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-rw-r--r--arch/riscv/lib/uaccess.S78
1 files changed, 54 insertions, 24 deletions
diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index ec486e5369d9..4efea1b3326c 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -1,8 +1,10 @@
#include <linux/linkage.h>
-#include <asm-generic/export.h>
+#include <linux/export.h>
#include <asm/asm.h>
#include <asm/asm-extable.h>
#include <asm/csr.h>
+#include <asm/hwcap.h>
+#include <asm/alternative-macros.h>
.macro fixup op reg addr lbl
100:
@@ -10,15 +12,53 @@
_asm_extable 100b, \lbl
.endm
-ENTRY(__asm_copy_to_user)
-ENTRY(__asm_copy_from_user)
+SYM_FUNC_START(__asm_copy_to_user)
+#ifdef CONFIG_RISCV_ISA_V
+ ALTERNATIVE("j fallback_scalar_usercopy", "nop", 0, RISCV_ISA_EXT_ZVE32X, CONFIG_RISCV_ISA_V)
+ REG_L t0, riscv_v_usercopy_threshold
+ bltu a2, t0, fallback_scalar_usercopy
+ li a3, 1
+ tail enter_vector_usercopy
+#endif
+SYM_FUNC_END(__asm_copy_to_user)
+EXPORT_SYMBOL(__asm_copy_to_user)
+SYM_FUNC_ALIAS(__asm_copy_from_user, __asm_copy_to_user)
+EXPORT_SYMBOL(__asm_copy_from_user)
+SYM_FUNC_START(fallback_scalar_usercopy)
/* Enable access to user memory */
- li t6, SR_SUM
- csrs CSR_STATUS, t6
+ li t6, SR_SUM
+ csrs CSR_STATUS, t6
+ mv t6, ra
+
+ call fallback_scalar_usercopy_sum_enabled
- /* Save for return value */
- mv t5, a2
+ /* Disable access to user memory */
+ mv ra, t6
+ li t6, SR_SUM
+ csrc CSR_STATUS, t6
+ ret
+SYM_FUNC_END(fallback_scalar_usercopy)
+
+SYM_FUNC_START(__asm_copy_to_user_sum_enabled)
+#ifdef CONFIG_RISCV_ISA_V
+ ALTERNATIVE("j fallback_scalar_usercopy_sum_enabled", "nop", 0, RISCV_ISA_EXT_ZVE32X, CONFIG_RISCV_ISA_V)
+ REG_L t0, riscv_v_usercopy_threshold
+ bltu a2, t0, fallback_scalar_usercopy_sum_enabled
+ li a3, 0
+ tail enter_vector_usercopy
+#endif
+SYM_FUNC_END(__asm_copy_to_user_sum_enabled)
+SYM_FUNC_ALIAS(__asm_copy_from_user_sum_enabled, __asm_copy_to_user_sum_enabled)
+EXPORT_SYMBOL(__asm_copy_from_user_sum_enabled)
+EXPORT_SYMBOL(__asm_copy_to_user_sum_enabled)
+
+SYM_FUNC_START(fallback_scalar_usercopy_sum_enabled)
+ /*
+ * Save the terminal address which will be used to compute the number
+ * of bytes copied in case of a fixup exception.
+ */
+ add t5, a0, a2
/*
* Register allocation for code below:
@@ -33,7 +73,7 @@ ENTRY(__asm_copy_from_user)
* Use byte copy only if too small.
* SZREG holds 4 for RV32 and 8 for RV64
*/
- li a3, 9*SZREG /* size must be larger than size in word_copy */
+ li a3, 9*SZREG-1 /* size must >= (word_copy stride + SZREG-1) */
bltu a2, a3, .Lbyte_copy_tail
/*
@@ -92,7 +132,7 @@ ENTRY(__asm_copy_from_user)
fixup REG_S t4, 7*SZREG(a0), 10f
addi a0, a0, 8*SZREG
addi a1, a1, 8*SZREG
- bltu a0, t0, 2b
+ bleu a0, t0, 2b
addi t0, t0, 8*SZREG /* revert to original value */
j .Lbyte_copy_tail
@@ -167,24 +207,14 @@ ENTRY(__asm_copy_from_user)
bltu a0, t0, 4b /* t0 - end of dst */
.Lout_copy_user:
- /* Disable access to user memory */
- csrc CSR_STATUS, t6
li a0, 0
ret
-
- /* Exception fixup code */
10:
- /* Disable access to user memory */
- csrc CSR_STATUS, t6
- mv a0, t5
+ sub a0, t5, a0
ret
-ENDPROC(__asm_copy_to_user)
-ENDPROC(__asm_copy_from_user)
-EXPORT_SYMBOL(__asm_copy_to_user)
-EXPORT_SYMBOL(__asm_copy_from_user)
-
+SYM_FUNC_END(fallback_scalar_usercopy_sum_enabled)
-ENTRY(__clear_user)
+SYM_FUNC_START(__clear_user)
/* Enable access to user memory */
li t6, SR_SUM
@@ -228,7 +258,7 @@ ENTRY(__clear_user)
11:
/* Disable access to user memory */
csrc CSR_STATUS, t6
- mv a0, a1
+ sub a0, a3, a0
ret
-ENDPROC(__clear_user)
+SYM_FUNC_END(__clear_user)
EXPORT_SYMBOL(__clear_user)