diff options
Diffstat (limited to 'fs/crypto/crypto.c')
| -rw-r--r-- | fs/crypto/crypto.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c index ff43a13c3abf..f82c45ac285a 100644 --- a/fs/crypto/crypto.c +++ b/fs/crypto/crypto.c @@ -285,8 +285,7 @@ EXPORT_SYMBOL(fscrypt_encrypt_block_inplace); /** * fscrypt_decrypt_page() - Decrypts a page in-place * @inode: The corresponding inode for the page to decrypt. - * @page: The page to decrypt. Must be locked in case - * it is a writeback page (FS_CFLG_OWN_PAGES unset). + * @page: The page to decrypt. Must be locked. * @len: Number of bytes in @page to be decrypted. * @offs: Start of data in @page. * @lblk_num: Logical block number. @@ -300,8 +299,7 @@ EXPORT_SYMBOL(fscrypt_encrypt_block_inplace); int fscrypt_decrypt_page(const struct inode *inode, struct page *page, unsigned int len, unsigned int offs, u64 lblk_num) { - if (WARN_ON_ONCE(!PageLocked(page) && - !(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES))) + if (WARN_ON_ONCE(!PageLocked(page))) return -EINVAL; return fscrypt_crypt_block(inode, FS_DECRYPT, lblk_num, page, page, @@ -309,6 +307,31 @@ int fscrypt_decrypt_page(const struct inode *inode, struct page *page, } EXPORT_SYMBOL(fscrypt_decrypt_page); +/** + * fscrypt_decrypt_block_inplace() - Decrypt a filesystem block in-place + * @inode: The inode to which this block belongs + * @page: The page containing the block to decrypt + * @len: Size of block to decrypt. Doesn't need to be a multiple of the + * fs block size, but must be a multiple of FS_CRYPTO_BLOCK_SIZE. + * @offs: Byte offset within @page at which the block to decrypt begins + * @lblk_num: Filesystem logical block number of the block, i.e. the 0-based + * number of the block within the file + * + * Decrypt a possibly-compressed filesystem block that is located in an + * arbitrary page, not necessarily in the original pagecache page. The @inode + * and @lblk_num must be specified, as they can't be determined from @page. + * + * Return: 0 on success; -errno on failure + */ +int fscrypt_decrypt_block_inplace(const struct inode *inode, struct page *page, + unsigned int len, unsigned int offs, + u64 lblk_num) +{ + return fscrypt_crypt_block(inode, FS_DECRYPT, lblk_num, page, page, + len, offs, GFP_NOFS); +} +EXPORT_SYMBOL(fscrypt_decrypt_block_inplace); + /* * Validate dentries in encrypted directories to make sure we aren't potentially * caching stale dentries after a key has been added. |