Hi!
I wanted to reformat my internal sdcard to ext4 today to enable trimming (it should also help the /data partition, because it is on the same physical flash storage, right?).
To back up my data I thought about packing everything into a TAR archive to also save all permissions (for example of the ./Android/data/ folder). But now I have the following problem:
if I browse through /storage/sdcard0, I see all the permissions and the correct owners, but I dont have access to .android_secure. I am using a adb root shell, how can I not have access to this?!
if I browse through /mnt/media_rw/sdcard0, I have access to .android_secure, but all the file owners are set to "media_rw", which is not what I want to backup, I need the correct owner info to correctly restore the data later.
Could you please help me to answer these questions?:
As I understand, FAT doesnt support permissions, so how does android emulate the permissions in the ./Android/data folder?
How can I see the same folder (my internal sdcard) with different file owners? Is it mounted twice with special options?
How can I backup my whole sdcard (with owner/group info & permissions & file access dates) to restore everything 1:1 after reformating to ext4?
How do I reformat my sdcard to ext4? (which block device comes after "mkfs.ext4"?)
Thank you very much!!
GridLockFour said:
Hi!
I wanted to reformat my internal sdcard to ext4 today to enable trimming (it should also help the /data partition, because it is on the same physical flash storage, right?).
To back up my data I thought about packing everything into a TAR archive to also save all permissions (for example of the ./Android/data/ folder). But now I have the following problem:
if I browse through /storage/sdcard0, I see all the permissions and the correct owners, but I dont have access to .android_secure. I am using a adb root shell, how can I not have access to this?!
if I browse through /mnt/media_rw/sdcard0, I have access to .android_secure, but all the file owners are set to "media_rw", which is not what I want to backup, I need the correct owner info to correctly restore the data later.
Could you please help me to answer these questions?:
As I understand, FAT doesnt support permissions, so how does android emulate the permissions in the ./Android/data folder?
How can I see the same folder (my internal sdcard) with different file owners? Is it mounted twice with special options?
How can I backup my whole sdcard (with owner/group info & permissions & file access dates) to restore everything 1:1 after reformating to ext4?
How do I reformat my sdcard to ext4? (which block device comes after "mkfs.ext4"?)
Thank you very much!!
Click to expand...
Click to collapse
I'm not sure the answer to some of that, but you don't need ext4 for trimming(EDIT: although I don't know whether android enables trim on FAT) and /data is already ext4 by default. The /data partition is separate to /sdcard0
Most if not all gains from trimming would be made from trimming /system, /data, /cache, and /preload(if you use touchwiz based rom or stock)
Related
Hi I am using Modaco Rom 3.1 with A2SD with Ext3.
I am wondering how do I go about extracting application data, such as chat logs from MSN Droid or notes from Ultramate, from the SD card? Where is application data saved on A2SD on android devices and how could I copy them to my computer? I don't want to back up the data, I just want to be able to view them on my computer.
Any help would be greatly appreciated, thanks.
application data is usually stored in /data/data, but could also go to the fat partition of the card (the part you see on your windows pc when you mount the usb storage) if it is larger data (for example trailmaps saves the downloaded ski area maps on the fat partition), because space in /data is limited.
you can pull it via adb pull and then examine the file, afaik these are usually sqlite databases, but that is only afaik and could vary from app to app.
Thanks kendong2 I managed to pull the data.
But out of curiosity, is this /data/data partition part of the phone's memory, or of the SD card's? I can't seem to browse it using a file manager.
And do applications store any data in the Ext3 partition of the SD card?
/data is part of the phone memory, it is readable only by root. get root explorer or any file manager that uses root and you can read it.
only apps themselves are stored on ext, no data. unless you specify it, which would require modifying the apps2sd script (kinda like "data2sd").
My sdcard(class 4 8gb sandisk) is causing problems with fat32 fs...i use debian all the time and wud like to have a much advanced fs like ext4 for saving my music,videos,pictures etc instead of fat32...how can i achieve taht...Does android use a fstab or something for mounting on boot ???
I'm quite sure android uses fstab for mounting, you just need to set the proper mounting option on your FS to force it to check fstab options. I have one question(since I don't use a linux machine), can you access your ext(2nd) partition(if you have one) when you connect your phone to the PC using debian?
Yep,Android uses fstab to mount all.
anybody interested in setting it up i dont have the requisite knowhow
I have not toyed with fstab myself... but I did find this page which seems to have want your looking for.
http://androidandme.com/2009/08/news/how-to-manually-partition-your-sd-card-for-android-apps2sd/
It isn't exactly what your explaining, BUT seems to go through the commands needed for what you are wanting to try.
Just remember to back up! Good luck!
Sent from my LG-P500 using XDA App
Instructions:
-Suggested at least fat32 partition to be 1gig and the rest to your ext partition. Also, try to use root explorer for everything else. Must have init.d support.
1. On your SD card, make a folder to serve as a door/portal to access your ext partition files.(When testing this, I just used the default "/sdcard/media" folder)
2. Make a blank text file and name it as "11usext"
3. Using root explorer, edit the file and add this line inside it:
Code:
#!/system/bin/sh
busybox mount -t auto /dev/block/mmcblk0p2 /mnt/sdcard/media
change media to the folder that you just made on step 1. Exit and save.
4. Using root explorer move this file to /system/etc/init.d
5. Again using root explorer, change the permission to "rwxrwxrwx"
6. Reboot and play. This would allow you to access your ext partition through the /media or the folder that you have created.
If this does not work, then you should give more details on what setup you are running.
ungaze said:
Instructions:
-Suggested at least fat32 partition to be 1gig and the rest to your ext partition. Also, try to use root explorer for everything else. Must have init.d support.
1. On your SD card, make a folder to serve as a door/portal to access your ext partition files.(When testing this, I just used the default "/sdcard/media" folder)
2. Make a blank text file and name it as "11usext"
3. Using root explorer, edit the file and add this line inside it:
Code:
#!/system/bin/sh
busybox mount -t auto /dev/block/mmcblk0p2 /mnt/sdcard/media
change media to the folder that you just made on step 1. Exit and save.
4. Using root explorer move this file to /system/etc/init.d
5. Again using root explorer, change the permission to "rwxrwxrwx"
6. Reboot and play. This would allow you to access your ext partition through the /media or the folder that you have created.
If this does not work, then you should give more details on what setup you are running.
Click to expand...
Click to collapse
That's a quite dirty implementation. All he want's is an ext4 partition mounted as /sdcard. I want to do the same, but right now I'm messing with the internal fs. I'll look into it.
That's a quite dirty implementation.
Click to expand...
Click to collapse
Dirty it might be(I even tried a dirtier one), but that's all he's got at the moment. If you have a better solution(even just a rough plan), please do share. Maybe we can exchange knowledge on stuff like these.
Using 2 Ext4 partitions on SD instead of one Ext+fat32
Click to expand...
Click to collapse
Would mean that no Fat32 partition exist, and I've never heard of anything like that.
I have one question(since I don't use a linux machine), can you access your ext(2nd) partition(if you have one) when you connect your phone to the PC using debian?
Click to expand...
Click to collapse
And since no one answered this, I have no idea how you could transfer files to your phone without using card readers.
ungaze said:
Dirty it might be(I even tried a dirtier one), but that's all he's got at the moment. If you have a better solution(even just a rough plan), please do share. Maybe we can exchange knowledge on stuff like these.
Click to expand...
Click to collapse
Probably it involves messing with the init.rc (and I think that involves messing with boot and recovery images, but, I'm not sure) or init.d scripts or fstab. Anyway, I'm not sure, but it should be possible.
ungaze said:
Would mean that no Fat32 partition exist, and I've never heard of anything like that.
Click to expand...
Click to collapse
Yes. The /sdcard partition would exist, just not fat32 formatted.
ungaze said:
And since no one answered this, I have no idea how you could transfer files to your phone without using card readers.
Click to expand...
Click to collapse
Linux systems can read and write to ext4 partitions without problems. In fact, it's a linux filesystem. I had problems once when I had a sd_ext partition (for Apps2SD), because both partitions would get mounted when using mass storage mode, while Android only unmounts the /sdcard (fat32) partition, leading to file corruption (because of the same partition being mounted on both systems at once).
We could create the partitions using gparted or cfdisk on a pc. I'm not sure, but maybe simply mounting it with different params (like the filesystem type and other options) at /sdcard would do the trick. Everything else that follows would be easy.
I've been doing some testing and research.
On recovery side:
I've done a little modification in Mik's ClockWork recovery to make it accept ext4 and vfat as valid file systems for the first partition on sdcard. It involves just a little change on /etc/recovery.fstab file, but then you need to rebuild the recovery image.
This is working fine.
On the OS side:
It's not an easy mod. It involves patching the vold (volume manager) and recompiling. There are some proposed patches to Cyanogenmod, but I don't know if it's been accepted and if it made it to Miks CM7 port.
I'll do some tests and post results.
ilarrain said:
I've been doing some testing and research.
On recovery side:
I've done a little modification in Mik's ClockWork recovery to make it accept ext4 and vfat as valid file systems for the first partition on sdcard. It involves just a little change on /etc/recovery.fstab file, but then you need to rebuild the recovery image.
This is working fine.
On the OS side:
It's not an easy mod. It involves patching the vold (volume manager) and recompiling. There are some proposed patches to Cyanogenmod, but I don't know if it's been accepted and if it made it to Miks CM7 port.
I'll do some tests and post results.
Click to expand...
Click to collapse
This got my interest
Mik's CM7 (beta 6.2) recognizes and mounts the ext4 partition just fine.
BUT:
As vfat is a non posix fs, there wasn't any need for the OS to manage permissions, so it's a mess.
Applications on the SD card (I'm not using Apps2SD or Data2SD) don't load, internal applications can't be moved to SD, and many apps can't store data on the SD, even I've set read+write permissions on all files and directories (chmod -R 777 /sdcard/). I have no idea why. I'm stuck.
Hi.
I've rooted my A70s with chulri's kernel and it seems to work ok.
My next goal is to get more app room ... so I guess I need to resize the app/data partition.
I've thought that having my internal storage formatted on ext4, it would be possible to ln the /data folder to /storage/data without problems, but then I should create a boot script for that. The question is... can I do this with my current root status? What would be the way to do it? I'm don't know enough of linux os to make it on my own.
If the system can't be fooled with a ln, then is there any way to resize the data partition, even if I have to backup/restore my current data?
I don't want to use Urukdroid, since all the versions I tried were very unstable on my machine.
Cheers!!
search the forum: http://forum.xda-developers.com/showthread.php?p=14710945#post14710945
Follow chulri's method, or repartition your internal storage in Linux, mount it on the archos, and copy the data there. Then edit init.rc and change the data mount line. If it gets mounted in the kernel, you'll have to umount it first to remount it to the other partition.
our device is a data/media device which is why usb mount don't work
here's a link that explains it all
http://teamw.in/DataMedia
and part of the convo with dees_troy is below
<Dees_Troy> Nope, it will *never* work on a data/media device
<Dees_Troy> read and learn: http://teamw.in/DataMedia
<WinBot> [Link] http://tinyw.in/lstO :: What is a data media device? | TeamWin
<Dees_Troy> definitely worth understanding
<Dees_Troy> at some point we're going to try to kang in MTP for recovery
<Lloir> so for now then it's sideload or from inside the rom
<Dees_Troy> or adb push
<Lloir> aye
<Dees_Troy> or gtfo
<*****> so cant mount usb storage with newer devices...hmm one x did guess this is where confusion at least on my part came to be
<Lloir> lmao Dees_Troy
<Dees_Troy> one x wasn't a data media device
YOU MUST either transfer the rom\boot\porn\audio\mods while the phone is on or use adb push or even sideload when in recovery, THIS IS THE ONLY way
What is a media device?
Thanks, I have copied the text from the link for easy reading.
What is a data media device?
I'm writing this page because there seems to be a lot of confusion about how many of the newer Android devices work. Starting in Honeycomb 3.0 with the Xoom, Google changed the way that they handled storage. Instead of having a "data" partition with your apps and a separate "sdcard" partition for storage, Google started giving you a single, very large data partition. Inside /data is a folder at /data/media that contains all of the contents of what you think of as your internal sdcard.
Since /data/media is part of /data, we pretty much never actually format the data partition. Formatting data, of course, also removes the media folder that contains the internal sdcard. When you choose a factory reset, instead of formatting, we use rm -rf commands to remove all the folders except for the media folder so that we can remove all of your apps and settings while leaving your "sdcard" intact. In TWRP we also have a wipe internal storage option that rm -rf's the media folder and a "Format Data" option that formats to recreate the entire file system in case something goes completely wrong or to remove device encryption.
When you're booted to Android, Android fuses the media folder to /sdcard and emulates a FAT files system that doesn't have permissions for legacy apps. We don't currently have fuse in recovery, so we just add an extra mount command to mount /data/media to /sdcard so in recovery you still have to worry about permissions on /sdcard.
Because the "internal sdcard" is not a true FAT file system, you can't mount it via USB storage. Well, that's not technically true, but the vast majority of people use Windows computers and Windows doesn't recognize ext4. If we were to allow you to mount the data partition via USB storage, Windows would claim that the device wasn't formatted and offer to format it for you, which, as you can imagine, would be a disaster. The whole ext4 setup is another reason that Android switched to using MTP for transferring files. Most of these devices don't have the necessary kernel configuration to even support USB storage mode, so it's not very easy to enable USB storage if we even wanted to try. Unfortunately at this time, MTP isn't available in recovery, so if you have no other option, you will have to use adb to push and pull files to/from your device.
As a special note, if you choose to do a factory reset from your ROM, even if the ROM says that it will wipe everything including the internal storage, well, that's not what TWRP will do. A stock AOSP recovery would format data including the "sdcard" but TWRP will use its regular factory reset setup that leaves the internal storage intact.
There are a couple of nice gains with using this setup vs the old data + FAT storage partition. With /data/media you, as the user get more control over how you use your storage. If you have a ton of apps, then that's no problem since you have a huge data partition to work with. If you don't have a lot of apps, you get more room to use for storing things like movies. Further, ext4 doesn't suffer from the 4GB file size limit that FAT has, so you can have a large, high-def movie on your device if you like. I'm sure another motivating factor was to get Android away from using FAT which is a Microsoft creation. Performance on ext4 in Android is also probably better than FAT. As a downside, data media devices tend to store a lot more app data in the "data" section and so backups on these devices tend to be larger.
Click to expand...
Click to collapse
any guide how to put a file on phone if it does not boot? (ie adb push or while in recovery please)
Not so bad, i can live with that
(P.s.: Lloir i've ended the script, now it's working! )
thanks dude
Greetings.
I have formatted /mnt/sdcard as EXT2.
How do I setup default permissions (-rwxrwxrwx) for all market apps to use when they create files there?
_______________________________________________
Details:
My device is LG e405 (rooted stock Android 2.3-based firmware, no stable custom ROMs exist for the device)
I cannot use an external SD-card for now and the device has a very small /data partition (150 MB, half of which is used up by stock software)
I would like to have data (photos, etc) AND programs (APKs) on the same partition. I really hate running out of space on one partition when the other one is half-free.
I know that some programs can be "moved to SD", but not only not all of them can be moved - even if they can they still leave some files on /data, and those tend to quickly pile up.
So I formatted /sdcard as EXT2 and symlinked /data/app to /sdcard/dataapp. I now do have everything on one partition.
It works fine, except that normal android programs create files with permissions of "600" ("-rw-------"), which prevents other programs from reading them. So Gallery cannot access photos that Camera just took.
Is it possible to set default permissions for new files?
Thank you very much for your answers!