summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/intel/ice/ice_vf_mbx.c
blob: fc8c93fa4455e1fbb50b3bf2cb4c840b1b24ea20 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
// 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);
}

/**
 * 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)
{
	u32 speed;

	if (adv_link_support)
		switch (link_speed) {
		case ICE_AQ_LINK_SPEED_10MB:
			speed = ICE_LINK_SPEED_10MBPS;
			break;
		case ICE_AQ_LINK_SPEED_100MB:
			speed = ICE_LINK_SPEED_100MBPS;
			break;
		case ICE_AQ_LINK_SPEED_1000MB:
			speed = ICE_LINK_SPEED_1000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_2500MB:
			speed = ICE_LINK_SPEED_2500MBPS;
			break;
		case ICE_AQ_LINK_SPEED_5GB:
			speed = ICE_LINK_SPEED_5000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_10GB:
			speed = ICE_LINK_SPEED_10000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_20GB:
			speed = ICE_LINK_SPEED_20000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_25GB:
			speed = ICE_LINK_SPEED_25000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_40GB:
			speed = ICE_LINK_SPEED_40000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_50GB:
			speed = ICE_LINK_SPEED_50000MBPS;
			break;
		case ICE_AQ_LINK_SPEED_100GB:
			speed = ICE_LINK_SPEED_100000MBPS;
			break;
		default:
			speed = ICE_LINK_SPEED_UNKNOWN;
			break;
		}
	else
		/* 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
		 */
		switch (link_speed) {
		case ICE_AQ_LINK_SPEED_10MB:
		case ICE_AQ_LINK_SPEED_100MB:
			speed = (u32)VIRTCHNL_LINK_SPEED_100MB;
			break;
		case ICE_AQ_LINK_SPEED_1000MB:
		case ICE_AQ_LINK_SPEED_2500MB:
		case ICE_AQ_LINK_SPEED_5GB:
			speed = (u32)VIRTCHNL_LINK_SPEED_1GB;
			break;
		case ICE_AQ_LINK_SPEED_10GB:
			speed = (u32)VIRTCHNL_LINK_SPEED_10GB;
			break;
		case ICE_AQ_LINK_SPEED_20GB:
			speed = (u32)VIRTCHNL_LINK_SPEED_20GB;
			break;
		case ICE_AQ_LINK_SPEED_25GB:
			speed = (u32)VIRTCHNL_LINK_SPEED_25GB;
			break;
		case ICE_AQ_LINK_SPEED_40GB:
		case ICE_AQ_LINK_SPEED_50GB:
		case ICE_AQ_LINK_SPEED_100GB:
			speed = (u32)VIRTCHNL_LINK_SPEED_40GB;
			break;
		default:
			speed = (u32)VIRTCHNL_LINK_SPEED_UNKNOWN;
			break;
		}

	return speed;
}

/* 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));
}