diff options
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/lib/cmdline.c | 84 | ||||
| -rw-r--r-- | arch/x86/lib/thunk_32.S | 3 | ||||
| -rw-r--r-- | arch/x86/lib/thunk_64.S | 3 |
4 files changed, 90 insertions, 2 deletions
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index eabcb6e6a900..4d4f96a27638 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -16,7 +16,7 @@ clean-files := inat-tables.c obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o -lib-y := delay.o misc.o +lib-y := delay.o misc.o cmdline.o lib-y += thunk_$(BITS).o lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o lib-y += memcpy_$(BITS).o diff --git a/arch/x86/lib/cmdline.c b/arch/x86/lib/cmdline.c new file mode 100644 index 000000000000..422db000d727 --- /dev/null +++ b/arch/x86/lib/cmdline.c @@ -0,0 +1,84 @@ +/* + * This file is part of the Linux kernel, and is made available under + * the terms of the GNU General Public License version 2. + * + * Misc librarized functions for cmdline poking. + */ +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/ctype.h> +#include <asm/setup.h> + +static inline int myisspace(u8 c) +{ + return c <= ' '; /* Close enough approximation */ +} + +/** + * Find a boolean option (like quiet,noapic,nosmp....) + * + * @cmdline: the cmdline string + * @option: option string to look for + * + * Returns the position of that @option (starts counting with 1) + * or 0 on not found. + */ +int cmdline_find_option_bool(const char *cmdline, const char *option) +{ + char c; + int len, pos = 0, wstart = 0; + const char *opptr = NULL; + enum { + st_wordstart = 0, /* Start of word/after whitespace */ + st_wordcmp, /* Comparing this word */ + st_wordskip, /* Miscompare, skip */ + } state = st_wordstart; + + if (!cmdline) + return -1; /* No command line */ + + len = min_t(int, strlen(cmdline), COMMAND_LINE_SIZE); + if (!len) + return 0; + + while (len--) { + c = *(char *)cmdline++; + 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; + else if (!len) /* last word and is matching */ + return wstart; + break; + + case st_wordskip: + if (!c) + return 0; + else if (myisspace(c)) + state = st_wordstart; + break; + } + } + + return 0; /* Buffer overrun */ +} diff --git a/arch/x86/lib/thunk_32.S b/arch/x86/lib/thunk_32.S index 2930ae05d773..28f85c916712 100644 --- a/arch/x86/lib/thunk_32.S +++ b/arch/x86/lib/thunk_32.S @@ -4,8 +4,8 @@ * (inspired by Andi Kleen's thunk_64.S) * Subject to the GNU public license, v.2. No warranty of any kind. */ - #include <linux/linkage.h> + #include <asm/asm.h> #ifdef CONFIG_TRACE_IRQFLAGS /* put return address in eax (arg1) */ @@ -22,6 +22,7 @@ popl %ecx popl %eax ret + _ASM_NOKPROBE(\name) .endm thunk_ra trace_hardirqs_on_thunk,trace_hardirqs_on_caller diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S index a63efd6bb6a5..92d9feaff42b 100644 --- a/arch/x86/lib/thunk_64.S +++ b/arch/x86/lib/thunk_64.S @@ -8,6 +8,7 @@ #include <linux/linkage.h> #include <asm/dwarf2.h> #include <asm/calling.h> +#include <asm/asm.h> /* rdi: arg1 ... normal C conventions. rax is saved/restored. */ .macro THUNK name, func, put_ret_addr_in_rdi=0 @@ -25,6 +26,7 @@ call \func jmp restore CFI_ENDPROC + _ASM_NOKPROBE(\name) .endm #ifdef CONFIG_TRACE_IRQFLAGS @@ -43,3 +45,4 @@ restore: RESTORE_ARGS ret CFI_ENDPROC + _ASM_NOKPROBE(restore) |