Re: [PATCH v8 6/6] powerpc/fadump: use the new parse_args callback arguments

[Hari Bathini]

In case, someone wishes for a changelog:

With fadump_rework_cmdline_params() function, parse_args() callback 
function,

taking new arguments - current & next, use them to process 
'fadump_extra_args='

parmeter, in enforcing the parameters passed through it for fadump kernel.


On Tuesday 12 September 2017 09:31 PM, Michal Suchanek wrote:
Signed-off-by: Michal Suchanek <msucha...@suse.de>
---
  arch/powerpc/kernel/fadump.c | 47 ++++++++++++--------------------------------
  1 file changed, 13 insertions(+), 34 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 8778e1cc0380..1678d99ea835 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -481,33 +481,19 @@ struct param_info {
  };

  static void __init fadump_update_params(struct param_info *param_info,
-                                       char *param, char *val)
+                                       char *param, char *val,
+                                       char *currant, char *next)
  {
-       ptrdiff_t param_offset = param - param_info->tmp_cmdline;
+       ptrdiff_t param_offset = currant - param_info->tmp_cmdline;
        size_t vallen = val ? strlen(val) : 0;
        char *tgt = param_info->cmdline + param_offset
                                - param_info->shortening;
-       int shortening = 0;
-       int quoted = 0;
+       int shortening = ((next - 1) - (currant))
+               - (FADUMP_EXTRA_ARGS_LEN + 1 + vallen);

        if (!val)
                return;

-       /* leading '"' removed from parameter */
-       if ((param > param_info->tmp_cmdline) && *(param - 1) == '"') {
-               quoted = 1;
-               shortening += 1;
-               tgt--;
-       }
-
-       /* next_arg removes one leading and one trailing '"' */
-       if ((*(tgt + FADUMP_EXTRA_ARGS_LEN + 1 + vallen + shortening) == '"') &&
-           (quoted || (*(tgt + FADUMP_EXTRA_ARGS_LEN + 1) == '"'))) {
-               shortening += 1;
-               if (!quoted)
-                       shortening += 1;
-       }
-
        /* remove one leading and one trailing quote if both are present */
        if ((val[0] == '"') && (val[vallen - 1] == '"')) {
                shortening += 2;
@@ -515,22 +501,15 @@ static void __init fadump_update_params(struct param_info 
*param_info,
                val++;
        }

-       /* some characters were removed - move the trailing part of cmdline */
-       if (shortening) {
-               char *src;
+       strncpy(tgt, FADUMP_EXTRA_ARGS_PARAM, FADUMP_EXTRA_ARGS_LEN);
+       tgt += FADUMP_EXTRA_ARGS_LEN;
+       *tgt++ = ' ';
+       strncpy(tgt, val, vallen);
+       tgt += vallen;

-               strncpy(tgt, FADUMP_EXTRA_ARGS_PARAM, FADUMP_EXTRA_ARGS_LEN);
-               tgt += FADUMP_EXTRA_ARGS_LEN;
-               *tgt++ = ' ';
-
-               strncpy(tgt, val, vallen);
-               tgt += vallen;
-
-               src = tgt + shortening;
+       if (shortening) {
+               char *src = tgt + shortening;
                memmove(tgt, src, strlen(src) + 1);
-       } else {
-               /* remove the '=' */
-               *(tgt + FADUMP_EXTRA_ARGS_LEN) = ' ';
        }

        param_info->shortening += shortening;
@@ -550,7 +529,7 @@ static int __init fadump_rework_cmdline_params(char *param, 
char *val,
                     strlen(FADUMP_EXTRA_ARGS_PARAM) - 1))
                return 0;

-       fadump_update_params(param_info, param, val);
+       fadump_update_params(param_info, param, val, currant, next);

        return 0;
  }


Thanks
Hari