ethtool: Add direct access to ops->get_sset_count

This patch is an alternative approach for accessing string
counts, vs. the drvinfo indirect approach.  This way the drvinfo
space doesn't run out, and we don't break ABI later.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index cca1c3d..f6f961f 100644 (file)
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -253,6 +253,17 @@ struct ethtool_gstrings {
        __u8    data[0];
 };
 
+struct ethtool_sset_info {
+       __u32   cmd;            /* ETHTOOL_GSSET_INFO */
+       __u32   reserved;
+       __u64   sset_mask;      /* input: each bit selects an sset to query */
+                               /* output: each bit a returned sset */
+       __u32   data[0];        /* ETH_SS_xxx count, in order, based on bits
+                                  in sset_mask.  One bit implies one
+                                  __u32, two bits implies two
+                                  __u32's, etc. */
+};
+
 enum ethtool_test_flags {
        ETH_TEST_FL_OFFLINE     = (1 << 0),     /* online / offline */
        ETH_TEST_FL_FAILED      = (1 << 1),     /* test passed / failed */
@@ -606,9 +617,9 @@ struct ethtool_ops {
 #define        ETHTOOL_SRXCLSRLINS     0x00000032 /* Insert RX classification rule */
 #define        ETHTOOL_FLASHDEV        0x00000033 /* Flash firmware to device */
 #define        ETHTOOL_RESET           0x00000034 /* Reset hardware */
-
-#define ETHTOOL_SRXNTUPLE      0x00000035 /* Add an n-tuple filter to device */
-#define ETHTOOL_GRXNTUPLE      0x00000036 /* Get n-tuple filters from device */
+#define        ETHTOOL_SRXNTUPLE       0x00000035 /* Add an n-tuple filter to device */
+#define        ETHTOOL_GRXNTUPLE       0x00000036 /* Get n-tuple filters from device */
+#define        ETHTOOL_GSSET_INFO      0x00000037 /* Get string set info */
 
 /* compatibility with older code */
 #define SPARC_ETH_GSET         ETHTOOL_GSET

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 0f2f821..70075c4 100644 (file)
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -214,6 +214,10 @@ static noinline int ethtool_get_drvinfo(struct net_device *dev, void __user *use
        info.cmd = ETHTOOL_GDRVINFO;
        ops->get_drvinfo(dev, &info);
 
+       /*
+        * this method of obtaining string set info is deprecated;
+        * consider using ETHTOOL_GSSET_INFO instead
+        */
        if (ops->get_sset_count) {
                int rc;
 
@@ -237,6 +241,71 @@ static noinline int ethtool_get_drvinfo(struct net_device *dev, void __user *use
        return 0;
 }
 
+/*
+ * noinline attribute so that gcc doesnt use too much stack in dev_ethtool()
+ */
+static noinline int ethtool_get_sset_info(struct net_device *dev,
+                                          void __user *useraddr)
+{
+       struct ethtool_sset_info info;
+       const struct ethtool_ops *ops = dev->ethtool_ops;
+       u64 sset_mask;
+       int i, idx = 0, n_bits = 0, ret, rc;
+       u32 *info_buf = NULL;
+
+       if (!ops->get_sset_count)
+               return -EOPNOTSUPP;
+
+       if (copy_from_user(&info, useraddr, sizeof(info)))
+               return -EFAULT;
+
+       /* store copy of mask, because we zero struct later on */
+       sset_mask = info.sset_mask;
+       if (!sset_mask)
+               return 0;
+
+       /* calculate size of return buffer */
+       for (i = 0; i < 64; i++)
+               if (sset_mask & (1ULL << i))
+                       n_bits++;
+
+       memset(&info, 0, sizeof(info));
+       info.cmd = ETHTOOL_GSSET_INFO;
+
+       info_buf = kzalloc(n_bits * sizeof(u32), GFP_USER);
+       if (!info_buf)
+               return -ENOMEM;
+
+       /*
+        * fill return buffer based on input bitmask and successful
+        * get_sset_count return
+        */
+       for (i = 0; i < 64; i++) {
+               if (!(sset_mask & (1ULL << i)))
+                       continue;
+
+               rc = ops->get_sset_count(dev, i);
+               if (rc >= 0) {
+                       info.sset_mask |= (1ULL << i);
+                       info_buf[idx++] = rc;
+               }
+       }
+
+       ret = -EFAULT;
+       if (copy_to_user(useraddr, &info, sizeof(info)))
+               goto out;
+
+       useraddr += offsetof(struct ethtool_sset_info, data);
+       if (copy_to_user(useraddr, info_buf, idx * sizeof(u32)))
+               goto out;
+
+       ret = 0;
+
+out:
+       kfree(info_buf);
+       return ret;
+}
+
 /*
  * noinline attribute so that gcc doesnt use too much stack in dev_ethtool()
  */
@@ -1471,6 +1540,9 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
        case ETHTOOL_GRXNTUPLE:
                rc = ethtool_get_rx_ntuple(dev, useraddr);
                break;
+       case ETHTOOL_GSSET_INFO:
+               rc = ethtool_get_sset_info(dev, useraddr);
+               break;
        default:
                rc = -EOPNOTSUPP;
        }