[PATCH 5/6] dm: split out a helper to find the ioctl target

From: Christoph Hellwig
Date: Tue Aug 04 2015 - 03:14:40 EST


We want to reuse this code for the persistent reservation handling,
so move it into a helper.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/md/dm.c | 50 ++++++++++++++++++++++++++++++++------------------
1 file changed, 32 insertions(+), 18 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index c68eb91..8dfc760 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -556,18 +556,16 @@ static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
return dm_get_geometry(md, geo);
}

-static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode,
- unsigned int cmd, unsigned long arg)
+static int dm_get_ioctl_table(struct mapped_device *md,
+ struct dm_target **tgt, struct block_device **bdev,
+ fmode_t *mode, int *srcu_idx)
{
- struct mapped_device *md = bdev->bd_disk->private_data;
- int srcu_idx;
struct dm_table *map;
- struct dm_target *tgt;
- int r = -ENOTTY;
+ int r;

retry:
- map = dm_get_live_table(md, &srcu_idx);
-
+ r = -ENOTTY;
+ map = dm_get_live_table(md, srcu_idx);
if (!map || !dm_table_get_size(map))
goto out;

@@ -575,8 +573,9 @@ retry:
if (dm_table_get_num_targets(map) != 1)
goto out;

- tgt = dm_table_get_target(map, 0);
- if (!tgt->type->ioctl)
+ *tgt = dm_table_get_target(map, 0);
+
+ if (!(*tgt)->type->ioctl)
goto out;

if (dm_suspended_md(md)) {
@@ -584,10 +583,32 @@ retry:
goto out;
}

- r = tgt->type->ioctl(tgt, &bdev, &mode);
+ r = (*tgt)->type->ioctl(*tgt, bdev, mode);
if (r < 0)
goto out;

+ return r;
+
+out:
+ dm_put_live_table(md, *srcu_idx);
+ if (r == -ENOTCONN) {
+ msleep(10);
+ goto retry;
+ }
+ return r;
+}
+
+static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode,
+ unsigned int cmd, unsigned long arg)
+{
+ struct mapped_device *md = bdev->bd_disk->private_data;
+ struct dm_target *tgt;
+ int srcu_idx, r;
+
+ r = dm_get_ioctl_table(md, &tgt, &bdev, &mode, &srcu_idx);
+ if (r < 0)
+ return r;
+
if (r > 0) {
r = scsi_verify_blk_ioctl(NULL, cmd);
if (r)
@@ -595,15 +616,8 @@ retry:
}

r = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
-
out:
dm_put_live_table(md, srcu_idx);
-
- if (r == -ENOTCONN) {
- msleep(10);
- goto retry;
- }
-
return r;
}

--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/