pm24.git/include/asm-um, branch v2.6.26-rc2

rename div64_64 to div64_u64

2008-05-01T15:03:58Z

Rename div64_64 to div64_u64 to make it consistent with the other divide functions, so it clearly includes the type of the divide. Move its definition to math64.h as currently no architecture overrides the generic implementation. They can still override it of course, but the duplicated declarations are avoided. Signed-off-by: Roman Zippel Cc: Avi Kivity Cc: Russell King Cc: Geert Uytterhoeven Cc: Ralf Baechle Cc: David Howells Cc: Jeff Dike Cc: Ingo Molnar Cc: "David S. Miller" Cc: Patrick McHardy Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel: Move arches to use common unaligned access

2008-04-29T15:06:27Z

Unaligned access is ok for the following arches: cris, m68k, mn10300, powerpc, s390, x86 Arches that use the memmove implementation for native endian, and the byteshifting for the opposite endianness. h8300, m32r, xtensa Packed struct for native endian, byteshifting for other endian: alpha, blackfin, ia64, parisc, sparc, sparc64, mips, sh m86knommu is generic_be for Coldfire, otherwise unaligned access is ok. frv, arm chooses endianness based on compiler settings, uses the byteshifting versions. Remove the unaligned trap handler from frv as it is now unused. v850 is le, uses the byteshifting versions for both be and le. Remove the now unused asm-generic implementation. Signed-off-by: Harvey Harrison Acked-by: David S. Miller Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: introduce pte_special pte bit

2008-04-28T15:58:23Z

s390 for one, cannot implement VM_MIXEDMAP with pfn_valid, due to their memory model (which is more dynamic than most). Instead, they had proposed to implement it with an additional path through vm_normal_page(), using a bit in the pte to determine whether or not the page should be refcounted: vm_normal_page() { ... if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) { if (vma->vm_flags & VM_MIXEDMAP) { #ifdef s390 if (!mixedmap_refcount_pte(pte)) return NULL; #else if (!pfn_valid(pfn)) return NULL; #endif goto out; } ... } This is fine, however if we are allowed to use a bit in the pte to determine refcountedness, we can use that to _completely_ replace all the vma based schemes. So instead of adding more cases to the already complex vma-based scheme, we can have a clearly seperate and simple pte-based scheme (and get slightly better code generation in the process): vm_normal_page() { #ifdef s390 if (!mixedmap_refcount_pte(pte)) return NULL; return pte_page(pte); #else ... #endif } And finally, we may rather make this concept usable by any architecture rather than making it s390 only, so implement a new type of pte state for this. Unfortunately the old vma based code must stay, because some architectures may not be able to spare pte bits. This makes vm_normal_page a little bit more ugly than we would like, but the 2 cases are clearly seperate. So introduce a pte_special pte state, and use it in mm/memory.c. It is currently a noop for all architectures, so this doesn't actually result in any compiled code changes to mm/memory.o. BTW: I haven't put vm_normal_page() into arch code as-per an earlier suggestion. The reason is that, regardless of where vm_normal_page is actually implemented, the *abstraction* is still exactly the same. Also, while it depends on whether the architecture has pte_special or not, that is the only two possible cases, and it really isn't an arch specific function -- the role of the arch code should be to provide primitive functions and accessors with which to build the core code; pte_special does that. We do not want architectures to know or care about vm_normal_page itself, and we definitely don't want them being able to invent something new there out of sight of mm/ code. If we made vm_normal_page an arch function, then we have to make vm_insert_mixed (next patch) an arch function too. So I don't think moving it to arch code fundamentally improves any abstractions, while it does practically make the code more difficult to follow, for both mm and arch developers, and easier to misuse. [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin Acked-by: Carsten Otte Cc: Jared Hulbert Cc: Martin Schwidefsky Cc: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Generic semaphore implementation

2008-04-17T14:42:34Z

Semaphores are no longer performance-critical, so a generic C implementation is better for maintainability, debuggability and extensibility. Thanks to Peter Zijlstra for fixing the lockdep warning. Thanks to Harvey Harrison for pointing out that the unlikely() was unnecessary. Signed-off-by: Matthew Wilcox Acked-by: Ingo Molnar

uml: compile error fix

2008-04-16T02:35:40Z

This patch fixes this error: In file included from /home/wangcong/projects/linux-2.6/arch/um/kernel/smp.c:9: include2/asm/tlb.h: In function `tlb_remove_page': include2/asm/tlb.h:101: error: implicit declaration of function `page_cache_release' And since including in will break sparc, we add this #include in uml's own header. Acked-by: Jeff Dike Signed-off-by: WANG Cong Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kvm: provide kvm.h for all architecture: fixes headers_install

2008-04-02T22:28:18Z

Currently include/linux/kvm.h is not considered by make headers_install, because Kbuild cannot handle " unifdef-$(CONFIG_FOO) += foo.h. This problem was introduced by commit fb56dbb31c4738a3918db81fd24da732ce3b4ae6 Author: Avi Kivity Date: Sun Dec 2 10:50:06 2007 +0200 KVM: Export include/linux/kvm.h only if $ARCH actually supports KVM Currently, make headers_check barfs due to , which includes, not existing. Rather than add a zillion s, export kvm. only if the arch actually supports it. Signed-off-by: Avi Kivity which makes this an 2.6.25 regression. One way of solving the issue is to enhance Kbuild, but Avi and David conviced me, that changing headers_install is not the way to go. This patch changes the definition for linux/kvm.h to unifdef-y. If unifdef-y is used for linux/kvm.h "make headers_check" will fail on all architectures without asm/kvm.h. Therefore, this patch also provides asm/kvm.h on all architectures. Signed-off-by: Christian Borntraeger Acked-by: Avi Kivity Cc: Sam Ravnborg Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

uml: x86_64 should copy %fs during fork

2008-02-08T17:22:43Z

%fs needs to be copied from parent to child during fork. Tidied up some whitespace while I was here. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

uml: runtime host VMSPLIT detection

2008-02-08T17:22:42Z

Calculate TASK_SIZE at run-time by figuring out the host's VMSPLIT - this is needed on i386 if UML is to run on hosts with varying VMSPLITs without recompilation. TASK_SIZE is now defined in terms of a variable, task_size. This gets rid of an include of pgtable.h from processor.h, which can cause include loops. On i386, task_size is calculated early in boot by probing the address space in a binary search to figure out where the boundary between usable and non-usable memory is. This tries to make sure that a page that is considered to be in userspace is, or can be made, read-write. I'm concerned about a system-global VDSO page in kernel memory being hit and considered to be a userspace page. On x86_64, task_size is just the old value of CONFIG_TOP_ADDR. A bunch of config variable are gone now. CONFIG_TOP_ADDR is directly replaced by TASK_SIZE. NEST_LEVEL is gone since the relocation of the stubs makes it irrelevant. All the HOST_VMSPLIT stuff is gone. All references to these in arch/um/Makefile are also gone. I noticed and fixed a missing extern in os.h when adding os_get_task_size. Note: This has been revised to fix the 32-bit UML on 64-bit host bug that Miklos ran into. Signed-off-by: Jeff Dike Cc: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

CONFIG_HIGHPTE vs. sub-page page tables.

2008-02-08T17:22:42Z

Background: I've implemented 1K/2K page tables for s390. These sub-page page tables are required to properly support the s390 virtualization instruction with KVM. The SIE instruction requires that the page tables have 256 page table entries (pte) followed by 256 page status table entries (pgste). The pgstes are only required if the process is using the SIE instruction. The pgstes are updated by the hardware and by the hypervisor for a number of reasons, one of them is dirty and reference bit tracking. To avoid wasting memory the standard pte table allocation should return 1K/2K (31/64 bit) and 2K/4K if the process is using SIE. Problem: Page size on s390 is 4K, page table size is 1K or 2K. That means the s390 version for pte_alloc_one cannot return a pointer to a struct page. Trouble is that with the CONFIG_HIGHPTE feature on x86 pte_alloc_one cannot return a pointer to a pte either, since that would require more than 32 bit for the return value of pte_alloc_one (and the pte * would not be accessible since its not kmapped). Solution: The only solution I found to this dilemma is a new typedef: a pgtable_t. For s390 pgtable_t will be a (pte *) - to be introduced with a later patch. For everybody else it will be a (struct page *). The additional problem with the initialization of the ptl lock and the NR_PAGETABLE accounting is solved with a constructor pgtable_page_ctor and a destructor pgtable_page_dtor. The page table allocation and free functions need to call these two whenever a page table page is allocated or freed. pmd_populate will get a pgtable_t instead of a struct page pointer. To get the pgtable_t back from a pmd entry that has been installed with pmd_populate a new function pmd_pgtable is added. It replaces the pmd_page call in free_pte_range and apply_to_pte_range. Signed-off-by: Martin Schwidefsky Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

aout: suppress A.OUT library support if !CONFIG_ARCH_SUPPORTS_AOUT

2008-02-08T17:22:30Z

Suppress A.OUT library support if CONFIG_ARCH_SUPPORTS_AOUT is not set. Not all architectures support the A.OUT binfmt, so the ELF binfmt should not be permitted to go looking for A.OUT libraries to load in such a case. Not only that, but under such conditions A.OUT core dumps are not produced either. To make this work, this patch also does the following: (1) Makes the existence of the contents of linux/a.out.h contingent on CONFIG_ARCH_SUPPORTS_AOUT. (2) Renames dump_thread() to aout_dump_thread() as it's only called by A.OUT core dumping code. (3) Moves aout_dump_thread() into asm/a.out-core.h and makes it inline. This is then included only where needed. This means that this bit of arch code will be stored in the appropriate A.OUT binfmt module rather than the core kernel. (4) Drops A.OUT support for Blackfin (according to Mike Frysinger it's not needed) and FRV. This patch depends on the previous patch to move STACK_TOP[_MAX] out of asm/a.out.h and into asm/processor.h as they're required whether or not A.OUT format is available. [jdike@addtoit.com: uml: re-remove accidentally restored code] Signed-off-by: David Howells Cc: Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds