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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * S390 version
4 * Copyright IBM Corp. 1999, 2007
5 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
6 * Christian Borntraeger (cborntra@de.ibm.com),
7 */
8
9#define KMSG_COMPONENT "cpcmd"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/export.h>
14#include <linux/slab.h>
15#include <linux/spinlock.h>
16#include <linux/stddef.h>
17#include <linux/string.h>
18#include <linux/mm.h>
19#include <asm/diag.h>
20#include <asm/ebcdic.h>
21#include <asm/cpcmd.h>
22#include <asm/io.h>
23
24static DEFINE_SPINLOCK(cpcmd_lock);
25static char cpcmd_buf[241];
26
27static int diag8_noresponse(int cmdlen)
28{
29 register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
30 register unsigned long reg3 asm ("3") = cmdlen;
31
32 asm volatile(
33 " diag %1,%0,0x8\n"
34 : "+d" (reg3) : "d" (reg2) : "cc");
35 return reg3;
36}
37
38static int diag8_response(int cmdlen, char *response, int *rlen)
39{
40 register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
41 register unsigned long reg3 asm ("3") = (addr_t) response;
42 register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L;
43 register unsigned long reg5 asm ("5") = *rlen;
44
45 asm volatile(
46 " diag %2,%0,0x8\n"
47 " brc 8,1f\n"
48 " agr %1,%4\n"
49 "1:\n"
50 : "+d" (reg4), "+d" (reg5)
51 : "d" (reg2), "d" (reg3), "d" (*rlen) : "cc");
52 *rlen = reg5;
53 return reg4;
54}
55
56/*
57 * __cpcmd has some restrictions over cpcmd
58 * - __cpcmd is unlocked and therefore not SMP-safe
59 */
60int __cpcmd(const char *cmd, char *response, int rlen, int *response_code)
61{
62 int cmdlen;
63 int rc;
64 int response_len;
65
66 cmdlen = strlen(cmd);
67 BUG_ON(cmdlen > 240);
68 memcpy(cpcmd_buf, cmd, cmdlen);
69 ASCEBC(cpcmd_buf, cmdlen);
70
71 diag_stat_inc(DIAG_STAT_X008);
72 if (response) {
73 memset(response, 0, rlen);
74 response_len = rlen;
75 rc = diag8_response(cmdlen, response, &rlen);
76 EBCASC(response, response_len);
77 } else {
78 rc = diag8_noresponse(cmdlen);
79 }
80 if (response_code)
81 *response_code = rc;
82 return rlen;
83}
84EXPORT_SYMBOL(__cpcmd);
85
86int cpcmd(const char *cmd, char *response, int rlen, int *response_code)
87{
88 unsigned long flags;
89 char *lowbuf;
90 int len;
91
92 if (is_vmalloc_or_module_addr(response)) {
93 lowbuf = kmalloc(rlen, GFP_KERNEL);
94 if (!lowbuf) {
95 pr_warn("The cpcmd kernel function failed to allocate a response buffer\n");
96 return -ENOMEM;
97 }
98 spin_lock_irqsave(&cpcmd_lock, flags);
99 len = __cpcmd(cmd, lowbuf, rlen, response_code);
100 spin_unlock_irqrestore(&cpcmd_lock, flags);
101 memcpy(response, lowbuf, rlen);
102 kfree(lowbuf);
103 } else {
104 spin_lock_irqsave(&cpcmd_lock, flags);
105 len = __cpcmd(cmd, response, rlen, response_code);
106 spin_unlock_irqrestore(&cpcmd_lock, flags);
107 }
108 return len;
109}
110EXPORT_SYMBOL(cpcmd);
1/*
2 * arch/s390/kernel/cpcmd.c
3 *
4 * S390 version
5 * Copyright IBM Corp. 1999,2007
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7 * Christian Borntraeger (cborntra@de.ibm.com),
8 */
9
10#define KMSG_COMPONENT "cpcmd"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/spinlock.h>
17#include <linux/stddef.h>
18#include <linux/string.h>
19#include <asm/ebcdic.h>
20#include <asm/cpcmd.h>
21#include <asm/system.h>
22#include <asm/io.h>
23
24static DEFINE_SPINLOCK(cpcmd_lock);
25static char cpcmd_buf[241];
26
27static int diag8_noresponse(int cmdlen)
28{
29 register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
30 register unsigned long reg3 asm ("3") = cmdlen;
31
32 asm volatile(
33#ifndef CONFIG_64BIT
34 " diag %1,%0,0x8\n"
35#else /* CONFIG_64BIT */
36 " sam31\n"
37 " diag %1,%0,0x8\n"
38 " sam64\n"
39#endif /* CONFIG_64BIT */
40 : "+d" (reg3) : "d" (reg2) : "cc");
41 return reg3;
42}
43
44static int diag8_response(int cmdlen, char *response, int *rlen)
45{
46 register unsigned long reg2 asm ("2") = (addr_t) cpcmd_buf;
47 register unsigned long reg3 asm ("3") = (addr_t) response;
48 register unsigned long reg4 asm ("4") = cmdlen | 0x40000000L;
49 register unsigned long reg5 asm ("5") = *rlen;
50
51 asm volatile(
52#ifndef CONFIG_64BIT
53 " diag %2,%0,0x8\n"
54 " brc 8,1f\n"
55 " ar %1,%4\n"
56#else /* CONFIG_64BIT */
57 " sam31\n"
58 " diag %2,%0,0x8\n"
59 " sam64\n"
60 " brc 8,1f\n"
61 " agr %1,%4\n"
62#endif /* CONFIG_64BIT */
63 "1:\n"
64 : "+d" (reg4), "+d" (reg5)
65 : "d" (reg2), "d" (reg3), "d" (*rlen) : "cc");
66 *rlen = reg5;
67 return reg4;
68}
69
70/*
71 * __cpcmd has some restrictions over cpcmd
72 * - the response buffer must reside below 2GB (if any)
73 * - __cpcmd is unlocked and therefore not SMP-safe
74 */
75int __cpcmd(const char *cmd, char *response, int rlen, int *response_code)
76{
77 int cmdlen;
78 int rc;
79 int response_len;
80
81 cmdlen = strlen(cmd);
82 BUG_ON(cmdlen > 240);
83 memcpy(cpcmd_buf, cmd, cmdlen);
84 ASCEBC(cpcmd_buf, cmdlen);
85
86 if (response) {
87 memset(response, 0, rlen);
88 response_len = rlen;
89 rc = diag8_response(cmdlen, response, &rlen);
90 EBCASC(response, response_len);
91 } else {
92 rc = diag8_noresponse(cmdlen);
93 }
94 if (response_code)
95 *response_code = rc;
96 return rlen;
97}
98EXPORT_SYMBOL(__cpcmd);
99
100int cpcmd(const char *cmd, char *response, int rlen, int *response_code)
101{
102 char *lowbuf;
103 int len;
104 unsigned long flags;
105
106 if ((virt_to_phys(response) != (unsigned long) response) ||
107 (((unsigned long)response + rlen) >> 31)) {
108 lowbuf = kmalloc(rlen, GFP_KERNEL | GFP_DMA);
109 if (!lowbuf) {
110 pr_warning("The cpcmd kernel function failed to "
111 "allocate a response buffer\n");
112 return -ENOMEM;
113 }
114 spin_lock_irqsave(&cpcmd_lock, flags);
115 len = __cpcmd(cmd, lowbuf, rlen, response_code);
116 spin_unlock_irqrestore(&cpcmd_lock, flags);
117 memcpy(response, lowbuf, rlen);
118 kfree(lowbuf);
119 } else {
120 spin_lock_irqsave(&cpcmd_lock, flags);
121 len = __cpcmd(cmd, response, rlen, response_code);
122 spin_unlock_irqrestore(&cpcmd_lock, flags);
123 }
124 return len;
125}
126EXPORT_SYMBOL(cpcmd);