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 { 131 if (!sclp.has_sprp) 132 return 0; 133 return hypfs_dbfs_create_file(&hypfs_sprp_file); 134 } 135 136 void hypfs_sprp_exit(void) 137 { 138 if (!sclp.has_sprp) 139 return; 140 hypfs_dbfs_remove_file(&hypfs_sprp_file); 141 } 142