blob: dfebf21289f4904a7ae784e1ab4c57ce97bafd6e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * super.c
3 *
4 * Copyright (c) 1999 Al Smith
5 *
6 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
7 */
8
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/efs_fs.h>
12#include <linux/efs_vh.h>
13#include <linux/efs_fs_sb.h>
14#include <linux/slab.h>
15#include <linux/buffer_head.h>
16#include <linux/vfs.h>
17
David Howells726c3342006-06-23 02:02:58 -070018static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -070019static int efs_fill_super(struct super_block *s, void *d, int silent);
20
David Howells454e2392006-06-23 02:02:57 -070021static int efs_get_sb(struct file_system_type *fs_type,
22 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -070023{
David Howells454e2392006-06-23 02:02:57 -070024 return get_sb_bdev(fs_type, flags, dev_name, data, efs_fill_super, mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -070025}
26
27static struct file_system_type efs_fs_type = {
28 .owner = THIS_MODULE,
29 .name = "efs",
30 .get_sb = efs_get_sb,
31 .kill_sb = kill_block_super,
32 .fs_flags = FS_REQUIRES_DEV,
33};
34
35static struct pt_types sgi_pt_types[] = {
36 {0x00, "SGI vh"},
37 {0x01, "SGI trkrepl"},
38 {0x02, "SGI secrepl"},
39 {0x03, "SGI raw"},
40 {0x04, "SGI bsd"},
41 {SGI_SYSV, "SGI sysv"},
42 {0x06, "SGI vol"},
43 {SGI_EFS, "SGI efs"},
44 {0x08, "SGI lv"},
45 {0x09, "SGI rlv"},
46 {0x0A, "SGI xfs"},
47 {0x0B, "SGI xfslog"},
48 {0x0C, "SGI xlv"},
49 {0x82, "Linux swap"},
50 {0x83, "Linux native"},
51 {0, NULL}
52};
53
54
Christoph Lametere18b8902006-12-06 20:33:20 -080055static struct kmem_cache * efs_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57static struct inode *efs_alloc_inode(struct super_block *sb)
58{
59 struct efs_inode_info *ei;
Christoph Lametere94b1762006-12-06 20:33:17 -080060 ei = (struct efs_inode_info *)kmem_cache_alloc(efs_inode_cachep, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 if (!ei)
62 return NULL;
63 return &ei->vfs_inode;
64}
65
66static void efs_destroy_inode(struct inode *inode)
67{
68 kmem_cache_free(efs_inode_cachep, INODE_INFO(inode));
69}
70
Christoph Lametere18b8902006-12-06 20:33:20 -080071static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -070072{
73 struct efs_inode_info *ei = (struct efs_inode_info *) foo;
74
75 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
76 SLAB_CTOR_CONSTRUCTOR)
77 inode_init_once(&ei->vfs_inode);
78}
79
80static int init_inodecache(void)
81{
82 efs_inode_cachep = kmem_cache_create("efs_inode_cache",
83 sizeof(struct efs_inode_info),
Paul Jackson4b6a9312006-03-24 03:16:05 -080084 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 init_once, NULL);
86 if (efs_inode_cachep == NULL)
87 return -ENOMEM;
88 return 0;
89}
90
91static void destroy_inodecache(void)
92{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -070093 kmem_cache_destroy(efs_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094}
95
96static void efs_put_super(struct super_block *s)
97{
98 kfree(s->s_fs_info);
99 s->s_fs_info = NULL;
100}
101
102static int efs_remount(struct super_block *sb, int *flags, char *data)
103{
104 *flags |= MS_RDONLY;
105 return 0;
106}
107
108static struct super_operations efs_superblock_operations = {
109 .alloc_inode = efs_alloc_inode,
110 .destroy_inode = efs_destroy_inode,
111 .read_inode = efs_read_inode,
112 .put_super = efs_put_super,
113 .statfs = efs_statfs,
114 .remount_fs = efs_remount,
115};
116
117static struct export_operations efs_export_ops = {
118 .get_parent = efs_get_parent,
119};
120
121static int __init init_efs_fs(void) {
122 int err;
123 printk("EFS: "EFS_VERSION" - http://aeschi.ch.eu.org/efs/\n");
124 err = init_inodecache();
125 if (err)
126 goto out1;
127 err = register_filesystem(&efs_fs_type);
128 if (err)
129 goto out;
130 return 0;
131out:
132 destroy_inodecache();
133out1:
134 return err;
135}
136
137static void __exit exit_efs_fs(void) {
138 unregister_filesystem(&efs_fs_type);
139 destroy_inodecache();
140}
141
142module_init(init_efs_fs)
143module_exit(exit_efs_fs)
144
145static efs_block_t efs_validate_vh(struct volume_header *vh) {
146 int i;
147 __be32 cs, *ui;
148 int csum;
149 efs_block_t sblock = 0; /* shuts up gcc */
150 struct pt_types *pt_entry;
151 int pt_type, slice = -1;
152
153 if (be32_to_cpu(vh->vh_magic) != VHMAGIC) {
154 /*
155 * assume that we're dealing with a partition and allow
156 * read_super() to try and detect a valid superblock
157 * on the next block.
158 */
159 return 0;
160 }
161
162 ui = ((__be32 *) (vh + 1)) - 1;
163 for(csum = 0; ui >= ((__be32 *) vh);) {
164 cs = *ui--;
165 csum += be32_to_cpu(cs);
166 }
167 if (csum) {
168 printk(KERN_INFO "EFS: SGI disklabel: checksum bad, label corrupted\n");
169 return 0;
170 }
171
172#ifdef DEBUG
173 printk(KERN_DEBUG "EFS: bf: \"%16s\"\n", vh->vh_bootfile);
174
175 for(i = 0; i < NVDIR; i++) {
176 int j;
177 char name[VDNAMESIZE+1];
178
179 for(j = 0; j < VDNAMESIZE; j++) {
180 name[j] = vh->vh_vd[i].vd_name[j];
181 }
182 name[j] = (char) 0;
183
184 if (name[0]) {
185 printk(KERN_DEBUG "EFS: vh: %8s block: 0x%08x size: 0x%08x\n",
186 name,
187 (int) be32_to_cpu(vh->vh_vd[i].vd_lbn),
188 (int) be32_to_cpu(vh->vh_vd[i].vd_nbytes));
189 }
190 }
191#endif
192
193 for(i = 0; i < NPARTAB; i++) {
194 pt_type = (int) be32_to_cpu(vh->vh_pt[i].pt_type);
195 for(pt_entry = sgi_pt_types; pt_entry->pt_name; pt_entry++) {
196 if (pt_type == pt_entry->pt_type) break;
197 }
198#ifdef DEBUG
199 if (be32_to_cpu(vh->vh_pt[i].pt_nblks)) {
200 printk(KERN_DEBUG "EFS: pt %2d: start: %08d size: %08d type: 0x%02x (%s)\n",
201 i,
202 (int) be32_to_cpu(vh->vh_pt[i].pt_firstlbn),
203 (int) be32_to_cpu(vh->vh_pt[i].pt_nblks),
204 pt_type,
205 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown");
206 }
207#endif
208 if (IS_EFS(pt_type)) {
209 sblock = be32_to_cpu(vh->vh_pt[i].pt_firstlbn);
210 slice = i;
211 }
212 }
213
214 if (slice == -1) {
215 printk(KERN_NOTICE "EFS: partition table contained no EFS partitions\n");
216#ifdef DEBUG
217 } else {
218 printk(KERN_INFO "EFS: using slice %d (type %s, offset 0x%x)\n",
219 slice,
220 (pt_entry->pt_name) ? pt_entry->pt_name : "unknown",
221 sblock);
222#endif
223 }
Jesper Juhl014c2542006-01-15 02:37:08 +0100224 return sblock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225}
226
227static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
228
Jesper Juhl014c2542006-01-15 02:37:08 +0100229 if (!IS_EFS_MAGIC(be32_to_cpu(super->fs_magic)))
230 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231
232 sb->fs_magic = be32_to_cpu(super->fs_magic);
233 sb->total_blocks = be32_to_cpu(super->fs_size);
234 sb->first_block = be32_to_cpu(super->fs_firstcg);
235 sb->group_size = be32_to_cpu(super->fs_cgfsize);
236 sb->data_free = be32_to_cpu(super->fs_tfree);
237 sb->inode_free = be32_to_cpu(super->fs_tinode);
238 sb->inode_blocks = be16_to_cpu(super->fs_cgisize);
239 sb->total_groups = be16_to_cpu(super->fs_ncg);
240
241 return 0;
242}
243
244static int efs_fill_super(struct super_block *s, void *d, int silent)
245{
246 struct efs_sb_info *sb;
247 struct buffer_head *bh;
248 struct inode *root;
249
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -0700250 sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 if (!sb)
252 return -ENOMEM;
253 s->s_fs_info = sb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254
255 s->s_magic = EFS_SUPER_MAGIC;
256 if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
257 printk(KERN_ERR "EFS: device does not support %d byte blocks\n",
258 EFS_BLOCKSIZE);
259 goto out_no_fs_ul;
260 }
261
262 /* read the vh (volume header) block */
263 bh = sb_bread(s, 0);
264
265 if (!bh) {
266 printk(KERN_ERR "EFS: cannot read volume header\n");
267 goto out_no_fs_ul;
268 }
269
270 /*
271 * if this returns zero then we didn't find any partition table.
272 * this isn't (yet) an error - just assume for the moment that
273 * the device is valid and go on to search for a superblock.
274 */
275 sb->fs_start = efs_validate_vh((struct volume_header *) bh->b_data);
276 brelse(bh);
277
278 if (sb->fs_start == -1) {
279 goto out_no_fs_ul;
280 }
281
282 bh = sb_bread(s, sb->fs_start + EFS_SUPER);
283 if (!bh) {
284 printk(KERN_ERR "EFS: cannot read superblock\n");
285 goto out_no_fs_ul;
286 }
287
288 if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
289#ifdef DEBUG
290 printk(KERN_WARNING "EFS: invalid superblock at block %u\n", sb->fs_start + EFS_SUPER);
291#endif
292 brelse(bh);
293 goto out_no_fs_ul;
294 }
295 brelse(bh);
296
297 if (!(s->s_flags & MS_RDONLY)) {
298#ifdef DEBUG
299 printk(KERN_INFO "EFS: forcing read-only mode\n");
300#endif
301 s->s_flags |= MS_RDONLY;
302 }
303 s->s_op = &efs_superblock_operations;
304 s->s_export_op = &efs_export_ops;
305 root = iget(s, EFS_ROOTINODE);
306 s->s_root = d_alloc_root(root);
307
308 if (!(s->s_root)) {
309 printk(KERN_ERR "EFS: get root inode failed\n");
310 iput(root);
311 goto out_no_fs;
312 }
313
314 return 0;
315
316out_no_fs_ul:
317out_no_fs:
318 s->s_fs_info = NULL;
319 kfree(sb);
320 return -EINVAL;
321}
322
David Howells726c3342006-06-23 02:02:58 -0700323static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
324 struct efs_sb_info *sb = SUPER_INFO(dentry->d_sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
326 buf->f_type = EFS_SUPER_MAGIC; /* efs magic number */
327 buf->f_bsize = EFS_BLOCKSIZE; /* blocksize */
328 buf->f_blocks = sb->total_groups * /* total data blocks */
329 (sb->group_size - sb->inode_blocks);
330 buf->f_bfree = sb->data_free; /* free data blocks */
331 buf->f_bavail = sb->data_free; /* free blocks for non-root */
332 buf->f_files = sb->total_groups * /* total inodes */
333 sb->inode_blocks *
334 (EFS_BLOCKSIZE / sizeof(struct efs_dinode));
335 buf->f_ffree = sb->inode_free; /* free inodes */
336 buf->f_fsid.val[0] = (sb->fs_magic >> 16) & 0xffff; /* fs ID */
337 buf->f_fsid.val[1] = sb->fs_magic & 0xffff; /* fs ID */
338 buf->f_namelen = EFS_MAXNAMELEN; /* max filename length */
339
340 return 0;
341}
342