Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 185 insertions, 0 deletions

diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
new file mode 100644
index 0000000000..e4a13d7cab
--- /dev/null
+++ b/arch/s390/lib/uaccess.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Standard user space access functions based on mvcp/mvcs and doing
+ *  interesting things in the secondary space mode.
+ *
+ *    Copyright IBM Corp. 2006,2014
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ *		 Gerald Schaefer (gerald.schaefer@de.ibm.com)
+ */
+
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <asm/asm-extable.h>
+
+#ifdef CONFIG_DEBUG_ENTRY
+void debug_user_asce(int exit)
+{
+	unsigned long cr1, cr7;
+
+	__ctl_store(cr1, 1, 1);
+	__ctl_store(cr7, 7, 7);
+	if (cr1 == S390_lowcore.kernel_asce && cr7 == S390_lowcore.user_asce)
+		return;
+	panic("incorrect ASCE on kernel %s\n"
+	      "cr1:    %016lx cr7:  %016lx\n"
+	      "kernel: %016llx user: %016llx\n",
+	      exit ? "exit" : "entry", cr1, cr7,
+	      S390_lowcore.kernel_asce, S390_lowcore.user_asce);
+}
+#endif /*CONFIG_DEBUG_ENTRY */
+
+static unsigned long raw_copy_from_user_key(void *to, const void __user *from,
+					    unsigned long size, unsigned long key)
+{
+	unsigned long rem;
+	union oac spec = {
+		.oac2.key = key,
+		.oac2.as = PSW_BITS_AS_SECONDARY,
+		.oac2.k = 1,
+		.oac2.a = 1,
+	};
+
+	asm volatile(
+		"	lr	0,%[spec]\n"
+		"0:	mvcos	0(%[to]),0(%[from]),%[size]\n"
+		"1:	jz	5f\n"
+		"	algr	%[size],%[val]\n"
+		"	slgr	%[from],%[val]\n"
+		"	slgr	%[to],%[val]\n"
+		"	j	0b\n"
+		"2:	la	%[rem],4095(%[from])\n"	/* rem = from + 4095 */
+		"	nr	%[rem],%[val]\n"	/* rem = (from + 4095) & -4096 */
+		"	slgr	%[rem],%[from]\n"
+		"	clgr	%[size],%[rem]\n"	/* copy crosses next page boundary? */
+		"	jnh	6f\n"
+		"3:	mvcos	0(%[to]),0(%[from]),%[rem]\n"
+		"4:	slgr	%[size],%[rem]\n"
+		"	j	6f\n"
+		"5:	slgr	%[size],%[size]\n"
+		"6:\n"
+		EX_TABLE(0b, 2b)
+		EX_TABLE(1b, 2b)
+		EX_TABLE(3b, 6b)
+		EX_TABLE(4b, 6b)
+		: [size] "+&a" (size), [from] "+&a" (from), [to] "+&a" (to), [rem] "=&a" (rem)
+		: [val] "a" (-4096UL), [spec] "d" (spec.val)
+		: "cc", "memory", "0");
+	return size;
+}
+
+unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	return raw_copy_from_user_key(to, from, n, 0);
+}
+EXPORT_SYMBOL(raw_copy_from_user);
+
+unsigned long _copy_from_user_key(void *to, const void __user *from,
+				  unsigned long n, unsigned long key)
+{
+	unsigned long res = n;
+
+	might_fault();
+	if (!should_fail_usercopy()) {
+		instrument_copy_from_user_before(to, from, n);
+		res = raw_copy_from_user_key(to, from, n, key);
+		instrument_copy_from_user_after(to, from, n, res);
+	}
+	if (unlikely(res))
+		memset(to + (n - res), 0, res);
+	return res;
+}
+EXPORT_SYMBOL(_copy_from_user_key);
+
+static unsigned long raw_copy_to_user_key(void __user *to, const void *from,
+					  unsigned long size, unsigned long key)
+{
+	unsigned long rem;
+	union oac spec = {
+		.oac1.key = key,
+		.oac1.as = PSW_BITS_AS_SECONDARY,
+		.oac1.k = 1,
+		.oac1.a = 1,
+	};
+
+	asm volatile(
+		"	lr	0,%[spec]\n"
+		"0:	mvcos	0(%[to]),0(%[from]),%[size]\n"
+		"1:	jz	5f\n"
+		"	algr	%[size],%[val]\n"
+		"	slgr	%[to],%[val]\n"
+		"	slgr	%[from],%[val]\n"
+		"	j	0b\n"
+		"2:	la	%[rem],4095(%[to])\n"	/* rem = to + 4095 */
+		"	nr	%[rem],%[val]\n"	/* rem = (to + 4095) & -4096 */
+		"	slgr	%[rem],%[to]\n"
+		"	clgr	%[size],%[rem]\n"	/* copy crosses next page boundary? */
+		"	jnh	6f\n"
+		"3:	mvcos	0(%[to]),0(%[from]),%[rem]\n"
+		"4:	slgr	%[size],%[rem]\n"
+		"	j	6f\n"
+		"5:	slgr	%[size],%[size]\n"
+		"6:\n"
+		EX_TABLE(0b, 2b)
+		EX_TABLE(1b, 2b)
+		EX_TABLE(3b, 6b)
+		EX_TABLE(4b, 6b)
+		: [size] "+&a" (size), [to] "+&a" (to), [from] "+&a" (from), [rem] "=&a" (rem)
+		: [val] "a" (-4096UL), [spec] "d" (spec.val)
+		: "cc", "memory", "0");
+	return size;
+}
+
+unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	return raw_copy_to_user_key(to, from, n, 0);
+}
+EXPORT_SYMBOL(raw_copy_to_user);
+
+unsigned long _copy_to_user_key(void __user *to, const void *from,
+				unsigned long n, unsigned long key)
+{
+	might_fault();
+	if (should_fail_usercopy())
+		return n;
+	instrument_copy_to_user(to, from, n);
+	return raw_copy_to_user_key(to, from, n, key);
+}
+EXPORT_SYMBOL(_copy_to_user_key);
+
+unsigned long __clear_user(void __user *to, unsigned long size)
+{
+	unsigned long rem;
+	union oac spec = {
+		.oac1.as = PSW_BITS_AS_SECONDARY,
+		.oac1.a = 1,
+	};
+
+	asm volatile(
+		"	lr	0,%[spec]\n"
+		"0:	mvcos	0(%[to]),0(%[zeropg]),%[size]\n"
+		"1:	jz	5f\n"
+		"	algr	%[size],%[val]\n"
+		"	slgr	%[to],%[val]\n"
+		"	j	0b\n"
+		"2:	la	%[rem],4095(%[to])\n"	/* rem = to + 4095 */
+		"	nr	%[rem],%[val]\n"	/* rem = (to + 4095) & -4096 */
+		"	slgr	%[rem],%[to]\n"
+		"	clgr	%[size],%[rem]\n"	/* copy crosses next page boundary? */
+		"	jnh	6f\n"
+		"3:	mvcos	0(%[to]),0(%[zeropg]),%[rem]\n"
+		"4:	slgr	%[size],%[rem]\n"
+		"	j	6f\n"
+		"5:	slgr	%[size],%[size]\n"
+		"6:\n"
+		EX_TABLE(0b, 2b)
+		EX_TABLE(1b, 2b)
+		EX_TABLE(3b, 6b)
+		EX_TABLE(4b, 6b)
+		: [size] "+&a" (size), [to] "+&a" (to), [rem] "=&a" (rem)
+		: [val] "a" (-4096UL), [zeropg] "a" (empty_zero_page), [spec] "d" (spec.val)
+		: "cc", "memory", "0");
+	return size;
+}
+EXPORT_SYMBOL(__clear_user);