1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Hypervisor filesystem for Linux on s390. |
4 | * Set Partition-Resource Parameter interface. |
5 | * |
6 | * Copyright IBM Corp. 2013 |
7 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
8 | */ |
9 | |
10 | #include <linux/compat.h> |
11 | #include <linux/errno.h> |
12 | #include <linux/gfp.h> |
13 | #include <linux/string.h> |
14 | #include <linux/types.h> |
15 | #include <linux/uaccess.h> |
16 | #include <asm/diag.h> |
17 | #include <asm/sclp.h> |
18 | #include "hypfs.h" |
19 | |
20 | #define DIAG304_SET_WEIGHTS 0 |
21 | #define DIAG304_QUERY_PRP 1 |
22 | #define DIAG304_SET_CAPPING 2 |
23 | |
24 | #define DIAG304_CMD_MAX 2 |
25 | |
26 | static inline unsigned long __hypfs_sprp_diag304(void *data, unsigned long cmd) |
27 | { |
28 | union register_pair r1 = { .even = virt_to_phys(data), }; |
29 | |
30 | asm volatile("diag %[r1],%[r3],0x304\n" |
31 | : [r1] "+&d" (r1.pair) |
32 | : [r3] "d" (cmd) |
33 | : "memory" ); |
34 | return r1.odd; |
35 | } |
36 | |
37 | static unsigned long hypfs_sprp_diag304(void *data, unsigned long cmd) |
38 | { |
39 | diag_stat_inc(DIAG_STAT_X304); |
40 | return __hypfs_sprp_diag304(data, cmd); |
41 | } |
42 | |
43 | static void hypfs_sprp_free(const void *data) |
44 | { |
45 | free_page((unsigned long) data); |
46 | } |
47 | |
48 | static int hypfs_sprp_create(void **data_ptr, void **free_ptr, size_t *size) |
49 | { |
50 | unsigned long rc; |
51 | void *data; |
52 | |
53 | data = (void *) get_zeroed_page(GFP_KERNEL); |
54 | if (!data) |
55 | return -ENOMEM; |
56 | rc = hypfs_sprp_diag304(data, DIAG304_QUERY_PRP); |
57 | if (rc != 1) { |
58 | *data_ptr = *free_ptr = NULL; |
59 | *size = 0; |
60 | free_page((unsigned long) data); |
61 | return -EIO; |
62 | } |
63 | *data_ptr = *free_ptr = data; |
64 | *size = PAGE_SIZE; |
65 | return 0; |
66 | } |
67 | |
68 | static int __hypfs_sprp_ioctl(void __user *user_area) |
69 | { |
70 | struct hypfs_diag304 *diag304; |
71 | unsigned long cmd; |
72 | void __user *udata; |
73 | void *data; |
74 | int rc; |
75 | |
76 | rc = -ENOMEM; |
77 | data = (void *)get_zeroed_page(GFP_KERNEL); |
78 | diag304 = kzalloc(sizeof(*diag304), GFP_KERNEL); |
79 | if (!data || !diag304) |
80 | goto out; |
81 | |
82 | rc = -EFAULT; |
83 | if (copy_from_user(diag304, user_area, sizeof(*diag304))) |
84 | goto out; |
85 | rc = -EINVAL; |
86 | if ((diag304->args[0] >> 8) != 0 || diag304->args[1] > DIAG304_CMD_MAX) |
87 | goto out; |
88 | |
89 | rc = -EFAULT; |
90 | udata = (void __user *)(unsigned long) diag304->data; |
91 | if (diag304->args[1] == DIAG304_SET_WEIGHTS || |
92 | diag304->args[1] == DIAG304_SET_CAPPING) |
93 | if (copy_from_user(to: data, from: udata, PAGE_SIZE)) |
94 | goto out; |
95 | |
96 | cmd = *(unsigned long *) &diag304->args[0]; |
97 | diag304->rc = hypfs_sprp_diag304(data, cmd); |
98 | |
99 | if (diag304->args[1] == DIAG304_QUERY_PRP) |
100 | if (copy_to_user(to: udata, from: data, PAGE_SIZE)) { |
101 | rc = -EFAULT; |
102 | goto out; |
103 | } |
104 | |
105 | rc = copy_to_user(user_area, diag304, sizeof(*diag304)) ? -EFAULT : 0; |
106 | out: |
107 | kfree(objp: diag304); |
108 | free_page((unsigned long) data); |
109 | return rc; |
110 | } |
111 | |
112 | static long hypfs_sprp_ioctl(struct file *file, unsigned int cmd, |
113 | unsigned long arg) |
114 | { |
115 | void __user *argp; |
116 | |
117 | if (!capable(CAP_SYS_ADMIN)) |
118 | return -EACCES; |
119 | if (is_compat_task()) |
120 | argp = compat_ptr(uptr: arg); |
121 | else |
122 | argp = (void __user *) arg; |
123 | switch (cmd) { |
124 | case HYPFS_DIAG304: |
125 | return __hypfs_sprp_ioctl(user_area: argp); |
126 | default: /* unknown ioctl number */ |
127 | return -ENOTTY; |
128 | } |
129 | return 0; |
130 | } |
131 | |
132 | static struct hypfs_dbfs_file hypfs_sprp_file = { |
133 | .name = "diag_304" , |
134 | .data_create = hypfs_sprp_create, |
135 | .data_free = hypfs_sprp_free, |
136 | .unlocked_ioctl = hypfs_sprp_ioctl, |
137 | }; |
138 | |
139 | void hypfs_sprp_init(void) |
140 | { |
141 | if (!sclp.has_sprp) |
142 | return; |
143 | hypfs_dbfs_create_file(df: &hypfs_sprp_file); |
144 | } |
145 | |
146 | void hypfs_sprp_exit(void) |
147 | { |
148 | if (!sclp.has_sprp) |
149 | return; |
150 | hypfs_dbfs_remove_file(df: &hypfs_sprp_file); |
151 | } |
152 | |