xref: /linux/fs/coda/inode.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb) 
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 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/mm.h>
14 #include <linux/string.h>
15 #include <linux/stat.h>
16 #include <linux/errno.h>
17 #include <linux/unistd.h>
18 #include <linux/smp_lock.h>
19 #include <linux/file.h>
20 #include <linux/vfs.h>
21 #include <linux/slab.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 #include "coda_int.h"
36 
37 /* VFS super_block ops */
38 static void coda_evict_inode(struct inode *);
39 static void coda_put_super(struct super_block *);
40 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
41 
42 static struct kmem_cache * coda_inode_cachep;
43 
44 static struct inode *coda_alloc_inode(struct super_block *sb)
45 {
46 	struct coda_inode_info *ei;
47 	ei = (struct coda_inode_info *)kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
48 	if (!ei)
49 		return NULL;
50 	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
51 	ei->c_flags = 0;
52 	ei->c_uid = 0;
53 	ei->c_cached_perm = 0;
54 	return &ei->vfs_inode;
55 }
56 
57 static void coda_destroy_inode(struct inode *inode)
58 {
59 	kmem_cache_free(coda_inode_cachep, ITOC(inode));
60 }
61 
62 static void init_once(void *foo)
63 {
64 	struct coda_inode_info *ei = (struct coda_inode_info *) foo;
65 
66 	inode_init_once(&ei->vfs_inode);
67 }
68 
69 int coda_init_inodecache(void)
70 {
71 	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
72 				sizeof(struct coda_inode_info),
73 				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
74 				init_once);
75 	if (coda_inode_cachep == NULL)
76 		return -ENOMEM;
77 	return 0;
78 }
79 
80 void coda_destroy_inodecache(void)
81 {
82 	kmem_cache_destroy(coda_inode_cachep);
83 }
84 
85 static int coda_remount(struct super_block *sb, int *flags, char *data)
86 {
87 	*flags |= MS_NOATIME;
88 	return 0;
89 }
90 
91 /* exported operations */
92 static const struct super_operations coda_super_operations =
93 {
94 	.alloc_inode	= coda_alloc_inode,
95 	.destroy_inode	= coda_destroy_inode,
96 	.evict_inode	= coda_evict_inode,
97 	.put_super	= coda_put_super,
98 	.statfs		= coda_statfs,
99 	.remount_fs	= coda_remount,
100 };
101 
102 static int get_device_index(struct coda_mount_data *data)
103 {
104 	struct file *file;
105 	struct inode *inode;
106 	int idx;
107 
108 	if(data == NULL) {
109 		printk("coda_read_super: Bad mount data\n");
110 		return -1;
111 	}
112 
113 	if(data->version != CODA_MOUNT_VERSION) {
114 		printk("coda_read_super: Bad mount version\n");
115 		return -1;
116 	}
117 
118 	file = fget(data->fd);
119 	inode = NULL;
120 	if(file)
121 		inode = file->f_path.dentry->d_inode;
122 
123 	if(!inode || !S_ISCHR(inode->i_mode) ||
124 	   imajor(inode) != CODA_PSDEV_MAJOR) {
125 		if(file)
126 			fput(file);
127 
128 		printk("coda_read_super: Bad file\n");
129 		return -1;
130 	}
131 
132 	idx = iminor(inode);
133 	fput(file);
134 
135 	if(idx < 0 || idx >= MAX_CODADEVS) {
136 		printk("coda_read_super: Bad minor number\n");
137 		return -1;
138 	}
139 
140 	return idx;
141 }
142 
143 static int coda_fill_super(struct super_block *sb, void *data, int silent)
144 {
145 	struct inode *root = NULL;
146 	struct venus_comm *vc = NULL;
147 	struct CodaFid fid;
148 	int error;
149 	int idx;
150 
151 	idx = get_device_index((struct coda_mount_data *) data);
152 
153 	/* Ignore errors in data, for backward compatibility */
154 	if(idx == -1)
155 		idx = 0;
156 
157 	printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
158 
159 	vc = &coda_comms[idx];
160 	if (!vc->vc_inuse) {
161 		printk("coda_read_super: No pseudo device\n");
162 		return -EINVAL;
163 	}
164 
165         if ( vc->vc_sb ) {
166 		printk("coda_read_super: Device already mounted\n");
167 		return -EBUSY;
168 	}
169 
170 	error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY);
171 	if (error)
172 		goto bdi_err;
173 
174 	vc->vc_sb = sb;
175 
176 	sb->s_fs_info = vc;
177 	sb->s_flags |= MS_NOATIME;
178 	sb->s_blocksize = 4096;	/* XXXXX  what do we put here?? */
179 	sb->s_blocksize_bits = 12;
180 	sb->s_magic = CODA_SUPER_MAGIC;
181 	sb->s_op = &coda_super_operations;
182 	sb->s_bdi = &vc->bdi;
183 
184 	/* get root fid from Venus: this needs the root inode */
185 	error = venus_rootfid(sb, &fid);
186 	if ( error ) {
187 	        printk("coda_read_super: coda_get_rootfid failed with %d\n",
188 		       error);
189 		goto error;
190 	}
191 	printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
192 
193 	/* make root inode */
194         error = coda_cnode_make(&root, &fid, sb);
195         if ( error || !root ) {
196 	    printk("Failure of coda_cnode_make for root: error %d\n", error);
197 	    goto error;
198 	}
199 
200 	printk("coda_read_super: rootinode is %ld dev %s\n",
201 	       root->i_ino, root->i_sb->s_id);
202 	sb->s_root = d_alloc_root(root);
203 	if (!sb->s_root)
204 		goto error;
205         return 0;
206 
207  error:
208 	bdi_destroy(&vc->bdi);
209  bdi_err:
210 	if (root)
211 		iput(root);
212 	if (vc)
213 		vc->vc_sb = NULL;
214 
215 	return -EINVAL;
216 }
217 
218 static void coda_put_super(struct super_block *sb)
219 {
220 	bdi_destroy(&coda_vcp(sb)->bdi);
221 	coda_vcp(sb)->vc_sb = NULL;
222 	sb->s_fs_info = NULL;
223 
224 	printk("Coda: Bye bye.\n");
225 }
226 
227 static void coda_evict_inode(struct inode *inode)
228 {
229 	truncate_inode_pages(&inode->i_data, 0);
230 	end_writeback(inode);
231 	coda_cache_clear_inode(inode);
232 }
233 
234 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
235 {
236 	int err = coda_revalidate_inode(dentry);
237 	if (!err)
238 		generic_fillattr(dentry->d_inode, stat);
239 	return err;
240 }
241 
242 int coda_setattr(struct dentry *de, struct iattr *iattr)
243 {
244 	struct inode *inode = de->d_inode;
245 	struct coda_vattr vattr;
246 	int error;
247 
248 	lock_kernel();
249 
250 	memset(&vattr, 0, sizeof(vattr));
251 
252 	inode->i_ctime = CURRENT_TIME_SEC;
253 	coda_iattr_to_vattr(iattr, &vattr);
254 	vattr.va_type = C_VNON; /* cannot set type */
255 
256 	/* Venus is responsible for truncating the container-file!!! */
257 	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
258 
259 	if ( !error ) {
260 	        coda_vattr_to_iattr(inode, &vattr);
261 		coda_cache_clear_inode(inode);
262 	}
263 
264 	unlock_kernel();
265 
266 	return error;
267 }
268 
269 const struct inode_operations coda_file_inode_operations = {
270 	.permission	= coda_permission,
271 	.getattr	= coda_getattr,
272 	.setattr	= coda_setattr,
273 };
274 
275 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
276 {
277 	int error;
278 
279 	lock_kernel();
280 
281 	error = venus_statfs(dentry, buf);
282 
283 	unlock_kernel();
284 
285 	if (error) {
286 		/* fake something like AFS does */
287 		buf->f_blocks = 9000000;
288 		buf->f_bfree  = 9000000;
289 		buf->f_bavail = 9000000;
290 		buf->f_files  = 9000000;
291 		buf->f_ffree  = 9000000;
292 	}
293 
294 	/* and fill in the rest */
295 	buf->f_type = CODA_SUPER_MAGIC;
296 	buf->f_bsize = 4096;
297 	buf->f_namelen = CODA_MAXNAMLEN;
298 
299 	return 0;
300 }
301 
302 /* init_coda: used by filesystems.c to register coda */
303 
304 static int coda_get_sb(struct file_system_type *fs_type,
305 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
306 {
307 	return get_sb_nodev(fs_type, flags, data, coda_fill_super, mnt);
308 }
309 
310 struct file_system_type coda_fs_type = {
311 	.owner		= THIS_MODULE,
312 	.name		= "coda",
313 	.get_sb		= coda_get_sb,
314 	.kill_sb	= kill_anon_super,
315 	.fs_flags	= FS_BINARY_MOUNTDATA,
316 };
317 
318