1 files changed, 166 insertions, 0 deletions
diff --git a/kernel/kexec.c b/kernel/kexec.c
index fbffdb4..aa74a1e 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1146,6 +1146,172 @@ static int __init crash_notes_memory_init(void)
 }
 module_init(crash_notes_memory_init)
 
+
+/*
+ * parsing the "crashkernel" commandline
+ *
+ * this code is intended to be called from architecture specific code
+ */
+
+
+/*
+ * This function parses command lines in the format
+ *
+ *   crashkernel=ramsize-range:size[,...][@offset]
+ *
+ * The function returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_mem(char 			*cmdline,
+					unsigned long long	system_ram,
+					unsigned long long	*crash_size,
+					unsigned long long	*crash_base)
+{
+	char *cur = cmdline, *tmp;
+
+	/* for each entry of the comma-separated list */
+	do {
+		unsigned long long start, end = ULLONG_MAX, size;
+
+		/* get the start of the range */
+		start = memparse(cur, &tmp);
+		if (cur == tmp) {
+			pr_warning("crashkernel: Memory value expected\n");
+			return -EINVAL;
+		}
+		cur = tmp;
+		if (*cur != '-') {
+			pr_warning("crashkernel: '-' expected\n");
+			return -EINVAL;
+		}
+		cur++;
+
+		/* if no ':' is here, than we read the end */
+		if (*cur != ':') {
+			end = memparse(cur, &tmp);
+			if (cur == tmp) {
+				pr_warning("crashkernel: Memory "
+						"value expected\n");
+				return -EINVAL;
+			}
+			cur = tmp;
+			if (end <= start) {
+				pr_warning("crashkernel: end <= start\n");
+				return -EINVAL;
+			}
+		}
+
+		if (*cur != ':') {
+			pr_warning("crashkernel: ':' expected\n");
+			return -EINVAL;
+		}
+		cur++;
+
+		size = memparse(cur, &tmp);
+		if (cur == tmp) {
+			pr_warning("Memory value expected\n");
+			return -EINVAL;
+		}
+		cur = tmp;
+		if (size >= system_ram) {
+			pr_warning("crashkernel: invalid size\n");
+			return -EINVAL;
+		}
+
+		/* match ? */
+		if (system_ram >= start && system_ram <= end) {
+			*crash_size = size;
+			break;
+		}
+	} while (*cur++ == ',');
+
+	if (*crash_size > 0) {
+		while (*cur != ' ' && *cur != '@')
+			cur++;
+		if (*cur == '@') {
+			cur++;
+			*crash_base = memparse(cur, &tmp);
+			if (cur == tmp) {
+				pr_warning("Memory value expected "
+						"after '@'\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * That function parses "simple" (old) crashkernel command lines like
+ *
+ * 	crashkernel=size[@offset]
+ *
+ * It returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_simple(char 		*cmdline,
+					   unsigned long long 	*crash_size,
+					   unsigned long long 	*crash_base)
+{
+	char *cur = cmdline;
+
+	*crash_size = memparse(cmdline, &cur);
+	if (cmdline == cur) {
+		pr_warning("crashkernel: memory value expected\n");
+		return -EINVAL;
+	}
+
+	if (*cur == '@')
+		*crash_base = memparse(cur+1, &cur);
+
+	return 0;
+}
+
+/*
+ * That function is the entry point for command line parsing and should be
+ * called from the arch-specific code.
+ */
+int __init parse_crashkernel(char 		 *cmdline,
+			     unsigned long long system_ram,
+			     unsigned long long *crash_size,
+			     unsigned long long *crash_base)
+{
+	char 	*p = cmdline, *ck_cmdline = NULL;
+	char	*first_colon, *first_space;
+
+	BUG_ON(!crash_size || !crash_base);
+	*crash_size = 0;
+	*crash_base = 0;
+
+	/* find crashkernel and use the last one if there are more */
+	p = strstr(p, "crashkernel=");
+	while (p) {
+		ck_cmdline = p;
+		p = strstr(p+1, "crashkernel=");
+	}
+
+	if (!ck_cmdline)
+		return -EINVAL;
+
+	ck_cmdline += 12; /* strlen("crashkernel=") */
+
+	/*
+	 * if the commandline contains a ':', then that's the extended
+	 * syntax -- if not, it must be the classic syntax
+	 */
+	first_colon = strchr(ck_cmdline, ':');
+	first_space = strchr(ck_cmdline, ' ');
+	if (first_colon && (!first_space || first_colon < first_space))
+		return parse_crashkernel_mem(ck_cmdline, system_ram,
+				crash_size, crash_base);
+	else
+		return parse_crashkernel_simple(ck_cmdline, crash_size,
+				crash_base);
+
+	return 0;
+}
+
+
+
 void crash_save_vmcoreinfo(void)
 {
 	u32 *buf;