Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index 9a6bc09..4fc87de 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -63,10 +63,31 @@
* so it has a mismatch name.
*/
WB_REASON_FORKER_THREAD,
+ WB_REASON_FOREIGN_FLUSH,
WB_REASON_MAX,
};
+struct wb_completion {
+ atomic_t cnt;
+ wait_queue_head_t *waitq;
+};
+
+#define __WB_COMPLETION_INIT(_waitq) \
+ (struct wb_completion){ .cnt = ATOMIC_INIT(1), .waitq = (_waitq) }
+
+/*
+ * If one wants to wait for one or more wb_writeback_works, each work's
+ * ->done should be set to a wb_completion defined using the following
+ * macro. Once all work items are issued with wb_queue_work(), the caller
+ * can wait for the completion of all using wb_wait_for_completion(). Work
+ * items which are waited upon aren't freed automatically on completion.
+ */
+#define WB_COMPLETION_INIT(bdi) __WB_COMPLETION_INIT(&(bdi)->wb_waitq)
+
+#define DEFINE_WB_COMPLETION(cmpl, bdi) \
+ struct wb_completion cmpl = WB_COMPLETION_INIT(bdi)
+
/*
* For cgroup writeback, multiple wb's may map to the same blkcg. Those
* wb's can operate mostly independently but should share the congested
@@ -165,6 +186,8 @@
};
struct backing_dev_info {
+ u64 id;
+ struct rb_node rb_node; /* keyed by ->id */
struct list_head bdi_list;
unsigned long ra_pages; /* max readahead in PAGE_SIZE units */
unsigned long io_pages; /* max allowed IO size */
@@ -190,6 +213,7 @@
struct radix_tree_root cgwb_tree; /* radix tree of active cgroup wbs */
struct rb_root cgwb_congested_tree; /* their congested states */
struct mutex cgwb_release_mutex; /* protect shutdown of wb structs */
+ struct rw_semaphore wb_switch_rwsem; /* no cgwb switch while syncing */
#else
struct bdi_writeback_congested *wb_congested;
#endif
@@ -202,7 +226,6 @@
#ifdef CONFIG_DEBUG_FS
struct dentry *debug_dir;
- struct dentry *debug_stats;
#endif
};
@@ -258,6 +281,14 @@
*/
static inline void wb_put(struct bdi_writeback *wb)
{
+ if (WARN_ON_ONCE(!wb->bdi)) {
+ /*
+ * A driver bug might cause a file to be removed before bdi was
+ * initialized.
+ */
+ return;
+ }
+
if (wb != &wb->bdi->wb)
percpu_ref_put(&wb->refcnt);
}