1 /* $NetBSD: vm_machdep.c,v 1.75 2018/07/12 12:48:50 jakllsch 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 1.75 2018/07/12 12:48:50 jakllsch Exp $"); 48 49 #include "opt_armfpe.h" 50 #include "opt_pmap_debug.h" 51 #include "opt_cputypes.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/cpu.h> 59 #include <sys/buf.h> 60 #include <sys/exec.h> 61 #include <sys/syslog.h> 62 63 #include <uvm/uvm_extern.h> 64 65 #include <arm/vfpreg.h> 66 67 #include <machine/pcb.h> 68 #include <machine/pmap.h> 69 #include <machine/reg.h> 70 #include <machine/vmparam.h> 71 72 void lwp_trampoline(void); 73 74 /* 75 * Special compilation symbols: 76 * 77 * STACKCHECKS - Fill undefined and supervisor stacks with a known pattern 78 * on forking and check the pattern on exit, reporting 79 * the amount of stack used. 80 */ 81 82 void 83 cpu_proc_fork(struct proc *p1, struct proc *p2) 84 { 85 /* 86 * Copy machine arch string (it's small so just memcpy it). 87 */ 88 memcpy(p2->p_md.md_march, p1->p_md.md_march, sizeof(p2->p_md.md_march)); 89 } 90 91 /* 92 * Finish a fork operation, with LWP l2 nearly set up. 93 * 94 * Copy and update the pcb and trapframe, making the child ready to run. 95 * 96 * Rig the child's kernel stack so that it will start out in 97 * lwp_trampoline() which will call the specified func with the argument arg. 98 * 99 * If an alternate user-level stack is requested (with non-zero values 100 * in both the stack and stacksize args), set up the user stack pointer 101 * accordingly. 102 */ 103 void 104 cpu_lwp_fork(struct lwp *l1, struct lwp *l2, void *stack, size_t stacksize, 105 void (*func)(void *), void *arg) 106 { 107 struct switchframe *sf; 108 vaddr_t uv; 109 110 const struct pcb * const pcb1 = lwp_getpcb(l1); 111 struct pcb * const pcb2 = lwp_getpcb(l2); 112 113 #ifdef PMAP_DEBUG 114 if (pmap_debug_level > 0) 115 printf("cpu_lwp_fork: %p %p %p %p\n", l1, l2, curlwp, &lwp0); 116 #endif /* PMAP_DEBUG */ 117 118 /* Copy the pcb */ 119 *pcb2 = *pcb1; 120 121 #ifdef FPU_VFP 122 /* 123 * Disable the VFP for a newly created LWP but remember if the 124 * VFP state is valid. 125 */ 126 pcb2->pcb_vfp.vfp_fpexc &= ~VFP_FPEXC_EN; 127 #endif 128 129 /* 130 * Set up the kernel stack for the process. 131 * Note: this stack is not in use if we are forking from p1 132 */ 133 uv = uvm_lwp_getuarea(l2); 134 pcb2->pcb_ksp = uv + USPACE_SVC_STACK_TOP; 135 136 #ifdef STACKCHECKS 137 /* Fill the kernel stack with a known pattern */ 138 memset((void *)(uv + USPACE_SVC_STACK_BOTTOM), 0xdd, 139 (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM)); 140 #endif /* STACKCHECKS */ 141 142 #ifdef PMAP_DEBUG 143 if (pmap_debug_level > 0) { 144 printf("l1: pcb=%p pid=%d pmap=%p\n", 145 pcb1, l1->l_lid, l1->l_proc->p_vmspace->vm_map.pmap); 146 printf("l2: pcb=%p pid=%d pmap=%p\n", 147 pcb2, l2->l_lid, l2->l_proc->p_vmspace->vm_map.pmap); 148 } 149 #endif /* PMAP_DEBUG */ 150 151 struct trapframe *tf = (struct trapframe *)pcb2->pcb_ksp - 1; 152 lwp_settrapframe(l2, tf); 153 *tf = *lwp_trapframe(l1); 154 155 /* 156 * If specified, give the child a different stack (make sure 157 * it's 8-byte aligned). 158 */ 159 if (stack != NULL) 160 tf->tf_usr_sp = ((vaddr_t)(stack) + stacksize) & -8; 161 162 sf = (struct switchframe *)tf - 1; 163 sf->sf_r4 = (u_int)func; 164 sf->sf_r5 = (u_int)arg; 165 sf->sf_r7 = PSR_USR32_MODE; /* for returning to userspace */ 166 sf->sf_sp = (u_int)tf; 167 sf->sf_pc = (u_int)lwp_trampoline; 168 pcb2->pcb_ksp = (u_int)sf; 169 } 170 171 /* 172 * cpu_exit is called as the last action during exit. 173 * 174 * We clean up a little and then call switch_exit() with the old proc as an 175 * argument. switch_exit() first switches to lwp0's context, and finally 176 * jumps into switch() to wait for another process to wake up. 177 */ 178 179 void 180 cpu_lwp_free(struct lwp *l, int proc) 181 { 182 #ifdef STACKCHECKS 183 /* Report how much stack has been used - debugging */ 184 struct pcb * const pcb = lwp_getpcb(l); 185 u_char *ptr; 186 u_int loop; 187 188 ptr = (u_char *)pcb + USPACE_SVC_STACK_BOTTOM; 189 for (loop = 0; loop < (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM) 190 && *ptr == 0xdd; ++loop, ++ptr) ; 191 log(LOG_INFO, "%u bytes of svc stack fill pattern\n", loop); 192 #endif /* STACKCHECKS */ 193 } 194 195 void 196 cpu_lwp_free2(struct lwp *l) 197 { 198 } 199 200 /* 201 * Map a user I/O request into kernel virtual address space. 202 * Note: the pages are already locked by uvm_vslock(), so we 203 * do not need to pass an access_type to pmap_enter(). 204 */ 205 int 206 vmapbuf(struct buf *bp, vsize_t len) 207 { 208 struct pmap * const pm = vm_map_pmap(&bp->b_proc->p_vmspace->vm_map); 209 vaddr_t faddr, taddr, off; 210 paddr_t fpa; 211 212 KASSERT(pm != pmap_kernel()); 213 214 #ifdef PMAP_DEBUG 215 if (pmap_debug_level > 0) 216 printf("vmapbuf: bp=%08x buf=%08x len=%08x\n", (u_int)bp, 217 (u_int)bp->b_data, (u_int)len); 218 #endif /* PMAP_DEBUG */ 219 220 if ((bp->b_flags & B_PHYS) == 0) 221 panic("vmapbuf"); 222 223 bp->b_saveaddr = bp->b_data; 224 faddr = trunc_page((vaddr_t)bp->b_data); 225 off = (vaddr_t)bp->b_data - faddr; 226 len = round_page(off + len); 227 taddr = uvm_km_alloc(phys_map, len, atop(faddr) & uvmexp.colormask, 228 UVM_KMF_VAONLY | UVM_KMF_WAITVA | UVM_KMF_COLORMATCH); 229 bp->b_data = (void *)(taddr + off); 230 231 /* 232 * The region is locked, so we expect that pmap_pte() will return 233 * non-NULL. 234 */ 235 while (len) { 236 (void) pmap_extract(pm, faddr, &fpa); 237 pmap_enter(pmap_kernel(), taddr, fpa, VM_PROT_READ|VM_PROT_WRITE, 238 VM_PROT_READ|VM_PROT_WRITE|PMAP_WIRED); 239 faddr += PAGE_SIZE; 240 taddr += PAGE_SIZE; 241 len -= PAGE_SIZE; 242 } 243 pmap_update(pmap_kernel()); 244 245 return 0; 246 } 247 248 /* 249 * Unmap a previously-mapped user I/O request. 250 */ 251 void 252 vunmapbuf(struct buf *bp, vsize_t len) 253 { 254 vaddr_t addr, off; 255 256 #ifdef PMAP_DEBUG 257 if (pmap_debug_level > 0) 258 printf("vunmapbuf: bp=%08x buf=%08x len=%08x\n", 259 (u_int)bp, (u_int)bp->b_data, (u_int)len); 260 #endif /* PMAP_DEBUG */ 261 262 if ((bp->b_flags & B_PHYS) == 0) 263 panic("vunmapbuf"); 264 265 /* 266 * Make sure the cache does not have dirty data for the 267 * pages we had mapped. 268 */ 269 addr = trunc_page((vaddr_t)bp->b_data); 270 off = (vaddr_t)bp->b_data - addr; 271 len = round_page(off + len); 272 273 pmap_remove(pmap_kernel(), addr, addr + len); 274 pmap_update(pmap_kernel()); 275 uvm_km_free(phys_map, addr, len, UVM_KMF_VAONLY); 276 bp->b_data = bp->b_saveaddr; 277 bp->b_saveaddr = 0; 278 } 279 280 void 281 ktext_write(void *to, const void *from, size_t size) 282 { 283 struct pmap *pmap = pmap_kernel(); 284 pd_entry_t *pde, oldpde, tmppde; 285 pt_entry_t *pte, oldpte, tmppte; 286 vaddr_t pgva; 287 size_t limit, savesize; 288 const char *src; 289 char *dst; 290 291 /* XXX: gcc */ 292 oldpte = 0; 293 294 if ((savesize = size) == 0) 295 return; 296 297 dst = (char *) to; 298 src = (const char *) from; 299 300 do { 301 /* Get the PDE of the current VA. */ 302 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == false) 303 goto no_mapping; 304 switch ((oldpde = *pde) & L1_TYPE_MASK) { 305 case L1_TYPE_S: 306 pgva = (vaddr_t)dst & L1_S_FRAME; 307 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET); 308 309 tmppde = l1pte_set_writable(oldpde); 310 *pde = tmppde; 311 PTE_SYNC(pde); 312 break; 313 314 case L1_TYPE_C: 315 pgva = (vaddr_t)dst & L2_S_FRAME; 316 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET); 317 318 if (pte == NULL) 319 goto no_mapping; 320 oldpte = *pte; 321 tmppte = l2pte_set_writable(oldpte); 322 *pte = tmppte; 323 PTE_SYNC(pte); 324 break; 325 326 default: 327 no_mapping: 328 printf(" address 0x%08lx not a valid page\n", 329 (vaddr_t) dst); 330 return; 331 } 332 cpu_tlb_flushD_SE(pgva); 333 cpu_cpwait(); 334 335 if (limit > size) 336 limit = size; 337 size -= limit; 338 339 /* 340 * Page is now writable. Do as much access as we 341 * can in this page. 342 */ 343 for (; limit > 0; limit--) 344 *dst++ = *src++; 345 346 /* 347 * Restore old mapping permissions. 348 */ 349 switch (oldpde & L1_TYPE_MASK) { 350 case L1_TYPE_S: 351 *pde = oldpde; 352 PTE_SYNC(pde); 353 break; 354 355 case L1_TYPE_C: 356 *pte = oldpte; 357 PTE_SYNC(pte); 358 break; 359 } 360 cpu_tlb_flushD_SE(pgva); 361 cpu_cpwait(); 362 } while (size != 0); 363 364 /* Sync the I-cache. */ 365 cpu_icache_sync_range((vaddr_t)to, savesize); 366 } 367 368 /* End of vm_machdep.c */ 369