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 2014 Garrett D'Amore <garrett@damore.org>
  23  *
  24  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27 
  28 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  29 /*        All Rights Reserved   */
  30 
  31 /*
  32  * University Copyright- Copyright (c) 1982, 1986, 1988
  33  * The Regents of the University of California
  34  * All Rights Reserved
  35  *
  36  * University Acknowledgment- Portions of this document are derived from
  37  * software developed by the University of California, Berkeley, and its
  38  * contributors.
  39  */
  40 
  41 #ifndef _SYS_UIO_H
  42 #define _SYS_UIO_H
  43 
  44 #include <sys/feature_tests.h>
  45 
  46 #ifdef  __cplusplus
  47 extern "C" {
  48 #endif
  49 
  50 #include <sys/types.h>
  51 
  52 /*
  53  * I/O parameter information.  A uio structure describes the I/O which
  54  * is to be performed by an operation.  Typically the data movement will
  55  * be performed by a routine such as uiomove(), which updates the uio
  56  * structure to reflect what was done.
  57  */
  58 
  59 #if     defined(_XPG4_2)
  60 typedef struct iovec {
  61         void    *iov_base;
  62         size_t  iov_len;
  63 } iovec_t;
  64 #else
  65 typedef struct iovec {
  66         caddr_t iov_base;
  67 #if defined(_LP64)
  68         size_t  iov_len;
  69 #else
  70         long    iov_len;
  71 #endif
  72 } iovec_t;
  73 #endif  /* defined(_XPG4_2) */
  74 
  75 #if defined(_SYSCALL32)
  76 
  77 /* Kernel's view of user ILP32 iovec struct */
  78 
  79 typedef struct iovec32 {
  80         caddr32_t       iov_base;
  81         int32_t         iov_len;
  82 } iovec32_t;
  83 
  84 #endif  /* _SYSCALL32 */
  85 
  86 #if     !defined(_XPG4_2) || defined(__EXTENSIONS__)
  87 /*
  88  * Segment flag values.
  89  */
  90 typedef enum uio_seg { UIO_USERSPACE, UIO_SYSSPACE, UIO_USERISPACE } uio_seg_t;
  91 
  92 typedef struct uio {
  93         iovec_t         *uio_iov;       /* pointer to array of iovecs */
  94         int             uio_iovcnt;     /* number of iovecs */
  95         lloff_t         _uio_offset;    /* file offset */
  96         uio_seg_t       uio_segflg;     /* address space (kernel or user) */
  97         uint16_t        uio_fmode;      /* file mode flags */
  98         uint16_t        uio_extflg;     /* extended flags */
  99         lloff_t         _uio_limit;     /* u-limit (maximum byte offset) */
 100         ssize_t         uio_resid;      /* residual count */
 101 } uio_t;
 102 
 103 /*
 104  * Extended uio_t uioa_t used for asynchronous uio.
 105  *
 106  * Note: UIOA_IOV_MAX is defined and used as it is in "fs/vncalls.c"
 107  *       as there isn't a formal definition of IOV_MAX for the kernel.
 108  */
 109 #define UIOA_IOV_MAX    16
 110 
 111 typedef struct uioa_page_s {            /* locked uio_iov state */
 112         int     uioa_pfncnt;            /* count of pfn_t(s) in *uioa_ppp */
 113         void    **uioa_ppp;             /* page_t or pfn_t arrary */
 114         caddr_t uioa_base;              /* address base */
 115         size_t  uioa_len;               /* span length */
 116 } uioa_page_t;
 117 
 118 typedef struct uioa_s {
 119         iovec_t         *uio_iov;       /* pointer to array of iovecs */
 120         int             uio_iovcnt;     /* number of iovecs */
 121         lloff_t         _uio_offset;    /* file offset */
 122         uio_seg_t       uio_segflg;     /* address space (kernel or user) */
 123         uint16_t        uio_fmode;      /* file mode flags */
 124         uint16_t        uio_extflg;     /* extended flags */
 125         lloff_t         _uio_limit;     /* u-limit (maximum byte offset) */
 126         ssize_t         uio_resid;      /* residual count */
 127         /*
 128          * uioa extended members.
 129          */
 130         uint32_t        uioa_state;     /* state of asynch i/o */
 131         ssize_t         uioa_mbytes;    /* bytes that have been uioamove()ed */
 132         uioa_page_t     *uioa_lcur;     /* pointer into uioa_locked[] */
 133         void            **uioa_lppp;    /* pointer into lcur->uioa_ppp[] */
 134         void            *uioa_hwst[4];  /* opaque hardware state */
 135         uioa_page_t     uioa_locked[UIOA_IOV_MAX]; /* Per iov locked pages */
 136 } uioa_t;
 137 
 138 /*
 139  * uio extensions
 140  *
 141  * PSARC 2009/478: Copy Reduction Interfaces
 142  */
 143 typedef enum xuio_type {
 144         UIOTYPE_ASYNCIO,
 145         UIOTYPE_ZEROCOPY
 146 } xuio_type_t;
 147 
 148 typedef struct xuio {
 149         uio_t xu_uio;           /* Embedded UIO structure */
 150 
 151         /* Extended uio fields */
 152         enum xuio_type xu_type; /* What kind of uio structure? */
 153         union {
 154                 /* Async I/O Support, intend to replace uioa_t. */
 155                 struct {
 156                         uint32_t xu_a_state;    /* state of async i/o */
 157                         /* bytes that have been uioamove()ed */
 158                         ssize_t xu_a_mbytes;
 159                         uioa_page_t *xu_a_lcur; /* pointer into uioa_locked[] */
 160                         /* pointer into lcur->uioa_ppp[] */
 161                         void **xu_a_lppp;
 162                         void *xu_a_hwst[4];     /* opaque hardware state */
 163                         /* Per iov locked pages */
 164                         uioa_page_t xu_a_locked[UIOA_IOV_MAX];
 165                 } xu_aio;
 166 
 167                 /*
 168                  * Copy Reduction Support -- facilate loaning / returning of
 169                  * filesystem cache buffers.
 170                  */
 171                 struct {
 172                         int xu_zc_rw;   /* read or write buffer */
 173                         void *xu_zc_priv;       /* fs specific */
 174                 } xu_zc;
 175         } xu_ext;
 176 } xuio_t;
 177 
 178 #define XUIO_XUZC_PRIV(xuio)    xuio->xu_ext.xu_zc.xu_zc_priv
 179 #define XUIO_XUZC_RW(xuio)      xuio->xu_ext.xu_zc.xu_zc_rw
 180 
 181 #define UIOA_ALLOC      0x0001          /* allocated but not yet initialized */
 182 #define UIOA_INIT       0x0002          /* initialized but not yet enabled */
 183 #define UIOA_ENABLED    0x0004          /* enabled, asynch i/o active */
 184 #define UIOA_FINI       0x0008          /* finished waiting for uioafini() */
 185 
 186 #define UIOA_CLR        (~0x000F)       /* clear mutually exclusive bits */
 187 
 188 #define UIOA_POLL       0x0010          /* need dcopy_poll() */
 189 
 190 #define uio_loffset     _uio_offset._f
 191 #if !defined(_LP64)
 192 #define uio_offset      _uio_offset._p._l
 193 #else
 194 #define uio_offset      uio_loffset
 195 #endif
 196 
 197 #define uio_llimit      _uio_limit._f
 198 #if !defined(_LP64)
 199 #define uio_limit       _uio_limit._p._l
 200 #else
 201 #define uio_limit       uio_llimit
 202 #endif
 203 
 204 /*
 205  * I/O direction.
 206  */
 207 typedef enum uio_rw { UIO_READ, UIO_WRITE } uio_rw_t;
 208 
 209 /*
 210  * uio_extflg: extended flags
 211  *
 212  * NOTE: This flag will be used in uiomove to determine if non-temporal
 213  * access, ie, access bypassing caches, should be used.  Filesystems that
 214  * don't initialize this field could experience suboptimal performance due to
 215  * the random data the field contains.
 216  *
 217  * NOTE: This flag is also used by uioasync callers to pass an extended
 218  * uio_t (uioa_t), to uioasync enabled consumers. Unlike above all
 219  * consumers of a uioa_t require the uio_extflg to be initialized.
 220  */
 221 #define UIO_COPY_DEFAULT        0x0000  /* no special options to copy */
 222 #define UIO_COPY_CACHED         0x0001  /* copy should not bypass caches */
 223 
 224 #define UIO_ASYNC               0x0002  /* uio_t is really a uioa_t */
 225 #define UIO_XUIO                0x0004  /* Structure is xuio_t */
 226 
 227 /*
 228  * Global uioasync capability shadow state.
 229  */
 230 typedef struct uioasync_s {
 231         boolean_t       enabled;        /* Is uioasync enabled? */
 232         size_t          mincnt;         /* Minimum byte count for use of */
 233 } uioasync_t;
 234 
 235 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
 236 
 237 #if     defined(_KERNEL)
 238 
 239 int     uiomove(void *, size_t, enum uio_rw, uio_t *);
 240 void    uio_prefaultpages(ssize_t, uio_t *);
 241 int     uiocopy(void *, size_t, enum uio_rw, uio_t *, size_t *);
 242 int     ureadc(int, uio_t *);   /* should be errno_t in future */
 243 int     uwritec(struct uio *);
 244 void    uioskip(uio_t *, size_t);
 245 int     uiodup(uio_t *, uio_t *, iovec_t *, int);
 246 
 247 int     uioamove(void *, size_t, enum uio_rw, uioa_t *);
 248 int     uioainit(uio_t *, uioa_t *);
 249 int     uioafini(uio_t *, uioa_t *);
 250 extern  uioasync_t uioasync;
 251 
 252 #else   /* defined(_KERNEL) */
 253 
 254 extern ssize_t readv(int, const struct iovec *, int);
 255 extern ssize_t writev(int, const struct iovec *, int);
 256 
 257 #endif  /* defined(_KERNEL) */
 258 
 259 #ifdef  __cplusplus
 260 }
 261 #endif
 262 
 263 #endif  /* _SYS_UIO_H */