From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Thu, 5 Aug 2021 17:02:39 +0000 (-0400)
Subject: bcachefs: Fix an unhandled transaction restart
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=3737e0ddfbce4791a6415fa685e235b03924ff01;p=linux.git

bcachefs: Fix an unhandled transaction restart

__bch2_read() -> __bch2_read_extent() -> bch2_bucket_io_time_reset() may
cause a transaction restart, which we don't return an error for because
it doesn't prevent us from making forward progress on the read we're
submitting.

Instead, change __bch2_read() and bchfs_read() to check for transaction
restarts.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
---

diff --git a/fs/bcachefs/fs-io.c b/fs/bcachefs/fs-io.c
index 30e5acd2e97c4..9ac10b72d1cf0 100644
--- a/fs/bcachefs/fs-io.c
+++ b/fs/bcachefs/fs-io.c
@@ -791,6 +791,15 @@ retry:
 		unsigned bytes, sectors, offset_into_extent;
 		enum btree_id data_btree = BTREE_ID_extents;
 
+		/*
+		 * read_extent -> io_time_reset may cause a transaction restart
+		 * without returning an error, we need to check for that here:
+		 */
+		if (!bch2_trans_relock(trans)) {
+			ret = -EINTR;
+			break;
+		}
+
 		bch2_btree_iter_set_pos(iter,
 				POS(inum, rbio->bio.bi_iter.bi_sector));
 
diff --git a/fs/bcachefs/io.c b/fs/bcachefs/io.c
index f293876e0bbc0..30d9b6e4abf74 100644
--- a/fs/bcachefs/io.c
+++ b/fs/bcachefs/io.c
@@ -2288,6 +2288,15 @@ retry:
 		unsigned bytes, sectors, offset_into_extent;
 		enum btree_id data_btree = BTREE_ID_extents;
 
+		/*
+		 * read_extent -> io_time_reset may cause a transaction restart
+		 * without returning an error, we need to check for that here:
+		 */
+		if (!bch2_trans_relock(&trans)) {
+			ret = -EINTR;
+			break;
+		}
+
 		bch2_btree_iter_set_pos(iter,
 				POS(inode, bvec_iter.bi_sector));