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-rw-r--r--drivers/mtd/Makefile3
-rw-r--r--drivers/mtd/mtdsuper.c232
-rw-r--r--fs/jffs2/super.c194
-rw-r--r--include/linux/fs.h1
-rw-r--r--include/linux/mtd/super.h30
5 files changed, 283 insertions, 177 deletions
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index 92055405cb30..451adcc52b3c 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -1,10 +1,9 @@
1# 1#
2# Makefile for the memory technology device drivers. 2# Makefile for the memory technology device drivers.
3# 3#
4# $Id: Makefile.common,v 1.7 2005/07/11 10:39:27 gleixner Exp $
5 4
6# Core functionality. 5# Core functionality.
7mtd-y := mtdcore.o 6mtd-y := mtdcore.o mtdsuper.o
8mtd-$(CONFIG_MTD_PARTITIONS) += mtdpart.o 7mtd-$(CONFIG_MTD_PARTITIONS) += mtdpart.o
9obj-$(CONFIG_MTD) += $(mtd-y) 8obj-$(CONFIG_MTD) += $(mtd-y)
10 9
diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c
new file mode 100644
index 000000000000..a279540ba87a
--- /dev/null
+++ b/drivers/mtd/mtdsuper.c
@@ -0,0 +1,232 @@
1/* MTD-based superblock management
2 *
3 * Copyright © 2001-2007 Red Hat, Inc. All Rights Reserved.
4 * Written by: David Howells <dhowells@redhat.com>
5 * David Woodhouse <dwmw2@infradead.org>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#include <linux/mtd/super.h>
14#include <linux/namei.h>
15#include <linux/ctype.h>
16
17/*
18 * compare superblocks to see if they're equivalent
19 * - they are if the underlying MTD device is the same
20 */
21static int get_sb_mtd_compare(struct super_block *sb, void *_mtd)
22{
23 struct mtd_info *mtd = _mtd;
24
25 if (sb->s_mtd == mtd) {
26 DEBUG(2, "MTDSB: Match on device %d (\"%s\")\n",
27 mtd->index, mtd->name);
28 return 1;
29 }
30
31 DEBUG(2, "MTDSB: No match, device %d (\"%s\"), device %d (\"%s\")\n",
32 sb->s_mtd->index, sb->s_mtd->name, mtd->index, mtd->name);
33 return 0;
34}
35
36/*
37 * mark the superblock by the MTD device it is using
38 * - set the device number to be the correct MTD block device for pesuperstence
39 * of NFS exports
40 */
41static int get_sb_mtd_set(struct super_block *sb, void *_mtd)
42{
43 struct mtd_info *mtd = _mtd;
44
45 sb->s_mtd = mtd;
46 sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, mtd->index);
47 return 0;
48}
49
50/*
51 * get a superblock on an MTD-backed filesystem
52 */
53static int get_sb_mtd_aux(struct file_system_type *fs_type, int flags,
54 const char *dev_name, void *data,
55 struct mtd_info *mtd,
56 int (*fill_super)(struct super_block *, void *, int),
57 struct vfsmount *mnt)
58{
59 struct super_block *sb;
60 int ret;
61
62 sb = sget(fs_type, get_sb_mtd_compare, get_sb_mtd_set, mtd);
63 if (IS_ERR(sb))
64 goto out_error;
65
66 if (sb->s_root)
67 goto already_mounted;
68
69 /* fresh new superblock */
70 DEBUG(1, "MTDSB: New superblock for device %d (\"%s\")\n",
71 mtd->index, mtd->name);
72
73 ret = fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
74 if (ret < 0) {
75 up_write(&sb->s_umount);
76 deactivate_super(sb);
77 return ret;
78 }
79
80 /* go */
81 sb->s_flags |= MS_ACTIVE;
82 return simple_set_mnt(mnt, sb);
83
84 /* new mountpoint for an already mounted superblock */
85already_mounted:
86 DEBUG(1, "MTDSB: Device %d (\"%s\") is already mounted\n",
87 mtd->index, mtd->name);
88 ret = simple_set_mnt(mnt, sb);
89 goto out_put;
90
91out_error:
92 ret = PTR_ERR(sb);
93out_put:
94 put_mtd_device(mtd);
95 return ret;
96}
97
98/*
99 * get a superblock on an MTD-backed filesystem by MTD device number
100 */
101static int get_sb_mtd_nr(struct file_system_type *fs_type, int flags,
102 const char *dev_name, void *data, int mtdnr,
103 int (*fill_super)(struct super_block *, void *, int),
104 struct vfsmount *mnt)
105{
106 struct mtd_info *mtd;
107
108 mtd = get_mtd_device(NULL, mtdnr);
109 if (!mtd) {
110 DEBUG(0, "MTDSB: Device #%u doesn't appear to exist\n", mtdnr);
111 return -EINVAL;
112 }
113
114 return get_sb_mtd_aux(fs_type, flags, dev_name, data, mtd, fill_super,
115 mnt);
116}
117
118/*
119 * set up an MTD-based superblock
120 */
121int get_sb_mtd(struct file_system_type *fs_type, int flags,
122 const char *dev_name, void *data,
123 int (*fill_super)(struct super_block *, void *, int),
124 struct vfsmount *mnt)
125{
126 struct nameidata nd;
127 int mtdnr, ret;
128
129 if (!dev_name)
130 return -EINVAL;
131
132 DEBUG(2, "MTDSB: dev_name \"%s\"\n", dev_name);
133
134 /* the preferred way of mounting in future; especially when
135 * CONFIG_BLOCK=n - we specify the underlying MTD device by number or
136 * by name, so that we don't require block device support to be present
137 * in the kernel. */
138 if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') {
139 if (dev_name[3] == ':') {
140 struct mtd_info *mtd;
141
142 /* mount by MTD device name */
143 DEBUG(1, "MTDSB: mtd:%%s, name \"%s\"\n",
144 dev_name + 4);
145
146 for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) {
147 mtd = get_mtd_device(NULL, mtdnr);
148 if (mtd) {
149 if (!strcmp(mtd->name, dev_name + 4))
150 return get_sb_mtd_aux(
151 fs_type, flags,
152 dev_name, data, mtd,
153 fill_super, mnt);
154
155 put_mtd_device(mtd);
156 }
157 }
158
159 printk(KERN_NOTICE "MTD:"
160 " MTD device with name \"%s\" not found.\n",
161 dev_name + 4);
162
163 } else if (isdigit(dev_name[3])) {
164 /* mount by MTD device number name */
165 char *endptr;
166
167 mtdnr = simple_strtoul(dev_name + 3, &endptr, 0);
168 if (!*endptr) {
169 /* It was a valid number */
170 DEBUG(1, "MTDSB: mtd%%d, mtdnr %d\n",
171 mtdnr);
172 return get_sb_mtd_nr(fs_type, flags,
173 dev_name, data,
174 mtdnr, fill_super, mnt);
175 }
176 }
177 }
178
179 /* try the old way - the hack where we allowed users to mount
180 * /dev/mtdblock$(n) but didn't actually _use_ the blockdev
181 */
182 ret = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
183
184 DEBUG(1, "MTDSB: path_lookup() returned %d, inode %p\n",
185 ret, nd.dentry ? nd.dentry->d_inode : NULL);
186
187 if (ret)
188 return ret;
189
190 ret = -EINVAL;
191
192 if (!S_ISBLK(nd.dentry->d_inode->i_mode))
193 goto out;
194
195 if (nd.mnt->mnt_flags & MNT_NODEV) {
196 ret = -EACCES;
197 goto out;
198 }
199
200 if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR)
201 goto not_an_MTD_device;
202
203 mtdnr = iminor(nd.dentry->d_inode);
204 path_release(&nd);
205
206 return get_sb_mtd_nr(fs_type, flags, dev_name, data, mtdnr, fill_super,
207 mnt);
208
209not_an_MTD_device:
210 if (!(flags & MS_SILENT))
211 printk(KERN_NOTICE
212 "MTD: Attempt to mount non-MTD device \"%s\"\n",
213 dev_name);
214out:
215 path_release(&nd);
216 return ret;
217
218}
219
220EXPORT_SYMBOL_GPL(get_sb_mtd);
221
222/*
223 * destroy an MTD-based superblock
224 */
225void kill_mtd_super(struct super_block *sb)
226{
227 generic_shutdown_super(sb);
228 put_mtd_device(sb->s_mtd);
229 sb->s_mtd = NULL;
230}
231
232EXPORT_SYMBOL_GPL(kill_mtd_super);
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index e51164a8a8d4..e3c69e659efb 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -19,7 +19,7 @@
19#include <linux/mount.h> 19#include <linux/mount.h>
20#include <linux/jffs2.h> 20#include <linux/jffs2.h>
21#include <linux/pagemap.h> 21#include <linux/pagemap.h>
22#include <linux/mtd/mtd.h> 22#include <linux/mtd/super.h>
23#include <linux/ctype.h> 23#include <linux/ctype.h>
24#include <linux/namei.h> 24#include <linux/namei.h>
25#include "compr.h" 25#include "compr.h"
@@ -78,69 +78,27 @@ static const struct super_operations jffs2_super_operations =
78 .sync_fs = jffs2_sync_fs, 78 .sync_fs = jffs2_sync_fs,
79}; 79};
80 80
81static int jffs2_sb_compare(struct super_block *sb, void *data) 81/*
82{ 82 * fill in the superblock
83 struct jffs2_sb_info *p = data; 83 */
84 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); 84static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
85
86 /* The superblocks are considered to be equivalent if the underlying MTD
87 device is the same one */
88 if (c->mtd == p->mtd) {
89 D1(printk(KERN_DEBUG "jffs2_sb_compare: match on device %d (\"%s\")\n", p->mtd->index, p->mtd->name));
90 return 1;
91 } else {
92 D1(printk(KERN_DEBUG "jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n",
93 c->mtd->index, c->mtd->name, p->mtd->index, p->mtd->name));
94 return 0;
95 }
96}
97
98static int jffs2_sb_set(struct super_block *sb, void *data)
99{
100 struct jffs2_sb_info *p = data;
101
102 /* For persistence of NFS exports etc. we use the same s_dev
103 each time we mount the device, don't just use an anonymous
104 device */
105 sb->s_fs_info = p;
106 p->os_priv = sb;
107 sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, p->mtd->index);
108
109 return 0;
110}
111
112static int jffs2_get_sb_mtd(struct file_system_type *fs_type,
113 int flags, const char *dev_name,
114 void *data, struct mtd_info *mtd,
115 struct vfsmount *mnt)
116{ 85{
117 struct super_block *sb;
118 struct jffs2_sb_info *c; 86 struct jffs2_sb_info *c;
119 int ret; 87
88 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
89 " New superblock for device %d (\"%s\")\n",
90 sb->s_mtd->index, sb->s_mtd->name));
120 91
121 c = kzalloc(sizeof(*c), GFP_KERNEL); 92 c = kzalloc(sizeof(*c), GFP_KERNEL);
122 if (!c) 93 if (!c)
123 return -ENOMEM; 94 return -ENOMEM;
124 c->mtd = mtd;
125
126 sb = sget(fs_type, jffs2_sb_compare, jffs2_sb_set, c);
127
128 if (IS_ERR(sb))
129 goto out_error;
130
131 if (sb->s_root) {
132 /* New mountpoint for JFFS2 which is already mounted */
133 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n",
134 mtd->index, mtd->name));
135 ret = simple_set_mnt(mnt, sb);
136 goto out_put;
137 }
138 95
139 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n", 96 c->mtd = sb->s_mtd;
140 mtd->index, mtd->name)); 97 c->os_priv = sb;
98 sb->s_fs_info = c;
141 99
142 /* Initialize JFFS2 superblock locks, the further initialization will be 100 /* Initialize JFFS2 superblock locks, the further initialization will
143 * done later */ 101 * be done later */
144 init_MUTEX(&c->alloc_sem); 102 init_MUTEX(&c->alloc_sem);
145 init_MUTEX(&c->erase_free_sem); 103 init_MUTEX(&c->erase_free_sem);
146 init_waitqueue_head(&c->erase_wait); 104 init_waitqueue_head(&c->erase_wait);
@@ -149,133 +107,20 @@ static int jffs2_get_sb_mtd(struct file_system_type *fs_type,
149 spin_lock_init(&c->inocache_lock); 107 spin_lock_init(&c->inocache_lock);
150 108
151 sb->s_op = &jffs2_super_operations; 109 sb->s_op = &jffs2_super_operations;
152 sb->s_flags = flags | MS_NOATIME; 110 sb->s_flags = sb->s_flags | MS_NOATIME;
153 sb->s_xattr = jffs2_xattr_handlers; 111 sb->s_xattr = jffs2_xattr_handlers;
154#ifdef CONFIG_JFFS2_FS_POSIX_ACL 112#ifdef CONFIG_JFFS2_FS_POSIX_ACL
155 sb->s_flags |= MS_POSIXACL; 113 sb->s_flags |= MS_POSIXACL;
156#endif 114#endif
157 ret = jffs2_do_fill_super(sb, data, flags & MS_SILENT ? 1 : 0); 115 return jffs2_do_fill_super(sb, data, silent);
158
159 if (ret) {
160 /* Failure case... */
161 up_write(&sb->s_umount);
162 deactivate_super(sb);
163 return ret;
164 }
165
166 sb->s_flags |= MS_ACTIVE;
167 return simple_set_mnt(mnt, sb);
168
169out_error:
170 ret = PTR_ERR(sb);
171 out_put:
172 kfree(c);
173 put_mtd_device(mtd);
174
175 return ret;
176}
177
178static int jffs2_get_sb_mtdnr(struct file_system_type *fs_type,
179 int flags, const char *dev_name,
180 void *data, int mtdnr,
181 struct vfsmount *mnt)
182{
183 struct mtd_info *mtd;
184
185 mtd = get_mtd_device(NULL, mtdnr);
186 if (IS_ERR(mtd)) {
187 D1(printk(KERN_DEBUG "jffs2: MTD device #%u doesn't appear to exist\n", mtdnr));
188 return PTR_ERR(mtd);
189 }
190
191 return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt);
192} 116}
193 117
194static int jffs2_get_sb(struct file_system_type *fs_type, 118static int jffs2_get_sb(struct file_system_type *fs_type,
195 int flags, const char *dev_name, 119 int flags, const char *dev_name,
196 void *data, struct vfsmount *mnt) 120 void *data, struct vfsmount *mnt)
197{ 121{
198 int err; 122 return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
199 struct nameidata nd; 123 mnt);
200 int mtdnr;
201
202 if (!dev_name)
203 return -EINVAL;
204
205 D1(printk(KERN_DEBUG "jffs2_get_sb(): dev_name \"%s\"\n", dev_name));
206
207 /* The preferred way of mounting in future; especially when
208 CONFIG_BLK_DEV is implemented - we specify the underlying
209 MTD device by number or by name, so that we don't require
210 block device support to be present in the kernel. */
211
212 /* FIXME: How to do the root fs this way? */
213
214 if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') {
215 /* Probably mounting without the blkdev crap */
216 if (dev_name[3] == ':') {
217 struct mtd_info *mtd;
218
219 /* Mount by MTD device name */
220 D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name+4));
221 for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) {
222 mtd = get_mtd_device(NULL, mtdnr);
223 if (!IS_ERR(mtd)) {
224 if (!strcmp(mtd->name, dev_name+4))
225 return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt);
226 put_mtd_device(mtd);
227 }
228 }
229 printk(KERN_NOTICE "jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name+4);
230 } else if (isdigit(dev_name[3])) {
231 /* Mount by MTD device number name */
232 char *endptr;
233
234 mtdnr = simple_strtoul(dev_name+3, &endptr, 0);
235 if (!*endptr) {
236 /* It was a valid number */
237 D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr));
238 return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt);
239 }
240 }
241 }
242
243 /* Try the old way - the hack where we allowed users to mount
244 /dev/mtdblock$(n) but didn't actually _use_ the blkdev */
245
246 err = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
247
248 D1(printk(KERN_DEBUG "jffs2_get_sb(): path_lookup() returned %d, inode %p\n",
249 err, nd.dentry->d_inode));
250
251 if (err)
252 return err;
253
254 err = -EINVAL;
255
256 if (!S_ISBLK(nd.dentry->d_inode->i_mode))
257 goto out;
258
259 if (nd.mnt->mnt_flags & MNT_NODEV) {
260 err = -EACCES;
261 goto out;
262 }
263
264 if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR) {
265 if (!(flags & MS_SILENT))
266 printk(KERN_NOTICE "Attempt to mount non-MTD device \"%s\" as JFFS2\n",
267 dev_name);
268 goto out;
269 }
270
271 mtdnr = iminor(nd.dentry->d_inode);
272 path_release(&nd);
273
274 return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt);
275
276out:
277 path_release(&nd);
278 return err;
279} 124}
280 125
281static void jffs2_put_super (struct super_block *sb) 126static void jffs2_put_super (struct super_block *sb)
@@ -310,8 +155,7 @@ static void jffs2_kill_sb(struct super_block *sb)
310 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); 155 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
311 if (!(sb->s_flags & MS_RDONLY)) 156 if (!(sb->s_flags & MS_RDONLY))
312 jffs2_stop_garbage_collect_thread(c); 157 jffs2_stop_garbage_collect_thread(c);
313 generic_shutdown_super(sb); 158 kill_mtd_super(sb);
314 put_mtd_device(c->mtd);
315 kfree(c); 159 kfree(c);
316} 160}
317 161
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 095a9c9a64fb..151739a55eaf 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -937,6 +937,7 @@ struct super_block {
937 struct list_head s_files; 937 struct list_head s_files;
938 938
939 struct block_device *s_bdev; 939 struct block_device *s_bdev;
940 struct mtd_info *s_mtd;
940 struct list_head s_instances; 941 struct list_head s_instances;
941 struct quota_info s_dquot; /* Diskquota specific options */ 942 struct quota_info s_dquot; /* Diskquota specific options */
942 943
diff --git a/include/linux/mtd/super.h b/include/linux/mtd/super.h
new file mode 100644
index 000000000000..4016dd6fe336
--- /dev/null
+++ b/include/linux/mtd/super.h
@@ -0,0 +1,30 @@
1/* MTD-based superblock handling
2 *
3 * Copyright © 2006 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#ifndef __MTD_SUPER_H__
13#define __MTD_SUPER_H__
14
15#ifdef __KERNEL__
16
17#include <linux/mtd/mtd.h>
18#include <linux/fs.h>
19#include <linux/mount.h>
20
21extern int get_sb_mtd(struct file_system_type *fs_type, int flags,
22 const char *dev_name, void *data,
23 int (*fill_super)(struct super_block *, void *, int),
24 struct vfsmount *mnt);
25extern void kill_mtd_super(struct super_block *sb);
26
27
28#endif /* __KERNEL__ */
29
30#endif /* __MTD_SUPER_H__ */
generated by cgit v1.2.2 (git 2.25.0) at 2025-12-01 18:43:48 -0500