[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 */
	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;
};

#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;
	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 */
	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;
};

/*
 * 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);
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;
}

/* 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 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)
{
}

#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 {
4541d16c FI	34	NFS_LSEG_VALID = 0, /* cleared when lseg is recalled/returned */
f7e8917a	35	NFS_LSEG_ROC, /* roc bit received from server */
4541d16c FI	36	};
4541d16c FI	37
974cec8c	38	struct pnfs_layout_segment {
566052c5 FI	39	struct list_head pls_list;
566052c5 FI	40	struct pnfs_layout_range pls_range;
4541d16c FI	41	atomic_t pls_refcount;
4541d16c FI	42	unsigned long pls_flags;
566052c5	43	struct pnfs_layout_hdr *pls_layout;
974cec8c AA	44	};
974cec8c AA	45
85e174ba RL	46	#ifdef CONFIG_NFS_V4_1
	47
	48	#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
	49
e5e94017 BH	50	enum {
	51	NFS_LAYOUT_RO_FAILED = 0, /* get ro layout failed stop trying */
	52	NFS_LAYOUT_RW_FAILED, /* get rw layout failed stop trying */
43f1b3da	53	NFS_LAYOUT_BULK_RECALL, /* bulk recall affecting layout */
f7e8917a	54	NFS_LAYOUT_ROC, /* some lseg had roc bit set */
4541d16c	55	NFS_LAYOUT_DESTROYED, /* no new use of layout allowed */
e5e94017 BH	56	};
e5e94017 BH	57
85e174ba RL	58	/* Per-layout driver specific registration structure */
85e174ba RL	59	struct pnfs_layoutdriver_type {
02c35fca FI	60	struct list_head pnfs_tblid;
	61	const u32 id;
	62	const char *name;
	63	struct module *owner;
1c787096 TM	64	int (set_layoutdriver) (struct nfs_server );
1c787096 TM	65	int (clear_layoutdriver) (struct nfs_server );
b1f69b75 AA	66	struct pnfs_layout_segment * (alloc_lseg) (struct pnfs_layout_hdr layoutid, struct nfs4_layoutget_res *lgr);
b1f69b75 AA	67	void (free_lseg) (struct pnfs_layout_segment lseg);
85e174ba RL	68	};
85e174ba RL	69
e5e94017	70	struct pnfs_layout_hdr {
cc6e5340	71	atomic_t plh_refcount;
b7edfaa1	72	struct list_head plh_layouts; /* other client layouts */
43f1b3da	73	struct list_head plh_bulk_recall; /* clnt list of bulk recalls */
b7edfaa1	74	struct list_head plh_segs; /* layout segments list */
b7edfaa1	75	nfs4_stateid plh_stateid;
cf7d63f1	76	atomic_t plh_outstanding; /* number of RPCs out */
f7e8917a	77	unsigned long plh_block_lgets; /* block LAYOUTGET if >0 */
43f1b3da	78	u32 plh_barrier; /* ignore lower seqids */
566052c5	79	unsigned long plh_flags;
b7edfaa1	80	struct inode *plh_inode;
e5e94017 BH	81	};
e5e94017 BH	82
b1f69b75 AA	83	struct pnfs_device {
	84	struct nfs4_deviceid dev_id;
	85	unsigned int layout_type;
	86	unsigned int mincount;
	87	struct page **pages;
	88	void *area;
	89	unsigned int pgbase;
	90	unsigned int pglen;
	91	};
	92
	93	/*
	94	* Device ID RCU cache. A device ID is unique per client ID and layout type.
	95	*/
	96	#define NFS4_DEVICE_ID_HASH_BITS 5
	97	#define NFS4_DEVICE_ID_HASH_SIZE (1 << NFS4_DEVICE_ID_HASH_BITS)
	98	#define NFS4_DEVICE_ID_HASH_MASK (NFS4_DEVICE_ID_HASH_SIZE - 1)
	99
	100	static inline u32
	101	nfs4_deviceid_hash(struct nfs4_deviceid *id)
	102	{
	103	unsigned char cptr = (unsigned char )id->data;
	104	unsigned int nbytes = NFS4_DEVICEID4_SIZE;
	105	u32 x = 0;
	106
	107	while (nbytes--) {
	108	x *= 37;
	109	x += *cptr++;
	110	}
	111	return x & NFS4_DEVICE_ID_HASH_MASK;
	112	}
	113
	114	struct pnfs_deviceid_node {
	115	struct hlist_node de_node;
	116	struct nfs4_deviceid de_id;
	117	atomic_t de_ref;
	118	};
	119
	120	struct pnfs_deviceid_cache {
	121	spinlock_t dc_lock;
	122	atomic_t dc_ref;
	123	void (dc_free_callback)(struct pnfs_deviceid_node );
	124	struct hlist_head dc_deviceids[NFS4_DEVICE_ID_HASH_SIZE];
	125	};
	126
	127	extern int pnfs_alloc_init_deviceid_cache(struct nfs_client *,
	128	void (free_callback)(struct pnfs_deviceid_node ));
	129	extern void pnfs_put_deviceid_cache(struct nfs_client *);
	130	extern struct pnfs_deviceid_node *pnfs_find_get_deviceid(
	131	struct pnfs_deviceid_cache *,
	132	struct nfs4_deviceid *);
	133	extern struct pnfs_deviceid_node *pnfs_add_deviceid(
	134	struct pnfs_deviceid_cache *,
	135	struct pnfs_deviceid_node *);
	136	extern void pnfs_put_deviceid(struct pnfs_deviceid_cache *c,
	137	struct pnfs_deviceid_node *devid);
	138
02c35fca FI	139	extern int pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *);
	140	extern void pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *);
	141
b1f69b75 AA	142	/* nfs4proc.c */
	143	extern int nfs4_proc_getdeviceinfo(struct nfs_server *server,
	144	struct pnfs_device *dev);
	145	extern int nfs4_proc_layoutget(struct nfs4_layoutget *lgp);
	146
	147	/* pnfs.c */
43f1b3da	148	void get_layout_hdr(struct pnfs_layout_hdr *lo);
e5e94017 BH	149	struct pnfs_layout_segment *
	150	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	151	enum pnfs_iomode access_type);
85e174ba RL	152	void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
85e174ba RL	153	void unset_pnfs_layoutdriver(struct nfs_server *);
b1f69b75	154	int pnfs_layout_process(struct nfs4_layoutget *lgp);
43f1b3da	155	void pnfs_free_lseg_list(struct list_head *tmp_list);
e5e94017	156	void pnfs_destroy_layout(struct nfs_inode *);
974cec8c	157	void pnfs_destroy_all_layouts(struct nfs_client *);
cc6e5340	158	void put_layout_hdr(struct pnfs_layout_hdr *lo);
43f1b3da FI	159	void pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo,
	160	const nfs4_stateid *new,
	161	bool update_barrier);
fd6002e9 FI	162	int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
	163	struct pnfs_layout_hdr *lo,
	164	struct nfs4_state *open_state);
43f1b3da FI	165	int mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
	166	struct list_head *tmp_list,
	167	u32 iomode);
f7e8917a FI	168	bool pnfs_roc(struct inode *ino);
	169	void pnfs_roc_release(struct inode *ino);
	170	void pnfs_roc_set_barrier(struct inode *ino, u32 barrier);
	171	bool pnfs_roc_drain(struct inode ino, u32 barrier);
e5e94017 BH	172
	173
	174	static inline int lo_fail_bit(u32 iomode)
	175	{
	176	return iomode == IOMODE_RW ?
	177	NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
	178	}
	179
	180	/* Return true if a layout driver is being used for this mountpoint */
	181	static inline int pnfs_enabled_sb(struct nfs_server *nfss)
	182	{
	183	return nfss->pnfs_curr_ld != NULL;
	184	}
85e174ba RL	185
	186	#else /* CONFIG_NFS_V4_1 */
	187
974cec8c AA	188	static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)
	189	{
	190	}
	191
e5e94017 BH	192	static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)
	193	{
	194	}
	195
	196	static inline struct pnfs_layout_segment *
	197	pnfs_update_layout(struct inode ino, struct nfs_open_context ctx,
	198	enum pnfs_iomode access_type)
	199	{
	200	return NULL;
	201	}
	202
f7e8917a FI	203	static inline bool
	204	pnfs_roc(struct inode *ino)
	205	{
	206	return false;
	207	}
	208
	209	static inline void
	210	pnfs_roc_release(struct inode *ino)
	211	{
	212	}
	213
	214	static inline void
	215	pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
	216	{
	217	}
	218
	219	static inline bool
	220	pnfs_roc_drain(struct inode ino, u32 barrier)
	221	{
	222	return false;
	223	}
	224
85e174ba RL	225	static inline void set_pnfs_layoutdriver(struct nfs_server *s, u32 id)
	226	{
	227	}
	228
	229	static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
	230	{
	231	}
	232
	233	#endif /* CONFIG_NFS_V4_1 */
	234
	235	#endif /* FS_NFS_PNFS_H */