xref: /linux/drivers/gpu/drm/i915/i915_cmd_parser.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
1 /*
2  * Copyright © 2013 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Brad Volkin <bradley.d.volkin@intel.com>
25  *
26  */
27 
28 #include "i915_drv.h"
29 
30 /**
31  * DOC: batch buffer command parser
32  *
33  * Motivation:
34  * Certain OpenGL features (e.g. transform feedback, performance monitoring)
35  * require userspace code to submit batches containing commands such as
36  * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
37  * generations of the hardware will noop these commands in "unsecure" batches
38  * (which includes all userspace batches submitted via i915) even though the
39  * commands may be safe and represent the intended programming model of the
40  * device.
41  *
42  * The software command parser is similar in operation to the command parsing
43  * done in hardware for unsecure batches. However, the software parser allows
44  * some operations that would be noop'd by hardware, if the parser determines
45  * the operation is safe, and submits the batch as "secure" to prevent hardware
46  * parsing.
47  *
48  * Threats:
49  * At a high level, the hardware (and software) checks attempt to prevent
50  * granting userspace undue privileges. There are three categories of privilege.
51  *
52  * First, commands which are explicitly defined as privileged or which should
53  * only be used by the kernel driver. The parser generally rejects such
54  * commands, though it may allow some from the drm master process.
55  *
56  * Second, commands which access registers. To support correct/enhanced
57  * userspace functionality, particularly certain OpenGL extensions, the parser
58  * provides a whitelist of registers which userspace may safely access (for both
59  * normal and drm master processes).
60  *
61  * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc).
62  * The parser always rejects such commands.
63  *
64  * The majority of the problematic commands fall in the MI_* range, with only a
65  * few specific commands on each ring (e.g. PIPE_CONTROL and MI_FLUSH_DW).
66  *
67  * Implementation:
68  * Each ring maintains tables of commands and registers which the parser uses in
69  * scanning batch buffers submitted to that ring.
70  *
71  * Since the set of commands that the parser must check for is significantly
72  * smaller than the number of commands supported, the parser tables contain only
73  * those commands required by the parser. This generally works because command
74  * opcode ranges have standard command length encodings. So for commands that
75  * the parser does not need to check, it can easily skip them. This is
76  * implemented via a per-ring length decoding vfunc.
77  *
78  * Unfortunately, there are a number of commands that do not follow the standard
79  * length encoding for their opcode range, primarily amongst the MI_* commands.
80  * To handle this, the parser provides a way to define explicit "skip" entries
81  * in the per-ring command tables.
82  *
83  * Other command table entries map fairly directly to high level categories
84  * mentioned above: rejected, master-only, register whitelist. The parser
85  * implements a number of checks, including the privileged memory checks, via a
86  * general bitmasking mechanism.
87  */
88 
89 #define STD_MI_OPCODE_MASK  0xFF800000
90 #define STD_3D_OPCODE_MASK  0xFFFF0000
91 #define STD_2D_OPCODE_MASK  0xFFC00000
92 #define STD_MFX_OPCODE_MASK 0xFFFF0000
93 
94 #define CMD(op, opm, f, lm, fl, ...)				\
95 	{							\
96 		.flags = (fl) | ((f) ? CMD_DESC_FIXED : 0),	\
97 		.cmd = { (op), (opm) }, 			\
98 		.length = { (lm) },				\
99 		__VA_ARGS__					\
100 	}
101 
102 /* Convenience macros to compress the tables */
103 #define SMI STD_MI_OPCODE_MASK
104 #define S3D STD_3D_OPCODE_MASK
105 #define S2D STD_2D_OPCODE_MASK
106 #define SMFX STD_MFX_OPCODE_MASK
107 #define F true
108 #define S CMD_DESC_SKIP
109 #define R CMD_DESC_REJECT
110 #define W CMD_DESC_REGISTER
111 #define B CMD_DESC_BITMASK
112 #define M CMD_DESC_MASTER
113 
114 /*            Command                          Mask   Fixed Len   Action
115 	      ---------------------------------------------------------- */
116 static const struct drm_i915_cmd_descriptor common_cmds[] = {
117 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
118 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      R  ),
119 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      M  ),
120 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
121 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
122 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
123 	CMD(  MI_SEMAPHORE_MBOX,                SMI,   !F,  0xFF,   R  ),
124 	CMD(  MI_STORE_DWORD_INDEX,             SMI,   !F,  0xFF,   R  ),
125 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
126 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
127 	CMD(  MI_STORE_REGISTER_MEM(1),         SMI,   !F,  0xFF,   W | B,
128 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
129 	      .bits = {{
130 			.offset = 0,
131 			.mask = MI_GLOBAL_GTT,
132 			.expected = 0,
133 	      }},						       ),
134 	CMD(  MI_LOAD_REGISTER_MEM,             SMI,   !F,  0xFF,   W | B,
135 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
136 	      .bits = {{
137 			.offset = 0,
138 			.mask = MI_GLOBAL_GTT,
139 			.expected = 0,
140 	      }},						       ),
141 	/*
142 	 * MI_BATCH_BUFFER_START requires some special handling. It's not
143 	 * really a 'skip' action but it doesn't seem like it's worth adding
144 	 * a new action. See i915_parse_cmds().
145 	 */
146 	CMD(  MI_BATCH_BUFFER_START,            SMI,   !F,  0xFF,   S  ),
147 };
148 
149 static const struct drm_i915_cmd_descriptor render_cmds[] = {
150 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
151 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
152 	CMD(  MI_PREDICATE,                     SMI,    F,  1,      S  ),
153 	CMD(  MI_TOPOLOGY_FILTER,               SMI,    F,  1,      S  ),
154 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
155 	CMD(  MI_SET_CONTEXT,                   SMI,   !F,  0xFF,   R  ),
156 	CMD(  MI_URB_CLEAR,                     SMI,   !F,  0xFF,   S  ),
157 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3F,   B,
158 	      .bits = {{
159 			.offset = 0,
160 			.mask = MI_GLOBAL_GTT,
161 			.expected = 0,
162 	      }},						       ),
163 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0xFF,   R  ),
164 	CMD(  MI_CLFLUSH,                       SMI,   !F,  0x3FF,  B,
165 	      .bits = {{
166 			.offset = 0,
167 			.mask = MI_GLOBAL_GTT,
168 			.expected = 0,
169 	      }},						       ),
170 	CMD(  MI_REPORT_PERF_COUNT,             SMI,   !F,  0x3F,   B,
171 	      .bits = {{
172 			.offset = 1,
173 			.mask = MI_REPORT_PERF_COUNT_GGTT,
174 			.expected = 0,
175 	      }},						       ),
176 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
177 	      .bits = {{
178 			.offset = 0,
179 			.mask = MI_GLOBAL_GTT,
180 			.expected = 0,
181 	      }},						       ),
182 	CMD(  GFX_OP_3DSTATE_VF_STATISTICS,     S3D,    F,  1,      S  ),
183 	CMD(  PIPELINE_SELECT,                  S3D,    F,  1,      S  ),
184 	CMD(  MEDIA_VFE_STATE,			S3D,   !F,  0xFFFF, B,
185 	      .bits = {{
186 			.offset = 2,
187 			.mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK,
188 			.expected = 0,
189 	      }},						       ),
190 	CMD(  GPGPU_OBJECT,                     S3D,   !F,  0xFF,   S  ),
191 	CMD(  GPGPU_WALKER,                     S3D,   !F,  0xFF,   S  ),
192 	CMD(  GFX_OP_3DSTATE_SO_DECL_LIST,      S3D,   !F,  0x1FF,  S  ),
193 	CMD(  GFX_OP_PIPE_CONTROL(5),           S3D,   !F,  0xFF,   B,
194 	      .bits = {{
195 			.offset = 1,
196 			.mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY),
197 			.expected = 0,
198 	      },
199 	      {
200 			.offset = 1,
201 		        .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
202 				 PIPE_CONTROL_STORE_DATA_INDEX),
203 			.expected = 0,
204 			.condition_offset = 1,
205 			.condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
206 	      }},						       ),
207 };
208 
209 static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = {
210 	CMD(  MI_SET_PREDICATE,                 SMI,    F,  1,      S  ),
211 	CMD(  MI_RS_CONTROL,                    SMI,    F,  1,      S  ),
212 	CMD(  MI_URB_ATOMIC_ALLOC,              SMI,    F,  1,      S  ),
213 	CMD(  MI_RS_CONTEXT,                    SMI,    F,  1,      S  ),
214 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   M  ),
215 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
216 	CMD(  MI_LOAD_REGISTER_REG,             SMI,   !F,  0xFF,   R  ),
217 	CMD(  MI_RS_STORE_DATA_IMM,             SMI,   !F,  0xFF,   S  ),
218 	CMD(  MI_LOAD_URB_MEM,                  SMI,   !F,  0xFF,   S  ),
219 	CMD(  MI_STORE_URB_MEM,                 SMI,   !F,  0xFF,   S  ),
220 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_VS,  S3D,   !F,  0x7FF,  S  ),
221 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_PS,  S3D,   !F,  0x7FF,  S  ),
222 
223 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS,  S3D,   !F,  0x1FF,  S  ),
224 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS,  S3D,   !F,  0x1FF,  S  ),
225 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS,  S3D,   !F,  0x1FF,  S  ),
226 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS,  S3D,   !F,  0x1FF,  S  ),
227 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS,  S3D,   !F,  0x1FF,  S  ),
228 };
229 
230 static const struct drm_i915_cmd_descriptor video_cmds[] = {
231 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
232 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
233 	      .bits = {{
234 			.offset = 0,
235 			.mask = MI_GLOBAL_GTT,
236 			.expected = 0,
237 	      }},						       ),
238 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
239 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
240 	      .bits = {{
241 			.offset = 0,
242 			.mask = MI_FLUSH_DW_NOTIFY,
243 			.expected = 0,
244 	      },
245 	      {
246 			.offset = 1,
247 			.mask = MI_FLUSH_DW_USE_GTT,
248 			.expected = 0,
249 			.condition_offset = 0,
250 			.condition_mask = MI_FLUSH_DW_OP_MASK,
251 	      },
252 	      {
253 			.offset = 0,
254 			.mask = MI_FLUSH_DW_STORE_INDEX,
255 			.expected = 0,
256 			.condition_offset = 0,
257 			.condition_mask = MI_FLUSH_DW_OP_MASK,
258 	      }},						       ),
259 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
260 	      .bits = {{
261 			.offset = 0,
262 			.mask = MI_GLOBAL_GTT,
263 			.expected = 0,
264 	      }},						       ),
265 	/*
266 	 * MFX_WAIT doesn't fit the way we handle length for most commands.
267 	 * It has a length field but it uses a non-standard length bias.
268 	 * It is always 1 dword though, so just treat it as fixed length.
269 	 */
270 	CMD(  MFX_WAIT,                         SMFX,   F,  1,      S  ),
271 };
272 
273 static const struct drm_i915_cmd_descriptor vecs_cmds[] = {
274 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
275 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
276 	      .bits = {{
277 			.offset = 0,
278 			.mask = MI_GLOBAL_GTT,
279 			.expected = 0,
280 	      }},						       ),
281 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
282 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
283 	      .bits = {{
284 			.offset = 0,
285 			.mask = MI_FLUSH_DW_NOTIFY,
286 			.expected = 0,
287 	      },
288 	      {
289 			.offset = 1,
290 			.mask = MI_FLUSH_DW_USE_GTT,
291 			.expected = 0,
292 			.condition_offset = 0,
293 			.condition_mask = MI_FLUSH_DW_OP_MASK,
294 	      },
295 	      {
296 			.offset = 0,
297 			.mask = MI_FLUSH_DW_STORE_INDEX,
298 			.expected = 0,
299 			.condition_offset = 0,
300 			.condition_mask = MI_FLUSH_DW_OP_MASK,
301 	      }},						       ),
302 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
303 	      .bits = {{
304 			.offset = 0,
305 			.mask = MI_GLOBAL_GTT,
306 			.expected = 0,
307 	      }},						       ),
308 };
309 
310 static const struct drm_i915_cmd_descriptor blt_cmds[] = {
311 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
312 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  B,
313 	      .bits = {{
314 			.offset = 0,
315 			.mask = MI_GLOBAL_GTT,
316 			.expected = 0,
317 	      }},						       ),
318 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
319 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
320 	      .bits = {{
321 			.offset = 0,
322 			.mask = MI_FLUSH_DW_NOTIFY,
323 			.expected = 0,
324 	      },
325 	      {
326 			.offset = 1,
327 			.mask = MI_FLUSH_DW_USE_GTT,
328 			.expected = 0,
329 			.condition_offset = 0,
330 			.condition_mask = MI_FLUSH_DW_OP_MASK,
331 	      },
332 	      {
333 			.offset = 0,
334 			.mask = MI_FLUSH_DW_STORE_INDEX,
335 			.expected = 0,
336 			.condition_offset = 0,
337 			.condition_mask = MI_FLUSH_DW_OP_MASK,
338 	      }},						       ),
339 	CMD(  COLOR_BLT,                        S2D,   !F,  0x3F,   S  ),
340 	CMD(  SRC_COPY_BLT,                     S2D,   !F,  0x3F,   S  ),
341 };
342 
343 static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = {
344 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   M  ),
345 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
346 };
347 
348 #undef CMD
349 #undef SMI
350 #undef S3D
351 #undef S2D
352 #undef SMFX
353 #undef F
354 #undef S
355 #undef R
356 #undef W
357 #undef B
358 #undef M
359 
360 static const struct drm_i915_cmd_table gen7_render_cmds[] = {
361 	{ common_cmds, ARRAY_SIZE(common_cmds) },
362 	{ render_cmds, ARRAY_SIZE(render_cmds) },
363 };
364 
365 static const struct drm_i915_cmd_table hsw_render_ring_cmds[] = {
366 	{ common_cmds, ARRAY_SIZE(common_cmds) },
367 	{ render_cmds, ARRAY_SIZE(render_cmds) },
368 	{ hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) },
369 };
370 
371 static const struct drm_i915_cmd_table gen7_video_cmds[] = {
372 	{ common_cmds, ARRAY_SIZE(common_cmds) },
373 	{ video_cmds, ARRAY_SIZE(video_cmds) },
374 };
375 
376 static const struct drm_i915_cmd_table hsw_vebox_cmds[] = {
377 	{ common_cmds, ARRAY_SIZE(common_cmds) },
378 	{ vecs_cmds, ARRAY_SIZE(vecs_cmds) },
379 };
380 
381 static const struct drm_i915_cmd_table gen7_blt_cmds[] = {
382 	{ common_cmds, ARRAY_SIZE(common_cmds) },
383 	{ blt_cmds, ARRAY_SIZE(blt_cmds) },
384 };
385 
386 static const struct drm_i915_cmd_table hsw_blt_ring_cmds[] = {
387 	{ common_cmds, ARRAY_SIZE(common_cmds) },
388 	{ blt_cmds, ARRAY_SIZE(blt_cmds) },
389 	{ hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) },
390 };
391 
392 /*
393  * Register whitelists, sorted by increasing register offset.
394  *
395  * Some registers that userspace accesses are 64 bits. The register
396  * access commands only allow 32-bit accesses. Hence, we have to include
397  * entries for both halves of the 64-bit registers.
398  */
399 
400 /* Convenience macro for adding 64-bit registers */
401 #define REG64(addr) (addr), (addr + sizeof(u32))
402 
403 static const u32 gen7_render_regs[] = {
404 	REG64(HS_INVOCATION_COUNT),
405 	REG64(DS_INVOCATION_COUNT),
406 	REG64(IA_VERTICES_COUNT),
407 	REG64(IA_PRIMITIVES_COUNT),
408 	REG64(VS_INVOCATION_COUNT),
409 	REG64(GS_INVOCATION_COUNT),
410 	REG64(GS_PRIMITIVES_COUNT),
411 	REG64(CL_INVOCATION_COUNT),
412 	REG64(CL_PRIMITIVES_COUNT),
413 	REG64(PS_INVOCATION_COUNT),
414 	REG64(PS_DEPTH_COUNT),
415 	OACONTROL, /* Only allowed for LRI and SRM. See below. */
416 	REG64(MI_PREDICATE_SRC0),
417 	REG64(MI_PREDICATE_SRC1),
418 	GEN7_3DPRIM_END_OFFSET,
419 	GEN7_3DPRIM_START_VERTEX,
420 	GEN7_3DPRIM_VERTEX_COUNT,
421 	GEN7_3DPRIM_INSTANCE_COUNT,
422 	GEN7_3DPRIM_START_INSTANCE,
423 	GEN7_3DPRIM_BASE_VERTEX,
424 	REG64(GEN7_SO_NUM_PRIMS_WRITTEN(0)),
425 	REG64(GEN7_SO_NUM_PRIMS_WRITTEN(1)),
426 	REG64(GEN7_SO_NUM_PRIMS_WRITTEN(2)),
427 	REG64(GEN7_SO_NUM_PRIMS_WRITTEN(3)),
428 	REG64(GEN7_SO_PRIM_STORAGE_NEEDED(0)),
429 	REG64(GEN7_SO_PRIM_STORAGE_NEEDED(1)),
430 	REG64(GEN7_SO_PRIM_STORAGE_NEEDED(2)),
431 	REG64(GEN7_SO_PRIM_STORAGE_NEEDED(3)),
432 	GEN7_SO_WRITE_OFFSET(0),
433 	GEN7_SO_WRITE_OFFSET(1),
434 	GEN7_SO_WRITE_OFFSET(2),
435 	GEN7_SO_WRITE_OFFSET(3),
436 	GEN7_L3SQCREG1,
437 	GEN7_L3CNTLREG2,
438 	GEN7_L3CNTLREG3,
439 };
440 
441 static const u32 gen7_blt_regs[] = {
442 	BCS_SWCTRL,
443 };
444 
445 static const u32 ivb_master_regs[] = {
446 	FORCEWAKE_MT,
447 	DERRMR,
448 	GEN7_PIPE_DE_LOAD_SL(PIPE_A),
449 	GEN7_PIPE_DE_LOAD_SL(PIPE_B),
450 	GEN7_PIPE_DE_LOAD_SL(PIPE_C),
451 };
452 
453 static const u32 hsw_master_regs[] = {
454 	FORCEWAKE_MT,
455 	DERRMR,
456 };
457 
458 #undef REG64
459 
460 static u32 gen7_render_get_cmd_length_mask(u32 cmd_header)
461 {
462 	u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
463 	u32 subclient =
464 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
465 
466 	if (client == INSTR_MI_CLIENT)
467 		return 0x3F;
468 	else if (client == INSTR_RC_CLIENT) {
469 		if (subclient == INSTR_MEDIA_SUBCLIENT)
470 			return 0xFFFF;
471 		else
472 			return 0xFF;
473 	}
474 
475 	DRM_DEBUG_DRIVER("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header);
476 	return 0;
477 }
478 
479 static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header)
480 {
481 	u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
482 	u32 subclient =
483 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
484 
485 	if (client == INSTR_MI_CLIENT)
486 		return 0x3F;
487 	else if (client == INSTR_RC_CLIENT) {
488 		if (subclient == INSTR_MEDIA_SUBCLIENT)
489 			return 0xFFF;
490 		else
491 			return 0xFF;
492 	}
493 
494 	DRM_DEBUG_DRIVER("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header);
495 	return 0;
496 }
497 
498 static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header)
499 {
500 	u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
501 
502 	if (client == INSTR_MI_CLIENT)
503 		return 0x3F;
504 	else if (client == INSTR_BC_CLIENT)
505 		return 0xFF;
506 
507 	DRM_DEBUG_DRIVER("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
508 	return 0;
509 }
510 
511 static bool validate_cmds_sorted(struct intel_engine_cs *ring,
512 				 const struct drm_i915_cmd_table *cmd_tables,
513 				 int cmd_table_count)
514 {
515 	int i;
516 	bool ret = true;
517 
518 	if (!cmd_tables || cmd_table_count == 0)
519 		return true;
520 
521 	for (i = 0; i < cmd_table_count; i++) {
522 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
523 		u32 previous = 0;
524 		int j;
525 
526 		for (j = 0; j < table->count; j++) {
527 			const struct drm_i915_cmd_descriptor *desc =
528 				&table->table[i];
529 			u32 curr = desc->cmd.value & desc->cmd.mask;
530 
531 			if (curr < previous) {
532 				DRM_ERROR("CMD: table not sorted ring=%d table=%d entry=%d cmd=0x%08X prev=0x%08X\n",
533 					  ring->id, i, j, curr, previous);
534 				ret = false;
535 			}
536 
537 			previous = curr;
538 		}
539 	}
540 
541 	return ret;
542 }
543 
544 static bool check_sorted(int ring_id, const u32 *reg_table, int reg_count)
545 {
546 	int i;
547 	u32 previous = 0;
548 	bool ret = true;
549 
550 	for (i = 0; i < reg_count; i++) {
551 		u32 curr = reg_table[i];
552 
553 		if (curr < previous) {
554 			DRM_ERROR("CMD: table not sorted ring=%d entry=%d reg=0x%08X prev=0x%08X\n",
555 				  ring_id, i, curr, previous);
556 			ret = false;
557 		}
558 
559 		previous = curr;
560 	}
561 
562 	return ret;
563 }
564 
565 static bool validate_regs_sorted(struct intel_engine_cs *ring)
566 {
567 	return check_sorted(ring->id, ring->reg_table, ring->reg_count) &&
568 		check_sorted(ring->id, ring->master_reg_table,
569 			     ring->master_reg_count);
570 }
571 
572 struct cmd_node {
573 	const struct drm_i915_cmd_descriptor *desc;
574 	struct hlist_node node;
575 };
576 
577 /*
578  * Different command ranges have different numbers of bits for the opcode. For
579  * example, MI commands use bits 31:23 while 3D commands use bits 31:16. The
580  * problem is that, for example, MI commands use bits 22:16 for other fields
581  * such as GGTT vs PPGTT bits. If we include those bits in the mask then when
582  * we mask a command from a batch it could hash to the wrong bucket due to
583  * non-opcode bits being set. But if we don't include those bits, some 3D
584  * commands may hash to the same bucket due to not including opcode bits that
585  * make the command unique. For now, we will risk hashing to the same bucket.
586  *
587  * If we attempt to generate a perfect hash, we should be able to look at bits
588  * 31:29 of a command from a batch buffer and use the full mask for that
589  * client. The existing INSTR_CLIENT_MASK/SHIFT defines can be used for this.
590  */
591 #define CMD_HASH_MASK STD_MI_OPCODE_MASK
592 
593 static int init_hash_table(struct intel_engine_cs *ring,
594 			   const struct drm_i915_cmd_table *cmd_tables,
595 			   int cmd_table_count)
596 {
597 	int i, j;
598 
599 	hash_init(ring->cmd_hash);
600 
601 	for (i = 0; i < cmd_table_count; i++) {
602 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
603 
604 		for (j = 0; j < table->count; j++) {
605 			const struct drm_i915_cmd_descriptor *desc =
606 				&table->table[j];
607 			struct cmd_node *desc_node =
608 				kmalloc(sizeof(*desc_node), GFP_KERNEL);
609 
610 			if (!desc_node)
611 				return -ENOMEM;
612 
613 			desc_node->desc = desc;
614 			hash_add(ring->cmd_hash, &desc_node->node,
615 				 desc->cmd.value & CMD_HASH_MASK);
616 		}
617 	}
618 
619 	return 0;
620 }
621 
622 static void fini_hash_table(struct intel_engine_cs *ring)
623 {
624 	struct hlist_node *tmp;
625 	struct cmd_node *desc_node;
626 	int i;
627 
628 	hash_for_each_safe(ring->cmd_hash, i, tmp, desc_node, node) {
629 		hash_del(&desc_node->node);
630 		kfree(desc_node);
631 	}
632 }
633 
634 /**
635  * i915_cmd_parser_init_ring() - set cmd parser related fields for a ringbuffer
636  * @ring: the ringbuffer to initialize
637  *
638  * Optionally initializes fields related to batch buffer command parsing in the
639  * struct intel_engine_cs based on whether the platform requires software
640  * command parsing.
641  *
642  * Return: non-zero if initialization fails
643  */
644 int i915_cmd_parser_init_ring(struct intel_engine_cs *ring)
645 {
646 	const struct drm_i915_cmd_table *cmd_tables;
647 	int cmd_table_count;
648 	int ret;
649 
650 	if (!IS_GEN7(ring->dev))
651 		return 0;
652 
653 	switch (ring->id) {
654 	case RCS:
655 		if (IS_HASWELL(ring->dev)) {
656 			cmd_tables = hsw_render_ring_cmds;
657 			cmd_table_count =
658 				ARRAY_SIZE(hsw_render_ring_cmds);
659 		} else {
660 			cmd_tables = gen7_render_cmds;
661 			cmd_table_count = ARRAY_SIZE(gen7_render_cmds);
662 		}
663 
664 		ring->reg_table = gen7_render_regs;
665 		ring->reg_count = ARRAY_SIZE(gen7_render_regs);
666 
667 		if (IS_HASWELL(ring->dev)) {
668 			ring->master_reg_table = hsw_master_regs;
669 			ring->master_reg_count = ARRAY_SIZE(hsw_master_regs);
670 		} else {
671 			ring->master_reg_table = ivb_master_regs;
672 			ring->master_reg_count = ARRAY_SIZE(ivb_master_regs);
673 		}
674 
675 		ring->get_cmd_length_mask = gen7_render_get_cmd_length_mask;
676 		break;
677 	case VCS:
678 		cmd_tables = gen7_video_cmds;
679 		cmd_table_count = ARRAY_SIZE(gen7_video_cmds);
680 		ring->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
681 		break;
682 	case BCS:
683 		if (IS_HASWELL(ring->dev)) {
684 			cmd_tables = hsw_blt_ring_cmds;
685 			cmd_table_count = ARRAY_SIZE(hsw_blt_ring_cmds);
686 		} else {
687 			cmd_tables = gen7_blt_cmds;
688 			cmd_table_count = ARRAY_SIZE(gen7_blt_cmds);
689 		}
690 
691 		ring->reg_table = gen7_blt_regs;
692 		ring->reg_count = ARRAY_SIZE(gen7_blt_regs);
693 
694 		if (IS_HASWELL(ring->dev)) {
695 			ring->master_reg_table = hsw_master_regs;
696 			ring->master_reg_count = ARRAY_SIZE(hsw_master_regs);
697 		} else {
698 			ring->master_reg_table = ivb_master_regs;
699 			ring->master_reg_count = ARRAY_SIZE(ivb_master_regs);
700 		}
701 
702 		ring->get_cmd_length_mask = gen7_blt_get_cmd_length_mask;
703 		break;
704 	case VECS:
705 		cmd_tables = hsw_vebox_cmds;
706 		cmd_table_count = ARRAY_SIZE(hsw_vebox_cmds);
707 		/* VECS can use the same length_mask function as VCS */
708 		ring->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
709 		break;
710 	default:
711 		DRM_ERROR("CMD: cmd_parser_init with unknown ring: %d\n",
712 			  ring->id);
713 		BUG();
714 	}
715 
716 	BUG_ON(!validate_cmds_sorted(ring, cmd_tables, cmd_table_count));
717 	BUG_ON(!validate_regs_sorted(ring));
718 
719 	if (hash_empty(ring->cmd_hash)) {
720 		ret = init_hash_table(ring, cmd_tables, cmd_table_count);
721 		if (ret) {
722 			DRM_ERROR("CMD: cmd_parser_init failed!\n");
723 			fini_hash_table(ring);
724 			return ret;
725 		}
726 	}
727 
728 	ring->needs_cmd_parser = true;
729 
730 	return 0;
731 }
732 
733 /**
734  * i915_cmd_parser_fini_ring() - clean up cmd parser related fields
735  * @ring: the ringbuffer to clean up
736  *
737  * Releases any resources related to command parsing that may have been
738  * initialized for the specified ring.
739  */
740 void i915_cmd_parser_fini_ring(struct intel_engine_cs *ring)
741 {
742 	if (!ring->needs_cmd_parser)
743 		return;
744 
745 	fini_hash_table(ring);
746 }
747 
748 static const struct drm_i915_cmd_descriptor*
749 find_cmd_in_table(struct intel_engine_cs *ring,
750 		  u32 cmd_header)
751 {
752 	struct cmd_node *desc_node;
753 
754 	hash_for_each_possible(ring->cmd_hash, desc_node, node,
755 			       cmd_header & CMD_HASH_MASK) {
756 		const struct drm_i915_cmd_descriptor *desc = desc_node->desc;
757 		u32 masked_cmd = desc->cmd.mask & cmd_header;
758 		u32 masked_value = desc->cmd.value & desc->cmd.mask;
759 
760 		if (masked_cmd == masked_value)
761 			return desc;
762 	}
763 
764 	return NULL;
765 }
766 
767 /*
768  * Returns a pointer to a descriptor for the command specified by cmd_header.
769  *
770  * The caller must supply space for a default descriptor via the default_desc
771  * parameter. If no descriptor for the specified command exists in the ring's
772  * command parser tables, this function fills in default_desc based on the
773  * ring's default length encoding and returns default_desc.
774  */
775 static const struct drm_i915_cmd_descriptor*
776 find_cmd(struct intel_engine_cs *ring,
777 	 u32 cmd_header,
778 	 struct drm_i915_cmd_descriptor *default_desc)
779 {
780 	const struct drm_i915_cmd_descriptor *desc;
781 	u32 mask;
782 
783 	desc = find_cmd_in_table(ring, cmd_header);
784 	if (desc)
785 		return desc;
786 
787 	mask = ring->get_cmd_length_mask(cmd_header);
788 	if (!mask)
789 		return NULL;
790 
791 	BUG_ON(!default_desc);
792 	default_desc->flags = CMD_DESC_SKIP;
793 	default_desc->length.mask = mask;
794 
795 	return default_desc;
796 }
797 
798 static bool valid_reg(const u32 *table, int count, u32 addr)
799 {
800 	if (table && count != 0) {
801 		int i;
802 
803 		for (i = 0; i < count; i++) {
804 			if (table[i] == addr)
805 				return true;
806 		}
807 	}
808 
809 	return false;
810 }
811 
812 static u32 *vmap_batch(struct drm_i915_gem_object *obj)
813 {
814 	int i;
815 	void *addr = NULL;
816 	struct sg_page_iter sg_iter;
817 	struct page **pages;
818 
819 	pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
820 	if (pages == NULL) {
821 		DRM_DEBUG_DRIVER("Failed to get space for pages\n");
822 		goto finish;
823 	}
824 
825 	i = 0;
826 	for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
827 		pages[i] = sg_page_iter_page(&sg_iter);
828 		i++;
829 	}
830 
831 	addr = vmap(pages, i, 0, PAGE_KERNEL);
832 	if (addr == NULL) {
833 		DRM_DEBUG_DRIVER("Failed to vmap pages\n");
834 		goto finish;
835 	}
836 
837 finish:
838 	if (pages)
839 		drm_free_large(pages);
840 	return (u32*)addr;
841 }
842 
843 /**
844  * i915_needs_cmd_parser() - should a given ring use software command parsing?
845  * @ring: the ring in question
846  *
847  * Only certain platforms require software batch buffer command parsing, and
848  * only when enabled via module parameter.
849  *
850  * Return: true if the ring requires software command parsing
851  */
852 bool i915_needs_cmd_parser(struct intel_engine_cs *ring)
853 {
854 	if (!ring->needs_cmd_parser)
855 		return false;
856 
857 	if (!USES_PPGTT(ring->dev))
858 		return false;
859 
860 	return (i915.enable_cmd_parser == 1);
861 }
862 
863 static bool check_cmd(const struct intel_engine_cs *ring,
864 		      const struct drm_i915_cmd_descriptor *desc,
865 		      const u32 *cmd,
866 		      const bool is_master,
867 		      bool *oacontrol_set)
868 {
869 	if (desc->flags & CMD_DESC_REJECT) {
870 		DRM_DEBUG_DRIVER("CMD: Rejected command: 0x%08X\n", *cmd);
871 		return false;
872 	}
873 
874 	if ((desc->flags & CMD_DESC_MASTER) && !is_master) {
875 		DRM_DEBUG_DRIVER("CMD: Rejected master-only command: 0x%08X\n",
876 				 *cmd);
877 		return false;
878 	}
879 
880 	if (desc->flags & CMD_DESC_REGISTER) {
881 		u32 reg_addr = cmd[desc->reg.offset] & desc->reg.mask;
882 
883 		/*
884 		 * OACONTROL requires some special handling for writes. We
885 		 * want to make sure that any batch which enables OA also
886 		 * disables it before the end of the batch. The goal is to
887 		 * prevent one process from snooping on the perf data from
888 		 * another process. To do that, we need to check the value
889 		 * that will be written to the register. Hence, limit
890 		 * OACONTROL writes to only MI_LOAD_REGISTER_IMM commands.
891 		 */
892 		if (reg_addr == OACONTROL) {
893 			if (desc->cmd.value == MI_LOAD_REGISTER_MEM) {
894 				DRM_DEBUG_DRIVER("CMD: Rejected LRM to OACONTROL\n");
895 				return false;
896 			}
897 
898 			if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1))
899 				*oacontrol_set = (cmd[2] != 0);
900 		}
901 
902 		if (!valid_reg(ring->reg_table,
903 			       ring->reg_count, reg_addr)) {
904 			if (!is_master ||
905 			    !valid_reg(ring->master_reg_table,
906 				       ring->master_reg_count,
907 				       reg_addr)) {
908 				DRM_DEBUG_DRIVER("CMD: Rejected register 0x%08X in command: 0x%08X (ring=%d)\n",
909 						 reg_addr,
910 						 *cmd,
911 						 ring->id);
912 				return false;
913 			}
914 		}
915 	}
916 
917 	if (desc->flags & CMD_DESC_BITMASK) {
918 		int i;
919 
920 		for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) {
921 			u32 dword;
922 
923 			if (desc->bits[i].mask == 0)
924 				break;
925 
926 			if (desc->bits[i].condition_mask != 0) {
927 				u32 offset =
928 					desc->bits[i].condition_offset;
929 				u32 condition = cmd[offset] &
930 					desc->bits[i].condition_mask;
931 
932 				if (condition == 0)
933 					continue;
934 			}
935 
936 			dword = cmd[desc->bits[i].offset] &
937 				desc->bits[i].mask;
938 
939 			if (dword != desc->bits[i].expected) {
940 				DRM_DEBUG_DRIVER("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (ring=%d)\n",
941 						 *cmd,
942 						 desc->bits[i].mask,
943 						 desc->bits[i].expected,
944 						 dword, ring->id);
945 				return false;
946 			}
947 		}
948 	}
949 
950 	return true;
951 }
952 
953 #define LENGTH_BIAS 2
954 
955 /**
956  * i915_parse_cmds() - parse a submitted batch buffer for privilege violations
957  * @ring: the ring on which the batch is to execute
958  * @batch_obj: the batch buffer in question
959  * @batch_start_offset: byte offset in the batch at which execution starts
960  * @is_master: is the submitting process the drm master?
961  *
962  * Parses the specified batch buffer looking for privilege violations as
963  * described in the overview.
964  *
965  * Return: non-zero if the parser finds violations or otherwise fails; -EACCES
966  * if the batch appears legal but should use hardware parsing
967  */
968 int i915_parse_cmds(struct intel_engine_cs *ring,
969 		    struct drm_i915_gem_object *batch_obj,
970 		    u32 batch_start_offset,
971 		    bool is_master)
972 {
973 	int ret = 0;
974 	u32 *cmd, *batch_base, *batch_end;
975 	struct drm_i915_cmd_descriptor default_desc = { 0 };
976 	int needs_clflush = 0;
977 	bool oacontrol_set = false; /* OACONTROL tracking. See check_cmd() */
978 
979 	ret = i915_gem_obj_prepare_shmem_read(batch_obj, &needs_clflush);
980 	if (ret) {
981 		DRM_DEBUG_DRIVER("CMD: failed to prep read\n");
982 		return ret;
983 	}
984 
985 	batch_base = vmap_batch(batch_obj);
986 	if (!batch_base) {
987 		DRM_DEBUG_DRIVER("CMD: Failed to vmap batch\n");
988 		i915_gem_object_unpin_pages(batch_obj);
989 		return -ENOMEM;
990 	}
991 
992 	if (needs_clflush)
993 		drm_clflush_virt_range((char *)batch_base, batch_obj->base.size);
994 
995 	cmd = batch_base + (batch_start_offset / sizeof(*cmd));
996 	batch_end = cmd + (batch_obj->base.size / sizeof(*batch_end));
997 
998 	while (cmd < batch_end) {
999 		const struct drm_i915_cmd_descriptor *desc;
1000 		u32 length;
1001 
1002 		if (*cmd == MI_BATCH_BUFFER_END)
1003 			break;
1004 
1005 		desc = find_cmd(ring, *cmd, &default_desc);
1006 		if (!desc) {
1007 			DRM_DEBUG_DRIVER("CMD: Unrecognized command: 0x%08X\n",
1008 					 *cmd);
1009 			ret = -EINVAL;
1010 			break;
1011 		}
1012 
1013 		/*
1014 		 * If the batch buffer contains a chained batch, return an
1015 		 * error that tells the caller to abort and dispatch the
1016 		 * workload as a non-secure batch.
1017 		 */
1018 		if (desc->cmd.value == MI_BATCH_BUFFER_START) {
1019 			ret = -EACCES;
1020 			break;
1021 		}
1022 
1023 		if (desc->flags & CMD_DESC_FIXED)
1024 			length = desc->length.fixed;
1025 		else
1026 			length = ((*cmd & desc->length.mask) + LENGTH_BIAS);
1027 
1028 		if ((batch_end - cmd) < length) {
1029 			DRM_DEBUG_DRIVER("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n",
1030 					 *cmd,
1031 					 length,
1032 					 batch_end - cmd);
1033 			ret = -EINVAL;
1034 			break;
1035 		}
1036 
1037 		if (!check_cmd(ring, desc, cmd, is_master, &oacontrol_set)) {
1038 			ret = -EINVAL;
1039 			break;
1040 		}
1041 
1042 		cmd += length;
1043 	}
1044 
1045 	if (oacontrol_set) {
1046 		DRM_DEBUG_DRIVER("CMD: batch set OACONTROL but did not clear it\n");
1047 		ret = -EINVAL;
1048 	}
1049 
1050 	if (cmd >= batch_end) {
1051 		DRM_DEBUG_DRIVER("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
1052 		ret = -EINVAL;
1053 	}
1054 
1055 	vunmap(batch_base);
1056 
1057 	i915_gem_object_unpin_pages(batch_obj);
1058 
1059 	return ret;
1060 }
1061 
1062 /**
1063  * i915_cmd_parser_get_version() - get the cmd parser version number
1064  *
1065  * The cmd parser maintains a simple increasing integer version number suitable
1066  * for passing to userspace clients to determine what operations are permitted.
1067  *
1068  * Return: the current version number of the cmd parser
1069  */
1070 int i915_cmd_parser_get_version(void)
1071 {
1072 	/*
1073 	 * Command parser version history
1074 	 *
1075 	 * 1. Initial version. Checks batches and reports violations, but leaves
1076 	 *    hardware parsing enabled (so does not allow new use cases).
1077 	 * 2. Allow access to the MI_PREDICATE_SRC0 and
1078 	 *    MI_PREDICATE_SRC1 registers.
1079 	 */
1080 	return 2;
1081 }
1082