Martin Schwidefsky | 07be038 | 2014-01-24 09:18:52 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Hypervisor filesystem for Linux on s390. |
| 3 | * Set Partition-Resource Parameter interface. |
| 4 | * |
| 5 | * Copyright IBM Corp. 2013 |
| 6 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
| 7 | */ |
| 8 | |
| 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" |
| 18 | |
| 19 | #define DIAG304_SET_WEIGHTS 0 |
| 20 | #define DIAG304_QUERY_PRP 1 |
| 21 | #define DIAG304_SET_CAPPING 2 |
| 22 | |
| 23 | #define DIAG304_CMD_MAX 2 |
| 24 | |
| 25 | static unsigned long hypfs_sprp_diag304(void *data, unsigned long cmd) |
| 26 | { |
| 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; |
| 30 | |
| 31 | asm volatile("diag %1,%2,0x304\n" |
| 32 | : "=d" (_rc) : "d" (_data), "d" (_cmd) : "memory"); |
| 33 | |
| 34 | return _rc; |
| 35 | } |
| 36 | |
| 37 | static void hypfs_sprp_free(const void *data) |
| 38 | { |
| 39 | free_page((unsigned long) data); |
| 40 | } |
| 41 | |
| 42 | static int hypfs_sprp_create(void **data_ptr, void **free_ptr, size_t *size) |
| 43 | { |
| 44 | unsigned long rc; |
| 45 | void *data; |
| 46 | |
| 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; |
| 56 | } |
| 57 | *data_ptr = *free_ptr = data; |
| 58 | *size = PAGE_SIZE; |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | static int __hypfs_sprp_ioctl(void __user *user_area) |
| 63 | { |
| 64 | struct hypfs_diag304 diag304; |
| 65 | unsigned long cmd; |
| 66 | void __user *udata; |
| 67 | void *data; |
| 68 | int rc; |
| 69 | |
| 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; |
| 74 | |
| 75 | data = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
| 76 | if (!data) |
| 77 | return -ENOMEM; |
| 78 | |
| 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; |
| 85 | } |
| 86 | |
| 87 | cmd = *(unsigned long *) &diag304.args[0]; |
| 88 | diag304.rc = hypfs_sprp_diag304(data, cmd); |
| 89 | |
| 90 | if (diag304.args[1] == DIAG304_QUERY_PRP) |
| 91 | if (copy_to_user(udata, data, PAGE_SIZE)) { |
| 92 | rc = -EFAULT; |
| 93 | goto out; |
| 94 | } |
| 95 | |
| 96 | rc = copy_to_user(user_area, &diag304, sizeof(diag304)) ? -EFAULT : 0; |
| 97 | out: |
| 98 | free_page((unsigned long) data); |
| 99 | return rc; |
| 100 | } |
| 101 | |
| 102 | static long hypfs_sprp_ioctl(struct file *file, unsigned int cmd, |
| 103 | unsigned long arg) |
| 104 | { |
| 105 | void __user *argp; |
| 106 | |
| 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; |
| 118 | } |
| 119 | return 0; |
| 120 | } |
| 121 | |
| 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, |
| 127 | }; |
| 128 | |
| 129 | int hypfs_sprp_init(void) |
| 130 | { |
David Hildenbrand | 37c5f6c | 2015-05-06 13:18:59 +0200 | [diff] [blame^] | 131 | if (!sclp.has_sprp) |
Martin Schwidefsky | 07be038 | 2014-01-24 09:18:52 +0100 | [diff] [blame] | 132 | return 0; |
| 133 | return hypfs_dbfs_create_file(&hypfs_sprp_file); |
| 134 | } |
| 135 | |
| 136 | void hypfs_sprp_exit(void) |
| 137 | { |
David Hildenbrand | 37c5f6c | 2015-05-06 13:18:59 +0200 | [diff] [blame^] | 138 | if (!sclp.has_sprp) |
Martin Schwidefsky | 07be038 | 2014-01-24 09:18:52 +0100 | [diff] [blame] | 139 | return; |
| 140 | hypfs_dbfs_remove_file(&hypfs_sprp_file); |
| 141 | } |