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 <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Christoph Hellwig 2010-06-08 18:14:43 +02:00 коммит произвёл Jens Axboe
Родитель 7f0e7bed93
Коммит 3c4d716538
1 изменённых файлов: 21 добавлений и 19 удалений

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@ -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);