diff options
Diffstat (limited to 'kernel/fs/f2fs/xattr.c')
| -rw-r--r-- | kernel/fs/f2fs/xattr.c | 618 |
1 files changed, 618 insertions, 0 deletions
diff --git a/kernel/fs/f2fs/xattr.c b/kernel/fs/f2fs/xattr.c new file mode 100644 index 000000000..9757f65a0 --- /dev/null +++ b/kernel/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; +} |