[PULL 0/2] xen-virtio-1-tag

[PULL 0/2] xen-virtio-1-tag

[Stefano Stabellini]

The following changes since commit d1181d29370a4318a9f11ea92065bea6bb159f83:

  Merge tag 'pull-nbd-2023-07-19' of https://repo.or.cz/qemu/ericb into staging (2023-07-20 09:54:07 +0100)

are available in the Git repository at:

  https://gitlab.com/sstabellini/qemu.git xen-virtio-1-tag

for you to fetch changes up to 6bb48c66946dfbd653f06ad5f3fc957972333b56:

  xen_arm: Initialize RAM and add hi/low memory regions (2023-07-21 18:00:29 -0700)

----------------------------------------------------------------
Oleksandr Tyshchenko (2):
      xen_arm: Create virtio-mmio devices during initialization
      xen_arm: Initialize RAM and add hi/low memory regions

 hw/arm/xen_arm.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)

[PULL 1/2] xen_arm: Create virtio-mmio devices during initialization

[Stefano Stabellini]

From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

In order to use virtio backends we need to allocate virtio-mmio
parameters (irq and base) and register corresponding buses.

Use the constants defined in public header arch-arm.h to be
aligned with the toolstack. So the number of current supported
virtio-mmio devices is 10.

For the interrupts triggering use already existing on Arm
device-model hypercall.

The toolstack should then insert the same amount of device nodes
into guest device-tree.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
 hw/arm/xen_arm.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/hw/arm/xen_arm.c b/hw/arm/xen_arm.c
index 044093fec7..e700829654 100644
--- a/hw/arm/xen_arm.c
+++ b/hw/arm/xen_arm.c
@@ -26,6 +26,7 @@
 #include "qapi/qapi-commands-migration.h"
 #include "qapi/visitor.h"
 #include "hw/boards.h"
+#include "hw/irq.h"
 #include "hw/sysbus.h"
 #include "sysemu/block-backend.h"
 #include "sysemu/tpm_backend.h"
@@ -59,6 +60,38 @@ struct XenArmState {
     } cfg;
 };
 
+/*
+ * VIRTIO_MMIO_DEV_SIZE is imported from tools/libs/light/libxl_arm.c under Xen
+ * repository.
+ *
+ * Origin: git://xenbits.xen.org/xen.git 2128143c114c
+ */
+#define VIRTIO_MMIO_DEV_SIZE   0x200
+
+#define NR_VIRTIO_MMIO_DEVICES   \
+   (GUEST_VIRTIO_MMIO_SPI_LAST - GUEST_VIRTIO_MMIO_SPI_FIRST)
+
+static void xen_set_irq(void *opaque, int irq, int level)
+{
+    xendevicemodel_set_irq_level(xen_dmod, xen_domid, irq, level);
+}
+
+static void xen_create_virtio_mmio_devices(XenArmState *xam)
+{
+    int i;
+
+    for (i = 0; i < NR_VIRTIO_MMIO_DEVICES; i++) {
+        hwaddr base = GUEST_VIRTIO_MMIO_BASE + i * VIRTIO_MMIO_DEV_SIZE;
+        qemu_irq irq = qemu_allocate_irq(xen_set_irq, NULL,
+                                         GUEST_VIRTIO_MMIO_SPI_FIRST + i);
+
+        sysbus_create_simple("virtio-mmio", base, irq);
+
+        DPRINTF("Created virtio-mmio device %d: irq %d base 0x%lx\n",
+                i, GUEST_VIRTIO_MMIO_SPI_FIRST + i, base);
+    }
+}
+
 void arch_handle_ioreq(XenIOState *state, ioreq_t *req)
 {
     hw_error("Invalid ioreq type 0x%x\n", req->type);
@@ -110,6 +143,8 @@ static void xen_arm_init(MachineState *machine)
 
     xen_register_ioreq(xam->state, machine->smp.cpus, xen_memory_listener);
 
+    xen_create_virtio_mmio_devices(xam);
+
 #ifdef CONFIG_TPM
     if (xam->cfg.tpm_base_addr) {
         xen_enable_tpm(xam);
-- 
2.25.1

[PULL 2/2] xen_arm: Initialize RAM and add hi/low memory regions

[Stefano Stabellini]

From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

In order to use virtio backends we need to initialize RAM for the
xen-mapcache (which is responsible for mapping guest memory using foreign
mapping) to work. Calculate and add hi/low memory regions based on
machine->ram_size.

Use the constants defined in public header arch-arm.h to be aligned with the xen
toolstack.

While using this machine, the toolstack should then pass real ram_size using
"-m" arg. If "-m" is not given, create a QEMU machine without IOREQ and other
emulated devices like TPM and VIRTIO. This is done to keep this QEMU machine
usable for /etc/init.d/xencommons.

Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---
 hw/arm/xen_arm.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/hw/arm/xen_arm.c b/hw/arm/xen_arm.c
index e700829654..ec8de00cf5 100644
--- a/hw/arm/xen_arm.c
+++ b/hw/arm/xen_arm.c
@@ -60,6 +60,8 @@ struct XenArmState {
     } cfg;
 };
 
+static MemoryRegion ram_lo, ram_hi;
+
 /*
  * VIRTIO_MMIO_DEV_SIZE is imported from tools/libs/light/libxl_arm.c under Xen
  * repository.
@@ -92,6 +94,39 @@ static void xen_create_virtio_mmio_devices(XenArmState *xam)
     }
 }
 
+static void xen_init_ram(MachineState *machine)
+{
+    MemoryRegion *sysmem = get_system_memory();
+    ram_addr_t block_len, ram_size[GUEST_RAM_BANKS];
+
+    if (machine->ram_size <= GUEST_RAM0_SIZE) {
+        ram_size[0] = machine->ram_size;
+        ram_size[1] = 0;
+        block_len = GUEST_RAM0_BASE + ram_size[0];
+    } else {
+        ram_size[0] = GUEST_RAM0_SIZE;
+        ram_size[1] = machine->ram_size - GUEST_RAM0_SIZE;
+        block_len = GUEST_RAM1_BASE + ram_size[1];
+    }
+
+    memory_region_init_ram(&ram_memory, NULL, "xen.ram", block_len,
+                           &error_fatal);
+
+    memory_region_init_alias(&ram_lo, NULL, "xen.ram.lo", &ram_memory,
+                             GUEST_RAM0_BASE, ram_size[0]);
+    memory_region_add_subregion(sysmem, GUEST_RAM0_BASE, &ram_lo);
+    DPRINTF("Initialized region xen.ram.lo: base 0x%llx size 0x%lx\n",
+            GUEST_RAM0_BASE, ram_size[0]);
+
+    if (ram_size[1] > 0) {
+        memory_region_init_alias(&ram_hi, NULL, "xen.ram.hi", &ram_memory,
+                                 GUEST_RAM1_BASE, ram_size[1]);
+        memory_region_add_subregion(sysmem, GUEST_RAM1_BASE, &ram_hi);
+        DPRINTF("Initialized region xen.ram.hi: base 0x%llx size 0x%lx\n",
+                GUEST_RAM1_BASE, ram_size[1]);
+    }
+}
+
 void arch_handle_ioreq(XenIOState *state, ioreq_t *req)
 {
     hw_error("Invalid ioreq type 0x%x\n", req->type);
@@ -141,6 +176,14 @@ static void xen_arm_init(MachineState *machine)
 
     xam->state =  g_new0(XenIOState, 1);
 
+    if (machine->ram_size == 0) {
+        DPRINTF("ram_size not specified. QEMU machine started without IOREQ"
+                "(no emulated devices including Virtio)\n");
+        return;
+    }
+
+    xen_init_ram(machine);
+
     xen_register_ioreq(xam->state, machine->smp.cpus, xen_memory_listener);
 
     xen_create_virtio_mmio_devices(xam);
@@ -188,6 +231,8 @@ static void xen_arm_machine_class_init(ObjectClass *oc, void *data)
     mc->init = xen_arm_init;
     mc->max_cpus = 1;
     mc->default_machine_opts = "accel=xen";
+    /* Set explicitly here to make sure that real ram_size is passed */
+    mc->default_ram_size = 0;
 
 #ifdef CONFIG_TPM
     object_class_property_add(oc, "tpm-base-addr", "uint64_t",
-- 
2.25.1

Re: [PULL 0/2] xen-virtio-1-tag

[Peter Maydell]

On Sat, 22 Jul 2023 at 02:10, Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> The following changes since commit d1181d29370a4318a9f11ea92065bea6bb159f83:
>
>   Merge tag 'pull-nbd-2023-07-19' of https://repo.or.cz/qemu/ericb into staging (2023-07-20 09:54:07 +0100)
>
> are available in the Git repository at:
>
>   https://gitlab.com/sstabellini/qemu.git xen-virtio-1-tag
>
> for you to fetch changes up to 6bb48c66946dfbd653f06ad5f3fc957972333b56:
>
>   xen_arm: Initialize RAM and add hi/low memory regions (2023-07-21 18:00:29 -0700)
>
> ----------------------------------------------------------------
> Oleksandr Tyshchenko (2):
>       xen_arm: Create virtio-mmio devices during initialization
>       xen_arm: Initialize RAM and add hi/low memory regions
>
>  hw/arm/xen_arm.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 80 insertions(+)

Fails to build, multiple targets:

https://gitlab.com/qemu-project/qemu/-/jobs/4726472678
https://gitlab.com/qemu-project/qemu/-/jobs/4726472642
etc

../hw/arm/xen_arm.c: In function 'xen_set_irq':
../hw/arm/xen_arm.c:78:5: error: implicit declaration of function
'xendevicemodel_set_irq_level'; did you mean
'xendevicemodel_set_isa_irq_level'?
[-Werror=implicit-function-declaration]

../hw/arm/xen_arm.c:78:5: error: nested extern declaration of
'xendevicemodel_set_irq_level' [-Werror=nested-externs]
../hw/arm/xen_arm.c: In function 'xen_create_virtio_mmio_devices':
../hw/arm/xen_arm.c:74:5: error: 'GUEST_VIRTIO_MMIO_SPI_LAST'
undeclared (first use in this function)
74 | (GUEST_VIRTIO_MMIO_SPI_LAST - GUEST_VIRTIO_MMIO_SPI_FIRST)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~

and others.

thanks
-- PMM