fs/nfs/pnfs.h - linux - Git at Google

 /*
  *  pNFS client data structures.
  *
  *  Copyright (c) 2002
  *  The Regents of the University of Michigan
  *  All Rights Reserved
  *
  *  Dean Hildebrand <dhildebz@umich.edu>
  *
  *  Permission is granted to use, copy, create derivative works, and
  *  redistribute this software and such derivative works for any purpose,
  *  so long as the name of the University of Michigan is not used in
  *  any advertising or publicity pertaining to the use or distribution
  *  of this software without specific, written prior authorization. If
  *  the above copyright notice or any other identification of the
  *  University of Michigan is included in any copy of any portion of
  *  this software, then the disclaimer below must also be included.
  *
  *  This software is provided as is, without representation or warranty
  *  of any kind either express or implied, including without limitation
  *  the implied warranties of merchantability, fitness for a particular
  *  purpose, or noninfringement.  The Regents of the University of
  *  Michigan shall not be liable for any damages, including special,
  *  indirect, incidental, or consequential damages, with respect to any
  *  claim arising out of or in connection with the use of the software,
  *  even if it has been or is hereafter advised of the possibility of
  *  such damages.
  */

 #ifndef FS_NFS_PNFS_H
 #define FS_NFS_PNFS_H

 #include <linux/nfs_page.h>

 enum {
 	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
 	NFS_LSEG_ROC,		/* roc bit received from server */
 };

 struct pnfs_layout_segment {
 	struct list_head pls_list;
 	struct pnfs_layout_range pls_range;
 	atomic_t pls_refcount;
 	unsigned long pls_flags;
 	struct pnfs_layout_hdr *pls_layout;
 };

 enum pnfs_try_status {
 	PNFS_ATTEMPTED     = 0,
 	PNFS_NOT_ATTEMPTED = 1,
 };

 #ifdef CONFIG_NFS_V4_1

 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"

 enum {
 	NFS_LAYOUT_RO_FAILED = 0,	/* get ro layout failed stop trying */
 	NFS_LAYOUT_RW_FAILED,		/* get rw layout failed stop trying */
 	NFS_LAYOUT_BULK_RECALL,		/* bulk recall affecting layout */
 	NFS_LAYOUT_ROC,			/* some lseg had roc bit set */
 	NFS_LAYOUT_DESTROYED,		/* no new use of layout allowed */
 };

 /* Per-layout driver specific registration structure */
 struct pnfs_layoutdriver_type {
 	struct list_head pnfs_tblid;
 	const u32 id;
 	const char *name;
 	struct module *owner;
 	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr);
 	void (*free_lseg) (struct pnfs_layout_segment *lseg);

 	/* test for nfs page cache coalescing */
 	int (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);

 	/*
 	 * Return PNFS_ATTEMPTED to indicate the layout code has attempted
 	 * I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
 	 */
 	enum pnfs_try_status (*read_pagelist) (struct nfs_read_data *nfs_data);
 };

 struct pnfs_layout_hdr {
 	atomic_t		plh_refcount;
 	struct list_head	plh_layouts;   /* other client layouts */
 	struct list_head	plh_bulk_recall; /* clnt list of bulk recalls */
 	struct list_head	plh_segs;      /* layout segments list */
 	nfs4_stateid		plh_stateid;
 	atomic_t		plh_outstanding; /* number of RPCs out */
 	unsigned long		plh_block_lgets; /* block LAYOUTGET if >0 */
 	u32			plh_barrier; /* ignore lower seqids */
 	unsigned long		plh_flags;
 	struct inode		*plh_inode;
 };

 struct pnfs_device {
 	struct nfs4_deviceid dev_id;
 	unsigned int  layout_type;
 	unsigned int  mincount;
 	struct page **pages;
 	void          *area;
 	unsigned int  pgbase;
 	unsigned int  pglen;
 };

 extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
 extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);

 /* nfs4proc.c */
 extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
 				   struct pnfs_device *dev);
 extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);

 /* pnfs.c */
 void get_layout_hdr(struct pnfs_layout_hdr *lo);
 void put_lseg(struct pnfs_layout_segment *lseg);
 struct pnfs_layout_segment *
 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 		   enum pnfs_iomode access_type);
 void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
 void unset_pnfs_layoutdriver(struct nfs_server *);
 enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
 					    const struct rpc_call_ops *);
 void pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *);
 void pnfs_pageio_init_write(struct nfs_pageio_descriptor *, struct inode *);
 int pnfs_layout_process(struct nfs4_layoutget *lgp);
 void pnfs_free_lseg_list(struct list_head *tmp_list);
 void pnfs_destroy_layout(struct nfs_inode *);
 void pnfs_destroy_all_layouts(struct nfs_client *);
 void put_layout_hdr(struct pnfs_layout_hdr *lo);
 void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
 			     const nfs4_stateid *new,
 			     bool update_barrier);
 int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
 				  struct pnfs_layout_hdr *lo,
 				  struct nfs4_state *open_state);
 int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 				struct list_head *tmp_list,
 				u32 iomode);
 bool pnfs_roc(struct inode *ino);
 void pnfs_roc_release(struct inode *ino);
 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
 bool pnfs_roc_drain(struct inode *ino, u32 *barrier);


 static inline int lo_fail_bit(u32 iomode)
 {
 	return iomode == IOMODE_RW ?
 			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 }

 static inline struct pnfs_layout_segment *
 get_lseg(struct pnfs_layout_segment *lseg)
 {
 	if (lseg) {
 		atomic_inc(&lseg->pls_refcount);
 		smp_mb__after_atomic_inc();
 	}
 	return lseg;
 }

 /* Return true if a layout driver is being used for this mountpoint */
 static inline int pnfs_enabled_sb(struct nfs_server *nfss)
 {
 	return nfss->pnfs_curr_ld != NULL;
 }

 #else  /* CONFIG_NFS_V4_1 */

 static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
 {
 }

 static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
 {
 }

 static inline struct pnfs_layout_segment *
 get_lseg(struct pnfs_layout_segment *lseg)
 {
 	return NULL;
 }

 static inline void put_lseg(struct pnfs_layout_segment *lseg)
 {
 }

 static inline struct pnfs_layout_segment *
 pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
 		   enum pnfs_iomode access_type)
 {
 	return NULL;
 }

 static inline enum pnfs_try_status
 pnfs_try_to_read_data(struct nfs_read_data *data,
 		      const struct rpc_call_ops *call_ops)
 {
 	return PNFS_NOT_ATTEMPTED;
 }

 static inline bool
 pnfs_roc(struct inode *ino)
 {
 	return false;
 }

 static inline void
 pnfs_roc_release(struct inode *ino)
 {
 }

 static inline void
 pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
 {
 }

 static inline bool
 pnfs_roc_drain(struct inode *ino, u32 *barrier)
 {
 	return false;
 }

 static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
 {
 }

 static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
 {
 }

 static inline void
 pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *ino)
 {
 	pgio->pg_test = NULL;
 }

 static inline void
 pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *ino)
 {
 	pgio->pg_test = NULL;
 }

 #endif /* CONFIG_NFS_V4_1 */

 #endif /* FS_NFS_PNFS_H */
	/*
	* pNFS client data structures.
	*
	* Copyright (c) 2002
	* The Regents of the University of Michigan
	* All Rights Reserved
	*
	* Dean Hildebrand <dhildebz@umich.edu>
	*
	* Permission is granted to use, copy, create derivative works, and
	* redistribute this software and such derivative works for any purpose,
	* so long as the name of the University of Michigan is not used in
	* any advertising or publicity pertaining to the use or distribution
	* of this software without specific, written prior authorization. If
	* the above copyright notice or any other identification of the
	* University of Michigan is included in any copy of any portion of
	* this software, then the disclaimer below must also be included.
	*
	* This software is provided as is, without representation or warranty
	* of any kind either express or implied, including without limitation
	* the implied warranties of merchantability, fitness for a particular
	* purpose, or noninfringement. The Regents of the University of
	* Michigan shall not be liable for any damages, including special,
	* indirect, incidental, or consequential damages, with respect to any
	* claim arising out of or in connection with the use of the software,
	* even if it has been or is hereafter advised of the possibility of
	* such damages.
	*/

	#ifndef FS_NFS_PNFS_H
	#define FS_NFS_PNFS_H

	#include <linux/nfs_page.h>

	enum {
	NFS_LSEG_VALID = 0, /* cleared when lseg is recalled/returned */
	NFS_LSEG_ROC, /* roc bit received from server */
	};

	struct pnfs_layout_segment {
	struct list_head pls_list;
	struct pnfs_layout_range pls_range;
	atomic_t pls_refcount;
	unsigned long pls_flags;
	struct pnfs_layout_hdr *pls_layout;
	};

	enum pnfs_try_status {
	PNFS_ATTEMPTED = 0,
	PNFS_NOT_ATTEMPTED = 1,
	};

	#ifdef CONFIG_NFS_V4_1

	#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"

	enum {
	NFS_LAYOUT_RO_FAILED = 0, /* get ro layout failed stop trying */
	NFS_LAYOUT_RW_FAILED, /* get rw layout failed stop trying */
	NFS_LAYOUT_BULK_RECALL, /* bulk recall affecting layout */
	NFS_LAYOUT_ROC, /* some lseg had roc bit set */
	NFS_LAYOUT_DESTROYED, /* no new use of layout allowed */
	};

	/* Per-layout driver specific registration structure */
	struct pnfs_layoutdriver_type {
	struct list_head pnfs_tblid;
	const u32 id;
	const char *name;
	struct module *owner;
	struct pnfs_layout_segment * (alloc_lseg) (struct pnfs_layout_hdr layoutid, struct nfs4_layoutget_res *lgr);
	void (free_lseg) (struct pnfs_layout_segment lseg);

	/* test for nfs page cache coalescing */
	int (pg_test)(struct nfs_pageio_descriptor , struct nfs_page , struct nfs_page );

	/*
	* Return PNFS_ATTEMPTED to indicate the layout code has attempted
	* I/O, else return PNFS_NOT_ATTEMPTED to fall back to normal NFS
	*/
	enum pnfs_try_status (read_pagelist) (struct nfs_read_data nfs_data);
	};

	struct pnfs_layout_hdr {
	atomic_t plh_refcount;
	struct list_head plh_layouts; /* other client layouts */
	struct list_head plh_bulk_recall; /* clnt list of bulk recalls */
	struct list_head plh_segs; /* layout segments list */
	nfs4_stateid plh_stateid;
	atomic_t plh_outstanding; /* number of RPCs out */
	unsigned long plh_block_lgets; /* block LAYOUTGET if >0 */
	u32 plh_barrier; /* ignore lower seqids */
	unsigned long plh_flags;
	struct inode *plh_inode;
	};

	struct pnfs_device {
	struct nfs4_deviceid dev_id;
	unsigned int layout_type;
	unsigned int mincount;
	struct page **pages;
	void *area;
	unsigned int pgbase;
	unsigned int pglen;
	};

	extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
	extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);

	/* nfs4proc.c */
	extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
	struct pnfs_device *dev);
	extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);

	/* pnfs.c */
	void get_layout_hdr(struct pnfs_layout_hdr *lo);
	void put_lseg(struct pnfs_layout_segment *lseg);
	struct pnfs_layout_segment *
	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	enum pnfs_iomode access_type);
	void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
	void unset_pnfs_layoutdriver(struct nfs_server *);
	enum pnfs_try_status pnfs_try_to_read_data(struct nfs_read_data *,
	const struct rpc_call_ops *);
	void pnfs_pageio_init_read(struct nfs_pageio_descriptor , struct inode );
	void pnfs_pageio_init_write(struct nfs_pageio_descriptor , struct inode );
	int pnfs_layout_process(struct nfs4_layoutget *lgp);
	void pnfs_free_lseg_list(struct list_head *tmp_list);
	void pnfs_destroy_layout(struct nfs_inode *);
	void pnfs_destroy_all_layouts(struct nfs_client *);
	void put_layout_hdr(struct pnfs_layout_hdr *lo);
	void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
	const nfs4_stateid *new,
	bool update_barrier);
	int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
	struct pnfs_layout_hdr *lo,
	struct nfs4_state *open_state);
	int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
	struct list_head *tmp_list,
	u32 iomode);
	bool pnfs_roc(struct inode *ino);
	void pnfs_roc_release(struct inode *ino);
	void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
	bool pnfs_roc_drain(struct inode ino, u32 barrier);


	static inline int lo_fail_bit(u32 iomode)
	{
	return iomode == IOMODE_RW ?
	NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
	}

	static inline struct pnfs_layout_segment *
	get_lseg(struct pnfs_layout_segment *lseg)
	{
	if (lseg) {
	atomic_inc(&lseg->pls_refcount);
	smp_mb__after_atomic_inc();
	}
	return lseg;
	}

	/* Return true if a layout driver is being used for this mountpoint */
	static inline int pnfs_enabled_sb(struct nfs_server *nfss)
	{
	return nfss->pnfs_curr_ld != NULL;
	}

	#else /* CONFIG_NFS_V4_1 */

	static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
	{
	}

	static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
	{
	}

	static inline struct pnfs_layout_segment *
	get_lseg(struct pnfs_layout_segment *lseg)
	{
	return NULL;
	}

	static inline void put_lseg(struct pnfs_layout_segment *lseg)
	{
	}

	static inline struct pnfs_layout_segment *
	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	enum pnfs_iomode access_type)
	{
	return NULL;
	}

	static inline enum pnfs_try_status
	pnfs_try_to_read_data(struct nfs_read_data *data,
	const struct rpc_call_ops *call_ops)
	{
	return PNFS_NOT_ATTEMPTED;
	}

	static inline bool
	pnfs_roc(struct inode *ino)
	{
	return false;
	}

	static inline void
	pnfs_roc_release(struct inode *ino)
	{
	}

	static inline void
	pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
	{
	}

	static inline bool
	pnfs_roc_drain(struct inode ino, u32 barrier)
	{
	return false;
	}

	static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
	{
	}

	static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
	{
	}

	static inline void
	pnfs_pageio_init_read(struct nfs_pageio_descriptor pgio, struct inode ino)
	{
	pgio->pg_test = NULL;
	}

	static inline void
	pnfs_pageio_init_write(struct nfs_pageio_descriptor pgio, struct inode ino)
	{
	pgio->pg_test = NULL;
	}

	#endif /* CONFIG_NFS_V4_1 */

	#endif /* FS_NFS_PNFS_H */