This patch introduces a framework to cancel state changes done by
a target specific presuspend function.
Signed-off-by: Takahiro Yasui <tyasui@xxxxxxxxxx>
---
drivers/md/dm-table.c | 36 +++++++++++++++++++++++++++++++-----
drivers/md/dm.c | 8 ++++++--
drivers/md/dm.h | 1 +
include/linux/device-mapper.h | 2 ++
4 files changed, 40 insertions(+), 7 deletions(-)
Index: linux-2.6.33-rc1-dm/drivers/md/dm-table.c
===================================================================
--- linux-2.6.33-rc1-dm.orig/drivers/md/dm-table.c
+++ linux-2.6.33-rc1-dm/drivers/md/dm-table.c
@@ -26,6 +26,13 @@
#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t))
#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
+/* Type of suspend */
+enum suspend_action {
+ PRESUSPEND,
+ POSTSUSPEND,
+ CANCEL_PRESUSPEND,
+};
+
/*
* The table has always exactly one reference from either mapped_device->map
* or hash_cell->new_map. This reference is not counted in table->holders.
@@ -1129,17 +1136,28 @@ fmode_t dm_table_get_mode(struct dm_tabl
return t->mode;
}
-static void suspend_targets(struct dm_table *t, unsigned postsuspend)
+static void suspend_targets(struct dm_table *t, enum suspend_action action)
{
int i = t->num_targets;
struct dm_target *ti = t->targets;
while (i--) {
- if (postsuspend) {
+ switch (action) {
+ case PRESUSPEND:
+ if (ti->type->presuspend)
+ ti->type->presuspend(ti);
+ break;
+
+ case POSTSUSPEND:
if (ti->type->postsuspend)
ti->type->postsuspend(ti);
- } else if (ti->type->presuspend)
- ti->type->presuspend(ti);
+ break;
+
+ case CANCEL_PRESUSPEND:
+ if (ti->type->cancel_presuspend)
+ ti->type->cancel_presuspend(ti);
+ break;
+ }
ti++;
}
@@ -1158,7 +1176,15 @@ void dm_table_postsuspend_targets(struct
if (!t)
return;
- suspend_targets(t, 1);
+ suspend_targets(t, POSTSUSPEND);
+}
+
+void dm_table_cancel_presuspend_targets(struct dm_table *t)
+{
+ if (!t)
+ return;
+
+ suspend_targets(t, CANCEL_PRESUSPEND);
}
int dm_table_resume_targets(struct dm_table *t)
Index: linux-2.6.33-rc1-dm/drivers/md/dm.c
===================================================================
--- linux-2.6.33-rc1-dm.orig/drivers/md/dm.c
+++ linux-2.6.33-rc1-dm/drivers/md/dm.c
@@ -2475,7 +2475,6 @@ int dm_suspend(struct mapped_device *md,
if (noflush)
set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
- /* This does not get reverted if there's an error later. */
dm_table_presuspend_targets(map);
/*
@@ -2486,8 +2485,10 @@ int dm_suspend(struct mapped_device *md,
*/
if (!noflush && do_lockfs) {
r = lock_fs(md);
- if (r)
+ if (r) {
+ dm_table_cancel_presuspend_targets(map);
goto out;
+ }
}
/*
@@ -2541,6 +2542,9 @@ int dm_suspend(struct mapped_device *md,
start_queue(md->queue);
unlock_fs(md);
+
+ dm_table_cancel_presuspend_targets(map);
+
goto out; /* pushback list is already flushed, so skip flush */
}
Index: linux-2.6.33-rc1-dm/drivers/md/dm.h
===================================================================
--- linux-2.6.33-rc1-dm.orig/drivers/md/dm.h
+++ linux-2.6.33-rc1-dm/drivers/md/dm.h
@@ -56,6 +56,7 @@ void dm_table_set_restrictions(struct dm
struct list_head *dm_table_get_devices(struct dm_table *t);
void dm_table_presuspend_targets(struct dm_table *t);
void dm_table_postsuspend_targets(struct dm_table *t);
+void dm_table_cancel_presuspend_targets(struct dm_table *t);
int dm_table_resume_targets(struct dm_table *t);
int dm_table_any_congested(struct dm_table *t, int bdi_bits);
int dm_table_any_busy_target(struct dm_table *t);
Index: linux-2.6.33-rc1-dm/include/linux/device-mapper.h
===================================================================
--- linux-2.6.33-rc1-dm.orig/include/linux/device-mapper.h
+++ linux-2.6.33-rc1-dm/include/linux/device-mapper.h
@@ -69,6 +69,7 @@ typedef void (*dm_flush_fn) (struct dm_t
typedef void (*dm_presuspend_fn) (struct dm_target *ti);
typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
typedef int (*dm_preresume_fn) (struct dm_target *ti);
+typedef void (*dm_cancel_presuspend_fn) (struct dm_target *ti);
typedef void (*dm_resume_fn) (struct dm_target *ti);
typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
@@ -146,6 +147,7 @@ struct target_type {
dm_flush_fn flush;
dm_presuspend_fn presuspend;
dm_postsuspend_fn postsuspend;
+ dm_cancel_presuspend_fn cancel_presuspend;
dm_preresume_fn preresume;
dm_resume_fn resume;
dm_status_fn status;
--
Takahiro Yasui
Hitachi Computer Products (America), Inc.
--
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