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>
This commit is contained in:
Petr Tesarik 2023-08-01 08:23:56 +02:00 committed by Christoph Hellwig
parent 3fa6456ebe
commit 0c6874a6ac
2 changed files with 7 additions and 6 deletions

View File

@ -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;
}
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;

View File

@ -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;