IB/mlx5: Decrease memory consumption of mr caches

Change the logic so we do not allocate memory nor map the device
before actually posting to the REG_UMR QP. In addition, unmap and free
the memory after we get completion.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/mlx5/mr.c b/drivers/infiniband/hw/mlx5/mr.c
index e86dbbdb38369f445b10768cc62230415f5773ee..06e33e6cb07fa4855598dabb4bd76a273301cd6c 100644 (file)
--- a/drivers/infiniband/hw/mlx5/mr.c
+++ b/drivers/infiniband/hw/mlx5/mr.c
@@ -61,13 +61,11 @@ static int order2idx(struct mlx5_ib_dev *dev, int order)
 
 static int add_keys(struct mlx5_ib_dev *dev, int c, int num)
 {
-       struct device *ddev = dev->ib_dev.dma_device;
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent = &cache->ent[c];
        struct mlx5_create_mkey_mbox_in *in;
        struct mlx5_ib_mr *mr;
        int npages = 1 << ent->order;
-       int size = sizeof(u64) * npages;
        int err = 0;
        int i;
 
@@ -83,21 +81,6 @@ static int add_keys(struct mlx5_ib_dev *dev, int c, int num)
                }
                mr->order = ent->order;
                mr->umred = 1;
-               mr->pas = kmalloc(size + 0x3f, GFP_KERNEL);
-               if (!mr->pas) {
-                       kfree(mr);
-                       err = -ENOMEM;
-                       goto out;
-               }
-               mr->dma = dma_map_single(ddev, mr_align(mr->pas, 0x40), size,
-                                        DMA_TO_DEVICE);
-               if (dma_mapping_error(ddev, mr->dma)) {
-                       kfree(mr->pas);
-                       kfree(mr);
-                       err = -ENOMEM;
-                       goto out;
-               }
-
                in->seg.status = 1 << 6;
                in->seg.xlt_oct_size = cpu_to_be32((npages + 1) / 2);
                in->seg.qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
@@ -108,8 +91,6 @@ static int add_keys(struct mlx5_ib_dev *dev, int c, int num)
                                            sizeof(*in));
                if (err) {
                        mlx5_ib_warn(dev, "create mkey failed %d\n", err);
-                       dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
-                       kfree(mr->pas);
                        kfree(mr);
                        goto out;
                }
@@ -129,11 +110,9 @@ out:
 
 static void remove_keys(struct mlx5_ib_dev *dev, int c, int num)
 {
-       struct device *ddev = dev->ib_dev.dma_device;
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent = &cache->ent[c];
        struct mlx5_ib_mr *mr;
-       int size;
        int err;
        int i;
 
@@ -149,14 +128,10 @@ static void remove_keys(struct mlx5_ib_dev *dev, int c, int num)
                ent->size--;
                spin_unlock(&ent->lock);
                err = mlx5_core_destroy_mkey(&dev->mdev, &mr->mmr);
-               if (err) {
+               if (err)
                        mlx5_ib_warn(dev, "failed destroy mkey\n");
-               } else {
-                       size = ALIGN(sizeof(u64) * (1 << mr->order), 0x40);
-                       dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
-                       kfree(mr->pas);
+               else
                        kfree(mr);
-               }
        }
 }
 
@@ -408,11 +383,9 @@ static void free_cached_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
 
 static void clean_keys(struct mlx5_ib_dev *dev, int c)
 {
-       struct device *ddev = dev->ib_dev.dma_device;
        struct mlx5_mr_cache *cache = &dev->cache;
        struct mlx5_cache_ent *ent = &cache->ent[c];
        struct mlx5_ib_mr *mr;
-       int size;
        int err;
 
        cancel_delayed_work(&ent->dwork);
@@ -428,14 +401,10 @@ static void clean_keys(struct mlx5_ib_dev *dev, int c)
                ent->size--;
                spin_unlock(&ent->lock);
                err = mlx5_core_destroy_mkey(&dev->mdev, &mr->mmr);
-               if (err) {
+               if (err)
                        mlx5_ib_warn(dev, "failed destroy mkey\n");
-               } else {
-                       size = ALIGN(sizeof(u64) * (1 << mr->order), 0x40);
-                       dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
-                       kfree(mr->pas);
+               else
                        kfree(mr);
-               }
        }
 }
 
@@ -678,10 +647,12 @@ static struct mlx5_ib_mr *reg_umr(struct ib_pd *pd, struct ib_umem *umem,
                                  int page_shift, int order, int access_flags)
 {
        struct mlx5_ib_dev *dev = to_mdev(pd->device);
+       struct device *ddev = dev->ib_dev.dma_device;
        struct umr_common *umrc = &dev->umrc;
        struct ib_send_wr wr, *bad;
        struct mlx5_ib_mr *mr;
        struct ib_sge sg;
+       int size = sizeof(u64) * npages;
        int err;
        int i;
 
@@ -700,6 +671,19 @@ static struct mlx5_ib_mr *reg_umr(struct ib_pd *pd, struct ib_umem *umem,
        if (!mr)
                return ERR_PTR(-EAGAIN);
 
+       mr->pas = kmalloc(size + 0x3f, GFP_KERNEL);
+       if (!mr->pas) {
+               err = -ENOMEM;
+               goto error;
+       }
+       mr->dma = dma_map_single(ddev, mr_align(mr->pas, 0x40), size,
+                                DMA_TO_DEVICE);
+       if (dma_mapping_error(ddev, mr->dma)) {
+               kfree(mr->pas);
+               err = -ENOMEM;
+               goto error;
+       }
+
        mlx5_ib_populate_pas(dev, umem, page_shift, mr_align(mr->pas, 0x40), 1);
 
        memset(&wr, 0, sizeof(wr));
@@ -721,6 +705,9 @@ static struct mlx5_ib_mr *reg_umr(struct ib_pd *pd, struct ib_umem *umem,
        wait_for_completion(&mr->done);
        up(&umrc->sem);
 
+       dma_unmap_single(ddev, mr->dma, size, DMA_TO_DEVICE);
+       kfree(mr->pas);
+
        if (mr->status != IB_WC_SUCCESS) {
                mlx5_ib_warn(dev, "reg umr failed\n");
                err = -EFAULT;