48 | put_device(&class_to_shost(class_dev)->shost_gendev); |
| 49 | } |
| 50 | |
| 51 | static struct class shost_class = { |
| 52 | .name = "scsi_host", |
| 53 | .release = scsi_host_cls_release, |
| 54 | }; |
| 55 | |
| 56 | /** |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 57 | * scsi_host_set_state - Take the given host through the host |
| 58 | * state model. |
| 59 | * @shost: scsi host to change the state of. |
| 60 | * @state: state to change to. |
| 61 | * |
| 62 | * Returns zero if unsuccessful or an error if the requested |
| 63 | * transition is illegal. |
| 64 | **/ |
| 65 | int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) |
| 66 | { |
| 67 | enum scsi_host_state oldstate = shost->shost_state; |
| 68 | |
| 69 | if (state == oldstate) |
| 70 | return 0; |
| 71 | |
| 72 | switch (state) { |
| 73 | case SHOST_CREATED: |
| 74 | /* There are no legal states that come back to |
| 75 | * created. This is the manually initialised start |
| 76 | * state */ |
| 77 | goto illegal; |
| 78 | |
| 79 | case SHOST_RUNNING: |
| 80 | switch (oldstate) { |
| 81 | case SHOST_CREATED: |
| 82 | case SHOST_RECOVERY: |
| 83 | break; |
| 84 | default: |
| 85 | goto illegal; |
| 86 | } |
| 87 | break; |
| 88 | |
| 89 | case SHOST_RECOVERY: |
| 90 | switch (oldstate) { |
| 91 | case SHOST_RUNNING: |
| 92 | break; |
| 93 | default: |
| 94 | goto illegal; |
| 95 | } |
| 96 | break; |
| 97 | |
| 98 | case SHOST_CANCEL: |
| 99 | switch (oldstate) { |
| 100 | case SHOST_CREATED: |
| 101 | case SHOST_RUNNING: |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 102 | case SHOST_CANCEL_RECOVERY: |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 103 | break; |
| 104 | default: |
| 105 | goto illegal; |
| 106 | } |
| 107 | break; |
| 108 | |
| 109 | case SHOST_DEL: |
| 110 | switch (oldstate) { |
| 111 | case SHOST_CANCEL: |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 112 | case SHOST_DEL_RECOVERY: |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 113 | break; |
| 114 | default: |
| 115 | goto illegal; |
| 116 | } |
| 117 | break; |
| 118 | |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 119 | case SHOST_CANCEL_RECOVERY: |
| 120 | switch (oldstate) { |
| 121 | case SHOST_CANCEL: |
| 122 | case SHOST_RECOVERY: |
| 123 | break; |
| 124 | default: |
| 125 | goto illegal; |
| 126 | } |
| 127 | break; |
| 128 | |
| 129 | case SHOST_DEL_RECOVERY: |
| 130 | switch (oldstate) { |
| 131 | case SHOST_CANCEL_RECOVERY: |
| 132 | break; |
| 133 | default: |
| 134 | goto illegal; |
| 135 | } |
| 136 | break; |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 137 | } |
| 138 | shost->shost_state = state; |
| 139 | return 0; |
| 140 | |
| 141 | illegal: |
| 142 | SCSI_LOG_ERROR_RECOVERY(1, |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 143 | shost_printk(KERN_ERR, shost, |
| 144 | "Illegal host state transition" |
| 145 | "%s->%s\n", |
| 146 | scsi_host_state_name(oldstate), |
| 147 | scsi_host_state_name(state))); |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 148 | return -EINVAL; |
| 149 | } |
| 150 | EXPORT_SYMBOL(scsi_host_set_state); |
| 151 | |
| 152 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | * scsi_remove_host - remove a scsi host |
| 154 | * @shost: a pointer to a scsi host to remove |
| 155 | **/ |
| 156 | void scsi_remove_host(struct Scsi_Host *shost) |
| 157 | { |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 158 | unsigned long flags; |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 159 | mutex_lock(&shost->scan_mutex); |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 160 | spin_lock_irqsave(shost->host_lock, flags); |
| 161 | if (scsi_host_set_state(shost, SHOST_CANCEL)) |
| 162 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) { |
| 163 | spin_unlock_irqrestore(shost->host_lock, flags); |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 164 | mutex_unlock(&shost->scan_mutex); |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 165 | return; |
| 166 | } |
| 167 | spin_unlock_irqrestore(shost->host_lock, flags); |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 168 | mutex_unlock(&shost->scan_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | scsi_forget_host(shost); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | scsi_proc_host_rm(shost); |
| 171 | |
James Bottomley | 939647e | 2005-09-18 15:05:20 -0500 | [diff] [blame] | 172 | spin_lock_irqsave(shost->host_lock, flags); |
| 173 | if (scsi_host_set_state(shost, SHOST_DEL)) |
| 174 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY)); |
| 175 | spin_unlock_irqrestore(shost->host_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | |
| 177 | transport_unregister_device(&shost->shost_gendev); |
| 178 | class_device_unregister(&shost->shost_classdev); |
| 179 | device_del(&shost->shost_gendev); |
James Bottomley | 9e70592 | 2005-10-02 12:59:49 -0500 | [diff] [blame] | 180 | scsi_proc_hostdir_rm(shost->hostt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | } |
| 182 | EXPORT_SYMBOL(scsi_remove_host); |
| 183 | |
| 184 | /** |
| 185 | * scsi_add_host - add a scsi host |
| 186 | * @shost: scsi host pointer to add |
| 187 | * @dev: a struct device of type scsi class |
| 188 | * |
| 189 | * Return value: |
| 190 | * 0 on success / != 0 for error |
| 191 | **/ |
| 192 | int scsi_add_host(struct Scsi_Host *shost, struct device *dev) |
| 193 | { |
| 194 | struct scsi_host_template *sht = shost->hostt; |
| 195 | int error = -EINVAL; |
| 196 | |
| 197 | printk(KERN_INFO "scsi%d : %s\n", shost->host_no, |
| 198 | sht->info ? sht->info(shost) : sht->name); |
| 199 | |
| 200 | if (!shost->can_queue) { |
| 201 | printk(KERN_ERR "%s: can_queue = 0 no longer supported\n", |
| 202 | sht->name); |
| 203 | goto out; |
| 204 | } |
| 205 | |
| 206 | if (!shost->shost_gendev.parent) |
| 207 | shost->shost_gendev.parent = dev ? dev : &platform_bus; |
| 208 | |
| 209 | error = device_add(&shost->shost_gendev); |
| 210 | if (error) |
| 211 | goto out; |
| 212 | |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 213 | scsi_host_set_state(shost, SHOST_RUNNING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | get_device(shost->shost_gendev.parent); |
| 215 | |
| 216 | error = class_device_add(&shost->shost_classdev); |
| 217 | if (error) |
| 218 | goto out_del_gendev; |
| 219 | |
| 220 | get_device(&shost->shost_gendev); |
| 221 | |
| 222 | if (shost->transportt->host_size && |
FUJITA Tomonori | c000c43 | 2007-08-01 08:40:27 +0900 | [diff] [blame] | 223 | (shost->shost_data = kzalloc(shost->transportt->host_size, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | GFP_KERNEL)) == NULL) |
| 225 | goto out_del_classdev; |
| 226 | |
| 227 | if (shost->transportt->create_work_queue) { |
| 228 | snprintf(shost->work_q_name, KOBJ_NAME_LEN, "scsi_wq_%d", |
| 229 | shost->host_no); |
| 230 | shost->work_q = create_singlethread_workqueue( |
| 231 | shost->work_q_name); |
| 232 | if (!shost->work_q) |
| 233 | goto out_free_shost_data; |
| 234 | } |
| 235 | |
| 236 | error = scsi_sysfs_add_host(shost); |
| 237 | if (error) |
| 238 | goto out_destroy_host; |
| 239 | |
| 240 | scsi_proc_host_add(shost); |
| 241 | return error; |
| 242 | |
| 243 | out_destroy_host: |
| 244 | if (shost->work_q) |
| 245 | destroy_workqueue(shost->work_q); |
| 246 | out_free_shost_data: |
| 247 | kfree(shost->shost_data); |
| 248 | out_del_classdev: |
| 249 | class_device_del(&shost->shost_classdev); |
| 250 | out_del_gendev: |
| 251 | device_del(&shost->shost_gendev); |
| 252 | out: |
| 253 | return error; |
| 254 | } |
| 255 | EXPORT_SYMBOL(scsi_add_host); |
| 256 | |
| 257 | static void scsi_host_dev_release(struct device *dev) |
| 258 | { |
| 259 | struct Scsi_Host *shost = dev_to_shost(dev); |
| 260 | struct device *parent = dev->parent; |
| 261 | |
Christoph Hellwig | c5478de | 2005-09-06 14:04:26 +0200 | [diff] [blame] | 262 | if (shost->ehandler) |
| 263 | kthread_stop(shost->ehandler); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | if (shost->work_q) |
| 265 | destroy_workqueue(shost->work_q); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 266 | if (shost->uspace_req_q) { |
| 267 | kfree(shost->uspace_req_q->queuedata); |
| 268 | scsi_free_queue(shost->uspace_req_q); |
| 269 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | scsi_destroy_command_freelist(shost); |
James Bottomley | 86e33a2 | 2006-08-30 09:45:51 -0400 | [diff] [blame] | 272 | if (shost->bqt) |
| 273 | blk_free_tags(shost->bqt); |
| 274 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | kfree(shost->shost_data); |
| 276 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | if (parent) |
| 278 | put_device(parent); |
| 279 | kfree(shost); |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * scsi_host_alloc - register a scsi host adapter instance. |
| 284 | * @sht: pointer to scsi host template |
| 285 | * @privsize: extra bytes to allocate for driver |
| 286 | * |
| 287 | * Note: |
| 288 | * Allocate a new Scsi_Host and perform basic initialization. |
| 289 | * The host is not published to the scsi midlayer until scsi_add_host |
| 290 | * is called. |
| 291 | * |
| 292 | * Return value: |
| 293 | * Pointer to a new Scsi_Host |
| 294 | **/ |
| 295 | struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) |
| 296 | { |
| 297 | struct Scsi_Host *shost; |
Al Viro | c53033f | 2005-10-21 03:22:08 -0400 | [diff] [blame] | 298 | gfp_t gfp_mask = GFP_KERNEL; |
| 299 | int rval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | |
| 301 | if (sht->unchecked_isa_dma && privsize) |
| 302 | gfp_mask |= __GFP_DMA; |
| 303 | |
Jes Sorensen | 24669f75 | 2006-01-16 10:31:18 -0500 | [diff] [blame] | 304 | shost = kzalloc(sizeof(struct Scsi_Host) + privsize, gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | if (!shost) |
| 306 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | |
Christoph Hellwig | 4f777ed2 | 2006-11-04 20:11:36 +0100 | [diff] [blame] | 308 | shost->host_lock = &shost->default_lock; |
| 309 | spin_lock_init(shost->host_lock); |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 310 | shost->shost_state = SHOST_CREATED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | INIT_LIST_HEAD(&shost->__devices); |
| 312 | INIT_LIST_HEAD(&shost->__targets); |
| 313 | INIT_LIST_HEAD(&shost->eh_cmd_q); |
| 314 | INIT_LIST_HEAD(&shost->starved_list); |
| 315 | init_waitqueue_head(&shost->host_wait); |
| 316 | |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 317 | mutex_init(&shost->scan_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | |
| 319 | shost->host_no = scsi_host_next_hn++; /* XXX(hch): still racy */ |
| 320 | shost->dma_channel = 0xff; |
| 321 | |
| 322 | /* These three are default values which can be overridden */ |
| 323 | shost->max_channel = 0; |
| 324 | shost->max_id = 8; |
| 325 | shost->max_lun = 8; |
| 326 | |
| 327 | /* Give each shost a default transportt */ |
| 328 | shost->transportt = &blank_transport_template; |
| 329 | |
| 330 | /* |
| 331 | * All drivers right now should be able to handle 12 byte |
| 332 | * commands. Every so often there are requests for 16 byte |
| 333 | * commands, but individual low-level drivers need to certify that |
| 334 | * they actually do something sensible with such commands. |
| 335 | */ |
| 336 | shost->max_cmd_len = 12; |
| 337 | shost->hostt = sht; |
| 338 | shost->this_id = sht->this_id; |
| 339 | shost->can_queue = sht->can_queue; |
| 340 | shost->sg_tablesize = sht->sg_tablesize; |
| 341 | shost->cmd_per_lun = sht->cmd_per_lun; |
| 342 | shost->unchecked_isa_dma = sht->unchecked_isa_dma; |
| 343 | shost->use_clustering = sht->use_clustering; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | shost->ordered_tag = sht->ordered_tag; |
FUJITA Tomonori | 5dc2b89 | 2007-09-01 02:02:20 +0900 | [diff] [blame] | 345 | shost->active_mode = sht->supported_mode; |
FUJITA Tomonori | 9cb83c7 | 2007-10-16 11:24:32 +0200 | [diff] [blame] | 346 | shost->use_sg_chaining = sht->use_sg_chaining; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | |
James Bottomley | 7a39ac3 | 2007-09-25 22:45:53 -0500 | [diff] [blame] | 348 | if (sht->supported_mode == MODE_UNKNOWN) |
| 349 | /* means we didn't set it ... default to INITIATOR */ |
| 350 | shost->active_mode = MODE_INITIATOR; |
| 351 | else |
| 352 | shost->active_mode = sht->supported_mode; |
| 353 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | if (sht->max_host_blocked) |
| 355 | shost->max_host_blocked = sht->max_host_blocked; |
| 356 | else |
| 357 | shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED; |
| 358 | |
| 359 | /* |
| 360 | * If the driver imposes no hard sector transfer limit, start at |
| 361 | * machine infinity initially. |
| 362 | */ |
| 363 | if (sht->max_sectors) |
| 364 | shost->max_sectors = sht->max_sectors; |
| 365 | else |
| 366 | shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS; |
| 367 | |
| 368 | /* |
| 369 | * assume a 4GB boundary, if not set |
| 370 | */ |
| 371 | if (sht->dma_boundary) |
| 372 | shost->dma_boundary = sht->dma_boundary; |
| 373 | else |
| 374 | shost->dma_boundary = 0xffffffff; |
| 375 | |
| 376 | rval = scsi_setup_command_freelist(shost); |
| 377 | if (rval) |
| 378 | goto fail_kfree; |
| 379 | |
| 380 | device_initialize(&shost->shost_gendev); |
| 381 | snprintf(shost->shost_gendev.bus_id, BUS_ID_SIZE, "host%d", |
| 382 | shost->host_no); |
| 383 | shost->shost_gendev.release = scsi_host_dev_release; |
| 384 | |
| 385 | class_device_initialize(&shost->shost_classdev); |
| 386 | shost->shost_classdev.dev = &shost->shost_gendev; |
| 387 | shost->shost_classdev.class = &shost_class; |
| 388 | snprintf(shost->shost_classdev.class_id, BUS_ID_SIZE, "host%d", |
| 389 | shost->host_no); |
| 390 | |
Christoph Hellwig | c5478de | 2005-09-06 14:04:26 +0200 | [diff] [blame] | 391 | shost->ehandler = kthread_run(scsi_error_handler, shost, |
| 392 | "scsi_eh_%d", shost->host_no); |
| 393 | if (IS_ERR(shost->ehandler)) { |
| 394 | rval = PTR_ERR(shost->ehandler); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | goto fail_destroy_freelist; |
Christoph Hellwig | c5478de | 2005-09-06 14:04:26 +0200 | [diff] [blame] | 396 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | |
| 398 | scsi_proc_hostdir_add(shost->hostt); |
| 399 | return shost; |
| 400 | |
| 401 | fail_destroy_freelist: |
| 402 | scsi_destroy_command_freelist(shost); |
| 403 | fail_kfree: |
| 404 | kfree(shost); |
| 405 | return NULL; |
| 406 | } |
| 407 | EXPORT_SYMBOL(scsi_host_alloc); |
| 408 | |
| 409 | struct Scsi_Host *scsi_register(struct scsi_host_template *sht, int privsize) |
| 410 | { |
| 411 | struct Scsi_Host *shost = scsi_host_alloc(sht, privsize); |
| 412 | |
| 413 | if (!sht->detect) { |
| 414 | printk(KERN_WARNING "scsi_register() called on new-style " |
| 415 | "template for driver %s\n", sht->name); |
| 416 | dump_stack(); |
| 417 | } |
| 418 | |
| 419 | if (shost) |
| 420 | list_add_tail(&shost->sht_legacy_list, &sht->legacy_hosts); |
| 421 | return shost; |
| 422 | } |
| 423 | EXPORT_SYMBOL(scsi_register); |
| 424 | |
| 425 | void scsi_unregister(struct Scsi_Host *shost) |
| 426 | { |
| 427 | list_del(&shost->sht_legacy_list); |
| 428 | scsi_host_put(shost); |
| 429 | } |
| 430 | EXPORT_SYMBOL(scsi_unregister); |
| 431 | |
| 432 | /** |
| 433 | * scsi_host_lookup - get a reference to a Scsi_Host by host no |
| 434 | * |
| 435 | * @hostnum: host number to locate |
| 436 | * |
| 437 | * Return value: |
| 438 | * A pointer to located Scsi_Host or NULL. |
| 439 | **/ |
| 440 | struct Scsi_Host *scsi_host_lookup(unsigned short hostnum) |
| 441 | { |
| 442 | struct class *class = &shost_class; |
| 443 | struct class_device *cdev; |
| 444 | struct Scsi_Host *shost = ERR_PTR(-ENXIO), *p; |
| 445 | |
Greg Kroah-Hartman | b7bb125 | 2007-04-09 11:52:31 -0400 | [diff] [blame] | 446 | down(&class->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | list_for_each_entry(cdev, &class->children, node) { |
| 448 | p = class_to_shost(cdev); |
| 449 | if (p->host_no == hostnum) { |
| 450 | shost = scsi_host_get(p); |
| 451 | break; |
| 452 | } |
| 453 | } |
Greg Kroah-Hartman | b7bb125 | 2007-04-09 11:52:31 -0400 | [diff] [blame] | 454 | up(&class->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | |
| 456 | return shost; |
| 457 | } |
| 458 | EXPORT_SYMBOL(scsi_host_lookup); |
| 459 | |
| 460 | /** |
| 461 | * scsi_host_get - inc a Scsi_Host ref count |
| 462 | * @shost: Pointer to Scsi_Host to inc. |
| 463 | **/ |
| 464 | struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost) |
| 465 | { |
Mike Anderson | d330187 | 2005-06-16 11:12:38 -0700 | [diff] [blame] | 466 | if ((shost->shost_state == SHOST_DEL) || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | !get_device(&shost->shost_gendev)) |
| 468 | return NULL; |
| 469 | return shost; |
| 470 | } |
| 471 | EXPORT_SYMBOL(scsi_host_get); |
| 472 | |
| 473 | /** |
| 474 | * scsi_host_put - dec a Scsi_Host ref count |
| 475 | * @shost: Pointer to Scsi_Host to dec. |
| 476 | **/ |
| 477 | void scsi_host_put(struct Scsi_Host *shost) |
| 478 | { |
| 479 | put_device(&shost->shost_gendev); |
| 480 | } |
| 481 | EXPORT_SYMBOL(scsi_host_put); |
| 482 | |
| 483 | int scsi_init_hosts(void) |
| 484 | { |
| 485 | return class_register(&shost_class); |
| 486 | } |
| 487 | |
| 488 | void scsi_exit_hosts(void) |
| 489 | { |
| 490 | class_unregister(&shost_class); |
| 491 | } |
| 492 | |
| 493 | int scsi_is_host_device(const struct device *dev) |
| 494 | { |
| 495 | return dev->release == scsi_host_dev_release; |
| 496 | } |
| 497 | EXPORT_SYMBOL(scsi_is_host_device); |
| 498 | |
| 499 | /** |
| 500 | * scsi_queue_work - Queue work to the Scsi_Host workqueue. |
| 501 | * @shost: Pointer to Scsi_Host. |
| 502 | * @work: Work to queue for execution. |
| 503 | * |
| 504 | * Return value: |
Michael Reed | dd7e2f2 | 2006-08-04 12:09:24 -0500 | [diff] [blame] | 505 | * 1 - work queued for execution |
| 506 | * 0 - work is already queued |
| 507 | * -EINVAL - work queue doesn't exist |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | **/ |
| 509 | int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work) |
| 510 | { |
| 511 | if (unlikely(!shost->work_q)) { |
| 512 | printk(KERN_ERR |
| 513 | "ERROR: Scsi host '%s' attempted to queue scsi-work, " |
| 514 | "when no workqueue created.\n", shost->hostt->name); |
| 515 | dump_stack(); |
| 516 | |
| 517 | return -EINVAL; |
| 518 | } |
| 519 | |
| 520 | return queue_work(shost->work_q, work); |
| 521 | } |
| 522 | EXPORT_SYMBOL_GPL(scsi_queue_work); |
| 523 | |
| 524 | /** |
| 525 | * scsi_flush_work - Flush a Scsi_Host's workqueue. |
| 526 | * @shost: Pointer to Scsi_Host. |
| 527 | **/ |
| 528 | void scsi_flush_work(struct Scsi_Host *shost) |
| 529 | { |
| 530 | if (!shost->work_q) { |
| 531 | printk(KERN_ERR |
| 532 | "ERROR: Scsi host '%s' attempted to flush scsi-work, " |
| 533 | "when no workqueue created.\n", shost->hostt->name); |
| 534 | dump_stack(); |
| 535 | return; |
| 536 | } |
| 537 | |
| 538 | flush_workqueue(shost->work_q); |
| 539 | } |
| 540 | EXPORT_SYMBOL_GPL(scsi_flush_work); |