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1#ifndef _FS_NFSD_FILECACHE_H
2#define _FS_NFSD_FILECACHE_H
3
4#include <linux/fsnotify_backend.h>
5
6/*
7 * Limit the time that the list_lru_one lock is held during
8 * an LRU scan.
9 */
10#define NFSD_FILE_GC_BATCH (16UL)
11
12/*
13 * This is the fsnotify_mark container that nfsd attaches to the files that it
14 * is holding open. Note that we have a separate refcount here aside from the
15 * one in the fsnotify_mark. We only want a single fsnotify_mark attached to
16 * the inode, and for each nfsd_file to hold a reference to it.
17 *
18 * The fsnotify_mark is itself refcounted, but that's not sufficient to tell us
19 * how to put that reference. If there are still outstanding nfsd_files that
20 * reference the mark, then we would want to call fsnotify_put_mark on it.
21 * If there were not, then we'd need to call fsnotify_destroy_mark. Since we
22 * can't really tell the difference, we use the nfm_mark to keep track of how
23 * many nfsd_files hold references to the mark. When that counter goes to zero
24 * then we know to call fsnotify_destroy_mark on it.
25 */
26struct nfsd_file_mark {
27 struct fsnotify_mark nfm_mark;
28 refcount_t nfm_ref;
29 /* serializes nfsd_fsnotify_recalc_mask() against itself */
30 struct mutex nfm_recalc_mutex;
31};
32
33/*
34 * A representation of a file that has been opened by knfsd. These are hashed
35 * in the hashtable by inode pointer value. Note that this object doesn't
36 * hold a reference to the inode by itself, so the nf_inode pointer should
37 * never be dereferenced, only used for comparison.
38 */
39struct nfsd_file {
40 struct rhlist_head nf_rlist;
41 void *nf_inode;
42 struct file *nf_file;
43 const struct cred *nf_cred;
44 struct net *nf_net;
45#define NFSD_FILE_HASHED (0)
46#define NFSD_FILE_PENDING (1)
47#define NFSD_FILE_REFERENCED (2)
48#define NFSD_FILE_GC (3)
49#define NFSD_FILE_RECENT (4)
50 unsigned long nf_flags;
51 refcount_t nf_ref;
52 unsigned char nf_may;
53
54 struct nfsd_file_mark *nf_mark;
55 struct list_head nf_lru;
56 struct list_head nf_gc;
57 struct rcu_head nf_rcu;
58 ktime_t nf_birthtime;
59
60 u32 nf_dio_mem_align;
61 u32 nf_dio_offset_align;
62 u32 nf_dio_read_offset_align;
63};
64
65int nfsd_file_cache_init(void);
66void nfsd_file_cache_purge(struct net *);
67void nfsd_file_cache_shutdown(void);
68int nfsd_file_cache_start_net(struct net *net);
69void nfsd_file_cache_shutdown_net(struct net *net);
70void nfsd_file_put(struct nfsd_file *nf);
71struct net *nfsd_file_put_local(struct nfsd_file __rcu **nf);
72struct nfsd_file *nfsd_file_get(struct nfsd_file *nf);
73struct file *nfsd_file_file(struct nfsd_file *nf);
74void nfsd_file_close_inode_sync(struct inode *inode);
75void nfsd_file_close_export(struct net *net, const struct path *path);
76void nfsd_file_net_dispose(struct nfsd_net *nn);
77bool nfsd_file_is_cached(struct inode *inode);
78__be32 nfsd_file_acquire_gc(struct svc_rqst *rqstp, struct svc_fh *fhp,
79 unsigned int may_flags, struct nfsd_file **nfp);
80__be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
81 unsigned int may_flags, struct nfsd_file **nfp);
82__be32 nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp,
83 unsigned int may_flags, struct file *file,
84 struct nfsd_file **nfp);
85__be32 nfsd_file_acquire_local(struct net *net, struct svc_cred *cred,
86 struct auth_domain *client, struct svc_fh *fhp,
87 unsigned int may_flags, struct nfsd_file **pnf);
88__be32 nfsd_file_acquire_dir(struct svc_rqst *rqstp, struct svc_fh *fhp,
89 struct nfsd_file **pnf);
90int nfsd_file_cache_stats_show(struct seq_file *m, void *v);
91void nfsd_fsnotify_recalc_mask(struct nfsd_file *nf);
92#endif /* _FS_NFSD_FILECACHE_H */