vfs: check userland buffers before reading them.
[haiku.git] / src / system / kernel / arch / x86 / arch_vm_translation_map.cpp
blob728dbd811bf1361aa547a6e04e41a66bc43bef5f
1 /*
2 * Copyright 2008-2010, Ingo Weinhold, ingo_weinhold@gmx.de.
3 * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
4 * Distributed under the terms of the MIT License.
6 * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
7 * Distributed under the terms of the NewOS License.
8 */
11 #include <arch/vm_translation_map.h>
13 #include <boot/kernel_args.h>
14 #include <safemode.h>
16 #ifdef __x86_64__
17 # include "paging/64bit/X86PagingMethod64Bit.h"
18 #else
19 # include "paging/32bit/X86PagingMethod32Bit.h"
20 # include "paging/pae/X86PagingMethodPAE.h"
21 #endif
24 //#define TRACE_VM_TMAP
25 #ifdef TRACE_VM_TMAP
26 # define TRACE(x...) dprintf(x)
27 #else
28 # define TRACE(x...) ;
29 #endif
32 static union {
33 uint64 align;
34 #ifdef __x86_64__
35 char sixty_four[sizeof(X86PagingMethod64Bit)];
36 #else
37 char thirty_two[sizeof(X86PagingMethod32Bit)];
38 #if B_HAIKU_PHYSICAL_BITS == 64
39 char pae[sizeof(X86PagingMethodPAE)];
40 #endif
41 #endif
42 } sPagingMethodBuffer;
45 // #pragma mark - VM API
48 status_t
49 arch_vm_translation_map_create_map(bool kernel, VMTranslationMap** _map)
51 return gX86PagingMethod->CreateTranslationMap(kernel, _map);
55 status_t
56 arch_vm_translation_map_init(kernel_args *args,
57 VMPhysicalPageMapper** _physicalPageMapper)
59 TRACE("vm_translation_map_init: entry\n");
61 #ifdef TRACE_VM_TMAP
62 TRACE("physical memory ranges:\n");
63 for (uint32 i = 0; i < args->num_physical_memory_ranges; i++) {
64 phys_addr_t start = args->physical_memory_range[i].start;
65 phys_addr_t end = start + args->physical_memory_range[i].size;
66 TRACE(" %#10" B_PRIxPHYSADDR " - %#10" B_PRIxPHYSADDR "\n", start,
67 end);
70 TRACE("allocated physical ranges:\n");
71 for (uint32 i = 0; i < args->num_physical_allocated_ranges; i++) {
72 phys_addr_t start = args->physical_allocated_range[i].start;
73 phys_addr_t end = start + args->physical_allocated_range[i].size;
74 TRACE(" %#10" B_PRIxPHYSADDR " - %#10" B_PRIxPHYSADDR "\n", start,
75 end);
78 TRACE("allocated virtual ranges:\n");
79 for (uint32 i = 0; i < args->num_virtual_allocated_ranges; i++) {
80 addr_t start = args->virtual_allocated_range[i].start;
81 addr_t end = start + args->virtual_allocated_range[i].size;
82 TRACE(" %#10" B_PRIxADDR " - %#10" B_PRIxADDR "\n", start, end);
84 #endif
86 #ifdef __x86_64__
87 gX86PagingMethod = new(&sPagingMethodBuffer) X86PagingMethod64Bit;
88 #elif B_HAIKU_PHYSICAL_BITS == 64
89 bool paeAvailable = x86_check_feature(IA32_FEATURE_PAE, FEATURE_COMMON);
90 bool paeNeeded = x86_check_feature(IA32_FEATURE_AMD_EXT_NX,
91 FEATURE_EXT_AMD);
92 if (!paeNeeded) {
93 for (uint32 i = 0; i < args->num_physical_memory_ranges; i++) {
94 phys_addr_t end = args->physical_memory_range[i].start
95 + args->physical_memory_range[i].size;
96 if (end > 0x100000000LL) {
97 paeNeeded = true;
98 break;
103 bool paeDisabled = get_safemode_boolean_early(args,
104 B_SAFEMODE_4_GB_MEMORY_LIMIT, false);
106 if (paeAvailable && paeNeeded && !paeDisabled) {
107 dprintf("using PAE paging\n");
108 gX86PagingMethod = new(&sPagingMethodBuffer) X86PagingMethodPAE;
109 } else {
110 dprintf("using 32 bit paging (PAE %s)\n",
111 paeNeeded
112 ? "not available"
113 : (paeDisabled ? "disabled" : "not needed"));
114 gX86PagingMethod = new(&sPagingMethodBuffer) X86PagingMethod32Bit;
116 #else
117 gX86PagingMethod = new(&sPagingMethodBuffer) X86PagingMethod32Bit;
118 #endif
120 return gX86PagingMethod->Init(args, _physicalPageMapper);
124 status_t
125 arch_vm_translation_map_init_post_sem(kernel_args *args)
127 return B_OK;
131 status_t
132 arch_vm_translation_map_init_post_area(kernel_args *args)
134 TRACE("vm_translation_map_init_post_area: entry\n");
136 return gX86PagingMethod->InitPostArea(args);
140 status_t
141 arch_vm_translation_map_early_map(kernel_args *args, addr_t va, phys_addr_t pa,
142 uint8 attributes, phys_addr_t (*get_free_page)(kernel_args *))
144 TRACE("early_tmap: entry pa %#" B_PRIxPHYSADDR " va %#" B_PRIxADDR "\n", pa,
145 va);
147 return gX86PagingMethod->MapEarly(args, va, pa, attributes, get_free_page);
151 /*! Verifies that the page at the given virtual address can be accessed in the
152 current context.
154 This function is invoked in the kernel debugger. Paranoid checking is in
155 order.
157 \param virtualAddress The virtual address to be checked.
158 \param protection The area protection for which to check. Valid is a bitwise
159 or of one or more of \c B_KERNEL_READ_AREA or \c B_KERNEL_WRITE_AREA.
160 \return \c true, if the address can be accessed in all ways specified by
161 \a protection, \c false otherwise.
163 bool
164 arch_vm_translation_map_is_kernel_page_accessible(addr_t virtualAddress,
165 uint32 protection)
167 if (!gX86PagingMethod)
168 return true;
170 return gX86PagingMethod->IsKernelPageAccessible(virtualAddress, protection);