Commit 1b5dd298 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs 

Pull fd prepare updates from Christian Brauner:
 "This adds the FD_ADD() and FD_PREPARE() primitive. They simplify the
  common pattern of get_unused_fd_flags() + create file + fd_install()
  that is used extensively throughout the kernel and currently requires
  cumbersome cleanup paths.

  FD_ADD() - For simple cases where a file is installed immediately:

      fd = FD_ADD(O_CLOEXEC, vfio_device_open_file(device));
      if (fd < 0)
          vfio_device_put_registration(device);
      return fd;

  FD_PREPARE() - For cases requiring access to the fd or file, or
  additional work before publishing:

      FD_PREPARE(fdf, O_CLOEXEC, sync_file->file);
      if (fdf.err) {
          fput(sync_file->file);
          return fdf.err;
      }

      data.fence = fd_prepare_fd(fdf);
      if (copy_to_user((void __user *)arg, &data, sizeof(data)))
          return -EFAULT;

      return fd_publish(fdf);

  The primitives are centered around struct fd_prepare. FD_PREPARE()
  encapsulates all allocation and cleanup logic and must be followed by
  a call to fd_publish() which associates the fd with the file and
  installs it into the caller's fdtable. If fd_publish() isn't called,
  both are deallocated automatically. FD_ADD() is a shorthand that does
  fd_publish() immediately and never exposes the struct to the caller.

  I've implemented this in a way that it's compatible with the cleanup
  infrastructure while also being usable separately. IOW, it's centered
  around struct fd_prepare which is aliased to class_fd_prepare_t and so
  we can make use of all the basica guard infrastructure"

* tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits)
  io_uring: convert io_create_mock_file() to FD_PREPARE()
  file: convert replace_fd() to FD_PREPARE()
  vfio: convert vfio_group_ioctl_get_device_fd() to FD_ADD()
  tty: convert ptm_open_peer() to FD_ADD()
  ntsync: convert ntsync_obj_get_fd() to FD_PREPARE()
  media: convert media_request_alloc() to FD_PREPARE()
  hv: convert mshv_ioctl_create_partition() to FD_ADD()
  gpio: convert linehandle_create() to FD_PREPARE()
  pseries: port papr_rtas_setup_file_interface() to FD_ADD()
  pseries: convert papr_platform_dump_create_handle() to FD_ADD()
  spufs: convert spufs_gang_open() to FD_PREPARE()
  papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE()
  spufs: convert spufs_context_open() to FD_PREPARE()
  net/socket: convert __sys_accept4_file() to FD_ADD()
  net/socket: convert sock_map_fd() to FD_ADD()
  net/kcm: convert kcm_ioctl() to FD_PREPARE()
  net/handshake: convert handshake_nl_accept_doit() to FD_PREPARE()
  secretmem: convert memfd_secret() to FD_ADD()
  memfd: convert memfd_create() to FD_ADD()
  bpf: convert bpf_token_create() to FD_PREPARE()
  ...
parents ffbf700d 0512bf97

arch/powerpc/platforms/cell/spufs/inode.c

+10 −32
Original line number Diff line number Diff line
@@ -267,22 +267,11 @@ spufs_mkdir(struct inode *dir, struct dentry *dentry, unsigned int flags, 


static int spufs_context_open(const struct path *path)

{

	int ret;

	struct file *filp;



	ret = get_unused_fd_flags(0);

	if (ret < 0)

		return ret;



	filp = dentry_open(path, O_RDONLY, current_cred());

	if (IS_ERR(filp)) {

		put_unused_fd(ret);

		return PTR_ERR(filp);

	}



	filp->f_op = &spufs_context_fops;

	fd_install(ret, filp);

	return ret;

	FD_PREPARE(fdf, 0, dentry_open(path, O_RDONLY, current_cred()));

	if (fdf.err)

		return fdf.err;

	fd_prepare_file(fdf)->f_op = &spufs_context_fops;

	return fd_publish(fdf);

}



static struct spu_context *
@@ -508,26 +497,15 @@ static const struct file_operations spufs_gang_fops = { 


static int spufs_gang_open(const struct path *path)

{

	int ret;

	struct file *filp;



	ret = get_unused_fd_flags(0);

	if (ret < 0)

		return ret;



	/*

	 * get references for dget and mntget, will be released

	 * in error path of *_open().

	 */

	filp = dentry_open(path, O_RDONLY, current_cred());

	if (IS_ERR(filp)) {

		put_unused_fd(ret);

		return PTR_ERR(filp);

	}



	filp->f_op = &spufs_gang_fops;

	fd_install(ret, filp);

	return ret;

	FD_PREPARE(fdf, 0, dentry_open(path, O_RDONLY, current_cred()));

	if (fdf.err)

		return fdf.err;

	fd_prepare_file(fdf)->f_op = &spufs_gang_fops;

	return fd_publish(fdf);

}



static int spufs_create_gang(struct inode *inode,

arch/powerpc/platforms/pseries/papr-hvpipe.c

+9 −30
Original line number Diff line number Diff line
@@ -479,10 +479,7 @@ static const struct file_operations papr_hvpipe_handle_ops = { 


static int papr_hvpipe_dev_create_handle(u32 srcID)

{

	struct hvpipe_source_info *src_info;

	struct file *file;

	long err;

	int fd;

	struct hvpipe_source_info *src_info __free(kfree) = NULL;



	spin_lock(&hvpipe_src_list_lock);

	/*
@@ -506,20 +503,13 @@ static int papr_hvpipe_dev_create_handle(u32 srcID) 
	src_info->tsk = current;

	init_waitqueue_head(&src_info->recv_wqh);



	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);

	if (fd < 0) {

		err = fd;

		goto free_buf;

	}



	file = anon_inode_getfile("[papr-hvpipe]",

			&papr_hvpipe_handle_ops, (void *)src_info,

			O_RDWR);

	if (IS_ERR(file)) {

		err = PTR_ERR(file);

		goto free_fd;

	}

	FD_PREPARE(fdf, O_RDONLY | O_CLOEXEC,

		   anon_inode_getfile("[papr-hvpipe]", &papr_hvpipe_handle_ops,

				      (void *)src_info, O_RDWR));

	if (fdf.err)

		return fdf.err;



	retain_and_null_ptr(src_info);

	spin_lock(&hvpipe_src_list_lock);

	/*

	 * If two processes are executing ioctl() for the same
@@ -528,22 +518,11 @@ static int papr_hvpipe_dev_create_handle(u32 srcID) 
	 */

	if (hvpipe_find_source(srcID)) {

		spin_unlock(&hvpipe_src_list_lock);

		err = -EALREADY;

		goto free_file;

		return -EALREADY;

	}

	list_add(&src_info->list, &hvpipe_src_list);

	spin_unlock(&hvpipe_src_list_lock);



	fd_install(fd, file);

	return fd;



free_file:

	fput(file);

free_fd:

	put_unused_fd(fd);

free_buf:

	kfree(src_info);

	return err;

	return fd_publish(fdf);

}



/*

arch/powerpc/platforms/pseries/papr-platform-dump.c

+8 −22
Original line number Diff line number Diff line
@@ -303,8 +303,6 @@ static long papr_platform_dump_create_handle(u64 dump_tag) 
{

	struct ibm_platform_dump_params *params;

	u64 param_dump_tag;

	struct file *file;

	long err;

	int fd;



	/*
@@ -334,34 +332,22 @@ static long papr_platform_dump_create_handle(u64 dump_tag) 
	params->dump_tag_lo = (u32)(dump_tag & 0x00000000ffffffffULL);

	params->status = RTAS_IBM_PLATFORM_DUMP_START;



	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);

	if (fd < 0) {

		err = fd;

		goto free_area;

	}



	file = anon_inode_getfile_fmode("[papr-platform-dump]",

	fd = FD_ADD(O_RDONLY | O_CLOEXEC,

		    anon_inode_getfile_fmode("[papr-platform-dump]",

					     &papr_platform_dump_handle_ops,

					     (void *)params, O_RDONLY,

				FMODE_LSEEK | FMODE_PREAD);

	if (IS_ERR(file)) {

		err = PTR_ERR(file);

		goto put_fd;

					     FMODE_LSEEK | FMODE_PREAD));

	if (fd < 0) {

		rtas_work_area_free(params->work_area);

		kfree(params);

		return fd;

	}



	fd_install(fd, file);



	list_add(&params->list, &platform_dump_list);



	pr_info("%s (%d) initiated platform dump for dump tag %llu\n",

		current->comm, current->pid, dump_tag);

	return fd;

put_fd:

	put_unused_fd(fd);

free_area:

	rtas_work_area_free(params->work_area);

	kfree(params);

	return err;

}



/*

arch/powerpc/platforms/pseries/papr-rtas-common.c

+5 −22
Original line number Diff line number Diff line
@@ -205,35 +205,18 @@ long papr_rtas_setup_file_interface(struct papr_rtas_sequence *seq, 
				char *name)

{

	const struct papr_rtas_blob *blob;

	struct file *file;

	long ret;

	int fd;



	blob = papr_rtas_retrieve(seq);

	if (IS_ERR(blob))

		return PTR_ERR(blob);



	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);

	if (fd < 0) {

		ret = fd;

		goto free_blob;

	}



	file = anon_inode_getfile_fmode(name, fops, (void *)blob,

			O_RDONLY, FMODE_LSEEK | FMODE_PREAD);

	if (IS_ERR(file)) {

		ret = PTR_ERR(file);

		goto put_fd;

	}



	fd_install(fd, file);

	return fd;



put_fd:

	put_unused_fd(fd);

free_blob:

	fd = FD_ADD(O_RDONLY | O_CLOEXEC,

		   anon_inode_getfile_fmode(name, fops, (void *)blob, O_RDONLY,

					    FMODE_LSEEK | FMODE_PREAD));

	if (fd < 0)

		papr_rtas_blob_free(blob);

	return ret;

	return fd;

}



/*

drivers/dma-buf/dma-buf.c

+1 −9
Original line number Diff line number Diff line
@@ -768,18 +768,10 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_export, "DMA_BUF"); 
 */

int dma_buf_fd(struct dma_buf *dmabuf, int flags)

{

	int fd;



	if (!dmabuf || !dmabuf->file)

		return -EINVAL;



	fd = get_unused_fd_flags(flags);

	if (fd < 0)

		return fd;



	fd_install(fd, dmabuf->file);



	return fd;

	return FD_ADD(flags, dmabuf->file);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_fd, "DMA_BUF");