linux-ext4 - [PATCH 13/16] ext4: consolidate fsverity

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Message-ID: <20260126045212.1381843-14-hch@lst.de>
Date: Mon, 26 Jan 2026 05:50:59 +0100
From: Christoph Hellwig <hch@....de>
To: Eric Biggers <ebiggers@...nel.org>
Cc: Al Viro <viro@...iv.linux.org.uk>,
	Christian Brauner <brauner@...nel.org>,
	Jan Kara <jack@...e.cz>,
	David Sterba <dsterba@...e.com>,
	"Theodore Ts'o" <tytso@....edu>,
	Jaegeuk Kim <jaegeuk@...nel.org>,
	Chao Yu <chao@...nel.org>,
	Andrey Albershteyn <aalbersh@...hat.com>,
	Matthew Wilcox <willy@...radead.org>,
	linux-fsdevel@...r.kernel.org,
	linux-btrfs@...r.kernel.org,
	linux-ext4@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net,
	fsverity@...ts.linux.dev,
	"Darrick J. Wong" <djwong@...nel.org>
Subject: [PATCH 13/16] ext4: consolidate fsverity_info lookup

Look up the fsverity_info once in ext4_mpage_readpages, and then use it
for the readahead, local verification of holes and pass it along to the
I/O completion workqueue in struct bio_post_read_ctx.

This amortizes the lookup better once it becomes less efficient.

Signed-off-by: Christoph Hellwig <hch@....de>
Reviewed-by: "Darrick J. Wong" <djwong@...nel.org>
---
 fs/ext4/readpage.c | 32 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index bf65562da9c2..17920f14e2c2 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -61,6 +61,7 @@ enum bio_post_read_step {
 
 struct bio_post_read_ctx {
 	struct bio *bio;
+	struct fsverity_info *vi;
 	struct work_struct work;
 	unsigned int cur_step;
 	unsigned int enabled_steps;
@@ -96,7 +97,7 @@ static void verity_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;
-	struct inode *inode = bio_first_folio_all(bio)->mapping->host;
+	struct fsverity_info *vi = ctx->vi;
 
 	/*
 	 * fsverity_verify_bio() may call readahead() again, and although verity
@@ -109,7 +110,7 @@ static void verity_work(struct work_struct *work)
 	mempool_free(ctx, bio_post_read_ctx_pool);
 	bio->bi_private = NULL;
 
-	fsverity_verify_bio(*fsverity_info_addr(inode), bio);
+	fsverity_verify_bio(vi, bio);
 
 	__read_end_io(bio);
 }
@@ -173,22 +174,16 @@ static void mpage_end_io(struct bio *bio)
 	__read_end_io(bio);
 }
 
-static inline bool ext4_need_verity(const struct inode *inode, pgoff_t idx)
-{
-	return fsverity_active(inode) &&
-	       idx < DIV_ROUND_UP(inode->i_size, PAGE_SIZE);
-}
-
 static void ext4_set_bio_post_read_ctx(struct bio *bio,
 				       const struct inode *inode,
-				       pgoff_t first_idx)
+				       struct fsverity_info *vi)
 {
 	unsigned int post_read_steps = 0;
 
 	if (fscrypt_inode_uses_fs_layer_crypto(inode))
 		post_read_steps |= 1 << STEP_DECRYPT;
 
-	if (ext4_need_verity(inode, first_idx))
+	if (vi)
 		post_read_steps |= 1 << STEP_VERITY;
 
 	if (post_read_steps) {
@@ -197,6 +192,7 @@ static void ext4_set_bio_post_read_ctx(struct bio *bio,
 			mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS);
 
 		ctx->bio = bio;
+		ctx->vi = vi;
 		ctx->enabled_steps = post_read_steps;
 		bio->bi_private = ctx;
 	}
@@ -224,6 +220,7 @@ int ext4_mpage_readpages(struct inode *inode,
 	sector_t first_block;
 	unsigned page_block;
 	struct block_device *bdev = inode->i_sb->s_bdev;
+	struct fsverity_info *vi = NULL;
 	int length;
 	unsigned relative_block = 0;
 	struct ext4_map_blocks map;
@@ -245,9 +242,11 @@ int ext4_mpage_readpages(struct inode *inode,
 			folio = readahead_folio(rac);
 
 		if (first_folio) {
-			if (ext4_need_verity(inode, folio->index))
-				fsverity_readahead(*fsverity_info_addr(inode),
-						folio, nr_pages);
+			if (folio->index <
+			    DIV_ROUND_UP(inode->i_size, PAGE_SIZE))
+				vi = fsverity_get_info(inode);
+			if (vi)
+				fsverity_readahead(vi, folio, nr_pages);
 			first_folio = false;
 		}
 
@@ -338,10 +337,7 @@ int ext4_mpage_readpages(struct inode *inode,
 			folio_zero_segment(folio, first_hole << blkbits,
 					  folio_size(folio));
 			if (first_hole == 0) {
-				if (ext4_need_verity(inode, folio->index) &&
-				    !fsverity_verify_folio(
-						*fsverity_info_addr(inode),
-						folio))
+				if (vi && !fsverity_verify_folio(vi, folio))
 					goto set_error_page;
 				folio_end_read(folio, true);
 				continue;
@@ -369,7 +365,7 @@ int ext4_mpage_readpages(struct inode *inode,
 					REQ_OP_READ, GFP_KERNEL);
 			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
 						  GFP_KERNEL);
-			ext4_set_bio_post_read_ctx(bio, inode, folio->index);
+			ext4_set_bio_post_read_ctx(bio, inode, vi);
 			bio->bi_iter.bi_sector = first_block << (blkbits - 9);
 			bio->bi_end_io = mpage_end_io;
 			if (rac)
-- 
2.47.3