[PATCH] dm table: store md
Store an up-pointer to the owning struct mapped_device in every table when it
is created.
Access it with:
struct mapped_device *dm_table_get_md(struct dm_table *t)
Tables linked to md must be destroyed before the md itself.
Signed-off-by: Mike Anderson <andmike@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 0693b6f..65826bd 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -244,9 +244,9 @@
dm_table_put(table);
}
- dm_put(hc->md);
if (hc->new_map)
dm_table_put(hc->new_map);
+ dm_put(hc->md);
free_cell(hc);
}
@@ -985,33 +985,43 @@
int r;
struct hash_cell *hc;
struct dm_table *t;
+ struct mapped_device *md;
- r = dm_table_create(&t, get_mode(param), param->target_count);
+ md = find_device(param);
+ if (!md)
+ return -ENXIO;
+
+ r = dm_table_create(&t, get_mode(param), param->target_count, md);
if (r)
- return r;
+ goto out;
r = populate_table(t, param, param_size);
if (r) {
dm_table_put(t);
- return r;
+ goto out;
}
down_write(&_hash_lock);
- hc = __find_device_hash_cell(param);
- if (!hc) {
- DMWARN("device doesn't appear to be in the dev hash table.");
- up_write(&_hash_lock);
+ hc = dm_get_mdptr(md);
+ if (!hc || hc->md != md) {
+ DMWARN("device has been removed from the dev hash table.");
dm_table_put(t);
- return -ENXIO;
+ up_write(&_hash_lock);
+ r = -ENXIO;
+ goto out;
}
if (hc->new_map)
dm_table_put(hc->new_map);
hc->new_map = t;
- param->flags |= DM_INACTIVE_PRESENT_FLAG;
-
- r = __dev_status(hc->md, param);
up_write(&_hash_lock);
+
+ param->flags |= DM_INACTIVE_PRESENT_FLAG;
+ r = __dev_status(md, param);
+
+out:
+ dm_put(md);
+
return r;
}
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 9558a4a..84f4594 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -22,6 +22,7 @@
#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1)
struct dm_table {
+ struct mapped_device *md;
atomic_t holders;
/* btree table */
@@ -206,7 +207,8 @@
return 0;
}
-int dm_table_create(struct dm_table **result, int mode, unsigned num_targets)
+int dm_table_create(struct dm_table **result, int mode,
+ unsigned num_targets, struct mapped_device *md)
{
struct dm_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
@@ -229,6 +231,7 @@
}
t->mode = mode;
+ t->md = md;
*result = t;
return 0;
}
@@ -952,12 +955,20 @@
return ret;
}
+struct mapped_device *dm_table_get_md(struct dm_table *t)
+{
+ dm_get(t->md);
+
+ return t->md;
+}
+
EXPORT_SYMBOL(dm_vcalloc);
EXPORT_SYMBOL(dm_get_device);
EXPORT_SYMBOL(dm_put_device);
EXPORT_SYMBOL(dm_table_event);
EXPORT_SYMBOL(dm_table_get_size);
EXPORT_SYMBOL(dm_table_get_mode);
+EXPORT_SYMBOL(dm_table_get_md);
EXPORT_SYMBOL(dm_table_put);
EXPORT_SYMBOL(dm_table_get);
EXPORT_SYMBOL(dm_table_unplug_all);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 3d121cb..b99df48 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1007,18 +1007,18 @@
void dm_put(struct mapped_device *md)
{
- struct dm_table *map = dm_get_table(md);
+ struct dm_table *map;
if (atomic_dec_and_test(&md->holders)) {
+ map = dm_get_table(md);
if (!dm_suspended(md)) {
dm_table_presuspend_targets(map);
dm_table_postsuspend_targets(map);
}
__unbind(md);
+ dm_table_put(map);
free_dev(md);
}
-
- dm_table_put(map);
}
/*
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 17ffa8d..79e8000 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -89,7 +89,8 @@
* Functions for manipulating a table. Tables are also reference
* counted.
*---------------------------------------------------------------*/
-int dm_table_create(struct dm_table **result, int mode, unsigned num_targets);
+int dm_table_create(struct dm_table **result, int mode,
+ unsigned num_targets, struct mapped_device *md);
void dm_table_get(struct dm_table *t);
void dm_table_put(struct dm_table *t);
@@ -107,6 +108,7 @@
unsigned int dm_table_get_num_targets(struct dm_table *t);
struct list_head *dm_table_get_devices(struct dm_table *t);
int dm_table_get_mode(struct dm_table *t);
+struct mapped_device *dm_table_get_md(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_resume_targets(struct dm_table *t);