linux-zen-server/drivers/net/ethernet/intel/ice/ice_vf_mbx.c

484 lines
17 KiB
C

// 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));
}