brcm80211: smac: use sk_buff list for handling frames in receive path

In the receive path the frames are obtained from the dma using
multiple sk_buff that were linked using the skb next pointer.
This has been changed and it now used sk_buff lists and skb_queue
functions instead.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Alwin Beukers <alwin@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/brcm80211/brcmsmac/dma.c b/drivers/net/wireless/brcm80211/brcmsmac/dma.c
index 08960ce..ae541fb 100644 (file)
--- a/drivers/net/wireless/brcm80211/brcmsmac/dma.c
+++ b/drivers/net/wireless/brcm80211/brcmsmac/dma.c
@@ -14,7 +14,6 @@
  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 #include <linux/slab.h>
-#include <linux/skbuff.h>
 #include <linux/delay.h>
 #include <linux/pci.h>
 
@@ -901,7 +900,7 @@ static struct sk_buff *_dma_getnextrxp(struct dma_info *di, bool forceall)
 
 /*
  * !! rx entry routine
- * returns a pointer to the next frame received, or NULL if there are no more
+ * returns the number packages in the next frame, or 0 if there are no more
  *   if DMA_CTRL_RXMULTI is defined, DMA scattering(multiple buffers) is
  *   supported with pkts chain
  *   otherwise, it's treated as giant pkt and will be tossed.
@@ -909,38 +908,40 @@ static struct sk_buff *_dma_getnextrxp(struct dma_info *di, bool forceall)
  *   buffer data. After it reaches the max size of buffer, the data continues
  *   in next DMA descriptor buffer WITHOUT DMA header
  */
-struct sk_buff *dma_rx(struct dma_pub *pub)
+int dma_rx(struct dma_pub *pub, struct sk_buff_head *skb_list)
 {
        struct dma_info *di = (struct dma_info *)pub;
-       struct sk_buff *p, *head, *tail;
+       struct sk_buff_head dma_frames;
+       struct sk_buff *p, *next;
        uint len;
        uint pkt_len;
        int resid = 0;
+       int pktcnt = 1;
 
+       skb_queue_head_init(&dma_frames);
  next_frame:
-       head = _dma_getnextrxp(di, false);
-       if (head == NULL)
-               return NULL;
+       p = _dma_getnextrxp(di, false);
+       if (p == NULL)
+               return 0;
 
-       len = le16_to_cpu(*(__le16 *) (head->data));
+       len = le16_to_cpu(*(__le16 *) (p->data));
        DMA_TRACE(("%s: dma_rx len %d\n", di->name, len));
-       dma_spin_for_len(len, head);
+       dma_spin_for_len(len, p);
 
        /* set actual length */
        pkt_len = min((di->rxoffset + len), di->rxbufsize);
-       __skb_trim(head, pkt_len);
+       __skb_trim(p, pkt_len);
+       skb_queue_tail(&dma_frames, p);
        resid = len - (di->rxbufsize - di->rxoffset);
 
        /* check for single or multi-buffer rx */
        if (resid > 0) {
-               tail = head;
                while ((resid > 0) && (p = _dma_getnextrxp(di, false))) {
-                       tail->next = p;
                        pkt_len = min_t(uint, resid, di->rxbufsize);
                        __skb_trim(p, pkt_len);
-
-                       tail = p;
+                       skb_queue_tail(&dma_frames, p);
                        resid -= di->rxbufsize;
+                       pktcnt++;
                }
 
 #ifdef BCMDBG
@@ -959,13 +960,18 @@ struct sk_buff *dma_rx(struct dma_pub *pub)
                if ((di->dma.dmactrlflags & DMA_CTRL_RXMULTI) == 0) {
                        DMA_ERROR(("%s: dma_rx: bad frame length (%d)\n",
                                   di->name, len));
-                       brcmu_pkt_buf_free_skb(head);
+                       skb_queue_walk_safe(&dma_frames, p, next) {
+                               skb_unlink(p, &dma_frames);
+                               brcmu_pkt_buf_free_skb(p);
+                       }
                        di->dma.rxgiants++;
+                       pktcnt = 1;
                        goto next_frame;
                }
        }
 
-       return head;
+       skb_queue_splice_tail(&dma_frames, skb_list);
+       return pktcnt;
 }
 
 static bool dma64_rxidle(struct dma_info *di)

diff --git a/drivers/net/wireless/brcm80211/brcmsmac/dma.h b/drivers/net/wireless/brcm80211/brcmsmac/dma.h
index ebc5bc5..d317c7c 100644 (file)
--- a/drivers/net/wireless/brcm80211/brcmsmac/dma.h
+++ b/drivers/net/wireless/brcm80211/brcmsmac/dma.h
@@ -18,6 +18,7 @@
 #define        _BRCM_DMA_H_
 
 #include <linux/delay.h>
+#include <linux/skbuff.h>
 #include "types.h"             /* forward structure declarations */
 
 /* map/unmap direction */
@@ -80,7 +81,7 @@ extern struct dma_pub *dma_attach(char *name, struct si_pub *sih,
                            uint nrxpost, uint rxoffset, uint *msg_level);
 
 void dma_rxinit(struct dma_pub *pub);
-struct sk_buff *dma_rx(struct dma_pub *pub);
+int dma_rx(struct dma_pub *pub, struct sk_buff_head *skb_list);
 bool dma_rxfill(struct dma_pub *pub);
 bool dma_rxreset(struct dma_pub *pub);
 bool dma_txreset(struct dma_pub *pub);

diff --git a/drivers/net/wireless/brcm80211/brcmsmac/main.c b/drivers/net/wireless/brcm80211/brcmsmac/main.c
index 3f8a6c7..f193fab 100644 (file)
--- a/drivers/net/wireless/brcm80211/brcmsmac/main.c
+++ b/drivers/net/wireless/brcm80211/brcmsmac/main.c
@@ -8115,21 +8115,17 @@ static bool
 brcms_b_recv(struct brcms_hardware *wlc_hw, uint fifo, bool bound)
 {
        struct sk_buff *p;
-       struct sk_buff *head = NULL;
-       struct sk_buff *tail = NULL;
+       struct sk_buff *next = NULL;
+       struct sk_buff_head recv_frames;
+
        uint n = 0;
        uint bound_limit = bound ? RXBND : -1;
 
        BCMMSG(wlc_hw->wlc->wiphy, "wl%d\n", wlc_hw->unit);
-       /* gather received frames */
-       while ((p = dma_rx(wlc_hw->di[fifo]))) {
+       skb_queue_head_init(&recv_frames);
 
-               if (!tail)
-                       head = tail = p;
-               else {
-                       tail->prev = p;
-                       tail = p;
-               }
+       /* gather received frames */
+       while (dma_rx(wlc_hw->di[fifo], &recv_frames)) {
 
                /* !give others some time to run! */
                if (++n >= bound_limit)
@@ -8140,12 +8136,11 @@ brcms_b_recv(struct brcms_hardware *wlc_hw, uint fifo, bool bound)
        dma_rxfill(wlc_hw->di[fifo]);
 
        /* process each frame */
-       while ((p = head) != NULL) {
+       skb_queue_walk_safe(&recv_frames, p, next) {
                struct d11rxhdr_le *rxh_le;
                struct d11rxhdr *rxh;
-               head = head->prev;
-               p->prev = NULL;
 
+               skb_unlink(p, &recv_frames);
                rxh_le = (struct d11rxhdr_le *)p->data;
                rxh = (struct d11rxhdr *)p->data;