dm: remove fmode_t argument from .prepare_ioctl hook

Use the fmode_t that is passed to dm_blk_ioctl() rather than
inconsistently (varies across targets) drop it on the floor by
overriding it with the fmode_t stored in 'struct dm_dev'.

All the persistent reservation functions weren't using the fmode_t they
got back from .prepare_ioctl so remove them.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-flakey.c

@@ -442,8 +442,7 @@ static void flakey_status(struct dm_target *ti, status_type_t type,
 	}
 }
 
-static int flakey_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+static int flakey_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct flakey_c *fc = ti->private;
 

drivers/md/dm-linear.c

@@ -130,8 +130,7 @@ static void linear_status(struct dm_target *ti, status_type_t type,
 	}
 }
 
-static int linear_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+static int linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct linear_c *lc = (struct linear_c *) ti->private;
 	struct dm_dev *dev = lc->dev;

drivers/md/dm-log-writes.c

@@ -864,7 +864,7 @@ static void log_writes_status(struct dm_target *ti, status_type_t type,
 }
 
 static int log_writes_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+				    struct block_device **bdev)
 {
 	struct log_writes_c *lc = ti->private;
 	struct dm_dev *dev = lc->dev;

drivers/md/dm-mpath.c

@@ -1876,7 +1876,7 @@ out:
 }
 
 static int multipath_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+				   struct block_device **bdev)
 {
 	struct multipath *m = ti->private;
 	struct pgpath *current_pgpath;
@@ -1889,7 +1889,6 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
 	if (current_pgpath) {
 		if (!test_bit(MPATHF_QUEUE_IO, &m->flags)) {
 			*bdev = current_pgpath->path.dev->bdev;
-			*mode = current_pgpath->path.dev->mode;
 			r = 0;
 		} else {
 			/* pg_init has not started or completed */

drivers/md/dm-switch.c

@@ -512,8 +512,7 @@ static void switch_status(struct dm_target *ti, status_type_t type,
  *
  * Passthrough all ioctls to the path for sector 0
  */
-static int switch_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+static int switch_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct switch_ctx *sctx = ti->private;
 	unsigned path_nr;
@@ -521,7 +520,6 @@ static int switch_prepare_ioctl(struct dm_target *ti,
 	path_nr = switch_get_path_nr(sctx, 0);
 
 	*bdev = sctx->path_list[path_nr].dmdev->bdev;
-	*mode = sctx->path_list[path_nr].dmdev->mode;
 
 	/*
 	 * Only pass ioctls through if the device sizes match exactly.

drivers/md/dm-verity-target.c

@@ -723,8 +723,7 @@ static void verity_status(struct dm_target *ti, status_type_t type,
 	}
 }
 
-static int verity_prepare_ioctl(struct dm_target *ti,
-		struct block_device **bdev, fmode_t *mode)
+static int verity_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct dm_verity *v = ti->private;
 

drivers/md/dm-zoned-target.c

@@ -898,8 +898,7 @@ static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
 /*
  * Pass on ioctl to the backend device.
  */
-static int dmz_prepare_ioctl(struct dm_target *ti,
-			     struct block_device **bdev, fmode_t *mode)
+static int dmz_prepare_ioctl(struct dm_target *ti, struct block_device **bdev)
 {
 	struct dmz_target *dmz = ti->private;
 

drivers/md/dm.c

@@ -459,7 +459,7 @@ static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 }
 
 static int dm_prepare_ioctl(struct mapped_device *md, int *srcu_idx,
-			    struct block_device **bdev, fmode_t *mode)
+			    struct block_device **bdev)
 	__acquires(md->io_barrier)
 {
 	struct dm_target *tgt;
@@ -483,7 +483,7 @@ retry:
 	if (dm_suspended_md(md))
 		return -EAGAIN;
 
-	r = tgt->type->prepare_ioctl(tgt, bdev, mode);
+	r = tgt->type->prepare_ioctl(tgt, bdev);
 	if (r == -ENOTCONN && !fatal_signal_pending(current)) {
 		dm_put_live_table(md, *srcu_idx);
 		msleep(10);
@@ -505,7 +505,7 @@ static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode,
 	struct mapped_device *md = bdev->bd_disk->private_data;
 	int r, srcu_idx;
 
-	r = dm_prepare_ioctl(md, &srcu_idx, &bdev, &mode);
+	r = dm_prepare_ioctl(md, &srcu_idx, &bdev);
 	if (r < 0)
 		goto out;
 
@@ -3034,10 +3034,9 @@ static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
 {
 	struct mapped_device *md = bdev->bd_disk->private_data;
 	const struct pr_ops *ops;
-	fmode_t mode;
 	int r, srcu_idx;
 
-	r = dm_prepare_ioctl(md, &srcu_idx, &bdev, &mode);
+	r = dm_prepare_ioctl(md, &srcu_idx, &bdev);
 	if (r < 0)
 		goto out;
 
@@ -3055,10 +3054,9 @@ static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
 {
 	struct mapped_device *md = bdev->bd_disk->private_data;
 	const struct pr_ops *ops;
-	fmode_t mode;
 	int r, srcu_idx;
 
-	r = dm_prepare_ioctl(md, &srcu_idx, &bdev, &mode);
+	r = dm_prepare_ioctl(md, &srcu_idx, &bdev);
 	if (r < 0)
 		goto out;
 
@@ -3077,10 +3075,9 @@ static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
 {
 	struct mapped_device *md = bdev->bd_disk->private_data;
 	const struct pr_ops *ops;
-	fmode_t mode;
 	int r, srcu_idx;
 
-	r = dm_prepare_ioctl(md, &srcu_idx, &bdev, &mode);
+	r = dm_prepare_ioctl(md, &srcu_idx, &bdev);
 	if (r < 0)
 		goto out;
 
@@ -3098,10 +3095,9 @@ static int dm_pr_clear(struct block_device *bdev, u64 key)
 {
 	struct mapped_device *md = bdev->bd_disk->private_data;
 	const struct pr_ops *ops;
-	fmode_t mode;
 	int r, srcu_idx;
 
-	r = dm_prepare_ioctl(md, &srcu_idx, &bdev, &mode);
+	r = dm_prepare_ioctl(md, &srcu_idx, &bdev);
 	if (r < 0)
 		goto out;
 

include/linux/device-mapper.h

@@ -90,8 +90,7 @@ typedef void (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
 typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv,
 			      char *result, unsigned maxlen);
 
-typedef int (*dm_prepare_ioctl_fn) (struct dm_target *ti,
-			    struct block_device **bdev, fmode_t *mode);
+typedef int (*dm_prepare_ioctl_fn) (struct dm_target *ti, struct block_device **bdev);
 
 /*
  * These iteration functions are typically used to check (and combine)