fuse: use kvmalloc to allocate array of pipe_buffer structs.
The amount of pipe->buffers is basically controlled by userspace by
fcntl(... F_SETPIPE_SZ ...) so it could be large. High order allocations
could be slow (if memory is heavily fragmented) or may fail if the order
is larger than PAGE_ALLOC_COSTLY_ORDER.
Since the 'bufs' doesn't need to be physically contiguous, use
the kvmalloc_array() to allocate memory. If high order
page isn't available, the kvamalloc*() will fallback to 0-order.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index de3d273..1050c1c 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1373,8 +1373,8 @@
if (!fud)
return -EPERM;
- bufs = kmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
- GFP_KERNEL);
+ bufs = kvmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
+ GFP_KERNEL);
if (!bufs)
return -ENOMEM;
@@ -1407,7 +1407,7 @@
for (; page_nr < cs.nr_segs; page_nr++)
put_page(bufs[page_nr].page);
- kfree(bufs);
+ kvfree(bufs);
return ret;
}
@@ -1957,8 +1957,8 @@
pipe_lock(pipe);
- bufs = kmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
- GFP_KERNEL);
+ bufs = kvmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
+ GFP_KERNEL);
if (!bufs) {
pipe_unlock(pipe);
return -ENOMEM;
@@ -2017,7 +2017,7 @@
pipe_buf_release(pipe, &bufs[idx]);
out:
- kfree(bufs);
+ kvfree(bufs);
return ret;
}