diff options
Diffstat (limited to 'arch/s390/kernel/vdso.c')
| -rw-r--r-- | arch/s390/kernel/vdso.c | 102 |
1 files changed, 30 insertions, 72 deletions
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c index f4e1e4580b77..a7eed8bf3959 100644 --- a/arch/s390/kernel/vdso.c +++ b/arch/s390/kernel/vdso.c @@ -6,41 +6,41 @@ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) */ -#include <linux/init.h> +#include <linux/binfmts.h> +#include <linux/compat.h> +#include <linux/elf.h> #include <linux/errno.h> -#include <linux/sched.h> +#include <linux/init.h> #include <linux/kernel.h> #include <linux/mm.h> -#include <linux/smp.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/memblock.h> -#include <linux/compat.h> -#include <linux/binfmts.h> +#include <linux/smp.h> #include <vdso/datapage.h> -#include <asm/asm-offsets.h> -#include <asm/processor.h> -#include <asm/mmu.h> -#include <asm/mmu_context.h> -#include <asm/sections.h> #include <asm/vdso.h> -#include <asm/facility.h> -#include <asm/timex.h> extern char vdso64_start[], vdso64_end[]; static unsigned int vdso_pages; static struct page **vdso_pagelist; -/* - * Should the kernel map a VDSO page into processes and pass its - * address down to glibc upon exec()? - */ +static union { + struct vdso_data data[CS_BASES]; + u8 page[PAGE_SIZE]; +} vdso_data_store __page_aligned_data; + +struct vdso_data *vdso_data = vdso_data_store.data; + unsigned int __read_mostly vdso_enabled = 1; +static int __init vdso_setup(char *str) +{ + bool enabled; + + if (!kstrtobool(str, &enabled)) + vdso_enabled = enabled; + return 1; +} +__setup("vdso=", vdso_setup); + static vm_fault_t vdso_fault(const struct vm_special_mapping *sm, struct vm_area_struct *vma, struct vm_fault *vmf) { @@ -56,7 +56,6 @@ static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *vma) { current->mm->context.vdso_base = vma->vm_start; - return 0; } @@ -66,25 +65,6 @@ static const struct vm_special_mapping vdso_mapping = { .mremap = vdso_mremap, }; -static int __init vdso_setup(char *str) -{ - bool enabled; - - if (!kstrtobool(str, &enabled)) - vdso_enabled = enabled; - return 1; -} -__setup("vdso=", vdso_setup); - -/* - * The vdso data page - */ -static union { - struct vdso_data data[CS_BASES]; - u8 page[PAGE_SIZE]; -} vdso_data_store __page_aligned_data; -struct vdso_data *vdso_data = vdso_data_store.data; - int vdso_getcpu_init(void) { set_tod_programmable_field(smp_processor_id()); @@ -92,10 +72,6 @@ int vdso_getcpu_init(void) } early_initcall(vdso_getcpu_init); /* Must be called before SMP init */ -/* - * 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 uses_interp) { struct mm_struct *mm = current->mm; @@ -103,25 +79,14 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) unsigned long vdso_base; int rc; - if (!vdso_enabled) - return 0; - - if (is_compat_task()) + if (!vdso_enabled || is_compat_task()) return 0; - - /* - * 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. - */ if (mmap_write_lock_killable(mm)) return -EINTR; vdso_base = get_unmapped_area(NULL, 0, vdso_pages << PAGE_SHIFT, 0, 0); - if (IS_ERR_VALUE(vdso_base)) { - rc = vdso_base; - goto out_up; - } - + rc = vdso_base; + if (IS_ERR_VALUE(vdso_base)) + goto out; /* * our vma flags don't have VM_WRITE so by default, the process * isn't allowed to write those pages. @@ -136,15 +101,12 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) VM_READ|VM_EXEC| VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, &vdso_mapping); - if (IS_ERR(vma)) { - rc = PTR_ERR(vma); - goto out_up; - } - + rc = PTR_ERR(vma); + if (IS_ERR(vma)) + goto out; current->mm->context.vdso_base = vdso_base; rc = 0; - -out_up: +out: mmap_write_unlock(mm); return rc; } @@ -153,9 +115,7 @@ static int __init vdso_init(void) { int i; - /* Calculate the size of the vDSO */ vdso_pages = ((vdso64_end - vdso64_start) >> PAGE_SHIFT) + 1; - /* Make sure pages are in the correct state */ vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *), GFP_KERNEL); @@ -170,9 +130,7 @@ static int __init vdso_init(void) } vdso_pagelist[vdso_pages - 1] = virt_to_page(vdso_data); vdso_pagelist[vdso_pages] = NULL; - get_page(virt_to_page(vdso_data)); - return 0; } arch_initcall(vdso_init); |