[PATCH v2 29/34] mm/process_vm_access.c: convert put_page() to put_user_page*()

john.hubbard
2019-08-04T22:51:38Z

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christopher Yeoh <cyeoh@au1.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jann Horn <jann@thejh.net>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
---
mm/process_vm_access.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index 357aa7bef6c0..4d29d54ec93f 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -96,7 +96,7 @@ static int process_vm_rw_single_vec(unsigned long addr,
flags |= FOLL_WRITE;

while (!rc && nr_pages && iov_iter_count(iter)) {
- int pages = min(nr_pages, max_pages_per_loop);
+ int pinned_pages = min(nr_pages, max_pages_per_loop);
int locked = 1;
size_t bytes;

@@ -106,14 +106,15 @@ static int process_vm_rw_single_vec(unsigned long addr,
* current/current->mm
*/
down_read(&mm->mmap_sem);
- pages = get_user_pages_remote(task, mm, pa, pages, flags,
- process_pages, NULL, &locked);
+ pinned_pages = get_user_pages_remote(task, mm, pa, pinned_pages,
+ flags, process_pages, NULL,
+ &locked);
if (locked)
up_read(&mm->mmap_sem);
- if (pages <= 0)
+ if (pinned_pages <= 0)
return -EFAULT;

- bytes = pages * PAGE_SIZE - start_offset;
+ bytes = pinned_pages * PAGE_SIZE - start_offset;
if (bytes > len)
bytes = len;

@@ -122,10 +123,9 @@ static int process_vm_rw_single_vec(unsigned long addr,
vm_write);
len -= bytes;
start_offset = 0;
- nr_pages -= pages;
- pa += pages * PAGE_SIZE;
- while (pages)
- put_page(process_pages[--pages]);
+ nr_pages -= pinned_pages;
+ pa += pinned_pages * PAGE_SIZE;
+ put_user_pages(process_pages, pinned_pages);
}

return rc;
--
2.22.0