diff options
Diffstat (limited to 'kernel/include/linux/nfs_page.h')
| -rw-r--r-- | kernel/include/linux/nfs_page.h | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/kernel/include/linux/nfs_page.h b/kernel/include/linux/nfs_page.h new file mode 100644 index 000000000..3eb072dbc --- /dev/null +++ b/kernel/include/linux/nfs_page.h @@ -0,0 +1,191 @@ +/* + * 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 a dirty buffer + */ +enum { + PG_BUSY = 0, /* nfs_{un}lock_request */ + PG_MAPPED, /* page private set for buffered io */ + PG_CLEAN, /* write succeeded */ + PG_COMMIT_TO_DS, /* used by pnfs layouts */ + PG_INODE_REF, /* extra ref held by inode when in writeback */ + PG_HEADLOCK, /* page group lock of wb_head */ + PG_TEARDOWN, /* page group sync for destroy */ + PG_UNLOCKPAGE, /* page group sync bit in read path */ + PG_UPTODATE, /* page group sync bit in read path */ + PG_WB_END, /* page group sync bit in write path */ + PG_REMOVE, /* page group sync bit in write path */ +}; + +struct nfs_inode; +struct nfs_page { + struct list_head wb_list; /* Defines state of page: */ + 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 */ + 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_write_verifier wb_verf; /* Commit cookie */ + struct nfs_page *wb_this_page; /* list of reqs for this page */ + struct nfs_page *wb_head; /* head pointer for req list */ +}; + +struct nfs_pageio_descriptor; +struct nfs_pageio_ops { + void (*pg_init)(struct nfs_pageio_descriptor *, struct nfs_page *); + size_t (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, + struct nfs_page *); + int (*pg_doio)(struct nfs_pageio_descriptor *); + unsigned int (*pg_get_mirror_count)(struct nfs_pageio_descriptor *, + struct nfs_page *); + void (*pg_cleanup)(struct nfs_pageio_descriptor *); +}; + +struct nfs_rw_ops { + const fmode_t rw_mode; + struct nfs_pgio_header *(*rw_alloc_header)(void); + void (*rw_free_header)(struct nfs_pgio_header *); + void (*rw_release)(struct nfs_pgio_header *); + int (*rw_done)(struct rpc_task *, struct nfs_pgio_header *, + struct inode *); + void (*rw_result)(struct rpc_task *, struct nfs_pgio_header *); + void (*rw_initiate)(struct nfs_pgio_header *, struct rpc_message *, + const struct nfs_rpc_ops *, + struct rpc_task_setup *, int); +}; + +struct nfs_pgio_mirror { + struct list_head pg_list; + unsigned long pg_bytes_written; + size_t pg_count; + size_t pg_bsize; + unsigned int pg_base; + unsigned char pg_recoalesce : 1; +}; + +struct nfs_pageio_descriptor { + unsigned char pg_moreio : 1; + struct inode *pg_inode; + const struct nfs_pageio_ops *pg_ops; + const struct nfs_rw_ops *pg_rw_ops; + int pg_ioflags; + int pg_error; + const struct rpc_call_ops *pg_rpc_callops; + const struct nfs_pgio_completion_ops *pg_completion_ops; + struct pnfs_layout_segment *pg_lseg; + struct nfs_direct_req *pg_dreq; + void *pg_layout_private; + unsigned int pg_bsize; /* default bsize for mirrors */ + + u32 pg_mirror_count; + struct nfs_pgio_mirror *pg_mirrors; + struct nfs_pgio_mirror pg_mirrors_static[1]; + struct nfs_pgio_mirror *pg_mirrors_dynamic; + u32 pg_mirror_idx; /* current mirror */ +}; + +/* arbitrarily selected limit to number of mirrors */ +#define NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX 16 + +#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 page *page, + struct nfs_page *last, + unsigned int offset, + unsigned int count); +extern void nfs_release_request(struct nfs_page *); + + +extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc, + struct inode *inode, + const struct nfs_pageio_ops *pg_ops, + const struct nfs_pgio_completion_ops *compl_ops, + const struct nfs_rw_ops *rw_ops, + size_t bsize, + int how); +extern int nfs_pageio_add_request(struct nfs_pageio_descriptor *, + struct nfs_page *); +extern int nfs_pageio_resend(struct nfs_pageio_descriptor *, + struct nfs_pgio_header *); +extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc); +extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t); +extern size_t 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 void nfs_unlock_and_release_request(struct nfs_page *); +extern int nfs_page_group_lock(struct nfs_page *, bool); +extern void nfs_page_group_lock_wait(struct nfs_page *); +extern void nfs_page_group_unlock(struct nfs_page *); +extern bool nfs_page_group_sync_on_bit(struct nfs_page *, unsigned int); + +/* + * Lock the page of an asynchronous request + */ +static inline int +nfs_lock_request(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 */ |