net/mlx5_core,mlx5_ib: Do not use vmap() on coherent memory

As David Daney pointed in mlx4_core driver [1], mlx5_core is also
misusing the DMA-API.

This patch is removing the code that vmap() memory allocated by
dma_alloc_coherent().

After this patch, users of this drivers might fail allocating resources
on memory fragmeneted systems.  This will be fixed later on.

[1] - https://patchwork.ozlabs.org/patch/458531/

CC: David Daney <david.daney@cavium.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/infiniband/hw/mlx5/cq.c b/drivers/infiniband/hw/mlx5/cq.c
index 2ee6b10..4e88b18 100644 (file)
--- a/drivers/infiniband/hw/mlx5/cq.c
+++ b/drivers/infiniband/hw/mlx5/cq.c
@@ -590,8 +590,7 @@ static int alloc_cq_buf(struct mlx5_ib_dev *dev, struct mlx5_ib_cq_buf *buf,
 {
        int err;
 
-       err = mlx5_buf_alloc(dev->mdev, nent * cqe_size,
-                            PAGE_SIZE * 2, &buf->buf);
+       err = mlx5_buf_alloc(dev->mdev, nent * cqe_size, &buf->buf);
        if (err)
                return err;
 

diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index d35f62d..426eb88 100644 (file)
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -768,7 +768,7 @@ static int create_kernel_qp(struct mlx5_ib_dev *dev,
        qp->sq.offset = qp->rq.wqe_cnt << qp->rq.wqe_shift;
        qp->buf_size = err + (qp->rq.wqe_cnt << qp->rq.wqe_shift);
 
-       err = mlx5_buf_alloc(dev->mdev, qp->buf_size, PAGE_SIZE * 2, &qp->buf);
+       err = mlx5_buf_alloc(dev->mdev, qp->buf_size, &qp->buf);
        if (err) {
                mlx5_ib_dbg(dev, "err %d\n", err);
                goto err_uuar;

diff --git a/drivers/infiniband/hw/mlx5/srq.c b/drivers/infiniband/hw/mlx5/srq.c
index 02d77a2..4242e1d 100644 (file)
--- a/drivers/infiniband/hw/mlx5/srq.c
+++ b/drivers/infiniband/hw/mlx5/srq.c
@@ -165,7 +165,7 @@ static int create_srq_kernel(struct mlx5_ib_dev *dev, struct mlx5_ib_srq *srq,
                return err;
        }
 
-       if (mlx5_buf_alloc(dev->mdev, buf_size, PAGE_SIZE * 2, &srq->buf)) {
+       if (mlx5_buf_alloc(dev->mdev, buf_size, &srq->buf)) {
                mlx5_ib_dbg(dev, "buf alloc failed\n");
                err = -ENOMEM;
                goto err_db;

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/alloc.c b/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
index ac0f7bf..0715b49 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/alloc.c
@@ -42,95 +42,36 @@
 #include "mlx5_core.h"
 
 /* Handling for queue buffers -- we allocate a bunch of memory and
- * register it in a memory region at HCA virtual address 0.  If the
- * requested size is > max_direct, we split the allocation into
- * multiple pages, so we don't require too much contiguous memory.
+ * register it in a memory region at HCA virtual address 0.
  */
 
-int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, int max_direct,
-                  struct mlx5_buf *buf)
+int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, struct mlx5_buf *buf)
 {
        dma_addr_t t;
 
        buf->size = size;
-       if (size <= max_direct) {
-               buf->nbufs        = 1;
-               buf->npages       = 1;
-               buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
-               buf->direct.buf   = dma_zalloc_coherent(&dev->pdev->dev,
-                                                       size, &t, GFP_KERNEL);
-               if (!buf->direct.buf)
-                       return -ENOMEM;
-
-               buf->direct.map = t;
-
-               while (t & ((1 << buf->page_shift) - 1)) {
-                       --buf->page_shift;
-                       buf->npages *= 2;
-               }
-       } else {
-               int i;
-
-               buf->direct.buf  = NULL;
-               buf->nbufs       = (size + PAGE_SIZE - 1) / PAGE_SIZE;
-               buf->npages      = buf->nbufs;
-               buf->page_shift  = PAGE_SHIFT;
-               buf->page_list   = kcalloc(buf->nbufs, sizeof(*buf->page_list),
-                                          GFP_KERNEL);
-               if (!buf->page_list)
-                       return -ENOMEM;
-
-               for (i = 0; i < buf->nbufs; i++) {
-                       buf->page_list[i].buf =
-                               dma_zalloc_coherent(&dev->pdev->dev, PAGE_SIZE,
-                                                   &t, GFP_KERNEL);
-                       if (!buf->page_list[i].buf)
-                               goto err_free;
-
-                       buf->page_list[i].map = t;
-               }
-
-               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->page_list[i].buf);
-                       buf->direct.buf = vmap(pages, buf->nbufs, VM_MAP, PAGE_KERNEL);
-                       kfree(pages);
-                       if (!buf->direct.buf)
-                               goto err_free;
-               }
-       }
+       buf->npages       = 1;
+       buf->page_shift   = (u8)get_order(size) + PAGE_SHIFT;
+       buf->direct.buf   = dma_zalloc_coherent(&dev->pdev->dev,
+                                               size, &t, GFP_KERNEL);
+       if (!buf->direct.buf)
+               return -ENOMEM;
 
-       return 0;
+       buf->direct.map = t;
 
-err_free:
-       mlx5_buf_free(dev, buf);
+       while (t & ((1 << buf->page_shift) - 1)) {
+               --buf->page_shift;
+               buf->npages *= 2;
+       }
 
-       return -ENOMEM;
+       return 0;
 }
 EXPORT_SYMBOL_GPL(mlx5_buf_alloc);
 
 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf)
 {
-       int i;
-
-       if (buf->nbufs == 1)
-               dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
-                                 buf->direct.map);
-       else {
-               if (BITS_PER_LONG == 64)
-                       vunmap(buf->direct.buf);
-
-               for (i = 0; i < buf->nbufs; i++)
-                       if (buf->page_list[i].buf)
-                               dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
-                                                 buf->page_list[i].buf,
-                                                 buf->page_list[i].map);
-               kfree(buf->page_list);
-       }
+       dma_free_coherent(&dev->pdev->dev, buf->size, buf->direct.buf,
+                         buf->direct.map);
 }
 EXPORT_SYMBOL_GPL(mlx5_buf_free);
 
@@ -230,10 +171,7 @@ void mlx5_fill_page_array(struct mlx5_buf *buf, __be64 *pas)
        int i;
 
        for (i = 0; i < buf->npages; i++) {
-               if (buf->nbufs == 1)
-                       addr = buf->direct.map + (i << buf->page_shift);
-               else
-                       addr = buf->page_list[i].map;
+               addr = buf->direct.map + (i << buf->page_shift);
 
                pas[i] = cpu_to_be64(addr);
        }

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eq.c b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
index 58800e4..3f511bd 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
@@ -346,8 +346,7 @@ int mlx5_create_map_eq(struct mlx5_core_dev *dev, struct mlx5_eq *eq, u8 vecidx,
        int inlen;
 
        eq->nent = roundup_pow_of_two(nent + MLX5_NUM_SPARE_EQE);
-       err = mlx5_buf_alloc(dev, eq->nent * MLX5_EQE_SIZE, 2 * PAGE_SIZE,
-                            &eq->buf);
+       err = mlx5_buf_alloc(dev, eq->nent * MLX5_EQE_SIZE, &eq->buf);
        if (err)
                return err;
 

diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 9a90e75..c4cf25f 100644 (file)
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -334,8 +334,6 @@ struct mlx5_buf_list {
 
 struct mlx5_buf {
        struct mlx5_buf_list    direct;
-       struct mlx5_buf_list   *page_list;
-       int                     nbufs;
        int                     npages;
        int                     size;
        u8                      page_shift;
@@ -586,11 +584,7 @@ struct mlx5_pas {
 
 static inline void *mlx5_buf_offset(struct mlx5_buf *buf, int offset)
 {
-       if (likely(BITS_PER_LONG == 64 || buf->nbufs == 1))
                return buf->direct.buf + offset;
-       else
-               return buf->page_list[offset >> PAGE_SHIFT].buf +
-                       (offset & (PAGE_SIZE - 1));
 }
 
 extern struct workqueue_struct *mlx5_core_wq;
@@ -669,8 +663,7 @@ void mlx5_health_cleanup(void);
 void  __init mlx5_health_init(void);
 void mlx5_start_health_poll(struct mlx5_core_dev *dev);
 void mlx5_stop_health_poll(struct mlx5_core_dev *dev);
-int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, int max_direct,
-                  struct mlx5_buf *buf);
+int mlx5_buf_alloc(struct mlx5_core_dev *dev, int size, struct mlx5_buf *buf);
 void mlx5_buf_free(struct mlx5_core_dev *dev, struct mlx5_buf *buf);
 struct mlx5_cmd_mailbox *mlx5_alloc_cmd_mailbox_chain(struct mlx5_core_dev *dev,
                                                      gfp_t flags, int npages);