domain: add __kdbus_domain_user_account() to account domain users

Add __kdbus_domain_user_account() to account and link users into a
domain.

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>

diff --git a/domain.c b/domain.c
index af9d9863991b5f03ca3ab376b2c87173872aff42..11d7439b724d030b2352b85a7b1365e12dc7bf2f 100644 (file)
--- a/domain.c
+++ b/domain.c
@@ -451,6 +451,76 @@ static int kdbus_domain_user_assign_id(struct kdbus_domain *domain,
        return 0;
 }
 
+/**
+ * __kdbus_domain_user_account() - account a kdbus_domain_user object
+ *                                into the specified domain
+ * @domain:            The domain of the user
+ * @uid:               The uid of the user; INVALID_UID for an
+ *                     anonymous user like a custom endpoint
+ * @user               Pointer to a reference where the accounted
+ *                     domain user will be stored.
+ *
+ * Return: 0 on success, negative errno on failure.
+ *
+ * On success: if there is a uid matching, then use the already
+ * accounted kdbus_domain_user, increment its reference counter and
+ * return it in the 'user' argument. Otherwise, allocate a new one,
+ * link it into the domain, then return it.
+ *
+ * On failure: the 'user' argument is not updated.
+ *
+ * Caller must have the domain lock held and must ensure that the
+ * domain was not disconnected.
+ */
+int __kdbus_domain_user_account(struct kdbus_domain *domain,
+                               kuid_t uid,
+                               struct kdbus_domain_user **user)
+{
+       int ret;
+       struct kdbus_domain_user *tmp_user;
+       struct kdbus_domain_user *u = NULL;
+
+       /* find uid and reference it */
+       if (uid_valid(uid)) {
+               hash_for_each_possible(domain->user_hash, tmp_user,
+                                      hentry, __kuid_val(uid)) {
+                       if (!uid_eq(tmp_user->uid, uid))
+                               continue;
+
+                       u = kdbus_domain_user_ref(tmp_user);
+                       goto out;
+               }
+       }
+
+       ret = -ENOMEM;
+       u = kzalloc(sizeof(*u), GFP_KERNEL);
+       if (!u)
+               return ret;
+
+       kref_init(&u->kref);
+       u->domain = kdbus_domain_ref(domain);
+       u->uid = uid;
+       atomic_set(&u->buses, 0);
+       atomic_set(&u->connections, 0);
+
+       /* Assign user ID and link into domain */
+       ret = kdbus_domain_user_assign_id(domain, u);
+       if (ret < 0)
+               goto exit_free;
+
+       /* UID hash map */
+       hash_add(domain->user_hash, &u->hentry, __kuid_val(u->uid));
+
+out:
+       *user = u;
+       return 0;
+
+exit_free:
+       kdbus_domain_unref(u->domain);
+       kfree(u);
+       return ret;
+}
+
 /**
  * kdbus_domain_user_find_or_new() - get a kdbus_domain_user object in a domain
  * @domain:            The domain

diff --git a/domain.h b/domain.h
index 9c477dbfe82507d29ea8ad99913a00e6137349be..fd2940ba860f8416c52cf9cd24d7e2b7ecfb91de 100644 (file)
--- a/domain.h
+++ b/domain.h
@@ -99,6 +99,10 @@ int kdbus_domain_new(struct kdbus_domain *parent, const char *name,
 int kdbus_domain_make_user(struct kdbus_cmd_make *cmd, char **name);
 struct kdbus_domain *kdbus_domain_find_by_major(unsigned int major);
 
+int __kdbus_domain_user_account(struct kdbus_domain *domain,
+                               kuid_t uid,
+                               struct kdbus_domain_user **user);
+
 struct kdbus_domain_user
 *kdbus_domain_user_find_or_new(struct kdbus_domain *domain, kuid_t uid);
 struct kdbus_domain_user *kdbus_domain_user_ref(struct kdbus_domain_user *u);