xref: /linux/fs/nfsd/nfsfh.h (revision f884ab15afdc5514e88105c92a4e2e1e6539869a)
1 /* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> */
2 
3 #ifndef _LINUX_NFSD_FH_INT_H
4 #define _LINUX_NFSD_FH_INT_H
5 
6 #include <linux/nfsd/nfsfh.h>
7 
8 enum nfsd_fsid {
9 	FSID_DEV = 0,
10 	FSID_NUM,
11 	FSID_MAJOR_MINOR,
12 	FSID_ENCODE_DEV,
13 	FSID_UUID4_INUM,
14 	FSID_UUID8,
15 	FSID_UUID16,
16 	FSID_UUID16_INUM,
17 };
18 
19 enum fsid_source {
20 	FSIDSOURCE_DEV,
21 	FSIDSOURCE_FSID,
22 	FSIDSOURCE_UUID,
23 };
24 extern enum fsid_source fsid_source(struct svc_fh *fhp);
25 
26 
27 /* This might look a little large to "inline" but in all calls except
28  * one, 'vers' is constant so moste of the function disappears.
29  */
30 static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
31 			   u32 fsid, unsigned char *uuid)
32 {
33 	u32 *up;
34 	switch(vers) {
35 	case FSID_DEV:
36 		fsidv[0] = htonl((MAJOR(dev)<<16) |
37 				 MINOR(dev));
38 		fsidv[1] = ino_t_to_u32(ino);
39 		break;
40 	case FSID_NUM:
41 		fsidv[0] = fsid;
42 		break;
43 	case FSID_MAJOR_MINOR:
44 		fsidv[0] = htonl(MAJOR(dev));
45 		fsidv[1] = htonl(MINOR(dev));
46 		fsidv[2] = ino_t_to_u32(ino);
47 		break;
48 
49 	case FSID_ENCODE_DEV:
50 		fsidv[0] = new_encode_dev(dev);
51 		fsidv[1] = ino_t_to_u32(ino);
52 		break;
53 
54 	case FSID_UUID4_INUM:
55 		/* 4 byte fsid and inode number */
56 		up = (u32*)uuid;
57 		fsidv[0] = ino_t_to_u32(ino);
58 		fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
59 		break;
60 
61 	case FSID_UUID8:
62 		/* 8 byte fsid  */
63 		up = (u32*)uuid;
64 		fsidv[0] = up[0] ^ up[2];
65 		fsidv[1] = up[1] ^ up[3];
66 		break;
67 
68 	case FSID_UUID16:
69 		/* 16 byte fsid - NFSv3+ only */
70 		memcpy(fsidv, uuid, 16);
71 		break;
72 
73 	case FSID_UUID16_INUM:
74 		/* 8 byte inode and 16 byte fsid */
75 		*(u64*)fsidv = (u64)ino;
76 		memcpy(fsidv+2, uuid, 16);
77 		break;
78 	default: BUG();
79 	}
80 }
81 
82 static inline int key_len(int type)
83 {
84 	switch(type) {
85 	case FSID_DEV:		return 8;
86 	case FSID_NUM: 		return 4;
87 	case FSID_MAJOR_MINOR:	return 12;
88 	case FSID_ENCODE_DEV:	return 8;
89 	case FSID_UUID4_INUM:	return 8;
90 	case FSID_UUID8:	return 8;
91 	case FSID_UUID16:	return 16;
92 	case FSID_UUID16_INUM:	return 24;
93 	default: return 0;
94 	}
95 }
96 
97 /*
98  * Shorthand for dprintk()'s
99  */
100 extern char * SVCFH_fmt(struct svc_fh *fhp);
101 
102 /*
103  * Function prototypes
104  */
105 __be32	fh_verify(struct svc_rqst *, struct svc_fh *, umode_t, int);
106 __be32	fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *);
107 __be32	fh_update(struct svc_fh *);
108 void	fh_put(struct svc_fh *);
109 
110 static __inline__ struct svc_fh *
111 fh_copy(struct svc_fh *dst, struct svc_fh *src)
112 {
113 	WARN_ON(src->fh_dentry || src->fh_locked);
114 
115 	*dst = *src;
116 	return dst;
117 }
118 
119 static inline void
120 fh_copy_shallow(struct knfsd_fh *dst, struct knfsd_fh *src)
121 {
122 	dst->fh_size = src->fh_size;
123 	memcpy(&dst->fh_base, &src->fh_base, src->fh_size);
124 }
125 
126 static __inline__ struct svc_fh *
127 fh_init(struct svc_fh *fhp, int maxsize)
128 {
129 	memset(fhp, 0, sizeof(*fhp));
130 	fhp->fh_maxsize = maxsize;
131 	return fhp;
132 }
133 
134 #ifdef CONFIG_NFSD_V3
135 /*
136  * Fill in the pre_op attr for the wcc data
137  */
138 static inline void
139 fill_pre_wcc(struct svc_fh *fhp)
140 {
141 	struct inode    *inode;
142 
143 	inode = fhp->fh_dentry->d_inode;
144 	if (!fhp->fh_pre_saved) {
145 		fhp->fh_pre_mtime = inode->i_mtime;
146 		fhp->fh_pre_ctime = inode->i_ctime;
147 		fhp->fh_pre_size  = inode->i_size;
148 		fhp->fh_pre_change = inode->i_version;
149 		fhp->fh_pre_saved = 1;
150 	}
151 }
152 
153 extern void fill_post_wcc(struct svc_fh *);
154 #else
155 #define	fill_pre_wcc(ignored)
156 #define fill_post_wcc(notused)
157 #endif /* CONFIG_NFSD_V3 */
158 
159 
160 /*
161  * Lock a file handle/inode
162  * NOTE: both fh_lock and fh_unlock are done "by hand" in
163  * vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
164  * so, any changes here should be reflected there.
165  */
166 
167 static inline void
168 fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
169 {
170 	struct dentry	*dentry = fhp->fh_dentry;
171 	struct inode	*inode;
172 
173 	BUG_ON(!dentry);
174 
175 	if (fhp->fh_locked) {
176 		printk(KERN_WARNING "fh_lock: %s/%s already locked!\n",
177 			dentry->d_parent->d_name.name, dentry->d_name.name);
178 		return;
179 	}
180 
181 	inode = dentry->d_inode;
182 	mutex_lock_nested(&inode->i_mutex, subclass);
183 	fill_pre_wcc(fhp);
184 	fhp->fh_locked = 1;
185 }
186 
187 static inline void
188 fh_lock(struct svc_fh *fhp)
189 {
190 	fh_lock_nested(fhp, I_MUTEX_NORMAL);
191 }
192 
193 /*
194  * Unlock a file handle/inode
195  */
196 static inline void
197 fh_unlock(struct svc_fh *fhp)
198 {
199 	if (fhp->fh_locked) {
200 		fill_post_wcc(fhp);
201 		mutex_unlock(&fhp->fh_dentry->d_inode->i_mutex);
202 		fhp->fh_locked = 0;
203 	}
204 }
205 
206 #endif /* _LINUX_NFSD_FH_INT_H */
207