From 5b56d49fc31dbb0487e14ead790fc81ca9fb2c99 Mon Sep 17 00:00:00 2001 From: Lorenzo Stoakes Date: Wed, 14 Dec 2016 15:06:52 -0800 Subject: mm: add locked parameter to get_user_pages_remote() Patch series "mm: unexport __get_user_pages_unlocked()". This patch series continues the cleanup of get_user_pages*() functions taking advantage of the fact we can now pass gup_flags as we please. It firstly adds an additional 'locked' parameter to get_user_pages_remote() to allow for its callers to utilise VM_FAULT_RETRY functionality. This is necessary as the invocation of __get_user_pages_unlocked() in process_vm_rw_single_vec() makes use of this and no other existing higher level function would allow it to do so. Secondly existing callers of __get_user_pages_unlocked() are replaced with the appropriate higher-level replacement - get_user_pages_unlocked() if the current task and memory descriptor are referenced, or get_user_pages_remote() if other task/memory descriptors are referenced (having acquiring mmap_sem.) This patch (of 2): Add a int *locked parameter to get_user_pages_remote() to allow VM_FAULT_RETRY faulting behaviour similar to get_user_pages_[un]locked(). Taking into account the previous adjustments to get_user_pages*() functions allowing for the passing of gup_flags, we are now in a position where __get_user_pages_unlocked() need only be exported for his ability to allow VM_FAULT_RETRY behaviour, this adjustment allows us to subsequently unexport __get_user_pages_unlocked() as well as allowing for future flexibility in the use of get_user_pages_remote(). [sfr@canb.auug.org.au: merge fix for get_user_pages_remote API change] Link: http://lkml.kernel.org/r/20161122210511.024ec341@canb.auug.org.au Link: http://lkml.kernel.org/r/20161027095141.2569-2-lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes Acked-by: Michal Hocko Cc: Jan Kara Cc: Hugh Dickins Cc: Dave Hansen Cc: Rik van Riel Cc: Mel Gorman Cc: Paolo Bonzini Cc: Radim Krcmar Signed-off-by: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/events/uprobes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index f9ec9add2164..215871bda3a2 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -301,7 +301,7 @@ int uprobe_write_opcode(struct mm_struct *mm, unsigned long vaddr, retry: /* Read the page with vaddr into memory */ ret = get_user_pages_remote(NULL, mm, vaddr, 1, FOLL_FORCE, &old_page, - &vma); + &vma, NULL); if (ret <= 0) return ret; @@ -1712,7 +1712,7 @@ static int is_trap_at_addr(struct mm_struct *mm, unsigned long vaddr) * essentially a kernel access to the memory. */ result = get_user_pages_remote(NULL, mm, vaddr, 1, FOLL_FORCE, &page, - NULL); + NULL, NULL); if (result < 0) return result; -- cgit v1.2.3-58-ga151