[PATCH 25/67] aufs sub-VFS, source

[hooanon05@yahoo.co.jp]

From: Junjiro Okajima <hooanon05@yahoo.co.jp>

	initial commit
	aufs sub-VFS, source

Signed-off-by: Junjiro Okajima <hooanon05@yahoo.co.jp>
---
 fs/aufs/vfsub.c |  653 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 653 insertions(+), 0 deletions(-)

diff --git a/fs/aufs/vfsub.c b/fs/aufs/vfsub.c
new file mode 100644
index 0000000..88d1ca0
--- /dev/null
+++ b/fs/aufs/vfsub.c
@@ -0,0 +1,653 @@
+/*
+ * Copyright (C) 2007-2008 Junjiro 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
+ */
+
+/*
+ * sub-routines for VFS
+ *
+ * $Id: vfsub.c,v 1.3 2008/05/12 00:29:11 sfjro Exp $
+ */
+// I'm going to slightly mad
+
+#include <linux/uaccess.h>
+#include "aufs.h"
+
+/* ---------------------------------------------------------------------- */
+
+void vfsub_args_init(struct vfsub_args *vargs, struct au_hin_ignore *ign,
+		     int dlgt, int force_unlink)
+{
+	do_vfsub_args_reinit(vargs, ign);
+	vargs->flags = 0;
+	if (unlikely(dlgt))
+		vfsub_fset(vargs->flags, DLGT);
+	if (force_unlink)
+		vfsub_fset(vargs->flags, FORCE_UNLINK);
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct file *vfsub_filp_open(const char *path, int oflags, int mode)
+{
+	struct file *err;
+
+	LKTRTrace("%s\n", path);
+
+	lockdep_off();
+	err = filp_open(path, oflags, mode);
+	lockdep_on();
+	if (!IS_ERR(err))
+		au_update_fuse_h_inode(err->f_vfsmnt, err->f_dentry); /*ignore*/
+	return err;
+}
+
+int vfsub_path_lookup(const char *name, unsigned int flags,
+		      struct nameidata *nd)
+{
+	int err;
+
+	LKTRTrace("%s\n", name);
+
+	/* lockdep_off(); */
+	err = path_lookup(name, flags, nd);
+	/* lockdep_on(); */
+	if (!err)
+		au_update_fuse_h_inode(nd->path.mnt, nd->path.dentry);
+	/*ignore*/
+	return err;
+}
+
+struct dentry *vfsub_lookup_one_len(const char *name, struct dentry *parent,
+				    int len)
+{
+	struct dentry *d;
+
+	LKTRTrace("%.*s/%.*s\n", AuDLNPair(parent), len, name);
+	IMustLock(parent->d_inode);
+
+	d = lookup_one_len(name, parent, len);
+	if (!IS_ERR(d))
+		au_update_fuse_h_inode(NULL, d); /*ignore*/
+	return d;
+}
+
+#ifdef CONFIG_AUFS_LHASH_PATCH
+struct dentry *vfsub__lookup_hash(struct qstr *name, struct dentry *parent,
+				  struct nameidata *nd)
+{
+	struct dentry *d;
+
+	LKTRTrace("%.*s/%.*s, nd %d\n",
+		  AuDLNPair(parent), AuLNPair(name), !!nd);
+	if (nd)
+		LKTRTrace("nd{0x%x}\n", nd->flags);
+	IMustLock(parent->d_inode);
+
+	d = __lookup_hash(name, parent, nd);
+	if (!IS_ERR(d))
+		au_update_fuse_h_inode(NULL, d); /*ignore*/
+	return d;
+}
+#endif
+
+/* ---------------------------------------------------------------------- */
+
+int do_vfsub_create(struct inode *dir, struct dentry *dentry, int mode,
+		    struct nameidata *nd)
+{
+	int err;
+	struct vfsmount *mnt;
+
+	LKTRTrace("i%lu, %.*s, 0x%x\n", dir->i_ino, AuDLNPair(dentry), mode);
+	IMustLock(dir);
+
+	err = vfs_create(dir, dentry, mode, nd);
+	if (!err) {
+		mnt = NULL;
+		if (nd)
+			mnt = nd->path.mnt;
+		/* dir inode is locked */
+		au_update_fuse_h_inode(mnt, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(mnt, dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_symlink(struct inode *dir, struct dentry *dentry,
+		     const char *symname, int mode)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s, %s, 0x%x\n",
+		  dir->i_ino, AuDLNPair(dentry), symname, mode);
+	IMustLock(dir);
+
+	err = vfs_symlink(dir, dentry, symname, mode);
+	if (!err) {
+		/* dir inode is locked */
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_mknod(struct inode *dir, struct dentry *dentry, int mode,
+		   dev_t dev)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s, 0x%x\n", dir->i_ino, AuDLNPair(dentry), mode);
+	IMustLock(dir);
+
+	err = vfs_mknod(dir, dentry, mode, dev);
+	if (!err) {
+		/* dir inode is locked */
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_link(struct dentry *src_dentry, struct inode *dir,
+		  struct dentry *dentry)
+{
+	int err;
+
+	LKTRTrace("%.*s, i%lu, %.*s\n",
+		  AuDLNPair(src_dentry), dir->i_ino, AuDLNPair(dentry));
+	IMustLock(dir);
+
+	lockdep_off();
+	err = vfs_link(src_dentry, dir, dentry);
+	lockdep_on();
+	if (!err) {
+		LKTRTrace("src_i %p, dst_i %p\n",
+			  src_dentry->d_inode, dentry->d_inode);
+		/* fuse has different memory inode for the same inumber */
+		au_update_fuse_h_inode(NULL, src_dentry); /*ignore*/
+		/* dir inode is locked */
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_rename(struct inode *src_dir, struct dentry *src_dentry,
+		    struct inode *dir, struct dentry *dentry)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s, i%lu, %.*s\n",
+		  src_dir->i_ino, AuDLNPair(src_dentry),
+		  dir->i_ino, AuDLNPair(dentry));
+	IMustLock(dir);
+	IMustLock(src_dir);
+
+	lockdep_off();
+	err = vfs_rename(src_dir, src_dentry, dir, dentry);
+	lockdep_on();
+	if (!err) {
+		/* dir inode is locked */
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, src_dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, src_dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s, 0x%x\n", dir->i_ino, AuDLNPair(dentry), mode);
+	IMustLock(dir);
+
+	err = vfs_mkdir(dir, dentry, mode);
+	if (!err) {
+		/* dir inode is locked */
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+		au_update_fuse_h_inode(NULL, dentry); /*ignore*/
+	}
+	return err;
+}
+
+int do_vfsub_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+	IMustLock(dir);
+
+	lockdep_off();
+	err = vfs_rmdir(dir, dentry);
+	lockdep_on();
+	/* dir inode is locked */
+	if (!err)
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+	return err;
+}
+
+int do_vfsub_unlink(struct inode *dir, struct dentry *dentry)
+{
+	int err;
+
+	LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+	IMustLock(dir);
+
+	/* vfs_unlink() locks inode */
+	lockdep_off();
+	err = vfs_unlink(dir, dentry);
+	lockdep_on();
+	/* dir inode is locked */
+	if (!err)
+		au_update_fuse_h_inode(NULL, dentry->d_parent); /*ignore*/
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+ssize_t do_vfsub_read_u(struct file *file, char __user *ubuf, size_t count,
+			loff_t *ppos)
+{
+	ssize_t err;
+
+	LKTRTrace("%.*s, cnt %lu, pos %Ld\n",
+		  AuDLNPair(file->f_dentry), (unsigned long)count, *ppos);
+
+	if (0 /*!au_test_nfs(file->f_vfsmnt->mnt_sb)*/)
+		err = vfs_read(file, ubuf, count, ppos);
+	else {
+		lockdep_off();
+		err = vfs_read(file, ubuf, count, ppos);
+		lockdep_on();
+	}
+	if (err >= 0)
+		au_update_fuse_h_inode(file->f_vfsmnt, file->f_dentry);
+	/*ignore*/
+	return err;
+}
+
+// kernel_read() ??
+ssize_t do_vfsub_read_k(struct file *file, void *kbuf, size_t count,
+			loff_t *ppos)
+{
+	ssize_t err;
+	mm_segment_t oldfs;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = do_vfsub_read_u(file, (char __user *)kbuf, count, ppos);
+	set_fs(oldfs);
+	return err;
+}
+
+ssize_t do_vfsub_write_u(struct file *file, const char __user *ubuf,
+			 size_t count, loff_t *ppos)
+{
+	ssize_t err;
+
+	LKTRTrace("%.*s, cnt %lu, pos %Ld\n",
+		  AuDLNPair(file->f_dentry), (unsigned long)count, *ppos);
+
+	lockdep_off();
+	err = vfs_write(file, ubuf, count, ppos);
+	lockdep_on();
+	if (err >= 0)
+		au_update_fuse_h_inode(file->f_vfsmnt, file->f_dentry);
+	/*ignore*/
+	return err;
+}
+
+ssize_t do_vfsub_write_k(struct file *file, void *kbuf, size_t count,
+			 loff_t *ppos)
+{
+	ssize_t err;
+	mm_segment_t oldfs;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = do_vfsub_write_u(file, (const char __user *)kbuf, count, ppos);
+	set_fs(oldfs);
+	return err;
+}
+
+int do_vfsub_readdir(struct file *file, filldir_t filldir, void *arg)
+{
+	int err;
+
+	LKTRTrace("%.*s\n", AuDLNPair(file->f_dentry));
+
+	lockdep_off();
+	err = vfs_readdir(file, filldir, arg);
+	lockdep_on();
+	if (err >= 0)
+		au_update_fuse_h_inode(file->f_vfsmnt, file->f_dentry);
+	/*ignore*/
+	return err;
+}
+
+#ifdef CONFIG_AUFS_SPLICE_PATCH
+long do_vfsub_splice_to(struct file *in, loff_t *ppos,
+			struct pipe_inode_info *pipe, size_t len,
+			unsigned int flags)
+{
+	long err;
+
+	LKTRTrace("%.*s, pos %Ld, len %lu, 0x%x\n",
+		  AuDLNPair(in->f_dentry), *ppos, (unsigned long)len, flags);
+
+	lockdep_off();
+	err = vfs_splice_to(in, ppos, pipe, len, flags);
+	lockdep_on();
+	if (err >= 0)
+		au_update_fuse_h_inode(in->f_vfsmnt, in->f_dentry); /*ignore*/
+	return err;
+}
+
+long do_vfsub_splice_from(struct pipe_inode_info *pipe, struct file *out,
+			  loff_t *ppos, size_t len, unsigned int flags)
+{
+	long err;
+
+	LKTRTrace("%.*s, pos %Ld, len %lu, 0x%x\n",
+		  AuDLNPair(out->f_dentry), *ppos, (unsigned long)len, flags);
+
+	lockdep_off();
+	err = vfs_splice_from(pipe, out, ppos, len, flags);
+	lockdep_on();
+	if (err >= 0)
+		au_update_fuse_h_inode(out->f_vfsmnt, out->f_dentry); /*ignore*/
+	return err;
+}
+#endif
+
+/* ---------------------------------------------------------------------- */
+
+struct au_vfsub_mkdir_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	int mode;
+	int dlgt;
+};
+
+static void au_call_vfsub_mkdir(void *args)
+{
+	struct au_vfsub_mkdir_args *a = args;
+	*a->errp = vfsub_mkdir(a->dir, a->dentry, a->mode, a->dlgt);
+}
+
+int vfsub_sio_mkdir(struct inode *dir, struct dentry *dentry, int mode,
+		    int dlgt)
+{
+	int err, do_sio, wkq_err;
+
+	LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+
+	do_sio = au_test_h_perm_sio(dir, MAY_EXEC | MAY_WRITE, dlgt);
+	if (!do_sio)
+		err = vfsub_mkdir(dir, dentry, mode, dlgt);
+	else {
+		struct au_vfsub_mkdir_args args = {
+			.errp	= &err,
+			.dir	= dir,
+			.dentry	= dentry,
+			.mode	= mode,
+			.dlgt	= dlgt
+		};
+		wkq_err = au_wkq_wait(au_call_vfsub_mkdir, &args, /*dlgt*/0);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+
+	AuTraceErr(err);
+	return err;
+}
+
+struct au_vfsub_rmdir_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	struct vfsub_args *vargs;
+};
+
+static void au_call_vfsub_rmdir(void *args)
+{
+	struct au_vfsub_rmdir_args *a = args;
+	*a->errp = vfsub_rmdir(a->dir, a->dentry, a->vargs);
+}
+
+int vfsub_sio_rmdir(struct inode *dir, struct dentry *dentry, int dlgt)
+{
+	int err, do_sio, wkq_err;
+	struct vfsub_args vargs;
+
+	LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+
+	vfsub_args_init(&vargs, /*ign*/NULL, dlgt, /*force_unlink*/0);
+	do_sio = au_test_h_perm_sio(dir, MAY_EXEC | MAY_WRITE, dlgt);
+	if (!do_sio)
+		err = vfsub_rmdir(dir, dentry, &vargs);
+	else {
+		struct au_vfsub_rmdir_args args = {
+			.errp		= &err,
+			.dir		= dir,
+			.dentry		= dentry,
+			.vargs		= &vargs
+		};
+		wkq_err = au_wkq_wait(au_call_vfsub_rmdir, &args, /*dlgt*/0);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+
+	AuTraceErr(err);
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct notify_change_args {
+	int *errp;
+	struct dentry *h_dentry;
+	struct iattr *ia;
+	struct vfsub_args *vargs;
+};
+
+static void call_notify_change(void *args)
+{
+	struct notify_change_args *a = args;
+	struct inode *h_inode;
+
+	LKTRTrace("%.*s, ia_valid 0x%x\n",
+		  AuDLNPair(a->h_dentry), a->ia->ia_valid);
+	h_inode = a->h_dentry->d_inode;
+	IMustLock(h_inode);
+
+	*a->errp = -EPERM;
+	if (!IS_IMMUTABLE(h_inode) && !IS_APPEND(h_inode)) {
+		vfsub_ignore(a->vargs);
+		lockdep_off();
+		*a->errp = notify_change(a->h_dentry, a->ia);
+		lockdep_on();
+		if (!*a->errp)
+			au_update_fuse_h_inode(NULL, a->h_dentry); /*ignore*/
+		else
+			vfsub_unignore(a->vargs);
+	}
+	AuTraceErr(*a->errp);
+}
+
+#ifdef CONFIG_AUFS_DLGT
+static void vfsub_notify_change_dlgt(struct notify_change_args *args,
+				     unsigned int flags)
+{
+	if (!vfsub_ftest(flags, DLGT))
+		call_notify_change(args);
+	else {
+		int wkq_err;
+		wkq_err = au_wkq_wait(call_notify_change, args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			*args->errp = wkq_err;
+	}
+}
+#else
+static void vfsub_notify_change_dlgt(struct notify_change_args *args,
+				     unsigned int flags)
+{
+	call_notify_change(args);
+}
+#endif
+
+int vfsub_notify_change(struct dentry *dentry, struct iattr *ia,
+			struct vfsub_args *vargs)
+{
+	int err;
+	struct notify_change_args args = {
+		.errp		= &err,
+		.h_dentry	= dentry,
+		.ia		= ia,
+		.vargs		= vargs
+	};
+
+	vfsub_notify_change_dlgt(&args, vargs->flags);
+
+	AuTraceErr(err);
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct unlink_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	struct vfsub_args *vargs;
+};
+
+static void call_unlink(void *args)
+{
+	struct unlink_args *a = args;
+	struct inode *h_inode;
+	const int stop_sillyrename = (au_test_nfs(a->dentry->d_sb)
+				      && atomic_read(&a->dentry->d_count) == 1);
+
+	LKTRTrace("%.*s, stop_silly %d, cnt %d\n",
+		  AuDLNPair(a->dentry), stop_sillyrename,
+		  atomic_read(&a->dentry->d_count));
+	//IMustLock(a->dir);
+
+	if (!stop_sillyrename)
+		dget(a->dentry);
+	h_inode = a->dentry->d_inode;
+	if (h_inode)
+		atomic_inc_return(&h_inode->i_count);
+#if 0 // partial testing
+	{
+		struct qstr *name = &a->dentry->d_name;
+		if (name->len == sizeof(AUFS_XINO_FNAME) - 1
+		    && !strncmp(name->name, AUFS_XINO_FNAME, name->len))
+			*a->errp = do_vfsub_unlink(a->dir, a->dentry);
+		else
+			err = -1;
+	}
+#else
+	*a->errp = do_vfsub_unlink(a->dir, a->dentry);
+#endif
+
+	if (!stop_sillyrename)
+		dput(a->dentry);
+	if (h_inode)
+		iput(h_inode);
+
+	AuTraceErr(*a->errp);
+}
+
+/*
+ * @dir: must be locked.
+ * @dentry: target dentry.
+ */
+int vfsub_unlink(struct inode *dir, struct dentry *dentry,
+		 struct vfsub_args *vargs)
+{
+	int err;
+	struct unlink_args args = {
+		.errp	= &err,
+		.dir	= dir,
+		.dentry	= dentry,
+		.vargs	= vargs
+	};
+
+	if (!vfsub_ftest(vargs->flags, DLGT)
+	    && !vfsub_ftest(vargs->flags, FORCE_UNLINK))
+		call_unlink(&args);
+	else {
+		int wkq_err;
+		wkq_err = au_wkq_wait(call_unlink, &args,
+				      vfsub_ftest(vargs->flags, DLGT));
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct statfs_args {
+	int *errp;
+	void *arg;
+	struct kstatfs *buf;
+};
+
+static void call_statfs(void *args)
+{
+	struct statfs_args *a = args;
+	*a->errp = vfs_statfs(a->arg, a->buf);
+}
+
+#ifdef CONFIG_AUFS_DLGT
+static void vfsub_statfs_dlgt(struct statfs_args *args, int dlgt)
+{
+	if (!dlgt)
+		call_statfs(args);
+	else {
+		int wkq_err;
+		wkq_err = au_wkq_wait(call_statfs, args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			*args->errp = wkq_err;
+	}
+}
+#else
+static void vfsub_statfs_dlgt(struct statfs_args *args, int dlgt)
+{
+	call_statfs(args);
+}
+#endif
+
+int vfsub_statfs(void *arg, struct kstatfs *buf, int dlgt)
+{
+	int err;
+	struct statfs_args args = {
+		.errp	= &err,
+		.arg	= arg,
+		.buf	= buf
+	};
+
+	vfsub_statfs_dlgt(&args, dlgt);
+
+	return err;
+}
-- 
1.4.4.4