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6f6a841fb7
PAGE_SIZE is not 4096 in many configurations, particularly ppc64 uses 64K
pages in majority of cases.
Add helpers to detect PAGE_SIZE and PAGE_SHIFT dynamically.
Without this tests are broken w.r.t reading /proc/self/pagemap
if (pread(pagemap_fd, ent, sizeof(ent),
(uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent))
err(2, "read pagemap");
Link: https://lkml.kernel.org/r/20220307054355.149820-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
69 lines
1.6 KiB
C
69 lines
1.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __KSELFTEST_VM_UTIL_H
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#define __KSELFTEST_VM_UTIL_H
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#include <stdint.h>
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#include <sys/mman.h>
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#include <err.h>
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#include <string.h> /* ffsl() */
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#include <unistd.h> /* _SC_PAGESIZE */
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static unsigned int __page_size;
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static unsigned int __page_shift;
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static inline unsigned int page_size(void)
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{
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if (!__page_size)
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__page_size = sysconf(_SC_PAGESIZE);
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return __page_size;
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}
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static inline unsigned int page_shift(void)
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{
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if (!__page_shift)
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__page_shift = (ffsl(page_size()) - 1);
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return __page_shift;
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}
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#define PAGE_SHIFT (page_shift())
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#define PAGE_SIZE (page_size())
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/*
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* On ppc64 this will only work with radix 2M hugepage size
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*/
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#define HPAGE_SHIFT 21
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#define HPAGE_SIZE (1 << HPAGE_SHIFT)
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#define PAGEMAP_PRESENT(ent) (((ent) & (1ull << 63)) != 0)
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#define PAGEMAP_PFN(ent) ((ent) & ((1ull << 55) - 1))
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static inline int64_t allocate_transhuge(void *ptr, int pagemap_fd)
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{
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uint64_t ent[2];
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/* drop pmd */
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if (mmap(ptr, HPAGE_SIZE, PROT_READ | PROT_WRITE,
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MAP_FIXED | MAP_ANONYMOUS |
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MAP_NORESERVE | MAP_PRIVATE, -1, 0) != ptr)
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errx(2, "mmap transhuge");
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if (madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE))
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err(2, "MADV_HUGEPAGE");
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/* allocate transparent huge page */
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*(volatile void **)ptr = ptr;
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if (pread(pagemap_fd, ent, sizeof(ent),
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(uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent))
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err(2, "read pagemap");
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if (PAGEMAP_PRESENT(ent[0]) && PAGEMAP_PRESENT(ent[1]) &&
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PAGEMAP_PFN(ent[0]) + 1 == PAGEMAP_PFN(ent[1]) &&
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!(PAGEMAP_PFN(ent[0]) & ((1 << (HPAGE_SHIFT - PAGE_SHIFT)) - 1)))
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return PAGEMAP_PFN(ent[0]);
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return -1;
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}
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#endif
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