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    SubjectRe: [PATCH] bitmap: parse input from kernel and user buffers
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    Reinette Chatre wrote:
    > lib/bitmap.c:bitmap_parse() is a library function that received as
    > input a user buffer. This seemed to have originated from the way
    > the write_proc function of the /proc filesystem operates.
    >
    > This has been reworked to not use kmalloc and eliminates a lot
    > of get_user() overhead by performing one access_ok before using
    > __get_user().
    > We need to test if we are in kernel or user space (is_user) and access
    > the buffer differently. We cannot use __get_user() to access kernel
    > addresses in all cases, for example in architectures with separate
    > address space for kernel and user.
    >
    > This function will be useful for other uses as well; for example,
    > taking input for /sysfs instead of /proc, so it was changed to accept
    > kernel buffers. We have this use for the Linux UWB project, as part
    > as the upcoming bandwidth allocator code.
    >
    > Only a few routines used this function and they were changed too.
    >
    > Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com>
    Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
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