1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __FS_CEPH_PAGELIST_H
3 #define __FS_CEPH_PAGELIST_H
4 
5 #include <asm/byteorder.h>
6 #include <linux/refcount.h>
7 #include <linux/list.h>
8 #include <linux/types.h>
9 
10 struct ceph_pagelist {
11 	struct list_head head;
12 	void *mapped_tail;
13 	size_t length;
14 	size_t room;
15 	struct list_head free_list;
16 	size_t num_pages_free;
17 	refcount_t refcnt;
18 };
19 
20 struct ceph_pagelist_cursor {
21 	struct ceph_pagelist *pl;   /* pagelist, for error checking */
22 	struct list_head *page_lru; /* page in list */
23 	size_t room;		    /* room remaining to reset to */
24 };
25 
ceph_pagelist_init(struct ceph_pagelist * pl)26 static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
27 {
28 	INIT_LIST_HEAD(&pl->head);
29 	pl->mapped_tail = NULL;
30 	pl->length = 0;
31 	pl->room = 0;
32 	INIT_LIST_HEAD(&pl->free_list);
33 	pl->num_pages_free = 0;
34 	refcount_set(&pl->refcnt, 1);
35 }
36 
37 extern void ceph_pagelist_release(struct ceph_pagelist *pl);
38 
39 extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
40 
41 extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
42 
43 extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
44 
45 extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
46 				     struct ceph_pagelist_cursor *c);
47 
48 extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
49 				  struct ceph_pagelist_cursor *c);
50 
ceph_pagelist_encode_64(struct ceph_pagelist * pl,u64 v)51 static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
52 {
53 	__le64 ev = cpu_to_le64(v);
54 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
55 }
ceph_pagelist_encode_32(struct ceph_pagelist * pl,u32 v)56 static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
57 {
58 	__le32 ev = cpu_to_le32(v);
59 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
60 }
ceph_pagelist_encode_16(struct ceph_pagelist * pl,u16 v)61 static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
62 {
63 	__le16 ev = cpu_to_le16(v);
64 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
65 }
ceph_pagelist_encode_8(struct ceph_pagelist * pl,u8 v)66 static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
67 {
68 	return ceph_pagelist_append(pl, &v, 1);
69 }
ceph_pagelist_encode_string(struct ceph_pagelist * pl,char * s,u32 len)70 static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
71 					      char *s, u32 len)
72 {
73 	int ret = ceph_pagelist_encode_32(pl, len);
74 	if (ret)
75 		return ret;
76 	if (len)
77 		return ceph_pagelist_append(pl, s, len);
78 	return 0;
79 }
80 
81 #endif
82