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| /* SPDX-License-Identifier: GPL-2.0 */
| /*
| * String handling functions.
| *
| * Copyright IBM Corp. 2012
| */
|
| #include <linux/linkage.h>
| #include <asm/export.h>
| #include <asm/nospec-insn.h>
|
| GEN_BR_THUNK %r14
|
| /*
| * void *memmove(void *dest, const void *src, size_t n)
| */
| WEAK(memmove)
| ENTRY(__memmove)
| ltgr %r4,%r4
| lgr %r1,%r2
| jz .Lmemmove_exit
| aghi %r4,-1
| clgr %r2,%r3
| jnh .Lmemmove_forward
| la %r5,1(%r4,%r3)
| clgr %r2,%r5
| jl .Lmemmove_reverse
| .Lmemmove_forward:
| srlg %r0,%r4,8
| ltgr %r0,%r0
| jz .Lmemmove_forward_remainder
| .Lmemmove_forward_loop:
| mvc 0(256,%r1),0(%r3)
| la %r1,256(%r1)
| la %r3,256(%r3)
| brctg %r0,.Lmemmove_forward_loop
| .Lmemmove_forward_remainder:
| larl %r5,.Lmemmove_mvc
| ex %r4,0(%r5)
| .Lmemmove_exit:
| BR_EX %r14
| .Lmemmove_reverse:
| ic %r0,0(%r4,%r3)
| stc %r0,0(%r4,%r1)
| brctg %r4,.Lmemmove_reverse
| ic %r0,0(%r4,%r3)
| stc %r0,0(%r4,%r1)
| BR_EX %r14
| .Lmemmove_mvc:
| mvc 0(1,%r1),0(%r3)
| ENDPROC(__memmove)
| EXPORT_SYMBOL(memmove)
|
| /*
| * memset implementation
| *
| * This code corresponds to the C construct below. We do distinguish
| * between clearing (c == 0) and setting a memory array (c != 0) simply
| * because nearly all memset invocations in the kernel clear memory and
| * the xc instruction is preferred in such cases.
| *
| * void *memset(void *s, int c, size_t n)
| * {
| * if (likely(c == 0))
| * return __builtin_memset(s, 0, n);
| * return __builtin_memset(s, c, n);
| * }
| */
| WEAK(memset)
| ENTRY(__memset)
| ltgr %r4,%r4
| jz .Lmemset_exit
| ltgr %r3,%r3
| jnz .Lmemset_fill
| aghi %r4,-1
| srlg %r3,%r4,8
| ltgr %r3,%r3
| lgr %r1,%r2
| jz .Lmemset_clear_remainder
| .Lmemset_clear_loop:
| xc 0(256,%r1),0(%r1)
| la %r1,256(%r1)
| brctg %r3,.Lmemset_clear_loop
| .Lmemset_clear_remainder:
| larl %r3,.Lmemset_xc
| ex %r4,0(%r3)
| .Lmemset_exit:
| BR_EX %r14
| .Lmemset_fill:
| cghi %r4,1
| lgr %r1,%r2
| je .Lmemset_fill_exit
| aghi %r4,-2
| srlg %r5,%r4,8
| ltgr %r5,%r5
| jz .Lmemset_fill_remainder
| .Lmemset_fill_loop:
| stc %r3,0(%r1)
| mvc 1(255,%r1),0(%r1)
| la %r1,256(%r1)
| brctg %r5,.Lmemset_fill_loop
| .Lmemset_fill_remainder:
| stc %r3,0(%r1)
| larl %r5,.Lmemset_mvc
| ex %r4,0(%r5)
| BR_EX %r14
| .Lmemset_fill_exit:
| stc %r3,0(%r1)
| BR_EX %r14
| .Lmemset_xc:
| xc 0(1,%r1),0(%r1)
| .Lmemset_mvc:
| mvc 1(1,%r1),0(%r1)
| ENDPROC(__memset)
| EXPORT_SYMBOL(memset)
|
| /*
| * memcpy implementation
| *
| * void *memcpy(void *dest, const void *src, size_t n)
| */
| WEAK(memcpy)
| ENTRY(__memcpy)
| ltgr %r4,%r4
| jz .Lmemcpy_exit
| aghi %r4,-1
| srlg %r5,%r4,8
| ltgr %r5,%r5
| lgr %r1,%r2
| jnz .Lmemcpy_loop
| .Lmemcpy_remainder:
| larl %r5,.Lmemcpy_mvc
| ex %r4,0(%r5)
| .Lmemcpy_exit:
| BR_EX %r14
| .Lmemcpy_loop:
| mvc 0(256,%r1),0(%r3)
| la %r1,256(%r1)
| la %r3,256(%r3)
| brctg %r5,.Lmemcpy_loop
| j .Lmemcpy_remainder
| .Lmemcpy_mvc:
| mvc 0(1,%r1),0(%r3)
| ENDPROC(__memcpy)
| EXPORT_SYMBOL(memcpy)
|
| /*
| * __memset16/32/64
| *
| * void *__memset16(uint16_t *s, uint16_t v, size_t count)
| * void *__memset32(uint32_t *s, uint32_t v, size_t count)
| * void *__memset64(uint64_t *s, uint64_t v, size_t count)
| */
| .macro __MEMSET bits,bytes,insn
| ENTRY(__memset\bits)
| ltgr %r4,%r4
| jz .L__memset_exit\bits
| cghi %r4,\bytes
| je .L__memset_store\bits
| aghi %r4,-(\bytes+1)
| srlg %r5,%r4,8
| ltgr %r5,%r5
| lgr %r1,%r2
| jz .L__memset_remainder\bits
| .L__memset_loop\bits:
| \insn %r3,0(%r1)
| mvc \bytes(256-\bytes,%r1),0(%r1)
| la %r1,256(%r1)
| brctg %r5,.L__memset_loop\bits
| .L__memset_remainder\bits:
| \insn %r3,0(%r1)
| larl %r5,.L__memset_mvc\bits
| ex %r4,0(%r5)
| BR_EX %r14
| .L__memset_store\bits:
| \insn %r3,0(%r2)
| .L__memset_exit\bits:
| BR_EX %r14
| .L__memset_mvc\bits:
| mvc \bytes(1,%r1),0(%r1)
| ENDPROC(__memset\bits)
| .endm
|
| __MEMSET 16,2,sth
| EXPORT_SYMBOL(__memset16)
|
| __MEMSET 32,4,st
| EXPORT_SYMBOL(__memset32)
|
| __MEMSET 64,8,stg
| EXPORT_SYMBOL(__memset64)
|
|
