replace non-POSIX error codes

Some DOMCTLs returned non-POSIX error codes, replace them with POSIX
compilant values instead. EBADRQC and EBADSLT are replaced by EDOM, while
EUSERS is replaced with EOVERFLOW.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>

Replace two EDOM uses.

Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>

xen/arch/x86/mm/paging.c

@@ -766,7 +766,7 @@ long paging_domctl_continuation(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
 
     if ( op.interface_version != XEN_DOMCTL_INTERFACE_VERSION ||
          op.cmd != XEN_DOMCTL_shadow_op )
-        return -EBADRQC;
+        return -EOPNOTSUPP;
 
     d = rcu_lock_domain_by_id(op.domain);
     if ( d == NULL )

xen/common/domain.c

@@ -900,7 +900,7 @@ int vcpu_pause_by_systemcontroller(struct vcpu *v)
         new = old + 1;
 
         if ( new > 255 )
-            return -EUSERS;
+            return -EOVERFLOW;
 
         prev = cmpxchg(&v->controller_pause_count, old, new);
     } while ( prev != old );
@@ -980,7 +980,7 @@ int __domain_pause_by_systemcontroller(struct domain *d,
          * toolstack overflowing d->pause_count with many repeated hypercalls.
          */
         if ( new > 255 )
-            return -EUSERS;
+            return -EOVERFLOW;
 
         prev = cmpxchg(&d->controller_pause_count, old, new);
     } while ( prev != old );

xen/common/hvm/save.c

@@ -114,7 +114,7 @@ int hvm_save_one(struct domain *d, uint16_t typecode, uint16_t instance,
         uint32_t off;
         const struct hvm_save_descriptor *desc;
 
-        rv = -EBADSLT;
+        rv = -ENOENT;
         for ( off = 0; off < (ctxt.cur - sizeof(*desc)); off += desc->length )
         {
             desc = (void *)(ctxt.data + off);