path: root/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/refcount.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_page.h>
#include <linux/workqueue.h>

struct nfs4_opendata;

enum {
	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
	NFS_LSEG_ROC,		/* roc bit received from server */
	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
	NFS_LSEG_LAYOUTRETURN,	/* layoutreturn bit set for layoutreturn */
	NFS_LSEG_UNAVAILABLE,	/* unavailable bit set for temporary problem */
};

/* Individual ip address */
struct nfs4_pnfs_ds_addr {
	struct sockaddr_storage	da_addr;
	size_t			da_addrlen;
	struct list_head	da_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
	char			*da_remotestr;	/* human readable addr+port */
	const char		*da_netid;
	int			da_transport;
};

struct nfs4_pnfs_ds {
	struct list_head	ds_node;  /* nfs4_pnfs_dev_hlist dev_dslist */
	char			*ds_remotestr;	/* comma sep list of addrs */
	struct list_head	ds_addrs;
	struct nfs_client	*ds_clp;
	refcount_t		ds_count;
	unsigned long		ds_state;
#define NFS4DS_CONNECTING	0	/* ds is establishing connection */
};

struct pnfs_layout_segment {
	struct list_head pls_list;
	struct list_head pls_lc_list;
	struct list_head pls_commits;
	struct pnfs_layout_range pls_range;
	refcount_t pls_refcount;
	u32 pls_seq;
	unsigned long pls_flags;
	struct pnfs_layout_hdr *pls_layout;
};

enum pnfs_try_status {
	PNFS_ATTEMPTED     = 0,
	PNFS_NOT_ATTEMPTED = 1,
	PNFS_TRY_AGAIN     = 2,
};

/* error codes for internal use */
#define NFS4ERR_RESET_TO_MDS   12001
#define NFS4ERR_RESET_TO_PNFS  12002

#ifdef CONFIG_NFS_V4_1

#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"

/*
 * Default data server connection timeout and retrans vaules.
 * Set by module parameters dataserver_timeo and dataserver_retrans.
 */
#define NFS4_DEF_DS_TIMEO   600 /* in tenths of a second */
#define NFS4_DEF_DS_RETRANS 5
#define PNFS_DEVICE_RETRY_TIMEOUT (120*HZ)

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_RETURN,		/* layoutreturn in progress */
	NFS_LAYOUT_RETURN_LOCK,		/* Serialise layoutreturn */
	NFS_LAYOUT_RETURN_REQUESTED,	/* Return this layout ASAP */
	NFS_LAYOUT_INVALID_STID,	/* layout stateid id is invalid */
	NFS_LAYOUT_FIRST_LAYOUTGET,	/* Serialize first layoutget */
	NFS_LAYOUT_INODE_FREEING,	/* The inode is being freed */
	NFS_LAYOUT_HASHED,		/* The layout visible */
};

enum layoutdriver_policy_flags {
	/* Should the pNFS client commit and return the layout upon truncate to
	 * a smaller size */
	PNFS_LAYOUTRET_ON_SETATTR	= 1 << 0,
	PNFS_LAYOUTRET_ON_ERROR		= 1 << 1,
	PNFS_READ_WHOLE_PAGE		= 1 << 2,
	PNFS_LAYOUTGET_ON_OPEN		= 1 << 3,
};

struct nfs4_deviceid_node;

/* Per-layout driver specific registration structure */
struct pnfs_layoutdriver_type {
	struct list_head pnfs_tblid;
	const u32 id;
	const char *name;
	struct module *owner;
	unsigned flags;
	unsigned max_deviceinfo_size;
	unsigned max_layoutget_response;

	int (*set_layoutdriver) (struct nfs_server *, const struct nfs_fh *);
	int (*clear_layoutdriver) (struct nfs_server *);

	struct pnfs_layout_hdr * (*alloc_layout_hdr) (struct inode *inode, gfp_t gfp_flags);
	void (*free_layout_hdr) (struct pnfs_layout_hdr *);

	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr, gfp_t gfp_flags);
	void (*free_lseg) (struct pnfs_layout_segment *lseg);
	void (*add_lseg) (struct pnfs_layout_hdr *layoutid,
			struct pnfs_layout_segment *lseg,
			struct list_head *free_me);

	void (*return_range) (struct pnfs_layout_hdr *lo,
			      struct pnfs_layout_range *range);

	/* test for nfs page cache coalescing */
	const struct nfs_pageio_ops *pg_read_ops;
	const struct nfs_pageio_ops *pg_write_ops;

	struct pnfs_ds_commit_info *(*get_ds_info) (struct inode *inode);

	int (*sync)(struct inode *inode, bool datasync);

	/*
	 * 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_pgio_header *);
	enum pnfs_try_status (*write_pagelist)(struct nfs_pgio_header *, int);

	void (*free_deviceid_node) (struct nfs4_deviceid_node *);
	struct nfs4_deviceid_node * (*alloc_deviceid_node)
			(struct nfs_server *server, struct pnfs_device *pdev,
			gfp_t gfp_flags);

	int (*prepare_layoutreturn) (struct nfs4_layoutreturn_args *);

	void (*cleanup_layoutcommit) (struct nfs4_layoutcommit_data *data);
	int (*prepare_layoutcommit) (struct nfs4_layoutcommit_args *args);
	int (*prepare_layoutstats) (struct nfs42_layoutstat_args *args);
};

struct pnfs_commit_ops