From 1eb787ec183d1267cac95aae632e92dee05ed50a Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 9 Apr 2009 00:27:14 +0100 Subject: [PATCH] dm: split DMF_BLOCK_IO flag into two Split the DMF_BLOCK_IO flag into two. DMF_BLOCK_IO_FOR_SUSPEND is set when I/O must be blocked while suspending a device. DMF_QUEUE_IO_TO_THREAD is set when I/O must be queued to a worker thread for later processing. Signed-off-by: Alasdair G Kergon --- drivers/md/dm.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 020a9e1993a7..7cac7220937f 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -89,12 +89,13 @@ union map_info *dm_get_mapinfo(struct bio *bio) /* * Bits for the md->flags field. */ -#define DMF_BLOCK_IO 0 +#define DMF_BLOCK_IO_FOR_SUSPEND 0 #define DMF_SUSPENDED 1 #define DMF_FROZEN 2 #define DMF_FREEING 3 #define DMF_DELETING 4 #define DMF_NOFLUSH_SUSPENDING 5 +#define DMF_QUEUE_IO_TO_THREAD 6 /* * Work processed by per-device workqueue. @@ -439,7 +440,7 @@ static int queue_io(struct mapped_device *md, struct bio *bio) { down_write(&md->io_lock); - if (!test_bit(DMF_BLOCK_IO, &md->flags)) { + if (!test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) { up_write(&md->io_lock); return 1; } @@ -950,10 +951,10 @@ static int dm_request(struct request_queue *q, struct bio *bio) part_stat_unlock(); /* - * If we're suspended we have to queue - * this io for later. + * If we're suspended or the thread is processing barriers + * we have to queue this io for later. */ - while (test_bit(DMF_BLOCK_IO, &md->flags)) { + while (test_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags)) { up_read(&md->io_lock); if (bio_rw(bio) != READA) @@ -997,7 +998,7 @@ static int dm_any_congested(void *congested_data, int bdi_bits) struct mapped_device *md = congested_data; struct dm_table *map; - if (!test_bit(DMF_BLOCK_IO, &md->flags)) { + if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { map = dm_get_table(md); if (map) { r = dm_table_any_congested(map, bdi_bits); @@ -1443,7 +1444,8 @@ static void dm_wq_work(struct work_struct *work) spin_unlock_irq(&md->deferred_lock); if (!c) { - clear_bit(DMF_BLOCK_IO, &md->flags); + clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); + clear_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); break; } @@ -1574,10 +1576,12 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags) } /* - * First we set the BLOCK_IO flag so no more ios will be mapped. + * First we set the DMF_QUEUE_IO_TO_THREAD flag so no more ios + * will be mapped. */ down_write(&md->io_lock); - set_bit(DMF_BLOCK_IO, &md->flags); + set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); + set_bit(DMF_QUEUE_IO_TO_THREAD, &md->flags); up_write(&md->io_lock); -- 2.30.2