linux/ipc/msg.c, branch v2.6.24

IPC: fix error case when idr-cache is empty in ipcget()

2007-10-19T18:53:49Z

With the use of idr to store the ipc, the case where the idr cache is empty, when idr_get_new is called (this may happen even if we call idr_pre_get() before), is not well handled: it lets semget()/shmget()/msgget() return ENOSPC when this cache is empty, what 1. does not reflect the facts and 2. does not conform to the man(s). This patch fixes this by retrying the whole process of allocation in this case. Signed-off-by: Pierre Peiffer Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

virtualization of sysv msg queues is incomplete

2007-10-19T18:53:48Z

Virtualization of sysv msg queues is incomplete: msg_hdrs and msg_bytes variables visible from userspace are global. Let's make them per-namespace. Signed-off-by: Alexey Kuznetsov Signed-off-by: Kirill Korotaev Cc: Pierre Peiffer Cc: Nadia Derbey Cc: Serge Hallyn Acked-by: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: remove unneeded parameters

2007-10-19T18:53:48Z

Remvoe the unneeded parameters from ipc_checkid() and ipc_buildid() interfaces. Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

fix idr_find() locking

2007-10-19T18:53:48Z

This is a patch that fixes the way idr_find() used to be called in ipc_lock(): in all the paths that don't imply an update of the ipcs idr, it was called without the idr tree being locked. The changes are: . in ipc_ids, the mutex has been changed into a reader/writer semaphore. . ipc_lock() now takes the mutex as a reader during the idr_find(). . a new routine ipc_lock_down() has been defined: it doesn't take the mutex, assuming that it is being held by the caller. This is the routine that is now called in all the update paths. Signed-off-by: Nadia Derbey Acked-by: Jarek Poplawski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: fix wrong comments

2007-10-19T18:53:47Z

This patch fixes the wrong / obsolete comments in the ipc code. Also adds a missing lock around ipc_get_maxid() in shm_get_stat(). Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Storing ipcs into IDRs

2007-10-19T18:53:46Z

This patch converts casts of struct kern_ipc_perm to . struct msg_queue . struct sem_array . struct shmid_kernel into the equivalent container_of() macro. It improves code maintenance because the code need not change if kern_ipc_perm is no longer at the beginning of the containing struct. Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: integrate ipc_checkid() into ipc_lock()

2007-10-19T18:53:44Z

This patch introduces a new ipc_lock_check() routine interface: . each time ipc_checkid() is called, this is done after calling ipc_lock(). ipc_checkid() is now called from inside ipc_lock_check(). [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix RCU locking] Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: unify the syscalls code

2007-10-19T18:53:44Z

This patch introduces a change into the sys_msgget(), sys_semget() and sys_shmget() routines: they now share a common code, which is better for maintainability. Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: store ipcs into IDRs

2007-10-19T18:53:44Z

This patch introduces ipcs storage into IDRs. The main changes are: . This ipc_ids structure is changed: the entries array is changed into a root idr structure. . The grow_ary() routine is removed: it is not needed anymore when adding an ipc structure, since we are now using the IDR facility. . The ipc_rmid() routine interface is changed: . there is no need for this routine to return the pointer passed in as argument: it is now declared as a void . since the id is now part of the kern_ipc_perm structure, no need to have it as an argument to the routine Signed-off-by: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pid namespaces: changes to show virtual ids to user

2007-10-19T18:53:40Z

This is the largest patch in the set. Make all (I hope) the places where the pid is shown to or get from user operate on the virtual pids. The idea is: - all in-kernel data structures must store either struct pid itself or the pid's global nr, obtained with pid_nr() call; - when seeking the task from kernel code with the stored id one should use find_task_by_pid() call that works with global pids; - when showing pid's numerical value to the user the virtual one should be used, but however when one shows task's pid outside this task's namespace the global one is to be used; - when getting the pid from userspace one need to consider this as the virtual one and use appropriate task/pid-searching functions. [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: nuther build fix] [akpm@linux-foundation.org: yet nuther build fix] [akpm@linux-foundation.org: remove unneeded casts] Signed-off-by: Pavel Emelyanov Signed-off-by: Alexey Dobriyan Cc: Sukadev Bhattiprolu Cc: Oleg Nesterov Cc: Paul Menage Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds