usr/src/uts/common/sys/blkdev.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2012 DEY Storage Systems, Inc.  All rights reserved.
  23  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  24  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
  25  */
  26
  27 #ifndef _SYS_BLKDEV_H
  28 #define _SYS_BLKDEV_H
  29
  30 #include <sys/types.h>
  31 #include <sys/ksynch.h>
  32 #include <sys/ddi.h>
  33 #include <sys/sunddi.h>
  34
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 /*
  40  * This describes a fairly simple block device.  The idea here is that
  41  * these things want to take advantage of the common labelling support,
  42  * but do not need all the capabilities of SCSA.  So we make quite a few
  43  * simplifications:
  44  *
  45  * 1) Device block size is a power of 2 greater or equal to 512 bytes.
  46  *    An optional physical block size can be reported if the underlying
  47  *    device uses larger block sizes internally, so that writes can be
  48  *    aligned properly.
  49  *
  50  * 2) Non-rotating media.  We assume a simple linear layout.
  51  *
  52  * 3) Fixed queue depth, for each device.  The adapter driver reports
  53  *    the queue depth at registration.  We don't have any form of
  54  *    dynamic flow control.
  55  *
  56  * 4) Negligible power management support.  The framework does not support
  57  *    fine grained power management.  If the adapter driver wants to use
  58  *    such, it will need to manage power on its own.
  59  *
  60  * 5) Suspend/resume support managed by the adapter driver.  We don't
  61  *    support suspend/resume directly.  The adapter device driver will
  62  *    need to manage this on its own behalf.
  63  *
  64  * 6) No request priorities.  Transfers are assumed to execute in
  65  *    roughly FIFO order.  The adapter driver may reorder them, but the
  66  *    submitter has no control over that.
  67  *
  68  * 7) No request cancellation.  Once submitted, the job completes or
  69  *    fails.  It cannot be canceled.
  70  *
  71  * 8) Limited support for removable media.  There is no support for
  72  *    locking bay doors or mechanised media bays.  This could be
  73  *    added, but at present the only such interesting devices are
  74  *    covered by the SCSI disk driver.
  75  */
  76
  77 typedef struct bd_handle *bd_handle_t;
  78 typedef struct bd_xfer bd_xfer_t;
  79 typedef struct bd_drive bd_drive_t;
  80 typedef struct bd_media bd_media_t;
  81 typedef struct bd_ops bd_ops_t;
  82
  83
  84 struct bd_xfer {
  85         /*
  86          * NB: If using DMA the br_ndmac will be non-zero.  Otherwise
  87          * the br_kaddr will be non-NULL.
  88          */
  89         diskaddr_t              x_blkno;
  90         size_t                  x_nblks;
  91         ddi_dma_handle_t        x_dmah;
  92         ddi_dma_cookie_t        x_dmac;
  93         unsigned                x_ndmac;
  94         caddr_t                 x_kaddr;
  95         unsigned                x_flags;
  96 };
  97
  98 #define BD_XFER_POLL            (1U << 0)       /* no interrupts (dump) */
  99
 100 struct bd_drive {
 101         uint32_t                d_qsize;
 102         uint32_t                d_maxxfer;
 103         boolean_t               d_removable;
 104         boolean_t               d_hotpluggable;
 105         int                     d_target;
 106         int                     d_lun;
 107 };
 108
 109 struct bd_media {
 110         /*
 111          * NB: The block size must be a power of two not less than
 112          * DEV_BSIZE (512).  Other values of the block size will
 113          * simply not function and the media will be rejected.
 114          *
 115          * The block size must also divide evenly into the device's
 116          * d_maxxfer field.  If the maxxfer is a power of two larger
 117          * than the block size, then this will automatically be
 118          * satisfied.
 119          *
 120          * The physical block size (m_pblksize) must be 0 or a power
 121          * of two not less than the block size.
 122          */
 123         uint64_t                m_nblks;
 124         uint32_t                m_blksize;
 125         boolean_t               m_readonly;
 126         boolean_t               m_solidstate;
 127         uint32_t                m_pblksize;
 128 };
 129
 130 #define BD_INFO_FLAG_REMOVABLE          (1U << 0)
 131 #define BD_INFO_FLAG_HOTPLUGGABLE       (1U << 1)
 132 #define BD_INFO_FLAG_READ_ONLY          (1U << 2)
 133
 134 struct bd_ops {
 135         int     o_version;
 136         void    (*o_drive_info)(void *, bd_drive_t *);
 137         int     (*o_media_info)(void *, bd_media_t *);
 138         int     (*o_devid_init)(void *, dev_info_t *, ddi_devid_t *);
 139         int     (*o_sync_cache)(void *, bd_xfer_t *);
 140         int     (*o_read)(void *, bd_xfer_t *);
 141         int     (*o_write)(void *, bd_xfer_t *);
 142 };
 143
 144 #define BD_OPS_VERSION_0                0
 145
 146 /*
 147  * Note, one handler *per* address.  Drivers with multiple targets at
 148  * different addresses must use separate handles.
 149  */
 150 bd_handle_t     bd_alloc_handle(void *, bd_ops_t *, ddi_dma_attr_t *, int);
 151 void            bd_free_handle(bd_handle_t);
 152 int             bd_attach_handle(dev_info_t *, bd_handle_t);
 153 int             bd_detach_handle(bd_handle_t);
 154 void            bd_state_change(bd_handle_t);
 155 void            bd_xfer_done(bd_xfer_t *, int);
 156 void            bd_mod_init(struct dev_ops *);
 157 void            bd_mod_fini(struct dev_ops *);
 158
 159 #ifdef __cplusplus
 160 }
 161 #endif
 162
 163 #endif  /* _SYS_BLKDEV_H */