| 1 | /* $NetBSD: viomb.c,v 1.7 2016/09/27 03:33:32 pgoyette Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 2010 Minoura Makoto. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #include <sys/cdefs.h> |
| 29 | __KERNEL_RCSID(0, "$NetBSD: viomb.c,v 1.7 2016/09/27 03:33:32 pgoyette Exp $" ); |
| 30 | |
| 31 | #include <sys/param.h> |
| 32 | #include <sys/systm.h> |
| 33 | #include <sys/kernel.h> |
| 34 | #include <sys/bus.h> |
| 35 | #include <sys/condvar.h> |
| 36 | #include <sys/device.h> |
| 37 | #include <sys/kthread.h> |
| 38 | #include <sys/mutex.h> |
| 39 | #include <sys/sysctl.h> |
| 40 | #include <uvm/uvm_page.h> |
| 41 | #include <sys/module.h> |
| 42 | |
| 43 | #include <dev/pci/pcidevs.h> |
| 44 | #include <dev/pci/pcireg.h> |
| 45 | #include <dev/pci/pcivar.h> |
| 46 | |
| 47 | #include <dev/pci/virtioreg.h> |
| 48 | #include <dev/pci/virtiovar.h> |
| 49 | |
| 50 | #include "ioconf.h" |
| 51 | |
| 52 | /* Configuration registers */ |
| 53 | #define VIRTIO_BALLOON_CONFIG_NUM_PAGES 0 /* 32bit */ |
| 54 | #define VIRTIO_BALLOON_CONFIG_ACTUAL 4 /* 32bit */ |
| 55 | |
| 56 | /* Feature bits */ |
| 57 | #define VIRTIO_BALLOON_F_MUST_TELL_HOST (1<<0) |
| 58 | #define VIRTIO_BALLOON_F_STATS_VQ (1<<1) |
| 59 | |
| 60 | #define VIRTIO_BALLOON_FLAG_BITS \ |
| 61 | VIRTIO_COMMON_FLAG_BITS \ |
| 62 | "\x02""STATS_VQ" \ |
| 63 | "\x01""MUST_TELL_HOST" |
| 64 | |
| 65 | #define PGS_PER_REQ (256) /* 1MB, 4KB/page */ |
| 66 | |
| 67 | CTASSERT((PAGE_SIZE) == (VIRTIO_PAGE_SIZE)); /* XXX */ |
| 68 | |
| 69 | struct balloon_req { |
| 70 | bus_dmamap_t bl_dmamap; |
| 71 | struct pglist bl_pglist; |
| 72 | int bl_nentries; |
| 73 | uint32_t bl_pages[PGS_PER_REQ]; |
| 74 | }; |
| 75 | |
| 76 | struct viomb_softc { |
| 77 | device_t sc_dev; |
| 78 | |
| 79 | struct virtio_softc *sc_virtio; |
| 80 | struct virtqueue sc_vq[2]; |
| 81 | |
| 82 | unsigned int sc_npages; |
| 83 | unsigned int sc_actual; |
| 84 | int sc_inflight; |
| 85 | struct balloon_req sc_req; |
| 86 | struct pglist sc_balloon_pages; |
| 87 | |
| 88 | int sc_inflate_done; |
| 89 | int sc_deflate_done; |
| 90 | |
| 91 | kcondvar_t sc_wait; |
| 92 | kmutex_t sc_waitlock; |
| 93 | }; |
| 94 | |
| 95 | static int balloon_initialized = 0; /* multiple balloon is not allowed */ |
| 96 | |
| 97 | static int viomb_match(device_t, cfdata_t, void *); |
| 98 | static void viomb_attach(device_t, device_t, void *); |
| 99 | static void viomb_read_config(struct viomb_softc *); |
| 100 | static int viomb_config_change(struct virtio_softc *); |
| 101 | static int inflate(struct viomb_softc *); |
| 102 | static int inflateq_done(struct virtqueue *); |
| 103 | static int inflate_done(struct viomb_softc *); |
| 104 | static int deflate(struct viomb_softc *); |
| 105 | static int deflateq_done(struct virtqueue *); |
| 106 | static int deflate_done(struct viomb_softc *); |
| 107 | static void viomb_thread(void *); |
| 108 | |
| 109 | CFATTACH_DECL_NEW(viomb, sizeof(struct viomb_softc), |
| 110 | viomb_match, viomb_attach, NULL, NULL); |
| 111 | |
| 112 | static int |
| 113 | viomb_match(device_t parent, cfdata_t match, void *aux) |
| 114 | { |
| 115 | struct virtio_softc *vsc = aux; |
| 116 | |
| 117 | if (vsc->sc_childdevid == PCI_PRODUCT_VIRTIO_BALLOON) |
| 118 | return 1; |
| 119 | |
| 120 | return 0; |
| 121 | } |
| 122 | |
| 123 | static void |
| 124 | viomb_attach(device_t parent, device_t self, void *aux) |
| 125 | { |
| 126 | struct viomb_softc *sc = device_private(self); |
| 127 | struct virtio_softc *vsc = device_private(parent); |
| 128 | const struct sysctlnode *node; |
| 129 | uint32_t features; |
| 130 | char buf[256]; |
| 131 | |
| 132 | if (vsc->sc_child != NULL) { |
| 133 | aprint_normal(": child already attached for %s; " |
| 134 | "something wrong...\n" , device_xname(parent)); |
| 135 | return; |
| 136 | } |
| 137 | if (balloon_initialized++) { |
| 138 | aprint_normal(": balloon already exists; something wrong...\n" ); |
| 139 | goto err_none; |
| 140 | } |
| 141 | |
| 142 | sc->sc_dev = self; |
| 143 | sc->sc_virtio = vsc; |
| 144 | |
| 145 | vsc->sc_child = self; |
| 146 | vsc->sc_ipl = IPL_VM; |
| 147 | vsc->sc_vqs = &sc->sc_vq[0]; |
| 148 | vsc->sc_nvqs = 2; |
| 149 | vsc->sc_config_change = viomb_config_change; |
| 150 | vsc->sc_intrhand = virtio_vq_intr; |
| 151 | vsc->sc_flags = 0; |
| 152 | |
| 153 | features = virtio_negotiate_features(vsc, |
| 154 | VIRTIO_CONFIG_DEVICE_FEATURES); |
| 155 | |
| 156 | snprintb(buf, sizeof(buf), VIRTIO_BALLOON_FLAG_BITS, features); |
| 157 | aprint_normal(": Features: %s\n" , buf); |
| 158 | if ((virtio_alloc_vq(vsc, &sc->sc_vq[0], 0, |
| 159 | sizeof(uint32_t)*PGS_PER_REQ, 1, |
| 160 | "inflate" ) != 0) || |
| 161 | (virtio_alloc_vq(vsc, &sc->sc_vq[1], 1, |
| 162 | sizeof(uint32_t)*PGS_PER_REQ, 1, |
| 163 | "deflate" ) != 0)) { |
| 164 | goto err_none; |
| 165 | } |
| 166 | sc->sc_vq[0].vq_done = inflateq_done; |
| 167 | sc->sc_vq[1].vq_done = deflateq_done; |
| 168 | |
| 169 | viomb_read_config(sc); |
| 170 | sc->sc_inflight = 0; |
| 171 | TAILQ_INIT(&sc->sc_balloon_pages); |
| 172 | |
| 173 | if (bus_dmamap_create(vsc->sc_dmat, sizeof(uint32_t)*PGS_PER_REQ, |
| 174 | 1, sizeof(uint32_t)*PGS_PER_REQ, 0, |
| 175 | BUS_DMA_NOWAIT, &sc->sc_req.bl_dmamap)) { |
| 176 | aprint_error_dev(sc->sc_dev, "dmamap creation failed.\n" ); |
| 177 | goto err_vq; |
| 178 | } |
| 179 | if (bus_dmamap_load(vsc->sc_dmat, sc->sc_req.bl_dmamap, |
| 180 | &sc->sc_req.bl_pages[0], |
| 181 | sizeof(uint32_t) * PGS_PER_REQ, |
| 182 | NULL, BUS_DMA_NOWAIT)) { |
| 183 | aprint_error_dev(sc->sc_dev, "dmamap load failed.\n" ); |
| 184 | goto err_dmamap; |
| 185 | } |
| 186 | |
| 187 | sc->sc_inflate_done = sc->sc_deflate_done = 0; |
| 188 | mutex_init(&sc->sc_waitlock, MUTEX_DEFAULT, IPL_VM); /* spin */ |
| 189 | cv_init(&sc->sc_wait, "balloon" ); |
| 190 | |
| 191 | if (kthread_create(PRI_IDLE, KTHREAD_MPSAFE, NULL, |
| 192 | viomb_thread, sc, NULL, "viomb" )) { |
| 193 | aprint_error_dev(sc->sc_dev, "cannot create kthread.\n" ); |
| 194 | goto err_mutex; |
| 195 | } |
| 196 | |
| 197 | sysctl_createv(NULL, 0, NULL, &node, 0, CTLTYPE_NODE, |
| 198 | "viomb" , SYSCTL_DESCR("VirtIO Balloon status" ), |
| 199 | NULL, 0, NULL, 0, |
| 200 | CTL_HW, CTL_CREATE, CTL_EOL); |
| 201 | sysctl_createv(NULL, 0, NULL, NULL, 0, CTLTYPE_INT, |
| 202 | "npages" , SYSCTL_DESCR("VirtIO Balloon npages value" ), |
| 203 | NULL, 0, &sc->sc_npages, 0, |
| 204 | CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL); |
| 205 | sysctl_createv(NULL, 0, NULL, NULL, 0, CTLTYPE_INT, |
| 206 | "actual" , SYSCTL_DESCR("VirtIO Balloon actual value" ), |
| 207 | NULL, 0, &sc->sc_actual, 0, |
| 208 | CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL); |
| 209 | return; |
| 210 | |
| 211 | err_mutex: |
| 212 | cv_destroy(&sc->sc_wait); |
| 213 | mutex_destroy(&sc->sc_waitlock); |
| 214 | err_dmamap: |
| 215 | bus_dmamap_destroy(vsc->sc_dmat, sc->sc_req.bl_dmamap); |
| 216 | err_vq: |
| 217 | virtio_free_vq(vsc, &sc->sc_vq[1]); |
| 218 | virtio_free_vq(vsc, &sc->sc_vq[0]); |
| 219 | err_none: |
| 220 | vsc->sc_child = (void*)1; |
| 221 | return; |
| 222 | } |
| 223 | |
| 224 | static void |
| 225 | viomb_read_config(struct viomb_softc *sc) |
| 226 | { |
| 227 | unsigned int reg; |
| 228 | |
| 229 | /* these values are explicitly specified as little-endian */ |
| 230 | reg = virtio_read_device_config_4(sc->sc_virtio, |
| 231 | VIRTIO_BALLOON_CONFIG_NUM_PAGES); |
| 232 | sc->sc_npages = le32toh(reg); |
| 233 | |
| 234 | reg = virtio_read_device_config_4(sc->sc_virtio, |
| 235 | VIRTIO_BALLOON_CONFIG_ACTUAL); |
| 236 | sc->sc_actual = le32toh(reg); |
| 237 | } |
| 238 | |
| 239 | /* |
| 240 | * Config change callback: wakeup the kthread. |
| 241 | */ |
| 242 | static int |
| 243 | viomb_config_change(struct virtio_softc *vsc) |
| 244 | { |
| 245 | struct viomb_softc *sc = device_private(vsc->sc_child); |
| 246 | unsigned int old; |
| 247 | |
| 248 | old = sc->sc_npages; |
| 249 | viomb_read_config(sc); |
| 250 | mutex_enter(&sc->sc_waitlock); |
| 251 | cv_signal(&sc->sc_wait); |
| 252 | mutex_exit(&sc->sc_waitlock); |
| 253 | if (sc->sc_npages > old) |
| 254 | printf("%s: inflating balloon from %u to %u.\n" , |
| 255 | device_xname(sc->sc_dev), old, sc->sc_npages); |
| 256 | else if (sc->sc_npages < old) |
| 257 | printf("%s: deflating balloon from %u to %u.\n" , |
| 258 | device_xname(sc->sc_dev), old, sc->sc_npages); |
| 259 | |
| 260 | return 1; |
| 261 | } |
| 262 | |
| 263 | /* |
| 264 | * Inflate: consume some amount of physical memory. |
| 265 | */ |
| 266 | static int |
| 267 | inflate(struct viomb_softc *sc) |
| 268 | { |
| 269 | struct virtio_softc *vsc = sc->sc_virtio; |
| 270 | int i, slot; |
| 271 | uint64_t nvpages, nhpages; |
| 272 | struct balloon_req *b; |
| 273 | struct vm_page *p; |
| 274 | struct virtqueue *vq = &sc->sc_vq[0]; |
| 275 | |
| 276 | if (sc->sc_inflight) |
| 277 | return 0; |
| 278 | nvpages = sc->sc_npages - sc->sc_actual; |
| 279 | if (nvpages > PGS_PER_REQ) |
| 280 | nvpages = PGS_PER_REQ; |
| 281 | nhpages = nvpages * VIRTIO_PAGE_SIZE / PAGE_SIZE; |
| 282 | |
| 283 | b = &sc->sc_req; |
| 284 | if (uvm_pglistalloc(nhpages*PAGE_SIZE, 0, UINT32_MAX*PAGE_SIZE, |
| 285 | 0, 0, &b->bl_pglist, nhpages, 1)) { |
| 286 | printf("%s: %" PRIu64 " pages of physical memory " |
| 287 | "could not be allocated, retrying...\n" , |
| 288 | device_xname(sc->sc_dev), nhpages); |
| 289 | return 1; /* sleep longer */ |
| 290 | } |
| 291 | |
| 292 | b->bl_nentries = nvpages; |
| 293 | i = 0; |
| 294 | TAILQ_FOREACH(p, &b->bl_pglist, pageq.queue) { |
| 295 | b->bl_pages[i++] = p->phys_addr / VIRTIO_PAGE_SIZE; |
| 296 | } |
| 297 | KASSERT(i == nvpages); |
| 298 | |
| 299 | if (virtio_enqueue_prep(vsc, vq, &slot) != 0) { |
| 300 | printf("%s: inflate enqueue failed.\n" , |
| 301 | device_xname(sc->sc_dev)); |
| 302 | uvm_pglistfree(&b->bl_pglist); |
| 303 | return 0; |
| 304 | } |
| 305 | if (virtio_enqueue_reserve(vsc, vq, slot, 1)) { |
| 306 | printf("%s: inflate enqueue failed.\n" , |
| 307 | device_xname(sc->sc_dev)); |
| 308 | uvm_pglistfree(&b->bl_pglist); |
| 309 | return 0; |
| 310 | } |
| 311 | bus_dmamap_sync(vsc->sc_dmat, b->bl_dmamap, 0, |
| 312 | sizeof(uint32_t)*nvpages, BUS_DMASYNC_PREWRITE); |
| 313 | virtio_enqueue(vsc, vq, slot, b->bl_dmamap, true); |
| 314 | virtio_enqueue_commit(vsc, vq, slot, true); |
| 315 | sc->sc_inflight += nvpages; |
| 316 | |
| 317 | return 0; |
| 318 | } |
| 319 | |
| 320 | static int |
| 321 | inflateq_done(struct virtqueue *vq) |
| 322 | { |
| 323 | struct virtio_softc *vsc = vq->vq_owner; |
| 324 | struct viomb_softc *sc = device_private(vsc->sc_child); |
| 325 | |
| 326 | mutex_enter(&sc->sc_waitlock); |
| 327 | sc->sc_inflate_done = 1; |
| 328 | cv_signal(&sc->sc_wait); |
| 329 | mutex_exit(&sc->sc_waitlock); |
| 330 | |
| 331 | return 1; |
| 332 | } |
| 333 | |
| 334 | static int |
| 335 | inflate_done(struct viomb_softc *sc) |
| 336 | { |
| 337 | struct virtio_softc *vsc = sc->sc_virtio; |
| 338 | struct virtqueue *vq = &sc->sc_vq[0]; |
| 339 | struct balloon_req *b; |
| 340 | int r, slot; |
| 341 | uint64_t nvpages; |
| 342 | struct vm_page *p; |
| 343 | |
| 344 | r = virtio_dequeue(vsc, vq, &slot, NULL); |
| 345 | if (r != 0) { |
| 346 | printf("%s: inflate dequeue failed, errno %d.\n" , |
| 347 | device_xname(sc->sc_dev), r); |
| 348 | return 1; |
| 349 | } |
| 350 | virtio_dequeue_commit(vsc, vq, slot); |
| 351 | |
| 352 | b = &sc->sc_req; |
| 353 | nvpages = b->bl_nentries; |
| 354 | bus_dmamap_sync(vsc->sc_dmat, b->bl_dmamap, |
| 355 | offsetof(struct balloon_req, bl_pages), |
| 356 | sizeof(uint32_t)*nvpages, |
| 357 | BUS_DMASYNC_POSTWRITE); |
| 358 | while (!TAILQ_EMPTY(&b->bl_pglist)) { |
| 359 | p = TAILQ_FIRST(&b->bl_pglist); |
| 360 | TAILQ_REMOVE(&b->bl_pglist, p, pageq.queue); |
| 361 | TAILQ_INSERT_TAIL(&sc->sc_balloon_pages, p, pageq.queue); |
| 362 | } |
| 363 | |
| 364 | sc->sc_inflight -= nvpages; |
| 365 | virtio_write_device_config_4(vsc, |
| 366 | VIRTIO_BALLOON_CONFIG_ACTUAL, |
| 367 | sc->sc_actual + nvpages); |
| 368 | viomb_read_config(sc); |
| 369 | |
| 370 | return 1; |
| 371 | } |
| 372 | |
| 373 | /* |
| 374 | * Deflate: free previously allocated memory. |
| 375 | */ |
| 376 | static int |
| 377 | deflate(struct viomb_softc *sc) |
| 378 | { |
| 379 | struct virtio_softc *vsc = sc->sc_virtio; |
| 380 | int i, slot; |
| 381 | uint64_t nvpages, nhpages; |
| 382 | struct balloon_req *b; |
| 383 | struct vm_page *p; |
| 384 | struct virtqueue *vq = &sc->sc_vq[1]; |
| 385 | |
| 386 | nvpages = (sc->sc_actual + sc->sc_inflight) - sc->sc_npages; |
| 387 | if (nvpages > PGS_PER_REQ) |
| 388 | nvpages = PGS_PER_REQ; |
| 389 | nhpages = nvpages * VIRTIO_PAGE_SIZE / PAGE_SIZE; |
| 390 | |
| 391 | b = &sc->sc_req; |
| 392 | |
| 393 | b->bl_nentries = nvpages; |
| 394 | TAILQ_INIT(&b->bl_pglist); |
| 395 | for (i = 0; i < nhpages; i++) { |
| 396 | p = TAILQ_FIRST(&sc->sc_balloon_pages); |
| 397 | if (p == NULL) |
| 398 | break; |
| 399 | TAILQ_REMOVE(&sc->sc_balloon_pages, p, pageq.queue); |
| 400 | TAILQ_INSERT_TAIL(&b->bl_pglist, p, pageq.queue); |
| 401 | b->bl_pages[i] = p->phys_addr / VIRTIO_PAGE_SIZE; |
| 402 | } |
| 403 | |
| 404 | if (virtio_enqueue_prep(vsc, vq, &slot) != 0) { |
| 405 | printf("%s: deflate enqueue failed.\n" , |
| 406 | device_xname(sc->sc_dev)); |
| 407 | TAILQ_FOREACH_REVERSE(p, &b->bl_pglist, pglist, pageq.queue) { |
| 408 | TAILQ_REMOVE(&b->bl_pglist, p, pageq.queue); |
| 409 | TAILQ_INSERT_HEAD(&sc->sc_balloon_pages, p, |
| 410 | pageq.queue); |
| 411 | } |
| 412 | return 0; |
| 413 | } |
| 414 | if (virtio_enqueue_reserve(vsc, vq, slot, 1) != 0) { |
| 415 | printf("%s: deflate enqueue failed.\n" , |
| 416 | device_xname(sc->sc_dev)); |
| 417 | TAILQ_FOREACH_REVERSE(p, &b->bl_pglist, pglist, pageq.queue) { |
| 418 | TAILQ_REMOVE(&b->bl_pglist, p, pageq.queue); |
| 419 | TAILQ_INSERT_HEAD(&sc->sc_balloon_pages, p, |
| 420 | pageq.queue); |
| 421 | } |
| 422 | return 0; |
| 423 | } |
| 424 | bus_dmamap_sync(vsc->sc_dmat, b->bl_dmamap, 0, |
| 425 | sizeof(uint32_t)*nvpages, BUS_DMASYNC_PREWRITE); |
| 426 | virtio_enqueue(vsc, vq, slot, b->bl_dmamap, true); |
| 427 | virtio_enqueue_commit(vsc, vq, slot, true); |
| 428 | sc->sc_inflight -= nvpages; |
| 429 | |
| 430 | if (!(vsc->sc_features & VIRTIO_BALLOON_F_MUST_TELL_HOST)) |
| 431 | uvm_pglistfree(&b->bl_pglist); |
| 432 | |
| 433 | return 0; |
| 434 | } |
| 435 | |
| 436 | static int |
| 437 | deflateq_done(struct virtqueue *vq) |
| 438 | { |
| 439 | struct virtio_softc *vsc = vq->vq_owner; |
| 440 | struct viomb_softc *sc = device_private(vsc->sc_child); |
| 441 | |
| 442 | mutex_enter(&sc->sc_waitlock); |
| 443 | sc->sc_deflate_done = 1; |
| 444 | cv_signal(&sc->sc_wait); |
| 445 | mutex_exit(&sc->sc_waitlock); |
| 446 | |
| 447 | return 1; |
| 448 | } |
| 449 | |
| 450 | static int |
| 451 | deflate_done(struct viomb_softc *sc) |
| 452 | { |
| 453 | struct virtio_softc *vsc = sc->sc_virtio; |
| 454 | struct virtqueue *vq = &sc->sc_vq[1]; |
| 455 | struct balloon_req *b; |
| 456 | int r, slot; |
| 457 | uint64_t nvpages; |
| 458 | |
| 459 | r = virtio_dequeue(vsc, vq, &slot, NULL); |
| 460 | if (r != 0) { |
| 461 | printf("%s: deflate dequeue failed, errno %d\n" , |
| 462 | device_xname(sc->sc_dev), r); |
| 463 | return 1; |
| 464 | } |
| 465 | virtio_dequeue_commit(vsc, vq, slot); |
| 466 | |
| 467 | b = &sc->sc_req; |
| 468 | nvpages = b->bl_nentries; |
| 469 | bus_dmamap_sync(vsc->sc_dmat, b->bl_dmamap, |
| 470 | offsetof(struct balloon_req, bl_pages), |
| 471 | sizeof(uint32_t)*nvpages, |
| 472 | BUS_DMASYNC_POSTWRITE); |
| 473 | |
| 474 | if (vsc->sc_features & VIRTIO_BALLOON_F_MUST_TELL_HOST) |
| 475 | uvm_pglistfree(&b->bl_pglist); |
| 476 | |
| 477 | sc->sc_inflight += nvpages; |
| 478 | virtio_write_device_config_4(vsc, |
| 479 | VIRTIO_BALLOON_CONFIG_ACTUAL, |
| 480 | sc->sc_actual - nvpages); |
| 481 | viomb_read_config(sc); |
| 482 | |
| 483 | return 1; |
| 484 | } |
| 485 | |
| 486 | /* |
| 487 | * Kthread: sleeps, eventually inflate and deflate. |
| 488 | */ |
| 489 | static void |
| 490 | viomb_thread(void *arg) |
| 491 | { |
| 492 | struct viomb_softc *sc = arg; |
| 493 | int sleeptime, r; |
| 494 | |
| 495 | for ( ; ; ) { |
| 496 | sleeptime = 30000; |
| 497 | if (sc->sc_npages > sc->sc_actual + sc->sc_inflight) { |
| 498 | if (sc->sc_inflight == 0) { |
| 499 | r = inflate(sc); |
| 500 | if (r != 0) |
| 501 | sleeptime = 10000; |
| 502 | else |
| 503 | sleeptime = 1000; |
| 504 | } else |
| 505 | sleeptime = 100; |
| 506 | } else if (sc->sc_npages < sc->sc_actual + sc->sc_inflight) { |
| 507 | if (sc->sc_inflight == 0) |
| 508 | r = deflate(sc); |
| 509 | sleeptime = 100; |
| 510 | } |
| 511 | |
| 512 | again: |
| 513 | mutex_enter(&sc->sc_waitlock); |
| 514 | if (sc->sc_inflate_done) { |
| 515 | sc->sc_inflate_done = 0; |
| 516 | mutex_exit(&sc->sc_waitlock); |
| 517 | inflate_done(sc); |
| 518 | goto again; |
| 519 | } |
| 520 | if (sc->sc_deflate_done) { |
| 521 | sc->sc_deflate_done = 0; |
| 522 | mutex_exit(&sc->sc_waitlock); |
| 523 | deflate_done(sc); |
| 524 | goto again; |
| 525 | } |
| 526 | cv_timedwait(&sc->sc_wait, &sc->sc_waitlock, |
| 527 | mstohz(sleeptime)); |
| 528 | mutex_exit(&sc->sc_waitlock); |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | MODULE(MODULE_CLASS_DRIVER, viomb, "virtio" ); |
| 533 | |
| 534 | #ifdef _MODULE |
| 535 | #include "ioconf.c" |
| 536 | #endif |
| 537 | |
| 538 | static int |
| 539 | viomb_modcmd(modcmd_t cmd, void *opaque) |
| 540 | { |
| 541 | int error = 0; |
| 542 | |
| 543 | #ifdef _MODULE |
| 544 | switch (cmd) { |
| 545 | case MODULE_CMD_INIT: |
| 546 | error = config_init_component(cfdriver_ioconf_viomb, |
| 547 | cfattach_ioconf_viomb, cfdata_ioconf_viomb); |
| 548 | break; |
| 549 | case MODULE_CMD_FINI: |
| 550 | error = config_fini_component(cfdriver_ioconf_viomb, |
| 551 | cfattach_ioconf_viomb, cfdata_ioconf_viomb); |
| 552 | break; |
| 553 | default: |
| 554 | error = ENOTTY; |
| 555 | break; |
| 556 | } |
| 557 | #endif |
| 558 | |
| 559 | return error; |
| 560 | } |
| 561 | |