writeback: pass in super_block to bdi_start_writeback()
Sometimes we only want to write pages from a specific super_block,
so allow that to be passed in.
This fixes a problem with commit 56a131dcf7ed36c3c6e36bea448b674ea85ed5bb
causing writeback on all super_blocks on a bdi, where we only really
want to sync a specific sb from writeback_inodes_sb().
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index fb61178c..9d5360c 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -250,9 +250,11 @@
* completion. Caller need not hold sb s_umount semaphore.
*
*/
-void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages)
+void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
+ long nr_pages)
{
struct wb_writeback_args args = {
+ .sb = sb,
.sync_mode = WB_SYNC_NONE,
.nr_pages = nr_pages,
.range_cyclic = 1,
@@ -1206,7 +1208,7 @@
nr_to_write = nr_dirty + nr_unstable +
(inodes_stat.nr_inodes - inodes_stat.nr_unused);
- bdi_start_writeback(sb->s_bdi, nr_to_write);
+ bdi_start_writeback(sb->s_bdi, sb, nr_to_write);
}
EXPORT_SYMBOL(writeback_inodes_sb);
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index 0ee33c2..b449e73 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -101,7 +101,8 @@
const char *fmt, ...);
int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
void bdi_unregister(struct backing_dev_info *bdi);
-void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);
+void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
+ long nr_pages);
int bdi_writeback_task(struct bdi_writeback *wb);
int bdi_has_dirty_io(struct backing_dev_info *bdi);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 69b5fba..a3b1409 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -596,7 +596,7 @@
(!laptop_mode && ((global_page_state(NR_FILE_DIRTY)
+ global_page_state(NR_UNSTABLE_NFS))
> background_thresh)))
- bdi_start_writeback(bdi, 0);
+ bdi_start_writeback(bdi, NULL, 0);
}
void set_page_dirty_balance(struct page *page, int page_mkwrite)
