| /* |
| * 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; |
| } |