Volume.cpp - SHIFTPHONES/android_system_vold - Gitiles

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <stdlib.h>
 #include <string.h>
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/mman.h>
 #include <sys/mount.h>

 #include <linux/kdev_t.h>
 #include <linux/fs.h>

 #include <cutils/properties.h>

 #include <diskconfig/diskconfig.h>

 #define LOG_TAG "Vold"

 #include <cutils/log.h>

 #include "Volume.h"
 #include "VolumeManager.h"
 #include "ResponseCode.h"
 #include "Fat.h"
 #include "Process.h"

 extern "C" void dos_partition_dec(void const *pp, struct dos_partition *d);
 extern "C" void dos_partition_enc(void *pp, struct dos_partition *d);


 /*
  * Secure directory - stuff that only root can see
  */
 const char *Volume::SECDIR            = "/mnt/secure";

 /*
  * Secure staging directory - where media is mounted for preparation
  */
 const char *Volume::SEC_STGDIR        = "/mnt/secure/staging";

 /*
  * Path to the directory on the media which contains publicly accessable
  * asec imagefiles. This path will be obscured before the mount is
  * exposed to non priviledged users.
  */
 const char *Volume::SEC_STG_SECIMGDIR = "/mnt/secure/staging/.android_secure";

 /*
  * Path to where *only* root can access asec imagefiles
  */
 const char *Volume::SEC_ASECDIR       = "/mnt/secure/asec";

 /*
  * Path to where secure containers are mounted
  */
 const char *Volume::ASECDIR           = "/mnt/asec";

 /*
  * Path to where OBBs are mounted
  */
 const char *Volume::LOOPDIR           = "/mnt/obb";

 static const char *stateToStr(int state) {
     if (state == Volume::State_Init)
         return "Initializing";
     else if (state == Volume::State_NoMedia)
         return "No-Media";
     else if (state == Volume::State_Idle)
         return "Idle-Unmounted";
     else if (state == Volume::State_Pending)
         return "Pending";
     else if (state == Volume::State_Mounted)
         return "Mounted";
     else if (state == Volume::State_Unmounting)
         return "Unmounting";
     else if (state == Volume::State_Checking)
         return "Checking";
     else if (state == Volume::State_Formatting)
         return "Formatting";
     else if (state == Volume::State_Shared)
         return "Shared-Unmounted";
     else if (state == Volume::State_SharedMnt)
         return "Shared-Mounted";
     else
         return "Unknown-Error";
 }

 Volume::Volume(VolumeManager *vm, const char *label, const char *mount_point) {
     mVm = vm;
     mDebug = false;
     mLabel = strdup(label);
     mMountpoint = strdup(mount_point);
     mState = Volume::State_Init;
     mCurrentlyMountedKdev = -1;
     mPartIdx = -1;
 }

 Volume::~Volume() {
     free(mLabel);
     free(mMountpoint);
 }

 void Volume::protectFromAutorunStupidity() {
     char filename[255];

     snprintf(filename, sizeof(filename), "%s/autorun.inf", SEC_STGDIR);
     if (!access(filename, F_OK)) {
         SLOGW("Volume contains an autorun.inf! - removing");
         /*
          * Ensure the filename is all lower-case so
          * the process killer can find the inode.
          * Probably being paranoid here but meh.
          */
         rename(filename, filename);
         Process::killProcessesWithOpenFiles(filename, 2);
         if (unlink(filename)) {
             SLOGE("Failed to remove %s (%s)", filename, strerror(errno));
         }
     }
 }

 void Volume::setDebug(bool enable) {
     mDebug = enable;
 }

 dev_t Volume::getDiskDevice() {
     return MKDEV(0, 0);
 };

 dev_t Volume::getShareDevice() {
     return getDiskDevice();
 }

 void Volume::handleVolumeShared() {
 }

 void Volume::handleVolumeUnshared() {
 }

 int Volume::handleBlockEvent(NetlinkEvent *evt) {
     errno = ENOSYS;
     return -1;
 }

 void Volume::setState(int state) {
     char msg[255];
     int oldState = mState;

     if (oldState == state) {
         SLOGW("Duplicate state (%d)\n", state);
         return;
     }

     mState = state;

     SLOGD("Volume %s state changing %d (%s) -> %d (%s)", mLabel,
          oldState, stateToStr(oldState), mState, stateToStr(mState));
     snprintf(msg, sizeof(msg),
              "Volume %s %s state changed from %d (%s) to %d (%s)", getLabel(),
              getMountpoint(), oldState, stateToStr(oldState), mState,
              stateToStr(mState));

     mVm->getBroadcaster()->sendBroadcast(ResponseCode::VolumeStateChange,
                                          msg, false);
 }

 int Volume::createDeviceNode(const char *path, int major, int minor) {
     mode_t mode = 0660 | S_IFBLK;
     dev_t dev = (major << 8) | minor;
     if (mknod(path, mode, dev) < 0) {
         if (errno != EEXIST) {
             return -1;
         }
     }
     return 0;
 }

 int Volume::formatVol() {

     if (getState() == Volume::State_NoMedia) {
         errno = ENODEV;
         return -1;
     } else if (getState() != Volume::State_Idle) {
         errno = EBUSY;
         return -1;
     }

     if (isMountpointMounted(getMountpoint())) {
         SLOGW("Volume is idle but appears to be mounted - fixing");
         setState(Volume::State_Mounted);
         // mCurrentlyMountedKdev = XXX
         errno = EBUSY;
         return -1;
     }

     bool formatEntireDevice = (mPartIdx == -1);
     char devicePath[255];
     dev_t diskNode = getDiskDevice();
     dev_t partNode = MKDEV(MAJOR(diskNode), (formatEntireDevice ? 1 : mPartIdx));

     setState(Volume::State_Formatting);

     int ret = -1;
     // Only initialize the MBR if we are formatting the entire device
     if (formatEntireDevice) {
         sprintf(devicePath, "/dev/block/vold/%d:%d",
                 MAJOR(diskNode), MINOR(diskNode));

         if (initializeMbr(devicePath)) {
             SLOGE("Failed to initialize MBR (%s)", strerror(errno));
             goto err;
         }
     }

     sprintf(devicePath, "/dev/block/vold/%d:%d",
             MAJOR(partNode), MINOR(partNode));

     if (mDebug) {
         SLOGI("Formatting volume %s (%s)", getLabel(), devicePath);
     }

     if (Fat::format(devicePath, 0)) {
         SLOGE("Failed to format (%s)", strerror(errno));
         goto err;
     }

     ret = 0;

 err:
     setState(Volume::State_Idle);
     return ret;
 }

 bool Volume::isMountpointMounted(const char *path) {
     char device[256];
     char mount_path[256];
     char rest[256];
     FILE *fp;
     char line[1024];

     if (!(fp = fopen("/proc/mounts", "r"))) {
         SLOGE("Error opening /proc/mounts (%s)", strerror(errno));
         return false;
     }

     while(fgets(line, sizeof(line), fp)) {
         line[strlen(line)-1] = '\0';
         sscanf(line, "%255s %255s %255s\n", device, mount_path, rest);
         if (!strcmp(mount_path, path)) {
             fclose(fp);
             return true;
         }

     }

     fclose(fp);
     return false;
 }

 int Volume::mountVol() {
     dev_t deviceNodes[4];
     int n, i, rc = 0;
     char errmsg[255];

     if (getState() == Volume::State_NoMedia) {
         snprintf(errmsg, sizeof(errmsg),
                  "Volume %s %s mount failed - no media",
                  getLabel(), getMountpoint());
         mVm->getBroadcaster()->sendBroadcast(
                                          ResponseCode::VolumeMountFailedNoMedia,
                                          errmsg, false);
         errno = ENODEV;
         return -1;
     } else if (getState() != Volume::State_Idle) {
         errno = EBUSY;
         return -1;
     }

     if (isMountpointMounted(getMountpoint())) {
         SLOGW("Volume is idle but appears to be mounted - fixing");
         setState(Volume::State_Mounted);
         // mCurrentlyMountedKdev = XXX
         return 0;
     }

     n = getDeviceNodes((dev_t *) &deviceNodes, 4);
     if (!n) {
         SLOGE("Failed to get device nodes (%s)\n", strerror(errno));
         return -1;
     }

     for (i = 0; i < n; i++) {
         char devicePath[255];

         sprintf(devicePath, "/dev/block/vold/%d:%d", MAJOR(deviceNodes[i]),
                 MINOR(deviceNodes[i]));

         SLOGI("%s being considered for volume %s\n", devicePath, getLabel());

         errno = 0;
         setState(Volume::State_Checking);

         if (Fat::check(devicePath)) {
             if (errno == ENODATA) {
                 SLOGW("%s does not contain a FAT filesystem\n", devicePath);
                 continue;
             }
             errno = EIO;
             /* Badness - abort the mount */
             SLOGE("%s failed FS checks (%s)", devicePath, strerror(errno));
             setState(Volume::State_Idle);
             return -1;
         }

         /*
          * Mount the device on our internal staging mountpoint so we can
          * muck with it before exposing it to non priviledged users.
          */
         errno = 0;
         if (Fat::doMount(devicePath, "/mnt/secure/staging", false, false, false,
                 1000, 1015, 0702, true)) {
             SLOGE("%s failed to mount via VFAT (%s)\n", devicePath, strerror(errno));
             continue;
         }

         SLOGI("Device %s, target %s mounted @ /mnt/secure/staging", devicePath, getMountpoint());

         protectFromAutorunStupidity();

         if (createBindMounts()) {
             SLOGE("Failed to create bindmounts (%s)", strerror(errno));
             umount("/mnt/secure/staging");
             setState(Volume::State_Idle);
             return -1;
         }

         /*
          * Now that the bindmount trickery is done, atomically move the
          * whole subtree to expose it to non priviledged users.
          */
         if (doMoveMount("/mnt/secure/staging", getMountpoint(), false)) {
             SLOGE("Failed to move mount (%s)", strerror(errno));
             umount("/mnt/secure/staging");
             setState(Volume::State_Idle);
             return -1;
         }
         setState(Volume::State_Mounted);
         mCurrentlyMountedKdev = deviceNodes[i];
         return 0;
     }

     SLOGE("Volume %s found no suitable devices for mounting :(\n", getLabel());
     setState(Volume::State_Idle);

     return -1;
 }

 int Volume::createBindMounts() {
     unsigned long flags;

     /*
      * Rename old /android_secure -> /.android_secure
      */
     if (!access("/mnt/secure/staging/android_secure", R_OK | X_OK) &&
          access(SEC_STG_SECIMGDIR, R_OK | X_OK)) {
         if (rename("/mnt/secure/staging/android_secure", SEC_STG_SECIMGDIR)) {
             SLOGE("Failed to rename legacy asec dir (%s)", strerror(errno));
         }
     }

     /*
      * Ensure that /android_secure exists and is a directory
      */
     if (access(SEC_STG_SECIMGDIR, R_OK | X_OK)) {
         if (errno == ENOENT) {
             if (mkdir(SEC_STG_SECIMGDIR, 0777)) {
                 SLOGE("Failed to create %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
                 return -1;
             }
         } else {
             SLOGE("Failed to access %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
             return -1;
         }
     } else {
         struct stat sbuf;

         if (stat(SEC_STG_SECIMGDIR, &sbuf)) {
             SLOGE("Failed to stat %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
             return -1;
         }
         if (!S_ISDIR(sbuf.st_mode)) {
             SLOGE("%s is not a directory", SEC_STG_SECIMGDIR);
             errno = ENOTDIR;
             return -1;
         }
     }

     /*
      * Bind mount /mnt/secure/staging/android_secure -> /mnt/secure/asec so we'll
      * have a root only accessable mountpoint for it.
      */
     if (mount(SEC_STG_SECIMGDIR, SEC_ASECDIR, "", MS_BIND, NULL)) {
         SLOGE("Failed to bind mount points %s -> %s (%s)",
                 SEC_STG_SECIMGDIR, SEC_ASECDIR, strerror(errno));
         return -1;
     }

     /*
      * Mount a read-only, zero-sized tmpfs  on <mountpoint>/android_secure to
      * obscure the underlying directory from everybody - sneaky eh? ;)
      */
     if (mount("tmpfs", SEC_STG_SECIMGDIR, "tmpfs", MS_RDONLY, "size=0,mode=000,uid=0,gid=0")) {
         SLOGE("Failed to obscure %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
         umount("/mnt/asec_secure");
         return -1;
     }

     return 0;
 }

 int Volume::doMoveMount(const char *src, const char *dst, bool force) {
     unsigned int flags = MS_MOVE;
     int retries = 5;

     while(retries--) {
         if (!mount(src, dst, "", flags, NULL)) {
             if (mDebug) {
                 SLOGD("Moved mount %s -> %s sucessfully", src, dst);
             }
             return 0;
         } else if (errno != EBUSY) {
             SLOGE("Failed to move mount %s -> %s (%s)", src, dst, strerror(errno));
             return -1;
         }
         int action = 0;

         if (force) {
             if (retries == 1) {
                 action = 2; // SIGKILL
             } else if (retries == 2) {
                 action = 1; // SIGHUP
             }
         }
         SLOGW("Failed to move %s -> %s (%s, retries %d, action %d)",
                 src, dst, strerror(errno), retries, action);
         Process::killProcessesWithOpenFiles(src, action);
         usleep(1000*250);
     }

     errno = EBUSY;
     SLOGE("Giving up on move %s -> %s (%s)", src, dst, strerror(errno));
     return -1;
 }

 int Volume::doUnmount(const char *path, bool force) {
     int retries = 10;

     if (mDebug) {
         SLOGD("Unmounting {%s}, force = %d", path, force);
     }

     while (retries--) {
         if (!umount(path) || errno == EINVAL || errno == ENOENT) {
             SLOGI("%s sucessfully unmounted", path);
             return 0;
         }

         int action = 0;

         if (force) {
             if (retries == 1) {
                 action = 2; // SIGKILL
             } else if (retries == 2) {
                 action = 1; // SIGHUP
             }
         }

         SLOGW("Failed to unmount %s (%s, retries %d, action %d)",
                 path, strerror(errno), retries, action);

         Process::killProcessesWithOpenFiles(path, action);
         usleep(1000*1000);
     }
     errno = EBUSY;
     SLOGE("Giving up on unmount %s (%s)", path, strerror(errno));
     return -1;
 }

 int Volume::unmountVol(bool force) {
     int i, rc;

     if (getState() != Volume::State_Mounted) {
         SLOGE("Volume %s unmount request when not mounted", getLabel());
         errno = EINVAL;
         return -1;
     }

     setState(Volume::State_Unmounting);
     usleep(1000 * 1000); // Give the framework some time to react

     /*
      * First move the mountpoint back to our internal staging point
      * so nobody else can muck with it while we work.
      */
     if (doMoveMount(getMountpoint(), SEC_STGDIR, force)) {
         SLOGE("Failed to move mount %s => %s (%s)", getMountpoint(), SEC_STGDIR, strerror(errno));
         setState(Volume::State_Mounted);
         return -1;
     }

     protectFromAutorunStupidity();

     /*
      * Unmount the tmpfs which was obscuring the asec image directory
      * from non root users
      */

     if (doUnmount(Volume::SEC_STG_SECIMGDIR, force)) {
         SLOGE("Failed to unmount tmpfs on %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
         goto fail_republish;
     }

     /*
      * Remove the bindmount we were using to keep a reference to
      * the previously obscured directory.
      */

     if (doUnmount(Volume::SEC_ASECDIR, force)) {
         SLOGE("Failed to remove bindmount on %s (%s)", SEC_ASECDIR, strerror(errno));
         goto fail_remount_tmpfs;
     }

     /*
      * Finally, unmount the actual block device from the staging dir
      */
     if (doUnmount(Volume::SEC_STGDIR, force)) {
         SLOGE("Failed to unmount %s (%s)", SEC_STGDIR, strerror(errno));
         goto fail_recreate_bindmount;
     }

     SLOGI("%s unmounted sucessfully", getMountpoint());

     setState(Volume::State_Idle);
     mCurrentlyMountedKdev = -1;
     return 0;

     /*
      * Failure handling - try to restore everything back the way it was
      */
 fail_recreate_bindmount:
     if (mount(SEC_STG_SECIMGDIR, SEC_ASECDIR, "", MS_BIND, NULL)) {
         SLOGE("Failed to restore bindmount after failure! - Storage will appear offline!");
         goto out_nomedia;
     }
 fail_remount_tmpfs:
     if (mount("tmpfs", SEC_STG_SECIMGDIR, "tmpfs", MS_RDONLY, "size=0,mode=0,uid=0,gid=0")) {
         SLOGE("Failed to restore tmpfs after failure! - Storage will appear offline!");
         goto out_nomedia;
     }
 fail_republish:
     if (doMoveMount(SEC_STGDIR, getMountpoint(), force)) {
         SLOGE("Failed to republish mount after failure! - Storage will appear offline!");
         goto out_nomedia;
     }

     setState(Volume::State_Mounted);
     return -1;

 out_nomedia:
     setState(Volume::State_NoMedia);
     return -1;
 }
 int Volume::initializeMbr(const char *deviceNode) {
     struct disk_info dinfo;

     memset(&dinfo, 0, sizeof(dinfo));

     if (!(dinfo.part_lst = (struct part_info *) malloc(MAX_NUM_PARTS * sizeof(struct part_info)))) {
         SLOGE("Failed to malloc prt_lst");
         return -1;
     }

     memset(dinfo.part_lst, 0, MAX_NUM_PARTS * sizeof(struct part_info));
     dinfo.device = strdup(deviceNode);
     dinfo.scheme = PART_SCHEME_MBR;
     dinfo.sect_size = 512;
     dinfo.skip_lba = 2048;
     dinfo.num_lba = 0;
     dinfo.num_parts = 1;

     struct part_info *pinfo = &dinfo.part_lst[0];

     pinfo->name = strdup("android_sdcard");
     pinfo->flags |= PART_ACTIVE_FLAG;
     pinfo->type = PC_PART_TYPE_FAT32;
     pinfo->len_kb = -1;

     int rc = apply_disk_config(&dinfo, 0);

     if (rc) {
         SLOGE("Failed to apply disk configuration (%d)", rc);
         goto out;
     }

  out:
     free(pinfo->name);
     free(dinfo.device);
     free(dinfo.part_lst);

     return rc;
 }
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <stdlib.h>
	#include <string.h>
	#include <dirent.h>
	#include <errno.h>
	#include <fcntl.h>

	#include <sys/types.h>
	#include <sys/stat.h>
	#include <sys/types.h>
	#include <sys/mman.h>
	#include <sys/mount.h>

	#include <linux/kdev_t.h>
	#include <linux/fs.h>

	#include <cutils/properties.h>

	#include <diskconfig/diskconfig.h>

	#define LOG_TAG "Vold"

	#include <cutils/log.h>

	#include "Volume.h"
	#include "VolumeManager.h"
	#include "ResponseCode.h"
	#include "Fat.h"
	#include "Process.h"

	extern "C" void dos_partition_dec(void const pp, struct dos_partition d);
	extern "C" void dos_partition_enc(void pp, struct dos_partition d);


	/*
	* Secure directory - stuff that only root can see
	*/
	const char *Volume::SECDIR = "/mnt/secure";

	/*
	* Secure staging directory - where media is mounted for preparation
	*/
	const char *Volume::SEC_STGDIR = "/mnt/secure/staging";

	/*
	* Path to the directory on the media which contains publicly accessable
	* asec imagefiles. This path will be obscured before the mount is
	* exposed to non priviledged users.
	*/
	const char *Volume::SEC_STG_SECIMGDIR = "/mnt/secure/staging/.android_secure";

	/*
	* Path to where only root can access asec imagefiles
	*/
	const char *Volume::SEC_ASECDIR = "/mnt/secure/asec";

	/*
	* Path to where secure containers are mounted
	*/
	const char *Volume::ASECDIR = "/mnt/asec";

	/*
	* Path to where OBBs are mounted
	*/
	const char *Volume::LOOPDIR = "/mnt/obb";

	static const char *stateToStr(int state) {
	if (state == Volume::State_Init)
	return "Initializing";
	else if (state == Volume::State_NoMedia)
	return "No-Media";
	else if (state == Volume::State_Idle)
	return "Idle-Unmounted";
	else if (state == Volume::State_Pending)
	return "Pending";
	else if (state == Volume::State_Mounted)
	return "Mounted";
	else if (state == Volume::State_Unmounting)
	return "Unmounting";
	else if (state == Volume::State_Checking)
	return "Checking";
	else if (state == Volume::State_Formatting)
	return "Formatting";
	else if (state == Volume::State_Shared)
	return "Shared-Unmounted";
	else if (state == Volume::State_SharedMnt)
	return "Shared-Mounted";
	else
	return "Unknown-Error";
	}

	Volume::Volume(VolumeManager vm, const char label, const char *mount_point) {
	mVm = vm;
	mDebug = false;
	mLabel = strdup(label);
	mMountpoint = strdup(mount_point);
	mState = Volume::State_Init;
	mCurrentlyMountedKdev = -1;
	mPartIdx = -1;
	}

	Volume::~Volume() {
	free(mLabel);
	free(mMountpoint);
	}

	void Volume::protectFromAutorunStupidity() {
	char filename[255];

	snprintf(filename, sizeof(filename), "%s/autorun.inf", SEC_STGDIR);
	if (!access(filename, F_OK)) {
	SLOGW("Volume contains an autorun.inf! - removing");
	/*
	* Ensure the filename is all lower-case so
	* the process killer can find the inode.
	* Probably being paranoid here but meh.
	*/
	rename(filename, filename);
	Process::killProcessesWithOpenFiles(filename, 2);
	if (unlink(filename)) {
	SLOGE("Failed to remove %s (%s)", filename, strerror(errno));
	}
	}
	}

	void Volume::setDebug(bool enable) {
	mDebug = enable;
	}

	dev_t Volume::getDiskDevice() {
	return MKDEV(0, 0);
	};

	dev_t Volume::getShareDevice() {
	return getDiskDevice();
	}

	void Volume::handleVolumeShared() {
	}

	void Volume::handleVolumeUnshared() {
	}

	int Volume::handleBlockEvent(NetlinkEvent *evt) {
	errno = ENOSYS;
	return -1;
	}

	void Volume::setState(int state) {
	char msg[255];
	int oldState = mState;

	if (oldState == state) {
	SLOGW("Duplicate state (%d)\n", state);
	return;
	}

	mState = state;

	SLOGD("Volume %s state changing %d (%s) -> %d (%s)", mLabel,
	oldState, stateToStr(oldState), mState, stateToStr(mState));
	snprintf(msg, sizeof(msg),
	"Volume %s %s state changed from %d (%s) to %d (%s)", getLabel(),
	getMountpoint(), oldState, stateToStr(oldState), mState,
	stateToStr(mState));

	mVm->getBroadcaster()->sendBroadcast(ResponseCode::VolumeStateChange,
	msg, false);
	}

	int Volume::createDeviceNode(const char *path, int major, int minor) {
	mode_t mode = 0660 \| S_IFBLK;
	dev_t dev = (major << 8) \| minor;
	if (mknod(path, mode, dev) < 0) {
	if (errno != EEXIST) {
	return -1;
	}
	}
	return 0;
	}

	int Volume::formatVol() {

	if (getState() == Volume::State_NoMedia) {
	errno = ENODEV;
	return -1;
	} else if (getState() != Volume::State_Idle) {
	errno = EBUSY;
	return -1;
	}

	if (isMountpointMounted(getMountpoint())) {
	SLOGW("Volume is idle but appears to be mounted - fixing");
	setState(Volume::State_Mounted);
	// mCurrentlyMountedKdev = XXX
	errno = EBUSY;
	return -1;
	}

	bool formatEntireDevice = (mPartIdx == -1);
	char devicePath[255];
	dev_t diskNode = getDiskDevice();
	dev_t partNode = MKDEV(MAJOR(diskNode), (formatEntireDevice ? 1 : mPartIdx));

	setState(Volume::State_Formatting);

	int ret = -1;
	// Only initialize the MBR if we are formatting the entire device
	if (formatEntireDevice) {
	sprintf(devicePath, "/dev/block/vold/%d:%d",
	MAJOR(diskNode), MINOR(diskNode));

	if (initializeMbr(devicePath)) {
	SLOGE("Failed to initialize MBR (%s)", strerror(errno));
	goto err;
	}
	}

	sprintf(devicePath, "/dev/block/vold/%d:%d",
	MAJOR(partNode), MINOR(partNode));

	if (mDebug) {
	SLOGI("Formatting volume %s (%s)", getLabel(), devicePath);
	}

	if (Fat::format(devicePath, 0)) {
	SLOGE("Failed to format (%s)", strerror(errno));
	goto err;
	}

	ret = 0;

	err:
	setState(Volume::State_Idle);
	return ret;
	}

	bool Volume::isMountpointMounted(const char *path) {
	char device[256];
	char mount_path[256];
	char rest[256];
	FILE *fp;
	char line[1024];

	if (!(fp = fopen("/proc/mounts", "r"))) {
	SLOGE("Error opening /proc/mounts (%s)", strerror(errno));
	return false;
	}

	while(fgets(line, sizeof(line), fp)) {
	line[strlen(line)-1] = '\0';
	sscanf(line, "%255s %255s %255s\n", device, mount_path, rest);
	if (!strcmp(mount_path, path)) {
	fclose(fp);
	return true;
	}

	}

	fclose(fp);
	return false;
	}

	int Volume::mountVol() {
	dev_t deviceNodes[4];
	int n, i, rc = 0;
	char errmsg[255];

	if (getState() == Volume::State_NoMedia) {
	snprintf(errmsg, sizeof(errmsg),
	"Volume %s %s mount failed - no media",
	getLabel(), getMountpoint());
	mVm->getBroadcaster()->sendBroadcast(
	ResponseCode::VolumeMountFailedNoMedia,
	errmsg, false);
	errno = ENODEV;
	return -1;
	} else if (getState() != Volume::State_Idle) {
	errno = EBUSY;
	return -1;
	}

	if (isMountpointMounted(getMountpoint())) {
	SLOGW("Volume is idle but appears to be mounted - fixing");
	setState(Volume::State_Mounted);
	// mCurrentlyMountedKdev = XXX
	return 0;
	}

	n = getDeviceNodes((dev_t *) &deviceNodes, 4);
	if (!n) {
	SLOGE("Failed to get device nodes (%s)\n", strerror(errno));
	return -1;
	}

	for (i = 0; i < n; i++) {
	char devicePath[255];

	sprintf(devicePath, "/dev/block/vold/%d:%d", MAJOR(deviceNodes[i]),
	MINOR(deviceNodes[i]));

	SLOGI("%s being considered for volume %s\n", devicePath, getLabel());

	errno = 0;
	setState(Volume::State_Checking);

	if (Fat::check(devicePath)) {
	if (errno == ENODATA) {
	SLOGW("%s does not contain a FAT filesystem\n", devicePath);
	continue;
	}
	errno = EIO;
	/* Badness - abort the mount */
	SLOGE("%s failed FS checks (%s)", devicePath, strerror(errno));
	setState(Volume::State_Idle);
	return -1;
	}

	/*
	* Mount the device on our internal staging mountpoint so we can
	* muck with it before exposing it to non priviledged users.
	*/
	errno = 0;
	if (Fat::doMount(devicePath, "/mnt/secure/staging", false, false, false,
	1000, 1015, 0702, true)) {
	SLOGE("%s failed to mount via VFAT (%s)\n", devicePath, strerror(errno));
	continue;
	}

	SLOGI("Device %s, target %s mounted @ /mnt/secure/staging", devicePath, getMountpoint());

	protectFromAutorunStupidity();

	if (createBindMounts()) {
	SLOGE("Failed to create bindmounts (%s)", strerror(errno));
	umount("/mnt/secure/staging");
	setState(Volume::State_Idle);
	return -1;
	}

	/*
	* Now that the bindmount trickery is done, atomically move the
	* whole subtree to expose it to non priviledged users.
	*/
	if (doMoveMount("/mnt/secure/staging", getMountpoint(), false)) {
	SLOGE("Failed to move mount (%s)", strerror(errno));
	umount("/mnt/secure/staging");
	setState(Volume::State_Idle);
	return -1;
	}
	setState(Volume::State_Mounted);
	mCurrentlyMountedKdev = deviceNodes[i];
	return 0;
	}

	SLOGE("Volume %s found no suitable devices for mounting :(\n", getLabel());
	setState(Volume::State_Idle);

	return -1;
	}

	int Volume::createBindMounts() {
	unsigned long flags;

	/*
	* Rename old /android_secure -> /.android_secure
	*/
	if (!access("/mnt/secure/staging/android_secure", R_OK \| X_OK) &&
	access(SEC_STG_SECIMGDIR, R_OK \| X_OK)) {
	if (rename("/mnt/secure/staging/android_secure", SEC_STG_SECIMGDIR)) {
	SLOGE("Failed to rename legacy asec dir (%s)", strerror(errno));
	}
	}

	/*
	* Ensure that /android_secure exists and is a directory
	*/
	if (access(SEC_STG_SECIMGDIR, R_OK \| X_OK)) {
	if (errno == ENOENT) {
	if (mkdir(SEC_STG_SECIMGDIR, 0777)) {
	SLOGE("Failed to create %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
	return -1;
	}
	} else {
	SLOGE("Failed to access %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
	return -1;
	}
	} else {
	struct stat sbuf;

	if (stat(SEC_STG_SECIMGDIR, &sbuf)) {
	SLOGE("Failed to stat %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
	return -1;
	}
	if (!S_ISDIR(sbuf.st_mode)) {
	SLOGE("%s is not a directory", SEC_STG_SECIMGDIR);
	errno = ENOTDIR;
	return -1;
	}
	}

	/*
	* Bind mount /mnt/secure/staging/android_secure -> /mnt/secure/asec so we'll
	* have a root only accessable mountpoint for it.
	*/
	if (mount(SEC_STG_SECIMGDIR, SEC_ASECDIR, "", MS_BIND, NULL)) {
	SLOGE("Failed to bind mount points %s -> %s (%s)",
	SEC_STG_SECIMGDIR, SEC_ASECDIR, strerror(errno));
	return -1;
	}

	/*
	* Mount a read-only, zero-sized tmpfs on <mountpoint>/android_secure to
	* obscure the underlying directory from everybody - sneaky eh? ;)
	*/
	if (mount("tmpfs", SEC_STG_SECIMGDIR, "tmpfs", MS_RDONLY, "size=0,mode=000,uid=0,gid=0")) {
	SLOGE("Failed to obscure %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
	umount("/mnt/asec_secure");
	return -1;
	}

	return 0;
	}

	int Volume::doMoveMount(const char src, const char dst, bool force) {
	unsigned int flags = MS_MOVE;
	int retries = 5;

	while(retries--) {
	if (!mount(src, dst, "", flags, NULL)) {
	if (mDebug) {
	SLOGD("Moved mount %s -> %s sucessfully", src, dst);
	}
	return 0;
	} else if (errno != EBUSY) {
	SLOGE("Failed to move mount %s -> %s (%s)", src, dst, strerror(errno));
	return -1;
	}
	int action = 0;

	if (force) {
	if (retries == 1) {
	action = 2; // SIGKILL
	} else if (retries == 2) {
	action = 1; // SIGHUP
	}
	}
	SLOGW("Failed to move %s -> %s (%s, retries %d, action %d)",
	src, dst, strerror(errno), retries, action);
	Process::killProcessesWithOpenFiles(src, action);
	usleep(1000*250);
	}

	errno = EBUSY;
	SLOGE("Giving up on move %s -> %s (%s)", src, dst, strerror(errno));
	return -1;
	}

	int Volume::doUnmount(const char *path, bool force) {
	int retries = 10;

	if (mDebug) {
	SLOGD("Unmounting {%s}, force = %d", path, force);
	}

	while (retries--) {
	if (!umount(path) \|\| errno == EINVAL \|\| errno == ENOENT) {
	SLOGI("%s sucessfully unmounted", path);
	return 0;
	}

	int action = 0;

	if (force) {
	if (retries == 1) {
	action = 2; // SIGKILL
	} else if (retries == 2) {
	action = 1; // SIGHUP
	}
	}

	SLOGW("Failed to unmount %s (%s, retries %d, action %d)",
	path, strerror(errno), retries, action);

	Process::killProcessesWithOpenFiles(path, action);
	usleep(1000*1000);
	}
	errno = EBUSY;
	SLOGE("Giving up on unmount %s (%s)", path, strerror(errno));
	return -1;
	}

	int Volume::unmountVol(bool force) {
	int i, rc;

	if (getState() != Volume::State_Mounted) {
	SLOGE("Volume %s unmount request when not mounted", getLabel());
	errno = EINVAL;
	return -1;
	}

	setState(Volume::State_Unmounting);
	usleep(1000 * 1000); // Give the framework some time to react

	/*
	* First move the mountpoint back to our internal staging point
	* so nobody else can muck with it while we work.
	*/
	if (doMoveMount(getMountpoint(), SEC_STGDIR, force)) {
	SLOGE("Failed to move mount %s => %s (%s)", getMountpoint(), SEC_STGDIR, strerror(errno));
	setState(Volume::State_Mounted);
	return -1;
	}

	protectFromAutorunStupidity();

	/*
	* Unmount the tmpfs which was obscuring the asec image directory
	* from non root users
	*/

	if (doUnmount(Volume::SEC_STG_SECIMGDIR, force)) {
	SLOGE("Failed to unmount tmpfs on %s (%s)", SEC_STG_SECIMGDIR, strerror(errno));
	goto fail_republish;
	}

	/*
	* Remove the bindmount we were using to keep a reference to
	* the previously obscured directory.
	*/

	if (doUnmount(Volume::SEC_ASECDIR, force)) {
	SLOGE("Failed to remove bindmount on %s (%s)", SEC_ASECDIR, strerror(errno));
	goto fail_remount_tmpfs;
	}

	/*
	* Finally, unmount the actual block device from the staging dir
	*/
	if (doUnmount(Volume::SEC_STGDIR, force)) {
	SLOGE("Failed to unmount %s (%s)", SEC_STGDIR, strerror(errno));
	goto fail_recreate_bindmount;
	}

	SLOGI("%s unmounted sucessfully", getMountpoint());

	setState(Volume::State_Idle);
	mCurrentlyMountedKdev = -1;
	return 0;

	/*
	* Failure handling - try to restore everything back the way it was
	*/
	fail_recreate_bindmount:
	if (mount(SEC_STG_SECIMGDIR, SEC_ASECDIR, "", MS_BIND, NULL)) {
	SLOGE("Failed to restore bindmount after failure! - Storage will appear offline!");
	goto out_nomedia;
	}
	fail_remount_tmpfs:
	if (mount("tmpfs", SEC_STG_SECIMGDIR, "tmpfs", MS_RDONLY, "size=0,mode=0,uid=0,gid=0")) {
	SLOGE("Failed to restore tmpfs after failure! - Storage will appear offline!");
	goto out_nomedia;
	}
	fail_republish:
	if (doMoveMount(SEC_STGDIR, getMountpoint(), force)) {
	SLOGE("Failed to republish mount after failure! - Storage will appear offline!");
	goto out_nomedia;
	}

	setState(Volume::State_Mounted);
	return -1;

	out_nomedia:
	setState(Volume::State_NoMedia);
	return -1;
	}
	int Volume::initializeMbr(const char *deviceNode) {
	struct disk_info dinfo;

	memset(&dinfo, 0, sizeof(dinfo));

	if (!(dinfo.part_lst = (struct part_info ) malloc(MAX_NUM_PARTS sizeof(struct part_info)))) {
	SLOGE("Failed to malloc prt_lst");
	return -1;
	}

	memset(dinfo.part_lst, 0, MAX_NUM_PARTS * sizeof(struct part_info));
	dinfo.device = strdup(deviceNode);
	dinfo.scheme = PART_SCHEME_MBR;
	dinfo.sect_size = 512;
	dinfo.skip_lba = 2048;
	dinfo.num_lba = 0;
	dinfo.num_parts = 1;

	struct part_info *pinfo = &dinfo.part_lst[0];

	pinfo->name = strdup("android_sdcard");
	pinfo->flags \|= PART_ACTIVE_FLAG;
	pinfo->type = PC_PART_TYPE_FAT32;
	pinfo->len_kb = -1;

	int rc = apply_disk_config(&dinfo, 0);

	if (rc) {
	SLOGE("Failed to apply disk configuration (%d)", rc);
	goto out;
	}

	out:
	free(pinfo->name);
	free(dinfo.device);
	free(dinfo.part_lst);

	return rc;
	}