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>
This commit is contained in:
Andrey Ryabinin 2018-07-17 19:00:34 +03:00 committed by Miklos Szeredi
parent a64ba10f65
commit d6d931adce
1 changed files with 6 additions and 6 deletions

View File

@ -1373,7 +1373,7 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
if (!fud)
return -EPERM;
bufs = kmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
bufs = kvmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
GFP_KERNEL);
if (!bufs)
return -ENOMEM;
@ -1407,7 +1407,7 @@ out:
for (; page_nr < cs.nr_segs; page_nr++)
put_page(bufs[page_nr].page);
kfree(bufs);
kvfree(bufs);
return ret;
}
@ -1957,7 +1957,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
pipe_lock(pipe);
bufs = kmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
bufs = kvmalloc_array(pipe->buffers, sizeof(struct pipe_buffer),
GFP_KERNEL);
if (!bufs) {
pipe_unlock(pipe);
@ -2017,7 +2017,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
pipe_buf_release(pipe, &bufs[idx]);
out:
kfree(bufs);
kvfree(bufs);
return ret;
}