On 3.03.2025 07:42, Cédric Le Goater wrote:
On 3/2/25 14:00, Avihai Horon wrote:
On 19/02/2025 22:34, Maciej S. Szmigiero wrote:
External email: Use caution opening links or attachments
From: "Maciej S. Szmigiero" <maciej.szmigi...@oracle.com>
Add VFIOStateBuffer(s) types and the associated methods.
These store received device state buffers and config state waiting to get
loaded into the device.
Signed-off-by: Maciej S. Szmigiero <maciej.szmigi...@oracle.com>
---
hw/vfio/migration-multifd.c | 54 +++++++++++++++++++++++++++++++++++++
1 file changed, 54 insertions(+)
diff --git a/hw/vfio/migration-multifd.c b/hw/vfio/migration-multifd.c
index 0c3185a26242..760b110a39b9 100644
--- a/hw/vfio/migration-multifd.c
+++ b/hw/vfio/migration-multifd.c
@@ -29,3 +29,57 @@ typedef struct VFIODeviceStatePacket {
uint32_t flags;
uint8_t data[0];
} QEMU_PACKED VFIODeviceStatePacket;
+
+/* type safety */
+typedef struct VFIOStateBuffers {
+ GArray *array;
+} VFIOStateBuffers;
+
+typedef struct VFIOStateBuffer {
+ bool is_present;
+ char *data;
+ size_t len;
+} VFIOStateBuffer;
+
+static void vfio_state_buffer_clear(gpointer data)
+{
+ VFIOStateBuffer *lb = data;
+
+ if (!lb->is_present) {
+ return;
+ }
+
+ g_clear_pointer(&lb->data, g_free);
+ lb->is_present = false;
+}
+
+static void vfio_state_buffers_init(VFIOStateBuffers *bufs)
+{
+ bufs->array = g_array_new(FALSE, TRUE, sizeof(VFIOStateBuffer));
+ g_array_set_clear_func(bufs->array, vfio_state_buffer_clear);
+}
+
+static void vfio_state_buffers_destroy(VFIOStateBuffers *bufs)
+{
+ g_clear_pointer(&bufs->array, g_array_unref);
+}
+
+static void vfio_state_buffers_assert_init(VFIOStateBuffers *bufs)
+{
+ assert(bufs->array);
+}
+
+static guint vfio_state_buffers_size_get(VFIOStateBuffers *bufs)
+{
+ return bufs->array->len;
+}
+
+static void vfio_state_buffers_size_set(VFIOStateBuffers *bufs, guint size)
+{
+ g_array_set_size(bufs->array, size);
+}
+
+static VFIOStateBuffer *vfio_state_buffers_at(VFIOStateBuffers *bufs, guint
idx)
+{
+ return &g_array_index(bufs->array, VFIOStateBuffer, idx);
+}
This patch breaks compilation as non of the functions are used, e.g.: error: ‘vfio_state_buffers_init’ defined but not used I can think of three options to solve it: 1. Move these functions to their own file and export them, e.g., hw/vfio/state-buffer.{c,h}. But this seems like an overkill for such a small API. 2. Add __attribute__((unused)) tags and remove them in patch #26 where the functions are actually used. A bit ugly.
3. Squash this patch into patch #26. I prefer option 3 as this is a small API
closely related to patch #26 (and patch #26 will still remain rather small).
I vote for option 3 too.
Merged this patch into the "received buffers queuing" one (#26) now.
vfio_state_buffers_init is only called once, it's 2 lines,
it could be merged in vfio_multifd_new() too.
Most of these helpers are even shorter (1 line), but the whole
point of them is to abstract the GArray rather than open-code
these accesses.
This was discussed two versions ago:
https://lore.kernel.org/qemu-devel/9106d15e-3ff5-4d42-880d-0de70a4ca...@maciej.szmigiero.name/
Thanks,
C.
Thanks,
Maciej
