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 #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 struct_member(T, member) (((T *)0)->member) 149 150 #define fetch_and_zero(ptr) ({ \ 151 typeof(*ptr) __T = *(ptr); \ 152 *(ptr) = (typeof(*ptr))0; \ 153 __T; \ 154 }) 155 156 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b) 157 { 158 return a - b; 159 } 160 161 /* 162 * container_of_user: Extract the superclass from a pointer to a member. 163 * 164 * Exactly like container_of() with the exception that it plays nicely 165 * with sparse for __user @ptr. 166 */ 167 #define container_of_user(ptr, type, member) ({ \ 168 void __user *__mptr = (void __user *)(ptr); \ 169 BUILD_BUG_ON_MSG(!__same_type(*(ptr), struct_member(type, member)) && \ 170 !__same_type(*(ptr), void), \ 171 "pointer type mismatch in container_of()"); \ 172 ((type __user *)(__mptr - offsetof(type, member))); }) 173 174 /* 175 * check_user_mbz: Check that a user value exists and is zero 176 * 177 * Frequently in our uABI we reserve space for future extensions, and 178 * two ensure that userspace is prepared we enforce that space must 179 * be zero. (Then any future extension can safely assume a default value 180 * of 0.) 181 * 182 * check_user_mbz() combines checking that the user pointer is accessible 183 * and that the contained value is zero. 184 * 185 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 186 */ 187 #define check_user_mbz(U) ({ \ 188 typeof(*(U)) mbz__; \ 189 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 190 }) 191 192 #define u64_to_ptr(T, x) ({ \ 193 typecheck(u64, x); \ 194 (T *)(uintptr_t)(x); \ 195 }) 196 197 #define __mask_next_bit(mask) ({ \ 198 int __idx = ffs(mask) - 1; \ 199 mask &= ~BIT(__idx); \ 200 __idx; \ 201 }) 202 203 static inline bool is_power_of_2_u64(u64 n) 204 { 205 return (n != 0 && ((n & (n - 1)) == 0)); 206 } 207 208 static inline void __list_del_many(struct list_head *head, 209 struct list_head *first) 210 { 211 first->prev = head; 212 WRITE_ONCE(head->next, first); 213 } 214 215 static inline int list_is_last_rcu(const struct list_head *list, 216 const struct list_head *head) 217 { 218 return READ_ONCE(list->next) == head; 219 } 220 221 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 222 { 223 unsigned long j = msecs_to_jiffies(m); 224 225 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 226 } 227 228 /* 229 * If you need to wait X milliseconds between events A and B, but event B 230 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 231 * when event A happened, then just before event B you call this function and 232 * pass the timestamp as the first argument, and X as the second argument. 233 */ 234 static inline void 235 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 236 { 237 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 238 239 /* 240 * Don't re-read the value of "jiffies" every time since it may change 241 * behind our back and break the math. 242 */ 243 tmp_jiffies = jiffies; 244 target_jiffies = timestamp_jiffies + 245 msecs_to_jiffies_timeout(to_wait_ms); 246 247 if (time_after(target_jiffies, tmp_jiffies)) { 248 remaining_jiffies = target_jiffies - tmp_jiffies; 249 while (remaining_jiffies) 250 remaining_jiffies = 251 schedule_timeout_uninterruptible(remaining_jiffies); 252 } 253 } 254 255 /** 256 * __wait_for - magic wait macro 257 * 258 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 259 * important that we check the condition again after having timed out, since the 260 * timeout could be due to preemption or similar and we've never had a chance to 261 * check the condition before the timeout. 262 */ 263 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 264 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 265 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 266 int ret__; \ 267 might_sleep(); \ 268 for (;;) { \ 269 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 270 OP; \ 271 /* Guarantee COND check prior to timeout */ \ 272 barrier(); \ 273 if (COND) { \ 274 ret__ = 0; \ 275 break; \ 276 } \ 277 if (expired__) { \ 278 ret__ = -ETIMEDOUT; \ 279 break; \ 280 } \ 281 usleep_range(wait__, wait__ * 2); \ 282 if (wait__ < (Wmax)) \ 283 wait__ <<= 1; \ 284 } \ 285 ret__; \ 286 }) 287 288 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 289 (Wmax)) 290 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 291 292 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 293 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 294 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 295 #else 296 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 297 #endif 298 299 #define _wait_for_atomic(COND, US, ATOMIC) \ 300 ({ \ 301 int cpu, ret, timeout = (US) * 1000; \ 302 u64 base; \ 303 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 304 if (!(ATOMIC)) { \ 305 preempt_disable(); \ 306 cpu = smp_processor_id(); \ 307 } \ 308 base = local_clock(); \ 309 for (;;) { \ 310 u64 now = local_clock(); \ 311 if (!(ATOMIC)) \ 312 preempt_enable(); \ 313 /* Guarantee COND check prior to timeout */ \ 314 barrier(); \ 315 if (COND) { \ 316 ret = 0; \ 317 break; \ 318 } \ 319 if (now - base >= timeout) { \ 320 ret = -ETIMEDOUT; \ 321 break; \ 322 } \ 323 cpu_relax(); \ 324 if (!(ATOMIC)) { \ 325 preempt_disable(); \ 326 if (unlikely(cpu != smp_processor_id())) { \ 327 timeout -= now - base; \ 328 cpu = smp_processor_id(); \ 329 base = local_clock(); \ 330 } \ 331 } \ 332 } \ 333 ret; \ 334 }) 335 336 #define wait_for_us(COND, US) \ 337 ({ \ 338 int ret__; \ 339 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 340 if ((US) > 10) \ 341 ret__ = _wait_for((COND), (US), 10, 10); \ 342 else \ 343 ret__ = _wait_for_atomic((COND), (US), 0); \ 344 ret__; \ 345 }) 346 347 #define wait_for_atomic_us(COND, US) \ 348 ({ \ 349 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 350 BUILD_BUG_ON((US) > 50000); \ 351 _wait_for_atomic((COND), (US), 1); \ 352 }) 353 354 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 355 356 #define KHz(x) (1000 * (x)) 357 #define MHz(x) KHz(1000 * (x)) 358 359 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint); 360 static inline void __add_taint_for_CI(unsigned int taint) 361 { 362 /* 363 * The system is "ok", just about surviving for the user, but 364 * CI results are now unreliable as the HW is very suspect. 365 * CI checks the taint state after every test and will reboot 366 * the machine if the kernel is tainted. 367 */ 368 add_taint(taint, LOCKDEP_STILL_OK); 369 } 370 371 void cancel_timer(struct timer_list *t); 372 void set_timer_ms(struct timer_list *t, unsigned long timeout); 373 374 static inline bool timer_active(const struct timer_list *t) 375 { 376 return READ_ONCE(t->expires); 377 } 378 379 static inline bool timer_expired(const struct timer_list *t) 380 { 381 return timer_active(t) && !timer_pending(t); 382 } 383 384 static inline bool i915_run_as_guest(void) 385 { 386 #if IS_ENABLED(CONFIG_X86) 387 return !hypervisor_is_type(X86_HYPER_NATIVE); 388 #else 389 /* Not supported yet */ 390 return false; 391 #endif 392 } 393 394 bool i915_vtd_active(struct drm_i915_private *i915); 395 396 #endif /* !__I915_UTILS_H */ 397