usr/src/uts/common/sys/copyops.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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #ifndef _SYS_COPYOPS_H
  28 #define _SYS_COPYOPS_H
  29
  30 #include <sys/types.h>
  31 #include <sys/thread.h>
  32 #include <sys/buf.h>
  33 #include <sys/aio_req.h>
  34 #include <sys/uio.h>
  35
  36 #ifdef  __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 #ifdef _KERNEL
  41
  42 /*
  43  * Copy in/out vector operations.  This structure is used to interpose
  44  * on the kernel copyin/copyout/etc. operations for various purposes
  45  * such as handling watchpoints in the affected user memory.  When one of the
  46  * copy operations causes a fault, the corresponding function in this vector is
  47  * called to handle it.
  48  *
  49  * The 64-bit operations in the structure fetch and store extended
  50  * words and are only used on platforms with 64 bit general
  51  * registers e.g. sun4u.
  52  *
  53  * Since the only users of these interfaces (watchpoints and pxfs) perform the
  54  * default action unless there is a page fault, we can save the overhead of
  55  * having to go through this indirection unless there is a page fault.  This
  56  * improves performance both in general and when watchpoints are enabled.  If,
  57  * in the future, a consumer relies on being able to interpose on all actions,
  58  * then this assumption will have to be undone.
  59  *
  60  * No consumers should call these functions directly.  They are automatically
  61  * handled by the generic versions.
  62  */
  63 typedef struct copyops {
  64         /*
  65          * unstructured byte copyin/out functions
  66          */
  67         int     (*cp_copyin)(const void *, void *, size_t);
  68         int     (*cp_xcopyin)(const void *, void *, size_t);
  69         int     (*cp_copyout)(const void *, void *, size_t);
  70         int     (*cp_xcopyout)(const void *, void *, size_t);
  71         int     (*cp_copyinstr)(const char *, char *, size_t, size_t *);
  72         int     (*cp_copyoutstr)(const char *, char *, size_t, size_t *);
  73
  74         /*
  75          * fetch/store byte/halfword/word/extended word
  76          */
  77         int     (*cp_fuword8)(const void *, uint8_t *);
  78         int     (*cp_fuword16)(const void *, uint16_t *);
  79         int     (*cp_fuword32)(const void *, uint32_t *);
  80         int     (*cp_fuword64)(const void *, uint64_t *);
  81
  82         int     (*cp_suword8)(void *, uint8_t);
  83         int     (*cp_suword16)(void *, uint16_t);
  84         int     (*cp_suword32)(void *, uint32_t);
  85         int     (*cp_suword64)(void *, uint64_t);
  86
  87         int     (*cp_physio)(int (*)(struct buf *), struct buf *, dev_t,
  88             int, void (*)(struct buf *), struct uio *);
  89 } copyops_t;
  90
  91 extern int      default_physio(int (*)(struct buf *), struct buf *,
  92     dev_t, int, void (*)(struct buf *), struct uio *);
  93
  94 /*
  95  * Interfaces for installing and removing copyops.
  96  */
  97 extern void install_copyops(kthread_id_t tp, copyops_t *cp);
  98 extern void remove_copyops(kthread_id_t tp);
  99 extern int copyops_installed(kthread_id_t tp);
 100
 101 #endif  /* _KERNEL */
 102
 103 #ifdef  __cplusplus
 104 }
 105 #endif
 106
 107 #endif /* _SYS_COPYOPS_H */