14 Dec, 2006

2 commits

  • Virtually index, physically tagged cache architectures can get away
    without cache flushing when forking. This patch adds a new cache
    flushing function flush_cache_dup_mm(struct mm_struct *) which for the
    moment I've implemented to do the same thing on all architectures
    except on MIPS where it's a no-op.

    Signed-off-by: Ralf Baechle
    Signed-off-by: Linus Torvalds

    Ralf Baechle
     
  • Currently, to tell a task that it should go to the refrigerator, we set the
    PF_FREEZE flag for it and send a fake signal to it. Unfortunately there
    are two SMP-related problems with this approach. First, a task running on
    another CPU may be updating its flags while the freezer attempts to set
    PF_FREEZE for it and this may leave the task's flags in an inconsistent
    state. Second, there is a potential race between freeze_process() and
    refrigerator() in which freeze_process() running on one CPU is reading a
    task's PF_FREEZE flag while refrigerator() running on another CPU has just
    set PF_FROZEN for the same task and attempts to reset PF_FREEZE for it. If
    the refrigerator wins the race, freeze_process() will state that PF_FREEZE
    hasn't been set for the task and will set it unnecessarily, so the task
    will go to the refrigerator once again after it's been thawed.

    To solve first of these problems we need to stop using PF_FREEZE to tell
    tasks that they should go to the refrigerator. Instead, we can introduce a
    special TIF_*** flag and use it for this purpose, since it is allowed to
    change the other tasks' TIF_*** flags and there are special calls for it.

    To avoid the freeze_process()-refrigerator() race we can make
    freeze_process() to always check the task's PF_FROZEN flag after it's read
    its "freeze" flag. We should also make sure that refrigerator() will
    always reset the task's "freeze" flag after it's set PF_FROZEN for it.

    Signed-off-by: Rafael J. Wysocki
    Acked-by: Pavel Machek
    Cc: Russell King
    Cc: David Howells
    Cc: Andi Kleen
    Cc: "Luck, Tony"
    Cc: Benjamin Herrenschmidt
    Cc: Paul Mackerras
    Cc: Paul Mundt
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rafael J. Wysocki
     

09 Dec, 2006

2 commits

  • In order to sort out our struct termios and add proper speed control we need
    to separate the kernel and user termios structures. Glibc is fine but the
    other libraries rely on the kernel exported struct termios and we need to
    extend this without breaking the ABI/API

    To do so we add a struct ktermios which is the kernel view of a termios
    structure and overlaps the struct termios with extra fields on the end for
    now. (That limitation will go away in later patches). Some platforms (eg
    alpha) planned ahead and thus use the same struct for both, others did not.

    This just adds the structures but does not use them, it seems a sensible
    splitting point for bisect if there are compile failures (not that I expect
    them)

    Signed-off-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     
  • This facility provides three entry points:

    ilog2() Log base 2 of unsigned long
    ilog2_u32() Log base 2 of u32
    ilog2_u64() Log base 2 of u64

    These facilities can either be used inside functions on dynamic data:

    int do_something(long q)
    {
    ...;
    y = ilog2(x)
    ...;
    }

    Or can be used to statically initialise global variables with constant values:

    unsigned n = ilog2(27);

    When performing static initialisation, the compiler will report "error:
    initializer element is not constant" if asked to take a log of zero or of
    something not reducible to a constant. They treat negative numbers as
    unsigned.

    When not dealing with a constant, they fall back to using fls() which permits
    them to use arch-specific log calculation instructions - such as BSR on
    x86/x86_64 or SCAN on FRV - if available.

    [akpm@osdl.org: MMC fix]
    Signed-off-by: David Howells
    Cc: Benjamin Herrenschmidt
    Cc: Paul Mackerras
    Cc: Herbert Xu
    Cc: David Howells
    Cc: Wojtek Kaniewski
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     

08 Dec, 2006

5 commits

  • Make the contents of the userspace asm/setup.h header consistent on all
    architectures:

    - export setup.h to userspace on all architectures
    - export only COMMAND_LINE_SIZE to userspace
    - frv: move COMMAND_LINE_SIZE from param.h
    - i386: remove duplicate COMMAND_LINE_SIZE from param.h
    - arm:
    - export ATAGs to userspace
    - change u8/u16/u32 to __u8/__u16/__u32

    Signed-off-by: Adrian Bunk
    Acked-by: Russell King
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Adrian Bunk
     
  • Pass struct dev pointer to dma_cache_sync()

    dma_cache_sync() is ill-designed in that it does not have a struct device
    pointer argument which makes proper support for systems that consist of a
    mix of coherent and non-coherent DMA devices hard. Change dma_cache_sync
    to take a struct device pointer as first argument and fix all its callers
    to pass it.

    Signed-off-by: Ralf Baechle
    Cc: James Bottomley
    Cc: "David S. Miller"
    Cc: Greg KH
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ralf Baechle
     
  • dma_is_consistent() is ill-designed in that it does not have a struct
    device pointer argument which makes proper support for systems that consist
    of a mix of coherent and non-coherent DMA devices hard. Change
    dma_is_consistent to take a struct device pointer as first argument and fix
    the sole caller to pass it.

    Signed-off-by: Ralf Baechle
    Cc: James Bottomley
    Cc: "David S. Miller"
    Cc: Greg KH
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ralf Baechle
     
  • The last thing we agreed on was to remove the macros entirely for 2.6.19,
    on all architectures. Unfortunately, I think nobody actually _did_ that,
    so they are still there.

    [akpm@osdl.org: x86_64 fix]
    Cc: David Woodhouse
    Cc: Greg Schafer
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arnd Bergmann
     
  • Introduce pagefault_{disable,enable}() and use these where previously we did
    manual preempt increments/decrements to make the pagefault handler do the
    atomic thing.

    Currently they still rely on the increased preempt count, but do not rely on
    the disabled preemption, this might go away in the future.

    (NOTE: the extra barrier() in pagefault_disable might fix some holes on
    machines which have too many registers for their own good)

    [heiko.carstens@de.ibm.com: s390 fix]
    Signed-off-by: Peter Zijlstra
    Acked-by: Nick Piggin
    Cc: Martin Schwidefsky
    Signed-off-by: Heiko Carstens
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Peter Zijlstra
     

03 Dec, 2006

1 commit


02 Dec, 2006

1 commit

  • Add arch specific dev_archdata to struct device

    Adds an arch specific struct dev_arch to struct device. This enables
    architecture to add specific fields to every device in the system, like
    DMA operation pointers, NUMA node ID, firmware specific data, etc...

    Signed-off-by: Benjamin Herrenschmidt
    Acked-by: Andi Kleen
    Acked-By: David Howells
    Signed-off-by: Greg Kroah-Hartman

    Benjamin Herrenschmidt
     

16 Oct, 2006

1 commit

  • Use inc/dec_preempt_count() rather than preempt_enable/disable() and manually
    add in the compiler barriers that were provided by the latter. This makes FRV
    consistent with other archs.

    Furthermore, the compiler barrier effects are now there unconditionally - at
    least as far as preemption is concerned - because we don't want the compiler
    moving memory accesses out of the section of code in which the mapping is in
    force - in effect the kmap_atomic() must imply a LOCK-class barrier and the
    kunmap_atomic() must imply an UNLOCK-class barrier to the compiler.

    Signed-off-by: David Howells
    Acked-by: Peter Zijlstra
    Signed-off-by: Linus Torvalds

    David Howells
     

12 Oct, 2006

1 commit

  • There's nothing arch-specific about check_signature(), so move it to
    . Use a cross between the Alpha and i386 implementations as
    the generic one.

    Signed-off-by: Matthew Wilcox
    Acked-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Matthew Wilcox
     

05 Oct, 2006

1 commit

  • Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
    of passing regs around manually through all ~1800 interrupt handlers in the
    Linux kernel.

    The regs pointer is used in few places, but it potentially costs both stack
    space and code to pass it around. On the FRV arch, removing the regs parameter
    from all the genirq function results in a 20% speed up of the IRQ exit path
    (ie: from leaving timer_interrupt() to leaving do_IRQ()).

    Where appropriate, an arch may override the generic storage facility and do
    something different with the variable. On FRV, for instance, the address is
    maintained in GR28 at all times inside the kernel as part of general exception
    handling.

    Having looked over the code, it appears that the parameter may be handed down
    through up to twenty or so layers of functions. Consider a USB character
    device attached to a USB hub, attached to a USB controller that posts its
    interrupts through a cascaded auxiliary interrupt controller. A character
    device driver may want to pass regs to the sysrq handler through the input
    layer which adds another few layers of parameter passing.

    I've build this code with allyesconfig for x86_64 and i386. I've runtested the
    main part of the code on FRV and i386, though I can't test most of the drivers.
    I've also done partial conversion for powerpc and MIPS - these at least compile
    with minimal configurations.

    This will affect all archs. Mostly the changes should be relatively easy.
    Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

    struct pt_regs *old_regs = set_irq_regs(regs);

    And put the old one back at the end:

    set_irq_regs(old_regs);

    Don't pass regs through to generic_handle_irq() or __do_IRQ().

    In timer_interrupt(), this sort of change will be necessary:

    - update_process_times(user_mode(regs));
    - profile_tick(CPU_PROFILING, regs);
    + update_process_times(user_mode(get_irq_regs()));
    + profile_tick(CPU_PROFILING);

    I'd like to move update_process_times()'s use of get_irq_regs() into itself,
    except that i386, alone of the archs, uses something other than user_mode().

    Some notes on the interrupt handling in the drivers:

    (*) input_dev() is now gone entirely. The regs pointer is no longer stored in
    the input_dev struct.

    (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
    something different depending on whether it's been supplied with a regs
    pointer or not.

    (*) Various IRQ handler function pointers have been moved to type
    irq_handler_t.

    Signed-Off-By: David Howells
    (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

    David Howells
     

04 Oct, 2006

1 commit


02 Oct, 2006

1 commit

  • The last in-kernel user of errno is gone, so we should remove the definition
    and everything referring to it. This also removes the now-unused lib/execve.c
    file that was introduced earlier.

    Also remove every trace of __KERNEL_SYSCALLS__ that still remained in the
    kernel.

    Signed-off-by: Arnd Bergmann
    Cc: Andi Kleen
    Cc: Paul Mackerras
    Cc: Benjamin Herrenschmidt
    Cc: Richard Henderson
    Cc: Ivan Kokshaysky
    Cc: Russell King
    Cc: Ian Molton
    Cc: Mikael Starvik
    Cc: David Howells
    Cc: Yoshinori Sato
    Cc: Hirokazu Takata
    Cc: Ralf Baechle
    Cc: Kyle McMartin
    Cc: Heiko Carstens
    Cc: Martin Schwidefsky
    Cc: Paul Mundt
    Cc: Kazumoto Kojima
    Cc: Richard Curnow
    Cc: William Lee Irwin III
    Cc: "David S. Miller"
    Cc: Jeff Dike
    Cc: Paolo 'Blaisorblade' Giarrusso
    Cc: Miles Bader
    Cc: Chris Zankel
    Cc: "Luck, Tony"
    Cc: Geert Uytterhoeven
    Cc: Roman Zippel
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arnd Bergmann
     

01 Oct, 2006

2 commits

  • Now that ptep_establish has a definition in PAE i386 3-level paging code, the
    only paging model which is insane enough to have multi-word hardware PTEs
    which are not efficient to set atomically, we can remove the ghost of
    set_pte_atomic from other architectures which falesly duplicated it, and
    remove all knowledge of it from the generic pgtable code.

    set_pte_atomic is now a private pte operator which is specific to i386

    Signed-off-by: Zachary Amsden
    Cc: Rusty Russell
    Cc: Jeremy Fitzhardinge
    Cc: Andi Kleen
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Zachary Amsden
     
  • Remove a few unused defines and remove obsolete information from comments.

    Signed-off-by: Roman Zippel
    Cc: john stultz
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Roman Zippel
     

27 Sep, 2006

1 commit


26 Sep, 2006

6 commits

  • Optimise ffs(x) by using fls(x & x - 1) which we optimise to use the SCAN
    instruction.

    Signed-off-by: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Implement fls64() for FRV without recource to conditional jumps.

    Signed-off-by: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Fix FRV fls() to handle bit 31 being set correctly (it should return 32 not 0).

    Signed-off-by: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • Make the FRV arch use the generic IRQ code rather than having its own
    routines for doing so.

    Signed-off-by: David Howells
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    David Howells
     
  • One of the changes necessary for shared page tables is to standardize the
    pxx_page macros. pte_page and pmd_page have always returned the struct
    page associated with their entry, while pte_page_kernel and pmd_page_kernel
    have returned the kernel virtual address. pud_page and pgd_page, on the
    other hand, return the kernel virtual address.

    Shared page tables needs pud_page and pgd_page to return the actual page
    structures. There are very few actual users of these functions, so it is
    simple to standardize their usage.

    Since this is basic cleanup, I am submitting these changes as a standalone
    patch. Per Hugh Dickins' comments about it, I am also changing the
    pxx_page_kernel macros to pxx_page_vaddr to clarify their meaning.

    Signed-off-by: Dave McCracken
    Cc: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Dave McCracken
     
  • They all contain the same thing. Instead, have a single generic one in
    include/asm-generic, and permit an arch to override as needed.

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     

25 Sep, 2006

1 commit


15 Jul, 2006

1 commit

  • set_wmb should not be used in the kernel because it just confuses the
    code more and has no benefit. Since it is not currently used in the
    kernel this patch removes it so that new code does not include it.

    All archs define set_wmb(var, value) to do { var = value; wmb(); }
    while(0) except ia64 and sparc which use a mb() instead. But this is
    still moot since it is not used anyway.

    Hasn't been tested on any archs but x86 and x86_64 (and only compiled
    tested)

    Signed-off-by: Steven Rostedt
    Signed-off-by: Linus Torvalds

    Steven Rostedt
     

13 Jul, 2006

1 commit

  • During the recent discussion of taking 'volatile' off of the spinlock, I
    noticed that while most arches #define cpu_relax() such that it implies
    barrier(), some arches define cpu_relax() to be empty.

    This patch changes the definition of cpu_relax() for frv, h8300, m68knommu,
    sh, sh64, v850 and xtensa from an empty while(0) to the compiler barrier().

    Signed-off-by: Chase Venters
    Acked-by: Arjan van de Ven
    Signed-off-by: Linus Torvalds

    Chase Venters
     

11 Jul, 2006

2 commits


05 Jul, 2006

1 commit

  • * git://git.infradead.org/hdrinstall-2.6:
    Remove export of include/linux/isdn/tpam.h
    Remove and from userspace export
    Restrict headers exported to userspace for SPARC and SPARC64
    Add empty Kbuild files for 'make headers_install' in remaining arches.
    Add Kbuild file for Alpha 'make headers_install'
    Add Kbuild file for SPARC 'make headers_install'
    Add Kbuild file for IA64 'make headers_install'
    Add Kbuild file for S390 'make headers_install'
    Add Kbuild file for i386 'make headers_install'
    Add Kbuild file for x86_64 'make headers_install'
    Add Kbuild file for PowerPC 'make headers_install'
    Add generic Kbuild files for 'make headers_install'
    Basic implementation of 'make headers_check'
    Basic implementation of 'make headers_install'

    Linus Torvalds
     

03 Jul, 2006

1 commit


30 Jun, 2006

1 commit

  • This patch implements an API whereby an application can determine the
    label of its peer's Unix datagram sockets via the auxiliary data mechanism of
    recvmsg.

    Patch purpose:

    This patch enables a security-aware application to retrieve the
    security context of the peer of a Unix datagram socket. The application
    can then use this security context to determine the security context for
    processing on behalf of the peer who sent the packet.

    Patch design and implementation:

    The design and implementation is very similar to the UDP case for INET
    sockets. Basically we build upon the existing Unix domain socket API for
    retrieving user credentials. Linux offers the API for obtaining user
    credentials via ancillary messages (i.e., out of band/control messages
    that are bundled together with a normal message). To retrieve the security
    context, the application first indicates to the kernel such desire by
    setting the SO_PASSSEC option via getsockopt. Then the application
    retrieves the security context using the auxiliary data mechanism.

    An example server application for Unix datagram socket should look like this:

    toggle = 1;
    toggle_len = sizeof(toggle);

    setsockopt(sockfd, SOL_SOCKET, SO_PASSSEC, &toggle, &toggle_len);
    recvmsg(sockfd, &msg_hdr, 0);
    if (msg_hdr.msg_controllen > sizeof(struct cmsghdr)) {
    cmsg_hdr = CMSG_FIRSTHDR(&msg_hdr);
    if (cmsg_hdr->cmsg_len cmsg_level == SOL_SOCKET &&
    cmsg_hdr->cmsg_type == SCM_SECURITY) {
    memcpy(&scontext, CMSG_DATA(cmsg_hdr), sizeof(scontext));
    }
    }

    sock_setsockopt is enhanced with a new socket option SOCK_PASSSEC to allow
    a server socket to receive security context of the peer.

    Testing:

    We have tested the patch by setting up Unix datagram client and server
    applications. We verified that the server can retrieve the security context
    using the auxiliary data mechanism of recvmsg.

    Signed-off-by: Catherine Zhang
    Acked-by: Acked-by: James Morris
    Signed-off-by: David S. Miller

    Catherine Zhang
     

23 Jun, 2006

7 commits