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Diffstat (limited to 'arch/x86/boot/cmdline.c')
-rw-r--r--arch/x86/boot/cmdline.c73
1 files changed, 67 insertions, 6 deletions
diff --git a/arch/x86/boot/cmdline.c b/arch/x86/boot/cmdline.c
index 34bb778c435..625d21b0cd3 100644
--- a/arch/x86/boot/cmdline.c
+++ b/arch/x86/boot/cmdline.c
@@ -9,8 +9,6 @@
* ----------------------------------------------------------------------- */
/*
- * arch/i386/boot/cmdline.c
- *
* Simple command-line parser for early boot.
*/
@@ -29,9 +27,8 @@ static inline int myisspace(u8 c)
* Returns the length of the argument (regardless of if it was
* truncated to fit in the buffer), or -1 on not found.
*/
-int cmdline_find_option(const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize)
{
- u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
addr_t cptr;
char c;
int len = -1;
@@ -44,8 +41,8 @@ int cmdline_find_option(const char *option, char *buffer, int bufsize)
st_bufcpy /* Copying this to buffer */
} state = st_wordstart;
- if (!cmdline_ptr || cmdline_ptr >= 0x100000)
- return -1; /* No command line, or inaccessible */
+ if (!cmdline_ptr)
+ return -1; /* No command line */
cptr = cmdline_ptr & 0xf;
set_fs(cmdline_ptr >> 4);
@@ -95,3 +92,67 @@ int cmdline_find_option(const char *option, char *buffer, int bufsize)
return len;
}
+
+/*
+ * Find a boolean option (like quiet,noapic,nosmp....)
+ *
+ * Returns the position of that option (starts counting with 1)
+ * or 0 on not found
+ */
+int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option)
+{
+ addr_t cptr;
+ char c;
+ int pos = 0, wstart = 0;
+ const char *opptr = NULL;
+ enum {
+ st_wordstart, /* Start of word/after whitespace */
+ st_wordcmp, /* Comparing this word */
+ st_wordskip, /* Miscompare, skip */
+ } state = st_wordstart;
+
+ if (!cmdline_ptr)
+ return -1; /* No command line */
+
+ cptr = cmdline_ptr & 0xf;
+ set_fs(cmdline_ptr >> 4);
+
+ while (cptr < 0x10000) {
+ c = rdfs8(cptr++);
+ pos++;
+
+ switch (state) {
+ case st_wordstart:
+ if (!c)
+ return 0;
+ else if (myisspace(c))
+ break;
+
+ state = st_wordcmp;
+ opptr = option;
+ wstart = pos;
+ /* fall through */
+
+ case st_wordcmp:
+ if (!*opptr)
+ if (!c || myisspace(c))
+ return wstart;
+ else
+ state = st_wordskip;
+ else if (!c)
+ return 0;
+ else if (c != *opptr++)
+ state = st_wordskip;
+ break;
+
+ case st_wordskip:
+ if (!c)
+ return 0;
+ else if (myisspace(c))
+ state = st_wordstart;
+ break;
+ }
+ }
+
+ return 0; /* Buffer overrun */
+}