| 1 | /* |
| 2 | * (MPSAFE) |
| 3 | * |
| 4 | * Copyright (c) 2006 The DragonFly Project. All rights reserved. |
| 5 | * |
| 6 | * This code is derived from software contributed to The DragonFly Project |
| 7 | * by Matthew Dillon <dillon@backplane.com> |
| 8 | * |
| 9 | * Redistribution and use in source and binary forms, with or without |
| 10 | * modification, are permitted provided that the following conditions |
| 11 | * are met: |
| 12 | * |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in |
| 17 | * the documentation and/or other materials provided with the |
| 18 | * distribution. |
| 19 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 20 | * contributors may be used to endorse or promote products derived |
| 21 | * from this software without specific, prior written permission. |
| 22 | * |
| 23 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 24 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 25 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 26 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 27 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 28 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 29 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 30 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 31 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 32 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 33 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 34 | * SUCH DAMAGE. |
| 35 | */ |
| 36 | |
| 37 | #include <sys/param.h> |
| 38 | #include <sys/kernel.h> |
| 39 | #include <sys/systm.h> |
| 40 | #include <sys/sysproto.h> |
| 41 | #include <sys/kern_syscall.h> |
| 42 | #include <sys/mman.h> |
| 43 | #include <sys/thread.h> |
| 44 | #include <sys/proc.h> |
| 45 | #include <sys/malloc.h> |
| 46 | #include <sys/sysctl.h> |
| 47 | #include <sys/vkernel.h> |
| 48 | #include <sys/vmspace.h> |
| 49 | |
| 50 | #include <vm/vm_extern.h> |
| 51 | #include <vm/pmap.h> |
| 52 | |
| 53 | #include <machine/vmparam.h> |
| 54 | |
| 55 | #include <sys/sysref2.h> |
| 56 | #include <sys/mplock2.h> |
| 57 | |
| 58 | static struct vmspace_entry *vkernel_find_vmspace(struct vkernel_proc *vkp, |
| 59 | void *id); |
| 60 | static void vmspace_entry_delete(struct vmspace_entry *ve, |
| 61 | struct vkernel_proc *vkp); |
| 62 | |
| 63 | static MALLOC_DEFINE(M_VKERNEL, "vkernel", "VKernel structures"); |
| 64 | |
| 65 | /* |
| 66 | * vmspace_create (void *id, int type, void *data) |
| 67 | * |
| 68 | * Create a VMSPACE under the control of the caller with the specified id. |
| 69 | * An id of NULL cannot be used. The type and data fields must currently |
| 70 | * be 0. |
| 71 | * |
| 72 | * The vmspace starts out completely empty. Memory may be mapped into the |
| 73 | * VMSPACE with vmspace_mmap() and MAP_VPAGETABLE section(s) controlled |
| 74 | * with vmspace_mcontrol(). |
| 75 | * |
| 76 | * No requirements. |
| 77 | */ |
| 78 | int |
| 79 | sys_vmspace_create(struct vmspace_create_args *uap) |
| 80 | { |
| 81 | struct vmspace_entry *ve; |
| 82 | struct vkernel_proc *vkp; |
| 83 | struct proc *p = curproc; |
| 84 | int error; |
| 85 | |
| 86 | if (vkernel_enable == 0) |
| 87 | return (EOPNOTSUPP); |
| 88 | |
| 89 | /* |
| 90 | * Create a virtual kernel side-structure for the process if one |
| 91 | * does not exist. |
| 92 | * |
| 93 | * Implement a simple resolution for SMP races. |
| 94 | */ |
| 95 | if ((vkp = p->p_vkernel) == NULL) { |
| 96 | vkp = kmalloc(sizeof(*vkp), M_VKERNEL, M_WAITOK|M_ZERO); |
| 97 | lwkt_gettoken(&proc_token); |
| 98 | if (p->p_vkernel == NULL) { |
| 99 | vkp->refs = 1; |
| 100 | lwkt_token_init(&vkp->token, "vkernel"); |
| 101 | RB_INIT(&vkp->root); |
| 102 | p->p_vkernel = vkp; |
| 103 | } else { |
| 104 | kfree(vkp, M_VKERNEL); |
| 105 | vkp = p->p_vkernel; |
| 106 | } |
| 107 | lwkt_reltoken(&proc_token); |
| 108 | } |
| 109 | |
| 110 | get_mplock(); |
| 111 | |
| 112 | /* |
| 113 | * Create a new VMSPACE, disallow conflicting ids |
| 114 | */ |
| 115 | ve = kmalloc(sizeof(struct vmspace_entry), M_VKERNEL, M_WAITOK|M_ZERO); |
| 116 | ve->vmspace = vmspace_alloc(VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); |
| 117 | ve->id = uap->id; |
| 118 | pmap_pinit2(vmspace_pmap(ve->vmspace)); |
| 119 | |
| 120 | lwkt_gettoken(&vkp->token); |
| 121 | if (RB_INSERT(vmspace_rb_tree, &vkp->root, ve)) { |
| 122 | sysref_put(&ve->vmspace->vm_sysref); |
| 123 | kfree(ve, M_VKERNEL); |
| 124 | error = EEXIST; |
| 125 | } else { |
| 126 | error = 0; |
| 127 | } |
| 128 | lwkt_reltoken(&vkp->token); |
| 129 | rel_mplock(); |
| 130 | return (error); |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * Destroy a VMSPACE given its identifier. |
| 135 | * |
| 136 | * No requirements. |
| 137 | */ |
| 138 | int |
| 139 | sys_vmspace_destroy(struct vmspace_destroy_args *uap) |
| 140 | { |
| 141 | struct vkernel_proc *vkp; |
| 142 | struct vmspace_entry *ve; |
| 143 | int error; |
| 144 | |
| 145 | get_mplock(); |
| 146 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 147 | error = EINVAL; |
| 148 | goto done3; |
| 149 | } |
| 150 | lwkt_gettoken(&vkp->token); |
| 151 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 152 | error = ENOENT; |
| 153 | goto done2; |
| 154 | } |
| 155 | if (ve->refs) { |
| 156 | error = EBUSY; |
| 157 | goto done2; |
| 158 | } |
| 159 | vmspace_entry_delete(ve, vkp); |
| 160 | error = 0; |
| 161 | done2: |
| 162 | lwkt_reltoken(&vkp->token); |
| 163 | done3: |
| 164 | rel_mplock(); |
| 165 | return(error); |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * vmspace_ctl (void *id, int cmd, struct trapframe *tframe, |
| 170 | * struct vextframe *vframe); |
| 171 | * |
| 172 | * Transfer control to a VMSPACE. Control is returned after the specified |
| 173 | * number of microseconds or if a page fault, signal, trap, or system call |
| 174 | * occurs. The context is updated as appropriate. |
| 175 | * |
| 176 | * No requirements. |
| 177 | */ |
| 178 | int |
| 179 | sys_vmspace_ctl(struct vmspace_ctl_args *uap) |
| 180 | { |
| 181 | struct vkernel_proc *vkp; |
| 182 | struct vkernel_lwp *vklp; |
| 183 | struct vmspace_entry *ve; |
| 184 | struct lwp *lp; |
| 185 | struct proc *p; |
| 186 | int framesz; |
| 187 | int error; |
| 188 | |
| 189 | lp = curthread->td_lwp; |
| 190 | p = lp->lwp_proc; |
| 191 | |
| 192 | if ((vkp = p->p_vkernel) == NULL) |
| 193 | return (EINVAL); |
| 194 | |
| 195 | get_mplock(); |
| 196 | lwkt_gettoken(&vkp->token); |
| 197 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 198 | error = ENOENT; |
| 199 | goto done; |
| 200 | } |
| 201 | |
| 202 | /* |
| 203 | * Signal mailbox interlock |
| 204 | */ |
| 205 | if (p->p_flag & P_MAILBOX) { |
| 206 | p->p_flag &= ~P_MAILBOX; |
| 207 | error = EINTR; |
| 208 | goto done; |
| 209 | } |
| 210 | |
| 211 | switch(uap->cmd) { |
| 212 | case VMSPACE_CTL_RUN: |
| 213 | /* |
| 214 | * Save the caller's register context, swap VM spaces, and |
| 215 | * install the passed register context. Return with |
| 216 | * EJUSTRETURN so the syscall code doesn't adjust the context. |
| 217 | */ |
| 218 | atomic_add_int(&ve->refs, 1); |
| 219 | framesz = sizeof(struct trapframe); |
| 220 | if ((vklp = lp->lwp_vkernel) == NULL) { |
| 221 | vklp = kmalloc(sizeof(*vklp), M_VKERNEL, |
| 222 | M_WAITOK|M_ZERO); |
| 223 | lp->lwp_vkernel = vklp; |
| 224 | } |
| 225 | vklp->user_trapframe = uap->tframe; |
| 226 | vklp->user_vextframe = uap->vframe; |
| 227 | bcopy(uap->sysmsg_frame, &vklp->save_trapframe, framesz); |
| 228 | bcopy(&curthread->td_tls, &vklp->save_vextframe.vx_tls, |
| 229 | sizeof(vklp->save_vextframe.vx_tls)); |
| 230 | error = copyin(uap->tframe, uap->sysmsg_frame, framesz); |
| 231 | if (error == 0) { |
| 232 | error = copyin(&uap->vframe->vx_tls, |
| 233 | &curthread->td_tls, |
| 234 | sizeof(struct savetls)); |
| 235 | } |
| 236 | if (error == 0) |
| 237 | error = cpu_sanitize_frame(uap->sysmsg_frame); |
| 238 | if (error == 0) |
| 239 | error = cpu_sanitize_tls(&curthread->td_tls); |
| 240 | if (error) { |
| 241 | bcopy(&vklp->save_trapframe, uap->sysmsg_frame, |
| 242 | framesz); |
| 243 | bcopy(&vklp->save_vextframe.vx_tls, &curthread->td_tls, |
| 244 | sizeof(vklp->save_vextframe.vx_tls)); |
| 245 | set_user_TLS(); |
| 246 | atomic_subtract_int(&ve->refs, 1); |
| 247 | } else { |
| 248 | vklp->ve = ve; |
| 249 | pmap_setlwpvm(lp, ve->vmspace); |
| 250 | set_user_TLS(); |
| 251 | set_vkernel_fp(uap->sysmsg_frame); |
| 252 | error = EJUSTRETURN; |
| 253 | } |
| 254 | break; |
| 255 | default: |
| 256 | error = EOPNOTSUPP; |
| 257 | break; |
| 258 | } |
| 259 | done: |
| 260 | lwkt_reltoken(&vkp->token); |
| 261 | rel_mplock(); |
| 262 | return(error); |
| 263 | } |
| 264 | |
| 265 | /* |
| 266 | * vmspace_mmap(id, addr, len, prot, flags, fd, offset) |
| 267 | * |
| 268 | * map memory within a VMSPACE. This function is just like a normal mmap() |
| 269 | * but operates on the vmspace's memory map. Most callers use this to create |
| 270 | * a MAP_VPAGETABLE mapping. |
| 271 | * |
| 272 | * No requirements. |
| 273 | */ |
| 274 | int |
| 275 | sys_vmspace_mmap(struct vmspace_mmap_args *uap) |
| 276 | { |
| 277 | struct vkernel_proc *vkp; |
| 278 | struct vmspace_entry *ve; |
| 279 | int error; |
| 280 | |
| 281 | /* |
| 282 | * We hold the vmspace token to serialize calls to vkernel_find_vmspace |
| 283 | * and the vm token to serialize calls to kern_mmap. |
| 284 | */ |
| 285 | lwkt_gettoken(&vm_token); |
| 286 | lwkt_gettoken(&vmspace_token); |
| 287 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 288 | error = EINVAL; |
| 289 | goto done3; |
| 290 | } |
| 291 | |
| 292 | /* |
| 293 | * NOTE: kern_mmap() can block so we need to temporarily ref ve->refs. |
| 294 | */ |
| 295 | lwkt_gettoken(&vkp->token); |
| 296 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) != NULL) { |
| 297 | atomic_add_int(&ve->refs, 1); |
| 298 | error = kern_mmap(ve->vmspace, uap->addr, uap->len, |
| 299 | uap->prot, uap->flags, |
| 300 | uap->fd, uap->offset, &uap->sysmsg_resultp); |
| 301 | atomic_subtract_int(&ve->refs, 1); |
| 302 | } else { |
| 303 | error = ENOENT; |
| 304 | } |
| 305 | lwkt_reltoken(&vkp->token); |
| 306 | done3: |
| 307 | lwkt_reltoken(&vmspace_token); |
| 308 | lwkt_reltoken(&vm_token); |
| 309 | return (error); |
| 310 | } |
| 311 | |
| 312 | /* |
| 313 | * vmspace_munmap(id, addr, len) |
| 314 | * |
| 315 | * unmap memory within a VMSPACE. |
| 316 | * |
| 317 | * No requirements. |
| 318 | */ |
| 319 | int |
| 320 | sys_vmspace_munmap(struct vmspace_munmap_args *uap) |
| 321 | { |
| 322 | struct vkernel_proc *vkp; |
| 323 | struct vmspace_entry *ve; |
| 324 | vm_offset_t addr; |
| 325 | vm_offset_t tmpaddr; |
| 326 | vm_size_t size, pageoff; |
| 327 | vm_map_t map; |
| 328 | int error; |
| 329 | |
| 330 | get_mplock(); |
| 331 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 332 | error = EINVAL; |
| 333 | goto done3; |
| 334 | } |
| 335 | lwkt_gettoken(&vkp->token); |
| 336 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 337 | error = ENOENT; |
| 338 | goto done2; |
| 339 | } |
| 340 | |
| 341 | /* |
| 342 | * NOTE: kern_munmap() can block so we need to temporarily |
| 343 | * ref ve->refs. |
| 344 | */ |
| 345 | atomic_add_int(&ve->refs, 1); |
| 346 | |
| 347 | /* |
| 348 | * Copied from sys_munmap() |
| 349 | */ |
| 350 | addr = (vm_offset_t)uap->addr; |
| 351 | size = uap->len; |
| 352 | |
| 353 | pageoff = (addr & PAGE_MASK); |
| 354 | addr -= pageoff; |
| 355 | size += pageoff; |
| 356 | size = (vm_size_t)round_page(size); |
| 357 | if (size < uap->len) { /* wrap */ |
| 358 | error = EINVAL; |
| 359 | goto done1; |
| 360 | } |
| 361 | tmpaddr = addr + size; /* workaround gcc4 opt */ |
| 362 | if (tmpaddr < addr) { /* wrap */ |
| 363 | error = EINVAL; |
| 364 | goto done1; |
| 365 | } |
| 366 | if (size == 0) { |
| 367 | error = 0; |
| 368 | goto done1; |
| 369 | } |
| 370 | |
| 371 | if (VM_MAX_USER_ADDRESS > 0 && tmpaddr > VM_MAX_USER_ADDRESS) { |
| 372 | error = EINVAL; |
| 373 | goto done1; |
| 374 | } |
| 375 | if (VM_MIN_USER_ADDRESS > 0 && addr < VM_MIN_USER_ADDRESS) { |
| 376 | error = EINVAL; |
| 377 | goto done1; |
| 378 | } |
| 379 | map = &ve->vmspace->vm_map; |
| 380 | if (!vm_map_check_protection(map, addr, tmpaddr, VM_PROT_NONE, FALSE)) { |
| 381 | error = EINVAL; |
| 382 | goto done1; |
| 383 | } |
| 384 | vm_map_remove(map, addr, addr + size); |
| 385 | error = 0; |
| 386 | done1: |
| 387 | atomic_subtract_int(&ve->refs, 1); |
| 388 | done2: |
| 389 | lwkt_reltoken(&vkp->token); |
| 390 | done3: |
| 391 | rel_mplock(); |
| 392 | return (error); |
| 393 | } |
| 394 | |
| 395 | /* |
| 396 | * vmspace_pread(id, buf, nbyte, flags, offset) |
| 397 | * |
| 398 | * Read data from a vmspace. The number of bytes read is returned or |
| 399 | * -1 if an unrecoverable error occured. If the number of bytes read is |
| 400 | * less then the request size, a page fault occured in the VMSPACE which |
| 401 | * the caller must resolve in order to proceed. |
| 402 | * |
| 403 | * (not implemented yet) |
| 404 | * No requirements. |
| 405 | */ |
| 406 | int |
| 407 | sys_vmspace_pread(struct vmspace_pread_args *uap) |
| 408 | { |
| 409 | struct vkernel_proc *vkp; |
| 410 | struct vmspace_entry *ve; |
| 411 | int error; |
| 412 | |
| 413 | get_mplock(); |
| 414 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 415 | error = EINVAL; |
| 416 | goto done3; |
| 417 | } |
| 418 | lwkt_gettoken(&vkp->token); |
| 419 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 420 | error = ENOENT; |
| 421 | goto done2; |
| 422 | } |
| 423 | error = EINVAL; |
| 424 | done2: |
| 425 | lwkt_reltoken(&vkp->token); |
| 426 | done3: |
| 427 | rel_mplock(); |
| 428 | return (error); |
| 429 | } |
| 430 | |
| 431 | /* |
| 432 | * vmspace_pwrite(id, buf, nbyte, flags, offset) |
| 433 | * |
| 434 | * Write data to a vmspace. The number of bytes written is returned or |
| 435 | * -1 if an unrecoverable error occured. If the number of bytes written is |
| 436 | * less then the request size, a page fault occured in the VMSPACE which |
| 437 | * the caller must resolve in order to proceed. |
| 438 | * |
| 439 | * (not implemented yet) |
| 440 | * No requirements. |
| 441 | */ |
| 442 | int |
| 443 | sys_vmspace_pwrite(struct vmspace_pwrite_args *uap) |
| 444 | { |
| 445 | struct vkernel_proc *vkp; |
| 446 | struct vmspace_entry *ve; |
| 447 | int error; |
| 448 | |
| 449 | get_mplock(); |
| 450 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 451 | error = EINVAL; |
| 452 | goto done3; |
| 453 | } |
| 454 | lwkt_gettoken(&vkp->token); |
| 455 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 456 | error = ENOENT; |
| 457 | goto done2; |
| 458 | } |
| 459 | error = EINVAL; |
| 460 | done2: |
| 461 | lwkt_reltoken(&vkp->token); |
| 462 | done3: |
| 463 | rel_mplock(); |
| 464 | return (error); |
| 465 | } |
| 466 | |
| 467 | /* |
| 468 | * vmspace_mcontrol(id, addr, len, behav, value) |
| 469 | * |
| 470 | * madvise/mcontrol support for a vmspace. |
| 471 | * |
| 472 | * No requirements. |
| 473 | */ |
| 474 | int |
| 475 | sys_vmspace_mcontrol(struct vmspace_mcontrol_args *uap) |
| 476 | { |
| 477 | struct vkernel_proc *vkp; |
| 478 | struct vmspace_entry *ve; |
| 479 | vm_offset_t start, end; |
| 480 | vm_offset_t tmpaddr = (vm_offset_t)uap->addr + uap->len; |
| 481 | int error; |
| 482 | |
| 483 | get_mplock(); |
| 484 | if ((vkp = curproc->p_vkernel) == NULL) { |
| 485 | error = EINVAL; |
| 486 | goto done3; |
| 487 | } |
| 488 | lwkt_gettoken(&vkp->token); |
| 489 | if ((ve = vkernel_find_vmspace(vkp, uap->id)) == NULL) { |
| 490 | error = ENOENT; |
| 491 | goto done2; |
| 492 | } |
| 493 | |
| 494 | /* |
| 495 | * NOTE: kern_madvise() can block so we need to temporarily |
| 496 | * ref ve->refs. |
| 497 | */ |
| 498 | atomic_add_int(&ve->refs, 1); |
| 499 | |
| 500 | /* |
| 501 | * This code is basically copied from sys_mcontrol() |
| 502 | */ |
| 503 | if (uap->behav < 0 || uap->behav > MADV_CONTROL_END) { |
| 504 | error = EINVAL; |
| 505 | goto done1; |
| 506 | } |
| 507 | |
| 508 | if (tmpaddr < (vm_offset_t)uap->addr) { |
| 509 | error = EINVAL; |
| 510 | goto done1; |
| 511 | } |
| 512 | if (VM_MAX_USER_ADDRESS > 0 && tmpaddr > VM_MAX_USER_ADDRESS) { |
| 513 | error = EINVAL; |
| 514 | goto done1; |
| 515 | } |
| 516 | if (VM_MIN_USER_ADDRESS > 0 && uap->addr < VM_MIN_USER_ADDRESS) { |
| 517 | error = EINVAL; |
| 518 | goto done1; |
| 519 | } |
| 520 | |
| 521 | start = trunc_page((vm_offset_t) uap->addr); |
| 522 | end = round_page(tmpaddr); |
| 523 | |
| 524 | error = vm_map_madvise(&ve->vmspace->vm_map, start, end, |
| 525 | uap->behav, uap->value); |
| 526 | done1: |
| 527 | atomic_subtract_int(&ve->refs, 1); |
| 528 | done2: |
| 529 | lwkt_reltoken(&vkp->token); |
| 530 | done3: |
| 531 | rel_mplock(); |
| 532 | return (error); |
| 533 | } |
| 534 | |
| 535 | /* |
| 536 | * Red black tree functions |
| 537 | */ |
| 538 | static int rb_vmspace_compare(struct vmspace_entry *, struct vmspace_entry *); |
| 539 | RB_GENERATE(vmspace_rb_tree, vmspace_entry, rb_entry, rb_vmspace_compare); |
| 540 | |
| 541 | /* |
| 542 | * a->start is address, and the only field has to be initialized. |
| 543 | * The caller must hold vkp->token. |
| 544 | * |
| 545 | * The caller must hold vkp->token. |
| 546 | */ |
| 547 | static int |
| 548 | rb_vmspace_compare(struct vmspace_entry *a, struct vmspace_entry *b) |
| 549 | { |
| 550 | if ((char *)a->id < (char *)b->id) |
| 551 | return(-1); |
| 552 | else if ((char *)a->id > (char *)b->id) |
| 553 | return(1); |
| 554 | return(0); |
| 555 | } |
| 556 | |
| 557 | /* |
| 558 | * The caller must hold vkp->token. |
| 559 | */ |
| 560 | static |
| 561 | int |
| 562 | rb_vmspace_delete(struct vmspace_entry *ve, void *data) |
| 563 | { |
| 564 | struct vkernel_proc *vkp = data; |
| 565 | |
| 566 | KKASSERT(ve->refs == 0); |
| 567 | vmspace_entry_delete(ve, vkp); |
| 568 | return(0); |
| 569 | } |
| 570 | |
| 571 | /* |
| 572 | * Remove a vmspace_entry from the RB tree and destroy it. We have to clean |
| 573 | * up the pmap, the vm_map, then destroy the vmspace. |
| 574 | * |
| 575 | * This function must remove the ve immediately before it might potentially |
| 576 | * block. |
| 577 | * |
| 578 | * The caller must hold vkp->token. |
| 579 | */ |
| 580 | static |
| 581 | void |
| 582 | vmspace_entry_delete(struct vmspace_entry *ve, struct vkernel_proc *vkp) |
| 583 | { |
| 584 | RB_REMOVE(vmspace_rb_tree, &vkp->root, ve); |
| 585 | |
| 586 | pmap_remove_pages(vmspace_pmap(ve->vmspace), |
| 587 | VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); |
| 588 | vm_map_remove(&ve->vmspace->vm_map, |
| 589 | VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); |
| 590 | sysref_put(&ve->vmspace->vm_sysref); |
| 591 | kfree(ve, M_VKERNEL); |
| 592 | } |
| 593 | |
| 594 | /* |
| 595 | * Locate the ve for (id), return the ve or NULL. If found this function |
| 596 | * will bump ve->refs which prevents the ve from being immediately destroyed |
| 597 | * (but it can still be removed). |
| 598 | * |
| 599 | * The caller must hold vkp->token. |
| 600 | */ |
| 601 | static |
| 602 | struct vmspace_entry * |
| 603 | vkernel_find_vmspace(struct vkernel_proc *vkp, void *id) |
| 604 | { |
| 605 | struct vmspace_entry *ve; |
| 606 | struct vmspace_entry key; |
| 607 | |
| 608 | key.id = id; |
| 609 | ve = RB_FIND(vmspace_rb_tree, &vkp->root, &key); |
| 610 | return (ve); |
| 611 | } |
| 612 | |
| 613 | /* |
| 614 | * Manage vkernel refs, used by the kernel when fork()ing or exit()ing |
| 615 | * a vkernel process. |
| 616 | * |
| 617 | * No requirements. |
| 618 | */ |
| 619 | void |
| 620 | vkernel_inherit(struct proc *p1, struct proc *p2) |
| 621 | { |
| 622 | struct vkernel_proc *vkp; |
| 623 | |
| 624 | vkp = p1->p_vkernel; |
| 625 | KKASSERT(vkp->refs > 0); |
| 626 | atomic_add_int(&vkp->refs, 1); |
| 627 | p2->p_vkernel = vkp; |
| 628 | } |
| 629 | |
| 630 | /* |
| 631 | * No requirements. |
| 632 | */ |
| 633 | void |
| 634 | vkernel_exit(struct proc *p) |
| 635 | { |
| 636 | struct vkernel_proc *vkp; |
| 637 | struct lwp *lp; |
| 638 | |
| 639 | vkp = p->p_vkernel; |
| 640 | |
| 641 | /* |
| 642 | * Restore the original VM context if we are killed while running |
| 643 | * a different one. |
| 644 | * |
| 645 | * This isn't supposed to happen. What is supposed to happen is |
| 646 | * that the process should enter vkernel_trap() before the handling |
| 647 | * the signal. |
| 648 | */ |
| 649 | RB_FOREACH(lp, lwp_rb_tree, &p->p_lwp_tree) { |
| 650 | vkernel_lwp_exit(lp); |
| 651 | } |
| 652 | |
| 653 | /* |
| 654 | * Dereference the common area |
| 655 | */ |
| 656 | p->p_vkernel = NULL; |
| 657 | KKASSERT(vkp->refs > 0); |
| 658 | |
| 659 | if (atomic_fetchadd_int(&vkp->refs, -1) == 1) { |
| 660 | lwkt_gettoken(&vkp->token); |
| 661 | RB_SCAN(vmspace_rb_tree, &vkp->root, NULL, |
| 662 | rb_vmspace_delete, vkp); |
| 663 | lwkt_reltoken(&vkp->token); |
| 664 | kfree(vkp, M_VKERNEL); |
| 665 | } |
| 666 | } |
| 667 | |
| 668 | /* |
| 669 | * No requirements. |
| 670 | */ |
| 671 | void |
| 672 | vkernel_lwp_exit(struct lwp *lp) |
| 673 | { |
| 674 | struct vkernel_lwp *vklp; |
| 675 | struct vmspace_entry *ve; |
| 676 | |
| 677 | if ((vklp = lp->lwp_vkernel) != NULL) { |
| 678 | if ((ve = vklp->ve) != NULL) { |
| 679 | kprintf("Warning, pid %d killed with " |
| 680 | "active VC!\n", lp->lwp_proc->p_pid); |
| 681 | pmap_setlwpvm(lp, lp->lwp_proc->p_vmspace); |
| 682 | vklp->ve = NULL; |
| 683 | KKASSERT(ve->refs > 0); |
| 684 | atomic_subtract_int(&ve->refs, 1); |
| 685 | } |
| 686 | lp->lwp_vkernel = NULL; |
| 687 | kfree(vklp, M_VKERNEL); |
| 688 | } |
| 689 | } |
| 690 | |
| 691 | /* |
| 692 | * A VM space under virtual kernel control trapped out or made a system call |
| 693 | * or otherwise needs to return control to the virtual kernel context. |
| 694 | * |
| 695 | * No requirements. |
| 696 | */ |
| 697 | void |
| 698 | vkernel_trap(struct lwp *lp, struct trapframe *frame) |
| 699 | { |
| 700 | struct proc *p = lp->lwp_proc; |
| 701 | struct vmspace_entry *ve; |
| 702 | struct vkernel_lwp *vklp; |
| 703 | int error; |
| 704 | |
| 705 | /* |
| 706 | * Which vmspace entry was running? |
| 707 | */ |
| 708 | vklp = lp->lwp_vkernel; |
| 709 | KKASSERT(vklp); |
| 710 | ve = vklp->ve; |
| 711 | KKASSERT(ve != NULL); |
| 712 | |
| 713 | /* |
| 714 | * Switch the LWP vmspace back to the virtual kernel's VM space. |
| 715 | */ |
| 716 | vklp->ve = NULL; |
| 717 | pmap_setlwpvm(lp, p->p_vmspace); |
| 718 | KKASSERT(ve->refs > 0); |
| 719 | atomic_subtract_int(&ve->refs, 1); |
| 720 | /* ve is invalid once we kill our ref */ |
| 721 | |
| 722 | /* |
| 723 | * Copy the emulated process frame to the virtual kernel process. |
| 724 | * The emulated process cannot change TLS descriptors so don't |
| 725 | * bother saving them, we already have a copy. |
| 726 | * |
| 727 | * Restore the virtual kernel's saved context so the virtual kernel |
| 728 | * process can resume. |
| 729 | */ |
| 730 | error = copyout(frame, vklp->user_trapframe, sizeof(*frame)); |
| 731 | bcopy(&vklp->save_trapframe, frame, sizeof(*frame)); |
| 732 | bcopy(&vklp->save_vextframe.vx_tls, &curthread->td_tls, |
| 733 | sizeof(vklp->save_vextframe.vx_tls)); |
| 734 | set_user_TLS(); |
| 735 | cpu_vkernel_trap(frame, error); |
| 736 | } |