[RFC XEN PATCH v4 4/5] domctl: Use gsi to grant/revoke irq permission

[Jiqian Chen]

Some type of domain don't have PIRQ, like PVH, current
implementation is not suitable for those domain.

When passthrough a device to guest on PVH dom0, this
pci_add_dm_done->XEN_DOMCTL_irq_permission will failed
at domain_pirq_to_irq.

So, change it to use gsi to grant/revoke irq permission.
And change the caller of XEN_DOMCTL_irq_permission to
pass gsi to it instead of pirq.

Co-developed-by: Huang Rui <ray.hu...@amd.com>
Signed-off-by: Jiqian Chen <jiqian.c...@amd.com>
---
 tools/libs/light/libxl_pci.c |  6 ++++--
 tools/libs/light/libxl_x86.c |  5 ++++-
 xen/common/domctl.c          | 12 ++++++++++--
 3 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/tools/libs/light/libxl_pci.c b/tools/libs/light/libxl_pci.c
index 96cb4da0794e..e1341d1e9850 100644
--- a/tools/libs/light/libxl_pci.c
+++ b/tools/libs/light/libxl_pci.c
@@ -1418,6 +1418,7 @@ static void pci_add_dm_done(libxl__egc *egc,
     unsigned long long start, end, flags, size;
     int irq, i;
     int r;
+    int gsi;
     uint32_t flag = XEN_DOMCTL_DEV_RDM_RELAXED;
     uint32_t domainid = domid;
     bool isstubdom = libxl_is_stubdom(ctx, domid, &domainid);
@@ -1486,6 +1487,7 @@ static void pci_add_dm_done(libxl__egc *egc,
         goto out_no_irq;
     }
     if ((fscanf(f, "%u", &irq) == 1) && irq) {
+        gsi = irq;
         r = xc_physdev_map_pirq(ctx->xch, domid, irq, &irq);
         if (r < 0) {
             LOGED(ERROR, domainid, "xc_physdev_map_pirq irq=%d (error=%d)",
@@ -1494,10 +1496,10 @@ static void pci_add_dm_done(libxl__egc *egc,
             rc = ERROR_FAIL;
             goto out;
         }
-        r = xc_domain_irq_permission(ctx->xch, domid, irq, 1);
+        r = xc_domain_irq_permission(ctx->xch, domid, gsi, 1);
         if (r < 0) {
             LOGED(ERROR, domainid,
-                  "xc_domain_irq_permission irq=%d (error=%d)", irq, r);
+                  "xc_domain_irq_permission irq=%d (error=%d)", gsi, r);
             fclose(f);
             rc = ERROR_FAIL;
             goto out;
diff --git a/tools/libs/light/libxl_x86.c b/tools/libs/light/libxl_x86.c
index d16573e72cd4..88ad50cf6360 100644
--- a/tools/libs/light/libxl_x86.c
+++ b/tools/libs/light/libxl_x86.c
@@ -654,12 +654,15 @@ out:
 int libxl__arch_domain_map_irq(libxl__gc *gc, uint32_t domid, int irq)
 {
     int ret;
+    int gsi;
+
+    gsi = irq;
 
     ret = xc_physdev_map_pirq(CTX->xch, domid, irq, &irq);
     if (ret)
         return ret;
 
-    ret = xc_domain_irq_permission(CTX->xch, domid, irq, 1);
+    ret = xc_domain_irq_permission(CTX->xch, domid, gsi, 1);
 
     return ret;
 }
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index f5a71ee5f78d..eeb975bd0194 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -653,12 +653,20 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
u_domctl)
         unsigned int pirq = op->u.irq_permission.pirq, irq;
         int allow = op->u.irq_permission.allow_access;
 
-        if ( pirq >= current->domain->nr_pirqs )
+        if ( pirq >= nr_irqs_gsi )
         {
             ret = -EINVAL;
             break;
         }
-        irq = pirq_access_permitted(current->domain, pirq);
+
+        if ( irq_access_permitted(current->domain, pirq) )
+            irq = pirq;
+        else
+        {
+            ret = -EPERM;
+            break;
+        }
+
         if ( !irq || xsm_irq_permission(XSM_HOOK, d, irq, allow) )
             ret = -EPERM;
         else if ( allow )
-- 
2.34.1