On Tue, Jul 09, 2024 at 11:39:19PM +0200, Martin Wilck wrote: > Signed-off-by: Martin Wilck <[email protected]> > --- > libmultipath/devmapper.c | 53 ++++++---------------------------------- > 1 file changed, 8 insertions(+), 45 deletions(-) > > diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c > index 859a861..6276041 100644 > --- a/libmultipath/devmapper.c > +++ b/libmultipath/devmapper.c > @@ -965,52 +965,15 @@ static int dm_type_match(const char *name, char *type) > > int dm_is_mpath(const char *name) > { > - int r = DM_IS_MPATH_ERR; > - struct dm_task __attribute__((cleanup(cleanup_dm_task))) *dmt = NULL; > - struct dm_info info; > - uint64_t start, length; > - char *target_type = NULL; > - char *params; > - const char *uuid; > + char uuid[DM_UUID_LEN]; > + int rc = libmp_mapinfo(DM_MAP_BY_NAME, > + (mapid_t) { .str = name }, > + (mapinfo_t) { .uuid = uuid, .tgt_type = > TGT_MPATH }); > > - if (!(dmt = libmp_dm_task_create(DM_DEVICE_TABLE))) > - goto out; > - > - if (!dm_task_set_name(dmt, name)) > - goto out; > - > - if (!libmp_dm_task_run(dmt)) { > - dm_log_error(3, DM_DEVICE_TABLE, dmt); > - goto out; > - } > - > - if (!dm_task_get_info(dmt, &info)) > - goto out; > - > - r = DM_IS_MPATH_NO; > - > - if (!info.exists) > - goto out; > - > - uuid = dm_task_get_uuid(dmt); > - > - if (!uuid || strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN) != 0) > - goto out; > - > - /* Fetch 1st target */ > - if (dm_get_next_target(dmt, NULL, &start, &length, &target_type, > - ¶ms) != NULL) > - /* multiple targets */ > - goto out; > - > - if (!target_type || strcmp(target_type, TGT_MPATH) != 0) > - goto out; > - > - r = DM_IS_MPATH_YES; > -out: > - if (r < 0) > - condlog(3, "%s: dm command failed in %s: %s", name, __func__, > strerror(errno)); > - return r;
Since dm_get_events() and watch_dmevents() need to differentiate between DM_IS_MPATH_NO and DM_IS_MPATH_ERR, this function needs to return DM_IS_MPATH_ERR if libmp_mapinfo() returns DM_ERR. Looking over this function, I did notice one thing. It returns DM_IS_MPATH_ERR if dm_task_get_info() fails, while libmp_mapinfo__() returns DMP_NOT_FOUND if dm_task_get_info() fails. Looking at the current lvm code, I can't see a way for dm_task_get_info() to fail if we just called libmp_dm_task_run() and it succeeded. On the other hand dm_task_get_info() failing does seem to be an error, not a a sign that the device doesn't exist, so perhaps ibmp_mapinfo__() should treat it like one. Although most of our code doesn't, and like I said, I don't see how it could fail unless dm_task_run() already failed (or wasn't called). Any thoughts? -Ben > + if (rc != DMP_OK || strncmp(uuid, UUID_PREFIX, UUID_PREFIX_LEN)) > + return DM_IS_MPATH_NO; > + else > + return DM_IS_MPATH_YES; > } > > int dm_map_present_by_wwid(const char *wwid) > -- > 2.45.2
