[mirror_ubuntu-artful-kernel.git] / 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

enum {
	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
};

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;
};

#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_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;
	int (*set_layoutdriver) (struct nfs_server *);
	int (*clear_layoutdriver) (struct nfs_server *);
	struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr);
	void (*free_lseg) (struct pnfs_layout_segment *lseg);
};

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 */
	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;
};

/*
 * Device ID RCU cache. A device ID is unique per client ID and layout type.
 */
#define NFS4_DEVICE_ID_HASH_BITS	5
#define NFS4_DEVICE_ID_HASH_SIZE	(1 << NFS4_DEVICE_ID_HASH_BITS)
#define NFS4_DEVICE_ID_HASH_MASK	(NFS4_DEVICE_ID_HASH_SIZE - 1)

static inline u32
nfs4_deviceid_hash(struct nfs4_deviceid *id)
{
	unsigned char *cptr = (unsigned char *)id->data;
	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
	u32 x = 0;

	while (nbytes--) {
		x *= 37;
		x += *cptr++;
	}
	return x & NFS4_DEVICE_ID_HASH_MASK;
}

struct pnfs_deviceid_node {
	struct hlist_node	de_node;
	struct nfs4_deviceid	de_id;
	atomic_t		de_ref;
};

struct pnfs_deviceid_cache {
	spinlock_t		dc_lock;
	atomic_t		dc_ref;
	void			(*dc_free_callback)(struct pnfs_deviceid_node *);
	struct hlist_head	dc_deviceids[NFS4_DEVICE_ID_HASH_SIZE];
};

extern int pnfs_alloc_init_deviceid_cache(struct nfs_client *,
			void (*free_callback)(struct pnfs_deviceid_node *));
extern void pnfs_put_deviceid_cache(struct nfs_client *);
extern struct pnfs_deviceid_node *pnfs_find_get_deviceid(
				struct pnfs_deviceid_cache *,
				struct nfs4_deviceid *);
extern struct pnfs_deviceid_node *pnfs_add_deviceid(
				struct pnfs_deviceid_cache *,
				struct pnfs_deviceid_node *);
extern void pnfs_put_deviceid(struct pnfs_deviceid_cache *c,
			      struct pnfs_deviceid_node *devid);

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);
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 *);
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);


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

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

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

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

#endif /* CONFIG_NFS_V4_1 */

#endif /* FS_NFS_PNFS_H */
Commit	Line	Data
85e174ba RL	1	/*
	2	* pNFS client data structures.
	3	*
	4	* Copyright (c) 2002
	5	* The Regents of the University of Michigan
	6	* All Rights Reserved
	7	*
	8	* Dean Hildebrand <dhildebz@umich.edu>
	9	*
	10	* Permission is granted to use, copy, create derivative works, and
	11	* redistribute this software and such derivative works for any purpose,
	12	* so long as the name of the University of Michigan is not used in
	13	* any advertising or publicity pertaining to the use or distribution
	14	* of this software without specific, written prior authorization. If
	15	* the above copyright notice or any other identification of the
	16	* University of Michigan is included in any copy of any portion of
	17	* this software, then the disclaimer below must also be included.
	18	*
	19	* This software is provided as is, without representation or warranty
	20	* of any kind either express or implied, including without limitation
	21	* the implied warranties of merchantability, fitness for a particular
	22	* purpose, or noninfringement. The Regents of the University of
	23	* Michigan shall not be liable for any damages, including special,
	24	* indirect, incidental, or consequential damages, with respect to any
	25	* claim arising out of or in connection with the use of the software,
	26	* even if it has been or is hereafter advised of the possibility of
	27	* such damages.
	28	*/
	29
	30	#ifndef FS_NFS_PNFS_H
	31	#define FS_NFS_PNFS_H
	32
4541d16c FI	33	enum {
	34	NFS_LSEG_VALID = 0, /* cleared when lseg is recalled/returned */
	35	};
	36
974cec8c	37	struct pnfs_layout_segment {
566052c5 FI	38	struct list_head pls_list;
566052c5 FI	39	struct pnfs_layout_range pls_range;
4541d16c FI	40	atomic_t pls_refcount;
4541d16c FI	41	unsigned long pls_flags;
566052c5	42	struct pnfs_layout_hdr *pls_layout;
974cec8c AA	43	};
974cec8c AA	44
85e174ba RL	45	#ifdef CONFIG_NFS_V4_1
	46
	47	#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
	48
e5e94017 BH	49	enum {
	50	NFS_LAYOUT_RO_FAILED = 0, /* get ro layout failed stop trying */
	51	NFS_LAYOUT_RW_FAILED, /* get rw layout failed stop trying */
43f1b3da	52	NFS_LAYOUT_BULK_RECALL, /* bulk recall affecting layout */
4541d16c	53	NFS_LAYOUT_DESTROYED, /* no new use of layout allowed */
e5e94017 BH	54	};
e5e94017 BH	55
85e174ba RL	56	/* Per-layout driver specific registration structure */
85e174ba RL	57	struct pnfs_layoutdriver_type {
02c35fca FI	58	struct list_head pnfs_tblid;
	59	const u32 id;
	60	const char *name;
	61	struct module *owner;
1c787096 TM	62	int (set_layoutdriver) (struct nfs_server );
1c787096 TM	63	int (clear_layoutdriver) (struct nfs_server );
b1f69b75 AA	64	struct pnfs_layout_segment * (alloc_lseg) (struct pnfs_layout_hdr layoutid, struct nfs4_layoutget_res *lgr);
b1f69b75 AA	65	void (free_lseg) (struct pnfs_layout_segment lseg);
85e174ba RL	66	};
85e174ba RL	67
e5e94017	68	struct pnfs_layout_hdr {
cc6e5340	69	atomic_t plh_refcount;
b7edfaa1	70	struct list_head plh_layouts; /* other client layouts */
43f1b3da	71	struct list_head plh_bulk_recall; /* clnt list of bulk recalls */
b7edfaa1	72	struct list_head plh_segs; /* layout segments list */
b7edfaa1	73	nfs4_stateid plh_stateid;
cf7d63f1	74	atomic_t plh_outstanding; /* number of RPCs out */
43f1b3da	75	u32 plh_barrier; /* ignore lower seqids */
566052c5	76	unsigned long plh_flags;
b7edfaa1	77	struct inode *plh_inode;
e5e94017 BH	78	};
e5e94017 BH	79
b1f69b75 AA	80	struct pnfs_device {
	81	struct nfs4_deviceid dev_id;
	82	unsigned int layout_type;
	83	unsigned int mincount;
	84	struct page **pages;
	85	void *area;
	86	unsigned int pgbase;
	87	unsigned int pglen;
	88	};
	89
	90	/*
	91	* Device ID RCU cache. A device ID is unique per client ID and layout type.
	92	*/
	93	#define NFS4_DEVICE_ID_HASH_BITS 5
	94	#define NFS4_DEVICE_ID_HASH_SIZE (1 << NFS4_DEVICE_ID_HASH_BITS)
	95	#define NFS4_DEVICE_ID_HASH_MASK (NFS4_DEVICE_ID_HASH_SIZE - 1)
	96
	97	static inline u32
	98	nfs4_deviceid_hash(struct nfs4_deviceid *id)
	99	{
	100	unsigned char cptr = (unsigned char )id->data;
	101	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
	102	u32 x = 0;
	103
	104	while (nbytes--) {
	105	x *= 37;
	106	x += *cptr++;
	107	}
	108	return x & NFS4_DEVICE_ID_HASH_MASK;
	109	}
	110
	111	struct pnfs_deviceid_node {
	112	struct hlist_node de_node;
	113	struct nfs4_deviceid de_id;
	114	atomic_t de_ref;
	115	};
	116
	117	struct pnfs_deviceid_cache {
	118	spinlock_t dc_lock;
	119	atomic_t dc_ref;
	120	void (dc_free_callback)(struct pnfs_deviceid_node );
	121	struct hlist_head dc_deviceids[NFS4_DEVICE_ID_HASH_SIZE];
	122	};
	123
	124	extern int pnfs_alloc_init_deviceid_cache(struct nfs_client *,
	125	void (free_callback)(struct pnfs_deviceid_node ));
	126	extern void pnfs_put_deviceid_cache(struct nfs_client *);
	127	extern struct pnfs_deviceid_node *pnfs_find_get_deviceid(
	128	struct pnfs_deviceid_cache *,
	129	struct nfs4_deviceid *);
	130	extern struct pnfs_deviceid_node *pnfs_add_deviceid(
	131	struct pnfs_deviceid_cache *,
	132	struct pnfs_deviceid_node *);
	133	extern void pnfs_put_deviceid(struct pnfs_deviceid_cache *c,
	134	struct pnfs_deviceid_node *devid);
	135
02c35fca FI	136	extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
	137	extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
	138
b1f69b75 AA	139	/* nfs4proc.c */
	140	extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
	141	struct pnfs_device *dev);
	142	extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
	143
	144	/* pnfs.c */
43f1b3da	145	void get_layout_hdr(struct pnfs_layout_hdr *lo);
e5e94017 BH	146	struct pnfs_layout_segment *
	147	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	148	enum pnfs_iomode access_type);
85e174ba RL	149	void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
85e174ba RL	150	void unset_pnfs_layoutdriver(struct nfs_server *);
b1f69b75	151	int pnfs_layout_process(struct nfs4_layoutget *lgp);
43f1b3da	152	void pnfs_free_lseg_list(struct list_head *tmp_list);
e5e94017	153	void pnfs_destroy_layout(struct nfs_inode *);
974cec8c	154	void pnfs_destroy_all_layouts(struct nfs_client *);
cc6e5340	155	void put_layout_hdr(struct pnfs_layout_hdr *lo);
43f1b3da FI	156	void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
	157	const nfs4_stateid *new,
	158	bool update_barrier);
fd6002e9 FI	159	int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
	160	struct pnfs_layout_hdr *lo,
	161	struct nfs4_state *open_state);
43f1b3da FI	162	int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
	163	struct list_head *tmp_list,
	164	u32 iomode);
e5e94017 BH	165
	166
	167	static inline int lo_fail_bit(u32 iomode)
	168	{
	169	return iomode == IOMODE_RW ?
	170	NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
	171	}
	172
	173	/* Return true if a layout driver is being used for this mountpoint */
	174	static inline int pnfs_enabled_sb(struct nfs_server *nfss)
	175	{
	176	return nfss->pnfs_curr_ld != NULL;
	177	}
85e174ba RL	178
	179	#else /* CONFIG_NFS_V4_1 */
	180
974cec8c AA	181	static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
	182	{
	183	}
	184
e5e94017 BH	185	static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
	186	{
	187	}
	188
	189	static inline struct pnfs_layout_segment *
	190	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	191	enum pnfs_iomode access_type)
	192	{
	193	return NULL;
	194	}
	195
85e174ba RL	196	static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
	197	{
	198	}
	199
	200	static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
	201	{
	202	}
	203
	204	#endif /* CONFIG_NFS_V4_1 */
	205
	206	#endif /* FS_NFS_PNFS_H */