chmem: new tool

Move the s390 specific chmem tool to util-linux.

The chmem tool was originally written in perl and is part of the
s390-tools package which can be found here:
https://www.ibm.com/developerworks/linux/linux390/s390-tools.html

Given that the tool is architecture independent, there is no reason to
keep it in an s390 specific repository. It seems to be useful for
other architectures as well.

This patch converts the tool to C and adds it to util-linux, while the
command line options stay compatible. The only exception is the option
"-v" which used to be the short form of "--version". That got changed
to "-V" so it behaves like most other tools contained within
util-linux.

The chmem tool can be used to set memory online or offline. This can
be achieved by specifying a memory range:

Memory Block 19 (0x0000000130000000-0x000000013fffffff) disabled

or by specifying a size where chmem will automatically select memory
blocks:

Memory Block 21 (0x0000000150000000-0x000000015fffffff) disable failed
Memory Block 18 (0x0000000120000000-0x000000012fffffff) disabled
Memory Block 17 (0x0000000110000000-0x000000011fffffff) disabled
Memory Block 16 (0x0000000100000000-0x000000010fffffff) disabled
Memory Block 15 (0x00000000f0000000-0x00000000ffffffff) disabled

or by specifying memory block numbers instead of address ranges:

Memory Block 15 (0x00000000f0000000-0x00000000ffffffff) disabled
Memory Block 16 (0x0000000100000000-0x000000010fffffff) disabled
Memory Block 17 (0x0000000110000000-0x000000011fffffff) disabled
Memory Block 18 (0x0000000120000000-0x000000012fffffff) disabled

This is based on a patch from Clemens von Mann.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

1 files changed, 325 insertions, 0 deletions

diff --git a/sys-utils/chmem.c b/sys-utils/chmem.c
new file mode 100644
index 000000000..cc681b84c
--- /dev/null
+++ b/sys-utils/chmem.c
@@ -0,0 +1,325 @@
+/*
+ * chmem - Memory configuration tool
+ *
+ * Copyright IBM Corp. 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <assert.h>
+#include <dirent.h>
+
+#include <c.h>
+#include <nls.h>
+#include <path.h>
+#include <strutils.h>
+#include <strv.h>
+#include <optutils.h>
+#include <closestream.h>
+#include <xalloc.h>
+
+/* partial success, otherwise we return regular EXIT_{SUCCESS,FAILURE} */
+#define CHMEM_EXIT_SOMEOK		64
+
+#define _PATH_SYS_MEMORY		"/sys/devices/system/memory"
+#define _PATH_SYS_MEMORY_BLOCK_SIZE	_PATH_SYS_MEMORY "/block_size_bytes"
+
+struct chmem_desc {
+	struct dirent	**dirs;
+	int		ndirs;
+	uint64_t	block_size;
+	uint64_t	start;
+	uint64_t	end;
+	uint64_t	size;
+	unsigned int	use_blocks : 1;
+	unsigned int	is_size	   : 1;
+	unsigned int	verbose	   : 1;
+};
+
+enum {
+	CMD_MEMORY_ENABLE = 0,
+	CMD_MEMORY_DISABLE,
+	CMD_NONE
+};
+
+static void idxtostr(struct chmem_desc *desc, uint64_t idx, char *buf, size_t bufsz)
+{
+	uint64_t start, end;
+
+	start = idx * desc->block_size;
+	end = start + desc->block_size - 1;
+	snprintf(buf, bufsz,
+		 _("Memory Block %"SCNu64" (0x%016"PRIx64"-0x%016"PRIx64")"),
+		 idx, start, end);
+}
+
+static int chmem_size(struct chmem_desc *desc, int enable)
+{
+	char *name, *onoff, line[BUFSIZ], str[BUFSIZ];
+	uint64_t size, index;
+	int i, rc;
+
+	size = desc->size;
+	onoff = enable ? "online" : "offline";
+	i = enable ? 0 : desc->ndirs - 1;
+	for (; i >= 0 && i < desc->ndirs && size; i += enable ? 1 : -1) {
+		name = desc->dirs[i]->d_name;
+		index = strtou64_or_err(name + 6, _("Failed to parse index"));
+		path_read_str(line, sizeof(line), _PATH_SYS_MEMORY "/%s/state", name);
+		if (strcmp(onoff, line) == 0)
+			continue;
+		idxtostr(desc, index, str, sizeof(str));
+		rc = path_write_str(onoff, _PATH_SYS_MEMORY"/%s/state", name);
+		if (rc == -1 && desc->verbose) {
+			if (enable)
+				fprintf(stdout, _("%s enable failed\n"), str);
+			else
+				fprintf(stdout, _("%s disable failed\n"), str);
+		} else if (rc == 0 && desc->verbose) {
+			if (enable)
+				fprintf(stdout, _("%s enabled\n"), str);
+			else
+				fprintf(stdout, _("%s disabled\n"), str);
+		}
+		if (rc == 0)
+			size--;
+	}
+	if (size) {
+		uint64_t bytes;
+		char *sizestr;
+
+		bytes = (desc->size - size) * desc->block_size;
+		sizestr = size_to_human_string(SIZE_SUFFIX_1LETTER, bytes);
+		if (enable)
+			warnx(_("Could only enable %s of memory"), sizestr);
+		else
+			warnx(_("Could only disable %s of memory"), sizestr);
+		free(sizestr);
+	}
+	return size == 0 ? 0 : size == desc->size ? -1 : 1;
+}
+
+static int chmem_range(struct chmem_desc *desc, int enable)
+{
+	char *name, *onoff, line[BUFSIZ], str[BUFSIZ];
+	uint64_t index, todo;
+	int i, rc;
+
+	todo = desc->end - desc->start + 1;
+	onoff = enable ? "online" : "offline";
+	for (i = 0; i < desc->ndirs; i++) {
+		name = desc->dirs[i]->d_name;
+		index = strtou64_or_err(name + 6, _("Failed to parse index"));
+		if (index < desc->start)
+			continue;
+		if (index > desc->end)
+			break;
+		idxtostr(desc, index, str, sizeof(str));
+		path_read_str(line, sizeof(line), _PATH_SYS_MEMORY "/%s/state", name);
+		if (strcmp(onoff, line) == 0) {
+			if (desc->verbose && enable)
+				fprintf(stdout, _("%s already enabled\n"), str);
+			else if (desc->verbose && !enable)
+				fprintf(stdout, _("%s already disabled\n"), str);
+			todo--;
+			continue;
+		}
+		rc = path_write_str(onoff, _PATH_SYS_MEMORY"/%s/state", name);
+		if (rc == -1) {
+			if (enable)
+				warn(_("%s enable failed"), str);
+			else
+				warn(_("%s disable failed"), str);
+		} else if (desc->verbose) {
+			if (enable)
+				fprintf(stdout, _("%s enabled\n"), str);
+			else
+				fprintf(stdout, _("%s disabled\n"), str);
+		}
+		if (rc == 0)
+			todo--;
+	}
+	return todo == 0 ? 0 : todo == desc->end - desc->start + 1 ? -1 : 1;
+}
+
+static int filter(const struct dirent *de)
+{
+	if (strncmp("memory", de->d_name, 6))
+		return 0;
+	return isdigit_string(de->d_name + 6);
+}
+
+static void read_info(struct chmem_desc *desc)
+{
+	char line[BUFSIZ];
+
+	desc->ndirs = scandir(_PATH_SYS_MEMORY, &desc->dirs, filter, versionsort);
+	if (desc->ndirs <= 0)
+		err(EXIT_FAILURE, _("Failed to read %s"), _PATH_SYS_MEMORY);
+	path_read_str(line, sizeof(line), _PATH_SYS_MEMORY_BLOCK_SIZE);
+	desc->block_size = strtoumax(line, NULL, 16);
+}
+
+static void parse_single_param(struct chmem_desc *desc, char *str)
+{
+	if (desc->use_blocks) {
+		desc->start = strtou64_or_err(str, _("Failed to parse block number"));
+		desc->end = desc->start;
+		return;
+	}
+	desc->is_size = 1;
+	desc->size = strtosize_or_err(str, _("Failed to parse size"));
+	if (isdigit(str[strlen(str) - 1]))
+		desc->size *= 1024*1024;
+	if (desc->size % desc->block_size) {
+		errx(EXIT_FAILURE, _("Size must be aligned to memory block size (%s)"),
+		     size_to_human_string(SIZE_SUFFIX_1LETTER, desc->block_size));
+	}
+	desc->size /= desc->block_size;
+}
+
+static void parse_range_param(struct chmem_desc *desc, char *start, char *end)
+{
+	if (desc->use_blocks) {
+		desc->start = strtou64_or_err(start, _("Failed to parse start"));
+		desc->end = strtou64_or_err(end, _("Failed to parse end"));
+		return;
+	}
+	if (strlen(start) < 2 || start[1] != 'x')
+		errx(EXIT_FAILURE, _("Invalid start address format: %s"), start);
+	if (strlen(end) < 2 || end[1] != 'x')
+		errx(EXIT_FAILURE, _("Invalid end address format: %s"), end);
+	desc->start = strtox64_or_err(start, _("Failed to parse start address"));
+	desc->end = strtox64_or_err(end, _("Failed to parse end address"));
+	if (desc->start % desc->block_size || (desc->end + 1) % desc->block_size) {
+		errx(EXIT_FAILURE,
+		     _("Start address and (end address + 1) must be aligned to "
+		       "memory block size (%s)"),
+		     size_to_human_string(SIZE_SUFFIX_1LETTER, desc->block_size));
+	}
+	desc->start /= desc->block_size;
+	desc->end /= desc->block_size;
+}
+
+static void parse_parameter(struct chmem_desc *desc, char *param)
+{
+	char **split;
+
+	split = strv_split(param, "-");
+	if (strv_length(split) > 2)
+		errx(EXIT_FAILURE, _("Invalid parameter: %s"), param);
+	if (strv_length(split) == 1)
+		parse_single_param(desc, split[0]);
+	else
+		parse_range_param(desc, split[0], split[1]);
+	strv_free(split);
+	if (desc->start > desc->end)
+		errx(EXIT_FAILURE, _("Invalid range: %s"), param);
+}
+
+static void __attribute__((__noreturn__)) chmem_usage(FILE *out)
+{
+	fputs(USAGE_HEADER, out);
+	fprintf(out, _(" %s [options] [SIZE|RANGE|BLOCKRANGE]\n"), program_invocation_short_name);
+
+	fputs(USAGE_SEPARATOR, out);
+	fputs(_("Set a particular size or range of memory online or offline.\n"), out);
+
+	fputs(USAGE_OPTIONS, out);
+	fputs(_(" -e, --enable   enable memory\n"), out);
+	fputs(_(" -d, --disable  disable memory\n"), out);
+	fputs(_(" -b, --blocks   use memory blocks\n"), out);
+	fputs(_(" -v, --verbose  verbose output\n"), out);
+	fputs(USAGE_SEPARATOR, out);
+	fputs(USAGE_HELP, out);
+	fputs(USAGE_VERSION, out);
+
+	fprintf(out, USAGE_MAN_TAIL("chmem(8)"));
+
+	exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+
+int main(int argc, char **argv)
+{
+	struct chmem_desc _desc = { }, *desc = &_desc;
+	int cmd = CMD_NONE;
+	int c, rc;
+
+	static const struct option longopts[] = {
+		{"block",	no_argument,		NULL, 'b'},
+		{"disable",	no_argument,		NULL, 'd'},
+		{"enable",	no_argument,		NULL, 'e'},
+		{"help",	no_argument,		NULL, 'h'},
+		{"verbose",	no_argument,		NULL, 'v'},
+		{"version",	no_argument,		NULL, 'V'},
+		{NULL,		0,			NULL, 0}
+	};
+
+	static const ul_excl_t excl[] = {	/* rows and cols in ASCII order */
+		{ 'd','e' },
+		{ 0 }
+	};
+	int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+
+	setlocale(LC_ALL, "");
+	bindtextdomain(PACKAGE, LOCALEDIR);
+	textdomain(PACKAGE);
+	atexit(close_stdout);
+
+	read_info(desc);
+
+	while ((c = getopt_long(argc, argv, "bdehvV", longopts, NULL)) != -1) {
+
+		err_exclusive_options(c, longopts, excl, excl_st);
+
+		switch (c) {
+		case 'd':
+			cmd = CMD_MEMORY_DISABLE;
+			break;
+		case 'e':
+			cmd = CMD_MEMORY_ENABLE;
+			break;
+		case 'b':
+			desc->use_blocks = 1;
+			break;
+		case 'h':
+			chmem_usage(stdout);
+			break;
+		case 'v':
+			desc->verbose = 1;
+			break;
+		case 'V':
+			printf(UTIL_LINUX_VERSION);
+			return EXIT_SUCCESS;
+		}
+	}
+
+	if ((argc == 1) || (argc != optind + 1) || (cmd == CMD_NONE))
+		chmem_usage(stderr);
+
+	parse_parameter(desc, argv[optind]);
+
+	if (desc->is_size)
+		rc = chmem_size(desc, cmd == CMD_MEMORY_ENABLE ? 1 : 0);
+	else
+		rc = chmem_range(desc, cmd == CMD_MEMORY_ENABLE ? 1 : 0);
+
+	return rc == 0 ? EXIT_SUCCESS :
+		rc < 0 ? EXIT_FAILURE : CHMEM_EXIT_SOMEOK;
+}