On Thu, Mar 31, 2022 at 2:25 PM Christian Brauner <brauner@xxxxxxxxxx> wrote: > > In addition to the generic and filesystem-specific idmapped mount > testsuites that already exist upstream today add simple infrastructure > so any test can be run on idmapped mounts simply by setting > IDMAPPED_MOUNTS=true in the config file or section. The main user for > now will be overlay to verify it works correctly on idmapped mounts. > > Note that the infrastructure is completely generic so every filesystem that > supports idmapped mounts can simply run all of their tests idmapped. But > note that not all ways to create a mount have been converted yet. That > includes e.g. _dmthin_mount and direct calls to _mount in various tests. > > In addition, there will be corner-cases. For example, xfs doesn't allow > bulkstat on idmapped mounts because it is a filesystem wide operation, > i.e. you can retrieve information for any inode in the filesystem so the > operation cannot be scoped reasonably under a single mount. So xfstests > testing bulkstat will fail as it's blocked. Similar for some btrfs > ioctl()s. > > While we could of course restrict this testmode to -overlay for which we > know things work correctly we should not do this. It would mean that > people won't start using it and so we won't see issues unless someone > sits down and goes through more than 1000 tests and figures out for each > individual one whether it needs to be skipped or not. > > So instead allow this mode but for all filesystems so people can start > running and reporting failures and we can fix them up or block them as > we detect them. > > Cc: Amir Goldstein <amir73il@xxxxxxxxx> > Cc: Eryu Guan <guaneryu@xxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: <fstests@xxxxxxxxxxxxxxx> > Signed-off-by: Christian Brauner (Microsoft) <brauner@xxxxxxxxxx> > --- > /* v2 */ > unchanged > > /* v3 */ > - Amir Goldstein <amir73il@xxxxxxxxx>: > - Add more detailed explanation about the current state and > expectations of the newly added IDMAPPED_MOUNTS support. Please document the new envvar in README with a *short* disclaimer about expectations with and without -overlay and please add an [idmapped] section to the multi section config example in README.overlay. Sorry if I wasn't clear about what better documentation of expectations the text in the commit message is important but is no replacement for documentation. Thanks, Amir.
