linux/arch/s390/boot/uv.c
Vasily Gorbik 0c4f2623b9 s390: setup kernel memory layout early
Currently there are two separate places where kernel memory layout has
to be known and adjusted:
1. early kasan setup.
2. paging setup later.

Those 2 places had to be kept in sync and adjusted to reflect peculiar
technical details of one another. With additional factors which influence
kernel memory layout like ultravisor secure storage limit, complexity
of keeping two things in sync grew up even more.

Besides that if we look forward towards creating identity mapping and
enabling DAT before jumping into uncompressed kernel - that would also
require full knowledge of and control over kernel memory layout.

So, de-duplicate and move kernel memory layout setup logic into
the decompressor.

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-18 16:41:19 +02:00

72 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <asm/uv.h>
#include <asm/facility.h>
#include <asm/sections.h>
/* will be used in arch/s390/kernel/uv.c */
#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
int __bootdata_preserved(prot_virt_guest);
#endif
#if IS_ENABLED(CONFIG_KVM)
int __bootdata_preserved(prot_virt_host);
#endif
struct uv_info __bootdata_preserved(uv_info);
void uv_query_info(void)
{
struct uv_cb_qui uvcb = {
.header.cmd = UVC_CMD_QUI,
.header.len = sizeof(uvcb)
};
if (!test_facility(158))
return;
/* rc==0x100 means that there is additional data we do not process */
if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100)
return;
if (IS_ENABLED(CONFIG_KVM)) {
memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list));
uv_info.uv_base_stor_len = uvcb.uv_base_stor_len;
uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len;
uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len;
uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len;
uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
}
#ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) &&
test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list))
prot_virt_guest = 1;
#endif
}
#if IS_ENABLED(CONFIG_KVM)
static bool has_uv_sec_stor_limit(void)
{
/*
* keep these conditions in line with setup_uv()
*/
if (!is_prot_virt_host())
return false;
if (is_prot_virt_guest())
return false;
if (!test_facility(158))
return false;
return !!uv_info.max_sec_stor_addr;
}
void adjust_to_uv_max(unsigned long *vmax)
{
if (has_uv_sec_stor_limit())
*vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
}
#endif