Commit 0c6874a6 authored Aug 01, 2023 by Petr Tesarik Committed by Christoph Hellwig Aug 01, 2023

swiotlb: bail out of swiotlb_init_late() if swiotlb is already allocated



If swiotlb is allocated, immediately return 0, so callers do not have to
check io_tlb_default_mem.nslabs explicitly.

Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

parent 3fa6456e

arch/arm/xen/mm.c

+4 −6

Original line number	Diff line number	Diff line
		@@ -125,12 +125,10 @@ static int __init xen_mm_init(void)
		return 0;

		/* we can work with the default swiotlb */
		if (!io_tlb_default_mem.nslabs) {
		rc = swiotlb_init_late(swiotlb_size_or_default(),
		xen_swiotlb_gfp(), NULL);
		if (rc < 0)
		return rc;
		}

		cflush.op = 0;
		cflush.a.dev_bus_addr = 0;

kernel/dma/swiotlb.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -384,6 +384,9 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask,
		bool retried = false;
		int rc = 0;

		if (io_tlb_default_mem.nslabs)
		return 0;

		if (swiotlb_force_disable)
		return 0;