1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/system/gonk/Volume.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,408 @@
1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this file,
1.6 + * You can obtain one at http://mozilla.org/MPL/2.0/. */
1.7 +
1.8 +#include "Volume.h"
1.9 +#include "VolumeCommand.h"
1.10 +#include "VolumeManager.h"
1.11 +#include "VolumeManagerLog.h"
1.12 +#include "nsIVolume.h"
1.13 +#include "nsXULAppAPI.h"
1.14 +
1.15 +#include <vold/ResponseCode.h>
1.16 +
1.17 +namespace mozilla {
1.18 +namespace system {
1.19 +
1.20 +Volume::EventObserverList Volume::mEventObserverList;
1.21 +
1.22 +// We have a feature where volumes can be locked when mounted. This
1.23 +// is used to prevent a volume from being shared with the PC while
1.24 +// it is actively being used (say for storing an update image)
1.25 +//
1.26 +// We use WakeLocks (a poor choice of name, but it does what we want)
1.27 +// from the PowerManagerService to determine when we're locked.
1.28 +// In particular we'll create a wakelock called volume-NAME-GENERATION
1.29 +// (where NAME is the volume name, and GENERATION is its generation
1.30 +// number), and if this wakelock is locked, then we'll prevent a volume
1.31 +// from being shared.
1.32 +//
1.33 +// Implementation Details:
1.34 +//
1.35 +// Since the AutoMounter can only control when something gets mounted
1.36 +// and not when it gets unmounted (for example: a user pulls the SDCard)
1.37 +// and because Volume and nsVolume data structures are maintained on
1.38 +// separate threads, we have the potential for some race conditions.
1.39 +// We eliminate the race conditions by introducing the concept of a
1.40 +// generation number. Every time a volume transitions to the Mounted
1.41 +// state, it gets assigned a new generation number. Whenever the state
1.42 +// of a Volume changes, we send the updated state and current generation
1.43 +// number to the main thread where it gets updated in the nsVolume.
1.44 +//
1.45 +// Since WakeLocks can only be queried from the main-thread, the
1.46 +// nsVolumeService looks for WakeLock status changes, and forwards
1.47 +// the results to the IOThread.
1.48 +//
1.49 +// If the Volume (IOThread) recieves a volume update where the generation
1.50 +// number mismatches, then the update is simply ignored.
1.51 +//
1.52 +// When a Volume (IOThread) initially becomes mounted, we assume it to
1.53 +// be locked until we get our first update from nsVolume (MainThread).
1.54 +static int32_t sMountGeneration = 0;
1.55 +
1.56 +// We don't get media inserted/removed events at startup. So we
1.57 +// assume it's present, and we'll be told that it's missing.
1.58 +Volume::Volume(const nsCSubstring& aName)
1.59 + : mMediaPresent(true),
1.60 + mState(nsIVolume::STATE_INIT),
1.61 + mName(aName),
1.62 + mMountGeneration(-1),
1.63 + mMountLocked(true), // Needs to agree with nsVolume::nsVolume
1.64 + mSharingEnabled(false),
1.65 + mCanBeShared(true),
1.66 + mIsSharing(false),
1.67 + mFormatRequested(false),
1.68 + mMountRequested(false),
1.69 + mUnmountRequested(false),
1.70 + mIsFormatting(false)
1.71 +{
1.72 + DBG("Volume %s: created", NameStr());
1.73 +}
1.74 +
1.75 +void
1.76 +Volume::SetIsSharing(bool aIsSharing)
1.77 +{
1.78 + if (aIsSharing == mIsSharing) {
1.79 + return;
1.80 + }
1.81 + mIsSharing = aIsSharing;
1.82 + LOG("Volume %s: IsSharing set to %d state %s",
1.83 + NameStr(), (int)mIsSharing, StateStr(mState));
1.84 + if (mIsSharing) {
1.85 + mEventObserverList.Broadcast(this);
1.86 + }
1.87 +}
1.88 +
1.89 +void
1.90 +Volume::SetIsFormatting(bool aIsFormatting)
1.91 +{
1.92 + if (aIsFormatting == mIsFormatting) {
1.93 + return;
1.94 + }
1.95 + mIsFormatting = aIsFormatting;
1.96 + LOG("Volume %s: IsFormatting set to %d state %s",
1.97 + NameStr(), (int)mIsFormatting, StateStr(mState));
1.98 + if (mIsFormatting) {
1.99 + mEventObserverList.Broadcast(this);
1.100 + }
1.101 +}
1.102 +
1.103 +void
1.104 +Volume::SetMediaPresent(bool aMediaPresent)
1.105 +{
1.106 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.107 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.108 +
1.109 + // mMediaPresent is slightly redunant to the state, however
1.110 + // when media is removed (while Idle), we get the following:
1.111 + // 631 Volume sdcard /mnt/sdcard disk removed (179:0)
1.112 + // 605 Volume sdcard /mnt/sdcard state changed from 1 (Idle-Unmounted) to 0 (No-Media)
1.113 + //
1.114 + // And on media insertion, we get:
1.115 + // 630 Volume sdcard /mnt/sdcard disk inserted (179:0)
1.116 + // 605 Volume sdcard /mnt/sdcard state changed from 0 (No-Media) to 2 (Pending)
1.117 + // 605 Volume sdcard /mnt/sdcard state changed from 2 (Pending) to 1 (Idle-Unmounted)
1.118 + //
1.119 + // On media removal while the media is mounted:
1.120 + // 632 Volume sdcard /mnt/sdcard bad removal (179:1)
1.121 + // 605 Volume sdcard /mnt/sdcard state changed from 4 (Mounted) to 5 (Unmounting)
1.122 + // 605 Volume sdcard /mnt/sdcard state changed from 5 (Unmounting) to 1 (Idle-Unmounted)
1.123 + // 631 Volume sdcard /mnt/sdcard disk removed (179:0)
1.124 + // 605 Volume sdcard /mnt/sdcard state changed from 1 (Idle-Unmounted) to 0 (No-Media)
1.125 + //
1.126 + // When sharing with a PC, it goes Mounted -> Idle -> Shared
1.127 + // When unsharing with a PC, it goes Shared -> Idle -> Mounted
1.128 + //
1.129 + // The AutoMounter needs to know whether the media is present or not when
1.130 + // processing the Idle state.
1.131 +
1.132 + if (mMediaPresent == aMediaPresent) {
1.133 + return;
1.134 + }
1.135 +
1.136 + LOG("Volume: %s media %s", NameStr(), aMediaPresent ? "inserted" : "removed");
1.137 + mMediaPresent = aMediaPresent;
1.138 + mEventObserverList.Broadcast(this);
1.139 +}
1.140 +
1.141 +void
1.142 +Volume::SetSharingEnabled(bool aSharingEnabled)
1.143 +{
1.144 + mSharingEnabled = aSharingEnabled;
1.145 +
1.146 + LOG("SetSharingMode for volume %s to %d canBeShared = %d",
1.147 + NameStr(), (int)mSharingEnabled, (int)mCanBeShared);
1.148 +}
1.149 +
1.150 +void
1.151 +Volume::SetFormatRequested(bool aFormatRequested)
1.152 +{
1.153 + mFormatRequested = aFormatRequested;
1.154 +
1.155 + LOG("SetFormatRequested for volume %s to %d CanBeFormatted = %d",
1.156 + NameStr(), (int)mFormatRequested, (int)CanBeFormatted());
1.157 +}
1.158 +
1.159 +void
1.160 +Volume::SetMountRequested(bool aMountRequested)
1.161 +{
1.162 + mMountRequested = aMountRequested;
1.163 +
1.164 + LOG("SetMountRequested for volume %s to %d CanBeMounted = %d",
1.165 + NameStr(), (int)mMountRequested, (int)CanBeMounted());
1.166 +}
1.167 +
1.168 +void
1.169 +Volume::SetUnmountRequested(bool aUnmountRequested)
1.170 +{
1.171 + mUnmountRequested = aUnmountRequested;
1.172 +
1.173 + LOG("SetUnmountRequested for volume %s to %d CanBeMounted = %d",
1.174 + NameStr(), (int)mUnmountRequested, (int)CanBeMounted());
1.175 +}
1.176 +
1.177 +void
1.178 +Volume::SetState(Volume::STATE aNewState)
1.179 +{
1.180 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.181 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.182 + if (aNewState == mState) {
1.183 + return;
1.184 + }
1.185 + if (aNewState == nsIVolume::STATE_MOUNTED) {
1.186 + mMountGeneration = ++sMountGeneration;
1.187 + LOG("Volume %s: changing state from %s to %s @ '%s' (%d observers) "
1.188 + "mountGeneration = %d, locked = %d",
1.189 + NameStr(), StateStr(mState),
1.190 + StateStr(aNewState), mMountPoint.get(), mEventObserverList.Length(),
1.191 + mMountGeneration, (int)mMountLocked);
1.192 + } else {
1.193 + LOG("Volume %s: changing state from %s to %s (%d observers)",
1.194 + NameStr(), StateStr(mState),
1.195 + StateStr(aNewState), mEventObserverList.Length());
1.196 + }
1.197 +
1.198 + switch (aNewState) {
1.199 + case nsIVolume::STATE_NOMEDIA:
1.200 + // Cover the startup case where we don't get insertion/removal events
1.201 + mMediaPresent = false;
1.202 + mIsSharing = false;
1.203 + mUnmountRequested = false;
1.204 + mMountRequested = false;
1.205 + break;
1.206 +
1.207 + case nsIVolume::STATE_MOUNTED:
1.208 + mMountRequested = false;
1.209 + mIsFormatting = false;
1.210 + mIsSharing = false;
1.211 + break;
1.212 + case nsIVolume::STATE_FORMATTING:
1.213 + mFormatRequested = false;
1.214 + mIsFormatting = true;
1.215 + mIsSharing = false;
1.216 + break;
1.217 +
1.218 + case nsIVolume::STATE_SHARED:
1.219 + case nsIVolume::STATE_SHAREDMNT:
1.220 + // Covers startup cases. Normally, mIsSharing would be set to true
1.221 + // when we issue the command to initiate the sharing process, but
1.222 + // it's conceivable that a volume could already be in a shared state
1.223 + // when b2g starts.
1.224 + mIsSharing = true;
1.225 + break;
1.226 +
1.227 + case nsIVolume::STATE_IDLE:
1.228 + break;
1.229 + default:
1.230 + break;
1.231 + }
1.232 + mState = aNewState;
1.233 + mEventObserverList.Broadcast(this);
1.234 +}
1.235 +
1.236 +void
1.237 +Volume::SetMountPoint(const nsCSubstring& aMountPoint)
1.238 +{
1.239 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.240 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.241 +
1.242 + if (mMountPoint.Equals(aMountPoint)) {
1.243 + return;
1.244 + }
1.245 + mMountPoint = aMountPoint;
1.246 + DBG("Volume %s: Setting mountpoint to '%s'", NameStr(), mMountPoint.get());
1.247 +}
1.248 +
1.249 +void
1.250 +Volume::StartMount(VolumeResponseCallback* aCallback)
1.251 +{
1.252 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.253 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.254 +
1.255 + StartCommand(new VolumeActionCommand(this, "mount", "", aCallback));
1.256 +}
1.257 +
1.258 +void
1.259 +Volume::StartUnmount(VolumeResponseCallback* aCallback)
1.260 +{
1.261 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.262 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.263 +
1.264 + StartCommand(new VolumeActionCommand(this, "unmount", "force", aCallback));
1.265 +}
1.266 +
1.267 +void
1.268 +Volume::StartFormat(VolumeResponseCallback* aCallback)
1.269 +{
1.270 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.271 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.272 +
1.273 + StartCommand(new VolumeActionCommand(this, "format", "", aCallback));
1.274 +}
1.275 +
1.276 +void
1.277 +Volume::StartShare(VolumeResponseCallback* aCallback)
1.278 +{
1.279 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.280 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.281 +
1.282 + StartCommand(new VolumeActionCommand(this, "share", "ums", aCallback));
1.283 +}
1.284 +
1.285 +void
1.286 +Volume::StartUnshare(VolumeResponseCallback* aCallback)
1.287 +{
1.288 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.289 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.290 +
1.291 + StartCommand(new VolumeActionCommand(this, "unshare", "ums", aCallback));
1.292 +}
1.293 +
1.294 +void
1.295 +Volume::StartCommand(VolumeCommand* aCommand)
1.296 +{
1.297 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.298 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.299 +
1.300 + VolumeManager::PostCommand(aCommand);
1.301 +}
1.302 +
1.303 +//static
1.304 +void
1.305 +Volume::RegisterObserver(Volume::EventObserver* aObserver)
1.306 +{
1.307 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.308 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.309 +
1.310 + mEventObserverList.AddObserver(aObserver);
1.311 + // Send an initial event to the observer (for each volume)
1.312 + size_t numVolumes = VolumeManager::NumVolumes();
1.313 + for (size_t volIndex = 0; volIndex < numVolumes; volIndex++) {
1.314 + RefPtr<Volume> vol = VolumeManager::GetVolume(volIndex);
1.315 + aObserver->Notify(vol);
1.316 + }
1.317 +}
1.318 +
1.319 +//static
1.320 +void
1.321 +Volume::UnregisterObserver(Volume::EventObserver* aObserver)
1.322 +{
1.323 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.324 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.325 +
1.326 + mEventObserverList.RemoveObserver(aObserver);
1.327 +}
1.328 +
1.329 +//static
1.330 +void
1.331 +Volume::UpdateMountLock(const nsACString& aVolumeName,
1.332 + const int32_t& aMountGeneration,
1.333 + const bool& aMountLocked)
1.334 +{
1.335 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.336 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.337 +
1.338 + RefPtr<Volume> vol = VolumeManager::FindVolumeByName(aVolumeName);
1.339 + if (!vol || (vol->mMountGeneration != aMountGeneration)) {
1.340 + return;
1.341 + }
1.342 + if (vol->mMountLocked != aMountLocked) {
1.343 + vol->mMountLocked = aMountLocked;
1.344 + DBG("Volume::UpdateMountLock for '%s' to %d\n", vol->NameStr(), (int)aMountLocked);
1.345 + mEventObserverList.Broadcast(vol);
1.346 + }
1.347 +}
1.348 +
1.349 +void
1.350 +Volume::HandleVoldResponse(int aResponseCode, nsCWhitespaceTokenizer& aTokenizer)
1.351 +{
1.352 + MOZ_ASSERT(XRE_GetProcessType() == GeckoProcessType_Default);
1.353 + MOZ_ASSERT(MessageLoop::current() == XRE_GetIOMessageLoop());
1.354 +
1.355 + // The volume name will have already been parsed, and the tokenizer will point
1.356 + // to the token after the volume name
1.357 + switch (aResponseCode) {
1.358 + case ResponseCode::VolumeListResult: {
1.359 + // Each line will look something like:
1.360 + //
1.361 + // sdcard /mnt/sdcard 1
1.362 + //
1.363 + nsDependentCSubstring mntPoint(aTokenizer.nextToken());
1.364 + SetMountPoint(mntPoint);
1.365 + nsresult errCode;
1.366 + nsCString state(aTokenizer.nextToken());
1.367 + if (state.EqualsLiteral("X")) {
1.368 + // Special state for creating fake volumes which can't be shared.
1.369 + mCanBeShared = false;
1.370 + SetState(nsIVolume::STATE_MOUNTED);
1.371 + } else {
1.372 + SetState((STATE)state.ToInteger(&errCode));
1.373 + }
1.374 + break;
1.375 + }
1.376 +
1.377 + case ResponseCode::VolumeStateChange: {
1.378 + // Format of the line looks something like:
1.379 + //
1.380 + // Volume sdcard /mnt/sdcard state changed from 7 (Shared-Unmounted) to 1 (Idle-Unmounted)
1.381 + //
1.382 + // So we parse out the state after the string " to "
1.383 + while (aTokenizer.hasMoreTokens()) {
1.384 + nsAutoCString token(aTokenizer.nextToken());
1.385 + if (token.Equals("to")) {
1.386 + nsresult errCode;
1.387 + token = aTokenizer.nextToken();
1.388 + SetState((STATE)token.ToInteger(&errCode));
1.389 + break;
1.390 + }
1.391 + }
1.392 + break;
1.393 + }
1.394 +
1.395 + case ResponseCode::VolumeDiskInserted:
1.396 + SetMediaPresent(true);
1.397 + break;
1.398 +
1.399 + case ResponseCode::VolumeDiskRemoved: // fall-thru
1.400 + case ResponseCode::VolumeBadRemoval:
1.401 + SetMediaPresent(false);
1.402 + break;
1.403 +
1.404 + default:
1.405 + LOG("Volume: %s unrecognized reponse code (ignored)", NameStr());
1.406 + break;
1.407 + }
1.408 +}
1.409 +
1.410 +} // namespace system
1.411 +} // namespace mozilla
