Merge tag 'vfio-v6.7-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Add support for "chunk mode" in the mlx5-vfio-pci variant driver,
   which allows both larger device image sizes for migration, beyond the
   previous 4GB limit, and also read-ahead support for improved
   migration performance (Yishai Hadas)

 - A new bus master control interface for the CDX bus driver where there
   is no in-band mechanism to toggle device DMA as there is through
   config space on PCI devices (Nipun Gupta)

 - Add explicit alignment directives to vfio data structures to reduce
   the chance of breaking 32-bit userspace. In most cases this is
   transparent and the remaining cases where data structures are padded
   work within the existing rules for extending data structures within
   vfio (Stefan Hajnoczi)

 - Resolve a bug in the cdx bus driver noted when compiled with clang
   where missing parenthesis result in the wrong operation (Nathan
   Chancellor)

 - Resolve errors reported by smatch for a function when dealing with
   invalid inputs (Alex Williamson)

 - Add migration support to the mtty vfio/mdev sample driver for testing
   and integration purposes, allowing CI of migration without specific
   hardware requirements. Also resolve many of the short- comings of
   this driver relative to implementation of the vfio interrupt ioctl
   along the way (Alex Williamson)

* tag 'vfio-v6.7-rc1' of https://github.com/awilliam/linux-vfio:
  vfio/mtty: Enable migration support
  vfio/mtty: Overhaul mtty interrupt handling
  vfio: Fix smatch errors in vfio_combine_iova_ranges()
  vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
  vfio/mlx5: Activate the chunk mode functionality
  vfio/mlx5: Add support for READING in chunk mode
  vfio/mlx5: Add support for SAVING in chunk mode
  vfio/mlx5: Pre-allocate chunks for the STOP_COPY phase
  vfio/mlx5: Rename some stuff to match chunk mode
  vfio/mlx5: Enable querying state size which is > 4GB
  vfio/mlx5: Refactor the SAVE callback to activate a work only upon an error
  vfio/mlx5: Wake up the reader post of disabling the SAVING migration file
  vfio: use __aligned_u64 in struct vfio_device_ioeventfd
  vfio: use __aligned_u64 in struct vfio_device_gfx_plane_info
  vfio: trivially use __aligned_u64 for ioctl structs
  vfio-cdx: add bus mastering device feature support
  vfio: add bus master feature to device feature ioctl
  cdx: add support for bus mastering

1 files changed, 58 insertions, 0 deletions

diff --git a/drivers/cdx/controller/mcdi_functions.c b/drivers/cdx/controller/mcdi_functions.c
index 0158f26533dd..fc82435d5dea 100644
--- a/drivers/cdx/controller/mcdi_functions.c
+++ b/drivers/cdx/controller/mcdi_functions.c
@@ -137,3 +137,61 @@ int cdx_mcdi_reset_device(struct cdx_mcdi *cdx, u8 bus_num, u8 dev_num)
 
 	return ret;
 }
+
+static int cdx_mcdi_ctrl_flag_get(struct cdx_mcdi *cdx, u8 bus_num,
+				  u8 dev_num, u32 *flags)
+{
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_CDX_DEVICE_CONTROL_GET_IN_LEN);
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_CDX_DEVICE_CONTROL_GET_OUT_LEN);
+	size_t outlen;
+	int ret;
+
+	MCDI_SET_DWORD(inbuf, CDX_DEVICE_CONTROL_GET_IN_BUS, bus_num);
+	MCDI_SET_DWORD(inbuf, CDX_DEVICE_CONTROL_GET_IN_DEVICE, dev_num);
+	ret = cdx_mcdi_rpc(cdx, MC_CMD_CDX_DEVICE_CONTROL_GET, inbuf,
+			   sizeof(inbuf), outbuf, sizeof(outbuf), &outlen);
+	if (ret)
+		return ret;
+
+	if (outlen != MC_CMD_CDX_DEVICE_CONTROL_GET_OUT_LEN)
+		return -EIO;
+
+	*flags = MCDI_DWORD(outbuf, CDX_DEVICE_CONTROL_GET_OUT_FLAGS);
+
+	return 0;
+}
+
+static int cdx_mcdi_ctrl_flag_set(struct cdx_mcdi *cdx, u8 bus_num,
+				  u8 dev_num, bool enable, int bit_pos)
+{
+	MCDI_DECLARE_BUF(inbuf, MC_CMD_CDX_DEVICE_CONTROL_SET_IN_LEN);
+	u32 flags;
+	int ret;
+
+	/*
+	 * Get flags and then set/reset bit at bit_pos according to
+	 * the input params.
+	 */
+	ret = cdx_mcdi_ctrl_flag_get(cdx, bus_num, dev_num, &flags);
+	if (ret)
+		return ret;
+
+	flags = flags & (u32)(~(BIT(bit_pos)));
+	if (enable)
+		flags |= (1 << bit_pos);
+
+	MCDI_SET_DWORD(inbuf, CDX_DEVICE_CONTROL_SET_IN_BUS, bus_num);
+	MCDI_SET_DWORD(inbuf, CDX_DEVICE_CONTROL_SET_IN_DEVICE, dev_num);
+	MCDI_SET_DWORD(inbuf, CDX_DEVICE_CONTROL_SET_IN_FLAGS, flags);
+	ret = cdx_mcdi_rpc(cdx, MC_CMD_CDX_DEVICE_CONTROL_SET, inbuf,
+			   sizeof(inbuf), NULL, 0, NULL);
+
+	return ret;
+}
+
+int cdx_mcdi_bus_master_enable(struct cdx_mcdi *cdx, u8 bus_num,
+			       u8 dev_num, bool enable)
+{
+	return cdx_mcdi_ctrl_flag_set(cdx, bus_num, dev_num, enable,
+			MC_CMD_CDX_DEVICE_CONTROL_SET_IN_BUS_MASTER_ENABLE_LBN);
+}