1/* $NetBSD: pmap.h,v 1.99 2022/07/19 22:04:14 riastradh Exp $ */
2
3/*-
4 * Copyright (c) 1998, 1999, 2000, 2001, 2007 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center and by Chris G. Demetriou.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33/*
34 * Copyright (c) 1991, 1993
35 *	The Regents of the University of California.  All rights reserved.
36 *
37 * This code is derived from software contributed to Berkeley by
38 * the Systems Programming Group of the University of Utah Computer
39 * Science Department.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 *    notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 *    notice, this list of conditions and the following disclaimer in the
48 *    documentation and/or other materials provided with the distribution.
49 * 3. Neither the name of the University nor the names of its contributors
50 *    may be used to endorse or promote products derived from this software
51 *    without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 *	@(#)pmap.h	8.1 (Berkeley) 6/10/93
66 */
67
68/*
69 * Copyright (c) 1987 Carnegie-Mellon University
70 *
71 * This code is derived from software contributed to Berkeley by
72 * the Systems Programming Group of the University of Utah Computer
73 * Science Department.
74 *
75 * Redistribution and use in source and binary forms, with or without
76 * modification, are permitted provided that the following conditions
77 * are met:
78 * 1. Redistributions of source code must retain the above copyright
79 *    notice, this list of conditions and the following disclaimer.
80 * 2. Redistributions in binary form must reproduce the above copyright
81 *    notice, this list of conditions and the following disclaimer in the
82 *    documentation and/or other materials provided with the distribution.
83 * 3. All advertising materials mentioning features or use of this software
84 *    must display the following acknowledgement:
85 *	This product includes software developed by the University of
86 *	California, Berkeley and its contributors.
87 * 4. Neither the name of the University nor the names of its contributors
88 *    may be used to endorse or promote products derived from this software
89 *    without specific prior written permission.
90 *
91 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
92 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
94 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
95 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
96 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
97 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
98 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
99 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
100 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
101 * SUCH DAMAGE.
102 *
103 *	@(#)pmap.h	8.1 (Berkeley) 6/10/93
104 */
105
106#ifndef	_PMAP_MACHINE_
107#define	_PMAP_MACHINE_
108
109#if defined(_KERNEL_OPT)
110#include "opt_multiprocessor.h"
111#endif
112
113#include <sys/param.h>
114#include <sys/types.h>
115
116#include <sys/mutex.h>
117#include <sys/queue.h>
118
119#include <machine/pte.h>
120
121/*
122 * Machine-dependent virtual memory state.
123 *
124 * If we ever support processor numbers higher than 63, we'll have to
125 * rethink the CPU mask.
126 *
127 * Note pm_asn and pm_asngen are arrays allocated in pmap_create().
128 * Their size is based on the PCS count from the HWRPB, and indexed
129 * by processor ID (from `whami').  This is all padded to COHERENCY_UNIT
130 * to avoid false sharing.
131 *
132 * The kernel pmap is a special case; since the kernel uses only ASM
133 * mappings and uses a reserved ASN to keep the TLB clean, we don't
134 * allocate any ASN info for the kernel pmap at all.
135 * arrays which hold enough for ALPHA_MAXPROCS.
136 */
137
138LIST_HEAD(pmap_pagelist, vm_page);
139LIST_HEAD(pmap_pvlist, pv_entry);
140
141struct pmap_percpu {
142	unsigned int		pmc_asn;	/* address space number */
143	unsigned int		pmc_pad0;
144	unsigned long		pmc_asngen;	/* ASN generation number */
145	unsigned int		pmc_needisync;	/* CPU needes isync */
146	unsigned int		pmc_pad1;
147	pt_entry_t		*pmc_lev1map;	/* level 1 map */
148	unsigned long		pmc_padN[(COHERENCY_UNIT / 8) - 4];
149};
150
151struct pmap {	/* pmaps are aligned to COHERENCY_UNIT boundaries */
152		/* pmaps are locked by hashed mutexes */
153	unsigned long		pm_cpus;	/* [ 0] CPUs using pmap */
154	struct pmap_statistics	pm_stats;	/* [ 8] statistics */
155	unsigned int		pm_count;	/* [24] reference count */
156	unsigned int		__pm_spare0;	/* [28] spare field */
157	struct pmap_pagelist	pm_ptpages;	/* [32] list of PT pages */
158	struct pmap_pvlist	pm_pvents;	/* [40] list of PV entries */
159	TAILQ_ENTRY(pmap)	pm_list;	/* [48] list of all pmaps */
160	/* -- COHERENCY_UNIT boundary -- */
161	struct pmap_percpu	pm_percpu[];	/* [64] per-CPU data */
162			/*	variable length		*/
163};
164
165#define	PMAP_SIZEOF(x)							\
166	(ALIGN(offsetof(struct pmap, pm_percpu[(x)])))
167
168#define	PMAP_ASN_KERNEL		0	/* kernel-reserved ASN */
169#define	PMAP_ASN_FIRST_USER	1	/* first user ASN */
170#define	PMAP_ASNGEN_INVALID	0	/* reserved (invalid) ASN generation */
171#define	PMAP_ASNGEN_INITIAL	1	/* first valid generatation */
172
173/*
174 * For each struct vm_page, there is a list of all currently valid virtual
175 * mappings of that page.  An entry is a pv_entry_t, the list is pv_table.
176 */
177typedef struct pv_entry {
178	struct pv_entry	*pv_next;	/* next pv_entry on page list */
179	LIST_ENTRY(pv_entry) pv_link;	/* link on owning pmap's list */
180	struct pmap	*pv_pmap;	/* pmap where mapping lies */
181	vaddr_t		pv_va;		/* virtual address for mapping */
182	pt_entry_t	*pv_pte;	/* PTE that maps the VA */
183} *pv_entry_t;
184
185/* attrs in pvh_listx */
186#define	PGA_MODIFIED		0x01UL		/* modified */
187#define	PGA_REFERENCED		0x02UL		/* referenced */
188#define	PGA_ATTRS		(PGA_MODIFIED | PGA_REFERENCED)
189
190/* pvh_usage */
191#define	PGU_NORMAL		0		/* free or normal use */
192#define	PGU_PVENT		1		/* PV entries */
193#define	PGU_L1PT		2		/* level 1 page table */
194#define	PGU_L2PT		3		/* level 2 page table */
195#define	PGU_L3PT		4		/* level 3 page table */
196
197#ifdef _KERNEL
198
199#include <sys/atomic.h>
200
201struct cpu_info;
202struct trapframe;
203
204void	pmap_init_cpu(struct cpu_info *);
205#if defined(MULTIPROCESSOR)
206void	pmap_tlb_shootdown_ipi(struct cpu_info *, struct trapframe *);
207#endif /* MULTIPROCESSOR */
208
209#define	pmap_resident_count(pmap)	((pmap)->pm_stats.resident_count)
210#define	pmap_wired_count(pmap)		((pmap)->pm_stats.wired_count)
211
212#define	pmap_copy(dp, sp, da, l, sa)	/* nothing */
213#define	pmap_update(pmap)		/* nothing (yet) */
214
215#define	pmap_is_referenced(pg)						\
216	(((pg)->mdpage.pvh_listx & PGA_REFERENCED) != 0)
217#define	pmap_is_modified(pg)						\
218	(((pg)->mdpage.pvh_listx & PGA_MODIFIED) != 0)
219
220#define	PMAP_STEAL_MEMORY		/* enable pmap_steal_memory() */
221#define	PMAP_GROWKERNEL			/* enable pmap_growkernel() */
222
223#define	PMAP_DIRECT
224#define	PMAP_DIRECT_MAP(pa)		ALPHA_PHYS_TO_K0SEG((pa))
225#define	PMAP_DIRECT_UNMAP(va)		ALPHA_K0SEG_TO_PHYS((va))
226
227static __inline int
228pmap_direct_process(paddr_t pa, voff_t pgoff, size_t len,
229    int (*process)(void *, size_t, void *), void *arg)
230{
231	vaddr_t va = PMAP_DIRECT_MAP(pa);
232
233	return process((void *)(va + pgoff), len, arg);
234}
235
236/*
237 * Alternate mapping hooks for pool pages.  Avoids thrashing the TLB.
238 */
239#define	PMAP_MAP_POOLPAGE(pa)		PMAP_DIRECT_MAP(pa)
240#define	PMAP_UNMAP_POOLPAGE(va)		PMAP_DIRECT_UNMAP(va)
241
242/*
243 * Other hooks for the pool allocator.
244 */
245#define	POOL_VTOPHYS(va)		ALPHA_K0SEG_TO_PHYS((vaddr_t) (va))
246
247bool	pmap_pageidlezero(paddr_t);
248#define	PMAP_PAGEIDLEZERO(pa)	pmap_pageidlezero((pa))
249
250paddr_t vtophys(vaddr_t);
251
252/* Machine-specific functions. */
253void	pmap_bootstrap(paddr_t, u_int, u_long);
254int	pmap_emulate_reference(struct lwp *, vaddr_t, int, int);
255
256#define	pmap_pte_pa(pte)	(PG_PFNUM(*(pte)) << PGSHIFT)
257#define	pmap_pte_prot(pte)	(*(pte) & PG_PROT)
258#define	pmap_pte_w(pte)		(*(pte) & PG_WIRED)
259#define	pmap_pte_v(pte)		(*(pte) & PG_V)
260#define	pmap_pte_pv(pte)	(*(pte) & PG_PVLIST)
261#define	pmap_pte_asm(pte)	(*(pte) & PG_ASM)
262#define	pmap_pte_exec(pte)	(*(pte) & PG_EXEC)
263
264#define	pmap_pte_set_w(pte, v)						\
265do {									\
266	if (v)								\
267		*(pte) |= PG_WIRED;					\
268	else								\
269		*(pte) &= ~PG_WIRED;					\
270} while (0)
271
272#define	pmap_pte_w_chg(pte, nw)	((nw) ^ pmap_pte_w(pte))
273
274#define	pmap_pte_set_prot(pte, np)					\
275do {									\
276	*(pte) &= ~PG_PROT;						\
277	*(pte) |= (np);							\
278} while (0)
279
280#define	pmap_pte_prot_chg(pte, np) ((np) ^ pmap_pte_prot(pte))
281
282static __inline pt_entry_t *
283pmap_lev1map(pmap_t pmap)
284{
285	if (__predict_false(pmap == pmap_kernel())) {
286		return kernel_lev1map;
287	}
288	/*
289	 * We're just reading a per-CPU field that's the same on
290	 * all CPUs, so don't bother disabling preemption around
291	 * this.
292	 */
293	return pmap->pm_percpu[cpu_number()].pmc_lev1map;
294}
295
296static __inline pt_entry_t *
297pmap_l1pte(pt_entry_t *lev1map, vaddr_t v)
298{
299	KASSERT(lev1map != NULL);
300	return &lev1map[l1pte_index(v)];
301}
302
303static __inline pt_entry_t *
304pmap_l2pte(pt_entry_t *lev1map, vaddr_t v, pt_entry_t *l1pte)
305{
306	pt_entry_t *lev2map;
307
308	if (l1pte == NULL) {
309		l1pte = pmap_l1pte(lev1map, v);
310		if (pmap_pte_v(l1pte) == 0)
311			return NULL;
312	}
313
314	lev2map = (pt_entry_t *)ALPHA_PHYS_TO_K0SEG(pmap_pte_pa(l1pte));
315	return &lev2map[l2pte_index(v)];
316}
317
318static __inline pt_entry_t *
319pmap_l3pte(pt_entry_t *lev1map, vaddr_t v, pt_entry_t *l2pte)
320{
321	pt_entry_t *l1pte, *lev2map, *lev3map;
322
323	if (l2pte == NULL) {
324		l1pte = pmap_l1pte(lev1map, v);
325		if (pmap_pte_v(l1pte) == 0)
326			return NULL;
327
328		lev2map = (pt_entry_t *)ALPHA_PHYS_TO_K0SEG(pmap_pte_pa(l1pte));
329		l2pte = &lev2map[l2pte_index(v)];
330		if (pmap_pte_v(l2pte) == 0)
331			return NULL;
332	}
333
334	lev3map = (pt_entry_t *)ALPHA_PHYS_TO_K0SEG(pmap_pte_pa(l2pte));
335	return &lev3map[l3pte_index(v)];
336}
337
338/*
339 * Macro for processing deferred I-stream synchronization.
340 *
341 * The pmap module may defer syncing the user I-stream until the
342 * return to userspace, since the IMB PALcode op can be quite
343 * expensive.  Since user instructions won't be executed until
344 * the return to userspace, this can be deferred until userret().
345 */
346#define	PMAP_USERRET(pmap)						\
347do {									\
348	const unsigned long cpu_id = cpu_number();			\
349									\
350	if ((pmap)->pm_percpu[cpu_id].pmc_needisync) {			\
351		(pmap)->pm_percpu[cpu_id].pmc_needisync = 0;		\
352		alpha_pal_imb();					\
353	}								\
354} while (0)
355
356/*
357 * pmap-specific data store in the vm_page structure.
358 */
359#define	__HAVE_VM_PAGE_MD
360struct vm_page_md {
361	uintptr_t pvh_listx;		/* pv_entry list + attrs */
362	/*
363	 * XXX These fields are only needed for pages that are used
364	 * as PT pages.  It would be nice to find safely-unused fields
365	 * in the vm_page structure that could be used instead.
366	 *
367	 * (Only 11 bits are needed ... we need to be able to count from
368	 * 0-1025 ... 1025 because sometimes we need to take an extra
369	 * reference temporarily in pmap_enter().)
370	 */
371	unsigned int pvh_physpgrefs;	/* # refs as a PT page */
372	unsigned int pvh_spare0;	/* XXX spare field */
373};
374
375/* Reference counting for page table pages. */
376#define	PHYSPAGE_REFCNT(pg)						\
377	atomic_load_relaxed(&(pg)->mdpage.pvh_physpgrefs)
378#define	PHYSPAGE_REFCNT_SET(pg, v)					\
379	atomic_store_relaxed(&(pg)->mdpage.pvh_physpgrefs, (v))
380#define	PHYSPAGE_REFCNT_INC(pg)						\
381	atomic_inc_uint_nv(&(pg)->mdpage.pvh_physpgrefs)
382#define	PHYSPAGE_REFCNT_DEC(pg)						\
383	atomic_dec_uint_nv(&(pg)->mdpage.pvh_physpgrefs)
384
385#define	VM_MDPAGE_PVS(pg)						\
386	((struct pv_entry *)((pg)->mdpage.pvh_listx & ~3UL))
387
388#define	VM_MDPAGE_INIT(pg)						\
389do {									\
390	(pg)->mdpage.pvh_listx = 0UL;					\
391} while (/*CONSTCOND*/0)
392
393#endif /* _KERNEL */
394
395#endif /* _PMAP_MACHINE_ */
396