[S390] Improve address space mode selection.
Introduce user_mode to replace the two variables switch_amode and
s390_noexec. There are three valid combinations of the old values:
1) switch_amode == 0 && s390_noexec == 0
2) switch_amode == 1 && s390_noexec == 0
3) switch_amode == 1 && s390_noexec == 1
They get replaced by
1) user_mode == HOME_SPACE_MODE
2) user_mode == PRIMARY_SPACE_MODE
3) user_mode == SECONDARY_SPACE_MODE
The new kernel parameter user_mode=[primary,secondary,home] lets
you choose the address space mode the user space processes should
use. In addition the CONFIG_S390_SWITCH_AMODE config option
is removed.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 061479f..0663287 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -305,9 +305,8 @@
}
early_param("mem", early_parse_mem);
-#ifdef CONFIG_S390_SWITCH_AMODE
-unsigned int switch_amode = 0;
-EXPORT_SYMBOL_GPL(switch_amode);
+unsigned int user_mode = HOME_SPACE_MODE;
+EXPORT_SYMBOL_GPL(user_mode);
static int set_amode_and_uaccess(unsigned long user_amode,
unsigned long user32_amode)
@@ -340,23 +339,29 @@
*/
static int __init early_parse_switch_amode(char *p)
{
- switch_amode = 1;
+ if (user_mode != SECONDARY_SPACE_MODE)
+ user_mode = PRIMARY_SPACE_MODE;
return 0;
}
early_param("switch_amode", early_parse_switch_amode);
-#else /* CONFIG_S390_SWITCH_AMODE */
-static inline int set_amode_and_uaccess(unsigned long user_amode,
- unsigned long user32_amode)
+static int __init early_parse_user_mode(char *p)
{
+ if (p && strcmp(p, "primary") == 0)
+ user_mode = PRIMARY_SPACE_MODE;
+#ifdef CONFIG_S390_EXEC_PROTECT
+ else if (p && strcmp(p, "secondary") == 0)
+ user_mode = SECONDARY_SPACE_MODE;
+#endif
+ else if (!p || strcmp(p, "home") == 0)
+ user_mode = HOME_SPACE_MODE;
+ else
+ return 1;
return 0;
}
-#endif /* CONFIG_S390_SWITCH_AMODE */
+early_param("user_mode", early_parse_user_mode);
#ifdef CONFIG_S390_EXEC_PROTECT
-unsigned int s390_noexec = 0;
-EXPORT_SYMBOL_GPL(s390_noexec);
-
/*
* Enable execute protection?
*/
@@ -364,8 +369,7 @@
{
if (!strncmp(p, "off", 3))
return 0;
- switch_amode = 1;
- s390_noexec = 1;
+ user_mode = SECONDARY_SPACE_MODE;
return 0;
}
early_param("noexec", early_parse_noexec);
@@ -373,7 +377,7 @@
static void setup_addressing_mode(void)
{
- if (s390_noexec) {
+ if (user_mode == SECONDARY_SPACE_MODE) {
if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
PSW32_ASC_SECONDARY))
pr_info("Execute protection active, "
@@ -381,7 +385,7 @@
else
pr_info("Execute protection active, "
"mvcos not available\n");
- } else if (switch_amode) {
+ } else if (user_mode == PRIMARY_SPACE_MODE) {
if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
pr_info("Address spaces switched, "
"mvcos available\n");
@@ -411,7 +415,7 @@
lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
lc->restart_psw.addr =
PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
- if (switch_amode)
+ if (user_mode != HOME_SPACE_MODE)
lc->restart_psw.mask |= PSW_ASC_HOME;
lc->external_new_psw.mask = psw_kernel_bits;
lc->external_new_psw.addr =
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index adfb32a..5f99e66 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -86,7 +86,8 @@
unsigned int facility_list;
facility_list = stfl();
- vd->ectg_available = switch_amode && (facility_list & 1);
+ vd->ectg_available =
+ user_mode != HOME_SPACE_MODE && (facility_list & 1);
}
#ifdef CONFIG_64BIT
@@ -114,7 +115,7 @@
lowcore->vdso_per_cpu_data = __LC_PASTE;
- if (!switch_amode || !vdso_enabled)
+ if (user_mode == HOME_SPACE_MODE || !vdso_enabled)
return 0;
segment_table = __get_free_pages(GFP_KERNEL, SEGMENT_ORDER);
@@ -160,7 +161,7 @@
unsigned long segment_table, page_table, page_frame;
u32 *psal, *aste;
- if (!switch_amode || !vdso_enabled)
+ if (user_mode == HOME_SPACE_MODE || !vdso_enabled)
return;
psal = (u32 *)(addr_t) lowcore->paste[4];
@@ -184,7 +185,7 @@
static void vdso_init_cr5(void)
{
- if (switch_amode && vdso_enabled)
+ if (user_mode != HOME_SPACE_MODE && vdso_enabled)
on_each_cpu(__vdso_init_cr5, NULL, 1);
}
#endif /* CONFIG_64BIT */