This patchset moves the "FS read I/O callbacks" code into a file of its own (i.e. fs/read_callbacks.c) and modifies the generic do_mpage_readpge() to make use of the functionality provided. "FS read I/O callbacks" code implements the state machine that needs to be executed after reading data from files that are encrypted and/or have verity metadata associated with them. With these changes in place, the patchset changes Ext4 to use mpage_readpage[s] instead of its own custom ext4_readpage[s]() functions. This is done to reduce duplicity of code across filesystems. Also, "FS read I/O callbacks" source files will be built only if one of CONFIG_FS_ENCRYPTION and CONFIG_FS_VERITY is enabled. The patchset also modifies fs/buffer.c and fscrypt functionality to get file encryption/decryption to work with subpage-sized blocks. The following fixes from Eric Biggers are prerequisites for this patchset, fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext fscrypt: only set dentry_operations on ciphertext dentries fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory fscrypt: fix race allowing rename() and link() of ciphertext dentries fscrypt: clean up and improve dentry revalidation The patches can also be obtained from, "https://github.com/chandanr/linux.git subpage-encryption-v2" Changelog: V1 -> V2: 1. Removed the phrase "post_read_process" from file names and functions. Instead we now use the phrase "read_callbacks" in its place. 2. When performing changes associated with (1), the changes made by the patch "Remove the term 'bio' from post read processing" are made in the earlier patch "Consolidate 'read callbacks' into a new file". Hence the patch "Remove the term 'bio' from post read processing" is removed from the patchset. RFC V2 -> V1: 1. Test and verify FS_CFLG_OWN_PAGES subset of fscrypt_encrypt_page() code by executing fstests on UBIFS. 2. Implement F2fs function call back to check if the contents of a page holding a verity file's data needs to be verified. RFC V1 -> RFC V2: 1. Describe the purpose of "Post processing code" in the cover letter. 2. Fix build errors when CONFIG_FS_VERITY is enabled. Chandan Rajendra (13): ext4: Clear BH_Uptodate flag on decryption error Consolidate "read callbacks" into a new file fsverity: Add call back to decide if verity check has to be performed fsverity: Add call back to determine readpage limit fs/mpage.c: Integrate read callbacks ext4: Wire up ext4_readpage[s] to use mpage_readpage[s] Add decryption support for sub-pagesized blocks ext4: Decrypt all boundary blocks when doing buffered write ext4: Decrypt the block that needs to be partially zeroed fscrypt_encrypt_page: Loop across all blocks mapped by a page range ext4: Compute logical block and the page range to be encrypted fscrypt_zeroout_range: Encrypt all zeroed out blocks of a page ext4: Enable encryption for subpage-sized blocks Documentation/filesystems/fscrypt.rst | 4 +- fs/Kconfig | 4 + fs/Makefile | 4 + fs/buffer.c | 83 +++-- fs/crypto/Kconfig | 1 + fs/crypto/bio.c | 111 ++++--- fs/crypto/crypto.c | 73 +++-- fs/crypto/fscrypt_private.h | 3 + fs/ext4/Makefile | 2 +- fs/ext4/ext4.h | 2 - fs/ext4/inode.c | 47 ++- fs/ext4/page-io.c | 9 +- fs/ext4/readpage.c | 445 -------------------------- fs/ext4/super.c | 39 ++- fs/f2fs/data.c | 148 ++------- fs/f2fs/super.c | 15 +- fs/mpage.c | 51 ++- fs/read_callbacks.c | 155 +++++++++ fs/verity/Kconfig | 1 + fs/verity/verify.c | 12 + include/linux/buffer_head.h | 1 + include/linux/fscrypt.h | 20 +- include/linux/fsverity.h | 2 + include/linux/read_callbacks.h | 22 ++ 24 files changed, 522 insertions(+), 732 deletions(-) delete mode 100644 fs/ext4/readpage.c create mode 100644 fs/read_callbacks.c create mode 100644 include/linux/read_callbacks.h -- 2.19.1
