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-rw-r--r--arch/s390/hypfs/hypfs_sprp.c141
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 000000000000..f043c3c7e73c
--- /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);
+}