lib: Add a generic cmdline parse function parse_option_str

There should be a generic function to parse params like a=b,c
Adding parse_option_str in lib/cmdline.c which will return true
if there's specified option set in the params.

Also updated efi=old_map parsing code to use the new function

Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index c90d3cd2728ce17cb7f1f98407ee43bb69c1b50a..c73a7df5d37f174d32401794363740c97f389e51 100644 (file)
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -932,26 +932,8 @@ u64 efi_mem_attributes(unsigned long phys_addr)
 
 static int __init parse_efi_cmdline(char *str)
 {
-       if (*str == '=')
-               str++;
-
-       while (*str) {
-               if (!strncmp(str, "old_map", 7)) {
-                       set_bit(EFI_OLD_MEMMAP, &efi.flags);
-                       str += strlen("old_map");
-               }
-
-               /*
-                * Skip any options we don't understand. Presumably
-                * they apply to the EFI boot stub.
-                */
-               while (*str && *str != ',')
-                       str++;
-
-               /* If we hit a delimiter, skip it */
-               if (*str == ',')
-                       str++;
-       }
+       if (parse_option_str(str, "old_map"))
+               set_bit(EFI_OLD_MEMMAP, &efi.flags);
 
        return 0;
 }

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 95624bed87ef6f8c389e78621b628240bf408208..f66427ef0628caaf433f5b3f17a6644d599938c3 100644 (file)
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -407,6 +407,7 @@ int vsscanf(const char *, const char *, va_list);
 extern int get_option(char **str, int *pint);
 extern char *get_options(const char *str, int nints, int *ints);
 extern unsigned long long memparse(const char *ptr, char **retptr);
+extern bool parse_option_str(const char *str, const char *option);
 
 extern int core_kernel_text(unsigned long addr);
 extern int core_kernel_data(unsigned long addr);

diff --git a/lib/cmdline.c b/lib/cmdline.c
index 76a712e6e20e3d0480d9f338565079a9089560dd..8f13cf73c2ecf916c203ef7e963d250a113c3dee 100644 (file)
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -160,3 +160,32 @@ unsigned long long memparse(const char *ptr, char **retptr)
        return ret;
 }
 EXPORT_SYMBOL(memparse);
+
+/**
+ *     parse_option_str - Parse a string and check an option is set or not
+ *     @str: String to be parsed
+ *     @option: option name
+ *
+ *     This function parses a string containing a comma-separated list of
+ *     strings like a=b,c.
+ *
+ *     Return true if there's such option in the string, or return false.
+ */
+bool parse_option_str(const char *str, const char *option)
+{
+       while (*str) {
+               if (!strncmp(str, option, strlen(option))) {
+                       str += strlen(option);
+                       if (!*str || *str == ',')
+                               return true;
+               }
+
+               while (*str && *str != ',')
+                       str++;
+
+               if (*str == ',')
+                       str++;
+       }
+
+       return false;
+}