Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=f288f32dc51042fd3a493b85b226e63f1ad3edcc
Commit:     f288f32dc51042fd3a493b85b226e63f1ad3edcc
Parent:     85a93b95dcd24023e0590ba4852ebff29208491a
Author:     Roland McGrath <[EMAIL PROTECTED]>
AuthorDate: Wed Jan 30 13:30:42 2008 +0100
Committer:  Ingo Molnar <[EMAIL PROTECTED]>
CommitDate: Wed Jan 30 13:30:42 2008 +0100

    x86 vDSO: vdso32 setup
    
    This moves arch/x86/kernel/sysenter_32.c to arch/x86/vdso/vdso32-setup.c,
    keeping all the code relating only to vDSO magic in the vdso/ subdirectory.
    This is a pure renaming, but it paves the way to consolidating the code for
    dealing with 32-bit vDSOs across CONFIG_X86_32 and CONFIG_IA32_EMULATION.
    
    Signed-off-by: Roland McGrath <[EMAIL PROTECTED]>
    Cc: Andrew Morton <[EMAIL PROTECTED]>
    Cc: Linus Torvalds <[EMAIL PROTECTED]>
    Signed-off-by: Thomas Gleixner <[EMAIL PROTECTED]>
    Signed-off-by: Ingo Molnar <[EMAIL PROTECTED]>
    Signed-off-by: Thomas Gleixner <[EMAIL PROTECTED]>
---
 arch/x86/kernel/Makefile_32   |    1 -
 arch/x86/kernel/sysenter_32.c |  344 -----------------------------------------
 arch/x86/vdso/Makefile        |    2 +-
 arch/x86/vdso/vdso32-setup.c  |  344 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 345 insertions(+), 346 deletions(-)

diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32
index 0eef822..2c9596b 100644
--- a/arch/x86/kernel/Makefile_32
+++ b/arch/x86/kernel/Makefile_32
@@ -33,7 +33,6 @@ obj-$(CONFIG_X86_NUMAQ)               += numaq_32.o
 obj-$(CONFIG_X86_SUMMIT_NUMA)  += summit_32.o
 obj-$(CONFIG_KPROBES)          += kprobes_32.o
 obj-$(CONFIG_MODULES)          += module_32.o
-obj-y                          += sysenter_32.o
 obj-$(CONFIG_ACPI_SRAT)        += srat_32.o
 obj-$(CONFIG_EFI)              += efi_32.o efi_stub_32.o
 obj-$(CONFIG_DOUBLEFAULT)      += doublefault_32.o
diff --git a/arch/x86/kernel/sysenter_32.c b/arch/x86/kernel/sysenter_32.c
deleted file mode 100644
index 85c52d2..0000000
--- a/arch/x86/kernel/sysenter_32.c
+++ /dev/null
@@ -1,344 +0,0 @@
-/*
- * (C) Copyright 2002 Linus Torvalds
- * Portions based on the vdso-randomization code from exec-shield:
- * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
- *
- * This file contains the needed initializations to support sysenter.
- */
-
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/thread_info.h>
-#include <linux/sched.h>
-#include <linux/gfp.h>
-#include <linux/string.h>
-#include <linux/elf.h>
-#include <linux/mm.h>
-#include <linux/err.h>
-#include <linux/module.h>
-
-#include <asm/cpufeature.h>
-#include <asm/msr.h>
-#include <asm/pgtable.h>
-#include <asm/unistd.h>
-#include <asm/elf.h>
-#include <asm/tlbflush.h>
-#include <asm/vdso.h>
-
-enum {
-       VDSO_DISABLED = 0,
-       VDSO_ENABLED = 1,
-       VDSO_COMPAT = 2,
-};
-
-#ifdef CONFIG_COMPAT_VDSO
-#define VDSO_DEFAULT   VDSO_COMPAT
-#else
-#define VDSO_DEFAULT   VDSO_ENABLED
-#endif
-
-/*
- * Should the kernel map a VDSO page into processes and pass its
- * address down to glibc upon exec()?
- */
-unsigned int __read_mostly vdso_enabled = VDSO_DEFAULT;
-
-EXPORT_SYMBOL_GPL(vdso_enabled);
-
-static int __init vdso_setup(char *s)
-{
-       vdso_enabled = simple_strtoul(s, NULL, 0);
-
-       return 1;
-}
-
-__setup("vdso=", vdso_setup);
-
-extern asmlinkage void sysenter_entry(void);
-
-static __init void reloc_symtab(Elf32_Ehdr *ehdr,
-                               unsigned offset, unsigned size)
-{
-       Elf32_Sym *sym = (void *)ehdr + offset;
-       unsigned nsym = size / sizeof(*sym);
-       unsigned i;
-
-       for(i = 0; i < nsym; i++, sym++) {
-               if (sym->st_shndx == SHN_UNDEF ||
-                   sym->st_shndx == SHN_ABS)
-                       continue;  /* skip */
-
-               if (sym->st_shndx > SHN_LORESERVE) {
-                       printk(KERN_INFO "VDSO: unexpected st_shndx %x\n",
-                              sym->st_shndx);
-                       continue;
-               }
-
-               switch(ELF_ST_TYPE(sym->st_info)) {
-               case STT_OBJECT:
-               case STT_FUNC:
-               case STT_SECTION:
-               case STT_FILE:
-                       sym->st_value += VDSO_HIGH_BASE;
-               }
-       }
-}
-
-static __init void reloc_dyn(Elf32_Ehdr *ehdr, unsigned offset)
-{
-       Elf32_Dyn *dyn = (void *)ehdr + offset;
-
-       for(; dyn->d_tag != DT_NULL; dyn++)
-               switch(dyn->d_tag) {
-               case DT_PLTGOT:
-               case DT_HASH:
-               case DT_STRTAB:
-               case DT_SYMTAB:
-               case DT_RELA:
-               case DT_INIT:
-               case DT_FINI:
-               case DT_REL:
-               case DT_DEBUG:
-               case DT_JMPREL:
-               case DT_VERSYM:
-               case DT_VERDEF:
-               case DT_VERNEED:
-               case DT_ADDRRNGLO ... DT_ADDRRNGHI:
-                       /* definitely pointers needing relocation */
-                       dyn->d_un.d_ptr += VDSO_HIGH_BASE;
-                       break;
-
-               case DT_ENCODING ... OLD_DT_LOOS-1:
-               case DT_LOOS ... DT_HIOS-1:
-                       /* Tags above DT_ENCODING are pointers if
-                          they're even */
-                       if (dyn->d_tag >= DT_ENCODING &&
-                           (dyn->d_tag & 1) == 0)
-                               dyn->d_un.d_ptr += VDSO_HIGH_BASE;
-                       break;
-
-               case DT_VERDEFNUM:
-               case DT_VERNEEDNUM:
-               case DT_FLAGS_1:
-               case DT_RELACOUNT:
-               case DT_RELCOUNT:
-               case DT_VALRNGLO ... DT_VALRNGHI:
-                       /* definitely not pointers */
-                       break;
-
-               case OLD_DT_LOOS ... DT_LOOS-1:
-               case DT_HIOS ... DT_VALRNGLO-1:
-               default:
-                       if (dyn->d_tag > DT_ENCODING)
-                               printk(KERN_INFO "VDSO: unexpected DT_tag %x\n",
-                                      dyn->d_tag);
-                       break;
-               }
-}
-
-static __init void relocate_vdso(Elf32_Ehdr *ehdr)
-{
-       Elf32_Phdr *phdr;
-       Elf32_Shdr *shdr;
-       int i;
-
-       BUG_ON(memcmp(ehdr->e_ident, ELFMAG, 4) != 0 ||
-              !elf_check_arch(ehdr) ||
-              ehdr->e_type != ET_DYN);
-
-       ehdr->e_entry += VDSO_HIGH_BASE;
-
-       /* rebase phdrs */
-       phdr = (void *)ehdr + ehdr->e_phoff;
-       for (i = 0; i < ehdr->e_phnum; i++) {
-               phdr[i].p_vaddr += VDSO_HIGH_BASE;
-
-               /* relocate dynamic stuff */
-               if (phdr[i].p_type == PT_DYNAMIC)
-                       reloc_dyn(ehdr, phdr[i].p_offset);
-       }
-
-       /* rebase sections */
-       shdr = (void *)ehdr + ehdr->e_shoff;
-       for(i = 0; i < ehdr->e_shnum; i++) {
-               if (!(shdr[i].sh_flags & SHF_ALLOC))
-                       continue;
-
-               shdr[i].sh_addr += VDSO_HIGH_BASE;
-
-               if (shdr[i].sh_type == SHT_SYMTAB ||
-                   shdr[i].sh_type == SHT_DYNSYM)
-                       reloc_symtab(ehdr, shdr[i].sh_offset,
-                                    shdr[i].sh_size);
-       }
-}
-
-void enable_sep_cpu(void)
-{
-       int cpu = get_cpu();
-       struct tss_struct *tss = &per_cpu(init_tss, cpu);
-
-       if (!boot_cpu_has(X86_FEATURE_SEP)) {
-               put_cpu();
-               return;
-       }
-
-       tss->x86_tss.ss1 = __KERNEL_CS;
-       tss->x86_tss.esp1 = sizeof(struct tss_struct) + (unsigned long) tss;
-       wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
-       wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.esp1, 0);
-       wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) sysenter_entry, 0);
-       put_cpu();      
-}
-
-static struct vm_area_struct gate_vma;
-
-static int __init gate_vma_init(void)
-{
-       gate_vma.vm_mm = NULL;
-       gate_vma.vm_start = FIXADDR_USER_START;
-       gate_vma.vm_end = FIXADDR_USER_END;
-       gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
-       gate_vma.vm_page_prot = __P101;
-       /*
-        * Make sure the vDSO gets into every core dump.
-        * Dumping its contents makes post-mortem fully interpretable later
-        * without matching up the same kernel and hardware config to see
-        * what PC values meant.
-        */
-       gate_vma.vm_flags |= VM_ALWAYSDUMP;
-       return 0;
-}
-
-/*
- * These symbols are defined by vsyscall.o to mark the bounds
- * of the ELF DSO images included therein.
- */
-extern const char vsyscall_int80_start, vsyscall_int80_end;
-extern const char vsyscall_sysenter_start, vsyscall_sysenter_end;
-static struct page *syscall_pages[1];
-
-static void map_compat_vdso(int map)
-{
-       static int vdso_mapped;
-
-       if (map == vdso_mapped)
-               return;
-
-       vdso_mapped = map;
-
-       __set_fixmap(FIX_VDSO, page_to_pfn(syscall_pages[0]) << PAGE_SHIFT,
-                    map ? PAGE_READONLY_EXEC : PAGE_NONE);
-
-       /* flush stray tlbs */
-       flush_tlb_all();
-}
-
-int __init sysenter_setup(void)
-{
-       void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
-       const void *vsyscall;
-       size_t vsyscall_len;
-
-       syscall_pages[0] = virt_to_page(syscall_page);
-
-       gate_vma_init();
-
-       printk("Compat vDSO mapped to %08lx.\n", __fix_to_virt(FIX_VDSO));
-
-       if (!boot_cpu_has(X86_FEATURE_SEP)) {
-               vsyscall = &vsyscall_int80_start;
-               vsyscall_len = &vsyscall_int80_end - &vsyscall_int80_start;
-       } else {
-               vsyscall = &vsyscall_sysenter_start;
-               vsyscall_len = &vsyscall_sysenter_end - 
&vsyscall_sysenter_start;
-       }
-
-       memcpy(syscall_page, vsyscall, vsyscall_len);
-       relocate_vdso(syscall_page);
-
-       return 0;
-}
-
-/* Setup a VMA at program startup for the vsyscall page */
-int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
-{
-       struct mm_struct *mm = current->mm;
-       unsigned long addr;
-       int ret = 0;
-       bool compat;
-
-       down_write(&mm->mmap_sem);
-
-       /* Test compat mode once here, in case someone
-          changes it via sysctl */
-       compat = (vdso_enabled == VDSO_COMPAT);
-
-       map_compat_vdso(compat);
-
-       if (compat)
-               addr = VDSO_HIGH_BASE;
-       else {
-               addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
-               if (IS_ERR_VALUE(addr)) {
-                       ret = addr;
-                       goto up_fail;
-               }
-
-               /*
-                * MAYWRITE to allow gdb to COW and set breakpoints
-                *
-                * Make sure the vDSO gets into every core dump.
-                * Dumping its contents makes post-mortem fully
-                * interpretable later without matching up the same
-                * kernel and hardware config to see what PC values
-                * meant.
-                */
-               ret = install_special_mapping(mm, addr, PAGE_SIZE,
-                                             VM_READ|VM_EXEC|
-                                             VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
-                                             VM_ALWAYSDUMP,
-                                             syscall_pages);
-
-               if (ret)
-                       goto up_fail;
-       }
-
-       current->mm->context.vdso = (void *)addr;
-       current_thread_info()->sysenter_return =
-               VDSO32_SYMBOL(addr, SYSENTER_RETURN);
-
-  up_fail:
-       up_write(&mm->mmap_sem);
-
-       return ret;
-}
-
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
-       if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
-               return "[vdso]";
-       return NULL;
-}
-
-struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
-{
-       struct mm_struct *mm = tsk->mm;
-
-       /* Check to see if this task was created in compat vdso mode */
-       if (mm && mm->context.vdso == (void *)VDSO_HIGH_BASE)
-               return &gate_vma;
-       return NULL;
-}
-
-int in_gate_area(struct task_struct *task, unsigned long addr)
-{
-       const struct vm_area_struct *vma = get_gate_vma(task);
-
-       return vma && addr >= vma->vm_start && addr < vma->vm_end;
-}
-
-int in_gate_area_no_task(unsigned long addr)
-{
-       return 0;
-}
diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index ca2aabf..1efe785 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -15,7 +15,7 @@ vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o vvar.o
 
 # files to link into kernel
 obj-$(VDSO64-y)                        += vma.o vdso.o
-obj-$(CONFIG_X86_32)           += vdso32.o
+obj-$(CONFIG_X86_32)           += vdso32.o vdso32-setup.o
 
 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
 
diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
new file mode 100644
index 0000000..85c52d2
--- /dev/null
+++ b/arch/x86/vdso/vdso32-setup.c
@@ -0,0 +1,344 @@
+/*
+ * (C) Copyright 2002 Linus Torvalds
+ * Portions based on the vdso-randomization code from exec-shield:
+ * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
+ *
+ * This file contains the needed initializations to support sysenter.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/thread_info.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+#include <linux/string.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/module.h>
+
+#include <asm/cpufeature.h>
+#include <asm/msr.h>
+#include <asm/pgtable.h>
+#include <asm/unistd.h>
+#include <asm/elf.h>
+#include <asm/tlbflush.h>
+#include <asm/vdso.h>
+
+enum {
+       VDSO_DISABLED = 0,
+       VDSO_ENABLED = 1,
+       VDSO_COMPAT = 2,
+};
+
+#ifdef CONFIG_COMPAT_VDSO
+#define VDSO_DEFAULT   VDSO_COMPAT
+#else
+#define VDSO_DEFAULT   VDSO_ENABLED
+#endif
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso_enabled = VDSO_DEFAULT;
+
+EXPORT_SYMBOL_GPL(vdso_enabled);
+
+static int __init vdso_setup(char *s)
+{
+       vdso_enabled = simple_strtoul(s, NULL, 0);
+
+       return 1;
+}
+
+__setup("vdso=", vdso_setup);
+
+extern asmlinkage void sysenter_entry(void);
+
+static __init void reloc_symtab(Elf32_Ehdr *ehdr,
+                               unsigned offset, unsigned size)
+{
+       Elf32_Sym *sym = (void *)ehdr + offset;
+       unsigned nsym = size / sizeof(*sym);
+       unsigned i;
+
+       for(i = 0; i < nsym; i++, sym++) {
+               if (sym->st_shndx == SHN_UNDEF ||
+                   sym->st_shndx == SHN_ABS)
+                       continue;  /* skip */
+
+               if (sym->st_shndx > SHN_LORESERVE) {
+                       printk(KERN_INFO "VDSO: unexpected st_shndx %x\n",
+                              sym->st_shndx);
+                       continue;
+               }
+
+               switch(ELF_ST_TYPE(sym->st_info)) {
+               case STT_OBJECT:
+               case STT_FUNC:
+               case STT_SECTION:
+               case STT_FILE:
+                       sym->st_value += VDSO_HIGH_BASE;
+               }
+       }
+}
+
+static __init void reloc_dyn(Elf32_Ehdr *ehdr, unsigned offset)
+{
+       Elf32_Dyn *dyn = (void *)ehdr + offset;
+
+       for(; dyn->d_tag != DT_NULL; dyn++)
+               switch(dyn->d_tag) {
+               case DT_PLTGOT:
+               case DT_HASH:
+               case DT_STRTAB:
+               case DT_SYMTAB:
+               case DT_RELA:
+               case DT_INIT:
+               case DT_FINI:
+               case DT_REL:
+               case DT_DEBUG:
+               case DT_JMPREL:
+               case DT_VERSYM:
+               case DT_VERDEF:
+               case DT_VERNEED:
+               case DT_ADDRRNGLO ... DT_ADDRRNGHI:
+                       /* definitely pointers needing relocation */
+                       dyn->d_un.d_ptr += VDSO_HIGH_BASE;
+                       break;
+
+               case DT_ENCODING ... OLD_DT_LOOS-1:
+               case DT_LOOS ... DT_HIOS-1:
+                       /* Tags above DT_ENCODING are pointers if
+                          they're even */
+                       if (dyn->d_tag >= DT_ENCODING &&
+                           (dyn->d_tag & 1) == 0)
+                               dyn->d_un.d_ptr += VDSO_HIGH_BASE;
+                       break;
+
+               case DT_VERDEFNUM:
+               case DT_VERNEEDNUM:
+               case DT_FLAGS_1:
+               case DT_RELACOUNT:
+               case DT_RELCOUNT:
+               case DT_VALRNGLO ... DT_VALRNGHI:
+                       /* definitely not pointers */
+                       break;
+
+               case OLD_DT_LOOS ... DT_LOOS-1:
+               case DT_HIOS ... DT_VALRNGLO-1:
+               default:
+                       if (dyn->d_tag > DT_ENCODING)
+                               printk(KERN_INFO "VDSO: unexpected DT_tag %x\n",
+                                      dyn->d_tag);
+                       break;
+               }
+}
+
+static __init void relocate_vdso(Elf32_Ehdr *ehdr)
+{
+       Elf32_Phdr *phdr;
+       Elf32_Shdr *shdr;
+       int i;
+
+       BUG_ON(memcmp(ehdr->e_ident, ELFMAG, 4) != 0 ||
+              !elf_check_arch(ehdr) ||
+              ehdr->e_type != ET_DYN);
+
+       ehdr->e_entry += VDSO_HIGH_BASE;
+
+       /* rebase phdrs */
+       phdr = (void *)ehdr + ehdr->e_phoff;
+       for (i = 0; i < ehdr->e_phnum; i++) {
+               phdr[i].p_vaddr += VDSO_HIGH_BASE;
+
+               /* relocate dynamic stuff */
+               if (phdr[i].p_type == PT_DYNAMIC)
+                       reloc_dyn(ehdr, phdr[i].p_offset);
+       }
+
+       /* rebase sections */
+       shdr = (void *)ehdr + ehdr->e_shoff;
+       for(i = 0; i < ehdr->e_shnum; i++) {
+               if (!(shdr[i].sh_flags & SHF_ALLOC))
+                       continue;
+
+               shdr[i].sh_addr += VDSO_HIGH_BASE;
+
+               if (shdr[i].sh_type == SHT_SYMTAB ||
+                   shdr[i].sh_type == SHT_DYNSYM)
+                       reloc_symtab(ehdr, shdr[i].sh_offset,
+                                    shdr[i].sh_size);
+       }
+}
+
+void enable_sep_cpu(void)
+{
+       int cpu = get_cpu();
+       struct tss_struct *tss = &per_cpu(init_tss, cpu);
+
+       if (!boot_cpu_has(X86_FEATURE_SEP)) {
+               put_cpu();
+               return;
+       }
+
+       tss->x86_tss.ss1 = __KERNEL_CS;
+       tss->x86_tss.esp1 = sizeof(struct tss_struct) + (unsigned long) tss;
+       wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
+       wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.esp1, 0);
+       wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) sysenter_entry, 0);
+       put_cpu();      
+}
+
+static struct vm_area_struct gate_vma;
+
+static int __init gate_vma_init(void)
+{
+       gate_vma.vm_mm = NULL;
+       gate_vma.vm_start = FIXADDR_USER_START;
+       gate_vma.vm_end = FIXADDR_USER_END;
+       gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
+       gate_vma.vm_page_prot = __P101;
+       /*
+        * Make sure the vDSO gets into every core dump.
+        * Dumping its contents makes post-mortem fully interpretable later
+        * without matching up the same kernel and hardware config to see
+        * what PC values meant.
+        */
+       gate_vma.vm_flags |= VM_ALWAYSDUMP;
+       return 0;
+}
+
+/*
+ * These symbols are defined by vsyscall.o to mark the bounds
+ * of the ELF DSO images included therein.
+ */
+extern const char vsyscall_int80_start, vsyscall_int80_end;
+extern const char vsyscall_sysenter_start, vsyscall_sysenter_end;
+static struct page *syscall_pages[1];
+
+static void map_compat_vdso(int map)
+{
+       static int vdso_mapped;
+
+       if (map == vdso_mapped)
+               return;
+
+       vdso_mapped = map;
+
+       __set_fixmap(FIX_VDSO, page_to_pfn(syscall_pages[0]) << PAGE_SHIFT,
+                    map ? PAGE_READONLY_EXEC : PAGE_NONE);
+
+       /* flush stray tlbs */
+       flush_tlb_all();
+}
+
+int __init sysenter_setup(void)
+{
+       void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
+       const void *vsyscall;
+       size_t vsyscall_len;
+
+       syscall_pages[0] = virt_to_page(syscall_page);
+
+       gate_vma_init();
+
+       printk("Compat vDSO mapped to %08lx.\n", __fix_to_virt(FIX_VDSO));
+
+       if (!boot_cpu_has(X86_FEATURE_SEP)) {
+               vsyscall = &vsyscall_int80_start;
+               vsyscall_len = &vsyscall_int80_end - &vsyscall_int80_start;
+       } else {
+               vsyscall = &vsyscall_sysenter_start;
+               vsyscall_len = &vsyscall_sysenter_end - 
&vsyscall_sysenter_start;
+       }
+
+       memcpy(syscall_page, vsyscall, vsyscall_len);
+       relocate_vdso(syscall_page);
+
+       return 0;
+}
+
+/* Setup a VMA at program startup for the vsyscall page */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
+{
+       struct mm_struct *mm = current->mm;
+       unsigned long addr;
+       int ret = 0;
+       bool compat;
+
+       down_write(&mm->mmap_sem);
+
+       /* Test compat mode once here, in case someone
+          changes it via sysctl */
+       compat = (vdso_enabled == VDSO_COMPAT);
+
+       map_compat_vdso(compat);
+
+       if (compat)
+               addr = VDSO_HIGH_BASE;
+       else {
+               addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+               if (IS_ERR_VALUE(addr)) {
+                       ret = addr;
+                       goto up_fail;
+               }
+
+               /*
+                * MAYWRITE to allow gdb to COW and set breakpoints
+                *
+                * Make sure the vDSO gets into every core dump.
+                * Dumping its contents makes post-mortem fully
+                * interpretable later without matching up the same
+                * kernel and hardware config to see what PC values
+                * meant.
+                */
+               ret = install_special_mapping(mm, addr, PAGE_SIZE,
+                                             VM_READ|VM_EXEC|
+                                             VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+                                             VM_ALWAYSDUMP,
+                                             syscall_pages);
+
+               if (ret)
+                       goto up_fail;
+       }
+
+       current->mm->context.vdso = (void *)addr;
+       current_thread_info()->sysenter_return =
+               VDSO32_SYMBOL(addr, SYSENTER_RETURN);
+
+  up_fail:
+       up_write(&mm->mmap_sem);
+
+       return ret;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+       if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
+               return "[vdso]";
+       return NULL;
+}
+
+struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
+{
+       struct mm_struct *mm = tsk->mm;
+
+       /* Check to see if this task was created in compat vdso mode */
+       if (mm && mm->context.vdso == (void *)VDSO_HIGH_BASE)
+               return &gate_vma;
+       return NULL;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long addr)
+{
+       const struct vm_area_struct *vma = get_gate_vma(task);
+
+       return vma && addr >= vma->vm_start && addr < vma->vm_end;
+}
+
+int in_gate_area_no_task(unsigned long addr)
+{
+       return 0;
+}
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