Commit eb5dfcb9 authored by Dave Jiang's avatar Dave Jiang Committed by Jason Gunthorpe
Browse files

cxl: Add support to handle user feature commands for set feature 

Add helper function to parse the user data from fwctl RPC ioctl and
send the parsed input parameters to cxl_set_feature() call.

Link: https://patch.msgid.link/r/20250307205648.1021626-6-dave.jiang@intel.com


Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Reviewed-by: default avatarLi Ming <ming.li@zohomail.com>
Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 5908f3ed

drivers/cxl/core/features.c

+144 −2
Original line number Diff line number Diff line
@@ -21,16 +21,21 @@ static const uuid_t cxl_exclusive_feats[] = { 
	CXL_FEAT_RANK_SPARING_UUID,

};



static bool is_cxl_feature_exclusive(struct cxl_feat_entry *entry)

static bool is_cxl_feature_exclusive_by_uuid(const uuid_t *uuid)

{

	for (int i = 0; i < ARRAY_SIZE(cxl_exclusive_feats); i++) {

		if (uuid_equal(&entry->uuid, &cxl_exclusive_feats[i]))

		if (uuid_equal(uuid, &cxl_exclusive_feats[i]))

			return true;

	}



	return false;

}



static bool is_cxl_feature_exclusive(struct cxl_feat_entry *entry)

{

	return is_cxl_feature_exclusive_by_uuid(&entry->uuid);

}



inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds)

{

	return cxlds->cxlfs;
@@ -350,6 +355,27 @@ static void cxlctl_close_uctx(struct fwctl_uctx *uctx) 
{

}



static struct cxl_feat_entry *

get_support_feature_info(struct cxl_features_state *cxlfs,

			 const struct fwctl_rpc_cxl *rpc_in)

{

	struct cxl_feat_entry *feat;

	const uuid_t *uuid;



	if (rpc_in->op_size < sizeof(uuid))

		return ERR_PTR(-EINVAL);



	uuid = &rpc_in->set_feat_in.uuid;



	for (int i = 0; i < cxlfs->entries->num_features; i++) {

		feat = &cxlfs->entries->ent[i];

		if (uuid_equal(uuid, &feat->uuid))

			return feat;

	}



	return ERR_PTR(-EINVAL);

}



static void *cxlctl_get_supported_features(struct cxl_features_state *cxlfs,

					   const struct fwctl_rpc_cxl *rpc_in,

					   size_t *out_len)
@@ -468,6 +494,116 @@ static void *cxlctl_get_feature(struct cxl_features_state *cxlfs, 
	return no_free_ptr(rpc_out);

}



static void *cxlctl_set_feature(struct cxl_features_state *cxlfs,

				const struct fwctl_rpc_cxl *rpc_in,

				size_t *out_len)

{

	struct cxl_mailbox *cxl_mbox = &cxlfs->cxlds->cxl_mbox;

	const struct cxl_mbox_set_feat_in *feat_in;

	size_t out_size, data_size;

	u16 offset, return_code;

	u32 flags;

	int rc;



	if (rpc_in->op_size <= sizeof(feat_in->hdr))

		return ERR_PTR(-EINVAL);



	feat_in = &rpc_in->set_feat_in;



	if (is_cxl_feature_exclusive_by_uuid(&feat_in->uuid))

		return ERR_PTR(-EPERM);



	offset = le16_to_cpu(feat_in->offset);

	flags = le32_to_cpu(feat_in->flags);

	out_size = *out_len;



	struct fwctl_rpc_cxl_out *rpc_out __free(kvfree) =

		kvzalloc(out_size, GFP_KERNEL);

	if (!rpc_out)

		return ERR_PTR(-ENOMEM);



	rpc_out->size = 0;



	data_size = rpc_in->op_size - sizeof(feat_in->hdr);

	rc = cxl_set_feature(cxl_mbox, &feat_in->uuid,

			     feat_in->version, feat_in->feat_data,

			     data_size, flags, offset, &return_code);

	if (rc) {

		rpc_out->retval = return_code;

		return no_free_ptr(rpc_out);

	}



	rpc_out->retval = CXL_MBOX_CMD_RC_SUCCESS;

	*out_len = sizeof(*rpc_out);



	return no_free_ptr(rpc_out);

}



static bool cxlctl_validate_set_features(struct cxl_features_state *cxlfs,

					 const struct fwctl_rpc_cxl *rpc_in,

					 enum fwctl_rpc_scope scope)

{

	u16 effects, imm_mask, reset_mask;

	struct cxl_feat_entry *feat;

	u32 flags;



	feat = get_support_feature_info(cxlfs, rpc_in);

	if (IS_ERR(feat))

		return false;



	/* Ensure that the attribute is changeable */

	flags = le32_to_cpu(feat->flags);

	if (!(flags & CXL_FEATURE_F_CHANGEABLE))

		return false;



	effects = le16_to_cpu(feat->effects);



	/*

	 * Reserved bits are set, rejecting since the effects is not

	 * comprehended by the driver.

	 */

	if (effects & CXL_CMD_EFFECTS_RESERVED) {

		dev_warn_once(cxlfs->cxlds->dev,

			      "Reserved bits set in the Feature effects field!\n");

		return false;

	}



	/* Currently no user background command support */

	if (effects & CXL_CMD_BACKGROUND)

		return false;



	/* Effects cause immediate change, highest security scope is needed */

	imm_mask = CXL_CMD_CONFIG_CHANGE_IMMEDIATE |

		   CXL_CMD_DATA_CHANGE_IMMEDIATE |

		   CXL_CMD_POLICY_CHANGE_IMMEDIATE |

		   CXL_CMD_LOG_CHANGE_IMMEDIATE;



	reset_mask = CXL_CMD_CONFIG_CHANGE_COLD_RESET |

		     CXL_CMD_CONFIG_CHANGE_CONV_RESET |

		     CXL_CMD_CONFIG_CHANGE_CXL_RESET;



	/* If no immediate or reset effect set, The hardware has a bug */

	if (!(effects & imm_mask) && !(effects & reset_mask))

		return false;



	/*

	 * If the Feature setting causes immediate configuration change

	 * then we need the full write permission policy.

	 */

	if (effects & imm_mask && scope >= FWCTL_RPC_DEBUG_WRITE_FULL)

		return true;



	/*

	 * If the Feature setting only causes configuration change

	 * after a reset, then the lesser level of write permission

	 * policy is ok.

	 */

	if (!(effects & imm_mask) && scope >= FWCTL_RPC_DEBUG_WRITE)

		return true;



	return false;

}



static bool cxlctl_validate_hw_command(struct cxl_features_state *cxlfs,

				       const struct fwctl_rpc_cxl *rpc_in,

				       enum fwctl_rpc_scope scope,
@@ -483,6 +619,10 @@ static bool cxlctl_validate_hw_command(struct cxl_features_state *cxlfs, 
		if (scope >= FWCTL_RPC_CONFIGURATION)

			return true;

		return false;

	case CXL_MBOX_OP_SET_FEATURE:

		if (cxl_mbox->feat_cap < CXL_FEATURES_RW)

			return false;

		return cxlctl_validate_set_features(cxlfs, rpc_in, scope);

	default:

		return false;

	}
@@ -497,6 +637,8 @@ static void *cxlctl_handle_commands(struct cxl_features_state *cxlfs, 
		return cxlctl_get_supported_features(cxlfs, rpc_in, out_len);

	case CXL_MBOX_OP_GET_FEATURE:

		return cxlctl_get_feature(cxlfs, rpc_in, out_len);

	case CXL_MBOX_OP_SET_FEATURE:

		return cxlctl_set_feature(cxlfs, rpc_in, out_len);

	default:

		return ERR_PTR(-EOPNOTSUPP);

	}

include/uapi/fwctl/cxl.h

+2 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
 * @reserved1: Reserved. Must be 0s.

 * @get_sup_feats_in: Get Supported Features input

 * @get_feat_in: Get Feature input

 * @set_feat_in: Set Feature input

 */

struct fwctl_rpc_cxl {

	__struct_group(fwctl_rpc_cxl_hdr, hdr, /* no attrs */,
@@ -30,6 +31,7 @@ struct fwctl_rpc_cxl { 
	union {

		struct cxl_mbox_get_sup_feats_in get_sup_feats_in;

		struct cxl_mbox_get_feat_in get_feat_in;

		struct cxl_mbox_set_feat_in set_feat_in;

	};

};