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_COMMIT 1
27 * Valid flags for a dirty buffer
36 PG_PARTIAL_READ_FAILED,
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 nfs_pageio_ops {
60 void (*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *);
61 bool (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
62 int (*pg_doio)(struct nfs_pageio_descriptor *);
65 struct nfs_pageio_descriptor {
66 struct list_head pg_list;
67 unsigned long pg_bytes_written;
71 unsigned char pg_moreio : 1,
74 struct inode *pg_inode;
75 const struct nfs_pageio_ops *pg_ops;
78 const struct rpc_call_ops *pg_rpc_callops;
79 struct pnfs_layout_segment *pg_lseg;
82 #define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
84 extern struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
89 extern void nfs_release_request(struct nfs_page *req);
92 extern int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *dst,
93 pgoff_t idx_start, unsigned int npages, int tag);
94 extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
96 const struct nfs_pageio_ops *pg_ops,
99 extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *,
101 extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
102 extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
103 extern bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
104 struct nfs_page *prev,
105 struct nfs_page *req);
106 extern int nfs_wait_on_request(struct nfs_page *);
107 extern void nfs_unlock_request(struct nfs_page *req);
110 * Lock the page of an asynchronous request without getting a new reference
113 nfs_lock_request_dontget(struct nfs_page *req)
115 return !test_and_set_bit(PG_BUSY, &req->wb_flags);
119 * nfs_list_add_request - Insert a request into a list
121 * @head: head of list into which to insert the request.
124 nfs_list_add_request(struct nfs_page *req, struct list_head *head)
126 list_add_tail(&req->wb_list, head);
131 * nfs_list_remove_request - Remove a request from its wb_list
135 nfs_list_remove_request(struct nfs_page *req)
137 if (list_empty(&req->wb_list))
139 list_del_init(&req->wb_list);
142 static inline struct nfs_page *
143 nfs_list_entry(struct list_head *head)
145 return list_entry(head, struct nfs_page, wb_list);
149 loff_t req_offset(struct nfs_page *req)
151 return (((loff_t)req->wb_index) << PAGE_CACHE_SHIFT) + req->wb_offset;
154 #endif /* _LINUX_NFS_PAGE_H */