include/linux/blk.h

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 1 #ifndef _BLK_H
 2 #define _BLK_H
 3
 4 #include <linux/blkdev.h>
 5 #include <linux/locks.h>
 6 #include <linux/config.h>
 7
 8 #include <asm/spinlock.h>
 9
 10 /*
 11  * Spinlock for protecting the request queue which
 12  * is mucked around with in interrupts on potentially
 13  * multiple CPU's..
 14  */
 15 extern spinlock_t io_request_lock;
 16
 17 /*
 18  * NR_REQUEST is the number of entries in the request-queue.
 19  * NOTE that writes may use only the low 2/3 of these: reads
 20  * take precedence.
 21  */
 22 #define NR_REQUEST 64
 23
 24 /*
 25  * This is used in the elevator algorithm. We don't prioritise reads
 26  * over writes any more --- although reads are more time-critical than
 27  * writes, by treating them equally we increase filesystem throughput.
 28  * This turns out to give better overall performance. -- sct
 29  */
 30 #define IN_ORDER(s1,s2) \
 31 ((s1)->rq_dev < (s2)->rq_dev || (((s1)->rq_dev == (s2)->rq_dev && \
 32 (s1)->sector < (s2)->sector)))
 33
 34 /*
 35  * These will have to be changed to be aware of different buffer
 36  * sizes etc.. It actually needs a major cleanup.
 37  */
 38 #if defined(IDE_DRIVER) || defined(MD_DRIVER)
 39 #define SECTOR_MASK ((BLOCK_SIZE >> 9) - 1)
 40 #else
 41 #define SECTOR_MASK (blksize_size[MAJOR_NR] && \
 42  blksize_size[MAJOR_NR][MINOR(CURRENT->rq_dev)] ? \
 43  ((blksize_size[MAJOR_NR][MINOR(CURRENT->rq_dev)] >> 9) - 1) : \
 44  ((BLOCK_SIZE >> 9) - 1))
 45 #endif/* IDE_DRIVER */
 46
 47 #define SUBSECTOR(block) (CURRENT->current_nr_sectors > 0)
 48
 49 /*
 50  * Initialization functions.
 51  */
 52 externintisp16_init(void);
 53 externintcdu31a_init(void);
 54 externintacsi_init(void);
 55 externintmcd_init(void);
 56 externintmcdx_init(void);
 57 externintsbpcd_init(void);
 58 externintaztcd_init(void);
 59 externintsony535_init(void);
 60 externintgscd_init(void);
 61 externintcm206_init(void);
 62 externintoptcd_init(void);
 63 externintsjcd_init(void);
 64 externintcdi_init(void);
 65 externinthd_init(void);
 66 externintide_init(void);
 67 externintxd_init(void);
 68 externintloop_init(void);
 69 externintmd_init(void);
 70 externintap_init(void);
 71 externintddv_init(void);
 72 externintz2_init(void);
 73 externintswim3_init(void);
 74 externintps2esdi_init(void);
 75
 76 externvoidset_device_ro(kdev_t dev,int flag);
 77 voidadd_blkdev_randomness(int major);
 78
 79 externintfloppy_init(void);
 80 externvoidrd_load(void);
 81 externintrd_init(void);
 82 externint rd_doload;/* 1 = load ramdisk, 0 = don't load */
 83 externint rd_prompt;/* 1 = prompt for ramdisk, 0 = don't prompt */
 84 externint rd_image_start;/* starting block # of image */
 85
 86 #ifdef CONFIG_BLK_DEV_INITRD
 87
 88 #define INITRD_MINOR 250/* shouldn't collide with /dev/ram* too soon ... */
 89
 90 externunsigned long initrd_start,initrd_end;
 91 externint mount_initrd;/* zero if initrd should not be mounted */
 92 externint initrd_below_start_ok;/* 1 if it is not an error if initrd_start < memory_start */
 93 voidinitrd_init(void);
 94
 95 #endif
 96
 97 #define RO_IOCTLS(dev,where) \
 98  case BLKROSET: { int __val; if (!suser()) return -EACCES; \
 99  if (get_user(__val, (int *)(where))) return -EFAULT; \
 100  set_device_ro((dev),__val); return 0; } \
 101  case BLKROGET: { int __val = (is_read_only(dev) != 0) ; \
 102  return put_user(__val,(int *) (where)); }
 103
 104 #if defined(MAJOR_NR) || defined(IDE_DRIVER)
 105
 106 /*
 107  * Add entries as needed.
 108  */
 109
 110 #ifdef IDE_DRIVER
 111
 112 #define DEVICE_NR(device) (MINOR(device) >> PARTN_BITS)
 113 #define DEVICE_ON(device)/* nothing */
 114 #define DEVICE_OFF(device)/* nothing */
 115
 116 #elif (MAJOR_NR == RAMDISK_MAJOR)
 117
 118 /* ram disk */
 119 #define DEVICE_NAME"ramdisk"
 120 #define DEVICE_REQUEST rd_request
 121 #define DEVICE_NR(device) (MINOR(device))
 122 #define DEVICE_ON(device)
 123 #define DEVICE_OFF(device)
 124 #define DEVICE_NO_RANDOM
 125
 126 #elif (MAJOR_NR == Z2RAM_MAJOR)
 127
 128 /* Zorro II Ram */
 129 #define DEVICE_NAME"Z2RAM"
 130 #define DEVICE_REQUEST do_z2_request
 131 #define DEVICE_NR(device) (MINOR(device))
 132 #define DEVICE_ON(device)
 133 #define DEVICE_OFF(device)
 134
 135 #elif (MAJOR_NR == FLOPPY_MAJOR)
 136
 137 static voidfloppy_off(unsigned int nr);
 138
 139 #define DEVICE_NAME"floppy"
 140 #define DEVICE_INTR do_floppy
 141 #define DEVICE_REQUEST do_fd_request
 142 #define DEVICE_NR(device) ( (MINOR(device) & 3) | ((MINOR(device) & 0x80 ) >> 5 ))
 143 #define DEVICE_ON(device)
 144 #define DEVICE_OFF(device) floppy_off(DEVICE_NR(device))
 145
 146 #elif (MAJOR_NR == HD_MAJOR)
 147
 148 /* harddisk: timeout is 6 seconds.. */
 149 #define DEVICE_NAME"harddisk"
 150 #define DEVICE_INTR do_hd
 151 #define DEVICE_TIMEOUT HD_TIMER
 152 #define TIMEOUT_VALUE (6*HZ)
 153 #define DEVICE_REQUEST do_hd_request
 154 #define DEVICE_NR(device) (MINOR(device)>>6)
 155 #define DEVICE_ON(device)
 156 #define DEVICE_OFF(device)
 157
 158 #elif (MAJOR_NR == SCSI_DISK_MAJOR)
 159
 160 #define DEVICE_NAME"scsidisk"
 161 #define DEVICE_INTR do_sd
 162 #define TIMEOUT_VALUE (2*HZ)
 163 #define DEVICE_REQUEST do_sd_request
 164 #define DEVICE_NR(device) (MINOR(device) >> 4)
 165 #define DEVICE_ON(device)
 166 #define DEVICE_OFF(device)
 167
 168 /* Kludge to use the same number for both char and block major numbers */
 169 #elif (MAJOR_NR == MD_MAJOR) && defined(MD_DRIVER)
 170
 171 #define DEVICE_NAME"Multiple devices driver"
 172 #define DEVICE_REQUEST do_md_request
 173 #define DEVICE_NR(device) (MINOR(device))
 174 #define DEVICE_ON(device)
 175 #define DEVICE_OFF(device)
 176
 177 #elif (MAJOR_NR == SCSI_TAPE_MAJOR)
 178
 179 #define DEVICE_NAME"scsitape"
 180 #define DEVICE_INTR do_st
 181 #define DEVICE_NR(device) (MINOR(device) & 0x7f)
 182 #define DEVICE_ON(device)
 183 #define DEVICE_OFF(device)
 184
 185 #elif (MAJOR_NR == SCSI_CDROM_MAJOR)
 186
 187 #define DEVICE_NAME"CD-ROM"
 188 #define DEVICE_INTR do_sr
 189 #define DEVICE_REQUEST do_sr_request
 190 #define DEVICE_NR(device) (MINOR(device))
 191 #define DEVICE_ON(device)
 192 #define DEVICE_OFF(device)
 193
 194 #elif (MAJOR_NR == XT_DISK_MAJOR)
 195
 196 #define DEVICE_NAME"xt disk"
 197 #define DEVICE_REQUEST do_xd_request
 198 #define DEVICE_NR(device) (MINOR(device) >> 6)
 199 #define DEVICE_ON(device)
 200 #define DEVICE_OFF(device)
 201
 202 #elif (MAJOR_NR == PS2ESDI_MAJOR)
 203
 204 #define DEVICE_NAME"PS/2 ESDI"
 205 #define DEVICE_REQUEST do_ps2esdi_request
 206 #define DEVICE_NR(device) (MINOR(device) >> 6)
 207 #define DEVICE_ON(device)
 208 #define DEVICE_OFF(device)
 209
 210 #elif (MAJOR_NR == CDU31A_CDROM_MAJOR)
 211
 212 #define DEVICE_NAME"CDU31A"
 213 #define DEVICE_REQUEST do_cdu31a_request
 214 #define DEVICE_NR(device) (MINOR(device))
 215 #define DEVICE_ON(device)
 216 #define DEVICE_OFF(device)
 217
 218 #elif (MAJOR_NR == ACSI_MAJOR) && (defined(CONFIG_ATARI_ACSI) || defined(CONFIG_ATARI_ACSI_MODULE))
 219
 220 #define DEVICE_NAME"ACSI"
 221 #define DEVICE_INTR do_acsi
 222 #define DEVICE_REQUEST do_acsi_request
 223 #define DEVICE_NR(device) (MINOR(device) >> 4)
 224 #define DEVICE_ON(device)
 225 #define DEVICE_OFF(device)
 226
 227 #elif (MAJOR_NR == MITSUMI_CDROM_MAJOR)
 228
 229 #define DEVICE_NAME"Mitsumi CD-ROM"
 230 /* #define DEVICE_INTR do_mcd */
 231 #define DEVICE_REQUEST do_mcd_request
 232 #define DEVICE_NR(device) (MINOR(device))
 233 #define DEVICE_ON(device)
 234 #define DEVICE_OFF(device)
 235
 236 #elif (MAJOR_NR == MITSUMI_X_CDROM_MAJOR)
 237
 238 #define DEVICE_NAME"Mitsumi CD-ROM"
 239 /* #define DEVICE_INTR do_mcdx */
 240 #define DEVICE_REQUEST do_mcdx_request
 241 #define DEVICE_NR(device) (MINOR(device))
 242 #define DEVICE_ON(device)
 243 #define DEVICE_OFF(device)
 244
 245 #elif (MAJOR_NR == MATSUSHITA_CDROM_MAJOR)
 246
 247 #define DEVICE_NAME"Matsushita CD-ROM controller #1"
 248 #define DEVICE_REQUEST do_sbpcd_request
 249 #define DEVICE_NR(device) (MINOR(device))
 250 #define DEVICE_ON(device)
 251 #define DEVICE_OFF(device)
 252
 253 #elif (MAJOR_NR == MATSUSHITA_CDROM2_MAJOR)
 254
 255 #define DEVICE_NAME"Matsushita CD-ROM controller #2"
 256 #define DEVICE_REQUEST do_sbpcd2_request
 257 #define DEVICE_NR(device) (MINOR(device))
 258 #define DEVICE_ON(device)
 259 #define DEVICE_OFF(device)
 260
 261 #elif (MAJOR_NR == MATSUSHITA_CDROM3_MAJOR)
 262
 263 #define DEVICE_NAME"Matsushita CD-ROM controller #3"
 264 #define DEVICE_REQUEST do_sbpcd3_request
 265 #define DEVICE_NR(device) (MINOR(device))
 266 #define DEVICE_ON(device)
 267 #define DEVICE_OFF(device)
 268
 269 #elif (MAJOR_NR == MATSUSHITA_CDROM4_MAJOR)
 270
 271 #define DEVICE_NAME"Matsushita CD-ROM controller #4"
 272 #define DEVICE_REQUEST do_sbpcd4_request
 273 #define DEVICE_NR(device) (MINOR(device))
 274 #define DEVICE_ON(device)
 275 #define DEVICE_OFF(device)
 276
 277 #elif (MAJOR_NR == AZTECH_CDROM_MAJOR)
 278
 279 #define DEVICE_NAME"Aztech CD-ROM"
 280 #define DEVICE_REQUEST do_aztcd_request
 281 #define DEVICE_NR(device) (MINOR(device))
 282 #define DEVICE_ON(device)
 283 #define DEVICE_OFF(device)
 284
 285 #elif (MAJOR_NR == CDU535_CDROM_MAJOR)
 286
 287 #define DEVICE_NAME"SONY-CDU535"
 288 #define DEVICE_INTR do_cdu535
 289 #define DEVICE_REQUEST do_cdu535_request
 290 #define DEVICE_NR(device) (MINOR(device))
 291 #define DEVICE_ON(device)
 292 #define DEVICE_OFF(device)
 293
 294 #elif (MAJOR_NR == GOLDSTAR_CDROM_MAJOR)
 295
 296 #define DEVICE_NAME"Goldstar R420"
 297 #define DEVICE_REQUEST do_gscd_request
 298 #define DEVICE_NR(device) (MINOR(device))
 299 #define DEVICE_ON(device)
 300 #define DEVICE_OFF(device)
 301
 302 #elif (MAJOR_NR == CM206_CDROM_MAJOR)
 303 #define DEVICE_NAME"Philips/LMS cd-rom cm206"
 304 #define DEVICE_REQUEST do_cm206_request
 305 #define DEVICE_NR(device) (MINOR(device))
 306 #define DEVICE_ON(device)
 307 #define DEVICE_OFF(device)
 308
 309 #elif (MAJOR_NR == OPTICS_CDROM_MAJOR)
 310
 311 #define DEVICE_NAME"DOLPHIN 8000AT CD-ROM"
 312 #define DEVICE_REQUEST do_optcd_request
 313 #define DEVICE_NR(device) (MINOR(device))
 314 #define DEVICE_ON(device)
 315 #define DEVICE_OFF(device)
 316
 317 #elif (MAJOR_NR == SANYO_CDROM_MAJOR)
 318
 319 #define DEVICE_NAME"Sanyo H94A CD-ROM"
 320 #define DEVICE_REQUEST do_sjcd_request
 321 #define DEVICE_NR(device) (MINOR(device))
 322 #define DEVICE_ON(device)
 323 #define DEVICE_OFF(device)
 324
 325 #elif (MAJOR_NR == APBLOCK_MAJOR)
 326
 327 #define DEVICE_NAME"apblock"
 328 #define DEVICE_REQUEST ap_request
 329 #define DEVICE_NR(device) (MINOR(device))
 330 #define DEVICE_ON(device)
 331 #define DEVICE_OFF(device)
 332
 333 #elif (MAJOR_NR == DDV_MAJOR)
 334
 335 #define DEVICE_NAME"ddv"
 336 #define DEVICE_REQUEST ddv_request
 337 #define DEVICE_NR(device) (MINOR(device)>>PARTN_BITS)
 338 #define DEVICE_ON(device)
 339 #define DEVICE_OFF(device)
 340
 341 #endif/* MAJOR_NR == whatever */
 342
 343 #if (MAJOR_NR != SCSI_TAPE_MAJOR)
 344 #if !defined(IDE_DRIVER)
 345
 346 #ifndef CURRENT
 347 #define CURRENT (blk_dev[MAJOR_NR].current_request)
 348 #endif
 349
 350 #define CURRENT_DEV DEVICE_NR(CURRENT->rq_dev)
 351
 352 #ifdef DEVICE_INTR
 353 static void(*DEVICE_INTR)(void) = NULL;
 354 #endif
 355 #ifdef DEVICE_TIMEOUT
 356
 357 #define SET_TIMER \
 358 ((timer_table[DEVICE_TIMEOUT].expires = jiffies + TIMEOUT_VALUE), \
 359 (timer_active |= 1<<DEVICE_TIMEOUT))
 360
 361 #define CLEAR_TIMER \
 362 timer_active &= ~(1<<DEVICE_TIMEOUT)
 363
 364 #define SET_INTR(x) \
 365 if ((DEVICE_INTR = (x)) != NULL) \
 366  SET_TIMER; \
 367 else \
 368  CLEAR_TIMER;
 369
 370 #else
 371
 372 #define SET_INTR(x) (DEVICE_INTR = (x))
 373
 374 #endif/* DEVICE_TIMEOUT */
 375
 376 static void(DEVICE_REQUEST)(void);
 377
 378 #ifdef DEVICE_INTR
 379 #define CLEAR_INTR SET_INTR(NULL)
 380 #else
 381 #define CLEAR_INTR
 382 #endif
 383
 384 #define INIT_REQUEST \
 385  if (!CURRENT) {\
 386  CLEAR_INTR; \
 387  return; \
 388  } \
 389  if (MAJOR(CURRENT->rq_dev) != MAJOR_NR) \
 390  panic(DEVICE_NAME": request list destroyed"); \
 391  if (CURRENT->bh) { \
 392  if (!buffer_locked(CURRENT->bh)) \
 393  panic(DEVICE_NAME": block not locked"); \
 394  }
 395
 396 #endif/* !defined(IDE_DRIVER) */
 397
 398 /* end_request() - SCSI devices have their own version */
 399 /* - IDE drivers have their own copy too */
 400
 401 #if ! SCSI_BLK_MAJOR(MAJOR_NR)
 402
 403 /*
 404  * The [*_]end_request() handler has to be called with the request queue
 405  * spinlock aquired. All functions called within end_request() _must be_
 406  * atomic.
 407  */
 408 #if defined(IDE_DRIVER) && !defined(_IDE_C)/* shared copy for IDE modules */
 409 voidide_end_request(byte uptodate, ide_hwgroup_t *hwgroup);
 410 #else
 411
 412 #ifdef IDE_DRIVER
 413 voidide_end_request(byte uptodate, ide_hwgroup_t *hwgroup) {
 414 struct request *req = hwgroup->rq;
 415 #else
 416 static voidend_request(int uptodate) {
 417 struct request *req = CURRENT;
 418 #endif/* IDE_DRIVER */
 419 struct buffer_head * bh;
 420 int nsect;
 421
 422  req->errors =0;
 423 if(!uptodate) {
 424 printk("end_request: I/O error, dev %s, sector %lu\n",
 425 kdevname(req->rq_dev), req->sector);
 426 if((bh = req->bh) != NULL) {
 427  nsect = bh->b_size >>9;
 428  req->nr_sectors--;
 429  req->nr_sectors &= ~(nsect -1);
 430  req->sector += nsect;
 431  req->sector &= ~(nsect -1);
 432 }
 433 }
 434
 435 if((bh = req->bh) != NULL) {
 436  req->bh = bh->b_reqnext;
 437  bh->b_reqnext = NULL;
 438  bh->b_end_io(bh, uptodate);
 439 if((bh = req->bh) != NULL) {
 440  req->current_nr_sectors = bh->b_size >>9;
 441 if(req->nr_sectors < req->current_nr_sectors) {
 442  req->nr_sectors = req->current_nr_sectors;
 443 printk("end_request: buffer-list destroyed\n");
 444 }
 445  req->buffer = bh->b_data;
 446 return;
 447 }
 448 }
 449 #ifndef DEVICE_NO_RANDOM
 450 add_blkdev_randomness(MAJOR(req->rq_dev));
 451 #endif
 452 #ifdef IDE_DRIVER
 453  hwgroup->drive->queue = req->next;
 454  blk_dev[MAJOR(req->rq_dev)].current_request = NULL;
 455  hwgroup->rq = NULL;
 456 #else
 457 DEVICE_OFF(req->rq_dev);
 458  CURRENT = req->next;
 459 #endif/* IDE_DRIVER */
 460 if(req->sem != NULL)
 461 up(req->sem);
 462  req->rq_status = RQ_INACTIVE;
 463 wake_up(&wait_for_request);
 464 }
 465 #endif/* defined(IDE_DRIVER) && !defined(_IDE_C) */
 466 #endif/* ! SCSI_BLK_MAJOR(MAJOR_NR) */
 467 #endif/* (MAJOR_NR != SCSI_TAPE_MAJOR) */
 468
 469 #endif/* defined(MAJOR_NR) || defined(IDE_DRIVER) */
 470
 471 #endif/* _BLK_H */