From d05f3169c0fbca16132ec7c2be71685c6de638b5 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 24 May 2011 17:11:44 -0700 Subject: mm: make expand_downwards() symmetrical with expand_upwards() Currently we have expand_upwards exported while expand_downwards is accessible only via expand_stack or expand_stack_downwards. check_stack_guard_page is a nice example of the asymmetry. It uses expand_stack for VM_GROWSDOWN while expand_upwards is called for VM_GROWSUP case. Let's clean this up by exporting both functions and make those names consistent. Let's use expand_{upwards,downwards} because expanding doesn't always involve stack manipulation (an example is ia64_do_page_fault which uses expand_upwards for registers backing store expansion). expand_downwards has to be defined for both CONFIG_STACK_GROWS{UP,DOWN} because get_arg_page calls the downwards version in the early process initialization phase for growsup configuration. Signed-off-by: Michal Hocko Acked-by: Hugh Dickins Cc: James Bottomley Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mm.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include/linux/mm.h') diff --git a/include/linux/mm.h b/include/linux/mm.h index e173cd297d88..d2948af126ca 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1518,15 +1518,17 @@ unsigned long ra_submit(struct file_ra_state *ra, struct address_space *mapping, struct file *filp); -/* Do stack extension */ +/* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ extern int expand_stack(struct vm_area_struct *vma, unsigned long address); + +/* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */ +extern int expand_downwards(struct vm_area_struct *vma, + unsigned long address); #if VM_GROWSUP extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); #else #define expand_upwards(vma, address) do { } while (0) #endif -extern int expand_stack_downwards(struct vm_area_struct *vma, - unsigned long address); /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); -- cgit v1.2.3