diff mbox

ext4 crypto: migrate into vfs's crypto engine

Message ID 1461629736-16523-1-git-send-email-jaegeuk@kernel.org
State Superseded, archived
Headers show

Commit Message

Jaegeuk Kim April 26, 2016, 12:15 a.m. UTC
This patch removes the most parts of internal crypto codes.
And then, it modifies and adds some ext4-specific crypt codes to use the generic
facility.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/ext4/Kconfig         |  12 +-
 fs/ext4/Makefile        |   2 -
 fs/ext4/crypto.c        | 536 ------------------------------------------------
 fs/ext4/crypto_fname.c  | 468 ------------------------------------------
 fs/ext4/crypto_key.c    | 274 -------------------------
 fs/ext4/crypto_policy.c | 229 ---------------------
 fs/ext4/dir.c           |  26 +--
 fs/ext4/ext4.h          | 197 ++++++------------
 fs/ext4/ext4_crypto.h   | 159 --------------
 fs/ext4/file.c          |  10 +-
 fs/ext4/ialloc.c        |   7 +-
 fs/ext4/inline.c        |  14 +-
 fs/ext4/inode.c         |   8 +-
 fs/ext4/ioctl.c         |  20 +-
 fs/ext4/namei.c         | 120 +++++------
 fs/ext4/page-io.c       |  13 +-
 fs/ext4/readpage.c      |  45 +---
 fs/ext4/super.c         |  85 +++++++-
 fs/ext4/symlink.c       |  33 ++-
 19 files changed, 271 insertions(+), 1987 deletions(-)
 delete mode 100644 fs/ext4/crypto.c
 delete mode 100644 fs/ext4/crypto_fname.c
 delete mode 100644 fs/ext4/crypto_key.c
 delete mode 100644 fs/ext4/crypto_policy.c
 delete mode 100644 fs/ext4/ext4_crypto.h

Comments

Theodore Ts'o May 5, 2016, 3:20 a.m. UTC | #1
On Mon, Apr 25, 2016 at 05:15:36PM -0700, Jaegeuk Kim wrote:
> This patch removes the most parts of internal crypto codes.
> And then, it modifies and adds some ext4-specific crypt codes to use the generic
> facility.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

So I just tried this patch, and one big problem with it is that it
breaks backwards compatibility with existing userspace code, which
assumes that the name of the keys are prefixed with "ext4:".  I see
that in fs/crypto.h you've changed it to be "fscrypto:".  Which is
more general, perhaps, but the problem is that it's not what the
existing shipping code (for example, in the Android N preview release)
and what e2fsprogs's e4crypto is using.

If we want to use fscrypto: as a more general prefix, I could see
doing that, but we need to provide for backwards compatibility ---
which means that at least for ext4, we will need to look for keys
using both the new and old prefix, and we would also want change
e4crypto to set keys with both the "ext4" and the more general
"fscrypto" prefix.

Cheers,

					- Ted
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Jaegeuk Kim May 5, 2016, 4:22 a.m. UTC | #2
On Wed, May 04, 2016 at 11:20:22PM -0400, Theodore Ts'o wrote:
> On Mon, Apr 25, 2016 at 05:15:36PM -0700, Jaegeuk Kim wrote:
> > This patch removes the most parts of internal crypto codes.
> > And then, it modifies and adds some ext4-specific crypt codes to use the generic
> > facility.
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> 
> So I just tried this patch, and one big problem with it is that it
> breaks backwards compatibility with existing userspace code, which
> assumes that the name of the keys are prefixed with "ext4:".  I see
> that in fs/crypto.h you've changed it to be "fscrypto:".  Which is
> more general, perhaps, but the problem is that it's not what the
> existing shipping code (for example, in the Android N preview release)
> and what e2fsprogs's e4crypto is using.

I also worried about that before, but I thought there was no shipped
fs_encryption-enabled product.
Actually, f2fs has the same issue as well, since "f2fs:" was used before. :(

> If we want to use fscrypto: as a more general prefix, I could see
> doing that, but we need to provide for backwards compatibility ---
> which means that at least for ext4, we will need to look for keys
> using both the new and old prefix, and we would also want change
> e4crypto to set keys with both the "ext4" and the more general
> "fscrypto" prefix.

Got it. Let me add (*key_prefix(inode)) in fscrypt_operations so that filesystem
can give a specific prefix additionally.
Once fscrypto supports both of prefixes, does e4crypto have to set "fscrypto"?
The "ext4" should work all the time tho.

Thanks,

> 
> Cheers,
> 
> 					- Ted
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Theodore Ts'o May 5, 2016, 12:44 p.m. UTC | #3
On Wed, May 04, 2016 at 09:22:48PM -0700, Jaegeuk Kim wrote:
> 
> Got it. Let me add (*key_prefix(inode)) in fscrypt_operations so that filesystem
> can give a specific prefix additionally.
> Once fscrypto supports both of prefixes, does e4crypto have to set "fscrypto"?
> The "ext4" should work all the time tho.

Well, the question is what userspace tool should be used for the
non-Android case?

The other thing to consider is the cost of doing lookups in two
keyrings all of the time.  I'm not sure how much overhead there is,
but if it's significant, it might be time to hang a keyring off the
superblock, and to start migrating to a model where keys are globally
available to the file system once they get their (either implicitly
because they are on a user's keyring, or explicitly via a new ioctl),
and when they are removed (either implicitly because a key has been
invalidated, or explicitly via a new ioctl), when a key gets added or
removed from the file system global keyring, we bump a sequence
counter so we can invalidate negative or positve dcache entries as
appropriate.

This goes back to the problem where the page and dentry caches are
global and the using per-user or per-session keyrings doesn't map
cleanly to the page and dentry caches.

						- Ted
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Eric Biggers May 7, 2016, 2:31 a.m. UTC | #4
Hi Jaegeuk,

On Mon, Apr 25, 2016 at 05:15:36PM -0700, Jaegeuk Kim wrote:
> This patch removes the most parts of internal crypto codes.
> And then, it modifies and adds some ext4-specific crypt codes to use the generic
> facility.

Except for the key name prefix issue that Ted pointed out, this overall seems
good, although I didn't read into every detail and haven't yet tested the code.
A few comments:

There are compiler errors and warnings in the function 'dx_show_leaf()', which
is not compiled by default.

In ext4_lookup():
>               /*
>                * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is
>                * created while the directory was encrypted and we
>                * don't have access to the key.
>                */
>               if (fscrypt_has_encryption_key(dir))
>                       fscrypt_set_encrypted_dentry(dentry);

Shouldn't this say "and we have access to the key"?  Or is the code wrong?

In ext4_empty_dir():
>       bool err = false;

Since this is a bool it should not be called "err".  Maybe call it "empty"
instead.

In ext4_finish_bio():
>               if (!page->mapping) {
>                       /* The bounce data pages are unmapped. */
>                       data_page = page;
>                       fscrypt_pullback_bio_page(&page, false);
>               }
...
>#ifdef CONFIG_EXT4_FS_ENCRYPTION
>                       if (data_page)
>                               fscrypt_restore_control_page(data_page);
>#endif

Does this always do the same thing as the previous code?  Does !page->mapping
always imply that the page was involved in encrypted I/O?

In ext4_encrypted_get_link():
>       if ((cstr.len + 
>            sizeof(struct fscrypt_symlink_data) - 1) >
>           max_size) {

Make this one line?

In ext4_file_mmap()
>               int err = fscrypt_get_encryption_info(inode);
>               if (err)
>                       return 0;

Should the error code be propagated to the caller?

In ext4_ioctl():
>       case EXT4_IOC_GET_ENCRYPTION_POLICY: {
>#ifdef CONFIG_EXT4_FS_ENCRYPTION
>               struct fscrypt_policy policy;
>               int err = 0;
>
>               if (!ext4_encrypted_inode(inode))
>                       return -ENOENT;

This is existing code and I do not know if it can be changed, but I feel that
ENOENT is a not good error code here.  If the ext4_encrypted_inode() check were
to be removed, the implementation would match f2fs and the error code would be
ENODATA instead.

- Eric
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Jaegeuk Kim May 7, 2016, 6:46 p.m. UTC | #5
Hi Eric,

Thank you for the review.

On Fri, May 06, 2016 at 09:31:02PM -0500, Eric Biggers wrote:
> Hi Jaegeuk,
> 
> On Mon, Apr 25, 2016 at 05:15:36PM -0700, Jaegeuk Kim wrote:
> > This patch removes the most parts of internal crypto codes.
> > And then, it modifies and adds some ext4-specific crypt codes to use the generic
> > facility.
> 
> Except for the key name prefix issue that Ted pointed out, this overall seems
> good, although I didn't read into every detail and haven't yet tested the code.
> A few comments:
> 
> There are compiler errors and warnings in the function 'dx_show_leaf()', which
> is not compiled by default.

Fixed.

> 
> In ext4_lookup():
> >               /*
> >                * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is
> >                * created while the directory was encrypted and we
> >                * don't have access to the key.
> >                */
> >               if (fscrypt_has_encryption_key(dir))
> >                       fscrypt_set_encrypted_dentry(dentry);
> 
> Shouldn't this say "and we have access to the key"?  Or is the code wrong?

Done.

> 
> In ext4_empty_dir():
> >       bool err = false;
> 
> Since this is a bool it should not be called "err".  Maybe call it "empty"
> instead.

Removed and worked around it.

> 
> In ext4_finish_bio():
> >               if (!page->mapping) {
> >                       /* The bounce data pages are unmapped. */
> >                       data_page = page;
> >                       fscrypt_pullback_bio_page(&page, false);
> >               }
> ...
> >#ifdef CONFIG_EXT4_FS_ENCRYPTION
> >                       if (data_page)
> >                               fscrypt_restore_control_page(data_page);
> >#endif
> 
> Does this always do the same thing as the previous code?  Does !page->mapping
> always imply that the page was involved in encrypted I/O?

I think so.

> 
> In ext4_encrypted_get_link():
> >       if ((cstr.len + 
> >            sizeof(struct fscrypt_symlink_data) - 1) >
> >           max_size) {
> 
> Make this one line?

Done.

> 
> In ext4_file_mmap()
> >               int err = fscrypt_get_encryption_info(inode);
> >               if (err)
> >                       return 0;
> 
> Should the error code be propagated to the caller?

This patch tries to keep existing flow as much as possible.

> 
> In ext4_ioctl():
> >       case EXT4_IOC_GET_ENCRYPTION_POLICY: {
> >#ifdef CONFIG_EXT4_FS_ENCRYPTION
> >               struct fscrypt_policy policy;
> >               int err = 0;
> >
> >               if (!ext4_encrypted_inode(inode))
> >                       return -ENOENT;
> 
> This is existing code and I do not know if it can be changed, but I feel that
> ENOENT is a not good error code here.  If the ext4_encrypted_inode() check were
> to be removed, the implementation would match f2fs and the error code would be
> ENODATA instead.

ditto.

> 
> - Eric
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diff mbox

Patch

diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index b46e9fc..e38039f 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -99,17 +99,9 @@  config EXT4_FS_SECURITY
 	  extended attributes for file security labels, say N.
 
 config EXT4_ENCRYPTION
-	tristate "Ext4 Encryption"
+	bool "Ext4 Encryption"
 	depends on EXT4_FS
-	select CRYPTO_AES
-	select CRYPTO_CBC
-	select CRYPTO_ECB
-	select CRYPTO_XTS
-	select CRYPTO_CTS
-	select CRYPTO_CTR
-	select CRYPTO_SHA256
-	select KEYS
-	select ENCRYPTED_KEYS
+	select FS_ENCRYPTION
 	help
 	  Enable encryption of ext4 files and directories.  This
 	  feature is similar to ecryptfs, but it is more memory
diff --git a/fs/ext4/Makefile b/fs/ext4/Makefile
index f52cf54..354103f 100644
--- a/fs/ext4/Makefile
+++ b/fs/ext4/Makefile
@@ -12,5 +12,3 @@  ext4-y	:= balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o page-io.o \
 
 ext4-$(CONFIG_EXT4_FS_POSIX_ACL)	+= acl.o
 ext4-$(CONFIG_EXT4_FS_SECURITY)		+= xattr_security.o
-ext4-$(CONFIG_EXT4_FS_ENCRYPTION)	+= crypto_policy.o crypto.o \
-		crypto_key.o crypto_fname.o
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
deleted file mode 100644
index 6a6c273..0000000
--- a/fs/ext4/crypto.c
+++ /dev/null
@@ -1,536 +0,0 @@ 
-/*
- * linux/fs/ext4/crypto.c
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains encryption functions for ext4
- *
- * Written by Michael Halcrow, 2014.
- *
- * Filename encryption additions
- *	Uday Savagaonkar, 2014
- * Encryption policy handling additions
- *	Ildar Muslukhov, 2014
- *
- * This has not yet undergone a rigorous security audit.
- *
- * The usage of AES-XTS should conform to recommendations in NIST
- * Special Publication 800-38E and IEEE P1619/D16.
- */
-
-#include <crypto/skcipher.h>
-#include <keys/user-type.h>
-#include <keys/encrypted-type.h>
-#include <linux/ecryptfs.h>
-#include <linux/gfp.h>
-#include <linux/kernel.h>
-#include <linux/key.h>
-#include <linux/list.h>
-#include <linux/mempool.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/random.h>
-#include <linux/scatterlist.h>
-#include <linux/spinlock_types.h>
-#include <linux/namei.h>
-
-#include "ext4_extents.h"
-#include "xattr.h"
-
-/* Encryption added and removed here! (L: */
-
-static unsigned int num_prealloc_crypto_pages = 32;
-static unsigned int num_prealloc_crypto_ctxs = 128;
-
-module_param(num_prealloc_crypto_pages, uint, 0444);
-MODULE_PARM_DESC(num_prealloc_crypto_pages,
-		 "Number of crypto pages to preallocate");
-module_param(num_prealloc_crypto_ctxs, uint, 0444);
-MODULE_PARM_DESC(num_prealloc_crypto_ctxs,
-		 "Number of crypto contexts to preallocate");
-
-static mempool_t *ext4_bounce_page_pool;
-
-static LIST_HEAD(ext4_free_crypto_ctxs);
-static DEFINE_SPINLOCK(ext4_crypto_ctx_lock);
-
-static struct kmem_cache *ext4_crypto_ctx_cachep;
-struct kmem_cache *ext4_crypt_info_cachep;
-
-/**
- * ext4_release_crypto_ctx() - Releases an encryption context
- * @ctx: The encryption context to release.
- *
- * If the encryption context was allocated from the pre-allocated pool, returns
- * it to that pool. Else, frees it.
- *
- * If there's a bounce page in the context, this frees that.
- */
-void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx)
-{
-	unsigned long flags;
-
-	if (ctx->flags & EXT4_WRITE_PATH_FL && ctx->w.bounce_page)
-		mempool_free(ctx->w.bounce_page, ext4_bounce_page_pool);
-	ctx->w.bounce_page = NULL;
-	ctx->w.control_page = NULL;
-	if (ctx->flags & EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL) {
-		kmem_cache_free(ext4_crypto_ctx_cachep, ctx);
-	} else {
-		spin_lock_irqsave(&ext4_crypto_ctx_lock, flags);
-		list_add(&ctx->free_list, &ext4_free_crypto_ctxs);
-		spin_unlock_irqrestore(&ext4_crypto_ctx_lock, flags);
-	}
-}
-
-/**
- * ext4_get_crypto_ctx() - Gets an encryption context
- * @inode:       The inode for which we are doing the crypto
- *
- * Allocates and initializes an encryption context.
- *
- * Return: An allocated and initialized encryption context on success; error
- * value or NULL otherwise.
- */
-struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode,
-					    gfp_t gfp_flags)
-{
-	struct ext4_crypto_ctx *ctx = NULL;
-	int res = 0;
-	unsigned long flags;
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-
-	if (ci == NULL)
-		return ERR_PTR(-ENOKEY);
-
-	/*
-	 * We first try getting the ctx from a free list because in
-	 * the common case the ctx will have an allocated and
-	 * initialized crypto tfm, so it's probably a worthwhile
-	 * optimization. For the bounce page, we first try getting it
-	 * from the kernel allocator because that's just about as fast
-	 * as getting it from a list and because a cache of free pages
-	 * should generally be a "last resort" option for a filesystem
-	 * to be able to do its job.
-	 */
-	spin_lock_irqsave(&ext4_crypto_ctx_lock, flags);
-	ctx = list_first_entry_or_null(&ext4_free_crypto_ctxs,
-				       struct ext4_crypto_ctx, free_list);
-	if (ctx)
-		list_del(&ctx->free_list);
-	spin_unlock_irqrestore(&ext4_crypto_ctx_lock, flags);
-	if (!ctx) {
-		ctx = kmem_cache_zalloc(ext4_crypto_ctx_cachep, gfp_flags);
-		if (!ctx) {
-			res = -ENOMEM;
-			goto out;
-		}
-		ctx->flags |= EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL;
-	} else {
-		ctx->flags &= ~EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL;
-	}
-	ctx->flags &= ~EXT4_WRITE_PATH_FL;
-
-out:
-	if (res) {
-		if (!IS_ERR_OR_NULL(ctx))
-			ext4_release_crypto_ctx(ctx);
-		ctx = ERR_PTR(res);
-	}
-	return ctx;
-}
-
-struct workqueue_struct *ext4_read_workqueue;
-static DEFINE_MUTEX(crypto_init);
-
-/**
- * ext4_exit_crypto() - Shutdown the ext4 encryption system
- */
-void ext4_exit_crypto(void)
-{
-	struct ext4_crypto_ctx *pos, *n;
-
-	list_for_each_entry_safe(pos, n, &ext4_free_crypto_ctxs, free_list)
-		kmem_cache_free(ext4_crypto_ctx_cachep, pos);
-	INIT_LIST_HEAD(&ext4_free_crypto_ctxs);
-	if (ext4_bounce_page_pool)
-		mempool_destroy(ext4_bounce_page_pool);
-	ext4_bounce_page_pool = NULL;
-	if (ext4_read_workqueue)
-		destroy_workqueue(ext4_read_workqueue);
-	ext4_read_workqueue = NULL;
-	if (ext4_crypto_ctx_cachep)
-		kmem_cache_destroy(ext4_crypto_ctx_cachep);
-	ext4_crypto_ctx_cachep = NULL;
-	if (ext4_crypt_info_cachep)
-		kmem_cache_destroy(ext4_crypt_info_cachep);
-	ext4_crypt_info_cachep = NULL;
-}
-
-/**
- * ext4_init_crypto() - Set up for ext4 encryption.
- *
- * We only call this when we start accessing encrypted files, since it
- * results in memory getting allocated that wouldn't otherwise be used.
- *
- * Return: Zero on success, non-zero otherwise.
- */
-int ext4_init_crypto(void)
-{
-	int i, res = -ENOMEM;
-
-	mutex_lock(&crypto_init);
-	if (ext4_read_workqueue)
-		goto already_initialized;
-	ext4_read_workqueue = alloc_workqueue("ext4_crypto", WQ_HIGHPRI, 0);
-	if (!ext4_read_workqueue)
-		goto fail;
-
-	ext4_crypto_ctx_cachep = KMEM_CACHE(ext4_crypto_ctx,
-					    SLAB_RECLAIM_ACCOUNT);
-	if (!ext4_crypto_ctx_cachep)
-		goto fail;
-
-	ext4_crypt_info_cachep = KMEM_CACHE(ext4_crypt_info,
-					    SLAB_RECLAIM_ACCOUNT);
-	if (!ext4_crypt_info_cachep)
-		goto fail;
-
-	for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
-		struct ext4_crypto_ctx *ctx;
-
-		ctx = kmem_cache_zalloc(ext4_crypto_ctx_cachep, GFP_NOFS);
-		if (!ctx) {
-			res = -ENOMEM;
-			goto fail;
-		}
-		list_add(&ctx->free_list, &ext4_free_crypto_ctxs);
-	}
-
-	ext4_bounce_page_pool =
-		mempool_create_page_pool(num_prealloc_crypto_pages, 0);
-	if (!ext4_bounce_page_pool) {
-		res = -ENOMEM;
-		goto fail;
-	}
-already_initialized:
-	mutex_unlock(&crypto_init);
-	return 0;
-fail:
-	ext4_exit_crypto();
-	mutex_unlock(&crypto_init);
-	return res;
-}
-
-void ext4_restore_control_page(struct page *data_page)
-{
-	struct ext4_crypto_ctx *ctx =
-		(struct ext4_crypto_ctx *)page_private(data_page);
-
-	set_page_private(data_page, (unsigned long)NULL);
-	ClearPagePrivate(data_page);
-	unlock_page(data_page);
-	ext4_release_crypto_ctx(ctx);
-}
-
-/**
- * ext4_crypt_complete() - The completion callback for page encryption
- * @req: The asynchronous encryption request context
- * @res: The result of the encryption operation
- */
-static void ext4_crypt_complete(struct crypto_async_request *req, int res)
-{
-	struct ext4_completion_result *ecr = req->data;
-
-	if (res == -EINPROGRESS)
-		return;
-	ecr->res = res;
-	complete(&ecr->completion);
-}
-
-typedef enum {
-	EXT4_DECRYPT = 0,
-	EXT4_ENCRYPT,
-} ext4_direction_t;
-
-static int ext4_page_crypto(struct inode *inode,
-			    ext4_direction_t rw,
-			    pgoff_t index,
-			    struct page *src_page,
-			    struct page *dest_page,
-			    gfp_t gfp_flags)
-
-{
-	u8 xts_tweak[EXT4_XTS_TWEAK_SIZE];
-	struct skcipher_request *req = NULL;
-	DECLARE_EXT4_COMPLETION_RESULT(ecr);
-	struct scatterlist dst, src;
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-	struct crypto_skcipher *tfm = ci->ci_ctfm;
-	int res = 0;
-
-	req = skcipher_request_alloc(tfm, gfp_flags);
-	if (!req) {
-		printk_ratelimited(KERN_ERR
-				   "%s: crypto_request_alloc() failed\n",
-				   __func__);
-		return -ENOMEM;
-	}
-	skcipher_request_set_callback(
-		req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
-		ext4_crypt_complete, &ecr);
-
-	BUILD_BUG_ON(EXT4_XTS_TWEAK_SIZE < sizeof(index));
-	memcpy(xts_tweak, &index, sizeof(index));
-	memset(&xts_tweak[sizeof(index)], 0,
-	       EXT4_XTS_TWEAK_SIZE - sizeof(index));
-
-	sg_init_table(&dst, 1);
-	sg_set_page(&dst, dest_page, PAGE_SIZE, 0);
-	sg_init_table(&src, 1);
-	sg_set_page(&src, src_page, PAGE_SIZE, 0);
-	skcipher_request_set_crypt(req, &src, &dst, PAGE_SIZE,
-				   xts_tweak);
-	if (rw == EXT4_DECRYPT)
-		res = crypto_skcipher_decrypt(req);
-	else
-		res = crypto_skcipher_encrypt(req);
-	if (res == -EINPROGRESS || res == -EBUSY) {
-		wait_for_completion(&ecr.completion);
-		res = ecr.res;
-	}
-	skcipher_request_free(req);
-	if (res) {
-		printk_ratelimited(
-			KERN_ERR
-			"%s: crypto_skcipher_encrypt() returned %d\n",
-			__func__, res);
-		return res;
-	}
-	return 0;
-}
-
-static struct page *alloc_bounce_page(struct ext4_crypto_ctx *ctx,
-				      gfp_t gfp_flags)
-{
-	ctx->w.bounce_page = mempool_alloc(ext4_bounce_page_pool, gfp_flags);
-	if (ctx->w.bounce_page == NULL)
-		return ERR_PTR(-ENOMEM);
-	ctx->flags |= EXT4_WRITE_PATH_FL;
-	return ctx->w.bounce_page;
-}
-
-/**
- * ext4_encrypt() - Encrypts a page
- * @inode:          The inode for which the encryption should take place
- * @plaintext_page: The page to encrypt. Must be locked.
- *
- * Allocates a ciphertext page and encrypts plaintext_page into it using the ctx
- * encryption context.
- *
- * Called on the page write path.  The caller must call
- * ext4_restore_control_page() on the returned ciphertext page to
- * release the bounce buffer and the encryption context.
- *
- * Return: An allocated page with the encrypted content on success. Else, an
- * error value or NULL.
- */
-struct page *ext4_encrypt(struct inode *inode,
-			  struct page *plaintext_page,
-			  gfp_t gfp_flags)
-{
-	struct ext4_crypto_ctx *ctx;
-	struct page *ciphertext_page = NULL;
-	int err;
-
-	BUG_ON(!PageLocked(plaintext_page));
-
-	ctx = ext4_get_crypto_ctx(inode, gfp_flags);
-	if (IS_ERR(ctx))
-		return (struct page *) ctx;
-
-	/* The encryption operation will require a bounce page. */
-	ciphertext_page = alloc_bounce_page(ctx, gfp_flags);
-	if (IS_ERR(ciphertext_page))
-		goto errout;
-	ctx->w.control_page = plaintext_page;
-	err = ext4_page_crypto(inode, EXT4_ENCRYPT, plaintext_page->index,
-			       plaintext_page, ciphertext_page, gfp_flags);
-	if (err) {
-		ciphertext_page = ERR_PTR(err);
-	errout:
-		ext4_release_crypto_ctx(ctx);
-		return ciphertext_page;
-	}
-	SetPagePrivate(ciphertext_page);
-	set_page_private(ciphertext_page, (unsigned long)ctx);
-	lock_page(ciphertext_page);
-	return ciphertext_page;
-}
-
-/**
- * ext4_decrypt() - Decrypts a page in-place
- * @ctx:  The encryption context.
- * @page: The page to decrypt. Must be locked.
- *
- * Decrypts page in-place using the ctx encryption context.
- *
- * Called from the read completion callback.
- *
- * Return: Zero on success, non-zero otherwise.
- */
-int ext4_decrypt(struct page *page)
-{
-	BUG_ON(!PageLocked(page));
-
-	return ext4_page_crypto(page->mapping->host, EXT4_DECRYPT,
-				page->index, page, page, GFP_NOFS);
-}
-
-int ext4_encrypted_zeroout(struct inode *inode, ext4_lblk_t lblk,
-			   ext4_fsblk_t pblk, ext4_lblk_t len)
-{
-	struct ext4_crypto_ctx	*ctx;
-	struct page		*ciphertext_page = NULL;
-	struct bio		*bio;
-	int			ret, err = 0;
-
-#if 0
-	ext4_msg(inode->i_sb, KERN_CRIT,
-		 "ext4_encrypted_zeroout ino %lu lblk %u len %u",
-		 (unsigned long) inode->i_ino, lblk, len);
-#endif
-
-	BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
-
-	ctx = ext4_get_crypto_ctx(inode, GFP_NOFS);
-	if (IS_ERR(ctx))
-		return PTR_ERR(ctx);
-
-	ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT);
-	if (IS_ERR(ciphertext_page)) {
-		err = PTR_ERR(ciphertext_page);
-		goto errout;
-	}
-
-	while (len--) {
-		err = ext4_page_crypto(inode, EXT4_ENCRYPT, lblk,
-				       ZERO_PAGE(0), ciphertext_page,
-				       GFP_NOFS);
-		if (err)
-			goto errout;
-
-		bio = bio_alloc(GFP_NOWAIT, 1);
-		if (!bio) {
-			err = -ENOMEM;
-			goto errout;
-		}
-		bio->bi_bdev = inode->i_sb->s_bdev;
-		bio->bi_iter.bi_sector =
-			pblk << (inode->i_sb->s_blocksize_bits - 9);
-		ret = bio_add_page(bio, ciphertext_page,
-				   inode->i_sb->s_blocksize, 0);
-		if (ret != inode->i_sb->s_blocksize) {
-			/* should never happen! */
-			ext4_msg(inode->i_sb, KERN_ERR,
-				 "bio_add_page failed: %d", ret);
-			WARN_ON(1);
-			bio_put(bio);
-			err = -EIO;
-			goto errout;
-		}
-		err = submit_bio_wait(WRITE, bio);
-		if ((err == 0) && bio->bi_error)
-			err = -EIO;
-		bio_put(bio);
-		if (err)
-			goto errout;
-		lblk++; pblk++;
-	}
-	err = 0;
-errout:
-	ext4_release_crypto_ctx(ctx);
-	return err;
-}
-
-bool ext4_valid_contents_enc_mode(uint32_t mode)
-{
-	return (mode == EXT4_ENCRYPTION_MODE_AES_256_XTS);
-}
-
-/**
- * ext4_validate_encryption_key_size() - Validate the encryption key size
- * @mode: The key mode.
- * @size: The key size to validate.
- *
- * Return: The validated key size for @mode. Zero if invalid.
- */
-uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size)
-{
-	if (size == ext4_encryption_key_size(mode))
-		return size;
-	return 0;
-}
-
-/*
- * Validate dentries for encrypted directories to make sure we aren't
- * potentially caching stale data after a key has been added or
- * removed.
- */
-static int ext4_d_revalidate(struct dentry *dentry, unsigned int flags)
-{
-	struct dentry *dir;
-	struct ext4_crypt_info *ci;
-	int dir_has_key, cached_with_key;
-
-	if (flags & LOOKUP_RCU)
-		return -ECHILD;
-
-	dir = dget_parent(dentry);
-	if (!ext4_encrypted_inode(d_inode(dir))) {
-		dput(dir);
-		return 0;
-	}
-	ci = EXT4_I(d_inode(dir))->i_crypt_info;
-	if (ci && ci->ci_keyring_key &&
-	    (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
-					  (1 << KEY_FLAG_REVOKED) |
-					  (1 << KEY_FLAG_DEAD))))
-		ci = NULL;
-
-	/* this should eventually be an flag in d_flags */
-	cached_with_key = dentry->d_fsdata != NULL;
-	dir_has_key = (ci != NULL);
-	dput(dir);
-
-	/*
-	 * If the dentry was cached without the key, and it is a
-	 * negative dentry, it might be a valid name.  We can't check
-	 * if the key has since been made available due to locking
-	 * reasons, so we fail the validation so ext4_lookup() can do
-	 * this check.
-	 *
-	 * We also fail the validation if the dentry was created with
-	 * the key present, but we no longer have the key, or vice versa.
-	 */
-	if ((!cached_with_key && d_is_negative(dentry)) ||
-	    (!cached_with_key && dir_has_key) ||
-	    (cached_with_key && !dir_has_key)) {
-#if 0				/* Revalidation debug */
-		char buf[80];
-		char *cp = simple_dname(dentry, buf, sizeof(buf));
-
-		if (IS_ERR(cp))
-			cp = (char *) "???";
-		pr_err("revalidate: %s %p %d %d %d\n", cp, dentry->d_fsdata,
-		       cached_with_key, d_is_negative(dentry),
-		       dir_has_key);
-#endif
-		return 0;
-	}
-	return 1;
-}
-
-const struct dentry_operations ext4_encrypted_d_ops = {
-	.d_revalidate = ext4_d_revalidate,
-};
diff --git a/fs/ext4/crypto_fname.c b/fs/ext4/crypto_fname.c
deleted file mode 100644
index 1a2f360..0000000
--- a/fs/ext4/crypto_fname.c
+++ /dev/null
@@ -1,468 +0,0 @@ 
-/*
- * linux/fs/ext4/crypto_fname.c
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains functions for filename crypto management in ext4
- *
- * Written by Uday Savagaonkar, 2014.
- *
- * This has not yet undergone a rigorous security audit.
- *
- */
-
-#include <crypto/skcipher.h>
-#include <keys/encrypted-type.h>
-#include <keys/user-type.h>
-#include <linux/gfp.h>
-#include <linux/kernel.h>
-#include <linux/key.h>
-#include <linux/list.h>
-#include <linux/mempool.h>
-#include <linux/random.h>
-#include <linux/scatterlist.h>
-#include <linux/spinlock_types.h>
-
-#include "ext4.h"
-#include "ext4_crypto.h"
-#include "xattr.h"
-
-/**
- * ext4_dir_crypt_complete() -
- */
-static void ext4_dir_crypt_complete(struct crypto_async_request *req, int res)
-{
-	struct ext4_completion_result *ecr = req->data;
-
-	if (res == -EINPROGRESS)
-		return;
-	ecr->res = res;
-	complete(&ecr->completion);
-}
-
-bool ext4_valid_filenames_enc_mode(uint32_t mode)
-{
-	return (mode == EXT4_ENCRYPTION_MODE_AES_256_CTS);
-}
-
-static unsigned max_name_len(struct inode *inode)
-{
-	return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
-		EXT4_NAME_LEN;
-}
-
-/**
- * ext4_fname_encrypt() -
- *
- * This function encrypts the input filename, and returns the length of the
- * ciphertext. Errors are returned as negative numbers.  We trust the caller to
- * allocate sufficient memory to oname string.
- */
-static int ext4_fname_encrypt(struct inode *inode,
-			      const struct qstr *iname,
-			      struct ext4_str *oname)
-{
-	u32 ciphertext_len;
-	struct skcipher_request *req = NULL;
-	DECLARE_EXT4_COMPLETION_RESULT(ecr);
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-	struct crypto_skcipher *tfm = ci->ci_ctfm;
-	int res = 0;
-	char iv[EXT4_CRYPTO_BLOCK_SIZE];
-	struct scatterlist src_sg, dst_sg;
-	int padding = 4 << (ci->ci_flags & EXT4_POLICY_FLAGS_PAD_MASK);
-	char *workbuf, buf[32], *alloc_buf = NULL;
-	unsigned lim = max_name_len(inode);
-
-	if (iname->len <= 0 || iname->len > lim)
-		return -EIO;
-
-	ciphertext_len = (iname->len < EXT4_CRYPTO_BLOCK_SIZE) ?
-		EXT4_CRYPTO_BLOCK_SIZE : iname->len;
-	ciphertext_len = ext4_fname_crypto_round_up(ciphertext_len, padding);
-	ciphertext_len = (ciphertext_len > lim)
-			? lim : ciphertext_len;
-
-	if (ciphertext_len <= sizeof(buf)) {
-		workbuf = buf;
-	} else {
-		alloc_buf = kmalloc(ciphertext_len, GFP_NOFS);
-		if (!alloc_buf)
-			return -ENOMEM;
-		workbuf = alloc_buf;
-	}
-
-	/* Allocate request */
-	req = skcipher_request_alloc(tfm, GFP_NOFS);
-	if (!req) {
-		printk_ratelimited(
-		    KERN_ERR "%s: crypto_request_alloc() failed\n", __func__);
-		kfree(alloc_buf);
-		return -ENOMEM;
-	}
-	skcipher_request_set_callback(req,
-		CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
-		ext4_dir_crypt_complete, &ecr);
-
-	/* Copy the input */
-	memcpy(workbuf, iname->name, iname->len);
-	if (iname->len < ciphertext_len)
-		memset(workbuf + iname->len, 0, ciphertext_len - iname->len);
-
-	/* Initialize IV */
-	memset(iv, 0, EXT4_CRYPTO_BLOCK_SIZE);
-
-	/* Create encryption request */
-	sg_init_one(&src_sg, workbuf, ciphertext_len);
-	sg_init_one(&dst_sg, oname->name, ciphertext_len);
-	skcipher_request_set_crypt(req, &src_sg, &dst_sg, ciphertext_len, iv);
-	res = crypto_skcipher_encrypt(req);
-	if (res == -EINPROGRESS || res == -EBUSY) {
-		wait_for_completion(&ecr.completion);
-		res = ecr.res;
-	}
-	kfree(alloc_buf);
-	skcipher_request_free(req);
-	if (res < 0) {
-		printk_ratelimited(
-		    KERN_ERR "%s: Error (error code %d)\n", __func__, res);
-	}
-	oname->len = ciphertext_len;
-	return res;
-}
-
-/*
- * ext4_fname_decrypt()
- *	This function decrypts the input filename, and returns
- *	the length of the plaintext.
- *	Errors are returned as negative numbers.
- *	We trust the caller to allocate sufficient memory to oname string.
- */
-static int ext4_fname_decrypt(struct inode *inode,
-			      const struct ext4_str *iname,
-			      struct ext4_str *oname)
-{
-	struct ext4_str tmp_in[2], tmp_out[1];
-	struct skcipher_request *req = NULL;
-	DECLARE_EXT4_COMPLETION_RESULT(ecr);
-	struct scatterlist src_sg, dst_sg;
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-	struct crypto_skcipher *tfm = ci->ci_ctfm;
-	int res = 0;
-	char iv[EXT4_CRYPTO_BLOCK_SIZE];
-	unsigned lim = max_name_len(inode);
-
-	if (iname->len <= 0 || iname->len > lim)
-		return -EIO;
-
-	tmp_in[0].name = iname->name;
-	tmp_in[0].len = iname->len;
-	tmp_out[0].name = oname->name;
-
-	/* Allocate request */
-	req = skcipher_request_alloc(tfm, GFP_NOFS);
-	if (!req) {
-		printk_ratelimited(
-		    KERN_ERR "%s: crypto_request_alloc() failed\n",  __func__);
-		return -ENOMEM;
-	}
-	skcipher_request_set_callback(req,
-		CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
-		ext4_dir_crypt_complete, &ecr);
-
-	/* Initialize IV */
-	memset(iv, 0, EXT4_CRYPTO_BLOCK_SIZE);
-
-	/* Create encryption request */
-	sg_init_one(&src_sg, iname->name, iname->len);
-	sg_init_one(&dst_sg, oname->name, oname->len);
-	skcipher_request_set_crypt(req, &src_sg, &dst_sg, iname->len, iv);
-	res = crypto_skcipher_decrypt(req);
-	if (res == -EINPROGRESS || res == -EBUSY) {
-		wait_for_completion(&ecr.completion);
-		res = ecr.res;
-	}
-	skcipher_request_free(req);
-	if (res < 0) {
-		printk_ratelimited(
-		    KERN_ERR "%s: Error in ext4_fname_encrypt (error code %d)\n",
-		    __func__, res);
-		return res;
-	}
-
-	oname->len = strnlen(oname->name, iname->len);
-	return oname->len;
-}
-
-static const char *lookup_table =
-	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,";
-
-/**
- * ext4_fname_encode_digest() -
- *
- * Encodes the input digest using characters from the set [a-zA-Z0-9_+].
- * The encoded string is roughly 4/3 times the size of the input string.
- */
-static int digest_encode(const char *src, int len, char *dst)
-{
-	int i = 0, bits = 0, ac = 0;
-	char *cp = dst;
-
-	while (i < len) {
-		ac += (((unsigned char) src[i]) << bits);
-		bits += 8;
-		do {
-			*cp++ = lookup_table[ac & 0x3f];
-			ac >>= 6;
-			bits -= 6;
-		} while (bits >= 6);
-		i++;
-	}
-	if (bits)
-		*cp++ = lookup_table[ac & 0x3f];
-	return cp - dst;
-}
-
-static int digest_decode(const char *src, int len, char *dst)
-{
-	int i = 0, bits = 0, ac = 0;
-	const char *p;
-	char *cp = dst;
-
-	while (i < len) {
-		p = strchr(lookup_table, src[i]);
-		if (p == NULL || src[i] == 0)
-			return -2;
-		ac += (p - lookup_table) << bits;
-		bits += 6;
-		if (bits >= 8) {
-			*cp++ = ac & 0xff;
-			ac >>= 8;
-			bits -= 8;
-		}
-		i++;
-	}
-	if (ac)
-		return -1;
-	return cp - dst;
-}
-
-/**
- * ext4_fname_crypto_round_up() -
- *
- * Return: The next multiple of block size
- */
-u32 ext4_fname_crypto_round_up(u32 size, u32 blksize)
-{
-	return ((size+blksize-1)/blksize)*blksize;
-}
-
-unsigned ext4_fname_encrypted_size(struct inode *inode, u32 ilen)
-{
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-	int padding = 32;
-
-	if (ci)
-		padding = 4 << (ci->ci_flags & EXT4_POLICY_FLAGS_PAD_MASK);
-	if (ilen < EXT4_CRYPTO_BLOCK_SIZE)
-		ilen = EXT4_CRYPTO_BLOCK_SIZE;
-	return ext4_fname_crypto_round_up(ilen, padding);
-}
-
-/*
- * ext4_fname_crypto_alloc_buffer() -
- *
- * Allocates an output buffer that is sufficient for the crypto operation
- * specified by the context and the direction.
- */
-int ext4_fname_crypto_alloc_buffer(struct inode *inode,
-				   u32 ilen, struct ext4_str *crypto_str)
-{
-	unsigned int olen = ext4_fname_encrypted_size(inode, ilen);
-
-	crypto_str->len = olen;
-	if (olen < EXT4_FNAME_CRYPTO_DIGEST_SIZE*2)
-		olen = EXT4_FNAME_CRYPTO_DIGEST_SIZE*2;
-	/* Allocated buffer can hold one more character to null-terminate the
-	 * string */
-	crypto_str->name = kmalloc(olen+1, GFP_NOFS);
-	if (!(crypto_str->name))
-		return -ENOMEM;
-	return 0;
-}
-
-/**
- * ext4_fname_crypto_free_buffer() -
- *
- * Frees the buffer allocated for crypto operation.
- */
-void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str)
-{
-	if (!crypto_str)
-		return;
-	kfree(crypto_str->name);
-	crypto_str->name = NULL;
-}
-
-/**
- * ext4_fname_disk_to_usr() - converts a filename from disk space to user space
- */
-int _ext4_fname_disk_to_usr(struct inode *inode,
-			    struct dx_hash_info *hinfo,
-			    const struct ext4_str *iname,
-			    struct ext4_str *oname)
-{
-	char buf[24];
-	int ret;
-
-	if (iname->len < 3) {
-		/*Check for . and .. */
-		if (iname->name[0] == '.' && iname->name[iname->len-1] == '.') {
-			oname->name[0] = '.';
-			oname->name[iname->len-1] = '.';
-			oname->len = iname->len;
-			return oname->len;
-		}
-	}
-	if (iname->len < EXT4_CRYPTO_BLOCK_SIZE) {
-		EXT4_ERROR_INODE(inode, "encrypted inode too small");
-		return -EUCLEAN;
-	}
-	if (EXT4_I(inode)->i_crypt_info)
-		return ext4_fname_decrypt(inode, iname, oname);
-
-	if (iname->len <= EXT4_FNAME_CRYPTO_DIGEST_SIZE) {
-		ret = digest_encode(iname->name, iname->len, oname->name);
-		oname->len = ret;
-		return ret;
-	}
-	if (hinfo) {
-		memcpy(buf, &hinfo->hash, 4);
-		memcpy(buf+4, &hinfo->minor_hash, 4);
-	} else
-		memset(buf, 0, 8);
-	memcpy(buf + 8, iname->name + iname->len - 16, 16);
-	oname->name[0] = '_';
-	ret = digest_encode(buf, 24, oname->name+1);
-	oname->len = ret + 1;
-	return ret + 1;
-}
-
-int ext4_fname_disk_to_usr(struct inode *inode,
-			   struct dx_hash_info *hinfo,
-			   const struct ext4_dir_entry_2 *de,
-			   struct ext4_str *oname)
-{
-	struct ext4_str iname = {.name = (unsigned char *) de->name,
-				 .len = de->name_len };
-
-	return _ext4_fname_disk_to_usr(inode, hinfo, &iname, oname);
-}
-
-
-/**
- * ext4_fname_usr_to_disk() - converts a filename from user space to disk space
- */
-int ext4_fname_usr_to_disk(struct inode *inode,
-			   const struct qstr *iname,
-			   struct ext4_str *oname)
-{
-	int res;
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-
-	if (iname->len < 3) {
-		/*Check for . and .. */
-		if (iname->name[0] == '.' &&
-				iname->name[iname->len-1] == '.') {
-			oname->name[0] = '.';
-			oname->name[iname->len-1] = '.';
-			oname->len = iname->len;
-			return oname->len;
-		}
-	}
-	if (ci) {
-		res = ext4_fname_encrypt(inode, iname, oname);
-		return res;
-	}
-	/* Without a proper key, a user is not allowed to modify the filenames
-	 * in a directory. Consequently, a user space name cannot be mapped to
-	 * a disk-space name */
-	return -EACCES;
-}
-
-int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
-			      int lookup, struct ext4_filename *fname)
-{
-	struct ext4_crypt_info *ci;
-	int ret = 0, bigname = 0;
-
-	memset(fname, 0, sizeof(struct ext4_filename));
-	fname->usr_fname = iname;
-
-	if (!ext4_encrypted_inode(dir) ||
-	    ((iname->name[0] == '.') &&
-	     ((iname->len == 1) ||
-	      ((iname->name[1] == '.') && (iname->len == 2))))) {
-		fname->disk_name.name = (unsigned char *) iname->name;
-		fname->disk_name.len = iname->len;
-		return 0;
-	}
-	ret = ext4_get_encryption_info(dir);
-	if (ret)
-		return ret;
-	ci = EXT4_I(dir)->i_crypt_info;
-	if (ci) {
-		ret = ext4_fname_crypto_alloc_buffer(dir, iname->len,
-						     &fname->crypto_buf);
-		if (ret < 0)
-			return ret;
-		ret = ext4_fname_encrypt(dir, iname, &fname->crypto_buf);
-		if (ret < 0)
-			goto errout;
-		fname->disk_name.name = fname->crypto_buf.name;
-		fname->disk_name.len = fname->crypto_buf.len;
-		return 0;
-	}
-	if (!lookup)
-		return -EACCES;
-
-	/* We don't have the key and we are doing a lookup; decode the
-	 * user-supplied name
-	 */
-	if (iname->name[0] == '_')
-		bigname = 1;
-	if ((bigname && (iname->len != 33)) ||
-	    (!bigname && (iname->len > 43)))
-		return -ENOENT;
-
-	fname->crypto_buf.name = kmalloc(32, GFP_KERNEL);
-	if (fname->crypto_buf.name == NULL)
-		return -ENOMEM;
-	ret = digest_decode(iname->name + bigname, iname->len - bigname,
-			    fname->crypto_buf.name);
-	if (ret < 0) {
-		ret = -ENOENT;
-		goto errout;
-	}
-	fname->crypto_buf.len = ret;
-	if (bigname) {
-		memcpy(&fname->hinfo.hash, fname->crypto_buf.name, 4);
-		memcpy(&fname->hinfo.minor_hash, fname->crypto_buf.name + 4, 4);
-	} else {
-		fname->disk_name.name = fname->crypto_buf.name;
-		fname->disk_name.len = fname->crypto_buf.len;
-	}
-	return 0;
-errout:
-	kfree(fname->crypto_buf.name);
-	fname->crypto_buf.name = NULL;
-	return ret;
-}
-
-void ext4_fname_free_filename(struct ext4_filename *fname)
-{
-	kfree(fname->crypto_buf.name);
-	fname->crypto_buf.name = NULL;
-	fname->usr_fname = NULL;
-	fname->disk_name.name = NULL;
-}
diff --git a/fs/ext4/crypto_key.c b/fs/ext4/crypto_key.c
deleted file mode 100644
index 0129d68..0000000
--- a/fs/ext4/crypto_key.c
+++ /dev/null
@@ -1,274 +0,0 @@ 
-/*
- * linux/fs/ext4/crypto_key.c
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains encryption key functions for ext4
- *
- * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
- */
-
-#include <crypto/skcipher.h>
-#include <keys/encrypted-type.h>
-#include <keys/user-type.h>
-#include <linux/random.h>
-#include <linux/scatterlist.h>
-#include <uapi/linux/keyctl.h>
-
-#include "ext4.h"
-#include "xattr.h"
-
-static void derive_crypt_complete(struct crypto_async_request *req, int rc)
-{
-	struct ext4_completion_result *ecr = req->data;
-
-	if (rc == -EINPROGRESS)
-		return;
-
-	ecr->res = rc;
-	complete(&ecr->completion);
-}
-
-/**
- * ext4_derive_key_aes() - Derive a key using AES-128-ECB
- * @deriving_key: Encryption key used for derivation.
- * @source_key:   Source key to which to apply derivation.
- * @derived_key:  Derived key.
- *
- * Return: Zero on success; non-zero otherwise.
- */
-static int ext4_derive_key_aes(char deriving_key[EXT4_AES_128_ECB_KEY_SIZE],
-			       char source_key[EXT4_AES_256_XTS_KEY_SIZE],
-			       char derived_key[EXT4_AES_256_XTS_KEY_SIZE])
-{
-	int res = 0;
-	struct skcipher_request *req = NULL;
-	DECLARE_EXT4_COMPLETION_RESULT(ecr);
-	struct scatterlist src_sg, dst_sg;
-	struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
-
-	if (IS_ERR(tfm)) {
-		res = PTR_ERR(tfm);
-		tfm = NULL;
-		goto out;
-	}
-	crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
-	req = skcipher_request_alloc(tfm, GFP_NOFS);
-	if (!req) {
-		res = -ENOMEM;
-		goto out;
-	}
-	skcipher_request_set_callback(req,
-			CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
-			derive_crypt_complete, &ecr);
-	res = crypto_skcipher_setkey(tfm, deriving_key,
-				     EXT4_AES_128_ECB_KEY_SIZE);
-	if (res < 0)
-		goto out;
-	sg_init_one(&src_sg, source_key, EXT4_AES_256_XTS_KEY_SIZE);
-	sg_init_one(&dst_sg, derived_key, EXT4_AES_256_XTS_KEY_SIZE);
-	skcipher_request_set_crypt(req, &src_sg, &dst_sg,
-				   EXT4_AES_256_XTS_KEY_SIZE, NULL);
-	res = crypto_skcipher_encrypt(req);
-	if (res == -EINPROGRESS || res == -EBUSY) {
-		wait_for_completion(&ecr.completion);
-		res = ecr.res;
-	}
-
-out:
-	skcipher_request_free(req);
-	crypto_free_skcipher(tfm);
-	return res;
-}
-
-void ext4_free_crypt_info(struct ext4_crypt_info *ci)
-{
-	if (!ci)
-		return;
-
-	if (ci->ci_keyring_key)
-		key_put(ci->ci_keyring_key);
-	crypto_free_skcipher(ci->ci_ctfm);
-	kmem_cache_free(ext4_crypt_info_cachep, ci);
-}
-
-void ext4_free_encryption_info(struct inode *inode,
-			       struct ext4_crypt_info *ci)
-{
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_crypt_info *prev;
-
-	if (ci == NULL)
-		ci = ACCESS_ONCE(ei->i_crypt_info);
-	if (ci == NULL)
-		return;
-	prev = cmpxchg(&ei->i_crypt_info, ci, NULL);
-	if (prev != ci)
-		return;
-
-	ext4_free_crypt_info(ci);
-}
-
-int _ext4_get_encryption_info(struct inode *inode)
-{
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_crypt_info *crypt_info;
-	char full_key_descriptor[EXT4_KEY_DESC_PREFIX_SIZE +
-				 (EXT4_KEY_DESCRIPTOR_SIZE * 2) + 1];
-	struct key *keyring_key = NULL;
-	struct ext4_encryption_key *master_key;
-	struct ext4_encryption_context ctx;
-	const struct user_key_payload *ukp;
-	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
-	struct crypto_skcipher *ctfm;
-	const char *cipher_str;
-	char raw_key[EXT4_MAX_KEY_SIZE];
-	char mode;
-	int res;
-
-	if (!ext4_read_workqueue) {
-		res = ext4_init_crypto();
-		if (res)
-			return res;
-	}
-
-retry:
-	crypt_info = ACCESS_ONCE(ei->i_crypt_info);
-	if (crypt_info) {
-		if (!crypt_info->ci_keyring_key ||
-		    key_validate(crypt_info->ci_keyring_key) == 0)
-			return 0;
-		ext4_free_encryption_info(inode, crypt_info);
-		goto retry;
-	}
-
-	res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
-				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
-				 &ctx, sizeof(ctx));
-	if (res < 0) {
-		if (!DUMMY_ENCRYPTION_ENABLED(sbi))
-			return res;
-		ctx.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
-		ctx.filenames_encryption_mode =
-			EXT4_ENCRYPTION_MODE_AES_256_CTS;
-		ctx.flags = 0;
-	} else if (res != sizeof(ctx))
-		return -EINVAL;
-	res = 0;
-
-	crypt_info = kmem_cache_alloc(ext4_crypt_info_cachep, GFP_KERNEL);
-	if (!crypt_info)
-		return -ENOMEM;
-
-	crypt_info->ci_flags = ctx.flags;
-	crypt_info->ci_data_mode = ctx.contents_encryption_mode;
-	crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
-	crypt_info->ci_ctfm = NULL;
-	crypt_info->ci_keyring_key = NULL;
-	memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
-	       sizeof(crypt_info->ci_master_key));
-	if (S_ISREG(inode->i_mode))
-		mode = crypt_info->ci_data_mode;
-	else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
-		mode = crypt_info->ci_filename_mode;
-	else
-		BUG();
-	switch (mode) {
-	case EXT4_ENCRYPTION_MODE_AES_256_XTS:
-		cipher_str = "xts(aes)";
-		break;
-	case EXT4_ENCRYPTION_MODE_AES_256_CTS:
-		cipher_str = "cts(cbc(aes))";
-		break;
-	default:
-		printk_once(KERN_WARNING
-			    "ext4: unsupported key mode %d (ino %u)\n",
-			    mode, (unsigned) inode->i_ino);
-		res = -ENOKEY;
-		goto out;
-	}
-	if (DUMMY_ENCRYPTION_ENABLED(sbi)) {
-		memset(raw_key, 0x42, EXT4_AES_256_XTS_KEY_SIZE);
-		goto got_key;
-	}
-	memcpy(full_key_descriptor, EXT4_KEY_DESC_PREFIX,
-	       EXT4_KEY_DESC_PREFIX_SIZE);
-	sprintf(full_key_descriptor + EXT4_KEY_DESC_PREFIX_SIZE,
-		"%*phN", EXT4_KEY_DESCRIPTOR_SIZE,
-		ctx.master_key_descriptor);
-	full_key_descriptor[EXT4_KEY_DESC_PREFIX_SIZE +
-			    (2 * EXT4_KEY_DESCRIPTOR_SIZE)] = '\0';
-	keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
-	if (IS_ERR(keyring_key)) {
-		res = PTR_ERR(keyring_key);
-		keyring_key = NULL;
-		goto out;
-	}
-	crypt_info->ci_keyring_key = keyring_key;
-	if (keyring_key->type != &key_type_logon) {
-		printk_once(KERN_WARNING
-			    "ext4: key type must be logon\n");
-		res = -ENOKEY;
-		goto out;
-	}
-	down_read(&keyring_key->sem);
-	ukp = user_key_payload(keyring_key);
-	if (ukp->datalen != sizeof(struct ext4_encryption_key)) {
-		res = -EINVAL;
-		up_read(&keyring_key->sem);
-		goto out;
-	}
-	master_key = (struct ext4_encryption_key *)ukp->data;
-	BUILD_BUG_ON(EXT4_AES_128_ECB_KEY_SIZE !=
-		     EXT4_KEY_DERIVATION_NONCE_SIZE);
-	if (master_key->size != EXT4_AES_256_XTS_KEY_SIZE) {
-		printk_once(KERN_WARNING
-			    "ext4: key size incorrect: %d\n",
-			    master_key->size);
-		res = -ENOKEY;
-		up_read(&keyring_key->sem);
-		goto out;
-	}
-	res = ext4_derive_key_aes(ctx.nonce, master_key->raw,
-				  raw_key);
-	up_read(&keyring_key->sem);
-	if (res)
-		goto out;
-got_key:
-	ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
-	if (!ctfm || IS_ERR(ctfm)) {
-		res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
-		printk(KERN_DEBUG
-		       "%s: error %d (inode %u) allocating crypto tfm\n",
-		       __func__, res, (unsigned) inode->i_ino);
-		goto out;
-	}
-	crypt_info->ci_ctfm = ctfm;
-	crypto_skcipher_clear_flags(ctfm, ~0);
-	crypto_tfm_set_flags(crypto_skcipher_tfm(ctfm),
-			     CRYPTO_TFM_REQ_WEAK_KEY);
-	res = crypto_skcipher_setkey(ctfm, raw_key,
-				     ext4_encryption_key_size(mode));
-	if (res)
-		goto out;
-	memzero_explicit(raw_key, sizeof(raw_key));
-	if (cmpxchg(&ei->i_crypt_info, NULL, crypt_info) != NULL) {
-		ext4_free_crypt_info(crypt_info);
-		goto retry;
-	}
-	return 0;
-
-out:
-	if (res == -ENOKEY)
-		res = 0;
-	ext4_free_crypt_info(crypt_info);
-	memzero_explicit(raw_key, sizeof(raw_key));
-	return res;
-}
-
-int ext4_has_encryption_key(struct inode *inode)
-{
-	struct ext4_inode_info *ei = EXT4_I(inode);
-
-	return (ei->i_crypt_info != NULL);
-}
diff --git a/fs/ext4/crypto_policy.c b/fs/ext4/crypto_policy.c
deleted file mode 100644
index ad05069..0000000
--- a/fs/ext4/crypto_policy.c
+++ /dev/null
@@ -1,229 +0,0 @@ 
-/*
- * linux/fs/ext4/crypto_policy.c
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains encryption policy functions for ext4
- *
- * Written by Michael Halcrow, 2015.
- */
-
-#include <linux/random.h>
-#include <linux/string.h>
-#include <linux/types.h>
-
-#include "ext4_jbd2.h"
-#include "ext4.h"
-#include "xattr.h"
-
-static int ext4_inode_has_encryption_context(struct inode *inode)
-{
-	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
-				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, NULL, 0);
-	return (res > 0);
-}
-
-/*
- * check whether the policy is consistent with the encryption context
- * for the inode
- */
-static int ext4_is_encryption_context_consistent_with_policy(
-	struct inode *inode, const struct ext4_encryption_policy *policy)
-{
-	struct ext4_encryption_context ctx;
-	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
-				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
-				 sizeof(ctx));
-	if (res != sizeof(ctx))
-		return 0;
-	return (memcmp(ctx.master_key_descriptor, policy->master_key_descriptor,
-			EXT4_KEY_DESCRIPTOR_SIZE) == 0 &&
-		(ctx.flags ==
-		 policy->flags) &&
-		(ctx.contents_encryption_mode ==
-		 policy->contents_encryption_mode) &&
-		(ctx.filenames_encryption_mode ==
-		 policy->filenames_encryption_mode));
-}
-
-static int ext4_create_encryption_context_from_policy(
-	struct inode *inode, const struct ext4_encryption_policy *policy)
-{
-	struct ext4_encryption_context ctx;
-	handle_t *handle;
-	int res, res2;
-
-	res = ext4_convert_inline_data(inode);
-	if (res)
-		return res;
-
-	ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
-	memcpy(ctx.master_key_descriptor, policy->master_key_descriptor,
-	       EXT4_KEY_DESCRIPTOR_SIZE);
-	if (!ext4_valid_contents_enc_mode(policy->contents_encryption_mode)) {
-		printk(KERN_WARNING
-		       "%s: Invalid contents encryption mode %d\n", __func__,
-			policy->contents_encryption_mode);
-		return -EINVAL;
-	}
-	if (!ext4_valid_filenames_enc_mode(policy->filenames_encryption_mode)) {
-		printk(KERN_WARNING
-		       "%s: Invalid filenames encryption mode %d\n", __func__,
-			policy->filenames_encryption_mode);
-		return -EINVAL;
-	}
-	if (policy->flags & ~EXT4_POLICY_FLAGS_VALID)
-		return -EINVAL;
-	ctx.contents_encryption_mode = policy->contents_encryption_mode;
-	ctx.filenames_encryption_mode = policy->filenames_encryption_mode;
-	ctx.flags = policy->flags;
-	BUILD_BUG_ON(sizeof(ctx.nonce) != EXT4_KEY_DERIVATION_NONCE_SIZE);
-	get_random_bytes(ctx.nonce, EXT4_KEY_DERIVATION_NONCE_SIZE);
-
-	handle = ext4_journal_start(inode, EXT4_HT_MISC,
-				    ext4_jbd2_credits_xattr(inode));
-	if (IS_ERR(handle))
-		return PTR_ERR(handle);
-	res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
-			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
-			     sizeof(ctx), 0);
-	if (!res) {
-		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
-		res = ext4_mark_inode_dirty(handle, inode);
-		if (res)
-			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
-	}
-	res2 = ext4_journal_stop(handle);
-	if (!res)
-		res = res2;
-	return res;
-}
-
-int ext4_process_policy(const struct ext4_encryption_policy *policy,
-			struct inode *inode)
-{
-	if (policy->version != 0)
-		return -EINVAL;
-
-	if (!ext4_inode_has_encryption_context(inode)) {
-		if (!S_ISDIR(inode->i_mode))
-			return -EINVAL;
-		if (!ext4_empty_dir(inode))
-			return -ENOTEMPTY;
-		return ext4_create_encryption_context_from_policy(inode,
-								  policy);
-	}
-
-	if (ext4_is_encryption_context_consistent_with_policy(inode, policy))
-		return 0;
-
-	printk(KERN_WARNING "%s: Policy inconsistent with encryption context\n",
-	       __func__);
-	return -EINVAL;
-}
-
-int ext4_get_policy(struct inode *inode, struct ext4_encryption_policy *policy)
-{
-	struct ext4_encryption_context ctx;
-
-	int res = ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
-				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
-				 &ctx, sizeof(ctx));
-	if (res != sizeof(ctx))
-		return -ENOENT;
-	if (ctx.format != EXT4_ENCRYPTION_CONTEXT_FORMAT_V1)
-		return -EINVAL;
-	policy->version = 0;
-	policy->contents_encryption_mode = ctx.contents_encryption_mode;
-	policy->filenames_encryption_mode = ctx.filenames_encryption_mode;
-	policy->flags = ctx.flags;
-	memcpy(&policy->master_key_descriptor, ctx.master_key_descriptor,
-	       EXT4_KEY_DESCRIPTOR_SIZE);
-	return 0;
-}
-
-int ext4_is_child_context_consistent_with_parent(struct inode *parent,
-						 struct inode *child)
-{
-	struct ext4_crypt_info *parent_ci, *child_ci;
-	int res;
-
-	if ((parent == NULL) || (child == NULL)) {
-		pr_err("parent %p child %p\n", parent, child);
-		WARN_ON(1);	/* Should never happen */
-		return 0;
-	}
-	/* no restrictions if the parent directory is not encrypted */
-	if (!ext4_encrypted_inode(parent))
-		return 1;
-	/* if the child directory is not encrypted, this is always a problem */
-	if (!ext4_encrypted_inode(child))
-		return 0;
-	res = ext4_get_encryption_info(parent);
-	if (res)
-		return 0;
-	res = ext4_get_encryption_info(child);
-	if (res)
-		return 0;
-	parent_ci = EXT4_I(parent)->i_crypt_info;
-	child_ci = EXT4_I(child)->i_crypt_info;
-	if (!parent_ci && !child_ci)
-		return 1;
-	if (!parent_ci || !child_ci)
-		return 0;
-
-	return (memcmp(parent_ci->ci_master_key,
-		       child_ci->ci_master_key,
-		       EXT4_KEY_DESCRIPTOR_SIZE) == 0 &&
-		(parent_ci->ci_data_mode == child_ci->ci_data_mode) &&
-		(parent_ci->ci_filename_mode == child_ci->ci_filename_mode) &&
-		(parent_ci->ci_flags == child_ci->ci_flags));
-}
-
-/**
- * ext4_inherit_context() - Sets a child context from its parent
- * @parent: Parent inode from which the context is inherited.
- * @child:  Child inode that inherits the context from @parent.
- *
- * Return: Zero on success, non-zero otherwise
- */
-int ext4_inherit_context(struct inode *parent, struct inode *child)
-{
-	struct ext4_encryption_context ctx;
-	struct ext4_crypt_info *ci;
-	int res;
-
-	res = ext4_get_encryption_info(parent);
-	if (res < 0)
-		return res;
-	ci = EXT4_I(parent)->i_crypt_info;
-	if (ci == NULL)
-		return -ENOKEY;
-
-	ctx.format = EXT4_ENCRYPTION_CONTEXT_FORMAT_V1;
-	if (DUMMY_ENCRYPTION_ENABLED(EXT4_SB(parent->i_sb))) {
-		ctx.contents_encryption_mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
-		ctx.filenames_encryption_mode =
-			EXT4_ENCRYPTION_MODE_AES_256_CTS;
-		ctx.flags = 0;
-		memset(ctx.master_key_descriptor, 0x42,
-		       EXT4_KEY_DESCRIPTOR_SIZE);
-		res = 0;
-	} else {
-		ctx.contents_encryption_mode = ci->ci_data_mode;
-		ctx.filenames_encryption_mode = ci->ci_filename_mode;
-		ctx.flags = ci->ci_flags;
-		memcpy(ctx.master_key_descriptor, ci->ci_master_key,
-		       EXT4_KEY_DESCRIPTOR_SIZE);
-	}
-	get_random_bytes(ctx.nonce, EXT4_KEY_DERIVATION_NONCE_SIZE);
-	res = ext4_xattr_set(child, EXT4_XATTR_INDEX_ENCRYPTION,
-			     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
-			     sizeof(ctx), 0);
-	if (!res) {
-		ext4_set_inode_flag(child, EXT4_INODE_ENCRYPT);
-		ext4_clear_inode_state(child, EXT4_STATE_MAY_INLINE_DATA);
-		res = ext4_get_encryption_info(child);
-	}
-	return res;
-}
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 561d730..301f189 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -109,10 +109,10 @@  static int ext4_readdir(struct file *file, struct dir_context *ctx)
 	struct super_block *sb = inode->i_sb;
 	struct buffer_head *bh = NULL;
 	int dir_has_error = 0;
-	struct ext4_str fname_crypto_str = {.name = NULL, .len = 0};
+	struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
 
 	if (ext4_encrypted_inode(inode)) {
-		err = ext4_get_encryption_info(inode);
+		err = fscrypt_get_encryption_info(inode);
 		if (err && err != -ENOKEY)
 			return err;
 	}
@@ -139,8 +139,7 @@  static int ext4_readdir(struct file *file, struct dir_context *ctx)
 	}
 
 	if (ext4_encrypted_inode(inode)) {
-		err = ext4_fname_crypto_alloc_buffer(inode, EXT4_NAME_LEN,
-						     &fname_crypto_str);
+		err = fscrypt_fname_alloc_buffer(inode, EXT4_NAME_LEN, &fstr);
 		if (err < 0)
 			return err;
 	}
@@ -248,16 +247,19 @@  static int ext4_readdir(struct file *file, struct dir_context *ctx)
 					    get_dtype(sb, de->file_type)))
 						goto done;
 				} else {
-					int save_len = fname_crypto_str.len;
+					int save_len = fstr.len;
+					struct fscrypt_str de_name =
+							FSTR_INIT(de->name,
+								de->name_len);
 
 					/* Directory is encrypted */
-					err = ext4_fname_disk_to_usr(inode,
-						NULL, de, &fname_crypto_str);
-					fname_crypto_str.len = save_len;
+					err = fscrypt_fname_disk_to_usr(inode,
+						0, 0, &de_name, &fstr);
+					fstr.len = save_len;
 					if (err < 0)
 						goto errout;
 					if (!dir_emit(ctx,
-					    fname_crypto_str.name, err,
+					    fstr.name, err,
 					    le32_to_cpu(de->inode),
 					    get_dtype(sb, de->file_type)))
 						goto done;
@@ -276,7 +278,7 @@  done:
 	err = 0;
 errout:
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-	ext4_fname_crypto_free_buffer(&fname_crypto_str);
+	fscrypt_fname_free_buffer(&fstr);
 #endif
 	brelse(bh);
 	return err;
@@ -427,7 +429,7 @@  void ext4_htree_free_dir_info(struct dir_private_info *p)
 int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
 			     __u32 minor_hash,
 			    struct ext4_dir_entry_2 *dirent,
-			    struct ext4_str *ent_name)
+			    struct fscrypt_str *ent_name)
 {
 	struct rb_node **p, *parent = NULL;
 	struct fname *fname, *new_fn;
@@ -604,7 +606,7 @@  finished:
 static int ext4_dir_open(struct inode * inode, struct file * filp)
 {
 	if (ext4_encrypted_inode(inode))
-		return ext4_get_encryption_info(inode) ? -EACCES : 0;
+		return fscrypt_get_encryption_info(inode) ? -EACCES : 0;
 	return 0;
 }
 
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 349afeb..3b92225 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -32,6 +32,7 @@ 
 #include <linux/percpu_counter.h>
 #include <linux/ratelimit.h>
 #include <crypto/hash.h>
+#include <linux/fscrypto.h>
 #include <linux/falloc.h>
 #ifdef __KERNEL__
 #include <linux/compat.h>
@@ -604,15 +605,6 @@  enum {
 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER	0x0010
 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER	0x0020
 
-/* Encryption algorithms */
-#define EXT4_ENCRYPTION_MODE_INVALID		0
-#define EXT4_ENCRYPTION_MODE_AES_256_XTS	1
-#define EXT4_ENCRYPTION_MODE_AES_256_GCM	2
-#define EXT4_ENCRYPTION_MODE_AES_256_CBC	3
-#define EXT4_ENCRYPTION_MODE_AES_256_CTS	4
-
-#include "ext4_crypto.h"
-
 /*
  * ioctl commands
  */
@@ -634,9 +626,9 @@  enum {
 #define EXT4_IOC_RESIZE_FS		_IOW('f', 16, __u64)
 #define EXT4_IOC_SWAP_BOOT		_IO('f', 17)
 #define EXT4_IOC_PRECACHE_EXTENTS	_IO('f', 18)
-#define EXT4_IOC_SET_ENCRYPTION_POLICY	_IOR('f', 19, struct ext4_encryption_policy)
-#define EXT4_IOC_GET_ENCRYPTION_PWSALT	_IOW('f', 20, __u8[16])
-#define EXT4_IOC_GET_ENCRYPTION_POLICY	_IOW('f', 21, struct ext4_encryption_policy)
+#define EXT4_IOC_SET_ENCRYPTION_POLICY	FS_IOC_SET_ENCRYPTION_POLICY
+#define EXT4_IOC_GET_ENCRYPTION_PWSALT	FS_IOC_GET_ENCRYPTION_PWSALT
+#define EXT4_IOC_GET_ENCRYPTION_POLICY	FS_IOC_GET_ENCRYPTION_POLICY
 
 #ifndef FS_IOC_FSGETXATTR
 /* Until the uapi changes get merged for project quota... */
@@ -1078,10 +1070,6 @@  struct ext4_inode_info {
 	/* Precomputed uuid+inum+igen checksum for seeding inode checksums */
 	__u32 i_csum_seed;
 
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	/* Encryption params */
-	struct ext4_crypt_info *i_crypt_info;
-#endif
 	kprojid_t i_projid;
 };
 
@@ -1604,15 +1592,6 @@  static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
 /*
  * Returns true if the inode is inode is encrypted
  */
-static inline int ext4_encrypted_inode(struct inode *inode)
-{
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
-#else
-	return 0;
-#endif
-}
-
 #define NEXT_ORPHAN(inode) EXT4_I(inode)->i_dtime
 
 /*
@@ -2076,10 +2055,10 @@  struct dx_hash_info
 
 struct ext4_filename {
 	const struct qstr *usr_fname;
-	struct ext4_str disk_name;
+	struct fscrypt_str disk_name;
 	struct dx_hash_info hinfo;
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-	struct ext4_str crypto_buf;
+	struct fscrypt_str crypto_buf;
 #endif
 };
 
@@ -2290,132 +2269,82 @@  extern unsigned ext4_free_clusters_after_init(struct super_block *sb,
 					      struct ext4_group_desc *gdp);
 ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
 
-/* crypto_policy.c */
-int ext4_is_child_context_consistent_with_parent(struct inode *parent,
-						 struct inode *child);
-int ext4_inherit_context(struct inode *parent, struct inode *child);
-void ext4_to_hex(char *dst, char *src, size_t src_size);
-int ext4_process_policy(const struct ext4_encryption_policy *policy,
-			struct inode *inode);
-int ext4_get_policy(struct inode *inode,
-		    struct ext4_encryption_policy *policy);
-
-/* crypto.c */
-extern struct kmem_cache *ext4_crypt_info_cachep;
-bool ext4_valid_contents_enc_mode(uint32_t mode);
-uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size);
-extern struct workqueue_struct *ext4_read_workqueue;
-struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode,
-					    gfp_t gfp_flags);
-void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx);
-void ext4_restore_control_page(struct page *data_page);
-struct page *ext4_encrypt(struct inode *inode,
-			  struct page *plaintext_page,
-			  gfp_t gfp_flags);
-int ext4_decrypt(struct page *page);
-int ext4_encrypted_zeroout(struct inode *inode, ext4_lblk_t lblk,
-			   ext4_fsblk_t pblk, ext4_lblk_t len);
-extern const struct dentry_operations ext4_encrypted_d_ops;
-
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-int ext4_init_crypto(void);
-void ext4_exit_crypto(void);
 static inline int ext4_sb_has_crypto(struct super_block *sb)
 {
 	return ext4_has_feature_encrypt(sb);
 }
-#else
-static inline int ext4_init_crypto(void) { return 0; }
-static inline void ext4_exit_crypto(void) { }
-static inline int ext4_sb_has_crypto(struct super_block *sb)
+
+static inline bool ext4_encrypted_inode(struct inode *inode)
 {
-	return 0;
+	return ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT);
 }
-#endif
 
-/* crypto_fname.c */
-bool ext4_valid_filenames_enc_mode(uint32_t mode);
-u32 ext4_fname_crypto_round_up(u32 size, u32 blksize);
-unsigned ext4_fname_encrypted_size(struct inode *inode, u32 ilen);
-int ext4_fname_crypto_alloc_buffer(struct inode *inode,
-				   u32 ilen, struct ext4_str *crypto_str);
-int _ext4_fname_disk_to_usr(struct inode *inode,
-			    struct dx_hash_info *hinfo,
-			    const struct ext4_str *iname,
-			    struct ext4_str *oname);
-int ext4_fname_disk_to_usr(struct inode *inode,
-			   struct dx_hash_info *hinfo,
-			   const struct ext4_dir_entry_2 *de,
-			   struct ext4_str *oname);
-int ext4_fname_usr_to_disk(struct inode *inode,
-			   const struct qstr *iname,
-			   struct ext4_str *oname);
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-void ext4_fname_crypto_free_buffer(struct ext4_str *crypto_str);
-int ext4_fname_setup_filename(struct inode *dir, const struct qstr *iname,
-			      int lookup, struct ext4_filename *fname);
-void ext4_fname_free_filename(struct ext4_filename *fname);
-#else
-static inline
-int ext4_setup_fname_crypto(struct inode *inode)
-{
-	return 0;
-}
-static inline void ext4_fname_crypto_free_buffer(struct ext4_str *p) { }
 static inline int ext4_fname_setup_filename(struct inode *dir,
-				     const struct qstr *iname,
-				     int lookup, struct ext4_filename *fname)
+			const struct qstr *iname,
+			int lookup, struct ext4_filename *fname)
 {
-	fname->usr_fname = iname;
-	fname->disk_name.name = (unsigned char *) iname->name;
-	fname->disk_name.len = iname->len;
-	return 0;
-}
-static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
-#endif
-
+	struct fscrypt_name name;
+	int err;
 
-/* crypto_key.c */
-void ext4_free_crypt_info(struct ext4_crypt_info *ci);
-void ext4_free_encryption_info(struct inode *inode, struct ext4_crypt_info *ci);
-int _ext4_get_encryption_info(struct inode *inode);
+	memset(fname, 0, sizeof(struct ext4_filename));
 
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-int ext4_has_encryption_key(struct inode *inode);
+	err = fscrypt_setup_filename(dir, iname, lookup, &name);
 
-static inline int ext4_get_encryption_info(struct inode *inode)
-{
-	struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
-
-	if (!ci ||
-	    (ci->ci_keyring_key &&
-	     (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
-					   (1 << KEY_FLAG_REVOKED) |
-					   (1 << KEY_FLAG_DEAD)))))
-		return _ext4_get_encryption_info(inode);
-	return 0;
+	fname->usr_fname = name.usr_fname;
+	fname->disk_name = name.disk_name;
+	fname->hinfo.hash = name.hash;
+	fname->hinfo.minor_hash = name.minor_hash;
+	fname->crypto_buf = name.crypto_buf;
+	return err;
 }
 
-static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
+static inline void ext4_fname_free_filename(struct ext4_filename *fname)
 {
-	return EXT4_I(inode)->i_crypt_info;
-}
+	struct fscrypt_name name;
 
-#else
-static inline int ext4_has_encryption_key(struct inode *inode)
-{
-	return 0;
+	name.crypto_buf = fname->crypto_buf;
+	fscrypt_free_filename(&name);
+
+	fname->crypto_buf.name = NULL;
+	fname->usr_fname = NULL;
+	fname->disk_name.name = NULL;
 }
-static inline int ext4_get_encryption_info(struct inode *inode)
+#else
+static inline int ext4_fname_setup_filename(struct inode *dir,
+		const struct qstr *iname,
+		int lookup, struct ext4_filename *fname)
 {
+	fname->usr_fname = iname;
+	fname->disk_name.name = (unsigned char *) iname->name;
+	fname->disk_name.len = iname->len;
 	return 0;
 }
-static inline struct ext4_crypt_info *ext4_encryption_info(struct inode *inode)
-{
-	return NULL;
-}
-#endif
+static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
 
+#define fscrypt_set_d_op(i)
+#define fscrypt_get_ctx			fscrypt_notsupp_get_ctx
+#define fscrypt_release_ctx		fscrypt_notsupp_release_ctx
+#define fscrypt_encrypt_page		fscrypt_notsupp_encrypt_page
+#define fscrypt_decrypt_page		fscrypt_notsupp_decrypt_page
+#define fscrypt_decrypt_bio_pages	fscrypt_notsupp_decrypt_bio_pages
+#define fscrypt_pullback_bio_page	fscrypt_notsupp_pullback_bio_page
+#define fscrypt_restore_control_page	fscrypt_notsupp_restore_control_page
+#define fscrypt_zeroout_range		fscrypt_notsupp_zeroout_range
+#define fscrypt_process_policy		fscrypt_notsupp_process_policy
+#define fscrypt_get_policy		fscrypt_notsupp_get_policy
+#define fscrypt_has_permitted_context	fscrypt_notsupp_has_permitted_context
+#define fscrypt_inherit_context		fscrypt_notsupp_inherit_context
+#define fscrypt_get_encryption_info	fscrypt_notsupp_get_encryption_info
+#define fscrypt_put_encryption_info	fscrypt_notsupp_put_encryption_info
+#define fscrypt_setup_filename		fscrypt_notsupp_setup_filename
+#define fscrypt_free_filename		fscrypt_notsupp_free_filename
+#define fscrypt_fname_encrypted_size	fscrypt_notsupp_fname_encrypted_size
+#define fscrypt_fname_alloc_buffer	fscrypt_notsupp_fname_alloc_buffer
+#define fscrypt_fname_free_buffer	fscrypt_notsupp_fname_free_buffer
+#define fscrypt_fname_disk_to_usr	fscrypt_notsupp_fname_disk_to_usr
+#define fscrypt_fname_usr_to_disk	fscrypt_notsupp_fname_usr_to_disk
+#endif
 
 /* dir.c */
 extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
@@ -2429,7 +2358,7 @@  extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *,
 extern int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
 				__u32 minor_hash,
 				struct ext4_dir_entry_2 *dirent,
-				struct ext4_str *ent_name);
+				struct fscrypt_str *ent_name);
 extern void ext4_htree_free_dir_info(struct dir_private_info *p);
 extern int ext4_find_dest_de(struct inode *dir, struct inode *inode,
 			     struct buffer_head *bh,
@@ -2619,7 +2548,7 @@  extern int ext4_generic_delete_entry(handle_t *handle,
 				     void *entry_buf,
 				     int buf_size,
 				     int csum_size);
-extern int ext4_empty_dir(struct inode *inode);
+extern bool ext4_empty_dir(struct inode *inode);
 
 /* resize.c */
 extern int ext4_group_add(struct super_block *sb,
@@ -3101,7 +3030,7 @@  extern int ext4_delete_inline_entry(handle_t *handle,
 				    struct ext4_dir_entry_2 *de_del,
 				    struct buffer_head *bh,
 				    int *has_inline_data);
-extern int empty_inline_dir(struct inode *dir, int *has_inline_data);
+extern bool empty_inline_dir(struct inode *dir, int *has_inline_data);
 extern struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
 					struct ext4_dir_entry_2 **parent_de,
 					int *retval);
diff --git a/fs/ext4/ext4_crypto.h b/fs/ext4/ext4_crypto.h
deleted file mode 100644
index 1f73c29..0000000
--- a/fs/ext4/ext4_crypto.h
+++ /dev/null
@@ -1,159 +0,0 @@ 
-/*
- * linux/fs/ext4/ext4_crypto.h
- *
- * Copyright (C) 2015, Google, Inc.
- *
- * This contains encryption header content for ext4
- *
- * Written by Michael Halcrow, 2015.
- */
-
-#ifndef _EXT4_CRYPTO_H
-#define _EXT4_CRYPTO_H
-
-#include <linux/fs.h>
-
-#define EXT4_KEY_DESCRIPTOR_SIZE 8
-
-/* Policy provided via an ioctl on the topmost directory */
-struct ext4_encryption_policy {
-	char version;
-	char contents_encryption_mode;
-	char filenames_encryption_mode;
-	char flags;
-	char master_key_descriptor[EXT4_KEY_DESCRIPTOR_SIZE];
-} __attribute__((__packed__));
-
-#define EXT4_ENCRYPTION_CONTEXT_FORMAT_V1 1
-#define EXT4_KEY_DERIVATION_NONCE_SIZE 16
-
-#define EXT4_POLICY_FLAGS_PAD_4		0x00
-#define EXT4_POLICY_FLAGS_PAD_8		0x01
-#define EXT4_POLICY_FLAGS_PAD_16	0x02
-#define EXT4_POLICY_FLAGS_PAD_32	0x03
-#define EXT4_POLICY_FLAGS_PAD_MASK	0x03
-#define EXT4_POLICY_FLAGS_VALID		0x03
-
-/**
- * Encryption context for inode
- *
- * Protector format:
- *  1 byte: Protector format (1 = this version)
- *  1 byte: File contents encryption mode
- *  1 byte: File names encryption mode
- *  1 byte: Reserved
- *  8 bytes: Master Key descriptor
- *  16 bytes: Encryption Key derivation nonce
- */
-struct ext4_encryption_context {
-	char format;
-	char contents_encryption_mode;
-	char filenames_encryption_mode;
-	char flags;
-	char master_key_descriptor[EXT4_KEY_DESCRIPTOR_SIZE];
-	char nonce[EXT4_KEY_DERIVATION_NONCE_SIZE];
-} __attribute__((__packed__));
-
-/* Encryption parameters */
-#define EXT4_XTS_TWEAK_SIZE 16
-#define EXT4_AES_128_ECB_KEY_SIZE 16
-#define EXT4_AES_256_GCM_KEY_SIZE 32
-#define EXT4_AES_256_CBC_KEY_SIZE 32
-#define EXT4_AES_256_CTS_KEY_SIZE 32
-#define EXT4_AES_256_XTS_KEY_SIZE 64
-#define EXT4_MAX_KEY_SIZE 64
-
-#define EXT4_KEY_DESC_PREFIX "ext4:"
-#define EXT4_KEY_DESC_PREFIX_SIZE 5
-
-/* This is passed in from userspace into the kernel keyring */
-struct ext4_encryption_key {
-        __u32 mode;
-        char raw[EXT4_MAX_KEY_SIZE];
-        __u32 size;
-} __attribute__((__packed__));
-
-struct ext4_crypt_info {
-	char		ci_data_mode;
-	char		ci_filename_mode;
-	char		ci_flags;
-	struct crypto_skcipher *ci_ctfm;
-	struct key	*ci_keyring_key;
-	char		ci_master_key[EXT4_KEY_DESCRIPTOR_SIZE];
-};
-
-#define EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL             0x00000001
-#define EXT4_WRITE_PATH_FL			      0x00000002
-
-struct ext4_crypto_ctx {
-	union {
-		struct {
-			struct page *bounce_page;       /* Ciphertext page */
-			struct page *control_page;      /* Original page  */
-		} w;
-		struct {
-			struct bio *bio;
-			struct work_struct work;
-		} r;
-		struct list_head free_list;     /* Free list */
-	};
-	char flags;                      /* Flags */
-	char mode;                       /* Encryption mode for tfm */
-};
-
-struct ext4_completion_result {
-	struct completion completion;
-	int res;
-};
-
-#define DECLARE_EXT4_COMPLETION_RESULT(ecr) \
-	struct ext4_completion_result ecr = { \
-		COMPLETION_INITIALIZER((ecr).completion), 0 }
-
-static inline int ext4_encryption_key_size(int mode)
-{
-	switch (mode) {
-	case EXT4_ENCRYPTION_MODE_AES_256_XTS:
-		return EXT4_AES_256_XTS_KEY_SIZE;
-	case EXT4_ENCRYPTION_MODE_AES_256_GCM:
-		return EXT4_AES_256_GCM_KEY_SIZE;
-	case EXT4_ENCRYPTION_MODE_AES_256_CBC:
-		return EXT4_AES_256_CBC_KEY_SIZE;
-	case EXT4_ENCRYPTION_MODE_AES_256_CTS:
-		return EXT4_AES_256_CTS_KEY_SIZE;
-	default:
-		BUG();
-	}
-	return 0;
-}
-
-#define EXT4_FNAME_NUM_SCATTER_ENTRIES	4
-#define EXT4_CRYPTO_BLOCK_SIZE		16
-#define EXT4_FNAME_CRYPTO_DIGEST_SIZE	32
-
-struct ext4_str {
-	unsigned char *name;
-	u32 len;
-};
-
-/**
- * For encrypted symlinks, the ciphertext length is stored at the beginning
- * of the string in little-endian format.
- */
-struct ext4_encrypted_symlink_data {
-	__le16 len;
-	char encrypted_path[1];
-} __attribute__((__packed__));
-
-/**
- * This function is used to calculate the disk space required to
- * store a filename of length l in encrypted symlink format.
- */
-static inline u32 encrypted_symlink_data_len(u32 l)
-{
-	if (l < EXT4_CRYPTO_BLOCK_SIZE)
-		l = EXT4_CRYPTO_BLOCK_SIZE;
-	return (l + sizeof(struct ext4_encrypted_symlink_data) - 1);
-}
-
-#endif	/* _EXT4_CRYPTO_H */
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index fa2208b..9d262b4 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -308,10 +308,10 @@  static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
 	struct inode *inode = file->f_mapping->host;
 
 	if (ext4_encrypted_inode(inode)) {
-		int err = ext4_get_encryption_info(inode);
+		int err = fscrypt_get_encryption_info(inode);
 		if (err)
 			return 0;
-		if (ext4_encryption_info(inode) == NULL)
+		if (!fscrypt_has_encryption_key(inode))
 			return -ENOKEY;
 	}
 	file_accessed(file);
@@ -367,16 +367,16 @@  static int ext4_file_open(struct inode * inode, struct file * filp)
 		}
 	}
 	if (ext4_encrypted_inode(inode)) {
-		ret = ext4_get_encryption_info(inode);
+		ret = fscrypt_get_encryption_info(inode);
 		if (ret)
 			return -EACCES;
-		if (ext4_encryption_info(inode) == NULL)
+		if (!fscrypt_has_encryption_key(inode))
 			return -ENOKEY;
 	}
 
 	dir = dget_parent(file_dentry(filp));
 	if (ext4_encrypted_inode(d_inode(dir)) &&
-	    !ext4_is_child_context_consistent_with_parent(d_inode(dir), inode)) {
+			!fscrypt_has_permitted_context(d_inode(dir), inode)) {
 		ext4_warning(inode->i_sb,
 			     "Inconsistent encryption contexts: %lu/%lu\n",
 			     (unsigned long) d_inode(dir)->i_ino,
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 237b877..69bb343 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -767,10 +767,10 @@  struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
 	if ((ext4_encrypted_inode(dir) ||
 	     DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb))) &&
 	    (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
-		err = ext4_get_encryption_info(dir);
+		err = fscrypt_get_encryption_info(dir);
 		if (err)
 			return ERR_PTR(err);
-		if (ext4_encryption_info(dir) == NULL)
+		if (!fscrypt_has_encryption_key(dir))
 			return ERR_PTR(-EPERM);
 		if (!handle)
 			nblocks += EXT4_DATA_TRANS_BLOCKS(dir->i_sb);
@@ -1115,7 +1115,8 @@  got:
 	}
 
 	if (encrypt) {
-		err = ext4_inherit_context(dir, inode);
+		/* give pointer to avoid set_context with journal ops. */
+		err = fscrypt_inherit_context(dir, inode, &encrypt, true);
 		if (err)
 			goto fail_free_drop;
 	}
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index 7bc6c85..5ea6337 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -1326,7 +1326,7 @@  int htree_inlinedir_to_tree(struct file *dir_file,
 	struct ext4_iloc iloc;
 	void *dir_buf = NULL;
 	struct ext4_dir_entry_2 fake;
-	struct ext4_str tmp_str;
+	struct fscrypt_str tmp_str;
 
 	ret = ext4_get_inode_loc(inode, &iloc);
 	if (ret)
@@ -1739,20 +1739,20 @@  ext4_get_inline_entry(struct inode *inode,
 	return (struct ext4_dir_entry_2 *)(inline_pos + offset);
 }
 
-int empty_inline_dir(struct inode *dir, int *has_inline_data)
+bool empty_inline_dir(struct inode *dir, int *has_inline_data)
 {
 	int err, inline_size;
 	struct ext4_iloc iloc;
 	void *inline_pos;
 	unsigned int offset;
 	struct ext4_dir_entry_2 *de;
-	int ret = 1;
+	bool ret = true;
 
 	err = ext4_get_inode_loc(dir, &iloc);
 	if (err) {
 		EXT4_ERROR_INODE(dir, "error %d getting inode %lu block",
 				 err, dir->i_ino);
-		return 1;
+		return true;
 	}
 
 	down_read(&EXT4_I(dir)->xattr_sem);
@@ -1766,7 +1766,7 @@  int empty_inline_dir(struct inode *dir, int *has_inline_data)
 		ext4_warning(dir->i_sb,
 			     "bad inline directory (dir #%lu) - no `..'",
 			     dir->i_ino);
-		ret = 1;
+		ret = true;
 		goto out;
 	}
 
@@ -1784,11 +1784,11 @@  int empty_inline_dir(struct inode *dir, int *has_inline_data)
 				     dir->i_ino, le32_to_cpu(de->inode),
 				     le16_to_cpu(de->rec_len), de->name_len,
 				     inline_size);
-			ret = 1;
+			ret = true;
 			goto out;
 		}
 		if (le32_to_cpu(de->inode)) {
-			ret = 0;
+			ret = false;
 			goto out;
 		}
 		offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 981a1fc..8f44605 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -386,7 +386,7 @@  int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
 	int ret;
 
 	if (ext4_encrypted_inode(inode))
-		return ext4_encrypted_zeroout(inode, lblk, pblk, len);
+		return fscrypt_zeroout_range(inode, lblk, pblk, len);
 
 	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
 	if (ret > 0)
@@ -1134,7 +1134,7 @@  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 (decrypt)
-		err = ext4_decrypt(page);
+		err = fscrypt_decrypt_page(page);
 	return err;
 }
 #endif
@@ -3611,9 +3611,9 @@  static int __ext4_block_zero_page_range(handle_t *handle,
 		if (S_ISREG(inode->i_mode) &&
 		    ext4_encrypted_inode(inode)) {
 			/* We expect the key to be set. */
-			BUG_ON(!ext4_has_encryption_key(inode));
+			BUG_ON(!fscrypt_has_encryption_key(inode));
 			BUG_ON(blocksize != PAGE_SIZE);
-			WARN_ON_ONCE(ext4_decrypt(page));
+			WARN_ON_ONCE(fscrypt_decrypt_page(page));
 		}
 	}
 	if (ext4_should_journal_data(inode)) {
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index eae5917..1c4f52f 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -772,19 +772,13 @@  resizefs_out:
 		return ext4_ext_precache(inode);
 	case EXT4_IOC_SET_ENCRYPTION_POLICY: {
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-		struct ext4_encryption_policy policy;
-		int err = 0;
+		struct fscrypt_policy policy;
 
 		if (copy_from_user(&policy,
-				   (struct ext4_encryption_policy __user *)arg,
-				   sizeof(policy))) {
-			err = -EFAULT;
-			goto encryption_policy_out;
-		}
-
-		err = ext4_process_policy(&policy, inode);
-encryption_policy_out:
-		return err;
+				   (struct fscrypt_policy __user *)arg,
+				   sizeof(policy)))
+			return -EFAULT;
+		return fscrypt_process_policy(inode, &policy);
 #else
 		return -EOPNOTSUPP;
 #endif
@@ -827,12 +821,12 @@  encryption_policy_out:
 	}
 	case EXT4_IOC_GET_ENCRYPTION_POLICY: {
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-		struct ext4_encryption_policy policy;
+		struct fscrypt_policy policy;
 		int err = 0;
 
 		if (!ext4_encrypted_inode(inode))
 			return -ENOENT;
-		err = ext4_get_policy(inode, &policy);
+		err = fscrypt_get_policy(inode, &policy);
 		if (err)
 			return err;
 		if (copy_to_user((void __user *)arg, &policy, sizeof(policy)))
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 48e4b89..9cab638 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -612,19 +612,21 @@  static struct stats dx_show_leaf(struct inode *dir,
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 				int len;
 				char *name;
-				struct ext4_str fname_crypto_str
-					= {.name = NULL, .len = 0};
+				struct fscrypt_str fname_crypto_str =
+					FSTR_INIT(NULL, 0);
+				struct qstr istr =
+					QSTR_INIT(de->name, de->name_len);
 				int res = 0;
 
 				name  = de->name;
 				len = de->name_len;
 				if (ext4_encrypted_inode(inode))
-					res = ext4_get_encryption_info(dir);
+					res = fscrypt_get_encryption_info(dir);
 				if (res) {
 					printk(KERN_WARNING "Error setting up"
 					       " fname crypto: %d\n", res);
 				}
-				if (ctx == NULL) {
+				if (!fscrypt_has_encryption_key(inode)) {
 					/* Directory is not encrypted */
 					ext4fs_dirhash(de->name,
 						de->name_len, &h);
@@ -633,9 +635,12 @@  static struct stats dx_show_leaf(struct inode *dir,
 					       (unsigned) ((char *) de
 							   - base));
 				} else {
+					struct fscrypt_str de_name =
+						FSTR_INIT(name, len);
+
 					/* Directory is encrypted */
-					res = ext4_fname_crypto_alloc_buffer(
-						ctx, de->name_len,
+					res = fscrypt_fname_alloc_buffer(
+						inode, len,
 						&fname_crypto_str);
 					if (res < 0) {
 						printk(KERN_WARNING "Error "
@@ -644,8 +649,9 @@  static struct stats dx_show_leaf(struct inode *dir,
 							"crypto\n");
 						ctx = NULL;
 					}
-					res = ext4_fname_disk_to_usr(ctx, NULL, de,
-							&fname_crypto_str);
+					res = fscrypt_fname_disk_to_usr(inode,
+						0, 0, &de_name,
+						&fname_crypto_str);
 					if (res < 0) {
 						printk(KERN_WARNING "Error "
 							"converting filename "
@@ -662,8 +668,8 @@  static struct stats dx_show_leaf(struct inode *dir,
 					printk("%*.s:(E)%x.%u ", len, name,
 					       h.hash, (unsigned) ((char *) de
 								   - base));
-					ext4_fname_crypto_free_buffer(
-						&fname_crypto_str);
+					fscrypt_fname_free_buffer(
+							&fname_crypto_str);
 				}
 #else
 				int len = de->name_len;
@@ -952,7 +958,7 @@  static int htree_dirblock_to_tree(struct file *dir_file,
 	struct buffer_head *bh;
 	struct ext4_dir_entry_2 *de, *top;
 	int err = 0, count = 0;
-	struct ext4_str fname_crypto_str = {.name = NULL, .len = 0}, tmp_str;
+	struct fscrypt_str fname_crypto_str = FSTR_INIT(NULL, 0), tmp_str;
 
 	dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n",
 							(unsigned long)block));
@@ -967,12 +973,12 @@  static int htree_dirblock_to_tree(struct file *dir_file,
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 	/* Check if the directory is encrypted */
 	if (ext4_encrypted_inode(dir)) {
-		err = ext4_get_encryption_info(dir);
+		err = fscrypt_get_encryption_info(dir);
 		if (err < 0) {
 			brelse(bh);
 			return err;
 		}
-		err = ext4_fname_crypto_alloc_buffer(dir, EXT4_NAME_LEN,
+		err = fscrypt_fname_alloc_buffer(dir, EXT4_NAME_LEN,
 						     &fname_crypto_str);
 		if (err < 0) {
 			brelse(bh);
@@ -1003,10 +1009,13 @@  static int htree_dirblock_to_tree(struct file *dir_file,
 				   &tmp_str);
 		} else {
 			int save_len = fname_crypto_str.len;
+			struct fscrypt_str de_name = FSTR_INIT(de->name,
+								de->name_len);
 
 			/* Directory is encrypted */
-			err = ext4_fname_disk_to_usr(dir, hinfo, de,
-						     &fname_crypto_str);
+			err = fscrypt_fname_disk_to_usr(dir, hinfo->hash,
+					hinfo->minor_hash, &de_name,
+					&fname_crypto_str);
 			if (err < 0) {
 				count = err;
 				goto errout;
@@ -1025,7 +1034,7 @@  static int htree_dirblock_to_tree(struct file *dir_file,
 errout:
 	brelse(bh);
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-	ext4_fname_crypto_free_buffer(&fname_crypto_str);
+	fscrypt_fname_free_buffer(&fname_crypto_str);
 #endif
 	return count;
 }
@@ -1050,7 +1059,7 @@  int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 	int count = 0;
 	int ret, err;
 	__u32 hashval;
-	struct ext4_str tmp_str;
+	struct fscrypt_str tmp_str;
 
 	dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n",
 		       start_hash, start_minor_hash));
@@ -1558,26 +1567,23 @@  static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi
 	struct ext4_dir_entry_2 *de;
 	struct buffer_head *bh;
 
-       if (ext4_encrypted_inode(dir)) {
-               int res = ext4_get_encryption_info(dir);
+	if (ext4_encrypted_inode(dir)) {
+		int res = fscrypt_get_encryption_info(dir);
 
 		/*
-		 * This should be a properly defined flag for
-		 * dentry->d_flags when we uplift this to the VFS.
-		 * d_fsdata is set to (void *) 1 if if the dentry is
+		 * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is
 		 * created while the directory was encrypted and we
 		 * don't have access to the key.
 		 */
-	       dentry->d_fsdata = NULL;
-	       if (ext4_encryption_info(dir))
-		       dentry->d_fsdata = (void *) 1;
-	       d_set_d_op(dentry, &ext4_encrypted_d_ops);
-	       if (res && res != -ENOKEY)
-		       return ERR_PTR(res);
-       }
+		if (fscrypt_has_encryption_key(dir))
+			fscrypt_set_encrypted_dentry(dentry);
+		fscrypt_set_d_op(dentry);
+		if (res && res != -ENOKEY)
+			return ERR_PTR(res);
+	}
 
-	if (dentry->d_name.len > EXT4_NAME_LEN)
-		return ERR_PTR(-ENAMETOOLONG);
+       if (dentry->d_name.len > EXT4_NAME_LEN)
+	       return ERR_PTR(-ENAMETOOLONG);
 
 	bh = ext4_find_entry(dir, &dentry->d_name, &de, NULL);
 	if (IS_ERR(bh))
@@ -1604,11 +1610,9 @@  static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi
 		}
 		if (!IS_ERR(inode) && ext4_encrypted_inode(dir) &&
 		    (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
-		    !ext4_is_child_context_consistent_with_parent(dir,
-								  inode)) {
+		    !fscrypt_has_permitted_context(dir, inode)) {
 			int nokey = ext4_encrypted_inode(inode) &&
-				!ext4_encryption_info(inode);
-
+				!fscrypt_has_encryption_key(inode);
 			iput(inode);
 			if (nokey)
 				return ERR_PTR(-ENOKEY);
@@ -2685,13 +2689,13 @@  out_stop:
 /*
  * routine to check that the specified directory is empty (for rmdir)
  */
-int ext4_empty_dir(struct inode *inode)
+bool ext4_empty_dir(struct inode *inode)
 {
 	unsigned int offset;
 	struct buffer_head *bh;
 	struct ext4_dir_entry_2 *de, *de1;
 	struct super_block *sb;
-	int err = 0;
+	bool err = false;
 
 	if (ext4_has_inline_data(inode)) {
 		int has_inline_data = 1;
@@ -2704,11 +2708,11 @@  int ext4_empty_dir(struct inode *inode)
 	sb = inode->i_sb;
 	if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)) {
 		EXT4_ERROR_INODE(inode, "invalid size");
-		return 1;
+		return true;
 	}
 	bh = ext4_read_dirblock(inode, 0, EITHER);
 	if (IS_ERR(bh))
-		return 1;
+		return true;
 
 	de = (struct ext4_dir_entry_2 *) bh->b_data;
 	de1 = ext4_next_entry(de, sb->s_blocksize);
@@ -2717,7 +2721,7 @@  int ext4_empty_dir(struct inode *inode)
 			strcmp(".", de->name) || strcmp("..", de1->name)) {
 		ext4_warning_inode(inode, "directory missing '.' and/or '..'");
 		brelse(bh);
-		return 1;
+		return true;
 	}
 	offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
 		 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
@@ -2730,7 +2734,7 @@  int ext4_empty_dir(struct inode *inode)
 			lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb);
 			bh = ext4_read_dirblock(inode, lblock, EITHER);
 			if (IS_ERR(bh))
-				return 1;
+				return true;
 			de = (struct ext4_dir_entry_2 *) bh->b_data;
 		}
 		if (ext4_check_dir_entry(inode, NULL, de, bh,
@@ -2742,13 +2746,13 @@  int ext4_empty_dir(struct inode *inode)
 		}
 		if (le32_to_cpu(de->inode)) {
 			brelse(bh);
-			return 0;
+			return false;
 		}
 		offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
 		de = ext4_next_entry(de, sb->s_blocksize);
 	}
 	brelse(bh);
-	return 1;
+	return true;
 }
 
 /*
@@ -3071,8 +3075,8 @@  static int ext4_symlink(struct inode *dir,
 	int err, len = strlen(symname);
 	int credits;
 	bool encryption_required;
-	struct ext4_str disk_link;
-	struct ext4_encrypted_symlink_data *sd = NULL;
+	struct fscrypt_str disk_link;
+	struct fscrypt_symlink_data *sd = NULL;
 
 	disk_link.len = len + 1;
 	disk_link.name = (char *) symname;
@@ -3080,13 +3084,13 @@  static int ext4_symlink(struct inode *dir,
 	encryption_required = (ext4_encrypted_inode(dir) ||
 			       DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir->i_sb)));
 	if (encryption_required) {
-		err = ext4_get_encryption_info(dir);
+		err = fscrypt_get_encryption_info(dir);
 		if (err)
 			return err;
-		if (ext4_encryption_info(dir) == NULL)
+		if (!fscrypt_has_encryption_key(dir))
 			return -EPERM;
-		disk_link.len = (ext4_fname_encrypted_size(dir, len) +
-				 sizeof(struct ext4_encrypted_symlink_data));
+		disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
+				 sizeof(struct fscrypt_symlink_data));
 		sd = kzalloc(disk_link.len, GFP_KERNEL);
 		if (!sd)
 			return -ENOMEM;
@@ -3134,13 +3138,12 @@  static int ext4_symlink(struct inode *dir,
 
 	if (encryption_required) {
 		struct qstr istr;
-		struct ext4_str ostr;
+		struct fscrypt_str ostr =
+			FSTR_INIT(sd->encrypted_path, disk_link.len);
 
 		istr.name = (const unsigned char *) symname;
 		istr.len = len;
-		ostr.name = sd->encrypted_path;
-		ostr.len = disk_link.len;
-		err = ext4_fname_usr_to_disk(inode, &istr, &ostr);
+		err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
 		if (err < 0)
 			goto err_drop_inode;
 		sd->len = cpu_to_le16(ostr.len);
@@ -3229,7 +3232,7 @@  static int ext4_link(struct dentry *old_dentry,
 	if (inode->i_nlink >= EXT4_LINK_MAX)
 		return -EMLINK;
 	if (ext4_encrypted_inode(dir) &&
-	    !ext4_is_child_context_consistent_with_parent(dir, inode))
+			!fscrypt_has_permitted_context(dir, inode))
 		return -EPERM;
 
        if ((ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) &&
@@ -3552,8 +3555,7 @@  static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 	if ((old.dir != new.dir) &&
 	    ext4_encrypted_inode(new.dir) &&
-	    !ext4_is_child_context_consistent_with_parent(new.dir,
-							  old.inode)) {
+	    !fscrypt_has_permitted_context(new.dir, old.inode)) {
 		retval = -EPERM;
 		goto end_rename;
 	}
@@ -3725,10 +3727,8 @@  static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if ((ext4_encrypted_inode(old_dir) ||
 	     ext4_encrypted_inode(new_dir)) &&
 	    (old_dir != new_dir) &&
-	    (!ext4_is_child_context_consistent_with_parent(new_dir,
-							   old.inode) ||
-	     !ext4_is_child_context_consistent_with_parent(old_dir,
-							   new.inode)))
+	    (!fscrypt_has_permitted_context(new_dir, old.inode) ||
+	     !fscrypt_has_permitted_context(old_dir, new.inode)))
 		return -EPERM;
 
 	if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index e4fc8ea..f124b24 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -24,6 +24,7 @@ 
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/backing-dev.h>
+#include <linux/fscrypto.h>
 
 #include "ext4_jbd2.h"
 #include "xattr.h"
@@ -67,7 +68,6 @@  static void ext4_finish_bio(struct bio *bio)
 		struct page *page = bvec->bv_page;
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
 		struct page *data_page = NULL;
-		struct ext4_crypto_ctx *ctx = NULL;
 #endif
 		struct buffer_head *bh, *head;
 		unsigned bio_start = bvec->bv_offset;
@@ -82,8 +82,7 @@  static void ext4_finish_bio(struct bio *bio)
 		if (!page->mapping) {
 			/* The bounce data pages are unmapped. */
 			data_page = page;
-			ctx = (struct ext4_crypto_ctx *)page_private(data_page);
-			page = ctx->w.control_page;
+			fscrypt_pullback_bio_page(&page, false);
 		}
 #endif
 
@@ -113,8 +112,8 @@  static void ext4_finish_bio(struct bio *bio)
 		local_irq_restore(flags);
 		if (!under_io) {
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-			if (ctx)
-				ext4_restore_control_page(data_page);
+			if (data_page)
+				fscrypt_restore_control_page(data_page);
 #endif
 			end_page_writeback(page);
 		}
@@ -474,7 +473,7 @@  int ext4_bio_write_page(struct ext4_io_submit *io,
 		gfp_t gfp_flags = GFP_NOFS;
 
 	retry_encrypt:
-		data_page = ext4_encrypt(inode, page, gfp_flags);
+		data_page = fscrypt_encrypt_page(inode, page, gfp_flags);
 		if (IS_ERR(data_page)) {
 			ret = PTR_ERR(data_page);
 			if (ret == -ENOMEM && wbc->sync_mode == WB_SYNC_ALL) {
@@ -512,7 +511,7 @@  int ext4_bio_write_page(struct ext4_io_submit *io,
 	if (ret) {
 	out:
 		if (data_page)
-			ext4_restore_control_page(data_page);
+			fscrypt_restore_control_page(data_page);
 		printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret);
 		redirty_page_for_writepage(wbc, page);
 		do {
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index dc54a4b..13f3476 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -46,37 +46,6 @@ 
 
 #include "ext4.h"
 
-/*
- * Call ext4_decrypt on every single page, reusing the encryption
- * context.
- */
-static void completion_pages(struct work_struct *work)
-{
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	struct ext4_crypto_ctx *ctx =
-		container_of(work, struct ext4_crypto_ctx, r.work);
-	struct bio	*bio	= ctx->r.bio;
-	struct bio_vec	*bv;
-	int		i;
-
-	bio_for_each_segment_all(bv, bio, i) {
-		struct page *page = bv->bv_page;
-
-		int ret = ext4_decrypt(page);
-		if (ret) {
-			WARN_ON_ONCE(1);
-			SetPageError(page);
-		} else
-			SetPageUptodate(page);
-		unlock_page(page);
-	}
-	ext4_release_crypto_ctx(ctx);
-	bio_put(bio);
-#else
-	BUG();
-#endif
-}
-
 static inline bool ext4_bio_encrypted(struct bio *bio)
 {
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
@@ -104,14 +73,10 @@  static void mpage_end_io(struct bio *bio)
 	int i;
 
 	if (ext4_bio_encrypted(bio)) {
-		struct ext4_crypto_ctx *ctx = bio->bi_private;
-
 		if (bio->bi_error) {
-			ext4_release_crypto_ctx(ctx);
+			fscrypt_release_ctx(bio->bi_private);
 		} else {
-			INIT_WORK(&ctx->r.work, completion_pages);
-			ctx->r.bio = bio;
-			queue_work(ext4_read_workqueue, &ctx->r.work);
+			fscrypt_decrypt_bio_pages(bio->bi_private, bio);
 			return;
 		}
 	}
@@ -275,11 +240,11 @@  int ext4_mpage_readpages(struct address_space *mapping,
 			bio = NULL;
 		}
 		if (bio == NULL) {
-			struct ext4_crypto_ctx *ctx = NULL;
+			struct fscrypt_ctx *ctx = NULL;
 
 			if (ext4_encrypted_inode(inode) &&
 			    S_ISREG(inode->i_mode)) {
-				ctx = ext4_get_crypto_ctx(inode, GFP_NOFS);
+				ctx = fscrypt_get_ctx(inode, GFP_NOFS);
 				if (IS_ERR(ctx))
 					goto set_error_page;
 			}
@@ -287,7 +252,7 @@  int ext4_mpage_readpages(struct address_space *mapping,
 				min_t(int, nr_pages, BIO_MAX_PAGES));
 			if (!bio) {
 				if (ctx)
-					ext4_release_crypto_ctx(ctx);
+					fscrypt_release_ctx(ctx);
 				goto set_error_page;
 			}
 			bio->bi_bdev = bdev;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 304c712..80ee248 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -944,9 +944,6 @@  static struct inode *ext4_alloc_inode(struct super_block *sb)
 	ei->i_datasync_tid = 0;
 	atomic_set(&ei->i_unwritten, 0);
 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	ei->i_crypt_info = NULL;
-#endif
 	return &ei->vfs_inode;
 }
 
@@ -1025,8 +1022,7 @@  void ext4_clear_inode(struct inode *inode)
 		EXT4_I(inode)->jinode = NULL;
 	}
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
-	if (EXT4_I(inode)->i_crypt_info)
-		ext4_free_encryption_info(inode, EXT4_I(inode)->i_crypt_info);
+	fscrypt_put_encryption_info(inode, NULL);
 #endif
 }
 
@@ -1093,6 +1089,83 @@  static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
 	return try_to_free_buffers(page);
 }
 
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
+{
+	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
+}
+
+static int ext4_prepare_context(struct inode *inode)
+{
+	return ext4_convert_inline_data(inode);
+}
+
+static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
+							void *fs_data)
+{
+	handle_t *handle;
+	int res, res2;
+
+	/* fs_data is null when internally used. */
+	if (fs_data) {
+		res  = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+				EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
+				len, 0);
+		if (!res) {
+			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
+			ext4_clear_inode_state(inode,
+					EXT4_STATE_MAY_INLINE_DATA);
+		}
+		return res;
+	}
+
+	handle = ext4_journal_start(inode, EXT4_HT_MISC,
+			ext4_jbd2_credits_xattr(inode));
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+
+	res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
+			EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
+			len, 0);
+	if (!res) {
+		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
+		res = ext4_mark_inode_dirty(handle, inode);
+		if (res)
+			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
+	}
+	res2 = ext4_journal_stop(handle);
+	if (!res)
+		res = res2;
+	return res;
+}
+
+static int ext4_dummy_context(struct inode *inode)
+{
+	return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
+}
+
+static unsigned ext4_max_namelen(struct inode *inode)
+{
+	return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
+		EXT4_NAME_LEN;
+}
+
+static struct fscrypt_operations ext4_cryptops = {
+	.get_context		= ext4_get_context,
+	.prepare_context	= ext4_prepare_context,
+	.set_context		= ext4_set_context,
+	.dummy_context		= ext4_dummy_context,
+	.is_encrypted		= ext4_encrypted_inode,
+	.empty_dir		= ext4_empty_dir,
+	.max_namelen		= ext4_max_namelen,
+};
+#else
+static struct fscrypt_operations ext4_cryptops = {
+	.is_encrypted		= ext4_encrypted_inode,
+};
+#endif
+
 #ifdef CONFIG_QUOTA
 static char *quotatypes[] = INITQFNAMES;
 #define QTYPE2NAME(t) (quotatypes[t])
@@ -3692,6 +3765,7 @@  static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_op = &ext4_sops;
 	sb->s_export_op = &ext4_export_ops;
 	sb->s_xattr = ext4_xattr_handlers;
+	sb->s_cop = &ext4_cryptops;
 #ifdef CONFIG_QUOTA
 	sb->dq_op = &ext4_quota_operations;
 	if (ext4_has_feature_quota(sb))
@@ -5425,7 +5499,6 @@  out5:
 
 static void __exit ext4_exit_fs(void)
 {
-	ext4_exit_crypto();
 	ext4_destroy_lazyinit_thread();
 	unregister_as_ext2();
 	unregister_as_ext3();
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
index 75ed5c2..1f4b19f 100644
--- a/fs/ext4/symlink.c
+++ b/fs/ext4/symlink.c
@@ -22,23 +22,22 @@ 
 #include "ext4.h"
 #include "xattr.h"
 
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
 static const char *ext4_encrypted_get_link(struct dentry *dentry,
 					   struct inode *inode,
 					   struct delayed_call *done)
 {
 	struct page *cpage = NULL;
 	char *caddr, *paddr = NULL;
-	struct ext4_str cstr, pstr;
-	struct ext4_encrypted_symlink_data *sd;
+	struct fscrypt_str cstr, pstr;
+	struct fscrypt_symlink_data *sd;
 	loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
 	int res;
-	u32 plen, max_size = inode->i_sb->s_blocksize;
+	u32 max_size = inode->i_sb->s_blocksize;
 
 	if (!dentry)
 		return ERR_PTR(-ECHILD);
 
-	res = ext4_get_encryption_info(inode);
+	res = fscrypt_get_encryption_info(inode);
 	if (res)
 		return ERR_PTR(res);
 
@@ -54,30 +53,29 @@  static const char *ext4_encrypted_get_link(struct dentry *dentry,
 	}
 
 	/* Symlink is encrypted */
-	sd = (struct ext4_encrypted_symlink_data *)caddr;
+	sd = (struct fscrypt_symlink_data *)caddr;
 	cstr.name = sd->encrypted_path;
 	cstr.len  = le16_to_cpu(sd->len);
 	if ((cstr.len +
-	     sizeof(struct ext4_encrypted_symlink_data) - 1) >
+	     sizeof(struct fscrypt_symlink_data) - 1) >
 	    max_size) {
 		/* Symlink data on the disk is corrupted */
 		res = -EFSCORRUPTED;
 		goto errout;
 	}
-	plen = (cstr.len < EXT4_FNAME_CRYPTO_DIGEST_SIZE*2) ?
-		EXT4_FNAME_CRYPTO_DIGEST_SIZE*2 : cstr.len;
-	paddr = kmalloc(plen + 1, GFP_NOFS);
-	if (!paddr) {
-		res = -ENOMEM;
+
+	res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
+	if (res)
 		goto errout;
-	}
-	pstr.name = paddr;
-	pstr.len = plen;
-	res = _ext4_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
+
+	res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
 	if (res < 0)
 		goto errout;
+
+	paddr = pstr.name;
+
 	/* Null-terminate the name */
-	if (res <= plen)
+	if (res <= pstr.len)
 		paddr[res] = '\0';
 	if (cpage)
 		put_page(cpage);
@@ -99,7 +97,6 @@  const struct inode_operations ext4_encrypted_symlink_inode_operations = {
 	.listxattr	= ext4_listxattr,
 	.removexattr	= generic_removexattr,
 };
-#endif
 
 const struct inode_operations ext4_symlink_inode_operations = {
 	.readlink	= generic_readlink,