Google Git
Sign in
gfiber / kernel / lockdown / 1cfdbf4d5f51ffb8837de504babed04e9c35fae4 / . / arch / metag / lib / usercopy.c
blob: b3ebfe9c8e886a5c0f8f309b1a390ac286208a86 [file] [log] [blame]
/*
* User address space access functions.
* The non-inlined parts of asm-metag/uaccess.h are here.
*
* Copyright (C) 2006, Imagination Technologies.
* Copyright (C) 2000, Axis Communications AB.
*
* Written by Hans-Peter Nilsson.
* Pieces used from memcpy, originally by Kenny Ranerup long time ago.
* Modified for Meta by Will Newton.
*/
#include <linux/export.h>
#include <linux/uaccess.h>
#include <asm/cache.h> /* def of L1_CACHE_BYTES */
#define USE_RAPF
#define RAPF_MIN_BUF_SIZE (3*L1_CACHE_BYTES)
/* The "double write" in this code is because the Meta will not fault
* immediately unless the memory pipe is forced to by e.g. a data stall or
* another memory op. The second write should be discarded by the write
* combiner so should have virtually no cost.
*/
#define __asm_copy_user_cont(to, from, ret, COPY, FIXUP, TENTRY) \
asm volatile ( \
COPY \
"1:\n" \
" .section .fixup,\"ax\"\n" \
" MOV D1Ar1,#0\n" \
FIXUP \
" MOVT D1Ar1,#HI(1b)\n" \
" JUMP D1Ar1,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
TENTRY \
" .previous\n" \
: "=r" (to), "=r" (from), "=r" (ret) \
: "0" (to), "1" (from), "2" (ret) \
: "D1Ar1", "memory")
#define __asm_copy_to_user_1(to, from, ret) \
__asm_copy_user_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"2: SETB [%0++],D1Ar1\n", \
"3: ADD %2,%2,#1\n", \
" .long 2b,3b\n")
#define __asm_copy_to_user_2x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_user_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
" SETW [%0],D1Ar1\n" \
"2: SETW [%0++],D1Ar1\n" COPY, \
"3: ADD %2,%2,#2\n" FIXUP, \
" .long 2b,3b\n" TENTRY)
#define __asm_copy_to_user_2(to, from, ret) \
__asm_copy_to_user_2x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_3(to, from, ret) \
__asm_copy_to_user_2x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"4: SETB [%0++],D1Ar1\n", \
"5: ADD %2,%2,#1\n", \
" .long 4b,5b\n")
#define __asm_copy_to_user_4x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_user_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
" SETD [%0],D1Ar1\n" \
"2: SETD [%0++],D1Ar1\n" COPY, \
"3: ADD %2,%2,#4\n" FIXUP, \
" .long 2b,3b\n" TENTRY)
#define __asm_copy_to_user_4(to, from, ret) \
__asm_copy_to_user_4x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_5(to, from, ret) \
__asm_copy_to_user_4x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"4: SETB [%0++],D1Ar1\n", \
"5: ADD %2,%2,#1\n", \
" .long 4b,5b\n")
#define __asm_copy_to_user_6x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_4x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
" SETW [%0],D1Ar1\n" \
"4: SETW [%0++],D1Ar1\n" COPY, \
"5: ADD %2,%2,#2\n" FIXUP, \
" .long 4b,5b\n" TENTRY)
#define __asm_copy_to_user_6(to, from, ret) \
__asm_copy_to_user_6x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_7(to, from, ret) \
__asm_copy_to_user_6x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"6: SETB [%0++],D1Ar1\n", \
"7: ADD %2,%2,#1\n", \
" .long 6b,7b\n")
#define __asm_copy_to_user_8x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_4x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
" SETD [%0],D1Ar1\n" \
"4: SETD [%0++],D1Ar1\n" COPY, \
"5: ADD %2,%2,#4\n" FIXUP, \
" .long 4b,5b\n" TENTRY)
#define __asm_copy_to_user_8(to, from, ret) \
__asm_copy_to_user_8x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_9(to, from, ret) \
__asm_copy_to_user_8x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"6: SETB [%0++],D1Ar1\n", \
"7: ADD %2,%2,#1\n", \
" .long 6b,7b\n")
#define __asm_copy_to_user_10x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_8x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
" SETW [%0],D1Ar1\n" \
"6: SETW [%0++],D1Ar1\n" COPY, \
"7: ADD %2,%2,#2\n" FIXUP, \
" .long 6b,7b\n" TENTRY)
#define __asm_copy_to_user_10(to, from, ret) \
__asm_copy_to_user_10x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_11(to, from, ret) \
__asm_copy_to_user_10x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"8: SETB [%0++],D1Ar1\n", \
"9: ADD %2,%2,#1\n", \
" .long 8b,9b\n")
#define __asm_copy_to_user_12x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_8x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
" SETD [%0],D1Ar1\n" \
"6: SETD [%0++],D1Ar1\n" COPY, \
"7: ADD %2,%2,#4\n" FIXUP, \
" .long 6b,7b\n" TENTRY)
#define __asm_copy_to_user_12(to, from, ret) \
__asm_copy_to_user_12x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_13(to, from, ret) \
__asm_copy_to_user_12x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"8: SETB [%0++],D1Ar1\n", \
"9: ADD %2,%2,#1\n", \
" .long 8b,9b\n")
#define __asm_copy_to_user_14x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_12x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
" SETW [%0],D1Ar1\n" \
"8: SETW [%0++],D1Ar1\n" COPY, \
"9: ADD %2,%2,#2\n" FIXUP, \
" .long 8b,9b\n" TENTRY)
#define __asm_copy_to_user_14(to, from, ret) \
__asm_copy_to_user_14x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_15(to, from, ret) \
__asm_copy_to_user_14x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
" SETB [%0],D1Ar1\n" \
"10: SETB [%0++],D1Ar1\n", \
"11: ADD %2,%2,#1\n", \
" .long 10b,11b\n")
#define __asm_copy_to_user_16x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_to_user_12x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
" SETD [%0],D1Ar1\n" \
"8: SETD [%0++],D1Ar1\n" COPY, \
"9: ADD %2,%2,#4\n" FIXUP, \
" .long 8b,9b\n" TENTRY)
#define __asm_copy_to_user_16(to, from, ret) \
__asm_copy_to_user_16x_cont(to, from, ret, "", "", "")
#define __asm_copy_to_user_8x64(to, from, ret) \
asm volatile ( \
" GETL D0Ar2,D1Ar1,[%1++]\n" \
" SETL [%0],D0Ar2,D1Ar1\n" \
"2: SETL [%0++],D0Ar2,D1Ar1\n" \
"1:\n" \
" .section .fixup,\"ax\"\n" \
"3: ADD %2,%2,#8\n" \
" MOVT D0Ar2,#HI(1b)\n" \
" JUMP D0Ar2,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .long 2b,3b\n" \
" .previous\n" \
: "=r" (to), "=r" (from), "=r" (ret) \
: "0" (to), "1" (from), "2" (ret) \
: "D1Ar1", "D0Ar2", "memory")
/*
* optimized copying loop using RAPF when 64 bit aligned
*
* n will be automatically decremented inside the loop
* ret will be left intact. if error occurs we will rewind
* so that the original non optimized code will fill up
* this value correctly.
*
* on fault:
* > n will hold total number of uncopied bytes
*
* > {'to','from'} will be rewind back so that
* the non-optimized code will do the proper fix up
*
* DCACHE drops the cacheline which helps in reducing cache
* pollution.
*
* We introduce an extra SETL at the end of the loop to
* ensure we don't fall off the loop before we catch all
* erros.
*
* NOTICE:
* LSM_STEP in TXSTATUS must be cleared in fix up code.
* since we're using M{S,G}ETL, a fault might happen at
* any address in the middle of M{S,G}ETL causing
* the value of LSM_STEP to be incorrect which can
* cause subsequent use of M{S,G}ET{L,D} to go wrong.
* ie: if LSM_STEP was 1 when a fault occurs, the
* next call to M{S,G}ET{L,D} will skip the first
* copy/getting as it think that the first 1 has already
* been done.
*
*/
#define __asm_copy_user_64bit_rapf_loop( \
to, from, ret, n, id, FIXUP) \
asm volatile ( \
".balign 8\n" \
"MOV RAPF, %1\n" \
"MSETL [A0StP++], D0Ar6, D0FrT, D0.5, D0.6, D0.7\n" \
"MOV D0Ar6, #0\n" \
"LSR D1Ar5, %3, #6\n" \
"SUB TXRPT, D1Ar5, #2\n" \
"MOV RAPF, %1\n" \
"$Lloop"id":\n" \
"ADD RAPF, %1, #64\n" \
"21:\n" \
"MGETL D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"22:\n" \
"MSETL [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #32\n" \
"23:\n" \
"MGETL D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"24:\n" \
"MSETL [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #32\n" \
"DCACHE [%1+#-64], D0Ar6\n" \
"BR $Lloop"id"\n" \
\
"MOV RAPF, %1\n" \
"25:\n" \
"MGETL D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"26:\n" \
"MSETL [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #32\n" \
"27:\n" \
"MGETL D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"28:\n" \
"MSETL [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %0, %0, #8\n" \
"29:\n" \
"SETL [%0++], D0.7, D1.7\n" \
"SUB %3, %3, #32\n" \
"1:" \
"DCACHE [%1+#-64], D0Ar6\n" \
"GETL D0Ar6, D1Ar5, [A0StP+#-40]\n" \
"GETL D0FrT, D1RtP, [A0StP+#-32]\n" \
"GETL D0.5, D1.5, [A0StP+#-24]\n" \
"GETL D0.6, D1.6, [A0StP+#-16]\n" \
"GETL D0.7, D1.7, [A0StP+#-8]\n" \
"SUB A0StP, A0StP, #40\n" \
" .section .fixup,\"ax\"\n" \
"4:\n" \
" ADD %0, %0, #8\n" \
"3:\n" \
" MOV D0Ar2, TXSTATUS\n" \
" MOV D1Ar1, TXSTATUS\n" \
" AND D1Ar1, D1Ar1, #0xFFFFF8FF\n" \
" MOV TXSTATUS, D1Ar1\n" \
FIXUP \
" MOVT D0Ar2,#HI(1b)\n" \
" JUMP D0Ar2,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .long 21b,3b\n" \
" .long 22b,3b\n" \
" .long 23b,3b\n" \
" .long 24b,3b\n" \
" .long 25b,3b\n" \
" .long 26b,3b\n" \
" .long 27b,3b\n" \
" .long 28b,3b\n" \
" .long 29b,4b\n" \
" .previous\n" \
: "=r" (to), "=r" (from), "=r" (ret), "=d" (n) \
: "0" (to), "1" (from), "2" (ret), "3" (n) \
: "D1Ar1", "D0Ar2", "memory")
/* rewind 'to' and 'from' pointers when a fault occurs
*
* Rationale:
* A fault always occurs on writing to user buffer. A fault
* is at a single address, so we need to rewind by only 4
* bytes.
* Since we do a complete read from kernel buffer before
* writing, we need to rewind it also. The amount to be
* rewind equals the number of faulty writes in MSETD
* which is: [4 - (LSM_STEP-1)]*8
* LSM_STEP is bits 10:8 in TXSTATUS which is already read
* and stored in D0Ar2
*
* NOTE: If a fault occurs at the last operation in M{G,S}ETL
* LSM_STEP will be 0. ie: we do 4 writes in our case, if
* a fault happens at the 4th write, LSM_STEP will be 0
* instead of 4. The code copes with that.
*
* n is updated by the number of successful writes, which is:
* n = n - (LSM_STEP-1)*8
*/
#define __asm_copy_to_user_64bit_rapf_loop(to, from, ret, n, id)\
__asm_copy_user_64bit_rapf_loop(to, from, ret, n, id, \
"LSR D0Ar2, D0Ar2, #8\n" \
"AND D0Ar2, D0Ar2, #0x7\n" \
"ADDZ D0Ar2, D0Ar2, #4\n" \
"SUB D0Ar2, D0Ar2, #1\n" \
"MOV D1Ar1, #4\n" \
"SUB D0Ar2, D1Ar1, D0Ar2\n" \
"LSL D0Ar2, D0Ar2, #3\n" \
"LSL D1Ar1, D1Ar1, #3\n" \
"SUB D1Ar1, D1Ar1, D0Ar2\n" \
"SUB %0, %0, #8\n" \
"SUB %1, %1,D0Ar2\n" \
"SUB %3, %3, D1Ar1\n")
/*
* optimized copying loop using RAPF when 32 bit aligned
*
* n will be automatically decremented inside the loop
* ret will be left intact. if error occurs we will rewind
* so that the original non optimized code will fill up
* this value correctly.
*
* on fault:
* > n will hold total number of uncopied bytes
*
* > {'to','from'} will be rewind back so that
* the non-optimized code will do the proper fix up
*
* DCACHE drops the cacheline which helps in reducing cache
* pollution.
*
* We introduce an extra SETD at the end of the loop to
* ensure we don't fall off the loop before we catch all
* erros.
*
* NOTICE:
* LSM_STEP in TXSTATUS must be cleared in fix up code.
* since we're using M{S,G}ETL, a fault might happen at
* any address in the middle of M{S,G}ETL causing
* the value of LSM_STEP to be incorrect which can
* cause subsequent use of M{S,G}ET{L,D} to go wrong.
* ie: if LSM_STEP was 1 when a fault occurs, the
* next call to M{S,G}ET{L,D} will skip the first
* copy/getting as it think that the first 1 has already
* been done.
*
*/
#define __asm_copy_user_32bit_rapf_loop( \
to, from, ret, n, id, FIXUP) \
asm volatile ( \
".balign 8\n" \
"MOV RAPF, %1\n" \
"MSETL [A0StP++], D0Ar6, D0FrT, D0.5, D0.6, D0.7\n" \
"MOV D0Ar6, #0\n" \
"LSR D1Ar5, %3, #6\n" \
"SUB TXRPT, D1Ar5, #2\n" \
"MOV RAPF, %1\n" \
"$Lloop"id":\n" \
"ADD RAPF, %1, #64\n" \
"21:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"22:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"23:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"24:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"25:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"26:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"27:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"28:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"DCACHE [%1+#-64], D0Ar6\n" \
"BR $Lloop"id"\n" \
\
"MOV RAPF, %1\n" \
"29:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"30:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"31:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"32:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"33:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"34:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %3, %3, #16\n" \
"35:\n" \
"MGETD D0FrT, D0.5, D0.6, D0.7, [%1++]\n" \
"36:\n" \
"MSETD [%0++], D0FrT, D0.5, D0.6, D0.7\n" \
"SUB %0, %0, #4\n" \
"37:\n" \
"SETD [%0++], D0.7\n" \
"SUB %3, %3, #16\n" \
"1:" \
"DCACHE [%1+#-64], D0Ar6\n" \
"GETL D0Ar6, D1Ar5, [A0StP+#-40]\n" \
"GETL D0FrT, D1RtP, [A0StP+#-32]\n" \
"GETL D0.5, D1.5, [A0StP+#-24]\n" \
"GETL D0.6, D1.6, [A0StP+#-16]\n" \
"GETL D0.7, D1.7, [A0StP+#-8]\n" \
"SUB A0StP, A0StP, #40\n" \
" .section .fixup,\"ax\"\n" \
"4:\n" \
" ADD %0, %0, #4\n" \
"3:\n" \
" MOV D0Ar2, TXSTATUS\n" \
" MOV D1Ar1, TXSTATUS\n" \
" AND D1Ar1, D1Ar1, #0xFFFFF8FF\n" \
" MOV TXSTATUS, D1Ar1\n" \
FIXUP \
" MOVT D0Ar2,#HI(1b)\n" \
" JUMP D0Ar2,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .long 21b,3b\n" \
" .long 22b,3b\n" \
" .long 23b,3b\n" \
" .long 24b,3b\n" \
" .long 25b,3b\n" \
" .long 26b,3b\n" \
" .long 27b,3b\n" \
" .long 28b,3b\n" \
" .long 29b,3b\n" \
" .long 30b,3b\n" \
" .long 31b,3b\n" \
" .long 32b,3b\n" \
" .long 33b,3b\n" \
" .long 34b,3b\n" \
" .long 35b,3b\n" \
" .long 36b,3b\n" \
" .long 37b,4b\n" \
" .previous\n" \
: "=r" (to), "=r" (from), "=r" (ret), "=d" (n) \
: "0" (to), "1" (from), "2" (ret), "3" (n) \
: "D1Ar1", "D0Ar2", "memory")
/* rewind 'to' and 'from' pointers when a fault occurs
*
* Rationale:
* A fault always occurs on writing to user buffer. A fault
* is at a single address, so we need to rewind by only 4
* bytes.
* Since we do a complete read from kernel buffer before
* writing, we need to rewind it also. The amount to be
* rewind equals the number of faulty writes in MSETD
* which is: [4 - (LSM_STEP-1)]*4
* LSM_STEP is bits 10:8 in TXSTATUS which is already read
* and stored in D0Ar2
*
* NOTE: If a fault occurs at the last operation in M{G,S}ETL
* LSM_STEP will be 0. ie: we do 4 writes in our case, if
* a fault happens at the 4th write, LSM_STEP will be 0
* instead of 4. The code copes with that.
*
* n is updated by the number of successful writes, which is:
* n = n - (LSM_STEP-1)*4
*/
#define __asm_copy_to_user_32bit_rapf_loop(to, from, ret, n, id)\
__asm_copy_user_32bit_rapf_loop(to, from, ret, n, id, \
"LSR D0Ar2, D0Ar2, #8\n" \
"AND D0Ar2, D0Ar2, #0x7\n" \
"ADDZ D0Ar2, D0Ar2, #4\n" \
"SUB D0Ar2, D0Ar2, #1\n" \
"MOV D1Ar1, #4\n" \
"SUB D0Ar2, D1Ar1, D0Ar2\n" \
"LSL D0Ar2, D0Ar2, #2\n" \
"LSL D1Ar1, D1Ar1, #2\n" \
"SUB D1Ar1, D1Ar1, D0Ar2\n" \
"SUB %0, %0, #4\n" \
"SUB %1, %1, D0Ar2\n" \
"SUB %3, %3, D1Ar1\n")
unsigned long __copy_user(void __user *pdst, const void *psrc,
unsigned long n)
{
register char __user *dst asm ("A0.2") = pdst;
register const char *src asm ("A1.2") = psrc;
unsigned long retn = 0;
if (n == 0)
return 0;
if ((unsigned long) src & 1) {
__asm_copy_to_user_1(dst, src, retn);
n--;
}
if ((unsigned long) dst & 1) {
/* Worst case - byte copy */
while (n > 0) {
__asm_copy_to_user_1(dst, src, retn);
n--;
}
}
if (((unsigned long) src & 2) && n >= 2) {
__asm_copy_to_user_2(dst, src, retn);
n -= 2;
}
if ((unsigned long) dst & 2) {
/* Second worst case - word copy */
while (n >= 2) {
__asm_copy_to_user_2(dst, src, retn);
n -= 2;
}
}
#ifdef USE_RAPF
/* 64 bit copy loop */
if (!(((unsigned long) src | (__force unsigned long) dst) & 7)) {
if (n >= RAPF_MIN_BUF_SIZE) {
/* copy user using 64 bit rapf copy */
__asm_copy_to_user_64bit_rapf_loop(dst, src, retn,
n, "64cu");
}
while (n >= 8) {
__asm_copy_to_user_8x64(dst, src, retn);
n -= 8;
}
}
if (n >= RAPF_MIN_BUF_SIZE) {
/* copy user using 32 bit rapf copy */
__asm_copy_to_user_32bit_rapf_loop(dst, src, retn, n, "32cu");
}
#else
/* 64 bit copy loop */
if (!(((unsigned long) src | (__force unsigned long) dst) & 7)) {
while (n >= 8) {
__asm_copy_to_user_8x64(dst, src, retn);
n -= 8;
}
}
#endif
while (n >= 16) {
__asm_copy_to_user_16(dst, src, retn);
n -= 16;
}
while (n >= 4) {
__asm_copy_to_user_4(dst, src, retn);
n -= 4;
}
switch (n) {
case 0:
break;
case 1:
__asm_copy_to_user_1(dst, src, retn);
break;
case 2:
__asm_copy_to_user_2(dst, src, retn);
break;
case 3:
__asm_copy_to_user_3(dst, src, retn);
break;
}
return retn;
}
EXPORT_SYMBOL(__copy_user);
#define __asm_copy_from_user_1(to, from, ret) \
__asm_copy_user_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"2: SETB [%0++],D1Ar1\n", \
"3: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 2b,3b\n")
#define __asm_copy_from_user_2x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_user_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
"2: SETW [%0++],D1Ar1\n" COPY, \
"3: ADD %2,%2,#2\n" \
" SETW [%0++],D1Ar1\n" FIXUP, \
" .long 2b,3b\n" TENTRY)
#define __asm_copy_from_user_2(to, from, ret) \
__asm_copy_from_user_2x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_3(to, from, ret) \
__asm_copy_from_user_2x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"4: SETB [%0++],D1Ar1\n", \
"5: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 4b,5b\n")
#define __asm_copy_from_user_4x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_user_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
"2: SETD [%0++],D1Ar1\n" COPY, \
"3: ADD %2,%2,#4\n" \
" SETD [%0++],D1Ar1\n" FIXUP, \
" .long 2b,3b\n" TENTRY)
#define __asm_copy_from_user_4(to, from, ret) \
__asm_copy_from_user_4x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_5(to, from, ret) \
__asm_copy_from_user_4x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"4: SETB [%0++],D1Ar1\n", \
"5: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 4b,5b\n")
#define __asm_copy_from_user_6x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_4x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
"4: SETW [%0++],D1Ar1\n" COPY, \
"5: ADD %2,%2,#2\n" \
" SETW [%0++],D1Ar1\n" FIXUP, \
" .long 4b,5b\n" TENTRY)
#define __asm_copy_from_user_6(to, from, ret) \
__asm_copy_from_user_6x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_7(to, from, ret) \
__asm_copy_from_user_6x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"6: SETB [%0++],D1Ar1\n", \
"7: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 6b,7b\n")
#define __asm_copy_from_user_8x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_4x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
"4: SETD [%0++],D1Ar1\n" COPY, \
"5: ADD %2,%2,#4\n" \
" SETD [%0++],D1Ar1\n" FIXUP, \
" .long 4b,5b\n" TENTRY)
#define __asm_copy_from_user_8(to, from, ret) \
__asm_copy_from_user_8x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_9(to, from, ret) \
__asm_copy_from_user_8x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"6: SETB [%0++],D1Ar1\n", \
"7: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 6b,7b\n")
#define __asm_copy_from_user_10x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_8x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
"6: SETW [%0++],D1Ar1\n" COPY, \
"7: ADD %2,%2,#2\n" \
" SETW [%0++],D1Ar1\n" FIXUP, \
" .long 6b,7b\n" TENTRY)
#define __asm_copy_from_user_10(to, from, ret) \
__asm_copy_from_user_10x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_11(to, from, ret) \
__asm_copy_from_user_10x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"8: SETB [%0++],D1Ar1\n", \
"9: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 8b,9b\n")
#define __asm_copy_from_user_12x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_8x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
"6: SETD [%0++],D1Ar1\n" COPY, \
"7: ADD %2,%2,#4\n" \
" SETD [%0++],D1Ar1\n" FIXUP, \
" .long 6b,7b\n" TENTRY)
#define __asm_copy_from_user_12(to, from, ret) \
__asm_copy_from_user_12x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_13(to, from, ret) \
__asm_copy_from_user_12x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"8: SETB [%0++],D1Ar1\n", \
"9: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 8b,9b\n")
#define __asm_copy_from_user_14x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_12x_cont(to, from, ret, \
" GETW D1Ar1,[%1++]\n" \
"8: SETW [%0++],D1Ar1\n" COPY, \
"9: ADD %2,%2,#2\n" \
" SETW [%0++],D1Ar1\n" FIXUP, \
" .long 8b,9b\n" TENTRY)
#define __asm_copy_from_user_14(to, from, ret) \
__asm_copy_from_user_14x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_15(to, from, ret) \
__asm_copy_from_user_14x_cont(to, from, ret, \
" GETB D1Ar1,[%1++]\n" \
"10: SETB [%0++],D1Ar1\n", \
"11: ADD %2,%2,#1\n" \
" SETB [%0++],D1Ar1\n", \
" .long 10b,11b\n")
#define __asm_copy_from_user_16x_cont(to, from, ret, COPY, FIXUP, TENTRY) \
__asm_copy_from_user_12x_cont(to, from, ret, \
" GETD D1Ar1,[%1++]\n" \
"8: SETD [%0++],D1Ar1\n" COPY, \
"9: ADD %2,%2,#4\n" \
" SETD [%0++],D1Ar1\n" FIXUP, \
" .long 8b,9b\n" TENTRY)
#define __asm_copy_from_user_16(to, from, ret) \
__asm_copy_from_user_16x_cont(to, from, ret, "", "", "")
#define __asm_copy_from_user_8x64(to, from, ret) \
asm volatile ( \
" GETL D0Ar2,D1Ar1,[%1++]\n" \
"2: SETL [%0++],D0Ar2,D1Ar1\n" \
"1:\n" \
" .section .fixup,\"ax\"\n" \
" MOV D1Ar1,#0\n" \
" MOV D0Ar2,#0\n" \
"3: ADD %2,%2,#8\n" \
" SETL [%0++],D0Ar2,D1Ar1\n" \
" MOVT D0Ar2,#HI(1b)\n" \
" JUMP D0Ar2,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .long 2b,3b\n" \
" .previous\n" \
: "=a" (to), "=r" (from), "=r" (ret) \
: "0" (to), "1" (from), "2" (ret) \
: "D1Ar1", "D0Ar2", "memory")
/* rewind 'from' pointer when a fault occurs
*
* Rationale:
* A fault occurs while reading from user buffer, which is the
* source. Since the fault is at a single address, we only
* need to rewind by 8 bytes.
* Since we don't write to kernel buffer until we read first,
* the kernel buffer is at the right state and needn't be
* corrected.
*/
#define __asm_copy_from_user_64bit_rapf_loop(to, from, ret, n, id) \
__asm_copy_user_64bit_rapf_loop(to, from, ret, n, id, \
"SUB %1, %1, #8\n")
/* rewind 'from' pointer when a fault occurs
*
* Rationale:
* A fault occurs while reading from user buffer, which is the
* source. Since the fault is at a single address, we only
* need to rewind by 4 bytes.
* Since we don't write to kernel buffer until we read first,
* the kernel buffer is at the right state and needn't be
* corrected.
*/
#define __asm_copy_from_user_32bit_rapf_loop(to, from, ret, n, id) \
__asm_copy_user_32bit_rapf_loop(to, from, ret, n, id, \
"SUB %1, %1, #4\n")
/* Copy from user to kernel, zeroing the bytes that were inaccessible in
userland. The return-value is the number of bytes that were
inaccessible. */
unsigned long __copy_user_zeroing(void *pdst, const void __user *psrc,
unsigned long n)
{
register char *dst asm ("A0.2") = pdst;
register const char __user *src asm ("A1.2") = psrc;
unsigned long retn = 0;
if (n == 0)
return 0;
if ((unsigned long) src & 1) {
__asm_copy_from_user_1(dst, src, retn);
n--;
}
if ((unsigned long) dst & 1) {
/* Worst case - byte copy */
while (n > 0) {
__asm_copy_from_user_1(dst, src, retn);
n--;
if (retn)
goto copy_exception_bytes;
}
}
if (((unsigned long) src & 2) && n >= 2) {
__asm_copy_from_user_2(dst, src, retn);
n -= 2;
}
if ((unsigned long) dst & 2) {
/* Second worst case - word copy */
while (n >= 2) {
__asm_copy_from_user_2(dst, src, retn);
n -= 2;
if (retn)
goto copy_exception_bytes;
}
}
/* We only need one check after the unalignment-adjustments,
because if both adjustments were done, either both or
neither reference had an exception. */
if (retn != 0)
goto copy_exception_bytes;
#ifdef USE_RAPF
/* 64 bit copy loop */
if (!(((unsigned long) src | (unsigned long) dst) & 7)) {
if (n >= RAPF_MIN_BUF_SIZE) {
/* Copy using fast 64bit rapf */
__asm_copy_from_user_64bit_rapf_loop(dst, src, retn,
n, "64cuz");
}
while (n >= 8) {
__asm_copy_from_user_8x64(dst, src, retn);
n -= 8;
if (retn)
goto copy_exception_bytes;
}
}
if (n >= RAPF_MIN_BUF_SIZE) {
/* Copy using fast 32bit rapf */
__asm_copy_from_user_32bit_rapf_loop(dst, src, retn,
n, "32cuz");
}
#else
/* 64 bit copy loop */
if (!(((unsigned long) src | (unsigned long) dst) & 7)) {
while (n >= 8) {
__asm_copy_from_user_8x64(dst, src, retn);
n -= 8;
if (retn)
goto copy_exception_bytes;
}
}
#endif
while (n >= 4) {
__asm_copy_from_user_4(dst, src, retn);
n -= 4;
if (retn)
goto copy_exception_bytes;
}
/* If we get here, there were no memory read faults. */
switch (n) {
/* These copies are at least "naturally aligned" (so we don't
have to check each byte), due to the src alignment code.
The *_3 case *will* get the correct count for retn. */
case 0:
/* This case deliberately left in (if you have doubts check the
generated assembly code). */
break;
case 1:
__asm_copy_from_user_1(dst, src, retn);
break;
case 2:
__asm_copy_from_user_2(dst, src, retn);
break;
case 3:
__asm_copy_from_user_3(dst, src, retn);
break;
}
/* If we get here, retn correctly reflects the number of failing
bytes. */
return retn;
copy_exception_bytes:
/* We already have "retn" bytes cleared, and need to clear the
remaining "n" bytes. A non-optimized simple byte-for-byte in-line
memset is preferred here, since this isn't speed-critical code and
we'd rather have this a leaf-function than calling memset. */
{
char *endp;
for (endp = dst + n; dst < endp; dst++)
*dst = 0;
}
return retn + n;
}
EXPORT_SYMBOL(__copy_user_zeroing);
#define __asm_clear_8x64(to, ret) \
asm volatile ( \
" MOV D0Ar2,#0\n" \
" MOV D1Ar1,#0\n" \
" SETL [%0],D0Ar2,D1Ar1\n" \
"2: SETL [%0++],D0Ar2,D1Ar1\n" \
"1:\n" \
" .section .fixup,\"ax\"\n" \
"3: ADD %1,%1,#8\n" \
" MOVT D0Ar2,#HI(1b)\n" \
" JUMP D0Ar2,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .long 2b,3b\n" \
" .previous\n" \
: "=r" (to), "=r" (ret) \
: "0" (to), "1" (ret) \
: "D1Ar1", "D0Ar2", "memory")
/* Zero userspace. */
#define __asm_clear(to, ret, CLEAR, FIXUP, TENTRY) \
asm volatile ( \
" MOV D1Ar1,#0\n" \
CLEAR \
"1:\n" \
" .section .fixup,\"ax\"\n" \
FIXUP \
" MOVT D1Ar1,#HI(1b)\n" \
" JUMP D1Ar1,#LO(1b)\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
TENTRY \
" .previous" \
: "=r" (to), "=r" (ret) \
: "0" (to), "1" (ret) \
: "D1Ar1", "memory")
#define __asm_clear_1(to, ret) \
__asm_clear(to, ret, \
" SETB [%0],D1Ar1\n" \
"2: SETB [%0++],D1Ar1\n", \
"3: ADD %1,%1,#1\n", \
" .long 2b,3b\n")
#define __asm_clear_2(to, ret) \
__asm_clear(to, ret, \
" SETW [%0],D1Ar1\n" \
"2: SETW [%0++],D1Ar1\n", \
"3: ADD %1,%1,#2\n", \
" .long 2b,3b\n")
#define __asm_clear_3(to, ret) \
__asm_clear(to, ret, \
"2: SETW [%0++],D1Ar1\n" \
" SETB [%0],D1Ar1\n" \
"3: SETB [%0++],D1Ar1\n", \
"4: ADD %1,%1,#2\n" \
"5: ADD %1,%1,#1\n", \
" .long 2b,4b\n" \
" .long 3b,5b\n")
#define __asm_clear_4x_cont(to, ret, CLEAR, FIXUP, TENTRY) \
__asm_clear(to, ret, \
" SETD [%0],D1Ar1\n" \
"2: SETD [%0++],D1Ar1\n" CLEAR, \
"3: ADD %1,%1,#4\n" FIXUP, \
" .long 2b,3b\n" TENTRY)
#define __asm_clear_4(to, ret) \
__asm_clear_4x_cont(to, ret, "", "", "")
#define __asm_clear_8x_cont(to, ret, CLEAR, FIXUP, TENTRY) \
__asm_clear_4x_cont(to, ret, \
" SETD [%0],D1Ar1\n" \
"4: SETD [%0++],D1Ar1\n" CLEAR, \
"5: ADD %1,%1,#4\n" FIXUP, \
" .long 4b,5b\n" TENTRY)
#define __asm_clear_8(to, ret) \
__asm_clear_8x_cont(to, ret, "", "", "")
#define __asm_clear_12x_cont(to, ret, CLEAR, FIXUP, TENTRY) \
__asm_clear_8x_cont(to, ret, \
" SETD [%0],D1Ar1\n" \
"6: SETD [%0++],D1Ar1\n" CLEAR, \
"7: ADD %1,%1,#4\n" FIXUP, \
" .long 6b,7b\n" TENTRY)
#define __asm_clear_12(to, ret) \
__asm_clear_12x_cont(to, ret, "", "", "")
#define __asm_clear_16x_cont(to, ret, CLEAR, FIXUP, TENTRY) \
__asm_clear_12x_cont(to, ret, \
" SETD [%0],D1Ar1\n" \
"8: SETD [%0++],D1Ar1\n" CLEAR, \
"9: ADD %1,%1,#4\n" FIXUP, \
" .long 8b,9b\n" TENTRY)
#define __asm_clear_16(to, ret) \
__asm_clear_16x_cont(to, ret, "", "", "")
unsigned long __do_clear_user(void __user *pto, unsigned long pn)
{
register char __user *dst asm ("D0Re0") = pto;
register unsigned long n asm ("D1Re0") = pn;
register unsigned long retn asm ("D0Ar6") = 0;
if ((unsigned long) dst & 1) {
__asm_clear_1(dst, retn);
n--;
}
if ((unsigned long) dst & 2) {
__asm_clear_2(dst, retn);
n -= 2;
}
/* 64 bit copy loop */
if (!((__force unsigned long) dst & 7)) {
while (n >= 8) {
__asm_clear_8x64(dst, retn);
n -= 8;
}
}
while (n >= 16) {
__asm_clear_16(dst, retn);
n -= 16;
}
while (n >= 4) {
__asm_clear_4(dst, retn);
n -= 4;
}
switch (n) {
case 0:
break;
case 1:
__asm_clear_1(dst, retn);
break;
case 2:
__asm_clear_2(dst, retn);
break;
case 3:
__asm_clear_3(dst, retn);
break;
}
return retn;
}
EXPORT_SYMBOL(__do_clear_user);
unsigned char __get_user_asm_b(const void __user *addr, long *err)
{
register unsigned char x asm ("D0Re0") = 0;
asm volatile (
" GETB %0,[%2]\n"
"1:\n"
" GETB %0,[%2]\n"
"2:\n"
" .section .fixup,\"ax\"\n"
"3: MOV D0FrT,%3\n"
" SETD [%1],D0FrT\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .long 1b,3b\n"
" .previous\n"
: "=r" (x)
: "r" (err), "r" (addr), "P" (-EFAULT)
: "D0FrT");
return x;
}
EXPORT_SYMBOL(__get_user_asm_b);
unsigned short __get_user_asm_w(const void __user *addr, long *err)
{
register unsigned short x asm ("D0Re0") = 0;
asm volatile (
" GETW %0,[%2]\n"
"1:\n"
" GETW %0,[%2]\n"
"2:\n"
" .section .fixup,\"ax\"\n"
"3: MOV D0FrT,%3\n"
" SETD [%1],D0FrT\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .long 1b,3b\n"
" .previous\n"
: "=r" (x)
: "r" (err), "r" (addr), "P" (-EFAULT)
: "D0FrT");
return x;
}
EXPORT_SYMBOL(__get_user_asm_w);
unsigned int __get_user_asm_d(const void __user *addr, long *err)
{
register unsigned int x asm ("D0Re0") = 0;
asm volatile (
" GETD %0,[%2]\n"
"1:\n"
" GETD %0,[%2]\n"
"2:\n"
" .section .fixup,\"ax\"\n"
"3: MOV D0FrT,%3\n"
" SETD [%1],D0FrT\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .long 1b,3b\n"
" .previous\n"
: "=r" (x)
: "r" (err), "r" (addr), "P" (-EFAULT)
: "D0FrT");
return x;
}
EXPORT_SYMBOL(__get_user_asm_d);
long __put_user_asm_b(unsigned int x, void __user *addr)
{
register unsigned int err asm ("D0Re0") = 0;
asm volatile (
" MOV %0,#0\n"
" SETB [%2],%1\n"
"1:\n"
" SETB [%2],%1\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: MOV %0,%3\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .long 1b,3b\n"
".previous"
: "=r"(err)
: "d" (x), "a" (addr), "P"(-EFAULT)
: "D0FrT");
return err;
}
EXPORT_SYMBOL(__put_user_asm_b);
long __put_user_asm_w(unsigned int x, void __user *addr)
{
register unsigned int err asm ("D0Re0") = 0;
asm volatile (
" MOV %0,#0\n"
" SETW [%2],%1\n"
"1:\n"
" SETW [%2],%1\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: MOV %0,%3\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .long 1b,3b\n"
".previous"
: "=r"(err)
: "d" (x), "a" (addr), "P"(-EFAULT)
: "D0FrT");
return err;
}
EXPORT_SYMBOL(__put_user_asm_w);
long __put_user_asm_d(unsigned int x, void __user *addr)
{
register unsigned int err asm ("D0Re0") = 0;
asm volatile (
" MOV %0,#0\n"
" SETD [%2],%1\n"
"1:\n"
" SETD [%2],%1\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: MOV %0,%3\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .long 1b,3b\n"
".previous"
: "=r"(err)
: "d" (x), "a" (addr), "P"(-EFAULT)
: "D0FrT");
return err;
}
EXPORT_SYMBOL(__put_user_asm_d);
long __put_user_asm_l(unsigned long long x, void __user *addr)
{
register unsigned int err asm ("D0Re0") = 0;
asm volatile (
" MOV %0,#0\n"
" SETL [%2],%1,%t1\n"
"1:\n"
" SETL [%2],%1,%t1\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: MOV %0,%3\n"
" MOVT D0FrT,#HI(2b)\n"
" JUMP D0FrT,#LO(2b)\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .long 1b,3b\n"
".previous"
: "=r"(err)
: "d" (x), "a" (addr), "P"(-EFAULT)
: "D0FrT");
return err;
}
EXPORT_SYMBOL(__put_user_asm_l);
long strnlen_user(const char __user *src, long count)
{
long res;
if (!access_ok(VERIFY_READ, src, 0))
return 0;
asm volatile (" MOV D0Ar4, %1\n"
" MOV D0Ar6, %2\n"
"0:\n"
" SUBS D0FrT, D0Ar6, #0\n"
" SUB D0Ar6, D0Ar6, #1\n"
" BLE 2f\n"
" GETB D0FrT, [D0Ar4+#1++]\n"
"1:\n"
" TST D0FrT, #255\n"
" BNE 0b\n"
"2:\n"
" SUB %0, %2, D0Ar6\n"
"3:\n"
" .section .fixup,\"ax\"\n"
"4:\n"
" MOV %0, #0\n"
" MOVT D0FrT,#HI(3b)\n"
" JUMP D0FrT,#LO(3b)\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .long 1b,4b\n"
" .previous\n"
: "=r" (res)
: "r" (src), "r" (count)
: "D0FrT", "D0Ar4", "D0Ar6", "cc");
return res;
}
EXPORT_SYMBOL(strnlen_user);
long __strncpy_from_user(char *dst, const char __user *src, long count)
{
long res;
if (count == 0)
return 0;
/*
* Currently, in 2.4.0-test9, most ports use a simple byte-copy loop.
* So do we.
*
* This code is deduced from:
*
* char tmp2;
* long tmp1, tmp3;
* tmp1 = count;
* while ((*dst++ = (tmp2 = *src++)) != 0
* && --tmp1)
* ;
*
* res = count - tmp1;
*
* with tweaks.
*/
asm volatile (" MOV %0,%3\n"
"1:\n"
" GETB D0FrT,[%2++]\n"
"2:\n"
" CMP D0FrT,#0\n"
" SETB [%1++],D0FrT\n"
" BEQ 3f\n"
" SUBS %0,%0,#1\n"
" BNZ 1b\n"
"3:\n"
" SUB %0,%3,%0\n"
"4:\n"
" .section .fixup,\"ax\"\n"
"5:\n"
" MOV %0,%7\n"
" MOVT D0FrT,#HI(4b)\n"
" JUMP D0FrT,#LO(4b)\n"
" .previous\n"
" .section __ex_table,\"a\"\n"
" .long 2b,5b\n"
" .previous"
: "=r" (res), "=r" (dst), "=r" (src), "=r" (count)
: "3" (count), "1" (dst), "2" (src), "P" (-EFAULT)
: "D0FrT", "memory", "cc");
return res;
}
EXPORT_SYMBOL(__strncpy_from_user);