qeth: fix page breaks in hw headers

Turning on memory debugging showed there could be page breaks in
hardware headers. OSA does not allow this so we had to add code
to bounce the header in case there is a page break. This patch also
fixes a problem in case the skb->data part of a fragmented skb
spreads multiple pages.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 0b4250d3a25d3ef29fd6636227fecb454f3474f8..d79892782a2b2cf1ef5b9a25eb281d87c6cbff47 100644 (file)
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -869,6 +869,7 @@ void qeth_core_get_drvinfo(struct net_device *, struct ethtool_drvinfo *);
 void qeth_dbf_longtext(debug_info_t *id, int level, char *text, ...);
 int qeth_core_ethtool_get_settings(struct net_device *, struct ethtool_cmd *);
 int qeth_set_access_ctrl_online(struct qeth_card *card);
+int qeth_hdr_chk_and_bounce(struct sk_buff *, int);
 
 /* exports for OSN */
 int qeth_osn_assist(struct net_device *, void *, int);

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 3cdd2705b75ae4b02ce701c734723228da7cd497..656a6e78a2ee2e2a249e9508d7681c969fb40859 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -57,48 +57,6 @@ static void qeth_free_buffer_pool(struct qeth_card *);
 static int qeth_qdio_establish(struct qeth_card *);
 
 
-static inline void __qeth_fill_buffer_frag(struct sk_buff *skb,
-               struct qdio_buffer *buffer, int is_tso,
-               int *next_element_to_fill)
-{
-       struct skb_frag_struct *frag;
-       int fragno;
-       unsigned long addr;
-       int element, cnt, dlen;
-
-       fragno = skb_shinfo(skb)->nr_frags;
-       element = *next_element_to_fill;
-       dlen = 0;
-
-       if (is_tso)
-               buffer->element[element].flags =
-                       SBAL_FLAGS_MIDDLE_FRAG;
-       else
-               buffer->element[element].flags =
-                       SBAL_FLAGS_FIRST_FRAG;
-       dlen = skb->len - skb->data_len;
-       if (dlen) {
-               buffer->element[element].addr = skb->data;
-               buffer->element[element].length = dlen;
-               element++;
-       }
-       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++;
-       }
-       *next_element_to_fill = element;
-}
-
 static inline const char *qeth_get_cardname(struct qeth_card *card)
 {
        if (card->info.guestlan) {
@@ -3020,13 +2978,11 @@ EXPORT_SYMBOL_GPL(qeth_get_priority_queue);
 int qeth_get_elements_no(struct qeth_card *card, void *hdr,
                     struct sk_buff *skb, int elems)
 {
-       int elements_needed = 0;
+       int dlen = skb->len - skb->data_len;
+       int elements_needed = PFN_UP((unsigned long)skb->data + dlen - 1) -
+               PFN_DOWN((unsigned long)skb->data);
 
-       if (skb_shinfo(skb)->nr_frags > 0)
-               elements_needed = (skb_shinfo(skb)->nr_frags + 1);
-       if (elements_needed == 0)
-               elements_needed = 1 + (((((unsigned long) skb->data) %
-                               PAGE_SIZE) + skb->len) >> PAGE_SHIFT);
+       elements_needed += skb_shinfo(skb)->nr_frags;
        if ((elements_needed + elems) > QETH_MAX_BUFFER_ELEMENTS(card)) {
                QETH_DBF_MESSAGE(2, "Invalid size of IP packet "
                        "(Number=%d / Length=%d). Discarded.\n",
@@ -3037,15 +2993,35 @@ int qeth_get_elements_no(struct qeth_card *card, void *hdr,
 }
 EXPORT_SYMBOL_GPL(qeth_get_elements_no);
 
+int qeth_hdr_chk_and_bounce(struct sk_buff *skb, int len)
+{
+       int hroom, inpage, rest;
+
+       if (((unsigned long)skb->data & PAGE_MASK) !=
+           (((unsigned long)skb->data + len - 1) & PAGE_MASK)) {
+               hroom = skb_headroom(skb);
+               inpage = PAGE_SIZE - ((unsigned long) skb->data % PAGE_SIZE);
+               rest = len - inpage;
+               if (rest > hroom)
+                       return 1;
+               memmove(skb->data - rest, skb->data, skb->len - skb->data_len);
+               skb->data -= rest;
+               QETH_DBF_MESSAGE(2, "skb bounce len: %d rest: %d\n", len, rest);
+       }
+       return 0;
+}
+EXPORT_SYMBOL_GPL(qeth_hdr_chk_and_bounce);
+
 static inline void __qeth_fill_buffer(struct sk_buff *skb,
        struct qdio_buffer *buffer, int is_tso, int *next_element_to_fill,
        int offset)
 {
-       int length = skb->len;
+       int length = skb->len - skb->data_len;
        int length_here;
        int element;
        char *data;
-       int first_lap ;
+       int first_lap, cnt;
+       struct skb_frag_struct *frag;
 
        element = *next_element_to_fill;
        data = skb->data;
@@ -3068,10 +3044,14 @@ static inline void __qeth_fill_buffer(struct sk_buff *skb,
                length -= length_here;
                if (!length) {
                        if (first_lap)
-                               buffer->element[element].flags = 0;
+                               if (skb_shinfo(skb)->nr_frags)
+                                       buffer->element[element].flags =
+                                               SBAL_FLAGS_FIRST_FRAG;
+                               else
+                                       buffer->element[element].flags = 0;
                        else
                                buffer->element[element].flags =
-                                   SBAL_FLAGS_LAST_FRAG;
+                                   SBAL_FLAGS_MIDDLE_FRAG;
                } else {
                        if (first_lap)
                                buffer->element[element].flags =
@@ -3084,6 +3064,18 @@ static inline void __qeth_fill_buffer(struct sk_buff *skb,
                element++;
                first_lap = 0;
        }
+
+       for (cnt = 0; cnt < skb_shinfo(skb)->nr_frags; cnt++) {
+               frag = &skb_shinfo(skb)->frags[cnt];
+               buffer->element[element].addr = (char *)page_to_phys(frag->page)
+                       + frag->page_offset;
+               buffer->element[element].length = frag->size;
+               buffer->element[element].flags = SBAL_FLAGS_MIDDLE_FRAG;
+               element++;
+       }
+
+       if (buffer->element[element - 1].flags)
+               buffer->element[element - 1].flags = SBAL_FLAGS_LAST_FRAG;
        *next_element_to_fill = element;
 }
 
@@ -3124,12 +3116,8 @@ static inline int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
                buf->next_element_to_fill++;
        }
 
-       if (skb_shinfo(skb)->nr_frags == 0)
-               __qeth_fill_buffer(skb, buffer, large_send,
-                               (int *)&buf->next_element_to_fill, offset);
-       else
-               __qeth_fill_buffer_frag(skb, buffer, large_send,
-                                       (int *)&buf->next_element_to_fill);
+       __qeth_fill_buffer(skb, buffer, large_send,
+               (int *)&buf->next_element_to_fill, offset);
 
        if (!queue->do_pack) {
                QETH_CARD_TEXT(queue->card, 6, "fillbfnp");

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index e7942ccab98705e550c66ecf33add02952d03480..32d07c2dcc67b6c64e64e44cbff201185591710b 100644 (file)
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -712,10 +712,13 @@ static int qeth_l2_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
                goto tx_drop;
        }
 
-       if (card->info.type != QETH_CARD_TYPE_IQD)
+       if (card->info.type != QETH_CARD_TYPE_IQD) {
+               if (qeth_hdr_chk_and_bounce(new_skb,
+                   sizeof(struct qeth_hdr_layer2)))
+                       goto tx_drop;
                rc = qeth_do_send_packet(card, queue, new_skb, hdr,
                                         elements);
-       else
+       } else
                rc = qeth_do_send_packet_fast(card, queue, new_skb, hdr,
                                        elements, data_offset, hd_len);
        if (!rc) {

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index b5733e405ed95277fc96bd51bf48300be95decab..61d348e51920a584add110bc23f39fee954836b6 100644 (file)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -2904,19 +2904,11 @@ static inline int qeth_l3_tso_elements(struct sk_buff *skb)
        unsigned long tcpd = (unsigned long)tcp_hdr(skb) +
                tcp_hdr(skb)->doff * 4;
        int tcpd_len = skb->len - (tcpd - (unsigned long)skb->data);
-       int elements = PFN_UP(tcpd + tcpd_len) - PFN_DOWN(tcpd);
+       int elements = PFN_UP(tcpd + tcpd_len - 1) - PFN_DOWN(tcpd);
        elements += skb_shinfo(skb)->nr_frags;
        return elements;
 }
 
-static inline int qeth_l3_tso_check(struct sk_buff *skb)
-{
-       int len = ((unsigned long)tcp_hdr(skb) + tcp_hdr(skb)->doff * 4) -
-               (unsigned long)skb->data;
-       return (((unsigned long)skb->data & PAGE_MASK) !=
-               (((unsigned long)skb->data + len) & PAGE_MASK));
-}
-
 static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
        int rc;
@@ -3016,8 +3008,6 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
            (cast_type == RTN_UNSPEC)) {
                hdr = (struct qeth_hdr *)skb_push(new_skb,
                                                sizeof(struct qeth_hdr_tso));
-               if (qeth_l3_tso_check(new_skb))
-                       QETH_DBF_MESSAGE(2, "tso skb misaligned\n");
                memset(hdr, 0, sizeof(struct qeth_hdr_tso));
                qeth_l3_fill_header(card, hdr, new_skb, ipv, cast_type);
                qeth_tso_fill_header(card, hdr, new_skb);
@@ -3048,10 +3038,20 @@ static int qeth_l3_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
        elements_needed += elems;
        nr_frags = skb_shinfo(new_skb)->nr_frags;
 
-       if (card->info.type != QETH_CARD_TYPE_IQD)
+       if (card->info.type != QETH_CARD_TYPE_IQD) {
+               int len;
+               if (large_send == QETH_LARGE_SEND_TSO)
+                       len = ((unsigned long)tcp_hdr(new_skb) +
+                               tcp_hdr(new_skb)->doff * 4) -
+                               (unsigned long)new_skb->data;
+               else
+                       len = sizeof(struct qeth_hdr_layer3);
+
+               if (qeth_hdr_chk_and_bounce(new_skb, len))
+                       goto tx_drop;
                rc = qeth_do_send_packet(card, queue, new_skb, hdr,
                                         elements_needed);
-       else
+       } else
                rc = qeth_do_send_packet_fast(card, queue, new_skb, hdr,
                                        elements_needed, data_offset, 0);