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-rw-r--r--Documentation/vm/map_hugetlb.c77
1 files changed, 0 insertions, 77 deletions
diff --git a/Documentation/vm/map_hugetlb.c b/Documentation/vm/map_hugetlb.c
deleted file mode 100644
index eda1a6d..0000000
--- a/Documentation/vm/map_hugetlb.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
- * Example of using hugepage memory in a user application using the mmap
- * system call with MAP_HUGETLB flag. Before running this program make
- * sure the administrator has allocated enough default sized huge pages
- * to cover the 256 MB allocation.
- *
- * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages.
- * That means the addresses starting with 0x800000... will need to be
- * specified. Specifying a fixed address is not required on ppc64, i386
- * or x86_64.
- */
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-
-#define LENGTH (256UL*1024*1024)
-#define PROTECTION (PROT_READ | PROT_WRITE)
-
-#ifndef MAP_HUGETLB
-#define MAP_HUGETLB 0x40000 /* arch specific */
-#endif
-
-/* Only ia64 requires this */
-#ifdef __ia64__
-#define ADDR (void *)(0x8000000000000000UL)
-#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
-#else
-#define ADDR (void *)(0x0UL)
-#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
-#endif
-
-static void check_bytes(char *addr)
-{
- printf("First hex is %x\n", *((unsigned int *)addr));
-}
-
-static void write_bytes(char *addr)
-{
- unsigned long i;
-
- for (i = 0; i < LENGTH; i++)
- *(addr + i) = (char)i;
-}
-
-static void read_bytes(char *addr)
-{
- unsigned long i;
-
- check_bytes(addr);
- for (i = 0; i < LENGTH; i++)
- if (*(addr + i) != (char)i) {
- printf("Mismatch at %lu\n", i);
- break;
- }
-}
-
-int main(void)
-{
- void *addr;
-
- addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, 0, 0);
- if (addr == MAP_FAILED) {
- perror("mmap");
- exit(1);
- }
-
- printf("Returned address is %p\n", addr);
- check_bytes(addr);
- write_bytes(addr);
- read_bytes(addr);
-
- munmap(addr, LENGTH);
-
- return 0;
-}