|  | /* | 
|  | * 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 "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 name_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; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | total_len = prefix_len + name_len + 1; | 
|  | if (list && total_len <= list_size) { | 
|  | memcpy(list, prefix, prefix_len); | 
|  | memcpy(list+prefix_len, name, name_len); | 
|  | list[prefix_len + name_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; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  | if (strcmp(name, "") == 0) | 
|  | return -EINVAL; | 
|  | return f2fs_getxattr(dentry->d_inode, type, name, | 
|  | buffer, size); | 
|  | } | 
|  |  | 
|  | 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; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  | if (strcmp(name, "") == 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | return f2fs_setxattr(dentry->d_inode, type, name, value, size); | 
|  | } | 
|  |  | 
|  | static size_t f2fs_xattr_advise_list(struct dentry *dentry, char *list, | 
|  | size_t list_size, const char *name, size_t name_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 = dentry->d_inode; | 
|  |  | 
|  | if (strcmp(name, "") != 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | *((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 = dentry->d_inode; | 
|  |  | 
|  | 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; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | 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, | 
|  | }; | 
|  |  | 
|  | 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] = &f2fs_xattr_acl_access_handler, | 
|  | [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &f2fs_xattr_acl_default_handler, | 
|  | #endif | 
|  | [F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler, | 
|  | [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 | 
|  | &f2fs_xattr_acl_access_handler, | 
|  | &f2fs_xattr_acl_default_handler, | 
|  | #endif | 
|  | &f2fs_xattr_trusted_handler, | 
|  | &f2fs_xattr_advise_handler, | 
|  | NULL, | 
|  | }; | 
|  |  | 
|  | static inline const struct xattr_handler *f2fs_xattr_handler(int name_index) | 
|  | { | 
|  | const struct xattr_handler *handler = NULL; | 
|  |  | 
|  | if (name_index > 0 && name_index < ARRAY_SIZE(f2fs_xattr_handler_map)) | 
|  | handler = f2fs_xattr_handler_map[name_index]; | 
|  | return handler; | 
|  | } | 
|  |  | 
|  | int f2fs_getxattr(struct inode *inode, int name_index, const char *name, | 
|  | void *buffer, size_t buffer_size) | 
|  | { | 
|  | struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); | 
|  | struct f2fs_inode_info *fi = F2FS_I(inode); | 
|  | struct f2fs_xattr_entry *entry; | 
|  | struct page *page; | 
|  | void *base_addr; | 
|  | int error = 0, found = 0; | 
|  | size_t value_len, name_len; | 
|  |  | 
|  | if (name == NULL) | 
|  | return -EINVAL; | 
|  | name_len = strlen(name); | 
|  |  | 
|  | if (!fi->i_xattr_nid) | 
|  | return -ENODATA; | 
|  |  | 
|  | page = get_node_page(sbi, fi->i_xattr_nid); | 
|  | base_addr = page_address(page); | 
|  |  | 
|  | list_for_each_xattr(entry, base_addr) { | 
|  | if (entry->e_name_index != name_index) | 
|  | continue; | 
|  | if (entry->e_name_len != name_len) | 
|  | continue; | 
|  | if (!memcmp(entry->e_name, name, name_len)) { | 
|  | found = 1; | 
|  | break; | 
|  | } | 
|  | } | 
|  | if (!found) { | 
|  | error = -ENODATA; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | value_len = le16_to_cpu(entry->e_value_size); | 
|  |  | 
|  | if (buffer && value_len > buffer_size) { | 
|  | error = -ERANGE; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | if (buffer) { | 
|  | char *pval = entry->e_name + entry->e_name_len; | 
|  | memcpy(buffer, pval, value_len); | 
|  | } | 
|  | error = value_len; | 
|  |  | 
|  | cleanup: | 
|  | f2fs_put_page(page, 1); | 
|  | return error; | 
|  | } | 
|  |  | 
|  | ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) | 
|  | { | 
|  | struct inode *inode = dentry->d_inode; | 
|  | struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); | 
|  | struct f2fs_inode_info *fi = F2FS_I(inode); | 
|  | struct f2fs_xattr_entry *entry; | 
|  | struct page *page; | 
|  | void *base_addr; | 
|  | int error = 0; | 
|  | size_t rest = buffer_size; | 
|  |  | 
|  | if (!fi->i_xattr_nid) | 
|  | return 0; | 
|  |  | 
|  | page = get_node_page(sbi, fi->i_xattr_nid); | 
|  | base_addr = page_address(page); | 
|  |  | 
|  | 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: | 
|  | f2fs_put_page(page, 1); | 
|  | return error; | 
|  | } | 
|  |  | 
|  | int f2fs_setxattr(struct inode *inode, int name_index, const char *name, | 
|  | const void *value, size_t value_len) | 
|  | { | 
|  | struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); | 
|  | struct f2fs_inode_info *fi = F2FS_I(inode); | 
|  | struct f2fs_xattr_header *header = NULL; | 
|  | struct f2fs_xattr_entry *here, *last; | 
|  | struct page *page; | 
|  | void *base_addr; | 
|  | int error, found, free, newsize; | 
|  | size_t name_len; | 
|  | char *pval; | 
|  |  | 
|  | if (name == NULL) | 
|  | return -EINVAL; | 
|  | name_len = strlen(name); | 
|  |  | 
|  | if (value == NULL) | 
|  | value_len = 0; | 
|  |  | 
|  | if (name_len > 255 || value_len > MAX_VALUE_LEN) | 
|  | return -ERANGE; | 
|  |  | 
|  | f2fs_balance_fs(sbi); | 
|  |  | 
|  | mutex_lock_op(sbi, NODE_NEW); | 
|  | if (!fi->i_xattr_nid) { | 
|  | /* Allocate new attribute block */ | 
|  | struct dnode_of_data dn; | 
|  |  | 
|  | if (!alloc_nid(sbi, &fi->i_xattr_nid)) { | 
|  | mutex_unlock_op(sbi, NODE_NEW); | 
|  | return -ENOSPC; | 
|  | } | 
|  | set_new_dnode(&dn, inode, NULL, NULL, fi->i_xattr_nid); | 
|  | mark_inode_dirty(inode); | 
|  |  | 
|  | page = new_node_page(&dn, XATTR_NODE_OFFSET); | 
|  | if (IS_ERR(page)) { | 
|  | alloc_nid_failed(sbi, fi->i_xattr_nid); | 
|  | fi->i_xattr_nid = 0; | 
|  | mutex_unlock_op(sbi, NODE_NEW); | 
|  | return PTR_ERR(page); | 
|  | } | 
|  |  | 
|  | alloc_nid_done(sbi, fi->i_xattr_nid); | 
|  | base_addr = page_address(page); | 
|  | header = XATTR_HDR(base_addr); | 
|  | header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC); | 
|  | header->h_refcount = cpu_to_le32(1); | 
|  | } else { | 
|  | /* The inode already has an extended attribute block. */ | 
|  | page = get_node_page(sbi, fi->i_xattr_nid); | 
|  | if (IS_ERR(page)) { | 
|  | mutex_unlock_op(sbi, NODE_NEW); | 
|  | return PTR_ERR(page); | 
|  | } | 
|  |  | 
|  | base_addr = page_address(page); | 
|  | header = XATTR_HDR(base_addr); | 
|  | } | 
|  |  | 
|  | if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) { | 
|  | error = -EIO; | 
|  | goto cleanup; | 
|  | } | 
|  |  | 
|  | /* find entry with wanted name. */ | 
|  | found = 0; | 
|  | list_for_each_xattr(here, base_addr) { | 
|  | if (here->e_name_index != name_index) | 
|  | continue; | 
|  | if (here->e_name_len != name_len) | 
|  | continue; | 
|  | if (!memcmp(here->e_name, name, name_len)) { | 
|  | found = 1; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | last = here; | 
|  |  | 
|  | while (!IS_XATTR_LAST_ENTRY(last)) | 
|  | last = XATTR_NEXT_ENTRY(last); | 
|  |  | 
|  | newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + | 
|  | name_len + value_len); | 
|  |  | 
|  | /* 1. Check space */ | 
|  | if (value) { | 
|  | /* If value is NULL, it is remove operation. | 
|  | * In case of update operation, we caculate free. | 
|  | */ | 
|  | free = MIN_OFFSET - ((char *)last - (char *)header); | 
|  | if (found) | 
|  | free = free - ENTRY_SIZE(here); | 
|  |  | 
|  | if (free < newsize) { | 
|  | error = -ENOSPC; | 
|  | goto cleanup; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* 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); | 
|  | } | 
|  |  | 
|  | /* 3. Write new entry */ | 
|  | if (value) { | 
|  | /* Before we come here, old entry is removed. | 
|  | * We just write new entry. */ | 
|  | memset(last, 0, newsize); | 
|  | last->e_name_index = name_index; | 
|  | last->e_name_len = name_len; | 
|  | memcpy(last->e_name, name, name_len); | 
|  | pval = last->e_name + name_len; | 
|  | memcpy(pval, value, value_len); | 
|  | last->e_value_size = cpu_to_le16(value_len); | 
|  | } | 
|  |  | 
|  | set_page_dirty(page); | 
|  | f2fs_put_page(page, 1); | 
|  |  | 
|  | 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); | 
|  | } | 
|  | f2fs_write_inode(inode, NULL); | 
|  | mutex_unlock_op(sbi, NODE_NEW); | 
|  |  | 
|  | return 0; | 
|  | cleanup: | 
|  | f2fs_put_page(page, 1); | 
|  | mutex_unlock_op(sbi, NODE_NEW); | 
|  | return error; | 
|  | } |