[PATCH 09/16] f2fs: Remove fs-layer file contents en/decryption code

[Eric Biggers <ebiggers@kernel.org>]

Now that fscrypt's file contents en/decryption is always implemented
using blk-crypto when the filesystem is block-based, the fs-layer
en/decryption code in f2fs is unused code.  Remove it.

Note that the struct f2fs_io_info field encrypted_page is kept because
it is still used by the garbage collection path to relocate encrypted
blocks using raw meta pages from META_MAPPING.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
 fs/f2fs/compress.c | 28 ++------------
 fs/f2fs/data.c     | 93 +++++-----------------------------------------
 fs/f2fs/f2fs.h     |  2 -
 fs/f2fs/segment.c  |  2 -
 fs/f2fs/super.c    |  1 -
 5 files changed, 12 insertions(+), 114 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 881e76158b96..e0ad9ba315b4 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -1282,12 +1282,10 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 		.page = NULL,
 		.encrypted_page = NULL,
 		.compressed_page = NULL,
 		.io_type = io_type,
 		.io_wbc = wbc,
-		.encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode) ?
-									1 : 0,
 	};
 	struct folio *folio;
 	struct dnode_of_data dn;
 	struct node_info ni;
 	struct compress_io_ctx *cic;
@@ -1357,18 +1355,10 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 		fio.old_blkaddr = data_blkaddr(dn.inode, dn.node_folio,
 						dn.ofs_in_node + i + 1);
 
 		/* wait for GCed page writeback via META_MAPPING */
 		f2fs_wait_on_block_writeback(inode, fio.old_blkaddr);
-
-		if (fio.encrypted) {
-			fio.page = cc->rpages[i + 1];
-			err = f2fs_encrypt_one_page(&fio);
-			if (err)
-				goto out_destroy_crypt;
-			cc->cpages[i] = fio.encrypted_page;
-		}
 	}
 
 	set_cluster_writeback(cc);
 
 	for (i = 0; i < cc->cluster_size; i++)
@@ -1402,25 +1392,19 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 			goto unlock_continue;
 		}
 
 		f2fs_bug_on(fio.sbi, blkaddr == NULL_ADDR);
 
-		if (fio.encrypted)
-			fio.encrypted_page = cc->cpages[i - 1];
-		else
-			fio.compressed_page = cc->cpages[i - 1];
+		fio.compressed_page = cc->cpages[i - 1];
 
 		cc->cpages[i - 1] = NULL;
 		fio.submitted = 0;
 		f2fs_outplace_write_data(&dn, &fio);
 		if (unlikely(!fio.submitted)) {
 			cancel_cluster_writeback(cc, cic, i);
-
-			/* To call fscrypt_finalize_bounce_page */
-			i = cc->valid_nr_cpages;
 			*submitted = 0;
-			goto out_destroy_crypt;
+			goto out_free_page_array;
 		}
 		(*submitted)++;
 unlock_continue:
 		inode_dec_dirty_pages(cc->inode);
 		folio_unlock(fio.folio);
@@ -1448,18 +1432,12 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 	page_array_free(sbi, cc->cpages, cc->nr_cpages);
 	cc->cpages = NULL;
 	f2fs_destroy_compress_ctx(cc, false);
 	return 0;
 
-out_destroy_crypt:
+out_free_page_array:
 	page_array_free(sbi, cic->rpages, cc->cluster_size);
-
-	for (--i; i >= 0; i--) {
-		if (!cc->cpages[i])
-			continue;
-		fscrypt_finalize_bounce_page(&cc->cpages[i]);
-	}
 out_put_cic:
 	kmem_cache_free(cic_entry_slab, cic);
 out_put_dnode:
 	f2fs_put_dnode(&dn);
 out_unlock_op:
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 8d4f1e75dee3..315bfe40da87 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -57,13 +57,10 @@ bool f2fs_is_cp_guaranteed(const struct folio *folio)
 {
 	struct address_space *mapping = folio->mapping;
 	struct inode *inode;
 	struct f2fs_sb_info *sbi;
 
-	if (fscrypt_is_bounce_folio(folio))
-		return folio_test_f2fs_gcing(fscrypt_pagecache_folio(folio));
-
 	inode = mapping->host;
 	sbi = F2FS_I_SB(inode);
 
 	if (inode->i_ino == F2FS_META_INO(sbi) ||
 			inode->i_ino == F2FS_NODE_INO(sbi) ||
@@ -93,15 +90,10 @@ static enum count_type __read_io_type(struct folio *folio)
 	return F2FS_RD_DATA;
 }
 
 /* postprocessing steps for read bios */
 enum bio_post_read_step {
-#ifdef CONFIG_FS_ENCRYPTION
-	STEP_DECRYPT	= BIT(0),
-#else
-	STEP_DECRYPT	= 0,	/* compile out the decryption-related code */
-#endif
 #ifdef CONFIG_F2FS_FS_COMPRESSION
 	STEP_DECOMPRESS	= BIT(1),
 #else
 	STEP_DECOMPRESS	= 0,	/* compile out the decompression-related code */
 #endif
@@ -293,15 +285,10 @@ static void f2fs_post_read_work(struct work_struct *work)
 {
 	struct bio_post_read_ctx *ctx =
 		container_of(work, struct bio_post_read_ctx, work);
 	struct bio *bio = ctx->bio;
 
-	if ((ctx->enabled_steps & STEP_DECRYPT) && !fscrypt_decrypt_bio(bio)) {
-		f2fs_finish_read_bio(bio, true);
-		return;
-	}
-
 	if (ctx->enabled_steps & STEP_DECOMPRESS)
 		f2fs_handle_step_decompress(ctx, true);
 
 	f2fs_verify_and_finish_bio(bio, true);
 }
@@ -321,22 +308,15 @@ static void f2fs_read_end_io(struct bio *bio)
 	if (bio->bi_status != BLK_STS_OK) {
 		f2fs_finish_read_bio(bio, intask);
 		return;
 	}
 
-	if (ctx) {
-		unsigned int enabled_steps = ctx->enabled_steps &
-					(STEP_DECRYPT | STEP_DECOMPRESS);
-
-		/*
-		 * If we have only decompression step between decompression and
-		 * decrypt, we don't need post processing for this.
-		 */
-		if (enabled_steps == STEP_DECOMPRESS &&
-				!f2fs_low_mem_mode(sbi)) {
+	if (ctx && (ctx->enabled_steps & STEP_DECOMPRESS)) {
+		if (!f2fs_low_mem_mode(sbi)) {
+			/* Decompress inline. */
 			f2fs_handle_step_decompress(ctx, intask);
-		} else if (enabled_steps) {
+		} else {
 			INIT_WORK(&ctx->work, f2fs_post_read_work);
 			queue_work(ctx->sbi->post_read_wq, &ctx->work);
 			return;
 		}
 	}
@@ -357,17 +337,10 @@ static void f2fs_write_end_io(struct bio *bio)
 
 	bio_for_each_folio_all(fi, bio) {
 		struct folio *folio = fi.folio;
 		enum count_type type;
 
-		if (fscrypt_is_bounce_folio(folio)) {
-			struct folio *io_folio = folio;
-
-			folio = fscrypt_pagecache_folio(io_folio);
-			fscrypt_free_bounce_page(&io_folio->page);
-		}
-
 #ifdef CONFIG_F2FS_FS_COMPRESSION
 		if (f2fs_is_compressed_page(folio)) {
 			f2fs_compress_write_end_io(bio, folio);
 			continue;
 		}
@@ -599,15 +572,10 @@ static bool __has_merged_page(struct bio *bio, struct inode *inode,
 		return true;
 
 	bio_for_each_folio_all(fi, bio) {
 		struct folio *target = fi.folio;
 
-		if (fscrypt_is_bounce_folio(target)) {
-			target = fscrypt_pagecache_folio(target);
-			if (IS_ERR(target))
-				continue;
-		}
 		if (f2fs_is_compressed_page(target)) {
 			target = f2fs_compress_control_folio(target);
 			if (IS_ERR(target))
 				continue;
 		}
@@ -1117,13 +1085,10 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode,
 			       for_write ? GFP_NOIO : GFP_KERNEL, &f2fs_bioset);
 	bio->bi_iter.bi_sector = sector;
 	f2fs_set_bio_crypt_ctx(bio, inode, first_idx, NULL, GFP_NOFS);
 	bio->bi_end_io = f2fs_read_end_io;
 
-	if (fscrypt_inode_uses_fs_layer_crypto(inode))
-		post_read_steps |= STEP_DECRYPT;
-
 	if (vi)
 		post_read_steps |= STEP_VERITY;
 
 	/*
 	 * STEP_DECOMPRESS is handled specially, since a compressed file might
@@ -2808,39 +2773,10 @@ static void f2fs_readahead(struct readahead_control *rac)
 		fsverity_readahead(vi, readahead_index(rac),
 				   readahead_count(rac));
 	f2fs_mpage_readpages(inode, vi, rac, NULL);
 }
 
-int f2fs_encrypt_one_page(struct f2fs_io_info *fio)
-{
-	struct inode *inode = fio_inode(fio);
-	struct folio *mfolio;
-	struct page *page;
-
-	if (!f2fs_encrypted_file(inode))
-		return 0;
-
-	page = fio->compressed_page ? fio->compressed_page : fio->page;
-
-	if (fscrypt_inode_uses_inline_crypto(inode))
-		return 0;
-
-	fio->encrypted_page = fscrypt_encrypt_pagecache_blocks(page_folio(page),
-					PAGE_SIZE, 0, GFP_NOFS);
-	if (IS_ERR(fio->encrypted_page))
-		return PTR_ERR(fio->encrypted_page);
-
-	mfolio = filemap_lock_folio(META_MAPPING(fio->sbi), fio->old_blkaddr);
-	if (!IS_ERR(mfolio)) {
-		if (folio_test_uptodate(mfolio))
-			memcpy(folio_address(mfolio),
-				page_address(fio->encrypted_page), PAGE_SIZE);
-		f2fs_folio_put(mfolio, true);
-	}
-	return 0;
-}
-
 static inline bool check_inplace_update_policy(struct inode *inode,
 				struct f2fs_io_info *fio)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 
@@ -3009,26 +2945,19 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 	 * it had better in-place writes for updated data.
 	 */
 	if (ipu_force ||
 		(__is_valid_data_blkaddr(fio->old_blkaddr) &&
 					need_inplace_update(fio))) {
-		err = f2fs_encrypt_one_page(fio);
-		if (err)
-			goto out_writepage;
-
 		folio_start_writeback(folio);
 		f2fs_put_dnode(&dn);
 		if (fio->need_lock == LOCK_REQ)
 			f2fs_unlock_op(fio->sbi, &lc);
 		err = f2fs_inplace_write_data(fio);
-		if (err) {
-			if (fscrypt_inode_uses_fs_layer_crypto(inode))
-				fscrypt_finalize_bounce_page(&fio->encrypted_page);
+		if (err)
 			folio_end_writeback(folio);
-		} else {
+		else
 			set_inode_flag(inode, FI_UPDATE_WRITE);
-		}
 		trace_f2fs_do_write_data_page(folio, IPU);
 		return err;
 	}
 
 	if (fio->need_lock == LOCK_RETRY) {
@@ -3043,14 +2972,10 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 	if (err)
 		goto out_writepage;
 
 	fio->version = ni.version;
 
-	err = f2fs_encrypt_one_page(fio);
-	if (err)
-		goto out_writepage;
-
 	folio_start_writeback(folio);
 
 	if (fio->compr_blocks && fio->old_blkaddr == COMPRESS_ADDR)
 		f2fs_i_compr_blocks_update(inode, fio->compr_blocks - 1, false);
 
@@ -4547,13 +4472,13 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
 		return err;
 
 	iomap->offset = F2FS_BLK_TO_BYTES(map.m_lblk);
 
 	/*
-	 * When inline encryption is enabled, sometimes I/O to an encrypted file
-	 * has to be broken up to guarantee DUN contiguity.  Handle this by
-	 * limiting the length of the mapping returned.
+	 * Sometimes I/O to an encrypted file has to be broken up to guarantee
+	 * DUN contiguity.  Handle this by limiting the length of the mapping
+	 * returned.
 	 */
 	map.m_len = fscrypt_limit_io_blocks(inode, map.m_lblk, map.m_len);
 
 	/*
 	 * We should never see delalloc or compressed extents here based on
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 91f506e7c9cf..746e678ceb1a 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1353,11 +1353,10 @@ struct f2fs_io_info {
 	unsigned int need_lock:8;	/* indicate we need to lock cp_rwsem */
 	unsigned int version:8;		/* version of the node */
 	unsigned int submitted:1;	/* indicate IO submission */
 	unsigned int in_list:1;		/* indicate fio is in io_list */
 	unsigned int is_por:1;		/* indicate IO is from recovery or not */
-	unsigned int encrypted:1;	/* indicate file is encrypted */
 	unsigned int meta_gc:1;		/* require meta inode GC */
 	enum iostat_type io_type;	/* io type */
 	struct writeback_control *io_wbc; /* writeback control */
 	struct bio **bio;		/* bio for ipu */
 	sector_t *last_block;		/* last block number in bio */
@@ -4176,11 +4175,10 @@ struct folio *f2fs_get_new_data_folio(struct inode *inode,
 			struct folio *ifolio, pgoff_t index, bool new_i_size);
 int f2fs_do_write_data_page(struct f2fs_io_info *fio);
 int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag);
 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 			u64 start, u64 len);
-int f2fs_encrypt_one_page(struct f2fs_io_info *fio);
 bool f2fs_should_update_inplace(struct inode *inode, struct f2fs_io_info *fio);
 bool f2fs_should_update_outplace(struct inode *inode, struct f2fs_io_info *fio);
 int f2fs_write_single_data_page(struct folio *folio, int *submitted,
 				struct bio **bio, sector_t *last_block,
 				struct writeback_control *wbc,
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 788f8b050249..e45eb0ff961d 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3985,12 +3985,10 @@ static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
 	if (unlikely(err)) {
 		f2fs_err_ratelimited(fio->sbi,
 			"%s Failed to allocate data block, ino:%u, index:%lu, type:%d, old_blkaddr:0x%x, new_blkaddr:0x%x, err:%d",
 			__func__, fio->ino, folio->index, type,
 			fio->old_blkaddr, fio->new_blkaddr, err);
-		if (fscrypt_inode_uses_fs_layer_crypto(folio->mapping->host))
-			fscrypt_finalize_bounce_page(&fio->encrypted_page);
 		folio_end_writeback(folio);
 		if (f2fs_in_warm_node_list(folio))
 			f2fs_del_fsync_node_entry(fio->sbi, folio);
 		f2fs_bug_on(fio->sbi, !is_set_ckpt_flags(fio->sbi,
 							CP_ERROR_FLAG));
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index f3f6768f8cca..fd9d3ea4c058 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3753,11 +3753,10 @@ static struct block_device **f2fs_get_devices(struct super_block *sb,
 
 static const struct fscrypt_operations f2fs_cryptops = {
 	.inode_info_offs	= (int)offsetof(struct f2fs_inode_info, i_crypt_info) -
 				  (int)offsetof(struct f2fs_inode_info, vfs_inode),
 	.is_block_based		= 1,
-	.needs_bounce_pages	= 1,
 	.has_32bit_inodes	= 1,
 	.supports_subblock_data_units = 1,
 	.legacy_key_prefix	= "f2fs:",
 	.get_context		= f2fs_get_context,
 	.set_context		= f2fs_set_context,
-- 
2.54.0