Re: [PATCH 14/15] swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Date: 2022-03-14 23:14:14
Also in:
linux-arm-kernel, linux-hyperv, linux-iommu, linux-mips, linux-pci, linux-riscv, linux-s390, xen-devel
On 3/14/22 3:31 AM, Christoph Hellwig wrote:
quoted hunk ↗ jump to hunk
@@ -314,6 +293,7 @@ void __init swiotlb_init(bool addressing_limit, unsigned int flags) int swiotlb_init_late(size_t size, gfp_t gfp_mask, int (*remap)(void *tlb, unsigned long nslabs)) { + struct io_tlb_mem *mem = &io_tlb_default_mem; unsigned long nslabs = ALIGN(size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE); unsigned long bytes; unsigned char *vstart = NULL;@@ -355,33 +335,28 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask, (PAGE_SIZE << order) >> 20); nslabs = SLABS_PER_PAGE << order; } - rc = swiotlb_late_init_with_tbl(vstart, nslabs); - if (rc) - free_pages((unsigned long)vstart, order); - - return rc; -} - -int -swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) -{ - struct io_tlb_mem *mem = &io_tlb_default_mem; - unsigned long bytes = nslabs << IO_TLB_SHIFT; - if (swiotlb_force_disable) - return 0; + if (remap) + rc = remap(vstart, nslabs); + if (rc) { + free_pages((unsigned long)vstart, order); - /* protect against double initialization */ - if (WARN_ON_ONCE(mem->nslabs)) - return -ENOMEM; + /* Min is 2MB */ + if (nslabs <= 1024) + return rc; + nslabs = max(1024UL, ALIGN(nslabs >> 1, IO_TLB_SEGSIZE)); + goto retry; + }
We now end up with two attempts to remap. I think this second one is what we want since it solves the problem I pointed in previous patch. -boris