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 #undef WARN_ON 29 /* Many gcc seem to no see through this and fall over :( */ 30 #if 0 31 #define WARN_ON(x) ({ \ 32 bool __i915_warn_cond = (x); \ 33 if (__builtin_constant_p(__i915_warn_cond)) \ 34 BUILD_BUG_ON(__i915_warn_cond); \ 35 WARN(__i915_warn_cond, "WARN_ON(" #x ")"); }) 36 #else 37 #define WARN_ON(x) WARN((x), "%s", "WARN_ON(" __stringify(x) ")") 38 #endif 39 40 #undef WARN_ON_ONCE 41 #define WARN_ON_ONCE(x) WARN_ONCE((x), "%s", "WARN_ON_ONCE(" __stringify(x) ")") 42 43 #define MISSING_CASE(x) WARN(1, "Missing switch case (%lu) in %s\n", \ 44 (long)(x), __func__) 45 46 #if GCC_VERSION >= 70000 47 #define add_overflows(A, B) \ 48 __builtin_add_overflow_p((A), (B), (typeof((A) + (B)))0) 49 #else 50 #define add_overflows(A, B) ({ \ 51 typeof(A) a = (A); \ 52 typeof(B) b = (B); \ 53 a + b < a; \ 54 }) 55 #endif 56 57 #define range_overflows(start, size, max) ({ \ 58 typeof(start) start__ = (start); \ 59 typeof(size) size__ = (size); \ 60 typeof(max) max__ = (max); \ 61 (void)(&start__ == &size__); \ 62 (void)(&start__ == &max__); \ 63 start__ > max__ || size__ > max__ - start__; \ 64 }) 65 66 #define range_overflows_t(type, start, size, max) \ 67 range_overflows((type)(start), (type)(size), (type)(max)) 68 69 /* Note we don't consider signbits :| */ 70 #define overflows_type(x, T) \ 71 (sizeof(x) > sizeof(T) && (x) >> (sizeof(T) * BITS_PER_BYTE)) 72 73 #define ptr_mask_bits(ptr, n) ({ \ 74 unsigned long __v = (unsigned long)(ptr); \ 75 (typeof(ptr))(__v & -BIT(n)); \ 76 }) 77 78 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1)) 79 80 #define ptr_unpack_bits(ptr, bits, n) ({ \ 81 unsigned long __v = (unsigned long)(ptr); \ 82 *(bits) = __v & (BIT(n) - 1); \ 83 (typeof(ptr))(__v & -BIT(n)); \ 84 }) 85 86 #define ptr_pack_bits(ptr, bits, n) \ 87 ((typeof(ptr))((unsigned long)(ptr) | (bits))) 88 89 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT) 90 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT) 91 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT) 92 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT) 93 94 #define ptr_offset(ptr, member) offsetof(typeof(*(ptr)), member) 95 96 #define fetch_and_zero(ptr) ({ \ 97 typeof(*ptr) __T = *(ptr); \ 98 *(ptr) = (typeof(*ptr))0; \ 99 __T; \ 100 }) 101 102 #define u64_to_ptr(T, x) ({ \ 103 typecheck(u64, x); \ 104 (T *)(uintptr_t)(x); \ 105 }) 106 107 #define __mask_next_bit(mask) ({ \ 108 int __idx = ffs(mask) - 1; \ 109 mask &= ~BIT(__idx); \ 110 __idx; \ 111 }) 112 113 #include <linux/list.h> 114 115 static inline void __list_del_many(struct list_head *head, 116 struct list_head *first) 117 { 118 first->prev = head; 119 WRITE_ONCE(head->next, first); 120 } 121 122 #endif /* !__I915_UTILS_H */ 123