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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/xen/xenfs
Initial import
Diffstat (limited to 'drivers/xen/xenfs')
-rw-r--r--drivers/xen/xenfs/Makefile4
-rw-r--r--drivers/xen/xenfs/super.c99
-rw-r--r--drivers/xen/xenfs/xenfs.h7
-rw-r--r--drivers/xen/xenfs/xenstored.c68
4 files changed, 178 insertions, 0 deletions
diff --git a/drivers/xen/xenfs/Makefile b/drivers/xen/xenfs/Makefile
new file mode 100644
index 000000000..b019865fc
--- /dev/null
+++ b/drivers/xen/xenfs/Makefile
@@ -0,0 +1,4 @@
+obj-$(CONFIG_XENFS) += xenfs.o
+
+xenfs-y = super.o
+xenfs-$(CONFIG_XEN_DOM0) += xenstored.o
diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
new file mode 100644
index 000000000..06092e0fe
--- /dev/null
+++ b/drivers/xen/xenfs/super.c
@@ -0,0 +1,99 @@
+/*
+ * xenfs.c - a filesystem for passing info between the a domain and
+ * the hypervisor.
+ *
+ * 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
+ * and /proc/xen compatibility mount point.
+ * Turned xenfs into a loadable module.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/magic.h>
+
+#include <xen/xen.h>
+
+#include "xenfs.h"
+#include "../privcmd.h"
+#include "../xenbus/xenbus_comms.h"
+
+#include <asm/xen/hypervisor.h>
+
+MODULE_DESCRIPTION("Xen filesystem");
+MODULE_LICENSE("GPL");
+
+static ssize_t capabilities_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ char *tmp = "";
+
+ if (xen_initial_domain())
+ tmp = "control_d\n";
+
+ return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp));
+}
+
+static const struct file_operations capabilities_file_ops = {
+ .read = capabilities_read,
+ .llseek = default_llseek,
+};
+
+static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ static struct tree_descr xenfs_files[] = {
+ [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+ {""},
+ };
+
+ static struct tree_descr xenfs_init_files[] = {
+ [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+ { "xsd_kva", &xsd_kva_file_ops, S_IRUSR|S_IWUSR},
+ { "xsd_port", &xsd_port_file_ops, S_IRUSR|S_IWUSR},
+ {""},
+ };
+
+ return simple_fill_super(sb, XENFS_SUPER_MAGIC,
+ xen_initial_domain() ? xenfs_init_files : xenfs_files);
+}
+
+static struct dentry *xenfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ return mount_single(fs_type, flags, data, xenfs_fill_super);
+}
+
+static struct file_system_type xenfs_type = {
+ .owner = THIS_MODULE,
+ .name = "xenfs",
+ .mount = xenfs_mount,
+ .kill_sb = kill_litter_super,
+};
+MODULE_ALIAS_FS("xenfs");
+
+static int __init xenfs_init(void)
+{
+ if (xen_domain())
+ return register_filesystem(&xenfs_type);
+
+ pr_info("not registering filesystem on non-xen platform\n");
+ return 0;
+}
+
+static void __exit xenfs_exit(void)
+{
+ if (xen_domain())
+ unregister_filesystem(&xenfs_type);
+}
+
+module_init(xenfs_init);
+module_exit(xenfs_exit);
+
diff --git a/drivers/xen/xenfs/xenfs.h b/drivers/xen/xenfs/xenfs.h
new file mode 100644
index 000000000..6b80c7779
--- /dev/null
+++ b/drivers/xen/xenfs/xenfs.h
@@ -0,0 +1,7 @@
+#ifndef _XENFS_XENBUS_H
+#define _XENFS_XENBUS_H
+
+extern const struct file_operations xsd_kva_file_ops;
+extern const struct file_operations xsd_port_file_ops;
+
+#endif /* _XENFS_XENBUS_H */
diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c
new file mode 100644
index 000000000..fef20dbc6
--- /dev/null
+++ b/drivers/xen/xenfs/xenstored.c
@@ -0,0 +1,68 @@
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+
+#include <xen/page.h>
+
+#include "xenfs.h"
+#include "../xenbus/xenbus_comms.h"
+
+static ssize_t xsd_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ const char *str = (const char *)file->private_data;
+ return simple_read_from_buffer(buf, size, off, str, strlen(str));
+}
+
+static int xsd_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static int xsd_kva_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p",
+ xen_store_interface);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ size_t size = vma->vm_end - vma->vm_start;
+
+ if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0))
+ return -EINVAL;
+
+ if (remap_pfn_range(vma, vma->vm_start,
+ virt_to_pfn(xen_store_interface),
+ size, vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+const struct file_operations xsd_kva_file_ops = {
+ .open = xsd_kva_open,
+ .mmap = xsd_kva_mmap,
+ .read = xsd_read,
+ .release = xsd_release,
+};
+
+static int xsd_port_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "%d",
+ xen_store_evtchn);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+const struct file_operations xsd_port_file_ops = {
+ .open = xsd_port_open,
+ .read = xsd_read,
+ .release = xsd_release,
+};