From adce35320f00f09f4c1e5f0303a771ec205a20fd Mon Sep 17 00:00:00 2001
From: kib <kib@FreeBSD.org>
Date: Wed, 9 Sep 2020 22:22:02 +0000
Subject: [PATCH] Add posixshmcontrol(1) support for largepage shm objects.

Create op with -l <largepage> option can create it, stat displays
configured page size.

Reviewed by:	markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D24652
---
 usr.bin/posixshmcontrol/posixshmcontrol.c | 74 ++++++++++++++++++++---
 1 file changed, 64 insertions(+), 10 deletions(-)

diff --git a/usr.bin/posixshmcontrol/posixshmcontrol.c b/usr.bin/posixshmcontrol/posixshmcontrol.c
index 5bf037088b41..3ebb722ae4fb 100644
--- a/usr.bin/posixshmcontrol/posixshmcontrol.c
+++ b/usr.bin/posixshmcontrol/posixshmcontrol.c
@@ -30,8 +30,10 @@
 __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
+#include <sys/filio.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
+#include <sys/syscall.h>
 #include <sys/sysctl.h>
 #include <sys/user.h>
 #include <err.h>
@@ -50,7 +52,7 @@ usage(void)
 {
 
 	fprintf(stderr, "Usage:\n"
-	    "posixshmcontrol create [-m <mode>] <path> ...\n"
+	    "posixshmcontrol create [-m <mode>] [-l <largepage>] <path> ...\n"
 	    "posixshmcontrol rm <path> ...\n"
 	    "posixshmcontrol ls [-h] [-n]\n"
 	    "posixshmcontrol dump <path> ...\n"
@@ -59,14 +61,23 @@ usage(void)
 }
 
 static int
-create_one_shm(const char *path, long mode)
+create_one_shm(const char *path, long mode, int idx)
 {
 	int fd;
 
-	fd = shm_open(path, O_RDWR | O_CREAT, mode);
-	if (fd == -1) {
-		warn("create %s", path);
-		return (1);
+	if (idx == -1) {
+		fd = shm_open(path, O_RDWR | O_CREAT, mode);
+		if (fd == -1) {
+			warn("create %s", path);
+			return (1);
+		}
+	} else {
+		fd = shm_create_largepage(path, O_RDWR, idx,
+		    SHM_LARGEPAGE_ALLOC_DEFAULT, mode);
+		if (fd == -1) {
+			warn("shm_create_largepage %s psind %d", path, idx);
+			return (1);
+		}
 	}
 	close(fd);
 	return (0);
@@ -76,20 +87,60 @@ static int
 create_shm(int argc, char **argv)
 {
 	char *end;
+	size_t *pagesizes;
 	long mode;
-	int c, i, ret, ret1;
+	uint64_t pgsz;
+	int c, i, idx, pn, ret, ret1;
+	bool printed;
 
 	mode = 0600;
-	while ((c = getopt(argc, argv, "m:")) != -1) {
+	idx = -1;
+	while ((c = getopt(argc, argv, "l:m:")) != -1) {
 		switch (c) {
 		case 'm':
 			errno = 0;
 			mode = strtol(optarg, &end, 0);
 			if (mode == 0 && errno != 0)
-				err(1, "mode:");
+				err(1, "mode");
 			if (*end != '\0')
 				errx(1, "non-integer mode");
 			break;
+		case 'l':
+			if (expand_number(optarg, &pgsz) == -1)
+				err(1, "size");
+			pn = getpagesizes(NULL, 0);
+			if (pn == -1)
+				err(1, "getpagesizes");
+			pagesizes = malloc(sizeof(size_t) * pn);
+			if (pagesizes == NULL)
+				err(1, "malloc");
+			if (getpagesizes(pagesizes, pn) == -1)
+				err(1, "gtpagesizes");
+			for (idx = 0; idx < pn; idx++) {
+				if (pagesizes[idx] == pgsz)
+					break;
+			}
+			if (idx == pn) {
+				fprintf(stderr,
+    "pagesize should be superpagesize, supported sizes:");
+				printed = false;
+				for (i = 0; i < pn; i++) {
+					if (pagesizes[i] == 0 ||
+					    pagesizes[i] == (size_t)
+					    getpagesize())
+						continue;
+					printed = true;
+					fprintf(stderr, " %zu", pagesizes[i]);
+				}
+				if (!printed)
+					fprintf(stderr, " none");
+				fprintf(stderr, "\n");
+				exit(1);
+			}
+			if (pgsz == (uint64_t)getpagesize())
+				errx(1, "pagesize should be large");
+			free(pagesizes);
+			break;
 		case '?':
 		default:
 			usage();
@@ -101,7 +152,7 @@ create_shm(int argc, char **argv)
 	argv += optind;
 	ret = 0;
 	for (i = 0; i < argc; i++) {
-		ret1 = create_one_shm(argv[i], mode);
+		ret1 = create_one_shm(argv[i], mode, idx);
 		if (ret1 != 0 && ret == 0)
 			ret = ret1;
 	}
@@ -349,6 +400,9 @@ stat_one_shm(const char *path, bool hsize, bool uname)
 		    (long)st.st_ctim.tv_nsec);
 		printf("birth\t%ld.%09ld\n", (long)st.st_birthtim.tv_sec,
 		    (long)st.st_birthtim.tv_nsec);
+		if (st.st_blocks != 0)
+			printf("pagesz\t%jd\n", roundup((uintmax_t)st.st_size,
+			    PAGE_SIZE) / st.st_blocks);
 	}
 	close(fd);
 	return (ret);