Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
[linux/fpc-iii.git] / arch / s390 / hypfs / hypfs_sprp.c
blobf043c3c7e73ccdb5706ac68019921d77df8392f0
1 /*
2 * Hypervisor filesystem for Linux on s390.
3 * Set Partition-Resource Parameter interface.
5 * Copyright IBM Corp. 2013
6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
7 */
9 #include <linux/compat.h>
10 #include <linux/errno.h>
11 #include <linux/gfp.h>
12 #include <linux/string.h>
13 #include <linux/types.h>
14 #include <linux/uaccess.h>
15 #include <asm/compat.h>
16 #include <asm/sclp.h>
17 #include "hypfs.h"
19 #define DIAG304_SET_WEIGHTS 0
20 #define DIAG304_QUERY_PRP 1
21 #define DIAG304_SET_CAPPING 2
23 #define DIAG304_CMD_MAX 2
25 static unsigned long hypfs_sprp_diag304(void *data, unsigned long cmd)
27 register unsigned long _data asm("2") = (unsigned long) data;
28 register unsigned long _rc asm("3");
29 register unsigned long _cmd asm("4") = cmd;
31 asm volatile("diag %1,%2,0x304\n"
32 : "=d" (_rc) : "d" (_data), "d" (_cmd) : "memory");
34 return _rc;
37 static void hypfs_sprp_free(const void *data)
39 free_page((unsigned long) data);
42 static int hypfs_sprp_create(void **data_ptr, void **free_ptr, size_t *size)
44 unsigned long rc;
45 void *data;
47 data = (void *) get_zeroed_page(GFP_KERNEL);
48 if (!data)
49 return -ENOMEM;
50 rc = hypfs_sprp_diag304(data, DIAG304_QUERY_PRP);
51 if (rc != 1) {
52 *data_ptr = *free_ptr = NULL;
53 *size = 0;
54 free_page((unsigned long) data);
55 return -EIO;
57 *data_ptr = *free_ptr = data;
58 *size = PAGE_SIZE;
59 return 0;
62 static int __hypfs_sprp_ioctl(void __user *user_area)
64 struct hypfs_diag304 diag304;
65 unsigned long cmd;
66 void __user *udata;
67 void *data;
68 int rc;
70 if (copy_from_user(&diag304, user_area, sizeof(diag304)))
71 return -EFAULT;
72 if ((diag304.args[0] >> 8) != 0 || diag304.args[1] > DIAG304_CMD_MAX)
73 return -EINVAL;
75 data = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
76 if (!data)
77 return -ENOMEM;
79 udata = (void __user *)(unsigned long) diag304.data;
80 if (diag304.args[1] == DIAG304_SET_WEIGHTS ||
81 diag304.args[1] == DIAG304_SET_CAPPING)
82 if (copy_from_user(data, udata, PAGE_SIZE)) {
83 rc = -EFAULT;
84 goto out;
87 cmd = *(unsigned long *) &diag304.args[0];
88 diag304.rc = hypfs_sprp_diag304(data, cmd);
90 if (diag304.args[1] == DIAG304_QUERY_PRP)
91 if (copy_to_user(udata, data, PAGE_SIZE)) {
92 rc = -EFAULT;
93 goto out;
96 rc = copy_to_user(user_area, &diag304, sizeof(diag304)) ? -EFAULT : 0;
97 out:
98 free_page((unsigned long) data);
99 return rc;
102 static long hypfs_sprp_ioctl(struct file *file, unsigned int cmd,
103 unsigned long arg)
105 void __user *argp;
107 if (!capable(CAP_SYS_ADMIN))
108 return -EACCES;
109 if (is_compat_task())
110 argp = compat_ptr(arg);
111 else
112 argp = (void __user *) arg;
113 switch (cmd) {
114 case HYPFS_DIAG304:
115 return __hypfs_sprp_ioctl(argp);
116 default: /* unknown ioctl number */
117 return -ENOTTY;
119 return 0;
122 static struct hypfs_dbfs_file hypfs_sprp_file = {
123 .name = "diag_304",
124 .data_create = hypfs_sprp_create,
125 .data_free = hypfs_sprp_free,
126 .unlocked_ioctl = hypfs_sprp_ioctl,
129 int hypfs_sprp_init(void)
131 if (!sclp_has_sprp())
132 return 0;
133 return hypfs_dbfs_create_file(&hypfs_sprp_file);
136 void hypfs_sprp_exit(void)
138 if (!sclp_has_sprp())
139 return;
140 hypfs_dbfs_remove_file(&hypfs_sprp_file);