On Wed, 31 Dec 2008 17:19:44 +0200 Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: > Andrew Morton wrote: > > On Tue, 16 Dec 2008 17:33:48 +0200 > > Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: > > > >> We need a mechanism to prepare the file system (mkfs). > >> I chose to implement that by means of a couple of > >> mount-options. Because there is no user-mode API for committing > >> OSD commands. And also, all this stuff is highly internal to > >> the file system itself. > >> > >> - Added two mount options mkfs=0/1,format=capacity_in_meg, so mkfs/format > >> can be executed by kernel code just before mount. An mkexofs utility > >> can now be implemented by means of a script that mounts and unmount the > >> file system with proper options. > > > > Doing mkfs in-kernel is unusual. I don't think the above description > > sufficiently helps the uninitiated understand why mkfs cannot be done > > in userspace as usual. Please flesh it out a bit. > > There are a few main reasons. > - There is no user-mode API for initiating OSD commands. Such a subsystem > would be hundredfold bigger then the mkfs code submitted. I think it would be > hard and stupid to maintain a complex user-mode API just for creating > a couple of objects and writing a couple of on disk structures. > - I intend to refactor the code further to make use of more super.c services, > so to make this addition even smaller. Also future direction of raid over > multiple objects will make even more kernel infrastructure needed which > will need even more user-mode code duplication. > - I anticipate problems that are not yet addressed in this body of work > but will be in the future, mainly that a single OSD-target (lun) can > be shared by lots of FSs, and a single FS can span many OSD-targets. > Some central management is much easier to do in Kernel. OK. Please add the above info to the changelog for that patch. > > > > What are the dependencies for this filesystem code? I assume that it > > depends on various block- and scsi-level patches? Which ones, and > > what is their status, and is this code even compileable without them? > > > > This OSD-based file system is dependent on the open-osd initiator library > code that I've submitted for inclusion for 2.6.29. It has been sitting > in linux-next for a while now, and has not been receiving any comments > for the last two updated patchsets I've sent to scsi-misc/lkml. However > it has not yet been submitted into Jame's scsi-misc git tree, and James > is the ultimate maintainer that should submit this work. I hope it will > still be submitted into 2.6.29, as this code is totally self sufficient > and does not endangers or changes any other Kernel subsystems. > (All the needed ground work was already submitted to Linus since 2.6.26) > So why should it not? > > Once the open-osd initiator library is accepted this file system > could be accepted. I was hoping as a 2.6.30 time frame. (One Kernel > after the open-osd library) > > > Thanks. > > Thank you dear Andrew for your most valuable input. > > I will constify all the const needed code. will fix the global name space > litter, will inline the macros and lower case the inlines. Will remove > the typedefs. > > I will reply to individual patches, I have a couple of questions. But > all your comments are right and I will take care of them. > > When, if, all is fixed, through which tree/maintainer can exofs be submitted? I can merge them. Or you can run a git tree of your own, add it to linux-next and ask Linus to pull it at the appropriate time. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
