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path: root/drivers/mmc/core/block.c
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Diffstat (limited to 'drivers/mmc/core/block.c')
-rw-r--r--drivers/mmc/core/block.c35
1 files changed, 21 insertions, 14 deletions
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 9890a1532cb0..ce8aed562929 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -28,6 +28,7 @@
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/kdev_t.h>
+#include <linux/kref.h>
#include <linux/blkdev.h>
#include <linux/cdev.h>
#include <linux/mutex.h>
@@ -111,7 +112,7 @@ struct mmc_blk_data {
#define MMC_BLK_CMD23 (1 << 0) /* Can do SET_BLOCK_COUNT for multiblock */
#define MMC_BLK_REL_WR (1 << 1) /* MMC Reliable write support */
- unsigned int usage;
+ struct kref kref;
unsigned int read_only;
unsigned int part_type;
unsigned int reset_done;
@@ -181,10 +182,8 @@ static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
mutex_lock(&open_lock);
md = disk->private_data;
- if (md && md->usage == 0)
+ if (md && !kref_get_unless_zero(&md->kref))
md = NULL;
- if (md)
- md->usage++;
mutex_unlock(&open_lock);
return md;
@@ -196,18 +195,25 @@ static inline int mmc_get_devidx(struct gendisk *disk)
return devidx;
}
-static void mmc_blk_put(struct mmc_blk_data *md)
+static void mmc_blk_kref_release(struct kref *ref)
{
- mutex_lock(&open_lock);
- md->usage--;
- if (md->usage == 0) {
- int devidx = mmc_get_devidx(md->disk);
+ struct mmc_blk_data *md = container_of(ref, struct mmc_blk_data, kref);
+ int devidx;
- ida_simple_remove(&mmc_blk_ida, devidx);
- put_disk(md->disk);
- kfree(md);
- }
+ devidx = mmc_get_devidx(md->disk);
+ ida_simple_remove(&mmc_blk_ida, devidx);
+
+ mutex_lock(&open_lock);
+ md->disk->private_data = NULL;
mutex_unlock(&open_lock);
+
+ put_disk(md->disk);
+ kfree(md);
+}
+
+static void mmc_blk_put(struct mmc_blk_data *md)
+{
+ kref_put(&md->kref, mmc_blk_kref_release);
}
static ssize_t power_ro_lock_show(struct device *dev,
@@ -2327,7 +2333,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
INIT_LIST_HEAD(&md->part);
INIT_LIST_HEAD(&md->rpmbs);
- md->usage = 1;
+ kref_init(&md->kref);
+
md->queue.blkdata = md;
md->disk->major = MMC_BLOCK_MAJOR;