Commit 63ed1e02 authored by Souptick Joarder's avatar Souptick Joarder Committed by Greg Kroah-Hartman
Browse files

staging: kpc2000: kpc_dma: Unpin partial pinned pages 



There is a bug, when get_user_pages() failed but partially pinned
pages are not unpinned and positive numbers are returned instead of
-ERRNO. Fixed it.

Also, int is more appropriate type for rv. Changed it.

Signed-off-by: default avatarSouptick Joarder <jrdr.linux@gmail.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Bharath Vedartham <linux.bhar@gmail.com>
Link: https://lore.kernel.org/r/1593584264-16982-2-git-send-email-jrdr.linux@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f9b468a3

drivers/staging/kpc2000/kpc_dma/fileops.c

+9 −4
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ static int kpc_dma_transfer(struct dev_private_data *priv, 
			    unsigned long iov_base, size_t iov_len)

{

	unsigned int i = 0;

	long rv = 0;

	int rv = 0;

	struct kpc_dma_device *ldev;

	struct aio_cb_data *acd;

	DECLARE_COMPLETION_ONSTACK(done);
@@ -79,14 +79,14 @@ static int kpc_dma_transfer(struct dev_private_data *priv, 
	rv = get_user_pages(iov_base, acd->page_count, FOLL_TOUCH | FOLL_WRITE | FOLL_GET, acd->user_pages, NULL);

	mmap_read_unlock(current->mm);        /*  release the semaphore */

	if (rv != acd->page_count) {

		dev_err(&priv->ldev->pldev->dev, "Couldn't get_user_pages (%ld)\n", rv);

		dev_err(&priv->ldev->pldev->dev, "Couldn't get_user_pages (%d)\n", rv);

		goto err_get_user_pages;

	}



	// Allocate and setup the sg_table (scatterlist entries)

	rv = sg_alloc_table_from_pages(&acd->sgt, acd->user_pages, acd->page_count, iov_base & (PAGE_SIZE - 1), iov_len, GFP_KERNEL);

	if (rv) {

		dev_err(&priv->ldev->pldev->dev, "Couldn't alloc sg_table (%ld)\n", rv);

		dev_err(&priv->ldev->pldev->dev, "Couldn't alloc sg_table (%d)\n", rv);

		goto err_alloc_sg_table;

	}
@@ -193,10 +193,15 @@ static int kpc_dma_transfer(struct dev_private_data *priv, 
		put_page(acd->user_pages[i]);



 err_get_user_pages:

	if (rv > 0) {

		for (i = 0; i < rv; i++)

			put_pages(acd->user_pages[i]);

		rv = -EFAULT;

	}

	kfree(acd->user_pages);

 err_alloc_userpages:

	kfree(acd);

	dev_dbg(&priv->ldev->pldev->dev, "%s returning with error %ld\n", __func__, rv);

	dev_dbg(&priv->ldev->pldev->dev, "%s returning with error %d\n", __func__, rv);

	return rv;

}

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