Re: [PATCH v2 0/4] Add online file check feature

[Greg KH <greg@kroah.com>]

On Wed, Dec 02, 2015 at 07:05:27PM -0700, Gang He wrote:
> Hello Pavel,
> 
> 
> 
> >>> 
> > On Wed 2015-10-28 14:25:57, Gang He wrote:
> >> When there are errors in the ocfs2 filesystem,
> >> they are usually accompanied by the inode number which caused the error.
> >> This inode number would be the input to fixing the file.
> >> One of these options could be considered:
> >> A file in the sys filesytem which would accept inode numbers.
> >> This could be used to communication back what has to be fixed or is fixed.
> >> You could write:
> >> $# echo "CHECK <inode>" > /sys/fs/ocfs2/devname/filecheck
> >> or
> >> $# echo "FIX <inode>" > /sys/fs/ocfs2/devname/filecheck
> >> 
> > 
> > Are you sure this is reasonable interface? I mean.... sysfs is
> > supposed to be one value per file. And I don't think its suitable for
> > running commands.
> Usually, the corrupted file (inode) should be rarely encountered for OCFS2 file system, then
> lots of commands are executed via this interface with high performance is not expected by us.
> Second, after online file check is added, we also plan to add a mount option "error=fix", that means
> the file system can fix these errors automatically without a manual command triggering.

It's not a "performance" issue, it's a "sysfs files only have one value"
type thing.  Have two files, "inode_fix" and "inode_check" and then just
write the inode into them, no need to have a "verb <inode>" type parser.

thanks,

greg k-h