UBIFS: add new flash file system

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>

1 files changed, 204 insertions, 0 deletions

diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
new file mode 100644
index 000000000000..5e82cffe9695
--- /dev/null
+++ b/fs/ubifs/ioctl.c
@@ -0,0 +1,204 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * 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
+ *
+ * Authors: Zoltan Sogor
+ *          Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ */
+
+/* This file implements EXT2-compatible extended attribute ioctl() calls */
+
+#include <linux/compat.h>
+#include <linux/smp_lock.h>
+#include <linux/mount.h>
+#include "ubifs.h"
+
+/**
+ * ubifs_set_inode_flags - set VFS inode flags.
+ * @inode: VFS inode to set flags for
+ *
+ * This function propagates flags from UBIFS inode object to VFS inode object.
+ */
+void ubifs_set_inode_flags(struct inode *inode)
+{
+        unsigned int flags = ubifs_inode(inode)->flags;
+
+        inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_DIRSYNC);
+        if (flags & UBIFS_SYNC_FL)
+                inode->i_flags |= S_SYNC;
+        if (flags & UBIFS_APPEND_FL)
+                inode->i_flags |= S_APPEND;
+        if (flags & UBIFS_IMMUTABLE_FL)
+                inode->i_flags |= S_IMMUTABLE;
+        if (flags & UBIFS_DIRSYNC_FL)
+                inode->i_flags |= S_DIRSYNC;
+}
+
+/*
+ * ioctl2ubifs - convert ioctl inode flags to UBIFS inode flags.
+ * @ioctl_flags: flags to convert
+ *
+ * This function convert ioctl flags (@FS_COMPR_FL, etc) to UBIFS inode flags
+ * (@UBIFS_COMPR_FL, etc).
+ */
+static int ioctl2ubifs(int ioctl_flags)
+{
+        int ubifs_flags = 0;
+
+        if (ioctl_flags & FS_COMPR_FL)
+                ubifs_flags |= UBIFS_COMPR_FL;
+        if (ioctl_flags & FS_SYNC_FL)
+                ubifs_flags |= UBIFS_SYNC_FL;
+        if (ioctl_flags & FS_APPEND_FL)
+                ubifs_flags |= UBIFS_APPEND_FL;
+        if (ioctl_flags & FS_IMMUTABLE_FL)
+                ubifs_flags |= UBIFS_IMMUTABLE_FL;
+        if (ioctl_flags & FS_DIRSYNC_FL)
+                ubifs_flags |= UBIFS_DIRSYNC_FL;
+
+        return ubifs_flags;
+}
+
+/*
+ * ubifs2ioctl - convert UBIFS inode flags to ioctl inode flags.
+ * @ubifs_flags: flags to convert
+ *
+ * This function convert UBIFS (@UBIFS_COMPR_FL, etc) to ioctl flags
+ * (@FS_COMPR_FL, etc).
+ */
+static int ubifs2ioctl(int ubifs_flags)
+{
+        int ioctl_flags = 0;
+
+        if (ubifs_flags & UBIFS_COMPR_FL)
+                ioctl_flags |= FS_COMPR_FL;
+        if (ubifs_flags & UBIFS_SYNC_FL)
+                ioctl_flags |= FS_SYNC_FL;
+        if (ubifs_flags & UBIFS_APPEND_FL)
+                ioctl_flags |= FS_APPEND_FL;
+        if (ubifs_flags & UBIFS_IMMUTABLE_FL)
+                ioctl_flags |= FS_IMMUTABLE_FL;
+        if (ubifs_flags & UBIFS_DIRSYNC_FL)
+                ioctl_flags |= FS_DIRSYNC_FL;
+
+        return ioctl_flags;
+}
+
+static int setflags(struct inode *inode, int flags)
+{
+        int oldflags, err, release;
+        struct ubifs_inode *ui = ubifs_inode(inode);
+        struct ubifs_info *c = inode->i_sb->s_fs_info;
+        struct ubifs_budget_req req = { .dirtied_ino = 1,
+                                        .dirtied_ino_d = ui->data_len };
+
+        err = ubifs_budget_space(c, &req);
+        if (err)
+                return err;
+
+        /*
+         * The IMMUTABLE and APPEND_ONLY flags can only be changed by
+         * the relevant capability.
+         */
+        mutex_lock(&ui->ui_mutex);
+        oldflags = ubifs2ioctl(ui->flags);
+        if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
+                if (!capable(CAP_LINUX_IMMUTABLE)) {
+                        err = -EPERM;
+                        goto out_unlock;
+                }
+        }
+
+        ui->flags = ioctl2ubifs(flags);
+        ubifs_set_inode_flags(inode);
+        inode->i_ctime = ubifs_current_time(inode);
+        release = ui->dirty;
+        mark_inode_dirty_sync(inode);
+        mutex_unlock(&ui->ui_mutex);
+
+        if (release)
+                ubifs_release_budget(c, &req);
+        if (IS_SYNC(inode))
+                err = write_inode_now(inode, 1);
+        return err;
+
+out_unlock:
+        ubifs_err("can't modify inode %lu attributes", inode->i_ino);
+        mutex_unlock(&ui->ui_mutex);
+        ubifs_release_budget(c, &req);
+        return err;
+}
+
+long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+        int flags, err;
+        struct inode *inode = file->f_path.dentry->d_inode;
+
+        switch (cmd) {
+        case FS_IOC_GETFLAGS:
+                flags = ubifs2ioctl(ubifs_inode(inode)->flags);
+
+                return put_user(flags, (int __user *) arg);
+
+        case FS_IOC_SETFLAGS: {
+                if (IS_RDONLY(inode))
+                        return -EROFS;
+
+                if (!is_owner_or_cap(inode))
+                        return -EACCES;
+
+                if (get_user(flags, (int __user *) arg))
+                        return -EFAULT;
+
+                if (!S_ISDIR(inode->i_mode))
+                        flags &= ~FS_DIRSYNC_FL;
+
+                /*
+                 * Make sure the file-system is read-write and make sure it
+                 * will not become read-only while we are changing the flags.
+                 */
+                err = mnt_want_write(file->f_path.mnt);
+                if (err)
+                        return err;
+                err = setflags(inode, flags);
+                mnt_drop_write(file->f_path.mnt);
+                return err;
+        }
+
+        default:
+                return -ENOTTY;
+        }
+}
+
+#ifdef CONFIG_COMPAT
+long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+        switch (cmd) {
+        case FS_IOC32_GETFLAGS:
+                cmd = FS_IOC_GETFLAGS;
+                break;
+        case FS_IOC32_SETFLAGS:
+                cmd = FS_IOC_SETFLAGS;
+                break;
+        default:
+                return -ENOIOCTLCMD;
+        }
+        return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif