'etc/reserved-memory-end' will allow QEMU to tell BIOS where PCI
BARs mapping could safely start in high memory.
Allowing BIOS to start mapping 64-bit PCI BARs at address where it
wouldn't conflict with other mappings QEMU might place before it.
That permits QEMU to reserve extra address space before
64-bit PCI hole for memory hotplug.
Signed-off-by: Igor Mammedov <imamm...@redhat.com>
---
v2:
* disable 'etc/reserved-memory-end' for 1.7 and older machine types
---
hw/i386/pc.c | 27 +++++++++++++++++++++++++--
hw/i386/pc_piix.c | 1 +
hw/i386/pc_q35.c | 1 +
hw/pci-host/piix.c | 3 ++-
hw/pci-host/q35.c | 3 ++-
include/hw/i386/pc.h | 11 +++++++++--
6 files changed, 40 insertions(+), 6 deletions(-)
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 6c82ada..ba82c67 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1094,14 +1094,37 @@ PcGuestInfo *pc_guest_info_init(ram_addr_t
below_4g_mem_size,
}
/* setup pci memory address space mapping into system address space */
-void pc_pci_as_mapping_init(Object *owner, MemoryRegion *system_memory,
- MemoryRegion *pci_address_space)
+void pc_pci_as_mapping_init_1_7(Object *owner, MemoryRegion *system_memory,
+ MemoryRegion *pci_address_space,
+ uint64_t reserved_memory_end)
{
/* Set to lower priority than RAM */
memory_region_add_subregion_overlap(system_memory, 0x0,
pci_address_space, -1);
}
+static
+void pc_pci_as_mapping_init_1_8(Object *owner, MemoryRegion *system_memory,
+ MemoryRegion *pci_address_space,
+ uint64_t reserved_memory_end)
+{
+ uint64_t *val;
+ FWCfgState *fw_cfg = fw_cfg_find();
+ g_assert(fw_cfg);
+ /*
+ * Align address at 1G, this makes sure it can be exactly covered
+ * with a PAT entry even when using huge pages.
+ */
+ val = g_malloc(sizeof(*val));
+ *val = cpu_to_le64(ROUND_UP(reserved_memory_end, 0x1ULL << 30));
+ fw_cfg_add_file(fw_cfg, "etc/reserved-memory-end", val, sizeof(*val));
+
+ pc_pci_as_mapping_init_1_7(owner, system_memory, pci_address_space,
+ reserved_memory_end);
+}
+
+pc_pci_as_mapping_init_fn pc_pci_as_mapping_init = pc_pci_as_mapping_init_1_8;
+
void pc_acpi_init(const char *default_dsdt)
{
char *filename;
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 0456ab1..c0904f9 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -240,6 +240,7 @@ static void pc_init_pci(QEMUMachineInitArgs *args)
static void pc_compat_1_7(QEMUMachineInitArgs *args)
{
+ pc_pci_as_mapping_init = pc_pci_as_mapping_init_1_7;
}
static void pc_compat_1_6(QEMUMachineInitArgs *args)
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index b18e966..c165843 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -224,6 +224,7 @@ static void pc_q35_init(QEMUMachineInitArgs *args)
static void pc_compat_1_7(QEMUMachineInitArgs *args)
{
+ pc_pci_as_mapping_init = pc_pci_as_mapping_init_1_7;
}
static void pc_compat_1_6(QEMUMachineInitArgs *args)
diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index 5d4e290..16205e7 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -351,7 +351,8 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state,
/* setup pci memory mapping */
pc_pci_as_mapping_init(OBJECT(f), f->system_memory,
- f->pci_address_space);
+ f->pci_address_space,
+ 0x100000000ULL + above_4g_mem_size);
memory_region_init_alias(&f->smram_region, OBJECT(d), "smram-region",
f->pci_address_space, 0xa0000, 0x20000);
diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index d1792de..1293353 100644
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -353,7 +353,8 @@ static int mch_init(PCIDevice *d)
/* setup pci memory mapping */
pc_pci_as_mapping_init(OBJECT(mch), mch->system_memory,
- mch->pci_address_space);
+ mch->pci_address_space,
+ 0x100000000ULL + mch->above_4g_mem_size);
/* smram */
cpu_smm_register(&mch_set_smm, mch);
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 8b3be3c..bf1b168 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -129,8 +129,15 @@ PcGuestInfo *pc_guest_info_init(ram_addr_t
below_4g_mem_size,
#define DEFAULT_PCI_HOLE64_SIZE (~0x0ULL)
-void pc_pci_as_mapping_init(Object *owner, MemoryRegion *system_memory,
- MemoryRegion *pci_address_space);
+typedef
+void (*pc_pci_as_mapping_init_fn)(Object *owner, MemoryRegion *system_memory,
+ MemoryRegion *pci_address_space,
+ uint64_t reserved_memory_end);
+extern pc_pci_as_mapping_init_fn pc_pci_as_mapping_init;
+
+void pc_pci_as_mapping_init_1_7(Object *owner, MemoryRegion *system_memory,
+ MemoryRegion *pci_address_space,
+ uint64_t reserved_memory_end);
FWCfgState *pc_memory_init(MemoryRegion *system_memory,
const char *kernel_filename,
--
1.8.3.1
