Initial s390-tools-2.0.0 import

This commit is based on the s390-tools-1.39.0 version.

Changes on top of s390-tools-1.39.0:

 - Add MIT license to all source files
 - Add LICENSE file
 - Transform REAMDE to README.md (markdown)
 - Add AUTHORS.md file
 - Add CONTRIBUTING.md file
 - Move changelog from README to CHANGELOG.md file

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>

zdump/dfi_devmem.c

@@ -0,0 +1,158 @@
+/*
+ * zgetdump - Tool for copying and converting System z dumps
+ *
+ * /dev/mem and /dev/crash dump input format
+ *
+ * Copyright IBM Corp. 2012, 2017
+ *
+ * s390-tools is free software; you can redistribute it and/or modify
+ * it under the terms of the MIT license. See LICENSE for details.
+ */
+
+#include <fcntl.h>
+#include <limits.h>
+#include <linux/fs.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/utsname.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "zgetdump.h"
+
+/*
+ * Add live dump magic to buffer
+ */
+static void add_live_magic(void *buf, u64 off, u64 cnt)
+{
+	if (off >= sizeof(dfi_live_dump_magic))
+		return;
+	memcpy(buf, &dfi_live_dump_magic,
+	       MIN(cnt, sizeof(dfi_live_dump_magic)));
+}
+
+/*
+ * "devmem" mem chunk read callback
+ *
+ * This functions reads page wise in order to detect unreadable pages
+ */
+static void dfi_devmem_mem_chunk_read(struct dfi_mem_chunk *mem_chunk, u64 off,
+				      void *buf, u64 cnt)
+{
+	u64 copied = 0, len = PAGE_SIZE;
+	(void) mem_chunk;
+
+	if (off % PAGE_SIZE)
+		len = MIN(len, PAGE_SIZE - off % PAGE_SIZE);
+	len = MIN(len, cnt);
+	do {
+		zg_seek(g.fh, mem_chunk->start + off + copied, ZG_CHECK);
+		if (zg_read(g.fh, buf + copied, len, ZG_CHECK_NONE) < 0) {
+			if (errno == EFAULT) {
+				/* This can happen when using CMM */
+				memset(buf + copied, 0, len);
+			} else {
+				ERR_EXIT_ERRNO("Could not read %s",
+					       g.opts.device);
+			}
+		}
+		copied += len;
+		len = MIN(PAGE_SIZE, cnt - copied);
+	} while (len);
+	add_live_magic(buf, mem_chunk->start + off, cnt);
+}
+
+/*
+ * Detect memory chunks via /proc/iomem
+ *
+ * check = 0: Initialize memory map
+ * check = 1: Verifiy that current system memory map is same as DFI memory map
+ */
+static int detect_mem_chunks(int check)
+{
+	char line[4096], type1[4096], type2[4096];
+	unsigned long start, end, cnt = 0;
+	struct dfi_mem_chunk *mem_chunk;
+	struct zg_fh *fh;
+	ssize_t rc;
+
+	fh = zg_open("/proc/iomem", O_RDONLY, ZG_CHECK);
+	do {
+		rc = zg_gets(fh, line, sizeof(line), ZG_CHECK);
+		if (rc == 0)
+			break;
+		sscanf(line, "%lx-%lx : %s %s", &start, &end, type1, type2);
+		if (strcmp(type1, "System") != 0)
+			continue;
+		if (strcmp(type2, "RAM") != 0 && strcmp(type2, "ROM") != 0)
+			continue;
+		if (check) {
+			mem_chunk = dfi_mem_chunk_find(start);
+			if (!mem_chunk)
+				return -EINVAL;
+			if (mem_chunk->start != start)
+				return -EINVAL;
+			if (mem_chunk->end != end)
+				return -EINVAL;
+			cnt++;
+		} else {
+			dfi_mem_chunk_add(start, end - start + 1, NULL,
+					  dfi_devmem_mem_chunk_read, NULL);
+		}
+	} while (1);
+	if (check && cnt != dfi_mem_chunk_cnt())
+		return -EINVAL;
+	return 0;
+}
+
+/*
+ * Return architecture of running system
+ */
+static enum dfi_arch system_arch(void)
+{
+	struct utsname utsname;
+
+	uname(&utsname);
+	if (memcmp(utsname.machine, "s390x", 5) == 0)
+		return DFI_ARCH_64;
+	if (memcmp(utsname.machine, "s390", 4) == 0)
+		return DFI_ARCH_32;
+	return DFI_ARCH_UNKNOWN;
+}
+
+/*
+ * Initialize devmem DFI
+ */
+static int dfi_devmem_init(void)
+{
+	if (strcmp(g.fh->path, "/dev/mem") != 0 &&
+	    strcmp(g.fh->path, "/dev/crash") != 0)
+		return -ENODEV;
+	dfi_arch_set(system_arch());
+	dfi_cpu_info_init(DFI_CPU_CONTENT_NONE);
+	detect_mem_chunks(0);
+	dfi_attr_dump_method_set(DFI_DUMP_METHOD_LIVE);
+	zg_seek(g.fh, 0, ZG_CHECK);
+	return 0;
+}
+
+/*
+ * Cleanup devmem DFI
+ */
+static void dfi_devmem_exit(void)
+{
+	if (detect_mem_chunks(1))
+		STDERR("Warning: memory map has changed\n");
+}
+
+/*
+ * devmem DFI operations
+ */
+struct dfi dfi_devmem = {
+	.name		= "devmem",
+	.init		= dfi_devmem_init,
+	.exit		= dfi_devmem_exit,
+	.feat_bits	= DFI_FEAT_COPY | DFI_FEAT_SEEK,
+};