// 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 can be * done via ice_mbx_reset_snapshot(). * * 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 VFId is received which * is passed to the state handler. The boolean output is_malvf of the state * handler ice_mbx_vf_state_handler() serves as an indicator to the caller * whether this VF is malicious or not. * * 5. When a VF is identified to be malicious, the caller can send a message * to the system administrator. The caller can invoke ice_mbx_report_malvf() * to help determine if a malicious VF is to be reported or not. This function * requires the caller to maintain a global bitmap to track all malicious VFs * and pass that to ice_mbx_report_malvf() along with the VFID which was identified * to be malicious by ice_mbx_vf_state_handler(). * * 6. The global bitmap maintained by PF can be cleared completely if PF is in * reset or the bit corresponding to a VF can be cleared if that VF is in reset. * When a VF is shut down and brought back up, we assume that the new VF * brought up is not malicious and hence report it if found malicious. * * 7. The function ice_mbx_reset_snapshot() is called to reset the information * in ice_mbx_snapshot for every new mailbox interrupt handled. * * 8. The memory allocated for variables in ice_mbx_snapshot is de-allocated * when driver is unloaded. */ #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_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_id: relative virtual function ID * @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, u16 vf_id, enum ice_mbx_snapshot_state *new_state, bool *is_malvf) { struct ice_mbx_snapshot *snap = &hw->mbx_snapshot; if (vf_id >= snap->mbx_vf.vfcntr_len) return -EIO; /* increment the message count in the VF array */ snap->mbx_vf.vf_cntr[vf_id]++; if (snap->mbx_vf.vf_cntr[vf_id] >= 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_reset_snapshot - Reset mailbox snapshot structure * @snap: pointer to mailbox snapshot structure in the ice_hw struct * * Reset the mailbox snapshot structure and clear VF counter array. */ static void ice_mbx_reset_snapshot(struct ice_mbx_snapshot *snap) { u32 vfcntr_len; if (!snap || !snap->mbx_vf.vf_cntr) return; /* Clear VF counters. */ vfcntr_len = snap->mbx_vf.vfcntr_len; if (vfcntr_len) memset(snap->mbx_vf.vf_cntr, 0, (vfcntr_len * sizeof(*snap->mbx_vf.vf_cntr))); /* Reset mailbox snapshot for a new capture. */ memset(&snap->mbx_buf, 0, sizeof(snap->mbx_buf)); snap->mbx_buf.state = ICE_MAL_VF_DETECT_STATE_NEW_SNAPSHOT; } /** * 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_id: relative virtual function (VF) ID * @is_malvf: boolean output to indicate if VF is malicious * * 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, u16 vf_id, bool *is_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; int status = 0; if (!is_malvf || !mbx_data) return -EINVAL; /* When entering the mailbox state machine assume that the VF * is not malicious until detected. */ *is_malvf = false; /* 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_id, &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_id, &new_state, is_malvf); break; default: new_state = ICE_MAL_VF_DETECT_STATE_INVALID; status = -EIO; } snap_buf->state = new_state; return status; } /** * ice_mbx_report_malvf - Track and note malicious VF * @hw: pointer to the HW struct * @all_malvfs: all malicious VFs tracked by PF * @bitmap_len: length of bitmap in bits * @vf_id: relative virtual function ID of the malicious VF * @report_malvf: boolean to indicate if malicious VF must be reported * * This function will update a bitmap that keeps track of the malicious * VFs attached to the PF. A malicious VF must be reported only once if * discovered between VF resets or loading so the function checks * the input vf_id against the bitmap to verify if the VF has been * detected in any previous mailbox iterations. */ int ice_mbx_report_malvf(struct ice_hw *hw, unsigned long *all_malvfs, u16 bitmap_len, u16 vf_id, bool *report_malvf) { if (!all_malvfs || !report_malvf) return -EINVAL; *report_malvf = false; if (bitmap_len < hw->mbx_snapshot.mbx_vf.vfcntr_len) return -EINVAL; if (vf_id >= bitmap_len) return -EIO; /* If the vf_id is found in the bitmap set bit and boolean to true */ if (!test_and_set_bit(vf_id, all_malvfs)) *report_malvf = true; return 0; } /** * ice_mbx_clear_malvf - Clear VF bitmap and counter for VF ID * @snap: pointer to the mailbox snapshot structure * @all_malvfs: all malicious VFs tracked by PF * @bitmap_len: length of bitmap in bits * @vf_id: relative virtual function ID of the malicious VF * * In case of a VF reset, this function can be called to clear * the bit corresponding to the VF ID in the bitmap tracking all * malicious VFs attached to the PF. The function also clears the * VF counter array at the index of the VF ID. This is to ensure * that the new VF loaded is not considered malicious before going * through the overflow detection algorithm. */ int ice_mbx_clear_malvf(struct ice_mbx_snapshot *snap, unsigned long *all_malvfs, u16 bitmap_len, u16 vf_id) { if (!snap || !all_malvfs) return -EINVAL; if (bitmap_len < snap->mbx_vf.vfcntr_len) return -EINVAL; /* Ensure VF ID value is not larger than bitmap or VF counter length */ if (vf_id >= bitmap_len || vf_id >= snap->mbx_vf.vfcntr_len) return -EIO; /* Clear VF ID bit in the bitmap tracking malicious VFs attached to PF */ clear_bit(vf_id, all_malvfs); /* Clear the VF counter in the mailbox snapshot structure for that VF ID. * This is to ensure that if a VF is unloaded and a new one brought back * up with the same VF ID for a snapshot currently in traversal or detect * state the counter for that VF ID does not increment on top of existing * values in the mailbox overflow detection algorithm. */ snap->mbx_vf.vf_cntr[vf_id] = 0; return 0; } /** * ice_mbx_init_snapshot - Initialize mailbox snapshot structure * @hw: pointer to the hardware structure * @vf_count: number of VFs allocated on a PF * * Clear the mailbox snapshot structure and allocate memory * for the VF counter array based on the number of VFs allocated * on that PF. * * Assumption: This function will assume ice_get_caps() has already been * called to ensure that the vf_count can be compared against the number * of VFs supported as defined in the functional capabilities of the device. */ int ice_mbx_init_snapshot(struct ice_hw *hw, u16 vf_count) { struct ice_mbx_snapshot *snap = &hw->mbx_snapshot; /* Ensure that the number of VFs allocated is non-zero and * is not greater than the number of supported VFs defined in * the functional capabilities of the PF. */ if (!vf_count || vf_count > hw->func_caps.num_allocd_vfs) return -EINVAL; snap->mbx_vf.vf_cntr = devm_kcalloc(ice_hw_to_dev(hw), vf_count, sizeof(*snap->mbx_vf.vf_cntr), GFP_KERNEL); if (!snap->mbx_vf.vf_cntr) return -ENOMEM; /* Setting the VF counter length to the number of allocated * VFs for given PF's functional capabilities. */ snap->mbx_vf.vfcntr_len = vf_count; /* 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; return 0; } /** * ice_mbx_deinit_snapshot - Free mailbox snapshot structure * @hw: pointer to the hardware structure * * Clear the mailbox snapshot structure and free the VF counter array. */ void ice_mbx_deinit_snapshot(struct ice_hw *hw) { struct ice_mbx_snapshot *snap = &hw->mbx_snapshot; /* Free VF counter array and reset VF counter length */ devm_kfree(ice_hw_to_dev(hw), snap->mbx_vf.vf_cntr); snap->mbx_vf.vfcntr_len = 0; /* Clear mbx_buf in the mailbox snaphot structure */ memset(&snap->mbx_buf, 0, sizeof(snap->mbx_buf)); }