mlx4_core: Fix integer overflows so 8TBs of memory registration works

This patch adds on the fixes done in commits 89dd86db78e0 ("mlx4_core:
Allow large mlx4_buddy bitmaps") and 3de819e6b642 ("mlx4_core: Fix
integer overflow issues around MTT table") so that memory registration
of up to 8TB (log_num_mtt=31) finally works.

It fixes integer overflows in a few mlx4_table_yyy routines in icm.c
by using a u64 intermediate variable, and int/uint issues that caused
table indexes to become nagive by setting some variables to be u32
instead of int.  These problems cause crashes when a user attempted to
register > 512GB of RAM.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

2 files changed, 23 insertions, 17 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/icm.c b/drivers/net/ethernet/mellanox/mlx4/icm.c
index daf417923661..31d02649be41 100644
--- a/drivers/net/ethernet/mellanox/mlx4/icm.c
+++ b/drivers/net/ethernet/mellanox/mlx4/icm.c
@@ -227,9 +227,10 @@ int mlx4_UNMAP_ICM_AUX(struct mlx4_dev *dev)
                         MLX4_CMD_TIME_CLASS_B, MLX4_CMD_NATIVE);
 }
 
-int mlx4_table_get(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj)
+int mlx4_table_get(struct mlx4_dev *dev, struct mlx4_icm_table *table, u32 obj)
 {
-        int i = (obj & (table->num_obj - 1)) / (MLX4_TABLE_CHUNK_SIZE / table->obj_size);
+        u32 i = (obj & (table->num_obj - 1)) /
+                        (MLX4_TABLE_CHUNK_SIZE / table->obj_size);
         int ret = 0;
 
         mutex_lock(&table->mutex);
@@ -262,16 +263,18 @@ out:
         return ret;
 }
 
-void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj)
+void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, u32 obj)
 {
-        int i;
+        u32 i;
+        u64 offset;
 
         i = (obj & (table->num_obj - 1)) / (MLX4_TABLE_CHUNK_SIZE / table->obj_size);
 
         mutex_lock(&table->mutex);
 
         if (--table->icm[i]->refcount == 0) {
-                mlx4_UNMAP_ICM(dev, table->virt + i * MLX4_TABLE_CHUNK_SIZE,
+                offset = (u64) i * MLX4_TABLE_CHUNK_SIZE;
+                mlx4_UNMAP_ICM(dev, table->virt + offset,
                                MLX4_TABLE_CHUNK_SIZE / MLX4_ICM_PAGE_SIZE);
                 mlx4_free_icm(dev, table->icm[i], table->coherent);
                 table->icm[i] = NULL;
@@ -280,9 +283,11 @@ void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj)
         mutex_unlock(&table->mutex);
 }
 
-void *mlx4_table_find(struct mlx4_icm_table *table, int obj, dma_addr_t *dma_handle)
+void *mlx4_table_find(struct mlx4_icm_table *table, u32 obj,
+                        dma_addr_t *dma_handle)
 {
-        int idx, offset, dma_offset, i;
+        int offset, dma_offset, i;
+        u64 idx;
         struct mlx4_icm_chunk *chunk;
         struct mlx4_icm *icm;
         struct page *page = NULL;
@@ -292,7 +297,7 @@ void *mlx4_table_find(struct mlx4_icm_table *table, int obj, dma_addr_t *dma_han
 
         mutex_lock(&table->mutex);
 
-        idx = (obj & (table->num_obj - 1)) * table->obj_size;
+        idx = (u64) (obj & (table->num_obj - 1)) * table->obj_size;
         icm = table->icm[idx / MLX4_TABLE_CHUNK_SIZE];
         dma_offset = offset = idx % MLX4_TABLE_CHUNK_SIZE;
 
@@ -326,10 +331,11 @@ out:
 }
 
 int mlx4_table_get_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
-                         int start, int end)
+                         u32 start, u32 end)
 {
         int inc = MLX4_TABLE_CHUNK_SIZE / table->obj_size;
-        int i, err;
+        int err;
+        u32 i;
 
         for (i = start; i <= end; i += inc) {
                 err = mlx4_table_get(dev, table, i);
@@ -349,9 +355,9 @@ fail:
 }
 
 void mlx4_table_put_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
-                          int start, int end)
+                          u32 start, u32 end)
 {
-        int i;
+        u32 i;
 
         for (i = start; i <= end; i += MLX4_TABLE_CHUNK_SIZE / table->obj_size)
                 mlx4_table_put(dev, table, i);
diff --git a/drivers/net/ethernet/mellanox/mlx4/icm.h b/drivers/net/ethernet/mellanox/mlx4/icm.h
index a67744f53506..dee67fa39107 100644
--- a/drivers/net/ethernet/mellanox/mlx4/icm.h
+++ b/drivers/net/ethernet/mellanox/mlx4/icm.h
@@ -71,17 +71,17 @@ struct mlx4_icm *mlx4_alloc_icm(struct mlx4_dev *dev, int npages,
                                 gfp_t gfp_mask, int coherent);
 void mlx4_free_icm(struct mlx4_dev *dev, struct mlx4_icm *icm, int coherent);
 
-int mlx4_table_get(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj);
-void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, int obj);
+int mlx4_table_get(struct mlx4_dev *dev, struct mlx4_icm_table *table, u32 obj);
+void mlx4_table_put(struct mlx4_dev *dev, struct mlx4_icm_table *table, u32 obj);
 int mlx4_table_get_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
-                         int start, int end);
+                         u32 start, u32 end);
 void mlx4_table_put_range(struct mlx4_dev *dev, struct mlx4_icm_table *table,
-                          int start, int end);
+                          u32 start, u32 end);
 int mlx4_init_icm_table(struct mlx4_dev *dev, struct mlx4_icm_table *table,
                         u64 virt, int obj_size, u32 nobj, int reserved,
                         int use_lowmem, int use_coherent);
 void mlx4_cleanup_icm_table(struct mlx4_dev *dev, struct mlx4_icm_table *table);
-void *mlx4_table_find(struct mlx4_icm_table *table, int obj, dma_addr_t *dma_handle);
+void *mlx4_table_find(struct mlx4_icm_table *table, u32 obj, dma_addr_t *dma_handle);
 
 static inline void mlx4_icm_first(struct mlx4_icm *icm,
                                   struct mlx4_icm_iter *iter)