mkfs.f2fs: wipe other FS magics given -f
This patch fixes the below stale magic info.
$ mkfs.btrfs -f test.img
btrfs-progs v5.10.1
See http://btrfs.wiki.kernel.org for more information.
Label: (null)
UUID: 941d2db7-3ece-4090-8b22-c4ea548b5dae
Node size: 16384
Sector size: 4096
Filesystem size: 1.00GiB
Block group profiles:
Data: single 8.00MiB
Metadata: DUP 51.19MiB
System: DUP 8.00MiB
SSD detected: no
Incompat features: extref, skinny-metadata
Runtime features:
Checksum: crc32c
Number of devices: 1
Devices:
ID SIZE PATH
1 1.00GiB test.img
$ hexdump -s 0x10000 -n 128 -C test.img
00010000 81 29 94 0a 00 00 00 00 00 00 00 00 00 00 00 00 |.)..............|
00010010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00010020 94 1d 2d b7 3e ce 40 90 8b 22 c4 ea 54 8b 5d ae |..-.>.@.."..T.].|
00010030 00 00 01 00 00 00 00 00 01 00 00 00 00 00 00 00 |................|
00010040 5f 42 48 52 66 53 5f 4d 05 00 00 00 00 00 00 00 |_BHRfS_M........|
00010050 00 40 d2 01 00 00 00 00 00 40 50 01 00 00 00 00 |.@.......@P.....|
00010060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00010070 00 00 00 40 00 00 00 00 00 00 02 00 00 00 00 00 |...@............|
00010080
$ mkfs.f2fs -t 0 -f test.img
F2FS-tools: mkfs.f2fs Ver: 1.14.0 (2020-12-28)
Info: Disable heap-based policy
Info: Debug level = 0
Info: Trim is disabled
Info: Segments per section = 1
Info: Sections per zone = 1
Info: sector size = 512
Info: total sectors = 2097152 (1024 MB)
Info: zone aligned segment0 blkaddr: 512
Info: format version with
"Linux version 5.10.46-4rodete1-amd64 (glinux-team@google.com) (gcc-10 (Debian 10.2.1-6+build2) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2) #1 SMP Debian 5.10.46-4rodete1 (2021-08-20)"
Info: Overprovision ratio = 6.360%
Info: Overprovision segments = 68 (GC reserved = 39)
Info: format successful
$hexdump -s 0x10000 -n 128 -C test.img
00010000 c2 8a c8 26 00 00 00 00 00 00 00 00 00 00 00 00 |...&............|
00010010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00010020 92 ab 3f c6 b7 82 49 5e 93 23 e8 c9 e9 45 7d ac |..?...I^.#...E}.|
00010030 00 00 01 00 00 00 00 00 01 00 00 00 00 00 00 00 |................|
00010040 5f 42 48 52 66 53 5f 4d 05 00 00 00 00 00 00 00 |_BHRfS_M........|
00010050 00 40 d2 01 00 00 00 00 00 40 50 01 00 00 00 00 |.@.......@P.....|
00010060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00010070 00 00 00 40 00 00 00 00 00 00 02 00 00 00 00 00 |...@............|
00010080
--- After this patch ---
$ mkfs.f2fs -t 0 -f test.img
F2FS-tools: mkfs.f2fs Ver: 1.14.0 (2020-12-28)
Info: Disable heap-based policy
Info: Debug level = 0
Info: Trim is disabled
test.img appears to contain an existing filesystem (btrfs).
Info: Segments per section = 1
Info: Sections per zone = 1
Info: sector size = 512
Info: total sectors = 2097152 (1024 MB)
Info: zone aligned segment0 blkaddr: 512
Info: format version with
"Linux version 5.10.46-4rodete1-amd64 (glinux-team@google.com) (gcc-10 (Debian 10.2.1-6+build2) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2) #1 SMP Debian 5.10.46-4rodete1 (2021-08-20)"
Info: Overprovision ratio = 6.360%
Info: Overprovision segments = 68 (GC reserved = 39)
Info: format successful
$ hexdump -s 0x10000 -n 128 -C test.img
00010000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00010080
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
4 files changed
