Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
1da177e4 | 3 | * S390 version |
a53c8fab | 4 | * Copyright IBM Corp. 1999, 2007 |
1da177e4 LT |
5 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), |
6 | * Christian Borntraeger (cborntra@de.ibm.com), | |
7 | */ | |
8 | ||
2f526e5a CB |
9 | #define KMSG_COMPONENT "cpcmd" |
10 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt | |
11 | ||
1da177e4 | 12 | #include <linux/kernel.h> |
3994a52b | 13 | #include <linux/export.h> |
1da177e4 LT |
14 | #include <linux/slab.h> |
15 | #include <linux/spinlock.h> | |
16 | #include <linux/stddef.h> | |
17 | #include <linux/string.h> | |
cd4386a9 | 18 | #include <linux/mm.h> |
1ec2772e | 19 | #include <asm/diag.h> |
1da177e4 LT |
20 | #include <asm/ebcdic.h> |
21 | #include <asm/cpcmd.h> | |
bda3563f | 22 | #include <asm/io.h> |
1da177e4 LT |
23 | |
24 | static DEFINE_SPINLOCK(cpcmd_lock); | |
6b979de3 | 25 | static char cpcmd_buf[241]; |
1da177e4 | 26 | |
a004fb0c HC |
27 | static 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( | |
a004fb0c | 33 | " diag %1,%0,0x8\n" |
a004fb0c HC |
34 | : "+d" (reg3) : "d" (reg2) : "cc"); |
35 | return reg3; | |
36 | } | |
37 | ||
38 | static 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( | |
a004fb0c | 46 | " diag %2,%0,0x8\n" |
a004fb0c HC |
47 | " brc 8,1f\n" |
48 | " agr %1,%4\n" | |
a004fb0c HC |
49 | "1:\n" |
50 | : "+d" (reg4), "+d" (reg5) | |
51 | : "d" (reg2), "d" (reg3), "d" (*rlen) : "cc"); | |
52 | *rlen = reg5; | |
53 | return reg4; | |
54 | } | |
55 | ||
1da177e4 | 56 | /* |
740b5706 | 57 | * __cpcmd has some restrictions over cpcmd |
740b5706 | 58 | * - __cpcmd is unlocked and therefore not SMP-safe |
1da177e4 | 59 | */ |
6b979de3 | 60 | int __cpcmd(const char *cmd, char *response, int rlen, int *response_code) |
1da177e4 | 61 | { |
a004fb0c HC |
62 | int cmdlen; |
63 | int rc; | |
64 | int response_len; | |
1da177e4 | 65 | |
1da177e4 LT |
66 | cmdlen = strlen(cmd); |
67 | BUG_ON(cmdlen > 240); | |
6b979de3 | 68 | memcpy(cpcmd_buf, cmd, cmdlen); |
1da177e4 LT |
69 | ASCEBC(cpcmd_buf, cmdlen); |
70 | ||
1ec2772e | 71 | diag_stat_inc(DIAG_STAT_X008); |
a004fb0c | 72 | if (response) { |
1da177e4 | 73 | memset(response, 0, rlen); |
a004fb0c HC |
74 | response_len = rlen; |
75 | rc = diag8_response(cmdlen, response, &rlen); | |
76 | EBCASC(response, response_len); | |
1da177e4 | 77 | } else { |
a004fb0c | 78 | rc = diag8_noresponse(cmdlen); |
1da177e4 | 79 | } |
a004fb0c HC |
80 | if (response_code) |
81 | *response_code = rc; | |
82 | return rlen; | |
1da177e4 | 83 | } |
1da177e4 LT |
84 | EXPORT_SYMBOL(__cpcmd); |
85 | ||
6b979de3 | 86 | int cpcmd(const char *cmd, char *response, int rlen, int *response_code) |
1da177e4 | 87 | { |
cd4386a9 | 88 | unsigned long flags; |
1da177e4 | 89 | char *lowbuf; |
6b979de3 CB |
90 | int len; |
91 | ||
cd4386a9 HC |
92 | if (is_vmalloc_or_module_addr(response)) { |
93 | lowbuf = kmalloc(rlen, GFP_KERNEL); | |
1da177e4 | 94 | if (!lowbuf) { |
baebc70a | 95 | pr_warn("The cpcmd kernel function failed to allocate a response buffer\n"); |
6b979de3 | 96 | return -ENOMEM; |
1da177e4 | 97 | } |
740b5706 | 98 | spin_lock_irqsave(&cpcmd_lock, flags); |
6b979de3 | 99 | len = __cpcmd(cmd, lowbuf, rlen, response_code); |
740b5706 | 100 | spin_unlock_irqrestore(&cpcmd_lock, flags); |
1da177e4 LT |
101 | memcpy(response, lowbuf, rlen); |
102 | kfree(lowbuf); | |
bda3563f CB |
103 | } else { |
104 | spin_lock_irqsave(&cpcmd_lock, flags); | |
105 | len = __cpcmd(cmd, response, rlen, response_code); | |
106 | spin_unlock_irqrestore(&cpcmd_lock, flags); | |
1da177e4 | 107 | } |
6b979de3 | 108 | return len; |
1da177e4 | 109 | } |
1da177e4 | 110 | EXPORT_SYMBOL(cpcmd); |