ddi_prop_create(9F) Kernel Functions for Drivers ddi_prop_create(9F)NAME
ddi_prop_create, ddi_prop_modify, ddi_prop_remove, ddi_prop_remove_all,
ddi_prop_undefine - create, remove, or modify properties for leaf
device drivers
SYNOPSIS
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
int ddi_prop_create(dev_t dev, dev_info_t *dip, int flags, char *name,
caddr_t valuep, int length);
int ddi_prop_undefine(dev_t dev, dev_info_t *dip, int flags, char
*name);
int ddi_prop_modify(dev_t dev, dev_info_t *dip, int flags, char *name,
caddr_t valuep, int length);
int ddi_prop_remove(dev_t dev, dev_info_t *dip, char *name);
void ddi_prop_remove_all(dev_info_t *dip);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI). The ddi_prop_create() and
ddi_prop_modify() functions are obsolete. Use ddi_prop_update(9F)
instead of these functions.
PARAMETERSddi_prop_create()
dev dev_t of the device.
dip dev_info_t pointer of the device.
flags flag modifiers. The only possible flag value is
DDI_PROP_CANSLEEP: Memory allocation may sleep.
name name of property.
valuep pointer to property value.
length property length.
ddi_prop_undefine()
dev dev_t of the device.
dip dev_info_t pointer of the device.
flags flag modifiers. The only possible flag value is
DDI_PROP_CANSLEEP: Memory allocation may sleep.
name name of property.
ddi_prop_modify()
dev dev_t of the device.
dip dev_info_t pointer of the device.
flags flag modifiers. The only possible flag value is
DDI_PROP_CANSLEEP: Memory allocation may sleep.
name name of property.
valuep pointer to property value.
length property length.
ddi_prop_remove()
dev dev_t of the device.
dip dev_info_t pointer of the device.
name name of property.
ddi_prop_remove_all()
dip dev_info_t pointer of the device.
DESCRIPTION
Device drivers have the ability to create and manage their own proper‐
ties as well as gain access to properties that the system creates on
behalf of the driver. A driver uses ddi_getproplen(9F) to query whether
or not a specific property exists.
Property creation is done by creating a new property definition in the
driver's property list associated with dip.
Property definitions are stacked; they are added to the beginning of
the driver's property list when created. Thus, when searched for, the
most recent matching property definition will be found and its value
will be return to the caller.
The individual functions are described as follows:
ddi_prop_create()ddi_prop_create() adds a property to the device's property list. If
the property is not associated with any particular dev but is asso‐
ciated with the physical device itself, then the argument dev
should be the special device DDI_DEV_T_NONE. If you do not have a
dev for your device (for example during attach(9E) time), you can
create one using makedevice(9F) with a major number of
DDI_MAJOR_T_UNKNOWN. ddi_prop_create() will then make the correct
dev for your device.
For boolean properties, you must set length to 0. For all other
properties, the length argument must be set to the number of bytes
used by the data structure representing the property being created.
Note that creating a property involves allocating memory for the
property list, the property name and the property value. If flags
does not contain DDI_PROP_CANSLEEP, ddi_prop_create() returns
DDI_PROP_NO_MEMORY on memory allocation failure or DDI_PROP_SUCCESS
if the allocation succeeded. If DDI_PROP_CANSLEEP was set, the
caller may sleep until memory becomes available.
ddi_prop_undefine()ddi_prop_undefine() is a special case of property creation where
the value of the property is set to undefined. This property has
the effect of terminating a property search at the current devinfo
node, rather than allowing the search to proceed up to ancestor
devinfo nodes. However, ddi_prop_undefine() will not terminate a
search when the ddi_prop_get_int64(9F) or
ddi_prop_lookup_int64_array(9F) routines are used for lookup of
64-bit property value. See ddi_prop_op(9F).
Note that undefining properties does involve memory allocation, and
therefore, is subject to the same memory allocation constraints as
ddi_prop_create().
ddi_prop_modify()ddi_prop_modify() modifies the length and the value of a property.
If ddi_prop_modify() finds the property in the driver's property
list, allocates memory for the property value and returns
DDI_PROP_SUCCESS. If the property was not found, the function
returns DDI_PROP_NOT_FOUND.
Note that modifying properties does involve memory allocation, and
therefore, is subject to the same memory allocation constraints as
ddi_prop_create().
ddi_prop_remove()ddi_prop_remove() unlinks a property from the device's property
list. If ddi_prop_remove() finds the property (an exact match of
both nameand dev), it unlinks the property, frees its memory, and
returns DDI_PROP_SUCCESS, otherwise, it returns DDI_PROP_NOT_FOUND.
ddi_prop_remove_all()ddi_prop_remove_all() removes the properties of all the dev_t's
associated with the dip. It is called before unloading a driver.
RETURN VALUES
The ddi_prop_create() function returns the following values:
DDI_PROP_SUCCESS On success.
DDI_PROP_NO_MEMORY On memory allocation failure.
DDI_PROP_INVAL_ARG If an attempt is made to create a prop‐
erty with dev equal to DDI_DEV_T_ANY or
if name is NULL or name is the NULL
string.
The ddi_prop_ undefine() function returns the following values:
DDI_PROP_SUCCESS On success.
DDI_PROP_NO_MEMORY On memory allocation failure.
DDI_PROP_INVAL_ARG If an attempt is made to create a prop‐
erty with dev DDI_DEV_T_ANY or if name
is NULL or name is the NULL string.
The ddi_prop_modify() function returns the following values:
DDI_PROP_SUCCESS On success.
DDI_PROP_NO_MEMORY On memory allocation failure.
DDI_PROP_INVAL_ARG If an attempt is made to create a prop‐
erty with dev equal to DDI_DEV_T_ANY or
if name is NULL or name is the NULL
string.
DDI_PROP_NOT_FOUND On property search failure.
The ddi_prop_remove() function returns the following values:
DDI_PROP_SUCCESS On success.
DDI_PROP_INVAL_ARG If an attempt is made to create a prop‐
erty with dev equal to DDI_DEV_T_ANY or
if name is NULL or name is the NULL
string.
DDI_PROP_NOT_FOUND On property search failure.
CONTEXT
If DDI_PROP_CANSLEEP is set, these functions can cannot be called from
interrupt context. Otherwise, they can be called from user, interrupt,
or kernel context.
EXAMPLES
Example 1: Creating a Property
The following example creates a property called nblocks for each parti‐
tion on a disk.
int propval = 8192;
for (minor = 0; minor < 8; minor ++) {
(void) ddi_prop_create(makedevice(DDI_MAJOR_T_UNKNOWN, minor),
dev, DDI_PROP_CANSLEEP, "nblocks", (caddr_t) &propval,
sizeof (int));
...
}
ATTRIBUTES
See attributes(5) for a description of the following attributes:
┌────────────────────────────┬──────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────────────┼──────────────────────────────┤
│Stability Level │ ddi_prop_create() and │
│ │ ddi_prop_modify() are Obso‐ │
│ │ lete │
└────────────────────────────┴──────────────────────────────┘
SEE ALSOdriver.conf(4), attributes(5), attach(9E), ddi_getproplen(9F),
ddi_prop_op(9F), ddi_prop_update(9F), makedevice(9F)
Writing Device Drivers
SunOS 5.10 16 Jan 2006 ddi_prop_create(9F)
