| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Hypervisor filesystem for Linux on s390. |
| * Set Partition-Resource Parameter interface. |
| * |
| * Copyright IBM Corp. 2013 |
| * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
| */ |
| |
| #include <linux/compat.h> |
| #include <linux/errno.h> |
| #include <linux/gfp.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <linux/uaccess.h> |
| #include <asm/diag.h> |
| #include <asm/sclp.h> |
| #include "hypfs.h" |
| |
| #define DIAG304_SET_WEIGHTS 0 |
| #define DIAG304_QUERY_PRP 1 |
| #define DIAG304_SET_CAPPING 2 |
| |
| #define DIAG304_CMD_MAX 2 |
| |
| static inline unsigned long __hypfs_sprp_diag304(void *data, unsigned long cmd) |
| { |
| register unsigned long _data asm("2") = (unsigned long) data; |
| register unsigned long _rc asm("3"); |
| register unsigned long _cmd asm("4") = cmd; |
| |
| asm volatile("diag %1,%2,0x304\n" |
| : "=d" (_rc) : "d" (_data), "d" (_cmd) : "memory"); |
| |
| return _rc; |
| } |
| |
| static unsigned long hypfs_sprp_diag304(void *data, unsigned long cmd) |
| { |
| diag_stat_inc(DIAG_STAT_X304); |
| return __hypfs_sprp_diag304(data, cmd); |
| } |
| |
| static void hypfs_sprp_free(const void *data) |
| { |
| free_page((unsigned long) data); |
| } |
| |
| static int hypfs_sprp_create(void **data_ptr, void **free_ptr, size_t *size) |
| { |
| unsigned long rc; |
| void *data; |
| |
| data = (void *) get_zeroed_page(GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| rc = hypfs_sprp_diag304(data, DIAG304_QUERY_PRP); |
| if (rc != 1) { |
| *data_ptr = *free_ptr = NULL; |
| *size = 0; |
| free_page((unsigned long) data); |
| return -EIO; |
| } |
| *data_ptr = *free_ptr = data; |
| *size = PAGE_SIZE; |
| return 0; |
| } |
| |
| static int __hypfs_sprp_ioctl(void __user *user_area) |
| { |
| struct hypfs_diag304 *diag304; |
| unsigned long cmd; |
| void __user *udata; |
| void *data; |
| int rc; |
| |
| rc = -ENOMEM; |
| data = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); |
| diag304 = kzalloc(sizeof(*diag304), GFP_KERNEL); |
| if (!data || !diag304) |
| goto out; |
| |
| rc = -EFAULT; |
| if (copy_from_user(diag304, user_area, sizeof(*diag304))) |
| goto out; |
| rc = -EINVAL; |
| if ((diag304->args[0] >> 8) != 0 || diag304->args[1] > DIAG304_CMD_MAX) |
| goto out; |
| |
| rc = -EFAULT; |
| udata = (void __user *)(unsigned long) diag304->data; |
| if (diag304->args[1] == DIAG304_SET_WEIGHTS || |
| diag304->args[1] == DIAG304_SET_CAPPING) |
| if (copy_from_user(data, udata, PAGE_SIZE)) |
| goto out; |
| |
| cmd = *(unsigned long *) &diag304->args[0]; |
| diag304->rc = hypfs_sprp_diag304(data, cmd); |
| |
| if (diag304->args[1] == DIAG304_QUERY_PRP) |
| if (copy_to_user(udata, data, PAGE_SIZE)) { |
| rc = -EFAULT; |
| goto out; |
| } |
| |
| rc = copy_to_user(user_area, diag304, sizeof(*diag304)) ? -EFAULT : 0; |
| out: |
| kfree(diag304); |
| free_page((unsigned long) data); |
| return rc; |
| } |
| |
| static long hypfs_sprp_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| void __user *argp; |
| |
| if (!capable(CAP_SYS_ADMIN)) |
| return -EACCES; |
| if (is_compat_task()) |
| argp = compat_ptr(arg); |
| else |
| argp = (void __user *) arg; |
| switch (cmd) { |
| case HYPFS_DIAG304: |
| return __hypfs_sprp_ioctl(argp); |
| default: /* unknown ioctl number */ |
| return -ENOTTY; |
| } |
| return 0; |
| } |
| |
| static struct hypfs_dbfs_file hypfs_sprp_file = { |
| .name = "diag_304", |
| .data_create = hypfs_sprp_create, |
| .data_free = hypfs_sprp_free, |
| .unlocked_ioctl = hypfs_sprp_ioctl, |
| }; |
| |
| int hypfs_sprp_init(void) |
| { |
| if (!sclp.has_sprp) |
| return 0; |
| return hypfs_dbfs_create_file(&hypfs_sprp_file); |
| } |
| |
| void hypfs_sprp_exit(void) |
| { |
| if (!sclp.has_sprp) |
| return; |
| hypfs_dbfs_remove_file(&hypfs_sprp_file); |
| } |