On Thu, 2020-07-02 at 19:06 -0500, Benjamin Marzinski wrote: > If a multipath device is removed, and check_path() checks one of its > paths before multipathd processes either the uevent or the dm event > from > removing it, multipathd will recreate the removed device. This > happens > because check_path() will continute to check the removed device's > former > paths until an event arrives removing the device. A missing multpath > device will cause the update_multipath_strings() call to fail, > setting > pp->dmstate to PSTATE_UNDEF. If the path is up, this dmstate will > cause > reinstate_path() to be called, which will also fail, because the > multipath device doesn't exist. This will trigger a reload, > restoring > the recently removed device. > > This patchset handles this is two ways. The first two patches > directly > fix these issues in check_path(), so that a missing multipath device > will no longer get recreated when checking one of its former paths. > > The other 5 patches add a "multipathd del maps" command, and make the > mutipath command delegate flush operations to multipathd so > multipathd's > state remains in sync with the kernel's, while doing removes. > > Changes from v1: > 0001: This is completely different. I've change how patch 0002 > detects > when a multipath device has disappeared. Instead of > do_get_info, > I need more return values on dm_get_map/status, and the > update_multipath_* functions. I have used symbolic return > values, which was the objection to the previous patch. I tried > to picked generic enough names that they could be used for > other > devmapper.c functions as well. > > 0002: At Martin's suggestion, multipath now differentiates between dm > failures and a missing multipath device in > update_multipath_strings(). So there is no need to recheck if > the device is missing. > > 0006: Added some man page info that was previously in patch 0007 > > 0007: Removed mentions of the -D option in the man page and usage > output. > > Changes from v2 (all are Martin's suggestions): > 0001: Using dm_task_get_errno() and changed the names and values of > the symbolic returns. > > 0002: Changed symbolic return names, and improved some logging. > > Benjamin Marzinski (7): > libmultipath: make dm_get_map/status return codes symbolic > multipathd: fix check_path errors with removed map > libmultipath: make dm_flush_maps only return 0 on success > multipathd: add "del maps" multipathd command > multipath: make flushing maps work like other commands > multipath: delegate flushing maps to multipathd > multipath: add option to skip multipathd delegation > > libmultipath/config.h | 4 ++- > libmultipath/configure.h | 3 -- > libmultipath/devmapper.c | 63 +++++++++++++++++++++++++----------- > -- > libmultipath/devmapper.h | 8 ++++- > libmultipath/structs_vec.c | 45 +++++++++++++++------------ > multipath/main.c | 44 ++++++++++++++++++-------- > multipath/multipath.8 | 4 +-- > multipathd/cli.c | 1 + > multipathd/cli_handlers.c | 19 ++++++++++++ > multipathd/cli_handlers.h | 1 + > multipathd/main.c | 57 ++++++++++++++++------------------ > multipathd/main.h | 1 + > 12 files changed, 160 insertions(+), 90 deletions(-) > For the set: Reviewed-by: Martin Wilck <mwilck@xxxxxxxx> -- Dr. Martin Wilck <mwilck@xxxxxxxx>, Tel. +49 (0)911 74053 2107 SUSE Software Solutions Germany GmbH HRB 36809, AG Nürnberg GF: Felix Imendörffer -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
