generic_permission(9) centos man page | unix.com

GENERIC_PERMISSION(9)						   The Linux VFS					     GENERIC_PERMISSION(9)

NAME
       generic_permission - check for access rights on a Posix-like filesystem

SYNOPSIS
       int generic_permission(struct inode * inode, int mask);

ARGUMENTS
       inode
	   inode to check access rights for

       mask
	   right to check for (MAY_READ, MAY_WRITE, MAY_EXEC, ...)

DESCRIPTION
       Used to check for read/write/execute permissions on a file. We use "fsuid" for this, letting us set arbitrary permissions for filesystem
       access without changing the "normal" uids which are used for other things.

       generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk request cannot be satisfied (eg. requires blocking or too much
       complexity). It would then be called again in ref-walk mode.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						     GENERIC_PERMISSION(9)