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