[PATCH] s390: qeth bug fixes

[patch 7/10] s390: qeth bug fixes.

From: Frank Pavlic <pavlic@de.ibm.com>

qeth network driver changes:
 - Removed redundant code, use the same qeth_fill_buffer_frag
   for TSO path either
 - Using skb->frags solely is not correct since skb->data still
   points to the beginning of the whole data, even when it is
   a small portion we have to fill the qdio buffer with it.

Signed-off-by: Frank Pavlic <pavlic@de.ibm.com>

5 files changed, 86 insertions, 111 deletions

diff --git a/drivers/s390/net/qeth.h b/drivers/s390/net/qeth.h
index a341041a6cf7..501b87e6875a 100644
--- a/drivers/s390/net/qeth.h
+++ b/drivers/s390/net/qeth.h
@@ -24,7 +24,7 @@
 
 #include "qeth_mpc.h"
 
-#define VERSION_QETH_H          "$Revision: 1.135 $"
+#define VERSION_QETH_H          "$Revision: 1.136 $"
 
 #ifdef CONFIG_QETH_IPV6
 #define QETH_VERSION_IPV6       ":IPv6"
@@ -866,6 +866,17 @@ qeth_push_skb(struct qeth_card *card, struct sk_buff **skb, int size)
         return hdr;
 }
 
+static inline int
+qeth_get_skb_data_len(struct sk_buff *skb)
+{
+        int len = skb->len;
+        int i;
+
+        for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i)
+                len -= skb_shinfo(skb)->frags[i].size;
+        return len;
+}
+
 inline static int
 qeth_get_hlen(__u8 link_type)
 {
diff --git a/drivers/s390/net/qeth_eddp.c b/drivers/s390/net/qeth_eddp.c
index 7ee1c06ed68a..45aa4a962daf 100644
--- a/drivers/s390/net/qeth_eddp.c
+++ b/drivers/s390/net/qeth_eddp.c
@@ -1,6 +1,6 @@
 /*
  *
- * linux/drivers/s390/net/qeth_eddp.c ($Revision: 1.11 $)
+ * linux/drivers/s390/net/qeth_eddp.c ($Revision: 1.12 $)
  *
  * Enhanced Device Driver Packing (EDDP) support for the qeth driver.
  *
@@ -8,7 +8,7 @@
  *
  *    Author(s): Thomas Spatzier <tspat@de.ibm.com>
  *
- *    $Revision: 1.11 $  $Date: 2005/03/24 09:04:18 $
+ *    $Revision: 1.12 $  $Date: 2005/04/01 21:40:40 $
  *
  */
 #include <linux/config.h>
@@ -202,17 +202,6 @@ out:
         return flush_cnt;
 }
 
-static inline int
-qeth_get_skb_data_len(struct sk_buff *skb)
-{
-        int len = skb->len;
-        int i;
-
-        for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i)
-                len -= skb_shinfo(skb)->frags[i].size;
-        return len;
-}
-
 static inline void
 qeth_eddp_create_segment_hdrs(struct qeth_eddp_context *ctx,
                               struct qeth_eddp_data *eddp)
diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index 607b92542df6..17e8d16fa06c 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -1,6 +1,6 @@
 /*
  *
- * linux/drivers/s390/net/qeth_main.c ($Revision: 1.206 $)
+ * linux/drivers/s390/net/qeth_main.c ($Revision: 1.207 $)
  *
  * Linux on zSeries OSA Express and HiperSockets support
  *
@@ -12,7 +12,7 @@
  *                        Frank Pavlic (pavlic@de.ibm.com) and
  *                        Thomas Spatzier <tspat@de.ibm.com>
  *
- *    $Revision: 1.206 $         $Date: 2005/03/24 09:04:18 $
+ *    $Revision: 1.207 $         $Date: 2005/04/01 21:40:40 $
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -80,7 +80,7 @@ qeth_eyecatcher(void)
 #include "qeth_eddp.h"
 #include "qeth_tso.h"
 
-#define VERSION_QETH_C "$Revision: 1.206 $"
+#define VERSION_QETH_C "$Revision: 1.207 $"
 static const char *version = "qeth S/390 OSA-Express driver";
 
 /**
@@ -3894,47 +3894,6 @@ qeth_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 }
 
 static inline void
-__qeth_fill_buffer_frag(struct sk_buff *skb, struct qdio_buffer *buffer,
-                        int *next_element_to_fill)
-{
-        int length = skb->len;
-        struct skb_frag_struct *frag;
-        int fragno;
-        unsigned long addr;
-        int element;
-        int first_lap = 1;
-
-        fragno = skb_shinfo(skb)->nr_frags; /* start with last frag */
-        element = *next_element_to_fill + fragno;
-        while (length > 0) {
-                if (fragno > 0) {
-                        frag = &skb_shinfo(skb)->frags[fragno - 1];
-                        addr = (page_to_pfn(frag->page) << PAGE_SHIFT) +
-                                frag->page_offset;
-                        buffer->element[element].addr = (char *)addr;
-                        buffer->element[element].length = frag->size;
-                        length -= frag->size;
-                        if (first_lap)
-                                buffer->element[element].flags =
-                                    SBAL_FLAGS_LAST_FRAG;
-                        else
-                                buffer->element[element].flags =
-                                    SBAL_FLAGS_MIDDLE_FRAG;
-                } else {
-                        buffer->element[element].addr = skb->data;
-                        buffer->element[element].length = length;
-                        length = 0;
-                        buffer->element[element].flags =
-                                SBAL_FLAGS_FIRST_FRAG;
-                }
-                element--;
-                fragno--;
-                first_lap = 0;
-        }
-        *next_element_to_fill += skb_shinfo(skb)->nr_frags + 1;
-}
-
-static inline void
 __qeth_fill_buffer(struct sk_buff *skb, struct qdio_buffer *buffer,
                    int *next_element_to_fill)
 {
@@ -3991,7 +3950,7 @@ qeth_fill_buffer(struct qeth_qdio_out_q *queue,
                 __qeth_fill_buffer(skb, buffer,
                                    (int *)&buf->next_element_to_fill);
         else
-                __qeth_fill_buffer_frag(skb, buffer,
+                __qeth_fill_buffer_frag(skb, buffer, 0,
                                         (int *)&buf->next_element_to_fill);
 
         if (!queue->do_pack) {
diff --git a/drivers/s390/net/qeth_tso.c b/drivers/s390/net/qeth_tso.c
index c91976274e7b..4e58f19cb71c 100644
--- a/drivers/s390/net/qeth_tso.c
+++ b/drivers/s390/net/qeth_tso.c
@@ -1,5 +1,5 @@
 /*
- * linux/drivers/s390/net/qeth_tso.c ($Revision: 1.6 $)
+ * linux/drivers/s390/net/qeth_tso.c ($Revision: 1.7 $)
  *
  * Header file for qeth TCP Segmentation Offload support.
  *
@@ -7,7 +7,7 @@
  *
  *    Author(s): Frank Pavlic <pavlic@de.ibm.com>
  *
- *    $Revision: 1.6 $   $Date: 2005/03/24 09:04:18 $
+ *    $Revision: 1.7 $   $Date: 2005/04/01 21:40:41 $
  *
  */
 
@@ -144,38 +144,6 @@ qeth_tso_get_queue_buffer(struct qeth_qdio_out_q *queue)
         return flush_cnt;
 }
 
-static inline void
-__qeth_tso_fill_buffer_frag(struct qeth_qdio_out_buffer *buf,
-                          struct sk_buff *skb)
-{
-        struct skb_frag_struct *frag;
-        struct qdio_buffer *buffer;
-        int fragno, cnt, element;
-        unsigned long addr;
-
-        QETH_DBF_TEXT(trace, 6, "tsfilfrg");
-
-        /*initialize variables ...*/
-        fragno = skb_shinfo(skb)->nr_frags;
-        buffer = buf->buffer;
-        element = buf->next_element_to_fill;
-        /*fill buffer elements .....*/
-        for (cnt = 0; cnt < fragno; cnt++) {
-                frag = &skb_shinfo(skb)->frags[cnt];
-                addr = (page_to_pfn(frag->page) << PAGE_SHIFT) +
-                        frag->page_offset;
-                buffer->element[element].addr = (char *)addr;
-                buffer->element[element].length = frag->size;
-                if (cnt < (fragno - 1))
-                        buffer->element[element].flags =
-                                SBAL_FLAGS_MIDDLE_FRAG;
-                else
-                        buffer->element[element].flags =
-                                SBAL_FLAGS_LAST_FRAG;
-                element++;
-        }
-        buf->next_element_to_fill = element;
-}
 
 static inline int
 qeth_tso_fill_buffer(struct qeth_qdio_out_buffer *buf,
@@ -205,19 +173,22 @@ qeth_tso_fill_buffer(struct qeth_qdio_out_buffer *buf,
         buffer->element[element].length = hdr_len;
         buffer->element[element].flags = SBAL_FLAGS_FIRST_FRAG;
         buf->next_element_to_fill++;
-
+        /*check if we have frags ...*/
         if (skb_shinfo(skb)->nr_frags > 0) {
-                 __qeth_tso_fill_buffer_frag(buf, skb);
+                skb->len = length;
+                skb->data = data;
+                 __qeth_fill_buffer_frag(skb, buffer,1,
+                                        (int *)&buf->next_element_to_fill);
                  goto out;
         }
 
-       /*start filling buffer entries ...*/
+       /*... if not, use this */
         element++;
         while (length > 0) {
                 /* length_here is the remaining amount of data in this page */
                 length_here = PAGE_SIZE - ((unsigned long) data % PAGE_SIZE);
                 if (length < length_here)
-                        length_here = length;
+                        length_here = length;
                 buffer->element[element].addr = data;
                 buffer->element[element].length = length_here;
                 length -= length_here;
@@ -230,9 +201,9 @@ qeth_tso_fill_buffer(struct qeth_qdio_out_buffer *buf,
                 data += length_here;
                 element++;
         }
-        /*set the buffer to primed  ...*/
         buf->next_element_to_fill = element;
 out:
+        /*prime buffer now  ...*/
         atomic_set(&buf->state, QETH_QDIO_BUF_PRIMED);
         return 1;
 }
diff --git a/drivers/s390/net/qeth_tso.h b/drivers/s390/net/qeth_tso.h
index 83504dee3f57..ff585ae49b6c 100644
--- a/drivers/s390/net/qeth_tso.h
+++ b/drivers/s390/net/qeth_tso.h
@@ -1,5 +1,5 @@
 /*
- * linux/drivers/s390/net/qeth_tso.h ($Revision: 1.4 $)
+ * linux/drivers/s390/net/qeth_tso.h ($Revision: 1.5 $)
  *
  * Header file for qeth TCP Segmentation Offload support.
  *
@@ -7,7 +7,7 @@
  *
  *    Author(s): Frank Pavlic <pavlic@de.ibm.com>
  *
- *    $Revision: 1.4 $   $Date: 2005/03/24 09:04:18 $
+ *    $Revision: 1.5 $   $Date: 2005/04/01 21:40:41 $
  *
  */
 #ifndef __QETH_TSO_H__
@@ -37,22 +37,67 @@ struct qeth_hdr_tso {
 } __attribute__ ((packed));
 
 /*some helper functions*/
-
 static inline int
 qeth_get_elements_no(struct qeth_card *card, void *hdr, struct sk_buff *skb)
 {
         int elements_needed = 0;
 
-        if (skb_shinfo(skb)->nr_frags > 0)
-                elements_needed = (skb_shinfo(skb)->nr_frags + 1);
-        if (elements_needed == 0 )
-                elements_needed = 1 + (((((unsigned long) hdr) % PAGE_SIZE)
-                                        + skb->len) >> PAGE_SHIFT);
-        if (elements_needed > QETH_MAX_BUFFER_ELEMENTS(card)){
-                PRINT_ERR("qeth_do_send_packet: invalid size of "
-                          "IP packet. Discarded.");
-                return 0;
+        if (skb_shinfo(skb)->nr_frags > 0)
+                elements_needed = (skb_shinfo(skb)->nr_frags + 1);
+        if (elements_needed == 0 )
+                elements_needed = 1 + (((((unsigned long) hdr) % PAGE_SIZE)
+                                        + skb->len) >> PAGE_SHIFT);
+        if (elements_needed > QETH_MAX_BUFFER_ELEMENTS(card)){
+                PRINT_ERR("qeth_do_send_packet: invalid size of "
+                          "IP packet. Discarded.");
+                return 0;
+        }
+        return elements_needed;
+}
+
+static inline void
+__qeth_fill_buffer_frag(struct sk_buff *skb, struct qdio_buffer *buffer,
+                        int is_tso, int *next_element_to_fill)
+{
+        int length = skb->len;
+        struct skb_frag_struct *frag;
+        int fragno;
+        unsigned long addr;
+        int element;
+        int first_lap = 1;
+
+        fragno = skb_shinfo(skb)->nr_frags; /* start with last frag */
+        element = *next_element_to_fill + fragno;
+        while (length > 0) {
+                if (fragno > 0) {
+                        frag = &skb_shinfo(skb)->frags[fragno - 1];
+                        addr = (page_to_pfn(frag->page) << PAGE_SHIFT) +
+                                frag->page_offset;
+                        buffer->element[element].addr = (char *)addr;
+                        buffer->element[element].length = frag->size;
+                        length -= frag->size;
+                        if (first_lap)
+                                buffer->element[element].flags =
+                                    SBAL_FLAGS_LAST_FRAG;
+                        else
+                                buffer->element[element].flags =
+                                    SBAL_FLAGS_MIDDLE_FRAG;
+                } else {
+                        buffer->element[element].addr = skb->data;
+                        buffer->element[element].length = length;
+                        length = 0;
+                        if (is_tso)
+                                buffer->element[element].flags =
+                                        SBAL_FLAGS_MIDDLE_FRAG;
+                        else
+                                buffer->element[element].flags =
+                                        SBAL_FLAGS_FIRST_FRAG;
+                }
+                element--;
+                fragno--;
+                first_lap = 0;
         }
-        return elements_needed;
+        *next_element_to_fill += skb_shinfo(skb)->nr_frags + 1;
 }
+
 #endif /* __QETH_TSO_H__ */