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        <ckoenig.leichtzumerken@gmail.com>
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Cc:     christian.koenig@amd.com, alexander.deucher@amd.com,
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Subject: [PATCH 04/13] dma-buf: provide oom badness for DMA-buf files
Date:   Tue, 31 May 2022 11:59:58 +0200
Message-Id: <20220531100007.174649-5-christian.koenig@amd.com>
In-Reply-To: <20220531100007.174649-1-christian.koenig@amd.com>
References: <20220531100007.174649-1-christian.koenig@amd.com>
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Precedence: bulk

For now just return the size of the DMA-buf in pages as badness in the
OOM situation. That should probably be extended to be in control of the
exporter in the future.

Signed-off-by: Christian König <christian.koenig@amd.com>
---
 drivers/dma-buf/dma-buf.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index a2f9a1815e38..bdd4e8767cd3 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -388,6 +388,12 @@ static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file)
 	spin_unlock(&dmabuf->name_lock);
 }
 
+static long dma_buf_oom_badness(struct file *file)
+{
+	/* TODO: This should probably be controlled by a flag */
+	return i_size_read(file_inode(file)) >> PAGE_SHIFT;
+}
+
 static const struct file_operations dma_buf_fops = {
 	.release	= dma_buf_file_release,
 	.mmap		= dma_buf_mmap_internal,
@@ -396,6 +402,7 @@ static const struct file_operations dma_buf_fops = {
 	.unlocked_ioctl	= dma_buf_ioctl,
 	.compat_ioctl	= compat_ptr_ioctl,
 	.show_fdinfo	= dma_buf_show_fdinfo,
+	.oom_badness	= dma_buf_oom_badness,
 };
 
 /*
-- 
2.25.1