/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright © 2001-2007 Red Hat, Inc. * * Created by David Woodhouse <dwmw2@infradead.org> * * For licensing information, see the file 'LICENCE' in this directory. * */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #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/err.h> #include <linux/mount.h> #include <linux/parser.h> #include <linux/jffs2.h> #include <linux/pagemap.h> #include <linux/mtd/super.h> #include <linux/ctype.h> #include <linux/namei.h> #include <linux/seq_file.h> #include <linux/exportfs.h> #include "compr.h" #include "nodelist.h" static void jffs2_put_super(struct super_block *); static struct kmem_cache *jffs2_inode_cachep; static struct inode *jffs2_alloc_inode(struct super_block *sb) { struct jffs2_inode_info *f; f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL); if (!f) return NULL; return &f->vfs_inode; } static void jffs2_i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode)); } static void jffs2_destroy_inode(struct inode *inode) { call_rcu(&inode->i_rcu, jffs2_i_callback); } static void jffs2_i_init_once(void *foo) { struct jffs2_inode_info *f = foo; mutex_init(&f->sem); inode_init_once(&f->vfs_inode); } static const char *jffs2_compr_name(unsigned int compr) { switch (compr) { case JFFS2_COMPR_MODE_NONE: return "none"; #ifdef CONFIG_JFFS2_LZO case JFFS2_COMPR_MODE_FORCELZO: return "lzo"; #endif #ifdef CONFIG_JFFS2_ZLIB case JFFS2_COMPR_MODE_FORCEZLIB: return "zlib"; #endif default: /* should never happen; programmer error */ WARN_ON(1); return ""; } } static int jffs2_show_options(struct seq_file *s, struct dentry *root) { struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb); struct jffs2_mount_opts *opts = &c->mount_opts; if (opts->override_compr) seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr)); if (opts->rp_size) seq_printf(s, ",rp_size=%u", opts->rp_size / 1024); return 0; } static int jffs2_sync_fs(struct super_block *sb, int wait) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); #ifdef CONFIG_JFFS2_FS_WRITEBUFFER cancel_delayed_work_sync(&c->wbuf_dwork); #endif mutex_lock(&c->alloc_sem); jffs2_flush_wbuf_pad(c); mutex_unlock(&c->alloc_sem); return 0; } static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, uint32_t generation) { /* We don't care about i_generation. We'll destroy the flash before we start re-using inode numbers anyway. And even if that wasn't true, we'd have other problems...*/ return jffs2_iget(sb, ino); } static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { return generic_fh_to_dentry(sb, fid, fh_len, fh_type, jffs2_nfs_get_inode); } static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type) { return generic_fh_to_parent(sb, fid, fh_len, fh_type, jffs2_nfs_get_inode); } static struct dentry *jffs2_get_parent(struct dentry *child) { struct jffs2_inode_info *f; uint32_t pino; BUG_ON(!d_is_dir(child)); f = JFFS2_INODE_INFO(d_inode(child)); pino = f->inocache->pino_nlink; JFFS2_DEBUG("Parent of directory ino #%u is #%u\n", f->inocache->ino, pino); return d_obtain_alias(jffs2_iget(child->d_sb, pino)); } static const struct export_operations jffs2_export_ops = { .get_parent = jffs2_get_parent, .fh_to_dentry = jffs2_fh_to_dentry, .fh_to_parent = jffs2_fh_to_parent, }; /* * JFFS2 mount options. * * Opt_override_compr: override default compressor * Opt_rp_size: size of reserved pool in KiB * Opt_err: just end of array marker */ enum { Opt_override_compr, Opt_rp_size, Opt_err, }; static const match_table_t tokens = { {Opt_override_compr, "compr=%s"}, {Opt_rp_size, "rp_size=%u"}, {Opt_err, NULL}, }; static int jffs2_parse_options(struct jffs2_sb_info *c, char *data) { substring_t args[MAX_OPT_ARGS]; char *p, *name; unsigned int opt; if (!data) return 0; while ((p = strsep(&data, ","))) { int token; if (!*p) continue; token = match_token(p, tokens, args); switch (token) { case Opt_override_compr: name = match_strdup(&args[0]); if (!name) return -ENOMEM; if (!strcmp(name, "none")) c->mount_opts.compr = JFFS2_COMPR_MODE_NONE; #ifdef CONFIG_JFFS2_LZO else if (!strcmp(name, "lzo")) c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO; #endif #ifdef CONFIG_JFFS2_ZLIB else if (!strcmp(name, "zlib")) c->mount_opts.compr = JFFS2_COMPR_MODE_FORCEZLIB; #endif else { pr_err("Error: unknown compressor \"%s\"\n", name); kfree(name); return -EINVAL; } kfree(name); c->mount_opts.override_compr = true; break; case Opt_rp_size: if (match_int(&args[0], &opt)) return -EINVAL; opt *= 1024; if (opt > c->mtd->size) { pr_warn("Too large reserve pool specified, max " "is %llu KB\n", c->mtd->size / 1024); return -EINVAL; } c->mount_opts.rp_size = opt; break; default: pr_err("Error: unrecognized mount option '%s' or missing value\n", p); return -EINVAL; } } return 0; } static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); int err; sync_filesystem(sb); err = jffs2_parse_options(c, data); if (err) return -EINVAL; return jffs2_do_remount_fs(sb, flags, data); } static const struct super_operations jffs2_super_operations = { .alloc_inode = jffs2_alloc_inode, .destroy_inode =jffs2_destroy_inode, .put_super = jffs2_put_super, .statfs = jffs2_statfs, .remount_fs = jffs2_remount_fs, .evict_inode = jffs2_evict_inode, .dirty_inode = jffs2_dirty_inode, .show_options = jffs2_show_options, .sync_fs = jffs2_sync_fs, }; /* * fill in the superblock */ static int jffs2_fill_super(struct super_block *sb, void *data, int silent) { struct jffs2_sb_info *c; int ret; jffs2_dbg(1, "jffs2_get_sb_mtd():" " New superblock for device %d (\"%s\")\n", sb->s_mtd->index, sb->s_mtd->name); c = kzalloc(sizeof(*c), GFP_KERNEL); if (!c) return -ENOMEM; c->mtd = sb->s_mtd; c->os_priv = sb; sb->s_fs_info = c; ret = jffs2_parse_options(c, data); if (ret) { kfree(c); return -EINVAL; } /* Initialize JFFS2 superblock locks, the further initialization will * be done later */ mutex_init(&c->alloc_sem); mutex_init(&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_export_op = &jffs2_export_ops; sb->s_flags = sb->s_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, silent); return ret; } static struct dentry *jffs2_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { return mount_mtd(fs_type, flags, dev_name, data, jffs2_fill_super); } static void jffs2_put_super (struct super_block *sb) { struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); jffs2_dbg(2, "%s()\n", __func__); mutex_lock(&c->alloc_sem); jffs2_flush_wbuf_pad(c); mutex_unlock(&c->alloc_sem); jffs2_sum_exit(c); jffs2_free_ino_caches(c); jffs2_free_raw_node_refs(c); kvfree(c->blocks); jffs2_flash_cleanup(c); kfree(c->inocache_list); jffs2_clear_xattr_subsystem(c); mtd_sync(c->mtd); jffs2_dbg(1, "%s(): returning\n", __func__); } 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); kill_mtd_super(sb); kfree(c); } static struct file_system_type jffs2_fs_type = { .owner = THIS_MODULE, .name = "jffs2", .mount = jffs2_mount, .kill_sb = jffs2_kill_sb, }; MODULE_ALIAS_FS("jffs2"); 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); pr_info("version 2.2." #ifdef CONFIG_JFFS2_FS_WRITEBUFFER " (NAND)" #endif #ifdef CONFIG_JFFS2_SUMMARY " (SUMMARY) " #endif " © 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|SLAB_ACCOUNT), jffs2_i_init_once); if (!jffs2_inode_cachep) { pr_err("error: Failed to initialise inode cache\n"); return -ENOMEM; } ret = jffs2_compressors_init(); if (ret) { pr_err("error: Failed to initialise compressors\n"); goto out; } ret = jffs2_create_slab_caches(); if (ret) { pr_err("error: Failed to initialise slab caches\n"); goto out_compressors; } ret = register_filesystem(&jffs2_fs_type); if (ret) { pr_err("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(); /* * Make sure all delayed rcu free inodes are flushed before we * destroy cache. */ rcu_barrier(); 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.