fs/nfs/delegation.h

   1 /*
   2  * linux/fs/nfs/delegation.h
   3  *
   4  * Copyright (c) Trond Myklebust
   5  *
   6  * Definitions pertaining to NFS delegated files
   7  */
   8 #ifndef FS_NFS_DELEGATION_H
   9 #define FS_NFS_DELEGATION_H
  10
  11 #if defined(CONFIG_NFS_V4)
  12 /*
  13  * NFSv4 delegation
  14  */
  15 struct nfs_delegation {
  16         struct list_head super_list;
  17         struct rpc_cred *cred;
  18         struct inode *inode;
  19         nfs4_stateid stateid;
  20         int type;
  21         loff_t maxsize;
  22         __u64 change_attr;
  23         unsigned long flags;
  24         spinlock_t lock;
  25         struct rcu_head rcu;
  26 };
  27
  28 enum {
  29         NFS_DELEGATION_NEED_RECLAIM = 0,
  30         NFS_DELEGATION_RETURN,
  31 };
  32
  33 int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res);
  34 void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res);
  35 int nfs_inode_return_delegation(struct inode *inode);
  36 int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid);
  37 void nfs_inode_return_delegation_noreclaim(struct inode *inode);
  38
  39 struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs_fh *fhandle);
  40 void nfs_super_return_all_delegations(struct super_block *sb);
  41 void nfs_expire_all_delegations(struct nfs_client *clp);
  42 void nfs_handle_cb_pathdown(struct nfs_client *clp);
  43
  44 void nfs_delegation_mark_reclaim(struct nfs_client *clp);
  45 void nfs_delegation_reap_unclaimed(struct nfs_client *clp);
  46
  47 /* NFSv4 delegation-related procedures */
  48 int nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, const nfs4_stateid *stateid, int issync);
  49 int nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs4_state *state, const nfs4_stateid *stateid);
  50 int nfs4_lock_delegation_recall(struct nfs4_state *state, struct file_lock *fl);
  51 int nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode);
  52
  53 static inline int nfs_have_delegation(struct inode *inode, int flags)
  54 {
  55         struct nfs_delegation *delegation;
  56         int ret = 0;
  57
  58         flags &= FMODE_READ|FMODE_WRITE;
  59         rcu_read_lock();
  60         delegation = rcu_dereference(NFS_I(inode)->delegation);
  61         if (delegation != NULL && (delegation->type & flags) == flags)
  62                 ret = 1;
  63         rcu_read_unlock();
  64         return ret;
  65 }
  66
  67 #else
  68 static inline int nfs_have_delegation(struct inode *inode, int flags)
  69 {
  70         return 0;
  71 }
  72
  73 static inline int nfs_inode_return_delegation(struct inode *inode)
  74 {
  75         return 0;
  76 }
  77 #endif
  78
  79 #endif