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/types.h> 32 #include <linux/workqueue.h> 33 #include <linux/sched/clock.h> 34 35 struct drm_i915_private; 36 struct timer_list; 37 38 #define FDO_BUG_URL "https://gitlab.freedesktop.org/drm/intel/-/wikis/How-to-file-i915-bugs" 39 40 #undef WARN_ON 41 /* Many gcc seem to no see through this and fall over :( */ 42 #if 0 43 #define WARN_ON(x) ({ \ 44 bool __i915_warn_cond = (x); \ 45 if (__builtin_constant_p(__i915_warn_cond)) \ 46 BUILD_BUG_ON(__i915_warn_cond); \ 47 WARN(__i915_warn_cond, "WARN_ON(" #x ")"); }) 48 #else 49 #define WARN_ON(x) WARN((x), "%s", "WARN_ON(" __stringify(x) ")") 50 #endif 51 52 #undef WARN_ON_ONCE 53 #define WARN_ON_ONCE(x) WARN_ONCE((x), "%s", "WARN_ON_ONCE(" __stringify(x) ")") 54 55 #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \ 56 __stringify(x), (long)(x)) 57 58 void __printf(3, 4) 59 __i915_printk(struct drm_i915_private *dev_priv, const char *level, 60 const char *fmt, ...); 61 62 #define i915_report_error(dev_priv, fmt, ...) \ 63 __i915_printk(dev_priv, KERN_ERR, fmt, ##__VA_ARGS__) 64 65 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 66 67 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 68 const char *func, int line); 69 #define i915_inject_probe_error(_i915, _err) \ 70 __i915_inject_probe_error((_i915), (_err), __func__, __LINE__) 71 bool i915_error_injected(void); 72 73 #else 74 75 #define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; }) 76 #define i915_error_injected() false 77 78 #endif 79 80 #define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV) 81 82 #define i915_probe_error(i915, fmt, ...) \ 83 __i915_printk(i915, i915_error_injected() ? KERN_DEBUG : KERN_ERR, \ 84 fmt, ##__VA_ARGS__) 85 86 #if defined(GCC_VERSION) && GCC_VERSION >= 70000 87 #define add_overflows_t(T, A, B) \ 88 __builtin_add_overflow_p((A), (B), (T)0) 89 #else 90 #define add_overflows_t(T, A, B) ({ \ 91 typeof(A) a = (A); \ 92 typeof(B) b = (B); \ 93 (T)(a + b) < a; \ 94 }) 95 #endif 96 97 #define add_overflows(A, B) \ 98 add_overflows_t(typeof((A) + (B)), (A), (B)) 99 100 #define range_overflows(start, size, max) ({ \ 101 typeof(start) start__ = (start); \ 102 typeof(size) size__ = (size); \ 103 typeof(max) max__ = (max); \ 104 (void)(&start__ == &size__); \ 105 (void)(&start__ == &max__); \ 106 start__ >= max__ || size__ > max__ - start__; \ 107 }) 108 109 #define range_overflows_t(type, start, size, max) \ 110 range_overflows((type)(start), (type)(size), (type)(max)) 111 112 #define range_overflows_end(start, size, max) ({ \ 113 typeof(start) start__ = (start); \ 114 typeof(size) size__ = (size); \ 115 typeof(max) max__ = (max); \ 116 (void)(&start__ == &size__); \ 117 (void)(&start__ == &max__); \ 118 start__ > max__ || size__ > max__ - start__; \ 119 }) 120 121 #define range_overflows_end_t(type, start, size, max) \ 122 range_overflows_end((type)(start), (type)(size), (type)(max)) 123 124 /* Note we don't consider signbits :| */ 125 #define overflows_type(x, T) \ 126 (sizeof(x) > sizeof(T) && (x) >> BITS_PER_TYPE(T)) 127 128 static inline bool 129 __check_struct_size(size_t base, size_t arr, size_t count, size_t *size) 130 { 131 size_t sz; 132 133 if (check_mul_overflow(count, arr, &sz)) 134 return false; 135 136 if (check_add_overflow(sz, base, &sz)) 137 return false; 138 139 *size = sz; 140 return true; 141 } 142 143 /** 144 * check_struct_size() - Calculate size of structure with trailing array. 145 * @p: Pointer to the structure. 146 * @member: Name of the array member. 147 * @n: Number of elements in the array. 148 * @sz: Total size of structure and array 149 * 150 * Calculates size of memory needed for structure @p followed by an 151 * array of @n @member elements, like struct_size() but reports 152 * whether it overflowed, and the resultant size in @sz 153 * 154 * Return: false if the calculation overflowed. 155 */ 156 #define check_struct_size(p, member, n, sz) \ 157 likely(__check_struct_size(sizeof(*(p)), \ 158 sizeof(*(p)->member) + __must_be_array((p)->member), \ 159 n, sz)) 160 161 #define ptr_mask_bits(ptr, n) ({ \ 162 unsigned long __v = (unsigned long)(ptr); \ 163 (typeof(ptr))(__v & -BIT(n)); \ 164 }) 165 166 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 167 168 #define ptr_unpack_bits(ptr, bits, n) ({ \ 169 unsigned long __v = (unsigned long)(ptr); \ 170 *(bits) = __v & (BIT(n) - 1); \ 171 (typeof(ptr))(__v & -BIT(n)); \ 172 }) 173 174 #define ptr_pack_bits(ptr, bits, n) ({ \ 175 unsigned long __bits = (bits); \ 176 GEM_BUG_ON(__bits & -BIT(n)); \ 177 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \ 178 }) 179 180 #define ptr_dec(ptr) ({ \ 181 unsigned long __v = (unsigned long)(ptr); \ 182 (typeof(ptr))(__v - 1); \ 183 }) 184 185 #define ptr_inc(ptr) ({ \ 186 unsigned long __v = (unsigned long)(ptr); \ 187 (typeof(ptr))(__v + 1); \ 188 }) 189 190 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 191 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 192 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 193 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 194 195 #define struct_member(T, member) (((T *)0)->member) 196 197 #define ptr_offset(ptr, member) offsetof(typeof(*(ptr)), member) 198 199 #define fetch_and_zero(ptr) ({ \ 200 typeof(*ptr) __T = *(ptr); \ 201 *(ptr) = (typeof(*ptr))0; \ 202 __T; \ 203 }) 204 205 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b) 206 { 207 return a - b; 208 } 209 210 /* 211 * container_of_user: Extract the superclass from a pointer to a member. 212 * 213 * Exactly like container_of() with the exception that it plays nicely 214 * with sparse for __user @ptr. 215 */ 216 #define container_of_user(ptr, type, member) ({ \ 217 void __user *__mptr = (void __user *)(ptr); \ 218 BUILD_BUG_ON_MSG(!__same_type(*(ptr), struct_member(type, member)) && \ 219 !__same_type(*(ptr), void), \ 220 "pointer type mismatch in container_of()"); \ 221 ((type __user *)(__mptr - offsetof(type, member))); }) 222 223 /* 224 * check_user_mbz: Check that a user value exists and is zero 225 * 226 * Frequently in our uABI we reserve space for future extensions, and 227 * two ensure that userspace is prepared we enforce that space must 228 * be zero. (Then any future extension can safely assume a default value 229 * of 0.) 230 * 231 * check_user_mbz() combines checking that the user pointer is accessible 232 * and that the contained value is zero. 233 * 234 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 235 */ 236 #define check_user_mbz(U) ({ \ 237 typeof(*(U)) mbz__; \ 238 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 239 }) 240 241 static inline u64 ptr_to_u64(const void *ptr) 242 { 243 return (uintptr_t)ptr; 244 } 245 246 #define u64_to_ptr(T, x) ({ \ 247 typecheck(u64, x); \ 248 (T *)(uintptr_t)(x); \ 249 }) 250 251 #define __mask_next_bit(mask) ({ \ 252 int __idx = ffs(mask) - 1; \ 253 mask &= ~BIT(__idx); \ 254 __idx; \ 255 }) 256 257 static inline bool is_power_of_2_u64(u64 n) 258 { 259 return (n != 0 && ((n & (n - 1)) == 0)); 260 } 261 262 static inline void __list_del_many(struct list_head *head, 263 struct list_head *first) 264 { 265 first->prev = head; 266 WRITE_ONCE(head->next, first); 267 } 268 269 static inline int list_is_last_rcu(const struct list_head *list, 270 const struct list_head *head) 271 { 272 return READ_ONCE(list->next) == head; 273 } 274 275 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 276 { 277 unsigned long j = msecs_to_jiffies(m); 278 279 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 280 } 281 282 /* 283 * If you need to wait X milliseconds between events A and B, but event B 284 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 285 * when event A happened, then just before event B you call this function and 286 * pass the timestamp as the first argument, and X as the second argument. 287 */ 288 static inline void 289 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 290 { 291 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 292 293 /* 294 * Don't re-read the value of "jiffies" every time since it may change 295 * behind our back and break the math. 296 */ 297 tmp_jiffies = jiffies; 298 target_jiffies = timestamp_jiffies + 299 msecs_to_jiffies_timeout(to_wait_ms); 300 301 if (time_after(target_jiffies, tmp_jiffies)) { 302 remaining_jiffies = target_jiffies - tmp_jiffies; 303 while (remaining_jiffies) 304 remaining_jiffies = 305 schedule_timeout_uninterruptible(remaining_jiffies); 306 } 307 } 308 309 /** 310 * __wait_for - magic wait macro 311 * 312 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 313 * important that we check the condition again after having timed out, since the 314 * timeout could be due to preemption or similar and we've never had a chance to 315 * check the condition before the timeout. 316 */ 317 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 318 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 319 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 320 int ret__; \ 321 might_sleep(); \ 322 for (;;) { \ 323 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 324 OP; \ 325 /* Guarantee COND check prior to timeout */ \ 326 barrier(); \ 327 if (COND) { \ 328 ret__ = 0; \ 329 break; \ 330 } \ 331 if (expired__) { \ 332 ret__ = -ETIMEDOUT; \ 333 break; \ 334 } \ 335 usleep_range(wait__, wait__ * 2); \ 336 if (wait__ < (Wmax)) \ 337 wait__ <<= 1; \ 338 } \ 339 ret__; \ 340 }) 341 342 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 343 (Wmax)) 344 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 345 346 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 347 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 348 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 349 #else 350 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 351 #endif 352 353 #define _wait_for_atomic(COND, US, ATOMIC) \ 354 ({ \ 355 int cpu, ret, timeout = (US) * 1000; \ 356 u64 base; \ 357 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 358 if (!(ATOMIC)) { \ 359 preempt_disable(); \ 360 cpu = smp_processor_id(); \ 361 } \ 362 base = local_clock(); \ 363 for (;;) { \ 364 u64 now = local_clock(); \ 365 if (!(ATOMIC)) \ 366 preempt_enable(); \ 367 /* Guarantee COND check prior to timeout */ \ 368 barrier(); \ 369 if (COND) { \ 370 ret = 0; \ 371 break; \ 372 } \ 373 if (now - base >= timeout) { \ 374 ret = -ETIMEDOUT; \ 375 break; \ 376 } \ 377 cpu_relax(); \ 378 if (!(ATOMIC)) { \ 379 preempt_disable(); \ 380 if (unlikely(cpu != smp_processor_id())) { \ 381 timeout -= now - base; \ 382 cpu = smp_processor_id(); \ 383 base = local_clock(); \ 384 } \ 385 } \ 386 } \ 387 ret; \ 388 }) 389 390 #define wait_for_us(COND, US) \ 391 ({ \ 392 int ret__; \ 393 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 394 if ((US) > 10) \ 395 ret__ = _wait_for((COND), (US), 10, 10); \ 396 else \ 397 ret__ = _wait_for_atomic((COND), (US), 0); \ 398 ret__; \ 399 }) 400 401 #define wait_for_atomic_us(COND, US) \ 402 ({ \ 403 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 404 BUILD_BUG_ON((US) > 50000); \ 405 _wait_for_atomic((COND), (US), 1); \ 406 }) 407 408 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 409 410 #define KHz(x) (1000 * (x)) 411 #define MHz(x) KHz(1000 * (x)) 412 413 #define KBps(x) (1000 * (x)) 414 #define MBps(x) KBps(1000 * (x)) 415 #define GBps(x) ((u64)1000 * MBps((x))) 416 417 static inline const char *yesno(bool v) 418 { 419 return v ? "yes" : "no"; 420 } 421 422 static inline const char *onoff(bool v) 423 { 424 return v ? "on" : "off"; 425 } 426 427 static inline const char *enabledisable(bool v) 428 { 429 return v ? "enable" : "disable"; 430 } 431 432 static inline const char *enableddisabled(bool v) 433 { 434 return v ? "enabled" : "disabled"; 435 } 436 437 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint); 438 static inline void __add_taint_for_CI(unsigned int taint) 439 { 440 /* 441 * The system is "ok", just about surviving for the user, but 442 * CI results are now unreliable as the HW is very suspect. 443 * CI checks the taint state after every test and will reboot 444 * the machine if the kernel is tainted. 445 */ 446 add_taint(taint, LOCKDEP_STILL_OK); 447 } 448 449 void cancel_timer(struct timer_list *t); 450 void set_timer_ms(struct timer_list *t, unsigned long timeout); 451 452 static inline bool timer_active(const struct timer_list *t) 453 { 454 return READ_ONCE(t->expires); 455 } 456 457 static inline bool timer_expired(const struct timer_list *t) 458 { 459 return timer_active(t) && !timer_pending(t); 460 } 461 462 #endif /* !__I915_UTILS_H */ 463