| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * 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 */ |
| PG_CONTENDED1, /* Is someone waiting for a lock? */ |
| PG_CONTENDED2, /* Is someone waiting for a lock? */ |
| }; |
| |
| 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_lock_context *wb_lock_context; /* lock context info */ |
| pgoff_t wb_index; /* Offset >> PAGE_SHIFT */ |
| unsigned int wb_offset, /* Offset & ~PAGE_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 */ |
| unsigned short wb_nio; /* Number of I/O attempts */ |
| }; |
| |
| struct nfs_pgio_mirror; |
| 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_pgio_mirror * |
| (*pg_get_mirror)(struct nfs_pageio_descriptor *, u32); |
| u32 (*pg_set_mirror)(struct nfs_pageio_descriptor *, u32); |
| }; |
| |
| struct nfs_rw_ops { |
| struct nfs_pgio_header *(*rw_alloc_header)(void); |
| void (*rw_free_header)(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 { |
| 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_io_completion *pg_io_completion; |
| struct nfs_direct_req *pg_dreq; |
| 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 */ |
| unsigned short pg_maxretrans; |
| unsigned char pg_moreio : 1; |
| }; |
| |
| /* 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, |
| 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 struct nfs_page *nfs_page_group_lock_head(struct nfs_page *req); |
| extern int nfs_page_group_lock_subrequests(struct nfs_page *head); |
| extern void nfs_join_page_group(struct nfs_page *head, struct inode *inode); |
| extern int nfs_page_group_lock(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); |
| extern int nfs_page_set_headlock(struct nfs_page *req); |
| extern void nfs_page_clear_headlock(struct nfs_page *req); |
| extern bool nfs_async_iocounter_wait(struct rpc_task *, struct nfs_lock_context *); |
| |
| /* |
| * 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_move_request - Move a request to a new list |
| * @req: request |
| * @head: head of list into which to insert the request. |
| */ |
| static inline void |
| nfs_list_move_request(struct nfs_page *req, struct list_head *head) |
| { |
| list_move_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_SHIFT) + req->wb_offset; |
| } |
| |
| static inline struct nfs_open_context * |
| nfs_req_openctx(struct nfs_page *req) |
| { |
| return req->wb_lock_context->open_context; |
| } |
| |
| #endif /* _LINUX_NFS_PAGE_H */ |