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Diffstat (limited to 'arch/x86/include/asm/alternative.h')
-rw-r--r--arch/x86/include/asm/alternative.h132
1 files changed, 76 insertions, 56 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index 7659217f4d49..e2975a32d443 100644
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -6,8 +6,10 @@
#include <linux/stringify.h>
#include <asm/asm.h>
-#define ALTINSTR_FLAG_INV (1 << 15)
-#define ALT_NOT(feat) ((feat) | ALTINSTR_FLAG_INV)
+#define ALT_FLAGS_SHIFT 16
+
+#define ALT_FLAG_NOT BIT(0)
+#define ALT_NOT(feature) ((ALT_FLAG_NOT << ALT_FLAGS_SHIFT) | (feature))
#ifndef __ASSEMBLY__
@@ -59,10 +61,27 @@
".long 999b - .\n\t" \
".popsection\n\t"
+/*
+ * The patching flags are part of the upper bits of the @ft_flags parameter when
+ * specifying them. The split is currently like this:
+ *
+ * [31... flags ...16][15... CPUID feature bit ...0]
+ *
+ * but since this is all hidden in the macros argument being split, those fields can be
+ * extended in the future to fit in a u64 or however the need arises.
+ */
struct alt_instr {
s32 instr_offset; /* original instruction */
s32 repl_offset; /* offset to replacement instruction */
- u16 cpuid; /* cpuid bit set for replacement */
+
+ union {
+ struct {
+ u32 cpuid: 16; /* CPUID bit set for replacement */
+ u32 flags: 16; /* patching control flags */
+ };
+ u32 ft_flags;
+ };
+
u8 instrlen; /* length of original instruction */
u8 replacementlen; /* length of new instruction */
} __packed;
@@ -182,10 +201,10 @@ static inline int alternatives_text_reserved(void *start, void *end)
" - (" alt_slen ")), 0x90\n" \
alt_end_marker ":\n"
-#define ALTINSTR_ENTRY(feature, num) \
+#define ALTINSTR_ENTRY(ft_flags, num) \
" .long 661b - .\n" /* label */ \
" .long " b_replacement(num)"f - .\n" /* new instruction */ \
- " .word " __stringify(feature) "\n" /* feature bit */ \
+ " .4byte " __stringify(ft_flags) "\n" /* feature + flags */ \
" .byte " alt_total_slen "\n" /* source len */ \
" .byte " alt_rlen(num) "\n" /* replacement len */
@@ -194,20 +213,20 @@ static inline int alternatives_text_reserved(void *start, void *end)
b_replacement(num)":\n\t" newinstr "\n" e_replacement(num) ":\n"
/* alternative assembly primitive: */
-#define ALTERNATIVE(oldinstr, newinstr, feature) \
+#define ALTERNATIVE(oldinstr, newinstr, ft_flags) \
OLDINSTR(oldinstr, 1) \
".pushsection .altinstructions,\"a\"\n" \
- ALTINSTR_ENTRY(feature, 1) \
+ ALTINSTR_ENTRY(ft_flags, 1) \
".popsection\n" \
".pushsection .altinstr_replacement, \"ax\"\n" \
ALTINSTR_REPLACEMENT(newinstr, 1) \
".popsection\n"
-#define ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2)\
+#define ALTERNATIVE_2(oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2) \
OLDINSTR_2(oldinstr, 1, 2) \
".pushsection .altinstructions,\"a\"\n" \
- ALTINSTR_ENTRY(feature1, 1) \
- ALTINSTR_ENTRY(feature2, 2) \
+ ALTINSTR_ENTRY(ft_flags1, 1) \
+ ALTINSTR_ENTRY(ft_flags2, 2) \
".popsection\n" \
".pushsection .altinstr_replacement, \"ax\"\n" \
ALTINSTR_REPLACEMENT(newinstr1, 1) \
@@ -215,21 +234,22 @@ static inline int alternatives_text_reserved(void *start, void *end)
".popsection\n"
/* If @feature is set, patch in @newinstr_yes, otherwise @newinstr_no. */
-#define ALTERNATIVE_TERNARY(oldinstr, feature, newinstr_yes, newinstr_no) \
+#define ALTERNATIVE_TERNARY(oldinstr, ft_flags, newinstr_yes, newinstr_no) \
ALTERNATIVE_2(oldinstr, newinstr_no, X86_FEATURE_ALWAYS, \
- newinstr_yes, feature)
-
-#define ALTERNATIVE_3(oldinsn, newinsn1, feat1, newinsn2, feat2, newinsn3, feat3) \
- OLDINSTR_3(oldinsn, 1, 2, 3) \
- ".pushsection .altinstructions,\"a\"\n" \
- ALTINSTR_ENTRY(feat1, 1) \
- ALTINSTR_ENTRY(feat2, 2) \
- ALTINSTR_ENTRY(feat3, 3) \
- ".popsection\n" \
- ".pushsection .altinstr_replacement, \"ax\"\n" \
- ALTINSTR_REPLACEMENT(newinsn1, 1) \
- ALTINSTR_REPLACEMENT(newinsn2, 2) \
- ALTINSTR_REPLACEMENT(newinsn3, 3) \
+ newinstr_yes, ft_flags)
+
+#define ALTERNATIVE_3(oldinsn, newinsn1, ft_flags1, newinsn2, ft_flags2, \
+ newinsn3, ft_flags3) \
+ OLDINSTR_3(oldinsn, 1, 2, 3) \
+ ".pushsection .altinstructions,\"a\"\n" \
+ ALTINSTR_ENTRY(ft_flags1, 1) \
+ ALTINSTR_ENTRY(ft_flags2, 2) \
+ ALTINSTR_ENTRY(ft_flags3, 3) \
+ ".popsection\n" \
+ ".pushsection .altinstr_replacement, \"ax\"\n" \
+ ALTINSTR_REPLACEMENT(newinsn1, 1) \
+ ALTINSTR_REPLACEMENT(newinsn2, 2) \
+ ALTINSTR_REPLACEMENT(newinsn3, 3) \
".popsection\n"
/*
@@ -244,14 +264,14 @@ static inline int alternatives_text_reserved(void *start, void *end)
* For non barrier like inlines please define new variants
* without volatile and memory clobber.
*/
-#define alternative(oldinstr, newinstr, feature) \
- asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, feature) : : : "memory")
+#define alternative(oldinstr, newinstr, ft_flags) \
+ asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, ft_flags) : : : "memory")
-#define alternative_2(oldinstr, newinstr1, feature1, newinstr2, feature2) \
- asm_inline volatile(ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2) ::: "memory")
+#define alternative_2(oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2) \
+ asm_inline volatile(ALTERNATIVE_2(oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2) ::: "memory")
-#define alternative_ternary(oldinstr, feature, newinstr_yes, newinstr_no) \
- asm_inline volatile(ALTERNATIVE_TERNARY(oldinstr, feature, newinstr_yes, newinstr_no) ::: "memory")
+#define alternative_ternary(oldinstr, ft_flags, newinstr_yes, newinstr_no) \
+ asm_inline volatile(ALTERNATIVE_TERNARY(oldinstr, ft_flags, newinstr_yes, newinstr_no) ::: "memory")
/*
* Alternative inline assembly with input.
@@ -261,8 +281,8 @@ static inline int alternatives_text_reserved(void *start, void *end)
* Argument numbers start with 1.
* Leaving an unused argument 0 to keep API compatibility.
*/
-#define alternative_input(oldinstr, newinstr, feature, input...) \
- asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, feature) \
+#define alternative_input(oldinstr, newinstr, ft_flags, input...) \
+ asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, ft_flags) \
: : "i" (0), ## input)
/*
@@ -273,20 +293,20 @@ static inline int alternatives_text_reserved(void *start, void *end)
* Otherwise, if CPU has feature1, newinstr1 is used.
* Otherwise, oldinstr is used.
*/
-#define alternative_input_2(oldinstr, newinstr1, feature1, newinstr2, \
- feature2, input...) \
- asm_inline volatile(ALTERNATIVE_2(oldinstr, newinstr1, feature1, \
- newinstr2, feature2) \
+#define alternative_input_2(oldinstr, newinstr1, ft_flags1, newinstr2, \
+ ft_flags2, input...) \
+ asm_inline volatile(ALTERNATIVE_2(oldinstr, newinstr1, ft_flags1, \
+ newinstr2, ft_flags2) \
: : "i" (0), ## input)
/* Like alternative_input, but with a single output argument */
-#define alternative_io(oldinstr, newinstr, feature, output, input...) \
- asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, feature) \
+#define alternative_io(oldinstr, newinstr, ft_flags, output, input...) \
+ asm_inline volatile (ALTERNATIVE(oldinstr, newinstr, ft_flags) \
: output : "i" (0), ## input)
/* Like alternative_io, but for replacing a direct call with another one. */
-#define alternative_call(oldfunc, newfunc, feature, output, input...) \
- asm_inline volatile (ALTERNATIVE("call %P[old]", "call %P[new]", feature) \
+#define alternative_call(oldfunc, newfunc, ft_flags, output, input...) \
+ asm_inline volatile (ALTERNATIVE("call %P[old]", "call %P[new]", ft_flags) \
: output : [old] "i" (oldfunc), [new] "i" (newfunc), ## input)
/*
@@ -295,10 +315,10 @@ static inline int alternatives_text_reserved(void *start, void *end)
* Otherwise, if CPU has feature1, function1 is used.
* Otherwise, old function is used.
*/
-#define alternative_call_2(oldfunc, newfunc1, feature1, newfunc2, feature2, \
+#define alternative_call_2(oldfunc, newfunc1, ft_flags1, newfunc2, ft_flags2, \
output, input...) \
- asm_inline volatile (ALTERNATIVE_2("call %P[old]", "call %P[new1]", feature1,\
- "call %P[new2]", feature2) \
+ asm_inline volatile (ALTERNATIVE_2("call %P[old]", "call %P[new1]", ft_flags1,\
+ "call %P[new2]", ft_flags2) \
: output, ASM_CALL_CONSTRAINT \
: [old] "i" (oldfunc), [new1] "i" (newfunc1), \
[new2] "i" (newfunc2), ## input)
@@ -347,10 +367,10 @@ static inline int alternatives_text_reserved(void *start, void *end)
* enough information for the alternatives patching code to patch an
* instruction. See apply_alternatives().
*/
-.macro altinstruction_entry orig alt feature orig_len alt_len
+.macro altinstr_entry orig alt ft_flags orig_len alt_len
.long \orig - .
.long \alt - .
- .word \feature
+ .4byte \ft_flags
.byte \orig_len
.byte \alt_len
.endm
@@ -361,7 +381,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
* @newinstr. ".skip" directive takes care of proper instruction padding
* in case @newinstr is longer than @oldinstr.
*/
-.macro ALTERNATIVE oldinstr, newinstr, feature
+.macro ALTERNATIVE oldinstr, newinstr, ft_flags
140:
\oldinstr
141:
@@ -369,7 +389,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
142:
.pushsection .altinstructions,"a"
- altinstruction_entry 140b,143f,\feature,142b-140b,144f-143f
+ altinstr_entry 140b,143f,\ft_flags,142b-140b,144f-143f
.popsection
.pushsection .altinstr_replacement,"ax"
@@ -399,7 +419,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
* has @feature1, it replaces @oldinstr with @newinstr1. If CPU has
* @feature2, it replaces @oldinstr with @feature2.
*/
-.macro ALTERNATIVE_2 oldinstr, newinstr1, feature1, newinstr2, feature2
+.macro ALTERNATIVE_2 oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2
140:
\oldinstr
141:
@@ -408,8 +428,8 @@ static inline int alternatives_text_reserved(void *start, void *end)
142:
.pushsection .altinstructions,"a"
- altinstruction_entry 140b,143f,\feature1,142b-140b,144f-143f
- altinstruction_entry 140b,144f,\feature2,142b-140b,145f-144f
+ altinstr_entry 140b,143f,\ft_flags1,142b-140b,144f-143f
+ altinstr_entry 140b,144f,\ft_flags2,142b-140b,145f-144f
.popsection
.pushsection .altinstr_replacement,"ax"
@@ -421,7 +441,7 @@ static inline int alternatives_text_reserved(void *start, void *end)
.popsection
.endm
-.macro ALTERNATIVE_3 oldinstr, newinstr1, feature1, newinstr2, feature2, newinstr3, feature3
+.macro ALTERNATIVE_3 oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2, newinstr3, ft_flags3
140:
\oldinstr
141:
@@ -430,9 +450,9 @@ static inline int alternatives_text_reserved(void *start, void *end)
142:
.pushsection .altinstructions,"a"
- altinstruction_entry 140b,143f,\feature1,142b-140b,144f-143f
- altinstruction_entry 140b,144f,\feature2,142b-140b,145f-144f
- altinstruction_entry 140b,145f,\feature3,142b-140b,146f-145f
+ altinstr_entry 140b,143f,\ft_flags1,142b-140b,144f-143f
+ altinstr_entry 140b,144f,\ft_flags2,142b-140b,145f-144f
+ altinstr_entry 140b,145f,\ft_flags3,142b-140b,146f-145f
.popsection
.pushsection .altinstr_replacement,"ax"
@@ -447,9 +467,9 @@ static inline int alternatives_text_reserved(void *start, void *end)
.endm
/* If @feature is set, patch in @newinstr_yes, otherwise @newinstr_no. */
-#define ALTERNATIVE_TERNARY(oldinstr, feature, newinstr_yes, newinstr_no) \
+#define ALTERNATIVE_TERNARY(oldinstr, ft_flags, newinstr_yes, newinstr_no) \
ALTERNATIVE_2 oldinstr, newinstr_no, X86_FEATURE_ALWAYS, \
- newinstr_yes, feature
+ newinstr_yes, ft_flags
#endif /* __ASSEMBLY__ */