[Aufs 24/25] aufs test for fstype

J. R. Okajima
2009-03-09T03:32:42Z

judge the type of filesystem of branch

Signed-off-by: J. R. Okajima <hooanon05@yahoo.co.jp>
---
fs/aufs/fstype.h | 434 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/aufs/magic.mk | 52 +++++++
2 files changed, 486 insertions(+), 0 deletions(-)
create mode 100644 fs/aufs/fstype.h
create mode 100644 fs/aufs/magic.mk

diff --git a/fs/aufs/fstype.h b/fs/aufs/fstype.h
new file mode 100644
index 0000000..eac06aa
--- /dev/null
+++ b/fs/aufs/fstype.h
@@ -0,0 +1,434 @@
+/*
+ * Copyright (C) 2005-2009 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.
+ */
+
+/*
+ * judging filesystem type
+ */
+
+#ifndef __AUFS_FSTYPE_H__
+#define __AUFS_FSTYPE_H__
+
+#ifdef __KERNEL__
+
+#include <linux/fs.h>
+#include <linux/cramfs_fs.h>
+#include <linux/magic.h>
+#include <linux/romfs_fs.h>
+#include <linux/aufs_type.h>
+
+static inline int au_test_aufs(struct super_block *sb)
+{
+ return sb->s_magic == AUFS_SUPER_MAGIC;
+}
+
+static inline const char *au_sbtype(struct super_block *sb)
+{
+ return sb->s_type->name;
+}
+
+static inline int au_test_iso9660(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_ROMFS_FS) || defined(CONFIG_ROMFS_FS_MODULE)
+ return sb->s_magic == ROMFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_romfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_ISO9660_FS) || defined(CONFIG_ISO9660_FS_MODULE)
+ return sb->s_magic == ISOFS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_cramfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_CRAMFS) || defined(CONFIG_CRAMFS_MODULE)
+ return sb->s_magic == CRAMFS_MAGIC;
+#endif
+ return 0;
+}
+
+static inline int au_test_nfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_NFS_FS) || defined(CONFIG_NFS_FS_MODULE)
+ return sb->s_magic == NFS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_fuse(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_FUSE_FS) || defined(CONFIG_FUSE_FS_MODULE)
+ return sb->s_magic == FUSE_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_xfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_XFS_FS) || defined(CONFIG_XFS_FS_MODULE)
+ return sb->s_magic == XFS_SB_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_tmpfs(struct super_block *sb __maybe_unused)
+{
+#ifdef CONFIG_TMPFS
+ return sb->s_magic == TMPFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_ecryptfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_ECRYPT_FS) || defined(CONFIG_ECRYPT_FS_MODULE)
+ return !strcmp(au_sbtype(sb), "ecryptfs");
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_smbfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_SMB_FS) || defined(CONFIG_SMB_FS_MODULE)
+ return sb->s_magic == SMB_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_ocfs2(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_OCFS2_FS) || defined(CONFIG_OCFS2_FS_MODULE)
+ return sb->s_magic == OCFS2_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_ocfs2_dlmfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_OCFS2_FS_O2CB) || defined(CONFIG_OCFS2_FS_O2CB_MODULE)
+ return sb->s_magic == DLMFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_coda(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_CODA_FS) || defined(CONFIG_CODA_FS_MODULE)
+ return sb->s_magic == CODA_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_v9fs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_9P_FS) || defined(CONFIG_9P_FS_MODULE)
+ return sb->s_magic == V9FS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_ext4(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_EXT4DEV_FS) || defined(CONFIG_EXT4DEV_FS_MODULE)
+ return sb->s_magic == EXT4_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_sysv(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_SYSV_FS) || defined(CONFIG_SYSV_FS_MODULE)
+ return !strcmp(au_sbtype(sb), "sysv");
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_ramfs(struct super_block *sb)
+{
+ return sb->s_magic == RAMFS_MAGIC;
+}
+
+static inline int au_test_ubifs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_UBIFS_FS) || defined(CONFIG_UBIFS_FS_MODULE)
+ return sb->s_magic == UBIFS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_procfs(struct super_block *sb __maybe_unused)
+{
+#ifdef CONFIG_PROC_FS
+ return sb->s_magic == PROC_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_sysfs(struct super_block *sb __maybe_unused)
+{
+#ifdef CONFIG_SYSFS
+ return sb->s_magic == SYSFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_configfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_CONFIGFS_FS) || defined(CONFIG_CONFIGFS_FS_MODULE)
+ return sb->s_magic == CONFIGFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_minix(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_MINIX_FS) || defined(CONFIG_MINIX_FS_MODULE)
+ return sb->s_magic == MINIX3_SUPER_MAGIC
+ || sb->s_magic == MINIX2_SUPER_MAGIC
+ || sb->s_magic == MINIX2_SUPER_MAGIC2
+ || sb->s_magic == MINIX_SUPER_MAGIC
+ || sb->s_magic == MINIX_SUPER_MAGIC2;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_cifs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_CIFS_FS) || defined(CONFIGCIFS_FS_MODULE)
+ return sb->s_magic == CIFS_MAGIC_NUMBER;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_fat(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_FAT_FS) || defined(CONFIG_FAT_FS_MODULE)
+ return sb->s_magic == MSDOS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_msdos(struct super_block *sb)
+{
+ return au_test_fat(sb);
+}
+
+static inline int au_test_vfat(struct super_block *sb)
+{
+ return au_test_fat(sb);
+}
+
+static inline int au_test_securityfs(struct super_block *sb __maybe_unused)
+{
+#ifdef CONFIG_SECURITYFS
+ return sb->s_magic == SECURITYFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_squashfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_SQUASHFS) || defined(CONFIG_SQUASHFS_MODULE)
+ return sb->s_magic == SQUASHFS_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_btrfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_BTRFS_FS) || defined(CONFIG_BTRFS_FS_MODULE)
+ return sb->s_magic == BTRFS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+static inline int au_test_xenfs(struct super_block *sb __maybe_unused)
+{
+#if defined(CONFIG_XENFS) || defined(CONFIG_XENFS_MODULE)
+ return sb->s_magic == XENFS_SUPER_MAGIC;
+#else
+ return 0;
+#endif
+}
+
+/* ---------------------------------------------------------------------- */
+/*
+ * they can't be an aufs branch.
+ */
+static inline int au_test_fs_unsuppoted(struct super_block *sb)
+{
+ return au_test_procfs(sb)
+ || au_test_sysfs(sb)
+ || au_test_configfs(sb)
+ || au_test_securityfs(sb)
+ || au_test_xenfs(sb)
+ || au_test_ramfs(sb)
+ /* || !strcmp(au_sbtype(sb), "unionfs") */
+ || au_test_aufs(sb); /* will be supported in next version */
+}
+
+/*
+ * If the filesystem supports NFS-export, then it has to support NULL as
+ * a nameidata parameter for ->create(), ->lookup() and ->d_revalidate().
+ * We can apply this principle when we handle a lower filesystem.
+ */
+static inline int au_test_fs_null_nd(struct super_block *sb)
+{
+ return !!sb->s_export_op;
+}
+
+static inline int au_test_fs_remote(struct super_block *sb)
+{
+ return !au_test_tmpfs(sb)
+ && !(sb->s_type->fs_flags & FS_REQUIRES_DEV);
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * Note: these functions (below) are created after reading ->getattr() in all
+ * filesystems under linux/fs. it means we have to do so in every update...
+ */
+
+/*
+ * some filesystems require getattr to refresh the inode attributes before
+ * referencing.
+ * in most cases, we can rely on the inode attribute in NFS (or every remote fs)
+ * and leave the work for d_revalidate()
+ */
+static inline int au_test_fs_refresh_iattr(struct super_block *sb)
+{
+ return au_test_nfs(sb)
+ || au_test_fuse(sb)
+ /* || au_test_smbfs(sb) */ /* untested */
+ /* || au_test_ocfs2(sb) */ /* untested */
+ /* || au_test_btrfs(sb) */ /* untested */
+ /* || au_test_coda(sb) */ /* untested */
+ /* || au_test_v9fs(sb) */ /* untested */
+ ;
+}
+
+/*
+ * filesystems which don't maintain i_size or i_blocks.
+ */
+static inline int au_test_fs_bad_iattr_size(struct super_block *sb)
+{
+ return au_test_xfs(sb)
+ /* || au_test_ext4(sb) */ /* untested */
+ /* || au_test_ocfs2(sb) */ /* untested */
+ /* || au_test_ocfs2_dlmfs(sb) */ /* untested */
+ /* || au_test_sysv(sb) */ /* untested */
+ /* || au_test_ramfs(sb)*/ /* unsupported */
+ /* || au_test_ubifs(sb) */ /* untested */
+ /* || au_test_minix(sb) */ /* untested */
+ ;
+}
+
+/*
+ * filesystems which don't store the correct value in some of their inode
+ * attributes.
+ */
+static inline int au_test_fs_bad_iattr(struct super_block *sb)
+{
+ return au_test_fs_bad_iattr_size(sb)
+ /* || au_test_cifs(sb) */ /* untested */
+ || au_test_fat(sb)
+ || au_test_msdos(sb)
+ || au_test_vfat(sb);
+}
+
+/*
+ * filesystems which sets S_NOATIME and S_NOCMTIME.
+ */
+static inline int au_test_fs_notime(struct super_block *sb)
+{
+ return au_test_nfs(sb)
+ || au_test_fuse(sb)
+ /* || au_test_cifs(sb) */ /* untested */
+ /* || au_test_ubifs(sb) */ /* untested */
+ ;
+}
+
+/*
+ * filesystems which requires replacing i_mapping.
+ */
+static inline int au_test_fs_bad_mapping(struct super_block *sb)
+{
+ return au_test_fuse(sb);
+}
+
+/* temporary support for i#1 in cramfs */
+static inline int au_test_fs_unique_ino(struct inode *inode)
+{
+ if (au_test_cramfs(inode->i_sb))
+ return inode->i_ino != 1;
+ return 1;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * the filesystem where the xino files placed must support i/o after unlink and
+ * maintain i_size and i_blocks.
+ */
+static inline int au_test_fs_bad_xino(struct super_block *sb)
+{
+ return au_test_fs_remote(sb)
+ || au_test_fs_bad_iattr_size(sb)
+ || !au_test_fs_null_nd(sb) /* to keep xino code simple */
+ /* don't want unnecessary work for xino */
+ || au_test_aufs(sb)
+ || au_test_ecryptfs(sb);
+}
+
+static inline int au_test_fs_trunc_xino(struct super_block *sb)
+{
+ return au_test_tmpfs(sb);
+}
+
+/*
+ * test if the @sb is real-readonly.
+ */
+static inline int au_test_fs_rr(struct super_block *sb)
+{
+ return au_test_squashfs(sb)
+ || au_test_iso9660(sb)
+ || au_test_cramfs(sb)
+ || au_test_romfs(sb);
+}
+
+#endif /* __KERNEL__ */
+#endif /* __AUFS_FSTYPE_H__ */
diff --git a/fs/aufs/magic.mk b/fs/aufs/magic.mk
new file mode 100644
index 0000000..83d613c
--- /dev/null
+++ b/fs/aufs/magic.mk
@@ -0,0 +1,52 @@
+
+# defined in ${srctree}/fs/fuse/inode.c
+# tristate
+ifdef CONFIG_FUSE_FS
+ccflags-y += -DFUSE_SUPER_MAGIC=0x65735546
+endif
+
+# defined in ${srctree}/fs/ocfs2/ocfs2_fs.h
+# tristate
+ifdef CONFIG_OCFS2_FS
+ccflags-y += -DOCFS2_SUPER_MAGIC=0x7461636f
+endif
+
+# defined in ${srctree}/fs/ocfs2/dlm/userdlm.h
+# tristate
+ifdef CONFIG_OCFS2_FS_O2CB
+ccflags-y += -DDLMFS_MAGIC=0x76a9f425
+endif
+
+# defined in ${srctree}/fs/ramfs/inode.c
+# always true
+ccflags-y += -DRAMFS_MAGIC=0x858458f6
+
+# defined in ${srctree}/fs/cifs/cifsfs.c
+# tristate
+ifdef CONFIG_CIFS_FS
+ccflags-y += -DCIFS_MAGIC_NUMBER=0xFF534D42
+endif
+
+# defined in ${srctree}/fs/xfs/xfs_sb.h
+# tristate
+ifdef CONFIG_XFS_FS
+ccflags-y += -DXFS_SB_MAGIC=0x58465342
+endif
+
+# defined in ${srctree}/fs/configfs/mount.c
+# tristate
+ifdef CONFIG_CONFIGFS_FS
+ccflags-y += -DCONFIGFS_MAGIC=0x62656570
+endif
+
+# defined in ${srctree}/fs/9p/v9fs.h
+# tristate
+ifdef CONFIG_9P_FS
+ccflags-y += -DV9FS_MAGIC=0x01021997
+endif
+
+# defined in ${srctree}/fs/ubifs/ubifs.h
+# tristate
+ifdef CONFIG_UBIFS_FS
+ccflags-y += -DUBIFS_SUPER_MAGIC=0x24051905
+endif
--
1.6.1.284.g5dc13