diff options
| author | Sven Schnelle <svens@linux.ibm.com> | 2022-04-06 08:35:26 +0200 |
|---|---|---|
| committer | Heiko Carstens <hca@linux.ibm.com> | 2022-04-25 13:54:14 +0200 |
| commit | 57761da4dc5cd60bed2c81ba0edb7495c3c740b8 (patch) | |
| tree | abbdfb74d74e91abed372c2ad22f3ca29d7061d2 | |
| parent | f2f47d0ef72c30622e62471903ea19446ea79ee2 (diff) | |
s390/vdso: move vdso mapping to its own function
This is a preparation patch for adding vdso randomization to s390.
It adds a function vdso_size(), which will be used later in calculating
the STACK_TOP value. It also moves the vdso mapping into a new function
vdso_map(), to keep the code similar to other architectures.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/processor.h | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/vdso.c | 24 |
2 files changed, 20 insertions, 5 deletions
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index ff1e25d515a8..a3ab8cbcc5e4 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -83,6 +83,7 @@ void cpu_detect_mhz_feature(void); extern const struct seq_operations cpuinfo_op; extern void execve_tail(void); extern void __bpon(void); +unsigned long vdso_size(void); /* * User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit. diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c index 99694260cac9..22cb727d5821 100644 --- a/arch/s390/kernel/vdso.c +++ b/arch/s390/kernel/vdso.c @@ -160,10 +160,9 @@ int vdso_getcpu_init(void) } early_initcall(vdso_getcpu_init); /* Must be called before SMP init */ -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +static int map_vdso(unsigned long addr, unsigned long vdso_mapping_len) { - unsigned long vdso_text_len, vdso_mapping_len; - unsigned long vvar_start, vdso_text_start; + unsigned long vvar_start, vdso_text_start, vdso_text_len; struct vm_special_mapping *vdso_mapping; struct mm_struct *mm = current->mm; struct vm_area_struct *vma; @@ -180,8 +179,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) vdso_text_len = vdso64_end - vdso64_start; vdso_mapping = &vdso64_mapping; } - vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE; - vvar_start = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); + vvar_start = get_unmapped_area(NULL, addr, vdso_mapping_len, 0, 0); rc = vvar_start; if (IS_ERR_VALUE(vvar_start)) goto out; @@ -210,6 +208,22 @@ out: return rc; } +unsigned long vdso_size(void) +{ + unsigned long size = VVAR_NR_PAGES * PAGE_SIZE; + + if (is_compat_task()) + size += vdso32_end - vdso32_start; + else + size += vdso64_end - vdso64_start; + return PAGE_ALIGN(size); +} + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + return map_vdso(0, vdso_size()); +} + static struct page ** __init vdso_setup_pages(void *start, void *end) { int pages = (end - start) >> PAGE_SHIFT; |