Merge "Workaround perdev_minors path change in Linux"

am: d3870c5167

Change-Id: Ia7ec03a566f8c122dff05bcc3d996c05cf2b7771

Disk.cpp

@@ -50,7 +50,8 @@ 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;
@@ -566,7 +567,8 @@ 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;
         }