Close /dev/mem file descriptor when not needed anymore

Signed-off-by: Andi Kleen <ak@linux.intel.com>

dmi.c

@@ -55,6 +55,7 @@ struct anchor {
 } __attribute__((packed));
 
 static struct dmi_entry *entries;
+static int entrieslen;
 static int numentries;
 static int dmi_length;
 static struct dmi_entry **handle_to_entry;
@@ -175,7 +176,8 @@ int opendmi(void)
 		printf("DMI tables at %x, %u bytes, %u entries\n", 
 			a->table, a->length, a->numentries);
 	corr = a->table - round_down(a->table, pagesize); 
- 	entries = mmap(NULL, round_up(a->length + pagesize, pagesize), 
+	entrieslen = round_up(a->length + pagesize, pagesize);
+ 	entries = mmap(NULL, entrieslen, 
 		       	PROT_READ, MAP_SHARED, memfd, 
 			round_down(a->table, pagesize));
 	if (entries == (struct dmi_entry *)-1) { 
@@ -526,3 +528,18 @@ void checkdmi(void)
 	if (!dmi_forced)
 		do_dmi = dmi_sanity_check();
 }
+
+#define FREE(x) free(x), (x) = NULL
+
+void closedmi(void)
+{
+	if (!entries) 
+		return;
+	munmap(entries, entrieslen);
+	entries = NULL;
+	FREE(dmi_dimms);
+	FREE(dmi_arrays);
+	FREE(dmi_ranges);
+	FREE(dmi_array_ranges);
+	FREE(handle_to_entry);
+}

dmi.h

@@ -70,6 +70,7 @@ void dmi_set_verbosity(int v);
 
 char *dmi_getstring(struct dmi_entry *e, unsigned number);
 extern void checkdmi(void);
+void closedmi(void);
 
 /* valid after opendmi: */
 extern struct dmi_memdev **dmi_dimms; 

mcelog.c

@@ -1032,6 +1032,8 @@ int main(int ac, char **av)
 	if (daemon_mode) {
 		check_cpu();
 		prefill_memdb();
+		if (!do_dmi)
+			closedmi();
 		server_setup();
 		page_setup();
 		drop_cred();