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 #define range_overflows(start, size, max) ({ \
77 typeof(start) start__ = (start); \
78 typeof(size) size__ = (size); \
79 typeof(max) max__ = (max); \
80 (void)(&start__ == &size__); \
81 (void)(&start__ == &max__); \
82 start__ >= max__ || size__ > max__ - start__; \
83 })
84
85 #define range_overflows_t(type, start, size, max) \
86 range_overflows((type)(start), (type)(size), (type)(max))
87
88 #define range_overflows_end(start, size, max) ({ \
89 typeof(start) start__ = (start); \
90 typeof(size) size__ = (size); \
91 typeof(max) max__ = (max); \
92 (void)(&start__ == &size__); \
93 (void)(&start__ == &max__); \
94 start__ > max__ || size__ > max__ - start__; \
95 })
96
97 #define range_overflows_end_t(type, start, size, max) \
98 range_overflows_end((type)(start), (type)(size), (type)(max))
99
100 #define ptr_mask_bits(ptr, n) ({ \
101 unsigned long __v = (unsigned long)(ptr); \
102 (typeof(ptr))(__v & -BIT(n)); \
103 })
104
105 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1))
106
107 #define ptr_unpack_bits(ptr, bits, n) ({ \
108 unsigned long __v = (unsigned long)(ptr); \
109 *(bits) = __v & (BIT(n) - 1); \
110 (typeof(ptr))(__v & -BIT(n)); \
111 })
112
113 #define ptr_pack_bits(ptr, bits, n) ({ \
114 unsigned long __bits = (bits); \
115 GEM_BUG_ON(__bits & -BIT(n)); \
116 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \
117 })
118
119 #define ptr_dec(ptr) ({ \
120 unsigned long __v = (unsigned long)(ptr); \
121 (typeof(ptr))(__v - 1); \
122 })
123
124 #define ptr_inc(ptr) ({ \
125 unsigned long __v = (unsigned long)(ptr); \
126 (typeof(ptr))(__v + 1); \
127 })
128
129 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT)
130 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT)
131 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT)
132 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT)
133
134 #define fetch_and_zero(ptr) ({ \
135 typeof(*ptr) __T = *(ptr); \
136 *(ptr) = (typeof(*ptr))0; \
137 __T; \
138 })
139
ptrdiff(const void * a,const void * b)140 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b)
141 {
142 return a - b;
143 }
144
145 /*
146 * container_of_user: Extract the superclass from a pointer to a member.
147 *
148 * Exactly like container_of() with the exception that it plays nicely
149 * with sparse for __user @ptr.
150 */
151 #define container_of_user(ptr, type, member) ({ \
152 void __user *__mptr = (void __user *)(ptr); \
153 BUILD_BUG_ON_MSG(!__same_type(*(ptr), typeof_member(type, member)) && \
154 !__same_type(*(ptr), void), \
155 "pointer type mismatch in container_of()"); \
156 ((type __user *)(__mptr - offsetof(type, member))); })
157
158 /*
159 * check_user_mbz: Check that a user value exists and is zero
160 *
161 * Frequently in our uABI we reserve space for future extensions, and
162 * two ensure that userspace is prepared we enforce that space must
163 * be zero. (Then any future extension can safely assume a default value
164 * of 0.)
165 *
166 * check_user_mbz() combines checking that the user pointer is accessible
167 * and that the contained value is zero.
168 *
169 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success.
170 */
171 #define check_user_mbz(U) ({ \
172 typeof(*(U)) mbz__; \
173 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \
174 })
175
176 #define u64_to_ptr(T, x) ({ \
177 typecheck(u64, x); \
178 (T *)(uintptr_t)(x); \
179 })
180
181 #define __mask_next_bit(mask) ({ \
182 int __idx = ffs(mask) - 1; \
183 mask &= ~BIT(__idx); \
184 __idx; \
185 })
186
is_power_of_2_u64(u64 n)187 static inline bool is_power_of_2_u64(u64 n)
188 {
189 return (n != 0 && ((n & (n - 1)) == 0));
190 }
191
__list_del_many(struct list_head * head,struct list_head * first)192 static inline void __list_del_many(struct list_head *head,
193 struct list_head *first)
194 {
195 first->prev = head;
196 WRITE_ONCE(head->next, first);
197 }
198
list_is_last_rcu(const struct list_head * list,const struct list_head * head)199 static inline int list_is_last_rcu(const struct list_head *list,
200 const struct list_head *head)
201 {
202 return READ_ONCE(list->next) == head;
203 }
204
msecs_to_jiffies_timeout(const unsigned int m)205 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m)
206 {
207 unsigned long j = msecs_to_jiffies(m);
208
209 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1);
210 }
211
212 /*
213 * If you need to wait X milliseconds between events A and B, but event B
214 * doesn't happen exactly after event A, you record the timestamp (jiffies) of
215 * when event A happened, then just before event B you call this function and
216 * pass the timestamp as the first argument, and X as the second argument.
217 */
218 static inline void
wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies,int to_wait_ms)219 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms)
220 {
221 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies;
222
223 /*
224 * Don't re-read the value of "jiffies" every time since it may change
225 * behind our back and break the math.
226 */
227 tmp_jiffies = jiffies;
228 target_jiffies = timestamp_jiffies +
229 msecs_to_jiffies_timeout(to_wait_ms);
230
231 if (time_after(target_jiffies, tmp_jiffies)) {
232 remaining_jiffies = target_jiffies - tmp_jiffies;
233 while (remaining_jiffies)
234 remaining_jiffies =
235 schedule_timeout_uninterruptible(remaining_jiffies);
236 }
237 }
238
239 /*
240 * __wait_for - magic wait macro
241 *
242 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's
243 * important that we check the condition again after having timed out, since the
244 * timeout could be due to preemption or similar and we've never had a chance to
245 * check the condition before the timeout.
246 */
247 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \
248 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \
249 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \
250 int ret__; \
251 might_sleep(); \
252 for (;;) { \
253 const bool expired__ = ktime_after(ktime_get_raw(), end__); \
254 OP; \
255 /* Guarantee COND check prior to timeout */ \
256 barrier(); \
257 if (COND) { \
258 ret__ = 0; \
259 break; \
260 } \
261 if (expired__) { \
262 ret__ = -ETIMEDOUT; \
263 break; \
264 } \
265 usleep_range(wait__, wait__ * 2); \
266 if (wait__ < (Wmax)) \
267 wait__ <<= 1; \
268 } \
269 ret__; \
270 })
271
272 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \
273 (Wmax))
274 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000)
275
276 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */
277 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT)
278 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic())
279 #else
280 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0)
281 #endif
282
283 #define _wait_for_atomic(COND, US, ATOMIC) \
284 ({ \
285 int cpu, ret, timeout = (US) * 1000; \
286 u64 base; \
287 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \
288 if (!(ATOMIC)) { \
289 preempt_disable(); \
290 cpu = smp_processor_id(); \
291 } \
292 base = local_clock(); \
293 for (;;) { \
294 u64 now = local_clock(); \
295 if (!(ATOMIC)) \
296 preempt_enable(); \
297 /* Guarantee COND check prior to timeout */ \
298 barrier(); \
299 if (COND) { \
300 ret = 0; \
301 break; \
302 } \
303 if (now - base >= timeout) { \
304 ret = -ETIMEDOUT; \
305 break; \
306 } \
307 cpu_relax(); \
308 if (!(ATOMIC)) { \
309 preempt_disable(); \
310 if (unlikely(cpu != smp_processor_id())) { \
311 timeout -= now - base; \
312 cpu = smp_processor_id(); \
313 base = local_clock(); \
314 } \
315 } \
316 } \
317 ret; \
318 })
319
320 #define wait_for_us(COND, US) \
321 ({ \
322 int ret__; \
323 BUILD_BUG_ON(!__builtin_constant_p(US)); \
324 if ((US) > 10) \
325 ret__ = _wait_for((COND), (US), 10, 10); \
326 else \
327 ret__ = _wait_for_atomic((COND), (US), 0); \
328 ret__; \
329 })
330
331 #define wait_for_atomic_us(COND, US) \
332 ({ \
333 BUILD_BUG_ON(!__builtin_constant_p(US)); \
334 BUILD_BUG_ON((US) > 50000); \
335 _wait_for_atomic((COND), (US), 1); \
336 })
337
338 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000)
339
340 #define KHz(x) (1000 * (x))
341 #define MHz(x) KHz(1000 * (x))
342
343 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint);
__add_taint_for_CI(unsigned int taint)344 static inline void __add_taint_for_CI(unsigned int taint)
345 {
346 /*
347 * The system is "ok", just about surviving for the user, but
348 * CI results are now unreliable as the HW is very suspect.
349 * CI checks the taint state after every test and will reboot
350 * the machine if the kernel is tainted.
351 */
352 add_taint(taint, LOCKDEP_STILL_OK);
353 }
354
355 void cancel_timer(struct timer_list *t);
356 void set_timer_ms(struct timer_list *t, unsigned long timeout);
357
timer_active(const struct timer_list * t)358 static inline bool timer_active(const struct timer_list *t)
359 {
360 return READ_ONCE(t->expires);
361 }
362
timer_expired(const struct timer_list * t)363 static inline bool timer_expired(const struct timer_list *t)
364 {
365 return timer_active(t) && !timer_pending(t);
366 }
367
i915_run_as_guest(void)368 static inline bool i915_run_as_guest(void)
369 {
370 #if IS_ENABLED(CONFIG_X86)
371 return !hypervisor_is_type(X86_HYPER_NATIVE);
372 #else
373 /* Not supported yet */
374 return false;
375 #endif
376 }
377
378 bool i915_vtd_active(struct drm_i915_private *i915);
379
380 bool i915_direct_stolen_access(struct drm_i915_private *i915);
381
382 #endif /* !__I915_UTILS_H */
383