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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2018, Intel Corporation. */3 4#include "ice_common.h"5#include "ice_vf_mbx.h"6 7/**8 * ice_aq_send_msg_to_vf9 * @hw: pointer to the hardware structure10 * @vfid: VF ID to send msg11 * @v_opcode: opcodes for VF-PF communication12 * @v_retval: return error code13 * @msg: pointer to the msg buffer14 * @msglen: msg length15 * @cd: pointer to command details16 *17 * Send message to VF driver (0x0802) using mailbox18 * queue and asynchronously sending message via19 * ice_sq_send_cmd() function20 */21int22ice_aq_send_msg_to_vf(struct ice_hw *hw, u16 vfid, u32 v_opcode, u32 v_retval,23		      u8 *msg, u16 msglen, struct ice_sq_cd *cd)24{25	struct ice_aqc_pf_vf_msg *cmd;26	struct ice_aq_desc desc;27 28	ice_fill_dflt_direct_cmd_desc(&desc, ice_mbx_opc_send_msg_to_vf);29 30	cmd = &desc.params.virt;31	cmd->id = cpu_to_le32(vfid);32 33	desc.cookie_high = cpu_to_le32(v_opcode);34	desc.cookie_low = cpu_to_le32(v_retval);35 36	if (msglen)37		desc.flags |= cpu_to_le16(ICE_AQ_FLAG_RD);38 39	return ice_sq_send_cmd(hw, &hw->mailboxq, &desc, msg, msglen, cd);40}41 42static const u32 ice_legacy_aq_to_vc_speed[] = {43	VIRTCHNL_LINK_SPEED_100MB,	/* BIT(0) */44	VIRTCHNL_LINK_SPEED_100MB,45	VIRTCHNL_LINK_SPEED_1GB,46	VIRTCHNL_LINK_SPEED_1GB,47	VIRTCHNL_LINK_SPEED_1GB,48	VIRTCHNL_LINK_SPEED_10GB,49	VIRTCHNL_LINK_SPEED_20GB,50	VIRTCHNL_LINK_SPEED_25GB,51	VIRTCHNL_LINK_SPEED_40GB,52	VIRTCHNL_LINK_SPEED_40GB,53	VIRTCHNL_LINK_SPEED_40GB,54};55 56/**57 * ice_conv_link_speed_to_virtchnl58 * @adv_link_support: determines the format of the returned link speed59 * @link_speed: variable containing the link_speed to be converted60 *61 * Convert link speed supported by HW to link speed supported by virtchnl.62 * If adv_link_support is true, then return link speed in Mbps. Else return63 * link speed as a VIRTCHNL_LINK_SPEED_* casted to a u32. Note that the caller64 * needs to cast back to an enum virtchnl_link_speed in the case where65 * adv_link_support is false, but when adv_link_support is true the caller can66 * expect the speed in Mbps.67 */68u32 ice_conv_link_speed_to_virtchnl(bool adv_link_support, u16 link_speed)69{70	/* convert a BIT() value into an array index */71	u32 index = fls(link_speed) - 1;72 73	if (adv_link_support)74		return ice_get_link_speed(index);75	else if (index < ARRAY_SIZE(ice_legacy_aq_to_vc_speed))76		/* Virtchnl speeds are not defined for every speed supported in77		 * the hardware. To maintain compatibility with older AVF78		 * drivers, while reporting the speed the new speed values are79		 * resolved to the closest known virtchnl speeds80		 */81		return ice_legacy_aq_to_vc_speed[index];82 83	return VIRTCHNL_LINK_SPEED_UNKNOWN;84}85 86/* The mailbox overflow detection algorithm helps to check if there87 * is a possibility of a malicious VF transmitting too many MBX messages to the88 * PF.89 * 1. The mailbox snapshot structure, ice_mbx_snapshot, is initialized during90 * driver initialization in ice_init_hw() using ice_mbx_init_snapshot().91 * The struct ice_mbx_snapshot helps to track and traverse a static window of92 * messages within the mailbox queue while looking for a malicious VF.93 *94 * 2. When the caller starts processing its mailbox queue in response to an95 * interrupt, the structure ice_mbx_snapshot is expected to be cleared before96 * the algorithm can be run for the first time for that interrupt. This97 * requires calling ice_mbx_reset_snapshot() as well as calling98 * ice_mbx_reset_vf_info() for each VF tracking structure.99 *100 * 3. For every message read by the caller from the MBX Queue, the caller must101 * call the detection algorithm's entry function ice_mbx_vf_state_handler().102 * Before every call to ice_mbx_vf_state_handler() the struct ice_mbx_data is103 * filled as it is required to be passed to the algorithm.104 *105 * 4. Every time a message is read from the MBX queue, a tracking structure106 * for the VF must be passed to the state handler. The boolean output107 * report_malvf from ice_mbx_vf_state_handler() serves as an indicator to the108 * caller whether it must report this VF as malicious or not.109 *110 * 5. When a VF is identified to be malicious, the caller can send a message111 * to the system administrator.112 *113 * 6. The PF is responsible for maintaining the struct ice_mbx_vf_info114 * structure for each VF. The PF should clear the VF tracking structure if the115 * VF is reset. When a VF is shut down and brought back up, we will then116 * assume that the new VF is not malicious and may report it again if we117 * detect it again.118 *119 * 7. The function ice_mbx_reset_snapshot() is called to reset the information120 * in ice_mbx_snapshot for every new mailbox interrupt handled.121 */122#define ICE_RQ_DATA_MASK(rq_data) ((rq_data) & PF_MBX_ARQH_ARQH_M)123/* Using the highest value for an unsigned 16-bit value 0xFFFF to indicate that124 * the max messages check must be ignored in the algorithm125 */126#define ICE_IGNORE_MAX_MSG_CNT	0xFFFF127 128/**129 * ice_mbx_reset_snapshot - Reset mailbox snapshot structure130 * @snap: pointer to the mailbox snapshot131 */132static void ice_mbx_reset_snapshot(struct ice_mbx_snapshot *snap)133{134	struct ice_mbx_vf_info *vf_info;135 136	/* Clear mbx_buf in the mailbox snaphot structure and setting the137	 * mailbox snapshot state to a new capture.138	 */139	memset(&snap->mbx_buf, 0, sizeof(snap->mbx_buf));140	snap->mbx_buf.state = ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT;141 142	/* Reset message counts for all VFs to zero */143	list_for_each_entry(vf_info, &snap->mbx_vf, list_entry)144		vf_info->msg_count = 0;145}146 147/**148 * ice_mbx_traverse - Pass through mailbox snapshot149 * @hw: pointer to the HW struct150 * @new_state: new algorithm state151 *152 * Traversing the mailbox static snapshot without checking153 * for malicious VFs.154 */155static void156ice_mbx_traverse(struct ice_hw *hw,157		 enum ice_mbx_snapshot_state *new_state)158{159	struct ice_mbx_snap_buffer_data *snap_buf;160	u32 num_iterations;161 162	snap_buf = &hw->mbx_snapshot.mbx_buf;163 164	/* As mailbox buffer is circular, applying a mask165	 * on the incremented iteration count.166	 */167	num_iterations = ICE_RQ_DATA_MASK(++snap_buf->num_iterations);168 169	/* Checking either of the below conditions to exit snapshot traversal:170	 * Condition-1: If the number of iterations in the mailbox is equal to171	 * the mailbox head which would indicate that we have reached the end172	 * of the static snapshot.173	 * Condition-2: If the maximum messages serviced in the mailbox for a174	 * given interrupt is the highest possible value then there is no need175	 * to check if the number of messages processed is equal to it. If not176	 * check if the number of messages processed is greater than or equal177	 * to the maximum number of mailbox entries serviced in current work item.178	 */179	if (num_iterations == snap_buf->head ||180	    (snap_buf->max_num_msgs_mbx < ICE_IGNORE_MAX_MSG_CNT &&181	     ++snap_buf->num_msg_proc >= snap_buf->max_num_msgs_mbx))182		*new_state = ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT;183}184 185/**186 * ice_mbx_detect_malvf - Detect malicious VF in snapshot187 * @hw: pointer to the HW struct188 * @vf_info: mailbox tracking structure for a VF189 * @new_state: new algorithm state190 * @is_malvf: boolean output to indicate if VF is malicious191 *192 * This function tracks the number of asynchronous messages193 * sent per VF and marks the VF as malicious if it exceeds194 * the permissible number of messages to send.195 */196static int197ice_mbx_detect_malvf(struct ice_hw *hw, struct ice_mbx_vf_info *vf_info,198		     enum ice_mbx_snapshot_state *new_state,199		     bool *is_malvf)200{201	/* increment the message count for this VF */202	vf_info->msg_count++;203 204	if (vf_info->msg_count >= ICE_ASYNC_VF_MSG_THRESHOLD)205		*is_malvf = true;206 207	/* continue to iterate through the mailbox snapshot */208	ice_mbx_traverse(hw, new_state);209 210	return 0;211}212 213/**214 * ice_mbx_vf_state_handler - Handle states of the overflow algorithm215 * @hw: pointer to the HW struct216 * @mbx_data: pointer to structure containing mailbox data217 * @vf_info: mailbox tracking structure for the VF in question218 * @report_malvf: boolean output to indicate whether VF should be reported219 *220 * The function serves as an entry point for the malicious VF221 * detection algorithm by handling the different states and state222 * transitions of the algorithm:223 * New snapshot: This state is entered when creating a new static224 * snapshot. The data from any previous mailbox snapshot is225 * cleared and a new capture of the mailbox head and tail is226 * logged. This will be the new static snapshot to detect227 * asynchronous messages sent by VFs. On capturing the snapshot228 * and depending on whether the number of pending messages in that229 * snapshot exceed the watermark value, the state machine enters230 * traverse or detect states.231 * Traverse: If pending message count is below watermark then iterate232 * through the snapshot without any action on VF.233 * Detect: If pending message count exceeds watermark traverse234 * the static snapshot and look for a malicious VF.235 */236int237ice_mbx_vf_state_handler(struct ice_hw *hw, struct ice_mbx_data *mbx_data,238			 struct ice_mbx_vf_info *vf_info, bool *report_malvf)239{240	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;241	struct ice_mbx_snap_buffer_data *snap_buf;242	struct ice_ctl_q_info *cq = &hw->mailboxq;243	enum ice_mbx_snapshot_state new_state;244	bool is_malvf = false;245	int status = 0;246 247	if (!report_malvf || !mbx_data || !vf_info)248		return -EINVAL;249 250	*report_malvf = false;251 252	/* When entering the mailbox state machine assume that the VF253	 * is not malicious until detected.254	 */255	 /* Checking if max messages allowed to be processed while servicing current256	  * interrupt is not less than the defined AVF message threshold.257	  */258	if (mbx_data->max_num_msgs_mbx <= ICE_ASYNC_VF_MSG_THRESHOLD)259		return -EINVAL;260 261	/* The watermark value should not be lesser than the threshold limit262	 * set for the number of asynchronous messages a VF can send to mailbox263	 * nor should it be greater than the maximum number of messages in the264	 * mailbox serviced in current interrupt.265	 */266	if (mbx_data->async_watermark_val < ICE_ASYNC_VF_MSG_THRESHOLD ||267	    mbx_data->async_watermark_val > mbx_data->max_num_msgs_mbx)268		return -EINVAL;269 270	new_state = ICE_MAL_VF_DETECT_STATE_INVALID;271	snap_buf = &snap->mbx_buf;272 273	switch (snap_buf->state) {274	case ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT:275		/* Clear any previously held data in mailbox snapshot structure. */276		ice_mbx_reset_snapshot(snap);277 278		/* Collect the pending ARQ count, number of messages processed and279		 * the maximum number of messages allowed to be processed from the280		 * Mailbox for current interrupt.281		 */282		snap_buf->num_pending_arq = mbx_data->num_pending_arq;283		snap_buf->num_msg_proc = mbx_data->num_msg_proc;284		snap_buf->max_num_msgs_mbx = mbx_data->max_num_msgs_mbx;285 286		/* Capture a new static snapshot of the mailbox by logging the287		 * head and tail of snapshot and set num_iterations to the tail288		 * value to mark the start of the iteration through the snapshot.289		 */290		snap_buf->head = ICE_RQ_DATA_MASK(cq->rq.next_to_clean +291						  mbx_data->num_pending_arq);292		snap_buf->tail = ICE_RQ_DATA_MASK(cq->rq.next_to_clean - 1);293		snap_buf->num_iterations = snap_buf->tail;294 295		/* Pending ARQ messages returned by ice_clean_rq_elem296		 * is the difference between the head and tail of the297		 * mailbox queue. Comparing this value against the watermark298		 * helps to check if we potentially have malicious VFs.299		 */300		if (snap_buf->num_pending_arq >=301		    mbx_data->async_watermark_val) {302			new_state = ICE_MAL_VF_DETECT_STATE_DETECT;303			status = ice_mbx_detect_malvf(hw, vf_info, &new_state, &is_malvf);304		} else {305			new_state = ICE_MAL_VF_DETECT_STATE_TRAVERSE;306			ice_mbx_traverse(hw, &new_state);307		}308		break;309 310	case ICE_MAL_VF_DETECT_STATE_TRAVERSE:311		new_state = ICE_MAL_VF_DETECT_STATE_TRAVERSE;312		ice_mbx_traverse(hw, &new_state);313		break;314 315	case ICE_MAL_VF_DETECT_STATE_DETECT:316		new_state = ICE_MAL_VF_DETECT_STATE_DETECT;317		status = ice_mbx_detect_malvf(hw, vf_info, &new_state, &is_malvf);318		break;319 320	default:321		new_state = ICE_MAL_VF_DETECT_STATE_INVALID;322		status = -EIO;323	}324 325	snap_buf->state = new_state;326 327	/* Only report VFs as malicious the first time we detect it */328	if (is_malvf && !vf_info->malicious) {329		vf_info->malicious = 1;330		*report_malvf = true;331	}332 333	return status;334}335 336/**337 * ice_mbx_clear_malvf - Clear VF mailbox info338 * @vf_info: the mailbox tracking structure for a VF339 *340 * In case of a VF reset, this function shall be called to clear the VF's341 * current mailbox tracking state.342 */343void ice_mbx_clear_malvf(struct ice_mbx_vf_info *vf_info)344{345	vf_info->malicious = 0;346	vf_info->msg_count = 0;347}348 349/**350 * ice_mbx_init_vf_info - Initialize a new VF mailbox tracking info351 * @hw: pointer to the hardware structure352 * @vf_info: the mailbox tracking info structure for a VF353 *354 * Initialize a VF mailbox tracking info structure and insert it into the355 * snapshot list.356 *357 * If you remove the VF, you must also delete the associated VF info structure358 * from the linked list.359 */360void ice_mbx_init_vf_info(struct ice_hw *hw, struct ice_mbx_vf_info *vf_info)361{362	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;363 364	ice_mbx_clear_malvf(vf_info);365	list_add(&vf_info->list_entry, &snap->mbx_vf);366}367 368/**369 * ice_mbx_init_snapshot - Initialize mailbox snapshot data370 * @hw: pointer to the hardware structure371 *372 * Clear the mailbox snapshot structure and initialize the VF mailbox list.373 */374void ice_mbx_init_snapshot(struct ice_hw *hw)375{376	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;377 378	INIT_LIST_HEAD(&snap->mbx_vf);379	ice_mbx_reset_snapshot(snap);380}381