I tried to format a micro‐SD card to ext4 and put that in my FP2, but Open doesn’t seem to recognise it, AFAICT, but TWRP reads it fine (and AFAICT / is already ext3 or 4, so FPOSO should be able to read the fs…?).
Anyway. Which file systems are supported under FP Open?
Afaik the FS type for the SD card is specified in fstab. The OP of the closed topic commented on that here:
It isn’t clear whether you’ll need more changes, and whether persistent changes can be made after compilation, but maybe someone else can comment on that.
Ah, nice. I was thinking I’d go looking for an fstab (I’m a long time (Gentoo→Arch) Linux user), and it seems I’ve now at least made it readable, even if FPOSO won’t write to it. But I guess that’s an easily solved permissions issue.
Anyway, that tells me how to fix my own itch, but doesn’t answer the question I was setting out to find an answer for:
So ext* (ext2, ext3, ext4) and vfat are supported out of the box. … Now I wonder whether the kernel itself has support for more filesystems and just the tools aren’t there. There’s not /proc/config{,.gz} file to snoop in, and lsmod doesn’t seem to actually list loaded kernel modules…
Well, if you want to know which filesystems are supported by one Linux Kernel you have to simply cat the ‘filesystems’ file in /proc, this is the result I get on my FP OpenOS:
I’m not sure about that, but I think you’ll have to modify the fstab.qcom inside /boot, or your changes won’t survive a reboot. You’ll have to do this every time you update your phone (-> monthly ;))
Here is a nice tool to do this (however I didn’t yet have the time to try it ;))
You can - as described in README - get the boot.img from your phone, but the easier way is getting it from the update-package (should be inside the manual-versions from here).
I think I posted the contents of fstab.qcom elsewhere, but FTR, here is an example from FPOOS 16.10:
# Android fstab file.
# The filesystem that contains the filesystem checker binary (typically /system) cannot
# specify MF_CHECK, and must come before any filesystems that do specify MF_CHECK
#TODO: Add 'check' as fs_mgr_flags with data partition.
# Currently we dont have e2fsck compiled. So fs check would failed.
#<src> <mnt_point> <type> <mnt_flags and options> <fs_mgr_flags>
/dev/block/platform/msm_sdcc.1/by-name/system /system ext4 ro,barrier=1,discard wait
/dev/block/platform/msm_sdcc.1/by-name/userdata /data ext4 nosuid,nodev,barrier=1,noauto_da_alloc,discard wait,check,encryptable=footer
/devices/msm_sdcc.2/mmc_host /storage/sdcard1 vfat nosuid,nodev wait,voldmanaged=sdcard1:auto,noemulatedsd
/devices/platform/xhci-hcd/usb* /storage/usbotg vfat nosuid,nodev wait,voldmanaged=usbotg:auto
So I think it’s pretty much self-explanatory.
[And this is - by the way - the reason why no other filesystems are supported for SD-Card and USB-OTG, I don’t know any way to specify to alternative filesystems in fstab, do you?]
exFAT: FPOOS doesn’t support exFAT, because they would have to pay licence fee to Microsoft. So exFAT is no “fair” filesystem.
