patch "staging: ion: Fix ion_cma_heap allocations" added to staging-linus

patch "staging: ion: Fix ion_cma_heap allocations" added to staging-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    staging: ion: Fix ion_cma_heap allocations

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From d98e6dbf42f73101128885a1e0ae672cd92b2e1a Mon Sep 17 00:00:00 2001
From: John Stultz <john.stultz@linaro.org>
Date: Fri, 8 Dec 2017 17:11:12 -0800
Subject: staging: ion: Fix ion_cma_heap allocations

In trying to add support for drm_hwcomposer to HiKey,
I've needed to utilize the ION CMA heap, and I've noticed
problems with allocations on newer kernels failing.

It seems back with 204f672255c2 ("ion: Use CMA APIs directly"),
the ion_cma_heap code was modified to use the CMA API, but
kept the arguments as buffer lengths rather then number of pages.

This results in errors as we don't have enough pages in CMA to
satisfy the exaggerated requests.

This patch converts the ion_cma_heap CMA API usage to properly
request pages.

It also fixes a minor issue in the allocation where in the error
path, the cma_release is called with the buffer->size value which
hasn't yet been set.

Cc: Laura Abbott <labbott@redhat.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dmitry Shmidt <dimitrysh@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Amit Pundir <amit.pundir@linaro.org>
Fixes: 204f672255c2 ("staging: android: ion: Use CMA APIs directly")
Cc: stable <stable@vger.kernel.org>
Acked-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/staging/android/ion/ion_cma_heap.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/android/ion/ion_cma_heap.c b/drivers/staging/android/ion/ion_cma_heap.c
index dd5545d9990a..86196ffd2faf 100644
--- a/drivers/staging/android/ion/ion_cma_heap.c
+++ b/drivers/staging/android/ion/ion_cma_heap.c
@@ -39,9 +39,15 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
 	struct ion_cma_heap *cma_heap = to_cma_heap(heap);
 	struct sg_table *table;
 	struct page *pages;
+	unsigned long size = PAGE_ALIGN(len);
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	unsigned long align = get_order(size);
 	int ret;
 
-	pages = cma_alloc(cma_heap->cma, len, 0, GFP_KERNEL);
+	if (align > CONFIG_CMA_ALIGNMENT)
+		align = CONFIG_CMA_ALIGNMENT;
+
+	pages = cma_alloc(cma_heap->cma, nr_pages, align, GFP_KERNEL);
 	if (!pages)
 		return -ENOMEM;
 
@@ -53,7 +59,7 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
 	if (ret)
 		goto free_mem;
 
-	sg_set_page(table->sgl, pages, len, 0);
+	sg_set_page(table->sgl, pages, size, 0);
 
 	buffer->priv_virt = pages;
 	buffer->sg_table = table;
@@ -62,7 +68,7 @@ static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
 free_mem:
 	kfree(table);
 err:
-	cma_release(cma_heap->cma, pages, buffer->size);
+	cma_release(cma_heap->cma, pages, nr_pages);
 	return -ENOMEM;
 }
 
@@ -70,9 +76,10 @@ static void ion_cma_free(struct ion_buffer *buffer)
 {
 	struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 	struct page *pages = buffer->priv_virt;
+	unsigned long nr_pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
 
 	/* release memory */
-	cma_release(cma_heap->cma, pages, buffer->size);
+	cma_release(cma_heap->cma, pages, nr_pages);
 	/* release sg table */
 	sg_free_table(buffer->sg_table);
 	kfree(buffer->sg_table);
-- 
2.15.1