diff mbox series

[v6,9/9] ext4: add inline encryption support

Message ID 20191218145136.172774-10-satyat@google.com (mailing list archive)
State New, archived
Headers show
Series Inline Encryption Support | expand

Commit Message

Satya Tangirala Dec. 18, 2019, 2:51 p.m. UTC
Wire up ext4 to support inline encryption via the helper functions which
fs/crypto/ now provides.  This includes:

- Adding a mount option 'inlinecrypt' which enables inline encryption
  on encrypted files where it can be used.

- Setting the bio_crypt_ctx on bios that will be submitted to an
  inline-encrypted file.

  Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for
  this part, since ext4 sometimes uses ll_rw_block() on file data.

- Not adding logically discontiguous data to bios that will be submitted
  to an inline-encrypted file.

- Not doing filesystem-layer crypto on inline-encrypted files.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
---
 fs/buffer.c        |  2 ++
 fs/ext4/ext4.h     |  1 +
 fs/ext4/inode.c    |  4 ++--
 fs/ext4/page-io.c  |  6 ++++--
 fs/ext4/readpage.c | 11 ++++++++---
 fs/ext4/super.c    | 13 +++++++++++++
 6 files changed, 30 insertions(+), 7 deletions(-)

Comments

Eric Biggers Dec. 19, 2019, 12:12 a.m. UTC | #1
[+Cc linux-ext4]

On Wed, Dec 18, 2019 at 06:51:36AM -0800, Satya Tangirala wrote:
> Wire up ext4 to support inline encryption via the helper functions which
> fs/crypto/ now provides.  This includes:
> 
> - Adding a mount option 'inlinecrypt' which enables inline encryption
>   on encrypted files where it can be used.
> 
> - Setting the bio_crypt_ctx on bios that will be submitted to an
>   inline-encrypted file.
> 
>   Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for
>   this part, since ext4 sometimes uses ll_rw_block() on file data.
> 
> - Not adding logically discontiguous data to bios that will be submitted
>   to an inline-encrypted file.
> 
> - Not doing filesystem-layer crypto on inline-encrypted files.
> 
> Signed-off-by: Eric Biggers <ebiggers@google.com>
> Signed-off-by: Satya Tangirala <satyat@google.com>

In the next version can you please add linux-ext4 to Cc for the series?

> ---
>  fs/buffer.c        |  2 ++
>  fs/ext4/ext4.h     |  1 +
>  fs/ext4/inode.c    |  4 ++--
>  fs/ext4/page-io.c  |  6 ++++--
>  fs/ext4/readpage.c | 11 ++++++++---
>  fs/ext4/super.c    | 13 +++++++++++++
>  6 files changed, 30 insertions(+), 7 deletions(-)
> 
> diff --git a/fs/buffer.c b/fs/buffer.c
> index d8c7242426bb..3ad000db4a19 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -3108,6 +3108,8 @@ static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
>  	 */
>  	bio = bio_alloc(GFP_NOIO, 1);
>  
> +	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
> +
>  	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
>  	bio_set_dev(bio, bh->b_bdev);
>  	bio->bi_write_hint = write_hint;

In 5.5, there was some decryption code added to fs/buffer.c in order to support
ext4 encryption with blocksize < PAGE_SIZE:

static void end_buffer_async_read_io(struct buffer_head *bh, int uptodate)
{
        /* Decrypt if needed */
        if (uptodate && IS_ENABLED(CONFIG_FS_ENCRYPTION) &&
            IS_ENCRYPTED(bh->b_page->mapping->host) &&
            S_ISREG(bh->b_page->mapping->host->i_mode)) {
	...


This needs to be updated to use fscrypt_inode_uses_fs_layer_crypto() instead, so
that the filesystem-layer decryption is not done when the file is already using
inline decryption.

> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index f8578caba40d..aeaa01724d7c 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -1153,6 +1153,7 @@ struct ext4_inode_info {
>  #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
>  #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
>  #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
> +#define EXT4_MOUNT_INLINECRYPT		0x4000000 /* Inline encryption support */
>  #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
>  #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
>  #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 28f28de0c1b6..44d9651b8638 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -1090,7 +1090,7 @@ static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len,
>  	}
>  	if (unlikely(err)) {
>  		page_zero_new_buffers(page, from, to);
> -	} else if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) {
> +	} else if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
>  		for (i = 0; i < nr_wait; i++) {
>  			int err2;
>  
> @@ -3698,7 +3698,7 @@ static int __ext4_block_zero_page_range(handle_t *handle,
>  		/* Uhhuh. Read error. Complain and punt. */
>  		if (!buffer_uptodate(bh))
>  			goto unlock;
> -		if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) {
> +		if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
>  			/* We expect the key to be set. */
>  			BUG_ON(!fscrypt_has_encryption_key(inode));
>  			WARN_ON_ONCE(fscrypt_decrypt_pagecache_blocks(
> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
> index 24aeedb8fc75..acde754cc5ca 100644
> --- a/fs/ext4/page-io.c
> +++ b/fs/ext4/page-io.c
> @@ -404,6 +404,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
>  	 * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
>  	 */
>  	bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
> +	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
>  	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
>  	bio_set_dev(bio, bh->b_bdev);
>  	bio->bi_end_io = ext4_end_bio;
> @@ -420,7 +421,8 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
>  {
>  	int ret;
>  
> -	if (io->io_bio && bh->b_blocknr != io->io_next_block) {
> +	if (io->io_bio && (bh->b_blocknr != io->io_next_block ||
> +			   !fscrypt_mergeable_bio_bh(io->io_bio, bh))) {
>  submit_and_retry:
>  		ext4_io_submit(io);
>  	}
> @@ -508,7 +510,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
>  	 * (e.g. holes) to be unnecessarily encrypted, but this is rare and
>  	 * can't happen in the common case of blocksize == PAGE_SIZE.
>  	 */
> -	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode) && nr_to_submit) {
> +	if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) {
>  		gfp_t gfp_flags = GFP_NOFS;
>  		unsigned int enc_bytes = round_up(len, i_blocksize(inode));
>  
> diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
> index fef7755300c3..7844e27518b4 100644
> --- a/fs/ext4/readpage.c
> +++ b/fs/ext4/readpage.c
> @@ -183,7 +183,7 @@ static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode,
>  	unsigned int post_read_steps = 0;
>  	struct bio_post_read_ctx *ctx = NULL;
>  
> -	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
> +	if (fscrypt_inode_uses_fs_layer_crypto(inode))
>  		post_read_steps |= 1 << STEP_DECRYPT;
>  
>  	if (ext4_need_verity(inode, first_idx))
> @@ -220,6 +220,7 @@ int ext4_mpage_readpages(struct address_space *mapping,
>  	const unsigned blkbits = inode->i_blkbits;
>  	const unsigned blocks_per_page = PAGE_SIZE >> blkbits;
>  	const unsigned blocksize = 1 << blkbits;
> +	sector_t next_block;
>  	sector_t block_in_file;
>  	sector_t last_block;
>  	sector_t last_block_in_file;
> @@ -252,7 +253,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
>  		if (page_has_buffers(page))
>  			goto confused;
>  
> -		block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits);
> +		block_in_file = next_block =
> +			(sector_t)page->index << (PAGE_SHIFT - blkbits);
>  		last_block = block_in_file + nr_pages * blocks_per_page;
>  		last_block_in_file = (ext4_readpage_limit(inode) +
>  				      blocksize - 1) >> blkbits;
> @@ -352,7 +354,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
>  		 * This page will go to BIO.  Do we need to send this
>  		 * BIO off first?
>  		 */
> -		if (bio && (last_block_in_bio != blocks[0] - 1)) {
> +		if (bio && (last_block_in_bio != blocks[0] - 1 ||
> +			    !fscrypt_mergeable_bio(bio, inode, next_block))) {
>  		submit_and_realloc:
>  			submit_bio(bio);
>  			bio = NULL;
> @@ -366,6 +369,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
>  			 */
>  			bio = bio_alloc(GFP_KERNEL,
>  				min_t(int, nr_pages, BIO_MAX_PAGES));
> +			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
> +						  GFP_KERNEL);
>  			ctx = get_bio_post_read_ctx(inode, bio, page->index);
>  			if (IS_ERR(ctx)) {
>  				bio_put(bio);
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 1d82b56d9b11..0a6b60620942 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -1357,6 +1357,11 @@ static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
>  	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
>  }
>  
> +static bool ext4_inline_crypt_enabled(struct super_block *sb)
> +{
> +	return test_opt(sb, INLINECRYPT);
> +}
> +
>  static const struct fscrypt_operations ext4_cryptops = {
>  	.key_prefix		= "ext4:",
>  	.get_context		= ext4_get_context,
> @@ -1366,6 +1371,7 @@ static const struct fscrypt_operations ext4_cryptops = {
>  	.max_namelen		= EXT4_NAME_LEN,
>  	.has_stable_inodes	= ext4_has_stable_inodes,
>  	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
> +	.inline_crypt_enabled	= ext4_inline_crypt_enabled,
>  };
>  #endif
>  
> @@ -1460,6 +1466,7 @@ enum {
>  	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
>  	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
>  	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
> +	Opt_inlinecrypt,
>  	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
>  	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
>  	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
> @@ -1556,6 +1563,7 @@ static const match_table_t tokens = {
>  	{Opt_noinit_itable, "noinit_itable"},
>  	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
>  	{Opt_test_dummy_encryption, "test_dummy_encryption"},
> +	{Opt_inlinecrypt, "inlinecrypt"},
>  	{Opt_nombcache, "nombcache"},
>  	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
>  	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
> @@ -1767,6 +1775,11 @@ static const struct mount_opts {
>  	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
>  	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
>  	{Opt_test_dummy_encryption, 0, MOPT_GTE0},
> +#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
> +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_SET},
> +#else
> +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_NOSUPPORT},
> +#endif
>  	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
>  	{Opt_err, 0, 0}
>  };

On v5 there was a discussion about using a flag like SB_INLINECRYPT to replace
the ->inline_crypt_enabled() function.  Was this considered?

- Eric
Satya Tangirala Dec. 19, 2019, 12:31 a.m. UTC | #2
I messed up while using git and managed to overwrite the author field in
the patch - it should read "Eric Biggers <ebiggers@google.com>" instead.
I'll fix that in the next patch version, sorry.

On Wed, Dec 18, 2019 at 04:12:41PM -0800, Eric Biggers wrote:

> [+Cc linux-ext4]
> 
> On Wed, Dec 18, 2019 at 06:51:36AM -0800, Satya Tangirala wrote:
> > Wire up ext4 to support inline encryption via the helper functions which
> > fs/crypto/ now provides.  This includes:
> > 
> > - Adding a mount option 'inlinecrypt' which enables inline encryption
> >   on encrypted files where it can be used.
> > 
> > - Setting the bio_crypt_ctx on bios that will be submitted to an
> >   inline-encrypted file.
> > 
> >   Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for
> >   this part, since ext4 sometimes uses ll_rw_block() on file data.
> > 
> > - Not adding logically discontiguous data to bios that will be submitted
> >   to an inline-encrypted file.
> > 
> > - Not doing filesystem-layer crypto on inline-encrypted files.
> > 
> > Signed-off-by: Eric Biggers <ebiggers@google.com>
> > Signed-off-by: Satya Tangirala <satyat@google.com>
> 
> In the next version can you please add linux-ext4 to Cc for the series?
> 
Ok, I will.
> > ---
> >  fs/buffer.c        |  2 ++
> >  fs/ext4/ext4.h     |  1 +
> >  fs/ext4/inode.c    |  4 ++--
> >  fs/ext4/page-io.c  |  6 ++++--
> >  fs/ext4/readpage.c | 11 ++++++++---
> >  fs/ext4/super.c    | 13 +++++++++++++
> >  6 files changed, 30 insertions(+), 7 deletions(-)
> > 
> > diff --git a/fs/buffer.c b/fs/buffer.c
> > index d8c7242426bb..3ad000db4a19 100644
> > --- a/fs/buffer.c
> > +++ b/fs/buffer.c
> > @@ -3108,6 +3108,8 @@ static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
> >  	 */
> >  	bio = bio_alloc(GFP_NOIO, 1);
> >  
> > +	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
> > +
> >  	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
> >  	bio_set_dev(bio, bh->b_bdev);
> >  	bio->bi_write_hint = write_hint;
> 
> In 5.5, there was some decryption code added to fs/buffer.c in order to support
> ext4 encryption with blocksize < PAGE_SIZE:
> 
> static void end_buffer_async_read_io(struct buffer_head *bh, int uptodate)
> {
>         /* Decrypt if needed */
>         if (uptodate && IS_ENABLED(CONFIG_FS_ENCRYPTION) &&
>             IS_ENCRYPTED(bh->b_page->mapping->host) &&
>             S_ISREG(bh->b_page->mapping->host->i_mode)) {
> 	...
> 
> 
> This needs to be updated to use fscrypt_inode_uses_fs_layer_crypto() instead, so
> that the filesystem-layer decryption is not done when the file is already using
> inline decryption.
> 
Will fix in the next version.
> > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> > index f8578caba40d..aeaa01724d7c 100644
> > --- a/fs/ext4/ext4.h
> > +++ b/fs/ext4/ext4.h
> > @@ -1153,6 +1153,7 @@ struct ext4_inode_info {
> >  #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
> >  #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
> >  #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
> > +#define EXT4_MOUNT_INLINECRYPT		0x4000000 /* Inline encryption support */
> >  #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
> >  #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
> >  #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
> > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> > index 28f28de0c1b6..44d9651b8638 100644
> > --- a/fs/ext4/inode.c
> > +++ b/fs/ext4/inode.c
> > @@ -1090,7 +1090,7 @@ static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len,
> >  	}
> >  	if (unlikely(err)) {
> >  		page_zero_new_buffers(page, from, to);
> > -	} else if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) {
> > +	} else if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
> >  		for (i = 0; i < nr_wait; i++) {
> >  			int err2;
> >  
> > @@ -3698,7 +3698,7 @@ static int __ext4_block_zero_page_range(handle_t *handle,
> >  		/* Uhhuh. Read error. Complain and punt. */
> >  		if (!buffer_uptodate(bh))
> >  			goto unlock;
> > -		if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) {
> > +		if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
> >  			/* We expect the key to be set. */
> >  			BUG_ON(!fscrypt_has_encryption_key(inode));
> >  			WARN_ON_ONCE(fscrypt_decrypt_pagecache_blocks(
> > diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
> > index 24aeedb8fc75..acde754cc5ca 100644
> > --- a/fs/ext4/page-io.c
> > +++ b/fs/ext4/page-io.c
> > @@ -404,6 +404,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
> >  	 * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
> >  	 */
> >  	bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
> > +	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
> >  	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
> >  	bio_set_dev(bio, bh->b_bdev);
> >  	bio->bi_end_io = ext4_end_bio;
> > @@ -420,7 +421,8 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
> >  {
> >  	int ret;
> >  
> > -	if (io->io_bio && bh->b_blocknr != io->io_next_block) {
> > +	if (io->io_bio && (bh->b_blocknr != io->io_next_block ||
> > +			   !fscrypt_mergeable_bio_bh(io->io_bio, bh))) {
> >  submit_and_retry:
> >  		ext4_io_submit(io);
> >  	}
> > @@ -508,7 +510,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
> >  	 * (e.g. holes) to be unnecessarily encrypted, but this is rare and
> >  	 * can't happen in the common case of blocksize == PAGE_SIZE.
> >  	 */
> > -	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode) && nr_to_submit) {
> > +	if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) {
> >  		gfp_t gfp_flags = GFP_NOFS;
> >  		unsigned int enc_bytes = round_up(len, i_blocksize(inode));
> >  
> > diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
> > index fef7755300c3..7844e27518b4 100644
> > --- a/fs/ext4/readpage.c
> > +++ b/fs/ext4/readpage.c
> > @@ -183,7 +183,7 @@ static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode,
> >  	unsigned int post_read_steps = 0;
> >  	struct bio_post_read_ctx *ctx = NULL;
> >  
> > -	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
> > +	if (fscrypt_inode_uses_fs_layer_crypto(inode))
> >  		post_read_steps |= 1 << STEP_DECRYPT;
> >  
> >  	if (ext4_need_verity(inode, first_idx))
> > @@ -220,6 +220,7 @@ int ext4_mpage_readpages(struct address_space *mapping,
> >  	const unsigned blkbits = inode->i_blkbits;
> >  	const unsigned blocks_per_page = PAGE_SIZE >> blkbits;
> >  	const unsigned blocksize = 1 << blkbits;
> > +	sector_t next_block;
> >  	sector_t block_in_file;
> >  	sector_t last_block;
> >  	sector_t last_block_in_file;
> > @@ -252,7 +253,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
> >  		if (page_has_buffers(page))
> >  			goto confused;
> >  
> > -		block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits);
> > +		block_in_file = next_block =
> > +			(sector_t)page->index << (PAGE_SHIFT - blkbits);
> >  		last_block = block_in_file + nr_pages * blocks_per_page;
> >  		last_block_in_file = (ext4_readpage_limit(inode) +
> >  				      blocksize - 1) >> blkbits;
> > @@ -352,7 +354,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
> >  		 * This page will go to BIO.  Do we need to send this
> >  		 * BIO off first?
> >  		 */
> > -		if (bio && (last_block_in_bio != blocks[0] - 1)) {
> > +		if (bio && (last_block_in_bio != blocks[0] - 1 ||
> > +			    !fscrypt_mergeable_bio(bio, inode, next_block))) {
> >  		submit_and_realloc:
> >  			submit_bio(bio);
> >  			bio = NULL;
> > @@ -366,6 +369,8 @@ int ext4_mpage_readpages(struct address_space *mapping,
> >  			 */
> >  			bio = bio_alloc(GFP_KERNEL,
> >  				min_t(int, nr_pages, BIO_MAX_PAGES));
> > +			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
> > +						  GFP_KERNEL);
> >  			ctx = get_bio_post_read_ctx(inode, bio, page->index);
> >  			if (IS_ERR(ctx)) {
> >  				bio_put(bio);
> > diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> > index 1d82b56d9b11..0a6b60620942 100644
> > --- a/fs/ext4/super.c
> > +++ b/fs/ext4/super.c
> > @@ -1357,6 +1357,11 @@ static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
> >  	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
> >  }
> >  
> > +static bool ext4_inline_crypt_enabled(struct super_block *sb)
> > +{
> > +	return test_opt(sb, INLINECRYPT);
> > +}
> > +
> >  static const struct fscrypt_operations ext4_cryptops = {
> >  	.key_prefix		= "ext4:",
> >  	.get_context		= ext4_get_context,
> > @@ -1366,6 +1371,7 @@ static const struct fscrypt_operations ext4_cryptops = {
> >  	.max_namelen		= EXT4_NAME_LEN,
> >  	.has_stable_inodes	= ext4_has_stable_inodes,
> >  	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
> > +	.inline_crypt_enabled	= ext4_inline_crypt_enabled,
> >  };
> >  #endif
> >  
> > @@ -1460,6 +1466,7 @@ enum {
> >  	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
> >  	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
> >  	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
> > +	Opt_inlinecrypt,
> >  	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
> >  	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
> >  	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
> > @@ -1556,6 +1563,7 @@ static const match_table_t tokens = {
> >  	{Opt_noinit_itable, "noinit_itable"},
> >  	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
> >  	{Opt_test_dummy_encryption, "test_dummy_encryption"},
> > +	{Opt_inlinecrypt, "inlinecrypt"},
> >  	{Opt_nombcache, "nombcache"},
> >  	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
> >  	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
> > @@ -1767,6 +1775,11 @@ static const struct mount_opts {
> >  	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
> >  	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
> >  	{Opt_test_dummy_encryption, 0, MOPT_GTE0},
> > +#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
> > +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_SET},
> > +#else
> > +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_NOSUPPORT},
> > +#endif
> >  	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
> >  	{Opt_err, 0, 0}
> >  };
> 
> On v5 there was a discussion about using a flag like SB_INLINECRYPT to replace
> the ->inline_crypt_enabled() function.  Was this considered?
> 
Right, I'll add this change to the next version too.
> - Eric
Eric Biggers Dec. 22, 2019, 12:16 a.m. UTC | #3
On Wed, Dec 18, 2019 at 06:51:36AM -0800, Satya Tangirala wrote:
> @@ -1460,6 +1466,7 @@ enum {
>  	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
>  	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
>  	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
> +	Opt_inlinecrypt,
>  	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
>  	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
>  	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
> @@ -1556,6 +1563,7 @@ static const match_table_t tokens = {
>  	{Opt_noinit_itable, "noinit_itable"},
>  	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
>  	{Opt_test_dummy_encryption, "test_dummy_encryption"},
> +	{Opt_inlinecrypt, "inlinecrypt"},
>  	{Opt_nombcache, "nombcache"},
>  	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
>  	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
> @@ -1767,6 +1775,11 @@ static const struct mount_opts {
>  	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
>  	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
>  	{Opt_test_dummy_encryption, 0, MOPT_GTE0},
> +#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
> +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_SET},
> +#else
> +	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_NOSUPPORT},
> +#endif
>  	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
>  	{Opt_err, 0, 0}
>  };

This mount option will need to be documented in
Documentation/admin-guide/ext4.rst for ext4 and
Documentation/filesystems/f2fs.txt for f2fs.

- Eric
diff mbox series

Patch

diff --git a/fs/buffer.c b/fs/buffer.c
index d8c7242426bb..3ad000db4a19 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -3108,6 +3108,8 @@  static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh,
 	 */
 	bio = bio_alloc(GFP_NOIO, 1);
 
+	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
+
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 	bio_set_dev(bio, bh->b_bdev);
 	bio->bi_write_hint = write_hint;
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index f8578caba40d..aeaa01724d7c 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1153,6 +1153,7 @@  struct ext4_inode_info {
 #define EXT4_MOUNT_JOURNAL_CHECKSUM	0x800000 /* Journal checksums */
 #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async Commit */
 #define EXT4_MOUNT_WARN_ON_ERROR	0x2000000 /* Trigger WARN_ON on error */
+#define EXT4_MOUNT_INLINECRYPT		0x4000000 /* Inline encryption support */
 #define EXT4_MOUNT_DELALLOC		0x8000000 /* Delalloc support */
 #define EXT4_MOUNT_DATA_ERR_ABORT	0x10000000 /* Abort on file data write */
 #define EXT4_MOUNT_BLOCK_VALIDITY	0x20000000 /* Block validity checking */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 28f28de0c1b6..44d9651b8638 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1090,7 +1090,7 @@  static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len,
 	}
 	if (unlikely(err)) {
 		page_zero_new_buffers(page, from, to);
-	} else if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) {
+	} else if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
 		for (i = 0; i < nr_wait; i++) {
 			int err2;
 
@@ -3698,7 +3698,7 @@  static int __ext4_block_zero_page_range(handle_t *handle,
 		/* Uhhuh. Read error. Complain and punt. */
 		if (!buffer_uptodate(bh))
 			goto unlock;
-		if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) {
+		if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
 			/* We expect the key to be set. */
 			BUG_ON(!fscrypt_has_encryption_key(inode));
 			WARN_ON_ONCE(fscrypt_decrypt_pagecache_blocks(
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 24aeedb8fc75..acde754cc5ca 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -404,6 +404,7 @@  static void io_submit_init_bio(struct ext4_io_submit *io,
 	 * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
 	 */
 	bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
+	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 	bio_set_dev(bio, bh->b_bdev);
 	bio->bi_end_io = ext4_end_bio;
@@ -420,7 +421,8 @@  static void io_submit_add_bh(struct ext4_io_submit *io,
 {
 	int ret;
 
-	if (io->io_bio && bh->b_blocknr != io->io_next_block) {
+	if (io->io_bio && (bh->b_blocknr != io->io_next_block ||
+			   !fscrypt_mergeable_bio_bh(io->io_bio, bh))) {
 submit_and_retry:
 		ext4_io_submit(io);
 	}
@@ -508,7 +510,7 @@  int ext4_bio_write_page(struct ext4_io_submit *io,
 	 * (e.g. holes) to be unnecessarily encrypted, but this is rare and
 	 * can't happen in the common case of blocksize == PAGE_SIZE.
 	 */
-	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode) && nr_to_submit) {
+	if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) {
 		gfp_t gfp_flags = GFP_NOFS;
 		unsigned int enc_bytes = round_up(len, i_blocksize(inode));
 
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index fef7755300c3..7844e27518b4 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -183,7 +183,7 @@  static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode,
 	unsigned int post_read_steps = 0;
 	struct bio_post_read_ctx *ctx = NULL;
 
-	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
+	if (fscrypt_inode_uses_fs_layer_crypto(inode))
 		post_read_steps |= 1 << STEP_DECRYPT;
 
 	if (ext4_need_verity(inode, first_idx))
@@ -220,6 +220,7 @@  int ext4_mpage_readpages(struct address_space *mapping,
 	const unsigned blkbits = inode->i_blkbits;
 	const unsigned blocks_per_page = PAGE_SIZE >> blkbits;
 	const unsigned blocksize = 1 << blkbits;
+	sector_t next_block;
 	sector_t block_in_file;
 	sector_t last_block;
 	sector_t last_block_in_file;
@@ -252,7 +253,8 @@  int ext4_mpage_readpages(struct address_space *mapping,
 		if (page_has_buffers(page))
 			goto confused;
 
-		block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits);
+		block_in_file = next_block =
+			(sector_t)page->index << (PAGE_SHIFT - blkbits);
 		last_block = block_in_file + nr_pages * blocks_per_page;
 		last_block_in_file = (ext4_readpage_limit(inode) +
 				      blocksize - 1) >> blkbits;
@@ -352,7 +354,8 @@  int ext4_mpage_readpages(struct address_space *mapping,
 		 * This page will go to BIO.  Do we need to send this
 		 * BIO off first?
 		 */
-		if (bio && (last_block_in_bio != blocks[0] - 1)) {
+		if (bio && (last_block_in_bio != blocks[0] - 1 ||
+			    !fscrypt_mergeable_bio(bio, inode, next_block))) {
 		submit_and_realloc:
 			submit_bio(bio);
 			bio = NULL;
@@ -366,6 +369,8 @@  int ext4_mpage_readpages(struct address_space *mapping,
 			 */
 			bio = bio_alloc(GFP_KERNEL,
 				min_t(int, nr_pages, BIO_MAX_PAGES));
+			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
+						  GFP_KERNEL);
 			ctx = get_bio_post_read_ctx(inode, bio, page->index);
 			if (IS_ERR(ctx)) {
 				bio_put(bio);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 1d82b56d9b11..0a6b60620942 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1357,6 +1357,11 @@  static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
 }
 
+static bool ext4_inline_crypt_enabled(struct super_block *sb)
+{
+	return test_opt(sb, INLINECRYPT);
+}
+
 static const struct fscrypt_operations ext4_cryptops = {
 	.key_prefix		= "ext4:",
 	.get_context		= ext4_get_context,
@@ -1366,6 +1371,7 @@  static const struct fscrypt_operations ext4_cryptops = {
 	.max_namelen		= EXT4_NAME_LEN,
 	.has_stable_inodes	= ext4_has_stable_inodes,
 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
+	.inline_crypt_enabled	= ext4_inline_crypt_enabled,
 };
 #endif
 
@@ -1460,6 +1466,7 @@  enum {
 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
+	Opt_inlinecrypt,
 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
@@ -1556,6 +1563,7 @@  static const match_table_t tokens = {
 	{Opt_noinit_itable, "noinit_itable"},
 	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
 	{Opt_test_dummy_encryption, "test_dummy_encryption"},
+	{Opt_inlinecrypt, "inlinecrypt"},
 	{Opt_nombcache, "nombcache"},
 	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
 	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
@@ -1767,6 +1775,11 @@  static const struct mount_opts {
 	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
 	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
 	{Opt_test_dummy_encryption, 0, MOPT_GTE0},
+#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
+	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_SET},
+#else
+	{Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_NOSUPPORT},
+#endif
 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
 	{Opt_err, 0, 0}
 };