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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] .TH DEVMAP_SETUP 9F "Jan 22, 1997" .SH NAME devmap_setup, ddi_devmap_segmap \- set up a user mapping to device memory using the devmap framework .SH SYNOPSIS .nf #include #include \fBint\fR \fBdevmap_setup\fR(\fBdev_t\fR \fIdev\fR, \fBoffset_t\fR \fIoff\fR, \fBddi_as_handle_t\fR \fIas\fR, \fBcaddr_t *\fR\fIaddrp\fR, \fBsize_t\fR\fIlen\fR, \fBuint_t\fR \fIprot\fR, \fBuint_t\fR \fImaxprot\fR, \fBuint_t\fR \fIflags\fR, \fBcred_t *\fR\fIcred\fR); .fi .LP .nf \fBint\fR \fBddi_devmap_segmap\fR(\fBdev_t\fR \fIdev\fR, \fBoff_t\fR \fIoff\fR, \fBddi_as_handle_t\fR \fIas\fR, \fBcaddr_t *\fR\fIaddrp\fR, \fBoff_t\fR\fIlen\fR, \fBuint_t\fR \fIprot\fR, \fBuint_t\fR \fImaxprot\fR, \fBuint_t\fR \fIflags\fR, \fBcred_t *\fR\fIcred\fR); .fi .SH INTERFACE LEVEL illumos DDI specific (illumos DDI). .SH PARAMETERS .ne 2 .na \fB\fIdev\fR \fR .ad .RS 12n Device whose memory is to be mapped. .RE .sp .ne 2 .na \fB\fIoff\fR \fR .ad .RS 12n User offset within the logical device memory at which the mapping begins. .RE .sp .ne 2 .na \fB\fIas\fR \fR .ad .RS 12n An opaque data structure that describes the address space into which the device memory should be mapped. .RE .sp .ne 2 .na \fB\fIaddrp\fR \fR .ad .RS 12n Pointer to the starting address in the address space into which the device memory should be mapped. .RE .sp .ne 2 .na \fB\fIlen\fR \fR .ad .RS 12n Length (in bytes) of the memory to be mapped. .RE .sp .ne 2 .na \fB\fIprot\fR \fR .ad .RS 12n A bit field that specifies the protections. Some possible settings combinations are: .sp .ne 2 .na \fB\fBPROT_READ\fR \fR .ad .RS 15n Read access is desired. .RE .sp .ne 2 .na \fB\fBPROT_WRITE\fR \fR .ad .RS 15n Write access is desired. .RE .sp .ne 2 .na \fB\fBPROT_EXEC\fR \fR .ad .RS 15n Execute access is desired. .RE .sp .ne 2 .na \fB\fBPROT_USER\fR \fR .ad .RS 15n User-level access is desired (the mapping is being done as a result of a \fBmmap\fR(2) system call). .RE .sp .ne 2 .na \fB\fBPROT_ALL\fR \fR .ad .RS 15n All access is desired. .RE .RE .sp .ne 2 .na \fB\fImaxprot\fR \fR .ad .RS 12n Maximum protection flag possible for attempted mapping; the \fBPROT_WRITE\fR bit may be masked out if the user opened the special file read-only. .RE .sp .ne 2 .na \fB\fIflags\fR \fR .ad .RS 12n Flags indicating type of mapping. The following flags can be specified: .sp .ne 2 .na \fB\fBMAP_PRIVATE\fR \fR .ad .RS 16n Changes are private. .RE .sp .ne 2 .na \fB\fBMAP_SHARED\fR \fR .ad .RS 16n Changes should be shared. .RE .sp .ne 2 .na \fB\fBMAP_FIXED\fR \fR .ad .RS 16n The user specified an address in \fI*addrp\fR rather than letting the system choose an address. .RE .RE .sp .ne 2 .na \fB\fIcred\fR \fR .ad .RS 12n Pointer to the user credential structure. .RE .SH DESCRIPTION \fBdevmap_setup()\fR and \fBddi_devmap_segmap()\fR allow device drivers to use the devmap framework to set up user mappings to device memory. The devmap framework provides several advantages over the default device mapping framework that is used by \fBddi_segmap\fR(9F) or \fBddi_segmap_setup\fR(9F). Device drivers should use the devmap framework, if the driver wants to: .RS +4 .TP .ie t \(bu .el o use an optimal MMU pagesize to minimize address translations, .RE .RS +4 .TP .ie t \(bu .el o conserve kernel resources, .RE .RS +4 .TP .ie t \(bu .el o receive callbacks to manage events on the mapping, .RE .RS +4 .TP .ie t \(bu .el o export kernel memory to applications, .RE .RS +4 .TP .ie t \(bu .el o set up device contexts for the user mapping if the device requires context switching, .RE .RS +4 .TP .ie t \(bu .el o assign device access attributes to the user mapping, or .RE .RS +4 .TP .ie t \(bu .el o change the maximum protection for the mapping. .RE .sp .LP \fBdevmap_setup()\fR must be called in the \fBsegmap\fR(9E) entry point to establish the mapping for the application. \fBddi_devmap_segmap()\fR can be called in, or be used as, the \fBsegmap\fR(9E) entry point. The differences between \fBdevmap_setup()\fR and \fBddi_devmap_segmap()\fR are in the data type used for \fIoff\fR and \fIlen\fR. .sp .LP When setting up the mapping, \fBdevmap_setup()\fR and \fBddi_devmap_segmap()\fR call the \fBdevmap\fR(9E) entry point to validate the range to be mapped. The \fBdevmap\fR(9E) entry point also translates the logical offset (as seen by the application) to the corresponding physical offset within the device address space. If the driver does not provide its own \fBdevmap\fR(9E) entry point, \fBEINVAL\fR will be returned to the \fBmmap\fR(2) system call. .SH RETURN VALUES .ne 2 .na \fB\fB0\fR \fR .ad .RS 12n Successful completion. .RE .sp .ne 2 .na \fB\fBNon-zero\fR\fR .ad .RS 12n An error occurred. The return value of \fBdevmap_setup()\fR and \fBddi_devmap_segmap()\fR should be used directly in the \fBsegmap\fR(9E) entry point. .RE .SH CONTEXT \fBdevmap_setup()\fR and \fBddi_devmap_segmap()\fR can be called from user or kernel context only. .SH SEE ALSO .BR mmap (2), .BR devmap (9E), .BR segmap (9E), .BR ddi_segmap (9F), .BR ddi_segmap_setup (9F), .BR cb_ops (9S) .sp .LP \fIWriting Device Drivers\fR