1 // SPDX-License-Identifier: GPL-2.0-only 2 /* sunvdc.c: Sun LDOM Virtual Disk Client. 3 * 4 * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net> 5 */ 6 7 #include <linux/module.h> 8 #include <linux/kernel.h> 9 #include <linux/types.h> 10 #include <linux/blk-mq.h> 11 #include <linux/hdreg.h> 12 #include <linux/genhd.h> 13 #include <linux/cdrom.h> 14 #include <linux/slab.h> 15 #include <linux/spinlock.h> 16 #include <linux/completion.h> 17 #include <linux/delay.h> 18 #include <linux/init.h> 19 #include <linux/list.h> 20 #include <linux/scatterlist.h> 21 22 #include <asm/vio.h> 23 #include <asm/ldc.h> 24 25 #define DRV_MODULE_NAME "sunvdc" 26 #define PFX DRV_MODULE_NAME ": " 27 #define DRV_MODULE_VERSION "1.2" 28 #define DRV_MODULE_RELDATE "November 24, 2014" 29 30 static char version[] = 31 DRV_MODULE_NAME ".c:v" DRV_MODULE_VERSION " (" DRV_MODULE_RELDATE ")\n"; 32 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)"); 33 MODULE_DESCRIPTION("Sun LDOM virtual disk client driver"); 34 MODULE_LICENSE("GPL"); 35 MODULE_VERSION(DRV_MODULE_VERSION); 36 37 #define VDC_TX_RING_SIZE 512 38 #define VDC_DEFAULT_BLK_SIZE 512 39 40 #define MAX_XFER_BLKS (128 * 1024) 41 #define MAX_XFER_SIZE (MAX_XFER_BLKS / VDC_DEFAULT_BLK_SIZE) 42 #define MAX_RING_COOKIES ((MAX_XFER_BLKS / PAGE_SIZE) + 2) 43 44 #define WAITING_FOR_LINK_UP 0x01 45 #define WAITING_FOR_TX_SPACE 0x02 46 #define WAITING_FOR_GEN_CMD 0x04 47 #define WAITING_FOR_ANY -1 48 49 #define VDC_MAX_RETRIES 10 50 51 static struct workqueue_struct *sunvdc_wq; 52 53 struct vdc_req_entry { 54 struct request *req; 55 }; 56 57 struct vdc_port { 58 struct vio_driver_state vio; 59 60 struct gendisk *disk; 61 62 struct vdc_completion *cmp; 63 64 u64 req_id; 65 u64 seq; 66 struct vdc_req_entry rq_arr[VDC_TX_RING_SIZE]; 67 68 unsigned long ring_cookies; 69 70 u64 max_xfer_size; 71 u32 vdisk_block_size; 72 u32 drain; 73 74 u64 ldc_timeout; 75 struct delayed_work ldc_reset_timer_work; 76 struct work_struct ldc_reset_work; 77 78 /* The server fills these in for us in the disk attribute 79 * ACK packet. 80 */ 81 u64 operations; 82 u32 vdisk_size; 83 u8 vdisk_type; 84 u8 vdisk_mtype; 85 u32 vdisk_phys_blksz; 86 87 struct blk_mq_tag_set tag_set; 88 89 char disk_name[32]; 90 }; 91 92 static void vdc_ldc_reset(struct vdc_port *port); 93 static void vdc_ldc_reset_work(struct work_struct *work); 94 static void vdc_ldc_reset_timer_work(struct work_struct *work); 95 96 static inline struct vdc_port *to_vdc_port(struct vio_driver_state *vio) 97 { 98 return container_of(vio, struct vdc_port, vio); 99 } 100 101 /* Ordered from largest major to lowest */ 102 static struct vio_version vdc_versions[] = { 103 { .major = 1, .minor = 2 }, 104 { .major = 1, .minor = 1 }, 105 { .major = 1, .minor = 0 }, 106 }; 107 108 static inline int vdc_version_supported(struct vdc_port *port, 109 u16 major, u16 minor) 110 { 111 return port->vio.ver.major == major && port->vio.ver.minor >= minor; 112 } 113 114 #define VDCBLK_NAME "vdisk" 115 static int vdc_major; 116 #define PARTITION_SHIFT 3 117 118 static inline u32 vdc_tx_dring_avail(struct vio_dring_state *dr) 119 { 120 return vio_dring_avail(dr, VDC_TX_RING_SIZE); 121 } 122 123 static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo) 124 { 125 struct gendisk *disk = bdev->bd_disk; 126 sector_t nsect = get_capacity(disk); 127 sector_t cylinders = nsect; 128 129 geo->heads = 0xff; 130 geo->sectors = 0x3f; 131 sector_div(cylinders, geo->heads * geo->sectors); 132 geo->cylinders = cylinders; 133 if ((sector_t)(geo->cylinders + 1) * geo->heads * geo->sectors < nsect) 134 geo->cylinders = 0xffff; 135 136 return 0; 137 } 138 139 /* Add ioctl/CDROM_GET_CAPABILITY to support cdrom_id in udev 140 * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD. 141 * Needed to be able to install inside an ldom from an iso image. 142 */ 143 static int vdc_ioctl(struct block_device *bdev, fmode_t mode, 144 unsigned command, unsigned long argument) 145 { 146 int i; 147 struct gendisk *disk; 148 149 switch (command) { 150 case CDROMMULTISESSION: 151 pr_debug(PFX "Multisession CDs not supported\n"); 152 for (i = 0; i < sizeof(struct cdrom_multisession); i++) 153 if (put_user(0, (char __user *)(argument + i))) 154 return -EFAULT; 155 return 0; 156 157 case CDROM_GET_CAPABILITY: 158 disk = bdev->bd_disk; 159 160 if (bdev->bd_disk && (disk->flags & GENHD_FL_CD)) 161 return 0; 162 return -EINVAL; 163 164 default: 165 pr_debug(PFX "ioctl %08x not supported\n", command); 166 return -EINVAL; 167 } 168 } 169 170 static const struct block_device_operations vdc_fops = { 171 .owner = THIS_MODULE, 172 .getgeo = vdc_getgeo, 173 .ioctl = vdc_ioctl, 174 }; 175 176 static void vdc_blk_queue_start(struct vdc_port *port) 177 { 178 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 179 180 /* restart blk queue when ring is half emptied. also called after 181 * handshake completes, so check for initial handshake before we've 182 * allocated a disk. 183 */ 184 if (port->disk && vdc_tx_dring_avail(dr) * 100 / VDC_TX_RING_SIZE >= 50) 185 blk_mq_start_stopped_hw_queues(port->disk->queue, true); 186 } 187 188 static void vdc_finish(struct vio_driver_state *vio, int err, int waiting_for) 189 { 190 if (vio->cmp && 191 (waiting_for == -1 || 192 vio->cmp->waiting_for == waiting_for)) { 193 vio->cmp->err = err; 194 complete(&vio->cmp->com); 195 vio->cmp = NULL; 196 } 197 } 198 199 static void vdc_handshake_complete(struct vio_driver_state *vio) 200 { 201 struct vdc_port *port = to_vdc_port(vio); 202 203 cancel_delayed_work(&port->ldc_reset_timer_work); 204 vdc_finish(vio, 0, WAITING_FOR_LINK_UP); 205 vdc_blk_queue_start(port); 206 } 207 208 static int vdc_handle_unknown(struct vdc_port *port, void *arg) 209 { 210 struct vio_msg_tag *pkt = arg; 211 212 printk(KERN_ERR PFX "Received unknown msg [%02x:%02x:%04x:%08x]\n", 213 pkt->type, pkt->stype, pkt->stype_env, pkt->sid); 214 printk(KERN_ERR PFX "Resetting connection.\n"); 215 216 ldc_disconnect(port->vio.lp); 217 218 return -ECONNRESET; 219 } 220 221 static int vdc_send_attr(struct vio_driver_state *vio) 222 { 223 struct vdc_port *port = to_vdc_port(vio); 224 struct vio_disk_attr_info pkt; 225 226 memset(&pkt, 0, sizeof(pkt)); 227 228 pkt.tag.type = VIO_TYPE_CTRL; 229 pkt.tag.stype = VIO_SUBTYPE_INFO; 230 pkt.tag.stype_env = VIO_ATTR_INFO; 231 pkt.tag.sid = vio_send_sid(vio); 232 233 pkt.xfer_mode = VIO_DRING_MODE; 234 pkt.vdisk_block_size = port->vdisk_block_size; 235 pkt.max_xfer_size = port->max_xfer_size; 236 237 viodbg(HS, "SEND ATTR xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n", 238 pkt.xfer_mode, pkt.vdisk_block_size, pkt.max_xfer_size); 239 240 return vio_ldc_send(&port->vio, &pkt, sizeof(pkt)); 241 } 242 243 static int vdc_handle_attr(struct vio_driver_state *vio, void *arg) 244 { 245 struct vdc_port *port = to_vdc_port(vio); 246 struct vio_disk_attr_info *pkt = arg; 247 248 viodbg(HS, "GOT ATTR stype[0x%x] ops[%llx] disk_size[%llu] disk_type[%x] " 249 "mtype[0x%x] xfer_mode[0x%x] blksz[%u] max_xfer[%llu]\n", 250 pkt->tag.stype, pkt->operations, 251 pkt->vdisk_size, pkt->vdisk_type, pkt->vdisk_mtype, 252 pkt->xfer_mode, pkt->vdisk_block_size, 253 pkt->max_xfer_size); 254 255 if (pkt->tag.stype == VIO_SUBTYPE_ACK) { 256 switch (pkt->vdisk_type) { 257 case VD_DISK_TYPE_DISK: 258 case VD_DISK_TYPE_SLICE: 259 break; 260 261 default: 262 printk(KERN_ERR PFX "%s: Bogus vdisk_type 0x%x\n", 263 vio->name, pkt->vdisk_type); 264 return -ECONNRESET; 265 } 266 267 if (pkt->vdisk_block_size > port->vdisk_block_size) { 268 printk(KERN_ERR PFX "%s: BLOCK size increased " 269 "%u --> %u\n", 270 vio->name, 271 port->vdisk_block_size, pkt->vdisk_block_size); 272 return -ECONNRESET; 273 } 274 275 port->operations = pkt->operations; 276 port->vdisk_type = pkt->vdisk_type; 277 if (vdc_version_supported(port, 1, 1)) { 278 port->vdisk_size = pkt->vdisk_size; 279 port->vdisk_mtype = pkt->vdisk_mtype; 280 } 281 if (pkt->max_xfer_size < port->max_xfer_size) 282 port->max_xfer_size = pkt->max_xfer_size; 283 port->vdisk_block_size = pkt->vdisk_block_size; 284 285 port->vdisk_phys_blksz = VDC_DEFAULT_BLK_SIZE; 286 if (vdc_version_supported(port, 1, 2)) 287 port->vdisk_phys_blksz = pkt->phys_block_size; 288 289 return 0; 290 } else { 291 printk(KERN_ERR PFX "%s: Attribute NACK\n", vio->name); 292 293 return -ECONNRESET; 294 } 295 } 296 297 static void vdc_end_special(struct vdc_port *port, struct vio_disk_desc *desc) 298 { 299 int err = desc->status; 300 301 vdc_finish(&port->vio, -err, WAITING_FOR_GEN_CMD); 302 } 303 304 static void vdc_end_one(struct vdc_port *port, struct vio_dring_state *dr, 305 unsigned int index) 306 { 307 struct vio_disk_desc *desc = vio_dring_entry(dr, index); 308 struct vdc_req_entry *rqe = &port->rq_arr[index]; 309 struct request *req; 310 311 if (unlikely(desc->hdr.state != VIO_DESC_DONE)) 312 return; 313 314 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies); 315 desc->hdr.state = VIO_DESC_FREE; 316 dr->cons = vio_dring_next(dr, index); 317 318 req = rqe->req; 319 if (req == NULL) { 320 vdc_end_special(port, desc); 321 return; 322 } 323 324 rqe->req = NULL; 325 326 blk_mq_end_request(req, desc->status ? BLK_STS_IOERR : 0); 327 328 vdc_blk_queue_start(port); 329 } 330 331 static int vdc_ack(struct vdc_port *port, void *msgbuf) 332 { 333 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 334 struct vio_dring_data *pkt = msgbuf; 335 336 if (unlikely(pkt->dring_ident != dr->ident || 337 pkt->start_idx != pkt->end_idx || 338 pkt->start_idx >= VDC_TX_RING_SIZE)) 339 return 0; 340 341 vdc_end_one(port, dr, pkt->start_idx); 342 343 return 0; 344 } 345 346 static int vdc_nack(struct vdc_port *port, void *msgbuf) 347 { 348 /* XXX Implement me XXX */ 349 return 0; 350 } 351 352 static void vdc_event(void *arg, int event) 353 { 354 struct vdc_port *port = arg; 355 struct vio_driver_state *vio = &port->vio; 356 unsigned long flags; 357 int err; 358 359 spin_lock_irqsave(&vio->lock, flags); 360 361 if (unlikely(event == LDC_EVENT_RESET)) { 362 vio_link_state_change(vio, event); 363 queue_work(sunvdc_wq, &port->ldc_reset_work); 364 goto out; 365 } 366 367 if (unlikely(event == LDC_EVENT_UP)) { 368 vio_link_state_change(vio, event); 369 goto out; 370 } 371 372 if (unlikely(event != LDC_EVENT_DATA_READY)) { 373 pr_warn(PFX "Unexpected LDC event %d\n", event); 374 goto out; 375 } 376 377 err = 0; 378 while (1) { 379 union { 380 struct vio_msg_tag tag; 381 u64 raw[8]; 382 } msgbuf; 383 384 err = ldc_read(vio->lp, &msgbuf, sizeof(msgbuf)); 385 if (unlikely(err < 0)) { 386 if (err == -ECONNRESET) 387 vio_conn_reset(vio); 388 break; 389 } 390 if (err == 0) 391 break; 392 viodbg(DATA, "TAG [%02x:%02x:%04x:%08x]\n", 393 msgbuf.tag.type, 394 msgbuf.tag.stype, 395 msgbuf.tag.stype_env, 396 msgbuf.tag.sid); 397 err = vio_validate_sid(vio, &msgbuf.tag); 398 if (err < 0) 399 break; 400 401 if (likely(msgbuf.tag.type == VIO_TYPE_DATA)) { 402 if (msgbuf.tag.stype == VIO_SUBTYPE_ACK) 403 err = vdc_ack(port, &msgbuf); 404 else if (msgbuf.tag.stype == VIO_SUBTYPE_NACK) 405 err = vdc_nack(port, &msgbuf); 406 else 407 err = vdc_handle_unknown(port, &msgbuf); 408 } else if (msgbuf.tag.type == VIO_TYPE_CTRL) { 409 err = vio_control_pkt_engine(vio, &msgbuf); 410 } else { 411 err = vdc_handle_unknown(port, &msgbuf); 412 } 413 if (err < 0) 414 break; 415 } 416 if (err < 0) 417 vdc_finish(&port->vio, err, WAITING_FOR_ANY); 418 out: 419 spin_unlock_irqrestore(&vio->lock, flags); 420 } 421 422 static int __vdc_tx_trigger(struct vdc_port *port) 423 { 424 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 425 struct vio_dring_data hdr = { 426 .tag = { 427 .type = VIO_TYPE_DATA, 428 .stype = VIO_SUBTYPE_INFO, 429 .stype_env = VIO_DRING_DATA, 430 .sid = vio_send_sid(&port->vio), 431 }, 432 .dring_ident = dr->ident, 433 .start_idx = dr->prod, 434 .end_idx = dr->prod, 435 }; 436 int err, delay; 437 int retries = 0; 438 439 hdr.seq = dr->snd_nxt; 440 delay = 1; 441 do { 442 err = vio_ldc_send(&port->vio, &hdr, sizeof(hdr)); 443 if (err > 0) { 444 dr->snd_nxt++; 445 break; 446 } 447 udelay(delay); 448 if ((delay <<= 1) > 128) 449 delay = 128; 450 if (retries++ > VDC_MAX_RETRIES) 451 break; 452 } while (err == -EAGAIN); 453 454 if (err == -ENOTCONN) 455 vdc_ldc_reset(port); 456 return err; 457 } 458 459 static int __send_request(struct request *req) 460 { 461 struct vdc_port *port = req->rq_disk->private_data; 462 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 463 struct scatterlist sg[MAX_RING_COOKIES]; 464 struct vdc_req_entry *rqe; 465 struct vio_disk_desc *desc; 466 unsigned int map_perm; 467 int nsg, err, i; 468 u64 len; 469 u8 op; 470 471 if (WARN_ON(port->ring_cookies > MAX_RING_COOKIES)) 472 return -EINVAL; 473 474 map_perm = LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO; 475 476 if (rq_data_dir(req) == READ) { 477 map_perm |= LDC_MAP_W; 478 op = VD_OP_BREAD; 479 } else { 480 map_perm |= LDC_MAP_R; 481 op = VD_OP_BWRITE; 482 } 483 484 sg_init_table(sg, port->ring_cookies); 485 nsg = blk_rq_map_sg(req->q, req, sg); 486 487 len = 0; 488 for (i = 0; i < nsg; i++) 489 len += sg[i].length; 490 491 desc = vio_dring_cur(dr); 492 493 err = ldc_map_sg(port->vio.lp, sg, nsg, 494 desc->cookies, port->ring_cookies, 495 map_perm); 496 if (err < 0) { 497 printk(KERN_ERR PFX "ldc_map_sg() failure, err=%d.\n", err); 498 return err; 499 } 500 501 rqe = &port->rq_arr[dr->prod]; 502 rqe->req = req; 503 504 desc->hdr.ack = VIO_ACK_ENABLE; 505 desc->req_id = port->req_id; 506 desc->operation = op; 507 if (port->vdisk_type == VD_DISK_TYPE_DISK) { 508 desc->slice = 0xff; 509 } else { 510 desc->slice = 0; 511 } 512 desc->status = ~0; 513 desc->offset = (blk_rq_pos(req) << 9) / port->vdisk_block_size; 514 desc->size = len; 515 desc->ncookies = err; 516 517 /* This has to be a non-SMP write barrier because we are writing 518 * to memory which is shared with the peer LDOM. 519 */ 520 wmb(); 521 desc->hdr.state = VIO_DESC_READY; 522 523 err = __vdc_tx_trigger(port); 524 if (err < 0) { 525 printk(KERN_ERR PFX "vdc_tx_trigger() failure, err=%d\n", err); 526 } else { 527 port->req_id++; 528 dr->prod = vio_dring_next(dr, dr->prod); 529 } 530 531 return err; 532 } 533 534 static blk_status_t vdc_queue_rq(struct blk_mq_hw_ctx *hctx, 535 const struct blk_mq_queue_data *bd) 536 { 537 struct vdc_port *port = hctx->queue->queuedata; 538 struct vio_dring_state *dr; 539 unsigned long flags; 540 541 dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 542 543 blk_mq_start_request(bd->rq); 544 545 spin_lock_irqsave(&port->vio.lock, flags); 546 547 /* 548 * Doing drain, just end the request in error 549 */ 550 if (unlikely(port->drain)) { 551 spin_unlock_irqrestore(&port->vio.lock, flags); 552 return BLK_STS_IOERR; 553 } 554 555 if (unlikely(vdc_tx_dring_avail(dr) < 1)) { 556 spin_unlock_irqrestore(&port->vio.lock, flags); 557 blk_mq_stop_hw_queue(hctx); 558 return BLK_STS_DEV_RESOURCE; 559 } 560 561 if (__send_request(bd->rq) < 0) { 562 spin_unlock_irqrestore(&port->vio.lock, flags); 563 return BLK_STS_IOERR; 564 } 565 566 spin_unlock_irqrestore(&port->vio.lock, flags); 567 return BLK_STS_OK; 568 } 569 570 static int generic_request(struct vdc_port *port, u8 op, void *buf, int len) 571 { 572 struct vio_dring_state *dr; 573 struct vio_completion comp; 574 struct vio_disk_desc *desc; 575 unsigned int map_perm; 576 unsigned long flags; 577 int op_len, err; 578 void *req_buf; 579 580 if (!(((u64)1 << (u64)op) & port->operations)) 581 return -EOPNOTSUPP; 582 583 switch (op) { 584 case VD_OP_BREAD: 585 case VD_OP_BWRITE: 586 default: 587 return -EINVAL; 588 589 case VD_OP_FLUSH: 590 op_len = 0; 591 map_perm = 0; 592 break; 593 594 case VD_OP_GET_WCE: 595 op_len = sizeof(u32); 596 map_perm = LDC_MAP_W; 597 break; 598 599 case VD_OP_SET_WCE: 600 op_len = sizeof(u32); 601 map_perm = LDC_MAP_R; 602 break; 603 604 case VD_OP_GET_VTOC: 605 op_len = sizeof(struct vio_disk_vtoc); 606 map_perm = LDC_MAP_W; 607 break; 608 609 case VD_OP_SET_VTOC: 610 op_len = sizeof(struct vio_disk_vtoc); 611 map_perm = LDC_MAP_R; 612 break; 613 614 case VD_OP_GET_DISKGEOM: 615 op_len = sizeof(struct vio_disk_geom); 616 map_perm = LDC_MAP_W; 617 break; 618 619 case VD_OP_SET_DISKGEOM: 620 op_len = sizeof(struct vio_disk_geom); 621 map_perm = LDC_MAP_R; 622 break; 623 624 case VD_OP_SCSICMD: 625 op_len = 16; 626 map_perm = LDC_MAP_RW; 627 break; 628 629 case VD_OP_GET_DEVID: 630 op_len = sizeof(struct vio_disk_devid); 631 map_perm = LDC_MAP_W; 632 break; 633 634 case VD_OP_GET_EFI: 635 case VD_OP_SET_EFI: 636 return -EOPNOTSUPP; 637 } 638 639 map_perm |= LDC_MAP_SHADOW | LDC_MAP_DIRECT | LDC_MAP_IO; 640 641 op_len = (op_len + 7) & ~7; 642 req_buf = kzalloc(op_len, GFP_KERNEL); 643 if (!req_buf) 644 return -ENOMEM; 645 646 if (len > op_len) 647 len = op_len; 648 649 if (map_perm & LDC_MAP_R) 650 memcpy(req_buf, buf, len); 651 652 spin_lock_irqsave(&port->vio.lock, flags); 653 654 dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 655 656 /* XXX If we want to use this code generically we have to 657 * XXX handle TX ring exhaustion etc. 658 */ 659 desc = vio_dring_cur(dr); 660 661 err = ldc_map_single(port->vio.lp, req_buf, op_len, 662 desc->cookies, port->ring_cookies, 663 map_perm); 664 if (err < 0) { 665 spin_unlock_irqrestore(&port->vio.lock, flags); 666 kfree(req_buf); 667 return err; 668 } 669 670 init_completion(&comp.com); 671 comp.waiting_for = WAITING_FOR_GEN_CMD; 672 port->vio.cmp = ∁ 673 674 desc->hdr.ack = VIO_ACK_ENABLE; 675 desc->req_id = port->req_id; 676 desc->operation = op; 677 desc->slice = 0; 678 desc->status = ~0; 679 desc->offset = 0; 680 desc->size = op_len; 681 desc->ncookies = err; 682 683 /* This has to be a non-SMP write barrier because we are writing 684 * to memory which is shared with the peer LDOM. 685 */ 686 wmb(); 687 desc->hdr.state = VIO_DESC_READY; 688 689 err = __vdc_tx_trigger(port); 690 if (err >= 0) { 691 port->req_id++; 692 dr->prod = vio_dring_next(dr, dr->prod); 693 spin_unlock_irqrestore(&port->vio.lock, flags); 694 695 wait_for_completion(&comp.com); 696 err = comp.err; 697 } else { 698 port->vio.cmp = NULL; 699 spin_unlock_irqrestore(&port->vio.lock, flags); 700 } 701 702 if (map_perm & LDC_MAP_W) 703 memcpy(buf, req_buf, len); 704 705 kfree(req_buf); 706 707 return err; 708 } 709 710 static int vdc_alloc_tx_ring(struct vdc_port *port) 711 { 712 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 713 unsigned long len, entry_size; 714 int ncookies; 715 void *dring; 716 717 entry_size = sizeof(struct vio_disk_desc) + 718 (sizeof(struct ldc_trans_cookie) * port->ring_cookies); 719 len = (VDC_TX_RING_SIZE * entry_size); 720 721 ncookies = VIO_MAX_RING_COOKIES; 722 dring = ldc_alloc_exp_dring(port->vio.lp, len, 723 dr->cookies, &ncookies, 724 (LDC_MAP_SHADOW | 725 LDC_MAP_DIRECT | 726 LDC_MAP_RW)); 727 if (IS_ERR(dring)) 728 return PTR_ERR(dring); 729 730 dr->base = dring; 731 dr->entry_size = entry_size; 732 dr->num_entries = VDC_TX_RING_SIZE; 733 dr->prod = dr->cons = 0; 734 dr->pending = VDC_TX_RING_SIZE; 735 dr->ncookies = ncookies; 736 737 return 0; 738 } 739 740 static void vdc_free_tx_ring(struct vdc_port *port) 741 { 742 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 743 744 if (dr->base) { 745 ldc_free_exp_dring(port->vio.lp, dr->base, 746 (dr->entry_size * dr->num_entries), 747 dr->cookies, dr->ncookies); 748 dr->base = NULL; 749 dr->entry_size = 0; 750 dr->num_entries = 0; 751 dr->pending = 0; 752 dr->ncookies = 0; 753 } 754 } 755 756 static int vdc_port_up(struct vdc_port *port) 757 { 758 struct vio_completion comp; 759 760 init_completion(&comp.com); 761 comp.err = 0; 762 comp.waiting_for = WAITING_FOR_LINK_UP; 763 port->vio.cmp = ∁ 764 765 vio_port_up(&port->vio); 766 wait_for_completion(&comp.com); 767 return comp.err; 768 } 769 770 static void vdc_port_down(struct vdc_port *port) 771 { 772 ldc_disconnect(port->vio.lp); 773 ldc_unbind(port->vio.lp); 774 vdc_free_tx_ring(port); 775 vio_ldc_free(&port->vio); 776 } 777 778 static const struct blk_mq_ops vdc_mq_ops = { 779 .queue_rq = vdc_queue_rq, 780 }; 781 782 static void cleanup_queue(struct request_queue *q) 783 { 784 struct vdc_port *port = q->queuedata; 785 786 blk_cleanup_queue(q); 787 blk_mq_free_tag_set(&port->tag_set); 788 } 789 790 static struct request_queue *init_queue(struct vdc_port *port) 791 { 792 struct request_queue *q; 793 794 q = blk_mq_init_sq_queue(&port->tag_set, &vdc_mq_ops, VDC_TX_RING_SIZE, 795 BLK_MQ_F_SHOULD_MERGE); 796 if (IS_ERR(q)) 797 return q; 798 799 q->queuedata = port; 800 return q; 801 } 802 803 static int probe_disk(struct vdc_port *port) 804 { 805 struct request_queue *q; 806 struct gendisk *g; 807 int err; 808 809 err = vdc_port_up(port); 810 if (err) 811 return err; 812 813 /* Using version 1.2 means vdisk_phys_blksz should be set unless the 814 * disk is reserved by another system. 815 */ 816 if (vdc_version_supported(port, 1, 2) && !port->vdisk_phys_blksz) 817 return -ENODEV; 818 819 if (vdc_version_supported(port, 1, 1)) { 820 /* vdisk_size should be set during the handshake, if it wasn't 821 * then the underlying disk is reserved by another system 822 */ 823 if (port->vdisk_size == -1) 824 return -ENODEV; 825 } else { 826 struct vio_disk_geom geom; 827 828 err = generic_request(port, VD_OP_GET_DISKGEOM, 829 &geom, sizeof(geom)); 830 if (err < 0) { 831 printk(KERN_ERR PFX "VD_OP_GET_DISKGEOM returns " 832 "error %d\n", err); 833 return err; 834 } 835 port->vdisk_size = ((u64)geom.num_cyl * 836 (u64)geom.num_hd * 837 (u64)geom.num_sec); 838 } 839 840 q = init_queue(port); 841 if (IS_ERR(q)) { 842 printk(KERN_ERR PFX "%s: Could not allocate queue.\n", 843 port->vio.name); 844 return PTR_ERR(q); 845 } 846 g = alloc_disk(1 << PARTITION_SHIFT); 847 if (!g) { 848 printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n", 849 port->vio.name); 850 cleanup_queue(q); 851 return -ENOMEM; 852 } 853 854 port->disk = g; 855 856 /* Each segment in a request is up to an aligned page in size. */ 857 blk_queue_segment_boundary(q, PAGE_SIZE - 1); 858 blk_queue_max_segment_size(q, PAGE_SIZE); 859 860 blk_queue_max_segments(q, port->ring_cookies); 861 blk_queue_max_hw_sectors(q, port->max_xfer_size); 862 g->major = vdc_major; 863 g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT; 864 strcpy(g->disk_name, port->disk_name); 865 866 g->fops = &vdc_fops; 867 g->queue = q; 868 g->private_data = port; 869 870 set_capacity(g, port->vdisk_size); 871 872 if (vdc_version_supported(port, 1, 1)) { 873 switch (port->vdisk_mtype) { 874 case VD_MEDIA_TYPE_CD: 875 pr_info(PFX "Virtual CDROM %s\n", port->disk_name); 876 g->flags |= GENHD_FL_CD; 877 g->flags |= GENHD_FL_REMOVABLE; 878 set_disk_ro(g, 1); 879 break; 880 881 case VD_MEDIA_TYPE_DVD: 882 pr_info(PFX "Virtual DVD %s\n", port->disk_name); 883 g->flags |= GENHD_FL_CD; 884 g->flags |= GENHD_FL_REMOVABLE; 885 set_disk_ro(g, 1); 886 break; 887 888 case VD_MEDIA_TYPE_FIXED: 889 pr_info(PFX "Virtual Hard disk %s\n", port->disk_name); 890 break; 891 } 892 } 893 894 blk_queue_physical_block_size(q, port->vdisk_phys_blksz); 895 896 pr_info(PFX "%s: %u sectors (%u MB) protocol %d.%d\n", 897 g->disk_name, 898 port->vdisk_size, (port->vdisk_size >> (20 - 9)), 899 port->vio.ver.major, port->vio.ver.minor); 900 901 device_add_disk(&port->vio.vdev->dev, g, NULL); 902 903 return 0; 904 } 905 906 static struct ldc_channel_config vdc_ldc_cfg = { 907 .event = vdc_event, 908 .mtu = 64, 909 .mode = LDC_MODE_UNRELIABLE, 910 }; 911 912 static struct vio_driver_ops vdc_vio_ops = { 913 .send_attr = vdc_send_attr, 914 .handle_attr = vdc_handle_attr, 915 .handshake_complete = vdc_handshake_complete, 916 }; 917 918 static void print_version(void) 919 { 920 static int version_printed; 921 922 if (version_printed++ == 0) 923 printk(KERN_INFO "%s", version); 924 } 925 926 struct vdc_check_port_data { 927 int dev_no; 928 char *type; 929 }; 930 931 static int vdc_device_probed(struct device *dev, void *arg) 932 { 933 struct vio_dev *vdev = to_vio_dev(dev); 934 struct vdc_check_port_data *port_data; 935 936 port_data = (struct vdc_check_port_data *)arg; 937 938 if ((vdev->dev_no == port_data->dev_no) && 939 (!(strcmp((char *)&vdev->type, port_data->type))) && 940 dev_get_drvdata(dev)) { 941 /* This device has already been configured 942 * by vdc_port_probe() 943 */ 944 return 1; 945 } else { 946 return 0; 947 } 948 } 949 950 /* Determine whether the VIO device is part of an mpgroup 951 * by locating all the virtual-device-port nodes associated 952 * with the parent virtual-device node for the VIO device 953 * and checking whether any of these nodes are vdc-ports 954 * which have already been configured. 955 * 956 * Returns true if this device is part of an mpgroup and has 957 * already been probed. 958 */ 959 static bool vdc_port_mpgroup_check(struct vio_dev *vdev) 960 { 961 struct vdc_check_port_data port_data; 962 struct device *dev; 963 964 port_data.dev_no = vdev->dev_no; 965 port_data.type = (char *)&vdev->type; 966 967 dev = device_find_child(vdev->dev.parent, &port_data, 968 vdc_device_probed); 969 970 if (dev) 971 return true; 972 973 return false; 974 } 975 976 static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id) 977 { 978 struct mdesc_handle *hp; 979 struct vdc_port *port; 980 int err; 981 const u64 *ldc_timeout; 982 983 print_version(); 984 985 hp = mdesc_grab(); 986 987 err = -ENODEV; 988 if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) { 989 printk(KERN_ERR PFX "Port id [%llu] too large.\n", 990 vdev->dev_no); 991 goto err_out_release_mdesc; 992 } 993 994 /* Check if this device is part of an mpgroup */ 995 if (vdc_port_mpgroup_check(vdev)) { 996 printk(KERN_WARNING 997 "VIO: Ignoring extra vdisk port %s", 998 dev_name(&vdev->dev)); 999 goto err_out_release_mdesc; 1000 } 1001 1002 port = kzalloc(sizeof(*port), GFP_KERNEL); 1003 err = -ENOMEM; 1004 if (!port) { 1005 printk(KERN_ERR PFX "Cannot allocate vdc_port.\n"); 1006 goto err_out_release_mdesc; 1007 } 1008 1009 if (vdev->dev_no >= 26) 1010 snprintf(port->disk_name, sizeof(port->disk_name), 1011 VDCBLK_NAME "%c%c", 1012 'a' + ((int)vdev->dev_no / 26) - 1, 1013 'a' + ((int)vdev->dev_no % 26)); 1014 else 1015 snprintf(port->disk_name, sizeof(port->disk_name), 1016 VDCBLK_NAME "%c", 'a' + ((int)vdev->dev_no % 26)); 1017 port->vdisk_size = -1; 1018 1019 /* Actual wall time may be double due to do_generic_file_read() doing 1020 * a readahead I/O first, and once that fails it will try to read a 1021 * single page. 1022 */ 1023 ldc_timeout = mdesc_get_property(hp, vdev->mp, "vdc-timeout", NULL); 1024 port->ldc_timeout = ldc_timeout ? *ldc_timeout : 0; 1025 INIT_DELAYED_WORK(&port->ldc_reset_timer_work, vdc_ldc_reset_timer_work); 1026 INIT_WORK(&port->ldc_reset_work, vdc_ldc_reset_work); 1027 1028 err = vio_driver_init(&port->vio, vdev, VDEV_DISK, 1029 vdc_versions, ARRAY_SIZE(vdc_versions), 1030 &vdc_vio_ops, port->disk_name); 1031 if (err) 1032 goto err_out_free_port; 1033 1034 port->vdisk_block_size = VDC_DEFAULT_BLK_SIZE; 1035 port->max_xfer_size = MAX_XFER_SIZE; 1036 port->ring_cookies = MAX_RING_COOKIES; 1037 1038 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port); 1039 if (err) 1040 goto err_out_free_port; 1041 1042 err = vdc_alloc_tx_ring(port); 1043 if (err) 1044 goto err_out_free_ldc; 1045 1046 err = probe_disk(port); 1047 if (err) 1048 goto err_out_free_tx_ring; 1049 1050 /* Note that the device driver_data is used to determine 1051 * whether the port has been probed. 1052 */ 1053 dev_set_drvdata(&vdev->dev, port); 1054 1055 mdesc_release(hp); 1056 1057 return 0; 1058 1059 err_out_free_tx_ring: 1060 vdc_free_tx_ring(port); 1061 1062 err_out_free_ldc: 1063 vio_ldc_free(&port->vio); 1064 1065 err_out_free_port: 1066 kfree(port); 1067 1068 err_out_release_mdesc: 1069 mdesc_release(hp); 1070 return err; 1071 } 1072 1073 static int vdc_port_remove(struct vio_dev *vdev) 1074 { 1075 struct vdc_port *port = dev_get_drvdata(&vdev->dev); 1076 1077 if (port) { 1078 blk_mq_stop_hw_queues(port->disk->queue); 1079 1080 flush_work(&port->ldc_reset_work); 1081 cancel_delayed_work_sync(&port->ldc_reset_timer_work); 1082 del_timer_sync(&port->vio.timer); 1083 1084 del_gendisk(port->disk); 1085 cleanup_queue(port->disk->queue); 1086 put_disk(port->disk); 1087 port->disk = NULL; 1088 1089 vdc_free_tx_ring(port); 1090 vio_ldc_free(&port->vio); 1091 1092 dev_set_drvdata(&vdev->dev, NULL); 1093 1094 kfree(port); 1095 } 1096 return 0; 1097 } 1098 1099 static void vdc_requeue_inflight(struct vdc_port *port) 1100 { 1101 struct vio_dring_state *dr = &port->vio.drings[VIO_DRIVER_TX_RING]; 1102 u32 idx; 1103 1104 for (idx = dr->cons; idx != dr->prod; idx = vio_dring_next(dr, idx)) { 1105 struct vio_disk_desc *desc = vio_dring_entry(dr, idx); 1106 struct vdc_req_entry *rqe = &port->rq_arr[idx]; 1107 struct request *req; 1108 1109 ldc_unmap(port->vio.lp, desc->cookies, desc->ncookies); 1110 desc->hdr.state = VIO_DESC_FREE; 1111 dr->cons = vio_dring_next(dr, idx); 1112 1113 req = rqe->req; 1114 if (req == NULL) { 1115 vdc_end_special(port, desc); 1116 continue; 1117 } 1118 1119 rqe->req = NULL; 1120 blk_mq_requeue_request(req, false); 1121 } 1122 } 1123 1124 static void vdc_queue_drain(struct vdc_port *port) 1125 { 1126 struct request_queue *q = port->disk->queue; 1127 1128 /* 1129 * Mark the queue as draining, then freeze/quiesce to ensure 1130 * that all existing requests are seen in ->queue_rq() and killed 1131 */ 1132 port->drain = 1; 1133 spin_unlock_irq(&port->vio.lock); 1134 1135 blk_mq_freeze_queue(q); 1136 blk_mq_quiesce_queue(q); 1137 1138 spin_lock_irq(&port->vio.lock); 1139 port->drain = 0; 1140 blk_mq_unquiesce_queue(q); 1141 blk_mq_unfreeze_queue(q); 1142 } 1143 1144 static void vdc_ldc_reset_timer_work(struct work_struct *work) 1145 { 1146 struct vdc_port *port; 1147 struct vio_driver_state *vio; 1148 1149 port = container_of(work, struct vdc_port, ldc_reset_timer_work.work); 1150 vio = &port->vio; 1151 1152 spin_lock_irq(&vio->lock); 1153 if (!(port->vio.hs_state & VIO_HS_COMPLETE)) { 1154 pr_warn(PFX "%s ldc down %llu seconds, draining queue\n", 1155 port->disk_name, port->ldc_timeout); 1156 vdc_queue_drain(port); 1157 vdc_blk_queue_start(port); 1158 } 1159 spin_unlock_irq(&vio->lock); 1160 } 1161 1162 static void vdc_ldc_reset_work(struct work_struct *work) 1163 { 1164 struct vdc_port *port; 1165 struct vio_driver_state *vio; 1166 unsigned long flags; 1167 1168 port = container_of(work, struct vdc_port, ldc_reset_work); 1169 vio = &port->vio; 1170 1171 spin_lock_irqsave(&vio->lock, flags); 1172 vdc_ldc_reset(port); 1173 spin_unlock_irqrestore(&vio->lock, flags); 1174 } 1175 1176 static void vdc_ldc_reset(struct vdc_port *port) 1177 { 1178 int err; 1179 1180 assert_spin_locked(&port->vio.lock); 1181 1182 pr_warn(PFX "%s ldc link reset\n", port->disk_name); 1183 blk_mq_stop_hw_queues(port->disk->queue); 1184 vdc_requeue_inflight(port); 1185 vdc_port_down(port); 1186 1187 err = vio_ldc_alloc(&port->vio, &vdc_ldc_cfg, port); 1188 if (err) { 1189 pr_err(PFX "%s vio_ldc_alloc:%d\n", port->disk_name, err); 1190 return; 1191 } 1192 1193 err = vdc_alloc_tx_ring(port); 1194 if (err) { 1195 pr_err(PFX "%s vio_alloc_tx_ring:%d\n", port->disk_name, err); 1196 goto err_free_ldc; 1197 } 1198 1199 if (port->ldc_timeout) 1200 mod_delayed_work(system_wq, &port->ldc_reset_timer_work, 1201 round_jiffies(jiffies + HZ * port->ldc_timeout)); 1202 mod_timer(&port->vio.timer, round_jiffies(jiffies + HZ)); 1203 return; 1204 1205 err_free_ldc: 1206 vio_ldc_free(&port->vio); 1207 } 1208 1209 static const struct vio_device_id vdc_port_match[] = { 1210 { 1211 .type = "vdc-port", 1212 }, 1213 {}, 1214 }; 1215 MODULE_DEVICE_TABLE(vio, vdc_port_match); 1216 1217 static struct vio_driver vdc_port_driver = { 1218 .id_table = vdc_port_match, 1219 .probe = vdc_port_probe, 1220 .remove = vdc_port_remove, 1221 .name = "vdc_port", 1222 }; 1223 1224 static int __init vdc_init(void) 1225 { 1226 int err; 1227 1228 sunvdc_wq = alloc_workqueue("sunvdc", 0, 0); 1229 if (!sunvdc_wq) 1230 return -ENOMEM; 1231 1232 err = register_blkdev(0, VDCBLK_NAME); 1233 if (err < 0) 1234 goto out_free_wq; 1235 1236 vdc_major = err; 1237 1238 err = vio_register_driver(&vdc_port_driver); 1239 if (err) 1240 goto out_unregister_blkdev; 1241 1242 return 0; 1243 1244 out_unregister_blkdev: 1245 unregister_blkdev(vdc_major, VDCBLK_NAME); 1246 vdc_major = 0; 1247 1248 out_free_wq: 1249 destroy_workqueue(sunvdc_wq); 1250 return err; 1251 } 1252 1253 static void __exit vdc_exit(void) 1254 { 1255 vio_unregister_driver(&vdc_port_driver); 1256 unregister_blkdev(vdc_major, VDCBLK_NAME); 1257 destroy_workqueue(sunvdc_wq); 1258 } 1259 1260 module_init(vdc_init); 1261 module_exit(vdc_exit); 1262