Commit d97fe8ee authored by Alison Schofield's avatar Alison Schofield Committed by Dan Williams
Browse files

cxl/mbox: Make handle_mailbox_cmd_from_user() use a mbox param 



Previously, handle_mailbox_cmd_from_user(), constructed the mailbox
command and dispatched it to the hardware. The construction work
has moved to the validation path.

handle_mailbox_cmd_from_user() now expects a fully validated
mbox param. Make it's caller, cxl_send_cmd(), deliver it. Update
the comments and dereferencing of the new mbox parameter.

Signed-off-by: default avatarAlison Schofield <alison.schofield@intel.com>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/77050ba512d6c30eccf7505467509e460dd325a0.1648687552.git.alison.schofield@intel.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 82b8ba29

drivers/cxl/core/mbox.c

+17 −27
Original line number Diff line number Diff line
@@ -423,8 +423,7 @@ int cxl_query_cmd(struct cxl_memdev *cxlmd, 
/**

 * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace.

 * @cxlds: The device data for the operation

 * @cmd: The validated command.

 * @in_payload: Pointer to userspace's input payload.

 * @mbox_cmd: The validated mailbox command.

 * @out_payload: Pointer to userspace's output payload.

 * @size_out: (Input) Max payload size to copy out.

 *            (Output) Payload size hardware generated.
@@ -439,35 +438,27 @@ int cxl_query_cmd(struct cxl_memdev *cxlmd, 
 *  * %-EINTR	- Mailbox acquisition interrupted.

 *  * %-EXXX	- Transaction level failures.

 *

 * Creates the appropriate mailbox command and dispatches it on behalf of a

 * userspace request. The input and output payloads are copied between

 * userspace.

 * Dispatches a mailbox command on behalf of a userspace request.

 * The output payload is copied to userspace.

 *

 * See cxl_send_cmd().

 */

static int handle_mailbox_cmd_from_user(struct cxl_dev_state *cxlds,

					const struct cxl_mem_command *cmd,

					u64 in_payload, u64 out_payload,

					s32 *size_out, u32 *retval)

					struct cxl_mbox_cmd *mbox_cmd,

					u64 out_payload, s32 *size_out,

					u32 *retval)

{

	struct device *dev = cxlds->dev;

	struct cxl_mbox_cmd mbox_cmd;

	int rc;



	rc = cxl_mbox_cmd_ctor(&mbox_cmd, cxlds, cmd->opcode,

			       cmd->info.size_in, cmd->info.size_out,

			       in_payload);

	if (rc)

		return rc;



	dev_dbg(dev,

		"Submitting %s command for user\n"

		"\topcode: %x\n"

		"\tsize: %zx\n",

		cxl_mem_opcode_to_name(mbox_cmd.opcode),

		mbox_cmd.opcode, mbox_cmd.size_in);

		cxl_mem_opcode_to_name(mbox_cmd->opcode),

		mbox_cmd->opcode, mbox_cmd->size_in);



	rc = cxlds->mbox_send(cxlds, &mbox_cmd);

	rc = cxlds->mbox_send(cxlds, mbox_cmd);

	if (rc)

		goto out;
@@ -476,21 +467,21 @@ static int handle_mailbox_cmd_from_user(struct cxl_dev_state *cxlds, 
	 * to userspace. While the payload may have written more output than

	 * this it will have to be ignored.

	 */

	if (mbox_cmd.size_out) {

		dev_WARN_ONCE(dev, mbox_cmd.size_out > *size_out,

	if (mbox_cmd->size_out) {

		dev_WARN_ONCE(dev, mbox_cmd->size_out > *size_out,

			      "Invalid return size\n");

		if (copy_to_user(u64_to_user_ptr(out_payload),

				 mbox_cmd.payload_out, mbox_cmd.size_out)) {

				 mbox_cmd->payload_out, mbox_cmd->size_out)) {

			rc = -EFAULT;

			goto out;

		}

	}



	*size_out = mbox_cmd.size_out;

	*retval = mbox_cmd.return_code;

	*size_out = mbox_cmd->size_out;

	*retval = mbox_cmd->return_code;



out:

	cxl_mbox_cmd_dtor(&mbox_cmd);

	cxl_mbox_cmd_dtor(mbox_cmd);

	return rc;

}
@@ -512,9 +503,8 @@ int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s) 
	if (rc)

		return rc;



	rc = handle_mailbox_cmd_from_user(cxlds, &c, send.in.payload,

					  send.out.payload, &send.out.size,

					  &send.retval);

	rc = handle_mailbox_cmd_from_user(cxlds, &mbox_cmd, send.out.payload,

					  &send.out.size, &send.retval);

	if (rc)

		return rc;