1/*
2 * fixmap.h: compile-time virtual memory allocation
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License.  See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 1998 Ingo Molnar
9 *
10 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
11 * x86_32 and x86_64 integration by Gustavo F. Padovan, February 2009
12 */
13
14#ifndef _ASM_X86_FIXMAP_H
15#define _ASM_X86_FIXMAP_H
16
17/*
18 * Exposed to assembly code for setting up initial page tables. Cannot be
19 * calculated in assembly code (fixmap entries are an enum), but is sanity
20 * checked in the actual fixmap C code to make sure that the fixmap is
21 * covered fully.
22 */
23#define FIXMAP_PMD_NUM	2
24/* fixmap starts downwards from the 507th entry in level2_fixmap_pgt */
25#define FIXMAP_PMD_TOP	507
26
27#ifndef __ASSEMBLY__
28#include <linux/kernel.h>
29#include <asm/apicdef.h>
30#include <asm/page.h>
31#include <asm/pgtable_types.h>
32#ifdef CONFIG_X86_32
33#include <linux/threads.h>
34#include <asm/kmap_types.h>
35#else
36#include <uapi/asm/vsyscall.h>
37#endif
38
39/*
40 * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
41 * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
42 * Because of this, FIXADDR_TOP x86 integration was left as later work.
43 */
44#ifdef CONFIG_X86_32
45/*
46 * Leave one empty page between vmalloc'ed areas and
47 * the start of the fixmap.
48 */
49extern unsigned long __FIXADDR_TOP;
50#define FIXADDR_TOP	((unsigned long)__FIXADDR_TOP)
51#else
52#define FIXADDR_TOP	(round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
53			 PAGE_SIZE)
54#endif
55
56/*
57 * Here we define all the compile-time 'special' virtual
58 * addresses. The point is to have a constant address at
59 * compile time, but to set the physical address only
60 * in the boot process.
61 * for x86_32: We allocate these special addresses
62 * from the end of virtual memory (0xfffff000) backwards.
63 * Also this lets us do fail-safe vmalloc(), we
64 * can guarantee that these special addresses and
65 * vmalloc()-ed addresses never overlap.
66 *
67 * These 'compile-time allocated' memory buffers are
68 * fixed-size 4k pages (or larger if used with an increment
69 * higher than 1). Use set_fixmap(idx,phys) to associate
70 * physical memory with fixmap indices.
71 *
72 * TLB entries of such buffers will not be flushed across
73 * task switches.
74 */
75enum fixed_addresses {
76#ifdef CONFIG_X86_32
77	FIX_HOLE,
78#else
79#ifdef CONFIG_X86_VSYSCALL_EMULATION
80	VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
81#endif
82#endif
83	FIX_DBGP_BASE,
84	FIX_EARLYCON_MEM_BASE,
85#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
86	FIX_OHCI1394_BASE,
87#endif
88#ifdef CONFIG_X86_LOCAL_APIC
89	FIX_APIC_BASE,	/* local (CPU) APIC) -- required for SMP or not */
90#endif
91#ifdef CONFIG_X86_IO_APIC
92	FIX_IO_APIC_BASE_0,
93	FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
94#endif
95#ifdef CONFIG_X86_32
96	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */
97	FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
98#ifdef CONFIG_PCI_MMCONFIG
99	FIX_PCIE_MCFG,
100#endif
101#endif
102#ifdef CONFIG_PARAVIRT_XXL
103	FIX_PARAVIRT_BOOTMAP,
104#endif
105#ifdef	CONFIG_X86_INTEL_MID
106	FIX_LNW_VRTC,
107#endif
108
109#ifdef CONFIG_ACPI_APEI_GHES
110	/* Used for GHES mapping from assorted contexts */
111	FIX_APEI_GHES_IRQ,
112	FIX_APEI_GHES_NMI,
113#endif
114
115	__end_of_permanent_fixed_addresses,
116
117	/*
118	 * 512 temporary boot-time mappings, used by early_ioremap(),
119	 * before ioremap() is functional.
120	 *
121	 * If necessary we round it up to the next 512 pages boundary so
122	 * that we can have a single pmd entry and a single pte table:
123	 */
124#define NR_FIX_BTMAPS		64
125#define FIX_BTMAPS_SLOTS	8
126#define TOTAL_FIX_BTMAPS	(NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
127	FIX_BTMAP_END =
128	 (__end_of_permanent_fixed_addresses ^
129	  (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
130	 -PTRS_PER_PTE
131	 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
132	   (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
133	 : __end_of_permanent_fixed_addresses,
134	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
135#ifdef CONFIG_X86_32
136	FIX_WP_TEST,
137#endif
138#ifdef CONFIG_INTEL_TXT
139	FIX_TBOOT_BASE,
140#endif
141	__end_of_fixed_addresses
142};
143
144
145extern void reserve_top_address(unsigned long reserve);
146
147#define FIXADDR_SIZE		(__end_of_permanent_fixed_addresses << PAGE_SHIFT)
148#define FIXADDR_START		(FIXADDR_TOP - FIXADDR_SIZE)
149#define FIXADDR_TOT_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
150#define FIXADDR_TOT_START	(FIXADDR_TOP - FIXADDR_TOT_SIZE)
151
152extern int fixmaps_set;
153
154extern pte_t *kmap_pte;
155extern pte_t *pkmap_page_table;
156
157void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
158void native_set_fixmap(unsigned /* enum fixed_addresses */ idx,
159		       phys_addr_t phys, pgprot_t flags);
160
161#ifndef CONFIG_PARAVIRT_XXL
162static inline void __set_fixmap(enum fixed_addresses idx,
163				phys_addr_t phys, pgprot_t flags)
164{
165	native_set_fixmap(idx, phys, flags);
166}
167#endif
168
169/*
170 * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not
171 * supported for MMIO addresses, so make sure that the memory encryption
172 * mask is not part of the page attributes.
173 */
174#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE
175
176/*
177 * Early memremap routines used for in-place encryption. The mappings created
178 * by these routines are intended to be used as temporary mappings.
179 */
180void __init *early_memremap_encrypted(resource_size_t phys_addr,
181				      unsigned long size);
182void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
183					 unsigned long size);
184void __init *early_memremap_decrypted(resource_size_t phys_addr,
185				      unsigned long size);
186void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
187					 unsigned long size);
188
189#include <asm-generic/fixmap.h>
190
191#define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
192#define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
193
194void __early_set_fixmap(enum fixed_addresses idx,
195			phys_addr_t phys, pgprot_t flags);
196
197#endif /* !__ASSEMBLY__ */
198#endif /* _ASM_X86_FIXMAP_H */
199