[RFC PATCH] virt: tdx-guest: Remove quote generation via ioctl

[Nikolay Borisov <nik.borisov@suse.com>]

When this driver got merged initially there was no widely agreed upon
interface how the quote generation interface will work so having an
ioctl made sense. However, there's now a vendor-neutral interface via
configfs. Just remove the old ioctl interface and leave only the the
configfs one.

Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
---

I think it's better to remove the legacy interface now, before there's been a
wide adoption of it, cementing it as an ABI of sorts.

 drivers/virt/coco/tdx-guest/tdx-guest.c | 75 +------------------------
 1 file changed, 2 insertions(+), 73 deletions(-)

diff --git a/drivers/virt/coco/tdx-guest/tdx-guest.c b/drivers/virt/coco/tdx-guest/tdx-guest.c
index 1253bf76b570..1642a0f70333 100644
--- a/drivers/virt/coco/tdx-guest/tdx-guest.c
+++ b/drivers/virt/coco/tdx-guest/tdx-guest.c
@@ -66,41 +66,6 @@ static DEFINE_MUTEX(quote_lock);
  */
 static u32 getquote_timeout = 30;

-static long tdx_get_report0(struct tdx_report_req __user *req)
-{
-	u8 *reportdata, *tdreport;
-	long ret;
-
-	reportdata = kmalloc(TDX_REPORTDATA_LEN, GFP_KERNEL);
-	if (!reportdata)
-		return -ENOMEM;
-
-	tdreport = kzalloc(TDX_REPORT_LEN, GFP_KERNEL);
-	if (!tdreport) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	if (copy_from_user(reportdata, req->reportdata, TDX_REPORTDATA_LEN)) {
-		ret = -EFAULT;
-		goto out;
-	}
-
-	/* Generate TDREPORT0 using "TDG.MR.REPORT" TDCALL */
-	ret = tdx_mcall_get_report0(reportdata, tdreport);
-	if (ret)
-		goto out;
-
-	if (copy_to_user(req->tdreport, tdreport, TDX_REPORT_LEN))
-		ret = -EFAULT;
-
-out:
-	kfree(reportdata);
-	kfree(tdreport);
-
-	return ret;
-}
-
 static void free_quote_buf(void *buf)
 {
 	size_t len = PAGE_ALIGN(GET_QUOTE_BUF_SIZE);
@@ -249,29 +214,6 @@ static int tdx_report_new(struct tsm_report *report, void *data)
 	return ret;
 }

-static long tdx_guest_ioctl(struct file *file, unsigned int cmd,
-			    unsigned long arg)
-{
-	switch (cmd) {
-	case TDX_CMD_GET_REPORT0:
-		return tdx_get_report0((struct tdx_report_req __user *)arg);
-	default:
-		return -ENOTTY;
-	}
-}
-
-static const struct file_operations tdx_guest_fops = {
-	.owner = THIS_MODULE,
-	.unlocked_ioctl = tdx_guest_ioctl,
-	.llseek = no_llseek,
-};
-
-static struct miscdevice tdx_misc_dev = {
-	.name = KBUILD_MODNAME,
-	.minor = MISC_DYNAMIC_MINOR,
-	.fops = &tdx_guest_fops,
-};
-
 static const struct x86_cpu_id tdx_guest_ids[] = {
 	X86_MATCH_FEATURE(X86_FEATURE_TDX_GUEST, NULL),
 	{}
@@ -290,27 +232,15 @@ static int __init tdx_guest_init(void)
 	if (!x86_match_cpu(tdx_guest_ids))
 		return -ENODEV;

-	ret = misc_register(&tdx_misc_dev);
-	if (ret)
-		return ret;
-
 	quote_data = alloc_quote_buf();
 	if (!quote_data) {
 		pr_err("Failed to allocate Quote buffer\n");
-		ret = -ENOMEM;
-		goto free_misc;
+		return -ENOMEM;
 	}

 	ret = tsm_register(&tdx_tsm_ops, NULL, NULL);
 	if (ret)
-		goto free_quote;
-
-	return 0;
-
-free_quote:
-	free_quote_buf(quote_data);
-free_misc:
-	misc_deregister(&tdx_misc_dev);
+		free_quote_buf(quote_data);

 	return ret;
 }
@@ -320,7 +250,6 @@ static void __exit tdx_guest_exit(void)
 {
 	tsm_unregister(&tdx_tsm_ops);
 	free_quote_buf(quote_data);
-	misc_deregister(&tdx_misc_dev);
 }
 module_exit(tdx_guest_exit);

--
2.34.1