vm_machdep.c revision 278614
1/*- 2 * Copyright (c) 1982, 1986 The Regents of the University of California. 3 * Copyright (c) 1989, 1990 William Jolitz 4 * Copyright (c) 1994 John Dyson 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department, and William Jolitz. 10 * 11 * Redistribution and use in source and binary :forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 */ 42 43#include <sys/cdefs.h> 44__FBSDID("$FreeBSD: stable/10/sys/arm/arm/vm_machdep.c 278614 2015-02-12 04:15:55Z ian $"); 45 46#include <sys/param.h> 47#include <sys/systm.h> 48#include <sys/kernel.h> 49#include <sys/malloc.h> 50#include <sys/mbuf.h> 51#include <sys/proc.h> 52#include <sys/socketvar.h> 53#include <sys/sf_buf.h> 54#include <sys/syscall.h> 55#include <sys/sysctl.h> 56#include <sys/sysent.h> 57#include <sys/unistd.h> 58#include <machine/cpu.h> 59#include <machine/frame.h> 60#include <machine/pcb.h> 61#include <machine/sysarch.h> 62#include <sys/lock.h> 63#include <sys/mutex.h> 64 65#include <vm/vm.h> 66#include <vm/pmap.h> 67#include <vm/vm_extern.h> 68#include <vm/vm_kern.h> 69#include <vm/vm_page.h> 70#include <vm/vm_map.h> 71#include <vm/vm_param.h> 72#include <vm/vm_pageout.h> 73#include <vm/uma.h> 74#include <vm/uma_int.h> 75 76#include <machine/md_var.h> 77#include <machine/vfp.h> 78 79/* 80 * struct switchframe and trapframe must both be a multiple of 8 81 * for correct stack alignment. 82 */ 83CTASSERT(sizeof(struct switchframe) == 48); 84CTASSERT(sizeof(struct trapframe) == 80); 85 86#ifndef NSFBUFS 87#define NSFBUFS (512 + maxusers * 16) 88#endif 89 90static int nsfbufs; 91static int nsfbufspeak; 92static int nsfbufsused; 93 94SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufs, CTLFLAG_RDTUN, &nsfbufs, 0, 95 "Maximum number of sendfile(2) sf_bufs available"); 96SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufspeak, CTLFLAG_RD, &nsfbufspeak, 0, 97 "Number of sendfile(2) sf_bufs at peak usage"); 98SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufsused, CTLFLAG_RD, &nsfbufsused, 0, 99 "Number of sendfile(2) sf_bufs in use"); 100 101static void sf_buf_init(void *arg); 102SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL); 103 104LIST_HEAD(sf_head, sf_buf); 105 106/* 107 * A hash table of active sendfile(2) buffers 108 */ 109static struct sf_head *sf_buf_active; 110static u_long sf_buf_hashmask; 111 112#define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask) 113 114static TAILQ_HEAD(, sf_buf) sf_buf_freelist; 115static u_int sf_buf_alloc_want; 116 117/* 118 * A lock used to synchronize access to the hash table and free list 119 */ 120static struct mtx sf_buf_lock; 121 122/* 123 * Finish a fork operation, with process p2 nearly set up. 124 * Copy and update the pcb, set up the stack so that the child 125 * ready to run and return to user mode. 126 */ 127void 128cpu_fork(register struct thread *td1, register struct proc *p2, 129 struct thread *td2, int flags) 130{ 131 struct pcb *pcb2; 132 struct trapframe *tf; 133 struct mdproc *mdp2; 134 135 if ((flags & RFPROC) == 0) 136 return; 137 138 /* Point the pcb to the top of the stack */ 139 pcb2 = (struct pcb *) 140 (td2->td_kstack + td2->td_kstack_pages * PAGE_SIZE) - 1; 141#ifdef __XSCALE__ 142#ifndef CPU_XSCALE_CORE3 143 pmap_use_minicache(td2->td_kstack, td2->td_kstack_pages * PAGE_SIZE); 144#endif 145#endif 146 td2->td_pcb = pcb2; 147 148 /* Clone td1's pcb */ 149 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2)); 150 151 /* Point to mdproc and then copy over td1's contents */ 152 mdp2 = &p2->p_md; 153 bcopy(&td1->td_proc->p_md, mdp2, sizeof(*mdp2)); 154 155 /* Point the frame to the stack in front of pcb and copy td1's frame */ 156 td2->td_frame = (struct trapframe *)pcb2 - 1; 157 *td2->td_frame = *td1->td_frame; 158 159 /* 160 * Create a new fresh stack for the new process. 161 * Copy the trap frame for the return to user mode as if from a 162 * syscall. This copies most of the user mode register values. 163 */ 164 pmap_set_pcb_pagedir(vmspace_pmap(p2->p_vmspace), pcb2); 165 pcb2->pcb_regs.sf_r4 = (register_t)fork_return; 166 pcb2->pcb_regs.sf_r5 = (register_t)td2; 167 pcb2->pcb_regs.sf_lr = (register_t)fork_trampoline; 168 pcb2->pcb_regs.sf_sp = STACKALIGN(td2->td_frame); 169 170 pcb2->pcb_vfpcpu = -1; 171 pcb2->pcb_vfpstate.fpscr = VFPSCR_DN | VFPSCR_FZ; 172 173 tf = td2->td_frame; 174 tf->tf_spsr &= ~PSR_C; 175 tf->tf_r0 = 0; 176 tf->tf_r1 = 0; 177 178 179 /* Setup to release spin count in fork_exit(). */ 180 td2->td_md.md_spinlock_count = 1; 181 td2->td_md.md_saved_cspr = PSR_SVC32_MODE;; 182#ifdef ARM_TP_ADDRESS 183 td2->td_md.md_tp = *(register_t *)ARM_TP_ADDRESS; 184#else 185 td2->td_md.md_tp = (register_t) get_tls(); 186#endif 187} 188 189void 190cpu_thread_swapin(struct thread *td) 191{ 192} 193 194void 195cpu_thread_swapout(struct thread *td) 196{ 197} 198 199/* 200 * Detatch mapped page and release resources back to the system. 201 */ 202void 203sf_buf_free(struct sf_buf *sf) 204{ 205 206 mtx_lock(&sf_buf_lock); 207 sf->ref_count--; 208 if (sf->ref_count == 0) { 209 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry); 210 nsfbufsused--; 211 pmap_kremove(sf->kva); 212 sf->m = NULL; 213 LIST_REMOVE(sf, list_entry); 214 if (sf_buf_alloc_want > 0) 215 wakeup(&sf_buf_freelist); 216 } 217 mtx_unlock(&sf_buf_lock); 218} 219 220/* 221 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-)) 222 */ 223static void 224sf_buf_init(void *arg) 225{ 226 struct sf_buf *sf_bufs; 227 vm_offset_t sf_base; 228 int i; 229 230 nsfbufs = NSFBUFS; 231 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs); 232 233 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask); 234 TAILQ_INIT(&sf_buf_freelist); 235 sf_base = kva_alloc(nsfbufs * PAGE_SIZE); 236 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP, 237 M_NOWAIT | M_ZERO); 238 for (i = 0; i < nsfbufs; i++) { 239 sf_bufs[i].kva = sf_base + i * PAGE_SIZE; 240 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry); 241 } 242 sf_buf_alloc_want = 0; 243 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF); 244} 245 246/* 247 * Get an sf_buf from the freelist. Will block if none are available. 248 */ 249struct sf_buf * 250sf_buf_alloc(struct vm_page *m, int flags) 251{ 252 struct sf_head *hash_list; 253 struct sf_buf *sf; 254 int error; 255 256 hash_list = &sf_buf_active[SF_BUF_HASH(m)]; 257 mtx_lock(&sf_buf_lock); 258 LIST_FOREACH(sf, hash_list, list_entry) { 259 if (sf->m == m) { 260 sf->ref_count++; 261 if (sf->ref_count == 1) { 262 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 263 nsfbufsused++; 264 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 265 } 266 goto done; 267 } 268 } 269 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) { 270 if (flags & SFB_NOWAIT) 271 goto done; 272 sf_buf_alloc_want++; 273 SFSTAT_INC(sf_allocwait); 274 error = msleep(&sf_buf_freelist, &sf_buf_lock, 275 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0); 276 sf_buf_alloc_want--; 277 278 279 /* 280 * If we got a signal, don't risk going back to sleep. 281 */ 282 if (error) 283 goto done; 284 } 285 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry); 286 if (sf->m != NULL) 287 LIST_REMOVE(sf, list_entry); 288 LIST_INSERT_HEAD(hash_list, sf, list_entry); 289 sf->ref_count = 1; 290 sf->m = m; 291 nsfbufsused++; 292 nsfbufspeak = imax(nsfbufspeak, nsfbufsused); 293 pmap_kenter(sf->kva, VM_PAGE_TO_PHYS(sf->m)); 294done: 295 mtx_unlock(&sf_buf_lock); 296 return (sf); 297} 298 299void 300cpu_set_syscall_retval(struct thread *td, int error) 301{ 302 struct trapframe *frame; 303 int fixup; 304#ifdef __ARMEB__ 305 u_int call; 306#endif 307 308 frame = td->td_frame; 309 fixup = 0; 310 311#ifdef __ARMEB__ 312 /* 313 * __syscall returns an off_t while most other syscalls return an 314 * int. As an off_t is 64-bits and an int is 32-bits we need to 315 * place the returned data into r1. As the lseek and frerebsd6_lseek 316 * syscalls also return an off_t they do not need this fixup. 317 */ 318#ifdef __ARM_EABI__ 319 call = frame->tf_r7; 320#else 321 call = *(u_int32_t *)(frame->tf_pc - INSN_SIZE) & 0x000fffff; 322#endif 323 if (call == SYS___syscall) { 324 register_t *ap = &frame->tf_r0; 325 register_t code = ap[_QUAD_LOWWORD]; 326 if (td->td_proc->p_sysent->sv_mask) 327 code &= td->td_proc->p_sysent->sv_mask; 328 fixup = (code != SYS_freebsd6_lseek && code != SYS_lseek) 329 ? 1 : 0; 330 } 331#endif 332 333 switch (error) { 334 case 0: 335 if (fixup) { 336 frame->tf_r0 = 0; 337 frame->tf_r1 = td->td_retval[0]; 338 } else { 339 frame->tf_r0 = td->td_retval[0]; 340 frame->tf_r1 = td->td_retval[1]; 341 } 342 frame->tf_spsr &= ~PSR_C; /* carry bit */ 343 break; 344 case ERESTART: 345 /* 346 * Reconstruct the pc to point at the swi. 347 */ 348 frame->tf_pc -= INSN_SIZE; 349 break; 350 case EJUSTRETURN: 351 /* nothing to do */ 352 break; 353 default: 354 frame->tf_r0 = error; 355 frame->tf_spsr |= PSR_C; /* carry bit */ 356 break; 357 } 358} 359 360/* 361 * Initialize machine state (pcb and trap frame) for a new thread about to 362 * upcall. Put enough state in the new thread's PCB to get it to go back 363 * userret(), where we can intercept it again to set the return (upcall) 364 * Address and stack, along with those from upcals that are from other sources 365 * such as those generated in thread_userret() itself. 366 */ 367void 368cpu_set_upcall(struct thread *td, struct thread *td0) 369{ 370 371 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe)); 372 bcopy(td0->td_pcb, td->td_pcb, sizeof(struct pcb)); 373 374 td->td_pcb->pcb_regs.sf_r4 = (register_t)fork_return; 375 td->td_pcb->pcb_regs.sf_r5 = (register_t)td; 376 td->td_pcb->pcb_regs.sf_lr = (register_t)fork_trampoline; 377 td->td_pcb->pcb_regs.sf_sp = STACKALIGN(td->td_frame); 378 379 td->td_frame->tf_spsr &= ~PSR_C; 380 td->td_frame->tf_r0 = 0; 381 382 /* Setup to release spin count in fork_exit(). */ 383 td->td_md.md_spinlock_count = 1; 384 td->td_md.md_saved_cspr = PSR_SVC32_MODE; 385} 386 387/* 388 * Set that machine state for performing an upcall that has to 389 * be done in thread_userret() so that those upcalls generated 390 * in thread_userret() itself can be done as well. 391 */ 392void 393cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg, 394 stack_t *stack) 395{ 396 struct trapframe *tf = td->td_frame; 397 398 tf->tf_usr_sp = STACKALIGN((int)stack->ss_sp + stack->ss_size); 399 tf->tf_pc = (int)entry; 400 tf->tf_r0 = (int)arg; 401 tf->tf_spsr = PSR_USR32_MODE; 402} 403 404int 405cpu_set_user_tls(struct thread *td, void *tls_base) 406{ 407 408 td->td_md.md_tp = (register_t)tls_base; 409 if (td == curthread) { 410 critical_enter(); 411#ifdef ARM_TP_ADDRESS 412 *(register_t *)ARM_TP_ADDRESS = (register_t)tls_base; 413#else 414 set_tls((void *)tls_base); 415#endif 416 critical_exit(); 417 } 418 return (0); 419} 420 421void 422cpu_thread_exit(struct thread *td) 423{ 424} 425 426void 427cpu_thread_alloc(struct thread *td) 428{ 429 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_pages * 430 PAGE_SIZE) - 1; 431 /* 432 * Ensure td_frame is aligned to an 8 byte boundary as it will be 433 * placed into the stack pointer which must be 8 byte aligned in 434 * the ARM EABI. 435 */ 436 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb) - 1; 437 438#ifdef __XSCALE__ 439#ifndef CPU_XSCALE_CORE3 440 pmap_use_minicache(td->td_kstack, td->td_kstack_pages * PAGE_SIZE); 441#endif 442#endif 443} 444 445void 446cpu_thread_free(struct thread *td) 447{ 448} 449 450void 451cpu_thread_clean(struct thread *td) 452{ 453} 454 455/* 456 * Intercept the return address from a freshly forked process that has NOT 457 * been scheduled yet. 458 * 459 * This is needed to make kernel threads stay in kernel mode. 460 */ 461void 462cpu_set_fork_handler(struct thread *td, void (*func)(void *), void *arg) 463{ 464 td->td_pcb->pcb_regs.sf_r4 = (register_t)func; /* function */ 465 td->td_pcb->pcb_regs.sf_r5 = (register_t)arg; /* first arg */ 466} 467 468/* 469 * Software interrupt handler for queued VM system processing. 470 */ 471void 472swi_vm(void *dummy) 473{ 474 475 if (busdma_swi_pending) 476 busdma_swi(); 477} 478 479void 480cpu_exit(struct thread *td) 481{ 482} 483 484