Initial import

1 files changed, 618 insertions, 0 deletions

diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
new file mode 100644
index 000000000..9757f65a0
--- /dev/null
+++ b/fs/f2fs/xattr.c
@@ -0,0 +1,618 @@
+/*
+ * fs/f2fs/xattr.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *             http://www.samsung.com/
+ *
+ * Portions of this code from linux/fs/ext2/xattr.c
+ *
+ * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de>
+ *
+ * Fix by Harrison Xing <harrison@mountainviewdata.com>.
+ * Extended attributes for symlinks and special files added per
+ *  suggestion of Luka Renko <luka.renko@hermes.si>.
+ * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
+ *  Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/rwsem.h>
+#include <linux/f2fs_fs.h>
+#include <linux/security.h>
+#include <linux/posix_acl_xattr.h>
+#include "f2fs.h"
+#include "xattr.h"
+
+static size_t f2fs_xattr_generic_list(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t len, int type)
+{
+	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
+	int total_len, prefix_len = 0;
+	const char *prefix = NULL;
+
+	switch (type) {
+	case F2FS_XATTR_INDEX_USER:
+		if (!test_opt(sbi, XATTR_USER))
+			return -EOPNOTSUPP;
+		prefix = XATTR_USER_PREFIX;
+		prefix_len = XATTR_USER_PREFIX_LEN;
+		break;
+	case F2FS_XATTR_INDEX_TRUSTED:
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		prefix = XATTR_TRUSTED_PREFIX;
+		prefix_len = XATTR_TRUSTED_PREFIX_LEN;
+		break;
+	case F2FS_XATTR_INDEX_SECURITY:
+		prefix = XATTR_SECURITY_PREFIX;
+		prefix_len = XATTR_SECURITY_PREFIX_LEN;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	total_len = prefix_len + len + 1;
+	if (list && total_len <= list_size) {
+		memcpy(list, prefix, prefix_len);
+		memcpy(list + prefix_len, name, len);
+		list[prefix_len + len] = '\0';
+	}
+	return total_len;
+}
+
+static int f2fs_xattr_generic_get(struct dentry *dentry, const char *name,
+		void *buffer, size_t size, int type)
+{
+	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
+
+	switch (type) {
+	case F2FS_XATTR_INDEX_USER:
+		if (!test_opt(sbi, XATTR_USER))
+			return -EOPNOTSUPP;
+		break;
+	case F2FS_XATTR_INDEX_TRUSTED:
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		break;
+	case F2FS_XATTR_INDEX_SECURITY:
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+	return f2fs_getxattr(d_inode(dentry), type, name, buffer, size, NULL);
+}
+
+static int f2fs_xattr_generic_set(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags, int type)
+{
+	struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb);
+
+	switch (type) {
+	case F2FS_XATTR_INDEX_USER:
+		if (!test_opt(sbi, XATTR_USER))
+			return -EOPNOTSUPP;
+		break;
+	case F2FS_XATTR_INDEX_TRUSTED:
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+		break;
+	case F2FS_XATTR_INDEX_SECURITY:
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (strcmp(name, "") == 0)
+		return -EINVAL;
+
+	return f2fs_setxattr(d_inode(dentry), type, name,
+					value, size, NULL, flags);
+}
+
+static size_t f2fs_xattr_advise_list(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t len, int type)
+{
+	const char *xname = F2FS_SYSTEM_ADVISE_PREFIX;
+	size_t size;
+
+	if (type != F2FS_XATTR_INDEX_ADVISE)
+		return 0;
+
+	size = strlen(xname) + 1;
+	if (list && size <= list_size)
+		memcpy(list, xname, size);
+	return size;
+}
+
+static int f2fs_xattr_advise_get(struct dentry *dentry, const char *name,
+		void *buffer, size_t size, int type)
+{
+	struct inode *inode = d_inode(dentry);
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+
+	if (buffer)
+		*((char *)buffer) = F2FS_I(inode)->i_advise;
+	return sizeof(char);
+}
+
+static int f2fs_xattr_advise_set(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags, int type)
+{
+	struct inode *inode = d_inode(dentry);
+
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+	if (!inode_owner_or_capable(inode))
+		return -EPERM;
+	if (value == NULL)
+		return -EINVAL;
+
+	F2FS_I(inode)->i_advise |= *(char *)value;
+	mark_inode_dirty(inode);
+	return 0;
+}
+
+#ifdef CONFIG_F2FS_FS_SECURITY
+static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+		void *page)
+{
+	const struct xattr *xattr;
+	int err = 0;
+
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+		err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY,
+				xattr->name, xattr->value,
+				xattr->value_len, (struct page *)page, 0);
+		if (err < 0)
+			break;
+	}
+	return err;
+}
+
+int f2fs_init_security(struct inode *inode, struct inode *dir,
+				const struct qstr *qstr, struct page *ipage)
+{
+	return security_inode_init_security(inode, dir, qstr,
+				&f2fs_initxattrs, ipage);
+}
+#endif
+
+const struct xattr_handler f2fs_xattr_user_handler = {
+	.prefix	= XATTR_USER_PREFIX,
+	.flags	= F2FS_XATTR_INDEX_USER,
+	.list	= f2fs_xattr_generic_list,
+	.get	= f2fs_xattr_generic_get,
+	.set	= f2fs_xattr_generic_set,
+};
+
+const struct xattr_handler f2fs_xattr_trusted_handler = {
+	.prefix	= XATTR_TRUSTED_PREFIX,
+	.flags	= F2FS_XATTR_INDEX_TRUSTED,
+	.list	= f2fs_xattr_generic_list,
+	.get	= f2fs_xattr_generic_get,
+	.set	= f2fs_xattr_generic_set,
+};
+
+const struct xattr_handler f2fs_xattr_advise_handler = {
+	.prefix = F2FS_SYSTEM_ADVISE_PREFIX,
+	.flags	= F2FS_XATTR_INDEX_ADVISE,
+	.list   = f2fs_xattr_advise_list,
+	.get    = f2fs_xattr_advise_get,
+	.set    = f2fs_xattr_advise_set,
+};
+
+const struct xattr_handler f2fs_xattr_security_handler = {
+	.prefix	= XATTR_SECURITY_PREFIX,
+	.flags	= F2FS_XATTR_INDEX_SECURITY,
+	.list	= f2fs_xattr_generic_list,
+	.get	= f2fs_xattr_generic_get,
+	.set	= f2fs_xattr_generic_set,
+};
+
+static const struct xattr_handler *f2fs_xattr_handler_map[] = {
+	[F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler,
+#ifdef CONFIG_F2FS_FS_POSIX_ACL
+	[F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler,
+	[F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler,
+#endif
+	[F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler,
+#ifdef CONFIG_F2FS_FS_SECURITY
+	[F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler,
+#endif
+	[F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler,
+};
+
+const struct xattr_handler *f2fs_xattr_handlers[] = {
+	&f2fs_xattr_user_handler,
+#ifdef CONFIG_F2FS_FS_POSIX_ACL
+	&posix_acl_access_xattr_handler,
+	&posix_acl_default_xattr_handler,
+#endif
+	&f2fs_xattr_trusted_handler,
+#ifdef CONFIG_F2FS_FS_SECURITY
+	&f2fs_xattr_security_handler,
+#endif
+	&f2fs_xattr_advise_handler,
+	NULL,
+};
+
+static inline const struct xattr_handler *f2fs_xattr_handler(int index)
+{
+	const struct xattr_handler *handler = NULL;
+
+	if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map))
+		handler = f2fs_xattr_handler_map[index];
+	return handler;
+}
+
+static struct f2fs_xattr_entry *__find_xattr(void *base_addr, int index,
+					size_t len, const char *name)
+{
+	struct f2fs_xattr_entry *entry;
+
+	list_for_each_xattr(entry, base_addr) {
+		if (entry->e_name_index != index)
+			continue;
+		if (entry->e_name_len != len)
+			continue;
+		if (!memcmp(entry->e_name, name, len))
+			break;
+	}
+	return entry;
+}
+
+static void *read_all_xattrs(struct inode *inode, struct page *ipage)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct f2fs_xattr_header *header;
+	size_t size = PAGE_SIZE, inline_size = 0;
+	void *txattr_addr;
+
+	inline_size = inline_xattr_size(inode);
+
+	txattr_addr = kzalloc(inline_size + size, GFP_F2FS_ZERO);
+	if (!txattr_addr)
+		return NULL;
+
+	/* read from inline xattr */
+	if (inline_size) {
+		struct page *page = NULL;
+		void *inline_addr;
+
+		if (ipage) {
+			inline_addr = inline_xattr_addr(ipage);
+		} else {
+			page = get_node_page(sbi, inode->i_ino);
+			if (IS_ERR(page))
+				goto fail;
+			inline_addr = inline_xattr_addr(page);
+		}
+		memcpy(txattr_addr, inline_addr, inline_size);
+		f2fs_put_page(page, 1);
+	}
+
+	/* read from xattr node block */
+	if (F2FS_I(inode)->i_xattr_nid) {
+		struct page *xpage;
+		void *xattr_addr;
+
+		/* The inode already has an extended attribute block. */
+		xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
+		if (IS_ERR(xpage))
+			goto fail;
+
+		xattr_addr = page_address(xpage);
+		memcpy(txattr_addr + inline_size, xattr_addr, PAGE_SIZE);
+		f2fs_put_page(xpage, 1);
+	}
+
+	header = XATTR_HDR(txattr_addr);
+
+	/* never been allocated xattrs */
+	if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) {
+		header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC);
+		header->h_refcount = cpu_to_le32(1);
+	}
+	return txattr_addr;
+fail:
+	kzfree(txattr_addr);
+	return NULL;
+}
+
+static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
+				void *txattr_addr, struct page *ipage)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	size_t inline_size = 0;
+	void *xattr_addr;
+	struct page *xpage;
+	nid_t new_nid = 0;
+	int err;
+
+	inline_size = inline_xattr_size(inode);
+
+	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
+		if (!alloc_nid(sbi, &new_nid))
+			return -ENOSPC;
+
+	/* write to inline xattr */
+	if (inline_size) {
+		struct page *page = NULL;
+		void *inline_addr;
+
+		if (ipage) {
+			inline_addr = inline_xattr_addr(ipage);
+			f2fs_wait_on_page_writeback(ipage, NODE);
+		} else {
+			page = get_node_page(sbi, inode->i_ino);
+			if (IS_ERR(page)) {
+				alloc_nid_failed(sbi, new_nid);
+				return PTR_ERR(page);
+			}
+			inline_addr = inline_xattr_addr(page);
+			f2fs_wait_on_page_writeback(page, NODE);
+		}
+		memcpy(inline_addr, txattr_addr, inline_size);
+		f2fs_put_page(page, 1);
+
+		/* no need to use xattr node block */
+		if (hsize <= inline_size) {
+			err = truncate_xattr_node(inode, ipage);
+			alloc_nid_failed(sbi, new_nid);
+			return err;
+		}
+	}
+
+	/* write to xattr node block */
+	if (F2FS_I(inode)->i_xattr_nid) {
+		xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
+		if (IS_ERR(xpage)) {
+			alloc_nid_failed(sbi, new_nid);
+			return PTR_ERR(xpage);
+		}
+		f2fs_bug_on(sbi, new_nid);
+		f2fs_wait_on_page_writeback(xpage, NODE);
+	} else {
+		struct dnode_of_data dn;
+		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
+		xpage = new_node_page(&dn, XATTR_NODE_OFFSET, ipage);
+		if (IS_ERR(xpage)) {
+			alloc_nid_failed(sbi, new_nid);
+			return PTR_ERR(xpage);
+		}
+		alloc_nid_done(sbi, new_nid);
+	}
+
+	xattr_addr = page_address(xpage);
+	memcpy(xattr_addr, txattr_addr + inline_size, PAGE_SIZE -
+						sizeof(struct node_footer));
+	set_page_dirty(xpage);
+	f2fs_put_page(xpage, 1);
+
+	/* need to checkpoint during fsync */
+	F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
+	return 0;
+}
+
+int f2fs_getxattr(struct inode *inode, int index, const char *name,
+		void *buffer, size_t buffer_size, struct page *ipage)
+{
+	struct f2fs_xattr_entry *entry;
+	void *base_addr;
+	int error = 0;
+	size_t size, len;
+
+	if (name == NULL)
+		return -EINVAL;
+
+	len = strlen(name);
+	if (len > F2FS_NAME_LEN)
+		return -ERANGE;
+
+	base_addr = read_all_xattrs(inode, ipage);
+	if (!base_addr)
+		return -ENOMEM;
+
+	entry = __find_xattr(base_addr, index, len, name);
+	if (IS_XATTR_LAST_ENTRY(entry)) {
+		error = -ENODATA;
+		goto cleanup;
+	}
+
+	size = le16_to_cpu(entry->e_value_size);
+
+	if (buffer && size > buffer_size) {
+		error = -ERANGE;
+		goto cleanup;
+	}
+
+	if (buffer) {
+		char *pval = entry->e_name + entry->e_name_len;
+		memcpy(buffer, pval, size);
+	}
+	error = size;
+
+cleanup:
+	kzfree(base_addr);
+	return error;
+}
+
+ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size)
+{
+	struct inode *inode = d_inode(dentry);
+	struct f2fs_xattr_entry *entry;
+	void *base_addr;
+	int error = 0;
+	size_t rest = buffer_size;
+
+	base_addr = read_all_xattrs(inode, NULL);
+	if (!base_addr)
+		return -ENOMEM;
+
+	list_for_each_xattr(entry, base_addr) {
+		const struct xattr_handler *handler =
+			f2fs_xattr_handler(entry->e_name_index);
+		size_t size;
+
+		if (!handler)
+			continue;
+
+		size = handler->list(dentry, buffer, rest, entry->e_name,
+				entry->e_name_len, handler->flags);
+		if (buffer && size > rest) {
+			error = -ERANGE;
+			goto cleanup;
+		}
+
+		if (buffer)
+			buffer += size;
+		rest -= size;
+	}
+	error = buffer_size - rest;
+cleanup:
+	kzfree(base_addr);
+	return error;
+}
+
+static int __f2fs_setxattr(struct inode *inode, int index,
+			const char *name, const void *value, size_t size,
+			struct page *ipage, int flags)
+{
+	struct f2fs_inode_info *fi = F2FS_I(inode);
+	struct f2fs_xattr_entry *here, *last;
+	void *base_addr;
+	int found, newsize;
+	size_t len;
+	__u32 new_hsize;
+	int error = -ENOMEM;
+
+	if (name == NULL)
+		return -EINVAL;
+
+	if (value == NULL)
+		size = 0;
+
+	len = strlen(name);
+
+	if (len > F2FS_NAME_LEN || size > MAX_VALUE_LEN(inode))
+		return -ERANGE;
+
+	base_addr = read_all_xattrs(inode, ipage);
+	if (!base_addr)
+		goto exit;
+
+	/* find entry with wanted name. */
+	here = __find_xattr(base_addr, index, len, name);
+
+	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
+
+	if ((flags & XATTR_REPLACE) && !found) {
+		error = -ENODATA;
+		goto exit;
+	} else if ((flags & XATTR_CREATE) && found) {
+		error = -EEXIST;
+		goto exit;
+	}
+
+	last = here;
+	while (!IS_XATTR_LAST_ENTRY(last))
+		last = XATTR_NEXT_ENTRY(last);
+
+	newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size);
+
+	/* 1. Check space */
+	if (value) {
+		int free;
+		/*
+		 * If value is NULL, it is remove operation.
+		 * In case of update operation, we calculate free.
+		 */
+		free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr);
+		if (found)
+			free = free + ENTRY_SIZE(here);
+
+		if (unlikely(free < newsize)) {
+			error = -ENOSPC;
+			goto exit;
+		}
+	}
+
+	/* 2. Remove old entry */
+	if (found) {
+		/*
+		 * If entry is found, remove old entry.
+		 * If not found, remove operation is not needed.
+		 */
+		struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here);
+		int oldsize = ENTRY_SIZE(here);
+
+		memmove(here, next, (char *)last - (char *)next);
+		last = (struct f2fs_xattr_entry *)((char *)last - oldsize);
+		memset(last, 0, oldsize);
+	}
+
+	new_hsize = (char *)last - (char *)base_addr;
+
+	/* 3. Write new entry */
+	if (value) {
+		char *pval;
+		/*
+		 * Before we come here, old entry is removed.
+		 * We just write new entry.
+		 */
+		memset(last, 0, newsize);
+		last->e_name_index = index;
+		last->e_name_len = len;
+		memcpy(last->e_name, name, len);
+		pval = last->e_name + len;
+		memcpy(pval, value, size);
+		last->e_value_size = cpu_to_le16(size);
+		new_hsize += newsize;
+	}
+
+	error = write_all_xattrs(inode, new_hsize, base_addr, ipage);
+	if (error)
+		goto exit;
+
+	if (is_inode_flag_set(fi, FI_ACL_MODE)) {
+		inode->i_mode = fi->i_acl_mode;
+		inode->i_ctime = CURRENT_TIME;
+		clear_inode_flag(fi, FI_ACL_MODE);
+	}
+
+	if (ipage)
+		update_inode(inode, ipage);
+	else
+		update_inode_page(inode);
+exit:
+	kzfree(base_addr);
+	return error;
+}
+
+int f2fs_setxattr(struct inode *inode, int index, const char *name,
+				const void *value, size_t size,
+				struct page *ipage, int flags)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	int err;
+
+	/* this case is only from init_inode_metadata */
+	if (ipage)
+		return __f2fs_setxattr(inode, index, name, value,
+						size, ipage, flags);
+	f2fs_balance_fs(sbi);
+
+	f2fs_lock_op(sbi);
+	/* protect xattr_ver */
+	down_write(&F2FS_I(inode)->i_sem);
+	err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
+	up_write(&F2FS_I(inode)->i_sem);
+	f2fs_unlock_op(sbi);
+
+	return err;
+}