xref: /openbmc/linux/arch/s390/boot/uv.c (revision a3cbcadf)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <asm/uv.h>
3 #include <asm/facility.h>
4 #include <asm/sections.h>
5 
6 /* will be used in arch/s390/kernel/uv.c */
7 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
8 int __bootdata_preserved(prot_virt_guest);
9 #endif
10 #if IS_ENABLED(CONFIG_KVM)
11 int __bootdata_preserved(prot_virt_host);
12 #endif
13 struct uv_info __bootdata_preserved(uv_info);
14 
15 void uv_query_info(void)
16 {
17 	struct uv_cb_qui uvcb = {
18 		.header.cmd = UVC_CMD_QUI,
19 		.header.len = sizeof(uvcb)
20 	};
21 
22 	if (!test_facility(158))
23 		return;
24 
25 	/* rc==0x100 means that there is additional data we do not process */
26 	if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100)
27 		return;
28 
29 	if (IS_ENABLED(CONFIG_KVM)) {
30 		memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list));
31 		uv_info.uv_base_stor_len = uvcb.uv_base_stor_len;
32 		uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len;
33 		uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len;
34 		uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len;
35 		uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
36 		uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
37 		uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
38 		uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
39 	}
40 
41 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
42 	if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) &&
43 	    test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list))
44 		prot_virt_guest = 1;
45 #endif
46 }
47 
48 #if IS_ENABLED(CONFIG_KVM)
49 static bool has_uv_sec_stor_limit(void)
50 {
51 	/*
52 	 * keep these conditions in line with setup_uv()
53 	 */
54 	if (!is_prot_virt_host())
55 		return false;
56 
57 	if (is_prot_virt_guest())
58 		return false;
59 
60 	if (!test_facility(158))
61 		return false;
62 
63 	return !!uv_info.max_sec_stor_addr;
64 }
65 
66 void adjust_to_uv_max(unsigned long *vmax)
67 {
68 	if (has_uv_sec_stor_limit())
69 		*vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
70 }
71 #endif
72