From 500b067c5e6ceea49cf280a02597b1169320e08c Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 9 Sep 2009 09:10:25 +0200 Subject: [PATCH] writeback: check for registered bdi in flusher add and inode dirty Also a debugging aid. We want to catch dirty inodes being added to backing devices that don't do writeback. Signed-off-by: Jens Axboe --- fs/fs-writeback.c | 8 ++++++++ include/linux/backing-dev.h | 1 + mm/backing-dev.c | 7 +++++++ 3 files changed, 16 insertions(+) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 2e601ce581c9..da86ef58e427 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1046,6 +1046,14 @@ void __mark_inode_dirty(struct inode *inode, int flags) */ if (!was_dirty) { struct bdi_writeback *wb = &inode_to_bdi(inode)->wb; + struct backing_dev_info *bdi = wb->bdi; + + if (bdi_cap_writeback_dirty(bdi) && + !test_bit(BDI_registered, &bdi->state)) { + WARN_ON(1); + printk(KERN_ERR "bdi-%s not registered\n", + bdi->name); + } inode->dirtied_when = jiffies; list_move(&inode->i_list, &wb->b_dirty); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 2f218b7cb063..f169bcb90b58 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -29,6 +29,7 @@ enum bdi_state { BDI_wb_alloc, /* Default embedded wb allocated */ BDI_async_congested, /* The async (write) queue is getting full */ BDI_sync_congested, /* The sync queue is getting full */ + BDI_registered, /* bdi_register() was done */ BDI_unused, /* Available bits start here */ }; diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 5cb32c5b93d8..d3ca0dac1111 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -465,6 +465,12 @@ void static bdi_add_default_flusher_task(struct backing_dev_info *bdi) if (!bdi_cap_writeback_dirty(bdi)) return; + if (WARN_ON(!test_bit(BDI_registered, &bdi->state))) { + printk(KERN_ERR "bdi %p/%s is not registered!\n", + bdi, bdi->name); + return; + } + /* * Check with the helper whether to proceed adding a task. Will only * abort if we two or more simultanous calls to @@ -528,6 +534,7 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent, } bdi_debug_register(bdi, dev_name(dev)); + set_bit(BDI_registered, &bdi->state); exit: return ret; } -- 2.20.1