Doug / smarc-fsl-linux-kernel

25 Jul, 2008

1 commit

  • 27ac792ca   PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures ... Browse Code »

    On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit
    boundary. For example:

    u64 val = PAGE_ALIGN(size);

    always returns a value < 4GB even if size is greater than 4GB.

    The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for
    example):

    #define PAGE_SHIFT 12
    #define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
    #define PAGE_MASK (~(PAGE_SIZE-1))
    ...
    #define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)

    The "~" is performed on a 32-bit value, so everything in "and" with
    PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary.
    Using the ALIGN() macro seems to be the right way, because it uses
    typeof(addr) for the mask.

    Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in
    include/linux/mm.h.

    See also lkml discussion: http://lkml.org/lkml/2008/6/11/237

    [akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c]
    [akpm@linux-foundation.org: fix v850]
    [akpm@linux-foundation.org: fix powerpc]
    [akpm@linux-foundation.org: fix arm]
    [akpm@linux-foundation.org: fix mips]
    [akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c]
    [akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c]
    [akpm@linux-foundation.org: fix powerpc]
    Signed-off-by: Andrea Righi
    Cc:
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Andrea Righi
     

09 Feb, 2008

1 commit

  • 2f569afd9   CONFIG_HIGHPTE vs. sub-page page tables. ... Browse Code »

    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

    Martin Schwidefsky
     

08 Feb, 2008

1 commit

23 Aug, 2007

2 commits

31 May, 2007

2 commits

  • 12d810c1b   m68k: discontinuous memory support ... Browse Code »

    Fix support for discontinuous memory

    Signed-off-by: Roman Zippel
    Signed-off-by: Geert Uytterhoeven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Roman Zippel
     
  • fbe9c9612   m68k: runtime patching infrastructure ... Browse Code »

    Add the basic infrastructure to allow runtime patching of kernel and modules
    to optimize a few functions with parameters, which are only calculated once
    during bootup and are otherwise constant. Use this for the conversion between
    virtual and physical addresses.

    Signed-off-by: Roman Zippel
    Signed-off-by: Geert Uytterhoeven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Roman Zippel
     

19 Sep, 2006

1 commit

26 Apr, 2006

1 commit

05 Sep, 2005

1 commit

  • fd4fd5aac   [PATCH] mm: consolidate get_order ... Browse Code »

    Someone mentioned that almost all the architectures used basically the same
    implementation of get_order. This patch consolidates them into
    asm-generic/page.h and includes that in the appropriate places. The
    exceptions are ia64 and ppc which have their own (presumably optimised)
    versions.

    Signed-off-by: Stephen Rothwell
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Stephen Rothwell
     

25 Aug, 2005

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    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!

    Linus Torvalds