diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2022-03-24 18:09:43 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-24 19:06:45 -0700 |
| commit | 90647d9d725068ad27d39f80d2b4a5150d041038 (patch) | |
| tree | 01afa8f8b9f5b7015a33aa67e399550235f6dc66 /tools/testing/selftests/vm/util.h | |
| parent | 1a9762b2d7a56e9926a22a627972423840a1aabb (diff) | |
selftest/vm: add util.h and and move helper functions there
Avoid code duplication by adding util.h. No functional change in this
patch.
Link: https://lkml.kernel.org/r/20220307054355.149820-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'tools/testing/selftests/vm/util.h')
| -rw-r--r-- | tools/testing/selftests/vm/util.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/util.h b/tools/testing/selftests/vm/util.h new file mode 100644 index 000000000000..0f0a0f345d76 --- /dev/null +++ b/tools/testing/selftests/vm/util.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __KSELFTEST_VM_UTIL_H +#define __KSELFTEST_VM_UTIL_H + +#include <stdint.h> +#include <sys/mman.h> +#include <err.h> + +#define PAGE_SHIFT 12 +#define HPAGE_SHIFT 21 + +#define PAGE_SIZE (1 << PAGE_SHIFT) +#define HPAGE_SIZE (1 << HPAGE_SHIFT) + +#define PAGEMAP_PRESENT(ent) (((ent) & (1ull << 63)) != 0) +#define PAGEMAP_PFN(ent) ((ent) & ((1ull << 55) - 1)) + + +static inline int64_t allocate_transhuge(void *ptr, int pagemap_fd) +{ + uint64_t ent[2]; + + /* drop pmd */ + if (mmap(ptr, HPAGE_SIZE, PROT_READ | PROT_WRITE, + MAP_FIXED | MAP_ANONYMOUS | + MAP_NORESERVE | MAP_PRIVATE, -1, 0) != ptr) + errx(2, "mmap transhuge"); + + if (madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE)) + err(2, "MADV_HUGEPAGE"); + + /* allocate transparent huge page */ + *(volatile void **)ptr = ptr; + + if (pread(pagemap_fd, ent, sizeof(ent), + (uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent)) + err(2, "read pagemap"); + + if (PAGEMAP_PRESENT(ent[0]) && PAGEMAP_PRESENT(ent[1]) && + PAGEMAP_PFN(ent[0]) + 1 == PAGEMAP_PFN(ent[1]) && + !(PAGEMAP_PFN(ent[0]) & ((1 << (HPAGE_SHIFT - PAGE_SHIFT)) - 1))) + return PAGEMAP_PFN(ent[0]); + + return -1; +} + +#endif |