generic_permission (9) - Linux Man Pages
generic_permission: check for access rights on a Posix-like filesystem
generic_permission - check for access rights on a Posix-like filesystem
int generic_permission(struct inode
*inode, int mask);
- inode to check access rights for
- right to check for (MAY_READ, MAY_WRITE, MAY_EXEC, ...)
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.