1 /* sunvdc.c: Sun LDOM Virtual Disk Client. 2 * 3 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net> 4 */ 5 6 #include <linux/module.h> 7 #include <linux/kernel.h> 8 #include <linux/types.h> 9 #include <linux/blk-mq.h> 10 #include <linux/hdreg.h> 11 #include <linux/genhd.h> 12 #include <linux/cdrom.h> 13 #include <linux/slab.h> 14 #include <linux/spinlock.h> 15 #include <linux/completion.h> 16 #include <linux/delay.h> 17 #include <linux/init.h> 18 #include <linux/list.h> 19 #include <linux/scatterlist.h> 20 21 #include <asm/vio.h> 22 #include <asm/ldc.h> 23 24 #define DRV_MODULE_NAME "sunvdc" 25 #define PFX DRV_MODULE_NAME ": " 26 #define DRV_MODULE_VERSION "1.2" 27 #define DRV_MODULE_RELDATE "November 24, 2014" 28 29 static char version[] = 30 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n"; 31 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)"); 32 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver"); 33 MODULE_LICENSE("GPL"); 34 MODULE_VERSION(DRV_MODULE_VERSION); 35 36 #define VDC_TX_RING_SIZE 512 37 #define VDC_DEFAULT_BLK_SIZE 512 38 39 #define MAX_XFER_BLKS (128 * 1024) 40 #define MAX_XFER_SIZE (MAX_XFER_BLKS / VDC_DEFAULT_BLK_SIZE) 41 #define MAX_RING_COOKIES ((MAX_XFER_BLKS / PAGE_SIZE) + 2) 42 43 #define WAITING_FOR_LINK_UP 0x01 44 #define WAITING_FOR_TX_SPACE 0x02 45 #define WAITING_FOR_GEN_CMD 0x04 46 #define WAITING_FOR_ANY -1 47 48 #define VDC_MAX_RETRIES 10 49 50 static struct workqueue_struct *sunvdc_wq; 51 52 struct vdc_req_entry { 53 struct request *req; 54 }; 55 56 struct vdc_port { 57 struct vio_driver_state vio; 58 59 struct gendisk *disk; 60 61 struct vdc_completion *cmp; 62 63 u64 req_id; 64 u64 seq; 65 struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE]; 66 67 unsigned long ring_cookies; 68 69 u64 max_xfer_size; 70 u32 vdisk_block_size; 71 u32 drain; 72 73 u64 ldc_timeout; 74 struct delayed_work ldc_reset_timer_work; 75 struct work_struct ldc_reset_work; 76 77 /* The server fills these in for us in the disk attribute 78 * ACK packet. 79 */ 80 u64 operations; 81 u32 vdisk_size; 82 u8 vdisk_type; 83 u8 vdisk_mtype; 84 u32 vdisk_phys_blksz; 85 86 struct blk_mq_tag_set tag_set; 87 88 char disk_name[32]; 89 }; 90 91 static void vdc_ldc_reset(struct vdc_port *port); 92 static void vdc_ldc_reset_work(struct work_struct *work); 93 static void vdc_ldc_reset_timer_work(struct work_struct *work); 94 95 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio) 96 { 97 return container_of(vio, struct vdc_port, vio); 98 } 99 100 /* Ordered from largest major to lowest */ 101 static struct vio_version vdc_versions[] = { 102 { .major = 1, .minor = 2 }, 103 { .major = 1, .minor = 1 }, 104 { .major = 1, .minor = 0 }, 105 }; 106 107 static inline int vdc_version_supported(struct vdc_port *port, 108 u16 major, u16 minor) 109 { 110 return port->vio.ver.major == major && port->vio.ver.minor >= minor; 111 } 112 113 #define VDCBLK_NAME "vdisk" 114 static int vdc_major; 115 #define PARTITION_SHIFT 3 116 117 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr) 118 { 119 return vio_dring_avail(dr, VDC_TX_RING_SIZE); 120 } 121 122 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo) 123 { 124 struct gendisk *disk = bdev->bd_disk; 125 sector_t nsect = get_capacity(disk); 126 sector_t cylinders = nsect; 127 128 geo->heads = 0xff; 129 geo->sectors = 0x3f; 130 sector_div(cylinders, geo->heads * geo->sectors); 131 geo->cylinders = cylinders; 132 if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect) 133 geo->cylinders = 0xffff; 134 135 return 0; 136 } 137 138 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev 139 * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD. 140 * Needed to be able to install inside an ldom from an iso image. 141 */ 142 static int vdc_ioctl(struct block_device *bdev, fmode_t mode, 143 unsigned command, unsigned long argument) 144 { 145 int i; 146 struct gendisk *disk; 147 148 switch (command) { 149 case CDROMMULTISESSION: 150 pr_debug(PFX "Multisession CDs not supported\n"); 151 for (i = 0; i < sizeof(struct cdrom_multisession); i++) 152 if (put_user(0, (char __user *)(argument + i))) 153 return -EFAULT; 154 return 0; 155 156 case CDROM_GET_CAPABILITY: 157 disk = bdev->bd_disk; 158 159 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD)) 160 return 0; 161 return -EINVAL; 162 163 default: 164 pr_debug(PFX "ioctl %08x not supported\n", command); 165 return -EINVAL; 166 } 167 } 168 169 static const struct block_device_operations vdc_fops = { 170 .owner = THIS_MODULE, 171 .getgeo = vdc_getgeo, 172 .ioctl = vdc_ioctl, 173 }; 174 175 static void vdc_blk_queue_start(struct vdc_port *port) 176 { 177 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 178 179 /* restart blk queue when ring is half emptied. also called after 180 * handshake completes, so check for initial handshake before we've 181 * allocated a disk. 182 */ 183 if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50) 184 blk_mq_start_stopped_hw_queues(port->disk->queue, true); 185 } 186 187 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for) 188 { 189 if (vio->cmp && 190 (waiting_for == -1 || 191 vio->cmp->waiting_for == waiting_for)) { 192 vio->cmp->err = err; 193 complete(&vio->cmp->com); 194 vio->cmp = NULL; 195 } 196 } 197 198 static void vdc_handshake_complete(struct vio_driver_state *vio) 199 { 200 struct vdc_port *port = to_vdc_port(vio); 201 202 cancel_delayed_work(&port->ldc_reset_timer_work); 203 vdc_finish(vio, 0, WAITING_FOR_LINK_UP); 204 vdc_blk_queue_start(port); 205 } 206 207 static int vdc_handle_unknown(struct vdc_port *port, void *arg) 208 { 209 struct vio_msg_tag *pkt = arg; 210 211 printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n", 212 pkt->type, pkt->stype, pkt->stype_env, pkt->sid); 213 printk(KERN_ERR PFX "Resetting connection.\n"); 214 215 ldc_disconnect(port->vio.lp); 216 217 return -ECONNRESET; 218 } 219 220 static int vdc_send_attr(struct vio_driver_state *vio) 221 { 222 struct vdc_port *port = to_vdc_port(vio); 223 struct vio_disk_attr_info pkt; 224 225 memset(&pkt, 0, sizeof(pkt)); 226 227 pkt.tag.type = VIO_TYPE_CTRL; 228 pkt.tag.stype = VIO_SUBTYPE_INFO; 229 pkt.tag.stype_env = VIO_ATTR_INFO; 230 pkt.tag.sid = vio_send_sid(vio); 231 232 pkt.xfer_mode = VIO_DRING_MODE; 233 pkt.vdisk_block_size = port->vdisk_block_size; 234 pkt.max_xfer_size = port->max_xfer_size; 235 236 viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n", 237 pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size); 238 239 return vio_ldc_send(&port->vio, &pkt, sizeof(pkt)); 240 } 241 242 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg) 243 { 244 struct vdc_port *port = to_vdc_port(vio); 245 struct vio_disk_attr_info *pkt = arg; 246 247 viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] " 248 "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n", 249 pkt->tag.stype, pkt->operations, 250 pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype, 251 pkt->xfer_mode, pkt->vdisk_block_size, 252 pkt->max_xfer_size); 253 254 if (pkt->tag.stype == VIO_SUBTYPE_ACK) { 255 switch (pkt->vdisk_type) { 256 case VD_DISK_TYPE_DISK: 257 case VD_DISK_TYPE_SLICE: 258 break; 259 260 default: 261 printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n", 262 vio->name, pkt->vdisk_type); 263 return -ECONNRESET; 264 } 265 266 if (pkt->vdisk_block_size > port->vdisk_block_size) { 267 printk(KERN_ERR PFX "%s: BLOCK size increased " 268 "%u --> %u\n", 269 vio->name, 270 port->vdisk_block_size, pkt->vdisk_block_size); 271 return -ECONNRESET; 272 } 273 274 port->operations = pkt->operations; 275 port->vdisk_type = pkt->vdisk_type; 276 if (vdc_version_supported(port, 1, 1)) { 277 port->vdisk_size = pkt->vdisk_size; 278 port->vdisk_mtype = pkt->vdisk_mtype; 279 } 280 if (pkt->max_xfer_size < port->max_xfer_size) 281 port->max_xfer_size = pkt->max_xfer_size; 282 port->vdisk_block_size = pkt->vdisk_block_size; 283 284 port->vdisk_phys_blksz = VDC_DEFAULT_BLK_SIZE; 285 if (vdc_version_supported(port, 1, 2)) 286 port->vdisk_phys_blksz = pkt->phys_block_size; 287 288 return 0; 289 } else { 290 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name); 291 292 return -ECONNRESET; 293 } 294 } 295 296 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc) 297 { 298 int err = desc->status; 299 300 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD); 301 } 302 303 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr, 304 unsigned int index) 305 { 306 struct vio_disk_desc *desc = vio_dring_entry(dr, index); 307 struct vdc_req_entry *rqe = &port->rq_arr[index]; 308 struct request *req; 309 310 if (unlikely(desc->hdr.state != VIO_DESC_DONE)) 311 return; 312 313 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies); 314 desc->hdr.state = VIO_DESC_FREE; 315 dr->cons = vio_dring_next(dr, index); 316 317 req = rqe->req; 318 if (req == NULL) { 319 vdc_end_special(port, desc); 320 return; 321 } 322 323 rqe->req = NULL; 324 325 blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0); 326 327 vdc_blk_queue_start(port); 328 } 329 330 static int vdc_ack(struct vdc_port *port, void *msgbuf) 331 { 332 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 333 struct vio_dring_data *pkt = msgbuf; 334 335 if (unlikely(pkt->dring_ident != dr->ident || 336 pkt->start_idx != pkt->end_idx || 337 pkt->start_idx >= VDC_TX_RING_SIZE)) 338 return 0; 339 340 vdc_end_one(port, dr, pkt->start_idx); 341 342 return 0; 343 } 344 345 static int vdc_nack(struct vdc_port *port, void *msgbuf) 346 { 347 /* XXX Implement me XXX */ 348 return 0; 349 } 350 351 static void vdc_event(void *arg, int event) 352 { 353 struct vdc_port *port = arg; 354 struct vio_driver_state *vio = &port->vio; 355 unsigned long flags; 356 int err; 357 358 spin_lock_irqsave(&vio->lock, flags); 359 360 if (unlikely(event == LDC_EVENT_RESET)) { 361 vio_link_state_change(vio, event); 362 queue_work(sunvdc_wq, &port->ldc_reset_work); 363 goto out; 364 } 365 366 if (unlikely(event == LDC_EVENT_UP)) { 367 vio_link_state_change(vio, event); 368 goto out; 369 } 370 371 if (unlikely(event != LDC_EVENT_DATA_READY)) { 372 pr_warn(PFX "Unexpected LDC event %d\n", event); 373 goto out; 374 } 375 376 err = 0; 377 while (1) { 378 union { 379 struct vio_msg_tag tag; 380 u64 raw[8]; 381 } msgbuf; 382 383 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf)); 384 if (unlikely(err < 0)) { 385 if (err == -ECONNRESET) 386 vio_conn_reset(vio); 387 break; 388 } 389 if (err == 0) 390 break; 391 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n", 392 msgbuf.tag.type, 393 msgbuf.tag.stype, 394 msgbuf.tag.stype_env, 395 msgbuf.tag.sid); 396 err = vio_validate_sid(vio, &msgbuf.tag); 397 if (err < 0) 398 break; 399 400 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) { 401 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) 402 err = vdc_ack(port, &msgbuf); 403 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) 404 err = vdc_nack(port, &msgbuf); 405 else 406 err = vdc_handle_unknown(port, &msgbuf); 407 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) { 408 err = vio_control_pkt_engine(vio, &msgbuf); 409 } else { 410 err = vdc_handle_unknown(port, &msgbuf); 411 } 412 if (err < 0) 413 break; 414 } 415 if (err < 0) 416 vdc_finish(&port->vio, err, WAITING_FOR_ANY); 417 out: 418 spin_unlock_irqrestore(&vio->lock, flags); 419 } 420 421 static int __vdc_tx_trigger(struct vdc_port *port) 422 { 423 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 424 struct vio_dring_data hdr = { 425 .tag = { 426 .type = VIO_TYPE_DATA, 427 .stype = VIO_SUBTYPE_INFO, 428 .stype_env = VIO_DRING_DATA, 429 .sid = vio_send_sid(&port->vio), 430 }, 431 .dring_ident = dr->ident, 432 .start_idx = dr->prod, 433 .end_idx = dr->prod, 434 }; 435 int err, delay; 436 int retries = 0; 437 438 hdr.seq = dr->snd_nxt; 439 delay = 1; 440 do { 441 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr)); 442 if (err > 0) { 443 dr->snd_nxt++; 444 break; 445 } 446 udelay(delay); 447 if ((delay <<= 1) > 128) 448 delay = 128; 449 if (retries++ > VDC_MAX_RETRIES) 450 break; 451 } while (err == -EAGAIN); 452 453 if (err == -ENOTCONN) 454 vdc_ldc_reset(port); 455 return err; 456 } 457 458 static int __send_request(struct request *req) 459 { 460 struct vdc_port *port = req->rq_disk->private_data; 461 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 462 struct scatterlist sg[MAX_RING_COOKIES]; 463 struct vdc_req_entry *rqe; 464 struct vio_disk_desc *desc; 465 unsigned int map_perm; 466 int nsg, err, i; 467 u64 len; 468 u8 op; 469 470 if (WARN_ON(port->ring_cookies > MAX_RING_COOKIES)) 471 return -EINVAL; 472 473 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO; 474 475 if (rq_data_dir(req) == READ) { 476 map_perm |= LDC_MAP_W; 477 op = VD_OP_BREAD; 478 } else { 479 map_perm |= LDC_MAP_R; 480 op = VD_OP_BWRITE; 481 } 482 483 sg_init_table(sg, port->ring_cookies); 484 nsg = blk_rq_map_sg(req->q, req, sg); 485 486 len = 0; 487 for (i = 0; i < nsg; i++) 488 len += sg[i].length; 489 490 desc = vio_dring_cur(dr); 491 492 err = ldc_map_sg(port->vio.lp, sg, nsg, 493 desc->cookies, port->ring_cookies, 494 map_perm); 495 if (err < 0) { 496 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err); 497 return err; 498 } 499 500 rqe = &port->rq_arr[dr->prod]; 501 rqe->req = req; 502 503 desc->hdr.ack = VIO_ACK_ENABLE; 504 desc->req_id = port->req_id; 505 desc->operation = op; 506 if (port->vdisk_type == VD_DISK_TYPE_DISK) { 507 desc->slice = 0xff; 508 } else { 509 desc->slice = 0; 510 } 511 desc->status = ~0; 512 desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size; 513 desc->size = len; 514 desc->ncookies = err; 515 516 /* This has to be a non-SMP write barrier because we are writing 517 * to memory which is shared with the peer LDOM. 518 */ 519 wmb(); 520 desc->hdr.state = VIO_DESC_READY; 521 522 err = __vdc_tx_trigger(port); 523 if (err < 0) { 524 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err); 525 } else { 526 port->req_id++; 527 dr->prod = vio_dring_next(dr, dr->prod); 528 } 529 530 return err; 531 } 532 533 static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx, 534 const struct blk_mq_queue_data *bd) 535 { 536 struct vdc_port *port = hctx->queue->queuedata; 537 struct vio_dring_state *dr; 538 unsigned long flags; 539 540 dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 541 542 blk_mq_start_request(bd->rq); 543 544 spin_lock_irqsave(&port->vio.lock, flags); 545 546 /* 547 * Doing drain, just end the request in error 548 */ 549 if (unlikely(port->drain)) { 550 spin_unlock_irqrestore(&port->vio.lock, flags); 551 return BLK_STS_IOERR; 552 } 553 554 if (unlikely(vdc_tx_dring_avail(dr) < 1)) { 555 spin_unlock_irqrestore(&port->vio.lock, flags); 556 blk_mq_stop_hw_queue(hctx); 557 return BLK_STS_DEV_RESOURCE; 558 } 559 560 if (__send_request(bd->rq) < 0) { 561 spin_unlock_irqrestore(&port->vio.lock, flags); 562 return BLK_STS_IOERR; 563 } 564 565 spin_unlock_irqrestore(&port->vio.lock, flags); 566 return BLK_STS_OK; 567 } 568 569 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len) 570 { 571 struct vio_dring_state *dr; 572 struct vio_completion comp; 573 struct vio_disk_desc *desc; 574 unsigned int map_perm; 575 unsigned long flags; 576 int op_len, err; 577 void *req_buf; 578 579 if (!(((u64)1 << (u64)op) & port->operations)) 580 return -EOPNOTSUPP; 581 582 switch (op) { 583 case VD_OP_BREAD: 584 case VD_OP_BWRITE: 585 default: 586 return -EINVAL; 587 588 case VD_OP_FLUSH: 589 op_len = 0; 590 map_perm = 0; 591 break; 592 593 case VD_OP_GET_WCE: 594 op_len = sizeof(u32); 595 map_perm = LDC_MAP_W; 596 break; 597 598 case VD_OP_SET_WCE: 599 op_len = sizeof(u32); 600 map_perm = LDC_MAP_R; 601 break; 602 603 case VD_OP_GET_VTOC: 604 op_len = sizeof(struct vio_disk_vtoc); 605 map_perm = LDC_MAP_W; 606 break; 607 608 case VD_OP_SET_VTOC: 609 op_len = sizeof(struct vio_disk_vtoc); 610 map_perm = LDC_MAP_R; 611 break; 612 613 case VD_OP_GET_DISKGEOM: 614 op_len = sizeof(struct vio_disk_geom); 615 map_perm = LDC_MAP_W; 616 break; 617 618 case VD_OP_SET_DISKGEOM: 619 op_len = sizeof(struct vio_disk_geom); 620 map_perm = LDC_MAP_R; 621 break; 622 623 case VD_OP_SCSICMD: 624 op_len = 16; 625 map_perm = LDC_MAP_RW; 626 break; 627 628 case VD_OP_GET_DEVID: 629 op_len = sizeof(struct vio_disk_devid); 630 map_perm = LDC_MAP_W; 631 break; 632 633 case VD_OP_GET_EFI: 634 case VD_OP_SET_EFI: 635 return -EOPNOTSUPP; 636 }; 637 638 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO; 639 640 op_len = (op_len + 7) & ~7; 641 req_buf = kzalloc(op_len, GFP_KERNEL); 642 if (!req_buf) 643 return -ENOMEM; 644 645 if (len > op_len) 646 len = op_len; 647 648 if (map_perm & LDC_MAP_R) 649 memcpy(req_buf, buf, len); 650 651 spin_lock_irqsave(&port->vio.lock, flags); 652 653 dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 654 655 /* XXX If we want to use this code generically we have to 656 * XXX handle TX ring exhaustion etc. 657 */ 658 desc = vio_dring_cur(dr); 659 660 err = ldc_map_single(port->vio.lp, req_buf, op_len, 661 desc->cookies, port->ring_cookies, 662 map_perm); 663 if (err < 0) { 664 spin_unlock_irqrestore(&port->vio.lock, flags); 665 kfree(req_buf); 666 return err; 667 } 668 669 init_completion(&comp.com); 670 comp.waiting_for = WAITING_FOR_GEN_CMD; 671 port->vio.cmp = ∁ 672 673 desc->hdr.ack = VIO_ACK_ENABLE; 674 desc->req_id = port->req_id; 675 desc->operation = op; 676 desc->slice = 0; 677 desc->status = ~0; 678 desc->offset = 0; 679 desc->size = op_len; 680 desc->ncookies = err; 681 682 /* This has to be a non-SMP write barrier because we are writing 683 * to memory which is shared with the peer LDOM. 684 */ 685 wmb(); 686 desc->hdr.state = VIO_DESC_READY; 687 688 err = __vdc_tx_trigger(port); 689 if (err >= 0) { 690 port->req_id++; 691 dr->prod = vio_dring_next(dr, dr->prod); 692 spin_unlock_irqrestore(&port->vio.lock, flags); 693 694 wait_for_completion(&comp.com); 695 err = comp.err; 696 } else { 697 port->vio.cmp = NULL; 698 spin_unlock_irqrestore(&port->vio.lock, flags); 699 } 700 701 if (map_perm & LDC_MAP_W) 702 memcpy(buf, req_buf, len); 703 704 kfree(req_buf); 705 706 return err; 707 } 708 709 static int vdc_alloc_tx_ring(struct vdc_port *port) 710 { 711 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 712 unsigned long len, entry_size; 713 int ncookies; 714 void *dring; 715 716 entry_size = sizeof(struct vio_disk_desc) + 717 (sizeof(struct ldc_trans_cookie) * port->ring_cookies); 718 len = (VDC_TX_RING_SIZE * entry_size); 719 720 ncookies = VIO_MAX_RING_COOKIES; 721 dring = ldc_alloc_exp_dring(port->vio.lp, len, 722 dr->cookies, &ncookies, 723 (LDC_MAP_SHADOW | 724 LDC_MAP_DIRECT | 725 LDC_MAP_RW)); 726 if (IS_ERR(dring)) 727 return PTR_ERR(dring); 728 729 dr->base = dring; 730 dr->entry_size = entry_size; 731 dr->num_entries = VDC_TX_RING_SIZE; 732 dr->prod = dr->cons = 0; 733 dr->pending = VDC_TX_RING_SIZE; 734 dr->ncookies = ncookies; 735 736 return 0; 737 } 738 739 static void vdc_free_tx_ring(struct vdc_port *port) 740 { 741 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 742 743 if (dr->base) { 744 ldc_free_exp_dring(port->vio.lp, dr->base, 745 (dr->entry_size * dr->num_entries), 746 dr->cookies, dr->ncookies); 747 dr->base = NULL; 748 dr->entry_size = 0; 749 dr->num_entries = 0; 750 dr->pending = 0; 751 dr->ncookies = 0; 752 } 753 } 754 755 static int vdc_port_up(struct vdc_port *port) 756 { 757 struct vio_completion comp; 758 759 init_completion(&comp.com); 760 comp.err = 0; 761 comp.waiting_for = WAITING_FOR_LINK_UP; 762 port->vio.cmp = ∁ 763 764 vio_port_up(&port->vio); 765 wait_for_completion(&comp.com); 766 return comp.err; 767 } 768 769 static void vdc_port_down(struct vdc_port *port) 770 { 771 ldc_disconnect(port->vio.lp); 772 ldc_unbind(port->vio.lp); 773 vdc_free_tx_ring(port); 774 vio_ldc_free(&port->vio); 775 } 776 777 static const struct blk_mq_ops vdc_mq_ops = { 778 .queue_rq = vdc_queue_rq, 779 }; 780 781 static void cleanup_queue(struct request_queue *q) 782 { 783 struct vdc_port *port = q->queuedata; 784 785 blk_cleanup_queue(q); 786 blk_mq_free_tag_set(&port->tag_set); 787 } 788 789 static struct request_queue *init_queue(struct vdc_port *port) 790 { 791 struct request_queue *q; 792 793 q = blk_mq_init_sq_queue(&port->tag_set, &vdc_mq_ops, VDC_TX_RING_SIZE, 794 BLK_MQ_F_SHOULD_MERGE); 795 if (IS_ERR(q)) 796 return q; 797 798 q->queuedata = port; 799 return q; 800 } 801 802 static int probe_disk(struct vdc_port *port) 803 { 804 struct request_queue *q; 805 struct gendisk *g; 806 int err; 807 808 err = vdc_port_up(port); 809 if (err) 810 return err; 811 812 /* Using version 1.2 means vdisk_phys_blksz should be set unless the 813 * disk is reserved by another system. 814 */ 815 if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz) 816 return -ENODEV; 817 818 if (vdc_version_supported(port, 1, 1)) { 819 /* vdisk_size should be set during the handshake, if it wasn't 820 * then the underlying disk is reserved by another system 821 */ 822 if (port->vdisk_size == -1) 823 return -ENODEV; 824 } else { 825 struct vio_disk_geom geom; 826 827 err = generic_request(port, VD_OP_GET_DISKGEOM, 828 &geom, sizeof(geom)); 829 if (err < 0) { 830 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns " 831 "error %d\n", err); 832 return err; 833 } 834 port->vdisk_size = ((u64)geom.num_cyl * 835 (u64)geom.num_hd * 836 (u64)geom.num_sec); 837 } 838 839 q = init_queue(port); 840 if (IS_ERR(q)) { 841 printk(KERN_ERR PFX "%s: Could not allocate queue.\n", 842 port->vio.name); 843 return PTR_ERR(q); 844 } 845 g = alloc_disk(1 << PARTITION_SHIFT); 846 if (!g) { 847 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n", 848 port->vio.name); 849 cleanup_queue(q); 850 return -ENOMEM; 851 } 852 853 port->disk = g; 854 855 /* Each segment in a request is up to an aligned page in size. */ 856 blk_queue_segment_boundary(q, PAGE_SIZE - 1); 857 blk_queue_max_segment_size(q, PAGE_SIZE); 858 859 blk_queue_max_segments(q, port->ring_cookies); 860 blk_queue_max_hw_sectors(q, port->max_xfer_size); 861 g->major = vdc_major; 862 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT; 863 strcpy(g->disk_name, port->disk_name); 864 865 g->fops = &vdc_fops; 866 g->queue = q; 867 g->private_data = port; 868 869 set_capacity(g, port->vdisk_size); 870 871 if (vdc_version_supported(port, 1, 1)) { 872 switch (port->vdisk_mtype) { 873 case VD_MEDIA_TYPE_CD: 874 pr_info(PFX "Virtual CDROM %s\n", port->disk_name); 875 g->flags |= GENHD_FL_CD; 876 g->flags |= GENHD_FL_REMOVABLE; 877 set_disk_ro(g, 1); 878 break; 879 880 case VD_MEDIA_TYPE_DVD: 881 pr_info(PFX "Virtual DVD %s\n", port->disk_name); 882 g->flags |= GENHD_FL_CD; 883 g->flags |= GENHD_FL_REMOVABLE; 884 set_disk_ro(g, 1); 885 break; 886 887 case VD_MEDIA_TYPE_FIXED: 888 pr_info(PFX "Virtual Hard disk %s\n", port->disk_name); 889 break; 890 } 891 } 892 893 blk_queue_physical_block_size(q, port->vdisk_phys_blksz); 894 895 pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n", 896 g->disk_name, 897 port->vdisk_size, (port->vdisk_size >> (20 - 9)), 898 port->vio.ver.major, port->vio.ver.minor); 899 900 device_add_disk(&port->vio.vdev->dev, g, NULL); 901 902 return 0; 903 } 904 905 static struct ldc_channel_config vdc_ldc_cfg = { 906 .event = vdc_event, 907 .mtu = 64, 908 .mode = LDC_MODE_UNRELIABLE, 909 }; 910 911 static struct vio_driver_ops vdc_vio_ops = { 912 .send_attr = vdc_send_attr, 913 .handle_attr = vdc_handle_attr, 914 .handshake_complete = vdc_handshake_complete, 915 }; 916 917 static void print_version(void) 918 { 919 static int version_printed; 920 921 if (version_printed++ == 0) 922 printk(KERN_INFO "%s", version); 923 } 924 925 struct vdc_check_port_data { 926 int dev_no; 927 char *type; 928 }; 929 930 static int vdc_device_probed(struct device *dev, void *arg) 931 { 932 struct vio_dev *vdev = to_vio_dev(dev); 933 struct vdc_check_port_data *port_data; 934 935 port_data = (struct vdc_check_port_data *)arg; 936 937 if ((vdev->dev_no == port_data->dev_no) && 938 (!(strcmp((char *)&vdev->type, port_data->type))) && 939 dev_get_drvdata(dev)) { 940 /* This device has already been configured 941 * by vdc_port_probe() 942 */ 943 return 1; 944 } else { 945 return 0; 946 } 947 } 948 949 /* Determine whether the VIO device is part of an mpgroup 950 * by locating all the virtual-device-port nodes associated 951 * with the parent virtual-device node for the VIO device 952 * and checking whether any of these nodes are vdc-ports 953 * which have already been configured. 954 * 955 * Returns true if this device is part of an mpgroup and has 956 * already been probed. 957 */ 958 static bool vdc_port_mpgroup_check(struct vio_dev *vdev) 959 { 960 struct vdc_check_port_data port_data; 961 struct device *dev; 962 963 port_data.dev_no = vdev->dev_no; 964 port_data.type = (char *)&vdev->type; 965 966 dev = device_find_child(vdev->dev.parent, &port_data, 967 vdc_device_probed); 968 969 if (dev) 970 return true; 971 972 return false; 973 } 974 975 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id) 976 { 977 struct mdesc_handle *hp; 978 struct vdc_port *port; 979 int err; 980 const u64 *ldc_timeout; 981 982 print_version(); 983 984 hp = mdesc_grab(); 985 986 err = -ENODEV; 987 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) { 988 printk(KERN_ERR PFX "Port id [%llu] too large.\n", 989 vdev->dev_no); 990 goto err_out_release_mdesc; 991 } 992 993 /* Check if this device is part of an mpgroup */ 994 if (vdc_port_mpgroup_check(vdev)) { 995 printk(KERN_WARNING 996 "VIO: Ignoring extra vdisk port %s", 997 dev_name(&vdev->dev)); 998 goto err_out_release_mdesc; 999 } 1000 1001 port = kzalloc(sizeof(*port), GFP_KERNEL); 1002 err = -ENOMEM; 1003 if (!port) { 1004 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n"); 1005 goto err_out_release_mdesc; 1006 } 1007 1008 if (vdev->dev_no >= 26) 1009 snprintf(port->disk_name, sizeof(port->disk_name), 1010 VDCBLK_NAME "%c%c", 1011 'a' + ((int)vdev->dev_no / 26) - 1, 1012 'a' + ((int)vdev->dev_no % 26)); 1013 else 1014 snprintf(port->disk_name, sizeof(port->disk_name), 1015 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26)); 1016 port->vdisk_size = -1; 1017 1018 /* Actual wall time may be double due to do_generic_file_read() doing 1019 * a readahead I/O first, and once that fails it will try to read a 1020 * single page. 1021 */ 1022 ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL); 1023 port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0; 1024 INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work); 1025 INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work); 1026 1027 err = vio_driver_init(&port->vio, vdev, VDEV_DISK, 1028 vdc_versions, ARRAY_SIZE(vdc_versions), 1029 &vdc_vio_ops, port->disk_name); 1030 if (err) 1031 goto err_out_free_port; 1032 1033 port->vdisk_block_size = VDC_DEFAULT_BLK_SIZE; 1034 port->max_xfer_size = MAX_XFER_SIZE; 1035 port->ring_cookies = MAX_RING_COOKIES; 1036 1037 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port); 1038 if (err) 1039 goto err_out_free_port; 1040 1041 err = vdc_alloc_tx_ring(port); 1042 if (err) 1043 goto err_out_free_ldc; 1044 1045 err = probe_disk(port); 1046 if (err) 1047 goto err_out_free_tx_ring; 1048 1049 /* Note that the device driver_data is used to determine 1050 * whether the port has been probed. 1051 */ 1052 dev_set_drvdata(&vdev->dev, port); 1053 1054 mdesc_release(hp); 1055 1056 return 0; 1057 1058 err_out_free_tx_ring: 1059 vdc_free_tx_ring(port); 1060 1061 err_out_free_ldc: 1062 vio_ldc_free(&port->vio); 1063 1064 err_out_free_port: 1065 kfree(port); 1066 1067 err_out_release_mdesc: 1068 mdesc_release(hp); 1069 return err; 1070 } 1071 1072 static int vdc_port_remove(struct vio_dev *vdev) 1073 { 1074 struct vdc_port *port = dev_get_drvdata(&vdev->dev); 1075 1076 if (port) { 1077 blk_mq_stop_hw_queues(port->disk->queue); 1078 1079 flush_work(&port->ldc_reset_work); 1080 cancel_delayed_work_sync(&port->ldc_reset_timer_work); 1081 del_timer_sync(&port->vio.timer); 1082 1083 del_gendisk(port->disk); 1084 cleanup_queue(port->disk->queue); 1085 put_disk(port->disk); 1086 port->disk = NULL; 1087 1088 vdc_free_tx_ring(port); 1089 vio_ldc_free(&port->vio); 1090 1091 dev_set_drvdata(&vdev->dev, NULL); 1092 1093 kfree(port); 1094 } 1095 return 0; 1096 } 1097 1098 static void vdc_requeue_inflight(struct vdc_port *port) 1099 { 1100 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 1101 u32 idx; 1102 1103 for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) { 1104 struct vio_disk_desc *desc = vio_dring_entry(dr, idx); 1105 struct vdc_req_entry *rqe = &port->rq_arr[idx]; 1106 struct request *req; 1107 1108 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies); 1109 desc->hdr.state = VIO_DESC_FREE; 1110 dr->cons = vio_dring_next(dr, idx); 1111 1112 req = rqe->req; 1113 if (req == NULL) { 1114 vdc_end_special(port, desc); 1115 continue; 1116 } 1117 1118 rqe->req = NULL; 1119 blk_mq_requeue_request(req, false); 1120 } 1121 } 1122 1123 static void vdc_queue_drain(struct vdc_port *port) 1124 { 1125 struct request_queue *q = port->disk->queue; 1126 1127 /* 1128 * Mark the queue as draining, then freeze/quiesce to ensure 1129 * that all existing requests are seen in ->queue_rq() and killed 1130 */ 1131 port->drain = 1; 1132 spin_unlock_irq(&port->vio.lock); 1133 1134 blk_mq_freeze_queue(q); 1135 blk_mq_quiesce_queue(q); 1136 1137 spin_lock_irq(&port->vio.lock); 1138 port->drain = 0; 1139 blk_mq_unquiesce_queue(q); 1140 blk_mq_unfreeze_queue(q); 1141 } 1142 1143 static void vdc_ldc_reset_timer_work(struct work_struct *work) 1144 { 1145 struct vdc_port *port; 1146 struct vio_driver_state *vio; 1147 1148 port = container_of(work, struct vdc_port, ldc_reset_timer_work.work); 1149 vio = &port->vio; 1150 1151 spin_lock_irq(&vio->lock); 1152 if (!(port->vio.hs_state & VIO_HS_COMPLETE)) { 1153 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n", 1154 port->disk_name, port->ldc_timeout); 1155 vdc_queue_drain(port); 1156 vdc_blk_queue_start(port); 1157 } 1158 spin_unlock_irq(&vio->lock); 1159 } 1160 1161 static void vdc_ldc_reset_work(struct work_struct *work) 1162 { 1163 struct vdc_port *port; 1164 struct vio_driver_state *vio; 1165 unsigned long flags; 1166 1167 port = container_of(work, struct vdc_port, ldc_reset_work); 1168 vio = &port->vio; 1169 1170 spin_lock_irqsave(&vio->lock, flags); 1171 vdc_ldc_reset(port); 1172 spin_unlock_irqrestore(&vio->lock, flags); 1173 } 1174 1175 static void vdc_ldc_reset(struct vdc_port *port) 1176 { 1177 int err; 1178 1179 assert_spin_locked(&port->vio.lock); 1180 1181 pr_warn(PFX "%s ldc link reset\n", port->disk_name); 1182 blk_mq_stop_hw_queues(port->disk->queue); 1183 vdc_requeue_inflight(port); 1184 vdc_port_down(port); 1185 1186 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port); 1187 if (err) { 1188 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err); 1189 return; 1190 } 1191 1192 err = vdc_alloc_tx_ring(port); 1193 if (err) { 1194 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err); 1195 goto err_free_ldc; 1196 } 1197 1198 if (port->ldc_timeout) 1199 mod_delayed_work(system_wq, &port->ldc_reset_timer_work, 1200 round_jiffies(jiffies + HZ * port->ldc_timeout)); 1201 mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ)); 1202 return; 1203 1204 err_free_ldc: 1205 vio_ldc_free(&port->vio); 1206 } 1207 1208 static const struct vio_device_id vdc_port_match[] = { 1209 { 1210 .type = "vdc-port", 1211 }, 1212 {}, 1213 }; 1214 MODULE_DEVICE_TABLE(vio, vdc_port_match); 1215 1216 static struct vio_driver vdc_port_driver = { 1217 .id_table = vdc_port_match, 1218 .probe = vdc_port_probe, 1219 .remove = vdc_port_remove, 1220 .name = "vdc_port", 1221 }; 1222 1223 static int __init vdc_init(void) 1224 { 1225 int err; 1226 1227 sunvdc_wq = alloc_workqueue("sunvdc", 0, 0); 1228 if (!sunvdc_wq) 1229 return -ENOMEM; 1230 1231 err = register_blkdev(0, VDCBLK_NAME); 1232 if (err < 0) 1233 goto out_free_wq; 1234 1235 vdc_major = err; 1236 1237 err = vio_register_driver(&vdc_port_driver); 1238 if (err) 1239 goto out_unregister_blkdev; 1240 1241 return 0; 1242 1243 out_unregister_blkdev: 1244 unregister_blkdev(vdc_major, VDCBLK_NAME); 1245 vdc_major = 0; 1246 1247 out_free_wq: 1248 destroy_workqueue(sunvdc_wq); 1249 return err; 1250 } 1251 1252 static void __exit vdc_exit(void) 1253 { 1254 vio_unregister_driver(&vdc_port_driver); 1255 unregister_blkdev(vdc_major, VDCBLK_NAME); 1256 destroy_workqueue(sunvdc_wq); 1257 } 1258 1259 module_init(vdc_init); 1260 module_exit(vdc_exit); 1261