[Qemu-devel] [PATCH v1] xenpt: Properly handle 64-bit bar with more than 4G size

[Feng Wu <feng.wu@intel.com>]

This patch corrects a logic error when handling 64-bt bar with
more than 4G size.

With 64-bit Bar, it has two items in PCIDevice: io_regions[x]
and io_regions[x+1], io_regions[x] has all the informations for
this BAR, while io_regions[x+1] contains nothing, so we need to
get the size from io_regions[x] when handling XEN_PT_BAR_FLAG_UPPER.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
I cannot test this patch sicne I don't have such a device, if
someone have it, it would be highly appreicated if he can help
to verfiy this patch.

 hw/xen/xen_pt_config_init.c |   22 +++-------------------
 1 files changed, 3 insertions(+), 19 deletions(-)

diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c
index dd37be3..6fcef66 100644
--- a/hw/xen/xen_pt_config_init.c
+++ b/hw/xen/xen_pt_config_init.c
@@ -326,23 +326,6 @@ static int xen_pt_cmd_reg_write(XenPCIPassthroughState *s, XenPTReg *cfg_entry,
 #define XEN_PT_BAR_IO_RO_MASK     0x00000003  /* BAR ReadOnly mask(I/O) */
 #define XEN_PT_BAR_IO_EMU_MASK    0xFFFFFFFC  /* BAR emul mask(I/O) */
 
-static bool is_64bit_bar(PCIIORegion *r)
-{
-    return !!(r->type & PCI_BASE_ADDRESS_MEM_TYPE_64);
-}
-
-static uint64_t xen_pt_get_bar_size(PCIIORegion *r)
-{
-    if (is_64bit_bar(r)) {
-        uint64_t size64;
-        size64 = (r + 1)->size;
-        size64 <<= 32;
-        size64 += r->size;
-        return size64;
-    }
-    return r->size;
-}
-
 static XenPTBarFlag xen_pt_bar_reg_parse(XenPCIPassthroughState *s,
                                          int index)
 {
@@ -365,7 +348,7 @@ static XenPTBarFlag xen_pt_bar_reg_parse(XenPCIPassthroughState *s,
 
     /* check unused BAR */
     r = &d->io_regions[index];
-    if (!xen_pt_get_bar_size(r)) {
+    if (r->size == 0) {
         return XEN_PT_BAR_FLAG_UNUSED;
     }
 
@@ -491,8 +474,9 @@ static int xen_pt_bar_reg_write(XenPCIPassthroughState *s, XenPTReg *cfg_entry,
         bar_ro_mask = XEN_PT_BAR_IO_RO_MASK | (r_size - 1);
         break;
     case XEN_PT_BAR_FLAG_UPPER:
+        r = &d->io_regions[index-1];
         bar_emu_mask = XEN_PT_BAR_ALLF;
-        bar_ro_mask = r_size ? r_size - 1 : 0;
+        bar_ro_mask = (r->size - 1) >> 32;
         break;
     default:
         break;
-- 
1.7.1