domctl: improve device assignment structure layout and use

Avoid needless gaps. Make flags field mandatory for all three
operations (and rename it to fit the intended future purpose of
possibly holding more than just one flag).

Also correct a typo in a related domctl.h comment.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>

diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
index a447405903ff5c2323eb26818fc081af7a9f62fd..b1a286ecf4ce0813ba58e9e652d87783826b5ef5 100644 (file)
--- a/tools/libxc/xc_domain.c
+++ b/tools/libxc/xc_domain.c
@@ -1488,7 +1488,7 @@ int xc_assign_device(
     xc_interface *xch,
     uint32_t domid,
     uint32_t machine_sbdf,
-    uint32_t flag)
+    uint32_t flags)
 {
     DECLARE_DOMCTL;
 
@@ -1496,7 +1496,7 @@ int xc_assign_device(
     domctl.domain = domid;
     domctl.u.assign_device.dev = XEN_DOMCTL_DEV_PCI;
     domctl.u.assign_device.u.pci.machine_sbdf = machine_sbdf;
-    domctl.u.assign_device.flag = flag;
+    domctl.u.assign_device.flags = flags;
 
     return do_domctl(xch, &domctl);
 }
@@ -1547,6 +1547,7 @@ int xc_test_assign_device(
     domctl.domain = domid;
     domctl.u.assign_device.dev = XEN_DOMCTL_DEV_PCI;
     domctl.u.assign_device.u.pci.machine_sbdf = machine_sbdf;
+    domctl.u.assign_device.flags = 0;
 
     return do_domctl(xch, &domctl);
 }
@@ -1562,6 +1563,7 @@ int xc_deassign_device(
     domctl.domain = domid;
     domctl.u.assign_device.dev = XEN_DOMCTL_DEV_PCI;
     domctl.u.assign_device.u.pci.machine_sbdf = machine_sbdf;
+    domctl.u.assign_device.flags = 0;
 
     return do_domctl(xch, &domctl);
 }
@@ -1588,7 +1590,7 @@ int xc_assign_dt_device(
      * DT doesn't own any RDM so actually DT has nothing to do
      * for any flag and here just fix that as 0.
      */
-    domctl.u.assign_device.flag = 0;
+    domctl.u.assign_device.flags = 0;
     set_xen_guest_handle(domctl.u.assign_device.u.dt.path, path);
 
     rc = do_domctl(xch, &domctl);
@@ -1617,6 +1619,7 @@ int xc_test_assign_dt_device(
     domctl.u.assign_device.dev = XEN_DOMCTL_DEV_DT;
     domctl.u.assign_device.u.dt.size = size;
     set_xen_guest_handle(domctl.u.assign_device.u.dt.path, path);
+    domctl.u.assign_device.flags = 0;
 
     rc = do_domctl(xch, &domctl);
 
@@ -1644,6 +1647,7 @@ int xc_deassign_dt_device(
     domctl.u.assign_device.dev = XEN_DOMCTL_DEV_DT;
     domctl.u.assign_device.u.dt.size = size;
     set_xen_guest_handle(domctl.u.assign_device.u.dt.path, path);
+    domctl.u.assign_device.flags = 0;
 
     rc = do_domctl(xch, &domctl);
 

diff --git a/xen/drivers/passthrough/device_tree.c b/xen/drivers/passthrough/device_tree.c
index 79bf8bf5edb813c89902f5d8e5b30fd48681ba2b..99ed49ecd82abe7347db83250397ff761ca341ab 100644 (file)
--- a/xen/drivers/passthrough/device_tree.c
+++ b/xen/drivers/passthrough/device_tree.c
@@ -147,11 +147,9 @@ int iommu_do_dt_domctl(struct xen_domctl *domctl, struct domain *d,
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_DT )
             break;
 
-        if ( unlikely(d->is_dying) )
-        {
-            ret = -EINVAL;
+        ret = -EINVAL;
+        if ( d->is_dying || domctl->u.assign_device.flags )
             break;
-        }
 
         ret = dt_find_node_by_gpath(domctl->u.assign_device.u.dt.path,
                                     domctl->u.assign_device.u.dt.size,
@@ -176,6 +174,10 @@ int iommu_do_dt_domctl(struct xen_domctl *domctl, struct domain *d,
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_DT )
             break;
 
+        ret = -EINVAL;
+        if ( domctl->u.assign_device.flags )
+            break;
+
         ret = dt_find_node_by_gpath(domctl->u.assign_device.u.dt.path,
                                     domctl->u.assign_device.u.dt.size,
                                     &dev);
@@ -197,6 +199,10 @@ int iommu_do_dt_domctl(struct xen_domctl *domctl, struct domain *d,
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_DT )
             break;
 
+        ret = -EINVAL;
+        if ( domctl->u.assign_device.flags )
+            break;
+
         ret = dt_find_node_by_gpath(domctl->u.assign_device.u.dt.path,
                                     domctl->u.assign_device.u.dt.size,
                                     &dev);

diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index c8e2d2d9a9c4bda48d68d15869853c4733788b4e..6e7126b2e86de1ea467f5ff12e4fccfb01001b40 100644 (file)
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -1540,12 +1540,13 @@ int iommu_do_pci_domctl(
 {
     u16 seg;
     u8 bus, devfn;
-    u32 flag;
     int ret = 0;
     uint32_t machine_sbdf;
 
     switch ( domctl->cmd )
     {
+        unsigned int flags;
+
     case XEN_DOMCTL_get_device_group:
     {
         u32 max_sdevs;
@@ -1583,6 +1584,10 @@ int iommu_do_pci_domctl(
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_PCI )
             break;
 
+        ret = -EINVAL;
+        if ( domctl->u.assign_device.flags )
+            break;
+
         machine_sbdf = domctl->u.assign_device.u.pci.machine_sbdf;
 
         ret = xsm_test_assign_device(XSM_HOOK, machine_sbdf);
@@ -1614,11 +1619,10 @@ int iommu_do_pci_domctl(
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_PCI )
             break;
 
-        if ( unlikely(d->is_dying) )
-        {
-            ret = -EINVAL;
+        ret = -EINVAL;
+        flags = domctl->u.assign_device.flags;
+        if ( d->is_dying || (flags & ~XEN_DOMCTL_DEV_RDM_RELAXED) )
             break;
-        }
 
         machine_sbdf = domctl->u.assign_device.u.pci.machine_sbdf;
 
@@ -1629,15 +1633,9 @@ int iommu_do_pci_domctl(
         seg = machine_sbdf >> 16;
         bus = PCI_BUS(machine_sbdf);
         devfn = PCI_DEVFN2(machine_sbdf);
-        flag = domctl->u.assign_device.flag;
-        if ( flag & ~XEN_DOMCTL_DEV_RDM_RELAXED )
-        {
-            ret = -EINVAL;
-            break;
-        }
 
         ret = device_assigned(seg, bus, devfn) ?:
-              assign_device(d, seg, bus, devfn, flag);
+              assign_device(d, seg, bus, devfn, flags);
         if ( ret == -ERESTART )
             ret = hypercall_create_continuation(__HYPERVISOR_domctl,
                                                 "h", u_domctl);
@@ -1661,6 +1659,10 @@ int iommu_do_pci_domctl(
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_PCI )
             break;
 
+        ret = -EINVAL;
+        if ( domctl->u.assign_device.flags )
+            break;
+
         machine_sbdf = domctl->u.assign_device.u.pci.machine_sbdf;
 
         ret = xsm_deassign_device(XSM_HOOK, d, machine_sbdf);

diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index 515c603dbce7ccfd0b7610dc4889545ab83d8f06..3f3b3ebaee1962248e2a0ebb4e165e509a84d4cc 100644 (file)
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -511,14 +511,17 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_sendtrigger_t);
  * XEN_DOMCTL_deassign_device: The behavior of this DOMCTL differs
  * between the different type of device:
  *  - PCI device (XEN_DOMCTL_DEV_PCI) will be reassigned to DOM0
- *  - DT device (XEN_DOMCTL_DT_PCI) will left unassigned. DOM0
+ *  - DT device (XEN_DOMCTL_DEV_DT) will left unassigned. DOM0
  *  will have to call XEN_DOMCTL_assign_device in order to use the
  *  device.
  */
 #define XEN_DOMCTL_DEV_PCI      0
 #define XEN_DOMCTL_DEV_DT       1
 struct xen_domctl_assign_device {
+    /* IN */
     uint32_t dev;   /* XEN_DOMCTL_DEV_* */
+    uint32_t flags;
+#define XEN_DOMCTL_DEV_RDM_RELAXED      1 /* assign only */
     union {
         struct {
             uint32_t machine_sbdf;   /* machine PCI ID of assigned device */
@@ -528,9 +531,6 @@ struct xen_domctl_assign_device {
             XEN_GUEST_HANDLE_64(char) path; /* path to the device tree node */
         } dt;
     } u;
-    /* IN */
-#define XEN_DOMCTL_DEV_RDM_RELAXED      1
-    uint32_t  flag;   /* flag of assigned device */
 };
 typedef struct xen_domctl_assign_device xen_domctl_assign_device_t;
 DEFINE_XEN_GUEST_HANDLE(xen_domctl_assign_device_t);