ixgbe: Error handler for duplicate filter locations in hardware for cls_u32 offloads

For u32 classifier filters, avoid overwriting existing filter
in a hardware location without removing it first, to clean up
inconsistencies due to duplicate values for filter location.

Verified with the following filters:

Create child hash tables:
	handle 1: u32 divisor 1
	handle 2: u32 divisor 1

Link to the child hash table from parent hash table:
	handle 800:0:11 u32 ht 800: link 1: \
	offset at 0 mask 0f00 shift 6 plus 0 eat \
	match ip protocol 6 ff match ip dst 15.0.0.1/32

	handle 800:0:12 u32 ht 800: link 2: \
	offset at 0 mask 0f00 shift 6 plus 0 eat \
	match ip protocol 17 ff match ip dst 16.0.0.1/32

Add filter into child hash table:
	handle 1:0:3 u32 ht 1: \
	match tcp src 22 ffff action drop

Add another filter to the same location:
	handle 2:0:3 u32 ht 2: \
	match tcp src 33 ffff action drop

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 75e6855e2c1354c0c452571ede2e38426b576c9f..fd5a761c68f3ce8001acdbfa36b0c29abca7ccf4 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -8315,8 +8315,11 @@ static int ixgbe_delete_clsu32(struct ixgbe_adapter *adapter,
        /* Clear this filter in the link data it is associated with */
        if (uhtid != 0x800) {
                jump = adapter->jump_tables[uhtid];
-               if (jump)
-                       clear_bit(loc - 1, jump->child_loc_map);
+               if (!jump)
+                       return -EINVAL;
+               if (!test_bit(loc - 1, jump->child_loc_map))
+                       return -EINVAL;
+               clear_bit(loc - 1, jump->child_loc_map);
        }
 
        /* Check if the filter being deleted is a link */
@@ -8606,7 +8609,7 @@ static int ixgbe_configure_clsu32(struct ixgbe_adapter *adapter,
                        mask = kzalloc(sizeof(*mask), GFP_KERNEL);
                        if (!mask) {
                                err = -ENOMEM;
-                               goto err_out;
+                               goto free_input;
                        }
                        jump->input = input;
                        jump->mask = mask;
@@ -8629,7 +8632,7 @@ static int ixgbe_configure_clsu32(struct ixgbe_adapter *adapter,
        mask = kzalloc(sizeof(*mask), GFP_KERNEL);
        if (!mask) {
                err = -ENOMEM;
-               goto err_out;
+               goto free_input;
        }
 
        if ((uhtid != 0x800) && (adapter->jump_tables[uhtid])) {
@@ -8639,6 +8642,20 @@ static int ixgbe_configure_clsu32(struct ixgbe_adapter *adapter,
                if ((adapter->jump_tables[uhtid])->mask)
                        memcpy(mask, (adapter->jump_tables[uhtid])->mask,
                               sizeof(*mask));
+
+               /* Lookup in all child hash tables if this location is already
+                * filled with a filter
+                */
+               for (i = 1; i < IXGBE_MAX_LINK_HANDLE; i++) {
+                       struct ixgbe_jump_table *link = adapter->jump_tables[i];
+
+                       if (link && (test_bit(loc - 1, link->child_loc_map))) {
+                               e_err(drv, "Filter exists in location: %x\n",
+                                     loc);
+                               err = -EINVAL;
+                               goto err_out;
+                       }
+               }
        }
        err = ixgbe_clsu32_build_input(input, mask, cls, field_ptr, NULL);
        if (err)
@@ -8670,25 +8687,17 @@ static int ixgbe_configure_clsu32(struct ixgbe_adapter *adapter,
                ixgbe_update_ethtool_fdir_entry(adapter, input, input->sw_idx);
        spin_unlock(&adapter->fdir_perfect_lock);
 
-       if ((uhtid != 0x800) && (adapter->jump_tables[uhtid])) {
-               struct ixgbe_jump_table *link = adapter->jump_tables[uhtid];
+       if ((uhtid != 0x800) && (adapter->jump_tables[uhtid]))
+               set_bit(loc - 1, (adapter->jump_tables[uhtid])->child_loc_map);
 
-               if (test_bit(loc - 1, link->child_loc_map)) {
-                       e_err(drv, "Filter: %x exists in hash table: %x\n",
-                             loc, uhtid);
-                       err = -EINVAL;
-                       goto free_mask;
-               }
-               set_bit(loc - 1, link->child_loc_map);
-       }
        kfree(mask);
        return err;
 err_out_w_lock:
        spin_unlock(&adapter->fdir_perfect_lock);
 err_out:
-       kfree(input);
-free_mask:
        kfree(mask);
+free_input:
+       kfree(input);
 free_jump:
        kfree(jump);
        return err;