Hey Sam,
> Actually pvfs2_xattr_get_default calls pvfs2_inode_getxattr which
> returns the size of the extended attribute.
Oh right.. Only set_default returns 0 or -ve..
Good..
>
> > - This looks incorrect:
> >
> > if(ret >= 0)
> > + {
> > + return put_user(val, (int __user *)arg);
> > + }
>
> I pulled that out of the ext3 ioctl code. Seems to work. Without it
> lsattr gives bad results.
What I meant was not the put_user() part :)
What I meant was it may be incorrect to put the value of "val" to user-space
due to
> > Flags:
> > PVFS_IMMUTABLE_FL != FS_IMMUTABLE_FL
> > PVFS_APPEND_FL != FS_APPEND_FL
> > PVFS_NOATIME_FL != FS_NOATIME_FL
the above inequalities.. hence "Val" needs to be converted before the
put_user().
>
> Yeah, why don't they?
I did not realize we were going to integrate them with FS_IOC_SETFLAGS...
at that time :)
If the values used by the kernel are unused for our flags, by all
means they can be changed.
Has there been any release for folks making use of the current value
of flags since we store them on disk..? :(
>
> >
> > Before the put_user(), you should convert val from a PVFS_*_FL to a
> > FS_*_FL flag I think.
> > ELse the chattr utility won't understand these flags..
This is what I hinted at above. Not the put_user() being a mistake..
> > - if(arg & FS_APPEND_FL)
> > + {
> > + val |= PVFS_IMMUTABLE_FL; <--- PVFS_APPEND_FL
> > + }
> >
> > - should XATTR_CREATE simply be 0?
> > XATTR_CREATE will fail if a similar xattr already exists I think.
>
> Ok. What does 0 do if one doesn't already exist? There's
> XATTR_REPLACE too which suggests that you either need one or the other.
0 (default) does the right thing. Create if it does not exist,
overwrite if they do.
REPLACE fails if it does not exist, CREATE fails if it does.
>
> No idea. Its tested on x86_64 with 64 bit userspace.
Okay.. never mind. this is not important :)
thanks
Murali
>
> -sam
> >
> > thanks,
> > Murali
> >
> >>
> >> -sam
> >>
> >>
> >>
> >>
> >>> thanks,
> >>> Murali
> >>>
> >>>> Maybe I'm missing something but I think deleting the file should be
> >>>> allowed, in fact it should be the only way to remove the immutable
> >>>> attribute.
> >>>>
> >>>> -sam
> >>>>
> >>>>> thanks,
> >>>>> Murali
> >>>>>>
> >>>>>> -sam
> >>>>>>
> >>>>>> On Aug 17, 2007, at 10:09 PM, Murali Vilayannur wrote:
> >>>>>>
> >>>>>>> Sam,
> >>>>>>> The problem is not in the system call (fsetxattr) but the
> >>>>>>> arguments
> >>>>>>> to it..
> >>>>>>> user.pvfs2.meta_hint is the key and val is actually a uint64
> >>>>>>> which is
> >>>>>>> a bitwise OR
> >>>>>>> of PVFS_IMMUTABLE_FL, other pvfs flags.
> >>>>>>> modify_val() in pvfs2-xattr.c will give an example of this
> >>>>>>> usage.
> >>>>>>> Sorry, it is a little convoluted ..:(
> >>>>>>> but I couldn't/didn't want to do more string parsing on server
> >>>>>>> side.
> >>>>>>> Feel free to change that if you think it is needlessly
> >>>>>>> convoluted.
> >>>>>>> thanks,
> >>>>>>> Murali
> >>>>>>>
> >>>>>>> PS: let me know how the caching patches work out :)
> >>>>>>> I havent had too much time to play with it since Feb though.
> >>>>>>> Hope it works :)
> >>>>>>>
> >>>>>>>
> >>>>>>> On 8/17/07, Sam Lang <[EMAIL PROTECTED]> wrote:
> >>>>>>>>
> >>>>>>>> Hi Murali,
> >>>>>>>>
> >>>>>>>> I wrote a little program to test the performance of the read-
> >>>>>>>> caching
> >>>>>>>> immutable file stuff. With the attached program, I get a
> >>>>>>>> EINVAL
> >>>>>>>> error on the read of the file after the immutable attribute has
> >>>>>>>> been
> >>>>>>>> set (using fsetxattr). Also, ls -la gives me really strange
> >>>>>>>> results
> >>>>>>>> for the files that I've set that immutable attribute on. In
> >>>>>>>> the
> >>>>>>>> below listing, tmpfile1 and tmpfile10 didn't have the immutable
> >>>>>>>> attribute set. It looks like the problem is with the fsetxattr
> >>>>>>>> system call. The setfattr util does the same thing. When I
> >>>>>>>> set
> >>>>>>>> the
> >>>>>>>> xattr with pvfs2-xattr though, I don't see the corruption in
> >>>>>>>> listing
> >>>>>>>> the file. I'll try to investigate what fsetxattr is doing,
> >>>>>>>> but are
> >>>>>>>> you aware of any problems with using the system call?
> >>>>>>>>
> >>>>>>>> -sam
> >>>>>>>>
> >>>>>>>> [EMAIL PROTECTED]:/tmp/pvfsmnt# ls -la
> >>>>>>>> total 10260
> >>>>>>>> drwxrwxrwt 1 slang mpi 4096 2007-08-17 16:35 .
> >>>>>>>> drwxrwxrwt 5 root root 4096 2007-08-17 15:47 ..
> >>>>>>>> drwxrwxrwx 1 slang mpi 4096 2007-08-17 15:47 lost+found
> >>>>>>>> -rw-r--r-- 1 root root 0 2007-08-17 16:24 tmpfile1
> >>>>>>>> -rw-r--r-- 1 root root 10485760 2007-08-17 16:34 tmpfile10
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile11
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile2
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile3
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile4
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile5
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile6
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile7
> >>>>>>>> ?--------- ? ? ? ? ? tmpfile9
> >>>>>>>> [EMAIL PROTECTED]:/tmp/pvfsmnt#
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> On Feb 20, 2007, at 1:06 AM, Murali Vilayannur wrote:
> >>>>>>>>
> >>>>>>>>> Hi all,
> >>>>>>>>> Finally, I got some time to whip up the read-caching
> >>>>>>>>> patches for
> >>>>>>>>> non-mutable files into a semblance of shape and stability.
> >>>>>>>>> With this patch, I am able to get I/Os to a file (marked
> >>>>>>>>> immutable)
> >>>>>>>>> serviced from the page-cache. One can tag a file as
> >>>>>>>>> immutable by
> >>>>>>>>> running,
> >>>>>>>>> ./src/apps/admin/pvfs2-xattr -s -k user.pvfs2.meta_hint -v
> >>>>>>>>> "+immutable" /path/to/pvfs2-file
> >>>>>>>>> To verify if a file is indeed tagged immutable,
> >>>>>>>>> ./src/apps/admin/pvfs2-xattr -t -k user.pvfs2.meta_hint /path/
> >>>>>>>>> to/
> >>>>>>>>> pvfs2-file
> >>>>>>>>> (or)
> >>>>>>>>> ./src/apps/admin/pvfs2-stat /path/to/pvfs2/file
> >>>>>>>>>
> >>>>>>>>> I have also added some preliminary statistics exported via
> >>>>>>>>> /proc/sys/pvfs2/stats/
> >>>>>>>>> that can be used as a placeholder for more interesting
> >>>>>>>>> statistics
> >>>>>>>>> later on.
> >>>>>>>>> Currently, it only shows # of reads, writes, hits in thepage-
> >>>>>>>>> cache
> >>>>>>>>> and misses.
> >>>>>>>>>
> >>>>>>>>> For some reason now, cache hits do not happen across a file
> >>>>>>>>> close.
> >>>>>>>>> Within a file open-close session, all reads get serviced from
> >>>>>>>>> the
> >>>>>>>>> cache though. Very weird.
> >>>>>>>>> My hunch is that file pages are somehow getting removed
> >>>>>>>>> from the
> >>>>>>>>> radix
> >>>>>>>>> tree of the address space due to some page-ref counting
> >>>>>>>>> issues. I
> >>>>>>>>> will
> >>>>>>>>> dig into this later this week.
> >>>>>>>>>
> >>>>>>>>> In any case, this code should not cause any regression of
> >>>>>>>>> older
> >>>>>>>>> code
> >>>>>>>>> paths (hopefully!) and should not impose any performance
> >>>>>>>>> penalties for
> >>>>>>>>> workloads making use of the page-cache because of the way we
> >>>>>>>>> aggregate
> >>>>>>>>> cache miss I/Os to the server.
> >>>>>>>>> It was really nice to be able to make use of the iox()
> >>>>>>>>> infrastructure
> >>>>>>>>> that was already in place to service non-contigous file and
> >>>>>>>>> memory
> >>>>>>>>> I/O.
> >>>>>>>>> More details of the implementation is described in the thread
> >>>>>>>>> below.
> >>>>>>>>> http://www.beowulf-underground.org/pipermail/pvfs2-developers/
> >>>>>>>>> 2006-
> >>>>>>>>> November/002847.html
> >>>>>>>>> Hopefully, I have addressed most of Pete's comments.
> >>>>>>>>> More comments and testing welcome!
> >>>>>>>>> thanks,
> >>>>>>>>> Murali
> >>>>>>>>> <read-cache-5.patch>
> >>>>>>>>> _______________________________________________
> >>>>>>>>> Pvfs2-developers mailing list
> >>>>>>>>> Pvfs2-developers@beowulf-underground.org
> >>>>>>>>> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-
> >>>>>>>>> developers
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>
> >>>>
> >>>>
> >>>
> >>
> >>
> >>
> >>
> >
>
>
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