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Commit 2d5cb296 authored by Theodore Ts'o's avatar Theodore Ts'o Committed by Mohamad Ayyash
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ext4 crypto: ext4_page_crypto() doesn't need a encryption context 



Since ext4_page_crypto() doesn't need an encryption context (at least
not any more), this allows us to simplify a number function signature
and also allows us to avoid needing to allocate a context in
ext4_block_write_begin().  It also means we no longer need a separate
ext4_decrypt_one() function.

Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
Signed-off-by: default avatarTheodore Ts'o <tytso@google.com>
Change-Id: Ibf9cad24bac3011cd59d66f1070859719c864dc0
parent dbcded04

fs/ext4/crypto.c

+5 −23
Original line number Diff line number Diff line
@@ -253,8 +253,7 @@ typedef enum { 
	EXT4_ENCRYPT,

} ext4_direction_t;



static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,

			    struct inode *inode,

static int ext4_page_crypto(struct inode *inode,

			    ext4_direction_t rw,

			    pgoff_t index,

			    struct page *src_page,
@@ -353,7 +352,7 @@ struct page *ext4_encrypt(struct inode *inode, 
	if (IS_ERR(ciphertext_page))

		goto errout;

	ctx->w.control_page = plaintext_page;

	err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, plaintext_page->index,

	err = ext4_page_crypto(inode, EXT4_ENCRYPT, plaintext_page->index,

			       plaintext_page, ciphertext_page);

	if (err) {

		ciphertext_page = ERR_PTR(err);
@@ -378,31 +377,14 @@ struct page *ext4_encrypt(struct inode *inode, 
 *

 * Return: Zero on success, non-zero otherwise.

 */

int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page)

int ext4_decrypt(struct page *page)

{

	BUG_ON(!PageLocked(page));



	return ext4_page_crypto(ctx, page->mapping->host,

	return ext4_page_crypto(page->mapping->host,

				EXT4_DECRYPT, page->index, page, page);

}



/*

 * Convenience function which takes care of allocating and

 * deallocating the encryption context

 */

int ext4_decrypt_one(struct inode *inode, struct page *page)

{

	int ret;



	struct ext4_crypto_ctx *ctx = ext4_get_crypto_ctx(inode);



	if (IS_ERR(ctx))

		return PTR_ERR(ctx);

	ret = ext4_decrypt(ctx, page);

	ext4_release_crypto_ctx(ctx);

	return ret;

}



int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)

{

	struct ext4_crypto_ctx	*ctx;
@@ -426,7 +408,7 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex) 
	}



	while (len--) {

		err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, lblk,

		err = ext4_page_crypto(inode, EXT4_ENCRYPT, lblk,

				       ZERO_PAGE(0), ciphertext_page);

		if (err)

			goto errout;

fs/ext4/ext4.h

+1 −2
Original line number Diff line number Diff line
@@ -2065,8 +2065,7 @@ 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);

int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page);

int ext4_decrypt_one(struct inode *inode, struct page *page);

int ext4_decrypt(struct page *page);

int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);



#ifdef CONFIG_EXT4_FS_ENCRYPTION

fs/ext4/inode.c

+2 −2
Original line number Diff line number Diff line
@@ -961,7 +961,7 @@ 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_one(inode, page);

		err = ext4_decrypt(page);

	return err;

}

#endif
@@ -3401,7 +3401,7 @@ static int ext4_block_zero_page_range(handle_t *handle, 
			/* We expect the key to be set. */

			BUG_ON(!ext4_has_encryption_key(inode));

			BUG_ON(blocksize != PAGE_CACHE_SIZE);

			WARN_ON_ONCE(ext4_decrypt_one(inode, page));

			WARN_ON_ONCE(ext4_decrypt(page));

		}

	}

	if (ext4_should_journal_data(inode)) {

fs/ext4/readpage.c

+1 −1
Original line number Diff line number Diff line
@@ -62,7 +62,7 @@ static void completion_pages(struct work_struct *work) 
	bio_for_each_segment_all(bv, bio, i) {

		struct page *page = bv->bv_page;



		int ret = ext4_decrypt(ctx, page);

		int ret = ext4_decrypt(page);

		if (ret) {

			WARN_ON_ONCE(1);

			SetPageError(page);