[PATCH 1/6] block: introduce IOCTL for zone mgmt

["Javier González" <javier@javigon.com>]

From: Javier González <javier.gonz@samsung.com>

The current IOCTL interface for zone management is limited by struct
blk_zone_range, which is unfortunately not extensible. Specially, the
lack of flags is problematic for ZNS zoned devices.

This new IOCTL is designed to be a superset of the current one, with
support for flags and bits for extensibility.

Signed-off-by: Javier González <javier.gonz@samsung.com>
Signed-off-by: SelvaKumar S <selvakuma.s1@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Nitesh Shetty <nj.shetty@samsung.com>
---
 block/blk-zoned.c             | 56 ++++++++++++++++++++++++++++++++++-
 block/ioctl.c                 |  2 ++
 include/linux/blkdev.h        |  9 ++++++
 include/uapi/linux/blkzoned.h | 33 +++++++++++++++++++++
 4 files changed, 99 insertions(+), 1 deletion(-)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 81152a260354..e87c60004dc5 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -322,7 +322,7 @@ int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
  * BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE and BLKFINISHZONE ioctl processing.
  * Called from blkdev_ioctl.
  */
-int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
+int blkdev_zone_ops_ioctl(struct block_device *bdev, fmode_t mode,
 			   unsigned int cmd, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
@@ -370,6 +370,60 @@ int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
 				GFP_KERNEL);
 }
 
+/*
+ * Zone management ioctl processing. Extension of blkdev_zone_ops_ioctl(), with
+ * blk_zone_mgmt structure.
+ *
+ * Called from blkdev_ioctl.
+ */
+int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
+			   unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct request_queue *q;
+	struct blk_zone_mgmt zmgmt;
+	enum req_opf op;
+
+	if (!argp)
+		return -EINVAL;
+
+	q = bdev_get_queue(bdev);
+	if (!q)
+		return -ENXIO;
+
+	if (!blk_queue_is_zoned(q))
+		return -ENOTTY;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	if (!(mode & FMODE_WRITE))
+		return -EBADF;
+
+	if (copy_from_user(&zmgmt, argp, sizeof(struct blk_zone_mgmt)))
+		return -EFAULT;
+
+	switch (zmgmt.action) {
+	case BLK_ZONE_MGMT_CLOSE:
+		op = REQ_OP_ZONE_CLOSE;
+		break;
+	case BLK_ZONE_MGMT_FINISH:
+		op = REQ_OP_ZONE_FINISH;
+		break;
+	case BLK_ZONE_MGMT_OPEN:
+		op = REQ_OP_ZONE_OPEN;
+		break;
+	case BLK_ZONE_MGMT_RESET:
+		op = REQ_OP_ZONE_RESET;
+		break;
+	default:
+		return -ENOTTY;
+	}
+
+	return blkdev_zone_mgmt(bdev, op, zmgmt.sector, zmgmt.nr_sectors,
+				GFP_KERNEL);
+}
+
 static inline unsigned long *blk_alloc_zone_bitmap(int node,
 						   unsigned int nr_zones)
 {
diff --git a/block/ioctl.c b/block/ioctl.c
index bdb3bbb253d9..0ea29754e7dd 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -514,6 +514,8 @@ static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
 	case BLKOPENZONE:
 	case BLKCLOSEZONE:
 	case BLKFINISHZONE:
+		return blkdev_zone_ops_ioctl(bdev, mode, cmd, arg);
+	case BLKMGMTZONE:
 		return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
 	case BLKGETZONESZ:
 		return put_uint(argp, bdev_zone_sectors(bdev));
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8fd900998b4e..bd8521f94dc4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -368,6 +368,8 @@ int blk_revalidate_disk_zones(struct gendisk *disk,
 
 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
 				     unsigned int cmd, unsigned long arg);
+extern int blkdev_zone_ops_ioctl(struct block_device *bdev, fmode_t mode,
+				  unsigned int cmd, unsigned long arg);
 extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
 				  unsigned int cmd, unsigned long arg);
 
@@ -385,6 +387,13 @@ static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
 	return -ENOTTY;
 }
 
+
+static inline int blkdev_zone_ops_ioctl(struct block_device *bdev, fmode_t mode,
+					unsigned int cmd, unsigned long arg)
+{
+	return -ENOTTY;
+}
+
 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
 					 fmode_t mode, unsigned int cmd,
 					 unsigned long arg)
diff --git a/include/uapi/linux/blkzoned.h b/include/uapi/linux/blkzoned.h
index 42c3366cc25f..07b5fde21d9f 100644
--- a/include/uapi/linux/blkzoned.h
+++ b/include/uapi/linux/blkzoned.h
@@ -142,6 +142,38 @@ struct blk_zone_range {
 	__u64		nr_sectors;
 };
 
+/**
+ * enum blk_zone_action - Zone state transitions managed from user-space
+ *
+ * @BLK_ZONE_MGMT_CLOSE: Transition to Closed state
+ * @BLK_ZONE_MGMT_FINISH: Transition to Finish state
+ * @BLK_ZONE_MGMT_OPEN: Transition to Open state
+ * @BLK_ZONE_MGMT_RESET: Transition to Reset state
+ */
+enum blk_zone_action {
+	BLK_ZONE_MGMT_CLOSE	= 0x1,
+	BLK_ZONE_MGMT_FINISH	= 0x2,
+	BLK_ZONE_MGMT_OPEN	= 0x3,
+	BLK_ZONE_MGMT_RESET	= 0x4,
+};
+
+/**
+ * struct blk_zone_mgmt - Extended zoned management
+ *
+ * @action: Zone action as in described in enum blk_zone_action
+ * @flags: Flags for the action
+ * @sector: Starting sector of the first zone to operate on
+ * @nr_sectors: Total number of sectors of all zones to operate on
+ */
+struct blk_zone_mgmt {
+	__u8		action;
+	__u8		resv3[3];
+	__u32		flags;
+	__u64		sector;
+	__u64		nr_sectors;
+	__u64		resv31;
+};
+
 /**
  * Zoned block device ioctl's:
  *
@@ -166,5 +198,6 @@ struct blk_zone_range {
 #define BLKOPENZONE	_IOW(0x12, 134, struct blk_zone_range)
 #define BLKCLOSEZONE	_IOW(0x12, 135, struct blk_zone_range)
 #define BLKFINISHZONE	_IOW(0x12, 136, struct blk_zone_range)
+#define BLKMGMTZONE	_IOR(0x12, 137, struct blk_zone_mgmt)
 
 #endif /* _UAPI_BLKZONED_H */
-- 
2.17.1