1 files changed, 380 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_vf_mbx.c b/drivers/net/ethernet/intel/ice/ice_vf_mbx.c
new file mode 100644
index 000000000..40cb4ba07
--- /dev/null
+++ b/drivers/net/ethernet/intel/ice/ice_vf_mbx.c
@@ -0,0 +1,380 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2018, Intel Corporation. */
+
+#include "ice_common.h"
+#include "ice_vf_mbx.h"
+
+/**
+ * ice_aq_send_msg_to_vf
+ * @hw: pointer to the hardware structure
+ * @vfid: VF ID to send msg
+ * @v_opcode: opcodes for VF-PF communication
+ * @v_retval: return error code
+ * @msg: pointer to the msg buffer
+ * @msglen: msg length
+ * @cd: pointer to command details
+ *
+ * Send message to VF driver (0x0802) using mailbox
+ * queue and asynchronously sending message via
+ * ice_sq_send_cmd() function
+ */
+int
+ice_aq_send_msg_to_vf(struct ice_hw *hw, u16 vfid, u32 v_opcode, u32 v_retval,
+		      u8 *msg, u16 msglen, struct ice_sq_cd *cd)
+{
+	struct ice_aqc_pf_vf_msg *cmd;
+	struct ice_aq_desc desc;
+
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_mbx_opc_send_msg_to_vf);
+
+	cmd = &desc.params.virt;
+	cmd->id = cpu_to_le32(vfid);
+
+	desc.cookie_high = cpu_to_le32(v_opcode);
+	desc.cookie_low = cpu_to_le32(v_retval);
+
+	if (msglen)
+		desc.flags |= cpu_to_le16(ICE_AQ_FLAG_RD);
+
+	return ice_sq_send_cmd(hw, &hw->mailboxq, &desc, msg, msglen, cd);
+}
+
+static const u32 ice_legacy_aq_to_vc_speed[] = {
+	VIRTCHNL_LINK_SPEED_100MB,	/* BIT(0) */
+	VIRTCHNL_LINK_SPEED_100MB,
+	VIRTCHNL_LINK_SPEED_1GB,
+	VIRTCHNL_LINK_SPEED_1GB,
+	VIRTCHNL_LINK_SPEED_1GB,
+	VIRTCHNL_LINK_SPEED_10GB,
+	VIRTCHNL_LINK_SPEED_20GB,
+	VIRTCHNL_LINK_SPEED_25GB,
+	VIRTCHNL_LINK_SPEED_40GB,
+	VIRTCHNL_LINK_SPEED_40GB,
+	VIRTCHNL_LINK_SPEED_40GB,
+};
+
+/**
+ * ice_conv_link_speed_to_virtchnl
+ * @adv_link_support: determines the format of the returned link speed
+ * @link_speed: variable containing the link_speed to be converted
+ *
+ * Convert link speed supported by HW to link speed supported by virtchnl.
+ * If adv_link_support is true, then return link speed in Mbps. Else return
+ * link speed as a VIRTCHNL_LINK_SPEED_* casted to a u32. Note that the caller
+ * needs to cast back to an enum virtchnl_link_speed in the case where
+ * adv_link_support is false, but when adv_link_support is true the caller can
+ * expect the speed in Mbps.
+ */
+u32 ice_conv_link_speed_to_virtchnl(bool adv_link_support, u16 link_speed)
+{
+	/* convert a BIT() value into an array index */
+	u32 index = fls(link_speed) - 1;
+
+	if (adv_link_support)
+		return ice_get_link_speed(index);
+	else if (index < ARRAY_SIZE(ice_legacy_aq_to_vc_speed))
+		/* Virtchnl speeds are not defined for every speed supported in
+		 * the hardware. To maintain compatibility with older AVF
+		 * drivers, while reporting the speed the new speed values are
+		 * resolved to the closest known virtchnl speeds
+		 */
+		return ice_legacy_aq_to_vc_speed[index];
+
+	return VIRTCHNL_LINK_SPEED_UNKNOWN;
+}
+
+/* The mailbox overflow detection algorithm helps to check if there
+ * is a possibility of a malicious VF transmitting too many MBX messages to the
+ * PF.
+ * 1. The mailbox snapshot structure, ice_mbx_snapshot, is initialized during
+ * driver initialization in ice_init_hw() using ice_mbx_init_snapshot().
+ * The struct ice_mbx_snapshot helps to track and traverse a static window of
+ * messages within the mailbox queue while looking for a malicious VF.
+ *
+ * 2. When the caller starts processing its mailbox queue in response to an
+ * interrupt, the structure ice_mbx_snapshot is expected to be cleared before
+ * the algorithm can be run for the first time for that interrupt. This
+ * requires calling ice_mbx_reset_snapshot() as well as calling
+ * ice_mbx_reset_vf_info() for each VF tracking structure.
+ *
+ * 3. For every message read by the caller from the MBX Queue, the caller must
+ * call the detection algorithm's entry function ice_mbx_vf_state_handler().
+ * Before every call to ice_mbx_vf_state_handler() the struct ice_mbx_data is
+ * filled as it is required to be passed to the algorithm.
+ *
+ * 4. Every time a message is read from the MBX queue, a tracking structure
+ * for the VF must be passed to the state handler. The boolean output
+ * report_malvf from ice_mbx_vf_state_handler() serves as an indicator to the
+ * caller whether it must report this VF as malicious or not.
+ *
+ * 5. When a VF is identified to be malicious, the caller can send a message
+ * to the system administrator.
+ *
+ * 6. The PF is responsible for maintaining the struct ice_mbx_vf_info
+ * structure for each VF. The PF should clear the VF tracking structure if the
+ * VF is reset. When a VF is shut down and brought back up, we will then
+ * assume that the new VF is not malicious and may report it again if we
+ * detect it again.
+ *
+ * 7. The function ice_mbx_reset_snapshot() is called to reset the information
+ * in ice_mbx_snapshot for every new mailbox interrupt handled.
+ */
+#define ICE_RQ_DATA_MASK(rq_data) ((rq_data) & PF_MBX_ARQH_ARQH_M)
+/* Using the highest value for an unsigned 16-bit value 0xFFFF to indicate that
+ * the max messages check must be ignored in the algorithm
+ */
+#define ICE_IGNORE_MAX_MSG_CNT	0xFFFF
+
+/**
+ * ice_mbx_reset_snapshot - Reset mailbox snapshot structure
+ * @snap: pointer to the mailbox snapshot
+ */
+static void ice_mbx_reset_snapshot(struct ice_mbx_snapshot *snap)
+{
+	struct ice_mbx_vf_info *vf_info;
+
+	/* Clear mbx_buf in the mailbox snaphot structure and setting the
+	 * mailbox snapshot state to a new capture.
+	 */
+	memset(&snap->mbx_buf, 0, sizeof(snap->mbx_buf));
+	snap->mbx_buf.state = ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT;
+
+	/* Reset message counts for all VFs to zero */
+	list_for_each_entry(vf_info, &snap->mbx_vf, list_entry)
+		vf_info->msg_count = 0;
+}
+
+/**
+ * ice_mbx_traverse - Pass through mailbox snapshot
+ * @hw: pointer to the HW struct
+ * @new_state: new algorithm state
+ *
+ * Traversing the mailbox static snapshot without checking
+ * for malicious VFs.
+ */
+static void
+ice_mbx_traverse(struct ice_hw *hw,
+		 enum ice_mbx_snapshot_state *new_state)
+{
+	struct ice_mbx_snap_buffer_data *snap_buf;
+	u32 num_iterations;
+
+	snap_buf = &hw->mbx_snapshot.mbx_buf;
+
+	/* As mailbox buffer is circular, applying a mask
+	 * on the incremented iteration count.
+	 */
+	num_iterations = ICE_RQ_DATA_MASK(++snap_buf->num_iterations);
+
+	/* Checking either of the below conditions to exit snapshot traversal:
+	 * Condition-1: If the number of iterations in the mailbox is equal to
+	 * the mailbox head which would indicate that we have reached the end
+	 * of the static snapshot.
+	 * Condition-2: If the maximum messages serviced in the mailbox for a
+	 * given interrupt is the highest possible value then there is no need
+	 * to check if the number of messages processed is equal to it. If not
+	 * check if the number of messages processed is greater than or equal
+	 * to the maximum number of mailbox entries serviced in current work item.
+	 */
+	if (num_iterations == snap_buf->head ||
+	    (snap_buf->max_num_msgs_mbx < ICE_IGNORE_MAX_MSG_CNT &&
+	     ++snap_buf->num_msg_proc >= snap_buf->max_num_msgs_mbx))
+		*new_state = ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT;
+}
+
+/**
+ * ice_mbx_detect_malvf - Detect malicious VF in snapshot
+ * @hw: pointer to the HW struct
+ * @vf_info: mailbox tracking structure for a VF
+ * @new_state: new algorithm state
+ * @is_malvf: boolean output to indicate if VF is malicious
+ *
+ * This function tracks the number of asynchronous messages
+ * sent per VF and marks the VF as malicious if it exceeds
+ * the permissible number of messages to send.
+ */
+static int
+ice_mbx_detect_malvf(struct ice_hw *hw, struct ice_mbx_vf_info *vf_info,
+		     enum ice_mbx_snapshot_state *new_state,
+		     bool *is_malvf)
+{
+	/* increment the message count for this VF */
+	vf_info->msg_count++;
+
+	if (vf_info->msg_count >= ICE_ASYNC_VF_MSG_THRESHOLD)
+		*is_malvf = true;
+
+	/* continue to iterate through the mailbox snapshot */
+	ice_mbx_traverse(hw, new_state);
+
+	return 0;
+}
+
+/**
+ * ice_mbx_vf_state_handler - Handle states of the overflow algorithm
+ * @hw: pointer to the HW struct
+ * @mbx_data: pointer to structure containing mailbox data
+ * @vf_info: mailbox tracking structure for the VF in question
+ * @report_malvf: boolean output to indicate whether VF should be reported
+ *
+ * The function serves as an entry point for the malicious VF
+ * detection algorithm by handling the different states and state
+ * transitions of the algorithm:
+ * New snapshot: This state is entered when creating a new static
+ * snapshot. The data from any previous mailbox snapshot is
+ * cleared and a new capture of the mailbox head and tail is
+ * logged. This will be the new static snapshot to detect
+ * asynchronous messages sent by VFs. On capturing the snapshot
+ * and depending on whether the number of pending messages in that
+ * snapshot exceed the watermark value, the state machine enters
+ * traverse or detect states.
+ * Traverse: If pending message count is below watermark then iterate
+ * through the snapshot without any action on VF.
+ * Detect: If pending message count exceeds watermark traverse
+ * the static snapshot and look for a malicious VF.
+ */
+int
+ice_mbx_vf_state_handler(struct ice_hw *hw, struct ice_mbx_data *mbx_data,
+			 struct ice_mbx_vf_info *vf_info, bool *report_malvf)
+{
+	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;
+	struct ice_mbx_snap_buffer_data *snap_buf;
+	struct ice_ctl_q_info *cq = &hw->mailboxq;
+	enum ice_mbx_snapshot_state new_state;
+	bool is_malvf = false;
+	int status = 0;
+
+	if (!report_malvf || !mbx_data || !vf_info)
+		return -EINVAL;
+
+	*report_malvf = false;
+
+	/* When entering the mailbox state machine assume that the VF
+	 * is not malicious until detected.
+	 */
+	 /* Checking if max messages allowed to be processed while servicing current
+	  * interrupt is not less than the defined AVF message threshold.
+	  */
+	if (mbx_data->max_num_msgs_mbx <= ICE_ASYNC_VF_MSG_THRESHOLD)
+		return -EINVAL;
+
+	/* The watermark value should not be lesser than the threshold limit
+	 * set for the number of asynchronous messages a VF can send to mailbox
+	 * nor should it be greater than the maximum number of messages in the
+	 * mailbox serviced in current interrupt.
+	 */
+	if (mbx_data->async_watermark_val < ICE_ASYNC_VF_MSG_THRESHOLD ||
+	    mbx_data->async_watermark_val > mbx_data->max_num_msgs_mbx)
+		return -EINVAL;
+
+	new_state = ICE_MAL_VF_DETECT_STATE_INVALID;
+	snap_buf = &snap->mbx_buf;
+
+	switch (snap_buf->state) {
+	case ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT:
+		/* Clear any previously held data in mailbox snapshot structure. */
+		ice_mbx_reset_snapshot(snap);
+
+		/* Collect the pending ARQ count, number of messages processed and
+		 * the maximum number of messages allowed to be processed from the
+		 * Mailbox for current interrupt.
+		 */
+		snap_buf->num_pending_arq = mbx_data->num_pending_arq;
+		snap_buf->num_msg_proc = mbx_data->num_msg_proc;
+		snap_buf->max_num_msgs_mbx = mbx_data->max_num_msgs_mbx;
+
+		/* Capture a new static snapshot of the mailbox by logging the
+		 * head and tail of snapshot and set num_iterations to the tail
+		 * value to mark the start of the iteration through the snapshot.
+		 */
+		snap_buf->head = ICE_RQ_DATA_MASK(cq->rq.next_to_clean +
+						  mbx_data->num_pending_arq);
+		snap_buf->tail = ICE_RQ_DATA_MASK(cq->rq.next_to_clean - 1);
+		snap_buf->num_iterations = snap_buf->tail;
+
+		/* Pending ARQ messages returned by ice_clean_rq_elem
+		 * is the difference between the head and tail of the
+		 * mailbox queue. Comparing this value against the watermark
+		 * helps to check if we potentially have malicious VFs.
+		 */
+		if (snap_buf->num_pending_arq >=
+		    mbx_data->async_watermark_val) {
+			new_state = ICE_MAL_VF_DETECT_STATE_DETECT;
+			status = ice_mbx_detect_malvf(hw, vf_info, &new_state, &is_malvf);
+		} else {
+			new_state = ICE_MAL_VF_DETECT_STATE_TRAVERSE;
+			ice_mbx_traverse(hw, &new_state);
+		}
+		break;
+
+	case ICE_MAL_VF_DETECT_STATE_TRAVERSE:
+		new_state = ICE_MAL_VF_DETECT_STATE_TRAVERSE;
+		ice_mbx_traverse(hw, &new_state);
+		break;
+
+	case ICE_MAL_VF_DETECT_STATE_DETECT:
+		new_state = ICE_MAL_VF_DETECT_STATE_DETECT;
+		status = ice_mbx_detect_malvf(hw, vf_info, &new_state, &is_malvf);
+		break;
+
+	default:
+		new_state = ICE_MAL_VF_DETECT_STATE_INVALID;
+		status = -EIO;
+	}
+
+	snap_buf->state = new_state;
+
+	/* Only report VFs as malicious the first time we detect it */
+	if (is_malvf && !vf_info->malicious) {
+		vf_info->malicious = 1;
+		*report_malvf = true;
+	}
+
+	return status;
+}
+
+/**
+ * ice_mbx_clear_malvf - Clear VF mailbox info
+ * @vf_info: the mailbox tracking structure for a VF
+ *
+ * In case of a VF reset, this function shall be called to clear the VF's
+ * current mailbox tracking state.
+ */
+void ice_mbx_clear_malvf(struct ice_mbx_vf_info *vf_info)
+{
+	vf_info->malicious = 0;
+	vf_info->msg_count = 0;
+}
+
+/**
+ * ice_mbx_init_vf_info - Initialize a new VF mailbox tracking info
+ * @hw: pointer to the hardware structure
+ * @vf_info: the mailbox tracking info structure for a VF
+ *
+ * Initialize a VF mailbox tracking info structure and insert it into the
+ * snapshot list.
+ *
+ * If you remove the VF, you must also delete the associated VF info structure
+ * from the linked list.
+ */
+void ice_mbx_init_vf_info(struct ice_hw *hw, struct ice_mbx_vf_info *vf_info)
+{
+	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;
+
+	ice_mbx_clear_malvf(vf_info);
+	list_add(&vf_info->list_entry, &snap->mbx_vf);
+}
+
+/**
+ * ice_mbx_init_snapshot - Initialize mailbox snapshot data
+ * @hw: pointer to the hardware structure
+ *
+ * Clear the mailbox snapshot structure and initialize the VF mailbox list.
+ */
+void ice_mbx_init_snapshot(struct ice_hw *hw)
+{
+	struct ice_mbx_snapshot *snap = &hw->mbx_snapshot;
+
+	INIT_LIST_HEAD(&snap->mbx_vf);
+	ice_mbx_reset_snapshot(snap);
+}