[PATCH] platform: goldfish: pipe: use get_user_pages_unlocked()

From: Lorenzo Stoakes
Date: Tue Nov 01 2016 - 15:44:19 EST


Moving from get_user_pages() to get_user_pages_unlocked() simplifies the code
and takes advantage of VM_FAULT_RETRY functionality when faulting in pages.

Signed-off-by: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
---
drivers/platform/goldfish/goldfish_pipe.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c
index 1aba2c7..2b21033 100644
--- a/drivers/platform/goldfish/goldfish_pipe.c
+++ b/drivers/platform/goldfish/goldfish_pipe.c
@@ -308,10 +308,8 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
* returns a small amount, then there's no need to pin that
* much memory to the process.
*/
- down_read(&current->mm->mmap_sem);
- ret = get_user_pages(address, 1, is_write ? 0 : FOLL_WRITE,
- &page, NULL);
- up_read(&current->mm->mmap_sem);
+ ret = get_user_pages_unlocked(address, 1, &page,
+ is_write ? 0 : FOLL_WRITE);
if (ret < 0)
break;

--
2.10.2