[PATCH] kexec-zImage-arm: simply cmdline-related DTB resizing

[Daniel Mack]

On 12/20/2012 07:19 AM, Stephen Warren wrote:
> From: Stephen Warren <swarren at nvidia.com>
> 
> When resizing a dtb to add the command-line, only resize the DTB once,
> rather than once to add the /chosen node, and once to add the bootargs
> property.
> 
> Also, simply add 1K of overhead (beyond strlen(cmdline)) to the buffer,
> to avoid requiring precise knowledge of the size impact of the requested
> FTB changes. In particular, some padding is performed when setting
> property values, which was not accounted for in the current code, which
> caused failures to set the bootargs values in some cases.
> 
> Cc: Daniel Mack <zonque at gmail.com>
> Signed-off-by: Stephen Warren <swarren at nvidia.com>

Much cleaner, thanks Stephen.


Daniel


> ---
>  kexec/arch/arm/kexec-zImage-arm.c |   21 ++++++---------------
>  1 file changed, 6 insertions(+), 15 deletions(-)
> 
> diff --git a/kexec/arch/arm/kexec-zImage-arm.c b/kexec/arch/arm/kexec-zImage-arm.c
> index 0950897..db29a7b 100644
> --- a/kexec/arch/arm/kexec-zImage-arm.c
> +++ b/kexec/arch/arm/kexec-zImage-arm.c
> @@ -370,31 +370,22 @@ int zImage_arm_load(int argc, char **argv, const char *buf, off_t len,
>  				const char *prop_name = "bootargs";
>  				int off;
>  
> +				dtb_length = fdt_totalsize(dtb_buf) + 1024 +
> +					strlen(command_line);
> +				dtb_buf = xrealloc(dtb_buf, dtb_length);
> +				fdt_set_totalsize(dtb_buf, dtb_length);
> +
>  				/* check if a /choosen subnode already exists */
>  				off = fdt_path_offset(dtb_buf, node_name);
>  
> -				if (off == -FDT_ERR_NOTFOUND) {
> -					dtb_length = fdt_totalsize(dtb_buf)
> -							+ strlen(node_name) + 1
> -							+ sizeof(struct fdt_node_header)
> -							+ FDT_TAGSIZE;
> -					dtb_buf = xrealloc(dtb_buf, dtb_length);
> -					fdt_set_totalsize(dtb_buf, dtb_length);
> +				if (off == -FDT_ERR_NOTFOUND)
>  					off = fdt_add_subnode(dtb_buf, off, node_name);
> -				}
>  
>  				if (off < 0) {
>  					fprintf(stderr, "FDT: Error adding %s node.\n", node_name);
>  					return -1;
>  				}
>  
> -				dtb_length = fdt_totalsize(dtb_buf)
> -						+ strlen(prop_name)
> -						+ strlen(command_line) + 1
> -						+ sizeof(struct fdt_property);
> -				dtb_buf = xrealloc(dtb_buf, dtb_length);
> -				fdt_set_totalsize(dtb_buf, dtb_length);
> -
>  				if (fdt_setprop(dtb_buf, off, prop_name,
>  						command_line, strlen(command_line) + 1) != 0) {
>  					fprintf(stderr, "FDT: Error setting %s/%s property.\n",
>