On 11/15/12 7:14 PM, Dave Chinner wrote: > From: Dave Chinner <dchinner@xxxxxxxxxx> > > When we initial xfs_quota, we place lots of information into the > fs_table. This includes all the devices/mount points the user has > specified as a global command line parameter to report on, as well > as all the paths under project quota control. > > There is a "current path" pointer (fs_path) maintained by the code > that points somewhere into the fs_table. After the table is > initialised, fs_path always points to the last entry in the table, > and hence has to be re-initialised to point at the desired entry > before it can be used properly. > > In the case of xfs_quota, if the command passed on the command line > is a non-global command, the command is called multiple times, each > time after the libxcmd args_command() callback is run. That starts > with an index of 0, and until the callback returns zero it will keep > passing whatever the last returned value was into the callback. > > xfs_quota supplies such a callback, and it's purpose is to iterate > over the fs_table setting fs_path to the next mount point in the > table. IOWs, non-global quota functions get called once for each > mount point specified on the command line. However, it also means > that for global functions, the fs_path pointer is not > re-initialised and hence if there are project quotas configured the > fs_path pointer does not point to a mount point andhence commands > may malfunction.. > > The problem that demonstrated this is the report function. It does > it's own fs_table iteration if the command requires it, and so only > should be called once to avoid outputting the same information > multiple times. That's what the previous patch fixed by making the > command global, but this now has the effect of making commands that > need to operate on the device specified on the global command rely > on the fs_path variable pointing at that device. > > Further, commands executed by the interactive method are always > treated as global commands, so the report command never worked as a > global command in the presence of a configured project quota setup. > > Fix the problem by initialising the fs_path pointer correctly. tl;dr ;) I'm all for detailed commit messages but you lost me there. If I were searching for this fix I'd have no idea what behavior this commit actually . . . fixes. :) Can you say: a) what the "previous patch" commit was, and b) what commandline triggers this problem, and what the result is? Sorry if I'm dense, -Eric > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> > --- > quota/init.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/quota/init.c b/quota/init.c > index 3293b90..0b481f7 100644 > --- a/quota/init.c > +++ b/quota/init.c > @@ -140,6 +140,15 @@ init( > > init_commands(); > add_args_command(init_args_command); > + > + /* > + * Ensure that global commands don't end up with an invalid path pointer > + * by setting the default device at the first specified on the CLI > + */ > + if (argc != optind) > + fs_path = fs_table_lookup(argv[optind], FS_MOUNT_POINT); > + else > + fs_path = &fs_table[0]; > } > > int > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
