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Diffstat (limited to 'include/os/linux/spl/sys/list.h')
| -rw-r--r-- | include/os/linux/spl/sys/list.h | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/include/os/linux/spl/sys/list.h b/include/os/linux/spl/sys/list.h new file mode 100644 index 000000000000..be38f328fc65 --- /dev/null +++ b/include/os/linux/spl/sys/list.h @@ -0,0 +1,210 @@ +/* + * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. + * Copyright (C) 2007 The Regents of the University of California. + * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). + * Written by Brian Behlendorf <behlendorf1@llnl.gov>. + * UCRL-CODE-235197 + * + * This file is part of the SPL, Solaris Porting Layer. + * For details, see <http://zfsonlinux.org/>. + * + * The SPL is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * The SPL is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * You should have received a copy of the GNU General Public License along + * with the SPL. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _SPL_LIST_H +#define _SPL_LIST_H + +#include <sys/types.h> +#include <sys/debug.h> +#include <linux/list.h> + +/* + * NOTE: I have implemented the Solaris list API in terms of the native + * linux API. This has certain advantages in terms of leveraging the linux + * list debugging infrastructure, but it also means that the internals of a + * list differ slightly than on Solaris. This is not a problem as long as + * all callers stick to the published API. The two major differences are: + * + * 1) A list_node_t is mapped to a linux list_head struct which changes + * the name of the list_next/list_prev pointers to next/prev respectively. + * + * 2) A list_node_t which is not attached to a list on Solaris is denoted + * by having its list_next/list_prev pointers set to NULL. Under linux + * the next/prev pointers are set to LIST_POISON1 and LIST_POISON2 + * respectively. At this moment this only impacts the implementation + * of the list_link_init() and list_link_active() functions. + */ + +typedef struct list_head list_node_t; + +typedef struct list { + size_t list_size; + size_t list_offset; + list_node_t list_head; +} list_t; + +#define list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset)) +#define list_object(a, node) ((void *)(((char *)node) - (a)->list_offset)) + +static inline int +list_is_empty(list_t *list) +{ + return (list_empty(&list->list_head)); +} + +static inline void +list_link_init(list_node_t *node) +{ + node->next = LIST_POISON1; + node->prev = LIST_POISON2; +} + +static inline void +list_create(list_t *list, size_t size, size_t offset) +{ + list->list_size = size; + list->list_offset = offset; + INIT_LIST_HEAD(&list->list_head); +} + +static inline void +list_destroy(list_t *list) +{ + list_del(&list->list_head); +} + +static inline void +list_insert_head(list_t *list, void *object) +{ + list_add(list_d2l(list, object), &list->list_head); +} + +static inline void +list_insert_tail(list_t *list, void *object) +{ + list_add_tail(list_d2l(list, object), &list->list_head); +} + +static inline void +list_insert_after(list_t *list, void *object, void *nobject) +{ + if (object == NULL) + list_insert_head(list, nobject); + else + list_add(list_d2l(list, nobject), list_d2l(list, object)); +} + +static inline void +list_insert_before(list_t *list, void *object, void *nobject) +{ + if (object == NULL) + list_insert_tail(list, nobject); + else + list_add_tail(list_d2l(list, nobject), list_d2l(list, object)); +} + +static inline void +list_remove(list_t *list, void *object) +{ + list_del(list_d2l(list, object)); +} + +static inline void * +list_remove_head(list_t *list) +{ + list_node_t *head = list->list_head.next; + if (head == &list->list_head) + return (NULL); + + list_del(head); + return (list_object(list, head)); +} + +static inline void * +list_remove_tail(list_t *list) +{ + list_node_t *tail = list->list_head.prev; + if (tail == &list->list_head) + return (NULL); + + list_del(tail); + return (list_object(list, tail)); +} + +static inline void * +list_head(list_t *list) +{ + if (list_is_empty(list)) + return (NULL); + + return (list_object(list, list->list_head.next)); +} + +static inline void * +list_tail(list_t *list) +{ + if (list_is_empty(list)) + return (NULL); + + return (list_object(list, list->list_head.prev)); +} + +static inline void * +list_next(list_t *list, void *object) +{ + list_node_t *node = list_d2l(list, object); + + if (node->next != &list->list_head) + return (list_object(list, node->next)); + + return (NULL); +} + +static inline void * +list_prev(list_t *list, void *object) +{ + list_node_t *node = list_d2l(list, object); + + if (node->prev != &list->list_head) + return (list_object(list, node->prev)); + + return (NULL); +} + +static inline int +list_link_active(list_node_t *node) +{ + EQUIV(node->next == LIST_POISON1, node->prev == LIST_POISON2); + return (node->next != LIST_POISON1); +} + +static inline void +spl_list_move_tail(list_t *dst, list_t *src) +{ + list_splice_init(&src->list_head, dst->list_head.prev); +} + +#define list_move_tail(dst, src) spl_list_move_tail(dst, src) + +static inline void +list_link_replace(list_node_t *old_node, list_node_t *new_node) +{ + new_node->next = old_node->next; + new_node->prev = old_node->prev; + old_node->prev->next = new_node; + old_node->next->prev = new_node; + list_link_init(old_node); +} + +#endif /* SPL_LIST_H */ |