[net 0/2][pull request] Intel Wired LAN Driver Updates 2016-04-13

[net 0/2][pull request] Intel Wired LAN Driver Updates 2016-04-13

[Jeff Kirsher]

This series contains updates to i40e, i40evf and fm10k.

Alex fixes a bug introduced earlier based on his interpretation of the
XL710 datasheet.  The actual limit for fragments with TSO and a skbuff
that has payload data in the header portion of the buffer is actually
only 7 fragments and the skb-data portion counts as 2 buffers, one for
the TSO header, and the one for a segment payload buffer.

Jacob fixes a bug where in a previous refactor of the code broke
multi-bit updates for VFs.  The problem occurs because a multi-bit
request has a non-zero length, and the PF would simply drop any
request with the upper 16 bits set.

The following are changes since commit a6d37131c02f15463daa00e2f1da6824e8e00de2:
  net: ethernet: renesas: ravb_main: test clock rate to avoid division by 0
and are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-queue master

Alexander Duyck (1):
  i40e/i40evf: Limit TSO to 7 descriptors for payload instead of 8 per
    packet

Jacob Keller (1):
  fm10k: fix multi-bit VLAN update requests from VF

 drivers/net/ethernet/intel/fm10k/fm10k_pf.c   | 30 +++++++++++-----
 drivers/net/ethernet/intel/i40e/i40e_txrx.c   | 49 +++++++++++++--------------
 drivers/net/ethernet/intel/i40e/i40e_txrx.h   | 10 ++++--
 drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 49 +++++++++++++--------------
 drivers/net/ethernet/intel/i40evf/i40e_txrx.h | 10 ++++--
 5 files changed, 84 insertions(+), 64 deletions(-)

-- 
2.5.5

[net 1/2] i40e/i40evf: Limit TSO to 7 descriptors for payload instead of 8 per packet

[Jeff Kirsher]

From: Alexander Duyck <aduyck@mirantis.com>

This patch addresses a bug introduced based on my interpretation of the
XL710 datasheet.  Specifically section 8.4.1 states that "A single transmit
packet may span up to 8 buffers (up to 8 data descriptors per packet
including both the header and payload buffers)."  It then later goes on to
say that each segment for a TSO obeys the previous rule, however it then
refers to TSO header and the segment payload buffers.

I believe the actual limit for fragments with TSO and a skbuff that has
payload data in the header portion of the buffer is actually only 7
fragments as the skb->data portion counts as 2 buffers, one for the TSO
header, and one for a segment payload buffer.

Fixes: 2d37490b82af ("i40e/i40evf: Rewrite logic for 8 descriptor per packet check")
Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_txrx.c   | 49 +++++++++++++--------------
 drivers/net/ethernet/intel/i40e/i40e_txrx.h   | 10 ++++--
 drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 49 +++++++++++++--------------
 drivers/net/ethernet/intel/i40evf/i40e_txrx.h | 10 ++++--
 4 files changed, 62 insertions(+), 56 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 084d0ab..6a49b7a 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2594,35 +2594,34 @@ int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
 }
 
 /**
- * __i40e_chk_linearize - Check if there are more than 8 fragments per packet
+ * __i40e_chk_linearize - Check if there are more than 8 buffers per packet
  * @skb:      send buffer
  *
- * Note: Our HW can't scatter-gather more than 8 fragments to build
- * a packet on the wire and so we need to figure out the cases where we
- * need to linearize the skb.
+ * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
+ * and so we need to figure out the cases where we need to linearize the skb.
+ *
+ * For TSO we need to count the TSO header and segment payload separately.
+ * As such we need to check cases where we have 7 fragments or more as we
+ * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
+ * the segment payload in the first descriptor, and another 7 for the
+ * fragments.
  **/
 bool __i40e_chk_linearize(struct sk_buff *skb)
 {
 	const struct skb_frag_struct *frag, *stale;
-	int gso_size, nr_frags, sum;
-
-	/* check to see if TSO is enabled, if so we may get a repreive */
-	gso_size = skb_shinfo(skb)->gso_size;
-	if (unlikely(!gso_size))
-		return true;
+	int nr_frags, sum;
 
-	/* no need to check if number of frags is less than 8 */
+	/* no need to check if number of frags is less than 7 */
 	nr_frags = skb_shinfo(skb)->nr_frags;
-	if (nr_frags < I40E_MAX_BUFFER_TXD)
+	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
 		return false;
 
 	/* We need to walk through the list and validate that each group
 	 * of 6 fragments totals at least gso_size.  However we don't need
-	 * to perform such validation on the first or last 6 since the first
-	 * 6 cannot inherit any data from a descriptor before them, and the
-	 * last 6 cannot inherit any data from a descriptor after them.
+	 * to perform such validation on the last 6 since the last 6 cannot
+	 * inherit any data from a descriptor after them.
 	 */
-	nr_frags -= I40E_MAX_BUFFER_TXD - 1;
+	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
 	frag = &skb_shinfo(skb)->frags[0];
 
 	/* Initialize size to the negative value of gso_size minus 1.  We
@@ -2631,21 +2630,21 @@ bool __i40e_chk_linearize(struct sk_buff *skb)
 	 * descriptors for a single transmit as the header and previous
 	 * fragment are already consuming 2 descriptors.
 	 */
-	sum = 1 - gso_size;
+	sum = 1 - skb_shinfo(skb)->gso_size;
 
-	/* Add size of frags 1 through 5 to create our initial sum */
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
+	/* Add size of frags 0 through 4 to create our initial sum */
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
 
 	/* Walk through fragments adding latest fragment, testing it, and
 	 * then removing stale fragments from the sum.
 	 */
 	stale = &skb_shinfo(skb)->frags[0];
 	for (;;) {
-		sum += skb_frag_size(++frag);
+		sum += skb_frag_size(frag++);
 
 		/* if sum is negative we failed to make sufficient progress */
 		if (sum < 0)
@@ -2655,7 +2654,7 @@ bool __i40e_chk_linearize(struct sk_buff *skb)
 		if (!--nr_frags)
 			break;
 
-		sum -= skb_frag_size(++stale);
+		sum -= skb_frag_size(stale++);
 	}
 
 	return false;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index cdd5dc0..a9bd705 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -413,10 +413,14 @@ static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
  **/
 static inline bool i40e_chk_linearize(struct sk_buff *skb, int count)
 {
-	/* we can only support up to 8 data buffers for a single send */
-	if (likely(count <= I40E_MAX_BUFFER_TXD))
+	/* Both TSO and single send will work if count is less than 8 */
+	if (likely(count < I40E_MAX_BUFFER_TXD))
 		return false;
 
-	return __i40e_chk_linearize(skb);
+	if (skb_is_gso(skb))
+		return __i40e_chk_linearize(skb);
+
+	/* we can support up to 8 data buffers for a single send */
+	return count != I40E_MAX_BUFFER_TXD;
 }
 #endif /* _I40E_TXRX_H_ */
diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
index ebcc25c..cea97da 100644
--- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
@@ -1796,35 +1796,34 @@ static void i40e_create_tx_ctx(struct i40e_ring *tx_ring,
 }
 
 /**
- * __i40evf_chk_linearize - Check if there are more than 8 fragments per packet
+ * __i40evf_chk_linearize - Check if there are more than 8 buffers per packet
  * @skb:      send buffer
  *
- * Note: Our HW can't scatter-gather more than 8 fragments to build
- * a packet on the wire and so we need to figure out the cases where we
- * need to linearize the skb.
+ * Note: Our HW can't DMA more than 8 buffers to build a packet on the wire
+ * and so we need to figure out the cases where we need to linearize the skb.
+ *
+ * For TSO we need to count the TSO header and segment payload separately.
+ * As such we need to check cases where we have 7 fragments or more as we
+ * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
+ * the segment payload in the first descriptor, and another 7 for the
+ * fragments.
  **/
 bool __i40evf_chk_linearize(struct sk_buff *skb)
 {
 	const struct skb_frag_struct *frag, *stale;
-	int gso_size, nr_frags, sum;
-
-	/* check to see if TSO is enabled, if so we may get a repreive */
-	gso_size = skb_shinfo(skb)->gso_size;
-	if (unlikely(!gso_size))
-		return true;
+	int nr_frags, sum;
 
-	/* no need to check if number of frags is less than 8 */
+	/* no need to check if number of frags is less than 7 */
 	nr_frags = skb_shinfo(skb)->nr_frags;
-	if (nr_frags < I40E_MAX_BUFFER_TXD)
+	if (nr_frags < (I40E_MAX_BUFFER_TXD - 1))
 		return false;
 
 	/* We need to walk through the list and validate that each group
 	 * of 6 fragments totals at least gso_size.  However we don't need
-	 * to perform such validation on the first or last 6 since the first
-	 * 6 cannot inherit any data from a descriptor before them, and the
-	 * last 6 cannot inherit any data from a descriptor after them.
+	 * to perform such validation on the last 6 since the last 6 cannot
+	 * inherit any data from a descriptor after them.
 	 */
-	nr_frags -= I40E_MAX_BUFFER_TXD - 1;
+	nr_frags -= I40E_MAX_BUFFER_TXD - 2;
 	frag = &skb_shinfo(skb)->frags[0];
 
 	/* Initialize size to the negative value of gso_size minus 1.  We
@@ -1833,21 +1832,21 @@ bool __i40evf_chk_linearize(struct sk_buff *skb)
 	 * descriptors for a single transmit as the header and previous
 	 * fragment are already consuming 2 descriptors.
 	 */
-	sum = 1 - gso_size;
+	sum = 1 - skb_shinfo(skb)->gso_size;
 
-	/* Add size of frags 1 through 5 to create our initial sum */
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
-	sum += skb_frag_size(++frag);
+	/* Add size of frags 0 through 4 to create our initial sum */
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
+	sum += skb_frag_size(frag++);
 
 	/* Walk through fragments adding latest fragment, testing it, and
 	 * then removing stale fragments from the sum.
 	 */
 	stale = &skb_shinfo(skb)->frags[0];
 	for (;;) {
-		sum += skb_frag_size(++frag);
+		sum += skb_frag_size(frag++);
 
 		/* if sum is negative we failed to make sufficient progress */
 		if (sum < 0)
@@ -1857,7 +1856,7 @@ bool __i40evf_chk_linearize(struct sk_buff *skb)
 		if (!--nr_frags)
 			break;
 
-		sum -= skb_frag_size(++stale);
+		sum -= skb_frag_size(stale++);
 	}
 
 	return false;
diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.h b/drivers/net/ethernet/intel/i40evf/i40e_txrx.h
index c1dd8c5..0429553 100644
--- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.h
@@ -395,10 +395,14 @@ static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size)
  **/
 static inline bool i40e_chk_linearize(struct sk_buff *skb, int count)
 {
-	/* we can only support up to 8 data buffers for a single send */
-	if (likely(count <= I40E_MAX_BUFFER_TXD))
+	/* Both TSO and single send will work if count is less than 8 */
+	if (likely(count < I40E_MAX_BUFFER_TXD))
 		return false;
 
-	return __i40evf_chk_linearize(skb);
+	if (skb_is_gso(skb))
+		return __i40evf_chk_linearize(skb);
+
+	/* we can support up to 8 data buffers for a single send */
+	return count != I40E_MAX_BUFFER_TXD;
 }
 #endif /* _I40E_TXRX_H_ */
-- 
2.5.5

[net 2/2] fm10k: fix multi-bit VLAN update requests from VF

[Jeff Kirsher]

From: Jacob Keller <jacob.e.keller@intel.com>

The VF uses a multi-bit update request to clear unused VLANs whenever it
resets. However, an accident in a previous refector broke multi-bit
updates for VFs, due to misreading a comment in fm10k_vf.c and
attempting to reduce code duplication. The problem occurs because
a multi-bit request has a non-zero length, and the PF would simply drop
any request with the upper 16 bits set.

We can't simply remove the check of the upper 16 bits and the call to
fm10k_iov_select vid, because this would remove the checks for default
VID and for ensuring no other VLANs can be enabled except pf_vid when it
has been set. To resolve that issue, this revision uses the
iov_select_vid when we have a single-bit update, and denies any
multi-bit update when the VLAN was administratively set by the PF. This
should be ok since the PF properly updates VLAN_TABLE when it assigns
the PF vid. This ensures that requests to add or remove the PF vid work
as expected, but a rogue VF could not use the multi-bit update as
a loophole to attempt receiving traffic on other VLANs.

Reported-by: Ngai-Mint Kwan <ngai-mint.kwan@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/ethernet/intel/fm10k/fm10k_pf.c | 30 +++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pf.c b/drivers/net/ethernet/intel/fm10k/fm10k_pf.c
index 62ccebc..8cf943d 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_pf.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_pf.c
@@ -1223,18 +1223,32 @@ s32 fm10k_iov_msg_mac_vlan_pf(struct fm10k_hw *hw, u32 **results,
 		if (err)
 			return err;
 
-		/* verify upper 16 bits are zero */
-		if (vid >> 16)
-			return FM10K_ERR_PARAM;
-
 		set = !(vid & FM10K_VLAN_CLEAR);
 		vid &= ~FM10K_VLAN_CLEAR;
 
-		err = fm10k_iov_select_vid(vf_info, (u16)vid);
-		if (err < 0)
-			return err;
+		/* if the length field has been set, this is a multi-bit
+		 * update request. For multi-bit requests, simply disallow
+		 * them when the pf_vid has been set. In this case, the PF
+		 * should have already cleared the VLAN_TABLE, and if we
+		 * allowed them, it could allow a rogue VF to receive traffic
+		 * on a VLAN it was not assigned. In the single-bit case, we
+		 * need to modify requests for VLAN 0 to use the default PF or
+		 * SW vid when assigned.
+		 */
 
-		vid = err;
+		if (vid >> 16) {
+			/* prevent multi-bit requests when PF has
+			 * administratively set the VLAN for this VF
+			 */
+			if (vf_info->pf_vid)
+				return FM10K_ERR_PARAM;
+		} else {
+			err = fm10k_iov_select_vid(vf_info, (u16)vid);
+			if (err < 0)
+				return err;
+
+			vid = err;
+		}
 
 		/* update VSI info for VF in regards to VLAN table */
 		err = hw->mac.ops.update_vlan(hw, vid, vf_info->vsi, set);
-- 
2.5.5

Re: [net 0/2][pull request] Intel Wired LAN Driver Updates 2016-04-13

[David Miller]

From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Wed, 13 Apr 2016 20:47:10 -0700

> This series contains updates to i40e, i40evf and fm10k.

Pulled, thanks Jeff.