Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 878 insertions, 0 deletions

diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
new file mode 100644
index 000000000..c0aabbcbf
--- /dev/null
+++ b/fs/jffs2/dir.c
@@ -0,0 +1,878 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright © 2001-2007 Red Hat, Inc.
+ * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
+ *
+ * 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/slab.h>
+#include <linux/fs.h>
+#include <linux/crc32.h>
+#include <linux/jffs2.h>
+#include "jffs2_fs_i.h"
+#include "jffs2_fs_sb.h"
+#include <linux/time.h>
+#include "nodelist.h"
+
+static int jffs2_readdir (struct file *, struct dir_context *);
+
+static int jffs2_create (struct user_namespace *, struct inode *,
+		         struct dentry *, umode_t, bool);
+static struct dentry *jffs2_lookup (struct inode *,struct dentry *,
+				    unsigned int);
+static int jffs2_link (struct dentry *,struct inode *,struct dentry *);
+static int jffs2_unlink (struct inode *,struct dentry *);
+static int jffs2_symlink (struct user_namespace *, struct inode *,
+			  struct dentry *, const char *);
+static int jffs2_mkdir (struct user_namespace *, struct inode *,struct dentry *,
+			umode_t);
+static int jffs2_rmdir (struct inode *,struct dentry *);
+static int jffs2_mknod (struct user_namespace *, struct inode *,struct dentry *,
+			umode_t,dev_t);
+static int jffs2_rename (struct user_namespace *, struct inode *,
+			 struct dentry *, struct inode *, struct dentry *,
+			 unsigned int);
+
+const struct file_operations jffs2_dir_operations =
+{
+	.read =		generic_read_dir,
+	.iterate_shared=jffs2_readdir,
+	.unlocked_ioctl=jffs2_ioctl,
+	.fsync =	jffs2_fsync,
+	.llseek =	generic_file_llseek,
+};
+
+
+const struct inode_operations jffs2_dir_inode_operations =
+{
+	.create =	jffs2_create,
+	.lookup =	jffs2_lookup,
+	.link =		jffs2_link,
+	.unlink =	jffs2_unlink,
+	.symlink =	jffs2_symlink,
+	.mkdir =	jffs2_mkdir,
+	.rmdir =	jffs2_rmdir,
+	.mknod =	jffs2_mknod,
+	.rename =	jffs2_rename,
+	.get_acl =	jffs2_get_acl,
+	.set_acl =	jffs2_set_acl,
+	.setattr =	jffs2_setattr,
+	.listxattr =	jffs2_listxattr,
+};
+
+/***********************************************************************/
+
+
+/* We keep the dirent list sorted in increasing order of name hash,
+   and we use the same hash function as the dentries. Makes this
+   nice and simple
+*/
+static struct dentry *jffs2_lookup(struct inode *dir_i, struct dentry *target,
+				   unsigned int flags)
+{
+	struct jffs2_inode_info *dir_f;
+	struct jffs2_full_dirent *fd = NULL, *fd_list;
+	uint32_t ino = 0;
+	struct inode *inode = NULL;
+	unsigned int nhash;
+
+	jffs2_dbg(1, "jffs2_lookup()\n");
+
+	if (target->d_name.len > JFFS2_MAX_NAME_LEN)
+		return ERR_PTR(-ENAMETOOLONG);
+
+	dir_f = JFFS2_INODE_INFO(dir_i);
+
+	/* The 'nhash' on the fd_list is not the same as the dentry hash */
+	nhash = full_name_hash(NULL, target->d_name.name, target->d_name.len);
+
+	mutex_lock(&dir_f->sem);
+
+	/* NB: The 2.2 backport will need to explicitly check for '.' and '..' here */
+	for (fd_list = dir_f->dents; fd_list && fd_list->nhash <= nhash; fd_list = fd_list->next) {
+		if (fd_list->nhash == nhash &&
+		    (!fd || fd_list->version > fd->version) &&
+		    strlen(fd_list->name) == target->d_name.len &&
+		    !strncmp(fd_list->name, target->d_name.name, target->d_name.len)) {
+			fd = fd_list;
+		}
+	}
+	if (fd)
+		ino = fd->ino;
+	mutex_unlock(&dir_f->sem);
+	if (ino) {
+		inode = jffs2_iget(dir_i->i_sb, ino);
+		if (IS_ERR(inode))
+			pr_warn("iget() failed for ino #%u\n", ino);
+	}
+
+	return d_splice_alias(inode, target);
+}
+
+/***********************************************************************/
+
+
+static int jffs2_readdir(struct file *file, struct dir_context *ctx)
+{
+	struct inode *inode = file_inode(file);
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_full_dirent *fd;
+	unsigned long curofs = 1;
+
+	jffs2_dbg(1, "jffs2_readdir() for dir_i #%lu\n", inode->i_ino);
+
+	if (!dir_emit_dots(file, ctx))
+		return 0;
+
+	mutex_lock(&f->sem);
+	for (fd = f->dents; fd; fd = fd->next) {
+		curofs++;
+		/* First loop: curofs = 2; pos = 2 */
+		if (curofs < ctx->pos) {
+			jffs2_dbg(2, "Skipping dirent: \"%s\", ino #%u, type %d, because curofs %ld < offset %ld\n",
+				  fd->name, fd->ino, fd->type, curofs, (unsigned long)ctx->pos);
+			continue;
+		}
+		if (!fd->ino) {
+			jffs2_dbg(2, "Skipping deletion dirent \"%s\"\n",
+				  fd->name);
+			ctx->pos++;
+			continue;
+		}
+		jffs2_dbg(2, "Dirent %ld: \"%s\", ino #%u, type %d\n",
+			  (unsigned long)ctx->pos, fd->name, fd->ino, fd->type);
+		if (!dir_emit(ctx, fd->name, strlen(fd->name), fd->ino, fd->type))
+			break;
+		ctx->pos++;
+	}
+	mutex_unlock(&f->sem);
+	return 0;
+}
+
+/***********************************************************************/
+
+
+static int jffs2_create(struct user_namespace *mnt_userns, struct inode *dir_i,
+			struct dentry *dentry, umode_t mode, bool excl)
+{
+	struct jffs2_raw_inode *ri;
+	struct jffs2_inode_info *f, *dir_f;
+	struct jffs2_sb_info *c;
+	struct inode *inode;
+	int ret;
+
+	ri = jffs2_alloc_raw_inode();
+	if (!ri)
+		return -ENOMEM;
+
+	c = JFFS2_SB_INFO(dir_i->i_sb);
+
+	jffs2_dbg(1, "%s()\n", __func__);
+
+	inode = jffs2_new_inode(dir_i, mode, ri);
+
+	if (IS_ERR(inode)) {
+		jffs2_dbg(1, "jffs2_new_inode() failed\n");
+		jffs2_free_raw_inode(ri);
+		return PTR_ERR(inode);
+	}
+
+	inode->i_op = &jffs2_file_inode_operations;
+	inode->i_fop = &jffs2_file_operations;
+	inode->i_mapping->a_ops = &jffs2_file_address_operations;
+	inode->i_mapping->nrpages = 0;
+
+	f = JFFS2_INODE_INFO(inode);
+	dir_f = JFFS2_INODE_INFO(dir_i);
+
+	/* jffs2_do_create() will want to lock it, _after_ reserving
+	   space and taking c-alloc_sem. If we keep it locked here,
+	   lockdep gets unhappy (although it's a false positive;
+	   nothing else will be looking at this inode yet so there's
+	   no chance of AB-BA deadlock involving its f->sem). */
+	mutex_unlock(&f->sem);
+
+	ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name);
+	if (ret)
+		goto fail;
+
+	dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
+
+	jffs2_free_raw_inode(ri);
+
+	jffs2_dbg(1, "%s(): Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
+		  __func__, inode->i_ino, inode->i_mode, inode->i_nlink,
+		  f->inocache->pino_nlink, inode->i_mapping->nrpages);
+
+	d_instantiate_new(dentry, inode);
+	return 0;
+
+ fail:
+	iget_failed(inode);
+	jffs2_free_raw_inode(ri);
+	return ret;
+}
+
+/***********************************************************************/
+
+
+static int jffs2_unlink(struct inode *dir_i, struct dentry *dentry)
+{
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
+	struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
+	struct jffs2_inode_info *dead_f = JFFS2_INODE_INFO(d_inode(dentry));
+	int ret;
+	uint32_t now = JFFS2_NOW();
+
+	ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
+			      dentry->d_name.len, dead_f, now);
+	if (dead_f->inocache)
+		set_nlink(d_inode(dentry), dead_f->inocache->pino_nlink);
+	if (!ret)
+		dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
+	return ret;
+}
+/***********************************************************************/
+
+
+static int jffs2_link (struct dentry *old_dentry, struct inode *dir_i, struct dentry *dentry)
+{
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dentry->d_sb);
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
+	struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
+	int ret;
+	uint8_t type;
+	uint32_t now;
+
+	/* Don't let people make hard links to bad inodes. */
+	if (!f->inocache)
+		return -EIO;
+
+	if (d_is_dir(old_dentry))
+		return -EPERM;
+
+	/* XXX: This is ugly */
+	type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12;
+	if (!type) type = DT_REG;
+
+	now = JFFS2_NOW();
+	ret = jffs2_do_link(c, dir_f, f->inocache->ino, type, dentry->d_name.name, dentry->d_name.len, now);
+
+	if (!ret) {
+		mutex_lock(&f->sem);
+		set_nlink(d_inode(old_dentry), ++f->inocache->pino_nlink);
+		mutex_unlock(&f->sem);
+		d_instantiate(dentry, d_inode(old_dentry));
+		dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
+		ihold(d_inode(old_dentry));
+	}
+	return ret;
+}
+
+/***********************************************************************/
+
+static int jffs2_symlink (struct user_namespace *mnt_userns, struct inode *dir_i,
+			  struct dentry *dentry, const char *target)
+{
+	struct jffs2_inode_info *f, *dir_f;
+	struct jffs2_sb_info *c;
+	struct inode *inode;
+	struct jffs2_raw_inode *ri;
+	struct jffs2_raw_dirent *rd;
+	struct jffs2_full_dnode *fn;
+	struct jffs2_full_dirent *fd;
+	int namelen;
+	uint32_t alloclen;
+	int ret, targetlen = strlen(target);
+
+	/* FIXME: If you care. We'd need to use frags for the target
+	   if it grows much more than this */
+	if (targetlen > 254)
+		return -ENAMETOOLONG;
+
+	ri = jffs2_alloc_raw_inode();
+
+	if (!ri)
+		return -ENOMEM;
+
+	c = JFFS2_SB_INFO(dir_i->i_sb);
+
+	/* Try to reserve enough space for both node and dirent.
+	 * Just the node will do for now, though
+	 */
+	namelen = dentry->d_name.len;
+	ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
+				  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
+
+	if (ret) {
+		jffs2_free_raw_inode(ri);
+		return ret;
+	}
+
+	inode = jffs2_new_inode(dir_i, S_IFLNK | S_IRWXUGO, ri);
+
+	if (IS_ERR(inode)) {
+		jffs2_free_raw_inode(ri);
+		jffs2_complete_reservation(c);
+		return PTR_ERR(inode);
+	}
+
+	inode->i_op = &jffs2_symlink_inode_operations;
+
+	f = JFFS2_INODE_INFO(inode);
+
+	inode->i_size = targetlen;
+	ri->isize = ri->dsize = ri->csize = cpu_to_je32(inode->i_size);
+	ri->totlen = cpu_to_je32(sizeof(*ri) + inode->i_size);
+	ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
+
+	ri->compr = JFFS2_COMPR_NONE;
+	ri->data_crc = cpu_to_je32(crc32(0, target, targetlen));
+	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
+
+	fn = jffs2_write_dnode(c, f, ri, target, targetlen, ALLOC_NORMAL);
+
+	jffs2_free_raw_inode(ri);
+
+	if (IS_ERR(fn)) {
+		/* Eeek. Wave bye bye */
+		mutex_unlock(&f->sem);
+		jffs2_complete_reservation(c);
+		ret = PTR_ERR(fn);
+		goto fail;
+	}
+
+	/* We use f->target field to store the target path. */
+	f->target = kmemdup(target, targetlen + 1, GFP_KERNEL);
+	if (!f->target) {
+		pr_warn("Can't allocate %d bytes of memory\n", targetlen + 1);
+		mutex_unlock(&f->sem);
+		jffs2_complete_reservation(c);
+		ret = -ENOMEM;
+		goto fail;
+	}
+	inode->i_link = f->target;
+
+	jffs2_dbg(1, "%s(): symlink's target '%s' cached\n",
+		  __func__, (char *)f->target);
+
+	/* No data here. Only a metadata node, which will be
+	   obsoleted by the first data write
+	*/
+	f->metadata = fn;
+	mutex_unlock(&f->sem);
+
+	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_init_acl_post(inode);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
+				  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
+	if (ret)
+		goto fail;
+
+	rd = jffs2_alloc_raw_dirent();
+	if (!rd) {
+		/* Argh. Now we treat it like a normal delete */
+		jffs2_complete_reservation(c);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	dir_f = JFFS2_INODE_INFO(dir_i);
+	mutex_lock(&dir_f->sem);
+
+	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
+	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
+	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
+
+	rd->pino = cpu_to_je32(dir_i->i_ino);
+	rd->version = cpu_to_je32(++dir_f->highest_version);
+	rd->ino = cpu_to_je32(inode->i_ino);
+	rd->mctime = cpu_to_je32(JFFS2_NOW());
+	rd->nsize = namelen;
+	rd->type = DT_LNK;
+	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
+	rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
+
+	fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
+
+	if (IS_ERR(fd)) {
+		/* dirent failed to write. Delete the inode normally
+		   as if it were the final unlink() */
+		jffs2_complete_reservation(c);
+		jffs2_free_raw_dirent(rd);
+		mutex_unlock(&dir_f->sem);
+		ret = PTR_ERR(fd);
+		goto fail;
+	}
+
+	dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
+
+	jffs2_free_raw_dirent(rd);
+
+	/* Link the fd into the inode's list, obsoleting an old
+	   one if necessary. */
+	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
+
+	mutex_unlock(&dir_f->sem);
+	jffs2_complete_reservation(c);
+
+	d_instantiate_new(dentry, inode);
+	return 0;
+
+ fail:
+	iget_failed(inode);
+	return ret;
+}
+
+
+static int jffs2_mkdir (struct user_namespace *mnt_userns, struct inode *dir_i,
+		        struct dentry *dentry, umode_t mode)
+{
+	struct jffs2_inode_info *f, *dir_f;
+	struct jffs2_sb_info *c;
+	struct inode *inode;
+	struct jffs2_raw_inode *ri;
+	struct jffs2_raw_dirent *rd;
+	struct jffs2_full_dnode *fn;
+	struct jffs2_full_dirent *fd;
+	int namelen;
+	uint32_t alloclen;
+	int ret;
+
+	mode |= S_IFDIR;
+
+	ri = jffs2_alloc_raw_inode();
+	if (!ri)
+		return -ENOMEM;
+
+	c = JFFS2_SB_INFO(dir_i->i_sb);
+
+	/* Try to reserve enough space for both node and dirent.
+	 * Just the node will do for now, though
+	 */
+	namelen = dentry->d_name.len;
+	ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
+				  JFFS2_SUMMARY_INODE_SIZE);
+
+	if (ret) {
+		jffs2_free_raw_inode(ri);
+		return ret;
+	}
+
+	inode = jffs2_new_inode(dir_i, mode, ri);
+
+	if (IS_ERR(inode)) {
+		jffs2_free_raw_inode(ri);
+		jffs2_complete_reservation(c);
+		return PTR_ERR(inode);
+	}
+
+	inode->i_op = &jffs2_dir_inode_operations;
+	inode->i_fop = &jffs2_dir_operations;
+
+	f = JFFS2_INODE_INFO(inode);
+
+	/* Directories get nlink 2 at start */
+	set_nlink(inode, 2);
+	/* but ic->pino_nlink is the parent ino# */
+	f->inocache->pino_nlink = dir_i->i_ino;
+
+	ri->data_crc = cpu_to_je32(0);
+	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
+
+	fn = jffs2_write_dnode(c, f, ri, NULL, 0, ALLOC_NORMAL);
+
+	jffs2_free_raw_inode(ri);
+
+	if (IS_ERR(fn)) {
+		/* Eeek. Wave bye bye */
+		mutex_unlock(&f->sem);
+		jffs2_complete_reservation(c);
+		ret = PTR_ERR(fn);
+		goto fail;
+	}
+	/* No data here. Only a metadata node, which will be
+	   obsoleted by the first data write
+	*/
+	f->metadata = fn;
+	mutex_unlock(&f->sem);
+
+	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_init_acl_post(inode);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
+				  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
+	if (ret)
+		goto fail;
+
+	rd = jffs2_alloc_raw_dirent();
+	if (!rd) {
+		/* Argh. Now we treat it like a normal delete */
+		jffs2_complete_reservation(c);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	dir_f = JFFS2_INODE_INFO(dir_i);
+	mutex_lock(&dir_f->sem);
+
+	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
+	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
+	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
+
+	rd->pino = cpu_to_je32(dir_i->i_ino);
+	rd->version = cpu_to_je32(++dir_f->highest_version);
+	rd->ino = cpu_to_je32(inode->i_ino);
+	rd->mctime = cpu_to_je32(JFFS2_NOW());
+	rd->nsize = namelen;
+	rd->type = DT_DIR;
+	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
+	rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
+
+	fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
+
+	if (IS_ERR(fd)) {
+		/* dirent failed to write. Delete the inode normally
+		   as if it were the final unlink() */
+		jffs2_complete_reservation(c);
+		jffs2_free_raw_dirent(rd);
+		mutex_unlock(&dir_f->sem);
+		ret = PTR_ERR(fd);
+		goto fail;
+	}
+
+	dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
+	inc_nlink(dir_i);
+
+	jffs2_free_raw_dirent(rd);
+
+	/* Link the fd into the inode's list, obsoleting an old
+	   one if necessary. */
+	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
+
+	mutex_unlock(&dir_f->sem);
+	jffs2_complete_reservation(c);
+
+	d_instantiate_new(dentry, inode);
+	return 0;
+
+ fail:
+	iget_failed(inode);
+	return ret;
+}
+
+static int jffs2_rmdir (struct inode *dir_i, struct dentry *dentry)
+{
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(dir_i->i_sb);
+	struct jffs2_inode_info *dir_f = JFFS2_INODE_INFO(dir_i);
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(dentry));
+	struct jffs2_full_dirent *fd;
+	int ret;
+	uint32_t now = JFFS2_NOW();
+
+	mutex_lock(&f->sem);
+	for (fd = f->dents ; fd; fd = fd->next) {
+		if (fd->ino) {
+			mutex_unlock(&f->sem);
+			return -ENOTEMPTY;
+		}
+	}
+	mutex_unlock(&f->sem);
+
+	ret = jffs2_do_unlink(c, dir_f, dentry->d_name.name,
+			      dentry->d_name.len, f, now);
+	if (!ret) {
+		dir_i->i_mtime = dir_i->i_ctime = ITIME(now);
+		clear_nlink(d_inode(dentry));
+		drop_nlink(dir_i);
+	}
+	return ret;
+}
+
+static int jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i,
+		        struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+	struct jffs2_inode_info *f, *dir_f;
+	struct jffs2_sb_info *c;
+	struct inode *inode;
+	struct jffs2_raw_inode *ri;
+	struct jffs2_raw_dirent *rd;
+	struct jffs2_full_dnode *fn;
+	struct jffs2_full_dirent *fd;
+	int namelen;
+	union jffs2_device_node dev;
+	int devlen = 0;
+	uint32_t alloclen;
+	int ret;
+
+	ri = jffs2_alloc_raw_inode();
+	if (!ri)
+		return -ENOMEM;
+
+	c = JFFS2_SB_INFO(dir_i->i_sb);
+
+	if (S_ISBLK(mode) || S_ISCHR(mode))
+		devlen = jffs2_encode_dev(&dev, rdev);
+
+	/* Try to reserve enough space for both node and dirent.
+	 * Just the node will do for now, though
+	 */
+	namelen = dentry->d_name.len;
+	ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
+				  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
+
+	if (ret) {
+		jffs2_free_raw_inode(ri);
+		return ret;
+	}
+
+	inode = jffs2_new_inode(dir_i, mode, ri);
+
+	if (IS_ERR(inode)) {
+		jffs2_free_raw_inode(ri);
+		jffs2_complete_reservation(c);
+		return PTR_ERR(inode);
+	}
+	inode->i_op = &jffs2_file_inode_operations;
+	init_special_inode(inode, inode->i_mode, rdev);
+
+	f = JFFS2_INODE_INFO(inode);
+
+	ri->dsize = ri->csize = cpu_to_je32(devlen);
+	ri->totlen = cpu_to_je32(sizeof(*ri) + devlen);
+	ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
+
+	ri->compr = JFFS2_COMPR_NONE;
+	ri->data_crc = cpu_to_je32(crc32(0, &dev, devlen));
+	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
+
+	fn = jffs2_write_dnode(c, f, ri, (char *)&dev, devlen, ALLOC_NORMAL);
+
+	jffs2_free_raw_inode(ri);
+
+	if (IS_ERR(fn)) {
+		/* Eeek. Wave bye bye */
+		mutex_unlock(&f->sem);
+		jffs2_complete_reservation(c);
+		ret = PTR_ERR(fn);
+		goto fail;
+	}
+	/* No data here. Only a metadata node, which will be
+	   obsoleted by the first data write
+	*/
+	f->metadata = fn;
+	mutex_unlock(&f->sem);
+
+	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i, &dentry->d_name);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_init_acl_post(inode);
+	if (ret)
+		goto fail;
+
+	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &alloclen,
+				  ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
+	if (ret)
+		goto fail;
+
+	rd = jffs2_alloc_raw_dirent();
+	if (!rd) {
+		/* Argh. Now we treat it like a normal delete */
+		jffs2_complete_reservation(c);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	dir_f = JFFS2_INODE_INFO(dir_i);
+	mutex_lock(&dir_f->sem);
+
+	rd->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	rd->nodetype = cpu_to_je16(JFFS2_NODETYPE_DIRENT);
+	rd->totlen = cpu_to_je32(sizeof(*rd) + namelen);
+	rd->hdr_crc = cpu_to_je32(crc32(0, rd, sizeof(struct jffs2_unknown_node)-4));
+
+	rd->pino = cpu_to_je32(dir_i->i_ino);
+	rd->version = cpu_to_je32(++dir_f->highest_version);
+	rd->ino = cpu_to_je32(inode->i_ino);
+	rd->mctime = cpu_to_je32(JFFS2_NOW());
+	rd->nsize = namelen;
+
+	/* XXX: This is ugly. */
+	rd->type = (mode & S_IFMT) >> 12;
+
+	rd->node_crc = cpu_to_je32(crc32(0, rd, sizeof(*rd)-8));
+	rd->name_crc = cpu_to_je32(crc32(0, dentry->d_name.name, namelen));
+
+	fd = jffs2_write_dirent(c, dir_f, rd, dentry->d_name.name, namelen, ALLOC_NORMAL);
+
+	if (IS_ERR(fd)) {
+		/* dirent failed to write. Delete the inode normally
+		   as if it were the final unlink() */
+		jffs2_complete_reservation(c);
+		jffs2_free_raw_dirent(rd);
+		mutex_unlock(&dir_f->sem);
+		ret = PTR_ERR(fd);
+		goto fail;
+	}
+
+	dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(rd->mctime));
+
+	jffs2_free_raw_dirent(rd);
+
+	/* Link the fd into the inode's list, obsoleting an old
+	   one if necessary. */
+	jffs2_add_fd_to_list(c, fd, &dir_f->dents);
+
+	mutex_unlock(&dir_f->sem);
+	jffs2_complete_reservation(c);
+
+	d_instantiate_new(dentry, inode);
+	return 0;
+
+ fail:
+	iget_failed(inode);
+	return ret;
+}
+
+static int jffs2_rename (struct user_namespace *mnt_userns,
+			 struct inode *old_dir_i, struct dentry *old_dentry,
+			 struct inode *new_dir_i, struct dentry *new_dentry,
+			 unsigned int flags)
+{
+	int ret;
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb);
+	struct jffs2_inode_info *victim_f = NULL;
+	uint8_t type;
+	uint32_t now;
+
+	if (flags & ~RENAME_NOREPLACE)
+		return -EINVAL;
+
+	/* The VFS will check for us and prevent trying to rename a
+	 * file over a directory and vice versa, but if it's a directory,
+	 * the VFS can't check whether the victim is empty. The filesystem
+	 * needs to do that for itself.
+	 */
+	if (d_really_is_positive(new_dentry)) {
+		victim_f = JFFS2_INODE_INFO(d_inode(new_dentry));
+		if (d_is_dir(new_dentry)) {
+			struct jffs2_full_dirent *fd;
+
+			mutex_lock(&victim_f->sem);
+			for (fd = victim_f->dents; fd; fd = fd->next) {
+				if (fd->ino) {
+					mutex_unlock(&victim_f->sem);
+					return -ENOTEMPTY;
+				}
+			}
+			mutex_unlock(&victim_f->sem);
+		}
+	}
+
+	/* XXX: We probably ought to alloc enough space for
+	   both nodes at the same time. Writing the new link,
+	   then getting -ENOSPC, is quite bad :)
+	*/
+
+	/* Make a hard link */
+
+	/* XXX: This is ugly */
+	type = (d_inode(old_dentry)->i_mode & S_IFMT) >> 12;
+	if (!type) type = DT_REG;
+
+	now = JFFS2_NOW();
+	ret = jffs2_do_link(c, JFFS2_INODE_INFO(new_dir_i),
+			    d_inode(old_dentry)->i_ino, type,
+			    new_dentry->d_name.name, new_dentry->d_name.len, now);
+
+	if (ret)
+		return ret;
+
+	if (victim_f) {
+		/* There was a victim. Kill it off nicely */
+		if (d_is_dir(new_dentry))
+			clear_nlink(d_inode(new_dentry));
+		else
+			drop_nlink(d_inode(new_dentry));
+		/* Don't oops if the victim was a dirent pointing to an
+		   inode which didn't exist. */
+		if (victim_f->inocache) {
+			mutex_lock(&victim_f->sem);
+			if (d_is_dir(new_dentry))
+				victim_f->inocache->pino_nlink = 0;
+			else
+				victim_f->inocache->pino_nlink--;
+			mutex_unlock(&victim_f->sem);
+		}
+	}
+
+	/* If it was a directory we moved, and there was no victim,
+	   increase i_nlink on its new parent */
+	if (d_is_dir(old_dentry) && !victim_f)
+		inc_nlink(new_dir_i);
+
+	/* Unlink the original */
+	ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
+			      old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
+
+	/* We don't touch inode->i_nlink */
+
+	if (ret) {
+		/* Oh shit. We really ought to make a single node which can do both atomically */
+		struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode(old_dentry));
+		mutex_lock(&f->sem);
+		inc_nlink(d_inode(old_dentry));
+		if (f->inocache && !d_is_dir(old_dentry))
+			f->inocache->pino_nlink++;
+		mutex_unlock(&f->sem);
+
+		pr_notice("%s(): Link succeeded, unlink failed (err %d). You now have a hard link\n",
+			  __func__, ret);
+		/*
+		 * We can't keep the target in dcache after that.
+		 * For one thing, we can't afford dentry aliases for directories.
+		 * For another, if there was a victim, we _can't_ set new inode
+		 * for that sucker and we have to trigger mount eviction - the
+		 * caller won't do it on its own since we are returning an error.
+		 */
+		d_invalidate(new_dentry);
+		new_dir_i->i_mtime = new_dir_i->i_ctime = ITIME(now);
+		return ret;
+	}
+
+	if (d_is_dir(old_dentry))
+		drop_nlink(old_dir_i);
+
+	new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now);
+
+	return 0;
+}
+