1/*
2 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
3 *
4 * This file describes the layout of the file handles as passed
5 * over the wire.
6 */
7#ifndef _LINUX_NFSD_NFSFH_H
8#define _LINUX_NFSD_NFSFH_H
9
10#include <linux/sunrpc/svc.h>
11#include <uapi/linux/nfsd/nfsfh.h>
12
13static inline __u32 ino_t_to_u32(ino_t ino)
14{
15	return (__u32) ino;
16}
17
18static inline ino_t u32_to_ino_t(__u32 uino)
19{
20	return (ino_t) uino;
21}
22
23/*
24 * This is the internal representation of an NFS handle used in knfsd.
25 * pre_mtime/post_version will be used to support wcc_attr's in NFSv3.
26 */
27typedef struct svc_fh {
28	struct knfsd_fh		fh_handle;	/* FH data */
29	struct dentry *		fh_dentry;	/* validated dentry */
30	struct svc_export *	fh_export;	/* export pointer */
31	int			fh_maxsize;	/* max size for fh_handle */
32
33	unsigned char		fh_locked;	/* inode locked by us */
34	unsigned char		fh_want_write;	/* remount protection taken */
35
36#ifdef CONFIG_NFSD_V3
37	unsigned char		fh_post_saved;	/* post-op attrs saved */
38	unsigned char		fh_pre_saved;	/* pre-op attrs saved */
39
40	/* Pre-op attributes saved during fh_lock */
41	__u64			fh_pre_size;	/* size before operation */
42	struct timespec		fh_pre_mtime;	/* mtime before oper */
43	struct timespec		fh_pre_ctime;	/* ctime before oper */
44	/*
45	 * pre-op nfsv4 change attr: note must check IS_I_VERSION(inode)
46	 *  to find out if it is valid.
47	 */
48	u64			fh_pre_change;
49
50	/* Post-op attributes saved in fh_unlock */
51	struct kstat		fh_post_attr;	/* full attrs after operation */
52	u64			fh_post_change; /* nfsv4 change; see above */
53#endif /* CONFIG_NFSD_V3 */
54
55} svc_fh;
56
57enum nfsd_fsid {
58	FSID_DEV = 0,
59	FSID_NUM,
60	FSID_MAJOR_MINOR,
61	FSID_ENCODE_DEV,
62	FSID_UUID4_INUM,
63	FSID_UUID8,
64	FSID_UUID16,
65	FSID_UUID16_INUM,
66};
67
68enum fsid_source {
69	FSIDSOURCE_DEV,
70	FSIDSOURCE_FSID,
71	FSIDSOURCE_UUID,
72};
73extern enum fsid_source fsid_source(struct svc_fh *fhp);
74
75
76/*
77 * This might look a little large to "inline" but in all calls except
78 * one, 'vers' is constant so moste of the function disappears.
79 *
80 * In some cases the values are considered to be host endian and in
81 * others, net endian. fsidv is always considered to be u32 as the
82 * callers don't know which it will be. So we must use __force to keep
83 * sparse from complaining. Since these values are opaque to the
84 * client, that shouldn't be a problem.
85 */
86static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
87			   u32 fsid, unsigned char *uuid)
88{
89	u32 *up;
90	switch(vers) {
91	case FSID_DEV:
92		fsidv[0] = (__force __u32)htonl((MAJOR(dev)<<16) |
93				 MINOR(dev));
94		fsidv[1] = ino_t_to_u32(ino);
95		break;
96	case FSID_NUM:
97		fsidv[0] = fsid;
98		break;
99	case FSID_MAJOR_MINOR:
100		fsidv[0] = (__force __u32)htonl(MAJOR(dev));
101		fsidv[1] = (__force __u32)htonl(MINOR(dev));
102		fsidv[2] = ino_t_to_u32(ino);
103		break;
104
105	case FSID_ENCODE_DEV:
106		fsidv[0] = new_encode_dev(dev);
107		fsidv[1] = ino_t_to_u32(ino);
108		break;
109
110	case FSID_UUID4_INUM:
111		/* 4 byte fsid and inode number */
112		up = (u32*)uuid;
113		fsidv[0] = ino_t_to_u32(ino);
114		fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
115		break;
116
117	case FSID_UUID8:
118		/* 8 byte fsid  */
119		up = (u32*)uuid;
120		fsidv[0] = up[0] ^ up[2];
121		fsidv[1] = up[1] ^ up[3];
122		break;
123
124	case FSID_UUID16:
125		/* 16 byte fsid - NFSv3+ only */
126		memcpy(fsidv, uuid, 16);
127		break;
128
129	case FSID_UUID16_INUM:
130		/* 8 byte inode and 16 byte fsid */
131		*(u64*)fsidv = (u64)ino;
132		memcpy(fsidv+2, uuid, 16);
133		break;
134	default: BUG();
135	}
136}
137
138static inline int key_len(int type)
139{
140	switch(type) {
141	case FSID_DEV:		return 8;
142	case FSID_NUM: 		return 4;
143	case FSID_MAJOR_MINOR:	return 12;
144	case FSID_ENCODE_DEV:	return 8;
145	case FSID_UUID4_INUM:	return 8;
146	case FSID_UUID8:	return 8;
147	case FSID_UUID16:	return 16;
148	case FSID_UUID16_INUM:	return 24;
149	default: return 0;
150	}
151}
152
153/*
154 * Shorthand for dprintk()'s
155 */
156extern char * SVCFH_fmt(struct svc_fh *fhp);
157
158/*
159 * Function prototypes
160 */
161__be32	fh_verify(struct svc_rqst *, struct svc_fh *, umode_t, int);
162__be32	fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *);
163__be32	fh_update(struct svc_fh *);
164void	fh_put(struct svc_fh *);
165
166static __inline__ struct svc_fh *
167fh_copy(struct svc_fh *dst, struct svc_fh *src)
168{
169	WARN_ON(src->fh_dentry || src->fh_locked);
170
171	*dst = *src;
172	return dst;
173}
174
175static inline void
176fh_copy_shallow(struct knfsd_fh *dst, struct knfsd_fh *src)
177{
178	dst->fh_size = src->fh_size;
179	memcpy(&dst->fh_base, &src->fh_base, src->fh_size);
180}
181
182static __inline__ struct svc_fh *
183fh_init(struct svc_fh *fhp, int maxsize)
184{
185	memset(fhp, 0, sizeof(*fhp));
186	fhp->fh_maxsize = maxsize;
187	return fhp;
188}
189
190static inline bool fh_match(struct knfsd_fh *fh1, struct knfsd_fh *fh2)
191{
192	if (fh1->fh_size != fh2->fh_size)
193		return false;
194	if (memcmp(fh1->fh_base.fh_pad, fh2->fh_base.fh_pad, fh1->fh_size) != 0)
195		return false;
196	return true;
197}
198
199static inline bool fh_fsid_match(struct knfsd_fh *fh1, struct knfsd_fh *fh2)
200{
201	if (fh1->fh_fsid_type != fh2->fh_fsid_type)
202		return false;
203	if (memcmp(fh1->fh_fsid, fh2->fh_fsid, key_len(fh1->fh_fsid_type)) != 0)
204		return false;
205	return true;
206}
207
208#ifdef CONFIG_NFSD_V3
209/*
210 * The wcc data stored in current_fh should be cleared
211 * between compound ops.
212 */
213static inline void
214fh_clear_wcc(struct svc_fh *fhp)
215{
216	fhp->fh_post_saved = 0;
217	fhp->fh_pre_saved = 0;
218}
219
220/*
221 * Fill in the pre_op attr for the wcc data
222 */
223static inline void
224fill_pre_wcc(struct svc_fh *fhp)
225{
226	struct inode    *inode;
227
228	inode = d_inode(fhp->fh_dentry);
229	if (!fhp->fh_pre_saved) {
230		fhp->fh_pre_mtime = inode->i_mtime;
231		fhp->fh_pre_ctime = inode->i_ctime;
232		fhp->fh_pre_size  = inode->i_size;
233		fhp->fh_pre_change = inode->i_version;
234		fhp->fh_pre_saved = 1;
235	}
236}
237
238extern void fill_post_wcc(struct svc_fh *);
239#else
240#define fh_clear_wcc(ignored)
241#define fill_pre_wcc(ignored)
242#define fill_post_wcc(notused)
243#endif /* CONFIG_NFSD_V3 */
244
245
246/*
247 * Lock a file handle/inode
248 * NOTE: both fh_lock and fh_unlock are done "by hand" in
249 * vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
250 * so, any changes here should be reflected there.
251 */
252
253static inline void
254fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
255{
256	struct dentry	*dentry = fhp->fh_dentry;
257	struct inode	*inode;
258
259	BUG_ON(!dentry);
260
261	if (fhp->fh_locked) {
262		printk(KERN_WARNING "fh_lock: %pd2 already locked!\n",
263			dentry);
264		return;
265	}
266
267	inode = d_inode(dentry);
268	mutex_lock_nested(&inode->i_mutex, subclass);
269	fill_pre_wcc(fhp);
270	fhp->fh_locked = 1;
271}
272
273static inline void
274fh_lock(struct svc_fh *fhp)
275{
276	fh_lock_nested(fhp, I_MUTEX_NORMAL);
277}
278
279/*
280 * Unlock a file handle/inode
281 */
282static inline void
283fh_unlock(struct svc_fh *fhp)
284{
285	if (fhp->fh_locked) {
286		fill_post_wcc(fhp);
287		mutex_unlock(&d_inode(fhp->fh_dentry)->i_mutex);
288		fhp->fh_locked = 0;
289	}
290}
291
292#endif /* _LINUX_NFSD_NFSFH_H */
293