xref: /openbmc/linux/fs/coda/cnode.c (revision 1da177e4)
1 /* cnode related routines for the coda kernel code
2    (C) 1996 Peter Braam
3    */
4 
5 #include <linux/types.h>
6 #include <linux/string.h>
7 #include <linux/time.h>
8 
9 #include <linux/coda.h>
10 #include <linux/coda_linux.h>
11 #include <linux/coda_fs_i.h>
12 #include <linux/coda_psdev.h>
13 
14 static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2)
15 {
16 	return memcmp(fid1, fid2, sizeof(*fid1)) == 0;
17 }
18 
19 static struct inode_operations coda_symlink_inode_operations = {
20 	.readlink	= generic_readlink,
21 	.follow_link	= page_follow_link_light,
22 	.put_link	= page_put_link,
23 	.setattr	= coda_setattr,
24 };
25 
26 /* cnode.c */
27 static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr)
28 {
29         coda_vattr_to_iattr(inode, attr);
30 
31         if (S_ISREG(inode->i_mode)) {
32                 inode->i_op = &coda_file_inode_operations;
33                 inode->i_fop = &coda_file_operations;
34         } else if (S_ISDIR(inode->i_mode)) {
35                 inode->i_op = &coda_dir_inode_operations;
36                 inode->i_fop = &coda_dir_operations;
37         } else if (S_ISLNK(inode->i_mode)) {
38 		inode->i_op = &coda_symlink_inode_operations;
39 		inode->i_data.a_ops = &coda_symlink_aops;
40 		inode->i_mapping = &inode->i_data;
41 	} else
42                 init_special_inode(inode, inode->i_mode, huge_decode_dev(attr->va_rdev));
43 }
44 
45 static int coda_test_inode(struct inode *inode, void *data)
46 {
47 	struct CodaFid *fid = (struct CodaFid *)data;
48 	return coda_fideq(&(ITOC(inode)->c_fid), fid);
49 }
50 
51 static int coda_set_inode(struct inode *inode, void *data)
52 {
53 	struct CodaFid *fid = (struct CodaFid *)data;
54 	ITOC(inode)->c_fid = *fid;
55 	return 0;
56 }
57 
58 static int coda_fail_inode(struct inode *inode, void *data)
59 {
60 	return -1;
61 }
62 
63 struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
64 			 struct coda_vattr * attr)
65 {
66 	struct inode *inode;
67 	struct coda_inode_info *cii;
68 	unsigned long hash = coda_f2i(fid);
69 
70 	inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
71 
72 	if (!inode)
73 		return ERR_PTR(-ENOMEM);
74 
75 	if (inode->i_state & I_NEW) {
76 		cii = ITOC(inode);
77 		/* we still need to set i_ino for things like stat(2) */
78 		inode->i_ino = hash;
79 		cii->c_mapcount = 0;
80 		unlock_new_inode(inode);
81 	}
82 
83 	/* always replace the attributes, type might have changed */
84 	coda_fill_inode(inode, attr);
85 	return inode;
86 }
87 
88 /* this is effectively coda_iget:
89    - get attributes (might be cached)
90    - get the inode for the fid using vfs iget
91    - link the two up if this is needed
92    - fill in the attributes
93 */
94 int coda_cnode_make(struct inode **inode, struct CodaFid *fid, struct super_block *sb)
95 {
96         struct coda_vattr attr;
97         int error;
98 
99 	/* We get inode numbers from Venus -- see venus source */
100 	error = venus_getattr(sb, fid, &attr);
101 	if ( error ) {
102 	    *inode = NULL;
103 	    return error;
104 	}
105 
106 	*inode = coda_iget(sb, fid, &attr);
107 	if ( IS_ERR(*inode) ) {
108 		printk("coda_cnode_make: coda_iget failed\n");
109                 return PTR_ERR(*inode);
110         }
111 	return 0;
112 }
113 
114 
115 void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid,
116 		      struct CodaFid *newfid)
117 {
118 	struct coda_inode_info *cii;
119 	unsigned long hash = coda_f2i(newfid);
120 
121 	cii = ITOC(inode);
122 
123 	if (!coda_fideq(&cii->c_fid, oldfid))
124 		BUG();
125 
126 	/* replace fid and rehash inode */
127 	/* XXX we probably need to hold some lock here! */
128 	remove_inode_hash(inode);
129 	cii->c_fid = *newfid;
130 	inode->i_ino = hash;
131 	__insert_inode_hash(inode, hash);
132 }
133 
134 /* convert a fid to an inode. */
135 struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb)
136 {
137 	struct inode *inode;
138 	unsigned long hash = coda_f2i(fid);
139 
140 	if ( !sb ) {
141 		printk("coda_fid_to_inode: no sb!\n");
142 		return NULL;
143 	}
144 
145 	inode = iget5_locked(sb, hash, coda_test_inode, coda_fail_inode, fid);
146 	if ( !inode )
147 		return NULL;
148 
149 	/* we should never see newly created inodes because we intentionally
150 	 * fail in the initialization callback */
151 	BUG_ON(inode->i_state & I_NEW);
152 
153 	return inode;
154 }
155 
156 /* the CONTROL inode is made without asking attributes from Venus */
157 int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
158 {
159 	int error = -ENOMEM;
160 
161 	*inode = new_inode(sb);
162 	if (*inode) {
163 		(*inode)->i_ino = CTL_INO;
164 		(*inode)->i_op = &coda_ioctl_inode_operations;
165 		(*inode)->i_fop = &coda_ioctl_operations;
166 		(*inode)->i_mode = 0444;
167 		error = 0;
168 	}
169 
170 	return error;
171 }
172 
173