Message ID | 20210827191809.3118103-4-mcgrof@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | block: first batch of add_disk() error handling conversions | expand |
On Fri, Aug 27, 2021 at 12:18:02PM -0700, Luis Chamberlain wrote: > @@ -479,13 +479,17 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) > static void nvme_mpath_set_live(struct nvme_ns *ns) > { > struct nvme_ns_head *head = ns->head; > + int rc; > > if (!head->disk) > return; > > - if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { > - device_add_disk(&head->subsys->dev, head->disk, > - nvme_ns_id_attr_groups); > + if (!test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { This should still be test_and_set_bit() because it is protecting against two nvme paths simultaneously calling device_add_disk() on the same namespace head. > + rc = device_add_disk(&head->subsys->dev, head->disk, > + nvme_ns_id_attr_groups); > + if (rc) > + return; > + set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags); > nvme_add_ns_head_cdev(head); > }
On Fri, Aug 27, 2021 at 01:29:32PM -0700, Keith Busch wrote: > On Fri, Aug 27, 2021 at 12:18:02PM -0700, Luis Chamberlain wrote: > > @@ -479,13 +479,17 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) > > static void nvme_mpath_set_live(struct nvme_ns *ns) > > { > > struct nvme_ns_head *head = ns->head; > > + int rc; > > > > if (!head->disk) > > return; > > > > - if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { > > - device_add_disk(&head->subsys->dev, head->disk, > > - nvme_ns_id_attr_groups); > > + if (!test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { > > This should still be test_and_set_bit() because it is protecting against > two nvme paths simultaneously calling device_add_disk() on the same > namespace head. Interesting, I'll add a comment as well, as this was not clear with the drive by effort. Luis
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index 37ce3e8b1db2..f95643629fdb 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -479,13 +479,17 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head) static void nvme_mpath_set_live(struct nvme_ns *ns) { struct nvme_ns_head *head = ns->head; + int rc; if (!head->disk) return; - if (!test_and_set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { - device_add_disk(&head->subsys->dev, head->disk, - nvme_ns_id_attr_groups); + if (!test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) { + rc = device_add_disk(&head->subsys->dev, head->disk, + nvme_ns_id_attr_groups); + if (rc) + return; + set_bit(NVME_NSHEAD_DISK_LIVE, &head->flags); nvme_add_ns_head_cdev(head); }
We never checked for errors on add_disk() as this function returned void. Now that this is fixed, use the shiny new error handling. Since we now can tell for sure when a disk was added, move setting the bit NVME_NSHEAD_DISK_LIVE only when we did add the disk successfully. Nothing to do here as the cleanup is done elsewhere. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> --- drivers/nvme/host/multipath.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)