xref: /netbsd-src/sys/arch/arm/arm32/vm_machdep.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: vm_machdep.c,v 1.28 2003/05/17 00:41:36 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 #include "opt_perfctrs.h"
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/malloc.h>
54 #include <sys/vnode.h>
55 #include <sys/buf.h>
56 #include <sys/pmc.h>
57 #include <sys/user.h>
58 #include <sys/exec.h>
59 #include <sys/syslog.h>
60 
61 #include <uvm/uvm_extern.h>
62 
63 #include <machine/cpu.h>
64 #include <machine/pmap.h>
65 #include <machine/reg.h>
66 #include <machine/vmparam.h>
67 
68 #ifdef ARMFPE
69 #include <arm/fpe-arm/armfpe.h>
70 #endif
71 
72 extern pv_addr_t systempage;
73 
74 int process_read_regs	__P((struct proc *p, struct reg *regs));
75 int process_read_fpregs	__P((struct proc *p, struct fpreg *regs));
76 
77 void	switch_exit	__P((struct lwp *l, struct lwp *l0,
78 			     void (*)(struct lwp *)));
79 extern void proc_trampoline	__P((void));
80 
81 /*
82  * Special compilation symbols:
83  *
84  * STACKCHECKS - Fill undefined and supervisor stacks with a known pattern
85  *		 on forking and check the pattern on exit, reporting
86  *		 the amount of stack used.
87  */
88 
89 void
90 cpu_proc_fork(p1, p2)
91 	struct proc *p1, *p2;
92 {
93 
94 #if defined(PERFCTRS)
95 	if (PMC_ENABLED(p1))
96 		pmc_md_fork(p1, p2);
97 	else {
98 		p2->p_md.pmc_enabled = 0;
99 		p2->p_md.pmc_state = NULL;
100 	}
101 #endif
102 }
103 
104 /*
105  * Finish a fork operation, with process p2 nearly set up.
106  * Copy and update the pcb and trap frame, making the child ready to run.
107  *
108  * Rig the child's kernel stack so that it will start out in
109  * proc_trampoline() and call child_return() with p2 as an
110  * argument. This causes the newly-created child process to go
111  * directly to user level with an apparent return value of 0 from
112  * fork(), while the parent process returns normally.
113  *
114  * p1 is the process being forked; if p1 == &proc0, we are creating
115  * a kernel thread, and the return path and argument are specified with
116  * `func' and `arg'.
117  *
118  * If an alternate user-level stack is requested (with non-zero values
119  * in both the stack and stacksize args), set up the user stack pointer
120  * accordingly.
121  */
122 void
123 cpu_lwp_fork(l1, l2, stack, stacksize, func, arg)
124 	struct lwp *l1;
125 	struct lwp *l2;
126 	void *stack;
127 	size_t stacksize;
128 	void (*func) __P((void *));
129 	void *arg;
130 {
131 	struct pcb *pcb = (struct pcb *)&l2->l_addr->u_pcb;
132 	struct trapframe *tf;
133 	struct switchframe *sf;
134 
135 #ifdef PMAP_DEBUG
136 	if (pmap_debug_level >= 0)
137 		printf("cpu_lwp_fork: %p %p %p %p\n", l1, l2, curlwp, &lwp0);
138 #endif	/* PMAP_DEBUG */
139 
140 #if 0 /* XXX */
141 	if (l1 == curlwp) {
142 		/* Sync the PCB before we copy it. */
143 		savectx(curpcb);
144 	}
145 #endif
146 
147 	/* Copy the pcb */
148 	*pcb = l1->l_addr->u_pcb;
149 
150 	/*
151 	 * Set up the undefined stack for the process.
152 	 * Note: this stack is not in use if we are forking from p1
153 	 */
154 	pcb->pcb_un.un_32.pcb32_und_sp = (u_int)l2->l_addr +
155 	    USPACE_UNDEF_STACK_TOP;
156 	pcb->pcb_un.un_32.pcb32_sp = (u_int)l2->l_addr + USPACE_SVC_STACK_TOP;
157 
158 #ifdef STACKCHECKS
159 	/* Fill the undefined stack with a known pattern */
160 	memset(((u_char *)l2->l_addr) + USPACE_UNDEF_STACK_BOTTOM, 0xdd,
161 	    (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM));
162 	/* Fill the kernel stack with a known pattern */
163 	memset(((u_char *)l2->l_addr) + USPACE_SVC_STACK_BOTTOM, 0xdd,
164 	    (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM));
165 #endif	/* STACKCHECKS */
166 
167 #ifdef PMAP_DEBUG
168 	if (pmap_debug_level >= 0) {
169 		printf("l1->procaddr=%p l1->procaddr->u_pcb=%p pid=%d pmap=%p\n",
170 		    l1->l_addr, &l1->l_addr->u_pcb, l1->l_lid,
171 		    l1->l_proc->p_vmspace->vm_map.pmap);
172 		printf("l2->procaddr=%p l2->procaddr->u_pcb=%p pid=%d pmap=%p\n",
173 		    l2->l_addr, &l2->l_addr->u_pcb, l2->l_lid,
174 		    l2->l_proc->p_vmspace->vm_map.pmap);
175 	}
176 #endif	/* PMAP_DEBUG */
177 
178 	pmap_activate(l2);
179 
180 #ifdef ARMFPE
181 	/* Initialise a new FP context for p2 and copy the context from p1 */
182 	arm_fpe_core_initcontext(FP_CONTEXT(l2));
183 	arm_fpe_copycontext(FP_CONTEXT(l1), FP_CONTEXT(l2));
184 #endif	/* ARMFPE */
185 
186 	l2->l_addr->u_pcb.pcb_tf = tf =
187 	    (struct trapframe *)pcb->pcb_un.un_32.pcb32_sp - 1;
188 	*tf = *l1->l_addr->u_pcb.pcb_tf;
189 
190 	/*
191 	 * If specified, give the child a different stack.
192 	 */
193 	if (stack != NULL)
194 		tf->tf_usr_sp = (u_int)stack + stacksize;
195 
196 	sf = (struct switchframe *)tf - 1;
197 	sf->sf_spl = 0;		/* always equivalent to spl0() */
198 	sf->sf_r4 = (u_int)func;
199 	sf->sf_r5 = (u_int)arg;
200 	sf->sf_pc = (u_int)proc_trampoline;
201 	pcb->pcb_un.un_32.pcb32_sp = (u_int)sf;
202 }
203 
204 void
205 cpu_setfunc(struct lwp *l, void (*func)(void *), void *arg)
206 {
207 	struct pcb *pcb = &l->l_addr->u_pcb;
208 	struct trapframe *tf = pcb->pcb_tf;
209 	struct switchframe *sf = (struct switchframe *)tf - 1;
210 
211 	sf->sf_spl = 0;		/* always equivalent to spl0() */
212 	sf->sf_r4 = (u_int)func;
213 	sf->sf_r5 = (u_int)arg;
214 	sf->sf_pc = (u_int)proc_trampoline;
215 	pcb->pcb_un.un_32.pcb32_sp = (u_int)sf;
216 }
217 
218 /*
219  * cpu_exit is called as the last action during exit.
220  *
221  * We clean up a little and then call switch_exit() with the old proc as an
222  * argument.  switch_exit() first switches to proc0's context, and finally
223  * jumps into switch() to wait for another process to wake up.
224  */
225 
226 void
227 cpu_exit(struct lwp *l, int proc)
228 {
229 #ifdef ARMFPE
230 	/* Abort any active FP operation and deactivate the context */
231 	arm_fpe_core_abort(FP_CONTEXT(l), NULL, NULL);
232 	arm_fpe_core_changecontext(0);
233 #endif	/* ARMFPE */
234 
235 #ifdef STACKCHECKS
236 	/* Report how much stack has been used - debugging */
237 	if (l) {
238 		u_char *ptr;
239 		int loop;
240 
241 		ptr = ((u_char *)p2->p_addr) + USPACE_UNDEF_STACK_BOTTOM;
242 		for (loop = 0; loop < (USPACE_UNDEF_STACK_TOP - USPACE_UNDEF_STACK_BOTTOM)
243 		    && *ptr == 0xdd; ++loop, ++ptr) ;
244 		log(LOG_INFO, "%d bytes of undefined stack fill pattern\n", loop);
245 		ptr = ((u_char *)p2->p_addr) + USPACE_SVC_STACK_BOTTOM;
246 		for (loop = 0; loop < (USPACE_SVC_STACK_TOP - USPACE_SVC_STACK_BOTTOM)
247 		    && *ptr == 0xdd; ++loop, ++ptr) ;
248 		log(LOG_INFO, "%d bytes of svc stack fill pattern\n", loop);
249 	}
250 #endif	/* STACKCHECKS */
251 	uvmexp.swtch++;
252 	switch_exit(l, &lwp0, proc ? exit2 : lwp_exit2);
253 }
254 
255 
256 void
257 cpu_swapin(l)
258 	struct lwp *l;
259 {
260 #if 0
261 	struct proc *p = l->l_proc;
262 
263 	/* Don't do this.  See the comment in cpu_swapout().  */
264 #ifdef PMAP_DEBUG
265 	if (pmap_debug_level >= 0)
266 		printf("cpu_swapin(%p, %d, %s, %p)\n", l, l->l_lid,
267 		    p->p_comm, p->p_vmspace->vm_map.pmap);
268 #endif	/* PMAP_DEBUG */
269 
270 	if (vector_page < KERNEL_BASE) {
271 		/* Map the vector page */
272 		pmap_enter(p->p_vmspace->vm_map.pmap, vector_page,
273 		    systempage.pv_pa, VM_PROT_READ, VM_PROT_READ|PMAP_WIRED);
274 		pmap_update(p->p_vmspace->vm_map.pmap);
275 	}
276 #endif
277 }
278 
279 
280 void
281 cpu_swapout(l)
282 	struct lwp *l;
283 {
284 #if 0
285 	struct proc *p = l->l_proc;
286 
287 	/*
288 	 * Don't do this!  If the pmap is shared with another process,
289 	 * it will loose it's page0 entry.  That's bad news indeed.
290 	 */
291 #ifdef PMAP_DEBUG
292 	if (pmap_debug_level >= 0)
293 		printf("cpu_swapout(%p, %d, %s, %p)\n", l, l->l_lid,
294 		    p->p_comm, &p->p_vmspace->vm_map.pmap);
295 #endif	/* PMAP_DEBUG */
296 
297 	if (vector_page < KERNEL_BASE) {
298 		/* Free the system page mapping */
299 		pmap_remove(p->p_vmspace->vm_map.pmap, vector_page,
300 		    vector_page + PAGE_SIZE);
301 		pmap_update(p->p_vmspace->vm_map.pmap);
302 	}
303 #endif
304 }
305 
306 
307 /*
308  * Move pages from one kernel virtual address to another.
309  * Both addresses are assumed to reside in the Sysmap,
310  * and size must be a multiple of PAGE_SIZE.
311  */
312 
313 void
314 pagemove(from, to, size)
315 	caddr_t from, to;
316 	size_t size;
317 {
318 	paddr_t pa;
319 	boolean_t rv;
320 
321 	if (size % PAGE_SIZE)
322 		panic("pagemove: size=%08lx", (u_long) size);
323 
324 	while (size > 0) {
325 		rv = pmap_extract(pmap_kernel(), (vaddr_t) from, &pa);
326 #ifdef DEBUG
327 		if (rv == FALSE)
328 			panic("pagemove 2");
329 		if (pmap_extract(pmap_kernel(), (vaddr_t) to, NULL) == TRUE)
330 			panic("pagemove 3");
331 #endif
332 		pmap_kremove((vaddr_t) from, PAGE_SIZE);
333 		pmap_kenter_pa((vaddr_t) to, pa, VM_PROT_READ|VM_PROT_WRITE);
334 		from += PAGE_SIZE;
335 		to += PAGE_SIZE;
336 		size -= PAGE_SIZE;
337 	}
338 	pmap_update(pmap_kernel());
339 }
340 
341 /*
342  * Map a user I/O request into kernel virtual address space.
343  * Note: the pages are already locked by uvm_vslock(), so we
344  * do not need to pass an access_type to pmap_enter().
345  */
346 void
347 vmapbuf(bp, len)
348 	struct buf *bp;
349 	vsize_t len;
350 {
351 	vaddr_t faddr, taddr, off;
352 	paddr_t fpa;
353 
354 
355 #ifdef PMAP_DEBUG
356 	if (pmap_debug_level >= 0)
357 		printf("vmapbuf: bp=%08x buf=%08x len=%08x\n", (u_int)bp,
358 		    (u_int)bp->b_data, (u_int)len);
359 #endif	/* PMAP_DEBUG */
360 
361 	if ((bp->b_flags & B_PHYS) == 0)
362 		panic("vmapbuf");
363 
364 	faddr = trunc_page((vaddr_t)bp->b_saveaddr = bp->b_data);
365 	off = (vaddr_t)bp->b_data - faddr;
366 	len = round_page(off + len);
367 	taddr = uvm_km_valloc_wait(phys_map, len);
368 	bp->b_data = (caddr_t)(taddr + off);
369 
370 	/*
371 	 * The region is locked, so we expect that pmap_pte() will return
372 	 * non-NULL.
373 	 */
374 	while (len) {
375 		(void) pmap_extract(vm_map_pmap(&bp->b_proc->p_vmspace->vm_map),
376 		    faddr, &fpa);
377 		pmap_enter(pmap_kernel(), taddr, fpa,
378 			VM_PROT_READ|VM_PROT_WRITE, VM_PROT_READ|VM_PROT_WRITE|PMAP_WIRED);
379 		faddr += PAGE_SIZE;
380 		taddr += PAGE_SIZE;
381 		len -= PAGE_SIZE;
382 	}
383 	pmap_update(pmap_kernel());
384 }
385 
386 /*
387  * Unmap a previously-mapped user I/O request.
388  */
389 void
390 vunmapbuf(bp, len)
391 	struct buf *bp;
392 	vsize_t len;
393 {
394 	vaddr_t addr, off;
395 
396 #ifdef PMAP_DEBUG
397 	if (pmap_debug_level >= 0)
398 		printf("vunmapbuf: bp=%08x buf=%08x len=%08x\n",
399 		    (u_int)bp, (u_int)bp->b_data, (u_int)len);
400 #endif	/* PMAP_DEBUG */
401 
402 	if ((bp->b_flags & B_PHYS) == 0)
403 		panic("vunmapbuf");
404 
405 	/*
406 	 * Make sure the cache does not have dirty data for the
407 	 * pages we had mapped.
408 	 */
409 	addr = trunc_page((vaddr_t)bp->b_data);
410 	off = (vaddr_t)bp->b_data - addr;
411 	len = round_page(off + len);
412 
413 	pmap_remove(pmap_kernel(), addr, addr + len);
414 	pmap_update(pmap_kernel());
415 	uvm_km_free_wakeup(phys_map, addr, len);
416 	bp->b_data = bp->b_saveaddr;
417 	bp->b_saveaddr = 0;
418 }
419 
420 /* End of vm_machdep.c */
421