xref: /freebsd/sys/powerpc/booke/pmap_32.c (revision 45b69dd6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
50 
51 #include "opt_ddb.h"
52 #include "opt_kstack_pages.h"
53 
54 #include <sys/param.h>
55 #include <sys/conf.h>
56 #include <sys/malloc.h>
57 #include <sys/ktr.h>
58 #include <sys/proc.h>
59 #include <sys/user.h>
60 #include <sys/queue.h>
61 #include <sys/systm.h>
62 #include <sys/kernel.h>
63 #include <sys/kerneldump.h>
64 #include <sys/linker.h>
65 #include <sys/msgbuf.h>
66 #include <sys/lock.h>
67 #include <sys/mutex.h>
68 #include <sys/rwlock.h>
69 #include <sys/sched.h>
70 #include <sys/smp.h>
71 #include <sys/vmmeter.h>
72 
73 #include <vm/vm.h>
74 #include <vm/vm_page.h>
75 #include <vm/vm_kern.h>
76 #include <vm/vm_pageout.h>
77 #include <vm/vm_extern.h>
78 #include <vm/vm_object.h>
79 #include <vm/vm_param.h>
80 #include <vm/vm_map.h>
81 #include <vm/vm_pager.h>
82 #include <vm/vm_phys.h>
83 #include <vm/vm_pagequeue.h>
84 #include <vm/uma.h>
85 
86 #include <machine/_inttypes.h>
87 #include <machine/cpu.h>
88 #include <machine/pcb.h>
89 #include <machine/platform.h>
90 
91 #include <machine/tlb.h>
92 #include <machine/spr.h>
93 #include <machine/md_var.h>
94 #include <machine/mmuvar.h>
95 #include <machine/pmap.h>
96 #include <machine/pte.h>
97 
98 #include <ddb/ddb.h>
99 
100 #define	PRI0ptrX	"08x"
101 
102 /* Reserved KVA space and mutex for mmu_booke_zero_page. */
103 static vm_offset_t zero_page_va;
104 static struct mtx zero_page_mutex;
105 
106 /* Reserved KVA space and mutex for mmu_booke_copy_page. */
107 static vm_offset_t copy_page_src_va;
108 static vm_offset_t copy_page_dst_va;
109 static struct mtx copy_page_mutex;
110 
111 static vm_offset_t kernel_ptbl_root;
112 static unsigned int kernel_ptbls;	/* Number of KVA ptbls. */
113 
114 /**************************************************************************/
115 /* PMAP */
116 /**************************************************************************/
117 
118 #define	VM_MAPDEV_BASE	((vm_offset_t)VM_MAXUSER_ADDRESS + PAGE_SIZE)
119 
120 static void tid_flush(tlbtid_t tid);
121 static unsigned long ilog2(unsigned long);
122 
123 /**************************************************************************/
124 /* Page table management */
125 /**************************************************************************/
126 
127 #define PMAP_ROOT_SIZE	(sizeof(pte_t**) * PDIR_NENTRIES)
128 static void ptbl_init(void);
129 static struct ptbl_buf *ptbl_buf_alloc(void);
130 static void ptbl_buf_free(struct ptbl_buf *);
131 static void ptbl_free_pmap_ptbl(pmap_t, pte_t *);
132 
133 static pte_t *ptbl_alloc(pmap_t, unsigned int, boolean_t);
134 static void ptbl_free(pmap_t, unsigned int);
135 static void ptbl_hold(pmap_t, unsigned int);
136 static int ptbl_unhold(pmap_t, unsigned int);
137 
138 static vm_paddr_t pte_vatopa(pmap_t, vm_offset_t);
139 static int pte_enter(pmap_t, vm_page_t, vm_offset_t, uint32_t, boolean_t);
140 static int pte_remove(pmap_t, vm_offset_t, uint8_t);
141 static pte_t *pte_find(pmap_t, vm_offset_t);
142 
143 struct ptbl_buf {
144 	TAILQ_ENTRY(ptbl_buf) link;	/* list link */
145 	vm_offset_t kva;		/* va of mapping */
146 };
147 
148 /* Number of kva ptbl buffers, each covering one ptbl (PTBL_PAGES). */
149 #define PTBL_BUFS		(128 * 16)
150 
151 /* ptbl free list and a lock used for access synchronization. */
152 static TAILQ_HEAD(, ptbl_buf) ptbl_buf_freelist;
153 static struct mtx ptbl_buf_freelist_lock;
154 
155 /* Base address of kva space allocated fot ptbl bufs. */
156 static vm_offset_t ptbl_buf_pool_vabase;
157 
158 /* Pointer to ptbl_buf structures. */
159 static struct ptbl_buf *ptbl_bufs;
160 
161 /**************************************************************************/
162 /* Page table related */
163 /**************************************************************************/
164 
165 
166 /* Initialize pool of kva ptbl buffers. */
167 static void
168 ptbl_init(void)
169 {
170 	int i;
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 *
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
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
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 *
241 ptbl_alloc(pmap_t pmap, unsigned int pdir_idx, boolean_t 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(NULL, pidx,
269 		    VM_ALLOC_NOOBJ | VM_ALLOC_WIRED)) == NULL) {
270 			if (nosleep) {
271 				ptbl_free_pmap_ptbl(pmap, ptbl);
272 				for (j = 0; j < i; j++)
273 					vm_page_free(mtbl[j]);
274 				vm_wire_sub(i);
275 				return (NULL);
276 			}
277 			PMAP_UNLOCK(pmap);
278 			rw_wunlock(&pvh_global_lock);
279 			vm_wait(NULL);
280 			rw_wlock(&pvh_global_lock);
281 			PMAP_LOCK(pmap);
282 		}
283 		mtbl[i] = m;
284 	}
285 
286 	/* Map allocated pages into kernel_pmap. */
287 	mmu_booke_qenter((vm_offset_t)ptbl, mtbl, PTBL_PAGES);
288 
289 	/* Zero whole ptbl. */
290 	bzero((caddr_t)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
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
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
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
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 
462 		if (PTE_ISMODIFIED(pte))
463 			vm_page_dirty(m);
464 
465 		if (PTE_ISREFERENCED(pte))
466 			vm_page_aflag_set(m, PGA_REFERENCED);
467 
468 		pv_remove(pmap, va, m);
469 	} else if (pmap == kernel_pmap && m && m->md.pv_tracked) {
470 		/*
471 		 * Always pv_insert()/pv_remove() on MPC85XX, in case DPAA is
472 		 * used.  This is needed by the NCSW support code for fast
473 		 * VA<->PA translation.
474 		 */
475 		pv_remove(pmap, va, m);
476 		if (TAILQ_EMPTY(&m->md.pv_list))
477 			m->md.pv_tracked = false;
478 	}
479 
480 	mtx_lock_spin(&tlbivax_mutex);
481 	tlb_miss_lock();
482 
483 	tlb0_flush_entry(va);
484 	*pte = 0;
485 
486 	tlb_miss_unlock();
487 	mtx_unlock_spin(&tlbivax_mutex);
488 
489 	pmap->pm_stats.resident_count--;
490 
491 	if (flags & PTBL_UNHOLD) {
492 		//debugf("pte_remove: e (unhold)\n");
493 		return (ptbl_unhold(pmap, pdir_idx));
494 	}
495 
496 	//debugf("pte_remove: e\n");
497 	return (0);
498 }
499 
500 /*
501  * Insert PTE for a given page and virtual address.
502  */
503 static int
504 pte_enter(pmap_t pmap, vm_page_t m, vm_offset_t va, uint32_t flags,
505     boolean_t nosleep)
506 {
507 	unsigned int pdir_idx = PDIR_IDX(va);
508 	unsigned int ptbl_idx = PTBL_IDX(va);
509 	pte_t *ptbl, *pte, pte_tmp;
510 
511 	CTR4(KTR_PMAP, "%s: su = %d pmap = %p va = %p", __func__,
512 	    pmap == kernel_pmap, pmap, va);
513 
514 	/* Get the page table pointer. */
515 	ptbl = pmap->pm_pdir[pdir_idx];
516 
517 	if (ptbl == NULL) {
518 		/* Allocate page table pages. */
519 		ptbl = ptbl_alloc(pmap, pdir_idx, nosleep);
520 		if (ptbl == NULL) {
521 			KASSERT(nosleep, ("nosleep and NULL ptbl"));
522 			return (ENOMEM);
523 		}
524 		pmap->pm_pdir[pdir_idx] = ptbl;
525 		pte = &ptbl[ptbl_idx];
526 	} else {
527 		/*
528 		 * Check if there is valid mapping for requested
529 		 * va, if there is, remove it.
530 		 */
531 		pte = &pmap->pm_pdir[pdir_idx][ptbl_idx];
532 		if (PTE_ISVALID(pte)) {
533 			pte_remove(pmap, va, PTBL_HOLD);
534 		} else {
535 			/*
536 			 * pte is not used, increment hold count
537 			 * for ptbl pages.
538 			 */
539 			if (pmap != kernel_pmap)
540 				ptbl_hold(pmap, pdir_idx);
541 		}
542 	}
543 
544 	/*
545 	 * Insert pv_entry into pv_list for mapped page if part of managed
546 	 * memory.
547 	 */
548 	if ((m->oflags & VPO_UNMANAGED) == 0) {
549 		flags |= PTE_MANAGED;
550 
551 		/* Create and insert pv entry. */
552 		pv_insert(pmap, va, m);
553 	}
554 
555 	pmap->pm_stats.resident_count++;
556 
557 	pte_tmp = PTE_RPN_FROM_PA(VM_PAGE_TO_PHYS(m));
558 	pte_tmp |= (PTE_VALID | flags | PTE_PS_4KB); /* 4KB pages only */
559 
560 	mtx_lock_spin(&tlbivax_mutex);
561 	tlb_miss_lock();
562 
563 	tlb0_flush_entry(va);
564 	*pte = pte_tmp;
565 
566 	tlb_miss_unlock();
567 	mtx_unlock_spin(&tlbivax_mutex);
568 	return (0);
569 }
570 
571 /* Return the pa for the given pmap/va. */
572 static vm_paddr_t
573 pte_vatopa(pmap_t pmap, vm_offset_t va)
574 {
575 	vm_paddr_t pa = 0;
576 	pte_t *pte;
577 
578 	pte = pte_find(pmap, va);
579 	if ((pte != NULL) && PTE_ISVALID(pte))
580 		pa = (PTE_PA(pte) | (va & PTE_PA_MASK));
581 	return (pa);
582 }
583 
584 /* Get a pointer to a PTE in a page table. */
585 static pte_t *
586 pte_find(pmap_t pmap, vm_offset_t va)
587 {
588 	unsigned int pdir_idx = PDIR_IDX(va);
589 	unsigned int ptbl_idx = PTBL_IDX(va);
590 
591 	KASSERT((pmap != NULL), ("pte_find: invalid pmap"));
592 
593 	if (pmap->pm_pdir[pdir_idx])
594 		return (&(pmap->pm_pdir[pdir_idx][ptbl_idx]));
595 
596 	return (NULL);
597 }
598 
599 /* Get a pointer to a PTE in a page table, or the next closest (greater) one. */
600 static __inline pte_t *
601 pte_find_next(pmap_t pmap, vm_offset_t *pva)
602 {
603 	vm_offset_t	va;
604 	pte_t	      **pdir;
605 	pte_t	       *pte;
606 	unsigned long	i, j;
607 
608 	KASSERT((pmap != NULL), ("pte_find: invalid pmap"));
609 
610 	va = *pva;
611 	i = PDIR_IDX(va);
612 	j = PTBL_IDX(va);
613 	pdir = pmap->pm_pdir;
614 	for (; i < PDIR_NENTRIES; i++, j = 0) {
615 		if (pdir[i] == NULL)
616 			continue;
617 		for (; j < PTBL_NENTRIES; j++) {
618 			pte = &pdir[i][j];
619 			if (!PTE_ISVALID(pte))
620 				continue;
621 			*pva = PDIR_SIZE * i + PAGE_SIZE * j;
622 			return (pte);
623 		}
624 	}
625 	return (NULL);
626 }
627 
628 /* Set up kernel page tables. */
629 static void
630 kernel_pte_alloc(vm_offset_t data_end, vm_offset_t addr)
631 {
632 	pte_t		*pte;
633 	vm_offset_t	va;
634 	vm_offset_t	pdir_start;
635 	int		i;
636 
637 	kptbl_min = VM_MIN_KERNEL_ADDRESS / PDIR_SIZE;
638 	kernel_pmap->pm_pdir = (pte_t **)kernel_ptbl_root;
639 
640 	pdir_start = kernel_ptbl_root + PDIR_NENTRIES * sizeof(pte_t);
641 
642 	/* Initialize kernel pdir */
643 	for (i = 0; i < kernel_ptbls; i++) {
644 		kernel_pmap->pm_pdir[kptbl_min + i] =
645 		    (pte_t *)(pdir_start + (i * PAGE_SIZE * PTBL_PAGES));
646 	}
647 
648 	/*
649 	 * Fill in PTEs covering kernel code and data. They are not required
650 	 * for address translation, as this area is covered by static TLB1
651 	 * entries, but for pte_vatopa() to work correctly with kernel area
652 	 * addresses.
653 	 */
654 	for (va = addr; va < data_end; va += PAGE_SIZE) {
655 		pte = &(kernel_pmap->pm_pdir[PDIR_IDX(va)][PTBL_IDX(va)]);
656 		powerpc_sync();
657 		*pte = PTE_RPN_FROM_PA(kernload + (va - kernstart));
658 		*pte |= PTE_M | PTE_SR | PTE_SW | PTE_SX | PTE_WIRED |
659 		    PTE_VALID | PTE_PS_4KB;
660 	}
661 }
662 
663 static vm_offset_t
664 mmu_booke_alloc_kernel_pgtables(vm_offset_t data_end)
665 {
666 	/* Allocate space for ptbl_bufs. */
667 	ptbl_bufs = (struct ptbl_buf *)data_end;
668 	data_end += sizeof(struct ptbl_buf) * PTBL_BUFS;
669 	debugf(" ptbl_bufs at 0x%"PRI0ptrX" end = 0x%"PRI0ptrX"\n",
670 	    (uintptr_t)ptbl_bufs, data_end);
671 
672 	data_end = round_page(data_end);
673 
674 	kernel_ptbl_root = data_end;
675 	data_end += PDIR_NENTRIES * sizeof(pte_t*);
676 
677 	/* Allocate PTE tables for kernel KVA. */
678 	kernel_ptbls = howmany(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS,
679 	    PDIR_SIZE);
680 	data_end += kernel_ptbls * PTBL_PAGES * PAGE_SIZE;
681 	debugf(" kernel ptbls: %d\n", kernel_ptbls);
682 	debugf(" kernel pdir at %#jx end = %#jx\n",
683 	    (uintmax_t)kernel_ptbl_root, (uintmax_t)data_end);
684 
685 	return (data_end);
686 }
687 
688 /*
689  * Initialize a preallocated and zeroed pmap structure,
690  * such as one in a vmspace structure.
691  */
692 static int
693 mmu_booke_pinit(pmap_t pmap)
694 {
695 	int i;
696 
697 	CTR4(KTR_PMAP, "%s: pmap = %p, proc %d '%s'", __func__, pmap,
698 	    curthread->td_proc->p_pid, curthread->td_proc->p_comm);
699 
700 	KASSERT((pmap != kernel_pmap), ("pmap_pinit: initializing kernel_pmap"));
701 
702 	for (i = 0; i < MAXCPU; i++)
703 		pmap->pm_tid[i] = TID_NONE;
704 	CPU_ZERO(&kernel_pmap->pm_active);
705 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
706 	pmap->pm_pdir = uma_zalloc(ptbl_root_zone, M_WAITOK);
707 	bzero(pmap->pm_pdir, sizeof(pte_t *) * PDIR_NENTRIES);
708 	TAILQ_INIT(&pmap->pm_ptbl_list);
709 
710 	return (1);
711 }
712 
713 /*
714  * Release any resources held by the given physical map.
715  * Called when a pmap initialized by mmu_booke_pinit is being released.
716  * Should only be called if the map contains no valid mappings.
717  */
718 static void
719 mmu_booke_release(pmap_t pmap)
720 {
721 
722 	KASSERT(pmap->pm_stats.resident_count == 0,
723 	    ("pmap_release: pmap resident count %ld != 0",
724 	    pmap->pm_stats.resident_count));
725 	uma_zfree(ptbl_root_zone, pmap->pm_pdir);
726 }
727 
728 static void
729 mmu_booke_sync_icache(pmap_t pm, vm_offset_t va, vm_size_t sz)
730 {
731 	pte_t *pte;
732 	vm_paddr_t pa = 0;
733 	int sync_sz, valid;
734 	pmap_t pmap;
735 	vm_page_t m;
736 	vm_offset_t addr;
737 	int active;
738 
739 	rw_wlock(&pvh_global_lock);
740 	pmap = PCPU_GET(curpmap);
741 	active = (pm == kernel_pmap || pm == pmap) ? 1 : 0;
742 	while (sz > 0) {
743 		PMAP_LOCK(pm);
744 		pte = pte_find(pm, va);
745 		valid = (pte != NULL && PTE_ISVALID(pte)) ? 1 : 0;
746 		if (valid)
747 			pa = PTE_PA(pte);
748 		PMAP_UNLOCK(pm);
749 		sync_sz = PAGE_SIZE - (va & PAGE_MASK);
750 		sync_sz = min(sync_sz, sz);
751 		if (valid) {
752 			if (!active) {
753 				/* Create a mapping in the active pmap. */
754 				addr = 0;
755 				m = PHYS_TO_VM_PAGE(pa);
756 				PMAP_LOCK(pmap);
757 				pte_enter(pmap, m, addr,
758 				    PTE_SR | PTE_VALID, FALSE);
759 				addr += (va & PAGE_MASK);
760 				__syncicache((void *)addr, sync_sz);
761 				pte_remove(pmap, addr, PTBL_UNHOLD);
762 				PMAP_UNLOCK(pmap);
763 			} else
764 				__syncicache((void *)va, sync_sz);
765 		}
766 		va += sync_sz;
767 		sz -= sync_sz;
768 	}
769 	rw_wunlock(&pvh_global_lock);
770 }
771 
772 /*
773  * mmu_booke_zero_page_area zeros the specified hardware page by
774  * mapping it into virtual memory and using bzero to clear
775  * its contents.
776  *
777  * off and size must reside within a single page.
778  */
779 static void
780 mmu_booke_zero_page_area(vm_page_t m, int off, int size)
781 {
782 	vm_offset_t va;
783 
784 	/* XXX KASSERT off and size are within a single page? */
785 
786 	mtx_lock(&zero_page_mutex);
787 	va = zero_page_va;
788 
789 	mmu_booke_kenter(va, VM_PAGE_TO_PHYS(m));
790 	bzero((caddr_t)va + off, size);
791 	mmu_booke_kremove(va);
792 
793 	mtx_unlock(&zero_page_mutex);
794 }
795 
796 /*
797  * mmu_booke_zero_page zeros the specified hardware page.
798  */
799 static void
800 mmu_booke_zero_page(vm_page_t m)
801 {
802 	vm_offset_t off, va;
803 
804 	va = zero_page_va;
805 	mtx_lock(&zero_page_mutex);
806 
807 	mmu_booke_kenter(va, VM_PAGE_TO_PHYS(m));
808 
809 	for (off = 0; off < PAGE_SIZE; off += cacheline_size)
810 		__asm __volatile("dcbz 0,%0" :: "r"(va + off));
811 
812 	mmu_booke_kremove(va);
813 
814 	mtx_unlock(&zero_page_mutex);
815 }
816 
817 /*
818  * mmu_booke_copy_page copies the specified (machine independent) page by
819  * mapping the page into virtual memory and using memcopy to copy the page,
820  * one machine dependent page at a time.
821  */
822 static void
823 mmu_booke_copy_page(vm_page_t sm, vm_page_t dm)
824 {
825 	vm_offset_t sva, dva;
826 
827 	sva = copy_page_src_va;
828 	dva = copy_page_dst_va;
829 
830 	mtx_lock(&copy_page_mutex);
831 	mmu_booke_kenter(sva, VM_PAGE_TO_PHYS(sm));
832 	mmu_booke_kenter(dva, VM_PAGE_TO_PHYS(dm));
833 
834 	memcpy((caddr_t)dva, (caddr_t)sva, PAGE_SIZE);
835 
836 	mmu_booke_kremove(dva);
837 	mmu_booke_kremove(sva);
838 	mtx_unlock(&copy_page_mutex);
839 }
840 
841 static inline void
842 mmu_booke_copy_pages(vm_page_t *ma, vm_offset_t a_offset,
843     vm_page_t *mb, vm_offset_t b_offset, int xfersize)
844 {
845 	void *a_cp, *b_cp;
846 	vm_offset_t a_pg_offset, b_pg_offset;
847 	int cnt;
848 
849 	mtx_lock(&copy_page_mutex);
850 	while (xfersize > 0) {
851 		a_pg_offset = a_offset & PAGE_MASK;
852 		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
853 		mmu_booke_kenter(copy_page_src_va,
854 		    VM_PAGE_TO_PHYS(ma[a_offset >> PAGE_SHIFT]));
855 		a_cp = (char *)copy_page_src_va + a_pg_offset;
856 		b_pg_offset = b_offset & PAGE_MASK;
857 		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
858 		mmu_booke_kenter(copy_page_dst_va,
859 		    VM_PAGE_TO_PHYS(mb[b_offset >> PAGE_SHIFT]));
860 		b_cp = (char *)copy_page_dst_va + b_pg_offset;
861 		bcopy(a_cp, b_cp, cnt);
862 		mmu_booke_kremove(copy_page_dst_va);
863 		mmu_booke_kremove(copy_page_src_va);
864 		a_offset += cnt;
865 		b_offset += cnt;
866 		xfersize -= cnt;
867 	}
868 	mtx_unlock(&copy_page_mutex);
869 }
870 
871 static vm_offset_t
872 mmu_booke_quick_enter_page(vm_page_t m)
873 {
874 	vm_paddr_t paddr;
875 	vm_offset_t qaddr;
876 	uint32_t flags;
877 	pte_t *pte;
878 
879 	paddr = VM_PAGE_TO_PHYS(m);
880 
881 	flags = PTE_SR | PTE_SW | PTE_SX | PTE_WIRED | PTE_VALID;
882 	flags |= tlb_calc_wimg(paddr, pmap_page_get_memattr(m)) << PTE_MAS2_SHIFT;
883 	flags |= PTE_PS_4KB;
884 
885 	critical_enter();
886 	qaddr = PCPU_GET(qmap_addr);
887 
888 	pte = pte_find(kernel_pmap, qaddr);
889 
890 	KASSERT(*pte == 0, ("mmu_booke_quick_enter_page: PTE busy"));
891 
892 	/*
893 	 * XXX: tlbivax is broadcast to other cores, but qaddr should
894  	 * not be present in other TLBs.  Is there a better instruction
895 	 * sequence to use? Or just forget it & use mmu_booke_kenter()...
896 	 */
897 	__asm __volatile("tlbivax 0, %0" :: "r"(qaddr & MAS2_EPN_MASK));
898 	__asm __volatile("isync; msync");
899 
900 	*pte = PTE_RPN_FROM_PA(paddr) | flags;
901 
902 	/* Flush the real memory from the instruction cache. */
903 	if ((flags & (PTE_I | PTE_G)) == 0)
904 		__syncicache((void *)qaddr, PAGE_SIZE);
905 
906 	return (qaddr);
907 }
908 
909 static void
910 mmu_booke_quick_remove_page(vm_offset_t addr)
911 {
912 	pte_t *pte;
913 
914 	pte = pte_find(kernel_pmap, addr);
915 
916 	KASSERT(PCPU_GET(qmap_addr) == addr,
917 	    ("mmu_booke_quick_remove_page: invalid address"));
918 	KASSERT(*pte != 0,
919 	    ("mmu_booke_quick_remove_page: PTE not in use"));
920 
921 	*pte = 0;
922 	critical_exit();
923 }
924 
925 /**************************************************************************/
926 /* TID handling */
927 /**************************************************************************/
928 
929 /*
930  * Return the largest uint value log such that 2^log <= num.
931  */
932 static unsigned long
933 ilog2(unsigned long num)
934 {
935 	long lz;
936 
937 	__asm ("cntlzw %0, %1" : "=r" (lz) : "r" (num));
938 	return (31 - lz);
939 }
940 
941 /*
942  * Invalidate all TLB0 entries which match the given TID. Note this is
943  * dedicated for cases when invalidations should NOT be propagated to other
944  * CPUs.
945  */
946 static void
947 tid_flush(tlbtid_t tid)
948 {
949 	register_t msr;
950 	uint32_t mas0, mas1, mas2;
951 	int entry, way;
952 
953 
954 	/* Don't evict kernel translations */
955 	if (tid == TID_KERNEL)
956 		return;
957 
958 	msr = mfmsr();
959 	__asm __volatile("wrteei 0");
960 
961 	/*
962 	 * Newer (e500mc and later) have tlbilx, which doesn't broadcast, so use
963 	 * it for PID invalidation.
964 	 */
965 	switch ((mfpvr() >> 16) & 0xffff) {
966 	case FSL_E500mc:
967 	case FSL_E5500:
968 	case FSL_E6500:
969 		mtspr(SPR_MAS6, tid << MAS6_SPID0_SHIFT);
970 		/* tlbilxpid */
971 		__asm __volatile("isync; .long 0x7c200024; isync; msync");
972 		__asm __volatile("wrtee %0" :: "r"(msr));
973 		return;
974 	}
975 
976 	for (way = 0; way < TLB0_WAYS; way++)
977 		for (entry = 0; entry < TLB0_ENTRIES_PER_WAY; entry++) {
978 
979 			mas0 = MAS0_TLBSEL(0) | MAS0_ESEL(way);
980 			mtspr(SPR_MAS0, mas0);
981 
982 			mas2 = entry << MAS2_TLB0_ENTRY_IDX_SHIFT;
983 			mtspr(SPR_MAS2, mas2);
984 
985 			__asm __volatile("isync; tlbre");
986 
987 			mas1 = mfspr(SPR_MAS1);
988 
989 			if (!(mas1 & MAS1_VALID))
990 				continue;
991 			if (((mas1 & MAS1_TID_MASK) >> MAS1_TID_SHIFT) != tid)
992 				continue;
993 			mas1 &= ~MAS1_VALID;
994 			mtspr(SPR_MAS1, mas1);
995 			__asm __volatile("isync; tlbwe; isync; msync");
996 		}
997 	__asm __volatile("wrtee %0" :: "r"(msr));
998 }
999