[Qemu-devel] [PATCH] ivshmem: add 64bit option

[Gerd Hoffmann]

This patch adds a "use64" property which will make the ivshmem driver
register a 64bit memory bar when set, so you have something to play with
when testing 64bit pci bits.  It also allows to have quite big shared
memory regions, like this:

[root@fedora ~]# lspci -vs1:1
01:01.0 RAM memory: Red Hat, Inc Device 1110
        Subsystem: Red Hat, Inc Device 1100
        Physical Slot: 1-1
        Flags: fast devsel
        Memory at fd400000 (32-bit, non-prefetchable) [disabled] [size=256]
        Memory at 8040000000 (64-bit, prefetchable) [size=1G]

[ v3: rebase & adapt to latest master ]
[ v2: default to on as suggested by avi,
      turn off for pc-$old using compat property ]

Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
---
 hw/ivshmem.c |   13 ++++++++++---
 hw/pc_piix.c |    4 ++++
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 05559b6..8a776e2 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -72,6 +72,8 @@ typedef struct IVShmemState {
     MemoryRegion ivshmem;
     MemoryRegion msix_bar;
     uint64_t ivshmem_size; /* size of shared memory region */
+    uint32_t ivshmem_attr;
+    uint32_t ivshmem_64bit;
     int shm_fd; /* shared memory file descriptor */
 
     Peer *peers;
@@ -344,7 +346,7 @@ static void create_shared_memory_BAR(IVShmemState *s, int 
fd) {
     memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 
     /* region for shared memory */
-    pci_register_bar(&s->dev, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
+    pci_register_bar(&s->dev, 2, s->ivshmem_attr, &s->bar);
 }
 
 static void close_guest_eventfds(IVShmemState *s, int posn)
@@ -693,6 +695,11 @@ static int pci_ivshmem_init(PCIDevice *dev)
                      &s->ivshmem_mmio);
 
     memory_region_init(&s->bar, "ivshmem-bar2-container", s->ivshmem_size);
+    s->ivshmem_attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
+        PCI_BASE_ADDRESS_MEM_PREFETCH;
+    if (s->ivshmem_64bit) {
+        s->ivshmem_attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
+    }
 
     if ((s->server_chr != NULL) &&
                         (strncmp(s->server_chr->filename, "unix:", 5) == 0)) {
@@ -718,8 +725,7 @@ static int pci_ivshmem_init(PCIDevice *dev)
         /* allocate/initialize space for interrupt handling */
         s->peers = g_malloc0(s->nb_peers * sizeof(Peer));
 
-        pci_register_bar(&s->dev, 2,
-                         PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
+        pci_register_bar(&s->dev, 2, s->ivshmem_attr, &s->bar);
 
         s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
 
@@ -791,6 +797,7 @@ static Property ivshmem_properties[] = {
     DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
     DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
     DEFINE_PROP_STRING("role", IVShmemState, role),
+    DEFINE_PROP_UINT32("use64", IVShmemState, ivshmem_64bit, 1),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index 0c0096f..5101f5d 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -375,6 +375,10 @@ static QEMUMachine pc_machine_v1_2 = {
             .driver   = "qxl",\
             .property = "vgamem_mb",\
             .value    = stringify(8),\
+        },{\
+            .driver   = "ivshmem",\
+            .property = "use64",\
+            .value    = "0",\
         }
 
 static QEMUMachine pc_machine_v1_1 = {
-- 
1.7.1