1 /* $NetBSD: vm_machdep.c,v 1.13 2002/01/29 23:02:48 thorpej 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 "opt_armfpe.h" 47 #include "opt_pmap_debug.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/proc.h> 52 #include <sys/malloc.h> 53 #include <sys/vnode.h> 54 #include <sys/buf.h> 55 #include <sys/user.h> 56 #include <sys/exec.h> 57 #include <sys/syslog.h> 58 59 #include <uvm/uvm_extern.h> 60 61 #include <machine/cpu.h> 62 #include <machine/pmap.h> 63 #include <machine/reg.h> 64 #include <machine/vmparam.h> 65 66 #ifdef ARMFPE 67 #include <arm/fpe-arm/armfpe.h> 68 #endif 69 70 extern pv_addr_t systempage; 71 72 int process_read_regs __P((struct proc *p, struct reg *regs)); 73 int process_read_fpregs __P((struct proc *p, struct fpreg *regs)); 74 75 void switch_exit __P((struct proc *p)); 76 extern void proc_trampoline __P((void)); 77 78 /* 79 * Special compilation symbols: 80 * 81 * STACKCHECKS - Fill undefined and supervisor stacks with a known pattern 82 * on forking and check the pattern on exit, reporting 83 * the amount of stack used. 84 */ 85 86 /* 87 * Finish a fork operation, with process p2 nearly set up. 88 * Copy and update the pcb and trap frame, making the child ready to run. 89 * 90 * Rig the child's kernel stack so that it will start out in 91 * proc_trampoline() and call child_return() with p2 as an 92 * argument. This causes the newly-created child process to go 93 * directly to user level with an apparent return value of 0 from 94 * fork(), while the parent process returns normally. 95 * 96 * p1 is the process being forked; if p1 == &proc0, we are creating 97 * a kernel thread, and the return path and argument are specified with 98 * `func' and `arg'. 99 * 100 * If an alternate user-level stack is requested (with non-zero values 101 * in both the stack and stacksize args), set up the user stack pointer 102 * accordingly. 103 */ 104 void 105 cpu_fork(p1, p2, stack, stacksize, func, arg) 106 struct proc *p1; 107 struct proc *p2; 108 void *stack; 109 size_t stacksize; 110 void (*func) __P((void *)); 111 void *arg; 112 { 113 struct pcb *pcb = (struct pcb *)&p2->p_addr->u_pcb; 114 struct trapframe *tf; 115 struct switchframe *sf; 116 117 #ifdef PMAP_DEBUG 118 if (pmap_debug_level >= 0) 119 printf("cpu_fork: %p %p %p %p\n", p1, p2, curproc, &proc0); 120 #endif /* PMAP_DEBUG */ 121 122 #if 0 /* XXX */ 123 if (p1 == curproc) { 124 /* Sync the PCB before we copy it. */ 125 savectx(curpcb); 126 } 127 #endif 128 129 /* Copy the pcb */ 130 *pcb = p1->p_addr->u_pcb; 131 132 /* 133 * Set up the undefined stack for the process. 134 * Note: this stack is not in use if we are forking from p1 135 */ 136 pcb->pcb_un.un_32.pcb32_und_sp = (u_int)p2->p_addr + 137 USPACE_UNDEF_STACK_TOP; 138 pcb->pcb_un.un_32.pcb32_sp = (u_int)p2->p_addr + USPACE_SVC_STACK_TOP; 139 140 #ifdef STACKCHECKS 141 /* Fill the undefined stack with a known pattern */ 142 memset(((u_char *)p2->p_addr) + USPACE_UNDEF_STACK_BOTTOM, 0xdd, 143 (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM)); 144 /* Fill the kernel stack with a known pattern */ 145 memset(((u_char *)p2->p_addr) + USPACE_SVC_STACK_BOTTOM, 0xdd, 146 (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM)); 147 #endif /* STACKCHECKS */ 148 149 #ifdef PMAP_DEBUG 150 if (pmap_debug_level >= 0) { 151 printf("p1->procaddr=%p p1->procaddr->u_pcb=%p pid=%d pmap=%p\n", 152 p1->p_addr, &p1->p_addr->u_pcb, p1->p_pid, 153 p1->p_vmspace->vm_map.pmap); 154 printf("p2->procaddr=%p p2->procaddr->u_pcb=%p pid=%d pmap=%p\n", 155 p2->p_addr, &p2->p_addr->u_pcb, p2->p_pid, 156 p2->p_vmspace->vm_map.pmap); 157 } 158 #endif /* PMAP_DEBUG */ 159 160 pmap_activate(p2); 161 162 #ifdef ARMFPE 163 /* Initialise a new FP context for p2 and copy the context from p1 */ 164 arm_fpe_core_initcontext(FP_CONTEXT(p2)); 165 arm_fpe_copycontext(FP_CONTEXT(p1), FP_CONTEXT(p2)); 166 #endif /* ARMFPE */ 167 168 p2->p_addr->u_pcb.pcb_tf = tf = 169 (struct trapframe *)pcb->pcb_un.un_32.pcb32_sp - 1; 170 *tf = *p1->p_addr->u_pcb.pcb_tf; 171 172 /* 173 * If specified, give the child a different stack. 174 */ 175 if (stack != NULL) 176 tf->tf_usr_sp = (u_int)stack + stacksize; 177 178 sf = (struct switchframe *)tf - 1; 179 sf->sf_spl = 0; /* always equivalent to spl0() */ 180 sf->sf_r4 = (u_int)func; 181 sf->sf_r5 = (u_int)arg; 182 sf->sf_pc = (u_int)proc_trampoline; 183 pcb->pcb_un.un_32.pcb32_sp = (u_int)sf; 184 } 185 186 /* 187 * cpu_exit is called as the last action during exit. 188 * 189 * We clean up a little and then call switch_exit() with the old proc as an 190 * argument. switch_exit() first switches to proc0's context, and finally 191 * jumps into switch() to wait for another process to wake up. 192 */ 193 194 void 195 cpu_exit(p) 196 register struct proc *p; 197 { 198 #ifdef ARMFPE 199 /* Abort any active FP operation and deactivate the context */ 200 arm_fpe_core_abort(FP_CONTEXT(p), NULL, NULL); 201 arm_fpe_core_changecontext(0); 202 #endif /* ARMFPE */ 203 204 #ifdef STACKCHECKS 205 /* Report how much stack has been used - debugging */ 206 if (p) { 207 u_char *ptr; 208 int loop; 209 210 ptr = ((u_char *)p2->p_addr) + USPACE_UNDEF_STACK_BOTTOM; 211 for (loop = 0; loop < (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM) 212 && *ptr == 0xdd; ++loop, ++ptr) ; 213 log(LOG_INFO, "%d bytes of undefined stack fill pattern\n", loop); 214 ptr = ((u_char *)p2->p_addr) + USPACE_SVC_STACK_BOTTOM; 215 for (loop = 0; loop < (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM) 216 && *ptr == 0xdd; ++loop, ++ptr) ; 217 log(LOG_INFO, "%d bytes of svc stack fill pattern\n", loop); 218 } 219 #endif /* STACKCHECKS */ 220 uvmexp.swtch++; 221 switch_exit(p); 222 } 223 224 225 void 226 cpu_swapin(p) 227 struct proc *p; 228 { 229 #if 0 230 /* Don't do this. See the comment in cpu_swapout(). */ 231 #ifdef PMAP_DEBUG 232 if (pmap_debug_level >= 0) 233 printf("cpu_swapin(%p, %d, %s, %p)\n", p, p->p_pid, 234 p->p_comm, p->p_vmspace->vm_map.pmap); 235 #endif /* PMAP_DEBUG */ 236 237 /* Map the system page */ 238 pmap_enter(p->p_vmspace->vm_map.pmap, 0x00000000, systempage.pv_pa, 239 VM_PROT_READ, VM_PROT_READ|PMAP_WIRED); 240 pmap_update(p->p_vmspace->vm_map.pmap); 241 #endif 242 } 243 244 245 void 246 cpu_swapout(p) 247 struct proc *p; 248 { 249 #if 0 250 /* 251 * Don't do this! If the pmap is shared with another process, 252 * it will loose it's page0 entry. That's bad news indeed. 253 */ 254 #ifdef PMAP_DEBUG 255 if (pmap_debug_level >= 0) 256 printf("cpu_swapout(%p, %d, %s, %p)\n", p, p->p_pid, 257 p->p_comm, &p->p_vmspace->vm_map.pmap); 258 #endif /* PMAP_DEBUG */ 259 260 /* Free the system page mapping */ 261 pmap_remove(p->p_vmspace->vm_map.pmap, 0x00000000, 0x00000000 + NBPG); 262 pmap_update(p->p_vmspace->vm_map.pmap); 263 #endif 264 } 265 266 267 /* 268 * Move pages from one kernel virtual address to another. 269 * Both addresses are assumed to reside in the Sysmap, 270 * and size must be a multiple of CLSIZE. 271 */ 272 273 void 274 pagemove(from, to, size) 275 caddr_t from, to; 276 size_t size; 277 { 278 register pt_entry_t *fpte, *tpte; 279 280 if (size % NBPG) 281 panic("pagemove: size=%08lx", (u_long) size); 282 283 #ifdef PMAP_DEBUG 284 if (pmap_debug_level >= 0) 285 printf("pagemove: V%p to %p size %08lx\n", 286 from, to, (u_long) size); 287 #endif /* PMAP_DEBUG */ 288 289 fpte = vtopte((vaddr_t)from); 290 tpte = vtopte((vaddr_t)to); 291 292 /* 293 * Make sure the cache does not have dirty data for the 294 * pages we are moving. Pages in the buffers are only 295 * ever moved with pagemove, so we only need to clean 296 * the 'from' area. 297 */ 298 299 cpu_dcache_wbinv_range((vaddr_t) from, size); 300 301 while (size > 0) { 302 *tpte++ = *fpte; 303 *fpte++ = 0; 304 size -= NBPG; 305 } 306 //cpu_tlb_flushD(); 307 } 308 309 extern struct vm_map *phys_map; 310 311 /* 312 * Map a user I/O request into kernel virtual address space. 313 * Note: the pages are already locked by uvm_vslock(), so we 314 * do not need to pass an access_type to pmap_enter(). 315 */ 316 void 317 vmapbuf(bp, len) 318 struct buf *bp; 319 vsize_t len; 320 { 321 vaddr_t faddr, taddr, off; 322 paddr_t fpa; 323 324 325 #ifdef PMAP_DEBUG 326 if (pmap_debug_level >= 0) 327 printf("vmapbuf: bp=%08x buf=%08x len=%08x\n", (u_int)bp, 328 (u_int)bp->b_data, (u_int)len); 329 #endif /* PMAP_DEBUG */ 330 331 if ((bp->b_flags & B_PHYS) == 0) 332 panic("vmapbuf"); 333 334 faddr = trunc_page((vaddr_t)bp->b_saveaddr = bp->b_data); 335 off = (vaddr_t)bp->b_data - faddr; 336 len = round_page(off + len); 337 taddr = uvm_km_valloc_wait(phys_map, len); 338 bp->b_data = (caddr_t)(taddr + off); 339 340 /* 341 * The region is locked, so we expect that pmap_pte() will return 342 * non-NULL. 343 */ 344 while (len) { 345 (void) pmap_extract(vm_map_pmap(&bp->b_proc->p_vmspace->vm_map), 346 faddr, &fpa); 347 pmap_enter(pmap_kernel(), taddr, fpa, 348 VM_PROT_READ|VM_PROT_WRITE, PMAP_WIRED); 349 faddr += PAGE_SIZE; 350 taddr += PAGE_SIZE; 351 len -= PAGE_SIZE; 352 } 353 pmap_update(pmap_kernel()); 354 } 355 356 /* 357 * Unmap a previously-mapped user I/O request. 358 */ 359 void 360 vunmapbuf(bp, len) 361 struct buf *bp; 362 vsize_t len; 363 { 364 vaddr_t addr, off; 365 366 #ifdef PMAP_DEBUG 367 if (pmap_debug_level >= 0) 368 printf("vunmapbuf: bp=%08x buf=%08x len=%08x\n", 369 (u_int)bp, (u_int)bp->b_data, (u_int)len); 370 #endif /* PMAP_DEBUG */ 371 372 if ((bp->b_flags & B_PHYS) == 0) 373 panic("vunmapbuf"); 374 375 /* 376 * Make sure the cache does not have dirty data for the 377 * pages we had mapped. 378 */ 379 addr = trunc_page((vaddr_t)bp->b_data); 380 off = (vaddr_t)bp->b_data - addr; 381 len = round_page(off + len); 382 383 pmap_remove(pmap_kernel(), addr, addr + len); 384 pmap_update(pmap_kernel()); 385 uvm_km_free_wakeup(phys_map, addr, len); 386 bp->b_data = bp->b_saveaddr; 387 bp->b_saveaddr = 0; 388 } 389 390 /* End of vm_machdep.c */ 391