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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/nfs_page.h | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/linux/nfs_page.h')
-rw-r--r-- | include/linux/nfs_page.h | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h new file mode 100644 index 000000000000..39e4895bcdb4 --- /dev/null +++ b/include/linux/nfs_page.h @@ -0,0 +1,151 @@ +/* + * 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/nfs_fs_sb.h> +#include <linux/sunrpc/auth.h> +#include <linux/nfs_xdr.h> + +#include <asm/atomic.h> + +/* + * Valid flags for a dirty buffer + */ +#define PG_BUSY 0 +#define PG_NEED_COMMIT 1 +#define PG_NEED_RESCHED 2 + +struct nfs_page { + struct list_head wb_list, /* Defines state of page: */ + *wb_list_head; /* read/write/commit */ + struct page *wb_page; /* page to read in/write out */ + struct nfs_open_context *wb_context; /* File state context info */ + atomic_t wb_complete; /* i/os we're waiting for */ + unsigned long 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 */ + atomic_t wb_count; /* reference count */ + unsigned long wb_flags; + struct nfs_writeverf wb_verf; /* Commit cookie */ +}; + +#define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags)) +#define NFS_NEED_COMMIT(req) (test_bit(PG_NEED_COMMIT,&(req)->wb_flags)) +#define NFS_NEED_RESCHED(req) (test_bit(PG_NEED_RESCHED,&(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_clear_request(struct nfs_page *req); +extern void nfs_release_request(struct nfs_page *req); + + +extern void nfs_list_add_request(struct nfs_page *, struct list_head *); + +extern int nfs_scan_list(struct list_head *, struct list_head *, + unsigned long, unsigned int); +extern int nfs_coalesce_requests(struct list_head *, struct list_head *, + unsigned int); +extern int nfs_wait_on_request(struct nfs_page *); +extern void nfs_unlock_request(struct nfs_page *req); + +/* + * Lock the page of an asynchronous request without incrementing the wb_count + */ +static inline int +nfs_lock_request_dontget(struct nfs_page *req) +{ + if (test_and_set_bit(PG_BUSY, &req->wb_flags)) + return 0; + return 1; +} + +/* + * Lock the page of an asynchronous request + */ +static inline int +nfs_lock_request(struct nfs_page *req) +{ + if (test_and_set_bit(PG_BUSY, &req->wb_flags)) + return 0; + atomic_inc(&req->wb_count); + return 1; +} + + +/** + * 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; + if (!NFS_WBACK_BUSY(req)) { + printk(KERN_ERR "NFS: unlocked request attempted removed from list!\n"); + BUG(); + } + list_del_init(&req->wb_list); + req->wb_list_head = NULL; +} + +static inline int +nfs_defer_commit(struct nfs_page *req) +{ + if (test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags)) + return 0; + return 1; +} + +static inline void +nfs_clear_commit(struct nfs_page *req) +{ + smp_mb__before_clear_bit(); + clear_bit(PG_NEED_COMMIT, &req->wb_flags); + smp_mb__after_clear_bit(); +} + +static inline int +nfs_defer_reschedule(struct nfs_page *req) +{ + if (test_and_set_bit(PG_NEED_RESCHED, &req->wb_flags)) + return 0; + return 1; +} + +static inline void +nfs_clear_reschedule(struct nfs_page *req) +{ + smp_mb__before_clear_bit(); + clear_bit(PG_NEED_RESCHED, &req->wb_flags); + smp_mb__after_clear_bit(); +} + +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 */ |