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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/jffs2/super.c
Initial import
Diffstat (limited to 'fs/jffs2/super.c')
-rw-r--r--fs/jffs2/super.c442
1 files changed, 442 insertions, 0 deletions
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
new file mode 100644
index 000000000..d86c5e317
--- /dev/null
+++ b/fs/jffs2/super.c
@@ -0,0 +1,442 @@
+/*
+ * 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(d_inode(child)->i_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);
+ 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);
+ 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),
+ 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.