This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / arch / powerpc / kernel / vdso.c
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
new file mode 100644 (file)
index 0000000..a6042f7
--- /dev/null
@@ -0,0 +1,749 @@
+/*
+ *    Copyright (C) 2004 Benjamin Herrenschmidt, IBM Corp.
+ *                      <benh@kernel.crashing.org>
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+#include <linux/security.h>
+#include <linux/bootmem.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/lmb.h>
+#include <asm/machdep.h>
+#include <asm/cputable.h>
+#include <asm/sections.h>
+#include <asm/firmware.h>
+#include <asm/vdso.h>
+#include <asm/vdso_datapage.h>
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(fmt...) printk(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+/* Max supported size for symbol names */
+#define MAX_SYMNAME    64
+
+extern char vdso32_start, vdso32_end;
+static void *vdso32_kbase = &vdso32_start;
+unsigned int vdso32_pages;
+unsigned long vdso32_sigtramp;
+unsigned long vdso32_rt_sigtramp;
+
+#ifdef CONFIG_PPC64
+extern char vdso64_start, vdso64_end;
+static void *vdso64_kbase = &vdso64_start;
+unsigned int vdso64_pages;
+unsigned long vdso64_rt_sigtramp;
+#endif /* CONFIG_PPC64 */
+
+/*
+ * The vdso data page (aka. systemcfg for old ppc64 fans) is here.
+ * Once the early boot kernel code no longer needs to muck around
+ * with it, it will become dynamically allocated
+ */
+static union {
+       struct vdso_data        data;
+       u8                      page[PAGE_SIZE];
+} vdso_data_store __attribute__((__section__(".data.page_aligned")));
+struct vdso_data *vdso_data = &vdso_data_store.data;
+
+/* Format of the patch table */
+struct vdso_patch_def
+{
+       unsigned long   ftr_mask, ftr_value;
+       const char      *gen_name;
+       const char      *fix_name;
+};
+
+/* Table of functions to patch based on the CPU type/revision
+ *
+ * Currently, we only change sync_dicache to do nothing on processors
+ * with a coherent icache
+ */
+static struct vdso_patch_def vdso_patches[] = {
+       {
+               CPU_FTR_COHERENT_ICACHE, CPU_FTR_COHERENT_ICACHE,
+               "__kernel_sync_dicache", "__kernel_sync_dicache_p5"
+       },
+       {
+               CPU_FTR_USE_TB, 0,
+               "__kernel_gettimeofday", NULL
+       },
+};
+
+/*
+ * Some infos carried around for each of them during parsing at
+ * boot time.
+ */
+struct lib32_elfinfo
+{
+       Elf32_Ehdr      *hdr;           /* ptr to ELF */
+       Elf32_Sym       *dynsym;        /* ptr to .dynsym section */
+       unsigned long   dynsymsize;     /* size of .dynsym section */
+       char            *dynstr;        /* ptr to .dynstr section */
+       unsigned long   text;           /* offset of .text section in .so */
+};
+
+struct lib64_elfinfo
+{
+       Elf64_Ehdr      *hdr;
+       Elf64_Sym       *dynsym;
+       unsigned long   dynsymsize;
+       char            *dynstr;
+       unsigned long   text;
+};
+
+
+#ifdef __DEBUG
+static void dump_one_vdso_page(struct page *pg, struct page *upg)
+{
+       printk("kpg: %p (c:%d,f:%08lx)", __va(page_to_pfn(pg) << PAGE_SHIFT),
+              page_count(pg),
+              pg->flags);
+       if (upg/* && pg != upg*/) {
+               printk(" upg: %p (c:%d,f:%08lx)", __va(page_to_pfn(upg)
+                                                      << PAGE_SHIFT),
+                      page_count(upg),
+                      upg->flags);
+       }
+       printk("\n");
+}
+
+static void dump_vdso_pages(struct vm_area_struct * vma)
+{
+       int i;
+
+       if (!vma || test_thread_flag(TIF_32BIT)) {
+               printk("vDSO32 @ %016lx:\n", (unsigned long)vdso32_kbase);
+               for (i=0; i<vdso32_pages; i++) {
+                       struct page *pg = virt_to_page(vdso32_kbase +
+                                                      i*PAGE_SIZE);
+                       struct page *upg = (vma && vma->vm_mm) ?
+                               follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
+                               : NULL;
+                       dump_one_vdso_page(pg, upg);
+               }
+       }
+       if (!vma || !test_thread_flag(TIF_32BIT)) {
+               printk("vDSO64 @ %016lx:\n", (unsigned long)vdso64_kbase);
+               for (i=0; i<vdso64_pages; i++) {
+                       struct page *pg = virt_to_page(vdso64_kbase +
+                                                      i*PAGE_SIZE);
+                       struct page *upg = (vma && vma->vm_mm) ?
+                               follow_page(vma, vma->vm_start + i*PAGE_SIZE, 0)
+                               : NULL;
+                       dump_one_vdso_page(pg, upg);
+               }
+       }
+}
+#endif /* DEBUG */
+
+/*
+ * Keep a dummy vma_close for now, it will prevent VMA merging.
+ */
+static void vdso_vma_close(struct vm_area_struct * vma)
+{
+}
+
+/*
+ * Our nopage() function, maps in the actual vDSO kernel pages, they will
+ * be mapped read-only by do_no_page(), and eventually COW'ed, either
+ * right away for an initial write access, or by do_wp_page().
+ */
+static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
+                                    unsigned long address, int *type)
+{
+       unsigned long offset = address - vma->vm_start;
+       struct page *pg;
+#ifdef CONFIG_PPC64
+       void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
+               vdso64_kbase : vdso32_kbase;
+#else
+       void *vbase = vdso32_kbase;
+#endif
+
+       DBG("vdso_vma_nopage(current: %s, address: %016lx, off: %lx)\n",
+           current->comm, address, offset);
+
+       if (address < vma->vm_start || address > vma->vm_end)
+               return NOPAGE_SIGBUS;
+
+       /*
+        * Last page is systemcfg.
+        */
+       if ((vma->vm_end - address) <= PAGE_SIZE)
+               pg = virt_to_page(vdso_data);
+       else
+               pg = virt_to_page(vbase + offset);
+
+       get_page(pg);
+       DBG(" ->page count: %d\n", page_count(pg));
+
+       return pg;
+}
+
+static struct vm_operations_struct vdso_vmops = {
+       .close  = vdso_vma_close,
+       .nopage = vdso_vma_nopage,
+};
+
+/*
+ * This is called from binfmt_elf, we create the special vma for the
+ * vDSO and insert it into the mm struct tree
+ */
+int arch_setup_additional_pages(struct linux_binprm *bprm,
+                               int executable_stack, unsigned long start_code,
+                               unsigned long interp_map_address)
+{
+       struct mm_struct *mm = current->mm;
+       struct vm_area_struct *vma;
+       unsigned long vdso_pages;
+       unsigned long vdso_base;
+
+#ifdef CONFIG_PPC64
+       if (test_thread_flag(TIF_32BIT)) {
+               vdso_pages = vdso32_pages;
+               vdso_base = VDSO32_MBASE;
+       } else {
+               vdso_pages = vdso64_pages;
+               vdso_base = VDSO64_MBASE;
+       }
+#else
+       vdso_pages = vdso32_pages;
+       vdso_base = VDSO32_MBASE;
+#endif
+
+       current->thread.vdso_base = 0;
+
+       /* vDSO has a problem and was disabled, just don't "enable" it for the
+        * process
+        */
+       if (vdso_pages == 0)
+               return 0;
+
+       vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
+       if (vma == NULL)
+               return -ENOMEM;
+
+       memset(vma, 0, sizeof(*vma));
+
+       /* Add a page to the vdso size for the data page */
+       vdso_pages ++;
+
+       /*
+        * pick a base address for the vDSO in process space. We try to put it
+        * at vdso_base which is the "natural" base for it, but we might fail
+        * and end up putting it elsewhere.
+        */
+       vdso_base = get_unmapped_area(NULL, vdso_base,
+                                     vdso_pages << PAGE_SHIFT, 0, 0);
+       if (vdso_base & ~PAGE_MASK) {
+               kmem_cache_free(vm_area_cachep, vma);
+               return (int)vdso_base;
+       }
+
+       current->thread.vdso_base = vdso_base;
+
+       vma->vm_mm = mm;
+       vma->vm_start = current->thread.vdso_base;
+       vma->vm_end = vma->vm_start + (vdso_pages << PAGE_SHIFT);
+
+       /*
+        * our vma flags don't have VM_WRITE so by default, the process isn't
+        * allowed to write those pages.
+        * gdb can break that with ptrace interface, and thus trigger COW on
+        * those pages but it's then your responsibility to never do that on
+        * the "data" page of the vDSO or you'll stop getting kernel updates
+        * and your nice userland gettimeofday will be totally dead.
+        * It's fine to use that for setting breakpoints in the vDSO code
+        * pages though
+        */
+       vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
+       vma->vm_flags |= mm->def_flags;
+       vma->vm_page_prot = protection_map[vma->vm_flags & 0x7];
+       vma->vm_ops = &vdso_vmops;
+
+       down_write(&mm->mmap_sem);
+       if (insert_vm_struct(mm, vma)) {
+               up_write(&mm->mmap_sem);
+               kmem_cache_free(vm_area_cachep, vma);
+               return -ENOMEM;
+       }
+       mm->total_vm += (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+       up_write(&mm->mmap_sem);
+
+       return 0;
+}
+
+static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
+                                 unsigned long *size)
+{
+       Elf32_Shdr *sechdrs;
+       unsigned int i;
+       char *secnames;
+
+       /* Grab section headers and strings so we can tell who is who */
+       sechdrs = (void *)ehdr + ehdr->e_shoff;
+       secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+       /* Find the section they want */
+       for (i = 1; i < ehdr->e_shnum; i++) {
+               if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
+                       if (size)
+                               *size = sechdrs[i].sh_size;
+                       return (void *)ehdr + sechdrs[i].sh_offset;
+               }
+       }
+       *size = 0;
+       return NULL;
+}
+
+static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
+                                       const char *symname)
+{
+       unsigned int i;
+       char name[MAX_SYMNAME], *c;
+
+       for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
+               if (lib->dynsym[i].st_name == 0)
+                       continue;
+               strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
+                       MAX_SYMNAME);
+               c = strchr(name, '@');
+               if (c)
+                       *c = 0;
+               if (strcmp(symname, name) == 0)
+                       return &lib->dynsym[i];
+       }
+       return NULL;
+}
+
+/* Note that we assume the section is .text and the symbol is relative to
+ * the library base
+ */
+static unsigned long __init find_function32(struct lib32_elfinfo *lib,
+                                           const char *symname)
+{
+       Elf32_Sym *sym = find_symbol32(lib, symname);
+
+       if (sym == NULL) {
+               printk(KERN_WARNING "vDSO32: function %s not found !\n",
+                      symname);
+               return 0;
+       }
+       return sym->st_value - VDSO32_LBASE;
+}
+
+static int vdso_do_func_patch32(struct lib32_elfinfo *v32,
+                               struct lib64_elfinfo *v64,
+                               const char *orig, const char *fix)
+{
+       Elf32_Sym *sym32_gen, *sym32_fix;
+
+       sym32_gen = find_symbol32(v32, orig);
+       if (sym32_gen == NULL) {
+               printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
+               return -1;
+       }
+       if (fix == NULL) {
+               sym32_gen->st_name = 0;
+               return 0;
+       }
+       sym32_fix = find_symbol32(v32, fix);
+       if (sym32_fix == NULL) {
+               printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
+               return -1;
+       }
+       sym32_gen->st_value = sym32_fix->st_value;
+       sym32_gen->st_size = sym32_fix->st_size;
+       sym32_gen->st_info = sym32_fix->st_info;
+       sym32_gen->st_other = sym32_fix->st_other;
+       sym32_gen->st_shndx = sym32_fix->st_shndx;
+
+       return 0;
+}
+
+
+#ifdef CONFIG_PPC64
+
+static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
+                                 unsigned long *size)
+{
+       Elf64_Shdr *sechdrs;
+       unsigned int i;
+       char *secnames;
+
+       /* Grab section headers and strings so we can tell who is who */
+       sechdrs = (void *)ehdr + ehdr->e_shoff;
+       secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+       /* Find the section they want */
+       for (i = 1; i < ehdr->e_shnum; i++) {
+               if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
+                       if (size)
+                               *size = sechdrs[i].sh_size;
+                       return (void *)ehdr + sechdrs[i].sh_offset;
+               }
+       }
+       if (size)
+               *size = 0;
+       return NULL;
+}
+
+static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
+                                       const char *symname)
+{
+       unsigned int i;
+       char name[MAX_SYMNAME], *c;
+
+       for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
+               if (lib->dynsym[i].st_name == 0)
+                       continue;
+               strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
+                       MAX_SYMNAME);
+               c = strchr(name, '@');
+               if (c)
+                       *c = 0;
+               if (strcmp(symname, name) == 0)
+                       return &lib->dynsym[i];
+       }
+       return NULL;
+}
+
+/* Note that we assume the section is .text and the symbol is relative to
+ * the library base
+ */
+static unsigned long __init find_function64(struct lib64_elfinfo *lib,
+                                           const char *symname)
+{
+       Elf64_Sym *sym = find_symbol64(lib, symname);
+
+       if (sym == NULL) {
+               printk(KERN_WARNING "vDSO64: function %s not found !\n",
+                      symname);
+               return 0;
+       }
+#ifdef VDS64_HAS_DESCRIPTORS
+       return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
+               VDSO64_LBASE;
+#else
+       return sym->st_value - VDSO64_LBASE;
+#endif
+}
+
+static int vdso_do_func_patch64(struct lib32_elfinfo *v32,
+                               struct lib64_elfinfo *v64,
+                               const char *orig, const char *fix)
+{
+       Elf64_Sym *sym64_gen, *sym64_fix;
+
+       sym64_gen = find_symbol64(v64, orig);
+       if (sym64_gen == NULL) {
+               printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
+               return -1;
+       }
+       if (fix == NULL) {
+               sym64_gen->st_name = 0;
+               return 0;
+       }
+       sym64_fix = find_symbol64(v64, fix);
+       if (sym64_fix == NULL) {
+               printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
+               return -1;
+       }
+       sym64_gen->st_value = sym64_fix->st_value;
+       sym64_gen->st_size = sym64_fix->st_size;
+       sym64_gen->st_info = sym64_fix->st_info;
+       sym64_gen->st_other = sym64_fix->st_other;
+       sym64_gen->st_shndx = sym64_fix->st_shndx;
+
+       return 0;
+}
+
+#endif /* CONFIG_PPC64 */
+
+
+static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
+                                       struct lib64_elfinfo *v64)
+{
+       void *sect;
+
+       /*
+        * Locate symbol tables & text section
+        */
+
+       v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
+       v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
+       if (v32->dynsym == NULL || v32->dynstr == NULL) {
+               printk(KERN_ERR "vDSO32: required symbol section not found\n");
+               return -1;
+       }
+       sect = find_section32(v32->hdr, ".text", NULL);
+       if (sect == NULL) {
+               printk(KERN_ERR "vDSO32: the .text section was not found\n");
+               return -1;
+       }
+       v32->text = sect - vdso32_kbase;
+
+#ifdef CONFIG_PPC64
+       v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
+       v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
+       if (v64->dynsym == NULL || v64->dynstr == NULL) {
+               printk(KERN_ERR "vDSO64: required symbol section not found\n");
+               return -1;
+       }
+       sect = find_section64(v64->hdr, ".text", NULL);
+       if (sect == NULL) {
+               printk(KERN_ERR "vDSO64: the .text section was not found\n");
+               return -1;
+       }
+       v64->text = sect - vdso64_kbase;
+#endif /* CONFIG_PPC64 */
+
+       return 0;
+}
+
+static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
+                                         struct lib64_elfinfo *v64)
+{
+       /*
+        * Find signal trampolines
+        */
+
+#ifdef CONFIG_PPC64
+       vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
+#endif
+       vdso32_sigtramp    = find_function32(v32, "__kernel_sigtramp32");
+       vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
+}
+
+static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
+                                      struct lib64_elfinfo *v64)
+{
+       Elf32_Sym *sym32;
+#ifdef CONFIG_PPC64
+       Elf64_Sym *sym64;
+
+               sym64 = find_symbol64(v64, "__kernel_datapage_offset");
+       if (sym64 == NULL) {
+               printk(KERN_ERR "vDSO64: Can't find symbol "
+                      "__kernel_datapage_offset !\n");
+               return -1;
+       }
+       *((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
+               (vdso64_pages << PAGE_SHIFT) -
+               (sym64->st_value - VDSO64_LBASE);
+#endif /* CONFIG_PPC64 */
+
+       sym32 = find_symbol32(v32, "__kernel_datapage_offset");
+       if (sym32 == NULL) {
+               printk(KERN_ERR "vDSO32: Can't find symbol "
+                      "__kernel_datapage_offset !\n");
+               return -1;
+       }
+       *((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
+               (vdso32_pages << PAGE_SHIFT) -
+               (sym32->st_value - VDSO32_LBASE);
+
+       return 0;
+}
+
+static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
+                                      struct lib64_elfinfo *v64)
+{
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(vdso_patches); i++) {
+               struct vdso_patch_def *patch = &vdso_patches[i];
+               int match = (cur_cpu_spec->cpu_features & patch->ftr_mask)
+                       == patch->ftr_value;
+               if (!match)
+                       continue;
+
+               DBG("replacing %s with %s...\n", patch->gen_name,
+                   patch->fix_name ? "NONE" : patch->fix_name);
+
+               /*
+                * Patch the 32 bits and 64 bits symbols. Note that we do not
+                * patch the "." symbol on 64 bits.
+                * It would be easy to do, but doesn't seem to be necessary,
+                * patching the OPD symbol is enough.
+                */
+               vdso_do_func_patch32(v32, v64, patch->gen_name,
+                                    patch->fix_name);
+#ifdef CONFIG_PPC64
+               vdso_do_func_patch64(v32, v64, patch->gen_name,
+                                    patch->fix_name);
+#endif /* CONFIG_PPC64 */
+       }
+
+       return 0;
+}
+
+
+static __init int vdso_setup(void)
+{
+       struct lib32_elfinfo    v32;
+       struct lib64_elfinfo    v64;
+
+       v32.hdr = vdso32_kbase;
+#ifdef CONFIG_PPC64
+       v64.hdr = vdso64_kbase;
+#endif
+       if (vdso_do_find_sections(&v32, &v64))
+               return -1;
+
+       if (vdso_fixup_datapage(&v32, &v64))
+               return -1;
+
+       if (vdso_fixup_alt_funcs(&v32, &v64))
+               return -1;
+
+       vdso_setup_trampolines(&v32, &v64);
+
+       return 0;
+}
+
+/*
+ * Called from setup_arch to initialize the bitmap of available
+ * syscalls in the systemcfg page
+ */
+static void __init vdso_setup_syscall_map(void)
+{
+       unsigned int i;
+       extern unsigned long *sys_call_table;
+       extern unsigned long sys_ni_syscall;
+
+
+       for (i = 0; i < __NR_syscalls; i++) {
+#ifdef CONFIG_PPC64
+               if (sys_call_table[i*2] != sys_ni_syscall)
+                       vdso_data->syscall_map_64[i >> 5] |=
+                               0x80000000UL >> (i & 0x1f);
+               if (sys_call_table[i*2+1] != sys_ni_syscall)
+                       vdso_data->syscall_map_32[i >> 5] |=
+                               0x80000000UL >> (i & 0x1f);
+#else /* CONFIG_PPC64 */
+               if (sys_call_table[i] != sys_ni_syscall)
+                       vdso_data->syscall_map_32[i >> 5] |=
+                               0x80000000UL >> (i & 0x1f);
+#endif /* CONFIG_PPC64 */
+       }
+}
+
+
+void __init vdso_init(void)
+{
+       int i;
+
+#ifdef CONFIG_PPC64
+       /*
+        * Fill up the "systemcfg" stuff for backward compatiblity
+        */
+       strcpy(vdso_data->eye_catcher, "SYSTEMCFG:PPC64");
+       vdso_data->version.major = SYSTEMCFG_MAJOR;
+       vdso_data->version.minor = SYSTEMCFG_MINOR;
+       vdso_data->processor = mfspr(SPRN_PVR);
+       /*
+        * Fake the old platform number for pSeries and iSeries and add
+        * in LPAR bit if necessary
+        */
+       vdso_data->platform = machine_is(iseries) ? 0x200 : 0x100;
+       if (firmware_has_feature(FW_FEATURE_LPAR))
+               vdso_data->platform |= 1;
+       vdso_data->physicalMemorySize = lmb_phys_mem_size();
+       vdso_data->dcache_size = ppc64_caches.dsize;
+       vdso_data->dcache_line_size = ppc64_caches.dline_size;
+       vdso_data->icache_size = ppc64_caches.isize;
+       vdso_data->icache_line_size = ppc64_caches.iline_size;
+
+       /*
+        * Calculate the size of the 64 bits vDSO
+        */
+       vdso64_pages = (&vdso64_end - &vdso64_start) >> PAGE_SHIFT;
+       DBG("vdso64_kbase: %p, 0x%x pages\n", vdso64_kbase, vdso64_pages);
+#endif /* CONFIG_PPC64 */
+
+
+       /*
+        * Calculate the size of the 32 bits vDSO
+        */
+       vdso32_pages = (&vdso32_end - &vdso32_start) >> PAGE_SHIFT;
+       DBG("vdso32_kbase: %p, 0x%x pages\n", vdso32_kbase, vdso32_pages);
+
+
+       /*
+        * Setup the syscall map in the vDOS
+        */
+       vdso_setup_syscall_map();
+       /*
+        * Initialize the vDSO images in memory, that is do necessary
+        * fixups of vDSO symbols, locate trampolines, etc...
+        */
+       if (vdso_setup()) {
+               printk(KERN_ERR "vDSO setup failure, not enabled !\n");
+               vdso32_pages = 0;
+#ifdef CONFIG_PPC64
+               vdso64_pages = 0;
+#endif
+               return;
+       }
+
+       /* Make sure pages are in the correct state */
+       for (i = 0; i < vdso32_pages; i++) {
+               struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
+               ClearPageReserved(pg);
+               get_page(pg);
+
+       }
+#ifdef CONFIG_PPC64
+       for (i = 0; i < vdso64_pages; i++) {
+               struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
+               ClearPageReserved(pg);
+               get_page(pg);
+       }
+#endif /* CONFIG_PPC64 */
+
+       get_page(virt_to_page(vdso_data));
+}
+
+int in_gate_area_no_task(unsigned long addr)
+{
+       return 0;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long addr)
+{
+       return 0;
+}
+
+struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
+{
+       return NULL;
+}
+