cxgb4: drop __GFP_NOFAIL allocation

set_filter_wr is requesting __GFP_NOFAIL allocation although it can return
ENOMEM without any problems obviously (t4_l2t_set_switching does that
already).  So the non-failing requirement is too strong without any
obvious reason.  Drop __GFP_NOFAIL and reorganize the code to have the
failure paths easier.

The same applies to _c4iw_write_mem_dma_aligned which uses __GFP_NOFAIL
and then checks the return value and returns -ENOMEM on failure.  This
doesn't make any sense what so ever.  Either the allocation cannot fail or
it can.

del_filter_wr seems to be safe as well because the filter entry is not
marked as pending and the return value is propagated up the stack up to
c4iw_destroy_listen.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 13 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/cxgb4/mem.c b/drivers/infiniband/hw/cxgb4/mem.c
index 6791fd16272c..3ef0cf9f5c44 100644
--- a/drivers/infiniband/hw/cxgb4/mem.c
+++ b/drivers/infiniband/hw/cxgb4/mem.c
@@ -73,7 +73,7 @@ static int _c4iw_write_mem_dma_aligned(struct c4iw_rdev *rdev, u32 addr,
                 c4iw_init_wr_wait(&wr_wait);
         wr_len = roundup(sizeof(*req) + sizeof(*sgl), 16);
 
-        skb = alloc_skb(wr_len, GFP_KERNEL | __GFP_NOFAIL);
+        skb = alloc_skb(wr_len, GFP_KERNEL);
         if (!skb)
                 return -ENOMEM;
         set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index 6de054404156..803d91beec6f 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -1140,6 +1140,10 @@ static int set_filter_wr(struct adapter *adapter, int fidx)
         struct fw_filter_wr *fwr;
         unsigned int ftid;
 
+        skb = alloc_skb(sizeof(*fwr), GFP_KERNEL);
+        if (!skb)
+                return -ENOMEM;
+
         /* If the new filter requires loopback Destination MAC and/or VLAN
          * rewriting then we need to allocate a Layer 2 Table (L2T) entry for
          * the filter.
@@ -1147,19 +1151,21 @@ static int set_filter_wr(struct adapter *adapter, int fidx)
         if (f->fs.newdmac || f->fs.newvlan) {
                 /* allocate L2T entry for new filter */
                 f->l2t = t4_l2t_alloc_switching(adapter->l2t);
-                if (f->l2t == NULL)
+                if (f->l2t == NULL) {
+                        kfree_skb(skb);
                         return -EAGAIN;
+                }
                 if (t4_l2t_set_switching(adapter, f->l2t, f->fs.vlan,
                                         f->fs.eport, f->fs.dmac)) {
                         cxgb4_l2t_release(f->l2t);
                         f->l2t = NULL;
+                        kfree_skb(skb);
                         return -ENOMEM;
                 }
         }
 
         ftid = adapter->tids.ftid_base + fidx;
 
-        skb = alloc_skb(sizeof(*fwr), GFP_KERNEL | __GFP_NOFAIL);
         fwr = (struct fw_filter_wr *)__skb_put(skb, sizeof(*fwr));
         memset(fwr, 0, sizeof(*fwr));
 
@@ -1257,7 +1263,10 @@ static int del_filter_wr(struct adapter *adapter, int fidx)
         len = sizeof(*fwr);
         ftid = adapter->tids.ftid_base + fidx;
 
-        skb = alloc_skb(len, GFP_KERNEL | __GFP_NOFAIL);
+        skb = alloc_skb(len, GFP_KERNEL);
+        if (!skb)
+                return -ENOMEM;
+
         fwr = (struct fw_filter_wr *)__skb_put(skb, len);
         t4_mk_filtdelwr(ftid, fwr, adapter->sge.fw_evtq.abs_id);