diff options
author | Tejun Heo <tj@kernel.org> | 2014-09-08 08:04:01 +0900 |
---|---|---|
committer | Jens Axboe <axboe@fb.com> | 2014-09-08 10:00:43 -0600 |
commit | 018a17bdc8658ad448497c84d4ba21b6985820ec (patch) | |
tree | 77bfb4ea1b75452dd68817d59770e8d1c6bd37ec /fs | |
parent | 1a1e4530eacca37e85a4d66a164273c7dba9110c (diff) |
bdi: reimplement bdev_inode_switch_bdi()
A block_device may be attached to different gendisks and thus
different bdis over time. bdev_inode_switch_bdi() is used to switch
the associated bdi. The function assumes that the inode could be
dirty and transfers it between bdis if so. This is a bit nasty in
that it reaches into bdi internals.
This patch reimplements the function so that it writes out the inode
if dirty. This is a lot simpler and can be implemented without
exposing bdi internals.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/block_dev.c | 32 |
1 files changed, 11 insertions, 21 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index d3251eca6429..cc8d68ac29aa 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -50,32 +50,22 @@ inline struct block_device *I_BDEV(struct inode *inode) EXPORT_SYMBOL(I_BDEV); /* - * Move the inode from its current bdi to a new bdi. If the inode is dirty we - * need to move it onto the dirty list of @dst so that the inode is always on - * the right list. + * Move the inode from its current bdi to a new bdi. Make sure the inode + * is clean before moving so that it doesn't linger on the old bdi. */ static void bdev_inode_switch_bdi(struct inode *inode, struct backing_dev_info *dst) { - struct backing_dev_info *old = inode->i_data.backing_dev_info; - bool wakeup_bdi = false; - - if (unlikely(dst == old)) /* deadlock avoidance */ - return; - bdi_lock_two(&old->wb, &dst->wb); - spin_lock(&inode->i_lock); - inode->i_data.backing_dev_info = dst; - if (inode->i_state & I_DIRTY) { - if (bdi_cap_writeback_dirty(dst) && !wb_has_dirty_io(&dst->wb)) - wakeup_bdi = true; - list_move(&inode->i_wb_list, &dst->wb.b_dirty); + while (true) { + spin_lock(&inode->i_lock); + if (!(inode->i_state & I_DIRTY)) { + inode->i_data.backing_dev_info = dst; + spin_unlock(&inode->i_lock); + return; + } + spin_unlock(&inode->i_lock); + WARN_ON_ONCE(write_inode_now(inode, true)); } - spin_unlock(&inode->i_lock); - spin_unlock(&old->wb.list_lock); - spin_unlock(&dst->wb.list_lock); - - if (wakeup_bdi) - bdi_wakeup_thread_delayed(dst); } /* Kill _all_ buffers and pagecache , dirty or not.. */ |