2019-07-18 06:54:58

by Juergen Gross

[permalink] [raw]
Subject: [PATCH 0/2] xen/gntdev: sanitize user interface handling

The Xen gntdev driver's checking of the number of allowed mapped pages
is in need of some sanitizing work.

Juergen Gross (2):
xen/gntdev: replace global limit of mapped pages by limit per call
xen/gntdev: switch from kcalloc() to kvcalloc()

drivers/xen/gntdev-common.h | 2 +-
drivers/xen/gntdev-dmabuf.c | 11 +++-------
drivers/xen/gntdev.c | 52 ++++++++++++++++++---------------------------
3 files changed, 25 insertions(+), 40 deletions(-)

--
2.16.4


2019-07-18 06:55:04

by Juergen Gross

[permalink] [raw]
Subject: [PATCH 2/2] xen/gntdev: switch from kcalloc() to kvcalloc()

With sufficient many pages to map gntdev can reach order 9 allocation
sizes. As there is no need to have physically contiguous buffers switch
to kvcalloc() in order to avoid failing allocations.

Signed-off-by: Juergen Gross <[email protected]>
---
drivers/xen/gntdev.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 23e21a9aedf7..961aa778312b 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -115,14 +115,14 @@ static void gntdev_free_map(struct gntdev_grant_map *map)
gnttab_free_pages(map->count, map->pages);

#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
- kfree(map->frames);
+ kvfree(map->frames);
#endif
- kfree(map->pages);
- kfree(map->grants);
- kfree(map->map_ops);
- kfree(map->unmap_ops);
- kfree(map->kmap_ops);
- kfree(map->kunmap_ops);
+ kvfree(map->pages);
+ kvfree(map->grants);
+ kvfree(map->map_ops);
+ kvfree(map->unmap_ops);
+ kvfree(map->kmap_ops);
+ kvfree(map->kunmap_ops);
kfree(map);
}

@@ -136,12 +136,12 @@ struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
if (NULL == add)
return NULL;

- add->grants = kcalloc(count, sizeof(add->grants[0]), GFP_KERNEL);
- add->map_ops = kcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL);
- add->unmap_ops = kcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL);
- add->kmap_ops = kcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL);
- add->kunmap_ops = kcalloc(count, sizeof(add->kunmap_ops[0]), GFP_KERNEL);
- add->pages = kcalloc(count, sizeof(add->pages[0]), GFP_KERNEL);
+ add->grants = kvcalloc(count, sizeof(add->grants[0]), GFP_KERNEL);
+ add->map_ops = kvcalloc(count, sizeof(add->map_ops[0]), GFP_KERNEL);
+ add->unmap_ops = kvcalloc(count, sizeof(add->unmap_ops[0]), GFP_KERNEL);
+ add->kmap_ops = kvcalloc(count, sizeof(add->kmap_ops[0]), GFP_KERNEL);
+ add->kunmap_ops = kvcalloc(count, sizeof(add->kunmap_ops[0]), GFP_KERNEL);
+ add->pages = kvcalloc(count, sizeof(add->pages[0]), GFP_KERNEL);
if (NULL == add->grants ||
NULL == add->map_ops ||
NULL == add->unmap_ops ||
@@ -160,8 +160,8 @@ struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
if (dma_flags & (GNTDEV_DMA_FLAG_WC | GNTDEV_DMA_FLAG_COHERENT)) {
struct gnttab_dma_alloc_args args;

- add->frames = kcalloc(count, sizeof(add->frames[0]),
- GFP_KERNEL);
+ add->frames = kvcalloc(count, sizeof(add->frames[0]),
+ GFP_KERNEL);
if (!add->frames)
goto err;

--
2.16.4

2019-07-18 10:04:09

by Oleksandr Andrushchenko

[permalink] [raw]
Subject: Re: [Xen-devel] [PATCH 0/2] xen/gntdev: sanitize user interface handling

On 7/18/19 9:52 AM, Juergen Gross wrote:
> The Xen gntdev driver's checking of the number of allowed mapped pages
> is in need of some sanitizing work.
>
> Juergen Gross (2):
> xen/gntdev: replace global limit of mapped pages by limit per call
> xen/gntdev: switch from kcalloc() to kvcalloc()
>
> drivers/xen/gntdev-common.h | 2 +-
> drivers/xen/gntdev-dmabuf.c | 11 +++-------
> drivers/xen/gntdev.c | 52 ++++++++++++++++++---------------------------
> 3 files changed, 25 insertions(+), 40 deletions(-)
>
For the series:
Reviewed-by: Oleksandr Andrushchenko <[email protected]>