/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright (C) 2001-2003 Red Hat, Inc. * * Created by David Woodhouse <dwmw2@infradead.org> * * For licensing information, see the file 'LICENCE' in this directory. * * $Id: super.c,v 1.110 2005/11/07 11:14:42 gleixner Exp $ * */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/list.h> #include <linux/fs.h> #include <linux/mount.h> #include <linux/jffs2.h> #include <linux/pagemap.h> #include <linux/mtd/mtd.h> #include <linux/ctype.h> #include <linux/namei.h> #include "compr.h" #include "nodelist.h" static void jffs2_put_super(struct super_block *); static kmem_cache_t *jffs2_inode_cachep; static struct inode *jffs2_alloc_inode(struct super_block *sb) { struct jffs2_inode_info *ei; ei = (struct jffs2_inode_info *)kmem_cache_alloc(jffs2_inode_cachep, SLAB_KERNEL); if (!ei) return NULL; return &ei->vfs_inode; } static void jffs2_destroy_inode(struct inode *inode) { kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode)); } static void jffs2_i_init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) { struct jffs2_inode_info *ei = (struct jffs2_inode_info *) foo; if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == SLAB_CTOR_CONSTRUCTOR) { init_MUTEX(&ei->sem); inode_init_once(&ei->vfs_inode); } } static int jffs2_sync_fs(struct super_block *sb, int wait) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); down(&c->alloc_sem); jffs2_flush_wbuf_pad(c); up(&c->alloc_sem); return 0; } static struct super_operations jffs2_super_operations = { .alloc_inode = jffs2_alloc_inode, .destroy_inode =jffs2_destroy_inode, .read_inode = jffs2_read_inode, .put_super = jffs2_put_super, .write_super = jffs2_write_super, .statfs = jffs2_statfs, .remount_fs = jffs2_remount_fs, .clear_inode = jffs2_clear_inode, .dirty_inode = jffs2_dirty_inode, .sync_fs = jffs2_sync_fs, }; static int jffs2_sb_compare(struct super_block *sb, void *data) { struct jffs2_sb_info *p = data; struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); /* The superblocks are considered to be equivalent if the underlying MTD device is the same one */ if (c->mtd == p->mtd) { D1(printk(KERN_DEBUG "jffs2_sb_compare: match on device %d (\"%s\")\n", p->mtd->index, p->mtd->name)); return 1; } else { D1(printk(KERN_DEBUG "jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n", c->mtd->index, c->mtd->name, p->mtd->index, p->mtd->name)); return 0; } } static int jffs2_sb_set(struct super_block *sb, void *data) { struct jffs2_sb_info *p = data; /* For persistence of NFS exports etc. we use the same s_dev each time we mount the device, don't just use an anonymous device */ sb->s_fs_info = p; p->os_priv = sb; sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, p->mtd->index); return 0; } static int jffs2_get_sb_mtd(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct mtd_info *mtd, struct vfsmount *mnt) { struct super_block *sb; struct jffs2_sb_info *c; int ret; c = kzalloc(sizeof(*c), GFP_KERNEL); if (!c) return -ENOMEM; c->mtd = mtd; sb = sget(fs_type, jffs2_sb_compare, jffs2_sb_set, c); if (IS_ERR(sb)) goto out_error; if (sb->s_root) { /* New mountpoint for JFFS2 which is already mounted */ D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n", mtd->index, mtd->name)); ret = simple_set_mnt(mnt, sb); goto out_put; } D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n", mtd->index, mtd->name)); /* Initialize JFFS2 superblock locks, the further initialization will be * done later */ init_MUTEX(&c->alloc_sem); init_MUTEX(&c->erase_free_sem); init_waitqueue_head(&c->erase_wait); init_waitqueue_head(&c->inocache_wq); spin_lock_init(&c->erase_completion_lock); spin_lock_init(&c->inocache_lock); sb->s_op = &jffs2_super_operations; sb->s_flags = flags | MS_NOATIME; sb->s_xattr = jffs2_xattr_handlers; #ifdef CONFIG_JFFS2_FS_POSIX_ACL sb->s_flags |= MS_POSIXACL; #endif ret = jffs2_do_fill_super(sb, data, flags & MS_SILENT ? 1 : 0); if (ret) { /* Failure case... */ up_write(&sb->s_umount); deactivate_super(sb); return ret; } sb->s_flags |= MS_ACTIVE; return simple_set_mnt(mnt, sb); out_error: ret = PTR_ERR(sb); out_put: kfree(c); put_mtd_device(mtd); return ret; } static int jffs2_get_sb_mtdnr(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, int mtdnr, struct vfsmount *mnt) { struct mtd_info *mtd; mtd = get_mtd_device(NULL, mtdnr); if (!mtd) { D1(printk(KERN_DEBUG "jffs2: MTD device #%u doesn't appear to exist\n", mtdnr)); return -EINVAL; } return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt); } static int jffs2_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct vfsmount *mnt) { int err; struct nameidata nd; int mtdnr; if (!dev_name) return -EINVAL; D1(printk(KERN_DEBUG "jffs2_get_sb(): dev_name \"%s\"\n", dev_name)); /* The preferred way of mounting in future; especially when CONFIG_BLK_DEV is implemented - we specify the underlying MTD device by number or by name, so that we don't require block device support to be present in the kernel. */ /* FIXME: How to do the root fs this way? */ if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') { /* Probably mounting without the blkdev crap */ if (dev_name[3] == ':') { struct mtd_info *mtd; /* Mount by MTD device name */ D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name+4)); for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) { mtd = get_mtd_device(NULL, mtdnr); if (mtd) { if (!strcmp(mtd->name, dev_name+4)) return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt); put_mtd_device(mtd); } } printk(KERN_NOTICE "jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name+4); } else if (isdigit(dev_name[3])) { /* Mount by MTD device number name */ char *endptr; mtdnr = simple_strtoul(dev_name+3, &endptr, 0); if (!*endptr) { /* It was a valid number */ D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr)); return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt); } } } /* Try the old way - the hack where we allowed users to mount /dev/mtdblock$(n) but didn't actually _use_ the blkdev */ err = path_lookup(dev_name, LOOKUP_FOLLOW, &nd); D1(printk(KERN_DEBUG "jffs2_get_sb(): path_lookup() returned %d, inode %p\n", err, nd.dentry->d_inode)); if (err) return err; err = -EINVAL; if (!S_ISBLK(nd.dentry->d_inode->i_mode)) goto out; if (nd.mnt->mnt_flags & MNT_NODEV) { err = -EACCES; goto out; } if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR) { if (!(flags & MS_SILENT)) printk(KERN_NOTICE "Attempt to mount non-MTD device \"%s\" as JFFS2\n", dev_name); goto out; } mtdnr = iminor(nd.dentry->d_inode); path_release(&nd); return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt); out: path_release(&nd); return err; } static void jffs2_put_super (struct super_block *sb) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n")); down(&c->alloc_sem); jffs2_flush_wbuf_pad(c); up(&c->alloc_sem); jffs2_sum_exit(c); jffs2_free_ino_caches(c); jffs2_free_raw_node_refs(c); if (jffs2_blocks_use_vmalloc(c)) vfree(c->blocks); else kfree(c->blocks); jffs2_flash_cleanup(c); kfree(c->inocache_list); jffs2_clear_xattr_subsystem(c); if (c->mtd->sync) c->mtd->sync(c->mtd); D1(printk(KERN_DEBUG "jffs2_put_super returning\n")); } static void jffs2_kill_sb(struct super_block *sb) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); if (!(sb->s_flags & MS_RDONLY)) jffs2_stop_garbage_collect_thread(c); generic_shutdown_super(sb); put_mtd_device(c->mtd); kfree(c); } static struct file_system_type jffs2_fs_type = { .owner = THIS_MODULE, .name = "jffs2", .get_sb = jffs2_get_sb, .kill_sb = jffs2_kill_sb, }; static int __init init_jffs2_fs(void) { int ret; /* Paranoia checks for on-medium structures. If we ask GCC to pack them with __attribute__((packed)) then it _also_ assumes that they're not aligned -- so it emits crappy code on some architectures. Ideally we want an attribute which means just 'no padding', without the alignment thing. But GCC doesn't have that -- we have to just hope the structs are the right sizes, instead. */ BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12); BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40); BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68); BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32); printk(KERN_INFO "JFFS2 version 2.2." #ifdef CONFIG_JFFS2_FS_WRITEBUFFER " (NAND)" #endif #ifdef CONFIG_JFFS2_SUMMARY " (SUMMARY) " #endif " (C) 2001-2006 Red Hat, Inc.\n"); jffs2_inode_cachep = kmem_cache_create("jffs2_i", sizeof(struct jffs2_inode_info), 0, (SLAB_RECLAIM_ACCOUNT| SLAB_MEM_SPREAD), jffs2_i_init_once, NULL); if (!jffs2_inode_cachep) { printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n"); return -ENOMEM; } ret = jffs2_compressors_init(); if (ret) { printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n"); goto out; } ret = jffs2_create_slab_caches(); if (ret) { printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n"); goto out_compressors; } ret = register_filesystem(&jffs2_fs_type); if (ret) { printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n"); goto out_slab; } return 0; out_slab: jffs2_destroy_slab_caches(); out_compressors: jffs2_compressors_exit(); out: kmem_cache_destroy(jffs2_inode_cachep); return ret; } static void __exit exit_jffs2_fs(void) { unregister_filesystem(&jffs2_fs_type); jffs2_destroy_slab_caches(); jffs2_compressors_exit(); kmem_cache_destroy(jffs2_inode_cachep); } module_init(init_jffs2_fs); module_exit(exit_jffs2_fs); MODULE_DESCRIPTION("The Journalling Flash File System, v2"); MODULE_AUTHOR("Red Hat, Inc."); MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for // the sake of this tag. It's Free Software.