[PATCH 4/4] nvme: check that EUI/GUID/UUID are globally unique

Christoph Hellwig
2022-02-24T19:29:38Z

Add a check to verify that the unique identifiers are unique globally
in addition to the existing check that verifies that they are unique
inside a single subsystem.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/nvme/host/core.c | 38 ++++++++++++++++++++++++++++++++++++--
1 file changed, 36 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index cece987ba1691..f8084ded69e50 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3810,12 +3810,45 @@ static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
return ERR_PTR(ret);
}

+static int nvme_global_check_duplicate_ids(struct nvme_subsystem *this,
+ struct nvme_ns_ids *ids)
+{
+ struct nvme_subsystem *s;
+ int ret = 0;
+
+ /*
+ * Note that this check is racy as we try to avoid holding the global
+ * lock over the whole ns_head creation. But it is only intended as
+ * a sanity check anyway.
+ */
+ mutex_lock(&nvme_subsystems_lock);
+ list_for_each_entry(s, &nvme_subsystems, entry) {
+ if (s == this)
+ continue;
+ mutex_lock(&s->lock);
+ ret = nvme_subsys_check_duplicate_ids(s, ids);
+ mutex_unlock(&s->lock);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&nvme_subsystems_lock);
+
+ return ret;
+}
+
static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
struct nvme_ns_ids *ids, bool is_shared)
{
struct nvme_ctrl *ctrl = ns->ctrl;
struct nvme_ns_head *head = NULL;
- int ret = 0;
+ int ret;
+
+ ret = nvme_global_check_duplicate_ids(ctrl->subsys, ids);
+ if (ret) {
+ dev_err(ctrl->device,
+ "globally duplicate IDs for nsid %d\n", nsid);
+ return ret;
+ }

mutex_lock(&ctrl->subsys->lock);
head = nvme_find_ns_head(ctrl->subsys, nsid);
@@ -3823,7 +3856,8 @@ static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
ret = nvme_subsys_check_duplicate_ids(ctrl->subsys, ids);
if (ret) {
dev_err(ctrl->device,
- "duplicate IDs for nsid %d\n", nsid);
+ "duplicate IDs in subsystem for nsid %d\n",
+ nsid);
goto out_unlock;
}
head = nvme_alloc_ns_head(ctrl, nsid, ids);
--
2.30.2