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	 a911fd9a60
			
		
	
	
		a911fd9a60
		
	
	
	
	
		
			
			Minor cleanup: inlined bit ops in nfs_page.h can be simpler. Test plan: Write-intensive workload against a server that requires COMMITs. Signed-off-by: Chuck Lever <cel@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
		
			
				
	
	
		
			163 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			163 lines
		
	
	
	
		
			4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * linux/include/linux/nfs_page.h
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|  *
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|  * Copyright (C) 2000 Trond Myklebust
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|  *
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|  * NFS page cache wrapper.
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|  */
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| 
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| #ifndef _LINUX_NFS_PAGE_H
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| #define _LINUX_NFS_PAGE_H
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| 
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| 
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| #include <linux/list.h>
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| #include <linux/pagemap.h>
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| #include <linux/wait.h>
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| #include <linux/nfs_fs_sb.h>
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| #include <linux/sunrpc/auth.h>
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| #include <linux/nfs_xdr.h>
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| 
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| #include <asm/atomic.h>
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| 
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| /*
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|  * Valid flags for the radix tree
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|  */
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| #define NFS_PAGE_TAG_DIRTY	0
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| #define NFS_PAGE_TAG_WRITEBACK	1
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| 
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| /*
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|  * Valid flags for a dirty buffer
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|  */
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| #define PG_BUSY			0
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| #define PG_NEED_COMMIT		1
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| #define PG_NEED_RESCHED		2
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| 
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| struct nfs_inode;
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| struct nfs_page {
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| 	struct list_head	wb_list,	/* Defines state of page: */
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| 				*wb_list_head;	/*      read/write/commit */
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| 	struct page		*wb_page;	/* page to read in/write out */
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| 	struct nfs_open_context	*wb_context;	/* File state context info */
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| 	atomic_t		wb_complete;	/* i/os we're waiting for */
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| 	unsigned long		wb_index;	/* Offset >> PAGE_CACHE_SHIFT */
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| 	unsigned int		wb_offset,	/* Offset & ~PAGE_CACHE_MASK */
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| 				wb_pgbase,	/* Start of page data */
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| 				wb_bytes;	/* Length of request */
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| 	atomic_t		wb_count;	/* reference count */
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| 	unsigned long		wb_flags;
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| 	struct nfs_writeverf	wb_verf;	/* Commit cookie */
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| };
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| 
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| #define NFS_WBACK_BUSY(req)	(test_bit(PG_BUSY,&(req)->wb_flags))
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| #define NFS_NEED_COMMIT(req)	(test_bit(PG_NEED_COMMIT,&(req)->wb_flags))
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| #define NFS_NEED_RESCHED(req)	(test_bit(PG_NEED_RESCHED,&(req)->wb_flags))
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| 
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| extern	struct nfs_page *nfs_create_request(struct nfs_open_context *ctx,
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| 					    struct inode *inode,
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| 					    struct page *page,
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| 					    unsigned int offset,
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| 					    unsigned int count);
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| extern	void nfs_clear_request(struct nfs_page *req);
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| extern	void nfs_release_request(struct nfs_page *req);
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| 
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| 
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| extern  int nfs_scan_lock_dirty(struct nfs_inode *nfsi, struct list_head *dst,
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| 				unsigned long idx_start, unsigned int npages);
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| extern	int nfs_scan_list(struct list_head *, struct list_head *,
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| 			  unsigned long, unsigned int);
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| extern	int nfs_coalesce_requests(struct list_head *, struct list_head *,
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| 				  unsigned int);
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| extern  int nfs_wait_on_request(struct nfs_page *);
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| extern	void nfs_unlock_request(struct nfs_page *req);
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| extern  int nfs_set_page_writeback_locked(struct nfs_page *req);
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| extern  void nfs_clear_page_writeback(struct nfs_page *req);
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| 
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| 
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| /*
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|  * Lock the page of an asynchronous request without incrementing the wb_count
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|  */
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| static inline int
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| nfs_lock_request_dontget(struct nfs_page *req)
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| {
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| 	return !test_and_set_bit(PG_BUSY, &req->wb_flags);
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| }
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| 
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| /*
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|  * Lock the page of an asynchronous request
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|  */
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| static inline int
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| nfs_lock_request(struct nfs_page *req)
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| {
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| 	if (test_and_set_bit(PG_BUSY, &req->wb_flags))
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| 		return 0;
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| 	atomic_inc(&req->wb_count);
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| 	return 1;
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| }
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| 
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| /**
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|  * nfs_list_add_request - Insert a request into a list
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|  * @req: request
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|  * @head: head of list into which to insert the request.
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|  */
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| static inline void
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| nfs_list_add_request(struct nfs_page *req, struct list_head *head)
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| {
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| 	list_add_tail(&req->wb_list, head);
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| 	req->wb_list_head = head;
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| }
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| 
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| 
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| /**
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|  * nfs_list_remove_request - Remove a request from its wb_list
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|  * @req: request
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|  */
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| static inline void
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| nfs_list_remove_request(struct nfs_page *req)
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| {
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| 	if (list_empty(&req->wb_list))
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| 		return;
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| 	list_del_init(&req->wb_list);
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| 	req->wb_list_head = NULL;
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| }
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| 
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| static inline int
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| nfs_defer_commit(struct nfs_page *req)
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| {
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| 	return !test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags);
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| }
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| 
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| static inline void
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| nfs_clear_commit(struct nfs_page *req)
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| {
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| 	smp_mb__before_clear_bit();
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| 	clear_bit(PG_NEED_COMMIT, &req->wb_flags);
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| 	smp_mb__after_clear_bit();
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| }
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| 
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| static inline int
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| nfs_defer_reschedule(struct nfs_page *req)
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| {
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| 	return !test_and_set_bit(PG_NEED_RESCHED, &req->wb_flags);
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| }
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| 
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| static inline void
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| nfs_clear_reschedule(struct nfs_page *req)
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| {
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| 	smp_mb__before_clear_bit();
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| 	clear_bit(PG_NEED_RESCHED, &req->wb_flags);
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| 	smp_mb__after_clear_bit();
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| }
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| 
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| static inline struct nfs_page *
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| nfs_list_entry(struct list_head *head)
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| {
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| 	return list_entry(head, struct nfs_page, wb_list);
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| }
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| 
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| static inline
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| loff_t req_offset(struct nfs_page *req)
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| {
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| 	return (((loff_t)req->wb_index) << PAGE_CACHE_SHIFT) + req->wb_offset;
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| }
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| 
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| #endif /* _LINUX_NFS_PAGE_H */
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