The reset function lookup happens on vfio-platform probe. The reset module load is requested and a reference to the function symbol is hold. The reference is released on vfio-platform remove.
Signed-off-by: Eric Auger <[email protected]> --- v1 -> v2: - [get,put]_reset now is called once on probe/remove - use request_module to automatically load the reset module that matches the compatibility string - lookup table is used instead of list - remove registration mechanism: reset function name is stored in the lookup table. - use device_property_read_string instead of device_property_read_string_array --- drivers/vfio/platform/vfio_platform_common.c | 48 +++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index 995929b..d474d6a 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -31,6 +31,47 @@ static const struct vfio_platform_reset_combo reset_lookup_table[] = { }, }; +static int vfio_platform_get_reset(struct vfio_platform_device *vdev, + struct device *dev) +{ + const char *compat; + const struct vfio_platform_reset_combo *iter = reset_lookup_table; + int (*reset)(struct vfio_platform_device *); + int ret; + + vdev->type = VFIO_PLATFORM_RESET_TYPE_MAX; + ret = device_property_read_string(dev, "compatible", &compat); + if (ret) + return ret; + + while (iter->type < VFIO_PLATFORM_RESET_TYPE_MAX) { + if (!strcmp(iter->compat, compat)) { + request_module(iter->module_name); + reset = __symbol_get(iter->reset_function_name); + if (reset) { + vdev->type = iter->type; + vdev->reset = reset; + return 0; + } + } + iter++; + } + return -1; +} + +static void vfio_platform_put_reset(struct vfio_platform_device *vdev) +{ + const struct vfio_platform_reset_combo *iter = reset_lookup_table; + + while (iter->type < VFIO_PLATFORM_RESET_TYPE_MAX) { + if (iter->type == vdev->type) { + __symbol_put(iter->reset_function_name); + return; + } + iter++; + } +} + static int vfio_platform_regions_init(struct vfio_platform_device *vdev) { int cnt = 0, i; @@ -519,6 +560,8 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, return ret; } + vfio_platform_get_reset(vdev, dev); + mutex_init(&vdev->igate); return 0; @@ -530,8 +573,11 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev) struct vfio_platform_device *vdev; vdev = vfio_del_group_dev(dev); - if (vdev) + + if (vdev) { + vfio_platform_put_reset(vdev); iommu_group_put(dev->iommu_group); + } return vdev; } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
