linux/ipc, branch v2.6.28

sysvipc: fix the ipc structures initialization

2008-11-20T02:49:57Z

A problem was found while reviewing the code after Bugzilla bug http://bugzilla.kernel.org/show_bug.cgi?id=11796. In ipc_addid(), the newly allocated ipc structure is inserted into the ipcs tree (i.e made visible to readers) without locking it. This is not correct since its initialization continues after it has been inserted in the tree. This patch moves the ipc structure lock initialization + locking before the actual insertion. Signed-off-by: Nadia Derbey Reported-by: Clement Calmels Cc: Manfred Spraul Cc: [2.6.27.x] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] introduce fmode_t, do annotations

2008-10-21T11:47:06Z

Signed-off-by: Al Viro

message queues: increase range limits

2008-10-20T15:52:40Z

Increase the range of various posix message queue limits. Posix gives the message queue user the ability to 'trade off' the maximum size of messages with the number of possible messages that can be 'in flight'. Linux currently makes this trade off more restrictive than it needs to be. In particular, the maximum message size today can be made no smaller than 8192. This greatly restricts those applications that would like to have the ability to post large numbers of very small messages. So this task lowers the limit that the maximum message size can be set to, from 8192 to 128. It also lowers the limit that the maximum #number of messages in flight can be set to, from 10 to 1. With these changes the message queue user can make better trade offs between #messages and message size, in order to get everything to fit within the setrlimit(RLIMIT_MSGQUEUE) limit for that particular user. This patch also applies the values in /proc/sys/fs/mqueue/msg_max /proc/sys/fs/mqueue/msgsize_max as the defaults for the max #messages allowed and the max message size allowed, respectively, for those applications that do not supply these. Previously, the defaults were hardwired to 10 and 8192, respectively. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Joe Korty Cc: Al Viro Cc: Manfred Spraul Cc: Nadia Derbey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

SHM_LOCKED pages are unevictable

2008-10-20T15:50:26Z

Shmem segments locked into memory via shmctl(SHM_LOCKED) should not be kept on the normal LRU, since scanning them is a waste of time and might throw off kswapd's balancing algorithms. Place them on the unevictable LRU list instead. Use the AS_UNEVICTABLE flag to mark address_space of SHM_LOCKed shared memory regions as unevictable. Then these pages will be culled off the normal LRU lists during vmscan. Add new wrapper function to clear the mapping's unevictable state when/if shared memory segment is munlocked. Add 'scan_mapping_unevictable_page()' to mm/vmscan.c to scan all pages in the shmem segment's mapping [struct address_space] for evictability now that they're no longer locked. If so, move them to the appropriate zone lru list. Changes depend on [CONFIG_]UNEVICTABLE_LRU. [kosaki.motohiro@jp.fujitsu.com: revert shm change] Signed-off-by: Lee Schermerhorn Signed-off-by: Rik van Riel Signed-off-by: Kosaki Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc/sem.c: make free_un() static

2008-10-16T18:21:51Z

Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysctl: simplify ->strategy

2008-10-16T18:21:47Z

name and nlen parameters passed to ->strategy hook are unused, remove them. In general ->strategy hook should know what it's doing, and don't do something tricky for which, say, pointer to original userspace array may be needed (name). Signed-off-by: Alexey Dobriyan Acked-by: David S. Miller [ networking bits ] Cc: Ralf Baechle Cc: David Howells Cc: Matt Mackall Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] kill nameidata passing to permission(), rename to inode_permission()

2008-07-27T00:53:31Z

Incidentally, the name that gives hundreds of false positives on grep is not a good idea... Signed-off-by: Al Viro

SL*B: drop kmem cache argument from constructor

2008-07-26T19:00:07Z

Kmem cache passed to constructor is only needed for constructors that are themselves multiplexeres. Nobody uses this "feature", nor does anybody uses passed kmem cache in non-trivial way, so pass only pointer to object. Non-trivial places are: arch/powerpc/mm/init_64.c arch/powerpc/mm/hugetlbpage.c This is flag day, yes. Signed-off-by: Alexey Dobriyan Acked-by: Pekka Enberg Acked-by: Christoph Lameter Cc: Jon Tollefson Cc: Nick Piggin Cc: Matt Mackall [akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c] [akpm@linux-foundation.org: fix mm/slab.c] [akpm@linux-foundation.org: fix ubifs] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: do not use a negative value to re-enable msgmni automatic recomputing

2008-07-25T17:53:42Z

This patch proposes an alternative to the "magical positive-versus-negative number trick" Andrew complained about last week in http://lkml.org/lkml/2008/6/24/418. This had been introduced with the patches that scale msgmni to the amount of lowmem. With these patches, msgmni has a registered notification routine that recomputes msgmni value upon memory add/remove or ipc namespace creation/ removal. When msgmni is changed from user space (i.e. value written to the proc file), that notification routine is unregistered, and the way to make it registered back is to write a negative value into the proc file. This is the "magical positive-versus-negative number trick". To fix this, a new proc file is introduced: /proc/sys/kernel/auto_msgmni. This file acts as ON/OFF for msgmni automatic recomputing. With this patch, the process is the following: 1) kernel boots in "automatic recomputing mode" /proc/sys/kernel/msgmni contains the value that has been computed (depends on lowmem) /proc/sys/kernel/automatic_msgmni contains "1" 2) echo > /proc/sys/kernel/msgmni . sets msg_ctlmni to . de-activates automatic recomputing (i.e. if, say, some memory is added msgmni won't be recomputed anymore) . /proc/sys/kernel/automatic_msgmni now contains "0" 3) echo "0" > /proc/sys/kernel/automatic_msgmni . de-activates msgmni automatic recomputing this has the same effect as 2) except that msg_ctlmni's value stays blocked at its current value) 3) echo "1" > /proc/sys/kernel/automatic_msgmni . recomputes msgmni's value based on the current available memory size and number of ipc namespaces . re-activates automatic recomputing for msgmni. Signed-off-by: Nadia Derbey Cc: Solofo Ramangalahy Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ipc: use simple_read_from_buffer()

2008-07-25T17:53:42Z

Also this patch kills unneccesary trailing NULL character. Signed-off-by: Akinobu Mita Cc: Nadia Derbey Cc: Manfred Spraul Cc: Pierre Peiffer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds