block: add internal hd part table references
We can't use krefs since it's apparently restricted to very basic
reference counting.
This reverts commit e4a683c8.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 500c080..2f4002f 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -70,7 +70,7 @@
part_stat_inc(cpu, part, merges[rw]);
} else {
part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
- if (!kref_test_and_get(&part->ref)) {
+ if (!hd_struct_try_get(part)) {
/*
* The partition is already being removed,
* the request will be accounted on the disk only
@@ -80,7 +80,7 @@
* it as any other partition.
*/
part = &rq->rq_disk->part0;
- kref_get(&part->ref);
+ hd_struct_get(part);
}
part_round_stats(cpu, part);
part_inc_in_flight(part, rw);
@@ -1818,7 +1818,7 @@
part_round_stats(cpu, part);
part_dec_in_flight(part, rw);
- kref_put(&part->ref, __delete_partition);
+ hd_struct_put(part);
part_stat_unlock();
}
}
diff --git a/block/blk-merge.c b/block/blk-merge.c
index b06b83b..00b7d31 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -356,7 +356,7 @@
part_round_stats(cpu, part);
part_dec_in_flight(part, rq_data_dir(req));
- kref_put(&part->ref, __delete_partition);
+ hd_struct_put(part);
part_stat_unlock();
}
}
diff --git a/block/genhd.c b/block/genhd.c
index 85c1505..399d37e 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1192,7 +1192,8 @@
return NULL;
}
disk->part_tbl->part[0] = &disk->part0;
- kref_init(&disk->part0.ref);
+
+ hd_ref_init(&disk->part0);
disk->minors = minors;
rand_initialize_disk(disk);
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 48209f5..011520d 100644
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -381,10 +381,8 @@
put_device(part_to_dev(part));
}
-void __delete_partition(struct kref *ref)
+void __delete_partition(struct hd_struct *part)
{
- struct hd_struct *part = container_of(ref, struct hd_struct, ref);
-
call_rcu(&part->rcu_head, delete_partition_rcu_cb);
}
@@ -406,7 +404,7 @@
kobject_put(part->holder_dir);
device_del(part_to_dev(part));
- kref_put(&part->ref, __delete_partition);
+ hd_struct_put(part);
}
static ssize_t whole_disk_show(struct device *dev,
@@ -505,7 +503,7 @@
if (!dev_get_uevent_suppress(ddev))
kobject_uevent(&pdev->kobj, KOBJ_ADD);
- kref_init(&p->ref);
+ hd_ref_init(p);
return p;
out_free_info:
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 2ba2792..2d04681 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -115,8 +115,8 @@
#else
struct disk_stats dkstats;
#endif
+ atomic_t ref;
struct rcu_head rcu_head;
- struct kref ref;
};
#define GENHD_FL_REMOVABLE 1
@@ -584,7 +584,7 @@
sector_t len, int flags,
struct partition_meta_info
*info);
-extern void __delete_partition(struct kref *ref);
+extern void __delete_partition(struct hd_struct *);
extern void delete_partition(struct gendisk *, int);
extern void printk_all_partitions(void);
@@ -613,6 +613,29 @@
const char *buf, size_t count);
#endif /* CONFIG_FAIL_MAKE_REQUEST */
+static inline void hd_ref_init(struct hd_struct *part)
+{
+ atomic_set(&part->ref, 1);
+ smp_mb();
+}
+
+static inline void hd_struct_get(struct hd_struct *part)
+{
+ atomic_inc(&part->ref);
+ smp_mb__after_atomic_inc();
+}
+
+static inline int hd_struct_try_get(struct hd_struct *part)
+{
+ return atomic_inc_not_zero(&part->ref);
+}
+
+static inline void hd_struct_put(struct hd_struct *part)
+{
+ if (atomic_dec_and_test(&part->ref))
+ __delete_partition(part);
+}
+
#else /* CONFIG_BLOCK */
static inline void printk_all_partitions(void) { }
diff --git a/include/linux/kref.h b/include/linux/kref.h
index 90b9e44..6cc38fc 100644
--- a/include/linux/kref.h
+++ b/include/linux/kref.h
@@ -23,7 +23,6 @@
void kref_init(struct kref *kref);
void kref_get(struct kref *kref);
-int kref_test_and_get(struct kref *kref);
int kref_put(struct kref *kref, void (*release) (struct kref *kref));
#endif /* _KREF_H_ */
diff --git a/lib/kref.c b/lib/kref.c
index e7a6e10..d3d227a 100644
--- a/lib/kref.c
+++ b/lib/kref.c
@@ -37,18 +37,6 @@
}
/**
- * kref_test_and_get - increment refcount for object only if refcount is not
- * zero.
- * @kref: object.
- *
- * Return non-zero if the refcount was incremented, 0 otherwise
- */
-int kref_test_and_get(struct kref *kref)
-{
- return atomic_inc_not_zero(&kref->refcount);
-}
-
-/**
* kref_put - decrement refcount for object.
* @kref: object.
* @release: pointer to the function that will clean up the object when the