#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)
{
}