From: Yu Kuai <yukuai3@xxxxxxxxxx>
Now that all implementations are internal, it's sensible to build it as
kernel module now.
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/Kconfig | 18 ++++++++
drivers/md/Makefile | 4 +-
drivers/md/md-bitmap.c | 28 +++++++++++-
drivers/md/md-bitmap.h | 7 ++-
drivers/md/md.c | 96 +++++++++++++++++++++++++++++++++++++-----
drivers/md/md.h | 1 -
6 files changed, 137 insertions(+), 17 deletions(-)
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 1e9db8e4acdf..be22ece66919 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -37,6 +37,21 @@ config BLK_DEV_MD
If unsure, say N.
+config MD_BITMAP
+ tristate "MD RAID bitmap support"
+ default y
+ depends on BLK_DEV_MD
+ help
+ If you say Y or M here, support for the write intent bitmap will be
+ enabled. The bitmap can be used to optimize resync speed after power
+ failure or readding a disk, limiting it to recorded dirty sectors in
+ bitmap.
+
+ This feature can be added to existing MD array or MD array can be
+ created with bitmap via mdadm(8).
+
+ If unsure, say Y.
+
config MD_AUTODETECT
bool "Autodetect RAID arrays during kernel boot"
depends on BLK_DEV_MD=y
@@ -54,6 +69,7 @@ config MD_AUTODETECT
config MD_BITMAP_FILE
bool "MD bitmap file support (deprecated)"
default y
+ depends on MD_BITMAP
help
If you say Y here, support for write intent bitmaps in files on an
external file system is enabled. This is an alternative to the internal
@@ -161,6 +177,7 @@ config MD_RAID456
config MD_CLUSTER
tristate "Cluster Support for MD"
+ select MD_BITMAP
depends on BLK_DEV_MD
depends on DLM
default n
@@ -379,6 +396,7 @@ config DM_RAID
select MD_RAID1
select MD_RAID10
select MD_RAID456
+ select MD_BITMAP
select BLK_DEV_MD
help
A dm target that supports RAID1, RAID10, RAID4, RAID5 and RAID6 mappings
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 476a214e4bdc..387670f766b7 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -27,14 +27,14 @@ dm-clone-y += dm-clone-target.o dm-clone-metadata.o
dm-verity-y += dm-verity-target.o
dm-zoned-y += dm-zoned-target.o dm-zoned-metadata.o dm-zoned-reclaim.o
-md-mod-y += md.o md-bitmap.o
+md-mod-y += md.o
raid456-y += raid5.o raid5-cache.o raid5-ppl.o
# Note: link order is important. All raid personalities
# and must come before md.o, as they each initialise
# themselves, and md.o may use the personalities when it
# auto-initialised.
-
+obj-$(CONFIG_MD_BITMAP) += md-bitmap.o
obj-$(CONFIG_MD_RAID0) += raid0.o
obj-$(CONFIG_MD_RAID1) += raid1.o
obj-$(CONFIG_MD_RAID10) += raid10.o
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 72cbbe0d3408..097339315517 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -212,6 +212,8 @@ struct bitmap {
int cluster_slot;
};
+static struct workqueue_struct *md_bitmap_wq;
+
static int __bitmap_resize(struct bitmap *bitmap, sector_t blocks,
int chunksize, bool init);
@@ -2960,6 +2962,9 @@ static struct attribute_group md_bitmap_group = {
};
static struct bitmap_operations bitmap_ops = {
+ .version = 1,
+ .owner = THIS_MODULE,
+
.enabled = bitmap_enabled,
.create = bitmap_create,
.resize = bitmap_resize,
@@ -2994,7 +2999,26 @@ static struct bitmap_operations bitmap_ops = {
.group = &md_bitmap_group,
};
-void mddev_set_bitmap_ops(struct mddev *mddev)
+static int __init bitmap_init(void)
+{
+ md_bitmap_wq = alloc_workqueue("md_bitmap", WQ_MEM_RECLAIM | WQ_UNBOUND,
+ 0);
+ if (!md_bitmap_wq)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&bitmap_ops.list);
+ register_md_bitmap(&bitmap_ops);
+ return 0;
+}
+
+static void __exit bitmap_exit(void)
{
- mddev->bitmap_ops = &bitmap_ops;
+ destroy_workqueue(md_bitmap_wq);
+ unregister_md_bitmap(&bitmap_ops);
}
+
+module_init(bitmap_init);
+module_exit(bitmap_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Bitmap for MD");
diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h
index fefa00bc438e..afd28d06aae9 100644
--- a/drivers/md/md-bitmap.h
+++ b/drivers/md/md-bitmap.h
@@ -71,6 +71,10 @@ struct md_bitmap_stats {
};
struct bitmap_operations {
+ int version;
+ struct module *owner;
+ struct list_head list;
+
bool (*enabled)(void *data);
int (*create)(struct mddev *mddev, int slot);
int (*resize)(struct mddev *mddev, sector_t blocks, int chunksize);
@@ -114,7 +118,8 @@ struct bitmap_operations {
};
/* the bitmap API */
-void mddev_set_bitmap_ops(struct mddev *mddev);
+void register_md_bitmap(struct bitmap_operations *op);
+void unregister_md_bitmap(struct bitmap_operations *op);
static inline bool md_bitmap_registered(struct mddev *mddev)
{
diff --git a/drivers/md/md.c b/drivers/md/md.c
index f1f70803439d..b1c9c0d4d5e7 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -83,6 +83,9 @@ static const char *action_name[NR_SYNC_ACTIONS] = {
static LIST_HEAD(pers_list);
static DEFINE_SPINLOCK(pers_lock);
+static LIST_HEAD(bitmap_list);
+static DEFINE_SPINLOCK(bitmap_lock);
+
static const struct kobj_type md_ktype;
const struct md_cluster_operations *md_cluster_ops;
@@ -100,7 +103,6 @@ static struct workqueue_struct *md_wq;
* workqueue whith reconfig_mutex grabbed.
*/
static struct workqueue_struct *md_misc_wq;
-struct workqueue_struct *md_bitmap_wq;
static int remove_and_add_spares(struct mddev *mddev,
struct md_rdev *this);
@@ -652,15 +654,95 @@ static void active_io_release(struct percpu_ref *ref)
static void no_op(struct percpu_ref *r) {}
+void register_md_bitmap(struct bitmap_operations *op)
+{
+ pr_info("md: bitmap version %d registered\n", op->version);
+
+ spin_lock(&bitmap_lock);
+ list_add_tail(&op->list, &bitmap_list);
+ spin_unlock(&bitmap_lock);
+}
+EXPORT_SYMBOL_GPL(register_md_bitmap);
+
+void unregister_md_bitmap(struct bitmap_operations *op)
+{
+ pr_info("md: bitmap version %d unregistered\n", op->version);
+
+ spin_lock(&bitmap_lock);
+ list_del_init(&op->list);
+ spin_unlock(&bitmap_lock);
+}
+EXPORT_SYMBOL_GPL(unregister_md_bitmap);
+
+static struct bitmap_operations *__find_bitmap(int version)
+{
+ struct bitmap_operations *op;
+
+ list_for_each_entry(op, &bitmap_list, list)
+ if (op->version == version) {
+ if (try_module_get(op->owner))
+ return op;
+ else
+ return NULL;
+ }
+
+ return NULL;
+}
+
+static struct bitmap_operations *find_bitmap(int version)
+{
+ struct bitmap_operations *op = NULL;
+
+ spin_lock(&bitmap_lock);
+ op = __find_bitmap(version);
+ spin_unlock(&bitmap_lock);
+
+ if (op)
+ return op;
+
+ if (request_module("md-bitmap") != 0)
+ return NULL;
+
+ spin_lock(&bitmap_lock);
+ op = __find_bitmap(version);
+ spin_unlock(&bitmap_lock);
+
+ return op;
+}
+
+static void mddev_set_bitmap_ops(struct mddev *mddev, int version)
+{
+ struct bitmap_operations *op = find_bitmap(version);
+
+ if (!op)
+ pr_warn_once("md: can't find version %d bitmap\n", version);
+
+ mddev->bitmap_ops = op;
+}
+
+static void mddev_clear_bitmap_ops(struct mddev *mddev)
+{
+ if (!mddev->bitmap_ops)
+ return;
+
+ module_put(mddev->bitmap_ops->owner);
+ mddev->bitmap_ops = NULL;
+}
+
int mddev_init(struct mddev *mddev)
{
+ /* TODO: support more versions */
+ mddev_set_bitmap_ops(mddev, 1);
if (percpu_ref_init(&mddev->active_io, active_io_release,
- PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
+ PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
+ mddev_clear_bitmap_ops(mddev);
return -ENOMEM;
+ }
if (percpu_ref_init(&mddev->writes_pending, no_op,
PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
+ mddev_clear_bitmap_ops(mddev);
percpu_ref_exit(&mddev->active_io);
return -ENOMEM;
}
@@ -688,7 +770,6 @@ int mddev_init(struct mddev *mddev)
mddev->resync_min = 0;
mddev->resync_max = MaxSector;
mddev->level = LEVEL_NONE;
- mddev_set_bitmap_ops(mddev);
INIT_WORK(&mddev->sync_work, md_start_sync);
INIT_WORK(&mddev->del_work, mddev_delayed_delete);
@@ -699,6 +780,7 @@ EXPORT_SYMBOL_GPL(mddev_init);
void mddev_destroy(struct mddev *mddev)
{
+ mddev_clear_bitmap_ops(mddev);
percpu_ref_exit(&mddev->active_io);
percpu_ref_exit(&mddev->writes_pending);
}
@@ -9977,11 +10059,6 @@ static int __init md_init(void)
if (!md_misc_wq)
goto err_misc_wq;
- md_bitmap_wq = alloc_workqueue("md_bitmap", WQ_MEM_RECLAIM | WQ_UNBOUND,
- 0);
- if (!md_bitmap_wq)
- goto err_bitmap_wq;
-
ret = __register_blkdev(MD_MAJOR, "md", md_probe);
if (ret < 0)
goto err_md;
@@ -10000,8 +10077,6 @@ static int __init md_init(void)
err_mdp:
unregister_blkdev(MD_MAJOR, "md");
err_md:
- destroy_workqueue(md_bitmap_wq);
-err_bitmap_wq:
destroy_workqueue(md_misc_wq);
err_misc_wq:
destroy_workqueue(md_wq);
@@ -10308,7 +10383,6 @@ static __exit void md_exit(void)
spin_unlock(&all_mddevs_lock);
destroy_workqueue(md_misc_wq);
- destroy_workqueue(md_bitmap_wq);
destroy_workqueue(md_wq);
}
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 7e8276d2dadc..aea9693ff6ef 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -977,7 +977,6 @@ struct mdu_array_info_s;
struct mdu_disk_info_s;
extern int mdp_major;
-extern struct workqueue_struct *md_bitmap_wq;
void md_autostart_arrays(int part);
int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info);
int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info);
--
2.39.2
