Finalize the series by advertising VDUSE API v1 support to userspace. Now that all required infrastructure for v1 (ASIDs, VQ groups, update_iotlb_v2) is in place, VDUSE devices can opt in to the new features.
Assume API version 0 if the VDUSE instance does not call VDUSE_GET_API_VERSION to maintain compatibility. Signed-off-by: Eugenio Pérez <[email protected]> --- v12: * Assume API version 0 by default if the VDUSE instance does not ask (Jason). --- drivers/vdpa/vdpa_user/vduse_dev.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 2727c0c26003..73d1d517dc6c 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -52,6 +52,15 @@ #define IRQ_UNBOUND -1 +/* + * VDUSE instance have not asked the vduse API version, so assume 0. + * + * Old devices may not ask for the device version and assume it is 0. Keep + * this value for these. From the moment the VDUSE instance ask for the + * version, convert to the latests supported one and continue regular flow + */ +#define VDUSE_API_VERSION_NOT_ASKED U64_MAX + struct vduse_virtqueue { u16 index; u16 num_max; @@ -2153,6 +2162,8 @@ static long vduse_ioctl(struct file *file, unsigned int cmd, mutex_lock(&vduse_lock); switch (cmd) { case VDUSE_GET_API_VERSION: + if (control->api_version == VDUSE_API_VERSION_NOT_ASKED) + control->api_version = VDUSE_API_VERSION_1; ret = put_user(control->api_version, (u64 __user *)argp); break; case VDUSE_SET_API_VERSION: { @@ -2163,7 +2174,7 @@ static long vduse_ioctl(struct file *file, unsigned int cmd, break; ret = -EINVAL; - if (api_version > VDUSE_API_VERSION) + if (api_version > VDUSE_API_VERSION_1) break; ret = 0; @@ -2180,6 +2191,8 @@ static long vduse_ioctl(struct file *file, unsigned int cmd, break; ret = -EINVAL; + if (control->api_version == VDUSE_API_VERSION_NOT_ASKED) + control->api_version = VDUSE_API_VERSION; if (!vduse_validate_config(&config, control->api_version)) break; @@ -2230,7 +2243,7 @@ static int vduse_open(struct inode *inode, struct file *file) if (!control) return -ENOMEM; - control->api_version = VDUSE_API_VERSION; + control->api_version = VDUSE_API_VERSION_NOT_ASKED; file->private_data = control; return 0; -- 2.52.0
