1 /* $NetBSD: vm_machdep.c,v 1.34 2005/12/11 12:16:41 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1994-1998 Mark Brinicombe. 5 * Copyright (c) 1994 Brini. 6 * All rights reserved. 7 * 8 * This code is derived from software written for Brini by Mark Brinicombe 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 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 the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by Brini. 21 * 4. The name of the company nor the name of the author may be used to 22 * endorse or promote products derived from this software without specific 23 * prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED 26 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 27 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 29 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 30 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * RiscBSD kernel project 38 * 39 * vm_machdep.h 40 * 41 * vm machine specific bits 42 * 43 * Created : 08/10/94 44 */ 45 46 #include <sys/cdefs.h> 47 __KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.34 2005/12/11 12:16:41 christos Exp $"); 48 49 #include "opt_armfpe.h" 50 #include "opt_pmap_debug.h" 51 #include "opt_perfctrs.h" 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/proc.h> 56 #include <sys/malloc.h> 57 #include <sys/vnode.h> 58 #include <sys/buf.h> 59 #include <sys/pmc.h> 60 #include <sys/user.h> 61 #include <sys/exec.h> 62 #include <sys/syslog.h> 63 64 #include <uvm/uvm_extern.h> 65 66 #include <machine/cpu.h> 67 #include <machine/pmap.h> 68 #include <machine/reg.h> 69 #include <machine/vmparam.h> 70 71 #ifdef ARMFPE 72 #include <arm/fpe-arm/armfpe.h> 73 #endif 74 75 extern pv_addr_t systempage; 76 77 int process_read_regs __P((struct proc *p, struct reg *regs)); 78 int process_read_fpregs __P((struct proc *p, struct fpreg *regs)); 79 80 void switch_exit __P((struct lwp *l, struct lwp *l0, 81 void (*)(struct lwp *))); 82 extern void proc_trampoline __P((void)); 83 84 /* 85 * Special compilation symbols: 86 * 87 * STACKCHECKS - Fill undefined and supervisor stacks with a known pattern 88 * on forking and check the pattern on exit, reporting 89 * the amount of stack used. 90 */ 91 92 void 93 cpu_proc_fork(p1, p2) 94 struct proc *p1, *p2; 95 { 96 97 #if defined(PERFCTRS) 98 if (PMC_ENABLED(p1)) 99 pmc_md_fork(p1, p2); 100 else { 101 p2->p_md.pmc_enabled = 0; 102 p2->p_md.pmc_state = NULL; 103 } 104 #endif 105 } 106 107 /* 108 * Finish a fork operation, with process p2 nearly set up. 109 * Copy and update the pcb and trap frame, making the child ready to run. 110 * 111 * Rig the child's kernel stack so that it will start out in 112 * proc_trampoline() and call child_return() with p2 as an 113 * argument. This causes the newly-created child process to go 114 * directly to user level with an apparent return value of 0 from 115 * fork(), while the parent process returns normally. 116 * 117 * p1 is the process being forked; if p1 == &proc0, we are creating 118 * a kernel thread, and the return path and argument are specified with 119 * `func' and `arg'. 120 * 121 * If an alternate user-level stack is requested (with non-zero values 122 * in both the stack and stacksize args), set up the user stack pointer 123 * accordingly. 124 */ 125 void 126 cpu_lwp_fork(l1, l2, stack, stacksize, func, arg) 127 struct lwp *l1; 128 struct lwp *l2; 129 void *stack; 130 size_t stacksize; 131 void (*func) __P((void *)); 132 void *arg; 133 { 134 struct pcb *pcb = (struct pcb *)&l2->l_addr->u_pcb; 135 struct trapframe *tf; 136 struct switchframe *sf; 137 138 #ifdef PMAP_DEBUG 139 if (pmap_debug_level >= 0) 140 printf("cpu_lwp_fork: %p %p %p %p\n", l1, l2, curlwp, &lwp0); 141 #endif /* PMAP_DEBUG */ 142 143 #if 0 /* XXX */ 144 if (l1 == curlwp) { 145 /* Sync the PCB before we copy it. */ 146 savectx(curpcb); 147 } 148 #endif 149 150 /* Copy the pcb */ 151 *pcb = l1->l_addr->u_pcb; 152 153 /* 154 * Set up the undefined stack for the process. 155 * Note: this stack is not in use if we are forking from p1 156 */ 157 pcb->pcb_un.un_32.pcb32_und_sp = (u_int)l2->l_addr + 158 USPACE_UNDEF_STACK_TOP; 159 pcb->pcb_un.un_32.pcb32_sp = (u_int)l2->l_addr + USPACE_SVC_STACK_TOP; 160 161 #ifdef STACKCHECKS 162 /* Fill the undefined stack with a known pattern */ 163 memset(((u_char *)l2->l_addr) + USPACE_UNDEF_STACK_BOTTOM, 0xdd, 164 (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM)); 165 /* Fill the kernel stack with a known pattern */ 166 memset(((u_char *)l2->l_addr) + USPACE_SVC_STACK_BOTTOM, 0xdd, 167 (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM)); 168 #endif /* STACKCHECKS */ 169 170 #ifdef PMAP_DEBUG 171 if (pmap_debug_level >= 0) { 172 printf("l1->procaddr=%p l1->procaddr->u_pcb=%p pid=%d pmap=%p\n", 173 l1->l_addr, &l1->l_addr->u_pcb, l1->l_lid, 174 l1->l_proc->p_vmspace->vm_map.pmap); 175 printf("l2->procaddr=%p l2->procaddr->u_pcb=%p pid=%d pmap=%p\n", 176 l2->l_addr, &l2->l_addr->u_pcb, l2->l_lid, 177 l2->l_proc->p_vmspace->vm_map.pmap); 178 } 179 #endif /* PMAP_DEBUG */ 180 181 pmap_activate(l2); 182 183 #ifdef ARMFPE 184 /* Initialise a new FP context for p2 and copy the context from p1 */ 185 arm_fpe_core_initcontext(FP_CONTEXT(l2)); 186 arm_fpe_copycontext(FP_CONTEXT(l1), FP_CONTEXT(l2)); 187 #endif /* ARMFPE */ 188 189 l2->l_addr->u_pcb.pcb_tf = tf = 190 (struct trapframe *)pcb->pcb_un.un_32.pcb32_sp - 1; 191 *tf = *l1->l_addr->u_pcb.pcb_tf; 192 193 /* 194 * If specified, give the child a different stack. 195 */ 196 if (stack != NULL) 197 tf->tf_usr_sp = (u_int)stack + stacksize; 198 199 sf = (struct switchframe *)tf - 1; 200 sf->sf_r4 = (u_int)func; 201 sf->sf_r5 = (u_int)arg; 202 sf->sf_pc = (u_int)proc_trampoline; 203 pcb->pcb_un.un_32.pcb32_sp = (u_int)sf; 204 } 205 206 void 207 cpu_setfunc(struct lwp *l, void (*func)(void *), void *arg) 208 { 209 struct pcb *pcb = &l->l_addr->u_pcb; 210 struct trapframe *tf = pcb->pcb_tf; 211 struct switchframe *sf = (struct switchframe *)tf - 1; 212 213 sf->sf_r4 = (u_int)func; 214 sf->sf_r5 = (u_int)arg; 215 sf->sf_pc = (u_int)proc_trampoline; 216 pcb->pcb_un.un_32.pcb32_sp = (u_int)sf; 217 } 218 219 /* 220 * cpu_exit is called as the last action during exit. 221 * 222 * We clean up a little and then call switch_exit() with the old proc as an 223 * argument. switch_exit() first switches to proc0's context, and finally 224 * jumps into switch() to wait for another process to wake up. 225 */ 226 227 void 228 cpu_lwp_free(struct lwp *l, int proc) 229 { 230 #ifdef ARMFPE 231 /* Abort any active FP operation and deactivate the context */ 232 arm_fpe_core_abort(FP_CONTEXT(l), NULL, NULL); 233 arm_fpe_core_changecontext(0); 234 #endif /* ARMFPE */ 235 236 #ifdef STACKCHECKS 237 /* Report how much stack has been used - debugging */ 238 if (l) { 239 u_char *ptr; 240 int loop; 241 242 ptr = ((u_char *)p2->p_addr) + USPACE_UNDEF_STACK_BOTTOM; 243 for (loop = 0; loop < (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM) 244 && *ptr == 0xdd; ++loop, ++ptr) ; 245 log(LOG_INFO, "%d bytes of undefined stack fill pattern\n", loop); 246 ptr = ((u_char *)p2->p_addr) + USPACE_SVC_STACK_BOTTOM; 247 for (loop = 0; loop < (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM) 248 && *ptr == 0xdd; ++loop, ++ptr) ; 249 log(LOG_INFO, "%d bytes of svc stack fill pattern\n", loop); 250 } 251 #endif /* STACKCHECKS */ 252 } 253 254 void 255 cpu_exit(struct lwp *l) 256 { 257 switch_exit(l, &lwp0, lwp_exit2); 258 } 259 260 void 261 cpu_swapin(l) 262 struct lwp *l; 263 { 264 #if 0 265 struct proc *p = l->l_proc; 266 267 /* Don't do this. See the comment in cpu_swapout(). */ 268 #ifdef PMAP_DEBUG 269 if (pmap_debug_level >= 0) 270 printf("cpu_swapin(%p, %d, %s, %p)\n", l, l->l_lid, 271 p->p_comm, p->p_vmspace->vm_map.pmap); 272 #endif /* PMAP_DEBUG */ 273 274 if (vector_page < KERNEL_BASE) { 275 /* Map the vector page */ 276 pmap_enter(p->p_vmspace->vm_map.pmap, vector_page, 277 systempage.pv_pa, VM_PROT_READ, VM_PROT_READ|PMAP_WIRED); 278 pmap_update(p->p_vmspace->vm_map.pmap); 279 } 280 #endif 281 } 282 283 284 void 285 cpu_swapout(l) 286 struct lwp *l; 287 { 288 #if 0 289 struct proc *p = l->l_proc; 290 291 /* 292 * Don't do this! If the pmap is shared with another process, 293 * it will loose it's page0 entry. That's bad news indeed. 294 */ 295 #ifdef PMAP_DEBUG 296 if (pmap_debug_level >= 0) 297 printf("cpu_swapout(%p, %d, %s, %p)\n", l, l->l_lid, 298 p->p_comm, &p->p_vmspace->vm_map.pmap); 299 #endif /* PMAP_DEBUG */ 300 301 if (vector_page < KERNEL_BASE) { 302 /* Free the system page mapping */ 303 pmap_remove(p->p_vmspace->vm_map.pmap, vector_page, 304 vector_page + PAGE_SIZE); 305 pmap_update(p->p_vmspace->vm_map.pmap); 306 } 307 #endif 308 } 309 310 /* 311 * Map a user I/O request into kernel virtual address space. 312 * Note: the pages are already locked by uvm_vslock(), so we 313 * do not need to pass an access_type to pmap_enter(). 314 */ 315 void 316 vmapbuf(bp, len) 317 struct buf *bp; 318 vsize_t len; 319 { 320 vaddr_t faddr, taddr, off; 321 paddr_t fpa; 322 323 324 #ifdef PMAP_DEBUG 325 if (pmap_debug_level >= 0) 326 printf("vmapbuf: bp=%08x buf=%08x len=%08x\n", (u_int)bp, 327 (u_int)bp->b_data, (u_int)len); 328 #endif /* PMAP_DEBUG */ 329 330 if ((bp->b_flags & B_PHYS) == 0) 331 panic("vmapbuf"); 332 333 faddr = trunc_page((vaddr_t)bp->b_saveaddr = bp->b_data); 334 off = (vaddr_t)bp->b_data - faddr; 335 len = round_page(off + len); 336 taddr = uvm_km_alloc(phys_map, len, 0, UVM_KMF_VAONLY | UVM_KMF_WAITVA); 337 bp->b_data = (caddr_t)(taddr + off); 338 339 /* 340 * The region is locked, so we expect that pmap_pte() will return 341 * non-NULL. 342 */ 343 while (len) { 344 (void) pmap_extract(vm_map_pmap(&bp->b_proc->p_vmspace->vm_map), 345 faddr, &fpa); 346 pmap_enter(pmap_kernel(), taddr, fpa, 347 VM_PROT_READ|VM_PROT_WRITE, VM_PROT_READ|VM_PROT_WRITE|PMAP_WIRED); 348 faddr += PAGE_SIZE; 349 taddr += PAGE_SIZE; 350 len -= PAGE_SIZE; 351 } 352 pmap_update(pmap_kernel()); 353 } 354 355 /* 356 * Unmap a previously-mapped user I/O request. 357 */ 358 void 359 vunmapbuf(bp, len) 360 struct buf *bp; 361 vsize_t len; 362 { 363 vaddr_t addr, off; 364 365 #ifdef PMAP_DEBUG 366 if (pmap_debug_level >= 0) 367 printf("vunmapbuf: bp=%08x buf=%08x len=%08x\n", 368 (u_int)bp, (u_int)bp->b_data, (u_int)len); 369 #endif /* PMAP_DEBUG */ 370 371 if ((bp->b_flags & B_PHYS) == 0) 372 panic("vunmapbuf"); 373 374 /* 375 * Make sure the cache does not have dirty data for the 376 * pages we had mapped. 377 */ 378 addr = trunc_page((vaddr_t)bp->b_data); 379 off = (vaddr_t)bp->b_data - addr; 380 len = round_page(off + len); 381 382 pmap_remove(pmap_kernel(), addr, addr + len); 383 pmap_update(pmap_kernel()); 384 uvm_km_free(phys_map, addr, len, UVM_KMF_VAONLY); 385 bp->b_data = bp->b_saveaddr; 386 bp->b_saveaddr = 0; 387 } 388 389 /* End of vm_machdep.c */ 390