Now that NULL locked doesn't have a special meaning we can just make it
non-NULL in all cases and remove the special tests.
get_user_pages() and pin_user_pages() can safely pass in a locked = 1
get_user_pages_remote) and pin_user_pages_remote() can swap in a local
variable for locked if NULL is passed.
Remove all the NULL checks.
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
---
mm/gup.c | 30 ++++++++++++++++++++----------
1 file changed, 20 insertions(+), 10 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c
index 4c360fb05cf3e4..1ccfff759a29eb 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -930,8 +930,8 @@ static int faultin_page(struct vm_area_struct *vma,
* mmap lock in the page fault handler. Sanity check this.
*/
WARN_ON_ONCE(fault_flags & FAULT_FLAG_RETRY_NOWAIT);
- if (locked)
- *locked = 0;
+ *locked = 0;
+
/*
* We should do the same as VM_FAULT_RETRY, but let's not
* return -EBUSY since that's not reflecting the reality of
@@ -951,7 +951,7 @@ static int faultin_page(struct vm_area_struct *vma,
}
if (ret & VM_FAULT_RETRY) {
- if (locked && !(fault_flags & FAULT_FLAG_RETRY_NOWAIT))
+ if (!(fault_flags & FAULT_FLAG_RETRY_NOWAIT))
*locked = 0;
return -EBUSY;
}
@@ -1121,7 +1121,7 @@ static long __get_user_pages(struct mm_struct *mm,
i = follow_hugetlb_page(mm, vma, pages, vmas,
&start, &nr_pages, i,
gup_flags, locked);
- if (locked && *locked == 0) {
+ if (!*locked) {
/*
* We've got a VM_FAULT_RETRY
* and we've lost mmap_lock.
@@ -1345,7 +1345,7 @@ static __always_inline long __get_user_pages_locked(struct mm_struct *mm,
* The internal caller expects GUP to manage the lock internally and the
* lock must be released when this returns.
*/
- if (locked && !*locked) {
+ if (!*locked) {
if (mmap_read_lock_killable(mm))
return -EAGAIN;
lock_dropped = true;
@@ -1679,7 +1679,7 @@ static long __get_user_pages_locked(struct mm_struct *mm, unsigned long start,
* The internal caller expects GUP to manage the lock internally and the
* lock must be released when this returns.
*/
- if (locked && !*locked) {
+ if (!*locked) {
if (mmap_read_lock_killable(mm))
return -EAGAIN;
must_unlock = true;
@@ -2218,11 +2218,14 @@ long get_user_pages_remote(struct mm_struct *mm,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
{
+ int local_locked = 1;
+
if (!is_valid_gup_args(pages, vmas, locked, &gup_flags,
FOLL_TOUCH | FOLL_REMOTE))
return -EINVAL;
- return __get_user_pages_locked(mm, start, nr_pages, pages, vmas, locked,
+ return __get_user_pages_locked(mm, start, nr_pages, pages, vmas,
+ locked ? locked : &local_locked,
gup_flags);
}
EXPORT_SYMBOL(get_user_pages_remote);
@@ -2257,11 +2260,13 @@ long get_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas)
{
+ int locked = 1;
+
if (!is_valid_gup_args(pages, vmas, NULL, &gup_flags, FOLL_TOUCH))
return -EINVAL;
return __get_user_pages_locked(current->mm, start, nr_pages, pages,
- vmas, NULL, gup_flags);
+ vmas, &locked, gup_flags);
}
EXPORT_SYMBOL(get_user_pages);
@@ -3154,10 +3159,13 @@ long pin_user_pages_remote(struct mm_struct *mm,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas, int *locked)
{
+ int local_locked = 1;
+
if (!is_valid_gup_args(pages, vmas, locked, &gup_flags,
FOLL_PIN | FOLL_TOUCH | FOLL_REMOTE))
return 0;
- return __gup_longterm_locked(mm, start, nr_pages, pages, vmas, locked,
+ return __gup_longterm_locked(mm, start, nr_pages, pages, vmas,
+ locked ? locked : &local_locked,
gup_flags);
}
EXPORT_SYMBOL(pin_user_pages_remote);
@@ -3183,10 +3191,12 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
struct vm_area_struct **vmas)
{
+ int locked = 1;
+
if (!is_valid_gup_args(pages, vmas, NULL, &gup_flags, FOLL_PIN))
return 0;
return __gup_longterm_locked(current->mm, start, nr_pages,
- pages, vmas, NULL, gup_flags);
+ pages, vmas, &locked, gup_flags);
}
EXPORT_SYMBOL(pin_user_pages);
--
2.39.0
