xref: /openbmc/linux/fs/nfsd/vfs.h (revision bb3982b4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
4  */
5 
6 #ifndef LINUX_NFSD_VFS_H
7 #define LINUX_NFSD_VFS_H
8 
9 #include "nfsfh.h"
10 #include "nfsd.h"
11 
12 /*
13  * Flags for nfsd_permission
14  */
15 #define NFSD_MAY_NOP			0
16 #define NFSD_MAY_EXEC			0x001 /* == MAY_EXEC */
17 #define NFSD_MAY_WRITE			0x002 /* == MAY_WRITE */
18 #define NFSD_MAY_READ			0x004 /* == MAY_READ */
19 #define NFSD_MAY_SATTR			0x008
20 #define NFSD_MAY_TRUNC			0x010
21 #define NFSD_MAY_LOCK			0x020
22 #define NFSD_MAY_MASK			0x03f
23 
24 /* extra hints to permission and open routines: */
25 #define NFSD_MAY_OWNER_OVERRIDE		0x040
26 #define NFSD_MAY_LOCAL_ACCESS		0x080 /* for device special files */
27 #define NFSD_MAY_BYPASS_GSS_ON_ROOT	0x100
28 #define NFSD_MAY_NOT_BREAK_LEASE	0x200
29 #define NFSD_MAY_BYPASS_GSS		0x400
30 #define NFSD_MAY_READ_IF_EXEC		0x800
31 
32 #define NFSD_MAY_64BIT_COOKIE		0x1000 /* 64 bit readdir cookies for >= NFSv3 */
33 
34 #define NFSD_MAY_CREATE		(NFSD_MAY_EXEC|NFSD_MAY_WRITE)
35 #define NFSD_MAY_REMOVE		(NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC)
36 
37 /*
38  * Callback function for readdir
39  */
40 typedef int (*nfsd_filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
41 
42 /* nfsd/vfs.c */
43 int		nfsd_racache_init(int);
44 void		nfsd_racache_shutdown(void);
45 int		nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
46 		                struct svc_export **expp);
47 __be32		nfsd_lookup(struct svc_rqst *, struct svc_fh *,
48 				const char *, unsigned int, struct svc_fh *);
49 __be32		 nfsd_lookup_dentry(struct svc_rqst *, struct svc_fh *,
50 				const char *, unsigned int,
51 				struct svc_export **, struct dentry **);
52 __be32		nfsd_setattr(struct svc_rqst *, struct svc_fh *,
53 				struct iattr *, int, time_t);
54 int nfsd_mountpoint(struct dentry *, struct svc_export *);
55 #ifdef CONFIG_NFSD_V4
56 __be32          nfsd4_set_nfs4_label(struct svc_rqst *, struct svc_fh *,
57 		    struct xdr_netobj *);
58 __be32		nfsd4_vfs_fallocate(struct svc_rqst *, struct svc_fh *,
59 				    struct file *, loff_t, loff_t, int);
60 __be32		nfsd4_clone_file_range(struct file *, u64, struct file *,
61 			u64, u64);
62 #endif /* CONFIG_NFSD_V4 */
63 __be32		nfsd_create_locked(struct svc_rqst *, struct svc_fh *,
64 				char *name, int len, struct iattr *attrs,
65 				int type, dev_t rdev, struct svc_fh *res);
66 __be32		nfsd_create(struct svc_rqst *, struct svc_fh *,
67 				char *name, int len, struct iattr *attrs,
68 				int type, dev_t rdev, struct svc_fh *res);
69 #ifdef CONFIG_NFSD_V3
70 __be32		nfsd_access(struct svc_rqst *, struct svc_fh *, u32 *, u32 *);
71 __be32		do_nfsd_create(struct svc_rqst *, struct svc_fh *,
72 				char *name, int len, struct iattr *attrs,
73 				struct svc_fh *res, int createmode,
74 				u32 *verifier, bool *truncp, bool *created);
75 __be32		nfsd_commit(struct svc_rqst *, struct svc_fh *,
76 				loff_t, unsigned long);
77 #endif /* CONFIG_NFSD_V3 */
78 __be32		nfsd_open(struct svc_rqst *, struct svc_fh *, umode_t,
79 				int, struct file **);
80 struct raparms;
81 __be32		nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
82 				struct file *file, loff_t offset,
83 				unsigned long *count);
84 __be32		nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
85 				struct file *file, loff_t offset,
86 				struct kvec *vec, int vlen,
87 				unsigned long *count);
88 __be32 		nfsd_read(struct svc_rqst *, struct svc_fh *,
89 				loff_t, struct kvec *, int, unsigned long *);
90 __be32 		nfsd_write(struct svc_rqst *, struct svc_fh *, loff_t,
91 				struct kvec *, int, unsigned long *, int);
92 __be32		nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp,
93 				struct file *file, loff_t offset,
94 				struct kvec *vec, int vlen, unsigned long *cnt,
95 				int stable);
96 __be32		nfsd_readlink(struct svc_rqst *, struct svc_fh *,
97 				char *, int *);
98 __be32		nfsd_symlink(struct svc_rqst *, struct svc_fh *,
99 				char *name, int len, char *path,
100 				struct svc_fh *res);
101 __be32		nfsd_link(struct svc_rqst *, struct svc_fh *,
102 				char *, int, struct svc_fh *);
103 ssize_t		nfsd_copy_file_range(struct file *, u64,
104 				     struct file *, u64, u64);
105 __be32		nfsd_rename(struct svc_rqst *,
106 				struct svc_fh *, char *, int,
107 				struct svc_fh *, char *, int);
108 __be32		nfsd_unlink(struct svc_rqst *, struct svc_fh *, int type,
109 				char *name, int len);
110 __be32		nfsd_readdir(struct svc_rqst *, struct svc_fh *,
111 			     loff_t *, struct readdir_cd *, nfsd_filldir_t);
112 __be32		nfsd_statfs(struct svc_rqst *, struct svc_fh *,
113 				struct kstatfs *, int access);
114 
115 __be32		nfsd_permission(struct svc_rqst *, struct svc_export *,
116 				struct dentry *, int);
117 
118 struct raparms *nfsd_init_raparms(struct file *file);
119 void		nfsd_put_raparams(struct file *file, struct raparms *ra);
120 
121 static inline int fh_want_write(struct svc_fh *fh)
122 {
123 	int ret;
124 
125 	if (fh->fh_want_write)
126 		return 0;
127 	ret = mnt_want_write(fh->fh_export->ex_path.mnt);
128 	if (!ret)
129 		fh->fh_want_write = true;
130 	return ret;
131 }
132 
133 static inline void fh_drop_write(struct svc_fh *fh)
134 {
135 	if (fh->fh_want_write) {
136 		fh->fh_want_write = false;
137 		mnt_drop_write(fh->fh_export->ex_path.mnt);
138 	}
139 }
140 
141 static inline __be32 fh_getattr(struct svc_fh *fh, struct kstat *stat)
142 {
143 	struct path p = {.mnt = fh->fh_export->ex_path.mnt,
144 			 .dentry = fh->fh_dentry};
145 	return nfserrno(vfs_getattr(&p, stat, STATX_BASIC_STATS,
146 				    AT_STATX_SYNC_AS_STAT));
147 }
148 
149 static inline int nfsd_create_is_exclusive(int createmode)
150 {
151 	return createmode == NFS3_CREATE_EXCLUSIVE
152 	       || createmode == NFS4_CREATE_EXCLUSIVE4_1;
153 }
154 
155 static inline bool nfsd_eof_on_read(long requested, long read,
156 				loff_t offset, loff_t size)
157 {
158 	/* We assume a short read means eof: */
159 	if (requested > read)
160 		return true;
161 	/*
162 	 * A non-short read might also reach end of file.  The spec
163 	 * still requires us to set eof in that case.
164 	 *
165 	 * Further operations may have modified the file size since
166 	 * the read, so the following check is not atomic with the read.
167 	 * We've only seen that cause a problem for a client in the case
168 	 * where the read returned a count of 0 without setting eof.
169 	 * That case was fixed by the addition of the above check.
170 	 */
171 	return (offset + read >= size);
172 }
173 
174 #endif /* LINUX_NFSD_VFS_H */
175