PSARC 2009/646 bd - generic block device driver

PSARC 2009/648 sdcard conversion to bd, EOF blk2scsa
6952618 deliver blkdev (PSARC 2009/646)

1 files changed, 155 insertions, 0 deletions

diff --git a/usr/src/uts/common/sys/blkdev.h b/usr/src/uts/common/sys/blkdev.h
new file mode 100644
index 0000000000..0ecfbb4827
--- /dev/null
+++ b/usr/src/uts/common/sys/blkdev.h
@@ -0,0 +1,155 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef	_SYS_BLKDEV_H
+#define	_SYS_BLKDEV_H
+
+#include <sys/types.h>
+#include <sys/ksynch.h>
+#include <sys/ddi.h>
+#include <sys/sunddi.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * This describes a fairly simple block device.  The idea here is that
+ * these things want to take advantage of the common labelling support,
+ * but do not need all the capabilities of SCSA.  So we make quite a few
+ * simplifications:
+ *
+ * 1) Device block size is fixed at 512 bytes.  (Devices with larger
+ *    block sizes can still operate, but will need to support some
+ *    form of read-modify-write, and will take a performance penalty.)
+ *
+ * 2) Non-rotating media.  We assume a simple linear layout.
+ *
+ * 3) Fixed queue depth, for each device.  The adapter driver reports
+ *    the queue depth at registration.  We don't have any form of
+ *    dynamic flow control.
+ *
+ * 4) Negligible power management support.  The framework does not support
+ *    fine grained power management.  If the adapter driver wants to use
+ *    such, it will need to manage power on its own.
+ *
+ * 5) Suspend/resume support managed by the adapter driver.  We don't
+ *    support suspend/resume directly.  The adapter device driver will
+ *    need to manage this on its own behalf.
+ *
+ * 6) No request priorities.  Transfers are assumed to execute in
+ *    roughly FIFO order.  The adapter driver may reorder them, but the
+ *    submitter has no control over that.
+ *
+ * 7) No request cancellation.  Once submitted, the job completes or
+ *    fails.  It cannot be canceled.
+ *
+ * 8) Limited support for removable media.  There is no support for
+ *    locking bay doors or mechanised media bays.  This could be
+ *    added, but at present the only such interesting devices are
+ *    covered by the SCSI disk driver.
+ */
+
+typedef struct bd_handle *bd_handle_t;
+typedef struct bd_xfer bd_xfer_t;
+typedef struct bd_drive bd_drive_t;
+typedef struct bd_media bd_media_t;
+typedef struct bd_ops bd_ops_t;
+
+
+struct bd_xfer {
+	/*
+	 * NB: If using DMA the br_ndmac will be non-zero.  Otherwise
+	 * the br_kaddr will be non-NULL.
+	 */
+	diskaddr_t		x_blkno;
+	size_t			x_nblks;
+	ddi_dma_handle_t	x_dmah;
+	ddi_dma_cookie_t	x_dmac;
+	unsigned		x_ndmac;
+	caddr_t			x_kaddr;
+};
+
+#define	BD_XFER_POLL		(1U << 0)	/* no interrupts (dump) */
+
+struct bd_drive {
+	uint32_t		d_qsize;
+	uint32_t		d_maxxfer;
+	boolean_t		d_removable;
+	boolean_t		d_hotpluggable;
+	int			d_target;
+	int			d_lun;
+};
+
+struct bd_media {
+	/*
+	 * NB: The block size must be a power of two not less than
+	 * DEV_BSIZE (512).  Other values of the block size will
+	 * simply not function and the media will be rejected.
+	 *
+	 * The block size must also divide evenly into the device's
+	 * d_maxxfer field.  If the maxxfer is a power of two larger
+	 * than the block size, then this will automatically be
+	 * satisfied.
+	 */
+	uint64_t		m_nblks;
+	uint32_t		m_blksize;
+	boolean_t		m_readonly;
+};
+
+#define	BD_INFO_FLAG_REMOVABLE		(1U << 0)
+#define	BD_INFO_FLAG_HOTPLUGGABLE	(1U << 1)
+#define	BD_INFO_FLAG_READ_ONLY		(1U << 2)
+
+struct bd_ops {
+	int	o_version;
+	void	(*o_drive_info)(void *, bd_drive_t *);
+	int	(*o_media_info)(void *, bd_media_t *);
+	int	(*o_devid_init)(void *, dev_info_t *, ddi_devid_t *);
+	int	(*o_sync_cache)(void *, bd_xfer_t *);
+	int	(*o_read)(void *, bd_xfer_t *);
+	int	(*o_write)(void *, bd_xfer_t *);
+	int	(*o_dump)(void *, bd_xfer_t *);
+};
+
+#define	BD_OPS_VERSION_0		0
+
+/*
+ * Note, one handler *per* address.  Drivers with multiple targets at
+ * different addresses must use separate handles.
+ */
+bd_handle_t	bd_alloc_handle(void *, bd_ops_t *, ddi_dma_attr_t *, int);
+void		bd_free_handle(bd_handle_t);
+int		bd_attach_handle(dev_info_t *, bd_handle_t);
+int		bd_detach_handle(bd_handle_t);
+void		bd_state_change(bd_handle_t);
+void		bd_xfer_done(bd_xfer_t *, int);
+void		bd_mod_init(struct dev_ops *);
+void		bd_mod_fini(struct dev_ops *);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _SYS_BLKDEV_H */