Need help reclaiming full SSD space from old Windows dual-boot (No USB drive available)

Issues & Assistance
1

Hi everyone,

I recently removed Windows from my PC and I am now running CachyOS as my single operating system. Previously, I had a dual-boot setup.

My goal is to make CachyOS use 100% of my SSD (or at least reclaim all the space left behind by Windows for my Linux files/games), but I am having trouble doing so from within the running system.

Here are my constraints and what I’ve found so far:

1. I do NOT have a USB flash drive (pen drive) at home, so I cannot do a clean reinstall from a Live ISO. I need to fix this directly from my current CachyOS installation.

2. I tried unmounting a FAT32 partition to format it, but the system says it’s busy (I assume it’s my current EFI boot partition, so I didn’t force it).

3. I can still see the old Windows partition space (what used to be the C: drive).

Since CachyOS uses Btrfs by default, I would like to know the safest way to either delete the old Windows partition and expand my current CachyOS partition online, or properly format that leftover space to Btrfs/Ext4 and mount it automatically for my games/files

Thanks in advance for the help!

2

can you provide from konsole or TTY ( Ctrl + Alt + F2 to F7 )

sudo parted -l
3

I’m on Android so I gonna send the screenshot

4

1000609292
10006092921920×1442 328 KB

Here anyways

5

i will add

sudo lsblk -fs
6

Here a minute

1000609294
10006092941920×2557 577 KB

7

Done already

8

What I do now?

9

so for better understanding
your boot Efi cachyos is nvme0n1p4 ( 1 disk nvme - partition 4 )
your partition root ( and all others including /home is on nvme0n1p5 ( 1 disk nvme - partition 4 )

so partitions 1 and 7 can be reuse.

be careful btrfs is working on sub volume , not partition
this will not be easy :

  1. you should reformat nvme0n1p1 and nvme0n1p7 in btrfs/ext4 , but be careful in choose name mountpoint , that will create new UUID , note them
sudo lsblk -fs

  1. the live ISO USB is very useful in case of trouble / recover

  2. check state from your /etc/fstab

sudo cat /etc/fstab
  1. we may after add theses new UUID to /etc/fstab
10

Also here

1000609297
10006092971920×2557 862 KB

11

so use gparted for that
launch gparted , format each with each mountpoint ( exemple /game or /data ) in btrfs

12

Done, I already named to /data /game

13

can you report

sudo lsblk -fs

for the moment you cant use it , because this is not in your /etc/fstab

for maintenance

# Scrub the BTRFS filesystem
btrfs scrub start /
 
# Balance the BTRFS filesystem
btrfs balance start /
14

This worked btw thanks you, I using they as a data or a management

Here my configs

I managed to solve it.

I created two separate Btrfs partitions and mounted them through “/etc/fstab”.

My layout is:

- “/dev/nvme0n1p5” → Root (“/”)

- “/dev/nvme0n1p1” → “/data”

- “/dev/nvme0n1p7” → “/documents”

I created the mount points:

sudo mkdir -p /data

sudo mkdir -p /documents

Then I added these entries to “/etc/fstab”:

UUID=you UUID /data btrfs defaults 0 0

UUID=your UUUD /documents btrfs defaults 0 0

Finally, I mounted everything with:

sudo mount -a

After rebooting, both partitions are mounted automatically and work as expected.

15

I’m bet the creator fix this on next updates

16

There does not seem to be anything for a ‘creator’ to ‘fix’?

You deleted a partition and added partition(s) in its place and wrote lines related to that in your fstab.

This is simply normal use of those things.

17

No, I’m just a starter on Linux community, You know I make a lot of mistakes.

18

No worries.

There is also always the possibility that I missed or misunderstood something. :slight_smile: