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 #define ptr_mask_bits(ptr, n) ({ \ 119 unsigned long __v = (unsigned long)(ptr); \ 120 (typeof(ptr))(__v & -BIT(n)); \ 121 }) 122 123 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 124 125 #define ptr_unpack_bits(ptr, bits, n) ({ \ 126 unsigned long __v = (unsigned long)(ptr); \ 127 *(bits) = __v & (BIT(n) - 1); \ 128 (typeof(ptr))(__v & -BIT(n)); \ 129 }) 130 131 #define ptr_pack_bits(ptr, bits, n) ({ \ 132 unsigned long __bits = (bits); \ 133 GEM_BUG_ON(__bits & -BIT(n)); \ 134 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \ 135 }) 136 137 #define ptr_dec(ptr) ({ \ 138 unsigned long __v = (unsigned long)(ptr); \ 139 (typeof(ptr))(__v - 1); \ 140 }) 141 142 #define ptr_inc(ptr) ({ \ 143 unsigned long __v = (unsigned long)(ptr); \ 144 (typeof(ptr))(__v + 1); \ 145 }) 146 147 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 148 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 149 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 150 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 151 152 #define struct_member(T, member) (((T *)0)->member) 153 154 #define fetch_and_zero(ptr) ({ \ 155 typeof(*ptr) __T = *(ptr); \ 156 *(ptr) = (typeof(*ptr))0; \ 157 __T; \ 158 }) 159 160 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b) 161 { 162 return a - b; 163 } 164 165 /* 166 * container_of_user: Extract the superclass from a pointer to a member. 167 * 168 * Exactly like container_of() with the exception that it plays nicely 169 * with sparse for __user @ptr. 170 */ 171 #define container_of_user(ptr, type, member) ({ \ 172 void __user *__mptr = (void __user *)(ptr); \ 173 BUILD_BUG_ON_MSG(!__same_type(*(ptr), struct_member(type, member)) && \ 174 !__same_type(*(ptr), void), \ 175 "pointer type mismatch in container_of()"); \ 176 ((type __user *)(__mptr - offsetof(type, member))); }) 177 178 /* 179 * check_user_mbz: Check that a user value exists and is zero 180 * 181 * Frequently in our uABI we reserve space for future extensions, and 182 * two ensure that userspace is prepared we enforce that space must 183 * be zero. (Then any future extension can safely assume a default value 184 * of 0.) 185 * 186 * check_user_mbz() combines checking that the user pointer is accessible 187 * and that the contained value is zero. 188 * 189 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 190 */ 191 #define check_user_mbz(U) ({ \ 192 typeof(*(U)) mbz__; \ 193 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 194 }) 195 196 #define u64_to_ptr(T, x) ({ \ 197 typecheck(u64, x); \ 198 (T *)(uintptr_t)(x); \ 199 }) 200 201 #define __mask_next_bit(mask) ({ \ 202 int __idx = ffs(mask) - 1; \ 203 mask &= ~BIT(__idx); \ 204 __idx; \ 205 }) 206 207 static inline bool is_power_of_2_u64(u64 n) 208 { 209 return (n != 0 && ((n & (n - 1)) == 0)); 210 } 211 212 static inline void __list_del_many(struct list_head *head, 213 struct list_head *first) 214 { 215 first->prev = head; 216 WRITE_ONCE(head->next, first); 217 } 218 219 static inline int list_is_last_rcu(const struct list_head *list, 220 const struct list_head *head) 221 { 222 return READ_ONCE(list->next) == head; 223 } 224 225 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 226 { 227 unsigned long j = msecs_to_jiffies(m); 228 229 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 230 } 231 232 /* 233 * If you need to wait X milliseconds between events A and B, but event B 234 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 235 * when event A happened, then just before event B you call this function and 236 * pass the timestamp as the first argument, and X as the second argument. 237 */ 238 static inline void 239 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 240 { 241 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 242 243 /* 244 * Don't re-read the value of "jiffies" every time since it may change 245 * behind our back and break the math. 246 */ 247 tmp_jiffies = jiffies; 248 target_jiffies = timestamp_jiffies + 249 msecs_to_jiffies_timeout(to_wait_ms); 250 251 if (time_after(target_jiffies, tmp_jiffies)) { 252 remaining_jiffies = target_jiffies - tmp_jiffies; 253 while (remaining_jiffies) 254 remaining_jiffies = 255 schedule_timeout_uninterruptible(remaining_jiffies); 256 } 257 } 258 259 /** 260 * __wait_for - magic wait macro 261 * 262 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 263 * important that we check the condition again after having timed out, since the 264 * timeout could be due to preemption or similar and we've never had a chance to 265 * check the condition before the timeout. 266 */ 267 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 268 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 269 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 270 int ret__; \ 271 might_sleep(); \ 272 for (;;) { \ 273 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 274 OP; \ 275 /* Guarantee COND check prior to timeout */ \ 276 barrier(); \ 277 if (COND) { \ 278 ret__ = 0; \ 279 break; \ 280 } \ 281 if (expired__) { \ 282 ret__ = -ETIMEDOUT; \ 283 break; \ 284 } \ 285 usleep_range(wait__, wait__ * 2); \ 286 if (wait__ < (Wmax)) \ 287 wait__ <<= 1; \ 288 } \ 289 ret__; \ 290 }) 291 292 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 293 (Wmax)) 294 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 295 296 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 297 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 298 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 299 #else 300 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 301 #endif 302 303 #define _wait_for_atomic(COND, US, ATOMIC) \ 304 ({ \ 305 int cpu, ret, timeout = (US) * 1000; \ 306 u64 base; \ 307 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 308 if (!(ATOMIC)) { \ 309 preempt_disable(); \ 310 cpu = smp_processor_id(); \ 311 } \ 312 base = local_clock(); \ 313 for (;;) { \ 314 u64 now = local_clock(); \ 315 if (!(ATOMIC)) \ 316 preempt_enable(); \ 317 /* Guarantee COND check prior to timeout */ \ 318 barrier(); \ 319 if (COND) { \ 320 ret = 0; \ 321 break; \ 322 } \ 323 if (now - base >= timeout) { \ 324 ret = -ETIMEDOUT; \ 325 break; \ 326 } \ 327 cpu_relax(); \ 328 if (!(ATOMIC)) { \ 329 preempt_disable(); \ 330 if (unlikely(cpu != smp_processor_id())) { \ 331 timeout -= now - base; \ 332 cpu = smp_processor_id(); \ 333 base = local_clock(); \ 334 } \ 335 } \ 336 } \ 337 ret; \ 338 }) 339 340 #define wait_for_us(COND, US) \ 341 ({ \ 342 int ret__; \ 343 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 344 if ((US) > 10) \ 345 ret__ = _wait_for((COND), (US), 10, 10); \ 346 else \ 347 ret__ = _wait_for_atomic((COND), (US), 0); \ 348 ret__; \ 349 }) 350 351 #define wait_for_atomic_us(COND, US) \ 352 ({ \ 353 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 354 BUILD_BUG_ON((US) > 50000); \ 355 _wait_for_atomic((COND), (US), 1); \ 356 }) 357 358 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 359 360 #define KHz(x) (1000 * (x)) 361 #define MHz(x) KHz(1000 * (x)) 362 363 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint); 364 static inline void __add_taint_for_CI(unsigned int taint) 365 { 366 /* 367 * The system is "ok", just about surviving for the user, but 368 * CI results are now unreliable as the HW is very suspect. 369 * CI checks the taint state after every test and will reboot 370 * the machine if the kernel is tainted. 371 */ 372 add_taint(taint, LOCKDEP_STILL_OK); 373 } 374 375 void cancel_timer(struct timer_list *t); 376 void set_timer_ms(struct timer_list *t, unsigned long timeout); 377 378 static inline bool timer_active(const struct timer_list *t) 379 { 380 return READ_ONCE(t->expires); 381 } 382 383 static inline bool timer_expired(const struct timer_list *t) 384 { 385 return timer_active(t) && !timer_pending(t); 386 } 387 388 static inline bool i915_run_as_guest(void) 389 { 390 #if IS_ENABLED(CONFIG_X86) 391 return !hypervisor_is_type(X86_HYPER_NATIVE); 392 #else 393 /* Not supported yet */ 394 return false; 395 #endif 396 } 397 398 bool i915_vtd_active(struct drm_i915_private *i915); 399 400 #endif /* !__I915_UTILS_H */ 401