1 /*
2  * Super block/filesystem wide operations
3  *
4  * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and
5  * Michael Callahan <callahan@maths.ox.ac.uk>
6  *
7  * Rewritten for Linux 2.1.  Peter Braam <braam@cs.cmu.edu>
8  * Copyright (C) Carnegie Mellon University
9  */
10 
11 #define __NO_VERSION__
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/mm.h>
15 #include <linux/string.h>
16 #include <linux/stat.h>
17 #include <linux/errno.h>
18 #include <linux/locks.h>
19 #include <linux/unistd.h>
20 #include <linux/smp_lock.h>
21 #include <linux/file.h>
22 
23 #include <asm/system.h>
24 #include <asm/uaccess.h>
25 
26 #include <linux/fs.h>
27 #include <linux/vmalloc.h>
28 
29 #include <linux/coda.h>
30 #include <linux/coda_linux.h>
31 #include <linux/coda_psdev.h>
32 #include <linux/coda_fs_i.h>
33 #include <linux/coda_cache.h>
34 
35 /* VFS super_block ops */
36 static struct super_block *coda_read_super(struct super_block *, void *, int);
37 static void coda_read_inode(struct inode *);
38 static void coda_clear_inode(struct inode *);
39 static void coda_put_super(struct super_block *);
40 static int coda_statfs(struct super_block *sb, struct statfs *buf);
41 
42 /* exported operations */
43 struct super_operations coda_super_operations =
44 {
45 	read_inode:	coda_read_inode,
46 	clear_inode:	coda_clear_inode,
47 	put_super:	coda_put_super,
48 	statfs:		coda_statfs,
49 };
50 
get_device_index(struct coda_mount_data * data)51 static int get_device_index(struct coda_mount_data *data)
52 {
53 	struct file *file;
54 	struct inode *inode;
55 	int idx;
56 
57 	if(data == NULL) {
58 		printk("coda_read_super: Bad mount data\n");
59 		return -1;
60 	}
61 
62 	if(data->version != CODA_MOUNT_VERSION) {
63 		printk("coda_read_super: Bad mount version\n");
64 		return -1;
65 	}
66 
67 	file = fget(data->fd);
68 	inode = NULL;
69 	if(file)
70 		inode = file->f_dentry->d_inode;
71 
72 	if(!inode || !S_ISCHR(inode->i_mode) ||
73 	   MAJOR(inode->i_rdev) != CODA_PSDEV_MAJOR) {
74 		if(file)
75 			fput(file);
76 
77 		printk("coda_read_super: Bad file\n");
78 		return -1;
79 	}
80 
81 	idx = MINOR(inode->i_rdev);
82 	fput(file);
83 
84 	if(idx < 0 || idx >= MAX_CODADEVS) {
85 		printk("coda_read_super: Bad minor number\n");
86 		return -1;
87 	}
88 
89 	return idx;
90 }
91 
coda_read_super(struct super_block * sb,void * data,int silent)92 static struct super_block * coda_read_super(struct super_block *sb,
93 					    void *data, int silent)
94 {
95         struct inode *root = 0;
96 	struct coda_sb_info *sbi = NULL;
97 	struct venus_comm *vc = NULL;
98         ViceFid fid;
99         int error;
100 	int idx;
101 
102 	idx = get_device_index((struct coda_mount_data *) data);
103 
104 	/* Ignore errors in data, for backward compatibility */
105 	if(idx == -1)
106 		idx = 0;
107 
108 	printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
109 
110 	vc = &coda_comms[idx];
111 	if (!vc->vc_inuse) {
112 		printk("coda_read_super: No pseudo device\n");
113 		return NULL;
114 	}
115 
116         if ( vc->vc_sb ) {
117 		printk("coda_read_super: Device already mounted\n");
118 		return NULL;
119 	}
120 
121 	sbi = kmalloc(sizeof(struct coda_sb_info), GFP_KERNEL);
122 	if(!sbi) {
123 		return NULL;
124 	}
125 
126 	vc->vc_sb = sb;
127 
128 	sbi->sbi_sb = sb;
129 	sbi->sbi_vcomm = vc;
130 	INIT_LIST_HEAD(&sbi->sbi_cihead);
131 	init_MUTEX(&sbi->sbi_iget4_mutex);
132 
133         sb->u.generic_sbp = sbi;
134         sb->s_blocksize = 1024;	/* XXXXX  what do we put here?? */
135         sb->s_blocksize_bits = 10;
136         sb->s_magic = CODA_SUPER_MAGIC;
137         sb->s_op = &coda_super_operations;
138 
139 	/* get root fid from Venus: this needs the root inode */
140 	error = venus_rootfid(sb, &fid);
141 	if ( error ) {
142 	        printk("coda_read_super: coda_get_rootfid failed with %d\n",
143 		       error);
144 		goto error;
145 	}
146 	printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
147 
148 	/* make root inode */
149         error = coda_cnode_make(&root, &fid, sb);
150         if ( error || !root ) {
151 	    printk("Failure of coda_cnode_make for root: error %d\n", error);
152 	    goto error;
153 	}
154 
155 	printk("coda_read_super: rootinode is %ld dev %d\n",
156 	       root->i_ino, root->i_dev);
157 	sb->s_root = d_alloc_root(root);
158         return sb;
159 
160  error:
161 	if (sbi) {
162 		kfree(sbi);
163 		if(vc)
164 			vc->vc_sb = NULL;
165 	}
166 	if (root)
167                 iput(root);
168 
169         return NULL;
170 }
171 
coda_put_super(struct super_block * sb)172 static void coda_put_super(struct super_block *sb)
173 {
174         struct coda_sb_info *sbi;
175 
176 	sbi = coda_sbp(sb);
177 	sbi->sbi_vcomm->vc_sb = NULL;
178         list_del_init(&sbi->sbi_cihead);
179 
180 	printk("Coda: Bye bye.\n");
181 	kfree(sbi);
182 }
183 
184 /* all filling in of inodes postponed until lookup */
coda_read_inode(struct inode * inode)185 static void coda_read_inode(struct inode *inode)
186 {
187 	struct coda_sb_info *sbi = coda_sbp(inode->i_sb);
188 	struct coda_inode_info *cii;
189 
190         if (!sbi) BUG();
191 
192 	cii = ITOC(inode);
193 	if (!coda_isnullfid(&cii->c_fid)) {
194             printk("coda_read_inode: initialized inode");
195             return;
196         }
197 
198 	cii->c_mapcount = 0;
199 	list_add(&cii->c_cilist, &sbi->sbi_cihead);
200 }
201 
coda_clear_inode(struct inode * inode)202 static void coda_clear_inode(struct inode *inode)
203 {
204 	struct coda_inode_info *cii = ITOC(inode);
205 
206         CDEBUG(D_SUPER, " inode->ino: %ld, count: %d\n",
207 	       inode->i_ino, atomic_read(&inode->i_count));
208 	CDEBUG(D_DOWNCALL, "clearing inode: %ld, %x\n", inode->i_ino, cii->c_flags);
209 
210         list_del_init(&cii->c_cilist);
211 	coda_cache_clear_inode(inode);
212 }
213 
coda_notify_change(struct dentry * de,struct iattr * iattr)214 int coda_notify_change(struct dentry *de, struct iattr *iattr)
215 {
216 	struct inode *inode = de->d_inode;
217 	struct coda_vattr vattr;
218 	int error;
219 
220 	memset(&vattr, 0, sizeof(vattr));
221 
222 	inode->i_ctime = CURRENT_TIME;
223 	coda_iattr_to_vattr(iattr, &vattr);
224 	vattr.va_type = C_VNON; /* cannot set type */
225 	CDEBUG(D_SUPER, "vattr.va_mode %o\n", vattr.va_mode);
226 
227 	/* Venus is responsible for truncating the container-file!!! */
228 	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
229 
230 	if ( !error ) {
231 	        coda_vattr_to_iattr(inode, &vattr);
232 		coda_cache_clear_inode(inode);
233 	}
234 	CDEBUG(D_SUPER, "inode.i_mode %o, error %d\n", inode->i_mode, error);
235 
236 	return error;
237 }
238 
239 struct inode_operations coda_file_inode_operations = {
240 	permission:	coda_permission,
241 	revalidate:	coda_revalidate_inode,
242 	setattr:	coda_notify_change,
243 };
244 
coda_statfs(struct super_block * sb,struct statfs * buf)245 static int coda_statfs(struct super_block *sb, struct statfs *buf)
246 {
247 	int error;
248 
249 	error = venus_statfs(sb, buf);
250 
251 	if (error) {
252 		/* fake something like AFS does */
253 		buf->f_blocks = 9000000;
254 		buf->f_bfree  = 9000000;
255 		buf->f_bavail = 9000000;
256 		buf->f_files  = 9000000;
257 		buf->f_ffree  = 9000000;
258 	}
259 
260 	/* and fill in the rest */
261 	buf->f_type = CODA_SUPER_MAGIC;
262 	buf->f_bsize = 1024;
263 	buf->f_namelen = CODA_MAXNAMLEN;
264 
265 	return 0;
266 }
267 
268 /* init_coda: used by filesystems.c to register coda */
269 
270 DECLARE_FSTYPE( coda_fs_type, "coda", coda_read_super, 0);
271 
272