Re: [PATCH v5 03/10] DMA reservations: use the new mmap locking API

From: Vlastimil Babka
Date: Mon May 18 2020 - 05:30:03 EST


On 4/22/20 2:14 AM, Michel Lespinasse wrote:
> This use is converted manually ahead of the next patch in the series,
> as it requires including a new header which the automated conversion
> would miss.
>
> Signed-off-by: Michel Lespinasse <walken@xxxxxxxxxx>
> Reviewed-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>

Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>

---
> drivers/dma-buf/dma-resv.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
> index 4264e64788c4..b45f8514dc82 100644
> --- a/drivers/dma-buf/dma-resv.c
> +++ b/drivers/dma-buf/dma-resv.c
> @@ -34,6 +34,7 @@
>
> #include <linux/dma-resv.h>
> #include <linux/export.h>
> +#include <linux/mm.h>
> #include <linux/sched/mm.h>
>
> /**
> @@ -109,7 +110,7 @@ static int __init dma_resv_lockdep(void)
>
> dma_resv_init(&obj);
>
> - down_read(&mm->mmap_sem);
> + mmap_read_lock(mm);
> ww_acquire_init(&ctx, &reservation_ww_class);
> ret = dma_resv_lock(&obj, &ctx);
> if (ret == -EDEADLK)
> @@ -118,7 +119,7 @@ static int __init dma_resv_lockdep(void)
> fs_reclaim_release(GFP_KERNEL);
> ww_mutex_unlock(&obj.lock);
> ww_acquire_fini(&ctx);
> - up_read(&mm->mmap_sem);
> + mmap_read_unlock(mm);
>
> mmput(mm);
>
>