[PATCH v6 05/15] xen: extend domctl interface for cache coloring

[Carlo Nonato <carlo.nonato@xxxxxxxxxxxxxxx>]

Update the domctl interface to allow the user to set coloring configurations
from the toolstack.

Implement also the functionality for arm64.

Based on original work from: Luca Miccio <lucmiccio@xxxxxxxxx>

Signed-off-by: Carlo Nonato <carlo.nonato@xxxxxxxxxxxxxxx>
Signed-off-by: Marco Solieri <marco.solieri@xxxxxxxxxxxxxxx>
---
v6:
- reverted the XEN_DOMCTL_INTERFACE_VERSION bump
- reverted to uint32 for the guest handle
- explicit padding added to the domctl struct
- rewrote domain_set_llc_colors_domctl() to be more explicit
v5:
- added a new hypercall to set colors
- uint for the guest handle
v4:
- updated XEN_DOMCTL_INTERFACE_VERSION
---
 xen/common/domctl.c            | 11 +++++++++++
 xen/common/llc-coloring.c      | 25 +++++++++++++++++++++++++
 xen/include/public/domctl.h    |  9 +++++++++
 xen/include/xen/llc-coloring.h |  3 +++
 4 files changed, 48 insertions(+)

diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index f5a71ee5f7..b6867d0602 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -8,6 +8,7 @@
 
 #include <xen/types.h>
 #include <xen/lib.h>
+#include <xen/llc-coloring.h>
 #include <xen/err.h>
 #include <xen/mm.h>
 #include <xen/sched.h>
@@ -858,6 +859,16 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
u_domctl)
                 __HYPERVISOR_domctl, "h", u_domctl);
         break;
 
+    case XEN_DOMCTL_set_llc_colors:
+        if ( !llc_coloring_enabled )
+            break;
+
+        ret = domain_set_llc_colors_domctl(d, &op->u.set_llc_colors);
+        if ( ret == -EEXIST )
+            printk(XENLOG_ERR
+                   "Can't set LLC colors on an already created domain\n");
+        break;
+
     default:
         ret = arch_do_domctl(op, d, u_domctl);
         break;
diff --git a/xen/common/llc-coloring.c b/xen/common/llc-coloring.c
index 983de44a47..aaf0606c00 100644
--- a/xen/common/llc-coloring.c
+++ b/xen/common/llc-coloring.c
@@ -4,6 +4,7 @@
  *
  * Copyright (C) 2022 Xilinx Inc.
  */
+#include <xen/guest_access.h>
 #include <xen/keyhandler.h>
 #include <xen/llc-coloring.h>
 #include <xen/param.h>
@@ -229,6 +230,30 @@ int __init dom0_set_llc_colors(struct domain *d)
     return domain_check_colors(d);
 }
 
+int domain_set_llc_colors_domctl(struct domain *d,
+                                 const struct xen_domctl_set_llc_colors 
*config)
+{
+    unsigned int *colors;
+
+    if ( d->num_llc_colors )
+        return -EEXIST;
+
+    if ( !config->num_llc_colors )
+        return domain_set_default_colors(d);
+
+    colors = alloc_colors(config->num_llc_colors);
+    if ( !colors )
+        return -ENOMEM;
+
+    if ( copy_from_guest(colors, config->llc_colors, config->num_llc_colors) )
+        return -EFAULT;
+
+    d->llc_colors = colors;
+    d->num_llc_colors = config->num_llc_colors;
+
+    return domain_check_colors(d);
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
index a33f9ec32b..d090cdb2dd 100644
--- a/xen/include/public/domctl.h
+++ b/xen/include/public/domctl.h
@@ -1190,6 +1190,13 @@ struct xen_domctl_vmtrace_op {
 typedef struct xen_domctl_vmtrace_op xen_domctl_vmtrace_op_t;
 DEFINE_XEN_GUEST_HANDLE(xen_domctl_vmtrace_op_t);
 
+struct xen_domctl_set_llc_colors {
+    /* IN LLC coloring parameters */
+    uint32_t num_llc_colors;
+    uint32_t padding;
+    XEN_GUEST_HANDLE_64(uint32) llc_colors;
+};
+
 struct xen_domctl {
     uint32_t cmd;
 #define XEN_DOMCTL_createdomain                   1
@@ -1277,6 +1284,7 @@ struct xen_domctl {
 #define XEN_DOMCTL_vmtrace_op                    84
 #define XEN_DOMCTL_get_paging_mempool_size       85
 #define XEN_DOMCTL_set_paging_mempool_size       86
+#define XEN_DOMCTL_set_llc_colors                87
 #define XEN_DOMCTL_gdbsx_guestmemio            1000
 #define XEN_DOMCTL_gdbsx_pausevcpu             1001
 #define XEN_DOMCTL_gdbsx_unpausevcpu           1002
@@ -1339,6 +1347,7 @@ struct xen_domctl {
         struct xen_domctl_vuart_op          vuart_op;
         struct xen_domctl_vmtrace_op        vmtrace_op;
         struct xen_domctl_paging_mempool    paging_mempool;
+        struct xen_domctl_set_llc_colors    set_llc_colors;
         uint8_t                             pad[128];
     } u;
 };
diff --git a/xen/include/xen/llc-coloring.h b/xen/include/xen/llc-coloring.h
index 1a73080c98..a82081367f 100644
--- a/xen/include/xen/llc-coloring.h
+++ b/xen/include/xen/llc-coloring.h
@@ -28,6 +28,9 @@ unsigned int get_llc_way_size(void);
 void arch_llc_coloring_init(void);
 int dom0_set_llc_colors(struct domain *d);
 
+int domain_set_llc_colors_domctl(struct domain *d,
+                                 const struct xen_domctl_set_llc_colors 
*config);
+
 #endif /* __COLORING_H__ */
 
 /*
-- 
2.34.1