'\" te .\" Copyright 1989 AT&T .\" Portions Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. .TH ddi_copyout 9F "24 Sep 2015" "SunOS 5.11" "Kernel Functions for Drivers" .SH NAME ddi_copyout \- copy data from a driver .SH SYNOPSIS .LP .nf #include #include #include \fBint\fR \fBddi_copyout\fR(\fBconst void *\fR\fIdriverbuf\fR, \fBvoid *\fR\fIbuf\fR, \fBsize_t\fR \fIcn\fR, \fBint\fR \fIflags\fR); .fi .SH INTERFACE LEVEL .sp .LP Solaris DDI specific (Solaris DDI). .SH PARAMETERS .sp .ne 2 .mk .na \fB\fIdriverbuf\fR\fR .ad .RS 13n .rt Source address in the driver from which the data is transferred. .RE .sp .ne 2 .mk .na \fB\fIbuf\fR\fR .ad .RS 13n .rt Destination address to which the data is transferred. .RE .sp .ne 2 .mk .na \fB\fIcn\fR\fR .ad .RS 13n .rt Number of bytes to copy. .RE .sp .ne 2 .mk .na \fB\fIflags\fR\fR .ad .RS 13n .rt Set of flag bits that provide address space information about \fIbuf\fR. .RE .SH DESCRIPTION .sp .LP This routine is designed for use in driver \fBioctl\fR(9E) routines for drivers that support layered ioctls. \fBddi_copyout()\fR copies data from a driver buffer to a destination address, \fIbuf\fR. .sp .LP The \fIflags\fR argument determines the address space information about \fIbuf\fR. If the \fBFKIOCTL\fR flag is set, this indicates that \fIbuf\fR is a kernel address, and \fBddi_copyout()\fR behaves like \fBbcopy\fR(9F). Otherwise, \fIbuf\fR is interpreted as a user buffer address, and \fBddi_copyout()\fR behaves like \fBcopyout\fR(9F). .sp .LP Addresses that are word-aligned are moved most efficiently. However, the driver developer is not obliged to ensure alignment. This function automatically finds the most efficient move algorithm according to address alignment. .SH RETURN VALUES .sp .LP Under normal conditions, \fB0\fR is returned to indicate a successful copy. Otherwise, \(mi\fB1\fR is returned if one of the following occurs: .RS +4 .TP .ie t \(bu .el o Paging fault; the driver tried to access a page of memory for which it did not have read or write access. .RE .RS +4 .TP .ie t \(bu .el o Invalid user address, such as a user area or stack area. .RE .RS +4 .TP .ie t \(bu .el o Invalid address that would have resulted in data being copied into the user block. .RE .RS +4 .TP .ie t \(bu .el o Hardware fault; a hardware error prevented access to the specified user memory. For example, an uncorrectable parity or \fBECC\fR error occurred. .RE .RS +4 .TP .ie t \(bu .el o ADI version mismatch; the hardware detected a mismatch between the version specified for the destination address and the actual in-memory version. For more information, see the \fBadi\fR(3C) man page. .RE .sp .LP If \(mi\fB1\fR is returned to the caller, driver entry point routines should return \fBEFAULT\fR. .SH CONTEXT .sp .LP \fBddi_copyout()\fR can be called from user or kernel context only. .SH EXAMPLES .LP \fBExample 1 \fR\fBddi_copyout()\fR example .sp .LP A driver \fBioctl\fR(9E) routine (line 12) can be used to get or set device attributes or registers. In the \fBXX_GETREGS\fR condition (line 25), the driver copies the current device register values to another data area. If the specified argument contains an invalid address, an error code is returned. .sp .in +2 .nf 1 struct device { /* layout of physical device registers */ 2 int control; /* physical device control word */ 3 int status; /* physical device status word */ 4 short recv_char; /* receive character from device */ 5 short xmit_char; /* transmit character to device */ 6 }; 7 struct device_state { 8 volatile struct device *regsp; /* pointer to device registers */ 9 kmutex_t reg_mutex; /* protect device registers */ . . . 10 }; 11 static void *statep; /* for soft state routines */ 12 xxioctl(dev_t dev, int cmd, int arg, int mode, 13 cred_t *cred_p, int *rval_p) 14 { 15 struct device_state *sp; 16 volatile struct device *rp; 17 struct device reg_buf; /* temporary buffer for registers */ 18 int instance; 19 instance = getminor(dev); 20 sp = ddi_get_soft_state(statep, instance); 21 if (sp == NULL) 22 return (ENXIO); 23 rp = sp->regsp; . . . 24 switch (cmd) { 25 case XX_GETREGS: /* copy registers to arg */ 26 mutex_enter(&sp->reg_mutex); 27 /* 28 * Copy data from device registers to 29 * temporary device register buffer 30 * e.g. reg_buf.control = rp->control; 31 */ 32 mutex_exit(&sp->reg_mutex); 33 if (ddi_copyout(®_buf, arg, 34 sizeof (struct device), mode) != 0) { 35 return (EFAULT); 36 } 37 break; 38 } 39 } .fi .in -2 .SH SEE ALSO .sp .LP \fBioctl\fR(9E), \fBbcopy\fR(9F), \fBcopyin\fR(9F), \fBcopyout\fR(9F), \fBddi_copyin\fR(9F), \fBuiomove\fR(9F) .sp .LP \fIWriting Device Drivers for Oracle Solaris 11.2\fR .SH NOTES .sp .LP The value of the \fIflags\fR argument to \fBddi_copyout()\fR should be passed through directly from the \fImode\fR argument of \fBioctl()\fR untranslated. .sp .LP Driver defined locks should not be held across calls to this function. .sp .LP \fBddi_copyout()\fR should not be used from a streams driver. See \fBM_COPYIN\fR and \fBM_COPYOUT\fR in \fISTREAMS Programming Guide\fR.