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 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #include <sys/types.h>
  33 #include <sys/thread.h>
  34 #include <sys/buf.h>
  35 #include <sys/aio_req.h>
  36 #include <sys/uio.h>
  37
  38 #ifdef  __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 #ifdef _KERNEL
  43
  44 /*
  45  * Copy in/out vector operations.  This structure is used to interpose
  46  * on the kernel copyin/copyout/etc. operations for various purposes
  47  * such as handling watchpoints in the affected user memory.  When one of the
  48  * copy operations causes a fault, the corresponding function in this vector is
  49  * called to handle it.
  50  *
  51  * The 64-bit operations in the structure fetch and store extended
  52  * words and are only used on platforms with 64 bit general
  53  * registers e.g. sun4u.
  54  *
  55  * Since the only users of these interfaces (watchpoints and pxfs) perform the
  56  * default action unless there is a page fault, we can save the overhead of
  57  * having to go through this indirection unless there is a page fault.  This
  58  * improves performance both in general and when watchpoints are enabled.  If,
  59  * in the future, a consumer relies on being able to interpose on all actions,
  60  * then this assumption will have to be undone.
  61  *
  62  * No consumers should call these functions directly.  They are automatically
  63  * handled by the generic versions.
  64  */
  65 typedef struct copyops {
  66         /*
  67          * unstructured byte copyin/out functions
  68          */
  69         int     (*cp_copyin)(const void *, void *, size_t);
  70         int     (*cp_xcopyin)(const void *, void *, size_t);
  71         int     (*cp_copyout)(const void *, void *, size_t);
  72         int     (*cp_xcopyout)(const void *, void *, size_t);
  73         int     (*cp_copyinstr)(const char *, char *, size_t, size_t *);
  74         int     (*cp_copyoutstr)(const char *, char *, size_t, size_t *);
  75
  76         /*
  77          * fetch/store byte/halfword/word/extended word
  78          */
  79         int     (*cp_fuword8)(const void *, uint8_t *);
  80         int     (*cp_fuword16)(const void *, uint16_t *);
  81         int     (*cp_fuword32)(const void *, uint32_t *);
  82         int     (*cp_fuword64)(const void *, uint64_t *);
  83
  84         int     (*cp_suword8)(void *, uint8_t);
  85         int     (*cp_suword16)(void *, uint16_t);
  86         int     (*cp_suword32)(void *, uint32_t);
  87         int     (*cp_suword64)(void *, uint64_t);
  88
  89         int     (*cp_physio)(int (*)(struct buf *), struct buf *, dev_t,
  90             int, void (*)(struct buf *), struct uio *);
  91 } copyops_t;
  92
  93 extern int      default_physio(int (*)(struct buf *), struct buf *,
  94     dev_t, int, void (*)(struct buf *), struct uio *);
  95
  96 /*
  97  * Interfaces for installing and removing copyops.
  98  */
  99 extern void install_copyops(kthread_id_t tp, copyops_t *cp);
 100 extern void remove_copyops(kthread_id_t tp);
 101 extern int copyops_installed(kthread_id_t tp);
 102
 103 #endif  /* _KERNEL */
 104
 105 #ifdef  __cplusplus
 106 }
 107 #endif
 108
 109 #endif /* _SYS_COPYOPS_H */