xref: /openbmc/linux/fs/coda/cnode.c (revision 367b8112)
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 const 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 struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
59 			 struct coda_vattr * attr)
60 {
61 	struct inode *inode;
62 	struct coda_inode_info *cii;
63 	unsigned long hash = coda_f2i(fid);
64 
65 	inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
66 
67 	if (!inode)
68 		return ERR_PTR(-ENOMEM);
69 
70 	if (inode->i_state & I_NEW) {
71 		cii = ITOC(inode);
72 		/* we still need to set i_ino for things like stat(2) */
73 		inode->i_ino = hash;
74 		cii->c_mapcount = 0;
75 		unlock_new_inode(inode);
76 	}
77 
78 	/* always replace the attributes, type might have changed */
79 	coda_fill_inode(inode, attr);
80 	return inode;
81 }
82 
83 /* this is effectively coda_iget:
84    - get attributes (might be cached)
85    - get the inode for the fid using vfs iget
86    - link the two up if this is needed
87    - fill in the attributes
88 */
89 int coda_cnode_make(struct inode **inode, struct CodaFid *fid, struct super_block *sb)
90 {
91         struct coda_vattr attr;
92         int error;
93 
94 	/* We get inode numbers from Venus -- see venus source */
95 	error = venus_getattr(sb, fid, &attr);
96 	if ( error ) {
97 	    *inode = NULL;
98 	    return error;
99 	}
100 
101 	*inode = coda_iget(sb, fid, &attr);
102 	if ( IS_ERR(*inode) ) {
103 		printk("coda_cnode_make: coda_iget failed\n");
104                 return PTR_ERR(*inode);
105         }
106 	return 0;
107 }
108 
109 
110 void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid,
111 		      struct CodaFid *newfid)
112 {
113 	struct coda_inode_info *cii;
114 	unsigned long hash = coda_f2i(newfid);
115 
116 	cii = ITOC(inode);
117 
118 	BUG_ON(!coda_fideq(&cii->c_fid, oldfid));
119 
120 	/* replace fid and rehash inode */
121 	/* XXX we probably need to hold some lock here! */
122 	remove_inode_hash(inode);
123 	cii->c_fid = *newfid;
124 	inode->i_ino = hash;
125 	__insert_inode_hash(inode, hash);
126 }
127 
128 /* convert a fid to an inode. */
129 struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb)
130 {
131 	struct inode *inode;
132 	unsigned long hash = coda_f2i(fid);
133 
134 	if ( !sb ) {
135 		printk("coda_fid_to_inode: no sb!\n");
136 		return NULL;
137 	}
138 
139 	inode = ilookup5(sb, hash, coda_test_inode, fid);
140 	if ( !inode )
141 		return NULL;
142 
143 	/* we should never see newly created inodes because we intentionally
144 	 * fail in the initialization callback */
145 	BUG_ON(inode->i_state & I_NEW);
146 
147 	return inode;
148 }
149 
150 /* the CONTROL inode is made without asking attributes from Venus */
151 int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
152 {
153 	int error = -ENOMEM;
154 
155 	*inode = new_inode(sb);
156 	if (*inode) {
157 		(*inode)->i_ino = CTL_INO;
158 		(*inode)->i_op = &coda_ioctl_inode_operations;
159 		(*inode)->i_fop = &coda_ioctl_operations;
160 		(*inode)->i_mode = 0444;
161 		error = 0;
162 	}
163 
164 	return error;
165 }
166 
167