1 #ifndef _FS_NFSD_FILECACHE_H 2 #define _FS_NFSD_FILECACHE_H 3 4 #include <linux/fsnotify_backend.h> 5 6 /* 7 * This is the fsnotify_mark container that nfsd attaches to the files that it 8 * is holding open. Note that we have a separate refcount here aside from the 9 * one in the fsnotify_mark. We only want a single fsnotify_mark attached to 10 * the inode, and for each nfsd_file to hold a reference to it. 11 * 12 * The fsnotify_mark is itself refcounted, but that's not sufficient to tell us 13 * how to put that reference. If there are still outstanding nfsd_files that 14 * reference the mark, then we would want to call fsnotify_put_mark on it. 15 * If there were not, then we'd need to call fsnotify_destroy_mark. Since we 16 * can't really tell the difference, we use the nfm_mark to keep track of how 17 * many nfsd_files hold references to the mark. When that counter goes to zero 18 * then we know to call fsnotify_destroy_mark on it. 19 */ 20 struct nfsd_file_mark { 21 struct fsnotify_mark nfm_mark; 22 atomic_t nfm_ref; 23 }; 24 25 /* 26 * A representation of a file that has been opened by knfsd. These are hashed 27 * in the hashtable by inode pointer value. Note that this object doesn't 28 * hold a reference to the inode by itself, so the nf_inode pointer should 29 * never be dereferenced, only used for comparison. 30 */ 31 struct nfsd_file { 32 struct hlist_node nf_node; 33 struct list_head nf_lru; 34 struct rcu_head nf_rcu; 35 struct file *nf_file; 36 const struct cred *nf_cred; 37 struct net *nf_net; 38 #define NFSD_FILE_HASHED (0) 39 #define NFSD_FILE_PENDING (1) 40 #define NFSD_FILE_BREAK_READ (2) 41 #define NFSD_FILE_BREAK_WRITE (3) 42 #define NFSD_FILE_REFERENCED (4) 43 unsigned long nf_flags; 44 struct inode *nf_inode; 45 unsigned int nf_hashval; 46 atomic_t nf_ref; 47 unsigned char nf_may; 48 struct nfsd_file_mark *nf_mark; 49 }; 50 51 int nfsd_file_cache_init(void); 52 void nfsd_file_cache_purge(struct net *); 53 void nfsd_file_cache_shutdown(void); 54 void nfsd_file_put(struct nfsd_file *nf); 55 struct nfsd_file *nfsd_file_get(struct nfsd_file *nf); 56 void nfsd_file_close_inode_sync(struct inode *inode); 57 bool nfsd_file_is_cached(struct inode *inode); 58 __be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, 59 unsigned int may_flags, struct nfsd_file **nfp); 60 int nfsd_file_cache_stats_open(struct inode *, struct file *); 61 #endif /* _FS_NFSD_FILECACHE_H */ 62