Re: [PATCH] MIPS: vmlinuz: gather some string functions into string.c

[Florian Fainelli <f.fainelli@gmail.com>]

Hello,

Le 28/09/2013 17:42, Antony Pavlov a écrit :
> This patch fixes linker error:
>
>      LD    vmlinuz
>    arch/mips/boot/compressed/decompress.o: In function `decompress_kernel':
>    decompress.c:(.text+0x754): undefined reference to `memcpy'
>    make[1]: *** [vmlinuz] Error 1
>
> Which appears when compiling vmlinuz image with CONFIG_KERNEL_LZO=y.

You would have to rebase this on top of mips-for-linux-next which 
contains a bit more ifdef for supporting LZ4 and XZ otherwise the first 
hunk of the patch does not apply.

Regarding the contents of the patch, you are somehow changing the 
existing compressor code by unconditionnaly providing a memset and 
memcpy implementation, which is fine per se but should be mentioned at 
least.

>
> Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
> ---
>   arch/mips/boot/compressed/Makefile     |  4 ++--
>   arch/mips/boot/compressed/decompress.c | 19 -------------------
>   arch/mips/boot/compressed/string.c     | 28 ++++++++++++++++++++++++++++
>   3 files changed, 30 insertions(+), 21 deletions(-)
>   create mode 100644 arch/mips/boot/compressed/string.c
>
> diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
> index 0048c08..30e30d4 100644
> --- a/arch/mips/boot/compressed/Makefile
> +++ b/arch/mips/boot/compressed/Makefile
> @@ -27,10 +27,10 @@ KBUILD_AFLAGS := $(LINUXINCLUDE) $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
>   	-DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) \
>   	-DKERNEL_ENTRY=$(VMLINUX_ENTRY_ADDRESS)
>
> -targets := head.o decompress.o dbg.o uart-16550.o uart-alchemy.o
> +targets := head.o decompress.o string.o dbg.o uart-16550.o uart-alchemy.o
>
>   # decompressor objects (linked with vmlinuz)
> -vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/dbg.o
> +vmlinuzobjs-y := $(obj)/head.o $(obj)/decompress.o $(obj)/string.o $(obj)/dbg.o
>
>   ifdef CONFIG_DEBUG_ZBOOT
>   vmlinuzobjs-$(CONFIG_SYS_SUPPORTS_ZBOOT_UART16550) += $(obj)/uart-16550.o
> diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
> index 2c95730..fc1f294 100644
> --- a/arch/mips/boot/compressed/decompress.c
> +++ b/arch/mips/boot/compressed/decompress.c
> @@ -44,29 +44,10 @@ void error(char *x)
>   #define STATIC static
>
>   #ifdef CONFIG_KERNEL_GZIP
> -void *memcpy(void *dest, const void *src, size_t n)
> -{
> -	int i;
> -	const char *s = src;
> -	char *d = dest;
> -
> -	for (i = 0; i < n; i++)
> -		d[i] = s[i];
> -	return dest;
> -}
>   #include "../../../../lib/decompress_inflate.c"
>   #endif
>
>   #ifdef CONFIG_KERNEL_BZIP2
> -void *memset(void *s, int c, size_t n)
> -{
> -	int i;
> -	char *ss = s;
> -
> -	for (i = 0; i < n; i++)
> -		ss[i] = c;
> -	return s;
> -}
>   #include "../../../../lib/decompress_bunzip2.c"
>   #endif
>
> diff --git a/arch/mips/boot/compressed/string.c b/arch/mips/boot/compressed/string.c
> new file mode 100644
> index 0000000..49e6db0
> --- /dev/null
> +++ b/arch/mips/boot/compressed/string.c
> @@ -0,0 +1,28 @@
> +/*
> + * arch/mips/boot/compressed/string.c
> + *
> + * Very small subset of simple string routines
> + */
> +
> +#include <linux/string.h>
> +
> +void *memcpy(void *dest, const void *src, size_t n)
> +{
> +	int i;
> +	const char *s = src;
> +	char *d = dest;
> +
> +	for (i = 0; i < n; i++)
> +		d[i] = s[i];
> +	return dest;
> +}
> +
> +void *memset(void *s, int c, size_t n)
> +{
> +	int i;
> +	char *ss = s;
> +
> +	for (i = 0; i < n; i++)
> +		ss[i] = c;
> +	return s;
> +}
>