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Diffstat (limited to 'fs/nfs/pnfs.h')
| -rw-r--r-- | fs/nfs/pnfs.h | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h new file mode 100644 index 000000000000..e12367d50489 --- /dev/null +++ b/fs/nfs/pnfs.h @@ -0,0 +1,189 @@ +/* + * 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 + +struct pnfs_layout_segment { + struct list_head fi_list; + struct pnfs_layout_range range; + struct kref kref; + struct pnfs_layout_hdr *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_STATEID_SET, /* have a valid layout stateid */ +}; + +/* 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 { + unsigned long refcount; + struct list_head layouts; /* other client layouts */ + struct list_head segs; /* layout segments list */ + seqlock_t seqlock; /* Protects the stateid */ + nfs4_stateid stateid; + unsigned long state; + struct inode *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 */ +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_destroy_layout(struct nfs_inode *); +void pnfs_destroy_all_layouts(struct nfs_client *); +void put_layout_hdr(struct inode *inode); +void pnfs_get_layout_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo, + struct nfs4_state *open_state); + + +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 */ |