Announces intention to map a file.
|vp||Points to the vnode to be queried.|
|offset||Specifies the starting offset for the map request.|
|length||Specifies the length of the mapping request.|
|mflags||Specifies the mapping flags.|
|fflags||Specifies the file flags.|
|crp||Specifies user's credentials.|
The vn_map_lloff entry point is used to tell the file system that the file is going to be accessed by memory mapped loads and stores. The file system should fail the request if it does not support memory mapping. This interface allows applications to specify starting offsets that are larger than 2 gigabytes.
File systems that do not define GFS_VERSION421 in their gfs flags do not need to supply a vn_map_lloff entry point.
The vn_map_lloff entry point can be called from the process environment only.
|Zero||Indicates a successful operation.|
|Nonzero||Indicates that the operation failed; return values should be chosen from the /usr/include/sys/errno.h file.|
The shmat and mmap subroutines.
Virtual File System Overview, Logical File System Overview, Understanding Virtual Nodes (V-nodes), and Virtual File System Kernel Extensions Overview.
List of Virtual File System Operations.