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ddi_segmap(9f) [opensolaris man page]

ddi_segmap(9F)						   Kernel Functions for Drivers 					    ddi_segmap(9F)

NAME
ddi_segmap, ddi_segmap_setup - set up a user mapping using seg_dev SYNOPSIS
#include <sys/conf.h> #include <sys/ddi.h> #include <sys/sunddi.h> int ddi_segmap(dev_t dev, off_t offset, struct as *asp, caddr_t *addrp, off_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *credp); int ddi_segmap_setup(dev_t dev, off_t offset, struct as *asp, caddr_t *addrp, off_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *credp, ddi_device_acc_attr_t *accattrp, uint_t rnumber); INTERFACE LEVEL
These interfaces are obsolete. See devmap(9E) for an alternative to ddi_segmap(). Use devmap_setup(9F) instead of ddi_segmap_setup(). PARAMETERS
dev The device whose memory is to be mapped. offset The offset within device memory at which the mapping begins. asp An opaque pointer to the user address space into which the device memory should be mapped. addrp Pointer to the starting address within the user address space to which the device memory should be mapped. len Length (in bytes) of the memory to be mapped. prot A bit field that specifies the protections. Some combinations of possible settings are: PROT_READ Read access is desired. PROT_WRITE Write access is desired. PROT_EXEC Execute access is desired. PROT_USER User-level access is desired (the mapping is being done as a result of a mmap(2) system call). PROT_ALL All access is desired. maxprot Maximum protection flag possible for attempted mapping (the PROT_WRITE bit may be masked out if the user opened the special file read-only). If (maxprot & prot) != prot then there is an access violation. flags Flags indicating type of mapping. Possible values are (other bits may be set): MAP_PRIVATE Changes are private. MAP_SHARED Changes should be shared. MAP_FIXED The user specified an address in *addrp rather than letting the system pick and address. credp Pointer to user credential structure. ddi_segmap_setup() dev_acc_attr Pointer to a ddi_device_acc_attr(9S) structure which contains the device access attributes to apply to this mapping. rnumber Index number to the register address space set. DESCRIPTION
Future releases of Solaris will provide this function for binary and source compatibility. However, for increased functionality, use ddi_devmap_segmap(9F) instead. See ddi_devmap_segmap(9F) for details. ddi_segmap() and ddi_segmap_setup() set up user mappings to device space. When setting up the mapping, the ddi_segmap() and ddi_segmap_setup() routines call the mmap(9E) entry point to validate the range to be mapped. When a user process accesses the mapping, the drivers mmap(9E) entry point is again called to retrieve the page frame number that needs to be loaded. The mapping translations for that page are then loaded on behalf of the driver by the DDI framework. ddi_segmap() is typically used as the segmap(9E) entry in the cb_ops(9S) structure for those devices that do not choose to provide their own segmap(9E) entry point. However, some drivers may have their own segmap(9E) entry point to do some initial processing on the parame- ters and then call ddi_segmap() to establish the default memory mapping. ddi_segmap_setup() is used in the drivers segmap(9E) entry point to set up the mapping and assign device access attributes to that mapping. rnumber specifies the register set representing the range of device memory being mapped. See ddi_device_acc_attr(9S) for details regard- ing what device access attributes are available. ddi_segmap_setup() cannot be used directly in the cb_ops(9S) structure and requires a driver to have a segmap(9E) entry point. RETURN VALUES
ddi_segmap() and ddi_segmap_setup() return the following values: 0 Successful completion. Non-zero An error occurred. In particular, they return ENXIO if the range to be mapped is invalid. CONTEXT
ddi_segmap() and ddi_segmap_setup() can be called from user or kernel context only. ATTRIBUTES
See attributes(5) for a description of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Stability Level |Obsolete | +-----------------------------+-----------------------------+ SEE ALSO
mmap(2), attributes(5), devmap(9E), mmap(9E), segmap(9E), devmap_setup(9F), cb_ops(9S), ddi_device_acc_attr(9S) Writing Device Drivers SunOS 5.11 17 Nov 2003 ddi_segmap(9F)
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