From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- tools/testing/nvdimm/dax-dev.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 tools/testing/nvdimm/dax-dev.c (limited to 'tools/testing/nvdimm/dax-dev.c') diff --git a/tools/testing/nvdimm/dax-dev.c b/tools/testing/nvdimm/dax-dev.c new file mode 100644 index 000000000..fb342a8c9 --- /dev/null +++ b/tools/testing/nvdimm/dax-dev.c @@ -0,0 +1,39 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2016, Intel Corporation. + */ +#include "test/nfit_test.h" +#include +#include "../../../drivers/dax/dax-private.h" + +phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, + unsigned long size) +{ + int i; + + for (i = 0; i < dev_dax->nr_range; i++) { + struct dev_dax_range *dax_range = &dev_dax->ranges[i]; + struct range *range = &dax_range->range; + unsigned long long pgoff_end; + phys_addr_t addr; + + pgoff_end = dax_range->pgoff + PHYS_PFN(range_len(range)) - 1; + if (pgoff < dax_range->pgoff || pgoff > pgoff_end) + continue; + addr = PFN_PHYS(pgoff - dax_range->pgoff) + range->start; + if (addr + size - 1 <= range->end) { + if (get_nfit_res(addr)) { + struct page *page; + + if (dev_dax->region->align > PAGE_SIZE) + return -1; + + page = vmalloc_to_page((void *)addr); + return PFN_PHYS(page_to_pfn(page)); + } + return addr; + } + break; + } + return -1; +} -- cgit v1.3.1