1 /*- 2 * Copyright (c) 2011 NetApp, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/linker_set.h> 34 #include <sys/stat.h> 35 #include <sys/uio.h> 36 #include <sys/ioctl.h> 37 #include <sys/disk.h> 38 39 #include <errno.h> 40 #include <fcntl.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <stdint.h> 44 #include <string.h> 45 #include <strings.h> 46 #include <unistd.h> 47 #include <assert.h> 48 #include <pthread.h> 49 50 #include "bhyverun.h" 51 #include "pci_emul.h" 52 #include "virtio.h" 53 54 #define VTBLK_RINGSZ 64 55 56 #define VTBLK_CFGSZ 28 57 58 #define VTBLK_R_CFG VTCFG_R_CFG1 59 #define VTBLK_R_CFG_END VTBLK_R_CFG + VTBLK_CFGSZ -1 60 #define VTBLK_R_MAX VTBLK_R_CFG_END 61 62 #define VTBLK_REGSZ VTBLK_R_MAX+1 63 64 #define VTBLK_MAXSEGS 32 65 66 #define VTBLK_S_OK 0 67 #define VTBLK_S_IOERR 1 68 69 /* 70 * Host capabilities 71 */ 72 #define VTBLK_S_HOSTCAPS \ 73 ( 0x00000004 | /* host maximum request segments */ \ 74 0x10000000 ) /* supports indirect descriptors */ 75 76 static int use_msix = 1; 77 78 struct vring_hqueue { 79 /* Internal state */ 80 uint16_t hq_size; 81 uint16_t hq_cur_aidx; /* trails behind 'avail_idx' */ 82 83 /* Host-context pointers to the queue */ 84 struct virtio_desc *hq_dtable; 85 uint16_t *hq_avail_flags; 86 uint16_t *hq_avail_idx; /* monotonically increasing */ 87 uint16_t *hq_avail_ring; 88 89 uint16_t *hq_used_flags; 90 uint16_t *hq_used_idx; /* monotonically increasing */ 91 struct virtio_used *hq_used_ring; 92 }; 93 94 /* 95 * Config space 96 */ 97 struct vtblk_config { 98 uint64_t vbc_capacity; 99 uint32_t vbc_size_max; 100 uint32_t vbc_seg_max; 101 uint16_t vbc_geom_c; 102 uint8_t vbc_geom_h; 103 uint8_t vbc_geom_s; 104 uint32_t vbc_blk_size; 105 uint32_t vbc_sectors_max; 106 } __packed; 107 CTASSERT(sizeof(struct vtblk_config) == VTBLK_CFGSZ); 108 109 /* 110 * Fixed-size block header 111 */ 112 struct virtio_blk_hdr { 113 #define VBH_OP_READ 0 114 #define VBH_OP_WRITE 1 115 #define VBH_FLAG_BARRIER 0x80000000 /* OR'ed into vbh_type */ 116 uint32_t vbh_type; 117 uint32_t vbh_ioprio; 118 uint64_t vbh_sector; 119 } __packed; 120 121 /* 122 * Debug printf 123 */ 124 static int pci_vtblk_debug; 125 #define DPRINTF(params) if (pci_vtblk_debug) printf params 126 #define WPRINTF(params) printf params 127 128 /* 129 * Per-device softc 130 */ 131 struct pci_vtblk_softc { 132 struct pci_devinst *vbsc_pi; 133 int vbsc_fd; 134 int vbsc_status; 135 int vbsc_isr; 136 int vbsc_lastq; 137 uint32_t vbsc_features; 138 uint64_t vbsc_pfn; 139 struct vring_hqueue vbsc_q; 140 struct vtblk_config vbsc_cfg; 141 uint16_t msix_table_idx_req; 142 uint16_t msix_table_idx_cfg; 143 }; 144 #define vtblk_ctx(sc) ((sc)->vbsc_pi->pi_vmctx) 145 146 /* 147 * Return the size of IO BAR that maps virtio header and device specific 148 * region. The size would vary depending on whether MSI-X is enabled or 149 * not 150 */ 151 static uint64_t 152 pci_vtblk_iosize(struct pci_devinst *pi) 153 { 154 155 if (pci_msix_enabled(pi)) 156 return (VTBLK_REGSZ); 157 else 158 return (VTBLK_REGSZ - (VTCFG_R_CFG1 - VTCFG_R_MSIX)); 159 } 160 161 /* 162 * Return the number of available descriptors in the vring taking care 163 * of the 16-bit index wraparound. 164 */ 165 static int 166 hq_num_avail(struct vring_hqueue *hq) 167 { 168 uint16_t ndesc; 169 170 /* 171 * We're just computing (a-b) in GF(216). 172 * 173 * The only glitch here is that in standard C, 174 * uint16_t promotes to (signed) int when int has 175 * more than 16 bits (pretty much always now), so 176 * we have to force it back to unsigned. 177 */ 178 ndesc = (unsigned)*hq->hq_avail_idx - (unsigned)hq->hq_cur_aidx; 179 180 assert(ndesc <= hq->hq_size); 181 182 return (ndesc); 183 } 184 185 static void 186 pci_vtblk_update_status(struct pci_vtblk_softc *sc, uint32_t value) 187 { 188 if (value == 0) { 189 DPRINTF(("vtblk: device reset requested !\n")); 190 sc->vbsc_isr = 0; 191 sc->msix_table_idx_req = VIRTIO_MSI_NO_VECTOR; 192 sc->msix_table_idx_cfg = VIRTIO_MSI_NO_VECTOR; 193 sc->vbsc_features = 0; 194 sc->vbsc_pfn = 0; 195 sc->vbsc_lastq = 0; 196 memset(&sc->vbsc_q, 0, sizeof(struct vring_hqueue)); 197 } 198 199 sc->vbsc_status = value; 200 } 201 202 static void 203 pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vring_hqueue *hq) 204 { 205 struct iovec iov[VTBLK_MAXSEGS]; 206 struct virtio_blk_hdr *vbh; 207 struct virtio_desc *vd, *vid; 208 struct virtio_used *vu; 209 uint8_t *status; 210 int i; 211 int err; 212 int iolen; 213 int uidx, aidx, didx; 214 int indirect, writeop, type; 215 off_t offset; 216 217 uidx = *hq->hq_used_idx; 218 aidx = hq->hq_cur_aidx; 219 didx = hq->hq_avail_ring[aidx % hq->hq_size]; 220 assert(didx >= 0 && didx < hq->hq_size); 221 222 vd = &hq->hq_dtable[didx]; 223 224 indirect = ((vd->vd_flags & VRING_DESC_F_INDIRECT) != 0); 225 226 if (indirect) { 227 vid = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, vd->vd_len); 228 vd = &vid[0]; 229 } 230 231 /* 232 * The first descriptor will be the read-only fixed header 233 */ 234 vbh = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, 235 sizeof(struct virtio_blk_hdr)); 236 assert(vd->vd_len == sizeof(struct virtio_blk_hdr)); 237 assert(vd->vd_flags & VRING_DESC_F_NEXT); 238 assert((vd->vd_flags & VRING_DESC_F_WRITE) == 0); 239 240 /* 241 * XXX 242 * The guest should not be setting the BARRIER flag because 243 * we don't advertise the capability. 244 */ 245 type = vbh->vbh_type & ~VBH_FLAG_BARRIER; 246 writeop = (type == VBH_OP_WRITE); 247 248 offset = vbh->vbh_sector * DEV_BSIZE; 249 250 /* 251 * Build up the iovec based on the guest's data descriptors 252 */ 253 i = iolen = 0; 254 while (1) { 255 if (indirect) 256 vd = &vid[i + 1]; /* skip first indirect desc */ 257 else 258 vd = &hq->hq_dtable[vd->vd_next]; 259 260 if ((vd->vd_flags & VRING_DESC_F_NEXT) == 0) 261 break; 262 263 if (i == VTBLK_MAXSEGS) 264 break; 265 266 /* 267 * - write op implies read-only descriptor, 268 * - read op implies write-only descriptor, 269 * therefore test the inverse of the descriptor bit 270 * to the op. 271 */ 272 assert(((vd->vd_flags & VRING_DESC_F_WRITE) == 0) == 273 writeop); 274 275 iov[i].iov_base = paddr_guest2host(vtblk_ctx(sc), 276 vd->vd_addr, 277 vd->vd_len); 278 iov[i].iov_len = vd->vd_len; 279 iolen += vd->vd_len; 280 i++; 281 } 282 283 /* Lastly, get the address of the status byte */ 284 status = paddr_guest2host(vtblk_ctx(sc), vd->vd_addr, 1); 285 assert(vd->vd_len == 1); 286 assert((vd->vd_flags & VRING_DESC_F_NEXT) == 0); 287 assert(vd->vd_flags & VRING_DESC_F_WRITE); 288 289 DPRINTF(("virtio-block: %s op, %d bytes, %d segs, offset %ld\n\r", 290 writeop ? "write" : "read", iolen, i, offset)); 291 292 if (writeop) 293 err = pwritev(sc->vbsc_fd, iov, i, offset); 294 else 295 err = preadv(sc->vbsc_fd, iov, i, offset); 296 297 *status = err < 0 ? VTBLK_S_IOERR : VTBLK_S_OK; 298 299 /* 300 * Return the single descriptor back to the host 301 */ 302 vu = &hq->hq_used_ring[uidx % hq->hq_size]; 303 vu->vu_idx = didx; 304 vu->vu_tlen = 1; 305 hq->hq_cur_aidx++; 306 *hq->hq_used_idx += 1; 307 308 /* 309 * Generate an interrupt if able 310 */ 311 if ((*hq->hq_avail_flags & VRING_AVAIL_F_NO_INTERRUPT) == 0) { 312 if (use_msix) { 313 pci_generate_msix(sc->vbsc_pi, sc->msix_table_idx_req); 314 } else if (sc->vbsc_isr == 0) { 315 sc->vbsc_isr = 1; 316 pci_generate_msi(sc->vbsc_pi, 0); 317 } 318 } 319 } 320 321 static void 322 pci_vtblk_qnotify(struct pci_vtblk_softc *sc) 323 { 324 struct vring_hqueue *hq = &sc->vbsc_q; 325 int ndescs; 326 327 while ((ndescs = hq_num_avail(hq)) != 0) { 328 /* 329 * Run through all the entries, placing them into iovecs and 330 * sending when an end-of-packet is found 331 */ 332 pci_vtblk_proc(sc, hq); 333 } 334 } 335 336 static void 337 pci_vtblk_ring_init(struct pci_vtblk_softc *sc, uint64_t pfn) 338 { 339 struct vring_hqueue *hq; 340 341 sc->vbsc_pfn = pfn << VRING_PFN; 342 343 /* 344 * Set up host pointers to the various parts of the 345 * queue 346 */ 347 hq = &sc->vbsc_q; 348 hq->hq_size = VTBLK_RINGSZ; 349 350 hq->hq_dtable = paddr_guest2host(vtblk_ctx(sc), pfn << VRING_PFN, 351 vring_size(VTBLK_RINGSZ)); 352 hq->hq_avail_flags = (uint16_t *)(hq->hq_dtable + hq->hq_size); 353 hq->hq_avail_idx = hq->hq_avail_flags + 1; 354 hq->hq_avail_ring = hq->hq_avail_flags + 2; 355 hq->hq_used_flags = (uint16_t *)roundup2((uintptr_t)hq->hq_avail_ring, 356 VRING_ALIGN); 357 hq->hq_used_idx = hq->hq_used_flags + 1; 358 hq->hq_used_ring = (struct virtio_used *)(hq->hq_used_flags + 2); 359 360 /* 361 * Initialize queue indexes 362 */ 363 hq->hq_cur_aidx = 0; 364 } 365 366 static int 367 pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts) 368 { 369 struct stat sbuf; 370 struct pci_vtblk_softc *sc; 371 off_t size; 372 int fd; 373 int sectsz; 374 const char *env_msi; 375 376 if (opts == NULL) { 377 printf("virtio-block: backing device required\n"); 378 return (1); 379 } 380 381 /* 382 * The supplied backing file has to exist 383 */ 384 fd = open(opts, O_RDWR); 385 if (fd < 0) { 386 perror("Could not open backing file"); 387 return (1); 388 } 389 390 if (fstat(fd, &sbuf) < 0) { 391 perror("Could not stat backing file"); 392 close(fd); 393 return (1); 394 } 395 396 /* 397 * Deal with raw devices 398 */ 399 size = sbuf.st_size; 400 sectsz = DEV_BSIZE; 401 if (S_ISCHR(sbuf.st_mode)) { 402 if (ioctl(fd, DIOCGMEDIASIZE, &size) < 0 || 403 ioctl(fd, DIOCGSECTORSIZE, §sz)) { 404 perror("Could not fetch dev blk/sector size"); 405 close(fd); 406 return (1); 407 } 408 assert(size != 0); 409 assert(sectsz != 0); 410 } 411 412 sc = malloc(sizeof(struct pci_vtblk_softc)); 413 memset(sc, 0, sizeof(struct pci_vtblk_softc)); 414 415 pi->pi_arg = sc; 416 sc->vbsc_pi = pi; 417 sc->vbsc_fd = fd; 418 419 /* setup virtio block config space */ 420 sc->vbsc_cfg.vbc_capacity = size / sectsz; 421 sc->vbsc_cfg.vbc_seg_max = VTBLK_MAXSEGS; 422 sc->vbsc_cfg.vbc_blk_size = sectsz; 423 sc->vbsc_cfg.vbc_size_max = 0; /* not negotiated */ 424 sc->vbsc_cfg.vbc_geom_c = 0; /* no geometry */ 425 sc->vbsc_cfg.vbc_geom_h = 0; 426 sc->vbsc_cfg.vbc_geom_s = 0; 427 sc->vbsc_cfg.vbc_sectors_max = 0; 428 429 /* initialize config space */ 430 pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_BLOCK); 431 pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR); 432 pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE); 433 pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_TYPE_BLOCK); 434 435 if ((env_msi = getenv("BHYVE_USE_MSI"))) { 436 if (strcasecmp(env_msi, "yes") == 0) 437 use_msix = 0; 438 } 439 440 if (use_msix) { 441 /* MSI-X Support */ 442 sc->msix_table_idx_req = VIRTIO_MSI_NO_VECTOR; 443 sc->msix_table_idx_cfg = VIRTIO_MSI_NO_VECTOR; 444 445 if (pci_emul_add_msixcap(pi, 2, 1)) 446 return (1); 447 } else { 448 /* MSI Support */ 449 pci_emul_add_msicap(pi, 1); 450 } 451 452 pci_emul_alloc_bar(pi, 0, PCIBAR_IO, VTBLK_REGSZ); 453 454 return (0); 455 } 456 457 static uint64_t 458 vtblk_adjust_offset(struct pci_devinst *pi, uint64_t offset) 459 { 460 /* 461 * Device specific offsets used by guest would change 462 * based on whether MSI-X capability is enabled or not 463 */ 464 if (!pci_msix_enabled(pi)) { 465 if (offset >= VTCFG_R_MSIX) 466 return (offset + (VTCFG_R_CFG1 - VTCFG_R_MSIX)); 467 } 468 469 return (offset); 470 } 471 472 static void 473 pci_vtblk_write(struct vmctx *ctx, int vcpu, struct pci_devinst *pi, 474 int baridx, uint64_t offset, int size, uint64_t value) 475 { 476 struct pci_vtblk_softc *sc = pi->pi_arg; 477 478 if (use_msix) { 479 if (baridx == pci_msix_table_bar(pi) || 480 baridx == pci_msix_pba_bar(pi)) { 481 pci_emul_msix_twrite(pi, offset, size, value); 482 return; 483 } 484 } 485 486 assert(baridx == 0); 487 488 if (offset + size > pci_vtblk_iosize(pi)) { 489 DPRINTF(("vtblk_write: 2big, offset %ld size %d\n", 490 offset, size)); 491 return; 492 } 493 494 offset = vtblk_adjust_offset(pi, offset); 495 496 switch (offset) { 497 case VTCFG_R_GUESTCAP: 498 assert(size == 4); 499 sc->vbsc_features = value & VTBLK_S_HOSTCAPS; 500 break; 501 case VTCFG_R_PFN: 502 assert(size == 4); 503 pci_vtblk_ring_init(sc, value); 504 break; 505 case VTCFG_R_QSEL: 506 assert(size == 2); 507 sc->vbsc_lastq = value; 508 break; 509 case VTCFG_R_QNOTIFY: 510 assert(size == 2); 511 assert(value == 0); 512 pci_vtblk_qnotify(sc); 513 break; 514 case VTCFG_R_STATUS: 515 assert(size == 1); 516 pci_vtblk_update_status(sc, value); 517 break; 518 case VTCFG_R_CFGVEC: 519 assert(size == 2); 520 sc->msix_table_idx_cfg = value; 521 break; 522 case VTCFG_R_QVEC: 523 assert(size == 2); 524 sc->msix_table_idx_req = value; 525 break; 526 case VTCFG_R_HOSTCAP: 527 case VTCFG_R_QNUM: 528 case VTCFG_R_ISR: 529 case VTBLK_R_CFG ... VTBLK_R_CFG_END: 530 DPRINTF(("vtblk: write to readonly reg %ld\n\r", offset)); 531 break; 532 default: 533 DPRINTF(("vtblk: unknown i/o write offset %ld\n\r", offset)); 534 value = 0; 535 break; 536 } 537 } 538 539 uint64_t 540 pci_vtblk_read(struct vmctx *ctx, int vcpu, struct pci_devinst *pi, 541 int baridx, uint64_t offset, int size) 542 { 543 struct pci_vtblk_softc *sc = pi->pi_arg; 544 void *ptr; 545 uint32_t value; 546 547 if (use_msix) { 548 if (baridx == pci_msix_table_bar(pi) || 549 baridx == pci_msix_pba_bar(pi)) { 550 return (pci_emul_msix_tread(pi, offset, size)); 551 } 552 } 553 554 assert(baridx == 0); 555 556 if (offset + size > pci_vtblk_iosize(pi)) { 557 DPRINTF(("vtblk_read: 2big, offset %ld size %d\n", 558 offset, size)); 559 return (0); 560 } 561 562 offset = vtblk_adjust_offset(pi, offset); 563 564 switch (offset) { 565 case VTCFG_R_HOSTCAP: 566 assert(size == 4); 567 value = VTBLK_S_HOSTCAPS; 568 break; 569 case VTCFG_R_GUESTCAP: 570 assert(size == 4); 571 value = sc->vbsc_features; /* XXX never read ? */ 572 break; 573 case VTCFG_R_PFN: 574 assert(size == 4); 575 value = sc->vbsc_pfn >> VRING_PFN; 576 break; 577 case VTCFG_R_QNUM: 578 value = (sc->vbsc_lastq == 0) ? VTBLK_RINGSZ: 0; 579 break; 580 case VTCFG_R_QSEL: 581 assert(size == 2); 582 value = sc->vbsc_lastq; /* XXX never read ? */ 583 break; 584 case VTCFG_R_QNOTIFY: 585 assert(size == 2); 586 value = 0; /* XXX never read ? */ 587 break; 588 case VTCFG_R_STATUS: 589 assert(size == 1); 590 value = sc->vbsc_status; 591 break; 592 case VTCFG_R_ISR: 593 assert(size == 1); 594 value = sc->vbsc_isr; 595 sc->vbsc_isr = 0; /* a read clears this flag */ 596 break; 597 case VTCFG_R_CFGVEC: 598 assert(size == 2); 599 value = sc->msix_table_idx_cfg; 600 break; 601 case VTCFG_R_QVEC: 602 assert(size == 2); 603 value = sc->msix_table_idx_req; 604 break; 605 case VTBLK_R_CFG ... VTBLK_R_CFG_END: 606 assert(size + offset <= (VTBLK_R_CFG_END + 1)); 607 ptr = (uint8_t *)&sc->vbsc_cfg + offset - VTBLK_R_CFG; 608 if (size == 1) { 609 value = *(uint8_t *) ptr; 610 } else if (size == 2) { 611 value = *(uint16_t *) ptr; 612 } else { 613 value = *(uint32_t *) ptr; 614 } 615 break; 616 default: 617 DPRINTF(("vtblk: unknown i/o read offset %ld\n\r", offset)); 618 value = 0; 619 break; 620 } 621 622 return (value); 623 } 624 625 struct pci_devemu pci_de_vblk = { 626 .pe_emu = "virtio-blk", 627 .pe_init = pci_vtblk_init, 628 .pe_barwrite = pci_vtblk_write, 629 .pe_barread = pci_vtblk_read 630 }; 631 PCI_EMUL_SET(pci_de_vblk); 632