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 #include <md5.h> 50 51 #include "bhyverun.h" 52 #include "pci_emul.h" 53 #include "virtio.h" 54 55 #define VTBLK_RINGSZ 64 56 57 #define VTBLK_MAXSEGS 32 58 59 #define VTBLK_S_OK 0 60 #define VTBLK_S_IOERR 1 61 #define VTBLK_S_UNSUPP 2 62 63 #define VTBLK_BLK_ID_BYTES 20 64 65 /* Capability bits */ 66 #define VTBLK_F_SEG_MAX (1 << 2) /* Maximum request segments */ 67 #define VTBLK_F_BLK_SIZE (1 << 6) /* cfg block size valid */ 68 69 /* 70 * Host capabilities 71 */ 72 #define VTBLK_S_HOSTCAPS \ 73 ( VTBLK_F_SEG_MAX | \ 74 VTBLK_F_BLK_SIZE | \ 75 VIRTIO_RING_F_INDIRECT_DESC ) /* indirect descriptors */ 76 77 /* 78 * Config space "registers" 79 */ 80 struct vtblk_config { 81 uint64_t vbc_capacity; 82 uint32_t vbc_size_max; 83 uint32_t vbc_seg_max; 84 uint16_t vbc_geom_c; 85 uint8_t vbc_geom_h; 86 uint8_t vbc_geom_s; 87 uint32_t vbc_blk_size; 88 uint32_t vbc_sectors_max; 89 } __packed; 90 91 /* 92 * Fixed-size block header 93 */ 94 struct virtio_blk_hdr { 95 #define VBH_OP_READ 0 96 #define VBH_OP_WRITE 1 97 #define VBH_OP_IDENT 8 98 #define VBH_FLAG_BARRIER 0x80000000 /* OR'ed into vbh_type */ 99 uint32_t vbh_type; 100 uint32_t vbh_ioprio; 101 uint64_t vbh_sector; 102 } __packed; 103 104 /* 105 * Debug printf 106 */ 107 static int pci_vtblk_debug; 108 #define DPRINTF(params) if (pci_vtblk_debug) printf params 109 #define WPRINTF(params) printf params 110 111 /* 112 * Per-device softc 113 */ 114 struct pci_vtblk_softc { 115 struct virtio_softc vbsc_vs; 116 pthread_mutex_t vsc_mtx; 117 struct vqueue_info vbsc_vq; 118 int vbsc_fd; 119 struct vtblk_config vbsc_cfg; 120 char vbsc_ident[VTBLK_BLK_ID_BYTES]; 121 }; 122 123 static void pci_vtblk_reset(void *); 124 static void pci_vtblk_notify(void *, struct vqueue_info *); 125 static int pci_vtblk_cfgread(void *, int, int, uint32_t *); 126 static int pci_vtblk_cfgwrite(void *, int, int, uint32_t); 127 128 static struct virtio_consts vtblk_vi_consts = { 129 "vtblk", /* our name */ 130 1, /* we support 1 virtqueue */ 131 sizeof(struct vtblk_config), /* config reg size */ 132 pci_vtblk_reset, /* reset */ 133 pci_vtblk_notify, /* device-wide qnotify */ 134 pci_vtblk_cfgread, /* read PCI config */ 135 pci_vtblk_cfgwrite, /* write PCI config */ 136 VTBLK_S_HOSTCAPS, /* our capabilities */ 137 }; 138 139 static void 140 pci_vtblk_reset(void *vsc) 141 { 142 struct pci_vtblk_softc *sc = vsc; 143 144 DPRINTF(("vtblk: device reset requested !\n")); 145 vi_reset_dev(&sc->vbsc_vs); 146 } 147 148 static void 149 pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vqueue_info *vq) 150 { 151 struct virtio_blk_hdr *vbh; 152 uint8_t *status; 153 int i, n; 154 int err; 155 int iolen; 156 int writeop, type; 157 off_t offset; 158 struct iovec iov[VTBLK_MAXSEGS + 2]; 159 uint16_t flags[VTBLK_MAXSEGS + 2]; 160 161 n = vq_getchain(vq, iov, VTBLK_MAXSEGS + 2, flags); 162 163 /* 164 * The first descriptor will be the read-only fixed header, 165 * and the last is for status (hence +2 above and below). 166 * The remaining iov's are the actual data I/O vectors. 167 * 168 * XXX - note - this fails on crash dump, which does a 169 * VIRTIO_BLK_T_FLUSH with a zero transfer length 170 */ 171 assert(n >= 2 && n <= VTBLK_MAXSEGS + 2); 172 173 assert((flags[0] & VRING_DESC_F_WRITE) == 0); 174 assert(iov[0].iov_len == sizeof(struct virtio_blk_hdr)); 175 vbh = iov[0].iov_base; 176 177 status = iov[--n].iov_base; 178 assert(iov[n].iov_len == 1); 179 assert(flags[n] & VRING_DESC_F_WRITE); 180 181 /* 182 * XXX 183 * The guest should not be setting the BARRIER flag because 184 * we don't advertise the capability. 185 */ 186 type = vbh->vbh_type & ~VBH_FLAG_BARRIER; 187 writeop = (type == VBH_OP_WRITE); 188 189 offset = vbh->vbh_sector * DEV_BSIZE; 190 191 iolen = 0; 192 for (i = 1; i < n; i++) { 193 /* 194 * - write op implies read-only descriptor, 195 * - read/ident op implies write-only descriptor, 196 * therefore test the inverse of the descriptor bit 197 * to the op. 198 */ 199 assert(((flags[i] & VRING_DESC_F_WRITE) == 0) == writeop); 200 iolen += iov[i].iov_len; 201 } 202 203 DPRINTF(("virtio-block: %s op, %d bytes, %d segs, offset %ld\n\r", 204 writeop ? "write" : "read/ident", iolen, i - 1, offset)); 205 206 switch (type) { 207 case VBH_OP_WRITE: 208 err = pwritev(sc->vbsc_fd, iov + 1, i - 1, offset); 209 break; 210 case VBH_OP_READ: 211 err = preadv(sc->vbsc_fd, iov + 1, i - 1, offset); 212 break; 213 case VBH_OP_IDENT: 214 /* Assume a single buffer */ 215 strlcpy(iov[1].iov_base, sc->vbsc_ident, 216 MIN(iov[1].iov_len, sizeof(sc->vbsc_ident))); 217 err = 0; 218 break; 219 default: 220 err = -ENOSYS; 221 break; 222 } 223 224 /* convert errno into a virtio block error return */ 225 if (err < 0) { 226 if (err == -ENOSYS) 227 *status = VTBLK_S_UNSUPP; 228 else 229 *status = VTBLK_S_IOERR; 230 } else 231 *status = VTBLK_S_OK; 232 233 /* 234 * Return the descriptor back to the host. 235 * We wrote 1 byte (our status) to host. 236 */ 237 vq_relchain(vq, 1); 238 } 239 240 static void 241 pci_vtblk_notify(void *vsc, struct vqueue_info *vq) 242 { 243 struct pci_vtblk_softc *sc = vsc; 244 245 vq_startchains(vq); 246 while (vq_has_descs(vq)) 247 pci_vtblk_proc(sc, vq); 248 vq_endchains(vq, 1); /* Generate interrupt if appropriate. */ 249 } 250 251 static int 252 pci_vtblk_init(struct vmctx *ctx, struct pci_devinst *pi, char *opts) 253 { 254 struct stat sbuf; 255 MD5_CTX mdctx; 256 u_char digest[16]; 257 struct pci_vtblk_softc *sc; 258 off_t size; 259 int fd; 260 int sectsz; 261 262 if (opts == NULL) { 263 printf("virtio-block: backing device required\n"); 264 return (1); 265 } 266 267 /* 268 * The supplied backing file has to exist 269 */ 270 fd = open(opts, O_RDWR); 271 if (fd < 0) { 272 perror("Could not open backing file"); 273 return (1); 274 } 275 276 if (fstat(fd, &sbuf) < 0) { 277 perror("Could not stat backing file"); 278 close(fd); 279 return (1); 280 } 281 282 /* 283 * Deal with raw devices 284 */ 285 size = sbuf.st_size; 286 sectsz = DEV_BSIZE; 287 if (S_ISCHR(sbuf.st_mode)) { 288 if (ioctl(fd, DIOCGMEDIASIZE, &size) < 0 || 289 ioctl(fd, DIOCGSECTORSIZE, §sz)) { 290 perror("Could not fetch dev blk/sector size"); 291 close(fd); 292 return (1); 293 } 294 assert(size != 0); 295 assert(sectsz != 0); 296 } 297 298 sc = calloc(1, sizeof(struct pci_vtblk_softc)); 299 300 /* record fd of storage device/file */ 301 sc->vbsc_fd = fd; 302 303 pthread_mutex_init(&sc->vsc_mtx, NULL); 304 305 /* init virtio softc and virtqueues */ 306 vi_softc_linkup(&sc->vbsc_vs, &vtblk_vi_consts, sc, pi, &sc->vbsc_vq); 307 sc->vbsc_vs.vs_mtx = &sc->vsc_mtx; 308 309 sc->vbsc_vq.vq_qsize = VTBLK_RINGSZ; 310 /* sc->vbsc_vq.vq_notify = we have no per-queue notify */ 311 312 /* 313 * Create an identifier for the backing file. Use parts of the 314 * md5 sum of the filename 315 */ 316 MD5Init(&mdctx); 317 MD5Update(&mdctx, opts, strlen(opts)); 318 MD5Final(digest, &mdctx); 319 sprintf(sc->vbsc_ident, "BHYVE-%02X%02X-%02X%02X-%02X%02X", 320 digest[0], digest[1], digest[2], digest[3], digest[4], digest[5]); 321 322 /* setup virtio block config space */ 323 sc->vbsc_cfg.vbc_capacity = size / DEV_BSIZE; /* 512-byte units */ 324 sc->vbsc_cfg.vbc_seg_max = VTBLK_MAXSEGS; 325 sc->vbsc_cfg.vbc_blk_size = sectsz; 326 sc->vbsc_cfg.vbc_size_max = 0; /* not negotiated */ 327 sc->vbsc_cfg.vbc_geom_c = 0; /* no geometry */ 328 sc->vbsc_cfg.vbc_geom_h = 0; 329 sc->vbsc_cfg.vbc_geom_s = 0; 330 sc->vbsc_cfg.vbc_sectors_max = 0; 331 332 /* 333 * Should we move some of this into virtio.c? Could 334 * have the device, class, and subdev_0 as fields in 335 * the virtio constants structure. 336 */ 337 pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_BLOCK); 338 pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR); 339 pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE); 340 pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_TYPE_BLOCK); 341 342 pci_lintr_request(pi); 343 344 if (vi_intr_init(&sc->vbsc_vs, 1, fbsdrun_virtio_msix())) 345 return (1); 346 vi_set_io_bar(&sc->vbsc_vs, 0); 347 return (0); 348 } 349 350 static int 351 pci_vtblk_cfgwrite(void *vsc, int offset, int size, uint32_t value) 352 { 353 354 DPRINTF(("vtblk: write to readonly reg %d\n\r", offset)); 355 return (1); 356 } 357 358 static int 359 pci_vtblk_cfgread(void *vsc, int offset, int size, uint32_t *retval) 360 { 361 struct pci_vtblk_softc *sc = vsc; 362 void *ptr; 363 364 /* our caller has already verified offset and size */ 365 ptr = (uint8_t *)&sc->vbsc_cfg + offset; 366 memcpy(retval, ptr, size); 367 return (0); 368 } 369 370 struct pci_devemu pci_de_vblk = { 371 .pe_emu = "virtio-blk", 372 .pe_init = pci_vtblk_init, 373 .pe_barwrite = vi_pci_write, 374 .pe_barread = vi_pci_read 375 }; 376 PCI_EMUL_SET(pci_de_vblk); 377