Database Develop

[Dev] Research on native ext4 partition

* Update * - 02/28/2012
I had a little chat with one of Archos dev, he told me that mmcblk0p3 was his gift for us!
So, what does it mean:
1) Archos is very developer friendly. We've known that already, but having them leaving us such entries in their tablet is very nice to see!
2) He told me that mmcblk0p3 isn't and won't be used by Archos firmware, we're completely free to use it like we want with SDE
3) With this partition, we can do very nice things, see below
Here is what can be done:
1) delete p3 and p4
2) recreate p3 as extended with any size we want
3) recreate p4 with what remains.
4) on extended p3, we can create p5, p6, ...
I did that on mine, I now have a 8 MB p5 for cwmod, a 380M p6 for rootfs+system, without any interference with stock firmware!
If someone wants to experiment with that, few advices:
- Be careful when you re-create p3 and p4, there is an empty space that should remain empty in the partition table (it contains bootloader). So when you recreate p3, you have to use the same start sector as before, not the one proposed by default.
- When you re-create p4, make sure that you use end of p3 + 1 as start for the same reason.
- Don't do fdisk if you have partition mounted, it would confuse kernel and could be dangerous. You need a specific initramfs to be able to do that.
- This is still very dangerous, be warned! invalid partition table and your tablet is toaster. Only change it if you know exactly what you're doing
As a sample, here is my current partition table:
Code:
Disk /dev/block/mmcblk0: 7457 MB, 7457472512 bytes
4 heads, 16 sectors/track, 227584 cylinders
Units = cylinders of 64 * 512 = 32768 bytes
Device Boot Start End Blocks Id System
/dev/block/mmcblk0p1 5 1605 51200+ 83 Linux
/dev/block/mmcblk0p2 1605 10760 292969+ 83 Linux
/dev/block/mmcblk0p3 10760 22967 390625+ 5 Extended
/dev/block/mmcblk0p4 22967 227584 6547764 83 Linux
/dev/block/mmcblk0p5 10760 11004 7813 83 Linux
/dev/block/mmcblk0p6 11004 22967 382796+ 83 Linux
------------
Previous text:
Hello All,
As I saw some interest in running firmware directly from ext4 partition, I'd like to share what I found out while I was toying with my tablet:
Having ext4 on gen9 is not as easy as gen8: gen8 has two virtual mmcs on top of a single physical mmc with a split managed at kernel level. So what was done was to reduce storage partition to add ext4 system and/or data partition. More, on gen8, SDE exports storage mmc as a disk to the host allowing resizing partitions in linux for instance.
We can't do that on Gen9: Gen9 has a single physical mmc, part 1 is rawfs, part 2 is system and too short to have unpacked system, part 3 is a very small unused small one, part 4 is data.
On top of part 4, there is an Archos specific trick that remaps /data/media to /storage, explaining why we don't have the same limit on data partition and that /data and /storage are sharing same space. And SDE doesn't export disk.
BIG WARNING BEFORE TRYING ANYTHING: DON'T TOUCH PARTITION 1, NEVER. If partition 1 is trashed or damaged, device is bricked definitively.
So, what is possible is to trash part 2, 3, 4 and re-create a different layout or trash part 4, create two or three extended partitions instead.
If you go option 1, it would have to be done completely from an initrd as you would kill the os you're running on . Option two could be done from adb if Android is properly stopped, but I didn't test it and don't know if kernel and/or Android are behaving well with extended partitions.
Personally, I did it a third way, I modified archos recovery: recovery has a special code that repartition disk if things goes very bad. I changed partition layout builded there, then trashed my partitions and go to recovery to have it re-created. This method has advantages, the partition layout is permanent, meaning that if for some reason I trash one partition it will be re-created with the right size.
However, it has many disadvantages: You have to be able to flash rawfs to be able to flash a recovery, and it's a bit hectic and dangerous to force the partition re-creation. That's why I didn't share it and probably won't as you really need to know what you're doing if you don't want a big brick.
Last thing, I didn't see that much improvement in speed compared to other methods like having a loopback on internal storage, not sure it's really worth the effort and the risks. I did it because I don't like loopbacks, but frankly, having it done safely is much efforts.

Good post.
Thanks for the information

it is great

Hi letama,
interesting thread again
letama said:
Having ext4 on gen9 is not as easy as gen8: gen8 has two virtual mmcs on top of a single physical mmc with a split managed at kernel level. So what was done was to reduce storage partition to add ext4 system and/or data partition. More, on gen8, SDE exports storage mmc as a disk to the host allowing resizing partitions in linux for instance.
Click to expand...
Click to collapse
Nothing to add...
I found out that a second mbr is placed at the beginning of the "virtual" mmc block device 1. So the internal eMMC chip of the Gen8 devices additionally requires a special layout.
letama said:
We can't do that on Gen9: Gen9 has a single physical mmc, part 1 is rawfs, part 2 is system and too short to have unpacked system, part 3 is a very small unused small one, part 4 is data.
Click to expand...
Click to collapse
Going down to hardware level, it seems that Archos went back to use raw NAND flashes instead of eMMC for the Gen9 devices.
I found a FCC document of the Archos 80 G9 showing one 8GByte NAND flash device placed on the mainboard.
Could be a prototype as well...
Additionally it could be possible, that the mtd block layout is already handled inside bootcode.
Anyway, what does a cat /proc/partitions print out?
Regards,
scholbert

/proc/partitions:
Code:
major minor #blocks name
7 0 159412 loop0
179 0 7282688 mmcblk0
179 1 51200 mmcblk0p1
179 2 195359 mmcblk0p2
179 3 7840 mmcblk0p3
179 4 7028160 mmcblk0p4

Hi Scholbert,
scholbert said:
interesting thread again
Click to expand...
Click to collapse
Thanks!
scholbert said:
Nothing to add...
I found out that a second mbr is placed at the beginning of the "virtual" mmc block device 1. So the internal eMMC chip of the Gen8 devices additionally requires a special layout.
Click to expand...
Click to collapse
Well, kind of, it's not really a special layout. From userspace linux point of view, the two virtual mmcs are regular disks, they could be formatted, partitioned, etc.
The mmc driver is doing all the "magic" (mmc_block.split kernel command line parameter):
- for virtual mmc0, virtual sector is mapped to physical sector 0 - split
- for virtual mmc1, virtual sector is mapped to physical sector split - end.
So, the second mbr is coming from a regular disk initialization, nothing special.
scholbert said:
Going down to hardware level, it seems that Archos went back to use raw NAND flashes instead of eMMC for the Gen9 devices.
Click to expand...
Click to collapse
We're still eMMC afaik.
scholbert said:
Additionally it could be possible, that the mtd block layout is already handled inside bootcode.
Click to expand...
Click to collapse
No, gen9 has regular partition scheme, I was able to repartition it without problem... The only difficulty is to do it without killing the device by accident as if you want to keep the 4 partitions layout, you have to kill system and data (and data means also internal storage) partitions, be sure that you don't kill rawfs partition in the process then rebuild them.
Nothing very complicated per se, I would do a ram only initrd with backup of system/data/storage via adb or on microsd. However, as microsd slot is not completely stable for me, the fullly automated option is a bit risky.
My /proc/partitions is this now
Code:
major minor #blocks name
179 0 7282688 mmcblk0
179 1 51200 mmcblk0p1
179 2 439487 mmcblk0p2
179 3 7840 mmcblk0p3
179 4 6784032 mmcblk0p4

Hi Letama,
I see you have modify your part scheme but mmcblk0p2 is your android root part (like loop img) ?
You have rewrite your bootloader ? or just android kernel/initramfs (not SDE kernel/initramfs) ?
Have a nice day !
Thaolia

Hi Tha0lia,
Yes, my p2 is now rootfs+system, it's the content of the img, but directly on the partition, formatted as ext4.
No, it's not the bootloader, bootloader doesn't know anything about partition layout.
Like I explained, I did it by patching the recovery as it will recreate partitions if it detects if a partition is missing. Then, I deleted my system and data partition, rebooted in recovery to have it recreate the whole disk. Last was to modify SDE/Main kernel initrd to mount this partition instead of the loopback device.
You can't do this if you don't have a tool to flash recovery/main kernel. I wrote one, but as it's very dangerous for the tablet, I'm reluctant to let it out.
Back on the subject, this is something that could be done with sde only with a properly written initrd. The only downside is that if for some reason recovery detects a partition problem, it will revert to the old layout, but it should work. The other downside is that "stock boot" on main kernel will only work if you dedicate enough space to hold both the squashfs and the rootfs files. Mine doesn't have too as I modified also stock boot, but again, to do that, you need to flash rawfs init file and special flasher.
I don't have enough time (and energy, enough formats these days ) to do the SDE initrd right now, we'll see if someone takes the baby and if it's really worth it.

Woaw ! Good work ! Thanks for the complementary informations.
So my hack ("abcbox reboot_into -s sde" at boot) is more secure than flash rawfs if i have understood well.
Last question (sry ^^"), but do you have made a serial connection with your tablet for debugging or dev your rawfs flasher ?

letama said:
Well, kind of, it's not really a special layout. From userspace linux point of view, the two virtual mmcs are regular disks, they could be formatted, partitioned, etc.
The mmc driver is doing all the "magic" (mmc_block.split kernel command line parameter):
- for virtual mmc0, virtual sector is mapped to physical sector 0 - split
- for virtual mmc1, virtual sector is mapped to physical sector split - end.
So, the second mbr is coming from a regular disk initialization, nothing special.
Click to expand...
Click to collapse
Yeah sure, i just wanted to point at that mbr...
letama said:
We're still eMMC afaik.
Click to expand...
Click to collapse
Considering the device names it seems eMMC is used, makes sense as this is newer/better technology.
Maybe the FCC doc is of interested.
See attachment... on this device a NAND flash (H27UCG8UDA) is used.
This is definitely raw NAND.
So maybe this is a pre-series model...
letama said:
No, gen9 has regular partition scheme, I was able to repartition it without problem... The only difficulty is to do it without killing the device by accident as if you want to keep the 4 partitions layout, you have to kill system and data (and data means also internal storage) partitions, be sure that you don't kill rawfs partition in the process then rebuild them.
Nothing very complicated per se, I would do a ram only initrd with backup of system/data/storage via adb or on microsd. However, as microsd slot is not completely stable for me, the fullly automated option is a bit risky.
Click to expand...
Click to collapse
Your power supply should be fail-safe at this point
letama said:
My /proc/partitions is this now
Code:
major minor #blocks name
179 0 7282688 mmcblk0
179 1 51200 mmcblk0p1
179 2 439487 mmcblk0p2
179 3 7840 mmcblk0p3
179 4 6784032 mmcblk0p4
Click to expand...
Click to collapse
Yeah cool stuff... still on my Gen8 though.
Keep on hackin'
scholbert

So my hack ("abcbox reboot_into -s sde" at boot) is more secure than flash rawfs if i have understood well.
Last question (sry ^^"), but do you have made a serial connection with your tablet for debugging or dev your rawfs flasher ?
Click to expand...
Click to collapse
Yes, the reboot_into -s sde is a good solution to keep booting on sde...
Unfortunately, no, I don't have serial connection. I'd love to have one, not really for rawfs flashing, it's not that difficult, but more for kernel dev, it would help a lot. But opening stuff and soldering things is not my best skill, I'm a bit reluctant to do it yet, at least without a backup device handy

Hi Scholbert!
scholbert said:
See attachment... on this device a NAND flash (H27UCG8UDA) is used.
This is definitely raw NAND.
So maybe this is a pre-series model...
Click to expand...
Click to collapse
Yes, maybe... Someday I'll get the courage to open up this thing, I'm sure
scholbert said:
Your power supply should be fail-safe at this point
Click to expand...
Click to collapse
Better be!
Well, in fact, it's not such a big deal if it crashes in the middle, recovery will handle partition rebuild, but oups, reformat, flash again stock, re-root, re-enable sde, reflash sde initrd, retry, .... better be.
Yeah cool stuff... still on my Gen8 though.
Click to expand...
Click to collapse
Good news coming from this front

A little up, I updated first post with some news...

Nice
So what are default (safe) offsets?

gen_scheisskopf said:
Nice
So what are default (safe) offsets?
Click to expand...
Click to collapse
Well, don't do anything before end of mmcblk0p2 end block (10760 if you stay in default fdisk mode). Check your partition table before to get the proper value, mine is not a good example as it has been resized before to 300M, normal is 200M.
Basically, get your current mmcblk0p3 start and reuse this number (you may need +1, but fdisk will adjust)

Hey letama,
i'm in with my new A80 G9.
Quite nice device, but also suffering a little on this display issue.
Don't care much because... you may guess it already... i'm going to look inside the next days.
I'm a bit afraid though, because everything is held together with these plastic clamps. Hopefully i'm not gonna break anything.
Anyway a new thread will be born soon and i'll report my findings (boot_mode signals & other stuff ).
Enough small talk...
As you pointed out you are using a real ext4 partition already.
This might be my plan as well, because i don't like this loop mounting on real devices as well.
Yesterday i installed the latest ICS ext4 image file from surdu_petru.
So if i understand it correct this attempt is basically pretty similar to SDE image on Gen8.
If i got it right stock (unrooted squashfs image) and custom (rooted ext4 image) share the same data partition in this case.
What if we reduce size of mmcblk0p4 to increase mmcblk0p3, put our custom rootfs in it as a real filesystem.
Why did you increase mmcblk0p2 instead... in this case we'll have to wipe the stock image completely, right?
So no dual boot anymore...
Could you leave some thoughts on this?
Best regards,
scholbert

Hi Scholbert,
scholbert said:
i'm in with my new A80 G9.
Quite nice device, but also suffering a little on this display issue.
Don't care much because... you may guess it already... i'm going to look inside the next days.
Click to expand...
Click to collapse
Cool! Nice to have you onboard with g9!
Yesterday i installed the latest ICS ext4 image file from surdu_petru.
So if i understand it correct this attempt is basically pretty similar to SDE image on Gen8.
If i got it right stock (unrooted squashfs image) and custom (rooted ext4 image) share the same data partition in this case.
Click to expand...
Click to collapse
You purchased SD or HD model ?
Anyway, no, on both models, squashfs.secure is on p2 system partition, rooted ext4 is on data on p4 (internal storage is also on data for SD model) .
What if we reduce size of mmcblk0p4 to increase mmcblk0p3, put our custom rootfs in it as a real filesystem.
Click to expand...
Click to collapse
Yes, that's what I did. You can use p3 as ext4 directly, or you can use p3 as extended and create 3 partitions into this extended partition like I did. Check first post at the top, you'll see that, p3 extended, with p5, p6, p7 (p8 doesn't work). Benefit is that you dual boot on two custom rom and I needed a separate cache partition for clockworkmod recovery.
Why did you increase mmcblk0p2 instead... in this case we'll have to wipe the stock image completely, right?
So no dual boot anymore...
Click to expand...
Click to collapse
This was my first tentative, it was before Archos told me that p3 is for us and that we can do whatever we want with it. As I didn't know that, I didn't touch p3, extended p2, and put both squashfs.secure and my unpacked rooted build on it. Dual boot was working, but it's less elegant than what I currently have.
PS: if you do that, be careful when you reformat p4, you have to leave unused blocks at the end for drm I guess. Check recovery, it has the math.
If you want, I can give you my script to do it. I can even give you my ram only initrd with adb+cwm, you can then umount everything from adb then re-partition and format properly. Without ram only, you won't be able to umount and kernel will not refresh partition table.
PPS: careful with empty space for bootloader

Hey letama!
letama said:
You purchased SD or HD model ?
Click to expand...
Click to collapse
SD model, don't like moving parts in mobile devices.
letama said:
Anyway, no, on both models, squashfs.secure is on p2 system partition, rooted ext4 is on data on p4 (internal storage is also on data for SD model) .
Click to expand...
Click to collapse
Yeah sure... i refered to the loop mount of an ext4 file.
I knew it got stored on p4, so this partition is used for different purpose then and no fat anymore.
letama said:
Yes, that's what I did. You can use p3 as ext4 directly, or you can use p3 as extended and create 3 partitions into this extended partition like I did. Check first post at the top, you'll see that, p3 extended, with p5, p6, p7 (p8 doesn't work). Benefit is that you dual boot on two custom rom and I needed a separate cache partition for clockworkmod recovery.
Click to expand...
Click to collapse
Mmmh o.k. tweaking p3 and p4 would be sufficient i guess.
After shrinking p4, it would be a nice idea to use:
p3 = extended
p5 = system
p6 = data (seperated for the custom system)
Some mountpoints will have to be tweaked then...
letama said:
This was my first tentative, it was before Archos told me that p3 is for us and that we can do whatever we want with it. As I didn't know that, I didn't touch p3, extended p2, and put both squashfs.secure and my unpacked rooted build on it. Dual boot was working, but it's less elegant than what I currently have.
Click to expand...
Click to collapse
O.k. got it. I agree that p3 is a gift.
letama said:
PS: if you do that, be careful when you reformat p4, you have to leave unused blocks at the end for drm I guess. Check recovery, it has the math.
Click to expand...
Click to collapse
Thanks for the hint, i'll step through the scripts first
letama said:
If you want, I can give you my script to do it. I can even give you my ram only initrd with adb+cwm, you can then umount everything from adb then re-partition and format properly. Without ram only, you won't be able to umount and kernel will not refresh partition table.
Click to expand...
Click to collapse
Would be helpful indeed, thanks a lot for offering need my mail address.
May send you a PM.
letama said:
PPS: careful with empty space for bootloader
Click to expand...
Click to collapse
Thanks for the warning but i'm aware of this Archos specialty.
Best regards,
scholbert

scholbert said:
Mmmh o.k. tweaking p3 and p4 would be sufficient i guess.
After shrinking p4, it would be a nice idea to use:
p3 = extended
p5 = system
p6 = data (seperated for the custom system)
Click to expand...
Click to collapse
Don't forget about /cache- CWM needs it.
Or /cache as ramdisk?
scholbert said:
Some mountpoints will have to be tweaked then...
Click to expand...
Click to collapse
Only in kernel init, stock recovery won't touch p3 and p5-7 unless partition table would have to be rebuild (BTW- in ICS p2 size is increased from 200 to 300 MB)

gen_scheisskopf said:
Don't forget about /cache- CWM needs it.
Or /cache as ramdisk?
Click to expand...
Click to collapse
Yeah maybe better preserve some additional bytes.
Tough i won't use CWM for now.
gen_scheisskopf said:
Only in kernel init, stock recovery won't touch p3 and p5-7 unless partition table would have to be rebuild (BTW- in ICS p2 size is increased from 200 to 300 MB)
Click to expand...
Click to collapse
O.K. i see...
Interesting fact about p2.
To my surprise i'm still on ~200MB for p2 while running ICS on my pad.
The console gives me disk usage of 94% for p2 though.
Did it like this:
- my device came with HC installed
- used the temp root
- activated SDE by flashing letama's kernel and initramfs
- removed temp root
- rebooted into recovery
- removed stock HC, by wiping all related partitions
- installed stock ICS from recovery
- booted into stock ICS
- transfered rooted ICS ext4 image to p4
- rebooted to recovery
- used developer edition menu to reflashed the related kernel and initramfs
In the end i got dual-boot via recovery... stock and custom rooted
Something to be afraid of?
Regards,
scholbert

Repartition + FUSE in the next build of CM10

Hello,
I think it would be interesting in the next buid of CM10 implement FUSE.
For those not familiar with FUSE, this makes the EMMC (Internal) and DATA partitions are one.
FUSE is the standard in new android devices like the Galaxy S3.
With this gain in space, since both would have 6.7 GB of user data (photos for example) and for applications.
This would require using a repartitioning and as it should be, we could give more space to the partition and Partition System Cache.
I made a build with FUSE on, and doing great. It should be a standard in CM10 for P990.
A greeting and I apologize for the translation.

no thanks, i really like having my system and sd card separated...

60nine said:
no thanks, i really like having my system and sd card separated...
Click to expand...
Click to collapse
Sorry, SDCARD is the defaul name for internal.
FUSE = (Internal EMMC + DATA)
Without FUSE:
Partition 8 = DATA [1,5GB]
Partition 9 = EMMC [5,3 GB]
With FUSE only have:
Partition 8 = USERDATA [6,8 GB]
The user can see 6,8 GB in Internal SD

Sounds good but will it work,
If you want the CM team to pick it up you will have to talk with them directly.
Good luck
Sent from my LG-P990 using xda app-developers app

Tamps said:
Sounds good but will it work,
If you want the CM team to pick it up you will have to talk with them directly.
Good luck
Sent from my LG-P990 using xda app-developers app
Click to expand...
Click to collapse
Only change two files, and they here in the p990 repo.
Other solution is clone a p990, change two files and create a p990-fuse repo.

why would i fuse those two partitions? they are fine like they are now.
if i want to format the internal storage without affecting apps data i can while i'm using the actual partitions set, i cannot with the new mixed one.
this fuse leads what advantages?

pidocchio said:
why would i fuse those two partitions? they are fine like they are now.
if i want to format the internal storage without affecting apps data i can while i'm using the actual partitions set, i cannot with the new mixed one.
this fuse leads what advantages?
Click to expand...
Click to collapse
- You can format only DATA, and can format only EMMC too with FUSE with CWM.
- When you use a file manager, you see the same that without FUSE but you have 6,7GB.
- You can install 6,7 GB of APP.
- FUSE is ANDROID standard. All new Android devices use FUSE.

sounds great. make a flashable zip, we'll start using it

Sure
I'd give it a try i have a device i can use for testing

Ok,
I'll upload a zip with NVFlash and partitions.
Anyone can upload misc and lgdrm partitions?
Open Terminal
su
dd if=/dev/block/mmcblk0p3 of=/storage/sdcard0/misc.img
dd if=/dev/block/mmcblk0p6 of=/storage/sdcard0/lgdrm.img
After doing this, in the internal memory of the device, there should be two new files: lgdrm.img and misc.img.
Screenshot:
http://imageshack.us/photo/my-images/90/screenshot2012110410465.png/
http://imageshack.us/photo/my-images/12/screenshot2012110410462.png/

ProgMaq said:
Ok,
I'll upload a zip with NVFlash and partitions.
Anyone can upload misc and lgdrm partitions?
Open Terminal
su
dd if=/dev/block/mmcblk0p3 of=/storage/sdcard0/misc.img
dd if=/dev/block/mmcblk0p6 of=/storage/sdcard0/lgdrm.img
After doing this, in the internal memory of the device, there should be two new files: lgdrm.img and misc.img.
Screenshot:
http://imageshack.us/photo/my-images/90/screenshot2012110410465.png/
http://imageshack.us/photo/my-images/12/screenshot2012110410462.png/
Click to expand...
Click to collapse
misc.img: http://www.mediafire.com/?ik7gq8ddxxx0ujz
lgdrm.img: http://www.mediafire.com/?mf6oe0mio7xh9g9
I hope they are useful

Very thanks Chuck Bartowski
But your lgdrm.img is empty when mount.
This occurs when you have used nVFlash, not a problem, but I would like the original partition lgdrm compare with mine.
Anyone can upload original misc and lgdrm.
Thanks.

What about usb storage(internal storage) mounting after FUSING ?
Will it work as before ?
Sent from my Galaxy Nexus using xda premium

ProgMaq said:
Very thanks Chuck Bartowski
But your lgdrm.img is empty when mount.
This occurs when you have used nVFlash, not a problem, but I would like the original partition lgdrm compare with mine.
Anyone can upload original misc and lgdrm.
Thanks.
Click to expand...
Click to collapse
Ok, sorry, I didn't know.
I have reflash 10b with NVflash ( stock partition ), ROOT and Recovery, and I have flash cm10.
misc.img: http://www.mediafire.com/?1n0pmdbembdeorr
lgdrm.img: http://www.mediafire.com/?dan8jpucxjdw4ok

Chuck Bartowski said:
Ok, sorry, I didn't know.
I have reflash 10b with NVflash ( stock partition ), ROOT and Recovery, and I have flash cm10.
misc.img: http://www.mediafire.com/?1n0pmdbembdeorr
lgdrm.img: http://www.mediafire.com/?dan8jpucxjdw4ok
Click to expand...
Click to collapse
Thanks again, but even installing the stock version, the misc partition lgdrm and do not return to be the same (missing files)
What about usb storage(internal storage) mounting after FUSING ?
Will it work as before ?
Click to expand...
Click to collapse
Working same
Good news, I have uploaded the file. Zip
http://forum.xda-developers.com/showthread.php?p=33671985

Take a look at this link
teamw.in/DataMedia
So i think we might loose usb mounting on pc
Sent from my LG-P990 using xda app-developers app

ProgMaq said:
Sorry, SDCARD is the defaul name for internal.
FUSE = (Internal EMMC + DATA)
Without FUSE:
Partition 8 = DATA [1,5GB]
Partition 9 = EMMC [5,3 GB]
With FUSE only have:
Partition 8 = USERDATA [6,8 GB]
The user can see 6,8 GB in Internal SD
Click to expand...
Click to collapse
and still - i like it as it is
i still have 2 partitions with 6,8 GB total - but i can keep things more organized with 2 partitions than with one...
for me it's just like having 2+ PC harddrives - one only for the system, and other disks for the other files...

how do I flsh this to files with nvflash?

instead of fuse of internal memory(1.5gb) n internal sd(5.5gb).....
can i have fuse of internal sd(5.5gb) n external sd(i have 16gb) so that i can get...
external sd---21.5gb....
imo 1.5gb is enough for app data but 5.5gb is not enough for sd data files(nova 3 almost 2gb)
i hav mounted my externalsd as internalsd so that sd data files are saved in ext but 16gb not enough(game addict)...
hope u can help..thanks

ullekh99 said:
instead of fuse of internal memory(1.5gb) n internal sd(5.5gb).....
can i have fuse of internal sd(5.5gb) n external sd(i have 16gb) so that i can get...
external sd---21.5gb....
imo 1.5gb is enough for app data but 5.5gb is not enough for sd data files(nova 3 almost 2gb)
i hav mounted my externalsd as internalsd so that sd data files are saved in ext but 16gb not enough(game addict)...
hope u can help..thanks
Click to expand...
Click to collapse
I like it ,interesting thought
But what will hapn when sd ejected and phone restarted
Sent from my LG-P990 using xda app-developers app

32gb - how much is usable for storage?

I have a S2 16gb with 11.5gb usable "usb internal storage". Will Htc One have at least 28gb?

bubu_bubu said:
I have a S2 16gb with 11.5gb usable "usb internal storage". Will Htc One have at least 28gb?
Click to expand...
Click to collapse
It's about 26GB.

Jesus 6gb used?

bubu_bubu said:
Jesus 6gb used?
Click to expand...
Click to collapse
Indeed this has been confirmed. Bearing in mind if you install a custom Rom you can probs decrease this amount.
Sent from my Incredible S using Tapatalk 2

It is fine in my opinion. Most of the apps you install goes into that occupied 6 gigs anyway

I would get the 64gb version but I don't think the carriers in my country will have it

Dharkan said:
It is fine in my opinion. Most of the apps you install goes into that occupied 6 gigs anyway
Click to expand...
Click to collapse
No, storage is unified: apps go in the 26. (I think).

Oh if that's the case it really don't make much sense. I mean what would they use 6 gigs for, I don't believe smartphones are getting that big updates.

26.1gb is free to be precise lol and 1.5gb RAM

Dharkan said:
It is fine in my opinion. Most of the apps you install goes into that occupied 6 gigs anyway
Click to expand...
Click to collapse
source of your information?
If it has 2 partitions and one acts like the onboard (6gigs), and the other one (26) acts like a sd or whatever it would be ok ..
otherwise it's just like with the surface tablets .. well not quite as bad, but still a bit silly^^

If im correct on my HTC One X which was 32GB, i only had 22GB free after jelly bean update and 6GB or so for apps..
so the apps and sd storage is split

Shasarak said:
No, storage is unified: apps go in the 26. (I think).
Click to expand...
Click to collapse
Wrong
Got this from the stock recovery posted here on dev section when I extracted it.
Code:
# mount point fstype device [device2]
/boot emmc boot
/cache ext4 cache
/data ext4 userdata
/misc emmc misc
/recovery emmc recovery
/sdcard vfat /dev/block/sda1 /dev/block/sda
/system ext4 system
/devlog ext4 devlog
/reserve vfat reserve
Shows that /data(userdata) partition where apps get's installed has a seperation partition that needs to be mounted. So nope it's not unified.
and yeah for the developers who plan on extracting kernels/recovery of HTC One here are the info you need.
Code:
BOARD_KERNEL_CMDLINE is "console=ttyHSL0,115200,n8 androidboot.hardware=m7 user_debug=31"
BOARD_KERNEL_BASE is "0x80600000"
BOARD_PAGE_SIZE is "2048"

26 gigs is more than enough for me, I take up 5 to 6 on music alone and the rest on pictures and videos taken on phone, not much is taken with apps downloaded at the most 1gb so I'm quite comfortable with the amount of space on the phone although it would be awesome to have 28 or 29gb free
P.s. I do listen to all that music that takes up 5 to 6gb of space on my current phone in case some of you are wondering whether I listen to most of it wasting space on all that music
Sent from my HTC One S

I think it would be possible to repartition the /system partition to reduce it's size and merge it with the sdcard partition. Depends on the partition table. But if it's not possible I think we could also split the system partition and make a sd-ext there instead. But of course that's very dangerous and is not recommended on average users.

Riyal said:
Wrong
Got this from the stock recovery posted here on dev section when I extracted it.
Code:
# mount point fstype device [device2]
/boot emmc boot
/cache ext4 cache
/data ext4 userdata
/misc emmc misc
/recovery emmc recovery
/sdcard vfat /dev/block/sda1 /dev/block/sda
/system ext4 system
/devlog ext4 devlog
/reserve vfat reserve
Shows that /data(userdata) partition where apps get's installed has a seperation partition that needs to be mounted. So nope it's not unified.
and yeah for the developers who plan on extracting kernels/recovery of HTC One here are the info you need.
Code:
BOARD_KERNEL_CMDLINE is "console=ttyHSL0,115200,n8 androidboot.hardware=m7 user_debug=31"
BOARD_KERNEL_BASE is "0x80600000"
BOARD_PAGE_SIZE is "2048"
Click to expand...
Click to collapse
I stand corrected.
Though, also a little surprised. Weren't HTC's flagship phones last year unified? That seems a retrograde step.

Shasarak said:
No, storage is unified: apps go in the 26. (I think).
Click to expand...
Click to collapse
In HOX the memory WAS NOT unified.
Anybody knows how many storage is free for apps?
P.D. Sorry, I reply to the post before full read the thread. Cancelling my reservation.

JmJ17 said:
In HOX the memory WAS NOT unified.
Anybody knows how many storage is free for apps?
P.D. Sorry, I reply to the post before full read the thread. Cancelling my reservation.
Click to expand...
Click to collapse
Wild guess is 2GB.
2GB data partition
12mb devlog
17mb kernel
17mb recovery
120mb cache
rest is system partition

On my one x i had around 11 usable, and i still have 2 gb free. so if i get the one , ill have around 17 gb of free space holy moly .. what can i do with so much free space, can i rent it out?

jags_the1 said:
On my one x i had around 11 usable, and i still have 2 gb free. so if i get the one , ill have around 17 gb of free space holy moly .. what can i do with so much free space, can i rent it out?
Click to expand...
Click to collapse
give it to me I need more extra space.

That's awful. Why did they go back from the awesome unified space in the HOX+. Thats was so great. If you had free space you could install apps. If the One really has an apps partition again, I'm going to have to move apps to sd-card again the whole time
Why did they make a step backwards?

Please kindly help me, I am in very big trouble, Please help me bro………………

It is a long story. I bought a galaxy note n7000 from London with Gingerbread 2.3.5. After coming to my home country I informed that it is updated to ICS 4.0.3. As I was very new in smart world I did a very big mistake I had a super brick but spending 7 days I somehow revive it losing almost 5 GB internal memory.
I used this thread to do that:
http://forum.xda-developers.com/showthread.php?p=26285877#post26285877
After that I was using ICS indian official rom for 5 to six month.
In the process that I did I removed the 12 number hidden partition maybe called preload like:
Number Start End Size File system Name Flags
1 4194kB 25.2MB 21.0MB ext4 EFS
2 25.2MB 26.5MB 1311kB SBL1
3 27.3MB 28.6MB 1311kB SBL2
4 29.4MB 37.7MB 8389kB PARAM
5 37.7MB 46.1MB 8389kB KERNEL
6 46.1MB 54.5MB 8389kB RECOVERY
7 54.5MB 264MB 210MB ext4 CACHE
8 264MB 281MB 16.8MB MODEM
9 281MB 1174MB 893MB ext4 FACTORYFS
10 1174MB 3322MB 2147MB ext4 DATAFS
11 3322MB 15.2GB 11.9GB fat32 UMS
12 15.2GB 15.8GB 537MB ext4 HIDDEN
As the author of the thread said that:
It is also known that the hidden partition (partition 12) is not needed for normal use and install of roms. So you can delete it and enlarge the UMS partition (to 15800mb) and you will have a larger sdcard to use.
But I think the above information is wrong as I never find Snote application in my rom as it need this hidden part. But apart I did not find any problem.
Now when I got jelly bean 4.1.2 update over kies I did that and got in a big problem. I tried 50 times 10 different roms but got bootloop every time. After searching a lot I came to know that the hidden preload is essential for jelly bean so I started the ADB program and use the Samsung official pit files and got back the hidden preload part.
Then I load jelly bean rom by odin a well it started good.
Now everything is fine but I got a problem that I never get before.
If I turn on the wifi my phone stuck, it freeze completely unlit I reboot it, I Thought it is jelly bean roam problem but no I got the same problem in ICS also the rom I used 4 month without any problem.
Yah I got some experience in last one year, and I revive my phone from super brick alone so I have some knowledge a I used all in this problem but no luck.
I can inform U that I have tried all general solutions for that
So please is there any kind person who knows this problem specifically and give the right solution.
I am in very big trouble, Please help me bro………………

the problem could be:
when you get a brick, portion of the system partition gets corrupted. so you used a workaround to bypass this portion using the modified PIT files. then you used an original PIT file which may have activated these again and now then system is reading these bad blocks and getting errors. so you may need to use the scanners again and use a modified PIT .. if doing this manually this time, donot remove the hidden partition.. As the guide was written when ICS and it didnot use preload.. but JB is too huge to accommodate in the System partition so uses preload for a lot of apps..

Repartition is a "workaround" with these limitations. You should really consider a mainboard replacement seriously now.
---------- Post added at 01:05 PM ---------- Previous post was at 12:37 PM ----------
Hey, stop posting this now everywhere in Custom Rom threads. It is enough if you make a thread in Q&A, no need to spam the development forum!

Thnaks Brother
nokiamodeln91 said:
the problem could be:
when you get a brick, portion of the system partition gets corrupted. so you used a workaround to bypass this portion using the modified PIT files. then you used an original PIT file which may have activated these again and now then system is reading these bad blocks and getting errors. so you may need to use the scanners again and use a modified PIT .. if doing this manually this time, donot remove the hidden partition.. As the guide was written when ICS and it didnot use preload.. but JB is too huge to accommodate in the System partition so uses preload for a lot of apps..
Click to expand...
Click to collapse
I did the repartition and every partition is checked by ADB and formatted with no error and my phone is running on ICS now everything owrking fine but once I turn on wifi the phone become bit hot and hang right away

did you try installing a different kernel like speedmod

Problem Identified but not solution
nokiamodeln91 said:
did you try installing a different kernel like speedmod
Click to expand...
Click to collapse
The problem is in internal memory, I already lost 6 gb internal memory, rest of them checked by adb and no problem but it has some probllem , there is some bad sectors that adb could not identifi so whenever my phone wants to read or write something in internal memory it hangs,
solution is to change the 16GB internal memory, but the question is it possible to do so, if I change the mother board will it chane the full memory also?????????????

Yeah. Changing the motherboard will do

i also encountered same problem..
i even used repartitioning
i think the work around solution is not a long term one..
replacing the motherboard is the main solution but its like buying a mid range phone
so now my phone is in my closet..
i wonder after replacing the mainboard, would the emmc bug still exist?..

Thnaks Brother
jaycm1130 said:
i also encountered same problem..
i even used repartitioning
i think the work around solution is not a long term one..
replacing the motherboard is the main solution but its like buying a mid range phone
so now my phone is in my closet..
i wonder after replacing the mainboard, would the emmc bug still exist?..
Click to expand...
Click to collapse
Dear Bro,
Sorry to say I don not have warranty. After three days working what I understand that the main problem is the DATAFS partition just that is all, but It is impossible to find out that in the 16GB memory where this DATAFS will be fine, after a long work I reduced the DATAFS to 900MB and upto now phone is working fine. But I know that It is not the final solution, I will some how try to change the EMMC disk or the full mother board as soon as possible.
Thanks again for ur reply

I.am.zahid said:
Dear Bro,
Sorry to say I don not have warranty. After three days working what I understand that the main problem is the DATAFS partition just that is all, but It is impossible to find out that in the 16GB memory where this DATAFS will be fine, after a long work I reduced the DATAFS to 900MB and upto now phone is working fine. But I know that It is not the final solution, I will some how try to change the EMMC disk or the full mother board as soon as possible.
Thanks again for ur reply
Click to expand...
Click to collapse
yes.. were facing same problem.. i feel you..
right now i'll try to look for a JTAG service..
just to see my GNOTE bring back to life..
the repartition thing destroyed boot..
not even download mode can be accessed.. hard bricked..

Sad
jaycm1130 said:
yes.. were facing same problem.. i feel you..
right now i'll try to look for a JTAG service..
just to see my GNOTE bring back to life..
the repartition thing destroyed boot..
not even download mode can be accessed.. hard bricked..
Click to expand...
Click to collapse
Your your one is more complicated than mine. I can use my note now but unstable and 10GB memory loss

I.am.zahid said:
Your your one is more complicated than mine. I can use my note now but unstable and 10GB memory loss
Click to expand...
Click to collapse
my trouble began after flashing the leak version of android 4.1.2 DBT..
phone hangs and needed to reboot just like your case..
i tried to repartition to see that, if i skip the bad sectors of the internal storage.. i could see good results..
unfortunately odin hands, and after i unplug the phone.. it never turned on..
deadboot..

[Guide] Link2SD (or Apps2SD) on Galaxy Tab A (SM T-580)

Hello folks. Before going further I need to apologize. I really fighted to use Link2SD on my Galaxy tablet and I succeeded more or less. I thought that my tentative could be useful to others. So I posted this topic.
I worked a little more, and now I am convinced that I was wrong from the beginning.
The reality is that Apps2SD and Link2SD are obsolete utilities.
Forget creating a second volume on your external SD Card :
- Android/Samsung declare your SD Card as corrupted and always wants to reformat it.
- TWRP mounts the wrong partition and you have to manually unmout it and remount the good one
- The partitions need to be declared with a wrong type and this is really not clean
etc...
I suggest that you do not loose your time, forget Link2SD, and read this excellent topic:
https://www.xda-developers.com/divi...gles-fuse-replacement-will-reduce-io-overhead
My Galaxy tab A has only 11 Go available for the user. I bought a 128 Go external SD card to extend both /storage/emulated/0 and /data.
When you first install your SD Card, Android automatically mount this card as /storage/xxxx-xxxx.
This is a FAT volume extended on all your SD Card (128 GB for me).
This is fine for storing ebooks, music, video, and your backups.
But impossible for Link2SD to move your apps on this volume and put a symbolic link on the previous location, because FAT is not a UNIX file system. Link2SD (or Apps2SD) needs a second disk volume on partition 2 (/dev/block/mmcblk1p2) formatted with a UNIX file system (ext4 is fine).
Of course you need to have rooted your device. [A non rooted tablet is not better than a vulgar iPhone ]
To re-partition my SD Card I used ROEHSOFT PARTITION TOOL (SD-USB). (I tried unsuccessfully Aparted, it crashed every time I launch it). ROEHSOFT is convenient but tricky to be used by an advanced user :
- You cannot create a partition in a specific slot (for example /dev/block/mmcblk1p2): It automatically use first slot for the first partition you create, the second slot for the following partition, and so on.
- If you try to foul it, deleting a partition and recreating it in another empty space, it suddenly decides to reorganize your 4 slots. It really wants /dev/block/mmcblk1p1 to be the first partition on your SD Card, /dev/block/mmcblk1p2 the following, etc...
- You cannot create a partition at a specific offset inside an empty space.
After fighting with ROEHSOFT I finally won. I discovered too late that "fdisk" is part of BusyBox. If you know "fdisk" my advice is to use it instead of fighting with a software which pretends to be user friendly but is too limited.
OK, stop bla-bla and work.
1 - Dismount your SD Card : Parameters/Device Maintenance/Storage/Menu-Storage Parameter/Dismount
2 - Delete the only one partition
3 - For a misterious reason, my Android was not happy with his FAT volume on /dev/block/mmcblk1p1. Link2SD wants his UNIX volume on /dev/block/mmcblk1p2. So, if you use ROEHSOFT you need now to create a small dummy partition on /dev/block/mmcblk1p1. For me I created a 4 Go partition to be used by Linux Deploy. This partition needs to be declared as FAT32 (LBA) but should not be formatted as a FAT file system. EXT4 is a good choice.
4 - Create the second partition for Link2SD. I suggest not too much space for it, because you probably want a huge space for the third partion. This partition needs to be declared as FAT32 (LBA) but should be formatted with a UNIX file system. EXT4 is a good choice.
5 - Create the third partition to be used as SD extension for Android. This partition should be very large : you will store on it your music, your movies, your ebooks, and above all your backups. This partition needs to be declared as FAT32 (LBA). I formatted this partition as a EXFAT file system.
6 - Reboot. If you are lucky you will get two notifications : one saying that you have a corrupted memory card, and one saying that you are ready for media files. You will get those two notifications at each reboot.
8 - Recreate mounting scripts inside Lin2SD (or Apps2SD), and reboot.
7 - If you are a UNIX user just type "df -h" in a terminal to verify that the two partitions are mounted with correct sizes).
8 - You can look what Android think of your partitioning :
/Parameters/Device Maintenance/Storage/Menu:Storage Parameter/.
Do not try to mount the two first volumes and NEVER try to reformat them with Android. Those volumes are declared as corrupted but this is normal. Android does not expect to find a UNIX file system on a partition declared FAT32.
If one day, you forget this and ask to Android to reformat a corrupted partition you will have the terrible surprise that Android will not only erase your partition, but will erase everything and recreate one and only one big empty partition. (I guess that you keep all your backups on this SD Card, like me, so this is a really bad surprise).
Do not ask me why Android does not want his SD-Card on first partition. I have no idea. I guess that Android or Samsung reserve this partition for something else.
Do not ask why I had to declared all my partitions as FAT32 even if two of them are formatted as EXT4. I just realized that this configuration works well after fighting during a full day.
I hope that this topic will help some of you.

You really need the second partition on the SD? Or you can have only one ex4 partition that fills all the SD? (Remove the FAT and only have one ext4)

Palatosino said:
You really need the second partition on the SD? Or you can have only one ex4 partition that fills all the SD? (Remove the FAT and only have one ext4)
Click to expand...
Click to collapse
No, I tried but it doesn't work.
I found today a very interesting topic that I will try to master and hopefully wil, understand everything better :
https://www.xda-developers.com/divi...gles-fuse-replacement-will-reduce-io-overhead
Maybe I was wrong from the beginning : perhaps LinkSD and apps2SD are historic patch that are not useful anymore. Perhaps all the burden will be fixed easily just by not using those utilities anymore.
"sdcardfs" is something very new for me who is an old UNIX fellow. This seems to be a major improvement for Android.
I will update this topic when everything will be clear for me.

I didnt have this problem on android 6, but on android 7 . My phone wants to use ext4 as data partition and says its corrupted, link2sd detects this second partition normally, but my data partition fat 32 detected on phone settings and its says its ready but there is no option to mount it.
As far as i understand from this tutorial i need to make 1 fake ext4 partition say 1mb, then second partition ext4 for use with link2sd, and third partition fat32 for use as data storage ??
My phone is samsung j7 2016
So i did follow this , but now my phone wont detect fat32 and link2sd didnt detect 1 of other ext4 partitions

Looking for a definitive way to Root and use link2sd to have my SM-T580 use the SD as a primary parition for apps and data. Been researching and trying a dozen different methods already to no avail. Bonus if there's a way to roll it back easily. Am on the latest android release.
Thank you for all replies.

larpoux said:
I hope that this topic will help some of you.
Click to expand...
Click to collapse
You're my saviour, thank you ! I've been fighting on the same issue for days and didn't think about that trick to declare an ext partition as FAT32 !

I know you probably won't see this, but I just wanted to tell you how much I appreciated this guide.
I have a Galaxy Tab S3 and every since going to a custom rom, I haven't been able to get this working which was such a pain with less than 23 gb of storage. The Rom improved my performance far too much for me to change back and every guide I attempted pointed me in the wrong direction but finally, I'm able to use my 120 gb SD card which has made my tablet worth using again.
To anyone who may attempt in the future,
I'm using Android 9 + Magisk. Using the Advanced type Mount script was the only way it get it functioning but I've had no issues with linking apps and no message regarding a corrupted SD card. It can take a few minutes on boot for everything to properly load in, but the apps all update and there's no performance/loading time issues.
Thanks again!