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Diffstat (limited to 'ANDROID_3.4.5/drivers/xen/xenfs/super.c')
-rw-r--r--ANDROID_3.4.5/drivers/xen/xenfs/super.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/drivers/xen/xenfs/super.c b/ANDROID_3.4.5/drivers/xen/xenfs/super.c
new file mode 100644
index 00000000..a84b53c0
--- /dev/null
+++ b/ANDROID_3.4.5/drivers/xen/xenfs/super.c
@@ -0,0 +1,139 @@
+/*
+ * 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.
+ */
+
+#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 struct inode *xenfs_make_inode(struct super_block *sb, int mode)
+{
+ struct inode *ret = new_inode(sb);
+
+ if (ret) {
+ ret->i_mode = mode;
+ ret->i_uid = ret->i_gid = 0;
+ ret->i_blocks = 0;
+ ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
+ }
+ return ret;
+}
+
+static struct dentry *xenfs_create_file(struct super_block *sb,
+ struct dentry *parent,
+ const char *name,
+ const struct file_operations *fops,
+ void *data,
+ int mode)
+{
+ struct dentry *dentry;
+ struct inode *inode;
+
+ dentry = d_alloc_name(parent, name);
+ if (!dentry)
+ return NULL;
+
+ inode = xenfs_make_inode(sb, S_IFREG | mode);
+ if (!inode) {
+ dput(dentry);
+ return NULL;
+ }
+
+ inode->i_fop = fops;
+ inode->i_private = data;
+
+ d_add(dentry, inode);
+ return dentry;
+}
+
+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[] = {
+ [1] = {},
+ { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+ {""},
+ };
+ int rc;
+
+ rc = simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files);
+ if (rc < 0)
+ return rc;
+
+ if (xen_initial_domain()) {
+ xenfs_create_file(sb, sb->s_root, "xsd_kva",
+ &xsd_kva_file_ops, NULL, S_IRUSR|S_IWUSR);
+ xenfs_create_file(sb, sb->s_root, "xsd_port",
+ &xsd_port_file_ops, NULL, S_IRUSR|S_IWUSR);
+ }
+
+ return rc;
+}
+
+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,
+};
+
+static int __init xenfs_init(void)
+{
+ if (xen_domain())
+ return register_filesystem(&xenfs_type);
+
+ printk(KERN_INFO "XENFS: 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);
+