uio.h revision b819cea2f73f98c5662230cc9affc8cc84f77fcf
/*
* 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 2014 Garrett D'Amore <garrett@damore.org>
*
* Copyright 2010 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* Copyright 2013 Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 2015, Joyent, Inc. All rights reserved.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#ifndef _SYS_UIO_H
#define _SYS_UIO_H
#include <sys/feature_tests.h>
#ifdef __cplusplus
extern "C" {
#endif
#include <sys/types.h>
/*
* I/O parameter information. A uio structure describes the I/O which
* is to be performed by an operation. Typically the data movement will
* be performed by a routine such as uiomove(), which updates the uio
* structure to reflect what was done.
*/
#if defined(_XPG4_2)
typedef struct iovec {
void *iov_base;
size_t iov_len;
} iovec_t;
#else
typedef struct iovec {
caddr_t iov_base;
#if defined(_LP64)
size_t iov_len;
#else
long iov_len;
#endif
} iovec_t;
#endif /* defined(_XPG4_2) */
#if defined(_SYSCALL32)
/* Kernel's view of user ILP32 iovec struct */
typedef struct iovec32 {
caddr32_t iov_base;
int32_t iov_len;
} iovec32_t;
#endif /* _SYSCALL32 */
#if !defined(_XPG4_2) || defined(__EXTENSIONS__)
/*
* Segment flag values.
*/
typedef enum uio_seg { UIO_USERSPACE, UIO_SYSSPACE, UIO_USERISPACE } uio_seg_t;
typedef struct uio {
iovec_t *uio_iov; /* pointer to array of iovecs */
int uio_iovcnt; /* number of iovecs */
lloff_t _uio_offset; /* file offset */
uio_seg_t uio_segflg; /* address space (kernel or user) */
uint16_t uio_fmode; /* file mode flags */
uint16_t uio_extflg; /* extended flags */
lloff_t _uio_limit; /* u-limit (maximum byte offset) */
ssize_t uio_resid; /* residual count */
} uio_t;
/*
* Extended uio_t uioa_t used for asynchronous uio.
*
* Note: UIOA_IOV_MAX is defined and used as it is in "fs/vncalls.c"
* as there isn't a formal definition of IOV_MAX for the kernel.
*/
#define UIOA_IOV_MAX 16
typedef struct uioa_page_s { /* locked uio_iov state */
int uioa_pfncnt; /* count of pfn_t(s) in *uioa_ppp */
void **uioa_ppp; /* page_t or pfn_t arrary */
caddr_t uioa_base; /* address base */
size_t uioa_len; /* span length */
} uioa_page_t;
typedef struct uioa_s {
iovec_t *uio_iov; /* pointer to array of iovecs */
int uio_iovcnt; /* number of iovecs */
lloff_t _uio_offset; /* file offset */
uio_seg_t uio_segflg; /* address space (kernel or user) */
uint16_t uio_fmode; /* file mode flags */
uint16_t uio_extflg; /* extended flags */
lloff_t _uio_limit; /* u-limit (maximum byte offset) */
ssize_t uio_resid; /* residual count */
/*
* uioa extended members.
*/
uint32_t uioa_state; /* state of asynch i/o */
ssize_t uioa_mbytes; /* bytes that have been uioamove()ed */
uioa_page_t *uioa_lcur; /* pointer into uioa_locked[] */
void **uioa_lppp; /* pointer into lcur->uioa_ppp[] */
void *uioa_hwst[4]; /* opaque hardware state */
uioa_page_t uioa_locked[UIOA_IOV_MAX]; /* Per iov locked pages */
} uioa_t;
/*
* uio extensions
*
* PSARC 2009/478: Copy Reduction Interfaces
*/
typedef enum xuio_type {
UIOTYPE_ASYNCIO,
UIOTYPE_ZEROCOPY
} xuio_type_t;
typedef struct xuio {
uio_t xu_uio; /* Embedded UIO structure */
/* Extended uio fields */
enum xuio_type xu_type; /* What kind of uio structure? */
union {
/* Async I/O Support, intend to replace uioa_t. */
struct {
uint32_t xu_a_state; /* state of async i/o */
/* bytes that have been uioamove()ed */
ssize_t xu_a_mbytes;
uioa_page_t *xu_a_lcur; /* pointer into uioa_locked[] */
/* pointer into lcur->uioa_ppp[] */
void **xu_a_lppp;
void *xu_a_hwst[4]; /* opaque hardware state */
/* Per iov locked pages */
uioa_page_t xu_a_locked[UIOA_IOV_MAX];
} xu_aio;
/*
* Copy Reduction Support -- facilate loaning / returning of
* filesystem cache buffers.
*/
struct {
int xu_zc_rw; /* read or write buffer */
void *xu_zc_priv; /* fs specific */
} xu_zc;
} xu_ext;
} xuio_t;
#define XUIO_XUZC_PRIV(xuio) xuio->xu_ext.xu_zc.xu_zc_priv
#define XUIO_XUZC_RW(xuio) xuio->xu_ext.xu_zc.xu_zc_rw
#define UIOA_ALLOC 0x0001 /* allocated but not yet initialized */
#define UIOA_INIT 0x0002 /* initialized but not yet enabled */
#define UIOA_ENABLED 0x0004 /* enabled, asynch i/o active */
#define UIOA_FINI 0x0008 /* finished waiting for uioafini() */
#define UIOA_CLR (~0x000F) /* clear mutually exclusive bits */
#define UIOA_POLL 0x0010 /* need dcopy_poll() */
#define uio_loffset _uio_offset._f
#if !defined(_LP64)
#define uio_offset _uio_offset._p._l
#else
#define uio_offset uio_loffset
#endif
#define uio_llimit _uio_limit._f
#if !defined(_LP64)
#define uio_limit _uio_limit._p._l
#else
#define uio_limit uio_llimit
#endif
/*
* I/O direction.
*/
typedef enum uio_rw { UIO_READ, UIO_WRITE } uio_rw_t;
/*
* uio_extflg: extended flags
*
* NOTE: This flag will be used in uiomove to determine if non-temporal
* access, ie, access bypassing caches, should be used. Filesystems that
* don't initialize this field could experience suboptimal performance due to
* the random data the field contains.
*
* NOTE: This flag is also used by uioasync callers to pass an extended
* uio_t (uioa_t), to uioasync enabled consumers. Unlike above all
* consumers of a uioa_t require the uio_extflg to be initialized.
*/
#define UIO_COPY_DEFAULT 0x0000 /* no special options to copy */
#define UIO_COPY_CACHED 0x0001 /* copy should not bypass caches */
#define UIO_ASYNC 0x0002 /* uio_t is really a uioa_t */
#define UIO_XUIO 0x0004 /* Structure is xuio_t */
/*
* Global uioasync capability shadow state.
*/
typedef struct uioasync_s {
boolean_t enabled; /* Is uioasync enabled? */
size_t mincnt; /* Minimum byte count for use of */
} uioasync_t;
#endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
#if defined(_KERNEL) || defined(_FAKE_KERNEL)
int uiomove(void *, size_t, enum uio_rw, uio_t *);
void uio_prefaultpages(ssize_t, uio_t *);
int uiocopy(void *, size_t, enum uio_rw, uio_t *, size_t *);
int ureadc(int, uio_t *); /* should be errno_t in future */
int uwritec(struct uio *);
void uioskip(uio_t *, size_t);
int uiodup(uio_t *, uio_t *, iovec_t *, int);
int uioamove(void *, size_t, enum uio_rw, uioa_t *);
int uioainit(uio_t *, uioa_t *);
int uioafini(uio_t *, uioa_t *);
extern uioasync_t uioasync;
#else /* defined(_KERNEL) */
extern ssize_t readv(int, const struct iovec *, int);
extern ssize_t writev(int, const struct iovec *, int);
/*
* When in the large file compilation environment,
* map preadv/pwritev to their 64 bit offset versions
*/
#if !defined(_LP64) && _FILE_OFFSET_BITS == 64
#ifdef __PRAGMA_REDEFINE_EXTNAME
#pragma redefine_extname preadv preadv64
#pragma redefine_extname pwritev pwritev64
#else /* __PRAGMA_REDEFINE_EXTNAME */
#define preadv preadv64
#define pwritev pwritev64
#endif /* __PRAGMA_REDEFINE_EXTNAME */
#endif /* !_LP64 && _FILE_OFFSET_BITS == 64 */
/* In the LP64 compilation environment, the APIs are already large file */
#if defined(_LP64) && defined(_LARGEFILE64_SOURCE)
#ifdef __PRAGMA_REDEFINE_EXTNAME
#pragma redefine_extname preadv64 preadv
#pragma redefine_extname pwritev64 pwritev
#else /* __PRAGMA_REDEFINE_EXTNAME */
#define preadv64 preadv
#define pwritev64 pwritev
#endif /* __PRAGMA_REDEFINE_EXTNAME */
#endif /* _LP64 && _LARGEFILE64_SOURCE */
extern ssize_t preadv(int, const struct iovec *, int, off_t);
extern ssize_t pwritev(int, const struct iovec *, int, off_t);
/*
* preadv64 and pwritev64 should be defined when:
* - Using the transitional compilation environment, and not
* the large file compilation environment.
*/
#if defined(_LARGEFILE64_SOURCE) && !((_FILE_OFFSET_BITS == 64) && \
!defined(__PRAGMA_REDEFINE_EXTNAME))
extern ssize_t preadv64(int, const struct iovec *, int, off64_t);
extern ssize_t pwritev64(int, const struct iovec *, int, off64_t);
#endif /* _LARGEFILE64_SOURCE */
#endif /* defined(_KERNEL) */
#ifdef __cplusplus
}
#endif
#endif /* _SYS_UIO_H */