xref: /openbmc/linux/fs/coda/inode.c (revision 565d76cb) 
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/mutex.h>
19 #include <linux/spinlock.h>
20 #include <linux/file.h>
21 #include <linux/vfs.h>
22 #include <linux/slab.h>
23 
24 #include <asm/system.h>
25 #include <asm/uaccess.h>
26 
27 #include <linux/fs.h>
28 #include <linux/vmalloc.h>
29 
30 #include <linux/coda.h>
31 #include <linux/coda_psdev.h>
32 #include "coda_linux.h"
33 #include "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 = 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 	spin_lock_init(&ei->c_lock);
55 	return &ei->vfs_inode;
56 }
57 
58 static void coda_i_callback(struct rcu_head *head)
59 {
60 	struct inode *inode = container_of(head, struct inode, i_rcu);
61 	INIT_LIST_HEAD(&inode->i_dentry);
62 	kmem_cache_free(coda_inode_cachep, ITOC(inode));
63 }
64 
65 static void coda_destroy_inode(struct inode *inode)
66 {
67 	call_rcu(&inode->i_rcu, coda_i_callback);
68 }
69 
70 static void init_once(void *foo)
71 {
72 	struct coda_inode_info *ei = (struct coda_inode_info *) foo;
73 
74 	inode_init_once(&ei->vfs_inode);
75 }
76 
77 int coda_init_inodecache(void)
78 {
79 	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
80 				sizeof(struct coda_inode_info),
81 				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
82 				init_once);
83 	if (coda_inode_cachep == NULL)
84 		return -ENOMEM;
85 	return 0;
86 }
87 
88 void coda_destroy_inodecache(void)
89 {
90 	kmem_cache_destroy(coda_inode_cachep);
91 }
92 
93 static int coda_remount(struct super_block *sb, int *flags, char *data)
94 {
95 	*flags |= MS_NOATIME;
96 	return 0;
97 }
98 
99 /* exported operations */
100 static const struct super_operations coda_super_operations =
101 {
102 	.alloc_inode	= coda_alloc_inode,
103 	.destroy_inode	= coda_destroy_inode,
104 	.evict_inode	= coda_evict_inode,
105 	.put_super	= coda_put_super,
106 	.statfs		= coda_statfs,
107 	.remount_fs	= coda_remount,
108 };
109 
110 static int get_device_index(struct coda_mount_data *data)
111 {
112 	struct file *file;
113 	struct inode *inode;
114 	int idx;
115 
116 	if(data == NULL) {
117 		printk("coda_read_super: Bad mount data\n");
118 		return -1;
119 	}
120 
121 	if(data->version != CODA_MOUNT_VERSION) {
122 		printk("coda_read_super: Bad mount version\n");
123 		return -1;
124 	}
125 
126 	file = fget(data->fd);
127 	inode = NULL;
128 	if(file)
129 		inode = file->f_path.dentry->d_inode;
130 
131 	if(!inode || !S_ISCHR(inode->i_mode) ||
132 	   imajor(inode) != CODA_PSDEV_MAJOR) {
133 		if(file)
134 			fput(file);
135 
136 		printk("coda_read_super: Bad file\n");
137 		return -1;
138 	}
139 
140 	idx = iminor(inode);
141 	fput(file);
142 
143 	if(idx < 0 || idx >= MAX_CODADEVS) {
144 		printk("coda_read_super: Bad minor number\n");
145 		return -1;
146 	}
147 
148 	return idx;
149 }
150 
151 static int coda_fill_super(struct super_block *sb, void *data, int silent)
152 {
153 	struct inode *root = NULL;
154 	struct venus_comm *vc;
155 	struct CodaFid fid;
156 	int error;
157 	int idx;
158 
159 	idx = get_device_index((struct coda_mount_data *) data);
160 
161 	/* Ignore errors in data, for backward compatibility */
162 	if(idx == -1)
163 		idx = 0;
164 
165 	printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
166 
167 	vc = &coda_comms[idx];
168 	mutex_lock(&vc->vc_mutex);
169 
170 	if (!vc->vc_inuse) {
171 		printk("coda_read_super: No pseudo device\n");
172 		error = -EINVAL;
173 		goto unlock_out;
174 	}
175 
176 	if (vc->vc_sb) {
177 		printk("coda_read_super: Device already mounted\n");
178 		error = -EBUSY;
179 		goto unlock_out;
180 	}
181 
182 	error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY);
183 	if (error)
184 		goto unlock_out;
185 
186 	vc->vc_sb = sb;
187 	mutex_unlock(&vc->vc_mutex);
188 
189 	sb->s_fs_info = vc;
190 	sb->s_flags |= MS_NOATIME;
191 	sb->s_blocksize = 4096;	/* XXXXX  what do we put here?? */
192 	sb->s_blocksize_bits = 12;
193 	sb->s_magic = CODA_SUPER_MAGIC;
194 	sb->s_op = &coda_super_operations;
195 	sb->s_d_op = &coda_dentry_operations;
196 	sb->s_bdi = &vc->bdi;
197 
198 	/* get root fid from Venus: this needs the root inode */
199 	error = venus_rootfid(sb, &fid);
200 	if ( error ) {
201 	        printk("coda_read_super: coda_get_rootfid failed with %d\n",
202 		       error);
203 		goto error;
204 	}
205 	printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
206 
207 	/* make root inode */
208         error = coda_cnode_make(&root, &fid, sb);
209         if ( error || !root ) {
210 	    printk("Failure of coda_cnode_make for root: error %d\n", error);
211 	    goto error;
212 	}
213 
214 	printk("coda_read_super: rootinode is %ld dev %s\n",
215 	       root->i_ino, root->i_sb->s_id);
216 	sb->s_root = d_alloc_root(root);
217 	if (!sb->s_root) {
218 		error = -EINVAL;
219 		goto error;
220 	}
221 	return 0;
222 
223 error:
224 	if (root)
225 		iput(root);
226 
227 	mutex_lock(&vc->vc_mutex);
228 	bdi_destroy(&vc->bdi);
229 	vc->vc_sb = NULL;
230 	sb->s_fs_info = NULL;
231 unlock_out:
232 	mutex_unlock(&vc->vc_mutex);
233 	return error;
234 }
235 
236 static void coda_put_super(struct super_block *sb)
237 {
238 	struct venus_comm *vcp = coda_vcp(sb);
239 	mutex_lock(&vcp->vc_mutex);
240 	bdi_destroy(&vcp->bdi);
241 	vcp->vc_sb = NULL;
242 	sb->s_fs_info = NULL;
243 	mutex_unlock(&vcp->vc_mutex);
244 
245 	printk("Coda: Bye bye.\n");
246 }
247 
248 static void coda_evict_inode(struct inode *inode)
249 {
250 	truncate_inode_pages(&inode->i_data, 0);
251 	end_writeback(inode);
252 	coda_cache_clear_inode(inode);
253 }
254 
255 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
256 {
257 	int err = coda_revalidate_inode(dentry);
258 	if (!err)
259 		generic_fillattr(dentry->d_inode, stat);
260 	return err;
261 }
262 
263 int coda_setattr(struct dentry *de, struct iattr *iattr)
264 {
265 	struct inode *inode = de->d_inode;
266 	struct coda_vattr vattr;
267 	int error;
268 
269 	memset(&vattr, 0, sizeof(vattr));
270 
271 	inode->i_ctime = CURRENT_TIME_SEC;
272 	coda_iattr_to_vattr(iattr, &vattr);
273 	vattr.va_type = C_VNON; /* cannot set type */
274 
275 	/* Venus is responsible for truncating the container-file!!! */
276 	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
277 
278 	if (!error) {
279 	        coda_vattr_to_iattr(inode, &vattr);
280 		coda_cache_clear_inode(inode);
281 	}
282 	return error;
283 }
284 
285 const struct inode_operations coda_file_inode_operations = {
286 	.permission	= coda_permission,
287 	.getattr	= coda_getattr,
288 	.setattr	= coda_setattr,
289 };
290 
291 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
292 {
293 	int error;
294 
295 	error = venus_statfs(dentry, buf);
296 
297 	if (error) {
298 		/* fake something like AFS does */
299 		buf->f_blocks = 9000000;
300 		buf->f_bfree  = 9000000;
301 		buf->f_bavail = 9000000;
302 		buf->f_files  = 9000000;
303 		buf->f_ffree  = 9000000;
304 	}
305 
306 	/* and fill in the rest */
307 	buf->f_type = CODA_SUPER_MAGIC;
308 	buf->f_bsize = 4096;
309 	buf->f_namelen = CODA_MAXNAMLEN;
310 
311 	return 0;
312 }
313 
314 /* init_coda: used by filesystems.c to register coda */
315 
316 static struct dentry *coda_mount(struct file_system_type *fs_type,
317 	int flags, const char *dev_name, void *data)
318 {
319 	return mount_nodev(fs_type, flags, data, coda_fill_super);
320 }
321 
322 struct file_system_type coda_fs_type = {
323 	.owner		= THIS_MODULE,
324 	.name		= "coda",
325 	.mount		= coda_mount,
326 	.kill_sb	= kill_anon_super,
327 	.fs_flags	= FS_BINARY_MOUNTDATA,
328 };
329 
330