Unverified Commit 50166d57 authored by Christian Brauner's avatar Christian Brauner
Browse files

exportfs: add open method 

This allows filesystems such as pidfs to provide their custom open.

Link: https://lore.kernel.org/r/20241129-work-pidfs-file_handle-v1-3-87d803a42495@kernel.org


Reviewed-by: default avatarAmir Goldstein <amir73il@gmail.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent f07c7cc4

fs/fhandle.c

+6 −1
Original line number Diff line number Diff line
@@ -401,6 +401,7 @@ static long do_handle_open(int mountdirfd, struct file_handle __user *ufh, 
	long retval = 0;

	struct path path __free(path_put) = {};

	struct file *file;

	const struct export_operations *eops;



	retval = handle_to_path(mountdirfd, ufh, &path, open_flag);

	if (retval)
@@ -410,6 +411,10 @@ static long do_handle_open(int mountdirfd, struct file_handle __user *ufh, 
	if (fd < 0)

		return fd;



	eops = path.mnt->mnt_sb->s_export_op;

	if (eops->open)

		file = eops->open(&path, open_flag);

	else

		file = file_open_root(&path, "", open_flag, 0);

	if (IS_ERR(file))

		return PTR_ERR(file);

include/linux/exportfs.h

+5 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ struct inode; 
struct iomap;

struct super_block;

struct vfsmount;

struct path;



/* limit the handle size to NFSv4 handle size now */

#define MAX_HANDLE_SZ 128
@@ -225,6 +226,9 @@ struct fid { 
 *    is also a directory.  In the event that it cannot be found, or storage

 *    space cannot be allocated, a %ERR_PTR should be returned.

 *

 * open:

 *    Allow filesystems to specify a custom open function.

 *

 * commit_metadata:

 *    @commit_metadata should commit metadata changes to stable storage.

 *
@@ -251,6 +255,7 @@ struct export_operations { 
			  bool write, u32 *device_generation);

	int (*commit_blocks)(struct inode *inode, struct iomap *iomaps,

			     int nr_iomaps, struct iattr *iattr);

	struct file * (*open)(struct path *path, unsigned int oflags);

#define	EXPORT_OP_NOWCC			(0x1) /* don't collect v3 wcc data */

#define	EXPORT_OP_NOSUBTREECHK		(0x2) /* no subtree checking */

#define	EXPORT_OP_CLOSE_BEFORE_UNLINK	(0x4) /* close files before unlink */