2 * linux/include/linux/nfs_page.h
4 * Copyright (C) 2000 Trond Myklebust
6 * NFS page cache wrapper.
9 #ifndef _LINUX_NFS_PAGE_H
10 #define _LINUX_NFS_PAGE_H
13 #include <linux/list.h>
14 #include <linux/pagemap.h>
15 #include <linux/wait.h>
16 #include <linux/sunrpc/auth.h>
17 #include <linux/nfs_xdr.h>
19 #include <linux/kref.h>
22 * Valid flags for the radix tree
24 #define NFS_PAGE_TAG_LOCKED 0
25 #define NFS_PAGE_TAG_COMMIT 1
28 * Valid flags for a dirty buffer
39 struct list_head wb_list
; /* Defines state of page: */
40 struct page
*wb_page
; /* page to read in/write out */
41 struct nfs_open_context
*wb_context
; /* File state context info */
42 atomic_t wb_complete
; /* i/os we're waiting for */
43 pgoff_t wb_index
; /* Offset >> PAGE_CACHE_SHIFT */
44 unsigned int wb_offset
, /* Offset & ~PAGE_CACHE_MASK */
45 wb_pgbase
, /* Start of page data */
46 wb_bytes
; /* Length of request */
47 struct kref wb_kref
; /* reference count */
48 unsigned long wb_flags
;
49 struct nfs_writeverf wb_verf
; /* Commit cookie */
52 struct nfs_pageio_descriptor
{
53 struct list_head pg_list
;
54 unsigned long pg_bytes_written
;
59 struct inode
*pg_inode
;
60 int (*pg_doio
)(struct inode
*, struct list_head
*, unsigned int, size_t, int);
65 #define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
67 extern struct nfs_page
*nfs_create_request(struct nfs_open_context
*ctx
,
72 extern void nfs_clear_request(struct nfs_page
*req
);
73 extern void nfs_release_request(struct nfs_page
*req
);
76 extern int nfs_scan_list(struct nfs_inode
*nfsi
, struct list_head
*dst
,
77 pgoff_t idx_start
, unsigned int npages
, int tag
);
78 extern void nfs_pageio_init(struct nfs_pageio_descriptor
*desc
,
80 int (*doio
)(struct inode
*, struct list_head
*, unsigned int, size_t, int),
83 extern int nfs_pageio_add_request(struct nfs_pageio_descriptor
*,
85 extern void nfs_pageio_complete(struct nfs_pageio_descriptor
*desc
);
86 extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor
*, pgoff_t
);
87 extern int nfs_wait_on_request(struct nfs_page
*);
88 extern void nfs_unlock_request(struct nfs_page
*req
);
89 extern int nfs_set_page_tag_locked(struct nfs_page
*req
);
90 extern void nfs_clear_page_tag_locked(struct nfs_page
*req
);
94 * Lock the page of an asynchronous request without getting a new reference
97 nfs_lock_request_dontget(struct nfs_page
*req
)
99 return !test_and_set_bit(PG_BUSY
, &req
->wb_flags
);
103 * nfs_list_add_request - Insert a request into a list
105 * @head: head of list into which to insert the request.
108 nfs_list_add_request(struct nfs_page
*req
, struct list_head
*head
)
110 list_add_tail(&req
->wb_list
, head
);
115 * nfs_list_remove_request - Remove a request from its wb_list
119 nfs_list_remove_request(struct nfs_page
*req
)
121 if (list_empty(&req
->wb_list
))
123 list_del_init(&req
->wb_list
);
126 static inline struct nfs_page
*
127 nfs_list_entry(struct list_head
*head
)
129 return list_entry(head
, struct nfs_page
, wb_list
);
133 loff_t
req_offset(struct nfs_page
*req
)
135 return (((loff_t
)req
->wb_index
) << PAGE_CACHE_SHIFT
) + req
->wb_offset
;
138 #endif /* _LINUX_NFS_PAGE_H */