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441 lines
11 KiB
441 lines
11 KiB
/* |
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* JFFS2 -- Journalling Flash File System, Version 2. |
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* |
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* Copyright © 2001-2007 Red Hat, Inc. |
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* |
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* Created by David Woodhouse <[email protected]> |
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* |
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* For licensing information, see the file 'LICENCE' in this directory. |
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* |
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*/ |
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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#include <linux/kernel.h> |
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#include <linux/module.h> |
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#include <linux/slab.h> |
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#include <linux/init.h> |
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#include <linux/list.h> |
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#include <linux/fs.h> |
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#include <linux/err.h> |
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#include <linux/mount.h> |
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#include <linux/fs_context.h> |
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#include <linux/fs_parser.h> |
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#include <linux/jffs2.h> |
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#include <linux/pagemap.h> |
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#include <linux/mtd/super.h> |
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#include <linux/ctype.h> |
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#include <linux/namei.h> |
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#include <linux/seq_file.h> |
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#include <linux/exportfs.h> |
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#include "compr.h" |
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#include "nodelist.h" |
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static void jffs2_put_super(struct super_block *); |
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static struct kmem_cache *jffs2_inode_cachep; |
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static struct inode *jffs2_alloc_inode(struct super_block *sb) |
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{ |
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struct jffs2_inode_info *f; |
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f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL); |
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if (!f) |
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return NULL; |
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return &f->vfs_inode; |
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} |
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static void jffs2_free_inode(struct inode *inode) |
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{ |
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struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); |
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kfree(f->target); |
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kmem_cache_free(jffs2_inode_cachep, f); |
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} |
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static void jffs2_i_init_once(void *foo) |
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{ |
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struct jffs2_inode_info *f = foo; |
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mutex_init(&f->sem); |
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inode_init_once(&f->vfs_inode); |
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} |
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static const char *jffs2_compr_name(unsigned int compr) |
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{ |
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switch (compr) { |
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case JFFS2_COMPR_MODE_NONE: |
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return "none"; |
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#ifdef CONFIG_JFFS2_LZO |
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case JFFS2_COMPR_MODE_FORCELZO: |
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return "lzo"; |
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#endif |
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#ifdef CONFIG_JFFS2_ZLIB |
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case JFFS2_COMPR_MODE_FORCEZLIB: |
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return "zlib"; |
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#endif |
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default: |
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/* should never happen; programmer error */ |
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WARN_ON(1); |
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return ""; |
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} |
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} |
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static int jffs2_show_options(struct seq_file *s, struct dentry *root) |
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{ |
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struct jffs2_sb_info *c = JFFS2_SB_INFO(root->d_sb); |
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struct jffs2_mount_opts *opts = &c->mount_opts; |
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if (opts->override_compr) |
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seq_printf(s, ",compr=%s", jffs2_compr_name(opts->compr)); |
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if (opts->set_rp_size) |
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seq_printf(s, ",rp_size=%u", opts->rp_size / 1024); |
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return 0; |
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} |
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static int jffs2_sync_fs(struct super_block *sb, int wait) |
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{ |
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struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); |
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#ifdef CONFIG_JFFS2_FS_WRITEBUFFER |
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if (jffs2_is_writebuffered(c)) |
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cancel_delayed_work_sync(&c->wbuf_dwork); |
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#endif |
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mutex_lock(&c->alloc_sem); |
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jffs2_flush_wbuf_pad(c); |
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mutex_unlock(&c->alloc_sem); |
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return 0; |
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} |
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static struct inode *jffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, |
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uint32_t generation) |
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{ |
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/* We don't care about i_generation. We'll destroy the flash |
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before we start re-using inode numbers anyway. And even |
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if that wasn't true, we'd have other problems...*/ |
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return jffs2_iget(sb, ino); |
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} |
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static struct dentry *jffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, |
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int fh_len, int fh_type) |
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{ |
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return generic_fh_to_dentry(sb, fid, fh_len, fh_type, |
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jffs2_nfs_get_inode); |
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} |
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static struct dentry *jffs2_fh_to_parent(struct super_block *sb, struct fid *fid, |
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int fh_len, int fh_type) |
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{ |
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return generic_fh_to_parent(sb, fid, fh_len, fh_type, |
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jffs2_nfs_get_inode); |
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} |
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static struct dentry *jffs2_get_parent(struct dentry *child) |
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{ |
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struct jffs2_inode_info *f; |
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uint32_t pino; |
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BUG_ON(!d_is_dir(child)); |
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f = JFFS2_INODE_INFO(d_inode(child)); |
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pino = f->inocache->pino_nlink; |
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JFFS2_DEBUG("Parent of directory ino #%u is #%u\n", |
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f->inocache->ino, pino); |
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return d_obtain_alias(jffs2_iget(child->d_sb, pino)); |
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} |
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static const struct export_operations jffs2_export_ops = { |
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.get_parent = jffs2_get_parent, |
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.fh_to_dentry = jffs2_fh_to_dentry, |
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.fh_to_parent = jffs2_fh_to_parent, |
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}; |
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/* |
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* JFFS2 mount options. |
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* |
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* Opt_source: The source device |
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* Opt_override_compr: override default compressor |
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* Opt_rp_size: size of reserved pool in KiB |
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*/ |
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enum { |
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Opt_override_compr, |
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Opt_rp_size, |
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}; |
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static const struct constant_table jffs2_param_compr[] = { |
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{"none", JFFS2_COMPR_MODE_NONE }, |
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#ifdef CONFIG_JFFS2_LZO |
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{"lzo", JFFS2_COMPR_MODE_FORCELZO }, |
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#endif |
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#ifdef CONFIG_JFFS2_ZLIB |
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{"zlib", JFFS2_COMPR_MODE_FORCEZLIB }, |
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#endif |
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{} |
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}; |
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static const struct fs_parameter_spec jffs2_fs_parameters[] = { |
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fsparam_enum ("compr", Opt_override_compr, jffs2_param_compr), |
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fsparam_u32 ("rp_size", Opt_rp_size), |
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{} |
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}; |
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static int jffs2_parse_param(struct fs_context *fc, struct fs_parameter *param) |
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{ |
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struct fs_parse_result result; |
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struct jffs2_sb_info *c = fc->s_fs_info; |
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int opt; |
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opt = fs_parse(fc, jffs2_fs_parameters, param, &result); |
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if (opt < 0) |
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return opt; |
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switch (opt) { |
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case Opt_override_compr: |
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c->mount_opts.compr = result.uint_32; |
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c->mount_opts.override_compr = true; |
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break; |
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case Opt_rp_size: |
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if (result.uint_32 > UINT_MAX / 1024) |
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return invalf(fc, "jffs2: rp_size unrepresentable"); |
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c->mount_opts.rp_size = result.uint_32 * 1024; |
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c->mount_opts.set_rp_size = true; |
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break; |
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default: |
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return -EINVAL; |
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} |
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return 0; |
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} |
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static inline void jffs2_update_mount_opts(struct fs_context *fc) |
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{ |
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struct jffs2_sb_info *new_c = fc->s_fs_info; |
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struct jffs2_sb_info *c = JFFS2_SB_INFO(fc->root->d_sb); |
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mutex_lock(&c->alloc_sem); |
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if (new_c->mount_opts.override_compr) { |
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c->mount_opts.override_compr = new_c->mount_opts.override_compr; |
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c->mount_opts.compr = new_c->mount_opts.compr; |
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} |
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if (new_c->mount_opts.set_rp_size) { |
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c->mount_opts.set_rp_size = new_c->mount_opts.set_rp_size; |
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c->mount_opts.rp_size = new_c->mount_opts.rp_size; |
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} |
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mutex_unlock(&c->alloc_sem); |
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} |
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static int jffs2_reconfigure(struct fs_context *fc) |
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{ |
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struct super_block *sb = fc->root->d_sb; |
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sync_filesystem(sb); |
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jffs2_update_mount_opts(fc); |
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return jffs2_do_remount_fs(sb, fc); |
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} |
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static const struct super_operations jffs2_super_operations = |
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{ |
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.alloc_inode = jffs2_alloc_inode, |
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.free_inode = jffs2_free_inode, |
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.put_super = jffs2_put_super, |
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.statfs = jffs2_statfs, |
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.evict_inode = jffs2_evict_inode, |
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.dirty_inode = jffs2_dirty_inode, |
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.show_options = jffs2_show_options, |
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.sync_fs = jffs2_sync_fs, |
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}; |
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/* |
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* fill in the superblock |
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*/ |
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static int jffs2_fill_super(struct super_block *sb, struct fs_context *fc) |
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{ |
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struct jffs2_sb_info *c = sb->s_fs_info; |
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jffs2_dbg(1, "jffs2_get_sb_mtd():" |
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" New superblock for device %d (\"%s\")\n", |
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sb->s_mtd->index, sb->s_mtd->name); |
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c->mtd = sb->s_mtd; |
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c->os_priv = sb; |
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if (c->mount_opts.rp_size > c->mtd->size) |
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return invalf(fc, "jffs2: Too large reserve pool specified, max is %llu KB", |
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c->mtd->size / 1024); |
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/* Initialize JFFS2 superblock locks, the further initialization will |
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* be done later */ |
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mutex_init(&c->alloc_sem); |
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mutex_init(&c->erase_free_sem); |
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init_waitqueue_head(&c->erase_wait); |
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init_waitqueue_head(&c->inocache_wq); |
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spin_lock_init(&c->erase_completion_lock); |
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spin_lock_init(&c->inocache_lock); |
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sb->s_op = &jffs2_super_operations; |
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sb->s_export_op = &jffs2_export_ops; |
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sb->s_flags = sb->s_flags | SB_NOATIME; |
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sb->s_xattr = jffs2_xattr_handlers; |
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#ifdef CONFIG_JFFS2_FS_POSIX_ACL |
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sb->s_flags |= SB_POSIXACL; |
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#endif |
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return jffs2_do_fill_super(sb, fc); |
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} |
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static int jffs2_get_tree(struct fs_context *fc) |
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{ |
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return get_tree_mtd(fc, jffs2_fill_super); |
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} |
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static void jffs2_free_fc(struct fs_context *fc) |
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{ |
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kfree(fc->s_fs_info); |
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} |
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static const struct fs_context_operations jffs2_context_ops = { |
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.free = jffs2_free_fc, |
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.parse_param = jffs2_parse_param, |
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.get_tree = jffs2_get_tree, |
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.reconfigure = jffs2_reconfigure, |
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}; |
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static int jffs2_init_fs_context(struct fs_context *fc) |
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{ |
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struct jffs2_sb_info *ctx; |
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ctx = kzalloc(sizeof(struct jffs2_sb_info), GFP_KERNEL); |
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if (!ctx) |
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return -ENOMEM; |
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fc->s_fs_info = ctx; |
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fc->ops = &jffs2_context_ops; |
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return 0; |
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} |
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static void jffs2_put_super (struct super_block *sb) |
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{ |
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struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); |
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jffs2_dbg(2, "%s()\n", __func__); |
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mutex_lock(&c->alloc_sem); |
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jffs2_flush_wbuf_pad(c); |
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mutex_unlock(&c->alloc_sem); |
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jffs2_sum_exit(c); |
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jffs2_free_ino_caches(c); |
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jffs2_free_raw_node_refs(c); |
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kvfree(c->blocks); |
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jffs2_flash_cleanup(c); |
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kfree(c->inocache_list); |
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jffs2_clear_xattr_subsystem(c); |
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mtd_sync(c->mtd); |
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jffs2_dbg(1, "%s(): returning\n", __func__); |
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} |
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static void jffs2_kill_sb(struct super_block *sb) |
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{ |
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struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); |
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if (c && !sb_rdonly(sb)) |
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jffs2_stop_garbage_collect_thread(c); |
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kill_mtd_super(sb); |
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kfree(c); |
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} |
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static struct file_system_type jffs2_fs_type = { |
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.owner = THIS_MODULE, |
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.name = "jffs2", |
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.init_fs_context = jffs2_init_fs_context, |
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.parameters = jffs2_fs_parameters, |
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.kill_sb = jffs2_kill_sb, |
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}; |
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MODULE_ALIAS_FS("jffs2"); |
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static int __init init_jffs2_fs(void) |
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{ |
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int ret; |
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/* Paranoia checks for on-medium structures. If we ask GCC |
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to pack them with __attribute__((packed)) then it _also_ |
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assumes that they're not aligned -- so it emits crappy |
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code on some architectures. Ideally we want an attribute |
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which means just 'no padding', without the alignment |
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thing. But GCC doesn't have that -- we have to just |
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hope the structs are the right sizes, instead. */ |
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BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12); |
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BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40); |
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BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68); |
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BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32); |
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pr_info("version 2.2." |
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#ifdef CONFIG_JFFS2_FS_WRITEBUFFER |
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" (NAND)" |
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#endif |
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#ifdef CONFIG_JFFS2_SUMMARY |
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" (SUMMARY) " |
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#endif |
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" © 2001-2006 Red Hat, Inc.\n"); |
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jffs2_inode_cachep = kmem_cache_create("jffs2_i", |
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sizeof(struct jffs2_inode_info), |
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0, (SLAB_RECLAIM_ACCOUNT| |
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SLAB_MEM_SPREAD|SLAB_ACCOUNT), |
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jffs2_i_init_once); |
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if (!jffs2_inode_cachep) { |
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pr_err("error: Failed to initialise inode cache\n"); |
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return -ENOMEM; |
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} |
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ret = jffs2_compressors_init(); |
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if (ret) { |
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pr_err("error: Failed to initialise compressors\n"); |
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goto out; |
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} |
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ret = jffs2_create_slab_caches(); |
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if (ret) { |
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pr_err("error: Failed to initialise slab caches\n"); |
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goto out_compressors; |
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} |
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ret = register_filesystem(&jffs2_fs_type); |
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if (ret) { |
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pr_err("error: Failed to register filesystem\n"); |
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goto out_slab; |
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} |
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return 0; |
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out_slab: |
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jffs2_destroy_slab_caches(); |
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out_compressors: |
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jffs2_compressors_exit(); |
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out: |
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kmem_cache_destroy(jffs2_inode_cachep); |
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return ret; |
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} |
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static void __exit exit_jffs2_fs(void) |
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{ |
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unregister_filesystem(&jffs2_fs_type); |
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jffs2_destroy_slab_caches(); |
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jffs2_compressors_exit(); |
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/* |
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* Make sure all delayed rcu free inodes are flushed before we |
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* destroy cache. |
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*/ |
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rcu_barrier(); |
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kmem_cache_destroy(jffs2_inode_cachep); |
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} |
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module_init(init_jffs2_fs); |
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module_exit(exit_jffs2_fs); |
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MODULE_DESCRIPTION("The Journalling Flash File System, v2"); |
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MODULE_AUTHOR("Red Hat, Inc."); |
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MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for |
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// the sake of this tag. It's Free Software.
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