pci_virtio_block.c revision 280749
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: stable/10/usr.sbin/bhyve/pci_virtio_block.c 280749 2015-03-27 08:58:30Z mav $ 27 */ 28 29#include <sys/cdefs.h> 30__FBSDID("$FreeBSD: stable/10/usr.sbin/bhyve/pci_virtio_block.c 280749 2015-03-27 08:58:30Z mav $"); 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#include <md5.h> 50 51#include "bhyverun.h" 52#include "pci_emul.h" 53#include "virtio.h" 54#include "block_if.h" 55 56#define VTBLK_RINGSZ 64 57 58#define VTBLK_S_OK 0 59#define VTBLK_S_IOERR 1 60#define VTBLK_S_UNSUPP 2 61 62#define VTBLK_BLK_ID_BYTES 20 63 64/* Capability bits */ 65#define VTBLK_F_SEG_MAX (1 << 2) /* Maximum request segments */ 66#define VTBLK_F_BLK_SIZE (1 << 6) /* cfg block size valid */ 67#define VTBLK_F_TOPOLOGY (1 << 10) /* Optimal I/O alignment */ 68 69/* 70 * Host capabilities 71 */ 72#define VTBLK_S_HOSTCAPS \ 73 ( VTBLK_F_SEG_MAX | \ 74 VTBLK_F_BLK_SIZE | \ 75 VTBLK_F_TOPOLOGY | \ 76 VIRTIO_RING_F_INDIRECT_DESC ) /* indirect descriptors */ 77 78/* 79 * Config space "registers" 80 */ 81struct vtblk_config { 82 uint64_t vbc_capacity; 83 uint32_t vbc_size_max; 84 uint32_t vbc_seg_max; 85 struct { 86 uint16_t cylinders; 87 uint8_t heads; 88 uint8_t sectors; 89 } vbc_geometry; 90 uint32_t vbc_blk_size; 91 struct { 92 uint8_t physical_block_exp; 93 uint8_t alignment_offset; 94 uint16_t min_io_size; 95 uint32_t opt_io_size; 96 } vbc_topology; 97 uint8_t vbc_writeback; 98} __packed; 99 100/* 101 * Fixed-size block header 102 */ 103struct virtio_blk_hdr { 104#define VBH_OP_READ 0 105#define VBH_OP_WRITE 1 106#define VBH_OP_FLUSH 4 107#define VBH_OP_FLUSH_OUT 5 108#define VBH_OP_IDENT 8 109#define VBH_FLAG_BARRIER 0x80000000 /* OR'ed into vbh_type */ 110 uint32_t vbh_type; 111 uint32_t vbh_ioprio; 112 uint64_t vbh_sector; 113} __packed; 114 115/* 116 * Debug printf 117 */ 118static int pci_vtblk_debug; 119#define DPRINTF(params) if (pci_vtblk_debug) printf params 120#define WPRINTF(params) printf params 121 122struct pci_vtblk_ioreq { 123 struct blockif_req io_req; 124 struct pci_vtblk_softc *io_sc; 125 uint8_t *io_status; 126 uint16_t io_idx; 127}; 128 129/* 130 * Per-device softc 131 */ 132struct pci_vtblk_softc { 133 struct virtio_softc vbsc_vs; 134 pthread_mutex_t vsc_mtx; 135 struct vqueue_info vbsc_vq; 136 struct vtblk_config vbsc_cfg; 137 struct blockif_ctxt *bc; 138 char vbsc_ident[VTBLK_BLK_ID_BYTES]; 139 struct pci_vtblk_ioreq vbsc_ios[VTBLK_RINGSZ]; 140}; 141 142static void pci_vtblk_reset(void *); 143static void pci_vtblk_notify(void *, struct vqueue_info *); 144static int pci_vtblk_cfgread(void *, int, int, uint32_t *); 145static int pci_vtblk_cfgwrite(void *, int, int, uint32_t); 146 147static struct virtio_consts vtblk_vi_consts = { 148 "vtblk", /* our name */ 149 1, /* we support 1 virtqueue */ 150 sizeof(struct vtblk_config), /* config reg size */ 151 pci_vtblk_reset, /* reset */ 152 pci_vtblk_notify, /* device-wide qnotify */ 153 pci_vtblk_cfgread, /* read PCI config */ 154 pci_vtblk_cfgwrite, /* write PCI config */ 155 NULL, /* apply negotiated features */ 156 VTBLK_S_HOSTCAPS, /* our capabilities */ 157}; 158 159static void 160pci_vtblk_reset(void *vsc) 161{ 162 struct pci_vtblk_softc *sc = vsc; 163 164 DPRINTF(("vtblk: device reset requested !\n")); 165 vi_reset_dev(&sc->vbsc_vs); 166} 167 168static void 169pci_vtblk_done(struct blockif_req *br, int err) 170{ 171 struct pci_vtblk_ioreq *io = br->br_param; 172 struct pci_vtblk_softc *sc = io->io_sc; 173 174 /* convert errno into a virtio block error return */ 175 if (err == EOPNOTSUPP || err == ENOSYS) 176 *io->io_status = VTBLK_S_UNSUPP; 177 else if (err != 0) 178 *io->io_status = VTBLK_S_IOERR; 179 else 180 *io->io_status = VTBLK_S_OK; 181 182 /* 183 * Return the descriptor back to the host. 184 * We wrote 1 byte (our status) to host. 185 */ 186 pthread_mutex_lock(&sc->vsc_mtx); 187 vq_relchain(&sc->vbsc_vq, io->io_idx, 1); 188 vq_endchains(&sc->vbsc_vq, 0); 189 pthread_mutex_unlock(&sc->vsc_mtx); 190} 191 192static void 193pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vqueue_info *vq) 194{ 195 struct virtio_blk_hdr *vbh; 196 struct pci_vtblk_ioreq *io; 197 int i, n; 198 int err; 199 int iolen; 200 int writeop, type; 201 off_t offset; 202 struct iovec iov[BLOCKIF_IOV_MAX + 2]; 203 uint16_t idx, flags[BLOCKIF_IOV_MAX + 2]; 204 205 n = vq_getchain(vq, &idx, iov, BLOCKIF_IOV_MAX + 2, flags); 206 207 /* 208 * The first descriptor will be the read-only fixed header, 209 * and the last is for status (hence +2 above and below). 210 * The remaining iov's are the actual data I/O vectors. 211 * 212 * XXX - note - this fails on crash dump, which does a 213 * VIRTIO_BLK_T_FLUSH with a zero transfer length 214 */ 215 assert(n >= 2 && n <= BLOCKIF_IOV_MAX + 2); 216 217 io = &sc->vbsc_ios[idx]; 218 assert((flags[0] & VRING_DESC_F_WRITE) == 0); 219 assert(iov[0].iov_len == sizeof(struct virtio_blk_hdr)); 220 vbh = iov[0].iov_base; 221 memcpy(&io->io_req.br_iov, &iov[1], sizeof(struct iovec) * (n - 2)); 222 io->io_req.br_iovcnt = n - 2; 223 io->io_req.br_offset = vbh->vbh_sector * DEV_BSIZE; 224 io->io_status = iov[--n].iov_base; 225 assert(iov[n].iov_len == 1); 226 assert(flags[n] & VRING_DESC_F_WRITE); 227 228 /* 229 * XXX 230 * The guest should not be setting the BARRIER flag because 231 * we don't advertise the capability. 232 */ 233 type = vbh->vbh_type & ~VBH_FLAG_BARRIER; 234 writeop = (type == VBH_OP_WRITE); 235 236 iolen = 0; 237 for (i = 1; i < n; i++) { 238 /* 239 * - write op implies read-only descriptor, 240 * - read/ident op implies write-only descriptor, 241 * therefore test the inverse of the descriptor bit 242 * to the op. 243 */ 244 assert(((flags[i] & VRING_DESC_F_WRITE) == 0) == writeop); 245 iolen += iov[i].iov_len; 246 } 247 248 DPRINTF(("virtio-block: %s op, %d bytes, %d segs, offset %ld\n\r", 249 writeop ? "write" : "read/ident", iolen, i - 1, offset)); 250 251 switch (type) { 252 case VBH_OP_READ: 253 err = blockif_read(sc->bc, &io->io_req); 254 break; 255 case VBH_OP_WRITE: 256 err = blockif_write(sc->bc, &io->io_req); 257 break; 258 case VBH_OP_FLUSH: 259 case VBH_OP_FLUSH_OUT: 260 err = blockif_flush(sc->bc, &io->io_req); 261 break; 262 case VBH_OP_IDENT: 263 /* Assume a single buffer */ 264 /* S/n equal to buffer is not zero-terminated. */ 265 memset(iov[1].iov_base, 0, iov[1].iov_len); 266 strncpy(iov[1].iov_base, sc->vbsc_ident, 267 MIN(iov[1].iov_len, sizeof(sc->vbsc_ident))); 268 pci_vtblk_done(&io->io_req, 0); 269 return; 270 default: 271 pci_vtblk_done(&io->io_req, EOPNOTSUPP); 272 return; 273 } 274 assert(err == 0); 275} 276 277static void 278pci_vtblk_notify(void *vsc, struct vqueue_info *vq) 279{ 280 struct pci_vtblk_softc *sc = vsc; 281 282 while (vq_has_descs(vq)) 283 pci_vtblk_proc(sc, vq); 284} 285 286static int 287pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts) 288{ 289 char bident[sizeof("XX:X:X")]; 290 struct blockif_ctxt *bctxt; 291 MD5_CTX mdctx; 292 u_char digest[16]; 293 struct pci_vtblk_softc *sc; 294 off_t size; 295 int i, sectsz, sts, sto; 296 297 if (opts == NULL) { 298 printf("virtio-block: backing device required\n"); 299 return (1); 300 } 301 302 /* 303 * The supplied backing file has to exist 304 */ 305 snprintf(bident, sizeof(bident), "%d:%d", pi->pi_slot, pi->pi_func); 306 bctxt = blockif_open(opts, bident); 307 if (bctxt == NULL) { 308 perror("Could not open backing file"); 309 return (1); 310 } 311 312 size = blockif_size(bctxt); 313 sectsz = blockif_sectsz(bctxt); 314 blockif_psectsz(bctxt, &sts, &sto); 315 316 sc = calloc(1, sizeof(struct pci_vtblk_softc)); 317 sc->bc = bctxt; 318 for (i = 0; i < VTBLK_RINGSZ; i++) { 319 struct pci_vtblk_ioreq *io = &sc->vbsc_ios[i]; 320 io->io_req.br_callback = pci_vtblk_done; 321 io->io_req.br_param = io; 322 io->io_sc = sc; 323 io->io_idx = i; 324 } 325 326 pthread_mutex_init(&sc->vsc_mtx, NULL); 327 328 /* init virtio softc and virtqueues */ 329 vi_softc_linkup(&sc->vbsc_vs, &vtblk_vi_consts, sc, pi, &sc->vbsc_vq); 330 sc->vbsc_vs.vs_mtx = &sc->vsc_mtx; 331 332 sc->vbsc_vq.vq_qsize = VTBLK_RINGSZ; 333 /* sc->vbsc_vq.vq_notify = we have no per-queue notify */ 334 335 /* 336 * Create an identifier for the backing file. Use parts of the 337 * md5 sum of the filename 338 */ 339 MD5Init(&mdctx); 340 MD5Update(&mdctx, opts, strlen(opts)); 341 MD5Final(digest, &mdctx); 342 sprintf(sc->vbsc_ident, "BHYVE-%02X%02X-%02X%02X-%02X%02X", 343 digest[0], digest[1], digest[2], digest[3], digest[4], digest[5]); 344 345 /* setup virtio block config space */ 346 sc->vbsc_cfg.vbc_capacity = size / DEV_BSIZE; /* 512-byte units */ 347 sc->vbsc_cfg.vbc_size_max = 0; /* not negotiated */ 348 sc->vbsc_cfg.vbc_seg_max = BLOCKIF_IOV_MAX; 349 sc->vbsc_cfg.vbc_geometry.cylinders = 0; /* no geometry */ 350 sc->vbsc_cfg.vbc_geometry.heads = 0; 351 sc->vbsc_cfg.vbc_geometry.sectors = 0; 352 sc->vbsc_cfg.vbc_blk_size = sectsz; 353 sc->vbsc_cfg.vbc_topology.physical_block_exp = 354 (sts > sectsz) ? (ffsll(sts / sectsz) - 1) : 0; 355 sc->vbsc_cfg.vbc_topology.alignment_offset = 356 (sto != 0) ? ((sts - sto) / sectsz) : 0; 357 sc->vbsc_cfg.vbc_topology.min_io_size = 0; 358 sc->vbsc_cfg.vbc_topology.opt_io_size = 0; 359 sc->vbsc_cfg.vbc_writeback = 0; 360 361 /* 362 * Should we move some of this into virtio.c? Could 363 * have the device, class, and subdev_0 as fields in 364 * the virtio constants structure. 365 */ 366 pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_BLOCK); 367 pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR); 368 pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE); 369 pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_TYPE_BLOCK); 370 371 pci_lintr_request(pi); 372 373 if (vi_intr_init(&sc->vbsc_vs, 1, fbsdrun_virtio_msix())) { 374 blockif_close(sc->bc); 375 free(sc); 376 return (1); 377 } 378 vi_set_io_bar(&sc->vbsc_vs, 0); 379 return (0); 380} 381 382static int 383pci_vtblk_cfgwrite(void *vsc, int offset, int size, uint32_t value) 384{ 385 386 DPRINTF(("vtblk: write to readonly reg %d\n\r", offset)); 387 return (1); 388} 389 390static int 391pci_vtblk_cfgread(void *vsc, int offset, int size, uint32_t *retval) 392{ 393 struct pci_vtblk_softc *sc = vsc; 394 void *ptr; 395 396 /* our caller has already verified offset and size */ 397 ptr = (uint8_t *)&sc->vbsc_cfg + offset; 398 memcpy(retval, ptr, size); 399 return (0); 400} 401 402struct pci_devemu pci_de_vblk = { 403 .pe_emu = "virtio-blk", 404 .pe_init = pci_vtblk_init, 405 .pe_barwrite = vi_pci_write, 406 .pe_barread = vi_pci_read 407}; 408PCI_EMUL_SET(pci_de_vblk); 409