1 /******************************************************************************
2  * asm-x86/guest/hyperv-hcall.h
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms and conditions of the GNU General Public
6  * License, version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; If not, see <http://www.gnu.org/licenses/>.
15  *
16  * Copyright (c) 2019 Microsoft.
17  */
18 
19 #ifndef __X86_HYPERV_HCALL_H__
20 #define __X86_HYPERV_HCALL_H__
21 
22 #include <xen/lib.h>
23 #include <xen/types.h>
24 
25 #include <asm/asm_defns.h>
26 #include <asm/fixmap.h>
27 #include <asm/guest/hyperv-tlfs.h>
28 #include <asm/page.h>
29 
hv_do_hypercall(uint64_t control,paddr_t input_addr,paddr_t output_addr)30 static inline uint64_t hv_do_hypercall(uint64_t control, paddr_t input_addr,
31                                        paddr_t output_addr)
32 {
33     uint64_t status;
34     register unsigned long r8 asm ( "r8" ) = output_addr;
35 
36     /* See TLFS for volatile registers */
37     asm volatile ( "call hv_hcall_page"
38                    : "=a" (status), "+c" (control),
39                      "+d" (input_addr) ASM_CALL_CONSTRAINT
40                    : "r" (r8)
41                    : "memory" );
42 
43     return status;
44 }
45 
hv_do_fast_hypercall(uint16_t code,uint64_t input1,uint64_t input2)46 static inline uint64_t hv_do_fast_hypercall(uint16_t code,
47                                             uint64_t input1, uint64_t input2)
48 {
49     uint64_t status;
50     uint64_t control = code | HV_HYPERCALL_FAST_BIT;
51     register unsigned long r8 asm ( "r8" ) = input2;
52 
53     /* See TLFS for volatile registers */
54     asm volatile ( "call hv_hcall_page"
55                    : "=a" (status), "+c" (control),
56                      "+d" (input1) ASM_CALL_CONSTRAINT
57                    : "r" (r8) );
58 
59     return status;
60 }
61 
hv_do_rep_hypercall(uint16_t code,uint16_t rep_count,uint16_t varhead_size,paddr_t input,paddr_t output)62 static inline uint64_t hv_do_rep_hypercall(uint16_t code, uint16_t rep_count,
63                                            uint16_t varhead_size,
64                                            paddr_t input, paddr_t output)
65 {
66     uint64_t control = code;
67     uint64_t status;
68     uint16_t rep_comp;
69 
70     control |= (uint64_t)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
71     control |= (uint64_t)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
72 
73     do {
74         status = hv_do_hypercall(control, input, output);
75         if ( (status & HV_HYPERCALL_RESULT_MASK) != HV_STATUS_SUCCESS )
76             break;
77 
78         rep_comp = MASK_EXTR(status, HV_HYPERCALL_REP_COMP_MASK);
79 
80         control &= ~HV_HYPERCALL_REP_START_MASK;
81         control |= MASK_INSR(rep_comp, HV_HYPERCALL_REP_START_MASK);
82     } while ( rep_comp < rep_count );
83 
84     return status;
85 }
86 
87 #endif /* __X86_HYPERV_HCALL_H__ */
88 
89 /*
90  * Local variables:
91  * mode: C
92  * c-file-style: "BSD"
93  * c-basic-offset: 4
94  * tab-width: 4
95  * indent-tabs-mode: nil
96  * End:
97  */
98