xpmem: support large page

1. try to use as large page as possible on attach
2. pre-map resident remote pages on attach

Change-Id: I5580682a4199e94085a9bad9ce3958a0f14cdcea

test/issues/1473/xpmem_attach01.c

@@ -0,0 +1,143 @@
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/wait.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <libgen.h>
+#include <xpmem.h>
+#include "okng.h"
+#include "util.h"
+
+#define DEBUG
+
+#define MAP_HUGE_SHIFT 26
+#define MAGIC_HEAD 0x12345678UL
+#define MAGIC_TAIL 0x9abcdef0UL
+
+int main(int argc, char **argv)
+{
+	int i;
+	void *mem;
+	int ret;
+	pid_t pid;
+	int status;
+	xpmem_segid_t segid;
+	int att_pgshift, seg_pgshift;
+	size_t att_pgsize, seg_pgsize;
+
+	if (argc < 3) {
+		printf("Err: Too few arguments\n");
+		printf("Usage: %s <seg_pgshift> <att_pgshift>\n",
+		       basename(argv[0]));
+		printf("\tpgshift : page-shift of attachment\n");
+		printf("\tpgshift : page-shift of segment\n");
+		return 1;
+	}
+
+	seg_pgshift = atoi(argv[1]);
+	seg_pgsize = (1UL << seg_pgshift);
+	att_pgshift = atoi(argv[2]);
+	att_pgsize = (1UL << att_pgshift);
+
+	INTERR(seg_pgsize > att_pgsize,
+	       "seg_pgsize (%lx) > att_pgsize (%lx)\n",
+	       seg_pgsize, att_pgsize);
+
+	printf("parent: seg_pgsize: 0x%lx\n", seg_pgsize);
+	printf("parent: att_pgsize: 0x%lx\n", att_pgsize);
+
+	mem = mmap(0, att_pgsize,
+		   PROT_READ | PROT_WRITE,
+		   MAP_ANONYMOUS | MAP_PRIVATE |
+		   MAP_HUGETLB | (att_pgshift << MAP_HUGE_SHIFT),
+		   -1, 0);
+
+	INTERR(mem == MAP_FAILED, "mapping att_pgsize memory failed\n");
+	printf("parent: anonymous_map_addr: %lx - %lx\n",
+	       (unsigned long)mem,
+	       (unsigned long)mem + att_pgsize);
+
+	/* Create physically-contiguous maps with smaller page-size */
+	for (i = 0; i < att_pgsize / seg_pgsize; i++) {
+		void *smaller;
+		void *addr = mem + i * seg_pgsize;
+
+		smaller = mmap(addr, seg_pgsize,
+			   PROT_READ | PROT_WRITE,
+			   MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED,
+			   -1, 0);
+		INTERR(smaller == MAP_FAILED,
+		       "mapping seg_pgsize memory failed\n");
+
+		/* to distinguish from the large page at mem */
+		if (i == 1) {
+			printf("parent: seg_addr: %lx\n",
+			       (unsigned long)addr);
+		}
+	}
+
+	segid = xpmem_make((void *)mem,
+			   att_pgsize, XPMEM_PERMIT_MODE, (void *)0666);
+	INTERR(segid == -1, "xpmem_make: addr: %lx, size: %lx, error: %s\n",
+	       (unsigned long)mem, att_pgsize, strerror(errno));
+
+	fflush(stdout); /* to prevent buffer from getting duplicated */
+
+	pid = fork();
+	INTERR(pid == -1, "fork failed\n");
+
+	if (pid == 0) {
+		xpmem_apid_t apid;
+		struct xpmem_addr addr;
+		void *attach;
+
+		apid = xpmem_get(segid, XPMEM_RDWR,
+				 XPMEM_PERMIT_MODE, NULL);
+		OKNG(apid != -1, "apid: %lx\n", (unsigned long)apid);
+
+		addr.apid = apid;
+		addr.offset = 0;
+
+		INFO("child: attaching...\n");
+		attach = xpmem_attach(addr, att_pgsize, NULL);
+		INTERR(attach == (void *)-1,
+		       "xpmem_attach: size: %lx, error: %s\n",
+		     att_pgsize, strerror(errno));
+
+		printf("child: att_addr: %lx\n", (unsigned long)attach);
+
+		*((unsigned long *)attach) = MAGIC_HEAD;
+		*((unsigned long *)(attach + att_pgsize
+				    - sizeof(unsigned long *))) = MAGIC_TAIL;
+
+		ret = xpmem_detach(attach);
+		INTERR(ret == -1, "xpmem_detach failed\n");
+
+		exit(0);
+	} else {
+		INFO("parent: waiting...\n");
+		ret = waitpid(pid, &status, 0);
+		INFO("parent: children found\n");
+		INTERR(ret == -1, "waitpid failed\n");
+
+		OKNG(*(unsigned long *)mem == MAGIC_HEAD,
+		     "HEAD of xpmem area is shared\n");
+		OKNG(*((unsigned long *)(mem + att_pgsize
+					 - sizeof(unsigned long *))) ==
+		     MAGIC_TAIL, "TAIL of xpmem area is shared\n");
+
+		ret = xpmem_remove(segid);
+		INTERR(ret == -1, "xpmem_remove failed\n");
+	}
+
+	ret = 0;
+ out:
+	return ret;
+}