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
10struct 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
20struct 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
26struct ceph_pagelist *ceph_pagelist_alloc(gfp_t gfp_flags);
27
28extern void ceph_pagelist_release(struct ceph_pagelist *pl);
29
30extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
31
32extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
33
34extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
35
36extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
37				     struct ceph_pagelist_cursor *c);
38
39extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
40				  struct ceph_pagelist_cursor *c);
41
42static 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}
47static 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}
52static 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}
57static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
58{
59	return ceph_pagelist_append(pl, &v, 1);
60}
61static 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