Re: [PATCH] ext4: Convert uninitialized extent to initialized extent in case of file system full

Aneesh Kumar K.V
2008-02-22T15:07:32Z

Test results for the patch.

mmaptest simply maps a range and write to it.
The length of the extent indicate whether it is initialized or not.

There is no space in the file system for another block.
So the uninitialized extent have to be converted to initialized extent.

root@qemu-image:/ext4# /root/mmaptest testfile 0 100
mmaping 0 to 100
[kvaneesh@llm59 linux-2.6.25-rc2]$ ~/ext4migrate --display /home/kvaneesh/test-images/ext3.img testfile
extent: block=0-3 len=4 start=1153 start_hi=0
extent: block=4-32807 len=32804 start=1157 start_hi=0

root@qemu-image:/ext4# dd if=/root/a.c of=testfile seek=6 bs=4096 conv=notrunc
[kvaneesh@llm59 linux-2.6.25-rc2]$ ~/ext4migrate --display /home/kvaneesh/test-images/ext3.img testfile
extent: block=0-3 len=4 start=1153 start_hi=0
extent: block=4-32791 len=32788 start=1157 start_hi=0
extent: block=24-24 len=1 start=1177 start_hi=0
extent: block=25-32807 len=32783 start=1178 start_hi=0

root@qemu-image:/ext4# dd if=/root/a.c of=testfile seek=8 bs=4096 conv=notrunc
[kvaneesh@llm59 linux-2.6.25-rc2]$ ~/ext4migrate --display /home/kvaneesh/test-images/ext3.img testfile
extent: block=0-3 len=4 start=1153 start_hi=0
extent: block=4-32791 len=32788 start=1157 start_hi=0
extent: block=24-24 len=1 start=1177 start_hi=0
extent: block=25-39 len=15 start=1178 start_hi=0

root@qemu-image:/ext4# /root/mmaptest testfile 4096 5000
mmaping 4096 to 5000
[kvaneesh@llm59 linux-2.6.25-rc2]$ ~/ext4migrate --display /home/kvaneesh/test-images/ext3.img testfile
extent: block=0-3 len=4 start=1153 start_hi=0
extent: block=4-23 len=20 start=1157 start_hi=0
extent: block=24-24 len=1 start=1177 start_hi=0
extent: block=25-39 len=15 start=1178 start_hi=0