bcachefs: Drop old maybe_extending optimization

The extend update path had an optimization to avoid updating the inode
if we knew we were definitely not extending the file. But now that we're
updating inodes on every extent update - for fsync - that code can be
deleted.

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

3 files changed, 13 insertions, 74 deletions

diff --git a/fs/bcachefs/io.c b/fs/bcachefs/io.c
index 7c9ea91d8f5b..3bd1054aafa1 100644
--- a/fs/bcachefs/io.c
+++ b/fs/bcachefs/io.c
@@ -187,7 +187,6 @@ void bch2_bio_alloc_pages_pool(struct bch_fs *c, struct bio *bio,
 int bch2_sum_sector_overwrites(struct btree_trans *trans,
 			       struct btree_iter *extent_iter,
 			       struct bkey_i *new,
-			       bool *maybe_extending,
 			       bool *usage_increasing,
 			       s64 *i_sectors_delta,
 			       s64 *disk_sectors_delta)
@@ -199,7 +198,6 @@ int bch2_sum_sector_overwrites(struct btree_trans *trans,
 	bool new_compressed = bch2_bkey_sectors_compressed(bkey_i_to_s_c(new));
 	int ret = 0;
 
-	*maybe_extending	= true;
 	*usage_increasing	= false;
 	*i_sectors_delta	= 0;
 	*disk_sectors_delta	= 0;
@@ -226,31 +224,8 @@ int bch2_sum_sector_overwrites(struct btree_trans *trans,
 		     (!new_compressed && bch2_bkey_sectors_compressed(old))))
 			*usage_increasing = true;
 
-		if (bkey_cmp(old.k->p, new->k.p) >= 0) {
-			/*
-			 * Check if there's already data above where we're
-			 * going to be writing to - this means we're definitely
-			 * not extending the file:
-			 *
-			 * Note that it's not sufficient to check if there's
-			 * data up to the sector offset we're going to be
-			 * writing to, because i_size could be up to one block
-			 * less:
-			 */
-			if (!bkey_cmp(old.k->p, new->k.p)) {
-				old = bch2_btree_iter_next(&iter);
-				ret = bkey_err(old);
-				if (ret)
-					break;
-			}
-
-			if (old.k && !bkey_err(old) &&
-			    old.k->p.inode == extent_iter->pos.inode &&
-			    bkey_extent_is_data(old.k))
-				*maybe_extending = false;
-
+		if (bkey_cmp(old.k->p, new->k.p) >= 0)
 			break;
-		}
 	}
 
 	bch2_trans_iter_exit(trans, &iter);
@@ -267,12 +242,10 @@ int bch2_extent_update(struct btree_trans *trans,
 		       s64 *i_sectors_delta_total,
 		       bool check_enospc)
 {
-	/* this must live until after bch2_trans_commit(): */
-	struct bkey_inode_buf inode_p;
 	struct btree_iter inode_iter;
 	struct bch_inode_unpacked inode_u;
 	struct bpos next_pos;
-	bool extending = false, usage_increasing;
+	bool usage_increasing;
 	s64 i_sectors_delta = 0, disk_sectors_delta = 0;
 	int ret;
 
@@ -290,84 +263,51 @@ int bch2_extent_update(struct btree_trans *trans,
 	if (ret)
 		return ret;
 
+	new_i_size = min(k->k.p.offset << 9, new_i_size);
+	next_pos = k->k.p;
+
 	ret = bch2_sum_sector_overwrites(trans, iter, k,
-			&extending,
 			&usage_increasing,
 			&i_sectors_delta,
 			&disk_sectors_delta);
 	if (ret)
 		return ret;
 
-	if (!usage_increasing)
-		check_enospc = false;
-
 	if (disk_res &&
 	    disk_sectors_delta > (s64) disk_res->sectors) {
 		ret = bch2_disk_reservation_add(trans->c, disk_res,
 					disk_sectors_delta - disk_res->sectors,
-					!check_enospc
+					!check_enospc || !usage_increasing
 					? BCH_DISK_RESERVATION_NOFAIL : 0);
 		if (ret)
 			return ret;
 	}
 
-	new_i_size = extending
-		? min(k->k.p.offset << 9, new_i_size)
-		: 0;
-
 	ret = bch2_inode_peek(trans, &inode_iter, &inode_u, inum,
 			      BTREE_ITER_INTENT);
 	if (ret)
 		return ret;
 
-	/*
-	 * XXX:
-	 * writeback can race a bit with truncate, because truncate
-	 * first updates the inode then truncates the pagecache. This is
-	 * ugly, but lets us preserve the invariant that the in memory
-	 * i_size is always >= the on disk i_size.
-	 *
-	BUG_ON(new_i_size > inode_u.bi_size &&
-	       (inode_u.bi_flags & BCH_INODE_I_SIZE_DIRTY));
-	 */
-	BUG_ON(new_i_size > inode_u.bi_size && !extending);
-
 	if (!(inode_u.bi_flags & BCH_INODE_I_SIZE_DIRTY) &&
 	    new_i_size > inode_u.bi_size)
 		inode_u.bi_size = new_i_size;
-	else
-		new_i_size = 0;
 
 	inode_u.bi_sectors += i_sectors_delta;
 
-	if (i_sectors_delta || new_i_size) {
-		bch2_inode_pack(trans->c, &inode_p, &inode_u);
-
-		inode_p.inode.k.p.snapshot = iter->snapshot;
-
-		ret = bch2_trans_update(trans, &inode_iter,
-				  &inode_p.inode.k_i, 0);
-	}
-
-	bch2_trans_iter_exit(trans, &inode_iter);
-
-	if (ret)
-		return ret;
-
-	next_pos = k->k.p;
-
 	ret =   bch2_trans_update(trans, iter, k, 0) ?:
+		bch2_inode_write(trans, &inode_iter, &inode_u) ?:
 		bch2_trans_commit(trans, disk_res, journal_seq,
 				BTREE_INSERT_NOCHECK_RW|
 				BTREE_INSERT_NOFAIL);
-	BUG_ON(ret == -ENOSPC);
+	bch2_trans_iter_exit(trans, &inode_iter);
+
 	if (ret)
 		return ret;
 
-	bch2_btree_iter_set_pos(iter, next_pos);
-
 	if (i_sectors_delta_total)
 		*i_sectors_delta_total += i_sectors_delta;
+	bch2_btree_iter_set_pos(iter, next_pos);
+
 	return 0;
 }
 
diff --git a/fs/bcachefs/io.h b/fs/bcachefs/io.h
index fbe46660662b..1aa422dccef7 100644
--- a/fs/bcachefs/io.h
+++ b/fs/bcachefs/io.h
@@ -56,7 +56,7 @@ static inline struct workqueue_struct *index_update_wq(struct bch_write_op *op)
 }
 
 int bch2_sum_sector_overwrites(struct btree_trans *, struct btree_iter *,
-			       struct bkey_i *, bool *, bool *, s64 *, s64 *);
+			       struct bkey_i *, bool *, s64 *, s64 *);
 int bch2_extent_update(struct btree_trans *, subvol_inum,
 		       struct btree_iter *, struct bkey_i *,
 		       struct disk_reservation *, u64 *, u64, s64 *, bool);
diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 0152fbcde3c2..64e39c10e34b 100644
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -160,7 +160,7 @@ static int bch2_migrate_index_update(struct bch_write_op *op)
 		struct extent_ptr_decoded p;
 		struct bpos next_pos;
 		bool did_work = false;
-		bool extending = false, should_check_enospc;
+		bool should_check_enospc;
 		s64 i_sectors_delta = 0, disk_sectors_delta = 0;
 
 		bch2_trans_begin(&trans);
@@ -226,7 +226,6 @@ static int bch2_migrate_index_update(struct bch_write_op *op)
 					       op->opts.data_replicas);
 
 		ret = bch2_sum_sector_overwrites(&trans, &iter, insert,
-						 &extending,
 						 &should_check_enospc,
 						 &i_sectors_delta,
 						 &disk_sectors_delta);