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://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html"
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 #define ptr_mask_bits(ptr, n) ({ \
115 unsigned long __v = (unsigned long)(ptr); \
116 (typeof(ptr))(__v & -BIT(n)); \
117 })
118
119 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1))
120
121 #define ptr_unpack_bits(ptr, bits, n) ({ \
122 unsigned long __v = (unsigned long)(ptr); \
123 *(bits) = __v & (BIT(n) - 1); \
124 (typeof(ptr))(__v & -BIT(n)); \
125 })
126
127 #define ptr_pack_bits(ptr, bits, n) ({ \
128 unsigned long __bits = (bits); \
129 GEM_BUG_ON(__bits & -BIT(n)); \
130 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \
131 })
132
133 #define ptr_dec(ptr) ({ \
134 unsigned long __v = (unsigned long)(ptr); \
135 (typeof(ptr))(__v - 1); \
136 })
137
138 #define ptr_inc(ptr) ({ \
139 unsigned long __v = (unsigned long)(ptr); \
140 (typeof(ptr))(__v + 1); \
141 })
142
143 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT)
144 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT)
145 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT)
146 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT)
147
148 #define fetch_and_zero(ptr) ({ \
149 typeof(*ptr) __T = *(ptr); \
150 *(ptr) = (typeof(*ptr))0; \
151 __T; \
152 })
153
ptrdiff(const void * a,const void * b)154 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b)
155 {
156 return a - b;
157 }
158
159 /*
160 * container_of_user: Extract the superclass from a pointer to a member.
161 *
162 * Exactly like container_of() with the exception that it plays nicely
163 * with sparse for __user @ptr.
164 */
165 #define container_of_user(ptr, type, member) ({ \
166 void __user *__mptr = (void __user *)(ptr); \
167 BUILD_BUG_ON_MSG(!__same_type(*(ptr), typeof_member(type, member)) && \
168 !__same_type(*(ptr), void), \
169 "pointer type mismatch in container_of()"); \
170 ((type __user *)(__mptr - offsetof(type, member))); })
171
172 /*
173 * check_user_mbz: Check that a user value exists and is zero
174 *
175 * Frequently in our uABI we reserve space for future extensions, and
176 * two ensure that userspace is prepared we enforce that space must
177 * be zero. (Then any future extension can safely assume a default value
178 * of 0.)
179 *
180 * check_user_mbz() combines checking that the user pointer is accessible
181 * and that the contained value is zero.
182 *
183 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success.
184 */
185 #define check_user_mbz(U) ({ \
186 typeof(*(U)) mbz__; \
187 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \
188 })
189
190 #define u64_to_ptr(T, x) ({ \
191 typecheck(u64, x); \
192 (T *)(uintptr_t)(x); \
193 })
194
195 #define __mask_next_bit(mask) ({ \
196 int __idx = ffs(mask) - 1; \
197 mask &= ~BIT(__idx); \
198 __idx; \
199 })
200
is_power_of_2_u64(u64 n)201 static inline bool is_power_of_2_u64(u64 n)
202 {
203 return (n != 0 && ((n & (n - 1)) == 0));
204 }
205
__list_del_many(struct list_head * head,struct list_head * first)206 static inline void __list_del_many(struct list_head *head,
207 struct list_head *first)
208 {
209 first->prev = head;
210 WRITE_ONCE(head->next, first);
211 }
212
list_is_last_rcu(const struct list_head * list,const struct list_head * head)213 static inline int list_is_last_rcu(const struct list_head *list,
214 const struct list_head *head)
215 {
216 return READ_ONCE(list->next) == head;
217 }
218
msecs_to_jiffies_timeout(const unsigned int m)219 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
220 {
221 unsigned long j = msecs_to_jiffies(m);
222
223 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
224 }
225
226 /*
227 * If you need to wait X milliseconds between events A and B, but event B
228 * doesn't happen exactly after event A, you record the timestamp (jiffies) of
229 * when event A happened, then just before event B you call this function and
230 * pass the timestamp as the first argument, and X as the second argument.
231 */
232 static inline void
wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies,int to_wait_ms)233 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms)
234 {
235 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies;
236
237 /*
238 * Don't re-read the value of "jiffies" every time since it may change
239 * behind our back and break the math.
240 */
241 tmp_jiffies = jiffies;
242 target_jiffies = timestamp_jiffies +
243 msecs_to_jiffies_timeout(to_wait_ms);
244
245 if (time_after(target_jiffies, tmp_jiffies)) {
246 remaining_jiffies = target_jiffies - tmp_jiffies;
247 while (remaining_jiffies)
248 remaining_jiffies =
249 schedule_timeout_uninterruptible(remaining_jiffies);
250 }
251 }
252
253 /*
254 * __wait_for - magic wait macro
255 *
256 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's
257 * important that we check the condition again after having timed out, since the
258 * timeout could be due to preemption or similar and we've never had a chance to
259 * check the condition before the timeout.
260 */
261 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \
262 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \
263 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \
264 int ret__; \
265 might_sleep(); \
266 for (;;) { \
267 const bool expired__ = ktime_after(ktime_get_raw(), end__); \
268 OP; \
269 /* Guarantee COND check prior to timeout */ \
270 barrier(); \
271 if (COND) { \
272 ret__ = 0; \
273 break; \
274 } \
275 if (expired__) { \
276 ret__ = -ETIMEDOUT; \
277 break; \
278 } \
279 usleep_range(wait__, wait__ * 2); \
280 if (wait__ < (Wmax)) \
281 wait__ <<= 1; \
282 } \
283 ret__; \
284 })
285
286 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \
287 (Wmax))
288 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000)
289
290 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */
291 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT)
292 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic())
293 #else
294 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0)
295 #endif
296
297 #define _wait_for_atomic(COND, US, ATOMIC) \
298 ({ \
299 int cpu, ret, timeout = (US) * 1000; \
300 u64 base; \
301 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \
302 if (!(ATOMIC)) { \
303 preempt_disable(); \
304 cpu = smp_processor_id(); \
305 } \
306 base = local_clock(); \
307 for (;;) { \
308 u64 now = local_clock(); \
309 if (!(ATOMIC)) \
310 preempt_enable(); \
311 /* Guarantee COND check prior to timeout */ \
312 barrier(); \
313 if (COND) { \
314 ret = 0; \
315 break; \
316 } \
317 if (now - base >= timeout) { \
318 ret = -ETIMEDOUT; \
319 break; \
320 } \
321 cpu_relax(); \
322 if (!(ATOMIC)) { \
323 preempt_disable(); \
324 if (unlikely(cpu != smp_processor_id())) { \
325 timeout -= now - base; \
326 cpu = smp_processor_id(); \
327 base = local_clock(); \
328 } \
329 } \
330 } \
331 ret; \
332 })
333
334 #define wait_for_us(COND, US) \
335 ({ \
336 int ret__; \
337 BUILD_BUG_ON(!__builtin_constant_p(US)); \
338 if ((US) > 10) \
339 ret__ = _wait_for((COND), (US), 10, 10); \
340 else \
341 ret__ = _wait_for_atomic((COND), (US), 0); \
342 ret__; \
343 })
344
345 #define wait_for_atomic_us(COND, US) \
346 ({ \
347 BUILD_BUG_ON(!__builtin_constant_p(US)); \
348 BUILD_BUG_ON((US) > 50000); \
349 _wait_for_atomic((COND), (US), 1); \
350 })
351
352 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000)
353
354 #define KHz(x) (1000 * (x))
355 #define MHz(x) KHz(1000 * (x))
356
357 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint);
__add_taint_for_CI(unsigned int taint)358 static inline void __add_taint_for_CI(unsigned int taint)
359 {
360 /*
361 * The system is "ok", just about surviving for the user, but
362 * CI results are now unreliable as the HW is very suspect.
363 * CI checks the taint state after every test and will reboot
364 * the machine if the kernel is tainted.
365 */
366 add_taint(taint, LOCKDEP_STILL_OK);
367 }
368
369 void cancel_timer(struct timer_list *t);
370 void set_timer_ms(struct timer_list *t, unsigned long timeout);
371
timer_active(const struct timer_list * t)372 static inline bool timer_active(const struct timer_list *t)
373 {
374 return READ_ONCE(t->expires);
375 }
376
timer_expired(const struct timer_list * t)377 static inline bool timer_expired(const struct timer_list *t)
378 {
379 return timer_active(t) && !timer_pending(t);
380 }
381
i915_run_as_guest(void)382 static inline bool i915_run_as_guest(void)
383 {
384 #if IS_ENABLED(CONFIG_X86)
385 return !hypervisor_is_type(X86_HYPER_NATIVE);
386 #else
387 /* Not supported yet */
388 return false;
389 #endif
390 }
391
392 bool i915_vtd_active(struct drm_i915_private *i915);
393
394 #endif /* !__I915_UTILS_H */
395