forked from Minki/linux
5a79859ae0
Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.
The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.
Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
393 lines
10 KiB
C
393 lines
10 KiB
C
/*
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* Standard user space access functions based on mvcp/mvcs and doing
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* interesting things in the secondary space mode.
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*
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* Copyright IBM Corp. 2006,2014
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* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
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* Gerald Schaefer (gerald.schaefer@de.ibm.com)
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*/
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#include <linux/jump_label.h>
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#include <linux/uaccess.h>
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#include <linux/export.h>
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#include <linux/errno.h>
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#include <linux/mm.h>
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#include <asm/mmu_context.h>
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#include <asm/facility.h>
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static struct static_key have_mvcos = STATIC_KEY_INIT_FALSE;
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static inline unsigned long copy_from_user_mvcos(void *x, const void __user *ptr,
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unsigned long size)
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{
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register unsigned long reg0 asm("0") = 0x81UL;
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unsigned long tmp1, tmp2;
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tmp1 = -4096UL;
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asm volatile(
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"0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n"
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"9: jz 7f\n"
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"1: algr %0,%3\n"
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" slgr %1,%3\n"
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" slgr %2,%3\n"
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" j 0b\n"
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"2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
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" nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
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" slgr %4,%1\n"
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" clgr %0,%4\n" /* copy crosses next page boundary? */
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" jnh 4f\n"
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"3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n"
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"10:slgr %0,%4\n"
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" algr %2,%4\n"
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"4: lghi %4,-1\n"
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" algr %4,%0\n" /* copy remaining size, subtract 1 */
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" bras %3,6f\n" /* memset loop */
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" xc 0(1,%2),0(%2)\n"
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"5: xc 0(256,%2),0(%2)\n"
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" la %2,256(%2)\n"
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"6: aghi %4,-256\n"
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" jnm 5b\n"
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" ex %4,0(%3)\n"
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" j 8f\n"
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"7:slgr %0,%0\n"
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"8:\n"
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EX_TABLE(0b,2b) EX_TABLE(3b,4b) EX_TABLE(9b,2b) EX_TABLE(10b,4b)
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: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
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: "d" (reg0) : "cc", "memory");
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return size;
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}
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static inline unsigned long copy_from_user_mvcp(void *x, const void __user *ptr,
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unsigned long size)
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{
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unsigned long tmp1, tmp2;
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load_kernel_asce();
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tmp1 = -256UL;
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asm volatile(
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" sacf 0\n"
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"0: mvcp 0(%0,%2),0(%1),%3\n"
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"10:jz 8f\n"
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"1: algr %0,%3\n"
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" la %1,256(%1)\n"
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" la %2,256(%2)\n"
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"2: mvcp 0(%0,%2),0(%1),%3\n"
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"11:jnz 1b\n"
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" j 8f\n"
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"3: la %4,255(%1)\n" /* %4 = ptr + 255 */
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" lghi %3,-4096\n"
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" nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */
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" slgr %4,%1\n"
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" clgr %0,%4\n" /* copy crosses next page boundary? */
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" jnh 5f\n"
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"4: mvcp 0(%4,%2),0(%1),%3\n"
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"12:slgr %0,%4\n"
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" algr %2,%4\n"
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"5: lghi %4,-1\n"
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" algr %4,%0\n" /* copy remaining size, subtract 1 */
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" bras %3,7f\n" /* memset loop */
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" xc 0(1,%2),0(%2)\n"
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"6: xc 0(256,%2),0(%2)\n"
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" la %2,256(%2)\n"
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"7: aghi %4,-256\n"
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" jnm 6b\n"
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" ex %4,0(%3)\n"
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" j 9f\n"
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"8:slgr %0,%0\n"
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"9: sacf 768\n"
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EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,5b)
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EX_TABLE(10b,3b) EX_TABLE(11b,3b) EX_TABLE(12b,5b)
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: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
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: : "cc", "memory");
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return size;
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}
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unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n)
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{
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if (static_key_false(&have_mvcos))
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return copy_from_user_mvcos(to, from, n);
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return copy_from_user_mvcp(to, from, n);
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}
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EXPORT_SYMBOL(__copy_from_user);
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static inline unsigned long copy_to_user_mvcos(void __user *ptr, const void *x,
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unsigned long size)
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{
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register unsigned long reg0 asm("0") = 0x810000UL;
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unsigned long tmp1, tmp2;
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tmp1 = -4096UL;
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asm volatile(
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"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
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"6: jz 4f\n"
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"1: algr %0,%3\n"
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" slgr %1,%3\n"
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" slgr %2,%3\n"
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" j 0b\n"
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"2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
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" nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
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" slgr %4,%1\n"
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" clgr %0,%4\n" /* copy crosses next page boundary? */
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" jnh 5f\n"
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"3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n"
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"7: slgr %0,%4\n"
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" j 5f\n"
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"4: slgr %0,%0\n"
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"5:\n"
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EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
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: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
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: "d" (reg0) : "cc", "memory");
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return size;
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}
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static inline unsigned long copy_to_user_mvcs(void __user *ptr, const void *x,
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unsigned long size)
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{
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unsigned long tmp1, tmp2;
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load_kernel_asce();
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tmp1 = -256UL;
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asm volatile(
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" sacf 0\n"
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"0: mvcs 0(%0,%1),0(%2),%3\n"
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"7: jz 5f\n"
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"1: algr %0,%3\n"
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" la %1,256(%1)\n"
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" la %2,256(%2)\n"
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"2: mvcs 0(%0,%1),0(%2),%3\n"
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"8: jnz 1b\n"
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" j 5f\n"
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"3: la %4,255(%1)\n" /* %4 = ptr + 255 */
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" lghi %3,-4096\n"
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" nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */
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" slgr %4,%1\n"
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" clgr %0,%4\n" /* copy crosses next page boundary? */
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" jnh 6f\n"
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"4: mvcs 0(%4,%1),0(%2),%3\n"
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"9: slgr %0,%4\n"
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" j 6f\n"
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"5: slgr %0,%0\n"
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"6: sacf 768\n"
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EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
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EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
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: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
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: : "cc", "memory");
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return size;
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}
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unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n)
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{
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if (static_key_false(&have_mvcos))
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return copy_to_user_mvcos(to, from, n);
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return copy_to_user_mvcs(to, from, n);
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}
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EXPORT_SYMBOL(__copy_to_user);
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static inline unsigned long copy_in_user_mvcos(void __user *to, const void __user *from,
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unsigned long size)
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{
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register unsigned long reg0 asm("0") = 0x810081UL;
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unsigned long tmp1, tmp2;
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tmp1 = -4096UL;
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/* FIXME: copy with reduced length. */
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asm volatile(
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"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
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" jz 2f\n"
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"1: algr %0,%3\n"
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" slgr %1,%3\n"
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" slgr %2,%3\n"
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" j 0b\n"
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"2:slgr %0,%0\n"
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"3: \n"
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EX_TABLE(0b,3b)
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: "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
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: "d" (reg0) : "cc", "memory");
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return size;
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}
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static inline unsigned long copy_in_user_mvc(void __user *to, const void __user *from,
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unsigned long size)
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{
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unsigned long tmp1;
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load_kernel_asce();
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asm volatile(
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" sacf 256\n"
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" aghi %0,-1\n"
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" jo 5f\n"
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" bras %3,3f\n"
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"0: aghi %0,257\n"
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"1: mvc 0(1,%1),0(%2)\n"
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" la %1,1(%1)\n"
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" la %2,1(%2)\n"
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" aghi %0,-1\n"
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" jnz 1b\n"
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" j 5f\n"
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"2: mvc 0(256,%1),0(%2)\n"
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" la %1,256(%1)\n"
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" la %2,256(%2)\n"
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"3: aghi %0,-256\n"
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" jnm 2b\n"
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"4: ex %0,1b-0b(%3)\n"
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"5: slgr %0,%0\n"
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"6: sacf 768\n"
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EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
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: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
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: : "cc", "memory");
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return size;
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}
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unsigned long __copy_in_user(void __user *to, const void __user *from, unsigned long n)
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{
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if (static_key_false(&have_mvcos))
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return copy_in_user_mvcos(to, from, n);
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return copy_in_user_mvc(to, from, n);
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}
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EXPORT_SYMBOL(__copy_in_user);
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static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size)
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{
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register unsigned long reg0 asm("0") = 0x810000UL;
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unsigned long tmp1, tmp2;
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tmp1 = -4096UL;
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asm volatile(
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"0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
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" jz 4f\n"
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"1: algr %0,%2\n"
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" slgr %1,%2\n"
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" j 0b\n"
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"2: la %3,4095(%1)\n"/* %4 = to + 4095 */
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" nr %3,%2\n" /* %4 = (to + 4095) & -4096 */
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" slgr %3,%1\n"
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" clgr %0,%3\n" /* copy crosses next page boundary? */
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" jnh 5f\n"
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"3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n"
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" slgr %0,%3\n"
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" j 5f\n"
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"4:slgr %0,%0\n"
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"5:\n"
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EX_TABLE(0b,2b) EX_TABLE(3b,5b)
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: "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2)
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: "a" (empty_zero_page), "d" (reg0) : "cc", "memory");
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return size;
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}
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static inline unsigned long clear_user_xc(void __user *to, unsigned long size)
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{
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unsigned long tmp1, tmp2;
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load_kernel_asce();
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asm volatile(
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" sacf 256\n"
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" aghi %0,-1\n"
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" jo 5f\n"
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" bras %3,3f\n"
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" xc 0(1,%1),0(%1)\n"
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"0: aghi %0,257\n"
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" la %2,255(%1)\n" /* %2 = ptr + 255 */
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" srl %2,12\n"
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" sll %2,12\n" /* %2 = (ptr + 255) & -4096 */
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" slgr %2,%1\n"
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" clgr %0,%2\n" /* clear crosses next page boundary? */
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" jnh 5f\n"
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" aghi %2,-1\n"
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"1: ex %2,0(%3)\n"
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" aghi %2,1\n"
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" slgr %0,%2\n"
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" j 5f\n"
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"2: xc 0(256,%1),0(%1)\n"
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" la %1,256(%1)\n"
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"3: aghi %0,-256\n"
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" jnm 2b\n"
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"4: ex %0,0(%3)\n"
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"5: slgr %0,%0\n"
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"6: sacf 768\n"
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EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
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: "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
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: : "cc", "memory");
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return size;
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}
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unsigned long __clear_user(void __user *to, unsigned long size)
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{
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if (static_key_false(&have_mvcos))
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return clear_user_mvcos(to, size);
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return clear_user_xc(to, size);
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}
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EXPORT_SYMBOL(__clear_user);
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static inline unsigned long strnlen_user_srst(const char __user *src,
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unsigned long size)
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{
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register unsigned long reg0 asm("0") = 0;
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unsigned long tmp1, tmp2;
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asm volatile(
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" la %2,0(%1)\n"
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" la %3,0(%0,%1)\n"
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" slgr %0,%0\n"
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" sacf 256\n"
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"0: srst %3,%2\n"
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" jo 0b\n"
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" la %0,1(%3)\n" /* strnlen_user results includes \0 */
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" slgr %0,%1\n"
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"1: sacf 768\n"
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EX_TABLE(0b,1b)
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: "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2)
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: "d" (reg0) : "cc", "memory");
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return size;
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}
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unsigned long __strnlen_user(const char __user *src, unsigned long size)
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{
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if (unlikely(!size))
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return 0;
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load_kernel_asce();
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return strnlen_user_srst(src, size);
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}
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EXPORT_SYMBOL(__strnlen_user);
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long __strncpy_from_user(char *dst, const char __user *src, long size)
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{
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size_t done, len, offset, len_str;
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if (unlikely(size <= 0))
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return 0;
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done = 0;
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do {
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offset = (size_t)src & ~PAGE_MASK;
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len = min(size - done, PAGE_SIZE - offset);
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if (copy_from_user(dst, src, len))
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return -EFAULT;
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len_str = strnlen(dst, len);
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done += len_str;
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src += len_str;
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dst += len_str;
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} while ((len_str == len) && (done < size));
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return done;
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}
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EXPORT_SYMBOL(__strncpy_from_user);
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/*
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* The "old" uaccess variant without mvcos can be enforced with the
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* uaccess_primary kernel parameter. This is mainly for debugging purposes.
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*/
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static int uaccess_primary __initdata;
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static int __init parse_uaccess_pt(char *__unused)
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{
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uaccess_primary = 1;
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return 0;
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}
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early_param("uaccess_primary", parse_uaccess_pt);
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static int __init uaccess_init(void)
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{
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if (!uaccess_primary && test_facility(27))
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static_key_slow_inc(&have_mvcos);
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return 0;
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}
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early_initcall(uaccess_init);
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