Merge "Workaround perdev_minors path change in Linux"

Disk.cpp

@@ -49,7 +49,8 @@ static const char* kSgdiskPath = "/system/bin/sgdisk";
 static const char* kSgdiskToken = " \t\n";
 
 static const char* kSysfsLoopMaxMinors = "/sys/module/loop/parameters/max_part";
-static const char* kSysfsMmcMaxMinors = "/sys/module/mmcblk/parameters/perdev_minors";
+static const char* kSysfsMmcMaxMinorsDeprecated = "/sys/module/mmcblk/parameters/perdev_minors";
+static const char* kSysfsMmcMaxMinors = "/sys/module/mmc_block/parameters/perdev_minors";
 
 static const unsigned int kMajorBlockLoop = 7;
 static const unsigned int kMajorBlockScsiA = 8;
@@ -559,7 +560,8 @@ int Disk::getMaxMinors() {
     case kMajorBlockMmc: {
         // Per Documentation/devices.txt this is dynamic
         std::string tmp;
-        if (!ReadFileToString(kSysfsMmcMaxMinors, &tmp)) {
+        if (!ReadFileToString(kSysfsMmcMaxMinors, &tmp) &&
+                !ReadFileToString(kSysfsMmcMaxMinorsDeprecated, &tmp)) {
             LOG(ERROR) << "Failed to read max minors";
             return -errno;
         }