1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright © 2001-2007 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <dwmw2@infradead.org> 7 * 8 * For licensing information, see the file 'LICENCE' in this directory. 9 * 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/slab.h> 15 #include <linux/init.h> 16 #include <linux/list.h> 17 #include <linux/fs.h> 18 #include <linux/err.h> 19 #include <linux/mount.h> 20 #include <linux/jffs2.h> 21 #include <linux/pagemap.h> 22 #include <linux/mtd/super.h> 23 #include <linux/ctype.h> 24 #include <linux/namei.h> 25 #include <linux/exportfs.h> 26 #include "compr.h" 27 #include "nodelist.h" 28 29 static void jffs2_put_super(struct super_block *); 30 31 static struct kmem_cache *jffs2_inode_cachep; 32 33 static struct inode *jffs2_alloc_inode(struct super_block *sb) 34 { 35 struct jffs2_inode_info *f; 36 37 f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL); 38 if (!f) 39 return NULL; 40 return &f->vfs_inode; 41 } 42 43 static void jffs2_destroy_inode(struct inode *inode) 44 { 45 kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode)); 46 } 47 48 static void jffs2_i_init_once(void *foo) 49 { 50 struct jffs2_inode_info *f = foo; 51 52 mutex_init(&f->sem); 53 inode_init_once(&f->vfs_inode); 54 } 55 56 static int jffs2_sync_fs(struct super_block *sb, int wait) 57 { 58 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); 59 60 mutex_lock(&c->alloc_sem); 61 jffs2_flush_wbuf_pad(c); 62 mutex_unlock(&c->alloc_sem); 63 return 0; 64 } 65 66 static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, 67 uint32_t generation) 68 { 69 /* We don't care about i_generation. We'll destroy the flash 70 before we start re-using inode numbers anyway. And even 71 if that wasn't true, we'd have other problems...*/ 72 return jffs2_iget(sb, ino); 73 } 74 75 static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, 76 int fh_len, int fh_type) 77 { 78 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 79 jffs2_nfs_get_inode); 80 } 81 82 static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid, 83 int fh_len, int fh_type) 84 { 85 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 86 jffs2_nfs_get_inode); 87 } 88 89 static struct dentry *jffs2_get_parent(struct dentry *child) 90 { 91 struct jffs2_inode_info *f; 92 uint32_t pino; 93 94 BUG_ON(!S_ISDIR(child->d_inode->i_mode)); 95 96 f = JFFS2_INODE_INFO(child->d_inode); 97 98 pino = f->inocache->pino_nlink; 99 100 JFFS2_DEBUG("Parent of directory ino #%u is #%u\n", 101 f->inocache->ino, pino); 102 103 return d_obtain_alias(jffs2_iget(child->d_inode->i_sb, pino)); 104 } 105 106 static struct export_operations jffs2_export_ops = { 107 .get_parent = jffs2_get_parent, 108 .fh_to_dentry = jffs2_fh_to_dentry, 109 .fh_to_parent = jffs2_fh_to_parent, 110 }; 111 112 static const struct super_operations jffs2_super_operations = 113 { 114 .alloc_inode = jffs2_alloc_inode, 115 .destroy_inode =jffs2_destroy_inode, 116 .put_super = jffs2_put_super, 117 .write_super = jffs2_write_super, 118 .statfs = jffs2_statfs, 119 .remount_fs = jffs2_remount_fs, 120 .clear_inode = jffs2_clear_inode, 121 .dirty_inode = jffs2_dirty_inode, 122 .sync_fs = jffs2_sync_fs, 123 }; 124 125 /* 126 * fill in the superblock 127 */ 128 static int jffs2_fill_super(struct super_block *sb, void *data, int silent) 129 { 130 struct jffs2_sb_info *c; 131 132 D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():" 133 " New superblock for device %d (\"%s\")\n", 134 sb->s_mtd->index, sb->s_mtd->name)); 135 136 c = kzalloc(sizeof(*c), GFP_KERNEL); 137 if (!c) 138 return -ENOMEM; 139 140 c->mtd = sb->s_mtd; 141 c->os_priv = sb; 142 sb->s_fs_info = c; 143 144 /* Initialize JFFS2 superblock locks, the further initialization will 145 * be done later */ 146 mutex_init(&c->alloc_sem); 147 mutex_init(&c->erase_free_sem); 148 init_waitqueue_head(&c->erase_wait); 149 init_waitqueue_head(&c->inocache_wq); 150 spin_lock_init(&c->erase_completion_lock); 151 spin_lock_init(&c->inocache_lock); 152 153 sb->s_op = &jffs2_super_operations; 154 sb->s_export_op = &jffs2_export_ops; 155 sb->s_flags = sb->s_flags | MS_NOATIME; 156 sb->s_xattr = jffs2_xattr_handlers; 157 #ifdef CONFIG_JFFS2_FS_POSIX_ACL 158 sb->s_flags |= MS_POSIXACL; 159 #endif 160 return jffs2_do_fill_super(sb, data, silent); 161 } 162 163 static int jffs2_get_sb(struct file_system_type *fs_type, 164 int flags, const char *dev_name, 165 void *data, struct vfsmount *mnt) 166 { 167 return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super, 168 mnt); 169 } 170 171 static void jffs2_put_super (struct super_block *sb) 172 { 173 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); 174 175 D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n")); 176 177 mutex_lock(&c->alloc_sem); 178 jffs2_flush_wbuf_pad(c); 179 mutex_unlock(&c->alloc_sem); 180 181 jffs2_sum_exit(c); 182 183 jffs2_free_ino_caches(c); 184 jffs2_free_raw_node_refs(c); 185 if (jffs2_blocks_use_vmalloc(c)) 186 vfree(c->blocks); 187 else 188 kfree(c->blocks); 189 jffs2_flash_cleanup(c); 190 kfree(c->inocache_list); 191 jffs2_clear_xattr_subsystem(c); 192 if (c->mtd->sync) 193 c->mtd->sync(c->mtd); 194 195 D1(printk(KERN_DEBUG "jffs2_put_super returning\n")); 196 } 197 198 static void jffs2_kill_sb(struct super_block *sb) 199 { 200 struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); 201 if (!(sb->s_flags & MS_RDONLY)) 202 jffs2_stop_garbage_collect_thread(c); 203 kill_mtd_super(sb); 204 kfree(c); 205 } 206 207 static struct file_system_type jffs2_fs_type = { 208 .owner = THIS_MODULE, 209 .name = "jffs2", 210 .get_sb = jffs2_get_sb, 211 .kill_sb = jffs2_kill_sb, 212 }; 213 214 static int __init init_jffs2_fs(void) 215 { 216 int ret; 217 218 /* Paranoia checks for on-medium structures. If we ask GCC 219 to pack them with __attribute__((packed)) then it _also_ 220 assumes that they're not aligned -- so it emits crappy 221 code on some architectures. Ideally we want an attribute 222 which means just 'no padding', without the alignment 223 thing. But GCC doesn't have that -- we have to just 224 hope the structs are the right sizes, instead. */ 225 BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12); 226 BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40); 227 BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68); 228 BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32); 229 230 printk(KERN_INFO "JFFS2 version 2.2." 231 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 232 " (NAND)" 233 #endif 234 #ifdef CONFIG_JFFS2_SUMMARY 235 " (SUMMARY) " 236 #endif 237 " © 2001-2006 Red Hat, Inc.\n"); 238 239 jffs2_inode_cachep = kmem_cache_create("jffs2_i", 240 sizeof(struct jffs2_inode_info), 241 0, (SLAB_RECLAIM_ACCOUNT| 242 SLAB_MEM_SPREAD), 243 jffs2_i_init_once); 244 if (!jffs2_inode_cachep) { 245 printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n"); 246 return -ENOMEM; 247 } 248 ret = jffs2_compressors_init(); 249 if (ret) { 250 printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n"); 251 goto out; 252 } 253 ret = jffs2_create_slab_caches(); 254 if (ret) { 255 printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n"); 256 goto out_compressors; 257 } 258 ret = register_filesystem(&jffs2_fs_type); 259 if (ret) { 260 printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n"); 261 goto out_slab; 262 } 263 return 0; 264 265 out_slab: 266 jffs2_destroy_slab_caches(); 267 out_compressors: 268 jffs2_compressors_exit(); 269 out: 270 kmem_cache_destroy(jffs2_inode_cachep); 271 return ret; 272 } 273 274 static void __exit exit_jffs2_fs(void) 275 { 276 unregister_filesystem(&jffs2_fs_type); 277 jffs2_destroy_slab_caches(); 278 jffs2_compressors_exit(); 279 kmem_cache_destroy(jffs2_inode_cachep); 280 } 281 282 module_init(init_jffs2_fs); 283 module_exit(exit_jffs2_fs); 284 285 MODULE_DESCRIPTION("The Journalling Flash File System, v2"); 286 MODULE_AUTHOR("Red Hat, Inc."); 287 MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for 288 // the sake of this tag. It's Free Software. 289