C++ (Cpp) vfs_iter_write Examples

Example #1

File: loop.c Project: alex-deng/debian_kernel_allwinner_a33

static int lo_write_bvec(struct file *file, struct bio_vec *bvec, loff_t *ppos)
{
	struct iov_iter i;
	ssize_t bw;

	iov_iter_bvec(&i, ITER_BVEC, bvec, 1, bvec->bv_len);

	file_start_write(file);
	bw = vfs_iter_write(file, &i, ppos);
	file_end_write(file);

	if (likely(bw ==  bvec->bv_len))
		return 0;

	printk_ratelimited(KERN_ERR
		"loop: Write error at byte offset %llu, length %i.\n",
		(unsigned long long)*ppos, bvec->bv_len);
	if (bw >= 0)
		bw = -EIO;
	return bw;
}

Example #2

File: file.c Project: Lyude/linux

static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
{
	struct file *file = iocb->ki_filp;
	struct inode *inode = file_inode(file);
	struct fd real;
	const struct cred *old_cred;
	ssize_t ret;

	if (!iov_iter_count(iter))
		return 0;

	inode_lock(inode);
	/* Update mode */
	ovl_copyattr(ovl_inode_real(inode), inode);
	ret = file_remove_privs(file);
	if (ret)
		goto out_unlock;

	ret = ovl_real_fdget(file, &real);
	if (ret)
		goto out_unlock;

	old_cred = ovl_override_creds(file_inode(file)->i_sb);
	file_start_write(real.file);
	ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,
			     ovl_iocb_to_rwf(iocb));
	file_end_write(real.file);
	revert_creds(old_cred);

	/* Update size */
	ovl_copyattr(ovl_inode_real(inode), inode);

	fdput(real);

out_unlock:
	inode_unlock(inode);

	return ret;
}

Example #3

File: file.c Project: AshishNamdev/linux

static ssize_t
coda_file_write_iter(struct kiocb *iocb, struct iov_iter *to)
{
	struct file *coda_file = iocb->ki_filp;
	struct inode *coda_inode = file_inode(coda_file);
	struct coda_file_info *cfi = CODA_FTOC(coda_file);
	struct file *host_file;
	ssize_t ret;

	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);

	host_file = cfi->cfi_container;
	file_start_write(host_file);
	inode_lock(coda_inode);
	ret = vfs_iter_write(cfi->cfi_container, to, &iocb->ki_pos);
	coda_inode->i_size = file_inode(host_file)->i_size;
	coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9;
	coda_inode->i_mtime = coda_inode->i_ctime = current_time(coda_inode);
	inode_unlock(coda_inode);
	file_end_write(host_file);
	return ret;
}