user/sven/linux.git/ipc/util.h, branch v2.6.33.6

ipc: unbreak 32-bit shmctl/semctl/msgctl

2009-06-21T19:48:43Z

31a985f "ipc: use __ARCH_WANT_IPC_PARSE_VERSION in ipc/util.h" would choose the implementation of ipc_parse_version() based on a symbol defined in . But it failed to also include this header and thus broke IPC_64-passing 32-bit userspace because the flag wasn't masked out properly anymore and the command not understood. Include to give the architecture a chance to ask for the no-no-op ipc_parse_version(). Signed-off-by: Johannes Weiner Acked-by: Arnd Bergmann Signed-off-by: Linus Torvalds

ipcns: move free_ipcs() proto

2009-06-18T20:03:56Z

Function is really private to ipc/ and avoid struct kern_ipc_perm forward declaration. Signed-off-by: Alexey Dobriyan Reviewed-by: WANG Cong Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: use __ARCH_WANT_IPC_PARSE_VERSION in ipc/util.h

2009-06-18T20:03:54Z

The definition of ipc_parse_version depends on __ARCH_WANT_IPC_PARSE_VERSION, but the header file declares it conditionally based on the architecture. Use the macro consistently to make it easier to add new architectures. Signed-off-by: Arnd Bergmann Acked-by: Serge Hallyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

namespaces: ipc namespaces: implement support for posix msqueues

2009-04-07T15:31:09Z

Implement multiple mounts of the mqueue file system, and link it to usage of CLONE_NEWIPC. Each ipc ns has a corresponding mqueuefs superblock. When a user does clone(CLONE_NEWIPC) or unshare(CLONE_NEWIPC), the unshare will cause an internal mount of a new mqueuefs sb linked to the new ipc ns. When a user does 'mount -t mqueue mqueue /dev/mqueue', he mounts the mqueuefs superblock. Posix message queues can be worked with both through the mq_* system calls (see mq_overview(7)), and through the VFS through the mqueue mount. Any usage of mq_open() and friends will work with the acting task's ipc namespace. Any actions through the VFS will work with the mqueuefs in which the file was created. So if a user doesn't remount mqueuefs after unshare(CLONE_NEWIPC), mq_open("/ab") will not be reflected in "ls /dev/mqueue". If task a mounts mqueue for ipc_ns:1, then clones task b with a new ipcns, ipcns:2, and then task a is the last task in ipc_ns:1 to exit, then (1) ipc_ns:1 will be freed, (2) it's superblock will live on until task b umounts the corresponding mqueuefs, and vfs actions will continue to succeed, but (3) sb->s_fs_info will be NULL for the sb corresponding to the deceased ipc_ns:1. To make this happen, we must protect the ipc reference count when a) a task exits and drops its ipcns->count, since it might be dropping it to 0 and freeing the ipcns b) a task accesses the ipcns through its mqueuefs interface, since it bumps the ipcns refcount and might race with the last task in the ipcns exiting. So the kref is changed to an atomic_t so we can use atomic_dec_and_lock(&ns->count,mq_lock), and every access to the ipcns through ns = mqueuefs_sb->s_fs_info is protected by the same lock. Signed-off-by: Cedric Le Goater Signed-off-by: Serge E. Hallyn Cc: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

namespaces: mqueue ns: move mqueue_mnt into struct ipc_namespace

2009-04-07T15:31:09Z

Move mqueue vfsmount plus a few tunables into the ipc_namespace struct. The CONFIG_IPC_NS boolean and the ipc_namespace struct will serve both the posix message queue namespaces and the SYSV ipc namespaces. The sysctl code will be fixed separately in patch 3. After just this patch, making a change to posix mqueue tunables always changes the values in the initial ipc namespace. Signed-off-by: Cedric Le Goater Signed-off-by: Serge E. Hallyn Cc: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: get rid of ipc_lock_down()

2008-07-25T17:53:42Z

Remove the ipc_lock_down() routines: they used to call idr_find() locklessly (given that the ipc ids lock was already held), so they are not needed anymore. Signed-off-by: Nadia Derbey Acked-by: "Paul E. McKenney" Cc: Manfred Spraul Cc: Jim Houston Cc: Pierre Peiffer Acked-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: add definitions of USHORT_MAX and others

2008-04-29T15:06:14Z

Add definitions of USHORT_MAX and others into kernel. ipc uses it and slub implementation might also use it. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Zhang Yanmin Reviewed-by: Christoph Lameter Cc: Nadia Derbey Cc: "Pierre Peiffer" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

IPC: consolidate all xxxctl_down() functions

2008-04-29T15:06:14Z

semctl_down(), msgctl_down() and shmctl_down() are used to handle the same set of commands for each kind of IPC. They all start to do the same job (they retrieve the ipc and do some permission checks) before handling the commands on their own. This patch proposes to consolidate this by moving these same pieces of code into one common function called ipcctl_pre_down(). It simplifies a little these xxxctl_down() functions and increases a little the maintainability. Signed-off-by: Pierre Peiffer Acked-by: Serge Hallyn Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

IPC: introduce ipc_update_perm()

2008-04-29T15:06:13Z

The IPC_SET command performs the same permission setting for all IPCs. This patch introduces a common ipc_update_perm() function to update these permissions and makes use of it for all IPCs. Signed-off-by: Pierre Peiffer Acked-by: Serge Hallyn Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: recompute msgmni on memory add / remove

2008-04-29T15:06:12Z

Introduce the registration of a callback routine that recomputes msg_ctlmni upon memory add / remove. A single notifier block is registered in the hotplug memory chain for all the ipc namespaces. Since the ipc namespaces are not linked together, they have their own notification chain: one notifier_block is defined per ipc namespace. Each time an ipc namespace is created (removed) it registers (unregisters) its notifier block in (from) the ipcns chain. The callback routine registered in the memory chain invokes the ipcns notifier chain with the IPCNS_LOWMEM event. Each callback routine registered in the ipcns namespace, in turn, recomputes msgmni for the owning namespace. Signed-off-by: Nadia Derbey Cc: Yasunori Goto Cc: Matt Helsley Cc: Mingming Cao Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds