lkml.org 
[lkml]   [2010]   [May]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[RFC][PATCH 6/12 not tested yet] PPC: introduce copy_in_user() for 32-bit
    During the work of KVM's dirty page logging optimization, we encountered
    the need of copy_in_user() for 32-bit ppc and x86: these will be used for
    manipulating dirty bitmaps in user space.

    So we implement copy_in_user() for 32-bit with __copy_tofrom_user().

    Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
    Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
    CC: Alexander Graf <agraf@suse.de>
    CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    CC: Paul Mackerras <paulus@samba.org>
    ---
    arch/powerpc/include/asm/uaccess.h | 17 +++++++++++++++++
    1 files changed, 17 insertions(+), 0 deletions(-)

    diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
    index bd0fb84..3a01ce8 100644
    --- a/arch/powerpc/include/asm/uaccess.h
    +++ b/arch/powerpc/include/asm/uaccess.h
    @@ -359,6 +359,23 @@ static inline unsigned long copy_to_user(void __user *to,
    return n;
    }

    +static inline unsigned long copy_in_user(void __user *to,
    + const void __user *from, unsigned long n)
    +{
    + unsigned long over;
    +
    + if (likely(access_ok(VERIFY_READ, from, n) &&
    + access_ok(VERIFY_WRITE, to, n)))
    + return __copy_tofrom_user(to, from, n);
    + if (((unsigned long)from < TASK_SIZE) ||
    + ((unsigned long)to < TASK_SIZE)) {
    + over = max((unsigned long)from, (unsigned long)to)
    + + n - TASK_SIZE;
    + return __copy_tofrom_user(to, from, n - over) + over;
    + }
    + return n;
    +}
    +
    #else /* __powerpc64__ */

    #define __copy_in_user(to, from, size) \
    --
    1.7.0.4


    \
     
     \ /
      Last update: 2010-05-04 15:07    [W:0.021 / U:90.060 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site