delay accessing misc partition until its device exists
When the misc partition is on an emmc device, recovery can get started
and try to access it before the kernel has actually created the
device. Try statting the device before reading or writing it; delay
up to 10 seconds waiting for the device to exist.
Change-Id: I93256db4b047c76020490e8a3dc76b8ade643291
diff --git a/bootloader.c b/bootloader.c
index b690c55..7096566 100644
--- a/bootloader.c
+++ b/bootloader.c
@@ -22,6 +22,8 @@
#include <errno.h>
#include <stdio.h>
#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
static int get_bootloader_message_mtd(struct bootloader_message *out, const Volume* v);
static int set_bootloader_message_mtd(const struct bootloader_message *in, const Volume* v);
@@ -132,8 +134,26 @@
// for misc partitions on block devices
// ------------------------------------
+static void wait_for_device(const char* fn) {
+ int tries = 0;
+ int ret;
+ struct stat buf;
+ do {
+ ++tries;
+ ret = stat(fn, &buf);
+ if (ret) {
+ printf("stat %s try %d: %s\n", fn, tries, strerror(errno));
+ sleep(1);
+ }
+ } while (ret && tries < 10);
+ if (ret) {
+ printf("failed to stat %s\n", fn);
+ }
+}
+
static int get_bootloader_message_block(struct bootloader_message *out,
const Volume* v) {
+ wait_for_device(v->device);
FILE* f = fopen(v->device, "rb");
if (f == NULL) {
LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno));
@@ -155,6 +175,7 @@
static int set_bootloader_message_block(const struct bootloader_message *in,
const Volume* v) {
+ wait_for_device(v->device);
FILE* f = fopen(v->device, "wb");
if (f == NULL) {
LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno));