scsi: st: Replace GFP_ATOMIC with GFP_KERNEL in new_tape_buffer

new_tape_buffer() is never called in atomic context. new_tape_buffer()
is only called by st_probe(), which is only set as ".probe" in struct
scsi_driver.

Despite never getting called from atomic context, new_tape_buffer()
calls kzalloc() with GFP_ATOMIC, which does not sleep for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, which
can sleep and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Jia-Ju Bai 2018-04-10 20:38:42 +08:00 committed by Martin K. Petersen
parent 1f618aac2f
commit 4011f07660

View file

@ -3878,7 +3878,7 @@ static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
{
struct st_buffer *tb;
tb = kzalloc(sizeof(struct st_buffer), GFP_ATOMIC);
tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
if (!tb) {
printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
return NULL;
@ -3889,7 +3889,7 @@ static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
tb->buffer_size = 0;
tb->reserved_pages = kzalloc(max_sg * sizeof(struct page *),
GFP_ATOMIC);
GFP_KERNEL);
if (!tb->reserved_pages) {
kfree(tb);
return NULL;