Re: Quota mods needed for journaled quota
hi Stephen, On Oct 26, 11:00am, Stephen C. Tweedie wrote: > Subject: Re: Quota mods needed for journaled quota > ... > > This would allow ext3 to do that which it needs to do differently > > at Q_QUOTAON and would also allow Jan's changes to work in such > > a way that both the current form of dquot structure and his new > > version of dquots could be used together > > Adding the init_quota hook would do that, as the filesystem will be > able to install its own dq_ops methods during the init so we get the > flexibility you are asking for anyway. > Hmmm ... I'm not so sure. In order to have the flexibility of filesystem-specific dquot formats, the struct dquot would need to become more like struct inode/super_block, i.e. not hardcoding the ondisk structure into the incore structure (using a union and a generic pointer, as inode/super_block do). The DQUOT_SYNC mechanism would need to be able to be overridden per-filesystem also. It isn't really as cut-and-dried as "per- filesystem" either, because an ext2/3 filesystem might make use of either the original dquot format or Jan's newer format, either at mount time or even after doing a quota_off & quota_on with a new quota file format (that would be quite clean). But I've sidetracked completely from what you were originally talking about now, which had nothing to do with a different ondisk format at all. cheers. -- Nathan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: Quota mods needed for journaled quota
Hi, On Thu, Oct 26, 2000 at 12:53:00PM -0400, Nathan Scott wrote: > > The addition of an "init_quota" method to the super_operations struct, > > with quota_on calling this and defaulting to installing the default > > quota_ops if the method is NULL, ought to be sufficient to let ext3 > > get quotas right in all cases as far as I can see. > > It might also/alternatively be generally useful to allow a > filesystem-specific implementation of quotactl itself - through > an additional member in the dquot_operations set of functions? I'm not sure how useful that addition would be --- for quota_on and quota_off, at least, the setting up of the dquot structures around the superblock or their destruction after quota_off can probably stay as common code, with calls into the filesystem for init_quota (and perhaps destroy_quota?) at the appropriate places. > This would allow ext3 to do that which it needs to do differently > at Q_QUOTAON and would also allow Jan's changes to work in such > a way that both the current form of dquot structure and his new > version of dquots could be used together Adding the init_quota hook would do that, as the filesystem will be able to install its own dq_ops methods during the init so we get the flexibility you are asking for anyway. Cheers, Stephen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: Quota mods needed for journaled quota
hi Stephen, On Oct 26, 11:00am, Stephen C. Tweedie wrote: Subject: Re: Quota mods needed for journaled quota ... This would allow ext3 to do that which it needs to do differently at Q_QUOTAON and would also allow Jan's changes to work in such a way that both the current form of dquot structure and his new version of dquots could be used together Adding the init_quota hook would do that, as the filesystem will be able to install its own dq_ops methods during the init so we get the flexibility you are asking for anyway. Hmmm ... I'm not so sure. In order to have the flexibility of filesystem-specific dquot formats, the struct dquot would need to become more like struct inode/super_block, i.e. not hardcoding the ondisk structure into the incore structure (using a union and a generic pointer, as inode/super_block do). The DQUOT_SYNC mechanism would need to be able to be overridden per-filesystem also. It isn't really as cut-and-dried as "per- filesystem" either, because an ext2/3 filesystem might make use of either the original dquot format or Jan's newer format, either at mount time or even after doing a quota_off quota_on with a new quota file format (that would be quite clean). But I've sidetracked completely from what you were originally talking about now, which had nothing to do with a different ondisk format at all. cheers. -- Nathan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: Quota mods needed for journaled quota
Hi, On Thu, Oct 26, 2000 at 12:53:00PM -0400, Nathan Scott wrote: The addition of an "init_quota" method to the super_operations struct, with quota_on calling this and defaulting to installing the default quota_ops if the method is NULL, ought to be sufficient to let ext3 get quotas right in all cases as far as I can see. It might also/alternatively be generally useful to allow a filesystem-specific implementation of quotactl itself - through an additional member in the dquot_operations set of functions? I'm not sure how useful that addition would be --- for quota_on and quota_off, at least, the setting up of the dquot structures around the superblock or their destruction after quota_off can probably stay as common code, with calls into the filesystem for init_quota (and perhaps destroy_quota?) at the appropriate places. This would allow ext3 to do that which it needs to do differently at Q_QUOTAON and would also allow Jan's changes to work in such a way that both the current form of dquot structure and his new version of dquots could be used together Adding the init_quota hook would do that, as the filesystem will be able to install its own dq_ops methods during the init so we get the flexibility you are asking for anyway. Cheers, Stephen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/