Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/s390/cio/device_pgid.c |
| 3 | * |
| 4 | * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH, |
| 5 | * IBM Corporation |
Cornelia Huck | 4ce3b30 | 2006-01-14 13:21:04 -0800 | [diff] [blame] | 6 | * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * Martin Schwidefsky (schwidefsky@de.ibm.com) |
| 8 | * |
| 9 | * Path Group ID functions. |
| 10 | */ |
| 11 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/module.h> |
| 13 | #include <linux/init.h> |
| 14 | |
| 15 | #include <asm/ccwdev.h> |
| 16 | #include <asm/cio.h> |
| 17 | #include <asm/delay.h> |
| 18 | #include <asm/lowcore.h> |
| 19 | |
| 20 | #include "cio.h" |
| 21 | #include "cio_debug.h" |
| 22 | #include "css.h" |
| 23 | #include "device.h" |
Cornelia Huck | 6810a2b | 2006-01-06 00:19:13 -0800 | [diff] [blame] | 24 | #include "ioasm.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | /* |
| 27 | * Start Sense Path Group ID helper function. Used in ccw_device_recog |
| 28 | * and ccw_device_sense_pgid. |
| 29 | */ |
| 30 | static int |
| 31 | __ccw_device_sense_pgid_start(struct ccw_device *cdev) |
| 32 | { |
| 33 | struct subchannel *sch; |
| 34 | struct ccw1 *ccw; |
| 35 | int ret; |
| 36 | |
| 37 | sch = to_subchannel(cdev->dev.parent); |
| 38 | /* Setup sense path group id channel program. */ |
| 39 | ccw = cdev->private->iccws; |
| 40 | ccw->cmd_code = CCW_CMD_SENSE_PGID; |
| 41 | ccw->cda = (__u32) __pa (&cdev->private->pgid); |
| 42 | ccw->count = sizeof (struct pgid); |
| 43 | ccw->flags = CCW_FLAG_SLI; |
| 44 | |
| 45 | /* Reset device status. */ |
| 46 | memset(&cdev->private->irb, 0, sizeof(struct irb)); |
| 47 | /* Try on every path. */ |
| 48 | ret = -ENODEV; |
| 49 | while (cdev->private->imask != 0) { |
| 50 | /* Try every path multiple times. */ |
| 51 | if (cdev->private->iretry > 0) { |
| 52 | cdev->private->iretry--; |
| 53 | ret = cio_start (sch, cdev->private->iccws, |
| 54 | cdev->private->imask); |
| 55 | /* ret is 0, -EBUSY, -EACCES or -ENODEV */ |
| 56 | if (ret != -EACCES) |
| 57 | return ret; |
| 58 | CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel " |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 59 | "0.%x.%04x, lpm %02X, became 'not " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | "operational'\n", |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 61 | cdev->private->devno, sch->schid.ssid, |
| 62 | sch->schid.sch_no, cdev->private->imask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | |
| 64 | } |
| 65 | cdev->private->imask >>= 1; |
| 66 | cdev->private->iretry = 5; |
| 67 | } |
| 68 | return ret; |
| 69 | } |
| 70 | |
| 71 | void |
| 72 | ccw_device_sense_pgid_start(struct ccw_device *cdev) |
| 73 | { |
| 74 | int ret; |
| 75 | |
| 76 | cdev->private->state = DEV_STATE_SENSE_PGID; |
| 77 | cdev->private->imask = 0x80; |
| 78 | cdev->private->iretry = 5; |
| 79 | memset (&cdev->private->pgid, 0, sizeof (struct pgid)); |
| 80 | ret = __ccw_device_sense_pgid_start(cdev); |
| 81 | if (ret && ret != -EBUSY) |
| 82 | ccw_device_sense_pgid_done(cdev, ret); |
| 83 | } |
| 84 | |
| 85 | /* |
| 86 | * Called from interrupt context to check if a valid answer |
| 87 | * to Sense Path Group ID was received. |
| 88 | */ |
| 89 | static int |
| 90 | __ccw_device_check_sense_pgid(struct ccw_device *cdev) |
| 91 | { |
| 92 | struct subchannel *sch; |
| 93 | struct irb *irb; |
| 94 | |
| 95 | sch = to_subchannel(cdev->dev.parent); |
| 96 | irb = &cdev->private->irb; |
| 97 | if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) |
| 98 | return -ETIME; |
| 99 | if (irb->esw.esw0.erw.cons && |
| 100 | (irb->ecw[0]&(SNS0_CMD_REJECT|SNS0_INTERVENTION_REQ))) { |
| 101 | /* |
| 102 | * If the device doesn't support the Sense Path Group ID |
| 103 | * command further retries wouldn't help ... |
| 104 | */ |
| 105 | return -EOPNOTSUPP; |
| 106 | } |
| 107 | if (irb->esw.esw0.erw.cons) { |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 108 | CIO_MSG_EVENT(2, "SNID - device 0.%x.%04x, unit check, " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | "lpum %02X, cnt %02d, sns : " |
| 110 | "%02X%02X%02X%02X %02X%02X%02X%02X ...\n", |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 111 | cdev->private->ssid, cdev->private->devno, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | irb->esw.esw0.sublog.lpum, |
| 113 | irb->esw.esw0.erw.scnt, |
| 114 | irb->ecw[0], irb->ecw[1], |
| 115 | irb->ecw[2], irb->ecw[3], |
| 116 | irb->ecw[4], irb->ecw[5], |
| 117 | irb->ecw[6], irb->ecw[7]); |
| 118 | return -EAGAIN; |
| 119 | } |
| 120 | if (irb->scsw.cc == 3) { |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 121 | CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel 0.%x.%04x," |
| 122 | " lpm %02X, became 'not operational'\n", |
| 123 | cdev->private->devno, sch->schid.ssid, |
| 124 | sch->schid.sch_no, sch->orb.lpm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | return -EACCES; |
| 126 | } |
| 127 | if (cdev->private->pgid.inf.ps.state2 == SNID_STATE2_RESVD_ELSE) { |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 128 | CIO_MSG_EVENT(2, "SNID - Device %04x on Subchannel 0.%x.%04x " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | "is reserved by someone else\n", |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 130 | cdev->private->devno, sch->schid.ssid, |
| 131 | sch->schid.sch_no); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | return -EUSERS; |
| 133 | } |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | /* |
| 138 | * Got interrupt for Sense Path Group ID. |
| 139 | */ |
| 140 | void |
| 141 | ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event) |
| 142 | { |
| 143 | struct subchannel *sch; |
| 144 | struct irb *irb; |
| 145 | int ret; |
| 146 | |
| 147 | irb = (struct irb *) __LC_IRB; |
| 148 | /* Retry sense pgid for cc=1. */ |
| 149 | if (irb->scsw.stctl == |
| 150 | (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { |
| 151 | if (irb->scsw.cc == 1) { |
| 152 | ret = __ccw_device_sense_pgid_start(cdev); |
| 153 | if (ret && ret != -EBUSY) |
| 154 | ccw_device_sense_pgid_done(cdev, ret); |
| 155 | } |
| 156 | return; |
| 157 | } |
| 158 | if (ccw_device_accumulate_and_sense(cdev, irb) != 0) |
| 159 | return; |
| 160 | sch = to_subchannel(cdev->dev.parent); |
| 161 | ret = __ccw_device_check_sense_pgid(cdev); |
| 162 | memset(&cdev->private->irb, 0, sizeof(struct irb)); |
| 163 | switch (ret) { |
| 164 | /* 0, -ETIME, -EOPNOTSUPP, -EAGAIN, -EACCES or -EUSERS */ |
| 165 | case 0: /* Sense Path Group ID successful. */ |
| 166 | if (cdev->private->pgid.inf.ps.state1 == SNID_STATE1_RESET) |
Cornelia Huck | a28c694 | 2006-01-06 00:19:23 -0800 | [diff] [blame] | 167 | memcpy(&cdev->private->pgid, &css[0]->global_pgid, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | sizeof(struct pgid)); |
| 169 | ccw_device_sense_pgid_done(cdev, 0); |
| 170 | break; |
| 171 | case -EOPNOTSUPP: /* Sense Path Group ID not supported */ |
| 172 | ccw_device_sense_pgid_done(cdev, -EOPNOTSUPP); |
| 173 | break; |
| 174 | case -ETIME: /* Sense path group id stopped by timeout. */ |
| 175 | ccw_device_sense_pgid_done(cdev, -ETIME); |
| 176 | break; |
| 177 | case -EACCES: /* channel is not operational. */ |
| 178 | sch->lpm &= ~cdev->private->imask; |
| 179 | cdev->private->imask >>= 1; |
| 180 | cdev->private->iretry = 5; |
| 181 | /* Fall through. */ |
| 182 | case -EAGAIN: /* Try again. */ |
| 183 | ret = __ccw_device_sense_pgid_start(cdev); |
| 184 | if (ret != 0 && ret != -EBUSY) |
| 185 | ccw_device_sense_pgid_done(cdev, -ENODEV); |
| 186 | break; |
| 187 | case -EUSERS: /* device is reserved for someone else. */ |
| 188 | ccw_device_sense_pgid_done(cdev, -EUSERS); |
| 189 | break; |
| 190 | } |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * Path Group ID helper function. |
| 195 | */ |
| 196 | static int |
| 197 | __ccw_device_do_pgid(struct ccw_device *cdev, __u8 func) |
| 198 | { |
| 199 | struct subchannel *sch; |
| 200 | struct ccw1 *ccw; |
| 201 | int ret; |
| 202 | |
| 203 | sch = to_subchannel(cdev->dev.parent); |
| 204 | |
| 205 | /* Setup sense path group id channel program. */ |
| 206 | cdev->private->pgid.inf.fc = func; |
| 207 | ccw = cdev->private->iccws; |
| 208 | if (!cdev->private->flags.pgid_single) { |
| 209 | cdev->private->pgid.inf.fc |= SPID_FUNC_MULTI_PATH; |
| 210 | ccw->cmd_code = CCW_CMD_SUSPEND_RECONN; |
| 211 | ccw->cda = 0; |
| 212 | ccw->count = 0; |
| 213 | ccw->flags = CCW_FLAG_SLI | CCW_FLAG_CC; |
| 214 | ccw++; |
| 215 | } else |
| 216 | cdev->private->pgid.inf.fc |= SPID_FUNC_SINGLE_PATH; |
| 217 | |
| 218 | ccw->cmd_code = CCW_CMD_SET_PGID; |
| 219 | ccw->cda = (__u32) __pa (&cdev->private->pgid); |
| 220 | ccw->count = sizeof (struct pgid); |
| 221 | ccw->flags = CCW_FLAG_SLI; |
| 222 | |
| 223 | /* Reset device status. */ |
| 224 | memset(&cdev->private->irb, 0, sizeof(struct irb)); |
| 225 | |
| 226 | /* Try multiple times. */ |
| 227 | ret = -ENODEV; |
| 228 | if (cdev->private->iretry > 0) { |
| 229 | cdev->private->iretry--; |
| 230 | ret = cio_start (sch, cdev->private->iccws, |
| 231 | cdev->private->imask); |
| 232 | /* ret is 0, -EBUSY, -EACCES or -ENODEV */ |
| 233 | if ((ret != -EACCES) && (ret != -ENODEV)) |
| 234 | return ret; |
| 235 | } |
| 236 | /* PGID command failed on this path. Switch it off. */ |
| 237 | sch->lpm &= ~cdev->private->imask; |
| 238 | sch->vpm &= ~cdev->private->imask; |
| 239 | CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel " |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 240 | "0.%x.%04x, lpm %02X, became 'not operational'\n", |
| 241 | cdev->private->devno, sch->schid.ssid, |
| 242 | sch->schid.sch_no, cdev->private->imask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | return ret; |
| 244 | } |
| 245 | |
| 246 | /* |
| 247 | * Called from interrupt context to check if a valid answer |
| 248 | * to Set Path Group ID was received. |
| 249 | */ |
| 250 | static int |
| 251 | __ccw_device_check_pgid(struct ccw_device *cdev) |
| 252 | { |
| 253 | struct subchannel *sch; |
| 254 | struct irb *irb; |
| 255 | |
| 256 | sch = to_subchannel(cdev->dev.parent); |
| 257 | irb = &cdev->private->irb; |
| 258 | if (irb->scsw.fctl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) |
| 259 | return -ETIME; |
| 260 | if (irb->esw.esw0.erw.cons) { |
| 261 | if (irb->ecw[0] & SNS0_CMD_REJECT) |
| 262 | return -EOPNOTSUPP; |
| 263 | /* Hmm, whatever happened, try again. */ |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 264 | CIO_MSG_EVENT(2, "SPID - device 0.%x.%04x, unit check, " |
| 265 | "cnt %02d, " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | "sns : %02X%02X%02X%02X %02X%02X%02X%02X ...\n", |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 267 | cdev->private->ssid, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | cdev->private->devno, irb->esw.esw0.erw.scnt, |
| 269 | irb->ecw[0], irb->ecw[1], |
| 270 | irb->ecw[2], irb->ecw[3], |
| 271 | irb->ecw[4], irb->ecw[5], |
| 272 | irb->ecw[6], irb->ecw[7]); |
| 273 | return -EAGAIN; |
| 274 | } |
| 275 | if (irb->scsw.cc == 3) { |
Cornelia Huck | fb6958a | 2006-01-06 00:19:25 -0800 | [diff] [blame] | 276 | CIO_MSG_EVENT(2, "SPID - Device %04x on Subchannel 0.%x.%04x," |
| 277 | " lpm %02X, became 'not operational'\n", |
| 278 | cdev->private->devno, sch->schid.ssid, |
| 279 | sch->schid.sch_no, cdev->private->imask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | return -EACCES; |
| 281 | } |
| 282 | return 0; |
| 283 | } |
| 284 | |
| 285 | static void |
| 286 | __ccw_device_verify_start(struct ccw_device *cdev) |
| 287 | { |
| 288 | struct subchannel *sch; |
| 289 | __u8 imask, func; |
| 290 | int ret; |
| 291 | |
| 292 | sch = to_subchannel(cdev->dev.parent); |
| 293 | while (sch->vpm != sch->lpm) { |
| 294 | /* Find first unequal bit in vpm vs. lpm */ |
| 295 | for (imask = 0x80; imask != 0; imask >>= 1) |
| 296 | if ((sch->vpm & imask) != (sch->lpm & imask)) |
| 297 | break; |
| 298 | cdev->private->imask = imask; |
| 299 | func = (sch->vpm & imask) ? |
| 300 | SPID_FUNC_RESIGN : SPID_FUNC_ESTABLISH; |
| 301 | ret = __ccw_device_do_pgid(cdev, func); |
| 302 | if (ret == 0 || ret == -EBUSY) |
| 303 | return; |
| 304 | cdev->private->iretry = 5; |
| 305 | } |
| 306 | ccw_device_verify_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV); |
| 307 | } |
| 308 | |
| 309 | /* |
| 310 | * Got interrupt for Set Path Group ID. |
| 311 | */ |
| 312 | void |
| 313 | ccw_device_verify_irq(struct ccw_device *cdev, enum dev_event dev_event) |
| 314 | { |
| 315 | struct subchannel *sch; |
| 316 | struct irb *irb; |
| 317 | int ret; |
| 318 | |
| 319 | irb = (struct irb *) __LC_IRB; |
| 320 | /* Retry set pgid for cc=1. */ |
| 321 | if (irb->scsw.stctl == |
| 322 | (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { |
| 323 | if (irb->scsw.cc == 1) |
| 324 | __ccw_device_verify_start(cdev); |
| 325 | return; |
| 326 | } |
| 327 | if (ccw_device_accumulate_and_sense(cdev, irb) != 0) |
| 328 | return; |
| 329 | sch = to_subchannel(cdev->dev.parent); |
| 330 | ret = __ccw_device_check_pgid(cdev); |
| 331 | memset(&cdev->private->irb, 0, sizeof(struct irb)); |
| 332 | switch (ret) { |
| 333 | /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */ |
| 334 | case 0: |
| 335 | /* Establish or Resign Path Group done. Update vpm. */ |
| 336 | if ((sch->lpm & cdev->private->imask) != 0) |
| 337 | sch->vpm |= cdev->private->imask; |
| 338 | else |
| 339 | sch->vpm &= ~cdev->private->imask; |
| 340 | cdev->private->iretry = 5; |
| 341 | __ccw_device_verify_start(cdev); |
| 342 | break; |
| 343 | case -EOPNOTSUPP: |
| 344 | /* |
| 345 | * One of those strange devices which claim to be able |
| 346 | * to do multipathing but not for Set Path Group ID. |
| 347 | */ |
| 348 | if (cdev->private->flags.pgid_single) { |
| 349 | ccw_device_verify_done(cdev, -EOPNOTSUPP); |
| 350 | break; |
| 351 | } |
| 352 | cdev->private->flags.pgid_single = 1; |
| 353 | /* fall through. */ |
| 354 | case -EAGAIN: /* Try again. */ |
| 355 | __ccw_device_verify_start(cdev); |
| 356 | break; |
| 357 | case -ETIME: /* Set path group id stopped by timeout. */ |
| 358 | ccw_device_verify_done(cdev, -ETIME); |
| 359 | break; |
| 360 | case -EACCES: /* channel is not operational. */ |
| 361 | sch->lpm &= ~cdev->private->imask; |
| 362 | sch->vpm &= ~cdev->private->imask; |
| 363 | cdev->private->iretry = 5; |
| 364 | __ccw_device_verify_start(cdev); |
| 365 | break; |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | void |
| 370 | ccw_device_verify_start(struct ccw_device *cdev) |
| 371 | { |
Cornelia Huck | 6810a2b | 2006-01-06 00:19:13 -0800 | [diff] [blame] | 372 | struct subchannel *sch = to_subchannel(cdev->dev.parent); |
| 373 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | cdev->private->flags.pgid_single = 0; |
| 375 | cdev->private->iretry = 5; |
Cornelia Huck | 6810a2b | 2006-01-06 00:19:13 -0800 | [diff] [blame] | 376 | /* |
| 377 | * Update sch->lpm with current values to catch paths becoming |
| 378 | * available again. |
| 379 | */ |
Cornelia Huck | a8237fc | 2006-01-06 00:19:21 -0800 | [diff] [blame] | 380 | if (stsch(sch->schid, &sch->schib)) { |
Cornelia Huck | 6810a2b | 2006-01-06 00:19:13 -0800 | [diff] [blame] | 381 | ccw_device_verify_done(cdev, -ENODEV); |
| 382 | return; |
| 383 | } |
| 384 | sch->lpm = sch->schib.pmcw.pim & |
| 385 | sch->schib.pmcw.pam & |
| 386 | sch->schib.pmcw.pom & |
| 387 | sch->opm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 388 | __ccw_device_verify_start(cdev); |
| 389 | } |
| 390 | |
| 391 | static void |
| 392 | __ccw_device_disband_start(struct ccw_device *cdev) |
| 393 | { |
| 394 | struct subchannel *sch; |
| 395 | int ret; |
| 396 | |
| 397 | sch = to_subchannel(cdev->dev.parent); |
| 398 | while (cdev->private->imask != 0) { |
| 399 | if (sch->lpm & cdev->private->imask) { |
| 400 | ret = __ccw_device_do_pgid(cdev, SPID_FUNC_DISBAND); |
| 401 | if (ret == 0) |
| 402 | return; |
| 403 | } |
| 404 | cdev->private->iretry = 5; |
| 405 | cdev->private->imask >>= 1; |
| 406 | } |
Cornelia Huck | 6d751c4 | 2006-02-17 13:52:45 -0800 | [diff] [blame] | 407 | ccw_device_disband_done(cdev, (sch->lpm != 0) ? 0 : -ENODEV); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | } |
| 409 | |
| 410 | /* |
| 411 | * Got interrupt for Unset Path Group ID. |
| 412 | */ |
| 413 | void |
| 414 | ccw_device_disband_irq(struct ccw_device *cdev, enum dev_event dev_event) |
| 415 | { |
| 416 | struct subchannel *sch; |
| 417 | struct irb *irb; |
| 418 | int ret; |
| 419 | |
| 420 | irb = (struct irb *) __LC_IRB; |
| 421 | /* Retry set pgid for cc=1. */ |
| 422 | if (irb->scsw.stctl == |
| 423 | (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { |
| 424 | if (irb->scsw.cc == 1) |
| 425 | __ccw_device_disband_start(cdev); |
| 426 | return; |
| 427 | } |
| 428 | if (ccw_device_accumulate_and_sense(cdev, irb) != 0) |
| 429 | return; |
| 430 | sch = to_subchannel(cdev->dev.parent); |
| 431 | ret = __ccw_device_check_pgid(cdev); |
| 432 | memset(&cdev->private->irb, 0, sizeof(struct irb)); |
| 433 | switch (ret) { |
| 434 | /* 0, -ETIME, -EAGAIN, -EOPNOTSUPP or -EACCES */ |
| 435 | case 0: /* disband successful. */ |
| 436 | sch->vpm = 0; |
| 437 | ccw_device_disband_done(cdev, ret); |
| 438 | break; |
| 439 | case -EOPNOTSUPP: |
| 440 | /* |
| 441 | * One of those strange devices which claim to be able |
| 442 | * to do multipathing but not for Unset Path Group ID. |
| 443 | */ |
| 444 | cdev->private->flags.pgid_single = 1; |
| 445 | /* fall through. */ |
| 446 | case -EAGAIN: /* Try again. */ |
| 447 | __ccw_device_disband_start(cdev); |
| 448 | break; |
| 449 | case -ETIME: /* Set path group id stopped by timeout. */ |
| 450 | ccw_device_disband_done(cdev, -ETIME); |
| 451 | break; |
| 452 | case -EACCES: /* channel is not operational. */ |
| 453 | cdev->private->imask >>= 1; |
| 454 | cdev->private->iretry = 5; |
| 455 | __ccw_device_disband_start(cdev); |
| 456 | break; |
| 457 | } |
| 458 | } |
| 459 | |
| 460 | void |
| 461 | ccw_device_disband_start(struct ccw_device *cdev) |
| 462 | { |
| 463 | cdev->private->flags.pgid_single = 0; |
| 464 | cdev->private->iretry = 5; |
| 465 | cdev->private->imask = 0x80; |
| 466 | __ccw_device_disband_start(cdev); |
| 467 | } |