1 /*
2 * Copyright © 2016 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 */
24
25 #ifndef __I915_UTILS_H
26 #define __I915_UTILS_H
27
28 #include <linux/list.h>
29 #include <linux/overflow.h>
30 #include <linux/sched.h>
31 #include <linux/string_helpers.h>
32 #include <linux/types.h>
33 #include <linux/workqueue.h>
34 #include <linux/sched/clock.h>
35
36 #ifdef CONFIG_X86
37 #include <asm/hypervisor.h>
38 #endif
39
40 struct drm_i915_private;
41 struct timer_list;
42
43 #define FDO_BUG_URL "https://gitlab.freedesktop.org/drm/intel/-/wikis/How-to-file-i915-bugs"
44
45 #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
46 __stringify(x), (long)(x))
47
48 void __printf(3, 4)
49 __i915_printk(struct drm_i915_private *dev_priv, const char *level,
50 const char *fmt, ...);
51
52 #define i915_report_error(dev_priv, fmt, ...) \
53 __i915_printk(dev_priv, KERN_ERR, fmt, ##__VA_ARGS__)
54
55 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
56
57 int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
58 const char *func, int line);
59 #define i915_inject_probe_error(_i915, _err) \
60 __i915_inject_probe_error((_i915), (_err), __func__, __LINE__)
61 bool i915_error_injected(void);
62
63 #else
64
65 #define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; })
66 #define i915_error_injected() false
67
68 #endif
69
70 #define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV)
71
72 #define i915_probe_error(i915, fmt, ...) \
73 __i915_printk(i915, i915_error_injected() ? KERN_DEBUG : KERN_ERR, \
74 fmt, ##__VA_ARGS__)
75
76 #if defined(GCC_VERSION) && GCC_VERSION >= 70000
77 #define add_overflows_t(T, A, B) \
78 __builtin_add_overflow_p((A), (B), (T)0)
79 #else
80 #define add_overflows_t(T, A, B) ({ \
81 typeof(A) a = (A); \
82 typeof(B) b = (B); \
83 (T)(a + b) < a; \
84 })
85 #endif
86
87 #define add_overflows(A, B) \
88 add_overflows_t(typeof((A) + (B)), (A), (B))
89
90 #define range_overflows(start, size, max) ({ \
91 typeof(start) start__ = (start); \
92 typeof(size) size__ = (size); \
93 typeof(max) max__ = (max); \
94 (void)(&start__ == &size__); \
95 (void)(&start__ == &max__); \
96 start__ >= max__ || size__ > max__ - start__; \
97 })
98
99 #define range_overflows_t(type, start, size, max) \
100 range_overflows((type)(start), (type)(size), (type)(max))
101
102 #define range_overflows_end(start, size, max) ({ \
103 typeof(start) start__ = (start); \
104 typeof(size) size__ = (size); \
105 typeof(max) max__ = (max); \
106 (void)(&start__ == &size__); \
107 (void)(&start__ == &max__); \
108 start__ > max__ || size__ > max__ - start__; \
109 })
110
111 #define range_overflows_end_t(type, start, size, max) \
112 range_overflows_end((type)(start), (type)(size), (type)(max))
113
114 /* Note we don't consider signbits :| */
115 #define overflows_type(x, T) \
116 (sizeof(x) > sizeof(T) && (x) >> BITS_PER_TYPE(T))
117
118 static inline bool
__check_struct_size(size_t base,size_t arr,size_t count,size_t * size)119 __check_struct_size(size_t base, size_t arr, size_t count, size_t *size)
120 {
121 size_t sz;
122
123 if (check_mul_overflow(count, arr, &sz))
124 return false;
125
126 if (check_add_overflow(sz, base, &sz))
127 return false;
128
129 *size = sz;
130 return true;
131 }
132
133 /**
134 * check_struct_size() - Calculate size of structure with trailing array.
135 * @p: Pointer to the structure.
136 * @member: Name of the array member.
137 * @n: Number of elements in the array.
138 * @sz: Total size of structure and array
139 *
140 * Calculates size of memory needed for structure @p followed by an
141 * array of @n @member elements, like struct_size() but reports
142 * whether it overflowed, and the resultant size in @sz
143 *
144 * Return: false if the calculation overflowed.
145 */
146 #define check_struct_size(p, member, n, sz) \
147 likely(__check_struct_size(sizeof(*(p)), \
148 sizeof(*(p)->member) + __must_be_array((p)->member), \
149 n, sz))
150
151 #define ptr_mask_bits(ptr, n) ({ \
152 unsigned long __v = (unsigned long)(ptr); \
153 (typeof(ptr))(__v & -BIT(n)); \
154 })
155
156 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1))
157
158 #define ptr_unpack_bits(ptr, bits, n) ({ \
159 unsigned long __v = (unsigned long)(ptr); \
160 *(bits) = __v & (BIT(n) - 1); \
161 (typeof(ptr))(__v & -BIT(n)); \
162 })
163
164 #define ptr_pack_bits(ptr, bits, n) ({ \
165 unsigned long __bits = (bits); \
166 GEM_BUG_ON(__bits & -BIT(n)); \
167 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \
168 })
169
170 #define ptr_dec(ptr) ({ \
171 unsigned long __v = (unsigned long)(ptr); \
172 (typeof(ptr))(__v - 1); \
173 })
174
175 #define ptr_inc(ptr) ({ \
176 unsigned long __v = (unsigned long)(ptr); \
177 (typeof(ptr))(__v + 1); \
178 })
179
180 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT)
181 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT)
182 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT)
183 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT)
184
185 #define struct_member(T, member) (((T *)0)->member)
186
187 #define ptr_offset(ptr, member) offsetof(typeof(*(ptr)), member)
188
189 #define fetch_and_zero(ptr) ({ \
190 typeof(*ptr) __T = *(ptr); \
191 *(ptr) = (typeof(*ptr))0; \
192 __T; \
193 })
194
ptrdiff(const void * a,const void * b)195 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b)
196 {
197 return a - b;
198 }
199
200 /*
201 * container_of_user: Extract the superclass from a pointer to a member.
202 *
203 * Exactly like container_of() with the exception that it plays nicely
204 * with sparse for __user @ptr.
205 */
206 #define container_of_user(ptr, type, member) ({ \
207 void __user *__mptr = (void __user *)(ptr); \
208 BUILD_BUG_ON_MSG(!__same_type(*(ptr), struct_member(type, member)) && \
209 !__same_type(*(ptr), void), \
210 "pointer type mismatch in container_of()"); \
211 ((type __user *)(__mptr - offsetof(type, member))); })
212
213 /*
214 * check_user_mbz: Check that a user value exists and is zero
215 *
216 * Frequently in our uABI we reserve space for future extensions, and
217 * two ensure that userspace is prepared we enforce that space must
218 * be zero. (Then any future extension can safely assume a default value
219 * of 0.)
220 *
221 * check_user_mbz() combines checking that the user pointer is accessible
222 * and that the contained value is zero.
223 *
224 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success.
225 */
226 #define check_user_mbz(U) ({ \
227 typeof(*(U)) mbz__; \
228 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \
229 })
230
ptr_to_u64(const void * ptr)231 static inline u64 ptr_to_u64(const void *ptr)
232 {
233 return (uintptr_t)ptr;
234 }
235
236 #define u64_to_ptr(T, x) ({ \
237 typecheck(u64, x); \
238 (T *)(uintptr_t)(x); \
239 })
240
241 #define __mask_next_bit(mask) ({ \
242 int __idx = ffs(mask) - 1; \
243 mask &= ~BIT(__idx); \
244 __idx; \
245 })
246
is_power_of_2_u64(u64 n)247 static inline bool is_power_of_2_u64(u64 n)
248 {
249 return (n != 0 && ((n & (n - 1)) == 0));
250 }
251
__list_del_many(struct list_head * head,struct list_head * first)252 static inline void __list_del_many(struct list_head *head,
253 struct list_head *first)
254 {
255 first->prev = head;
256 WRITE_ONCE(head->next, first);
257 }
258
list_is_last_rcu(const struct list_head * list,const struct list_head * head)259 static inline int list_is_last_rcu(const struct list_head *list,
260 const struct list_head *head)
261 {
262 return READ_ONCE(list->next) == head;
263 }
264
msecs_to_jiffies_timeout(const unsigned int m)265 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
266 {
267 unsigned long j = msecs_to_jiffies(m);
268
269 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
270 }
271
272 /*
273 * If you need to wait X milliseconds between events A and B, but event B
274 * doesn't happen exactly after event A, you record the timestamp (jiffies) of
275 * when event A happened, then just before event B you call this function and
276 * pass the timestamp as the first argument, and X as the second argument.
277 */
278 static inline void
wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies,int to_wait_ms)279 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms)
280 {
281 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies;
282
283 /*
284 * Don't re-read the value of "jiffies" every time since it may change
285 * behind our back and break the math.
286 */
287 tmp_jiffies = jiffies;
288 target_jiffies = timestamp_jiffies +
289 msecs_to_jiffies_timeout(to_wait_ms);
290
291 if (time_after(target_jiffies, tmp_jiffies)) {
292 remaining_jiffies = target_jiffies - tmp_jiffies;
293 while (remaining_jiffies)
294 remaining_jiffies =
295 schedule_timeout_uninterruptible(remaining_jiffies);
296 }
297 }
298
299 /**
300 * __wait_for - magic wait macro
301 *
302 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's
303 * important that we check the condition again after having timed out, since the
304 * timeout could be due to preemption or similar and we've never had a chance to
305 * check the condition before the timeout.
306 */
307 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \
308 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \
309 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \
310 int ret__; \
311 might_sleep(); \
312 for (;;) { \
313 const bool expired__ = ktime_after(ktime_get_raw(), end__); \
314 OP; \
315 /* Guarantee COND check prior to timeout */ \
316 barrier(); \
317 if (COND) { \
318 ret__ = 0; \
319 break; \
320 } \
321 if (expired__) { \
322 ret__ = -ETIMEDOUT; \
323 break; \
324 } \
325 usleep_range(wait__, wait__ * 2); \
326 if (wait__ < (Wmax)) \
327 wait__ <<= 1; \
328 } \
329 ret__; \
330 })
331
332 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \
333 (Wmax))
334 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000)
335
336 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */
337 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT)
338 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic())
339 #else
340 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0)
341 #endif
342
343 #define _wait_for_atomic(COND, US, ATOMIC) \
344 ({ \
345 int cpu, ret, timeout = (US) * 1000; \
346 u64 base; \
347 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \
348 if (!(ATOMIC)) { \
349 preempt_disable(); \
350 cpu = smp_processor_id(); \
351 } \
352 base = local_clock(); \
353 for (;;) { \
354 u64 now = local_clock(); \
355 if (!(ATOMIC)) \
356 preempt_enable(); \
357 /* Guarantee COND check prior to timeout */ \
358 barrier(); \
359 if (COND) { \
360 ret = 0; \
361 break; \
362 } \
363 if (now - base >= timeout) { \
364 ret = -ETIMEDOUT; \
365 break; \
366 } \
367 cpu_relax(); \
368 if (!(ATOMIC)) { \
369 preempt_disable(); \
370 if (unlikely(cpu != smp_processor_id())) { \
371 timeout -= now - base; \
372 cpu = smp_processor_id(); \
373 base = local_clock(); \
374 } \
375 } \
376 } \
377 ret; \
378 })
379
380 #define wait_for_us(COND, US) \
381 ({ \
382 int ret__; \
383 BUILD_BUG_ON(!__builtin_constant_p(US)); \
384 if ((US) > 10) \
385 ret__ = _wait_for((COND), (US), 10, 10); \
386 else \
387 ret__ = _wait_for_atomic((COND), (US), 0); \
388 ret__; \
389 })
390
391 #define wait_for_atomic_us(COND, US) \
392 ({ \
393 BUILD_BUG_ON(!__builtin_constant_p(US)); \
394 BUILD_BUG_ON((US) > 50000); \
395 _wait_for_atomic((COND), (US), 1); \
396 })
397
398 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000)
399
400 #define KHz(x) (1000 * (x))
401 #define MHz(x) KHz(1000 * (x))
402
403 #define KBps(x) (1000 * (x))
404 #define MBps(x) KBps(1000 * (x))
405 #define GBps(x) ((u64)1000 * MBps((x)))
406
407 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint);
__add_taint_for_CI(unsigned int taint)408 static inline void __add_taint_for_CI(unsigned int taint)
409 {
410 /*
411 * The system is "ok", just about surviving for the user, but
412 * CI results are now unreliable as the HW is very suspect.
413 * CI checks the taint state after every test and will reboot
414 * the machine if the kernel is tainted.
415 */
416 add_taint(taint, LOCKDEP_STILL_OK);
417 }
418
419 void cancel_timer(struct timer_list *t);
420 void set_timer_ms(struct timer_list *t, unsigned long timeout);
421
timer_active(const struct timer_list * t)422 static inline bool timer_active(const struct timer_list *t)
423 {
424 return READ_ONCE(t->expires);
425 }
426
timer_expired(const struct timer_list * t)427 static inline bool timer_expired(const struct timer_list *t)
428 {
429 return timer_active(t) && !timer_pending(t);
430 }
431
i915_run_as_guest(void)432 static inline bool i915_run_as_guest(void)
433 {
434 #if IS_ENABLED(CONFIG_X86)
435 return !hypervisor_is_type(X86_HYPER_NATIVE);
436 #else
437 /* Not supported yet */
438 return false;
439 #endif
440 }
441
442 bool i915_vtd_active(struct drm_i915_private *i915);
443
444 #endif /* !__I915_UTILS_H */
445