ext4 crypto: migrate into vfs's crypto engine

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>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 6 insertions, 7 deletions

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 2a01df9cc1c3..5ad05af51dd8 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);
                 }
@@ -472,7 +471,7 @@ 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) {
@@ -510,7 +509,7 @@ 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 {