From 3c4d716538f3eefb1c1f10961a047a6456a2b590 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 8 Jun 2010 18:14:43 +0200 Subject: [PATCH] writeback: queue work on stack in writeback_inodes_sb If we want to rely on s_umount in the caller we need to wait for completion of the I/O submission before returning to the caller. Refactor bdi_sync_writeback into a bdi_queue_work_onstack helper and use it for this case. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- fs/fs-writeback.c | 40 +++++++++++++++++++++------------------- 1 file changed, 21 insertions(+), 19 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index dbf6f108e868..759666966c6d 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -178,30 +178,22 @@ static void bdi_alloc_queue_work(struct backing_dev_info *bdi, } /** - * bdi_sync_writeback - start and wait for writeback - * @bdi: the backing device to write from + * bdi_queue_work_onstack - start and wait for writeback * @sb: write inodes from this super_block * * Description: - * This does WB_SYNC_ALL data integrity writeback and waits for the - * IO to complete. Callers must hold the sb s_umount semaphore for + * This function initiates writeback and waits for the operation to + * complete. Callers must hold the sb s_umount semaphore for * reading, to avoid having the super disappear before we are done. */ -static void bdi_sync_writeback(struct backing_dev_info *bdi, - struct super_block *sb) +static void bdi_queue_work_onstack(struct wb_writeback_args *args) { - struct wb_writeback_args args = { - .sb = sb, - .sync_mode = WB_SYNC_ALL, - .nr_pages = LONG_MAX, - .range_cyclic = 0, - }; struct bdi_work work; - bdi_work_init(&work, &args); + bdi_work_init(&work, args); __set_bit(WS_ONSTACK, &work.state); - bdi_queue_work(bdi, &work); + bdi_queue_work(args->sb->s_bdi, &work); bdi_wait_on_work_done(&work); } @@ -944,7 +936,7 @@ int bdi_writeback_task(struct bdi_writeback *wb) /* * Schedule writeback for all backing devices. This does WB_SYNC_NONE - * writeback, for integrity writeback see bdi_sync_writeback(). + * writeback, for integrity writeback see bdi_queue_work_onstack(). */ static void bdi_writeback_all(struct super_block *sb, long nr_pages) { @@ -1183,12 +1175,15 @@ void writeback_inodes_sb(struct super_block *sb) { unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY); unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS); - long nr_to_write; + struct wb_writeback_args args = { + .sb = sb, + .sync_mode = WB_SYNC_NONE, + }; - nr_to_write = nr_dirty + nr_unstable + + args.nr_pages = nr_dirty + nr_unstable + (inodes_stat.nr_inodes - inodes_stat.nr_unused); - bdi_start_writeback(sb->s_bdi, sb, nr_to_write); + bdi_queue_work_onstack(&args); } EXPORT_SYMBOL(writeback_inodes_sb); @@ -1218,7 +1213,14 @@ EXPORT_SYMBOL(writeback_inodes_sb_if_idle); */ void sync_inodes_sb(struct super_block *sb) { - bdi_sync_writeback(sb->s_bdi, sb); + struct wb_writeback_args args = { + .sb = sb, + .sync_mode = WB_SYNC_ALL, + .nr_pages = LONG_MAX, + .range_cyclic = 0, + }; + + bdi_queue_work_onstack(&args); wait_sb_inodes(sb); } EXPORT_SYMBOL(sync_inodes_sb); -- 2.20.1