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-rw-r--r--Documentation/vm/hugepage-mmap.c91
1 files changed, 0 insertions, 91 deletions
diff --git a/Documentation/vm/hugepage-mmap.c b/Documentation/vm/hugepage-mmap.c
deleted file mode 100644
index db0dd9a..0000000
--- a/Documentation/vm/hugepage-mmap.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- * hugepage-mmap:
- *
- * Example of using huge page memory in a user application using the mmap
- * system call. Before running this application, make sure that the
- * administrator has mounted the hugetlbfs filesystem (on some directory
- * like /mnt) using the command mount -t hugetlbfs nodev /mnt. In this
- * example, the app is requesting memory of size 256MB that is backed by
- * huge pages.
- *
- * For the ia64 architecture, the Linux kernel reserves Region number 4 for
- * huge pages. That means that if one requires a fixed address, a huge page
- * aligned address starting with 0x800000... will be required. If a fixed
- * address is not required, the kernel will select an address in the proper
- * range.
- * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-
-#define FILE_NAME "/mnt/hugepagefile"
-#define LENGTH (256UL*1024*1024)
-#define PROTECTION (PROT_READ | PROT_WRITE)
-
-/* Only ia64 requires this */
-#ifdef __ia64__
-#define ADDR (void *)(0x8000000000000000UL)
-#define FLAGS (MAP_SHARED | MAP_FIXED)
-#else
-#define ADDR (void *)(0x0UL)
-#define FLAGS (MAP_SHARED)
-#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;
- int fd;
-
- fd = open(FILE_NAME, O_CREAT | O_RDWR, 0755);
- if (fd < 0) {
- perror("Open failed");
- exit(1);
- }
-
- addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0);
- if (addr == MAP_FAILED) {
- perror("mmap");
- unlink(FILE_NAME);
- exit(1);
- }
-
- printf("Returned address is %p\n", addr);
- check_bytes(addr);
- write_bytes(addr);
- read_bytes(addr);
-
- munmap(addr, LENGTH);
- close(fd);
- unlink(FILE_NAME);
-
- return 0;
-}