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
42 struct list_head wb_list
; /* Defines state of page: */
43 struct pnfs_layout_segment
*wb_commit_lseg
; /* Used when PG_PNFS_COMMIT set */
45 struct page
*wb_page
; /* page to read in/write out */
46 struct nfs_open_context
*wb_context
; /* File state context info */
47 struct nfs_lock_context
*wb_lock_context
; /* lock context info */
48 atomic_t wb_complete
; /* i/os we're waiting for */
49 pgoff_t wb_index
; /* Offset >> PAGE_CACHE_SHIFT */
50 unsigned int wb_offset
, /* Offset & ~PAGE_CACHE_MASK */
51 wb_pgbase
, /* Start of page data */
52 wb_bytes
; /* Length of request */
53 struct kref wb_kref
; /* reference count */
54 unsigned long wb_flags
;
55 struct nfs_writeverf wb_verf
; /* Commit cookie */
58 struct nfs_pageio_descriptor
{
59 struct list_head pg_list
;
60 unsigned long pg_bytes_written
;
66 struct inode
*pg_inode
;
67 int (*pg_doio
)(struct nfs_pageio_descriptor
*);
70 struct pnfs_layout_segment
*pg_lseg
;
71 int (*pg_test
)(struct nfs_pageio_descriptor
*, struct nfs_page
*, struct nfs_page
*);
74 #define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
76 extern struct nfs_page
*nfs_create_request(struct nfs_open_context
*ctx
,
81 extern void nfs_release_request(struct nfs_page
*req
);
84 extern int nfs_scan_list(struct nfs_inode
*nfsi
, struct list_head
*dst
,
85 pgoff_t idx_start
, unsigned int npages
, int tag
);
86 extern void nfs_pageio_init(struct nfs_pageio_descriptor
*desc
,
88 int (*doio
)(struct nfs_pageio_descriptor
*desc
),
91 extern int nfs_pageio_add_request(struct nfs_pageio_descriptor
*,
93 extern void nfs_pageio_complete(struct nfs_pageio_descriptor
*desc
);
94 extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor
*, pgoff_t
);
95 extern int nfs_wait_on_request(struct nfs_page
*);
96 extern void nfs_unlock_request(struct nfs_page
*req
);
97 extern int nfs_set_page_tag_locked(struct nfs_page
*req
);
98 extern void nfs_clear_page_tag_locked(struct nfs_page
*req
);
102 * Lock the page of an asynchronous request without getting a new reference
105 nfs_lock_request_dontget(struct nfs_page
*req
)
107 return !test_and_set_bit(PG_BUSY
, &req
->wb_flags
);
111 * nfs_list_add_request - Insert a request into a list
113 * @head: head of list into which to insert the request.
116 nfs_list_add_request(struct nfs_page
*req
, struct list_head
*head
)
118 list_add_tail(&req
->wb_list
, head
);
123 * nfs_list_remove_request - Remove a request from its wb_list
127 nfs_list_remove_request(struct nfs_page
*req
)
129 if (list_empty(&req
->wb_list
))
131 list_del_init(&req
->wb_list
);
134 static inline struct nfs_page
*
135 nfs_list_entry(struct list_head
*head
)
137 return list_entry(head
, struct nfs_page
, wb_list
);
141 loff_t
req_offset(struct nfs_page
*req
)
143 return (((loff_t
)req
->wb_index
) << PAGE_CACHE_SHIFT
) + req
->wb_offset
;
146 #endif /* _LINUX_NFS_PAGE_H */