At this moment, we have following task_size-related things:
- TASK_SIZE_OF() macro, which is unused;
- current->mm->task_size which is used in half and TASK_SIZE() macro
which is used in the other half of code
- TIF_ADDR32, which is used to detect 32-bit address space and is
x86-specific, where some other arches misused TIF_32BIT
- personality ADDR_LIMIT_32BIT, which is used on arm/alpha
- ADDR_LIMIT_3GB, which is x86-specific and can be used to change
running task's TASK_SIZE 3GB <-> 4GB
This patches set removes unused definition of TASK_SIZE_OF (1),
defines TASK_SIZE macro as current->mm->task_size (3).
I would suggest define TASK_SIZE this way in generic version,
but currently I test it only on x86.
It also frees thread info flag (2) and adds arch_prctl()
on x86_64 to get/set current virtual address space size - as
it's needed by now only for CRIU, hide it under CHECKPOINT_RESTORE
config.
Hope those patches will help to clean task_size-related code
at least a bit (and helps me to restore vaddr limits).
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Dmitry Safonov (4):
mm: remove unused TASK_SIZE_OF()
x86/thread_info: kill TIF_ADDR32 in favour of ADDR_LIMIT_32BIT
x86/mm: define TASK_SIZE as current->mm->task_size
x86/arch_prctl: add ARCH_{GET,SET}_TASK_SIZE
arch/arm64/include/asm/memory.h | 2 --
arch/mips/include/asm/processor.h | 3 ---
arch/parisc/include/asm/processor.h | 3 +--
arch/powerpc/include/asm/processor.h | 3 +--
arch/s390/include/asm/processor.h | 3 +--
arch/sparc/include/asm/processor_64.h | 3 ---
arch/x86/include/asm/elf.h | 7 +++++--
arch/x86/include/asm/processor.h | 19 +++++++++----------
arch/x86/include/asm/thread_info.h | 4 +---
arch/x86/include/uapi/asm/prctl.h | 3 +++
arch/x86/kernel/process_64.c | 17 +++++++++++++++--
arch/x86/kernel/sys_x86_64.c | 4 ++--
arch/x86/um/asm/segment.h | 2 +-
arch/x86/xen/mmu.c | 4 ++--
fs/exec.c | 17 +++++++++++------
include/linux/sched.h | 4 ----
16 files changed, 52 insertions(+), 46 deletions(-)
--
2.11.0
