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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 | // SPDX-License-Identifier: GPL-2.0 /* * IOCTL interface for SCLP * * Copyright IBM Corp. 2012 * * Author: Michael Holzheu <holzheu@linux.vnet.ibm.com> */ #include <linux/compat.h> #include <linux/uaccess.h> #include <linux/miscdevice.h> #include <linux/gfp.h> #include <linux/init.h> #include <linux/ioctl.h> #include <linux/fs.h> #include <asm/sclp_ctl.h> #include <asm/sclp.h> #include "sclp.h" /* * Supported command words */ static unsigned int sclp_ctl_sccb_wlist[] = { 0x00400002, 0x00410002, }; /* * Check if command word is supported */ static int sclp_ctl_cmdw_supported(unsigned int cmdw) { int i; for (i = 0; i < ARRAY_SIZE(sclp_ctl_sccb_wlist); i++) { if (cmdw == sclp_ctl_sccb_wlist[i]) return 1; } return 0; } static void __user *u64_to_uptr(u64 value) { if (is_compat_task()) return compat_ptr(value); else return (void __user *)(unsigned long)value; } /* * Start SCLP request */ static int sclp_ctl_ioctl_sccb(void __user *user_area) { struct sclp_ctl_sccb ctl_sccb; struct sccb_header *sccb; unsigned long copied; int rc; if (copy_from_user(&ctl_sccb, user_area, sizeof(ctl_sccb))) return -EFAULT; if (!sclp_ctl_cmdw_supported(ctl_sccb.cmdw)) return -EOPNOTSUPP; sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); if (!sccb) return -ENOMEM; copied = PAGE_SIZE - copy_from_user(sccb, u64_to_uptr(ctl_sccb.sccb), PAGE_SIZE); if (offsetof(struct sccb_header, length) + sizeof(sccb->length) > copied || sccb->length > copied) { rc = -EFAULT; goto out_free; } if (sccb->length < 8) { rc = -EINVAL; goto out_free; } rc = sclp_sync_request(ctl_sccb.cmdw, sccb); if (rc) goto out_free; if (copy_to_user(u64_to_uptr(ctl_sccb.sccb), sccb, sccb->length)) rc = -EFAULT; out_free: free_page((unsigned long) sccb); return rc; } /* * SCLP SCCB ioctl function */ static long sclp_ctl_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { void __user *argp; if (is_compat_task()) argp = compat_ptr(arg); else argp = (void __user *) arg; switch (cmd) { case SCLP_CTL_SCCB: return sclp_ctl_ioctl_sccb(argp); default: /* unknown ioctl number */ return -ENOTTY; } } /* * File operations */ static const struct file_operations sclp_ctl_fops = { .owner = THIS_MODULE, .open = nonseekable_open, .unlocked_ioctl = sclp_ctl_ioctl, .compat_ioctl = sclp_ctl_ioctl, .llseek = no_llseek, }; /* * Misc device definition */ static struct miscdevice sclp_ctl_device = { .minor = MISC_DYNAMIC_MINOR, .name = "sclp", .fops = &sclp_ctl_fops, }; builtin_misc_device(sclp_ctl_device); |