[PATCH 53/67] aufs sub-routines for vfs in hinotify or dlgt mode

[hooanon05@yahoo.co.jp]

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

	initial commit
	aufs sub-routines for vfs in hinotify or dlgt mode

Signed-off-by: Junjiro Okajima <hooanon05@yahoo.co.jp>
---
 fs/aufs/hin_or_dlgt.c |  708 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 708 insertions(+), 0 deletions(-)

diff --git a/fs/aufs/hin_or_dlgt.c b/fs/aufs/hin_or_dlgt.c
new file mode 100644
index 0000000..ad0a2fc
--- /dev/null
+++ b/fs/aufs/hin_or_dlgt.c
@@ -0,0 +1,708 @@
+/*
+ * Copyright (C) 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 in hinotify or dlgt mode
+ *
+ * $Id: hin_or_dlgt.c,v 1.2 2008/04/21 02:00:37 sfjro Exp $
+ */
+// I'm going to slightly mad
+
+#include <linux/uaccess.h>
+#include "aufs.h"
+
+#if !defined(CONFIG_AUFS_HINOTIFY) && !defined(CONFIG_AUFS_DLGT)
+#error mis-configuraion or Makefile
+#endif
+
+/* ---------------------------------------------------------------------- */
+
+struct permission_args {
+	int *errp;
+	struct inode *inode;
+	int mask;
+	struct nameidata *nd;
+};
+
+static void call_permission(void *args)
+{
+	struct permission_args *a = args;
+	*a->errp = do_vfsub_permission(a->inode, a->mask, a->nd);
+}
+
+int vfsub_permission(struct inode *inode, int mask, struct nameidata *nd,
+		     int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_permission(inode, mask, nd);
+	else {
+		int err, wkq_err;
+		struct permission_args args = {
+			.errp	= &err,
+			.inode	= inode,
+			.mask	= mask,
+			.nd	= nd
+		};
+		wkq_err = au_wkq_wait(call_permission, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct create_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	int mode;
+	struct nameidata *nd;
+};
+
+static void call_create(void *args)
+{
+	struct create_args *a = args;
+	*a->errp = do_vfsub_create(a->dir, a->dentry, a->mode, a->nd);
+}
+
+int vfsub_create(struct inode *dir, struct dentry *dentry, int mode,
+		 struct nameidata *nd, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_create(dir, dentry, mode, nd);
+	else {
+		int err, wkq_err;
+		struct create_args args = {
+			.errp	= &err,
+			.dir	= dir,
+			.dentry	= dentry,
+			.mode	= mode,
+			.nd	= nd
+		};
+		wkq_err = au_wkq_wait(call_create, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct symlink_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	const char *symname;
+	int mode;
+};
+
+static void call_symlink(void *args)
+{
+	struct symlink_args *a = args;
+	*a->errp = do_vfsub_symlink(a->dir, a->dentry, a->symname, a->mode);
+}
+
+int vfsub_symlink(struct inode *dir, struct dentry *dentry, const char *symname,
+		  int mode, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_symlink(dir, dentry, symname, mode);
+	else {
+		int err, wkq_err;
+		struct symlink_args args = {
+			.errp		= &err,
+			.dir		= dir,
+			.dentry		= dentry,
+			.symname	= symname,
+			.mode		= mode
+		};
+		wkq_err = au_wkq_wait(call_symlink, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct mknod_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	int mode;
+	dev_t dev;
+};
+
+static void call_mknod(void *args)
+{
+	struct mknod_args *a = args;
+	*a->errp = do_vfsub_mknod(a->dir, a->dentry, a->mode, a->dev);
+}
+
+int vfsub_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev,
+		int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_mknod(dir, dentry, mode, dev);
+	else {
+		int err, wkq_err;
+		struct mknod_args args = {
+			.errp	= &err,
+			.dir	= dir,
+			.dentry	= dentry,
+			.mode	= mode,
+			.dev	= dev
+		};
+		wkq_err = au_wkq_wait(call_mknod, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct mkdir_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	int mode;
+};
+
+static void call_mkdir(void *args)
+{
+	struct mkdir_args *a = args;
+	*a->errp = do_vfsub_mkdir(a->dir, a->dentry, a->mode);
+}
+
+int vfsub_mkdir(struct inode *dir, struct dentry *dentry, int mode, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_mkdir(dir, dentry, mode);
+	else {
+		int err, wkq_err;
+		struct mkdir_args args = {
+			.errp	= &err,
+			.dir	= dir,
+			.dentry	= dentry,
+			.mode	= mode
+		};
+		wkq_err = au_wkq_wait(call_mkdir, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct link_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *src_dentry, *dentry;
+};
+
+static void call_link(void *args)
+{
+	struct link_args *a = args;
+	*a->errp = do_vfsub_link(a->src_dentry, a->dir, a->dentry);
+}
+
+int vfsub_link(struct dentry *src_dentry, struct inode *dir,
+	       struct dentry *dentry, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_link(src_dentry, dir, dentry);
+	else {
+		int err, wkq_err;
+		struct link_args args = {
+			.errp		= &err,
+			.src_dentry	= src_dentry,
+			.dir		= dir,
+			.dentry		= dentry
+		};
+		wkq_err = au_wkq_wait(call_link, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct rename_args {
+	int *errp;
+	struct inode *src_dir, *dir;
+	struct dentry *src_dentry, *dentry;
+	struct vfsub_args *vargs;
+};
+
+static void call_rename(void *args)
+{
+	struct rename_args *a = args;
+	vfsub_ignore(a->vargs);
+	*a->errp = do_vfsub_rename(a->src_dir, a->src_dentry, a->dir,
+				   a->dentry);
+	if (unlikely(*a->errp))
+		vfsub_unignore(a->vargs);
+}
+
+int vfsub_rename(struct inode *src_dir, struct dentry *src_dentry,
+		 struct inode *dir, struct dentry *dentry,
+		 struct vfsub_args *vargs)
+{
+	int err;
+
+	if (!vfsub_ftest(vargs->flags, DLGT)) {
+		vfsub_ignore(vargs);
+		err = do_vfsub_rename(src_dir, src_dentry, dir, dentry);
+		if (unlikely(err))
+			vfsub_unignore(vargs);
+	} else {
+		int wkq_err;
+		struct rename_args args = {
+			.errp		= &err,
+			.src_dir	= src_dir,
+			.src_dentry	= src_dentry,
+			.dir		= dir,
+			.dentry		= dentry,
+			.vargs		= vargs
+		};
+		wkq_err = au_wkq_wait(call_rename, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+	return err;
+}
+
+struct rmdir_args {
+	int *errp;
+	struct inode *dir;
+	struct dentry *dentry;
+	struct vfsub_args *vargs;
+};
+
+static void call_rmdir(void *args)
+{
+	struct rmdir_args *a = args;
+	vfsub_ignore(a->vargs);
+	*a->errp = do_vfsub_rmdir(a->dir, a->dentry);
+	if (unlikely(*a->errp))
+		vfsub_unignore(a->vargs);
+}
+
+int vfsub_rmdir(struct inode *dir, struct dentry *dentry,
+		struct vfsub_args *vargs)
+{
+	int err;
+
+	if (!vfsub_ftest(vargs->flags, DLGT)) {
+		vfsub_ignore(vargs);
+		err = do_vfsub_rmdir(dir, dentry);
+		if (unlikely(err))
+			vfsub_unignore(vargs);
+	} else {
+		int wkq_err;
+		struct rmdir_args args = {
+			.errp	= &err,
+			.dir	= dir,
+			.dentry	= dentry,
+			.vargs	= vargs
+		};
+		wkq_err = au_wkq_wait(call_rmdir, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct read_args {
+	ssize_t *errp;
+	struct file *file;
+	union {
+		void *kbuf;
+		char __user *ubuf;
+	};
+	size_t count;
+	loff_t *ppos;
+};
+
+static void call_read_k(void *args)
+{
+	struct read_args *a = args;
+	LKTRTrace("%.*s, cnt %lu, pos %Ld\n",
+		  AuDLNPair(a->file->f_dentry), (unsigned long)a->count,
+		  *a->ppos);
+	*a->errp = do_vfsub_read_k(a->file, a->kbuf, a->count, a->ppos);
+}
+
+ssize_t vfsub_read_u(struct file *file, char __user *ubuf, size_t count,
+		     loff_t *ppos, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_read_u(file, ubuf, count, ppos);
+	else {
+		int wkq_err;
+		ssize_t err, read;
+		struct read_args args = {
+			.errp	= &err,
+			.file	= file,
+			.count	= count,
+			.ppos	= ppos
+		};
+
+		if (unlikely(!count))
+			return 0;
+
+		/*
+		 * workaround an application bug.
+		 * generally, read(2) or write(2) may return the value shorter
+		 * than requested. But many applications don't support it,
+		 * for example bash.
+		 */
+		err = -ENOMEM;
+		if (args.count > PAGE_SIZE)
+			args.count = PAGE_SIZE;
+		args.kbuf = kmalloc(args.count, GFP_TEMPORARY);
+		if (unlikely(!args.kbuf))
+			goto out;
+
+		read = 0;
+		do {
+			wkq_err = au_wkq_wait(call_read_k, &args, /*dlgt*/1);
+			if (unlikely(wkq_err))
+				err = wkq_err;
+			if (unlikely(err > 0
+				     && copy_to_user(ubuf, args.kbuf, err))) {
+				err = -EFAULT;
+				goto out_free;
+			} else if (!err)
+				break;
+			else if (unlikely(err < 0))
+				goto out_free;
+			count -= err;
+			/* do not read too much because of file i/o pointer */
+			if (count < args.count)
+				args.count = count;
+			ubuf += err;
+			read += err;
+		} while (count);
+		smp_mb(); /* flush ubuf */
+		err = read;
+
+	out_free:
+		kfree(args.kbuf);
+	out:
+		return err;
+	}
+}
+
+ssize_t vfsub_read_k(struct file *file, void *kbuf, size_t count, loff_t *ppos,
+		     int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_read_k(file, kbuf, count, ppos);
+	else {
+		ssize_t err;
+		int wkq_err;
+		struct read_args args = {
+			.errp	= &err,
+			.file	= file,
+			.count	= count,
+			.ppos	= ppos
+		};
+		args.kbuf = kbuf;
+		wkq_err = au_wkq_wait(call_read_k, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct write_args {
+	ssize_t *errp;
+	struct file *file;
+	union {
+		void *kbuf;
+		const char __user *ubuf;
+	};
+	void *buf;
+	size_t count;
+	loff_t *ppos;
+	struct vfsub_args *vargs;
+};
+
+static void call_write_k(void *args)
+{
+	struct write_args *a = args;
+	LKTRTrace("%.*s, cnt %lu, pos %Ld\n",
+		  AuDLNPair(a->file->f_dentry), (unsigned long)a->count,
+		  *a->ppos);
+	vfsub_ignore(a->vargs);
+	*a->errp = do_vfsub_write_k(a->file, a->kbuf, a->count, a->ppos);
+	if (unlikely(*a->errp < 0))
+		vfsub_unignore(a->vargs);
+}
+
+ssize_t vfsub_write_u(struct file *file, const char __user *ubuf, size_t count,
+		      loff_t *ppos, struct vfsub_args *vargs)
+{
+	ssize_t err;
+
+	if (!vfsub_ftest(vargs->flags, DLGT)) {
+		vfsub_ignore(vargs);
+		err = do_vfsub_write_u(file, ubuf, count, ppos);
+		if (unlikely(err < 0))
+			vfsub_unignore(vargs);
+	} else {
+		ssize_t written;
+		int wkq_err;
+		struct write_args args = {
+			.errp	= &err,
+			.file	= file,
+			.count	= count,
+			.ppos	= ppos,
+			.vargs	= vargs
+		};
+
+		if (unlikely(!count))
+			return 0;
+
+		/*
+		 * workaround an application bug.
+		 * generally, read(2) or write(2) may return the value shorter
+		 * than requested. But many applications don't support it,
+		 * for example bash.
+		 */
+		err = -ENOMEM;
+		if (args.count > PAGE_SIZE)
+			args.count = PAGE_SIZE;
+		args.kbuf = kmalloc(args.count, GFP_TEMPORARY);
+		if (unlikely(!args.kbuf))
+			goto out;
+
+		written = 0;
+		do {
+			if (unlikely(copy_from_user(args.kbuf, ubuf,
+						    args.count))) {
+				err = -EFAULT;
+				goto out_free;
+			}
+
+			wkq_err = au_wkq_wait(call_write_k, &args, /*dlgt*/1);
+			if (unlikely(wkq_err))
+				err = wkq_err;
+			if (err > 0) {
+				count -= err;
+				if (count < args.count)
+					args.count = count;
+				ubuf += err;
+				written += err;
+			} else if (!err)
+				break;
+			else if (unlikely(err < 0))
+				goto out_free;
+		} while (count);
+		err = written;
+
+	out_free:
+		kfree(args.kbuf);
+	}
+ out:
+	return err;
+}
+
+ssize_t vfsub_write_k(struct file *file, void *kbuf, size_t count, loff_t *ppos,
+		      struct vfsub_args *vargs)
+{
+	ssize_t err;
+
+	if (!vfsub_ftest(vargs->flags, DLGT)) {
+		vfsub_ignore(vargs);
+		err = do_vfsub_write_k(file, kbuf, count, ppos);
+		if (unlikely(err < 0))
+			vfsub_unignore(vargs);
+	} else {
+		int wkq_err;
+		struct write_args args = {
+			.errp	= &err,
+			.file	= file,
+			.count	= count,
+			.ppos	= ppos,
+			.vargs	= vargs
+		};
+		args.kbuf = kbuf;
+		wkq_err = au_wkq_wait(call_write_k, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+	return err;
+}
+
+struct readdir_args {
+	int *errp;
+	struct file *file;
+	filldir_t filldir;
+	void *arg;
+};
+
+static void call_readdir(void *args)
+{
+	struct readdir_args *a = args;
+	*a->errp = do_vfsub_readdir(a->file, a->filldir, a->arg);
+}
+
+int vfsub_readdir(struct file *file, filldir_t filldir, void *arg, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_readdir(file, filldir, arg);
+	else {
+		int err, wkq_err;
+		struct readdir_args args = {
+			.errp		= &err,
+			.file		= file,
+			.filldir	= filldir,
+			.arg		= arg
+		};
+		wkq_err = au_wkq_wait(call_readdir, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct splice_to_args {
+	long *errp;
+	struct file *in;
+	loff_t *ppos;
+	struct pipe_inode_info *pipe;
+	size_t len;
+	unsigned int flags;
+};
+
+static void call_splice_to(void *args)
+{
+	struct splice_to_args *a = args;
+	*a->errp = do_vfsub_splice_to(a->in, a->ppos, a->pipe, a->len,
+				      a->flags);
+}
+
+long vfsub_splice_to(struct file *in, loff_t *ppos,
+		     struct pipe_inode_info *pipe, size_t len,
+		     unsigned int flags, int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_splice_to(in, ppos, pipe, len, flags);
+	else {
+		long err;
+		int wkq_err;
+		struct splice_to_args args = {
+			.errp	= &err,
+			.in	= in,
+			.ppos	= ppos,
+			.pipe	= pipe,
+			.len	= len,
+			.flags	= flags
+		};
+		wkq_err = au_wkq_wait(call_splice_to, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
+
+struct splice_from_args {
+	long *errp;
+	struct pipe_inode_info *pipe;
+	struct file *out;
+	loff_t *ppos;
+	size_t len;
+	unsigned int flags;
+	struct vfsub_args *vargs;
+};
+
+static void call_splice_from(void *args)
+{
+	struct splice_from_args *a = args;
+	vfsub_ignore(a->vargs);
+	*a->errp = do_vfsub_splice_from(a->pipe, a->out, a->ppos, a->len,
+					a->flags);
+	if (unlikely(*a->errp < 0))
+		vfsub_unignore(a->vargs);
+}
+
+long vfsub_splice_from(struct pipe_inode_info *pipe, struct file *out,
+		       loff_t *ppos, size_t len, unsigned int flags,
+		       struct vfsub_args *vargs)
+{
+	long err;
+
+	if (!vfsub_ftest(vargs->flags, DLGT)) {
+		vfsub_ignore(vargs);
+		err = do_vfsub_splice_from(pipe, out, ppos, len, flags);
+		if (unlikely(err < 0))
+			vfsub_unignore(vargs);
+	} else {
+		int wkq_err;
+		struct splice_from_args args = {
+			.errp	= &err,
+			.pipe	= pipe,
+			.out	= out,
+			.ppos	= ppos,
+			.len	= len,
+			.flags	= flags,
+			.vargs	= vargs
+		};
+		wkq_err = au_wkq_wait(call_splice_from, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+	}
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct getattr_args {
+	int *errp;
+	struct vfsmount *mnt;
+	struct dentry *dentry;
+	struct kstat *st;
+};
+
+static void call_getattr(void *args)
+{
+	struct getattr_args *a = args;
+	*a->errp = do_vfsub_getattr(a->mnt, a->dentry, a->st);
+}
+
+int vfsub_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *st,
+		  int dlgt)
+{
+	if (!dlgt)
+		return do_vfsub_getattr(mnt, dentry, st);
+	else {
+		int err, wkq_err;
+		struct getattr_args args = {
+			.errp	= &err,
+			.mnt	= mnt,
+			.dentry	= dentry,
+			.st	= st
+		};
+		wkq_err = au_wkq_wait(call_getattr, &args, /*dlgt*/1);
+		if (unlikely(wkq_err))
+			err = wkq_err;
+		return err;
+	}
+}
-- 
1.4.4.4