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path: root/include/asm-s390/pgalloc.h
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2007-08-22[S390] vmur: fix diag14 exceptions with addresses > 2GB.Michael Holzheu
There are several s390 diagnose calls, which must be executed below the 2GB memory boundary. In order to enforce this, those diagnoses must be compiled into the kernel. Currently diag 14 can be called within the vmur kernel module from addresses above 2GB. This leads to specification exceptions. This patch moves diag10, diag14 and diag210 into the new diag.c file. Signed-off-by: Michael Holzheu <holzheu@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2007-02-05[S390] noexec protectionGerald Schaefer
This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-12-08[S390] Virtual memmap for s390.Heiko Carstens
Virtual memmap support for s390. Inspired by the ia64 implementation. Unlike ia64 we need a mechanism which allows us to dynamically attach shared memory regions. These memory regions are accessed via the dcss device driver. dcss implements the 'direct_access' operation, which requires struct pages for every single shared page. Therefore this implementation provides an interface to attach/detach shared memory: int add_shared_memory(unsigned long start, unsigned long size); int remove_shared_memory(unsigned long start, unsigned long size); The purpose of the add_shared_memory function is to add the given memory range to the 1:1 mapping and to make sure that the corresponding range in the vmemmap is backed with physical pages. It also initialises the new struct pages. remove_shared_memory in turn only invalidates the page table entries in the 1:1 mapping. The page tables and the memory used for struct pages in the vmemmap are currently not freed. They will be reused when the next segment will be attached. Given that the maximum size of a shared memory region is 2GB and in addition all regions must reside below 2GB this is not too much of a restriction, but there is room for improvement. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-10-04[S390] Remove open-coded mem_map usage.Heiko Carstens
Use page_to_phys and pfn_to_page to avoid open-coded mem_map usage. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2006-09-20[S390] Cleanup in page table related code.Gerald Schaefer
Changed and simplified some page table related #defines and code. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-07-12[S390] Fix sparse warnings.Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-04-26Don't include linux/config.h from anywhere else in include/David Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-03-22[PATCH] mm: remove set_pgdir leftoversChristoph Hellwig
set_pgdir isn't needed anymore for a very long time. Remove the leftover implementation on sh64 and the stub on s390. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Richard Curnow <rc@rc0.org.uk> 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!