aufs: add files

[pandora-kernel.git] / fs / aufs / ioctl.c

diff --git a/fs/aufs/ioctl.c b/fs/aufs/ioctl.c
new file mode 100644 (file)
index 0000000..e669508
--- /dev/null
+++ b/fs/aufs/ioctl.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2005-2011 Junjiro R. Okajima
+ *
+ * This program, aufs is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+/*
+ * ioctl
+ * plink-management and readdir in userspace.
+ * assist the pathconf(3) wrapper library.
+ */
+
+#include <linux/file.h>
+#include "aufs.h"
+
+static int au_wbr_fd(struct path *path)
+{
+       int err, fd;
+       aufs_bindex_t wbi, bindex, bend;
+       struct file *h_file;
+       struct super_block *sb;
+       struct dentry *root;
+       struct au_branch *wbr;
+
+       err = get_unused_fd();
+       if (unlikely(err < 0))
+               goto out;
+       fd = err;
+
+       wbi = 0;
+       sb = path->dentry->d_sb;
+       root = sb->s_root;
+       aufs_read_lock(root, AuLock_IR);
+       wbr = au_sbr(sb, wbi);
+       if (!(path->mnt->mnt_flags & MNT_READONLY)
+           && !au_br_writable(wbr->br_perm)) {
+               bend = au_sbend(sb);
+               for (bindex = 1; bindex <= bend; bindex++) {
+                       wbr = au_sbr(sb, bindex);
+                       if (au_br_writable(wbr->br_perm)) {
+                               wbi = bindex;
+                               break;
+                       }
+               }
+               wbr = au_sbr(sb, wbi);
+       }
+       AuDbg("wbi %d\n", wbi);
+       h_file = au_h_open(root, wbi, O_RDONLY | O_DIRECTORY | O_LARGEFILE,
+                          NULL);
+       aufs_read_unlock(root, AuLock_IR);
+       err = PTR_ERR(h_file);
+       if (IS_ERR(h_file))
+               goto out_fd;
+
+       atomic_dec(&wbr->br_count); /* cf. au_h_open() */
+       fd_install(fd, h_file);
+       err = fd;
+       goto out; /* success */
+
+out_fd:
+       put_unused_fd(fd);
+out:
+       return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+long aufs_ioctl_dir(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       long err;
+
+       switch (cmd) {
+       case AUFS_CTL_RDU:
+       case AUFS_CTL_RDU_INO:
+               err = au_rdu_ioctl(file, cmd, arg);
+               break;
+
+       case AUFS_CTL_WBR_FD:
+               err = au_wbr_fd(&file->f_path);
+               break;
+
+       case AUFS_CTL_IBUSY:
+               err = au_ibusy_ioctl(file, arg);
+               break;
+
+       default:
+               /* do not call the lower */
+               AuDbg("0x%x\n", cmd);
+               err = -ENOTTY;
+       }
+
+       AuTraceErr(err);
+       return err;
+}
+
+long aufs_ioctl_nondir(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       long err;
+
+       switch (cmd) {
+       case AUFS_CTL_WBR_FD:
+               err = au_wbr_fd(&file->f_path);
+               break;
+
+       default:
+               /* do not call the lower */
+               AuDbg("0x%x\n", cmd);
+               err = -ENOTTY;
+       }
+
+       AuTraceErr(err);
+       return err;
+}
+
+#ifdef CONFIG_COMPAT
+long aufs_compat_ioctl_dir(struct file *file, unsigned int cmd,
+                          unsigned long arg)
+{
+       long err;
+
+       switch (cmd) {
+       case AUFS_CTL_RDU:
+       case AUFS_CTL_RDU_INO:
+               err = au_rdu_compat_ioctl(file, cmd, arg);
+               break;
+
+       case AUFS_CTL_IBUSY:
+               err = au_ibusy_compat_ioctl(file, arg);
+               break;
+
+       default:
+               err = aufs_ioctl_dir(file, cmd, arg);
+       }
+
+       AuTraceErr(err);
+       return err;
+}
+
+#if 0 /* unused yet */
+long aufs_compat_ioctl_nondir(struct file *file, unsigned int cmd,
+                             unsigned long arg)
+{
+       return aufs_ioctl_nondir(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+#endif