From 313abe55a87bc10e55d00f337d609e17ad5f8c9a Mon Sep 17 00:00:00 2001
From: Jack Morgenstein <jackm@dev.mellanox.co.il>
Date: Mon, 28 Jan 2008 10:40:51 +0200
Subject: [PATCH] mlx4_core: For 64-bit systems, vmap() kernel queue buffers
Since kernel virtual memory is not a problem on 64-bit systems, there
is no reason to use our own 2-layer page mapping scheme for large
kernel queue buffers on such systems. Instead, map the page list to a
single virtually contiguous buffer with vmap(), so that can we access
buffer memory via direct indexing.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
---
drivers/net/mlx4/alloc.c | 16 ++++++++++++++++
include/linux/mlx4/device.h | 4 ++--
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/net/mlx4/alloc.c b/drivers/net/mlx4/alloc.c
index b226e019bc8b7..2da2c2ec1f224 100644
--- a/drivers/net/mlx4/alloc.c
+++ b/drivers/net/mlx4/alloc.c
@@ -151,6 +151,19 @@ int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct,
memset(buf->u.page_list[i].buf, 0, PAGE_SIZE);
}
+
+ if (BITS_PER_LONG == 64) {
+ struct page **pages;
+ pages = kmalloc(sizeof *pages * buf->nbufs, GFP_KERNEL);
+ if (!pages)
+ goto err_free;
+ for (i = 0; i < buf->nbufs; ++i)
+ pages[i] = virt_to_page(buf->u.page_list[i].buf);
+ buf->u.direct.buf = vmap(pages, buf->nbufs, VM_MAP, PAGE_KERNEL);
+ kfree(pages);
+ if (!buf->u.direct.buf)
+ goto err_free;
+ }
}
return 0;
@@ -170,6 +183,9 @@ void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf)
dma_free_coherent(&dev->pdev->dev, size, buf->u.direct.buf,
buf->u.direct.map);
else {
+ if (BITS_PER_LONG == 64)
+ vunmap(buf->u.direct.buf);
+
for (i = 0; i < buf->nbufs; ++i)
if (buf->u.page_list[i].buf)
dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index a0afa7511a30a..631607788f83e 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -189,7 +189,7 @@ struct mlx4_buf_list {
};
struct mlx4_buf {
- union {
+ struct {
struct mlx4_buf_list direct;
struct mlx4_buf_list *page_list;
} u;
@@ -310,7 +310,7 @@ int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct,
void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf);
static inline void *mlx4_buf_offset(struct mlx4_buf *buf, int offset)
{
- if (buf->nbufs == 1)
+ if (BITS_PER_LONG == 64 || buf->nbufs == 1)
return buf->u.direct.buf + offset;
else
return buf->u.page_list[offset >> PAGE_SHIFT].buf +
--
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