vnop_unmap Entry Point
Purpose
Unmaps a file.
Syntax
Description
The vnop_unmap entry point is called by the logical file system to unmap a file. When this entry point routine completes successfully, the use count for the memory object should be decremented and (if the use count went to 0) the memory object should be destroyed. The file system implementation is required to perform only those operations that are unique to the file system. The logical file system handles virtual-memory management operations.
Parameters
| Item | Description |
|---|---|
| vp | Points to the v-node (virtual node) of the file. |
| flag | Indicates
how the file was mapped. This flag takes the following
values:
|
| crp | Points to the cred structure. This structure contains data that the file system can use to validate access permission. |
Execution Environment
The vnop_unmap entry point can be called from the process environment only.
Return Values
| Item | Description |
|---|---|
| 0 | Indicates success. |
Nonzero return values are returned from the /usr/include/sys/errno.h file to indicate failure.