Handling Resource Allocation Failures
The resource-allocation routines provide the driver with several options
when handling allocation failures. The waitfp argument
indicates whether the allocation routines block, return immediately, or schedule
a callback, as shown in the following table.
Table 9-1 Resource Allocation Handling
| |
|---|
DDI_DMA_DONTWAIT
| Driver does not want to wait for resources to become available
|
DDI_DMA_SLEEP
| Driver is willing to wait indefinitely for resources to become available
|
Other values
| The address of a function to be called when resources are likely to
be available
|
|