Merge git://git.infradead.org/jffs2-xattr-2.6

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

fs/Kconfig

@@ -1075,6 +1075,44 @@ config JFFS2_FS_DEBUG
 	  If reporting bugs, please try to have available a full dump of the
 	  messages at debug level 1 while the misbehaviour was occurring.
 
+config JFFS2_FS_XATTR
+	bool "JFFS2 XATTR support"
+	depends on JFFS2_FS
+	default n
+	help
+	  Extended attributes are name:value pairs associated with inodes by
+	  the kernel or by users (see the attr(5) manual page, or visit
+	  <http://acl.bestbits.at/> for details).
+	  
+	  If unsure, say N.
+
+config JFFS2_FS_POSIX_ACL
+	bool "JFFS2 POSIX Access Control Lists"
+	depends on JFFS2_FS_XATTR
+	default y
+	select FS_POSIX_ACL
+	help
+	  Posix Access Control Lists (ACLs) support permissions for users and
+	  groups beyond the owner/group/world scheme.
+	  
+	  To learn more about Access Control Lists, visit the Posix ACLs for
+	  Linux website <http://acl.bestbits.at/>.
+	  
+	  If you don't know what Access Control Lists are, say N
+
+config JFFS2_FS_SECURITY
+	bool "JFFS2 Security Labels"
+	depends on JFFS2_FS_XATTR
+	default y
+	help
+	  Security labels support alternative access control models
+	  implemented by security modules like SELinux.  This option
+	  enables an extended attribute handler for file security
+	  labels in the jffs2 filesystem.
+	  
+	  If you are not using a security module that requires using
+	  extended attributes for file security labels, say N.
+
 config JFFS2_FS_WRITEBUFFER
 	bool "JFFS2 write-buffering support"
 	depends on JFFS2_FS

fs/jffs2/Makefile

@@ -12,6 +12,9 @@ jffs2-y	+= symlink.o build.o erase.o background.o fs.o writev.o
 jffs2-y	+= super.o debug.o
 
 jffs2-$(CONFIG_JFFS2_FS_WRITEBUFFER)	+= wbuf.o
+jffs2-$(CONFIG_JFFS2_FS_XATTR)		+= xattr.o xattr_trusted.o xattr_user.o
+jffs2-$(CONFIG_JFFS2_FS_SECURITY)	+= security.o
+jffs2-$(CONFIG_JFFS2_FS_POSIX_ACL)	+= acl.o
 jffs2-$(CONFIG_JFFS2_RUBIN)	+= compr_rubin.o
 jffs2-$(CONFIG_JFFS2_RTIME)	+= compr_rtime.o
 jffs2-$(CONFIG_JFFS2_ZLIB)	+= compr_zlib.o

fs/jffs2/README.Locking

@@ -150,3 +150,24 @@ the buffer.
 
 Ordering constraints:
 	Lock wbuf_sem last, after the alloc_sem or and f->sem.
+
+
+	c->xattr_sem
+	------------
+
+This read/write semaphore protects against concurrent access to the
+xattr related objects which include stuff in superblock and ic->xref.
+In read-only path, write-semaphore is too much exclusion. It's enough
+by read-semaphore. But you must hold write-semaphore when updating,
+creating or deleting any xattr related object.
+
+Once xattr_sem released, there would be no assurance for the existence
+of those objects. Thus, a series of processes is often required to retry,
+when updating such a object is necessary under holding read semaphore.
+For example, do_jffs2_getxattr() holds read-semaphore to scan xref and
+xdatum at first. But it retries this process with holding write-semaphore
+after release read-semaphore, if it's necessary to load name/value pair
+from medium.
+
+Ordering constraints:
+	Lock xattr_sem last, after the alloc_sem.

fs/jffs2/acl.c

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/crc32.h>
+#include <linux/jffs2.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/mtd/mtd.h>
+#include "nodelist.h"
+
+static size_t jffs2_acl_size(int count)
+{
+	if (count <= 4) {
+		return sizeof(struct jffs2_acl_header)
+		       + count * sizeof(struct jffs2_acl_entry_short);
+	} else {
+		return sizeof(struct jffs2_acl_header)
+		       + 4 * sizeof(struct jffs2_acl_entry_short)
+		       + (count - 4) * sizeof(struct jffs2_acl_entry);
+	}
+}
+
+static int jffs2_acl_count(size_t size)
+{
+	size_t s;
+
+	size -= sizeof(struct jffs2_acl_header);
+	s = size - 4 * sizeof(struct jffs2_acl_entry_short);
+	if (s < 0) {
+		if (size % sizeof(struct jffs2_acl_entry_short))
+			return -1;
+		return size / sizeof(struct jffs2_acl_entry_short);
+	} else {
+		if (s % sizeof(struct jffs2_acl_entry))
+			return -1;
+		return s / sizeof(struct jffs2_acl_entry) + 4;
+	}
+}
+
+static struct posix_acl *jffs2_acl_from_medium(void *value, size_t size)
+{
+	void *end = value + size;
+	struct jffs2_acl_header *header = value;
+	struct jffs2_acl_entry *entry;
+	struct posix_acl *acl;
+	uint32_t ver;
+	int i, count;
+
+	if (!value)
+		return NULL;
+	if (size < sizeof(struct jffs2_acl_header))
+		return ERR_PTR(-EINVAL);
+	ver = je32_to_cpu(header->a_version);
+	if (ver != JFFS2_ACL_VERSION) {
+		JFFS2_WARNING("Invalid ACL version. (=%u)\n", ver);
+		return ERR_PTR(-EINVAL);
+	}
+
+	value += sizeof(struct jffs2_acl_header);
+	count = jffs2_acl_count(size);
+	if (count < 0)
+		return ERR_PTR(-EINVAL);
+	if (count == 0)
+		return NULL;
+
+	acl = posix_acl_alloc(count, GFP_KERNEL);
+	if (!acl)
+		return ERR_PTR(-ENOMEM);
+
+	for (i=0; i < count; i++) {
+		entry = value;
+		if (value + sizeof(struct jffs2_acl_entry_short) > end)
+			goto fail;
+		acl->a_entries[i].e_tag = je16_to_cpu(entry->e_tag);
+		acl->a_entries[i].e_perm = je16_to_cpu(entry->e_perm);
+		switch (acl->a_entries[i].e_tag) {
+			case ACL_USER_OBJ:
+			case ACL_GROUP_OBJ:
+			case ACL_MASK:
+			case ACL_OTHER:
+				value += sizeof(struct jffs2_acl_entry_short);
+				acl->a_entries[i].e_id = ACL_UNDEFINED_ID;
+				break;
+
+			case ACL_USER:
+			case ACL_GROUP:
+				value += sizeof(struct jffs2_acl_entry);
+				if (value > end)
+					goto fail;
+				acl->a_entries[i].e_id = je32_to_cpu(entry->e_id);
+				break;
+
+			default:
+				goto fail;
+		}
+	}
+	if (value != end)
+		goto fail;
+	return acl;
+ fail:
+	posix_acl_release(acl);
+	return ERR_PTR(-EINVAL);
+}
+
+static void *jffs2_acl_to_medium(const struct posix_acl *acl, size_t *size)
+{
+	struct jffs2_acl_header *header;
+	struct jffs2_acl_entry *entry;
+	void *e;
+	size_t i;
+
+	*size = jffs2_acl_size(acl->a_count);
+	header = kmalloc(sizeof(*header) + acl->a_count * sizeof(*entry), GFP_KERNEL);
+	if (!header)
+		return ERR_PTR(-ENOMEM);
+	header->a_version = cpu_to_je32(JFFS2_ACL_VERSION);
+	e = header + 1;
+	for (i=0; i < acl->a_count; i++) {
+		entry = e;
+		entry->e_tag = cpu_to_je16(acl->a_entries[i].e_tag);
+		entry->e_perm = cpu_to_je16(acl->a_entries[i].e_perm);
+		switch(acl->a_entries[i].e_tag) {
+			case ACL_USER:
+			case ACL_GROUP:
+				entry->e_id = cpu_to_je32(acl->a_entries[i].e_id);
+				e += sizeof(struct jffs2_acl_entry);
+				break;
+
+			case ACL_USER_OBJ:
+			case ACL_GROUP_OBJ:
+			case ACL_MASK:
+			case ACL_OTHER:
+				e += sizeof(struct jffs2_acl_entry_short);
+				break;
+
+			default:
+				goto fail;
+		}
+	}
+	return header;
+ fail:
+	kfree(header);
+	return ERR_PTR(-EINVAL);
+}
+
+static struct posix_acl *jffs2_iget_acl(struct inode *inode, struct posix_acl **i_acl)
+{
+	struct posix_acl *acl = JFFS2_ACL_NOT_CACHED;
+
+	spin_lock(&inode->i_lock);
+	if (*i_acl != JFFS2_ACL_NOT_CACHED)
+		acl = posix_acl_dup(*i_acl);
+	spin_unlock(&inode->i_lock);
+	return acl;
+}
+
+static void jffs2_iset_acl(struct inode *inode, struct posix_acl **i_acl, struct posix_acl *acl)
+{
+	spin_lock(&inode->i_lock);
+	if (*i_acl != JFFS2_ACL_NOT_CACHED)
+		posix_acl_release(*i_acl);
+	*i_acl = posix_acl_dup(acl);
+	spin_unlock(&inode->i_lock);
+}
+
+static struct posix_acl *jffs2_get_acl(struct inode *inode, int type)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct posix_acl *acl;
+	char *value = NULL;
+	int rc, xprefix;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		acl = jffs2_iget_acl(inode, &f->i_acl_access);
+		if (acl != JFFS2_ACL_NOT_CACHED)
+			return acl;
+		xprefix = JFFS2_XPREFIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		acl = jffs2_iget_acl(inode, &f->i_acl_default);
+		if (acl != JFFS2_ACL_NOT_CACHED)
+			return acl;
+		xprefix = JFFS2_XPREFIX_ACL_DEFAULT;
+		break;
+	default:
+		return ERR_PTR(-EINVAL);
+	}
+	rc = do_jffs2_getxattr(inode, xprefix, "", NULL, 0);
+	if (rc > 0) {
+		value = kmalloc(rc, GFP_KERNEL);
+		if (!value)
+			return ERR_PTR(-ENOMEM);
+		rc = do_jffs2_getxattr(inode, xprefix, "", value, rc);
+	}
+	if (rc > 0) {
+		acl = jffs2_acl_from_medium(value, rc);
+	} else if (rc == -ENODATA || rc == -ENOSYS) {
+		acl = NULL;
+	} else {
+		acl = ERR_PTR(rc);
+	}
+	if (value)
+		kfree(value);
+	if (!IS_ERR(acl)) {
+		switch (type) {
+		case ACL_TYPE_ACCESS:
+			jffs2_iset_acl(inode, &f->i_acl_access, acl);
+			break;
+		case ACL_TYPE_DEFAULT:
+			jffs2_iset_acl(inode, &f->i_acl_default, acl);
+			break;
+		}
+	}
+	return acl;
+}
+
+static int jffs2_set_acl(struct inode *inode, int type, struct posix_acl *acl)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	size_t size = 0;
+	char *value = NULL;
+	int rc, xprefix;
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		xprefix = JFFS2_XPREFIX_ACL_ACCESS;
+		if (acl) {
+			mode_t mode = inode->i_mode;
+			rc = posix_acl_equiv_mode(acl, &mode);
+			if (rc < 0)
+				return rc;
+			if (inode->i_mode != mode) {
+				inode->i_mode = mode;
+				jffs2_dirty_inode(inode);
+			}
+			if (rc == 0)
+				acl = NULL;
+		}
+		break;
+	case ACL_TYPE_DEFAULT:
+		xprefix = JFFS2_XPREFIX_ACL_DEFAULT;
+		if (!S_ISDIR(inode->i_mode))
+			return acl ? -EACCES : 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (acl) {
+		value = jffs2_acl_to_medium(acl, &size);
+		if (IS_ERR(value))
+			return PTR_ERR(value);
+	}
+
+	rc = do_jffs2_setxattr(inode, xprefix, "", value, size, 0);
+	if (value)
+		kfree(value);
+	if (!rc) {
+		switch(type) {
+		case ACL_TYPE_ACCESS:
+			jffs2_iset_acl(inode, &f->i_acl_access, acl);
+			break;
+		case ACL_TYPE_DEFAULT:
+			jffs2_iset_acl(inode, &f->i_acl_default, acl);
+			break;
+		}
+	}
+	return rc;
+}
+
+static int jffs2_check_acl(struct inode *inode, int mask)
+{
+	struct posix_acl *acl;
+	int rc;
+
+	acl = jffs2_get_acl(inode, ACL_TYPE_ACCESS);
+	if (IS_ERR(acl))
+		return PTR_ERR(acl);
+	if (acl) {
+		rc = posix_acl_permission(inode, acl, mask);
+		posix_acl_release(acl);
+		return rc;
+	}
+	return -EAGAIN;
+}
+
+int jffs2_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+	return generic_permission(inode, mask, jffs2_check_acl);
+}
+
+int jffs2_init_acl(struct inode *inode, struct inode *dir)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct posix_acl *acl = NULL, *clone;
+	mode_t mode;
+	int rc = 0;
+
+	f->i_acl_access = JFFS2_ACL_NOT_CACHED;
+	f->i_acl_default = JFFS2_ACL_NOT_CACHED;
+	if (!S_ISLNK(inode->i_mode)) {
+		acl = jffs2_get_acl(dir, ACL_TYPE_DEFAULT);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		if (!acl)
+			inode->i_mode &= ~current->fs->umask;
+	}
+	if (acl) {
+		if (S_ISDIR(inode->i_mode)) {
+			rc = jffs2_set_acl(inode, ACL_TYPE_DEFAULT, acl);
+			if (rc)
+				goto cleanup;
+		}
+		clone = posix_acl_clone(acl, GFP_KERNEL);
+		rc = -ENOMEM;
+		if (!clone)
+			goto cleanup;
+		mode = inode->i_mode;
+		rc = posix_acl_create_masq(clone, &mode);
+		if (rc >= 0) {
+			inode->i_mode = mode;
+			if (rc > 0)
+				rc = jffs2_set_acl(inode, ACL_TYPE_ACCESS, clone);
+		}
+		posix_acl_release(clone);
+	}
+ cleanup:
+	posix_acl_release(acl);
+	return rc;
+}
+
+void jffs2_clear_acl(struct inode *inode)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+
+	if (f->i_acl_access && f->i_acl_access != JFFS2_ACL_NOT_CACHED) {
+		posix_acl_release(f->i_acl_access);
+		f->i_acl_access = JFFS2_ACL_NOT_CACHED;
+	}
+	if (f->i_acl_default && f->i_acl_default != JFFS2_ACL_NOT_CACHED) {
+		posix_acl_release(f->i_acl_default);
+		f->i_acl_default = JFFS2_ACL_NOT_CACHED;
+	}
+}
+
+int jffs2_acl_chmod(struct inode *inode)
+{
+	struct posix_acl *acl, *clone;
+	int rc;
+
+	if (S_ISLNK(inode->i_mode))
+		return -EOPNOTSUPP;
+	acl = jffs2_get_acl(inode, ACL_TYPE_ACCESS);
+	if (IS_ERR(acl) || !acl)
+		return PTR_ERR(acl);
+	clone = posix_acl_clone(acl, GFP_KERNEL);
+	posix_acl_release(acl);
+	if (!clone)
+		return -ENOMEM;
+	rc = posix_acl_chmod_masq(clone, inode->i_mode);
+	if (!rc)
+		rc = jffs2_set_acl(inode, ACL_TYPE_ACCESS, clone);
+	posix_acl_release(clone);
+	return rc;
+}
+
+static size_t jffs2_acl_access_listxattr(struct inode *inode, char *list, size_t list_size,
+					 const char *name, size_t name_len)
+{
+	const int retlen = sizeof(POSIX_ACL_XATTR_ACCESS);
+
+	if (list && retlen <= list_size)
+		strcpy(list, POSIX_ACL_XATTR_ACCESS);
+	return retlen;
+}
+
+static size_t jffs2_acl_default_listxattr(struct inode *inode, char *list, size_t list_size,
+					  const char *name, size_t name_len)
+{
+	const int retlen = sizeof(POSIX_ACL_XATTR_DEFAULT);
+
+	if (list && retlen <= list_size)
+		strcpy(list, POSIX_ACL_XATTR_DEFAULT);
+	return retlen;
+}
+
+static int jffs2_acl_getxattr(struct inode *inode, int type, void *buffer, size_t size)
+{
+	struct posix_acl *acl;
+	int rc;
+
+	acl = jffs2_get_acl(inode, type);
+	if (IS_ERR(acl))
+		return PTR_ERR(acl);
+	if (!acl)
+		return -ENODATA;
+	rc = posix_acl_to_xattr(acl, buffer, size);
+	posix_acl_release(acl);
+
+	return rc;
+}
+
+static int jffs2_acl_access_getxattr(struct inode *inode, const char *name, void *buffer, size_t size)
+{
+	if (name[0] != '\0')
+		return -EINVAL;
+	return jffs2_acl_getxattr(inode, ACL_TYPE_ACCESS, buffer, size);
+}
+
+static int jffs2_acl_default_getxattr(struct inode *inode, const char *name, void *buffer, size_t size)
+{
+	if (name[0] != '\0')
+		return -EINVAL;
+	return jffs2_acl_getxattr(inode, ACL_TYPE_DEFAULT, buffer, size);
+}
+
+static int jffs2_acl_setxattr(struct inode *inode, int type, const void *value, size_t size)
+{
+	struct posix_acl *acl;
+	int rc;
+
+	if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+		return -EPERM;
+
+	if (value) {
+		acl = posix_acl_from_xattr(value, size);
+		if (IS_ERR(acl))
+			return PTR_ERR(acl);
+		if (acl) {
+			rc = posix_acl_valid(acl);
+			if (rc)
+				goto out;
+		}
+	} else {
+		acl = NULL;
+	}
+	rc = jffs2_set_acl(inode, type, acl);
+ out:
+	posix_acl_release(acl);
+	return rc;
+}
+
+static int jffs2_acl_access_setxattr(struct inode *inode, const char *name,
+				     const void *buffer, size_t size, int flags)
+{
+	if (name[0] != '\0')
+		return -EINVAL;
+	return jffs2_acl_setxattr(inode, ACL_TYPE_ACCESS, buffer, size);
+}
+
+static int jffs2_acl_default_setxattr(struct inode *inode, const char *name,
+				      const void *buffer, size_t size, int flags)
+{
+	if (name[0] != '\0')
+		return -EINVAL;
+	return jffs2_acl_setxattr(inode, ACL_TYPE_DEFAULT, buffer, size);
+}
+
+struct xattr_handler jffs2_acl_access_xattr_handler = {
+	.prefix	= POSIX_ACL_XATTR_ACCESS,
+	.list	= jffs2_acl_access_listxattr,
+	.get	= jffs2_acl_access_getxattr,
+	.set	= jffs2_acl_access_setxattr,
+};
+
+struct xattr_handler jffs2_acl_default_xattr_handler = {
+	.prefix	= POSIX_ACL_XATTR_DEFAULT,
+	.list	= jffs2_acl_default_listxattr,
+	.get	= jffs2_acl_default_getxattr,
+	.set	= jffs2_acl_default_setxattr,
+};

fs/jffs2/acl.h

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+struct jffs2_acl_entry {
+	jint16_t	e_tag;
+	jint16_t	e_perm;
+	jint32_t	e_id;
+};
+
+struct jffs2_acl_entry_short {
+	jint16_t	e_tag;
+	jint16_t	e_perm;
+};
+
+struct jffs2_acl_header {
+	jint32_t	a_version;
+};
+
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+
+#define JFFS2_ACL_NOT_CACHED ((void *)-1)
+
+extern int jffs2_permission(struct inode *, int, struct nameidata *);
+extern int jffs2_acl_chmod(struct inode *);
+extern int jffs2_init_acl(struct inode *, struct inode *);
+extern void jffs2_clear_acl(struct inode *);
+
+extern struct xattr_handler jffs2_acl_access_xattr_handler;
+extern struct xattr_handler jffs2_acl_default_xattr_handler;
+
+#else
+
+#define jffs2_permission NULL
+#define jffs2_acl_chmod(inode)		(0)
+#define jffs2_init_acl(inode,dir)	(0)
+#define jffs2_clear_acl(inode)
+
+#endif	/* CONFIG_JFFS2_FS_POSIX_ACL */

fs/jffs2/build.c

@@ -160,6 +160,7 @@ static int jffs2_build_filesystem(struct jffs2_sb_info *c)
 		ic->scan_dents = NULL;
 		cond_resched();
 	}
+	jffs2_build_xattr_subsystem(c);
 	c->flags &= ~JFFS2_SB_FLAG_BUILDING;
 
 	dbg_fsbuild("FS build complete\n");
@@ -178,6 +179,7 @@ static int jffs2_build_filesystem(struct jffs2_sb_info *c)
 				jffs2_free_full_dirent(fd);
 			}
 		}
+		jffs2_clear_xattr_subsystem(c);
 	}
 
 	return ret;

fs/jffs2/debug.h

@@ -171,6 +171,12 @@
 #define dbg_memalloc(fmt, ...)
 #endif
 
+/* Watch the XATTR subsystem */
+#ifdef JFFS2_DBG_XATTR_MESSAGES
+#define dbg_xattr(fmt, ...)  JFFS2_DEBUG(fmt, ##__VA_ARGS__)
+#else
+#define dbg_xattr(fmt, ...)
+#endif 
 
 /* "Sanity" checks */
 void

fs/jffs2/dir.c

@@ -57,7 +57,12 @@ struct inode_operations jffs2_dir_inode_operations =
 	.rmdir =	jffs2_rmdir,
 	.mknod =	jffs2_mknod,
 	.rename =	jffs2_rename,
+	.permission =	jffs2_permission,
 	.setattr =	jffs2_setattr,
+	.setxattr =	jffs2_setxattr,
+	.getxattr =	jffs2_getxattr,
+	.listxattr =	jffs2_listxattr,
+	.removexattr =	jffs2_removexattr
 };
 
 /***********************************************************************/
@@ -209,12 +214,15 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry, int mode,
 	ret = jffs2_do_create(c, dir_f, f, ri,
 			      dentry->d_name.name, dentry->d_name.len);
 
-	if (ret) {
-		make_bad_inode(inode);
-		iput(inode);
-		jffs2_free_raw_inode(ri);
-		return ret;
-	}
+	if (ret)
+		goto fail;
+
+	ret = jffs2_init_security(inode, dir_i);
+	if (ret)
+		goto fail;
+	ret = jffs2_init_acl(inode, dir_i);
+	if (ret)
+		goto fail;
 
 	dir_i->i_mtime = dir_i->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 
@@ -224,6 +232,12 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry, int mode,
 	D1(printk(KERN_DEBUG "jffs2_create: Created ino #%lu with mode %o, nlink %d(%d). nrpages %ld\n",
 		  inode->i_ino, inode->i_mode, inode->i_nlink, f->inocache->nlink, inode->i_mapping->nrpages));
 	return 0;
+
+ fail:
+	make_bad_inode(inode);
+	iput(inode);
+	jffs2_free_raw_inode(ri);
+	return ret;
 }
 
 /***********************************************************************/
@@ -374,6 +388,18 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char
 	up(&f->sem);
 
 	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+	ret = jffs2_init_acl(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+
 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,
 				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 	if (ret) {
@@ -504,6 +530,18 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, int mode)
 	up(&f->sem);
 
 	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+	ret = jffs2_init_acl(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+
 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,
 				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 	if (ret) {
@@ -658,6 +696,18 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, int mode, de
 	up(&f->sem);
 
 	jffs2_complete_reservation(c);
+
+	ret = jffs2_init_security(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+	ret = jffs2_init_acl(inode, dir_i);
+	if (ret) {
+		jffs2_clear_inode(inode);
+		return ret;
+	}
+
 	ret = jffs2_reserve_space(c, sizeof(*rd)+namelen, &phys_ofs, &alloclen,
 				ALLOC_NORMAL, JFFS2_SUMMARY_DIRENT_SIZE(namelen));
 	if (ret) {

fs/jffs2/file.c

@@ -54,7 +54,12 @@ const struct file_operations jffs2_file_operations =
 
 struct inode_operations jffs2_file_inode_operations =
 {
-	.setattr =	jffs2_setattr
+	.permission =	jffs2_permission,
+	.setattr =	jffs2_setattr,
+	.setxattr =	jffs2_setxattr,
+	.getxattr =	jffs2_getxattr,
+	.listxattr =	jffs2_listxattr,
+	.removexattr =	jffs2_removexattr
 };
 
 struct address_space_operations jffs2_file_address_operations =

fs/jffs2/fs.c

@@ -184,7 +184,12 @@ static int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
 
 int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
 {
-	return jffs2_do_setattr(dentry->d_inode, iattr);
+	int rc;
+
+	rc = jffs2_do_setattr(dentry->d_inode, iattr);
+	if (!rc && (iattr->ia_valid & ATTR_MODE))
+		rc = jffs2_acl_chmod(dentry->d_inode);
+	return rc;
 }
 
 int jffs2_statfs(struct super_block *sb, struct kstatfs *buf)
@@ -223,6 +228,7 @@ void jffs2_clear_inode (struct inode *inode)
 
 	D1(printk(KERN_DEBUG "jffs2_clear_inode(): ino #%lu mode %o\n", inode->i_ino, inode->i_mode));
 
+	jffs2_xattr_delete_inode(c, f->inocache);
 	jffs2_do_clear_inode(c, f);
 }
 
@@ -508,6 +514,8 @@ int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 	}
 	memset(c->inocache_list, 0, INOCACHE_HASHSIZE * sizeof(struct jffs2_inode_cache *));
 
+	jffs2_init_xattr_subsystem(c);
+
 	if ((ret = jffs2_do_mount_fs(c)))
 		goto out_inohash;
 
@@ -542,6 +550,7 @@ int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 	else
 		kfree(c->blocks);
  out_inohash:
+	jffs2_clear_xattr_subsystem(c);
 	kfree(c->inocache_list);
  out_wbuf:
 	jffs2_flash_cleanup(c);

fs/jffs2/gc.c

@@ -125,6 +125,7 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
 	struct jffs2_eraseblock *jeb;
 	struct jffs2_raw_node_ref *raw;
 	int ret = 0, inum, nlink;
+	int xattr = 0;
 
 	if (down_interruptible(&c->alloc_sem))
 		return -EINTR;
@@ -138,7 +139,7 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
 		   the node CRCs etc. Do it now. */
 
 		/* checked_ino is protected by the alloc_sem */
-		if (c->checked_ino > c->highest_ino) {
+		if (c->checked_ino > c->highest_ino && xattr) {
 			printk(KERN_CRIT "Checked all inodes but still 0x%x bytes of unchecked space?\n",
 			       c->unchecked_size);
 			jffs2_dbg_dump_block_lists_nolock(c);
@@ -148,6 +149,9 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
 
 		spin_unlock(&c->erase_completion_lock);
 
+		if (!xattr)
+			xattr = jffs2_verify_xattr(c);
+
 		spin_lock(&c->inocache_lock);
 
 		ic = jffs2_get_ino_cache(c, c->checked_ino++);
@@ -262,6 +266,23 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
 
 	ic = jffs2_raw_ref_to_ic(raw);
 
+#ifdef CONFIG_JFFS2_FS_XATTR
+	/* When 'ic' refers xattr_datum/xattr_ref, this node is GCed as xattr.
+	 * We can decide whether this node is inode or xattr by ic->class.     */
+	if (ic->class == RAWNODE_CLASS_XATTR_DATUM
+	    || ic->class == RAWNODE_CLASS_XATTR_REF) {
+		BUG_ON(raw->next_in_ino != (void *)ic);
+		spin_unlock(&c->erase_completion_lock);
+
+		if (ic->class == RAWNODE_CLASS_XATTR_DATUM) {
+			ret = jffs2_garbage_collect_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
+		} else {
+			ret = jffs2_garbage_collect_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
+		}
+		goto release_sem;
+	}
+#endif
+
 	/* We need to hold the inocache. Either the erase_completion_lock or
 	   the inocache_lock are sufficient; we trade down since the inocache_lock
 	   causes less contention. */

fs/jffs2/jffs2_fs_i.h

@@ -5,6 +5,7 @@
 
 #include <linux/version.h>
 #include <linux/rbtree.h>
+#include <linux/posix_acl.h>
 #include <asm/semaphore.h>
 
 struct jffs2_inode_info {
@@ -45,6 +46,10 @@ struct jffs2_inode_info {
 	struct inode vfs_inode;
 #endif
 #endif
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+	struct posix_acl *i_acl_access;
+	struct posix_acl *i_acl_default;
+#endif
 };
 
 #endif /* _JFFS2_FS_I */

fs/jffs2/jffs2_fs_sb.h

@@ -115,6 +115,16 @@ struct jffs2_sb_info {
 
 	struct jffs2_summary *summary;		/* Summary information */
 
+#ifdef CONFIG_JFFS2_FS_XATTR
+#define XATTRINDEX_HASHSIZE	(57)
+	uint32_t highest_xid;
+	struct list_head xattrindex[XATTRINDEX_HASHSIZE];
+	struct list_head xattr_unchecked;
+	struct jffs2_xattr_ref *xref_temp;
+	struct rw_semaphore xattr_sem;
+	uint32_t xdatum_mem_usage;
+	uint32_t xdatum_mem_threshold;
+#endif
 	/* OS-private pointer for getting back to master superblock info */
 	void *os_priv;
 };

fs/jffs2/malloc.c

@@ -26,6 +26,10 @@ static kmem_cache_t *tmp_dnode_info_slab;
 static kmem_cache_t *raw_node_ref_slab;
 static kmem_cache_t *node_frag_slab;
 static kmem_cache_t *inode_cache_slab;
+#ifdef CONFIG_JFFS2_FS_XATTR
+static kmem_cache_t *xattr_datum_cache;
+static kmem_cache_t *xattr_ref_cache;
+#endif
 
 int __init jffs2_create_slab_caches(void)
 {
@@ -68,8 +72,24 @@ int __init jffs2_create_slab_caches(void)
 	inode_cache_slab = kmem_cache_create("jffs2_inode_cache",
 					     sizeof(struct jffs2_inode_cache),
 					     0, 0, NULL, NULL);
-	if (inode_cache_slab)
-		return 0;
+	if (!inode_cache_slab)
+		goto err;
+
+#ifdef CONFIG_JFFS2_FS_XATTR
+	xattr_datum_cache = kmem_cache_create("jffs2_xattr_datum",
+					     sizeof(struct jffs2_xattr_datum),
+					     0, 0, NULL, NULL);
+	if (!xattr_datum_cache)
+		goto err;
+
+	xattr_ref_cache = kmem_cache_create("jffs2_xattr_ref",
+					   sizeof(struct jffs2_xattr_ref),
+					   0, 0, NULL, NULL);
+	if (!xattr_ref_cache)
+		goto err;
+#endif
+
+	return 0;
  err:
 	jffs2_destroy_slab_caches();
 	return -ENOMEM;
@@ -91,6 +111,12 @@ void jffs2_destroy_slab_caches(void)
 		kmem_cache_destroy(node_frag_slab);
 	if(inode_cache_slab)
 		kmem_cache_destroy(inode_cache_slab);
+#ifdef CONFIG_JFFS2_FS_XATTR
+	if (xattr_datum_cache)
+		kmem_cache_destroy(xattr_datum_cache);
+	if (xattr_ref_cache)
+		kmem_cache_destroy(xattr_ref_cache);
+#endif
 }
 
 struct jffs2_full_dirent *jffs2_alloc_full_dirent(int namesize)
@@ -205,3 +231,40 @@ void jffs2_free_inode_cache(struct jffs2_inode_cache *x)
 	dbg_memalloc("%p\n", x);
 	kmem_cache_free(inode_cache_slab, x);
 }
+
+#ifdef CONFIG_JFFS2_FS_XATTR
+struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void)
+{
+	struct jffs2_xattr_datum *xd;
+	xd = kmem_cache_alloc(xattr_datum_cache, GFP_KERNEL);
+	dbg_memalloc("%p\n", xd);
+
+	memset(xd, 0, sizeof(struct jffs2_xattr_datum));
+	xd->class = RAWNODE_CLASS_XATTR_DATUM;
+	INIT_LIST_HEAD(&xd->xindex);
+	return xd;
+}
+
+void jffs2_free_xattr_datum(struct jffs2_xattr_datum *xd)
+{
+	dbg_memalloc("%p\n", xd);
+	kmem_cache_free(xattr_datum_cache, xd);
+}
+
+struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void)
+{
+	struct jffs2_xattr_ref *ref;
+	ref = kmem_cache_alloc(xattr_ref_cache, GFP_KERNEL);
+	dbg_memalloc("%p\n", ref);
+
+	memset(ref, 0, sizeof(struct jffs2_xattr_ref));
+	ref->class = RAWNODE_CLASS_XATTR_REF;
+	return ref;
+}
+
+void jffs2_free_xattr_ref(struct jffs2_xattr_ref *ref)
+{
+	dbg_memalloc("%p\n", ref);
+	kmem_cache_free(xattr_ref_cache, ref);
+}
+#endif

fs/jffs2/nodelist.c

@@ -938,6 +938,7 @@ void jffs2_free_ino_caches(struct jffs2_sb_info *c)
 		this = c->inocache_list[i];
 		while (this) {
 			next = this->next;
+			jffs2_xattr_free_inode(c, this);
 			jffs2_free_inode_cache(this);
 			this = next;
 		}

fs/jffs2/nodelist.h

@@ -20,6 +20,8 @@
 #include <linux/jffs2.h>
 #include "jffs2_fs_sb.h"
 #include "jffs2_fs_i.h"
+#include "xattr.h"
+#include "acl.h"
 #include "summary.h"
 
 #ifdef __ECOS
@@ -107,11 +109,16 @@ struct jffs2_inode_cache {
 		temporary lists of dirents, and later must be set to
 		NULL to mark the end of the raw_node_ref->next_in_ino
 		chain. */
+	u8 class;	/* It's used for identification */
+	u8 flags;
+	uint16_t state;
 	struct jffs2_inode_cache *next;
 	struct jffs2_raw_node_ref *nodes;
 	uint32_t ino;
 	int nlink;
-	int state;
+#ifdef CONFIG_JFFS2_FS_XATTR
+	struct jffs2_xattr_ref *xref;
+#endif
 };
 
 /* Inode states for 'state' above. We need the 'GC' state to prevent
@@ -125,6 +132,12 @@ struct jffs2_inode_cache {
 #define INO_STATE_READING	5	/* In read_inode() */
 #define INO_STATE_CLEARING	6	/* In clear_inode() */
 
+#define INO_FLAGS_XATTR_CHECKED	0x01	/* has no duplicate xattr_ref */
+
+#define RAWNODE_CLASS_INODE_CACHE	0
+#define RAWNODE_CLASS_XATTR_DATUM	1
+#define RAWNODE_CLASS_XATTR_REF		2
+
 #define INOCACHE_HASHSIZE 128
 
 /*
@@ -385,6 +398,12 @@ struct jffs2_node_frag *jffs2_alloc_node_frag(void);
 void jffs2_free_node_frag(struct jffs2_node_frag *);
 struct jffs2_inode_cache *jffs2_alloc_inode_cache(void);
 void jffs2_free_inode_cache(struct jffs2_inode_cache *);
+#ifdef CONFIG_JFFS2_FS_XATTR
+struct jffs2_xattr_datum *jffs2_alloc_xattr_datum(void);
+void jffs2_free_xattr_datum(struct jffs2_xattr_datum *);
+struct jffs2_xattr_ref *jffs2_alloc_xattr_ref(void);
+void jffs2_free_xattr_ref(struct jffs2_xattr_ref *);
+#endif
 
 /* gc.c */
 int jffs2_garbage_collect_pass(struct jffs2_sb_info *c);

fs/jffs2/os-linux.h

@@ -58,6 +58,10 @@ static inline void jffs2_init_inode_info(struct jffs2_inode_info *f)
 	f->target = NULL;
 	f->flags = 0;
 	f->usercompr = 0;
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+	f->i_acl_access = JFFS2_ACL_NOT_CACHED;
+	f->i_acl_default = JFFS2_ACL_NOT_CACHED;
+#endif
 }
 
 

fs/jffs2/scan.c

@@ -306,6 +306,137 @@ int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *je
 		return BLK_STATE_ALLDIRTY;
 }
 
+#ifdef CONFIG_JFFS2_FS_XATTR
+static int jffs2_scan_xattr_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				 struct jffs2_raw_xattr *rx, uint32_t ofs,
+				 struct jffs2_summary *s)
+{
+	struct jffs2_xattr_datum *xd;
+	struct jffs2_raw_node_ref *raw;
+	uint32_t totlen, crc;
+
+	crc = crc32(0, rx, sizeof(struct jffs2_raw_xattr) - 4);
+	if (crc != je32_to_cpu(rx->node_crc)) {
+		if (je32_to_cpu(rx->node_crc) != 0xffffffff)
+			JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+				      ofs, je32_to_cpu(rx->node_crc), crc);
+		DIRTY_SPACE(je32_to_cpu(rx->totlen));
+		return 0;
+	}
+
+	totlen = PAD(sizeof(*rx) + rx->name_len + 1 + je16_to_cpu(rx->value_len));
+	if (totlen != je32_to_cpu(rx->totlen)) {
+		JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n",
+			      ofs, je32_to_cpu(rx->totlen), totlen);
+		DIRTY_SPACE(je32_to_cpu(rx->totlen));
+		return 0;
+	}
+
+	raw =  jffs2_alloc_raw_node_ref();
+	if (!raw)
+		return -ENOMEM;
+
+	xd = jffs2_setup_xattr_datum(c, je32_to_cpu(rx->xid), je32_to_cpu(rx->version));
+	if (IS_ERR(xd)) {
+		jffs2_free_raw_node_ref(raw);
+		if (PTR_ERR(xd) == -EEXIST) {
+			DIRTY_SPACE(PAD(je32_to_cpu(rx->totlen)));
+			return 0;
+		}
+		return PTR_ERR(xd);
+	}
+	xd->xprefix = rx->xprefix;
+	xd->name_len = rx->name_len;
+	xd->value_len = je16_to_cpu(rx->value_len);
+	xd->data_crc = je32_to_cpu(rx->data_crc);
+	xd->node = raw;
+
+	raw->__totlen = totlen;
+	raw->flash_offset = ofs | REF_PRISTINE;
+	raw->next_phys = NULL;
+	raw->next_in_ino = (void *)xd;
+	if (!jeb->first_node)
+		jeb->first_node = raw;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = raw;
+	jeb->last_node = raw;
+
+	USED_SPACE(PAD(je32_to_cpu(rx->totlen)));
+	if (jffs2_sum_active())
+		jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset);
+	dbg_xattr("scaning xdatum at %#08x (xid=%u, version=%u)\n",
+		  ofs, xd->xid, xd->version);
+	return 0;
+}
+
+static int jffs2_scan_xref_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
+				struct jffs2_raw_xref *rr, uint32_t ofs,
+				struct jffs2_summary *s)
+{
+	struct jffs2_xattr_ref *ref;
+	struct jffs2_raw_node_ref *raw;
+	uint32_t crc;
+
+	crc = crc32(0, rr, sizeof(*rr) - 4);
+	if (crc != je32_to_cpu(rr->node_crc)) {
+		if (je32_to_cpu(rr->node_crc) != 0xffffffff)
+			JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+				      ofs, je32_to_cpu(rr->node_crc), crc);
+		DIRTY_SPACE(PAD(je32_to_cpu(rr->totlen)));
+		return 0;
+	}
+
+	if (PAD(sizeof(struct jffs2_raw_xref)) != je32_to_cpu(rr->totlen)) {
+		JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n",
+			      ofs, je32_to_cpu(rr->totlen),
+			      PAD(sizeof(struct jffs2_raw_xref)));
+		DIRTY_SPACE(je32_to_cpu(rr->totlen));
+		return 0;
+	}
+
+	ref = jffs2_alloc_xattr_ref();
+	if (!ref)
+		return -ENOMEM;
+
+	raw =  jffs2_alloc_raw_node_ref();
+	if (!raw) {
+		jffs2_free_xattr_ref(ref);
+		return -ENOMEM;
+	}
+
+	/* BEFORE jffs2_build_xattr_subsystem() called, 
+	 * ref->xid is used to store 32bit xid, xd is not used
+	 * ref->ino is used to store 32bit inode-number, ic is not used
+	 * Thoes variables are declared as union, thus using those
+	 * are exclusive. In a similar way, ref->next is temporarily
+	 * used to chain all xattr_ref object. It's re-chained to
+	 * jffs2_inode_cache in jffs2_build_xattr_subsystem() correctly.
+	 */
+	ref->node = raw;
+	ref->ino = je32_to_cpu(rr->ino);
+	ref->xid = je32_to_cpu(rr->xid);
+	ref->next = c->xref_temp;
+	c->xref_temp = ref;
+
+	raw->__totlen = PAD(je32_to_cpu(rr->totlen));
+	raw->flash_offset = ofs | REF_PRISTINE;
+	raw->next_phys = NULL;
+	raw->next_in_ino = (void *)ref;
+	if (!jeb->first_node)
+		jeb->first_node = raw;
+	if (jeb->last_node)
+		jeb->last_node->next_phys = raw;
+	jeb->last_node = raw;
+
+	USED_SPACE(PAD(je32_to_cpu(rr->totlen)));	
+	if (jffs2_sum_active())
+		jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset);
+	dbg_xattr("scan xref at %#08x (xid=%u, ino=%u)\n",
+		  ofs, ref->xid, ref->ino);
+	return 0;
+}
+#endif
+
 /* Called with 'buf_size == 0' if buf is in fact a pointer _directly_ into
    the flash, XIP-style */
 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
@@ -641,6 +772,43 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
 			ofs += PAD(je32_to_cpu(node->totlen));
 			break;
 
+#ifdef CONFIG_JFFS2_FS_XATTR
+		case JFFS2_NODETYPE_XATTR:
+			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
+				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
+				D1(printk(KERN_DEBUG "Fewer than %d bytes (xattr node)"
+					  " left to end of buf. Reading 0x%x at 0x%08x\n",
+					  je32_to_cpu(node->totlen), buf_len, ofs));
+				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
+				if (err)
+					return err;
+				buf_ofs = ofs;
+				node = (void *)buf;
+			}
+			err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s);
+			if (err)
+				return err;
+			ofs += PAD(je32_to_cpu(node->totlen));
+			break;
+		case JFFS2_NODETYPE_XREF:
+			if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
+				buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
+				D1(printk(KERN_DEBUG "Fewer than %d bytes (xref node)"
+					  " left to end of buf. Reading 0x%x at 0x%08x\n",
+					  je32_to_cpu(node->totlen), buf_len, ofs));
+				err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
+				if (err)
+					return err;
+				buf_ofs = ofs;
+				node = (void *)buf;
+			}
+			err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s);
+			if (err)
+				return err;
+			ofs += PAD(je32_to_cpu(node->totlen));
+			break;
+#endif	/* CONFIG_JFFS2_FS_XATTR */
+
 		case JFFS2_NODETYPE_CLEANMARKER:
 			D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
 			if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {

fs/jffs2/security.c

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/crc32.h>
+#include <linux/jffs2.h>
+#include <linux/xattr.h>
+#include <linux/mtd/mtd.h>
+#include <linux/security.h>
+#include "nodelist.h"
+
+/* ---- Initial Security Label Attachment -------------- */
+int jffs2_init_security(struct inode *inode, struct inode *dir)
+{
+	int rc;
+	size_t len;
+	void *value;
+	char *name;
+
+	rc = security_inode_init_security(inode, dir, &name, &value, &len);
+	if (rc) {
+		if (rc == -EOPNOTSUPP)
+			return 0;
+		return rc;
+	}
+	rc = do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, name, value, len, 0);
+
+        kfree(name);
+        kfree(value);
+        return rc;
+}
+
+/* ---- XATTR Handler for "security.*" ----------------- */
+static int jffs2_security_getxattr(struct inode *inode, const char *name,
+				   void *buffer, size_t size)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	return do_jffs2_getxattr(inode, JFFS2_XPREFIX_SECURITY, name, buffer, size);
+}
+
+static int jffs2_security_setxattr(struct inode *inode, const char *name, const void *buffer,
+				   size_t size, int flags)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	return do_jffs2_setxattr(inode, JFFS2_XPREFIX_SECURITY, name, buffer, size, flags);
+}
+
+static size_t jffs2_security_listxattr(struct inode *inode, char *list, size_t list_size,
+				       const char *name, size_t name_len)
+{
+	size_t retlen = XATTR_SECURITY_PREFIX_LEN + name_len + 1;
+
+	if (list && retlen <= list_size) {
+		strcpy(list, XATTR_SECURITY_PREFIX);
+		strcpy(list + XATTR_SECURITY_PREFIX_LEN, name);
+	}
+
+	return retlen;
+}
+
+struct xattr_handler jffs2_security_xattr_handler = {
+	.prefix = XATTR_SECURITY_PREFIX,
+	.list = jffs2_security_listxattr,
+	.set = jffs2_security_setxattr,
+	.get = jffs2_security_getxattr
+};

fs/jffs2/summary.c

@@ -5,6 +5,7 @@
  *                     Zoltan Sogor <weth@inf.u-szeged.hu>,
  *                     Patrik Kluba <pajko@halom.u-szeged.hu>,
  *                     University of Szeged, Hungary
+ *               2005  KaiGai Kohei <kaigai@ak.jp.nec.com>
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
@@ -81,6 +82,19 @@ static int jffs2_sum_add_mem(struct jffs2_summary *s, union jffs2_sum_mem *item)
 			dbg_summary("dirent (%u) added to summary\n",
 						je32_to_cpu(item->d.ino));
 			break;
+#ifdef CONFIG_JFFS2_FS_XATTR
+		case JFFS2_NODETYPE_XATTR:
+			s->sum_size += JFFS2_SUMMARY_XATTR_SIZE;
+			s->sum_num++;
+			dbg_summary("xattr (xid=%u, version=%u) added to summary\n",
+				    je32_to_cpu(item->x.xid), je32_to_cpu(item->x.version));
+			break;
+		case JFFS2_NODETYPE_XREF:
+			s->sum_size += JFFS2_SUMMARY_XREF_SIZE;
+			s->sum_num++;
+			dbg_summary("xref added to summary\n");
+			break;
+#endif
 		default:
 			JFFS2_WARNING("UNKNOWN node type %u\n",
 					    je16_to_cpu(item->u.nodetype));
@@ -141,6 +155,40 @@ int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *r
 	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
 }
 
+#ifdef CONFIG_JFFS2_FS_XATTR
+int jffs2_sum_add_xattr_mem(struct jffs2_summary *s, struct jffs2_raw_xattr *rx, uint32_t ofs)
+{
+	struct jffs2_sum_xattr_mem *temp;
+
+	temp = kmalloc(sizeof(struct jffs2_sum_xattr_mem), GFP_KERNEL);
+	if (!temp)
+		return -ENOMEM;
+
+	temp->nodetype = rx->nodetype;
+	temp->xid = rx->xid;
+	temp->version = rx->version;
+	temp->offset = cpu_to_je32(ofs);
+	temp->totlen = rx->totlen;
+	temp->next = NULL;
+
+	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
+}
+
+int jffs2_sum_add_xref_mem(struct jffs2_summary *s, struct jffs2_raw_xref *rr, uint32_t ofs)
+{
+	struct jffs2_sum_xref_mem *temp;
+
+	temp = kmalloc(sizeof(struct jffs2_sum_xref_mem), GFP_KERNEL);
+	if (!temp)
+		return -ENOMEM;
+
+	temp->nodetype = rr->nodetype;
+	temp->offset = cpu_to_je32(ofs);
+	temp->next = NULL;
+
+	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
+}
+#endif
 /* Cleanup every collected summary information */
 
 static void jffs2_sum_clean_collected(struct jffs2_summary *s)
@@ -259,7 +307,40 @@ int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
 
 			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
 		}
+#ifdef CONFIG_JFFS2_FS_XATTR
+		case JFFS2_NODETYPE_XATTR: {
+			struct jffs2_sum_xattr_mem *temp;
+			if (je32_to_cpu(node->x.version) == 0xffffffff)
+				return 0;
+			temp = kmalloc(sizeof(struct jffs2_sum_xattr_mem), GFP_KERNEL);
+			if (!temp)
+				goto no_mem;
 
+			temp->nodetype = node->x.nodetype;
+			temp->xid = node->x.xid;
+			temp->version = node->x.version;
+			temp->totlen = node->x.totlen;
+			temp->offset = cpu_to_je32(ofs);
+			temp->next = NULL;
+
+			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
+		}
+		case JFFS2_NODETYPE_XREF: {
+			struct jffs2_sum_xref_mem *temp;
+
+			if (je32_to_cpu(node->r.ino) == 0xffffffff
+			    && je32_to_cpu(node->r.xid) == 0xffffffff)
+				return 0;
+			temp = kmalloc(sizeof(struct jffs2_sum_xref_mem), GFP_KERNEL);
+			if (!temp)
+				goto no_mem;
+			temp->nodetype = node->r.nodetype;
+			temp->offset = cpu_to_je32(ofs);
+			temp->next = NULL;
+
+			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
+		}
+#endif
 		case JFFS2_NODETYPE_PADDING:
 			dbg_summary("node PADDING\n");
 			c->summary->sum_padded += je32_to_cpu(node->u.totlen);
@@ -402,8 +483,101 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
 
 				break;
 			}
+#ifdef CONFIG_JFFS2_FS_XATTR
+			case JFFS2_NODETYPE_XATTR: {
+				struct jffs2_xattr_datum *xd;
+				struct jffs2_sum_xattr_flash *spx;
+				uint32_t ofs;
+
+				spx = (struct jffs2_sum_xattr_flash *)sp;
+				ofs = jeb->offset + je32_to_cpu(spx->offset);
+				dbg_summary("xattr at %#08x (xid=%u, version=%u)\n", ofs,
+					    je32_to_cpu(spx->xid), je32_to_cpu(spx->version));
+				raw = jffs2_alloc_raw_node_ref();
+				if (!raw) {
+					JFFS2_NOTICE("allocation of node reference failed\n");
+					kfree(summary);
+					return -ENOMEM;
+				}
+				xd = jffs2_setup_xattr_datum(c, je32_to_cpu(spx->xid),
+								je32_to_cpu(spx->version));
+				if (IS_ERR(xd)) {
+					jffs2_free_raw_node_ref(raw);
+					if (PTR_ERR(xd) == -EEXIST) {
+						/* a newer version of xd exists */
+						DIRTY_SPACE(je32_to_cpu(spx->totlen));
+						sp += JFFS2_SUMMARY_XATTR_SIZE;
+						break;
+					}
+					JFFS2_NOTICE("allocation of xattr_datum failed\n");
+					kfree(summary);
+					return PTR_ERR(xd);
+				}
+				xd->node = raw;
+
+				raw->flash_offset = ofs | REF_UNCHECKED;
+				raw->__totlen = PAD(je32_to_cpu(spx->totlen));
+				raw->next_phys = NULL;
+				raw->next_in_ino = (void *)xd;
+				if (!jeb->first_node)
+					jeb->first_node = raw;
+				if (jeb->last_node)
+					jeb->last_node->next_phys = raw;
+				jeb->last_node = raw;
+
+				*pseudo_random += je32_to_cpu(spx->xid);
+				UNCHECKED_SPACE(je32_to_cpu(spx->totlen));
+				sp += JFFS2_SUMMARY_XATTR_SIZE;
+
+				break;
+			}
+			case JFFS2_NODETYPE_XREF: {
+				struct jffs2_xattr_ref *ref;
+				struct jffs2_sum_xref_flash *spr;
+				uint32_t ofs;
+
+				spr = (struct jffs2_sum_xref_flash *)sp;
+				ofs = jeb->offset + je32_to_cpu(spr->offset);
+				dbg_summary("xref at %#08x (xid=%u, ino=%u)\n", ofs,
+					    je32_to_cpu(spr->xid), je32_to_cpu(spr->ino));
+				raw = jffs2_alloc_raw_node_ref();
+				if (!raw) {
+					JFFS2_NOTICE("allocation of node reference failed\n");
+					kfree(summary);
+					return -ENOMEM;
+				}
+				ref = jffs2_alloc_xattr_ref();
+				if (!ref) {
+					JFFS2_NOTICE("allocation of xattr_datum failed\n");
+					jffs2_free_raw_node_ref(raw);
+					kfree(summary);
+					return -ENOMEM;
+				}
+				ref->ino = 0xfffffffe;
+				ref->xid = 0xfffffffd;
+				ref->node = raw;
+				ref->next = c->xref_temp;
+				c->xref_temp = ref;
+
+				raw->__totlen = PAD(sizeof(struct jffs2_raw_xref));
+				raw->flash_offset = ofs | REF_UNCHECKED;
+				raw->next_phys = NULL;
+				raw->next_in_ino = (void *)ref;
+				if (!jeb->first_node)
+					jeb->first_node = raw;
+				if (jeb->last_node)
+					jeb->last_node->next_phys = raw;
+				jeb->last_node = raw;
+
+				UNCHECKED_SPACE(PAD(sizeof(struct jffs2_raw_xref)));
+				*pseudo_random += ofs;
+				sp += JFFS2_SUMMARY_XREF_SIZE;
 
+				break;
+			}
+#endif
 			default : {
+printk("nodetype = %#04x\n",je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype));
 				JFFS2_WARNING("Unsupported node type found in summary! Exiting...");
 				return -EIO;
 			}
@@ -593,7 +767,31 @@ static int jffs2_sum_write_data(struct jffs2_sb_info *c, struct jffs2_eraseblock
 
 				break;
 			}
+#ifdef CONFIG_JFFS2_FS_XATTR
+			case JFFS2_NODETYPE_XATTR: {
+				struct jffs2_sum_xattr_flash *sxattr_ptr = wpage;
+
+				temp = c->summary->sum_list_head;
+				sxattr_ptr->nodetype = temp->x.nodetype;
+				sxattr_ptr->xid = temp->x.xid;
+				sxattr_ptr->version = temp->x.version;
+				sxattr_ptr->offset = temp->x.offset;
+				sxattr_ptr->totlen = temp->x.totlen;
+
+				wpage += JFFS2_SUMMARY_XATTR_SIZE;
+				break;
+			}
+			case JFFS2_NODETYPE_XREF: {
+				struct jffs2_sum_xref_flash *sxref_ptr = wpage;
+
+				temp = c->summary->sum_list_head;
+				sxref_ptr->nodetype = temp->r.nodetype;
+				sxref_ptr->offset = temp->r.offset;
 
+				wpage += JFFS2_SUMMARY_XREF_SIZE;
+				break;
+			}
+#endif
 			default : {
 				BUG();	/* unknown node in summary information */
 			}

fs/jffs2/summary.h

@@ -45,6 +45,8 @@
 #define JFFS2_SUMMARY_NOSUM_SIZE 0xffffffff
 #define JFFS2_SUMMARY_INODE_SIZE (sizeof(struct jffs2_sum_inode_flash))
 #define JFFS2_SUMMARY_DIRENT_SIZE(x) (sizeof(struct jffs2_sum_dirent_flash) + (x))
+#define JFFS2_SUMMARY_XATTR_SIZE (sizeof(struct jffs2_sum_xattr_flash))
+#define JFFS2_SUMMARY_XREF_SIZE (sizeof(struct jffs2_sum_xref_flash))
 
 /* Summary structures used on flash */
 
@@ -75,11 +77,28 @@ struct jffs2_sum_dirent_flash
 	uint8_t name[0];	/* dirent name */
 } __attribute__((packed));
 
+struct jffs2_sum_xattr_flash
+{
+	jint16_t nodetype;	/* == JFFS2_NODETYPE_XATR */
+	jint32_t xid;		/* xattr identifier */
+	jint32_t version;	/* version number */
+	jint32_t offset;	/* offset on jeb */
+	jint32_t totlen;	/* node length */
+} __attribute__((packed));
+
+struct jffs2_sum_xref_flash
+{
+	jint16_t nodetype;	/* == JFFS2_NODETYPE_XREF */
+	jint32_t offset;	/* offset on jeb */
+} __attribute__((packed));
+
 union jffs2_sum_flash
 {
 	struct jffs2_sum_unknown_flash u;
 	struct jffs2_sum_inode_flash i;
 	struct jffs2_sum_dirent_flash d;
+	struct jffs2_sum_xattr_flash x;
+	struct jffs2_sum_xref_flash r;
 };
 
 /* Summary structures used in the memory */
@@ -114,11 +133,30 @@ struct jffs2_sum_dirent_mem
 	uint8_t name[0];	/* dirent name */
 } __attribute__((packed));
 
+struct jffs2_sum_xattr_mem
+{
+	union jffs2_sum_mem *next;
+	jint16_t nodetype;
+	jint32_t xid;
+	jint32_t version;
+	jint32_t offset;
+	jint32_t totlen;
+} __attribute__((packed));
+
+struct jffs2_sum_xref_mem
+{
+	union jffs2_sum_mem *next;
+	jint16_t nodetype;
+	jint32_t offset;
+} __attribute__((packed));
+
 union jffs2_sum_mem
 {
 	struct jffs2_sum_unknown_mem u;
 	struct jffs2_sum_inode_mem i;
 	struct jffs2_sum_dirent_mem d;
+	struct jffs2_sum_xattr_mem x;
+	struct jffs2_sum_xref_mem r;
 };
 
 /* Summary related information stored in superblock */
@@ -159,6 +197,8 @@ int jffs2_sum_write_sumnode(struct jffs2_sb_info *c);
 int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size);
 int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri, uint32_t ofs);
 int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd, uint32_t ofs);
+int jffs2_sum_add_xattr_mem(struct jffs2_summary *s, struct jffs2_raw_xattr *rx, uint32_t ofs);
+int jffs2_sum_add_xref_mem(struct jffs2_summary *s, struct jffs2_raw_xref *rr, uint32_t ofs);
 int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
 			   struct jffs2_raw_summary *summary, uint32_t sumlen,
 			   uint32_t *pseudo_random);
@@ -177,6 +217,8 @@ int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb
 #define jffs2_sum_add_padding_mem(a,b)
 #define jffs2_sum_add_inode_mem(a,b,c)
 #define jffs2_sum_add_dirent_mem(a,b,c)
+#define jffs2_sum_add_xattr_mem(a,b,c)
+#define jffs2_sum_add_xref_mem(a,b,c)
 #define jffs2_sum_scan_sumnode(a,b,c,d) (0)
 
 #endif /* CONFIG_JFFS2_SUMMARY */

fs/jffs2/super.c

@@ -151,7 +151,10 @@ static struct super_block *jffs2_get_sb_mtd(struct file_system_type *fs_type,
 
 	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) {
@@ -293,6 +296,7 @@ static void jffs2_put_super (struct super_block *sb)
 		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);
 

fs/jffs2/symlink.c

@@ -24,7 +24,12 @@ struct inode_operations jffs2_symlink_inode_operations =
 {
 	.readlink =	generic_readlink,
 	.follow_link =	jffs2_follow_link,
-	.setattr =	jffs2_setattr
+	.permission =	jffs2_permission,
+	.setattr =	jffs2_setattr,
+	.setxattr =	jffs2_setxattr,
+	.getxattr =	jffs2_getxattr,
+	.listxattr =	jffs2_listxattr,
+	.removexattr =	jffs2_removexattr
 };
 
 static void *jffs2_follow_link(struct dentry *dentry, struct nameidata *nd)

fs/jffs2/write.c

@@ -37,7 +37,6 @@ int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint
 	f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache;
 	f->inocache->state = INO_STATE_PRESENT;
 
-
 	jffs2_add_ino_cache(c, f->inocache);
 	D1(printk(KERN_DEBUG "jffs2_do_new_inode(): Assigned ino# %d\n", f->inocache->ino));
 	ri->ino = cpu_to_je32(f->inocache->ino);

fs/jffs2/xattr.c

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/crc32.h>
+#include <linux/jffs2.h>
+#include <linux/xattr.h>
+#include <linux/mtd/mtd.h>
+#include "nodelist.h"
+/* -------- xdatum related functions ----------------
+ * xattr_datum_hashkey(xprefix, xname, xvalue, xsize)
+ *   is used to calcurate xdatum hashkey. The reminder of hashkey into XATTRINDEX_HASHSIZE is
+ *   the index of the xattr name/value pair cache (c->xattrindex).
+ * unload_xattr_datum(c, xd)
+ *   is used to release xattr name/value pair and detach from c->xattrindex.
+ * reclaim_xattr_datum(c)
+ *   is used to reclaim xattr name/value pairs on the xattr name/value pair cache when
+ *   memory usage by cache is over c->xdatum_mem_threshold. Currentry, this threshold 
+ *   is hard coded as 32KiB.
+ * delete_xattr_datum_node(c, xd)
+ *   is used to delete a jffs2 node is dominated by xdatum. When EBS(Erase Block Summary) is
+ *   enabled, it overwrites the obsolete node by myself.
+ * delete_xattr_datum(c, xd)
+ *   is used to delete jffs2_xattr_datum object. It must be called with 0-value of reference
+ *   counter. (It means how many jffs2_xattr_ref object refers this xdatum.)
+ * do_verify_xattr_datum(c, xd)
+ *   is used to load the xdatum informations without name/value pair from the medium.
+ *   It's necessary once, because those informations are not collected during mounting
+ *   process when EBS is enabled.
+ *   0 will be returned, if success. An negative return value means recoverable error, and
+ *   positive return value means unrecoverable error. Thus, caller must remove this xdatum
+ *   and xref when it returned positive value.
+ * do_load_xattr_datum(c, xd)
+ *   is used to load name/value pair from the medium.
+ *   The meanings of return value is same as do_verify_xattr_datum().
+ * load_xattr_datum(c, xd)
+ *   is used to be as a wrapper of do_verify_xattr_datum() and do_load_xattr_datum().
+ *   If xd need to call do_verify_xattr_datum() at first, it's called before calling
+ *   do_load_xattr_datum(). The meanings of return value is same as do_verify_xattr_datum().
+ * save_xattr_datum(c, xd, phys_ofs)
+ *   is used to write xdatum to medium. xd->version will be incremented.
+ * create_xattr_datum(c, xprefix, xname, xvalue, xsize, phys_ofs)
+ *   is used to create new xdatum and write to medium.
+ * -------------------------------------------------- */
+
+static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
+{
+	int name_len = strlen(xname);
+
+	return crc32(xprefix, xname, name_len) ^ crc32(xprefix, xvalue, xsize);
+}
+
+static void unload_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem) */
+	D1(dbg_xattr("%s: xid=%u, version=%u\n", __FUNCTION__, xd->xid, xd->version));
+	if (xd->xname) {
+		c->xdatum_mem_usage -= (xd->name_len + 1 + xd->value_len);
+		kfree(xd->xname);
+	}
+
+	list_del_init(&xd->xindex);
+	xd->hashkey = 0;
+	xd->xname = NULL;
+	xd->xvalue = NULL;
+}
+
+static void reclaim_xattr_datum(struct jffs2_sb_info *c)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_xattr_datum *xd, *_xd;
+	uint32_t target, before;
+	static int index = 0;
+	int count;
+
+	if (c->xdatum_mem_threshold > c->xdatum_mem_usage)
+		return;
+
+	before = c->xdatum_mem_usage;
+	target = c->xdatum_mem_usage * 4 / 5; /* 20% reduction */
+	for (count = 0; count < XATTRINDEX_HASHSIZE; count++) {
+		list_for_each_entry_safe(xd, _xd, &c->xattrindex[index], xindex) {
+			if (xd->flags & JFFS2_XFLAGS_HOT) {
+				xd->flags &= ~JFFS2_XFLAGS_HOT;
+			} else if (!(xd->flags & JFFS2_XFLAGS_BIND)) {
+				unload_xattr_datum(c, xd);
+			}
+			if (c->xdatum_mem_usage <= target)
+				goto out;
+		}
+		index = (index+1) % XATTRINDEX_HASHSIZE;
+	}
+ out:
+	JFFS2_NOTICE("xdatum_mem_usage from %u byte to %u byte (%u byte reclaimed)\n",
+		     before, c->xdatum_mem_usage, before - c->xdatum_mem_usage);
+}
+
+static void delete_xattr_datum_node(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_raw_xattr rx;
+	uint32_t length;
+	int rc;
+
+	if (!xd->node) {
+		JFFS2_WARNING("xdatum (xid=%u) is removed twice.\n", xd->xid);
+		return;
+	}
+	if (jffs2_sum_active()) {
+		memset(&rx, 0xff, sizeof(struct jffs2_raw_xattr));
+		rc = jffs2_flash_read(c, ref_offset(xd->node),
+				      sizeof(struct jffs2_unknown_node),
+				      &length, (char *)&rx);
+		if (rc || length != sizeof(struct jffs2_unknown_node)) {
+			JFFS2_ERROR("jffs2_flash_read()=%d, req=%u, read=%u at %#08x\n",
+				    rc, sizeof(struct jffs2_unknown_node),
+				    length, ref_offset(xd->node));
+		}
+		rc = jffs2_flash_write(c, ref_offset(xd->node), sizeof(rx),
+				       &length, (char *)&rx);
+		if (rc || length != sizeof(struct jffs2_raw_xattr)) {
+			JFFS2_ERROR("jffs2_flash_write()=%d, req=%u, wrote=%u ar %#08x\n",
+				    rc, sizeof(rx), length, ref_offset(xd->node));
+		}
+	}
+	spin_lock(&c->erase_completion_lock);
+	xd->node->next_in_ino = NULL;
+	spin_unlock(&c->erase_completion_lock);
+	jffs2_mark_node_obsolete(c, xd->node);
+	xd->node = NULL;
+}
+
+static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem) */
+	BUG_ON(xd->refcnt);
+
+	unload_xattr_datum(c, xd);
+	if (xd->node) {
+		delete_xattr_datum_node(c, xd);
+		xd->node = NULL;
+	}
+	jffs2_free_xattr_datum(xd);
+}
+
+static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_eraseblock *jeb;
+	struct jffs2_raw_xattr rx;
+	size_t readlen;
+	uint32_t crc, totlen;
+	int rc;
+
+	BUG_ON(!xd->node);
+	BUG_ON(ref_flags(xd->node) != REF_UNCHECKED);
+
+	rc = jffs2_flash_read(c, ref_offset(xd->node), sizeof(rx), &readlen, (char *)&rx);
+	if (rc || readlen != sizeof(rx)) {
+		JFFS2_WARNING("jffs2_flash_read()=%d, req=%u, read=%u at %#08x\n",
+			      rc, sizeof(rx), readlen, ref_offset(xd->node));
+		return rc ? rc : -EIO;
+	}
+	crc = crc32(0, &rx, sizeof(rx) - 4);
+	if (crc != je32_to_cpu(rx.node_crc)) {
+		if (je32_to_cpu(rx.node_crc) != 0xffffffff)
+			JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+				    ref_offset(xd->node), je32_to_cpu(rx.hdr_crc), crc);
+		return EIO;
+	}
+	totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
+	if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
+	    || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
+	    || je32_to_cpu(rx.totlen) != totlen
+	    || je32_to_cpu(rx.xid) != xd->xid
+	    || je32_to_cpu(rx.version) != xd->version) {
+		JFFS2_ERROR("inconsistent xdatum at %#08x, magic=%#04x/%#04x, "
+			    "nodetype=%#04x/%#04x, totlen=%u/%u, xid=%u/%u, version=%u/%u\n",
+			    ref_offset(xd->node), je16_to_cpu(rx.magic), JFFS2_MAGIC_BITMASK,
+			    je16_to_cpu(rx.nodetype), JFFS2_NODETYPE_XATTR,
+			    je32_to_cpu(rx.totlen), totlen,
+			    je32_to_cpu(rx.xid), xd->xid,
+			    je32_to_cpu(rx.version), xd->version);
+		return EIO;
+	}
+	xd->xprefix = rx.xprefix;
+	xd->name_len = rx.name_len;
+	xd->value_len = je16_to_cpu(rx.value_len);
+	xd->data_crc = je32_to_cpu(rx.data_crc);
+
+	/* This JFFS2_NODETYPE_XATTR node is checked */
+	jeb = &c->blocks[ref_offset(xd->node) / c->sector_size];
+	totlen = PAD(je32_to_cpu(rx.totlen));
+
+	spin_lock(&c->erase_completion_lock);
+	c->unchecked_size -= totlen; c->used_size += totlen;
+	jeb->unchecked_size -= totlen; jeb->used_size += totlen;
+	xd->node->flash_offset = ref_offset(xd->node) | REF_PRISTINE;
+	spin_unlock(&c->erase_completion_lock);
+
+	/* unchecked xdatum is chained with c->xattr_unchecked */
+	list_del_init(&xd->xindex);
+
+	dbg_xattr("success on verfying xdatum (xid=%u, version=%u)\n",
+		  xd->xid, xd->version);
+
+	return 0;
+}
+
+static int do_load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem) */
+	char *data;
+	size_t readlen;
+	uint32_t crc, length;
+	int i, ret, retry = 0;
+
+	BUG_ON(!xd->node);
+	BUG_ON(ref_flags(xd->node) != REF_PRISTINE);
+	BUG_ON(!list_empty(&xd->xindex));
+ retry:
+	length = xd->name_len + 1 + xd->value_len;
+	data = kmalloc(length, GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	ret = jffs2_flash_read(c, ref_offset(xd->node)+sizeof(struct jffs2_raw_xattr),
+			       length, &readlen, data);
+
+	if (ret || length!=readlen) {
+		JFFS2_WARNING("jffs2_flash_read() returned %d, request=%d, readlen=%d, at %#08x\n",
+			      ret, length, readlen, ref_offset(xd->node));
+		kfree(data);
+		return ret ? ret : -EIO;
+	}
+
+	data[xd->name_len] = '\0';
+	crc = crc32(0, data, length);
+	if (crc != xd->data_crc) {
+		JFFS2_WARNING("node CRC failed (JFFS2_NODETYPE_XREF)"
+			      " at %#08x, read: 0x%08x calculated: 0x%08x\n",
+			      ref_offset(xd->node), xd->data_crc, crc);
+		kfree(data);
+		return EIO;
+	}
+
+	xd->flags |= JFFS2_XFLAGS_HOT;
+	xd->xname = data;
+	xd->xvalue = data + xd->name_len+1;
+
+	c->xdatum_mem_usage += length;
+
+	xd->hashkey = xattr_datum_hashkey(xd->xprefix, xd->xname, xd->xvalue, xd->value_len);
+	i = xd->hashkey % XATTRINDEX_HASHSIZE;
+	list_add(&xd->xindex, &c->xattrindex[i]);
+	if (!retry) {
+		retry = 1;
+		reclaim_xattr_datum(c);
+		if (!xd->xname)
+			goto retry;
+	}
+
+	dbg_xattr("success on loading xdatum (xid=%u, xprefix=%u, xname='%s')\n",
+		  xd->xid, xd->xprefix, xd->xname);
+
+	return 0;
+}
+
+static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	/* must be called under down_write(xattr_sem);
+	 * rc < 0 : recoverable error, try again
+	 * rc = 0 : success
+	 * rc > 0 : Unrecoverable error, this node should be deleted.
+	 */
+	int rc = 0;
+	BUG_ON(xd->xname);
+	if (!xd->node)
+		return EIO;
+	if (unlikely(ref_flags(xd->node) != REF_PRISTINE)) {
+		rc = do_verify_xattr_datum(c, xd);
+		if (rc > 0) {
+			list_del_init(&xd->xindex);
+			delete_xattr_datum_node(c, xd);
+		}
+	}
+	if (!rc)
+		rc = do_load_xattr_datum(c, xd);
+	return rc;
+}
+
+static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd, uint32_t phys_ofs)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_raw_xattr rx;
+	struct jffs2_raw_node_ref *raw;
+	struct kvec vecs[2];
+	uint32_t length;
+	int rc, totlen;
+
+	BUG_ON(!xd->xname);
+
+	vecs[0].iov_base = &rx;
+	vecs[0].iov_len = PAD(sizeof(rx));
+	vecs[1].iov_base = xd->xname;
+	vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
+	totlen = vecs[0].iov_len + vecs[1].iov_len;
+
+	raw = jffs2_alloc_raw_node_ref();
+	if (!raw)
+		return -ENOMEM;
+	raw->flash_offset = phys_ofs;
+	raw->__totlen = PAD(totlen);
+	raw->next_phys = NULL;
+	raw->next_in_ino = (void *)xd;
+
+	/* Setup raw-xattr */
+	rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	rx.nodetype = cpu_to_je16(JFFS2_NODETYPE_XATTR);
+	rx.totlen = cpu_to_je32(PAD(totlen));
+	rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
+
+	rx.xid = cpu_to_je32(xd->xid);
+	rx.version = cpu_to_je32(++xd->version);
+	rx.xprefix = xd->xprefix;
+	rx.name_len = xd->name_len;
+	rx.value_len = cpu_to_je16(xd->value_len);
+	rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
+	rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
+
+	rc = jffs2_flash_writev(c, vecs, 2, phys_ofs, &length, 0);
+	if (rc || totlen != length) {
+		JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%u, at %#08x\n",
+			      rc, totlen, length, phys_ofs);
+		rc = rc ? rc : -EIO;
+		if (length) {
+			raw->flash_offset |= REF_OBSOLETE;
+			raw->next_in_ino = NULL;
+			jffs2_add_physical_node_ref(c, raw);
+			jffs2_mark_node_obsolete(c, raw);
+		} else {
+			jffs2_free_raw_node_ref(raw);
+		}
+		return rc;
+	}
+	BUG_ON(raw->__totlen < sizeof(struct jffs2_raw_xattr));
+	/* success */
+	raw->flash_offset |= REF_PRISTINE;
+	jffs2_add_physical_node_ref(c, raw);
+	if (xd->node)
+		delete_xattr_datum_node(c, xd);
+	xd->node = raw;
+
+	dbg_xattr("success on saving xdatum (xid=%u, version=%u, xprefix=%u, xname='%s')\n",
+		  xd->xid, xd->version, xd->xprefix, xd->xname);
+
+	return 0;
+}
+
+static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
+						    int xprefix, const char *xname,
+						    const char *xvalue, int xsize,
+						    uint32_t phys_ofs)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_xattr_datum *xd;
+	uint32_t hashkey, name_len;
+	char *data;
+	int i, rc;
+
+	/* Search xattr_datum has same xname/xvalue by index */
+	hashkey = xattr_datum_hashkey(xprefix, xname, xvalue, xsize);
+	i = hashkey % XATTRINDEX_HASHSIZE;
+	list_for_each_entry(xd, &c->xattrindex[i], xindex) {
+		if (xd->hashkey==hashkey
+		    && xd->xprefix==xprefix
+		    && xd->value_len==xsize
+		    && !strcmp(xd->xname, xname)
+		    && !memcmp(xd->xvalue, xvalue, xsize)) {
+			xd->refcnt++;
+			return xd;
+		}
+	}
+
+	/* Not found, Create NEW XATTR-Cache */
+	name_len = strlen(xname);
+
+	xd = jffs2_alloc_xattr_datum();
+	if (!xd)
+		return ERR_PTR(-ENOMEM);
+
+	data = kmalloc(name_len + 1 + xsize, GFP_KERNEL);
+	if (!data) {
+		jffs2_free_xattr_datum(xd);
+		return ERR_PTR(-ENOMEM);
+	}
+	strcpy(data, xname);
+	memcpy(data + name_len + 1, xvalue, xsize);
+
+	xd->refcnt = 1;
+	xd->xid = ++c->highest_xid;
+	xd->flags |= JFFS2_XFLAGS_HOT;
+	xd->xprefix = xprefix;
+
+	xd->hashkey = hashkey;
+	xd->xname = data;
+	xd->xvalue = data + name_len + 1;
+	xd->name_len = name_len;
+	xd->value_len = xsize;
+	xd->data_crc = crc32(0, data, xd->name_len + 1 + xd->value_len);
+
+	rc = save_xattr_datum(c, xd, phys_ofs);
+	if (rc) {
+		kfree(xd->xname);
+		jffs2_free_xattr_datum(xd);
+		return ERR_PTR(rc);
+	}
+
+	/* Insert Hash Index */
+	i = hashkey % XATTRINDEX_HASHSIZE;
+	list_add(&xd->xindex, &c->xattrindex[i]);
+
+	c->xdatum_mem_usage += (xd->name_len + 1 + xd->value_len);
+	reclaim_xattr_datum(c);
+
+	return xd;
+}
+
+/* -------- xref related functions ------------------
+ * verify_xattr_ref(c, ref)
+ *   is used to load xref information from medium. Because summary data does not
+ *   contain xid/ino, it's necessary to verify once while mounting process.
+ * delete_xattr_ref_node(c, ref)
+ *   is used to delete a jffs2 node is dominated by xref. When EBS is enabled,
+ *   it overwrites the obsolete node by myself. 
+ * delete_xattr_ref(c, ref)
+ *   is used to delete jffs2_xattr_ref object. If the reference counter of xdatum
+ *   is refered by this xref become 0, delete_xattr_datum() is called later.
+ * save_xattr_ref(c, ref, phys_ofs)
+ *   is used to write xref to medium.
+ * create_xattr_ref(c, ic, xd, phys_ofs)
+ *   is used to create a new xref and write to medium.
+ * jffs2_xattr_delete_inode(c, ic)
+ *   is called to remove xrefs related to obsolete inode when inode is unlinked.
+ * jffs2_xattr_free_inode(c, ic)
+ *   is called to release xattr related objects when unmounting. 
+ * check_xattr_ref_inode(c, ic)
+ *   is used to confirm inode does not have duplicate xattr name/value pair.
+ * -------------------------------------------------- */
+static int verify_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+	struct jffs2_eraseblock *jeb;
+	struct jffs2_raw_xref rr;
+	size_t readlen;
+	uint32_t crc, totlen;
+	int rc;
+
+	BUG_ON(ref_flags(ref->node) != REF_UNCHECKED);
+
+	rc = jffs2_flash_read(c, ref_offset(ref->node), sizeof(rr), &readlen, (char *)&rr);
+	if (rc || sizeof(rr) != readlen) {
+		JFFS2_WARNING("jffs2_flash_read()=%d, req=%u, read=%u, at %#08x\n",
+			      rc, sizeof(rr), readlen, ref_offset(ref->node));
+		return rc ? rc : -EIO;
+	}
+	/* obsolete node */
+	crc = crc32(0, &rr, sizeof(rr) - 4);
+	if (crc != je32_to_cpu(rr.node_crc)) {
+		if (je32_to_cpu(rr.node_crc) != 0xffffffff)
+			JFFS2_ERROR("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
+				    ref_offset(ref->node), je32_to_cpu(rr.node_crc), crc);
+		return EIO;
+	}
+	if (je16_to_cpu(rr.magic) != JFFS2_MAGIC_BITMASK
+	    || je16_to_cpu(rr.nodetype) != JFFS2_NODETYPE_XREF
+	    || je32_to_cpu(rr.totlen) != PAD(sizeof(rr))) {
+		JFFS2_ERROR("inconsistent xref at %#08x, magic=%#04x/%#04x, "
+			    "nodetype=%#04x/%#04x, totlen=%u/%u\n",
+			    ref_offset(ref->node), je16_to_cpu(rr.magic), JFFS2_MAGIC_BITMASK,
+			    je16_to_cpu(rr.nodetype), JFFS2_NODETYPE_XREF,
+			    je32_to_cpu(rr.totlen), PAD(sizeof(rr)));
+		return EIO;
+	}
+	ref->ino = je32_to_cpu(rr.ino);
+	ref->xid = je32_to_cpu(rr.xid);
+
+	/* fixup superblock/eraseblock info */
+	jeb = &c->blocks[ref_offset(ref->node) / c->sector_size];
+	totlen = PAD(sizeof(rr));
+
+	spin_lock(&c->erase_completion_lock);
+	c->unchecked_size -= totlen; c->used_size += totlen;
+	jeb->unchecked_size -= totlen; jeb->used_size += totlen;
+	ref->node->flash_offset = ref_offset(ref->node) | REF_PRISTINE;
+	spin_unlock(&c->erase_completion_lock);
+
+	dbg_xattr("success on verifying xref (ino=%u, xid=%u) at %#08x\n",
+		  ref->ino, ref->xid, ref_offset(ref->node));
+	return 0;
+}
+
+static void delete_xattr_ref_node(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+	struct jffs2_raw_xref rr;
+	uint32_t length;
+	int rc;
+
+	if (jffs2_sum_active()) {
+		memset(&rr, 0xff, sizeof(rr));
+		rc = jffs2_flash_read(c, ref_offset(ref->node),
+				      sizeof(struct jffs2_unknown_node),
+				      &length, (char *)&rr);
+		if (rc || length != sizeof(struct jffs2_unknown_node)) {
+			JFFS2_ERROR("jffs2_flash_read()=%d, req=%u, read=%u at %#08x\n",
+				    rc, sizeof(struct jffs2_unknown_node),
+				    length, ref_offset(ref->node));
+		}
+		rc = jffs2_flash_write(c, ref_offset(ref->node), sizeof(rr),
+				       &length, (char *)&rr);
+		if (rc || length != sizeof(struct jffs2_raw_xref)) {
+			JFFS2_ERROR("jffs2_flash_write()=%d, req=%u, wrote=%u at %#08x\n",
+				    rc, sizeof(rr), length, ref_offset(ref->node));
+		}
+	}
+	spin_lock(&c->erase_completion_lock);
+	ref->node->next_in_ino = NULL;
+	spin_unlock(&c->erase_completion_lock);
+	jffs2_mark_node_obsolete(c, ref->node);
+	ref->node = NULL;
+}
+
+static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_xattr_datum *xd;
+
+	BUG_ON(!ref->node);
+	delete_xattr_ref_node(c, ref);
+
+	xd = ref->xd;
+	xd->refcnt--;
+	if (!xd->refcnt)
+		delete_xattr_datum(c, xd);
+	jffs2_free_xattr_ref(ref);
+}
+
+static int save_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref, uint32_t phys_ofs)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_raw_node_ref *raw;
+	struct jffs2_raw_xref rr;
+	uint32_t length;
+	int ret;
+
+	raw = jffs2_alloc_raw_node_ref();
+	if (!raw)
+		return -ENOMEM;
+	raw->flash_offset = phys_ofs;
+	raw->__totlen = PAD(sizeof(rr));
+	raw->next_phys = NULL;
+	raw->next_in_ino = (void *)ref;
+
+	rr.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
+	rr.nodetype = cpu_to_je16(JFFS2_NODETYPE_XREF);
+	rr.totlen = cpu_to_je32(PAD(sizeof(rr)));
+	rr.hdr_crc = cpu_to_je32(crc32(0, &rr, sizeof(struct jffs2_unknown_node) - 4));
+
+	rr.ino = cpu_to_je32(ref->ic->ino);
+	rr.xid = cpu_to_je32(ref->xd->xid);
+	rr.node_crc = cpu_to_je32(crc32(0, &rr, sizeof(rr) - 4));
+
+	ret = jffs2_flash_write(c, phys_ofs, sizeof(rr), &length, (char *)&rr);
+	if (ret || sizeof(rr) != length) {
+		JFFS2_WARNING("jffs2_flash_write() returned %d, request=%u, retlen=%u, at %#08x\n",
+			      ret, sizeof(rr), length, phys_ofs);
+		ret = ret ? ret : -EIO;
+		if (length) {
+			raw->flash_offset |= REF_OBSOLETE;
+			raw->next_in_ino = NULL;
+			jffs2_add_physical_node_ref(c, raw);
+			jffs2_mark_node_obsolete(c, raw);
+		} else {
+			jffs2_free_raw_node_ref(raw);
+		}
+		return ret;
+	}
+	raw->flash_offset |= REF_PRISTINE;
+
+	jffs2_add_physical_node_ref(c, raw);
+	if (ref->node)
+		delete_xattr_ref_node(c, ref);
+	ref->node = raw;
+
+	dbg_xattr("success on saving xref (ino=%u, xid=%u)\n", ref->ic->ino, ref->xd->xid);
+
+	return 0;
+}
+
+static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic,
+						struct jffs2_xattr_datum *xd, uint32_t phys_ofs)
+{
+	/* must be called under down_write(xattr_sem) */
+	struct jffs2_xattr_ref *ref;
+	int ret;
+
+	ref = jffs2_alloc_xattr_ref();
+	if (!ref)
+		return ERR_PTR(-ENOMEM);
+	ref->ic = ic;
+	ref->xd = xd;
+
+	ret = save_xattr_ref(c, ref, phys_ofs);
+	if (ret) {
+		jffs2_free_xattr_ref(ref);
+		return ERR_PTR(ret);
+	}
+
+	/* Chain to inode */
+	ref->next = ic->xref;
+	ic->xref = ref;
+
+	return ref; /* success */
+}
+
+void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+	/* It's called from jffs2_clear_inode() on inode removing.
+	   When an inode with XATTR is removed, those XATTRs must be removed. */
+	struct jffs2_xattr_ref *ref, *_ref;
+
+	if (!ic || ic->nlink > 0)
+		return;
+
+	down_write(&c->xattr_sem);
+	for (ref = ic->xref; ref; ref = _ref) {
+		_ref = ref->next;
+		delete_xattr_ref(c, ref);
+	}
+	ic->xref = NULL;
+	up_write(&c->xattr_sem);
+}
+
+void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+	/* It's called from jffs2_free_ino_caches() until unmounting FS. */
+	struct jffs2_xattr_datum *xd;
+	struct jffs2_xattr_ref *ref, *_ref;
+
+	down_write(&c->xattr_sem);
+	for (ref = ic->xref; ref; ref = _ref) {
+		_ref = ref->next;
+		xd = ref->xd;
+		xd->refcnt--;
+		if (!xd->refcnt) {
+			unload_xattr_datum(c, xd);
+			jffs2_free_xattr_datum(xd);
+		}
+		jffs2_free_xattr_ref(ref);
+	}
+	ic->xref = NULL;
+	up_write(&c->xattr_sem);
+}
+
+static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
+{
+	/* success of check_xattr_ref_inode() means taht inode (ic) dose not have
+	 * duplicate name/value pairs. If duplicate name/value pair would be found,
+	 * one will be removed.
+	 */
+	struct jffs2_xattr_ref *ref, *cmp, **pref;
+	int rc = 0;
+
+	if (likely(ic->flags & INO_FLAGS_XATTR_CHECKED))
+		return 0;
+	down_write(&c->xattr_sem);
+ retry:
+	rc = 0;
+	for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
+		if (!ref->xd->xname) {
+			rc = load_xattr_datum(c, ref->xd);
+			if (unlikely(rc > 0)) {
+				*pref = ref->next;
+				delete_xattr_ref(c, ref);
+				goto retry;
+			} else if (unlikely(rc < 0))
+				goto out;
+		}
+		for (cmp=ref->next, pref=&ref->next; cmp; pref=&cmp->next, cmp=cmp->next) {
+			if (!cmp->xd->xname) {
+				ref->xd->flags |= JFFS2_XFLAGS_BIND;
+				rc = load_xattr_datum(c, cmp->xd);
+				ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
+				if (unlikely(rc > 0)) {
+					*pref = cmp->next;
+					delete_xattr_ref(c, cmp);
+					goto retry;
+				} else if (unlikely(rc < 0))
+					goto out;
+			}
+			if (ref->xd->xprefix == cmp->xd->xprefix
+			    && !strcmp(ref->xd->xname, cmp->xd->xname)) {
+				*pref = cmp->next;
+				delete_xattr_ref(c, cmp);
+				goto retry;
+			}
+		}
+	}
+	ic->flags |= INO_FLAGS_XATTR_CHECKED;
+ out:
+	up_write(&c->xattr_sem);
+
+	return rc;
+}
+
+/* -------- xattr subsystem functions ---------------
+ * jffs2_init_xattr_subsystem(c)
+ *   is used to initialize semaphore and list_head, and some variables.
+ * jffs2_find_xattr_datum(c, xid)
+ *   is used to lookup xdatum while scanning process.
+ * jffs2_clear_xattr_subsystem(c)
+ *   is used to release any xattr related objects.
+ * jffs2_build_xattr_subsystem(c)
+ *   is used to associate xdatum and xref while super block building process.
+ * jffs2_setup_xattr_datum(c, xid, version)
+ *   is used to insert xdatum while scanning process.
+ * -------------------------------------------------- */
+void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c)
+{
+	int i;
+
+	for (i=0; i < XATTRINDEX_HASHSIZE; i++)
+		INIT_LIST_HEAD(&c->xattrindex[i]);
+	INIT_LIST_HEAD(&c->xattr_unchecked);
+	c->xref_temp = NULL;
+
+	init_rwsem(&c->xattr_sem);
+	c->xdatum_mem_usage = 0;
+	c->xdatum_mem_threshold = 32 * 1024;	/* Default 32KB */
+}
+
+static struct jffs2_xattr_datum *jffs2_find_xattr_datum(struct jffs2_sb_info *c, uint32_t xid)
+{
+	struct jffs2_xattr_datum *xd;
+	int i = xid % XATTRINDEX_HASHSIZE;
+
+	/* It's only used in scanning/building process. */
+	BUG_ON(!(c->flags & (JFFS2_SB_FLAG_SCANNING|JFFS2_SB_FLAG_BUILDING)));
+
+	list_for_each_entry(xd, &c->xattrindex[i], xindex) {
+		if (xd->xid==xid)
+			return xd;
+	}
+	return NULL;
+}
+
+void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c)
+{
+	struct jffs2_xattr_datum *xd, *_xd;
+	struct jffs2_xattr_ref *ref, *_ref;
+	int i;
+
+	for (ref=c->xref_temp; ref; ref = _ref) {
+		_ref = ref->next;
+		jffs2_free_xattr_ref(ref);
+	}
+	c->xref_temp = NULL;
+
+	for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
+		list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
+			list_del(&xd->xindex);
+			if (xd->xname)
+				kfree(xd->xname);
+			jffs2_free_xattr_datum(xd);
+		}
+	}
+}
+
+void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
+{
+	struct jffs2_xattr_ref *ref, *_ref;
+	struct jffs2_xattr_datum *xd, *_xd;
+	struct jffs2_inode_cache *ic;
+	int i, xdatum_count =0, xdatum_unchecked_count = 0, xref_count = 0;
+
+	BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
+
+	/* Phase.1 */
+	for (ref=c->xref_temp; ref; ref=_ref) {
+		_ref = ref->next;
+		/* checking REF_UNCHECKED nodes */
+		if (ref_flags(ref->node) != REF_PRISTINE) {
+			if (verify_xattr_ref(c, ref)) {
+				delete_xattr_ref_node(c, ref);
+				jffs2_free_xattr_ref(ref);
+				continue;
+			}
+		}
+		/* At this point, ref->xid and ref->ino contain XID and inode number.
+		   ref->xd and ref->ic are not valid yet. */
+		xd = jffs2_find_xattr_datum(c, ref->xid);
+		ic = jffs2_get_ino_cache(c, ref->ino);
+		if (!xd || !ic) {
+			if (ref_flags(ref->node) != REF_UNCHECKED)
+				JFFS2_WARNING("xref(ino=%u, xid=%u) is orphan. \n",
+					      ref->ino, ref->xid);
+			delete_xattr_ref_node(c, ref);
+			jffs2_free_xattr_ref(ref);
+			continue;
+		}
+		ref->xd = xd;
+		ref->ic = ic;
+		xd->refcnt++;
+		ref->next = ic->xref;
+		ic->xref = ref;
+		xref_count++;
+	}
+	c->xref_temp = NULL;
+	/* After this, ref->xid/ino are NEVER used. */
+
+	/* Phase.2 */
+	for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
+		list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
+			list_del_init(&xd->xindex);
+			if (!xd->refcnt) {
+				if (ref_flags(xd->node) != REF_UNCHECKED)
+					JFFS2_WARNING("orphan xdatum(xid=%u, version=%u) at %#08x\n",
+						      xd->xid, xd->version, ref_offset(xd->node));
+				delete_xattr_datum(c, xd);
+				continue;
+			}
+			if (ref_flags(xd->node) != REF_PRISTINE) {
+				dbg_xattr("unchecked xdatum(xid=%u) at %#08x\n",
+					  xd->xid, ref_offset(xd->node));
+				list_add(&xd->xindex, &c->xattr_unchecked);
+				xdatum_unchecked_count++;
+			}
+			xdatum_count++;
+		}
+	}
+	/* build complete */
+	JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum (%u unchecked) and "
+		     "%u of xref found.\n", xdatum_count, xdatum_unchecked_count, xref_count);
+}
+
+struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
+						  uint32_t xid, uint32_t version)
+{
+	struct jffs2_xattr_datum *xd, *_xd;
+
+	_xd = jffs2_find_xattr_datum(c, xid);
+	if (_xd) {
+		dbg_xattr("duplicate xdatum (xid=%u, version=%u/%u) at %#08x\n",
+			  xid, version, _xd->version, ref_offset(_xd->node));
+		if (version < _xd->version)
+			return ERR_PTR(-EEXIST);
+	}
+	xd = jffs2_alloc_xattr_datum();
+	if (!xd)
+		return ERR_PTR(-ENOMEM);
+	xd->xid = xid;
+	xd->version = version;
+	if (xd->xid > c->highest_xid)
+		c->highest_xid = xd->xid;
+	list_add_tail(&xd->xindex, &c->xattrindex[xid % XATTRINDEX_HASHSIZE]);
+
+	if (_xd) {
+		list_del_init(&_xd->xindex);
+		delete_xattr_datum_node(c, _xd);
+		jffs2_free_xattr_datum(_xd);
+	}
+	return xd;
+}
+
+/* -------- xattr subsystem functions ---------------
+ * xprefix_to_handler(xprefix)
+ *   is used to translate xprefix into xattr_handler.
+ * jffs2_listxattr(dentry, buffer, size)
+ *   is an implementation of listxattr handler on jffs2.
+ * do_jffs2_getxattr(inode, xprefix, xname, buffer, size)
+ *   is an implementation of getxattr handler on jffs2.
+ * do_jffs2_setxattr(inode, xprefix, xname, buffer, size, flags)
+ *   is an implementation of setxattr handler on jffs2.
+ * -------------------------------------------------- */
+struct xattr_handler *jffs2_xattr_handlers[] = {
+	&jffs2_user_xattr_handler,
+#ifdef CONFIG_JFFS2_FS_SECURITY
+	&jffs2_security_xattr_handler,
+#endif
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+	&jffs2_acl_access_xattr_handler,
+	&jffs2_acl_default_xattr_handler,
+#endif
+	&jffs2_trusted_xattr_handler,
+	NULL
+};
+
+static struct xattr_handler *xprefix_to_handler(int xprefix) {
+	struct xattr_handler *ret;
+
+	switch (xprefix) {
+	case JFFS2_XPREFIX_USER:
+		ret = &jffs2_user_xattr_handler;
+		break;
+#ifdef CONFIG_JFFS2_FS_SECURITY
+	case JFFS2_XPREFIX_SECURITY:
+		ret = &jffs2_security_xattr_handler;
+		break;
+#endif
+#ifdef CONFIG_JFFS2_FS_POSIX_ACL
+	case JFFS2_XPREFIX_ACL_ACCESS:
+		ret = &jffs2_acl_access_xattr_handler;
+		break;
+	case JFFS2_XPREFIX_ACL_DEFAULT:
+		ret = &jffs2_acl_default_xattr_handler;
+		break;
+#endif
+	case JFFS2_XPREFIX_TRUSTED:
+		ret = &jffs2_trusted_xattr_handler;
+		break;
+	default:
+		ret = NULL;
+		break;
+	}
+	return ret;
+}
+
+ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_inode_cache *ic = f->inocache;
+	struct jffs2_xattr_ref *ref, **pref;
+	struct jffs2_xattr_datum *xd;
+	struct xattr_handler *xhandle;
+	ssize_t len, rc;
+	int retry = 0;
+
+	rc = check_xattr_ref_inode(c, ic);
+	if (unlikely(rc))
+		return rc;
+
+	down_read(&c->xattr_sem);
+ retry:
+	len = 0;
+	for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
+		BUG_ON(ref->ic != ic);
+		xd = ref->xd;
+		if (!xd->xname) {
+			/* xdatum is unchached */
+			if (!retry) {
+				retry = 1;
+				up_read(&c->xattr_sem);
+				down_write(&c->xattr_sem);
+				goto retry;
+			} else {
+				rc = load_xattr_datum(c, xd);
+				if (unlikely(rc > 0)) {
+					*pref = ref->next;
+					delete_xattr_ref(c, ref);
+					goto retry;
+				} else if (unlikely(rc < 0))
+					goto out;
+			}
+		}
+		xhandle = xprefix_to_handler(xd->xprefix);
+		if (!xhandle)
+			continue;
+		if (buffer) {
+			rc = xhandle->list(inode, buffer+len, size-len, xd->xname, xd->name_len);
+		} else {
+			rc = xhandle->list(inode, NULL, 0, xd->xname, xd->name_len);
+		}
+		if (rc < 0)
+			goto out;
+		len += rc;
+	}
+	rc = len;
+ out:
+	if (!retry) {
+		up_read(&c->xattr_sem);
+	} else {
+		up_write(&c->xattr_sem);
+	}
+	return rc;
+}
+
+int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
+		      char *buffer, size_t size)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_inode_cache *ic = f->inocache;
+	struct jffs2_xattr_datum *xd;
+	struct jffs2_xattr_ref *ref, **pref;
+	int rc, retry = 0;
+
+	rc = check_xattr_ref_inode(c, ic);
+	if (unlikely(rc))
+		return rc;
+
+	down_read(&c->xattr_sem);
+ retry:
+	for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
+		BUG_ON(ref->ic!=ic);
+
+		xd = ref->xd;
+		if (xd->xprefix != xprefix)
+			continue;
+		if (!xd->xname) {
+			/* xdatum is unchached */
+			if (!retry) {
+				retry = 1;
+				up_read(&c->xattr_sem);
+				down_write(&c->xattr_sem);
+				goto retry;
+			} else {
+				rc = load_xattr_datum(c, xd);
+				if (unlikely(rc > 0)) {
+					*pref = ref->next;
+					delete_xattr_ref(c, ref);
+					goto retry;
+				} else if (unlikely(rc < 0)) {
+					goto out;
+				}
+			}
+		}
+		if (!strcmp(xname, xd->xname)) {
+			rc = xd->value_len;
+			if (buffer) {
+				if (size < rc) {
+					rc = -ERANGE;
+				} else {
+					memcpy(buffer, xd->xvalue, rc);
+				}
+			}
+			goto out;
+		}
+	}
+	rc = -ENODATA;
+ out:
+	if (!retry) {
+		up_read(&c->xattr_sem);
+	} else {
+		up_write(&c->xattr_sem);
+	}
+	return rc;
+}
+
+int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
+		      const char *buffer, size_t size, int flags)
+{
+	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
+	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
+	struct jffs2_inode_cache *ic = f->inocache;
+	struct jffs2_xattr_datum *xd;
+	struct jffs2_xattr_ref *ref, *newref, **pref;
+	uint32_t phys_ofs, length, request;
+	int rc;
+
+	rc = check_xattr_ref_inode(c, ic);
+	if (unlikely(rc))
+		return rc;
+
+	request = PAD(sizeof(struct jffs2_raw_xattr) + strlen(xname) + 1 + size);
+	rc = jffs2_reserve_space(c, request, &phys_ofs, &length,
+				 ALLOC_NORMAL, JFFS2_SUMMARY_XATTR_SIZE);
+	if (rc) {
+		JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
+		return rc;
+	}
+
+	/* Find existing xattr */
+	down_write(&c->xattr_sem);
+ retry:
+	for (ref=ic->xref, pref=&ic->xref; ref; pref=&ref->next, ref=ref->next) {
+		xd = ref->xd;
+		if (xd->xprefix != xprefix)
+			continue;
+		if (!xd->xname) {
+			rc = load_xattr_datum(c, xd);
+			if (unlikely(rc > 0)) {
+				*pref = ref->next;
+				delete_xattr_ref(c, ref);
+				goto retry;
+			} else if (unlikely(rc < 0))
+				goto out;
+		}
+		if (!strcmp(xd->xname, xname)) {
+			if (flags & XATTR_CREATE) {
+				rc = -EEXIST;
+				goto out;
+			}
+			if (!buffer) {
+				*pref = ref->next;
+				delete_xattr_ref(c, ref);
+				rc = 0;
+				goto out;
+			}
+			goto found;
+		}
+	}
+	/* not found */
+	if (flags & XATTR_REPLACE) {
+		rc = -ENODATA;
+		goto out;
+	}
+	if (!buffer) {
+		rc = -EINVAL;
+		goto out;
+	}
+ found:
+	xd = create_xattr_datum(c, xprefix, xname, buffer, size, phys_ofs);
+	if (IS_ERR(xd)) {
+		rc = PTR_ERR(xd);
+		goto out;
+	}
+	up_write(&c->xattr_sem);
+	jffs2_complete_reservation(c);
+
+	/* create xattr_ref */
+	request = PAD(sizeof(struct jffs2_raw_xref));
+	rc = jffs2_reserve_space(c, request, &phys_ofs, &length,
+				 ALLOC_NORMAL, JFFS2_SUMMARY_XREF_SIZE);
+	if (rc) {
+		JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
+		down_write(&c->xattr_sem);
+		xd->refcnt--;
+		if (!xd->refcnt)
+			delete_xattr_datum(c, xd);
+		up_write(&c->xattr_sem);
+		return rc;
+	}
+	down_write(&c->xattr_sem);
+	if (ref)
+		*pref = ref->next;
+	newref = create_xattr_ref(c, ic, xd, phys_ofs);
+	if (IS_ERR(newref)) {
+		if (ref) {
+			ref->next = ic->xref;
+			ic->xref = ref;
+		}
+		rc = PTR_ERR(newref);
+		xd->refcnt--;
+		if (!xd->refcnt)
+			delete_xattr_datum(c, xd);
+	} else if (ref) {
+		delete_xattr_ref(c, ref);
+	}
+ out:
+	up_write(&c->xattr_sem);
+	jffs2_complete_reservation(c);
+	return rc;
+}
+
+/* -------- garbage collector functions -------------
+ * jffs2_garbage_collect_xattr_datum(c, xd)
+ *   is used to move xdatum into new node.
+ * jffs2_garbage_collect_xattr_ref(c, ref)
+ *   is used to move xref into new node.
+ * jffs2_verify_xattr(c)
+ *   is used to call do_verify_xattr_datum() before garbage collecting.
+ * -------------------------------------------------- */
+int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+{
+	uint32_t phys_ofs, totlen, length, old_ofs;
+	int rc = -EINVAL;
+
+	down_write(&c->xattr_sem);
+	BUG_ON(!xd->node);
+
+	old_ofs = ref_offset(xd->node);
+	totlen = ref_totlen(c, c->gcblock, xd->node);
+	if (totlen < sizeof(struct jffs2_raw_xattr))
+		goto out;
+
+	if (!xd->xname) {
+		rc = load_xattr_datum(c, xd);
+		if (unlikely(rc > 0)) {
+			delete_xattr_datum_node(c, xd);
+			rc = 0;
+			goto out;
+		} else if (unlikely(rc < 0))
+			goto out;
+	}
+	rc = jffs2_reserve_space_gc(c, totlen, &phys_ofs, &length, JFFS2_SUMMARY_XATTR_SIZE);
+	if (rc || length < totlen) {
+		JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, totlen);
+		rc = rc ? rc : -EBADFD;
+		goto out;
+	}
+	rc = save_xattr_datum(c, xd, phys_ofs);
+	if (!rc)
+		dbg_xattr("xdatum (xid=%u, version=%u) GC'ed from %#08x to %08x\n",
+			  xd->xid, xd->version, old_ofs, ref_offset(xd->node));
+ out:
+	up_write(&c->xattr_sem);
+	return rc;
+}
+
+
+int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+{
+	uint32_t phys_ofs, totlen, length, old_ofs;
+	int rc = -EINVAL;
+
+	down_write(&c->xattr_sem);
+	BUG_ON(!ref->node);
+
+	old_ofs = ref_offset(ref->node);
+	totlen = ref_totlen(c, c->gcblock, ref->node);
+	if (totlen != sizeof(struct jffs2_raw_xref))
+		goto out;
+
+	rc = jffs2_reserve_space_gc(c, totlen, &phys_ofs, &length, JFFS2_SUMMARY_XREF_SIZE);
+	if (rc || length < totlen) {
+		JFFS2_WARNING("%s: jffs2_reserve_space() = %d, request = %u\n",
+			      __FUNCTION__, rc, totlen);
+		rc = rc ? rc : -EBADFD;
+		goto out;
+	}
+	rc = save_xattr_ref(c, ref, phys_ofs);
+	if (!rc)
+		dbg_xattr("xref (ino=%u, xid=%u) GC'ed from %#08x to %08x\n",
+			  ref->ic->ino, ref->xd->xid, old_ofs, ref_offset(ref->node));
+ out:
+	up_write(&c->xattr_sem);
+	return rc;
+}
+
+int jffs2_verify_xattr(struct jffs2_sb_info *c)
+{
+	struct jffs2_xattr_datum *xd, *_xd;
+	int rc;
+
+	down_write(&c->xattr_sem);
+	list_for_each_entry_safe(xd, _xd, &c->xattr_unchecked, xindex) {
+		rc = do_verify_xattr_datum(c, xd);
+		if (rc == 0) {
+			list_del_init(&xd->xindex);
+			break;
+		} else if (rc > 0) {
+			list_del_init(&xd->xindex);
+			delete_xattr_datum_node(c, xd);
+		}
+	}
+	up_write(&c->xattr_sem);
+
+	return list_empty(&c->xattr_unchecked) ? 1 : 0;
+}

fs/jffs2/xattr.h

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#ifndef _JFFS2_FS_XATTR_H_
+#define _JFFS2_FS_XATTR_H_
+
+#include <linux/xattr.h>
+#include <linux/list.h>
+
+#define JFFS2_XFLAGS_HOT	(0x01)	/* This datum is HOT */
+#define JFFS2_XFLAGS_BIND	(0x02)	/* This datum is not reclaimed */
+
+struct jffs2_xattr_datum
+{
+	void *always_null;
+	u8 class;
+	u8 flags;
+	u16 xprefix;			/* see JFFS2_XATTR_PREFIX_* */
+
+	struct jffs2_raw_node_ref *node;
+	struct list_head xindex;	/* chained from c->xattrindex[n] */
+	uint32_t refcnt;		/* # of xattr_ref refers this */
+	uint32_t xid;
+	uint32_t version;
+
+	uint32_t data_crc;
+	uint32_t hashkey;
+	char *xname;		/* XATTR name without prefix */
+	uint32_t name_len;	/* length of xname */
+	char *xvalue;		/* XATTR value */
+	uint32_t value_len;	/* length of xvalue */
+};
+
+struct jffs2_inode_cache;
+struct jffs2_xattr_ref
+{
+	void *always_null;
+	u8 class;
+	u8 flags;		/* Currently unused */
+	u16 unused;
+
+	struct jffs2_raw_node_ref *node;
+	union {
+		struct jffs2_inode_cache *ic;	/* reference to jffs2_inode_cache */
+		uint32_t ino;			/* only used in scanning/building  */
+	};
+	union {
+		struct jffs2_xattr_datum *xd;	/* reference to jffs2_xattr_datum */
+		uint32_t xid;			/* only used in sccanning/building */
+	};
+	struct jffs2_xattr_ref *next;		/* chained from ic->xref_list */
+};
+
+#ifdef CONFIG_JFFS2_FS_XATTR
+
+extern void jffs2_init_xattr_subsystem(struct jffs2_sb_info *c);
+extern void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c);
+extern void jffs2_clear_xattr_subsystem(struct jffs2_sb_info *c);
+
+extern struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
+                                                  uint32_t xid, uint32_t version);
+
+extern void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
+extern void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic);
+
+extern int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd);
+extern int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref);
+extern int jffs2_verify_xattr(struct jffs2_sb_info *c);
+
+extern int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
+			     char *buffer, size_t size);
+extern int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
+			     const char *buffer, size_t size, int flags);
+
+extern struct xattr_handler *jffs2_xattr_handlers[];
+extern struct xattr_handler jffs2_user_xattr_handler;
+extern struct xattr_handler jffs2_trusted_xattr_handler;
+
+extern ssize_t jffs2_listxattr(struct dentry *, char *, size_t);
+#define jffs2_getxattr		generic_getxattr
+#define jffs2_setxattr		generic_setxattr
+#define jffs2_removexattr	generic_removexattr
+
+#else
+
+#define jffs2_init_xattr_subsystem(c)
+#define jffs2_build_xattr_subsystem(c)
+#define jffs2_clear_xattr_subsystem(c)
+
+#define jffs2_xattr_delete_inode(c, ic)
+#define jffs2_xattr_free_inode(c, ic)
+#define jffs2_verify_xattr(c)			(1)
+
+#define jffs2_xattr_handlers	NULL
+#define jffs2_listxattr		NULL
+#define jffs2_getxattr		NULL
+#define jffs2_setxattr		NULL
+#define jffs2_removexattr	NULL
+
+#endif /* CONFIG_JFFS2_FS_XATTR */
+
+#ifdef CONFIG_JFFS2_FS_SECURITY
+extern int jffs2_init_security(struct inode *inode, struct inode *dir);
+extern struct xattr_handler jffs2_security_xattr_handler;
+#else
+#define jffs2_init_security(inode,dir)	(0)
+#endif /* CONFIG_JFFS2_FS_SECURITY */
+
+#endif /* _JFFS2_FS_XATTR_H_ */

fs/jffs2/xattr_trusted.c

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/jffs2.h>
+#include <linux/xattr.h>
+#include <linux/mtd/mtd.h>
+#include "nodelist.h"
+
+static int jffs2_trusted_getxattr(struct inode *inode, const char *name,
+				  void *buffer, size_t size)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+	return do_jffs2_getxattr(inode, JFFS2_XPREFIX_TRUSTED, name, buffer, size);
+}
+
+static int jffs2_trusted_setxattr(struct inode *inode, const char *name, const void *buffer,
+				  size_t size, int flags)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+	return do_jffs2_setxattr(inode, JFFS2_XPREFIX_TRUSTED, name, buffer, size, flags);
+}
+
+static size_t jffs2_trusted_listxattr(struct inode *inode, char *list, size_t list_size,
+				      const char *name, size_t name_len)
+{
+	size_t retlen = XATTR_TRUSTED_PREFIX_LEN + name_len + 1;
+
+	if (list && retlen<=list_size) {
+		strcpy(list, XATTR_TRUSTED_PREFIX);
+		strcpy(list + XATTR_TRUSTED_PREFIX_LEN, name);
+	}
+
+	return retlen;
+}
+
+struct xattr_handler jffs2_trusted_xattr_handler = {
+	.prefix = XATTR_TRUSTED_PREFIX,
+	.list = jffs2_trusted_listxattr,
+	.set = jffs2_trusted_setxattr,
+	.get = jffs2_trusted_getxattr
+};

fs/jffs2/xattr_user.c

+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2006  NEC Corporation
+ *
+ * Created by KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *
+ * For licensing information, see the file 'LICENCE' in this directory.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/jffs2.h>
+#include <linux/xattr.h>
+#include <linux/mtd/mtd.h>
+#include "nodelist.h"
+
+static int jffs2_user_getxattr(struct inode *inode, const char *name,
+                               void *buffer, size_t size)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+	return do_jffs2_getxattr(inode, JFFS2_XPREFIX_USER, name, buffer, size);
+}
+
+static int jffs2_user_setxattr(struct inode *inode, const char *name, const void *buffer,
+                               size_t size, int flags)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+	return do_jffs2_setxattr(inode, JFFS2_XPREFIX_USER, name, buffer, size, flags);
+}
+
+static size_t jffs2_user_listxattr(struct inode *inode, char *list, size_t list_size,
+				   const char *name, size_t name_len)
+{
+	size_t retlen = XATTR_USER_PREFIX_LEN + name_len + 1;
+
+	if (list && retlen <= list_size) {
+		strcpy(list, XATTR_USER_PREFIX);
+		strcpy(list + XATTR_USER_PREFIX_LEN, name);
+	}
+
+	return retlen;
+}
+
+struct xattr_handler jffs2_user_xattr_handler = {
+	.prefix = XATTR_USER_PREFIX,
+	.list = jffs2_user_listxattr,
+	.set = jffs2_user_setxattr,
+	.get = jffs2_user_getxattr
+};

include/linux/jffs2.h

@@ -65,6 +65,18 @@
 
 #define JFFS2_NODETYPE_SUMMARY (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 6)
 
+#define JFFS2_NODETYPE_XATTR (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 8)
+#define JFFS2_NODETYPE_XREF (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 9)
+
+/* XATTR Related */
+#define JFFS2_XPREFIX_USER		1	/* for "user." */
+#define JFFS2_XPREFIX_SECURITY		2	/* for "security." */
+#define JFFS2_XPREFIX_ACL_ACCESS	3	/* for "system.posix_acl_access" */
+#define JFFS2_XPREFIX_ACL_DEFAULT	4	/* for "system.posix_acl_default" */
+#define JFFS2_XPREFIX_TRUSTED		5	/* for "trusted.*" */
+
+#define JFFS2_ACL_VERSION		0x0001
+
 // Maybe later...
 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
@@ -151,6 +163,32 @@ struct jffs2_raw_inode
 	uint8_t data[0];
 };
 
+struct jffs2_raw_xattr {
+	jint16_t magic;
+	jint16_t nodetype;	/* = JFFS2_NODETYPE_XATTR */
+	jint32_t totlen;
+	jint32_t hdr_crc;
+	jint32_t xid;		/* XATTR identifier number */
+	jint32_t version;
+	uint8_t xprefix;
+	uint8_t name_len;
+	jint16_t value_len;
+	jint32_t data_crc;
+	jint32_t node_crc;
+	uint8_t data[0];
+} __attribute__((packed));
+
+struct jffs2_raw_xref
+{
+	jint16_t magic;
+	jint16_t nodetype;	/* = JFFS2_NODETYPE_XREF */
+	jint32_t totlen;
+	jint32_t hdr_crc;
+	jint32_t ino;		/* inode number */
+	jint32_t xid;		/* XATTR identifier number */
+	jint32_t node_crc;
+} __attribute__((packed));
+
 struct jffs2_raw_summary
 {
 	jint16_t magic;
@@ -169,6 +207,8 @@ union jffs2_node_union
 {
 	struct jffs2_raw_inode i;
 	struct jffs2_raw_dirent d;
+	struct jffs2_raw_xattr x;
+	struct jffs2_raw_xref r;
 	struct jffs2_raw_summary s;
 	struct jffs2_unknown_node u;
 };