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Diffstat (limited to 'tools/testing/selftests/mm/write_to_hugetlbfs.c')
-rw-r--r--tools/testing/selftests/mm/write_to_hugetlbfs.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/write_to_hugetlbfs.c b/tools/testing/selftests/mm/write_to_hugetlbfs.c
new file mode 100644
index 000000000000..6a2caba19ee1
--- /dev/null
+++ b/tools/testing/selftests/mm/write_to_hugetlbfs.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This program reserves and uses hugetlb memory, supporting a bunch of
+ * scenarios needed by the charged_reserved_hugetlb.sh test.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/shm.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+/* Global definitions. */
+enum method {
+ HUGETLBFS,
+ MMAP_MAP_HUGETLB,
+ SHM,
+ MAX_METHOD
+};
+
+
+/* Global variables. */
+static const char *self;
+static char *shmaddr;
+static int shmid;
+
+/*
+ * Show usage and exit.
+ */
+static void exit_usage(void)
+{
+ printf("Usage: %s -p <path to hugetlbfs file> -s <size to map> "
+ "[-m <0=hugetlbfs | 1=mmap(MAP_HUGETLB)>] [-l] [-r] "
+ "[-o] [-w] [-n]\n",
+ self);
+ exit(EXIT_FAILURE);
+}
+
+void sig_handler(int signo)
+{
+ printf("Received %d.\n", signo);
+ if (signo == SIGINT) {
+ printf("Deleting the memory\n");
+ if (shmdt((const void *)shmaddr) != 0) {
+ perror("Detach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(4);
+ }
+
+ shmctl(shmid, IPC_RMID, NULL);
+ printf("Done deleting the memory\n");
+ }
+ exit(2);
+}
+
+int main(int argc, char **argv)
+{
+ int fd = 0;
+ int key = 0;
+ int *ptr = NULL;
+ int c = 0;
+ int size = 0;
+ char path[256] = "";
+ enum method method = MAX_METHOD;
+ int want_sleep = 0, private = 0;
+ int populate = 0;
+ int write = 0;
+ int reserve = 1;
+
+ if (signal(SIGINT, sig_handler) == SIG_ERR)
+ err(1, "\ncan't catch SIGINT\n");
+
+ /* Parse command-line arguments. */
+ setvbuf(stdout, NULL, _IONBF, 0);
+ self = argv[0];
+
+ while ((c = getopt(argc, argv, "s:p:m:owlrn")) != -1) {
+ switch (c) {
+ case 's':
+ size = atoi(optarg);
+ break;
+ case 'p':
+ strncpy(path, optarg, sizeof(path));
+ break;
+ case 'm':
+ if (atoi(optarg) >= MAX_METHOD) {
+ errno = EINVAL;
+ perror("Invalid -m.");
+ exit_usage();
+ }
+ method = atoi(optarg);
+ break;
+ case 'o':
+ populate = 1;
+ break;
+ case 'w':
+ write = 1;
+ break;
+ case 'l':
+ want_sleep = 1;
+ break;
+ case 'r':
+ private
+ = 1;
+ break;
+ case 'n':
+ reserve = 0;
+ break;
+ default:
+ errno = EINVAL;
+ perror("Invalid arg");
+ exit_usage();
+ }
+ }
+
+ if (strncmp(path, "", sizeof(path)) != 0) {
+ printf("Writing to this path: %s\n", path);
+ } else {
+ errno = EINVAL;
+ perror("path not found");
+ exit_usage();
+ }
+
+ if (size != 0) {
+ printf("Writing this size: %d\n", size);
+ } else {
+ errno = EINVAL;
+ perror("size not found");
+ exit_usage();
+ }
+
+ if (!populate)
+ printf("Not populating.\n");
+ else
+ printf("Populating.\n");
+
+ if (!write)
+ printf("Not writing to memory.\n");
+
+ if (method == MAX_METHOD) {
+ errno = EINVAL;
+ perror("-m Invalid");
+ exit_usage();
+ } else
+ printf("Using method=%d\n", method);
+
+ if (!private)
+ printf("Shared mapping.\n");
+ else
+ printf("Private mapping.\n");
+
+ if (!reserve)
+ printf("NO_RESERVE mapping.\n");
+ else
+ printf("RESERVE mapping.\n");
+
+ switch (method) {
+ case HUGETLBFS:
+ printf("Allocating using HUGETLBFS.\n");
+ fd = open(path, O_CREAT | O_RDWR, 0777);
+ if (fd == -1)
+ err(1, "Failed to open file.");
+
+ ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ (private ? MAP_PRIVATE : MAP_SHARED) |
+ (populate ? MAP_POPULATE : 0) |
+ (reserve ? 0 : MAP_NORESERVE),
+ fd, 0);
+
+ if (ptr == MAP_FAILED) {
+ close(fd);
+ err(1, "Error mapping the file");
+ }
+ break;
+ case MMAP_MAP_HUGETLB:
+ printf("Allocating using MAP_HUGETLB.\n");
+ ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ (private ? (MAP_PRIVATE | MAP_ANONYMOUS) :
+ MAP_SHARED) |
+ MAP_HUGETLB | (populate ? MAP_POPULATE : 0) |
+ (reserve ? 0 : MAP_NORESERVE),
+ -1, 0);
+
+ if (ptr == MAP_FAILED)
+ err(1, "mmap");
+
+ printf("Returned address is %p\n", ptr);
+ break;
+ case SHM:
+ printf("Allocating using SHM.\n");
+ shmid = shmget(key, size,
+ SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+ if (shmid < 0) {
+ shmid = shmget(++key, size,
+ SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+ if (shmid < 0)
+ err(1, "shmget");
+ }
+ printf("shmid: 0x%x, shmget key:%d\n", shmid, key);
+
+ ptr = shmat(shmid, NULL, 0);
+ if (ptr == (int *)-1) {
+ perror("Shared memory attach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(2);
+ }
+ printf("shmaddr: %p\n", ptr);
+
+ break;
+ default:
+ errno = EINVAL;
+ err(1, "Invalid method.");
+ }
+
+ if (write) {
+ printf("Writing to memory.\n");
+ memset(ptr, 1, size);
+ }
+
+ if (want_sleep) {
+ /* Signal to caller that we're done. */
+ printf("DONE\n");
+
+ /* Hold memory until external kill signal is delivered. */
+ while (1)
+ sleep(100);
+ }
+
+ if (method == HUGETLBFS)
+ close(fd);
+
+ return 0;
+}