From ca3a931fd33b841cbcc5932f8eac7c43e0909242 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Tue, 3 Oct 2006 01:15:30 -0700 Subject: [PATCH] dm snapshot: add workqueue Add a workqueue so that I/O can be queued up to be flushed from a separate thread (e.g. if local interrupts are disabled). A new per-snapshot spinlock pe_lock is introduced to protect queued_bios. Signed-off-by: Alasdair G Kergon Signed-off-by: Mark McLoughlin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm-snap.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/md/dm-snap.h') diff --git a/drivers/md/dm-snap.h b/drivers/md/dm-snap.h index 221eb8880c80..15fa2ae6cdc2 100644 --- a/drivers/md/dm-snap.h +++ b/drivers/md/dm-snap.h @@ -10,7 +10,9 @@ #define DM_SNAPSHOT_H #include "dm.h" +#include "dm-bio-list.h" #include +#include struct exception_table { uint32_t hash_mask; @@ -112,10 +114,20 @@ struct dm_snapshot { struct exception_table pending; struct exception_table complete; + /* + * pe_lock protects all pending_exception operations and access + * as well as the snapshot_bios list. + */ + spinlock_t pe_lock; + /* The on disk metadata handler */ struct exception_store store; struct kcopyd_client *kcopyd_client; + + /* Queue of snapshot writes for ksnapd to flush */ + struct bio_list queued_bios; + struct work_struct queued_bios_work; }; /* -- cgit v1.2.3