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 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG) 49 50 int __i915_inject_probe_error(struct drm_i915_private *i915, int err, 51 const char *func, int line); 52 #define i915_inject_probe_error(_i915, _err) \ 53 __i915_inject_probe_error((_i915), (_err), __func__, __LINE__) 54 bool i915_error_injected(void); 55 56 #else 57 58 #define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; }) 59 #define i915_error_injected() false 60 61 #endif 62 63 #define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV) 64 65 #define i915_probe_error(i915, fmt, ...) ({ \ 66 if (i915_error_injected()) \ 67 drm_dbg(&(i915)->drm, fmt, ##__VA_ARGS__); \ 68 else \ 69 drm_err(&(i915)->drm, fmt, ##__VA_ARGS__); \ 70 }) 71 72 #define range_overflows(start, size, max) ({ \ 73 typeof(start) start__ = (start); \ 74 typeof(size) size__ = (size); \ 75 typeof(max) max__ = (max); \ 76 (void)(&start__ == &size__); \ 77 (void)(&start__ == &max__); \ 78 start__ >= max__ || size__ > max__ - start__; \ 79 }) 80 81 #define range_overflows_t(type, start, size, max) \ 82 range_overflows((type)(start), (type)(size), (type)(max)) 83 84 #define range_overflows_end(start, size, max) ({ \ 85 typeof(start) start__ = (start); \ 86 typeof(size) size__ = (size); \ 87 typeof(max) max__ = (max); \ 88 (void)(&start__ == &size__); \ 89 (void)(&start__ == &max__); \ 90 start__ > max__ || size__ > max__ - start__; \ 91 }) 92 93 #define range_overflows_end_t(type, start, size, max) \ 94 range_overflows_end((type)(start), (type)(size), (type)(max)) 95 96 #define ptr_mask_bits(ptr, n) ({ \ 97 unsigned long __v = (unsigned long)(ptr); \ 98 (typeof(ptr))(__v & -BIT(n)); \ 99 }) 100 101 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 102 103 #define ptr_unpack_bits(ptr, bits, n) ({ \ 104 unsigned long __v = (unsigned long)(ptr); \ 105 *(bits) = __v & (BIT(n) - 1); \ 106 (typeof(ptr))(__v & -BIT(n)); \ 107 }) 108 109 #define ptr_pack_bits(ptr, bits, n) ({ \ 110 unsigned long __bits = (bits); \ 111 GEM_BUG_ON(__bits & -BIT(n)); \ 112 ((typeof(ptr))((unsigned long)(ptr) | __bits)); \ 113 }) 114 115 #define ptr_dec(ptr) ({ \ 116 unsigned long __v = (unsigned long)(ptr); \ 117 (typeof(ptr))(__v - 1); \ 118 }) 119 120 #define ptr_inc(ptr) ({ \ 121 unsigned long __v = (unsigned long)(ptr); \ 122 (typeof(ptr))(__v + 1); \ 123 }) 124 125 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 126 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 127 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 128 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 129 130 #define fetch_and_zero(ptr) ({ \ 131 typeof(*ptr) __T = *(ptr); \ 132 *(ptr) = (typeof(*ptr))0; \ 133 __T; \ 134 }) 135 ptrdiff(const void * a,const void * b)136 static __always_inline ptrdiff_t ptrdiff(const void *a, const void *b) 137 { 138 return a - b; 139 } 140 141 /* 142 * container_of_user: Extract the superclass from a pointer to a member. 143 * 144 * Exactly like container_of() with the exception that it plays nicely 145 * with sparse for __user @ptr. 146 */ 147 #define container_of_user(ptr, type, member) ({ \ 148 void __user *__mptr = (void __user *)(ptr); \ 149 BUILD_BUG_ON_MSG(!__same_type(*(ptr), typeof_member(type, member)) && \ 150 !__same_type(*(ptr), void), \ 151 "pointer type mismatch in container_of()"); \ 152 ((type __user *)(__mptr - offsetof(type, member))); }) 153 154 /* 155 * check_user_mbz: Check that a user value exists and is zero 156 * 157 * Frequently in our uABI we reserve space for future extensions, and 158 * two ensure that userspace is prepared we enforce that space must 159 * be zero. (Then any future extension can safely assume a default value 160 * of 0.) 161 * 162 * check_user_mbz() combines checking that the user pointer is accessible 163 * and that the contained value is zero. 164 * 165 * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success. 166 */ 167 #define check_user_mbz(U) ({ \ 168 typeof(*(U)) mbz__; \ 169 get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0; \ 170 }) 171 172 #define u64_to_ptr(T, x) ({ \ 173 typecheck(u64, x); \ 174 (T *)(uintptr_t)(x); \ 175 }) 176 177 #define __mask_next_bit(mask) ({ \ 178 int __idx = ffs(mask) - 1; \ 179 mask &= ~BIT(__idx); \ 180 __idx; \ 181 }) 182 is_power_of_2_u64(u64 n)183 static inline bool is_power_of_2_u64(u64 n) 184 { 185 return (n != 0 && ((n & (n - 1)) == 0)); 186 } 187 __list_del_many(struct list_head * head,struct list_head * first)188 static inline void __list_del_many(struct list_head *head, 189 struct list_head *first) 190 { 191 first->prev = head; 192 WRITE_ONCE(head->next, first); 193 } 194 list_is_last_rcu(const struct list_head * list,const struct list_head * head)195 static inline int list_is_last_rcu(const struct list_head *list, 196 const struct list_head *head) 197 { 198 return READ_ONCE(list->next) == head; 199 } 200 msecs_to_jiffies_timeout(const unsigned int m)201 static inline unsigned long msecs_to_jiffies_timeout(const unsigned int m) 202 { 203 unsigned long j = msecs_to_jiffies(m); 204 205 return min_t(unsigned long, MAX_JIFFY_OFFSET, j + 1); 206 } 207 208 /* 209 * If you need to wait X milliseconds between events A and B, but event B 210 * doesn't happen exactly after event A, you record the timestamp (jiffies) of 211 * when event A happened, then just before event B you call this function and 212 * pass the timestamp as the first argument, and X as the second argument. 213 */ 214 static inline void wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies,int to_wait_ms)215 wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) 216 { 217 unsigned long target_jiffies, tmp_jiffies, remaining_jiffies; 218 219 /* 220 * Don't re-read the value of "jiffies" every time since it may change 221 * behind our back and break the math. 222 */ 223 tmp_jiffies = jiffies; 224 target_jiffies = timestamp_jiffies + 225 msecs_to_jiffies_timeout(to_wait_ms); 226 227 if (time_after(target_jiffies, tmp_jiffies)) { 228 remaining_jiffies = target_jiffies - tmp_jiffies; 229 while (remaining_jiffies) 230 remaining_jiffies = 231 schedule_timeout_uninterruptible(remaining_jiffies); 232 } 233 } 234 235 /* 236 * __wait_for - magic wait macro 237 * 238 * Macro to help avoid open coding check/wait/timeout patterns. Note that it's 239 * important that we check the condition again after having timed out, since the 240 * timeout could be due to preemption or similar and we've never had a chance to 241 * check the condition before the timeout. 242 */ 243 #define __wait_for(OP, COND, US, Wmin, Wmax) ({ \ 244 const ktime_t end__ = ktime_add_ns(ktime_get_raw(), 1000ll * (US)); \ 245 long wait__ = (Wmin); /* recommended min for usleep is 10 us */ \ 246 int ret__; \ 247 might_sleep(); \ 248 for (;;) { \ 249 const bool expired__ = ktime_after(ktime_get_raw(), end__); \ 250 OP; \ 251 /* Guarantee COND check prior to timeout */ \ 252 barrier(); \ 253 if (COND) { \ 254 ret__ = 0; \ 255 break; \ 256 } \ 257 if (expired__) { \ 258 ret__ = -ETIMEDOUT; \ 259 break; \ 260 } \ 261 usleep_range(wait__, wait__ * 2); \ 262 if (wait__ < (Wmax)) \ 263 wait__ <<= 1; \ 264 } \ 265 ret__; \ 266 }) 267 268 #define _wait_for(COND, US, Wmin, Wmax) __wait_for(, (COND), (US), (Wmin), \ 269 (Wmax)) 270 #define wait_for(COND, MS) _wait_for((COND), (MS) * 1000, 10, 1000) 271 272 /* If CONFIG_PREEMPT_COUNT is disabled, in_atomic() always reports false. */ 273 #if defined(CONFIG_DRM_I915_DEBUG) && defined(CONFIG_PREEMPT_COUNT) 274 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) WARN_ON_ONCE((ATOMIC) && !in_atomic()) 275 #else 276 # define _WAIT_FOR_ATOMIC_CHECK(ATOMIC) do { } while (0) 277 #endif 278 279 #define _wait_for_atomic(COND, US, ATOMIC) \ 280 ({ \ 281 int cpu, ret, timeout = (US) * 1000; \ 282 u64 base; \ 283 _WAIT_FOR_ATOMIC_CHECK(ATOMIC); \ 284 if (!(ATOMIC)) { \ 285 preempt_disable(); \ 286 cpu = smp_processor_id(); \ 287 } \ 288 base = local_clock(); \ 289 for (;;) { \ 290 u64 now = local_clock(); \ 291 if (!(ATOMIC)) \ 292 preempt_enable(); \ 293 /* Guarantee COND check prior to timeout */ \ 294 barrier(); \ 295 if (COND) { \ 296 ret = 0; \ 297 break; \ 298 } \ 299 if (now - base >= timeout) { \ 300 ret = -ETIMEDOUT; \ 301 break; \ 302 } \ 303 cpu_relax(); \ 304 if (!(ATOMIC)) { \ 305 preempt_disable(); \ 306 if (unlikely(cpu != smp_processor_id())) { \ 307 timeout -= now - base; \ 308 cpu = smp_processor_id(); \ 309 base = local_clock(); \ 310 } \ 311 } \ 312 } \ 313 ret; \ 314 }) 315 316 #define wait_for_us(COND, US) \ 317 ({ \ 318 int ret__; \ 319 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 320 if ((US) > 10) \ 321 ret__ = _wait_for((COND), (US), 10, 10); \ 322 else \ 323 ret__ = _wait_for_atomic((COND), (US), 0); \ 324 ret__; \ 325 }) 326 327 #define wait_for_atomic_us(COND, US) \ 328 ({ \ 329 BUILD_BUG_ON(!__builtin_constant_p(US)); \ 330 BUILD_BUG_ON((US) > 50000); \ 331 _wait_for_atomic((COND), (US), 1); \ 332 }) 333 334 #define wait_for_atomic(COND, MS) wait_for_atomic_us((COND), (MS) * 1000) 335 336 #define KHz(x) (1000 * (x)) 337 #define MHz(x) KHz(1000 * (x)) 338 339 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint); __add_taint_for_CI(unsigned int taint)340 static inline void __add_taint_for_CI(unsigned int taint) 341 { 342 /* 343 * The system is "ok", just about surviving for the user, but 344 * CI results are now unreliable as the HW is very suspect. 345 * CI checks the taint state after every test and will reboot 346 * the machine if the kernel is tainted. 347 */ 348 add_taint(taint, LOCKDEP_STILL_OK); 349 } 350 351 void cancel_timer(struct timer_list *t); 352 void set_timer_ms(struct timer_list *t, unsigned long timeout); 353 timer_active(const struct timer_list * t)354 static inline bool timer_active(const struct timer_list *t) 355 { 356 return READ_ONCE(t->expires); 357 } 358 timer_expired(const struct timer_list * t)359 static inline bool timer_expired(const struct timer_list *t) 360 { 361 return timer_active(t) && !timer_pending(t); 362 } 363 i915_run_as_guest(void)364 static inline bool i915_run_as_guest(void) 365 { 366 #if IS_ENABLED(CONFIG_X86) 367 return !hypervisor_is_type(X86_HYPER_NATIVE); 368 #else 369 /* Not supported yet */ 370 return false; 371 #endif 372 } 373 374 bool i915_vtd_active(struct drm_i915_private *i915); 375 376 bool i915_direct_stolen_access(struct drm_i915_private *i915); 377 378 #endif /* !__I915_UTILS_H */ 379