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
22#include <asm/system.h>
23#include <asm/uaccess.h>
24
25#include <linux/fs.h>
26#include <linux/vmalloc.h>
27
28#include <linux/coda.h>
29#include <linux/coda_linux.h>
30#include <linux/coda_psdev.h>
31#include <linux/coda_fs_i.h>
32#include <linux/coda_cache.h>
33
34#include "coda_int.h"
35
36/* VFS super_block ops */
37static void coda_clear_inode(struct inode *);
38static void coda_put_super(struct super_block *);
39static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
40
41static struct kmem_cache * coda_inode_cachep;
42
43static struct inode *coda_alloc_inode(struct super_block *sb)
44{
45	struct coda_inode_info *ei;
46	ei = (struct coda_inode_info *)kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
47	if (!ei)
48		return NULL;
49	memset(&ei->c_fid, 0, sizeof(struct CodaFid));
50	ei->c_flags = 0;
51	ei->c_uid = 0;
52	ei->c_cached_perm = 0;
53	return &ei->vfs_inode;
54}
55
56static void coda_destroy_inode(struct inode *inode)
57{
58	kmem_cache_free(coda_inode_cachep, ITOC(inode));
59}
60
61static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
62{
63	struct coda_inode_info *ei = (struct coda_inode_info *) foo;
64
65	inode_init_once(&ei->vfs_inode);
66}
67
68int coda_init_inodecache(void)
69{
70	coda_inode_cachep = kmem_cache_create("coda_inode_cache",
71				sizeof(struct coda_inode_info),
72				0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
73				init_once, NULL);
74	if (coda_inode_cachep == NULL)
75		return -ENOMEM;
76	return 0;
77}
78
79void coda_destroy_inodecache(void)
80{
81	kmem_cache_destroy(coda_inode_cachep);
82}
83
84static int coda_remount(struct super_block *sb, int *flags, char *data)
85{
86	*flags |= MS_NODIRATIME;
87	return 0;
88}
89
90/* exported operations */
91static const struct super_operations coda_super_operations =
92{
93	.alloc_inode	= coda_alloc_inode,
94	.destroy_inode	= coda_destroy_inode,
95	.clear_inode	= coda_clear_inode,
96	.put_super	= coda_put_super,
97	.statfs		= coda_statfs,
98	.remount_fs	= coda_remount,
99};
100
101static int get_device_index(struct coda_mount_data *data)
102{
103	struct file *file;
104	struct inode *inode;
105	int idx;
106
107	if(data == NULL) {
108		printk("coda_read_super: Bad mount data\n");
109		return -1;
110	}
111
112	if(data->version != CODA_MOUNT_VERSION) {
113		printk("coda_read_super: Bad mount version\n");
114		return -1;
115	}
116
117	file = fget(data->fd);
118	inode = NULL;
119	if(file)
120		inode = file->f_path.dentry->d_inode;
121
122	if(!inode || !S_ISCHR(inode->i_mode) ||
123	   imajor(inode) != CODA_PSDEV_MAJOR) {
124		if(file)
125			fput(file);
126
127		printk("coda_read_super: Bad file\n");
128		return -1;
129	}
130
131	idx = iminor(inode);
132	fput(file);
133
134	if(idx < 0 || idx >= MAX_CODADEVS) {
135		printk("coda_read_super: Bad minor number\n");
136		return -1;
137	}
138
139	return idx;
140}
141
142static int coda_fill_super(struct super_block *sb, void *data, int silent)
143{
144        struct inode *root = NULL;
145	struct coda_sb_info *sbi = 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	sbi = kmalloc(sizeof(struct coda_sb_info), GFP_KERNEL);
171	if(!sbi) {
172		return -ENOMEM;
173	}
174
175	vc->vc_sb = sb;
176
177	sbi->sbi_vcomm = vc;
178
179        sb->s_fs_info = sbi;
180	sb->s_flags |= MS_NODIRATIME; /* probably even noatime */
181        sb->s_blocksize = 1024;	/* XXXXX  what do we put here?? */
182        sb->s_blocksize_bits = 10;
183        sb->s_magic = CODA_SUPER_MAGIC;
184        sb->s_op = &coda_super_operations;
185
186	/* get root fid from Venus: this needs the root inode */
187	error = venus_rootfid(sb, &fid);
188	if ( error ) {
189	        printk("coda_read_super: coda_get_rootfid failed with %d\n",
190		       error);
191		goto error;
192	}
193	printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
194
195	/* make root inode */
196        error = coda_cnode_make(&root, &fid, sb);
197        if ( error || !root ) {
198	    printk("Failure of coda_cnode_make for root: error %d\n", error);
199	    goto error;
200	}
201
202	printk("coda_read_super: rootinode is %ld dev %s\n",
203	       root->i_ino, root->i_sb->s_id);
204	sb->s_root = d_alloc_root(root);
205	if (!sb->s_root)
206		goto error;
207        return 0;
208
209 error:
210	if (sbi) {
211		kfree(sbi);
212		if(vc)
213			vc->vc_sb = NULL;
214	}
215	if (root)
216                iput(root);
217
218        return -EINVAL;
219}
220
221static void coda_put_super(struct super_block *sb)
222{
223        struct coda_sb_info *sbi;
224
225	sbi = coda_sbp(sb);
226	sbi->sbi_vcomm->vc_sb = NULL;
227
228	printk("Coda: Bye bye.\n");
229	kfree(sbi);
230}
231
232static void coda_clear_inode(struct inode *inode)
233{
234	coda_cache_clear_inode(inode);
235}
236
237int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
238{
239	int err = coda_revalidate_inode(dentry);
240	if (!err)
241		generic_fillattr(dentry->d_inode, stat);
242	return err;
243}
244
245int coda_setattr(struct dentry *de, struct iattr *iattr)
246{
247	struct inode *inode = de->d_inode;
248	struct coda_vattr vattr;
249	int error;
250
251	lock_kernel();
252
253	memset(&vattr, 0, sizeof(vattr));
254
255	inode->i_ctime = CURRENT_TIME_SEC;
256	coda_iattr_to_vattr(iattr, &vattr);
257	vattr.va_type = C_VNON; /* cannot set type */
258
259	/* Venus is responsible for truncating the container-file!!! */
260	error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
261
262	if ( !error ) {
263	        coda_vattr_to_iattr(inode, &vattr);
264		coda_cache_clear_inode(inode);
265	}
266
267	unlock_kernel();
268
269	return error;
270}
271
272const struct inode_operations coda_file_inode_operations = {
273	.permission	= coda_permission,
274	.getattr	= coda_getattr,
275	.setattr	= coda_setattr,
276};
277
278static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
279{
280	int error;
281
282	lock_kernel();
283
284	error = venus_statfs(dentry, buf);
285
286	unlock_kernel();
287
288	if (error) {
289		/* fake something like AFS does */
290		buf->f_blocks = 9000000;
291		buf->f_bfree  = 9000000;
292		buf->f_bavail = 9000000;
293		buf->f_files  = 9000000;
294		buf->f_ffree  = 9000000;
295	}
296
297	/* and fill in the rest */
298	buf->f_type = CODA_SUPER_MAGIC;
299	buf->f_bsize = 1024;
300	buf->f_namelen = CODA_MAXNAMLEN;
301
302	return 0;
303}
304
305/* init_coda: used by filesystems.c to register coda */
306
307static int coda_get_sb(struct file_system_type *fs_type,
308	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
309{
310	return get_sb_nodev(fs_type, flags, data, coda_fill_super, mnt);
311}
312
313struct file_system_type coda_fs_type = {
314	.owner		= THIS_MODULE,
315	.name		= "coda",
316	.get_sb		= coda_get_sb,
317	.kill_sb	= kill_anon_super,
318	.fs_flags	= FS_BINARY_MOUNTDATA,
319};
320