dm: rearrange core declarations for extended use from dm-zone.c

Move the definitions of struct dm_target_io, struct dm_io and the bits
of the flags field of struct mapped_device from dm.c to dm-core.h to
make them usable from dm-zone.c. For the same reason, declare
dec_pending() in dm-core.h after renaming it to dm_io_dec_pending().
And for symmetry of the function names, introduce the inline helper
dm_io_inc_pending() instead of directly using atomic_inc() calls.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Author: damien-lemoal

drivers/md/dm-core.h

@@ -116,6 +116,19 @@ struct mapped_device {
 	struct srcu_struct io_barrier;
 };
 
+/*
+ * Bits for the flags field of struct mapped_device.
+ */
+#define DMF_BLOCK_IO_FOR_SUSPEND 0
+#define DMF_SUSPENDED 1
+#define DMF_FROZEN 2
+#define DMF_FREEING 3
+#define DMF_DELETING 4
+#define DMF_NOFLUSH_SUSPENDING 5
+#define DMF_DEFERRED_REMOVE 6
+#define DMF_SUSPENDED_INTERNALLY 7
+#define DMF_POST_SUSPENDING 8
+
 void disable_discard(struct mapped_device *md);
 void disable_write_same(struct mapped_device *md);
 void disable_write_zeroes(struct mapped_device *md);
@@ -173,6 +186,45 @@ struct dm_table {
 #endif
 };
 
+/*
+ * One of these is allocated per clone bio.
+ */
+#define DM_TIO_MAGIC 7282014
+struct dm_target_io {
+	unsigned int magic;
+	struct dm_io *io;
+	struct dm_target *ti;
+	unsigned int target_bio_nr;
+	unsigned int *len_ptr;
+	bool inside_dm_io;
+	struct bio clone;
+};
+
+/*
+ * One of these is allocated per original bio.
+ * It contains the first clone used for that original.
+ */
+#define DM_IO_MAGIC 5191977
+struct dm_io {
+	unsigned int magic;
+	struct mapped_device *md;
+	blk_status_t status;
+	atomic_t io_count;
+	struct bio *orig_bio;
+	unsigned long start_time;
+	spinlock_t endio_lock;
+	struct dm_stats_aux stats_aux;
+	/* last member of dm_target_io is 'struct bio' */
+	struct dm_target_io tio;
+};
+
+static inline void dm_io_inc_pending(struct dm_io *io)
+{
+	atomic_inc(&io->io_count);
+}
+
+void dm_io_dec_pending(struct dm_io *io, blk_status_t error);
+
 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
 {
 	return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;

drivers/md/dm.c

@@ -74,38 +74,6 @@ struct clone_info {
 	unsigned sector_count;
 };
 
-/*
- * One of these is allocated per clone bio.
- */
-#define DM_TIO_MAGIC 7282014
-struct dm_target_io {
-	unsigned magic;
-	struct dm_io *io;
-	struct dm_target *ti;
-	unsigned target_bio_nr;
-	unsigned *len_ptr;
-	bool inside_dm_io;
-	struct bio clone;
-};
-
-/*
- * One of these is allocated per original bio.
- * It contains the first clone used for that original.
- */
-#define DM_IO_MAGIC 5191977
-struct dm_io {
-	unsigned magic;
-	struct mapped_device *md;
-	blk_status_t status;
-	atomic_t io_count;
-	struct bio *orig_bio;
-	unsigned long start_time;
-	spinlock_t endio_lock;
-	struct dm_stats_aux stats_aux;
-	/* last member of dm_target_io is 'struct bio' */
-	struct dm_target_io tio;
-};
-
 #define DM_TARGET_IO_BIO_OFFSET (offsetof(struct dm_target_io, clone))
 #define DM_IO_BIO_OFFSET \
 	(offsetof(struct dm_target_io, clone) + offsetof(struct dm_io, tio))
@@ -137,19 +105,6 @@ EXPORT_SYMBOL_GPL(dm_bio_get_target_bio_nr);
 
 #define MINOR_ALLOCED ((void *)-1)
 
-/*
- * Bits for the md->flags field.
- */
-#define DMF_BLOCK_IO_FOR_SUSPEND 0
-#define DMF_SUSPENDED 1
-#define DMF_FROZEN 2
-#define DMF_FREEING 3
-#define DMF_DELETING 4
-#define DMF_NOFLUSH_SUSPENDING 5
-#define DMF_DEFERRED_REMOVE 6
-#define DMF_SUSPENDED_INTERNALLY 7
-#define DMF_POST_SUSPENDING 8
-
 #define DM_NUMA_NODE NUMA_NO_NODE
 static int dm_numa_node = DM_NUMA_NODE;
 
@@ -825,7 +780,7 @@ static int __noflush_suspending(struct mapped_device *md)
  * Decrements the number of outstanding ios that a bio has been
  * cloned into, completing the original io if necc.
  */
-static void dec_pending(struct dm_io *io, blk_status_t error)
+void dm_io_dec_pending(struct dm_io *io, blk_status_t error)
 {
 	unsigned long flags;
 	blk_status_t io_error;
@@ -979,7 +934,7 @@ static void clone_endio(struct bio *bio)
 	}
 
 	free_tio(tio);
-	dec_pending(io, error);
+	dm_io_dec_pending(io, error);
 }
 
 /*
@@ -1247,7 +1202,7 @@ static blk_qc_t __map_bio(struct dm_target_io *tio)
 	 * anything, the target has assumed ownership of
 	 * this io.
 	 */
-	atomic_inc(&io->io_count);
+	dm_io_inc_pending(io);
 	sector = clone->bi_iter.bi_sector;
 
 	if (unlikely(swap_bios_limit(ti, clone))) {
@@ -1273,15 +1228,15 @@ static blk_qc_t __map_bio(struct dm_target_io *tio)
 			up(&md->swap_bios_semaphore);
 		}
 		free_tio(tio);
-		dec_pending(io, BLK_STS_IOERR);
+		dm_io_dec_pending(io, BLK_STS_IOERR);
 		break;
 	case DM_MAPIO_REQUEUE:
 		if (unlikely(swap_bios_limit(ti, clone))) {
 			struct mapped_device *md = io->md;
 			up(&md->swap_bios_semaphore);
 		}
 		free_tio(tio);
-		dec_pending(io, BLK_STS_DM_REQUEUE);
+		dm_io_dec_pending(io, BLK_STS_DM_REQUEUE);
 		break;
 	default:
 		DMWARN("unimplemented target map return value: %d", r);
@@ -1570,7 +1525,7 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
 
 	if (bio->bi_opf & REQ_PREFLUSH) {
 		error = __send_empty_flush(&ci);
-		/* dec_pending submits any data associated with flush */
+		/* dm_io_dec_pending submits any data associated with flush */
 	} else if (op_is_zone_mgmt(bio_op(bio))) {
 		ci.bio = bio;
 		ci.sector_count = 0;
@@ -1611,7 +1566,7 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
 	}
 
 	/* drop the extra reference count */
-	dec_pending(ci.io, errno_to_blk_status(error));
+	dm_io_dec_pending(ci.io, errno_to_blk_status(error));
 	return ret;
 }