diff options
Diffstat (limited to 'arch/s390/hypfs/hypfs_sprp.c')
-rw-r--r-- | arch/s390/hypfs/hypfs_sprp.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/s390/hypfs/hypfs_sprp.c b/arch/s390/hypfs/hypfs_sprp.c new file mode 100644 index 0000000..f043c3c --- /dev/null +++ b/arch/s390/hypfs/hypfs_sprp.c @@ -0,0 +1,141 @@ +/* + * 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/compat.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 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 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; + + if (copy_from_user(&diag304, user_area, sizeof(diag304))) + return -EFAULT; + if ((diag304.args[0] >> 8) != 0 || diag304.args[1] > DIAG304_CMD_MAX) + return -EINVAL; + + data = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); + if (!data) + return -ENOMEM; + + 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)) { + rc = -EFAULT; + 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: + 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); +} |