Rearchitect quota checking to partially fix bug 938317.

This is a rearchitecting/rewriting of quota handling to correct the
quota atomicity issues highlighted by bug 938317.  Partially implements
blueprint quota-refactor as well.

This change is fairly substantial.  To make it easier to review, it has been
broken up into 3 parts.  This is the first part.

Change-Id: I805f5750c08de17487e59fe33fad0bed203188a6

1 files changed, 25 insertions, 0 deletions

diff --git a/nova/exception.py b/nova/exception.py
index af4850367..bcca2a6dc 100644
--- a/nova/exception.py
+++ b/nova/exception.py
@@ -689,10 +689,23 @@ class AccessKeyNotFound(NotFound):
     message = _("Access Key %(access_key)s could not be found.")
 
 
+class InvalidReservationExpiration(Invalid):
+    message = _("Invalid reservation expiration %(expire)s.")
+
+
+class InvalidQuotaValue(Invalid):
+    message = _("Change would make usage less than 0 for the following "
+                "resources: %(unders)s")
+
+
 class QuotaNotFound(NotFound):
     message = _("Quota could not be found")
 
 
+class QuotaResourceUnknown(QuotaNotFound):
+    message = _("Unknown quota resources %(unknown)s.")
+
+
 class ProjectQuotaNotFound(QuotaNotFound):
     message = _("Quota for project %(project_id)s could not be found.")
 
@@ -701,6 +714,18 @@ class QuotaClassNotFound(QuotaNotFound):
     message = _("Quota class %(class_name)s could not be found.")
 
 
+class QuotaUsageNotFound(QuotaNotFound):
+    message = _("Quota usage for project %(project_id)s could not be found.")
+
+
+class ReservationNotFound(QuotaNotFound):
+    message = _("Quota reservation %(uuid)s could not be found.")
+
+
+class OverQuota(NovaException):
+    message = _("Quota exceeded for resources: %(overs)s")
+
+
 class SecurityGroupNotFound(NotFound):
     message = _("Security group %(security_group_id)s not found.")