x86/xen: fix memory setup for PVH dom0

Since af06d66ee32b (x86: fix setup of PVH Dom0 memory map) in Xen, PVH
dom0 need only use the memory memory provided by Xen which has already
setup all the correct holes.

xen_memory_setup() then ends up being trivial for a PVH guest so
introduce a new function (xen_auto_xlated_memory_setup()).

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Roger Pau Monné <roger.pau@citrix.com>

3 files changed, 34 insertions, 1 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 662bdcbbbd18..3123d1f74415 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1537,7 +1537,10 @@ asmlinkage void __init xen_start_kernel(void)
         if (!xen_pvh_domain())
                 pv_cpu_ops = xen_cpu_ops;
 
-        x86_init.resources.memory_setup = xen_memory_setup;
+        if (xen_feature(XENFEAT_auto_translated_physmap))
+                x86_init.resources.memory_setup = xen_auto_xlated_memory_setup;
+        else
+                x86_init.resources.memory_setup = xen_memory_setup;
         x86_init.oem.arch_setup = xen_arch_setup;
         x86_init.oem.banner = xen_banner;
 
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 210426a26cc0..37cfbfacd59a 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -518,6 +518,35 @@ char * __init xen_memory_setup(void)
 }
 
 /*
+ * Machine specific memory setup for auto-translated guests.
+ */
+char * __init xen_auto_xlated_memory_setup(void)
+{
+        static struct e820entry map[E820MAX] __initdata;
+
+        struct xen_memory_map memmap;
+        int i;
+        int rc;
+
+        memmap.nr_entries = E820MAX;
+        set_xen_guest_handle(memmap.buffer, map);
+
+        rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap);
+        if (rc < 0)
+                panic("No memory map (%d)\n", rc);
+
+        sanitize_e820_map(map, ARRAY_SIZE(map), &memmap.nr_entries);
+
+        for (i = 0; i < memmap.nr_entries; i++)
+                e820_add_region(map[i].addr, map[i].size, map[i].type);
+
+        memblock_reserve(__pa(xen_start_info->mfn_list),
+                         xen_start_info->pt_base - xen_start_info->mfn_list);
+
+        return "Xen";
+}
+
+/*
  * Set the bit indicating "nosegneg" library variants should be used.
  * We only need to bother in pure 32-bit mode; compat 32-bit processes
  * can have un-truncated segments, so wrapping around is allowed.
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index c834d4b231f0..97d87659f779 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -36,6 +36,7 @@ void xen_mm_unpin_all(void);
 void xen_set_pat(u64);
 
 char * __init xen_memory_setup(void);
+char * xen_auto_xlated_memory_setup(void);
 void __init xen_arch_setup(void);
 void xen_enable_sysenter(void);
 void xen_enable_syscall(void);