1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/*
* linux/include/linux/nfs_page.h
*
* Copyright (C) 2000 Trond Myklebust
*
* NFS page cache wrapper.
*/
#ifndef _LINUX_NFS_PAGE_H
#define _LINUX_NFS_PAGE_H
#include <linux/list.h>
#include <linux/pagemap.h>
#include <linux/wait.h>
#include <linux/sunrpc/auth.h>
#include <linux/nfs_xdr.h>
#include <linux/kref.h>
/*
* Valid flags for the radix tree
*/
#define NFS_PAGE_TAG_LOCKED 0
#define NFS_PAGE_TAG_COMMIT 1
/*
* Valid flags for a dirty buffer
*/
enum {
PG_BUSY = 0,
PG_MAPPED,
PG_CLEAN,
PG_NEED_COMMIT,
PG_NEED_RESCHED,
PG_PNFS_COMMIT,
};
struct nfs_inode;
struct nfs_page {
union {
struct list_head wb_list; /* Defines state of page: */
struct pnfs_layout_segment *wb_commit_lseg; /* Used when PG_PNFS_COMMIT set */
};
struct page *wb_page; /* page to read in/write out */
struct nfs_open_context *wb_context; /* File state context info */
struct nfs_lock_context *wb_lock_context; /* lock context info */
atomic_t wb_complete; /* i/os we're waiting for */
pgoff_t wb_index; /* Offset >> PAGE_CACHE_SHIFT */
unsigned int wb_offset, /* Offset & ~PAGE_CACHE_MASK */
wb_pgbase, /* Start of page data */
wb_bytes; /* Length of request */
struct kref wb_kref; /* reference count */
unsigned long wb_flags;
struct nfs_writeverf wb_verf; /* Commit cookie */
};
struct nfs_pageio_descriptor;
struct nfs_pageio_ops {
bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
int (*pg_doio)(struct nfs_pageio_descriptor *);
};
struct nfs_pageio_descriptor {
struct list_head pg_list;
unsigned long pg_bytes_written;
size_t pg_count;
size_t pg_bsize;
unsigned int pg_base;
char pg_moreio;
struct inode *pg_inode;
const struct nfs_pageio_ops *pg_ops;
int pg_ioflags;
int pg_error;
struct pnfs_layout_segment *pg_lseg;
};
#define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
extern struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
struct inode *inode,
struct page *page,
unsigned int offset,
unsigned int count);
extern void nfs_release_request(struct nfs_page *req);
extern int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *dst,
pgoff_t idx_start, unsigned int npages, int tag);
extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
struct inode *inode,
const struct nfs_pageio_ops *pg_ops,
size_t bsize,
int how);
extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *,
struct nfs_page *);
extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
extern bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
struct nfs_page *prev,
struct nfs_page *req);
extern int nfs_wait_on_request(struct nfs_page *);
extern void nfs_unlock_request(struct nfs_page *req);
extern int nfs_set_page_tag_locked(struct nfs_page *req);
extern void nfs_clear_page_tag_locked(struct nfs_page *req);
extern int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
extern int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc);
/*
* Lock the page of an asynchronous request without getting a new reference
*/
static inline int
nfs_lock_request_dontget(struct nfs_page *req)
{
return !test_and_set_bit(PG_BUSY, &req->wb_flags);
}
/**
* nfs_list_add_request - Insert a request into a list
* @req: request
* @head: head of list into which to insert the request.
*/
static inline void
nfs_list_add_request(struct nfs_page *req, struct list_head *head)
{
list_add_tail(&req->wb_list, head);
}
/**
* nfs_list_remove_request - Remove a request from its wb_list
* @req: request
*/
static inline void
nfs_list_remove_request(struct nfs_page *req)
{
if (list_empty(&req->wb_list))
return;
list_del_init(&req->wb_list);
}
static inline struct nfs_page *
nfs_list_entry(struct list_head *head)
{
return list_entry(head, struct nfs_page, wb_list);
}
static inline
loff_t req_offset(struct nfs_page *req)
{
return (((loff_t)req->wb_index) << PAGE_CACHE_SHIFT) + req->wb_offset;
}
#endif /* _LINUX_NFS_PAGE_H */
|
