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    SubjectRe: common RODATA in vmlinux.lds.h (2.5.59)
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    Yeah, the new generic RODATA stuff is way broken on the v850 too.

    Besides the over-eager use of sections, it also assumes that C symbol
    names map one-to-one with `linker symbol' names, which isn't true with
    the default v850 compiler.

    Here's my local rewrite of include/asm-generic/vmlinux.lds.h, which
    works on the v850, and seems like it should be usable by other systems
    as well.

    It does two things:

    (1) Separates the RODATA stuff into two macros, an input-sections-and-
    symbols macro, RODATA_CONTENTS, which can be put into any
    appropriate section, and a RODATA_SECTION macro, which simply
    defines an appropriate section using that. I guess most archs
    could just use RODATA_SECTION in the same way they use `RODATA'
    now, but the v850 uses RODATA_CONTENTS instead.

    This assumes that the original division into lots of little
    output sections was gratuitous, and that putting everything into
    a single section is OK.

    [You might notice that this follows the macro scheme already used
    by the v850's vmlinux.lds.S file]

    (2) Adds a `CSYM' macro which is used for every symbol name that is
    exported to C. By default this just expands to its argument, but
    an arch may define `C_SYMBOL_PREFIX' in order to add a prefix to
    all C symbols.

    What do you think of this?

    [To be honest, I think the stuff with `LOAD_OFFSET' is a bit of a waste;
    it seems cleaner to just have archs define their own sections as
    appropriate, and use RODATA_CONTENTS directly -- it's the input sections
    and related symbols that are always changing (and so better centralized),
    after all, not the output sections.]

    Thanks,

    -Miles


    Here's my rewrite of include/asm-generic/vmlinux.lds.h:


    #ifndef LOAD_OFFSET
    #define LOAD_OFFSET 0
    #endif

    #ifndef C_SYMBOL_PREFIX
    #define C_SYMBOL_PREFIX
    #endif

    #define __paste(x,y) x##y
    #define _paste(x,y) __paste(x,y)
    #define CSYM(name) _paste(C_SYMBOL_PREFIX,name)

    /* Section contents for read-only data. */
    #define RODATA_CONTENTS \
    *(.rodata) *(.rodata.*) \
    *(__vermagic) /* Kernel version magic */ \
    *(.rodata1) \
    /* Kernel symbol table: Normal symbols */ \
    CSYM(__start___ksymtab) = .; \
    *(__ksymtab) \
    CSYM(__stop___ksymtab) = .; \
    /* Kernel symbol table: GPL-only symbols */ \
    CSYM(__start___gpl_ksymtab) = .; \
    *(__gpl_ksymtab) \
    CSYM(__stop___gpl_ksymtab) = .; \
    /* Kernel symbol table: strings */ \
    *(__ksymtab_strings)

    /* A standalone section containing RODATA_CONTENTS. */
    #define RODATA_SECTION \
    .rodata : AT(ADDR(.rodata) - LOAD_OFFSET) { \
    RODATA_CONTENTS \
    }



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