IPCCTL_PRE_DOWN(9) Kernel IPC facilities IPCCTL_PRE_DOWN(9)NAME
ipcctl_pre_down - retrieve an ipc and check permissions for some
IPC_XXX cmd
SYNOPSIS
struct kern_ipc_perm * ipcctl_pre_down(struct ipc_ids * ids, int id,
int cmd,
struct ipc64_perm * perm,
int extra_perm);
ARGUMENTS
ids
the table of ids where to look for the ipc
id
the id of the ipc to retrieve
cmd
the cmd to check
perm
the permission to set
extra_perm
one extra permission parameter used by msq
DESCRIPTION
This function does some common audit and permissions check for some
IPC_XXX cmd and is called from semctl_down, shmctl_down and
msgctl_down. It must be called without any lock held and - retrieves
the ipc with the given id in the given table. - performs some audit and
permission check, depending on the given cmd - returns the ipc with
both ipc and rw_mutex locks held in case of success or an err-code
without any lock held otherwise.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 IPCCTL_PRE_DOWN(9)