xref: /freebsd/sys/powerpc/booke/pmap_32.c (revision d8f9d3388f5dfed0b426d11a1b985397c12010e8)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (C) 2020 Justin Hibbits
5  * Copyright (C) 2007-2009 Semihalf, Rafal Jaworowski <raj@semihalf.com>
6  * Copyright (C) 2006 Semihalf, Marian Balakowicz <m8@semihalf.com>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
21  * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
24  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
25  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
26  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * Some hw specific parts of this pmap were derived or influenced
30  * by NetBSD's ibm4xx pmap module. More generic code is shared with
31  * a few other pmap modules from the FreeBSD tree.
32  */
33 
34  /*
35   * VM layout notes:
36   *
37   * Kernel and user threads run within one common virtual address space
38   * defined by AS=0.
39   *
40   * 32-bit pmap:
41   * Virtual address space layout:
42   * -----------------------------
43   * 0x0000_0000 - 0x7fff_ffff	: user process
44   * 0x8000_0000 - 0xbfff_ffff	: pmap_mapdev()-ed area (PCI/PCIE etc.)
45   * 0xc000_0000 - 0xffff_efff	: KVA
46   */
47 
48 #include <sys/cdefs.h>
49 #include "opt_ddb.h"
50 #include "opt_kstack_pages.h"
51 
52 #include <sys/param.h>
53 #include <sys/conf.h>
54 #include <sys/malloc.h>
55 #include <sys/ktr.h>
56 #include <sys/proc.h>
57 #include <sys/user.h>
58 #include <sys/queue.h>
59 #include <sys/systm.h>
60 #include <sys/kernel.h>
61 #include <sys/kerneldump.h>
62 #include <sys/linker.h>
63 #include <sys/msgbuf.h>
64 #include <sys/lock.h>
65 #include <sys/mutex.h>
66 #include <sys/rwlock.h>
67 #include <sys/sched.h>
68 #include <sys/smp.h>
69 #include <sys/vmmeter.h>
70 
71 #include <vm/vm.h>
72 #include <vm/vm_page.h>
73 #include <vm/vm_kern.h>
74 #include <vm/vm_pageout.h>
75 #include <vm/vm_extern.h>
76 #include <vm/vm_object.h>
77 #include <vm/vm_param.h>
78 #include <vm/vm_map.h>
79 #include <vm/vm_pager.h>
80 #include <vm/vm_phys.h>
81 #include <vm/vm_pagequeue.h>
82 #include <vm/uma.h>
83 
84 #include <machine/_inttypes.h>
85 #include <machine/cpu.h>
86 #include <machine/pcb.h>
87 #include <machine/platform.h>
88 
89 #include <machine/tlb.h>
90 #include <machine/spr.h>
91 #include <machine/md_var.h>
92 #include <machine/mmuvar.h>
93 #include <machine/pmap.h>
94 #include <machine/pte.h>
95 
96 #include <ddb/ddb.h>
97 
98 #define	PRI0ptrX	"08x"
99 
100 /* Reserved KVA space and mutex for mmu_booke_zero_page. */
101 static vm_offset_t zero_page_va;
102 static struct mtx zero_page_mutex;
103 
104 /* Reserved KVA space and mutex for mmu_booke_copy_page. */
105 static vm_offset_t copy_page_src_va;
106 static vm_offset_t copy_page_dst_va;
107 static struct mtx copy_page_mutex;
108 
109 static vm_offset_t kernel_ptbl_root;
110 static unsigned int kernel_ptbls;	/* Number of KVA ptbls. */
111 
112 /**************************************************************************/
113 /* PMAP */
114 /**************************************************************************/
115 
116 #define	VM_MAPDEV_BASE	((vm_offset_t)VM_MAXUSER_ADDRESS + PAGE_SIZE)
117 
118 static void tid_flush(tlbtid_t tid);
119 
120 /**************************************************************************/
121 /* Page table management */
122 /**************************************************************************/
123 
124 #define PMAP_ROOT_SIZE	(sizeof(pte_t**) * PDIR_NENTRIES)
125 static void ptbl_init(void);
126 static struct ptbl_buf *ptbl_buf_alloc(void);
127 static void ptbl_buf_free(struct ptbl_buf *);
128 static void ptbl_free_pmap_ptbl(pmap_t, pte_t *);
129 
130 static pte_t *ptbl_alloc(pmap_t, unsigned int, bool);
131 static void ptbl_free(pmap_t, unsigned int);
132 static void ptbl_hold(pmap_t, unsigned int);
133 static int ptbl_unhold(pmap_t, unsigned int);
134 
135 static vm_paddr_t pte_vatopa(pmap_t, vm_offset_t);
136 static int pte_enter(pmap_t, vm_page_t, vm_offset_t, uint32_t, bool);
137 static int pte_remove(pmap_t, vm_offset_t, uint8_t);
138 static pte_t *pte_find(pmap_t, vm_offset_t);
139 
140 struct ptbl_buf {
141 	TAILQ_ENTRY(ptbl_buf) link;	/* list link */
142 	vm_offset_t kva;		/* va of mapping */
143 };
144 
145 /* Number of kva ptbl buffers, each covering one ptbl (PTBL_PAGES). */
146 #define PTBL_BUFS		(128 * 16)
147 
148 /* ptbl free list and a lock used for access synchronization. */
149 static TAILQ_HEAD(, ptbl_buf) ptbl_buf_freelist;
150 static struct mtx ptbl_buf_freelist_lock;
151 
152 /* Base address of kva space allocated fot ptbl bufs. */
153 static vm_offset_t ptbl_buf_pool_vabase;
154 
155 /* Pointer to ptbl_buf structures. */
156 static struct ptbl_buf *ptbl_bufs;
157 
158 /**************************************************************************/
159 /* Page table related */
160 /**************************************************************************/
161 
162 /* Initialize pool of kva ptbl buffers. */
163 static void
ptbl_init(void)164 ptbl_init(void)
165 {
166 	int i;
167 
168 	/* Create the UMA zone for page table roots. */
169 	ptbl_root_zone = uma_zcreate("pmap root", PMAP_ROOT_SIZE,
170 	    NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, UMA_ZONE_VM);
171 
172 	CTR3(KTR_PMAP, "%s: s (ptbl_bufs = 0x%08x size 0x%08x)", __func__,
173 	    (uint32_t)ptbl_bufs, sizeof(struct ptbl_buf) * PTBL_BUFS);
174 	CTR3(KTR_PMAP, "%s: s (ptbl_buf_pool_vabase = 0x%08x size = 0x%08x)",
175 	    __func__, ptbl_buf_pool_vabase, PTBL_BUFS * PTBL_PAGES * PAGE_SIZE);
176 
177 	mtx_init(&ptbl_buf_freelist_lock, "ptbl bufs lock", NULL, MTX_DEF);
178 	TAILQ_INIT(&ptbl_buf_freelist);
179 
180 	for (i = 0; i < PTBL_BUFS; i++) {
181 		ptbl_bufs[i].kva =
182 		    ptbl_buf_pool_vabase + i * PTBL_PAGES * PAGE_SIZE;
183 		TAILQ_INSERT_TAIL(&ptbl_buf_freelist, &ptbl_bufs[i], link);
184 	}
185 }
186 
187 /* Get a ptbl_buf from the freelist. */
188 static struct ptbl_buf *
ptbl_buf_alloc(void)189 ptbl_buf_alloc(void)
190 {
191 	struct ptbl_buf *buf;
192 
193 	mtx_lock(&ptbl_buf_freelist_lock);
194 	buf = TAILQ_FIRST(&ptbl_buf_freelist);
195 	if (buf != NULL)
196 		TAILQ_REMOVE(&ptbl_buf_freelist, buf, link);
197 	mtx_unlock(&ptbl_buf_freelist_lock);
198 
199 	CTR2(KTR_PMAP, "%s: buf = %p", __func__, buf);
200 
201 	return (buf);
202 }
203 
204 /* Return ptbl buff to free pool. */
205 static void
ptbl_buf_free(struct ptbl_buf * buf)206 ptbl_buf_free(struct ptbl_buf *buf)
207 {
208 
209 	CTR2(KTR_PMAP, "%s: buf = %p", __func__, buf);
210 
211 	mtx_lock(&ptbl_buf_freelist_lock);
212 	TAILQ_INSERT_TAIL(&ptbl_buf_freelist, buf, link);
213 	mtx_unlock(&ptbl_buf_freelist_lock);
214 }
215 
216 /*
217  * Search the list of allocated ptbl bufs and find on list of allocated ptbls
218  */
219 static void
ptbl_free_pmap_ptbl(pmap_t pmap,pte_t * ptbl)220 ptbl_free_pmap_ptbl(pmap_t pmap, pte_t *ptbl)
221 {
222 	struct ptbl_buf *pbuf;
223 
224 	CTR2(KTR_PMAP, "%s: ptbl = %p", __func__, ptbl);
225 
226 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
227 
228 	TAILQ_FOREACH(pbuf, &pmap->pm_ptbl_list, link)
229 		if (pbuf->kva == (vm_offset_t)ptbl) {
230 			/* Remove from pmap ptbl buf list. */
231 			TAILQ_REMOVE(&pmap->pm_ptbl_list, pbuf, link);
232 
233 			/* Free corresponding ptbl buf. */
234 			ptbl_buf_free(pbuf);
235 			break;
236 		}
237 }
238 
239 /* Allocate page table. */
240 static pte_t *
ptbl_alloc(pmap_t pmap,unsigned int pdir_idx,bool nosleep)241 ptbl_alloc(pmap_t pmap, unsigned int pdir_idx, bool nosleep)
242 {
243 	vm_page_t mtbl[PTBL_PAGES];
244 	vm_page_t m;
245 	struct ptbl_buf *pbuf;
246 	unsigned int pidx;
247 	pte_t *ptbl;
248 	int i, j;
249 
250 	CTR4(KTR_PMAP, "%s: pmap = %p su = %d pdir_idx = %d", __func__, pmap,
251 	    (pmap == kernel_pmap), pdir_idx);
252 
253 	KASSERT((pdir_idx <= (VM_MAXUSER_ADDRESS / PDIR_SIZE)),
254 	    ("ptbl_alloc: invalid pdir_idx"));
255 	KASSERT((pmap->pm_pdir[pdir_idx] == NULL),
256 	    ("pte_alloc: valid ptbl entry exists!"));
257 
258 	pbuf = ptbl_buf_alloc();
259 	if (pbuf == NULL)
260 		panic("pte_alloc: couldn't alloc kernel virtual memory");
261 
262 	ptbl = (pte_t *)pbuf->kva;
263 
264 	CTR2(KTR_PMAP, "%s: ptbl kva = %p", __func__, ptbl);
265 
266 	for (i = 0; i < PTBL_PAGES; i++) {
267 		pidx = (PTBL_PAGES * pdir_idx) + i;
268 		while ((m = vm_page_alloc_noobj(VM_ALLOC_WIRED)) == NULL) {
269 			if (nosleep) {
270 				ptbl_free_pmap_ptbl(pmap, ptbl);
271 				for (j = 0; j < i; j++)
272 					vm_page_free(mtbl[j]);
273 				vm_wire_sub(i);
274 				return (NULL);
275 			}
276 			PMAP_UNLOCK(pmap);
277 			rw_wunlock(&pvh_global_lock);
278 			vm_wait(NULL);
279 			rw_wlock(&pvh_global_lock);
280 			PMAP_LOCK(pmap);
281 		}
282 		m->pindex = pidx;
283 		mtbl[i] = m;
284 	}
285 
286 	/* Map allocated pages into kernel_pmap. */
287 	mmu_booke_qenter(ptbl, mtbl, PTBL_PAGES);
288 
289 	/* Zero whole ptbl. */
290 	bzero(ptbl, PTBL_PAGES * PAGE_SIZE);
291 
292 	/* Add pbuf to the pmap ptbl bufs list. */
293 	TAILQ_INSERT_TAIL(&pmap->pm_ptbl_list, pbuf, link);
294 
295 	return (ptbl);
296 }
297 
298 /* Free ptbl pages and invalidate pdir entry. */
299 static void
ptbl_free(pmap_t pmap,unsigned int pdir_idx)300 ptbl_free(pmap_t pmap, unsigned int pdir_idx)
301 {
302 	pte_t *ptbl;
303 	vm_paddr_t pa;
304 	vm_offset_t va;
305 	vm_page_t m;
306 	int i;
307 
308 	CTR4(KTR_PMAP, "%s: pmap = %p su = %d pdir_idx = %d", __func__, pmap,
309 	    (pmap == kernel_pmap), pdir_idx);
310 
311 	KASSERT((pdir_idx <= (VM_MAXUSER_ADDRESS / PDIR_SIZE)),
312 	    ("ptbl_free: invalid pdir_idx"));
313 
314 	ptbl = pmap->pm_pdir[pdir_idx];
315 
316 	CTR2(KTR_PMAP, "%s: ptbl = %p", __func__, ptbl);
317 
318 	KASSERT((ptbl != NULL), ("ptbl_free: null ptbl"));
319 
320 	/*
321 	 * Invalidate the pdir entry as soon as possible, so that other CPUs
322 	 * don't attempt to look up the page tables we are releasing.
323 	 */
324 	mtx_lock_spin(&tlbivax_mutex);
325 	tlb_miss_lock();
326 
327 	pmap->pm_pdir[pdir_idx] = NULL;
328 
329 	tlb_miss_unlock();
330 	mtx_unlock_spin(&tlbivax_mutex);
331 
332 	for (i = 0; i < PTBL_PAGES; i++) {
333 		va = ((vm_offset_t)ptbl + (i * PAGE_SIZE));
334 		pa = pte_vatopa(kernel_pmap, va);
335 		m = PHYS_TO_VM_PAGE(pa);
336 		vm_page_free_zero(m);
337 		vm_wire_sub(1);
338 		mmu_booke_kremove(va);
339 	}
340 
341 	ptbl_free_pmap_ptbl(pmap, ptbl);
342 }
343 
344 /*
345  * Decrement ptbl pages hold count and attempt to free ptbl pages.
346  * Called when removing pte entry from ptbl.
347  *
348  * Return 1 if ptbl pages were freed.
349  */
350 static int
ptbl_unhold(pmap_t pmap,unsigned int pdir_idx)351 ptbl_unhold(pmap_t pmap, unsigned int pdir_idx)
352 {
353 	pte_t *ptbl;
354 	vm_paddr_t pa;
355 	vm_page_t m;
356 	int i;
357 
358 	CTR4(KTR_PMAP, "%s: pmap = %p su = %d pdir_idx = %d", __func__, pmap,
359 	    (pmap == kernel_pmap), pdir_idx);
360 
361 	KASSERT((pdir_idx <= (VM_MAXUSER_ADDRESS / PDIR_SIZE)),
362 	    ("ptbl_unhold: invalid pdir_idx"));
363 	KASSERT((pmap != kernel_pmap),
364 	    ("ptbl_unhold: unholding kernel ptbl!"));
365 
366 	ptbl = pmap->pm_pdir[pdir_idx];
367 
368 	//debugf("ptbl_unhold: ptbl = 0x%08x\n", (u_int32_t)ptbl);
369 	KASSERT(((vm_offset_t)ptbl >= VM_MIN_KERNEL_ADDRESS),
370 	    ("ptbl_unhold: non kva ptbl"));
371 
372 	/* decrement hold count */
373 	for (i = 0; i < PTBL_PAGES; i++) {
374 		pa = pte_vatopa(kernel_pmap,
375 		    (vm_offset_t)ptbl + (i * PAGE_SIZE));
376 		m = PHYS_TO_VM_PAGE(pa);
377 		m->ref_count--;
378 	}
379 
380 	/*
381 	 * Free ptbl pages if there are no pte etries in this ptbl.
382 	 * ref_count has the same value for all ptbl pages, so check the last
383 	 * page.
384 	 */
385 	if (m->ref_count == 0) {
386 		ptbl_free(pmap, pdir_idx);
387 
388 		//debugf("ptbl_unhold: e (freed ptbl)\n");
389 		return (1);
390 	}
391 
392 	return (0);
393 }
394 
395 /*
396  * Increment hold count for ptbl pages. This routine is used when a new pte
397  * entry is being inserted into the ptbl.
398  */
399 static void
ptbl_hold(pmap_t pmap,unsigned int pdir_idx)400 ptbl_hold(pmap_t pmap, unsigned int pdir_idx)
401 {
402 	vm_paddr_t pa;
403 	pte_t *ptbl;
404 	vm_page_t m;
405 	int i;
406 
407 	CTR3(KTR_PMAP, "%s: pmap = %p pdir_idx = %d", __func__, pmap,
408 	    pdir_idx);
409 
410 	KASSERT((pdir_idx <= (VM_MAXUSER_ADDRESS / PDIR_SIZE)),
411 	    ("ptbl_hold: invalid pdir_idx"));
412 	KASSERT((pmap != kernel_pmap),
413 	    ("ptbl_hold: holding kernel ptbl!"));
414 
415 	ptbl = pmap->pm_pdir[pdir_idx];
416 
417 	KASSERT((ptbl != NULL), ("ptbl_hold: null ptbl"));
418 
419 	for (i = 0; i < PTBL_PAGES; i++) {
420 		pa = pte_vatopa(kernel_pmap,
421 		    (vm_offset_t)ptbl + (i * PAGE_SIZE));
422 		m = PHYS_TO_VM_PAGE(pa);
423 		m->ref_count++;
424 	}
425 }
426 
427 /*
428  * Clean pte entry, try to free page table page if requested.
429  *
430  * Return 1 if ptbl pages were freed, otherwise return 0.
431  */
432 static int
pte_remove(pmap_t pmap,vm_offset_t va,uint8_t flags)433 pte_remove(pmap_t pmap, vm_offset_t va, uint8_t flags)
434 {
435 	unsigned int pdir_idx = PDIR_IDX(va);
436 	unsigned int ptbl_idx = PTBL_IDX(va);
437 	vm_page_t m;
438 	pte_t *ptbl;
439 	pte_t *pte;
440 
441 	//int su = (pmap == kernel_pmap);
442 	//debugf("pte_remove: s (su = %d pmap = 0x%08x va = 0x%08x flags = %d)\n",
443 	//		su, (u_int32_t)pmap, va, flags);
444 
445 	ptbl = pmap->pm_pdir[pdir_idx];
446 	KASSERT(ptbl, ("pte_remove: null ptbl"));
447 
448 	pte = &ptbl[ptbl_idx];
449 
450 	if (pte == NULL || !PTE_ISVALID(pte))
451 		return (0);
452 
453 	if (PTE_ISWIRED(pte))
454 		pmap->pm_stats.wired_count--;
455 
456 	/* Get vm_page_t for mapped pte. */
457 	m = PHYS_TO_VM_PAGE(PTE_PA(pte));
458 
459 	/* Handle managed entry. */
460 	if (PTE_ISMANAGED(pte)) {
461 		if (PTE_ISMODIFIED(pte))
462 			vm_page_dirty(m);
463 
464 		if (PTE_ISREFERENCED(pte))
465 			vm_page_aflag_set(m, PGA_REFERENCED);
466 
467 		pv_remove(pmap, va, m);
468 	} else if (pmap == kernel_pmap && m && m->md.pv_tracked) {
469 		/*
470 		 * Always pv_insert()/pv_remove() on MPC85XX, in case DPAA is
471 		 * used.  This is needed by the NCSW support code for fast
472 		 * VA<->PA translation.
473 		 */
474 		pv_remove(pmap, va, m);
475 		if (TAILQ_EMPTY(&m->md.pv_list))
476 			m->md.pv_tracked = false;
477 	}
478 
479 	mtx_lock_spin(&tlbivax_mutex);
480 	tlb_miss_lock();
481 
482 	tlb0_flush_entry(va);
483 	*pte = 0;
484 
485 	tlb_miss_unlock();
486 	mtx_unlock_spin(&tlbivax_mutex);
487 
488 	pmap->pm_stats.resident_count--;
489 
490 	if (flags & PTBL_UNHOLD) {
491 		//debugf("pte_remove: e (unhold)\n");
492 		return (ptbl_unhold(pmap, pdir_idx));
493 	}
494 
495 	//debugf("pte_remove: e\n");
496 	return (0);
497 }
498 
499 /*
500  * Insert PTE for a given page and virtual address.
501  */
502 static int
pte_enter(pmap_t pmap,vm_page_t m,vm_offset_t va,uint32_t flags,bool nosleep)503 pte_enter(pmap_t pmap, vm_page_t m, vm_offset_t va, uint32_t flags,
504     bool nosleep)
505 {
506 	unsigned int pdir_idx = PDIR_IDX(va);
507 	unsigned int ptbl_idx = PTBL_IDX(va);
508 	pte_t *ptbl, *pte, pte_tmp;
509 
510 	CTR4(KTR_PMAP, "%s: su = %d pmap = %p va = %p", __func__,
511 	    pmap == kernel_pmap, pmap, va);
512 
513 	/* Get the page table pointer. */
514 	ptbl = pmap->pm_pdir[pdir_idx];
515 
516 	if (ptbl == NULL) {
517 		/* Allocate page table pages. */
518 		ptbl = ptbl_alloc(pmap, pdir_idx, nosleep);
519 		if (ptbl == NULL) {
520 			KASSERT(nosleep, ("nosleep and NULL ptbl"));
521 			return (ENOMEM);
522 		}
523 		pmap->pm_pdir[pdir_idx] = ptbl;
524 		pte = &ptbl[ptbl_idx];
525 	} else {
526 		/*
527 		 * Check if there is valid mapping for requested
528 		 * va, if there is, remove it.
529 		 */
530 		pte = &pmap->pm_pdir[pdir_idx][ptbl_idx];
531 		if (PTE_ISVALID(pte)) {
532 			pte_remove(pmap, va, PTBL_HOLD);
533 		} else {
534 			/*
535 			 * pte is not used, increment hold count
536 			 * for ptbl pages.
537 			 */
538 			if (pmap != kernel_pmap)
539 				ptbl_hold(pmap, pdir_idx);
540 		}
541 	}
542 
543 	/*
544 	 * Insert pv_entry into pv_list for mapped page if part of managed
545 	 * memory.
546 	 */
547 	if ((m->oflags & VPO_UNMANAGED) == 0) {
548 		flags |= PTE_MANAGED;
549 
550 		/* Create and insert pv entry. */
551 		pv_insert(pmap, va, m);
552 	}
553 
554 	pmap->pm_stats.resident_count++;
555 
556 	pte_tmp = PTE_RPN_FROM_PA(VM_PAGE_TO_PHYS(m));
557 	pte_tmp |= (PTE_VALID | flags | PTE_PS_4KB); /* 4KB pages only */
558 
559 	mtx_lock_spin(&tlbivax_mutex);
560 	tlb_miss_lock();
561 
562 	tlb0_flush_entry(va);
563 	*pte = pte_tmp;
564 
565 	tlb_miss_unlock();
566 	mtx_unlock_spin(&tlbivax_mutex);
567 	return (0);
568 }
569 
570 /* Return the pa for the given pmap/va. */
571 static vm_paddr_t
pte_vatopa(pmap_t pmap,vm_offset_t va)572 pte_vatopa(pmap_t pmap, vm_offset_t va)
573 {
574 	vm_paddr_t pa = 0;
575 	pte_t *pte;
576 
577 	pte = pte_find(pmap, va);
578 	if ((pte != NULL) && PTE_ISVALID(pte))
579 		pa = (PTE_PA(pte) | (va & PTE_PA_MASK));
580 	return (pa);
581 }
582 
583 /* Get a pointer to a PTE in a page table. */
584 static pte_t *
pte_find(pmap_t pmap,vm_offset_t va)585 pte_find(pmap_t pmap, vm_offset_t va)
586 {
587 	unsigned int pdir_idx = PDIR_IDX(va);
588 	unsigned int ptbl_idx = PTBL_IDX(va);
589 
590 	KASSERT((pmap != NULL), ("pte_find: invalid pmap"));
591 
592 	if (pmap->pm_pdir[pdir_idx])
593 		return (&(pmap->pm_pdir[pdir_idx][ptbl_idx]));
594 
595 	return (NULL);
596 }
597 
598 /* Get a pointer to a PTE in a page table, or the next closest (greater) one. */
599 static __inline pte_t *
pte_find_next(pmap_t pmap,vm_offset_t * pva)600 pte_find_next(pmap_t pmap, vm_offset_t *pva)
601 {
602 	vm_offset_t	va;
603 	pte_t	      **pdir;
604 	pte_t	       *pte;
605 	unsigned long	i, j;
606 
607 	KASSERT((pmap != NULL), ("pte_find: invalid pmap"));
608 
609 	va = *pva;
610 	i = PDIR_IDX(va);
611 	j = PTBL_IDX(va);
612 	pdir = pmap->pm_pdir;
613 	for (; i < PDIR_NENTRIES; i++, j = 0) {
614 		if (pdir[i] == NULL)
615 			continue;
616 		for (; j < PTBL_NENTRIES; j++) {
617 			pte = &pdir[i][j];
618 			if (!PTE_ISVALID(pte))
619 				continue;
620 			*pva = PDIR_SIZE * i + PAGE_SIZE * j;
621 			return (pte);
622 		}
623 	}
624 	return (NULL);
625 }
626 
627 /* Set up kernel page tables. */
628 static void
kernel_pte_alloc(vm_offset_t data_end,vm_offset_t addr)629 kernel_pte_alloc(vm_offset_t data_end, vm_offset_t addr)
630 {
631 	pte_t		*pte;
632 	vm_offset_t	va;
633 	vm_offset_t	pdir_start;
634 	int		i;
635 
636 	kptbl_min = VM_MIN_KERNEL_ADDRESS / PDIR_SIZE;
637 	kernel_pmap->pm_pdir = (pte_t **)kernel_ptbl_root;
638 
639 	pdir_start = kernel_ptbl_root + PDIR_NENTRIES * sizeof(pte_t);
640 
641 	/* Initialize kernel pdir */
642 	for (i = 0; i < kernel_ptbls; i++) {
643 		kernel_pmap->pm_pdir[kptbl_min + i] =
644 		    (pte_t *)(pdir_start + (i * PAGE_SIZE * PTBL_PAGES));
645 	}
646 
647 	/*
648 	 * Fill in PTEs covering kernel code and data. They are not required
649 	 * for address translation, as this area is covered by static TLB1
650 	 * entries, but for pte_vatopa() to work correctly with kernel area
651 	 * addresses.
652 	 */
653 	for (va = addr; va < data_end; va += PAGE_SIZE) {
654 		pte = &(kernel_pmap->pm_pdir[PDIR_IDX(va)][PTBL_IDX(va)]);
655 		powerpc_sync();
656 		*pte = PTE_RPN_FROM_PA(kernload + (va - kernstart));
657 		*pte |= PTE_M | PTE_SR | PTE_SW | PTE_SX | PTE_WIRED |
658 		    PTE_VALID | PTE_PS_4KB;
659 	}
660 }
661 
662 static vm_offset_t
mmu_booke_alloc_kernel_pgtables(vm_offset_t data_end)663 mmu_booke_alloc_kernel_pgtables(vm_offset_t data_end)
664 {
665 	/* Allocate space for ptbl_bufs. */
666 	ptbl_bufs = (struct ptbl_buf *)data_end;
667 	data_end += sizeof(struct ptbl_buf) * PTBL_BUFS;
668 	debugf(" ptbl_bufs at 0x%"PRI0ptrX" end = 0x%"PRI0ptrX"\n",
669 	    (uintptr_t)ptbl_bufs, data_end);
670 
671 	data_end = round_page(data_end);
672 
673 	kernel_ptbl_root = data_end;
674 	data_end += PDIR_NENTRIES * sizeof(pte_t*);
675 
676 	/* Allocate PTE tables for kernel KVA. */
677 	kernel_ptbls = howmany(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS,
678 	    PDIR_SIZE);
679 	data_end += kernel_ptbls * PTBL_PAGES * PAGE_SIZE;
680 	debugf(" kernel ptbls: %d\n", kernel_ptbls);
681 	debugf(" kernel pdir at %#jx end = %#jx\n",
682 	    (uintmax_t)kernel_ptbl_root, (uintmax_t)data_end);
683 
684 	return (data_end);
685 }
686 
687 /*
688  * Initialize a preallocated and zeroed pmap structure,
689  * such as one in a vmspace structure.
690  */
691 static int
mmu_booke_pinit(pmap_t pmap)692 mmu_booke_pinit(pmap_t pmap)
693 {
694 	int i;
695 
696 	CTR4(KTR_PMAP, "%s: pmap = %p, proc %d '%s'", __func__, pmap,
697 	    curthread->td_proc->p_pid, curthread->td_proc->p_comm);
698 
699 	KASSERT((pmap != kernel_pmap), ("pmap_pinit: initializing kernel_pmap"));
700 
701 	for (i = 0; i < MAXCPU; i++)
702 		pmap->pm_tid[i] = TID_NONE;
703 	CPU_ZERO(&kernel_pmap->pm_active);
704 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
705 	pmap->pm_pdir = uma_zalloc(ptbl_root_zone, M_WAITOK);
706 	bzero(pmap->pm_pdir, sizeof(pte_t *) * PDIR_NENTRIES);
707 	TAILQ_INIT(&pmap->pm_ptbl_list);
708 
709 	return (1);
710 }
711 
712 /*
713  * Release any resources held by the given physical map.
714  * Called when a pmap initialized by mmu_booke_pinit is being released.
715  * Should only be called if the map contains no valid mappings.
716  */
717 static void
mmu_booke_release(pmap_t pmap)718 mmu_booke_release(pmap_t pmap)
719 {
720 
721 	KASSERT(pmap->pm_stats.resident_count == 0,
722 	    ("pmap_release: pmap resident count %ld != 0",
723 	    pmap->pm_stats.resident_count));
724 	uma_zfree(ptbl_root_zone, pmap->pm_pdir);
725 }
726 
727 static void
mmu_booke_sync_icache(pmap_t pm,vm_offset_t va,vm_size_t sz)728 mmu_booke_sync_icache(pmap_t pm, vm_offset_t va, vm_size_t sz)
729 {
730 	pte_t *pte;
731 	vm_paddr_t pa = 0;
732 	int sync_sz, valid;
733 	pmap_t pmap;
734 	vm_page_t m;
735 	vm_offset_t addr;
736 	int active;
737 
738 	rw_wlock(&pvh_global_lock);
739 	pmap = PCPU_GET(curpmap);
740 	active = (pm == kernel_pmap || pm == pmap) ? 1 : 0;
741 	while (sz > 0) {
742 		PMAP_LOCK(pm);
743 		pte = pte_find(pm, va);
744 		valid = (pte != NULL && PTE_ISVALID(pte)) ? 1 : 0;
745 		if (valid)
746 			pa = PTE_PA(pte);
747 		PMAP_UNLOCK(pm);
748 		sync_sz = PAGE_SIZE - (va & PAGE_MASK);
749 		sync_sz = min(sync_sz, sz);
750 		if (valid) {
751 			if (!active) {
752 				/*
753 				 * Create a mapping in the active pmap.
754 				 *
755 				 * XXX: We use the zero page here, because
756 				 * it isn't likely to be in use.
757 				 * If we ever decide to support
758 				 * security.bsd.map_at_zero on Book-E, change
759 				 * this to some other address that isn't
760 				 * normally mappable.
761 				 */
762 				addr = 0;
763 				m = PHYS_TO_VM_PAGE(pa);
764 				PMAP_LOCK(pmap);
765 				pte_enter(pmap, m, addr,
766 				    PTE_SR | PTE_VALID, false);
767 				__syncicache((void *)(addr + (va & PAGE_MASK)),
768 				    sync_sz);
769 				pte_remove(pmap, addr, PTBL_UNHOLD);
770 				PMAP_UNLOCK(pmap);
771 			} else
772 				__syncicache((void *)va, sync_sz);
773 		}
774 		va += sync_sz;
775 		sz -= sync_sz;
776 	}
777 	rw_wunlock(&pvh_global_lock);
778 }
779 
780 /*
781  * mmu_booke_zero_page_area zeros the specified hardware page by
782  * mapping it into virtual memory and using bzero to clear
783  * its contents.
784  *
785  * off and size must reside within a single page.
786  */
787 static void
mmu_booke_zero_page_area(vm_page_t m,int off,int size)788 mmu_booke_zero_page_area(vm_page_t m, int off, int size)
789 {
790 	vm_offset_t va;
791 
792 	/* XXX KASSERT off and size are within a single page? */
793 
794 	mtx_lock(&zero_page_mutex);
795 	va = zero_page_va;
796 
797 	mmu_booke_kenter(va, VM_PAGE_TO_PHYS(m));
798 	bzero((caddr_t)va + off, size);
799 	mmu_booke_kremove(va);
800 
801 	mtx_unlock(&zero_page_mutex);
802 }
803 
804 /*
805  * mmu_booke_zero_page zeros the specified hardware page.
806  */
807 static void
mmu_booke_zero_page(vm_page_t m)808 mmu_booke_zero_page(vm_page_t m)
809 {
810 	vm_offset_t va;
811 
812 	va = zero_page_va;
813 	mtx_lock(&zero_page_mutex);
814 
815 	mmu_booke_kenter(va, VM_PAGE_TO_PHYS(m));
816 
817 	bzero((void *)va, PAGE_SIZE);
818 
819 	mmu_booke_kremove(va);
820 
821 	mtx_unlock(&zero_page_mutex);
822 }
823 
824 /*
825  * mmu_booke_copy_page copies the specified (machine independent) page by
826  * mapping the page into virtual memory and using memcopy to copy the page,
827  * one machine dependent page at a time.
828  */
829 static void
mmu_booke_copy_page(vm_page_t sm,vm_page_t dm)830 mmu_booke_copy_page(vm_page_t sm, vm_page_t dm)
831 {
832 	vm_offset_t sva, dva;
833 
834 	sva = copy_page_src_va;
835 	dva = copy_page_dst_va;
836 
837 	mtx_lock(&copy_page_mutex);
838 	mmu_booke_kenter(sva, VM_PAGE_TO_PHYS(sm));
839 	mmu_booke_kenter(dva, VM_PAGE_TO_PHYS(dm));
840 
841 	memcpy((caddr_t)dva, (caddr_t)sva, PAGE_SIZE);
842 
843 	mmu_booke_kremove(dva);
844 	mmu_booke_kremove(sva);
845 	mtx_unlock(&copy_page_mutex);
846 }
847 
848 static inline void
mmu_booke_copy_pages(vm_page_t * ma,vm_offset_t a_offset,vm_page_t * mb,vm_offset_t b_offset,int xfersize)849 mmu_booke_copy_pages(vm_page_t *ma, vm_offset_t a_offset,
850     vm_page_t *mb, vm_offset_t b_offset, int xfersize)
851 {
852 	void *a_cp, *b_cp;
853 	vm_offset_t a_pg_offset, b_pg_offset;
854 	int cnt;
855 
856 	mtx_lock(&copy_page_mutex);
857 	while (xfersize > 0) {
858 		a_pg_offset = a_offset & PAGE_MASK;
859 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
860 		mmu_booke_kenter(copy_page_src_va,
861 		    VM_PAGE_TO_PHYS(ma[a_offset >> PAGE_SHIFT]));
862 		a_cp = (char *)copy_page_src_va + a_pg_offset;
863 		b_pg_offset = b_offset & PAGE_MASK;
864 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
865 		mmu_booke_kenter(copy_page_dst_va,
866 		    VM_PAGE_TO_PHYS(mb[b_offset >> PAGE_SHIFT]));
867 		b_cp = (char *)copy_page_dst_va + b_pg_offset;
868 		bcopy(a_cp, b_cp, cnt);
869 		mmu_booke_kremove(copy_page_dst_va);
870 		mmu_booke_kremove(copy_page_src_va);
871 		a_offset += cnt;
872 		b_offset += cnt;
873 		xfersize -= cnt;
874 	}
875 	mtx_unlock(&copy_page_mutex);
876 }
877 
878 static void *
mmu_booke_quick_enter_page(vm_page_t m)879 mmu_booke_quick_enter_page(vm_page_t m)
880 {
881 	vm_paddr_t paddr;
882 	void *qaddr;
883 	uint32_t flags;
884 	pte_t *pte;
885 
886 	paddr = VM_PAGE_TO_PHYS(m);
887 
888 	flags = PTE_SR | PTE_SW | PTE_SX | PTE_WIRED | PTE_VALID;
889 	flags |= tlb_calc_wimg(paddr, pmap_page_get_memattr(m)) << PTE_MAS2_SHIFT;
890 	flags |= PTE_PS_4KB;
891 
892 	critical_enter();
893 	qaddr = PCPU_GET(qmap_addr);
894 
895 	pte = pte_find(kernel_pmap, (vm_offset_t)qaddr);
896 
897 	KASSERT(*pte == 0, ("mmu_booke_quick_enter_page: PTE busy"));
898 
899 	/*
900 	 * XXX: tlbivax is broadcast to other cores, but qaddr should
901  	 * not be present in other TLBs.  Is there a better instruction
902 	 * sequence to use? Or just forget it & use mmu_booke_kenter()...
903 	 */
904 	__asm __volatile("tlbivax 0, %0" ::
905 			 "r" ((vm_offset_t)qaddr & MAS2_EPN_MASK));
906 	__asm __volatile("isync; msync");
907 
908 	*pte = PTE_RPN_FROM_PA(paddr) | flags;
909 
910 	/* Flush the real memory from the instruction cache. */
911 	if ((flags & (PTE_I | PTE_G)) == 0)
912 		__syncicache(qaddr, PAGE_SIZE);
913 
914 	return (qaddr);
915 }
916 
917 static void
mmu_booke_quick_remove_page(void * addr)918 mmu_booke_quick_remove_page(void *addr)
919 {
920 	pte_t *pte;
921 
922 	pte = pte_find(kernel_pmap, (vm_offset_t)addr);
923 
924 	KASSERT(PCPU_GET(qmap_addr) == addr,
925 	    ("mmu_booke_quick_remove_page: invalid address"));
926 	KASSERT(*pte != 0,
927 	    ("mmu_booke_quick_remove_page: PTE not in use"));
928 
929 	*pte = 0;
930 	critical_exit();
931 }
932 
933 /**************************************************************************/
934 /* TID handling */
935 /**************************************************************************/
936 
937 /*
938  * Invalidate all TLB0 entries which match the given TID. Note this is
939  * dedicated for cases when invalidations should NOT be propagated to other
940  * CPUs.
941  */
942 static void
tid_flush(tlbtid_t tid)943 tid_flush(tlbtid_t tid)
944 {
945 	register_t msr;
946 
947 	/* Don't evict kernel translations */
948 	if (tid == TID_KERNEL)
949 		return;
950 
951 	msr = mfmsr();
952 	__asm __volatile("wrteei 0");
953 
954 	/*
955 	 * Newer (e500mc and later) have tlbilx, which doesn't broadcast, so use
956 	 * it for PID invalidation.
957 	 */
958 	switch ((mfpvr() >> 16) & 0xffff) {
959 	case FSL_E500mc:
960 	case FSL_E5500:
961 	case FSL_E6500:
962 		mtspr(SPR_MAS6, tid << MAS6_SPID0_SHIFT);
963 		/* tlbilxpid */
964 		__asm __volatile("isync; .long 0x7c200024; isync; msync");
965 		__asm __volatile("wrtee %0" :: "r"(msr));
966 		return;
967 	}
968 	/* Flash invalidate TLB0 instead of walking the TLB to invalidate. */
969 	mtspr(SPR_MMUCSR0, MMUCSR0_L2TLB0_FI);
970 
971 	__asm __volatile("wrtee %0" :: "r"(msr));
972 }
973