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15#include <linux/mtd/super.h>
16#include <linux/namei.h>
17#include <linux/export.h>
18#include <linux/ctype.h>
19#include <linux/slab.h>
20
21
22
23
24
25static int get_sb_mtd_compare(struct super_block *sb, void *_mtd)
26{
27 struct mtd_info *mtd = _mtd;
28
29 if (sb->s_mtd == mtd) {
30 pr_debug("MTDSB: Match on device %d (\"%s\")\n",
31 mtd->index, mtd->name);
32 return 1;
33 }
34
35 pr_debug("MTDSB: No match, device %d (\"%s\"), device %d (\"%s\")\n",
36 sb->s_mtd->index, sb->s_mtd->name, mtd->index, mtd->name);
37 return 0;
38}
39
40
41
42
43
44
45static int get_sb_mtd_set(struct super_block *sb, void *_mtd)
46{
47 struct mtd_info *mtd = _mtd;
48
49 sb->s_mtd = mtd;
50 sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, mtd->index);
51 sb->s_bdi = mtd->backing_dev_info;
52 return 0;
53}
54
55
56
57
58static struct dentry *mount_mtd_aux(struct file_system_type *fs_type, int flags,
59 const char *dev_name, void *data,
60 struct mtd_info *mtd,
61 int (*fill_super)(struct super_block *, void *, int))
62{
63 struct super_block *sb;
64 int ret;
65
66 sb = sget(fs_type, get_sb_mtd_compare, get_sb_mtd_set, flags, mtd);
67 if (IS_ERR(sb))
68 goto out_error;
69
70 if (sb->s_root)
71 goto already_mounted;
72
73
74 pr_debug("MTDSB: New superblock for device %d (\"%s\")\n",
75 mtd->index, mtd->name);
76
77 ret = fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
78 if (ret < 0) {
79 deactivate_locked_super(sb);
80 return ERR_PTR(ret);
81 }
82
83
84 sb->s_flags |= MS_ACTIVE;
85 return dget(sb->s_root);
86
87
88already_mounted:
89 pr_debug("MTDSB: Device %d (\"%s\") is already mounted\n",
90 mtd->index, mtd->name);
91 put_mtd_device(mtd);
92 return dget(sb->s_root);
93
94out_error:
95 put_mtd_device(mtd);
96 return ERR_CAST(sb);
97}
98
99
100
101
102static struct dentry *mount_mtd_nr(struct file_system_type *fs_type, int flags,
103 const char *dev_name, void *data, int mtdnr,
104 int (*fill_super)(struct super_block *, void *, int))
105{
106 struct mtd_info *mtd;
107
108 mtd = get_mtd_device(NULL, mtdnr);
109 if (IS_ERR(mtd)) {
110 pr_debug("MTDSB: Device #%u doesn't appear to exist\n", mtdnr);
111 return ERR_CAST(mtd);
112 }
113
114 return mount_mtd_aux(fs_type, flags, dev_name, data, mtd, fill_super);
115}
116
117
118
119
120struct dentry *mount_mtd(struct file_system_type *fs_type, int flags,
121 const char *dev_name, void *data,
122 int (*fill_super)(struct super_block *, void *, int))
123{
124#ifdef CONFIG_BLOCK
125 struct block_device *bdev;
126 int ret, major;
127#endif
128 int mtdnr;
129
130 if (!dev_name)
131 return ERR_PTR(-EINVAL);
132
133 pr_debug("MTDSB: dev_name \"%s\"\n", dev_name);
134
135
136
137
138
139 if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') {
140 if (dev_name[3] == ':') {
141 struct mtd_info *mtd;
142
143
144 pr_debug("MTDSB: mtd:%%s, name \"%s\"\n",
145 dev_name + 4);
146
147 mtd = get_mtd_device_nm(dev_name + 4);
148 if (!IS_ERR(mtd))
149 return mount_mtd_aux(
150 fs_type, flags,
151 dev_name, data, mtd,
152 fill_super);
153
154 printk(KERN_NOTICE "MTD:"
155 " MTD device with name \"%s\" not found.\n",
156 dev_name + 4);
157
158 } else if (isdigit(dev_name[3])) {
159
160 char *endptr;
161
162 mtdnr = simple_strtoul(dev_name + 3, &endptr, 0);
163 if (!*endptr) {
164
165 pr_debug("MTDSB: mtd%%d, mtdnr %d\n",
166 mtdnr);
167 return mount_mtd_nr(fs_type, flags,
168 dev_name, data,
169 mtdnr, fill_super);
170 }
171 }
172 }
173
174#ifdef CONFIG_BLOCK
175
176
177
178 bdev = lookup_bdev(dev_name);
179 if (IS_ERR(bdev)) {
180 ret = PTR_ERR(bdev);
181 pr_debug("MTDSB: lookup_bdev() returned %d\n", ret);
182 return ERR_PTR(ret);
183 }
184 pr_debug("MTDSB: lookup_bdev() returned 0\n");
185
186 ret = -EINVAL;
187
188 major = MAJOR(bdev->bd_dev);
189 mtdnr = MINOR(bdev->bd_dev);
190 bdput(bdev);
191
192 if (major != MTD_BLOCK_MAJOR)
193 goto not_an_MTD_device;
194
195 return mount_mtd_nr(fs_type, flags, dev_name, data, mtdnr, fill_super);
196
197not_an_MTD_device:
198#endif
199
200 if (!(flags & MS_SILENT))
201 printk(KERN_NOTICE
202 "MTD: Attempt to mount non-MTD device \"%s\"\n",
203 dev_name);
204 return ERR_PTR(-EINVAL);
205}
206
207EXPORT_SYMBOL_GPL(mount_mtd);
208
209
210
211
212void kill_mtd_super(struct super_block *sb)
213{
214 generic_shutdown_super(sb);
215 put_mtd_device(sb->s_mtd);
216 sb->s_mtd = NULL;
217}
218
219EXPORT_SYMBOL_GPL(kill_mtd_super);
220