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 
26 struct ceph_pagelist *ceph_pagelist_alloc(gfp_t gfp_flags);
27 
28 extern void ceph_pagelist_release(struct ceph_pagelist *pl);
29 
30 extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
31 
32 extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
33 
34 extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
35 
36 extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
37 				     struct ceph_pagelist_cursor *c);
38 
39 extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
40 				  struct ceph_pagelist_cursor *c);
41 
ceph_pagelist_encode_64(struct ceph_pagelist * pl,u64 v)42 static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
43 {
44 	__le64 ev = cpu_to_le64(v);
45 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
46 }
ceph_pagelist_encode_32(struct ceph_pagelist * pl,u32 v)47 static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
48 {
49 	__le32 ev = cpu_to_le32(v);
50 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
51 }
ceph_pagelist_encode_16(struct ceph_pagelist * pl,u16 v)52 static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
53 {
54 	__le16 ev = cpu_to_le16(v);
55 	return ceph_pagelist_append(pl, &ev, sizeof(ev));
56 }
ceph_pagelist_encode_8(struct ceph_pagelist * pl,u8 v)57 static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
58 {
59 	return ceph_pagelist_append(pl, &v, 1);
60 }
ceph_pagelist_encode_string(struct ceph_pagelist * pl,char * s,u32 len)61 static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
62 					      char *s, u32 len)
63 {
64 	int ret = ceph_pagelist_encode_32(pl, len);
65 	if (ret)
66 		return ret;
67 	if (len)
68 		return ceph_pagelist_append(pl, s, len);
69 	return 0;
70 }
71 
72 #endif
73