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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-29 21:12:23 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-29 21:12:23 -0400
commita591afc01d9e48affbacb365558a31e53c85af45 (patch)
tree9bb91f4eb94ec69fc4706c4944788ec5f3586063 /arch/x86/vdso/vma.c
parent820d41cf0cd0e94a5661e093821e2e5c6b36a9d8 (diff)
parent31796ac4e8f0e88f5c10f1ad6dab8f19bebe44a4 (diff)
Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x32 support for x86-64 from Ingo Molnar: "This tree introduces the X32 binary format and execution mode for x86: 32-bit data space binaries using 64-bit instructions and 64-bit kernel syscalls. This allows applications whose working set fits into a 32 bits address space to make use of 64-bit instructions while using a 32-bit address space with shorter pointers, more compressed data structures, etc." Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c} * 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) x32: Fix alignment fail in struct compat_siginfo x32: Fix stupid ia32/x32 inversion in the siginfo format x32: Add ptrace for x32 x32: Switch to a 64-bit clock_t x32: Provide separate is_ia32_task() and is_x32_task() predicates x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls x86/x32: Fix the binutils auto-detect x32: Warn and disable rather than error if binutils too old x32: Only clear TIF_X32 flag once x32: Make sure TS_COMPAT is cleared for x32 tasks fs: Remove missed ->fds_bits from cessation use of fd_set structs internally fs: Fix close_on_exec pointer in alloc_fdtable x32: Drop non-__vdso weak symbols from the x32 VDSO x32: Fix coding style violations in the x32 VDSO code x32: Add x32 VDSO support x32: Allow x32 to be configured x32: If configured, add x32 system calls to system call tables x32: Handle process creation x32: Signal-related system calls x86: Add #ifdef CONFIG_COMPAT to <asm/sys_ia32.h> ...
Diffstat (limited to 'arch/x86/vdso/vma.c')
-rw-r--r--arch/x86/vdso/vma.c78
1 files changed, 70 insertions, 8 deletions
diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c
index 17e18279649f..00aaf047b39f 100644
--- a/arch/x86/vdso/vma.c
+++ b/arch/x86/vdso/vma.c
@@ -24,7 +24,44 @@ extern unsigned short vdso_sync_cpuid;
24extern struct page *vdso_pages[]; 24extern struct page *vdso_pages[];
25static unsigned vdso_size; 25static unsigned vdso_size;
26 26
27static void __init patch_vdso(void *vdso, size_t len) 27#ifdef CONFIG_X86_X32_ABI
28extern char vdsox32_start[], vdsox32_end[];
29extern struct page *vdsox32_pages[];
30static unsigned vdsox32_size;
31
32static void __init patch_vdsox32(void *vdso, size_t len)
33{
34 Elf32_Ehdr *hdr = vdso;
35 Elf32_Shdr *sechdrs, *alt_sec = 0;
36 char *secstrings;
37 void *alt_data;
38 int i;
39
40 BUG_ON(len < sizeof(Elf32_Ehdr));
41 BUG_ON(memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0);
42
43 sechdrs = (void *)hdr + hdr->e_shoff;
44 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
45
46 for (i = 1; i < hdr->e_shnum; i++) {
47 Elf32_Shdr *shdr = &sechdrs[i];
48 if (!strcmp(secstrings + shdr->sh_name, ".altinstructions")) {
49 alt_sec = shdr;
50 goto found;
51 }
52 }
53
54 /* If we get here, it's probably a bug. */
55 pr_warning("patch_vdsox32: .altinstructions not found\n");
56 return; /* nothing to patch */
57
58found:
59 alt_data = (void *)hdr + alt_sec->sh_offset;
60 apply_alternatives(alt_data, alt_data + alt_sec->sh_size);
61}
62#endif
63
64static void __init patch_vdso64(void *vdso, size_t len)
28{ 65{
29 Elf64_Ehdr *hdr = vdso; 66 Elf64_Ehdr *hdr = vdso;
30 Elf64_Shdr *sechdrs, *alt_sec = 0; 67 Elf64_Shdr *sechdrs, *alt_sec = 0;
@@ -47,7 +84,7 @@ static void __init patch_vdso(void *vdso, size_t len)
47 } 84 }
48 85
49 /* If we get here, it's probably a bug. */ 86 /* If we get here, it's probably a bug. */
50 pr_warning("patch_vdso: .altinstructions not found\n"); 87 pr_warning("patch_vdso64: .altinstructions not found\n");
51 return; /* nothing to patch */ 88 return; /* nothing to patch */
52 89
53found: 90found:
@@ -60,12 +97,20 @@ static int __init init_vdso(void)
60 int npages = (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE; 97 int npages = (vdso_end - vdso_start + PAGE_SIZE - 1) / PAGE_SIZE;
61 int i; 98 int i;
62 99
63 patch_vdso(vdso_start, vdso_end - vdso_start); 100 patch_vdso64(vdso_start, vdso_end - vdso_start);
64 101
65 vdso_size = npages << PAGE_SHIFT; 102 vdso_size = npages << PAGE_SHIFT;
66 for (i = 0; i < npages; i++) 103 for (i = 0; i < npages; i++)
67 vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE); 104 vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE);
68 105
106#ifdef CONFIG_X86_X32_ABI
107 patch_vdsox32(vdsox32_start, vdsox32_end - vdsox32_start);
108 npages = (vdsox32_end - vdsox32_start + PAGE_SIZE - 1) / PAGE_SIZE;
109 vdsox32_size = npages << PAGE_SHIFT;
110 for (i = 0; i < npages; i++)
111 vdsox32_pages[i] = virt_to_page(vdsox32_start + i*PAGE_SIZE);
112#endif
113
69 return 0; 114 return 0;
70} 115}
71subsys_initcall(init_vdso); 116subsys_initcall(init_vdso);
@@ -103,7 +148,10 @@ static unsigned long vdso_addr(unsigned long start, unsigned len)
103 148
104/* Setup a VMA at program startup for the vsyscall page. 149/* Setup a VMA at program startup for the vsyscall page.
105 Not called for compat tasks */ 150 Not called for compat tasks */
106int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 151static int setup_additional_pages(struct linux_binprm *bprm,
152 int uses_interp,
153 struct page **pages,
154 unsigned size)
107{ 155{
108 struct mm_struct *mm = current->mm; 156 struct mm_struct *mm = current->mm;
109 unsigned long addr; 157 unsigned long addr;
@@ -113,8 +161,8 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
113 return 0; 161 return 0;
114 162
115 down_write(&mm->mmap_sem); 163 down_write(&mm->mmap_sem);
116 addr = vdso_addr(mm->start_stack, vdso_size); 164 addr = vdso_addr(mm->start_stack, size);
117 addr = get_unmapped_area(NULL, addr, vdso_size, 0, 0); 165 addr = get_unmapped_area(NULL, addr, size, 0, 0);
118 if (IS_ERR_VALUE(addr)) { 166 if (IS_ERR_VALUE(addr)) {
119 ret = addr; 167 ret = addr;
120 goto up_fail; 168 goto up_fail;
@@ -122,10 +170,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
122 170
123 current->mm->context.vdso = (void *)addr; 171 current->mm->context.vdso = (void *)addr;
124 172
125 ret = install_special_mapping(mm, addr, vdso_size, 173 ret = install_special_mapping(mm, addr, size,
126 VM_READ|VM_EXEC| 174 VM_READ|VM_EXEC|
127 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 175 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
128 vdso_pages); 176 pages);
129 if (ret) { 177 if (ret) {
130 current->mm->context.vdso = NULL; 178 current->mm->context.vdso = NULL;
131 goto up_fail; 179 goto up_fail;
@@ -136,6 +184,20 @@ up_fail:
136 return ret; 184 return ret;
137} 185}
138 186
187int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
188{
189 return setup_additional_pages(bprm, uses_interp, vdso_pages,
190 vdso_size);
191}
192
193#ifdef CONFIG_X86_X32_ABI
194int x32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
195{
196 return setup_additional_pages(bprm, uses_interp, vdsox32_pages,
197 vdsox32_size);
198}
199#endif
200
139static __init int vdso_setup(char *s) 201static __init int vdso_setup(char *s)
140{ 202{
141 vdso_enabled = simple_strtoul(s, NULL, 0); 203 vdso_enabled = simple_strtoul(s, NULL, 0);