Commit a66b4cd1 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 

Pull vfs open-related updates from Al Viro:

 - "do we need fput() or put_filp()" rules are gone - it's always fput()
   now. We keep track of that state where it belongs - in ->f_mode.

 - int *opened mess killed - in finish_open(), in ->atomic_open()
   instances and in fs/namei.c code around do_last()/lookup_open()/atomic_open().

 - alloc_file() wrappers with saner calling conventions are introduced
   (alloc_file_clone() and alloc_file_pseudo()); callers converted, with
   much simplification.

 - while we are at it, saner calling conventions for path_init() and
   link_path_walk(), simplifying things inside fs/namei.c (both on
   open-related paths and elsewhere).

* 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  few more cleanups of link_path_walk() callers
  allow link_path_walk() to take ERR_PTR()
  make path_init() unconditionally paired with terminate_walk()
  document alloc_file() changes
  make alloc_file() static
  do_shmat(): grab shp->shm_file earlier, switch to alloc_file_clone()
  new helper: alloc_file_clone()
  create_pipe_files(): switch the first allocation to alloc_file_pseudo()
  anon_inode_getfile(): switch to alloc_file_pseudo()
  hugetlb_file_setup(): switch to alloc_file_pseudo()
  ocxlflash_getfile(): switch to alloc_file_pseudo()
  cxl_getfile(): switch to alloc_file_pseudo()
  ... and switch shmem_file_setup() to alloc_file_pseudo()
  __shmem_file_setup(): reorder allocations
  new wrapper: alloc_file_pseudo()
  kill FILE_{CREATED,OPENED}
  switch atomic_open() and lookup_open() to returning 0 in all success cases
  document ->atomic_open() changes
  ->atomic_open(): return 0 in all success cases
  get rid of 'opened' in path_openat() and the helpers downstream
  ...
parents b1652846 5f336e72

Documentation/filesystems/Locking

+1 −1
Original line number Diff line number Diff line
@@ -64,7 +64,7 @@ prototypes: 
	void (*update_time)(struct inode *, struct timespec *, int);

	int (*atomic_open)(struct inode *, struct dentry *,

				struct file *, unsigned open_flag,

				umode_t create_mode, int *opened);

				umode_t create_mode);

	int (*tmpfile) (struct inode *, struct dentry *, umode_t);



locking rules:

Documentation/filesystems/porting

+20 −0
Original line number Diff line number Diff line
@@ -602,3 +602,23 @@ in your dentry operations instead. 
	dentry separately, and it now has request_mask and query_flags arguments

	to specify the fields and sync type requested by statx.  Filesystems not

	supporting any statx-specific features may ignore the new arguments.

--

[mandatory]

	->atomic_open() calling conventions have changed.  Gone is int *opened,

	along with FILE_OPENED/FILE_CREATED.  In place of those we have

	FMODE_OPENED/FMODE_CREATED, set in file->f_mode.  Additionally, return

	value for 'called finish_no_open(), open it yourself' case has become

	0, not 1.  Since finish_no_open() itself is returning 0 now, that part

	does not need any changes in ->atomic_open() instances.

--

[mandatory]

	alloc_file() has become static now; two wrappers are to be used instead.

	alloc_file_pseudo(inode, vfsmount, name, flags, ops) is for the cases

	when dentry needs to be created; that's the majority of old alloc_file()

	users.  Calling conventions: on success a reference to new struct file

	is returned and callers reference to inode is subsumed by that.  On

	failure, ERR_PTR() is returned and no caller's references are affected,

	so the caller needs to drop the inode reference it held.

	alloc_file_clone(file, flags, ops) does not affect any caller's references.

	On success you get a new struct file sharing the mount/dentry with the

	original, on failure - ERR_PTR().

Documentation/filesystems/vfs.txt

+10 −8
Original line number Diff line number Diff line
@@ -386,7 +386,7 @@ struct inode_operations { 
	ssize_t (*listxattr) (struct dentry *, char *, size_t);

	void (*update_time)(struct inode *, struct timespec *, int);

	int (*atomic_open)(struct inode *, struct dentry *, struct file *,

			unsigned open_flag, umode_t create_mode, int *opened);

			unsigned open_flag, umode_t create_mode);

	int (*tmpfile) (struct inode *, struct dentry *, umode_t);

};
@@ -496,13 +496,15 @@ otherwise noted. 


  atomic_open: called on the last component of an open.  Using this optional

  	method the filesystem can look up, possibly create and open the file in

  	one atomic operation.  If it cannot perform this (e.g. the file type

  	turned out to be wrong) it may signal this by returning 1 instead of

	usual 0 or -ve .  This method is only called if the last component is

	negative or needs lookup.  Cached positive dentries are still handled by

	f_op->open().  If the file was created, the FILE_CREATED flag should be

	set in "opened".  In case of O_EXCL the method must only succeed if the

	file didn't exist and hence FILE_CREATED shall always be set on success.

	one atomic operation.  If it wants to leave actual opening to the

	caller (e.g. if the file turned out to be a symlink, device, or just

	something filesystem won't do atomic open for), it may signal this by

	returning finish_no_open(file, dentry).  This method is only called if

	the last component is negative or needs lookup.  Cached positive dentries

	are still handled by f_op->open().  If the file was created,

	FMODE_CREATED flag should be set in file->f_mode.  In case of O_EXCL

	the method must only succeed if the file didn't exist and hence FMODE_CREATED

	shall always be set on success.



  tmpfile: called in the end of O_TMPFILE open().  Optional, equivalent to

	atomically creating, opening and unlinking a file in given directory.

drivers/gpu/drm/drm_lease.c

+1 −1
Original line number Diff line number Diff line
@@ -553,7 +553,7 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev, 


	/* Clone the lessor file to create a new file for us */

	DRM_DEBUG_LEASE("Allocating lease file\n");

	lessee_file = filp_clone_open(lessor_file);

	lessee_file = file_clone_open(lessor_file);

	if (IS_ERR(lessee_file)) {

		ret = PTR_ERR(lessee_file);

		goto out_lessee;

drivers/misc/cxl/api.c

+4 −18
Original line number Diff line number Diff line
@@ -67,10 +67,8 @@ static struct file *cxl_getfile(const char *name, 
				const struct file_operations *fops,

				void *priv, int flags)

{

	struct qstr this;

	struct path path;

	struct file *file;

	struct inode *inode = NULL;

	struct inode *inode;

	int rc;



	/* strongly inspired by anon_inode_getfile() */
@@ -91,23 +89,11 @@ static struct file *cxl_getfile(const char *name, 
		goto err_fs;

	}



	file = ERR_PTR(-ENOMEM);

	this.name = name;

	this.len = strlen(name);

	this.hash = 0;

	path.dentry = d_alloc_pseudo(cxl_vfs_mount->mnt_sb, &this);

	if (!path.dentry)

	file = alloc_file_pseudo(inode, cxl_vfs_mount, name,

				 flags & (O_ACCMODE | O_NONBLOCK), fops);

	if (IS_ERR(file))

		goto err_inode;



	path.mnt = mntget(cxl_vfs_mount);

	d_instantiate(path.dentry, inode);



	file = alloc_file(&path, OPEN_FMODE(flags), fops);

	if (IS_ERR(file)) {

		path_put(&path);

		goto err_fs;

	}

	file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);

	file->private_data = priv;



	return file;

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