From 95154990a7ae05cef093459b0dd038f12dcd7034 Mon Sep 17 00:00:00 2001 From: Souptick Joarder Date: Wed, 1 Jul 2020 11:47:44 +0530 Subject: staging: kpc2000: kpc_dma: Remove additional goto statements As 3 goto level referring to same common code, those can be accomodated with a single goto level and renameing it to unpin_pages. Set the -ERRNO when returning partial mapped pages in more appropriate place. When dma_map_sg() failed, the previously allocated memory was not freed properly. This is corrected now. Signed-off-by: Souptick Joarder Cc: John Hubbard Cc: Bharath Vedartham Cc: Dan Carpenter Link: https://lore.kernel.org/r/1593584264-16982-5-git-send-email-jrdr.linux@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/kpc2000/kpc_dma/fileops.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) (limited to 'drivers/staging') diff --git a/drivers/staging/kpc2000/kpc_dma/fileops.c b/drivers/staging/kpc2000/kpc_dma/fileops.c index 8cd20adea91c..dd716edd9b1b 100644 --- a/drivers/staging/kpc2000/kpc_dma/fileops.c +++ b/drivers/staging/kpc2000/kpc_dma/fileops.c @@ -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; - int rv = 0; + int rv = 0, nr_pages = 0; struct kpc_dma_device *ldev; struct aio_cb_data *acd; DECLARE_COMPLETION_ONSTACK(done); @@ -79,22 +79,27 @@ static int kpc_dma_transfer(struct dev_private_data *priv, rv = pin_user_pages(iov_base, acd->page_count, FOLL_TOUCH | FOLL_WRITE, acd->user_pages, NULL); mmap_read_unlock(current->mm); /* release the semaphore */ if (rv != acd->page_count) { + nr_pages = rv; + if (rv > 0) + rv = -EFAULT; + dev_err(&priv->ldev->pldev->dev, "Couldn't pin_user_pages (%d)\n", rv); - goto err_get_user_pages; + goto unpin_pages; } + nr_pages = acd->page_count; // 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 (%d)\n", rv); - goto err_alloc_sg_table; + goto unpin_pages; } // Setup the DMA mapping for all the sg entries acd->mapped_entry_count = dma_map_sg(&ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents, ldev->dir); if (acd->mapped_entry_count <= 0) { dev_err(&priv->ldev->pldev->dev, "Couldn't dma_map_sg (%d)\n", acd->mapped_entry_count); - goto err_dma_map_sg; + goto free_table; } // Calculate how many descriptors are actually needed for this transfer. @@ -186,16 +191,12 @@ static int kpc_dma_transfer(struct dev_private_data *priv, err_descr_too_many: unlock_engine(ldev); dma_unmap_sg(&ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents, ldev->dir); + free_table: sg_free_table(&acd->sgt); - err_dma_map_sg: - err_alloc_sg_table: - unpin_user_pages(acd->user_pages, acd->page_count); - err_get_user_pages: - if (rv > 0) { - unpin_user_pages(acd->user_pages, rv); - rv = -EFAULT; - } + unpin_pages: + if (nr_pages > 0) + unpin_user_pages(acd->user_pages, nr_pages); kfree(acd->user_pages); err_alloc_userpages: kfree(acd); -- cgit v1.2.3-59-g8ed1b