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1408 | serge | 1 | #ifndef _LINUX_LIST_H |
2 | #define _LINUX_LIST_H |
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3 | |||
1964 | serge | 4 | #include |
1408 | serge | 5 | #include |
1964 | serge | 6 | #include |
5270 | serge | 7 | #include |
8 | #include |
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1408 | serge | 9 | |
10 | /* |
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11 | * Simple doubly linked list implementation. |
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12 | * |
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13 | * Some of the internal functions ("__xxx") are useful when |
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14 | * manipulating whole lists rather than single entries, as |
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15 | * sometimes we already know the next/prev entries and we can |
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16 | * generate better code by using them directly rather than |
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17 | * using the generic single-entry routines. |
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18 | */ |
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19 | |||
20 | #define LIST_HEAD_INIT(name) { &(name), &(name) } |
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21 | |||
22 | #define LIST_HEAD(name) \ |
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23 | struct list_head name = LIST_HEAD_INIT(name) |
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24 | |||
25 | static inline void INIT_LIST_HEAD(struct list_head *list) |
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26 | { |
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27 | list->next = list; |
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28 | list->prev = list; |
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29 | } |
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30 | |||
31 | /* |
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32 | * Insert a new entry between two known consecutive entries. |
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33 | * |
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34 | * This is only for internal list manipulation where we know |
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35 | * the prev/next entries already! |
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36 | */ |
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37 | #ifndef CONFIG_DEBUG_LIST |
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38 | static inline void __list_add(struct list_head *new, |
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39 | struct list_head *prev, |
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40 | struct list_head *next) |
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41 | { |
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42 | next->prev = new; |
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43 | new->next = next; |
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44 | new->prev = prev; |
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45 | prev->next = new; |
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46 | } |
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47 | #else |
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48 | extern void __list_add(struct list_head *new, |
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49 | struct list_head *prev, |
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50 | struct list_head *next); |
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51 | #endif |
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52 | |||
53 | /** |
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54 | * list_add - add a new entry |
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55 | * @new: new entry to be added |
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56 | * @head: list head to add it after |
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57 | * |
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58 | * Insert a new entry after the specified head. |
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59 | * This is good for implementing stacks. |
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60 | */ |
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61 | static inline void list_add(struct list_head *new, struct list_head *head) |
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62 | { |
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63 | __list_add(new, head, head->next); |
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64 | } |
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65 | |||
66 | |||
67 | /** |
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68 | * list_add_tail - add a new entry |
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69 | * @new: new entry to be added |
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70 | * @head: list head to add it before |
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71 | * |
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72 | * Insert a new entry before the specified head. |
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73 | * This is useful for implementing queues. |
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74 | */ |
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75 | static inline void list_add_tail(struct list_head *new, struct list_head *head) |
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76 | { |
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77 | __list_add(new, head->prev, head); |
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78 | } |
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79 | |||
80 | /* |
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81 | * Delete a list entry by making the prev/next entries |
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82 | * point to each other. |
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83 | * |
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84 | * This is only for internal list manipulation where we know |
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85 | * the prev/next entries already! |
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86 | */ |
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87 | static inline void __list_del(struct list_head * prev, struct list_head * next) |
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88 | { |
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89 | next->prev = prev; |
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6934 | serge | 90 | WRITE_ONCE(prev->next, next); |
1408 | serge | 91 | } |
92 | |||
93 | /** |
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94 | * list_del - deletes entry from list. |
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95 | * @entry: the element to delete from the list. |
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96 | * Note: list_empty() on entry does not return true after this, the entry is |
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97 | * in an undefined state. |
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98 | */ |
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99 | #ifndef CONFIG_DEBUG_LIST |
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1970 | serge | 100 | static inline void __list_del_entry(struct list_head *entry) |
101 | { |
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102 | __list_del(entry->prev, entry->next); |
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103 | } |
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104 | |||
1408 | serge | 105 | static inline void list_del(struct list_head *entry) |
106 | { |
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107 | __list_del(entry->prev, entry->next); |
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108 | entry->next = LIST_POISON1; |
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109 | entry->prev = LIST_POISON2; |
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110 | } |
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111 | #else |
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1970 | serge | 112 | extern void __list_del_entry(struct list_head *entry); |
1408 | serge | 113 | extern void list_del(struct list_head *entry); |
114 | #endif |
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115 | |||
116 | /** |
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117 | * list_replace - replace old entry by new one |
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118 | * @old : the element to be replaced |
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119 | * @new : the new element to insert |
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120 | * |
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121 | * If @old was empty, it will be overwritten. |
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122 | */ |
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123 | static inline void list_replace(struct list_head *old, |
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124 | struct list_head *new) |
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125 | { |
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126 | new->next = old->next; |
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127 | new->next->prev = new; |
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128 | new->prev = old->prev; |
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129 | new->prev->next = new; |
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130 | } |
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131 | |||
132 | static inline void list_replace_init(struct list_head *old, |
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133 | struct list_head *new) |
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134 | { |
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135 | list_replace(old, new); |
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136 | INIT_LIST_HEAD(old); |
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137 | } |
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138 | |||
139 | /** |
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140 | * list_del_init - deletes entry from list and reinitialize it. |
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141 | * @entry: the element to delete from the list. |
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142 | */ |
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143 | static inline void list_del_init(struct list_head *entry) |
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144 | { |
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1970 | serge | 145 | __list_del_entry(entry); |
1408 | serge | 146 | INIT_LIST_HEAD(entry); |
147 | } |
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148 | |||
149 | /** |
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150 | * list_move - delete from one list and add as another's head |
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151 | * @list: the entry to move |
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152 | * @head: the head that will precede our entry |
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153 | */ |
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154 | static inline void list_move(struct list_head *list, struct list_head *head) |
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155 | { |
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1970 | serge | 156 | __list_del_entry(list); |
1408 | serge | 157 | list_add(list, head); |
158 | } |
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159 | |||
160 | /** |
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161 | * list_move_tail - delete from one list and add as another's tail |
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162 | * @list: the entry to move |
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163 | * @head: the head that will follow our entry |
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164 | */ |
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165 | static inline void list_move_tail(struct list_head *list, |
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166 | struct list_head *head) |
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167 | { |
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1970 | serge | 168 | __list_del_entry(list); |
1408 | serge | 169 | list_add_tail(list, head); |
170 | } |
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171 | |||
172 | /** |
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173 | * list_is_last - tests whether @list is the last entry in list @head |
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174 | * @list: the entry to test |
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175 | * @head: the head of the list |
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176 | */ |
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177 | static inline int list_is_last(const struct list_head *list, |
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178 | const struct list_head *head) |
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179 | { |
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180 | return list->next == head; |
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181 | } |
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182 | |||
183 | /** |
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184 | * list_empty - tests whether a list is empty |
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185 | * @head: the list to test. |
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186 | */ |
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187 | static inline int list_empty(const struct list_head *head) |
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188 | { |
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189 | return head->next == head; |
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190 | } |
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191 | |||
192 | /** |
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193 | * list_empty_careful - tests whether a list is empty and not being modified |
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194 | * @head: the list to test |
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195 | * |
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196 | * Description: |
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197 | * tests whether a list is empty _and_ checks that no other CPU might be |
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198 | * in the process of modifying either member (next or prev) |
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199 | * |
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200 | * NOTE: using list_empty_careful() without synchronization |
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201 | * can only be safe if the only activity that can happen |
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202 | * to the list entry is list_del_init(). Eg. it cannot be used |
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203 | * if another CPU could re-list_add() it. |
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204 | */ |
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205 | static inline int list_empty_careful(const struct list_head *head) |
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206 | { |
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6082 | serge | 207 | struct list_head *next = head->next; |
1408 | serge | 208 | return (next == head) && (next == head->prev); |
209 | } |
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210 | |||
211 | /** |
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1964 | serge | 212 | * list_rotate_left - rotate the list to the left |
213 | * @head: the head of the list |
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214 | */ |
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215 | static inline void list_rotate_left(struct list_head *head) |
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216 | { |
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217 | struct list_head *first; |
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218 | |||
219 | if (!list_empty(head)) { |
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220 | first = head->next; |
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221 | list_move_tail(first, head); |
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222 | } |
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223 | } |
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224 | |||
225 | /** |
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1408 | serge | 226 | * list_is_singular - tests whether a list has just one entry. |
227 | * @head: the list to test. |
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228 | */ |
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229 | static inline int list_is_singular(const struct list_head *head) |
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230 | { |
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231 | return !list_empty(head) && (head->next == head->prev); |
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232 | } |
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233 | |||
234 | static inline void __list_cut_position(struct list_head *list, |
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235 | struct list_head *head, struct list_head *entry) |
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236 | { |
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237 | struct list_head *new_first = entry->next; |
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238 | list->next = head->next; |
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239 | list->next->prev = list; |
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240 | list->prev = entry; |
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241 | entry->next = list; |
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242 | head->next = new_first; |
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243 | new_first->prev = head; |
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244 | } |
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245 | |||
246 | /** |
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247 | * list_cut_position - cut a list into two |
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248 | * @list: a new list to add all removed entries |
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249 | * @head: a list with entries |
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250 | * @entry: an entry within head, could be the head itself |
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251 | * and if so we won't cut the list |
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252 | * |
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253 | * This helper moves the initial part of @head, up to and |
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254 | * including @entry, from @head to @list. You should |
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255 | * pass on @entry an element you know is on @head. @list |
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256 | * should be an empty list or a list you do not care about |
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257 | * losing its data. |
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258 | * |
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259 | */ |
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260 | static inline void list_cut_position(struct list_head *list, |
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261 | struct list_head *head, struct list_head *entry) |
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262 | { |
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263 | if (list_empty(head)) |
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264 | return; |
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265 | if (list_is_singular(head) && |
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266 | (head->next != entry && head != entry)) |
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267 | return; |
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268 | if (entry == head) |
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269 | INIT_LIST_HEAD(list); |
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270 | else |
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271 | __list_cut_position(list, head, entry); |
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272 | } |
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273 | |||
274 | static inline void __list_splice(const struct list_head *list, |
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275 | struct list_head *prev, |
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276 | struct list_head *next) |
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277 | { |
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278 | struct list_head *first = list->next; |
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279 | struct list_head *last = list->prev; |
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280 | |||
281 | first->prev = prev; |
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282 | prev->next = first; |
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283 | |||
284 | last->next = next; |
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285 | next->prev = last; |
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286 | } |
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287 | |||
288 | /** |
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289 | * list_splice - join two lists, this is designed for stacks |
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290 | * @list: the new list to add. |
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291 | * @head: the place to add it in the first list. |
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292 | */ |
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293 | static inline void list_splice(const struct list_head *list, |
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294 | struct list_head *head) |
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295 | { |
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296 | if (!list_empty(list)) |
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297 | __list_splice(list, head, head->next); |
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298 | } |
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299 | |||
300 | /** |
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301 | * list_splice_tail - join two lists, each list being a queue |
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302 | * @list: the new list to add. |
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303 | * @head: the place to add it in the first list. |
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304 | */ |
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305 | static inline void list_splice_tail(struct list_head *list, |
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306 | struct list_head *head) |
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307 | { |
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308 | if (!list_empty(list)) |
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309 | __list_splice(list, head->prev, head); |
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310 | } |
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311 | |||
312 | /** |
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313 | * list_splice_init - join two lists and reinitialise the emptied list. |
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314 | * @list: the new list to add. |
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315 | * @head: the place to add it in the first list. |
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316 | * |
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317 | * The list at @list is reinitialised |
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318 | */ |
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319 | static inline void list_splice_init(struct list_head *list, |
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320 | struct list_head *head) |
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321 | { |
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322 | if (!list_empty(list)) { |
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323 | __list_splice(list, head, head->next); |
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324 | INIT_LIST_HEAD(list); |
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325 | } |
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326 | } |
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327 | |||
328 | /** |
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329 | * list_splice_tail_init - join two lists and reinitialise the emptied list |
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330 | * @list: the new list to add. |
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331 | * @head: the place to add it in the first list. |
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332 | * |
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333 | * Each of the lists is a queue. |
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334 | * The list at @list is reinitialised |
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335 | */ |
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336 | static inline void list_splice_tail_init(struct list_head *list, |
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337 | struct list_head *head) |
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338 | { |
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339 | if (!list_empty(list)) { |
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340 | __list_splice(list, head->prev, head); |
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341 | INIT_LIST_HEAD(list); |
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342 | } |
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343 | } |
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344 | |||
345 | /** |
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346 | * list_entry - get the struct for this entry |
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347 | * @ptr: the &struct list_head pointer. |
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348 | * @type: the type of the struct this is embedded in. |
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5270 | serge | 349 | * @member: the name of the list_head within the struct. |
1408 | serge | 350 | */ |
351 | #define list_entry(ptr, type, member) \ |
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352 | container_of(ptr, type, member) |
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353 | |||
354 | /** |
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355 | * list_first_entry - get the first element from a list |
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356 | * @ptr: the list head to take the element from. |
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357 | * @type: the type of the struct this is embedded in. |
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5270 | serge | 358 | * @member: the name of the list_head within the struct. |
1408 | serge | 359 | * |
360 | * Note, that list is expected to be not empty. |
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361 | */ |
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362 | #define list_first_entry(ptr, type, member) \ |
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363 | list_entry((ptr)->next, type, member) |
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364 | |||
365 | /** |
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5056 | serge | 366 | * list_last_entry - get the last element from a list |
367 | * @ptr: the list head to take the element from. |
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368 | * @type: the type of the struct this is embedded in. |
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5270 | serge | 369 | * @member: the name of the list_head within the struct. |
5056 | serge | 370 | * |
371 | * Note, that list is expected to be not empty. |
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372 | */ |
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373 | #define list_last_entry(ptr, type, member) \ |
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374 | list_entry((ptr)->prev, type, member) |
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375 | |||
376 | /** |
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4065 | Serge | 377 | * list_first_entry_or_null - get the first element from a list |
378 | * @ptr: the list head to take the element from. |
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379 | * @type: the type of the struct this is embedded in. |
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5270 | serge | 380 | * @member: the name of the list_head within the struct. |
4065 | Serge | 381 | * |
382 | * Note that if the list is empty, it returns NULL. |
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1408 | serge | 383 | */ |
4065 | Serge | 384 | #define list_first_entry_or_null(ptr, type, member) \ |
385 | (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) |
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1408 | serge | 386 | |
387 | /** |
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5056 | serge | 388 | * list_next_entry - get the next element in list |
389 | * @pos: the type * to cursor |
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5270 | serge | 390 | * @member: the name of the list_head within the struct. |
5056 | serge | 391 | */ |
392 | #define list_next_entry(pos, member) \ |
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393 | list_entry((pos)->member.next, typeof(*(pos)), member) |
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394 | |||
395 | /** |
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396 | * list_prev_entry - get the prev element in list |
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397 | * @pos: the type * to cursor |
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5270 | serge | 398 | * @member: the name of the list_head within the struct. |
5056 | serge | 399 | */ |
400 | #define list_prev_entry(pos, member) \ |
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401 | list_entry((pos)->member.prev, typeof(*(pos)), member) |
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402 | |||
403 | /** |
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4065 | Serge | 404 | * list_for_each - iterate over a list |
1408 | serge | 405 | * @pos: the &struct list_head to use as a loop cursor. |
406 | * @head: the head for your list. |
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407 | */ |
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4065 | Serge | 408 | #define list_for_each(pos, head) \ |
1408 | serge | 409 | for (pos = (head)->next; pos != (head); pos = pos->next) |
410 | |||
411 | /** |
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412 | * list_for_each_prev - iterate over a list backwards |
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413 | * @pos: the &struct list_head to use as a loop cursor. |
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414 | * @head: the head for your list. |
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415 | */ |
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416 | #define list_for_each_prev(pos, head) \ |
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1970 | serge | 417 | for (pos = (head)->prev; pos != (head); pos = pos->prev) |
1408 | serge | 418 | |
419 | /** |
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420 | * list_for_each_safe - iterate over a list safe against removal of list entry |
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421 | * @pos: the &struct list_head to use as a loop cursor. |
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422 | * @n: another &struct list_head to use as temporary storage |
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423 | * @head: the head for your list. |
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424 | */ |
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425 | #define list_for_each_safe(pos, n, head) \ |
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426 | for (pos = (head)->next, n = pos->next; pos != (head); \ |
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427 | pos = n, n = pos->next) |
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428 | |||
429 | /** |
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430 | * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry |
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431 | * @pos: the &struct list_head to use as a loop cursor. |
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432 | * @n: another &struct list_head to use as temporary storage |
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433 | * @head: the head for your list. |
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434 | */ |
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435 | #define list_for_each_prev_safe(pos, n, head) \ |
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436 | for (pos = (head)->prev, n = pos->prev; \ |
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1970 | serge | 437 | pos != (head); \ |
1408 | serge | 438 | pos = n, n = pos->prev) |
439 | |||
440 | /** |
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441 | * list_for_each_entry - iterate over list of given type |
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442 | * @pos: the type * to use as a loop cursor. |
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443 | * @head: the head for your list. |
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5270 | serge | 444 | * @member: the name of the list_head within the struct. |
1408 | serge | 445 | */ |
446 | #define list_for_each_entry(pos, head, member) \ |
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5056 | serge | 447 | for (pos = list_first_entry(head, typeof(*pos), member); \ |
6082 | serge | 448 | &pos->member != (head); \ |
5056 | serge | 449 | pos = list_next_entry(pos, member)) |
1408 | serge | 450 | |
451 | /** |
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452 | * list_for_each_entry_reverse - iterate backwards over list of given type. |
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453 | * @pos: the type * to use as a loop cursor. |
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454 | * @head: the head for your list. |
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5270 | serge | 455 | * @member: the name of the list_head within the struct. |
1408 | serge | 456 | */ |
457 | #define list_for_each_entry_reverse(pos, head, member) \ |
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5056 | serge | 458 | for (pos = list_last_entry(head, typeof(*pos), member); \ |
6082 | serge | 459 | &pos->member != (head); \ |
5056 | serge | 460 | pos = list_prev_entry(pos, member)) |
1408 | serge | 461 | |
462 | /** |
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463 | * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() |
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464 | * @pos: the type * to use as a start point |
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465 | * @head: the head of the list |
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5270 | serge | 466 | * @member: the name of the list_head within the struct. |
1408 | serge | 467 | * |
468 | * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). |
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469 | */ |
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470 | #define list_prepare_entry(pos, head, member) \ |
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471 | ((pos) ? : list_entry(head, typeof(*pos), member)) |
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472 | |||
473 | /** |
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474 | * list_for_each_entry_continue - continue iteration over list of given type |
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475 | * @pos: the type * to use as a loop cursor. |
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476 | * @head: the head for your list. |
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5270 | serge | 477 | * @member: the name of the list_head within the struct. |
1408 | serge | 478 | * |
479 | * Continue to iterate over list of given type, continuing after |
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480 | * the current position. |
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481 | */ |
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482 | #define list_for_each_entry_continue(pos, head, member) \ |
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5056 | serge | 483 | for (pos = list_next_entry(pos, member); \ |
6082 | serge | 484 | &pos->member != (head); \ |
5056 | serge | 485 | pos = list_next_entry(pos, member)) |
1408 | serge | 486 | |
487 | /** |
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488 | * list_for_each_entry_continue_reverse - iterate backwards from the given point |
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489 | * @pos: the type * to use as a loop cursor. |
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490 | * @head: the head for your list. |
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5270 | serge | 491 | * @member: the name of the list_head within the struct. |
1408 | serge | 492 | * |
493 | * Start to iterate over list of given type backwards, continuing after |
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494 | * the current position. |
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495 | */ |
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496 | #define list_for_each_entry_continue_reverse(pos, head, member) \ |
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5056 | serge | 497 | for (pos = list_prev_entry(pos, member); \ |
6082 | serge | 498 | &pos->member != (head); \ |
5056 | serge | 499 | pos = list_prev_entry(pos, member)) |
1408 | serge | 500 | |
501 | /** |
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502 | * list_for_each_entry_from - iterate over list of given type from the current point |
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503 | * @pos: the type * to use as a loop cursor. |
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504 | * @head: the head for your list. |
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5270 | serge | 505 | * @member: the name of the list_head within the struct. |
1408 | serge | 506 | * |
507 | * Iterate over list of given type, continuing from current position. |
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508 | */ |
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509 | #define list_for_each_entry_from(pos, head, member) \ |
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6082 | serge | 510 | for (; &pos->member != (head); \ |
5056 | serge | 511 | pos = list_next_entry(pos, member)) |
1408 | serge | 512 | |
513 | /** |
||
514 | * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
||
515 | * @pos: the type * to use as a loop cursor. |
||
516 | * @n: another type * to use as temporary storage |
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517 | * @head: the head for your list. |
||
5270 | serge | 518 | * @member: the name of the list_head within the struct. |
1408 | serge | 519 | */ |
520 | #define list_for_each_entry_safe(pos, n, head, member) \ |
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5056 | serge | 521 | for (pos = list_first_entry(head, typeof(*pos), member), \ |
522 | n = list_next_entry(pos, member); \ |
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1408 | serge | 523 | &pos->member != (head); \ |
5056 | serge | 524 | pos = n, n = list_next_entry(n, member)) |
1408 | serge | 525 | |
526 | /** |
||
1964 | serge | 527 | * list_for_each_entry_safe_continue - continue list iteration safe against removal |
1408 | serge | 528 | * @pos: the type * to use as a loop cursor. |
529 | * @n: another type * to use as temporary storage |
||
530 | * @head: the head for your list. |
||
5270 | serge | 531 | * @member: the name of the list_head within the struct. |
1408 | serge | 532 | * |
533 | * Iterate over list of given type, continuing after current point, |
||
534 | * safe against removal of list entry. |
||
535 | */ |
||
536 | #define list_for_each_entry_safe_continue(pos, n, head, member) \ |
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5056 | serge | 537 | for (pos = list_next_entry(pos, member), \ |
538 | n = list_next_entry(pos, member); \ |
||
1408 | serge | 539 | &pos->member != (head); \ |
5056 | serge | 540 | pos = n, n = list_next_entry(n, member)) |
1408 | serge | 541 | |
542 | /** |
||
1964 | serge | 543 | * list_for_each_entry_safe_from - iterate over list from current point safe against removal |
1408 | serge | 544 | * @pos: the type * to use as a loop cursor. |
545 | * @n: another type * to use as temporary storage |
||
546 | * @head: the head for your list. |
||
5270 | serge | 547 | * @member: the name of the list_head within the struct. |
1408 | serge | 548 | * |
549 | * Iterate over list of given type from current point, safe against |
||
550 | * removal of list entry. |
||
551 | */ |
||
552 | #define list_for_each_entry_safe_from(pos, n, head, member) \ |
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5056 | serge | 553 | for (n = list_next_entry(pos, member); \ |
1408 | serge | 554 | &pos->member != (head); \ |
5056 | serge | 555 | pos = n, n = list_next_entry(n, member)) |
1408 | serge | 556 | |
557 | /** |
||
1964 | serge | 558 | * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal |
1408 | serge | 559 | * @pos: the type * to use as a loop cursor. |
560 | * @n: another type * to use as temporary storage |
||
561 | * @head: the head for your list. |
||
5270 | serge | 562 | * @member: the name of the list_head within the struct. |
1408 | serge | 563 | * |
564 | * Iterate backwards over list of given type, safe against removal |
||
565 | * of list entry. |
||
566 | */ |
||
567 | #define list_for_each_entry_safe_reverse(pos, n, head, member) \ |
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5056 | serge | 568 | for (pos = list_last_entry(head, typeof(*pos), member), \ |
569 | n = list_prev_entry(pos, member); \ |
||
1408 | serge | 570 | &pos->member != (head); \ |
5056 | serge | 571 | pos = n, n = list_prev_entry(n, member)) |
1408 | serge | 572 | |
1964 | serge | 573 | /** |
574 | * list_safe_reset_next - reset a stale list_for_each_entry_safe loop |
||
575 | * @pos: the loop cursor used in the list_for_each_entry_safe loop |
||
576 | * @n: temporary storage used in list_for_each_entry_safe |
||
5270 | serge | 577 | * @member: the name of the list_head within the struct. |
1964 | serge | 578 | * |
579 | * list_safe_reset_next is not safe to use in general if the list may be |
||
580 | * modified concurrently (eg. the lock is dropped in the loop body). An |
||
581 | * exception to this is if the cursor element (pos) is pinned in the list, |
||
582 | * and list_safe_reset_next is called after re-taking the lock and before |
||
583 | * completing the current iteration of the loop body. |
||
584 | */ |
||
585 | #define list_safe_reset_next(pos, n, member) \ |
||
5056 | serge | 586 | n = list_next_entry(pos, member) |
1964 | serge | 587 | |
1408 | serge | 588 | /* |
589 | * Double linked lists with a single pointer list head. |
||
590 | * Mostly useful for hash tables where the two pointer list head is |
||
591 | * too wasteful. |
||
592 | * You lose the ability to access the tail in O(1). |
||
593 | */ |
||
594 | |||
595 | #define HLIST_HEAD_INIT { .first = NULL } |
||
596 | #define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } |
||
597 | #define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) |
||
598 | static inline void INIT_HLIST_NODE(struct hlist_node *h) |
||
599 | { |
||
600 | h->next = NULL; |
||
601 | h->pprev = NULL; |
||
602 | } |
||
603 | |||
604 | static inline int hlist_unhashed(const struct hlist_node *h) |
||
605 | { |
||
606 | return !h->pprev; |
||
607 | } |
||
608 | |||
609 | static inline int hlist_empty(const struct hlist_head *h) |
||
610 | { |
||
611 | return !h->first; |
||
612 | } |
||
613 | |||
614 | static inline void __hlist_del(struct hlist_node *n) |
||
615 | { |
||
616 | struct hlist_node *next = n->next; |
||
617 | struct hlist_node **pprev = n->pprev; |
||
6934 | serge | 618 | |
619 | WRITE_ONCE(*pprev, next); |
||
1408 | serge | 620 | if (next) |
621 | next->pprev = pprev; |
||
622 | } |
||
623 | |||
624 | static inline void hlist_del(struct hlist_node *n) |
||
625 | { |
||
626 | __hlist_del(n); |
||
1964 | serge | 627 | n->next = LIST_POISON1; |
628 | n->pprev = LIST_POISON2; |
||
1408 | serge | 629 | } |
630 | |||
631 | static inline void hlist_del_init(struct hlist_node *n) |
||
632 | { |
||
633 | if (!hlist_unhashed(n)) { |
||
634 | __hlist_del(n); |
||
635 | INIT_HLIST_NODE(n); |
||
636 | } |
||
637 | } |
||
638 | |||
639 | static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) |
||
640 | { |
||
641 | struct hlist_node *first = h->first; |
||
642 | n->next = first; |
||
643 | if (first) |
||
644 | first->pprev = &n->next; |
||
645 | h->first = n; |
||
646 | n->pprev = &h->first; |
||
647 | } |
||
648 | |||
649 | /* next must be != NULL */ |
||
650 | static inline void hlist_add_before(struct hlist_node *n, |
||
651 | struct hlist_node *next) |
||
652 | { |
||
653 | n->pprev = next->pprev; |
||
654 | n->next = next; |
||
655 | next->pprev = &n->next; |
||
656 | *(n->pprev) = n; |
||
657 | } |
||
658 | |||
5056 | serge | 659 | static inline void hlist_add_behind(struct hlist_node *n, |
660 | struct hlist_node *prev) |
||
1408 | serge | 661 | { |
5056 | serge | 662 | n->next = prev->next; |
663 | prev->next = n; |
||
664 | n->pprev = &prev->next; |
||
1408 | serge | 665 | |
5056 | serge | 666 | if (n->next) |
667 | n->next->pprev = &n->next; |
||
1408 | serge | 668 | } |
669 | |||
1964 | serge | 670 | /* after that we'll appear to be on some hlist and hlist_del will work */ |
671 | static inline void hlist_add_fake(struct hlist_node *n) |
||
672 | { |
||
673 | n->pprev = &n->next; |
||
674 | } |
||
675 | |||
6082 | serge | 676 | static inline bool hlist_fake(struct hlist_node *h) |
677 | { |
||
678 | return h->pprev == &h->next; |
||
679 | } |
||
680 | |||
1408 | serge | 681 | /* |
682 | * Move a list from one list head to another. Fixup the pprev |
||
683 | * reference of the first entry if it exists. |
||
684 | */ |
||
685 | static inline void hlist_move_list(struct hlist_head *old, |
||
686 | struct hlist_head *new) |
||
687 | { |
||
688 | new->first = old->first; |
||
689 | if (new->first) |
||
690 | new->first->pprev = &new->first; |
||
691 | old->first = NULL; |
||
692 | } |
||
693 | |||
694 | #define hlist_entry(ptr, type, member) container_of(ptr,type,member) |
||
695 | |||
696 | #define hlist_for_each(pos, head) \ |
||
1970 | serge | 697 | for (pos = (head)->first; pos ; pos = pos->next) |
1408 | serge | 698 | |
699 | #define hlist_for_each_safe(pos, n, head) \ |
||
700 | for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \ |
||
701 | pos = n) |
||
702 | |||
4065 | Serge | 703 | #define hlist_entry_safe(ptr, type, member) \ |
704 | ({ typeof(ptr) ____ptr = (ptr); \ |
||
705 | ____ptr ? hlist_entry(____ptr, type, member) : NULL; \ |
||
706 | }) |
||
707 | |||
1408 | serge | 708 | /** |
709 | * hlist_for_each_entry - iterate over list of given type |
||
4065 | Serge | 710 | * @pos: the type * to use as a loop cursor. |
1408 | serge | 711 | * @head: the head for your list. |
712 | * @member: the name of the hlist_node within the struct. |
||
713 | */ |
||
4065 | Serge | 714 | #define hlist_for_each_entry(pos, head, member) \ |
715 | for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\ |
||
716 | pos; \ |
||
717 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
||
1408 | serge | 718 | |
719 | /** |
||
720 | * hlist_for_each_entry_continue - iterate over a hlist continuing after current point |
||
4065 | Serge | 721 | * @pos: the type * to use as a loop cursor. |
1408 | serge | 722 | * @member: the name of the hlist_node within the struct. |
723 | */ |
||
4065 | Serge | 724 | #define hlist_for_each_entry_continue(pos, member) \ |
725 | for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\ |
||
726 | pos; \ |
||
727 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
||
1408 | serge | 728 | |
729 | /** |
||
730 | * hlist_for_each_entry_from - iterate over a hlist continuing from current point |
||
4065 | Serge | 731 | * @pos: the type * to use as a loop cursor. |
1408 | serge | 732 | * @member: the name of the hlist_node within the struct. |
733 | */ |
||
4065 | Serge | 734 | #define hlist_for_each_entry_from(pos, member) \ |
735 | for (; pos; \ |
||
736 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
||
1408 | serge | 737 | |
738 | /** |
||
739 | * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
||
4065 | Serge | 740 | * @pos: the type * to use as a loop cursor. |
1408 | serge | 741 | * @n: another &struct hlist_node to use as temporary storage |
742 | * @head: the head for your list. |
||
743 | * @member: the name of the hlist_node within the struct. |
||
744 | */ |
||
4065 | Serge | 745 | #define hlist_for_each_entry_safe(pos, n, head, member) \ |
746 | for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\ |
||
747 | pos && ({ n = pos->member.next; 1; }); \ |
||
748 | pos = hlist_entry_safe(n, typeof(*pos), member)) |
||
1408 | serge | 749 | |
750 | #endif |