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-rw-r--r--arch/s390/include/asm/alternative-asm.h70
1 files changed, 9 insertions, 61 deletions
diff --git a/arch/s390/include/asm/alternative-asm.h b/arch/s390/include/asm/alternative-asm.h
index 955d620db23e..7db046596b93 100644
--- a/arch/s390/include/asm/alternative-asm.h
+++ b/arch/s390/include/asm/alternative-asm.h
@@ -5,19 +5,6 @@
#ifdef __ASSEMBLY__
/*
- * Check the length of an instruction sequence. The length may not be larger
- * than 254 bytes and it has to be divisible by 2.
- */
-.macro alt_len_check start,end
- .if ( \end - \start ) > 254
- .error "cpu alternatives does not support instructions blocks > 254 bytes\n"
- .endif
- .if ( \end - \start ) % 2
- .error "cpu alternatives instructions length is odd\n"
- .endif
-.endm
-
-/*
* Issue one struct alt_instr descriptor entry (need to put it into
* the section .altinstructions, see below). This entry contains
* enough information for the alternatives patching code to patch an
@@ -28,60 +15,29 @@
.long \alt_start - .
.word \feature
.byte \orig_end - \orig_start
- .byte \alt_end - \alt_start
-.endm
-
-/*
- * Fill up @bytes with nops. The macro emits 6-byte nop instructions
- * for the bulk of the area, possibly followed by a 4-byte and/or
- * a 2-byte nop if the size of the area is not divisible by 6.
- */
-.macro alt_pad_fill bytes
- .fill ( \bytes ) / 6, 6, 0xc0040000
- .fill ( \bytes ) % 6 / 4, 4, 0x47000000
- .fill ( \bytes ) % 6 % 4 / 2, 2, 0x0700
-.endm
-
-/*
- * Fill up @bytes with nops. If the number of bytes is larger
- * than 6, emit a jg instruction to branch over all nops, then
- * fill an area of size (@bytes - 6) with nop instructions.
- */
-.macro alt_pad bytes
- .if ( \bytes > 0 )
- .if ( \bytes > 6 )
- jg . + \bytes
- alt_pad_fill \bytes - 6
- .else
- alt_pad_fill \bytes
- .endif
- .endif
+ .org . - ( \orig_end - \orig_start ) + ( \alt_end - \alt_start )
+ .org . - ( \alt_end - \alt_start ) + ( \orig_end - \orig_start )
.endm
/*
* Define an alternative between two instructions. If @feature is
* present, early code in apply_alternatives() replaces @oldinstr with
- * @newinstr. ".skip" directive takes care of proper instruction padding
- * in case @newinstr is longer than @oldinstr.
+ * @newinstr.
*/
.macro ALTERNATIVE oldinstr, newinstr, feature
.pushsection .altinstr_replacement,"ax"
770: \newinstr
771: .popsection
772: \oldinstr
-773: alt_len_check 770b, 771b
- alt_len_check 772b, 773b
- alt_pad ( ( 771b - 770b ) - ( 773b - 772b ) )
-774: .pushsection .altinstructions,"a"
- alt_entry 772b, 774b, 770b, 771b, \feature
+773: .pushsection .altinstructions,"a"
+ alt_entry 772b, 773b, 770b, 771b, \feature
.popsection
.endm
/*
* Define an alternative between two instructions. If @feature is
* present, early code in apply_alternatives() replaces @oldinstr with
- * @newinstr. ".skip" directive takes care of proper instruction padding
- * in case @newinstr is longer than @oldinstr.
+ * @newinstr.
*/
.macro ALTERNATIVE_2 oldinstr, newinstr1, feature1, newinstr2, feature2
.pushsection .altinstr_replacement,"ax"
@@ -89,17 +45,9 @@
771: \newinstr2
772: .popsection
773: \oldinstr
-774: alt_len_check 770b, 771b
- alt_len_check 771b, 772b
- alt_len_check 773b, 774b
- .if ( 771b - 770b > 772b - 771b )
- alt_pad ( ( 771b - 770b ) - ( 774b - 773b ) )
- .else
- alt_pad ( ( 772b - 771b ) - ( 774b - 773b ) )
- .endif
-775: .pushsection .altinstructions,"a"
- alt_entry 773b, 775b, 770b, 771b,\feature1
- alt_entry 773b, 775b, 771b, 772b,\feature2
+774: .pushsection .altinstructions,"a"
+ alt_entry 773b, 774b, 770b, 771b,\feature1
+ alt_entry 773b, 774b, 771b, 772b,\feature2
.popsection
.endm