xref: /linux/arch/s390/boot/uv.c (revision 08f3e0873ac203449465c2b8473d684e2f9f41d1)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <asm/uv.h>
3 #include <asm/boot_data.h>
4 #include <asm/facility.h>
5 #include <asm/sections.h>
6 
7 #include "boot.h"
8 #include "uv.h"
9 
10 /* will be used in arch/s390/kernel/uv.c */
11 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
12 int __bootdata_preserved(prot_virt_guest);
13 #endif
14 #if IS_ENABLED(CONFIG_KVM)
15 int __bootdata_preserved(prot_virt_host);
16 #endif
17 struct uv_info __bootdata_preserved(uv_info);
18 
19 void uv_query_info(void)
20 {
21 	struct uv_cb_qui uvcb = {
22 		.header.cmd = UVC_CMD_QUI,
23 		.header.len = sizeof(uvcb)
24 	};
25 
26 	if (!test_facility(158))
27 		return;
28 
29 	/* rc==0x100 means that there is additional data we do not process */
30 	if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100)
31 		return;
32 
33 	if (IS_ENABLED(CONFIG_KVM)) {
34 		memcpy(uv_info.inst_calls_list, uvcb.inst_calls_list, sizeof(uv_info.inst_calls_list));
35 		uv_info.uv_base_stor_len = uvcb.uv_base_stor_len;
36 		uv_info.guest_base_stor_len = uvcb.conf_base_phys_stor_len;
37 		uv_info.guest_virt_base_stor_len = uvcb.conf_base_virt_stor_len;
38 		uv_info.guest_virt_var_stor_len = uvcb.conf_virt_var_stor_len;
39 		uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
40 		uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
41 		uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
42 		uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
43 		uv_info.uv_feature_indications = uvcb.uv_feature_indications;
44 	}
45 
46 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
47 	if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) &&
48 	    test_bit_inv(BIT_UVC_CMD_REMOVE_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list))
49 		prot_virt_guest = 1;
50 #endif
51 }
52 
53 #if IS_ENABLED(CONFIG_KVM)
54 void adjust_to_uv_max(unsigned long *vmax)
55 {
56 	if (is_prot_virt_host() && uv_info.max_sec_stor_addr)
57 		*vmax = min_t(unsigned long, *vmax, uv_info.max_sec_stor_addr);
58 }
59 
60 static int is_prot_virt_host_capable(void)
61 {
62 	/* disable if no prot_virt=1 given on command-line */
63 	if (!is_prot_virt_host())
64 		return 0;
65 	/* disable if protected guest virtualization is enabled */
66 	if (is_prot_virt_guest())
67 		return 0;
68 	/* disable if no hardware support */
69 	if (!test_facility(158))
70 		return 0;
71 	/* disable if kdump */
72 	if (oldmem_data.start)
73 		return 0;
74 	/* disable if stand-alone dump */
75 	if (ipl_block_valid && is_ipl_block_dump())
76 		return 0;
77 	return 1;
78 }
79 
80 void sanitize_prot_virt_host(void)
81 {
82 	prot_virt_host = is_prot_virt_host_capable();
83 }
84 #endif
85