open-style analog of vfs_path_lookup() (73d049a4) · Commits · e / devices / android_kernel_xiaomi_markw

arch/um/drivers/mconsole_kern.c

+2 −19

Original line number	Original line	Diff line number	Diff line
	@@ -124,35 +124,18 @@ void mconsole_log(struct mc_request *req)
	#if 0		#if 0
	void mconsole_proc(struct mc_request *req)		void mconsole_proc(struct mc_request *req)
	{		{
	struct nameidata nd;
	struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt;		struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt;
	struct file *file;		struct file *file;
	int n, err;		int n;
	char ptr = req->request.data, buf;		char ptr = req->request.data, buf;
	mm_segment_t old_fs = get_fs();		mm_segment_t old_fs = get_fs();

	ptr += strlen("proc");		ptr += strlen("proc");
	ptr = skip_spaces(ptr);		ptr = skip_spaces(ptr);

	err = vfs_path_lookup(mnt->mnt_root, mnt, ptr, LOOKUP_FOLLOW, &nd);		file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY);
	if (err) {
	mconsole_reply(req, "Failed to look up file", 1, 0);
	goto out;
	}

	err = may_open(&nd.path, MAY_READ, O_RDONLY);
	if (result) {
	mconsole_reply(req, "Failed to open file", 1, 0);
	path_put(&nd.path);
	goto out;
	}

	file = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY,
	current_cred());
	err = PTR_ERR(file);
	if (IS_ERR(file)) {		if (IS_ERR(file)) {
	mconsole_reply(req, "Failed to open file", 1, 0);		mconsole_reply(req, "Failed to open file", 1, 0);
	path_put(&nd.path);
	goto out;		goto out;
	}		}

fs/internal.h

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -114,6 +114,8 @@ struct open_flags {
	};		};
	extern struct file do_filp_open(int dfd, const char pathname,		extern struct file do_filp_open(int dfd, const char pathname,
	const struct open_flags *op, int lookup_flags);		const struct open_flags *op, int lookup_flags);
			extern struct file do_file_open_root(struct dentry , struct vfsmount *,
			const char , const struct open_flags , int lookup_flags);

	/*		/*
	* inode.c		* inode.c

fs/namei.c

+52 −28

Original line number	Original line	Diff line number	Diff line
	@@ -1487,11 +1487,13 @@ static int path_init(int dfd, const char *name, unsigned int flags,
	nd->depth = 0;		nd->depth = 0;
	if (flags & LOOKUP_ROOT) {		if (flags & LOOKUP_ROOT) {
	struct inode *inode = nd->root.dentry->d_inode;		struct inode *inode = nd->root.dentry->d_inode;
			if (*name) {
	if (!inode->i_op->lookup)		if (!inode->i_op->lookup)
	return -ENOTDIR;		return -ENOTDIR;
	retval = inode_permission(inode, MAY_EXEC);		retval = inode_permission(inode, MAY_EXEC);
	if (retval)		if (retval)
	return retval;		return retval;
			}
	nd->path = nd->root;		nd->path = nd->root;
	nd->inode = inode;		nd->inode = inode;
	if (flags & LOOKUP_RCU) {		if (flags & LOOKUP_RCU) {
	@@ -1937,7 +1939,7 @@ int vfs_create(struct inode dir, struct dentry dentry, int mode,
	return error;		return error;
	}		}

	int may_open(struct path *path, int acc_mode, int flag)		static int may_open(struct path *path, int acc_mode, int flag)
	{		{
	struct dentry *dentry = path->dentry;		struct dentry *dentry = path->dentry;
	struct inode *inode = dentry->d_inode;		struct inode *inode = dentry->d_inode;
	@@ -2250,11 +2252,10 @@ exit:
	}		}

	static struct file path_openat(int dfd, const char pathname,		static struct file path_openat(int dfd, const char pathname,
	const struct open_flags *op, int flags)		struct nameidata nd, const struct open_flags op, int flags)
	{		{
	struct file *base = NULL;		struct file *base = NULL;
	struct file *filp;		struct file *filp;
	struct nameidata nd;
	struct path path;		struct path path;
	int count = 0;		int count = 0;
	int error;		int error;
	@@ -2264,27 +2265,27 @@ static struct file path_openat(int dfd, const char pathname,
	return ERR_PTR(-ENFILE);		return ERR_PTR(-ENFILE);

	filp->f_flags = op->open_flag;		filp->f_flags = op->open_flag;
	nd.intent.open.file = filp;		nd->intent.open.file = filp;
	nd.intent.open.flags = open_to_namei_flags(op->open_flag);		nd->intent.open.flags = open_to_namei_flags(op->open_flag);
	nd.intent.open.create_mode = op->mode;		nd->intent.open.create_mode = op->mode;

	error = path_init(dfd, pathname, flags \| LOOKUP_PARENT, &nd, &base);		error = path_init(dfd, pathname, flags \| LOOKUP_PARENT, nd, &base);
	if (unlikely(error))		if (unlikely(error))
	goto out_filp;		goto out_filp;

	current->total_link_count = 0;		current->total_link_count = 0;
	error = link_path_walk(pathname, &nd);		error = link_path_walk(pathname, nd);
	if (unlikely(error))		if (unlikely(error))
	goto out_filp;		goto out_filp;

	filp = do_last(&nd, &path, op, pathname);		filp = do_last(nd, &path, op, pathname);
	while (unlikely(!filp)) { /* trailing symlink */		while (unlikely(!filp)) { /* trailing symlink */
	struct path link = path;		struct path link = path;
	struct inode *linki = link.dentry->d_inode;		struct inode *linki = link.dentry->d_inode;
	void *cookie;		void *cookie;
	if (!(nd.flags & LOOKUP_FOLLOW) \|\| count++ == 32) {		if (!(nd->flags & LOOKUP_FOLLOW) \|\| count++ == 32) {
	path_put_conditional(&path, &nd);		path_put_conditional(&path, nd);
	path_put(&nd.path);		path_put(&nd->path);
	filp = ERR_PTR(-ELOOP);		filp = ERR_PTR(-ELOOP);
	break;		break;
	}		}
	@@ -2299,23 +2300,23 @@ static struct file path_openat(int dfd, const char pathname,
	* have to putname() it when we are done. Procfs-like symlinks		* have to putname() it when we are done. Procfs-like symlinks
	* just set LAST_BIND.		* just set LAST_BIND.
	*/		*/
	nd.flags \|= LOOKUP_PARENT;		nd->flags \|= LOOKUP_PARENT;
	nd.flags &= ~(LOOKUP_OPEN\|LOOKUP_CREATE\|LOOKUP_EXCL);		nd->flags &= ~(LOOKUP_OPEN\|LOOKUP_CREATE\|LOOKUP_EXCL);
	error = __do_follow_link(&link, &nd, &cookie);		error = __do_follow_link(&link, nd, &cookie);
	if (unlikely(error))		if (unlikely(error))
	filp = ERR_PTR(error);		filp = ERR_PTR(error);
	else		else
	filp = do_last(&nd, &path, op, pathname);		filp = do_last(nd, &path, op, pathname);
	if (!IS_ERR(cookie) && linki->i_op->put_link)		if (!IS_ERR(cookie) && linki->i_op->put_link)
	linki->i_op->put_link(link.dentry, &nd, cookie);		linki->i_op->put_link(link.dentry, nd, cookie);
	path_put(&link);		path_put(&link);
	}		}
	out:		out:
	if (nd.root.mnt && !(nd.flags & LOOKUP_ROOT))		if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT))
	path_put(&nd.root);		path_put(&nd->root);
	if (base)		if (base)
	fput(base);		fput(base);
	release_open_intent(&nd);		release_open_intent(nd);
	return filp;		return filp;

	out_filp:		out_filp:
	@@ -2326,16 +2327,39 @@ out_filp:
	struct file do_filp_open(int dfd, const char pathname,		struct file do_filp_open(int dfd, const char pathname,
	const struct open_flags *op, int flags)		const struct open_flags *op, int flags)
	{		{
			struct nameidata nd;
	struct file *filp;		struct file *filp;

	filp = path_openat(dfd, pathname, op, flags \| LOOKUP_RCU);		filp = path_openat(dfd, pathname, &nd, op, flags \| LOOKUP_RCU);
	if (unlikely(filp == ERR_PTR(-ECHILD)))		if (unlikely(filp == ERR_PTR(-ECHILD)))
	filp = path_openat(dfd, pathname, op, flags);		filp = path_openat(dfd, pathname, &nd, op, flags);
	if (unlikely(filp == ERR_PTR(-ESTALE)))		if (unlikely(filp == ERR_PTR(-ESTALE)))
	filp = path_openat(dfd, pathname, op, flags \| LOOKUP_REVAL);		filp = path_openat(dfd, pathname, &nd, op, flags \| LOOKUP_REVAL);
	return filp;		return filp;
	}		}

			struct file do_file_open_root(struct dentry dentry, struct vfsmount *mnt,
			const char name, const struct open_flags op, int flags)
			{
			struct nameidata nd;
			struct file *file;

			nd.root.mnt = mnt;
			nd.root.dentry = dentry;

			flags \|= LOOKUP_ROOT;

			if (dentry->d_inode->i_op->follow_link)
			return ERR_PTR(-ELOOP);

			file = path_openat(-1, name, &nd, op, flags \| LOOKUP_RCU);
			if (unlikely(file == ERR_PTR(-ECHILD)))
			file = path_openat(-1, name, &nd, op, flags);
			if (unlikely(file == ERR_PTR(-ESTALE)))
			file = path_openat(-1, name, &nd, op, flags \| LOOKUP_REVAL);
			return file;
			}

	/**		/**
	* lookup_create - lookup a dentry, creating it if it doesn't exist		* lookup_create - lookup a dentry, creating it if it doesn't exist
	* @nd: nameidata info		* @nd: nameidata info

fs/nfsctl.c

+4 −17

Original line number	Original line	Diff line number	Diff line
	@@ -22,30 +22,17 @@

	static struct file do_open(char name, int flags)		static struct file do_open(char name, int flags)
	{		{
	struct nameidata nd;
	struct vfsmount *mnt;		struct vfsmount *mnt;
	int error;		struct file *file;

	mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);		mnt = do_kern_mount("nfsd", 0, "nfsd", NULL);
	if (IS_ERR(mnt))		if (IS_ERR(mnt))
	return (struct file *)mnt;		return (struct file *)mnt;

	error = vfs_path_lookup(mnt->mnt_root, mnt, name, 0, &nd);		file = file_open_root(mnt->mnt_root, mnt, name, flags);
	mntput(mnt); /* drop do_kern_mount reference */
	if (error)
	return ERR_PTR(error);

	if (flags == O_RDWR)
	error = may_open(&nd.path, MAY_READ\|MAY_WRITE, flags);
	else
	error = may_open(&nd.path, MAY_WRITE, flags);

	if (!error)		mntput(mnt); /* drop do_kern_mount reference */
	return dentry_open(nd.path.dentry, nd.path.mnt, flags,		return file;
	current_cred());

	path_put(&nd.path);
	return ERR_PTR(error);
	}		}

	static struct {		static struct {

fs/open.c

+14 −0

Original line number	Original line	Diff line number	Diff line
	@@ -959,6 +959,20 @@ struct file filp_open(const char filename, int flags, int mode)
	}		}
	EXPORT_SYMBOL(filp_open);		EXPORT_SYMBOL(filp_open);

			struct file file_open_root(struct dentry dentry, struct vfsmount *mnt,
			const char *filename, int flags)
			{
			struct open_flags op;
			int lookup = build_open_flags(flags, 0, &op);
			if (flags & O_CREAT)
			return ERR_PTR(-EINVAL);
			if (!filename && (flags & O_DIRECTORY))
			if (!dentry->d_inode->i_op->lookup)
			return ERR_PTR(-ENOTDIR);
			return do_file_open_root(dentry, mnt, filename, &op, lookup);
			}
			EXPORT_SYMBOL(file_open_root);

	long do_sys_open(int dfd, const char __user *filename, int flags, int mode)		long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
	{		{
	struct open_flags op;		struct open_flags op;