Hi!
> On Thu, 2005-01-27 at 14:26, Jan Kara wrote:
> > Hello,
> >
> > > On Thu, 2005-01-27 at 10:24, Sergey S. Kostyliov wrote:
> > > > Hello all,
> > > >
> > > > Here is a BUG() I've just hited on quota enabled reiserfs disk.
> > > >
> > > > [EMAIL PROTECTED] rathamahata $ mount | grep /dev/sdb2
> > > > /dev/sdb2 on /var/www type reiserfs
> > > > (rw,noatime,nodiratime,data=writeback,grpquota,usrquota)
> > > > [EMAIL PROTECTED] rathamahata $
> > > >
> > > > REISERFS: panic (device sdb2): journal_begin called without kernel lock
> > > > held
> > >
> > > Would you check whether this patch helps, please?
> > BTW: What are the exact rules where lock_kernel() should be held for
> > reiserfs? Is there a doc somewhere?
> I do not think so.
> Earlier reiserfs used to lock_kernel on entering and unlock on exit. The
> reason is that reiserfs has no fine grain locking protecting access to
> its data structures.
> Since that time there could be introduced some minor improvements,
> though.
So in that case reiserfs_quota_read() also needs a BKL
because it can be called from the quota code without any lock
guarantees (e.g. quota_on() and quotactl() can call reading routine
without BKL).
Attached patch adds this BKL locking and adds also missing
lock_buffer() I found.
If you agree with the patch then you can forward it to Andrew/Linus.
Honza
--
Jan Kara <[EMAIL PROTECTED]>
SuSE CR Labs
Add missing locking to reiserfs_quota_read() and reiserfs_quota_write().
Signed-off-by: Jan Kara <[EMAIL PROTECTED]>
--- linux/fs/reiserfs/super.c 2005-01-27 12:56:27.000000000 +0100
+++ linux/fs/reiserfs/super.c 2005-01-27 17:41:20.000000000 +0100
@@ -1993,7 +1993,9 @@ static ssize_t reiserfs_quota_read(struc
tocopy = sb->s_blocksize - offset < toread ? sb->s_blocksize - offset :
toread;
tmp_bh.b_state = 0;
/* Quota files are without tails so we can safely use this function */
+ reiserfs_write_lock(sb);
err = reiserfs_get_block(inode, blk, &tmp_bh, 0);
+ reiserfs_write_unlock(sb);
if (err)
return err;
if (!buffer_mapped(&tmp_bh)) /* A hole? */
@@ -2041,8 +2043,11 @@ static ssize_t reiserfs_quota_write(stru
err = -EIO;
goto out;
}
+ lock_buffer(bh);
memcpy(bh->b_data+offset, data, tocopy);
+ flush_dcache_page(bh->b_page);
set_buffer_uptodate(bh);
+ unlock_buffer(bh);
reiserfs_prepare_for_journal(sb, bh, 1);
journal_mark_dirty(current->journal_info, sb, bh);
if (!journal_quota)
