summaryrefslogtreecommitdiff
path: root/include/linux/shm.h
AgeCommit message (Collapse)Author
2011-07-30shm: handle separate PID namespaces caseVasiliy Kulikov
shm_try_destroy_orphaned() and shm_try_destroy_current() didn't handle the case of separate PID namespaces, but a single IPC namespace. If there are tasks with the same PID values using the same shmem object, the wrong destroy decision could be reached. On shm segment creation store the pointer to the creator task in shmid_kernel->shm_creator field and zero it on task exit. Then use the ->shm_creator insread of shm_cprid in both functions. As shmid_kernel object is already locked at this stage, no additional locking is needed. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26ipc: introduce shm_rmid_forced sysctlVasiliy Kulikov
Add support for the shm_rmid_forced sysctl. If set to 1, all shared memory objects in current ipc namespace will be automatically forced to use IPC_RMID. The POSIX way of handling shmem allows one to create shm objects and call shmdt(), leaving shm object associated with no process, thus consuming memory not counted via rlimits. With shm_rmid_forced=1 the shared memory object is counted at least for one process, so OOM killer may effectively kill the fat process holding the shared memory. It obviously breaks POSIX - some programs relying on the feature would stop working. So set shm_rmid_forced=1 only if you're sure nobody uses "orphaned" memory. Use shm_rmid_forced=0 by default for compatability reasons. The feature was previously impemented in -ow as a configure option. [akpm@linux-foundation.org: fix documentation, per Randy] [akpm@linux-foundation.org: fix warning] [akpm@linux-foundation.org: readability/conventionality tweaks] [akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout] Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Solar Designer <solar@openwall.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07Unexport asm/page.hKirill A. Shutemov
Do not export asm/page.h during make headers_install. This removes PAGE_SIZE from userspace headers. Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com> Reviewed-by: David Woodhouse <dwmw2@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19ipc: store ipcs into IDRsNadia Derbey
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 <Nadia.Derbey@bull.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17unexport asm/shmparam.hOlaf Hering
SHMLBA cant possible be used in userspace, see sparc versions of that header. Do not export asm/shmparam.h during make headers_install_all This removes another uservisible place of PAGE_SIZE Signed-off-by: Olaf Hering <olaf@aepfle.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-01[PATCH] Fix get_unmapped_area and fsync for hugetlb shm segmentsAdam Litke
This patch provides the following hugetlb-related fixes to the recent stacked shm files changes: - Update is_file_hugepages() so it will reconize hugetlb shm segments. - get_unmapped_area must be called with the nested file struct to handle the sfd->file->f_ops->get_unmapped_area == NULL case. - The fsync f_op must be wrapped since it is specified in the hugetlbfs f_ops. This is based on proposed fixes from Eric Biederman that were debugged and tested by me. Without it, attempting to use hugetlb shared memory segments on powerpc (and likely ia64) will kill your box. Signed-off-by: Adam Litke <agl@us.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Andrew Morton <akpm@linux-foundation.org> Acked-by: William Irwin <bill.irwin@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2005-11-07[PATCH] SHM_NORESERVE flags for shmget()Badari Pulavarty
Add SHM_NORESERVE functionality similar to MAP_NORESERVE for shared memory segments. This is mainly to avoid abuse of OVERCOMMIT_ALWAYS and this flag is ignored for OVERCOMMIT_NEVER. Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!