I created a zeroed file with dd and attempted to mount it with:
mount -o loop /sdcard/test.img /data/test
and
losetup /dev/block/loop0 /sdcard/test.img
However, no loopback devices are displayed when I invoke mount. Can anyone clue me in? Feel like i'm missing something basic. By the way, I am running these commands from Saurik's busybox with the losetup /dev/block/loop fix.
p.s. I'd ask on the G1 hackers mailing list, but it's gone a bit bonkers in the past few days.
I'm not sure, but doesn't the image file you're trying to mount have to contain an actual file system?
Yea, I subsequently created a filesystem for it with mke2fs (which is mysteriously missing from busybox for android?). Still no go. Same when I tried to mount other partition-in-a-files like the module.cramfs or recovery.img
If I try to losetup the loop device then mount that, it returns error:
mount: mounting /dev/block/loop0 on /data/test failed: No such device
If I try to mount directly with -o loop, it returns:
mount: cannot setup loop device: No such file or directory
And yet Saurik seems to have been able to loop mount fine. Perhaps it is because I am testing on the qemu instead of hardware?
That might be it. You might try busybox's mount also.
But yeah, It definitely does work on the phone at least.
I've been trying to figure out how to load debian on the emulator, but I can't get the ext2 image mounted. I had to recompile the kernel first so support loadable modules, but even after that, it would not work (can't remember the specific error). Has anyone gotten an ext2 file system mounted on the emulator successfully?
The reason I'm doing this is so I can do native compiles, without actually having to do it on the phone. It has advantages in that I can crank up the clock speed and the RAM.
So I was able to mount loopback just fine on the actual hardware, but i'm having trouble getting it to run from the init.rc file. This is what i'm typing at the shell (it works):
(after insmod ext2.ko)
mount -o loop,noatime,nodiratime,nosuid,nodev -t ext2 /sdcard/loopy/app.img /data/app
It works fine and i'm able to install and run apks from the sdcard (/dev/block/loop2 on /data/app type ext2). Of course this is no good unless it can be mounted before the launcher starts (or it won't see any of our apks). The syntax for init mounting is different from sh, so I tried this (this is in /data/init.rc btw):
on userdata
#mount loopback file from sdcard
insmod /system/modules/2.6.25-01843-gfea26b0/kernel/fs/ext2/ext2.ko
mount ext2 /sdcard/loopy/app.img /data/app noatime nodiratime nosuid nodev loop
I know the script is being run since the ext2.ko module is getting installed. But the mount command isn't being executed. Can anyone shine a light on this? I'm not very familiar with the init daemon.
jashsu said:
So I was able to mount loopback just fine on the actual hardware, but i'm having trouble getting it to run from the init.rc file. This is what i'm typing at the shell (it works):
(after insmod ext2.ko)
mount -o loop,noatime,nodiratime,nosuid,nodev -t ext2 /sdcard/loopy/app.img /data/app
It works fine and i'm able to install and run apks from the sdcard (/dev/block/loop2 on /data/app type ext2). Of course this is no good unless it can be mounted before the launcher starts (or it won't see any of our apks). The syntax for init mounting is different from sh, so I tried this (this is in /data/init.rc btw):
on userdata
#mount loopback file from sdcard
insmod /system/modules/2.6.25-01843-gfea26b0/kernel/fs/ext2/ext2.ko
mount ext2 /sdcard/loopy/app.img /data/app noatime nodiratime nosuid nodev loop
I know the script is being run since the ext2.ko module is getting installed. But the mount command isn't being executed. Can anyone shine a light on this? I'm not very familiar with the init daemon.
Click to expand...
Click to collapse
Try
mount ext2 [email protected]/sdcard/loop/app.img /data/app noatime nodiratime nosuid nodev
JesusFreke said:
Try
mount ext2 [email protected]/sdcard/loop/app.img /data/app noatime nodiratime nosuid nodev
Click to expand...
Click to collapse
Tried that one earlier too. No love.
jashsu said:
Tried that one earlier too. No love.
Click to expand...
Click to collapse
I betcha the sdcard hasn't been mounted yet.
Is there anything in dmesg that looks relevant? Or maybe logcat?
Try temporarily moving the image file to /data, and see if you can get it to mount. That should verify that it has something to do with it being on the sdcard
JesusFreke said:
I betcha the sdcard hasn't been mounted yet.
Is there anything in dmesg that looks relevant? Or maybe logcat?
Click to expand...
Click to collapse
Agh! You're right. The mount daemon runs at line 192, in the services section. Long after the /data/init.rc is parsed.
service mountd /system/bin/mountd
socket mountd stream 0660 root mount
Any way around this short of manually mounting the sdcard in the /data/init.rc?
Edit: dmesg bingo:
<3>[ 1.920368] init: unable to mount [email protected]/sdcard/loopy/app.img to /data/app
as ext2
<6>[ 1.921498] yaffs: dev is 32505860 name is "mtdblock4"
<6>[ 1.922016] yaffs: passed flags ""
<4>[ 1.922322] yaffs: Attempting MTD mount on 31.4, "mtdblock4"
<4>[ 1.927204] yaffs: restored from checkpoint
<4>[ 1.927845] yaffs_read_super: isCheckpointed 1
<3>[ 1.960002] init: unable to mount /system/xbin.cramfs to /system/xbin as c
ramfs
<3>[ 1.965221] init: service 'console' requires console
<4>[ 2.161895] mmc_sd_init_card: Delay 250 ms
<4>[ 2.522535] mmc1: host does not support reading read-only switch. assuming
write-enable.
<6>[ 2.523359] mmc1: new SDHC card at address cd4e
On a side note, it looks like the mount action for xbin.cramfs in the main init.rc is failing because it's redundant with an earlier mount in /system/init.rc. I'm guessing this is a vestige of development on cramfs loopback mounting (mentioned here by Saurik).
6) at Jesus Freke's suggestion, setup /system/xbin (and later /system/modules) to mount from a compressed image
Click to expand...
Click to collapse
Yeah, I had left in an extra mount for xbin.cramfs in the base init.rc. I believe that's fixed in v1.3. I'll check again and make sure
So I gather the reason for wanting to mount a loopback device is to be able to create an ext2 fs as a file on the sdcard fat fs instead of creating 2 separate parittions on the sdcard , one for fat and one for ext2?
If this can be done, this would be a much better solution for getting apps to run on the sdcard than the previous hack which requires creating an ext2 partition on the sdcard.
Yeah that was what I was looking into. However as noted above, the I couldn't mount the image on the sdcard because the point at which /data/init.rc gets parsed occurs before the sdcard service starts up. The partition method doesn't have this problem because it creates a node for paritition #2 in the init.rc
jashsu said:
Yeah that was what I was looking into. However as noted above, the I couldn't mount the image on the sdcard because the point at which /data/init.rc gets parsed occurs before the sdcard service starts up. The partition method doesn't have this problem because it creates a node for paritition #2 in the init.rc
Click to expand...
Click to collapse
so u can't mount the sdcard in /data/init.rc?
dwang said:
so u can't mount the sdcard in /data/init.rc?
Click to expand...
Click to collapse
Not sure, I didn't try mounting partition #1. You could give it a shot by using mknod in /data/init.rc like the parted sdcard method. The sdcard service might not like that the card has already been mounted though.
There are two major reasons I abandoned this concept. The first is I didn't want to figure out how to get permission to mount /sdcard (since / is ro). The second is that making the sdcard available as a usb mass storage device makes it exclusively unaccessible from Android. I suppose that might not be so bad if you are only offloading /data/app, as long as you don't try to execute any new apps while your mass storage connection is going. It's non-ideal.
jashsu said:
Not sure, I didn't try mounting partition #1. You could give it a shot by using mknod in /data/init.rc like the parted sdcard method. The sdcard service might not like that the card has already been mounted though.
There are two major reasons I abandoned this concept. The first is I didn't want to figure out how to get permission to mount /sdcard (since / is ro). The second is that making the sdcard available as a usb mass storage device makes it exclusively unaccessible from Android. I suppose that might not be so bad if you are only offloading /data/app, as long as you don't try to execute any new apps while your mass storage connection is going. It's non-ideal.
Click to expand...
Click to collapse
I don't think the 2nd reason is that big of a deal. If google is planning on implementing the file based method for apps on the sdcard, they could just block access to apps when the sdcard is mounted to a pc. Its a lot better than the alternative of having to create a 2nd ext2 partition on the sdcard. Of course google should have really solved this issue before the g1 came out.
Anyways, I don't see /data/init.rc on my jf rc 1.2 g1. I only see /init.rc and /system/init.rc. Is /data/init.rc something that you created just for the purpose of mounting the file.
dwang said:
I don't think the 2nd reason is that big of a deal. If google is planning on implementing the file based method for apps on the sdcard, they could just block access to apps when the sdcard is mounted to a pc. Its a lot better than the alternative of having to create a 2nd ext2 partition on the sdcard. Of course google should have really solved this issue before the g1 came out.
Anyways, I don't see /data/init.rc on my jf rc 1.2 g1. I only see /init.rc and /system/init.rc. Is /data/init.rc something that you created just for the purpose of mounting the file.
Click to expand...
Click to collapse
Yeah it's referenced in /init.rc Easier to use since unlike /system/init.rc, it's not in a ro folder. You could use /system/init.rc too. Either way really.
jashsu said:
Yeah it's referenced in /init.rc Easier to use since unlike /system/init.rc, it's not in a ro folder. You could use /system/init.rc too. Either way really.
Click to expand...
Click to collapse
Ok.. I'll probably just stick with partitioning the sdcard into fat and ext2. Its working well for me and there really isn't a whole lot of advantages having the ext2 as a file on the fat partition.
I have 41 apps installed on the sdcard now (including some huge games like bonzai blast and brain genius deluxe) and I still have 59 megs of free internal storage. I think everybody that has a rooted g1 should put apps to the sdcard.
My captivate is already rooted, i use the Astro app to edit files and now im trying to edit the /system/etc/gps.conf, but when i try to save...does not save...i notice this file is read only rights. How can i edit that and save it???
to mount /system as read write, you need to be rooted (obviously) and open up an adb shell.
mount -o rw /dev/block/stl9 /system
depending on what kernel you're running and what filesystem /system is mounted as you *may* need to specify the filesystem ("-t vfat" for rfs, "-t ext4" for voodoo) but I've never had to before.
Attempting to partition sd card with ext4 -a process I completed multiple times successfully on a Nexus One, the process appeared to complete but now the phone will not mount the sd card. I've tried a wipe/reset, to no avail. I can still access and partition the sd card through adb, but the phone cannot mount it to format/partition, restore from recovery, partition sd-card from within ClockWork Recovery, nothing. I've re-partitioned the sd card through adb, which indicated a successful completion, but the phone still refuses to mount the sd card. If this weren't a Nexus S with it's cursed internal sd-card I would simply swap out the sd card with another or format it externally like all the google topics I pull up on the subject suggest.
Is this fixable or has the fused sd-card scenario become a liability?
Common Error messages:
Can't mount /sdcard
Can't mount /sdcard/.android_secure
Phone: Nexus S (US, T-Mobile, manufactured Dec. '10)
Recovery Img: ClockworkMod Recovery 3.0.2.4
Rom: CM 7.0.3 (now wiped, cannot put back on since sd card won't mount)
fstab:
/dev/block/mtdblock4 /cache yaffs2 rw
/dev/block/platform/s3c-sdhci.0/by-name/userdata /data ext4 rw
/dev/block/platform/s3c-sdhci.0/by-name/system /system ext4 rw
/dev/block/platform/s3c-sdhci.0/by-name/media /sdcard vfat rw
Can mount everything except the last one, /sdcard.
I've tried all the recommended procedures garnered from the first 10 or so pages in google, xda, cyanogem forum, etc:
Restore from nandroid: Not possible, can't mount the SD,
Wipe/Reset: can't wipe /media as sd card won't mount,
partition sd card from within Clockwork: indicates success but does nothing,
format from within clockwork: unable to mount,
repartition using adb: works, parted can see them, I can move files to from, but the phone will not mount,
clearing fstab: no effect,
Fastboot works, but I don't have the proper images. ADB works, as do the installed utilities. Have not tried ODIN as again, I don't have the proper images. Should I attempt to compile my own images from source?
Update: SOLVED, Microsoft Windows. To whom it may concern: I was able to mount the /dev/block/platform/s3c-sdhci.0/by-name/media from two different laptops running OSX and Fedora/Ubuntu then successfully been able to partition them with fat32 as the ClockworkMod (and maybe Cyanogen?) expect with 0 progress. Then I pulled out an old Windows machine, installed the JDK/ADK's +tools and performed the same procedure and that time it worked. I'm uncertain as to what particular quality a 'genuine' Windows formatting provides, but either this phone or the particular software combination I'm running require it. I was able to mount & re-partition the /sdcard in Clockwork, then manually remove rebuild them and upgrade to ext4 using tune2fs as usual. In the interim for work and such, I had to find a surrogate (for the SIM) and could only find and old k750i (which still had a full charge and worked flawlessly all day, btw). Wow phones used to be small.
I think I was missing something about the way ClockworkMod handles fstab, because everytime I would modify it specifically to the specs I passed to parted while creating the partitions with mkpartfs, it would either ignore or overwrite them. So be careful messing with the sd-card, the S's aren't like the One's in the sense that if you screw it (the sd-card) up or it goes bad you can't just take it out and format it in another machine/phone, you have to appeal to ClockworkMod. ODIN $ucks by the way, I found fastboot to be much more effective.
If you format the sd partition ext4, then you should change the fstab too.
from
Code:
/dev/block/platform/s3c-sdhci.0/by-name/media /sdcard vfat rw
to from
Code:
/dev/block/platform/s3c-sdhci.0/by-name/media /sdcard ext4 rw
or from
Code:
/dev/block/platform/s3c-sdhci.0/by-name/media /sdcard auto rw
The 2nd last entry there is the file system type.
Likely, this would have solved your problem.
Of course, I don't know, whether the recovery has the vfat type in fstab. You might have to change it there too. On my linux box auto works very well in fstab.
Of course, if you partition your sd partition ext4, you won't be able to use it as usb memory from windows. (At least I am pretty sure you can't, haven't tried)
Well of course I couldn't let it die, I went back and started tinkering again now that I have a way back. I can't change the fstab it seems, whatever I change it to gets over written everytime either Clockwork or the Rom starts. It's weird, I know I'm missing something and I don't know much about CWMod. (had Amon_Ra on the N1, which had the nifty fsupgrade script)
The 2nd last entry there is the file system type.
Likely, this would have solved your problem.
Click to expand...
Click to collapse
I'm quite familiar with unix style fs and fstab, it's the stubbornness I'm not used to. I'm also spoiled by vi and nano. CW has some nice scripts built in as well though.
Hi floks,
I have a oneplus X phone (Onyx) with the weirdest problem with AOSP 8.1 (this rom). I am trying to mount my partitioned external SDCard (ext2 primary partition) in /data/sd to be able to move some app data to my card and free up internal space. Mounting works ok from adb ("su"+"mount -o bind /dev/block/mmcblk1p1 /data/sd") but doesn't work from terminal. I used Magisk to root my phone. I tried other methods such as fbind magisk module and all kind of apps like link2SD, App2SD, none managed to mount my partition from the phone. Mounting from the phone is mandatory to be able to mount at boot so my apps always work.
Can someone help me with that issue ? I'm a bit lost, searched a lot around but couldn't find anything. Maybe it's kernel related, or systemless root, or the way the rom is built. Note that android sees my partition and can mount it by itself on other mount points (unmounting it before mounting doesn't help)
This is a very annoying issue but I have not found any thread about it.
I'm trying to upgrade my external/removable sdcard for an android 6 device.
The new sdcard gets mounted to /mnt/media_rw/XXXX-XXXX (i.e. not 0123-4567), so no app works as files can't be found.
The linux way (ln) wont work. Simply creating /mnt/media/0123-4567 causes bad bootloop on my device. This suggests that FolderMount app or Magisk modules such as fbind are a bad idea. selinux is enforcing.
It appears that Android assigns different mount points are to different sdcards and the first sdcard always gets 0123-4567. It that's right, Android probably stores sdcards' identifiers so as to know which mount point to use at boot time. So, deleting the identifiers database would probably mean that the next card inserted would get 0123-4567 as mount point.
I have looked at the data of com.android.externalstorage, but there is nothing there. I don't see other obvious candidate apps.
Where is this ext sdcard data stored?
I was wrong. Android sets mount points matching sdcard uuid
How to change vfat partition UUID?
How do I change the UUID of a vfat partition? For ext2 / ext3 / ext4, this is done with a simple: tune2fs -U <new-uuid> /dev/<partition> Is there a similar command for vfat partitions?
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