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 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 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 } 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 } 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 } 66 static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v) 67 { 68 return ceph_pagelist_append(pl, &v, 1); 69 } 70 static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl, 71 char *s, size_t 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