btrfs: scrub: use bool for flush_all_writes

flush_all_writes is an atomic but does not use the semantics at all,
it's just on/off indicator, we can use bool.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/scrub.c

@@ -182,8 +182,8 @@ struct scrub_ctx {
 	struct scrub_bio        *wr_curr_bio;
 	struct mutex            wr_lock;
 	int                     pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
-	atomic_t                flush_all_writes;
 	struct btrfs_device     *wr_tgtdev;
+	bool                    flush_all_writes;
 
 	/*
 	 * statistics
@@ -717,7 +717,7 @@ struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
 		WARN_ON(!fs_info->dev_replace.tgtdev);
 		sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
 		sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
-		atomic_set(&sctx->flush_all_writes, 0);
+		sctx->flush_all_writes = false;
 	}
 
 	return sctx;
@@ -2402,8 +2402,7 @@ static void scrub_missing_raid56_worker(struct btrfs_work *work)
 
 	scrub_block_put(sblock);
 
-	if (sctx->is_dev_replace &&
-	    atomic_read(&sctx->flush_all_writes)) {
+	if (sctx->is_dev_replace && sctx->flush_all_writes) {
 		mutex_lock(&sctx->wr_lock);
 		scrub_wr_submit(sctx);
 		mutex_unlock(&sctx->wr_lock);
@@ -2607,8 +2606,7 @@ static void scrub_bio_end_io_worker(struct btrfs_work *work)
 	sctx->first_free = sbio->index;
 	spin_unlock(&sctx->list_lock);
 
-	if (sctx->is_dev_replace &&
-	    atomic_read(&sctx->flush_all_writes)) {
+	if (sctx->is_dev_replace && sctx->flush_all_writes) {
 		mutex_lock(&sctx->wr_lock);
 		scrub_wr_submit(sctx);
 		mutex_unlock(&sctx->wr_lock);
@@ -3440,14 +3438,14 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 		 */
 		if (atomic_read(&fs_info->scrub_pause_req)) {
 			/* push queued extents */
-			atomic_set(&sctx->flush_all_writes, 1);
+			sctx->flush_all_writes = true;
 			scrub_submit(sctx);
 			mutex_lock(&sctx->wr_lock);
 			scrub_wr_submit(sctx);
 			mutex_unlock(&sctx->wr_lock);
 			wait_event(sctx->list_wait,
 				   atomic_read(&sctx->bios_in_flight) == 0);
-			atomic_set(&sctx->flush_all_writes, 0);
+			sctx->flush_all_writes = false;
 			scrub_blocked_if_needed(fs_info);
 		}
 
@@ -3892,7 +3890,7 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 		 * write requests are really completed when bios_in_flight
 		 * changes to 0.
 		 */
-		atomic_set(&sctx->flush_all_writes, 1);
+		sctx->flush_all_writes = true;
 		scrub_submit(sctx);
 		mutex_lock(&sctx->wr_lock);
 		scrub_wr_submit(sctx);
@@ -3910,7 +3908,7 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 		 */
 		wait_event(sctx->list_wait,
 			   atomic_read(&sctx->workers_pending) == 0);
-		atomic_set(&sctx->flush_all_writes, 0);
+		sctx->flush_all_writes = false;
 
 		scrub_pause_off(fs_info);