diff options
Diffstat (limited to 'fs/f2fs/xattr.c')
-rw-r--r-- | fs/f2fs/xattr.c | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c new file mode 100644 index 0000000..aca50fe --- /dev/null +++ b/fs/f2fs/xattr.c @@ -0,0 +1,389 @@ +/** + * 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); +} + +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, +}; + +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; + int 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, name_len, newsize; + 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; + + 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; +} |