ddi_btop(9f) [linux man page]
ddi_btop(9F) Kernel Functions for Drivers ddi_btop(9F) NAME
ddi_btop, ddi_btopr, ddi_ptob - page size conversions SYNOPSIS
#include <sys/ddi.h> #include <sys/sunddi.h> unsigned long ddi_btop(dev_info_t *dip, unsigned long bytes); unsigned long ddi_btopr(dev_info_t *dip, unsigned long bytes); unsigned long ddi_ptob(dev_info_t *dip, unsigned long pages); INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). DESCRIPTION
This set of routines use the parent nexus driver to perform conversions in page size units. ddi_btop() converts the given number of bytes to the number of memory pages that it corresponds to, rounding down in the case that the byte count is not a page multiple. ddi_btopr() converts the given number of bytes to the number of memory pages that it corresponds to, rounding up in the case that the byte count is not a page multiple. ddi_ptob() converts the given number of pages to the number of bytes that it corresponds to. Because bus nexus may possess their own hardware address translation facilities, these routines should be used in preference to the corre- sponding DDI/DKI routines btop(9F), btopr(9F), and ptob(9F), which only deal in terms of the pagesize of the main system MMU. RETURN VALUES
ddi_btop() and ddi_btopr() return the number of corresponding pages. ddi_ptob() returns the corresponding number of bytes. There are no error return values. CONTEXT
This function can be called from user or interrupt context. EXAMPLES
Example 1: Find the size (in bytes) of one page pagesize = ddi_ptob(dip, 1L); SEE ALSO
btop(9F), btopr(9F), ptob(9F) Writing Device Drivers SunOS 5.10 11 Sep 1991 ddi_btop(9F)
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ddi_poke(9F) Kernel Functions for Drivers ddi_poke(9F) NAME
ddi_poke, ddi_poke8, ddi_poke16, ddi_poke32, ddi_poke64, ddi_pokec, ddi_pokes, ddi_pokel, ddi_poked - write a value to a location SYNOPSIS
#include <sys/ddi.h> #include <sys/sunddi.h> int ddi_poke8(dev_info_t *dip, int8_t *addr, int8_t value); int ddi_poke16(dev_info_t *dip, int16_t *addr, int16_t value); int ddi_poke32(dev_info_t *dip, int32_t *addr, int32_t value); int ddi_poke64(dev_info_t *dip, int64_t *addr, int64_t value); INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). The ddi_pokec(), ddi_pokes(), ddi_pokel(), and ddi_poked() functions are obsolete. Use, respectively, ddi_poke8(), ddi_poke16(), ddi_poke32(), and ddi_poke64(), instead. PARAMETERS
dip A pointer to the device's dev_info structure. addr Virtual address of the location to be written to. value Value to be written to the location. DESCRIPTION
These routines cautiously attempt to write a value to a specified virtual address, using the parent nexus driver to assist in the process where necessary. If the address is not valid, or the value cannot be written without an error occurring, an error code is returned. These routines are most useful when first trying to establish the presence of a given device on the system in a driver's probe(9E) or attach(9E) routines. On multiprocessing machines these routines can be extremely heavy-weight, so use the ddi_peek(9F) routines instead if possible. RETURN VALUES
DDI_SUCCESS The value was successfully written to the given virtual address. DDI_FAILURE An error occurred while trying to write to the location. CONTEXT
These functions can be called from user or interrupt context. SEE ALSO
attach(9E), probe(9E), ddi_peek(9F) Writing Device Drivers NOTES
The functions described in this manual page previously used symbolic names which specified their data access size; the function names have been changed so they now specify a fixed-width data size. See the following table for the new name equivalents: +-----------------------------------------------------------+ |Previous Name New Name | | ddi_pokec ddi_poke8 | | ddi_pokes ddi_poke16 | | ddi_pokel ddi_poke32 | | ddi_poked ddi_poke64 | +-----------------------------------------------------------+ SunOS 5.10 27 Sep 2002 ddi_poke(9F)