On Thu, 2023-11-02 at 18:15 -0400, Benjamin Marzinski wrote:
> When resizing a multipath device, make sure that all the paths have
> been updated to the new size first.
>
> Signed-off-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx>
> ---
> multipathd/cli_handlers.c | 30 +++++++++++++++++-------------
> 1 file changed, 17 insertions(+), 13 deletions(-)
>
> diff --git a/multipathd/cli_handlers.c b/multipathd/cli_handlers.c
> index c9addfbb..ffea193d 100644
> --- a/multipathd/cli_handlers.c
> +++ b/multipathd/cli_handlers.c
> @@ -845,9 +845,11 @@ cli_resize(void *v, struct strbuf *reply, void
> *data)
> char * mapname = get_keyparam(v, KEY_MAP);
> struct multipath *mpp;
> int minor;
> - unsigned long long size;
> + unsigned long long size = 0;
> struct pathgroup *pgp;
> struct path *pp;
> + unsigned int i, j;
> + bool mismatch = false;
>
> mapname = convert_dev(mapname, 0);
> condlog(2, "%s: resize map (operator)", mapname);
> @@ -867,21 +869,23 @@ cli_resize(void *v, struct strbuf *reply, void
> *data)
> return 1;
> }
>
> - pgp = VECTOR_SLOT(mpp->pg, 0);
> -
> - if (!pgp){
> - condlog(0, "%s: couldn't get path group. cannot
> resize",
> - mapname);
> - return 1;
> + vector_foreach_slot(mpp->pg, pgp, i) {
> + vector_foreach_slot (pgp->paths, pp, j) {
> + if (sysfs_get_size(pp, &pp->size) != 0)
> + continue;
> + if (!size)
> + size = pp->size;
In the previous patch, you assume that if sysfs_get_size() fails, the
size is unchanged. The "continue" doesn't make much sense to me: you
should make the same assumption here, i.e. set size = pp->size even in
the failure case. Otherwise you might miss a size mismatch.
Altenatively, you could error out immediately if sysfs_get_size() fails
for any path.
Martin
> + else if (pp->size != size)
> + mismatch = true;
> + }
> }
> - pp = VECTOR_SLOT(pgp->paths, 0);
> -
> - if (!pp){
> - condlog(0, "%s: couldn't get path. cannot resize",
> mapname);
> + if (!size) {
> + condlog(0, "%s: couldn't get size from sysfs. cannot
> resize",
> + mapname);
> return 1;
> }
> - if (!pp->udev || sysfs_get_size(pp, &size)) {
> - condlog(0, "%s: couldn't get size for sysfs. cannot
> resize",
> + if (mismatch) {
> + condlog(0, "%s: path size not consistent. cannot
> resize",
> mapname);
> return 1;
> }
