isdn/gigaset: honor CAPI application's buffer size request

Fix the Gigaset CAPI driver to limit the length of a connection's
payload data receive buffers to the corresponding CAPI application's
data buffer size, as some real-life CAPI applications tend to be
rather unhappy if they receive bigger data blocks than requested.

Impact: bugfix
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/isdn/gigaset/asyncdata.c b/drivers/isdn/gigaset/asyncdata.c
index c5016bd..c3b1dc3 100644 (file)
--- a/drivers/isdn/gigaset/asyncdata.c
+++ b/drivers/isdn/gigaset/asyncdata.c
@@ -126,26 +126,6 @@ static unsigned lock_loop(unsigned numbytes, struct inbuf_t *inbuf)
        return numbytes;
 }
 
-/* set up next receive skb for data mode
- */
-static void new_rcv_skb(struct bc_state *bcs)
-{
-       struct cardstate *cs = bcs->cs;
-       unsigned short hw_hdr_len = cs->hw_hdr_len;
-
-       if (bcs->ignore) {
-               bcs->skb = NULL;
-               return;
-       }
-
-       bcs->skb = dev_alloc_skb(SBUFSIZE + hw_hdr_len);
-       if (bcs->skb == NULL) {
-               dev_warn(cs->dev, "could not allocate new skb\n");
-               return;
-       }
-       skb_reserve(bcs->skb, hw_hdr_len);
-}
-
 /* process a block of received bytes in HDLC data mode
  * (mstate != MS_LOCKED && !(inputstate & INS_command) && proto2 == L2_HDLC)
  * Collect HDLC frames, undoing byte stuffing and watching for DLE escapes.
@@ -159,8 +139,8 @@ static unsigned hdlc_loop(unsigned numbytes, struct inbuf_t *inbuf)
        struct cardstate *cs = inbuf->cs;
        struct bc_state *bcs = cs->bcs;
        int inputstate = bcs->inputstate;
-       __u16 fcs = bcs->fcs;
-       struct sk_buff *skb = bcs->skb;
+       __u16 fcs = bcs->rx_fcs;
+       struct sk_buff *skb = bcs->rx_skb;
        unsigned char *src = inbuf->data + inbuf->head;
        unsigned procbytes = 0;
        unsigned char c;
@@ -245,8 +225,7 @@ byte_stuff:
 
                                /* prepare reception of next frame */
                                inputstate &= ~INS_have_data;
-                               new_rcv_skb(bcs);
-                               skb = bcs->skb;
+                               skb = gigaset_new_rx_skb(bcs);
                        } else {
                                /* empty frame (7E 7E) */
 #ifdef CONFIG_GIGASET_DEBUG
@@ -255,8 +234,7 @@ byte_stuff:
                                if (!skb) {
                                        /* skipped (?) */
                                        gigaset_isdn_rcv_err(bcs);
-                                       new_rcv_skb(bcs);
-                                       skb = bcs->skb;
+                                       skb = gigaset_new_rx_skb(bcs);
                                }
                        }
 
@@ -279,11 +257,11 @@ byte_stuff:
 #endif
                inputstate |= INS_have_data;
                if (skb) {
-                       if (skb->len == SBUFSIZE) {
+                       if (skb->len >= bcs->rx_bufsize) {
                                dev_warn(cs->dev, "received packet too long\n");
                                dev_kfree_skb_any(skb);
                                /* skip remainder of packet */
-                               bcs->skb = skb = NULL;
+                               bcs->rx_skb = skb = NULL;
                        } else {
                                *__skb_put(skb, 1) = c;
                                fcs = crc_ccitt_byte(fcs, c);
@@ -292,7 +270,7 @@ byte_stuff:
        }
 
        bcs->inputstate = inputstate;
-       bcs->fcs = fcs;
+       bcs->rx_fcs = fcs;
        return procbytes;
 }
 
@@ -308,18 +286,18 @@ static unsigned iraw_loop(unsigned numbytes, struct inbuf_t *inbuf)
        struct cardstate *cs = inbuf->cs;
        struct bc_state *bcs = cs->bcs;
        int inputstate = bcs->inputstate;
-       struct sk_buff *skb = bcs->skb;
+       struct sk_buff *skb = bcs->rx_skb;
        unsigned char *src = inbuf->data + inbuf->head;
        unsigned procbytes = 0;
        unsigned char c;
 
        if (!skb) {
                /* skip this block */
-               new_rcv_skb(bcs);
+               gigaset_new_rx_skb(bcs);
                return numbytes;
        }
 
-       while (procbytes < numbytes && skb->len < SBUFSIZE) {
+       while (procbytes < numbytes && skb->len < bcs->rx_bufsize) {
                c = *src++;
                procbytes++;
 
@@ -343,7 +321,7 @@ static unsigned iraw_loop(unsigned numbytes, struct inbuf_t *inbuf)
        if (inputstate & INS_have_data) {
                gigaset_skb_rcvd(bcs, skb);
                inputstate &= ~INS_have_data;
-               new_rcv_skb(bcs);
+               gigaset_new_rx_skb(bcs);
        }
 
        bcs->inputstate = inputstate;

diff --git a/drivers/isdn/gigaset/capi.c b/drivers/isdn/gigaset/capi.c
index 8f78f15..245a608 100644 (file)
--- a/drivers/isdn/gigaset/capi.c
+++ b/drivers/isdn/gigaset/capi.c
@@ -80,6 +80,7 @@ struct gigaset_capi_appl {
        struct list_head ctrlist;
        struct gigaset_capi_appl *bcnext;
        u16 id;
+       struct capi_register_params rp;
        u16 nextMessageNumber;
        u32 listenInfoMask;
        u32 listenCIPmask;
@@ -945,6 +946,7 @@ static void gigaset_register_appl(struct capi_ctr *ctr, u16 appl,
                return;
        }
        ap->id = appl;
+       ap->rp = *rp;
 
        list_add(&ap->ctrlist, &iif->appls);
 }
@@ -1166,6 +1168,9 @@ static void do_connect_req(struct gigaset_capi_ctr *iif,
        }
        ap->bcnext = NULL;
        bcs->ap = ap;
+       bcs->rx_bufsize = ap->rp.datablklen;
+       dev_kfree_skb(bcs->rx_skb);
+       gigaset_new_rx_skb(bcs);
        cmsg->adr.adrPLCI |= (bcs->channel + 1) << 8;
 
        /* build command table */
@@ -1435,6 +1440,9 @@ static void do_connect_resp(struct gigaset_capi_ctr *iif,
                                        CapiCallGivenToOtherApplication);
                ap->bcnext = NULL;
                bcs->ap = ap;
+               bcs->rx_bufsize = ap->rp.datablklen;
+               dev_kfree_skb(bcs->rx_skb);
+               gigaset_new_rx_skb(bcs);
                bcs->chstate |= CHS_NOTIFY_LL;
 
                /* check/encode B channel protocol */

diff --git a/drivers/isdn/gigaset/common.c b/drivers/isdn/gigaset/common.c
index f6f45f2..9778fab 100644 (file)
--- a/drivers/isdn/gigaset/common.c
+++ b/drivers/isdn/gigaset/common.c
@@ -399,8 +399,8 @@ static void gigaset_freebcs(struct bc_state *bcs)
        gig_dbg(DEBUG_INIT, "clearing bcs[%d]->at_state", bcs->channel);
        clear_at_state(&bcs->at_state);
        gig_dbg(DEBUG_INIT, "freeing bcs[%d]->skb", bcs->channel);
-       dev_kfree_skb(bcs->skb);
-       bcs->skb = NULL;
+       dev_kfree_skb(bcs->rx_skb);
+       bcs->rx_skb = NULL;
 
        for (i = 0; i < AT_NUM; ++i) {
                kfree(bcs->commands[i]);
@@ -634,19 +634,10 @@ static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
        bcs->emptycount = 0;
 #endif
 
-       gig_dbg(DEBUG_INIT, "allocating bcs[%d]->skb", channel);
-       bcs->fcs = PPP_INITFCS;
+       bcs->rx_bufsize = 0;
+       bcs->rx_skb = NULL;
+       bcs->rx_fcs = PPP_INITFCS;
        bcs->inputstate = 0;
-       if (cs->ignoreframes) {
-               bcs->skb = NULL;
-       } else {
-               bcs->skb = dev_alloc_skb(SBUFSIZE + cs->hw_hdr_len);
-               if (bcs->skb != NULL)
-                       skb_reserve(bcs->skb, cs->hw_hdr_len);
-               else
-                       pr_err("out of memory\n");
-       }
-
        bcs->channel = channel;
        bcs->cs = cs;
 
@@ -663,11 +654,6 @@ static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
                return bcs;
 
        gig_dbg(DEBUG_INIT, "  failed");
-
-       gig_dbg(DEBUG_INIT, "  freeing bcs[%d]->skb", channel);
-       dev_kfree_skb(bcs->skb);
-       bcs->skb = NULL;
-
        return NULL;
 }
 
@@ -839,14 +825,12 @@ void gigaset_bcs_reinit(struct bc_state *bcs)
        bcs->emptycount = 0;
 #endif
 
-       bcs->fcs = PPP_INITFCS;
+       bcs->rx_fcs = PPP_INITFCS;
        bcs->chstate = 0;
 
        bcs->ignore = cs->ignoreframes;
-       if (bcs->ignore) {
-               dev_kfree_skb(bcs->skb);
-               bcs->skb = NULL;
-       }
+       dev_kfree_skb(bcs->rx_skb);
+       bcs->rx_skb = NULL;
 
        cs->ops->reinitbcshw(bcs);
 }

diff --git a/drivers/isdn/gigaset/gigaset.h b/drivers/isdn/gigaset/gigaset.h
index 05947f9..f77ec54 100644 (file)
--- a/drivers/isdn/gigaset/gigaset.h
+++ b/drivers/isdn/gigaset/gigaset.h
@@ -45,10 +45,6 @@
 #define MAX_EVENTS 64          /* size of event queue */
 
 #define RBUFSIZE 8192
-#define SBUFSIZE 4096          /* sk_buff payload size */
-
-#define TRANSBUFSIZE 768       /* bytes per skb for transparent receive */
-#define MAX_BUF_SIZE (SBUFSIZE - 2)    /* Max. size of a data packet from LL */
 
 /* compile time options */
 #define GIG_MAJOR 0
@@ -380,8 +376,10 @@ struct bc_state {
 
        struct at_state_t at_state;
 
-       __u16 fcs;
-       struct sk_buff *skb;
+       /* receive buffer */
+       unsigned rx_bufsize;            /* max size accepted by application */
+       struct sk_buff *rx_skb;
+       __u16 rx_fcs;
        int inputstate;                 /* see INS_XXXX */
 
        int channel;
@@ -801,8 +799,23 @@ static inline void gigaset_bchannel_up(struct bc_state *bcs)
        gigaset_schedule_event(bcs->cs);
 }
 
-/* handling routines for sk_buff */
-/* ============================= */
+/* set up next receive skb for data mode */
+static inline struct sk_buff *gigaset_new_rx_skb(struct bc_state *bcs)
+{
+       struct cardstate *cs = bcs->cs;
+       unsigned short hw_hdr_len = cs->hw_hdr_len;
+
+       if (bcs->ignore) {
+               bcs->rx_skb = NULL;
+       } else {
+               bcs->rx_skb = dev_alloc_skb(bcs->rx_bufsize + hw_hdr_len);
+               if (bcs->rx_skb == NULL)
+                       dev_warn(cs->dev, "could not allocate skb\n");
+               else
+                       skb_reserve(bcs->rx_skb, hw_hdr_len);
+       }
+       return bcs->rx_skb;
+}
 
 /* append received bytes to inbuf */
 int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,

diff --git a/drivers/isdn/gigaset/i4l.c b/drivers/isdn/gigaset/i4l.c
index c22e5ac..f01c3c2 100644 (file)
--- a/drivers/isdn/gigaset/i4l.c
+++ b/drivers/isdn/gigaset/i4l.c
@@ -16,7 +16,10 @@
 #include "gigaset.h"
 #include <linux/isdnif.h>
 
+#define SBUFSIZE       4096    /* sk_buff payload size */
+#define TRANSBUFSIZE   768     /* bytes per skb for transparent receive */
 #define HW_HDR_LEN     2       /* Header size used to store ack info */
+#define MAX_BUF_SIZE   (SBUFSIZE - HW_HDR_LEN) /* max data packet from LL */
 
 /* == Handling of I4L IO =====================================================*/
 
@@ -231,6 +234,15 @@ static int command_from_LL(isdn_ctrl *cntrl)
                        dev_err(cs->dev, "ISDN_CMD_DIAL: channel not free\n");
                        return -EBUSY;
                }
+               switch (bcs->proto2) {
+               case L2_HDLC:
+                       bcs->rx_bufsize = SBUFSIZE;
+                       break;
+               default:                        /* assume transparent */
+                       bcs->rx_bufsize = TRANSBUFSIZE;
+               }
+               dev_kfree_skb(bcs->rx_skb);
+               gigaset_new_rx_skb(bcs);
 
                commands = kzalloc(AT_NUM*(sizeof *commands), GFP_ATOMIC);
                if (!commands) {
@@ -314,6 +326,15 @@ static int command_from_LL(isdn_ctrl *cntrl)
                        return -EINVAL;
                }
                bcs = cs->bcs + ch;
+               switch (bcs->proto2) {
+               case L2_HDLC:
+                       bcs->rx_bufsize = SBUFSIZE;
+                       break;
+               default:                        /* assume transparent */
+                       bcs->rx_bufsize = TRANSBUFSIZE;
+               }
+               dev_kfree_skb(bcs->rx_skb);
+               gigaset_new_rx_skb(bcs);
                if (!gigaset_add_event(cs, &bcs->at_state,
                                       EV_ACCEPT, NULL, 0, NULL))
                        return -ENOMEM;

diff --git a/drivers/isdn/gigaset/isocdata.c b/drivers/isdn/gigaset/isocdata.c
index 16fd3bd..2dfd346 100644 (file)
--- a/drivers/isdn/gigaset/isocdata.c
+++ b/drivers/isdn/gigaset/isocdata.c
@@ -500,19 +500,18 @@ int gigaset_isoc_buildframe(struct bc_state *bcs, unsigned char *in, int len)
  */
 static inline void hdlc_putbyte(unsigned char c, struct bc_state *bcs)
 {
-       bcs->fcs = crc_ccitt_byte(bcs->fcs, c);
-       if (unlikely(bcs->skb == NULL)) {
+       bcs->rx_fcs = crc_ccitt_byte(bcs->rx_fcs, c);
+       if (bcs->rx_skb == NULL)
                /* skipping */
                return;
-       }
-       if (unlikely(bcs->skb->len == SBUFSIZE)) {
+       if (bcs->rx_skb->len >= bcs->rx_bufsize) {
                dev_warn(bcs->cs->dev, "received oversized packet discarded\n");
                bcs->hw.bas->giants++;
-               dev_kfree_skb_any(bcs->skb);
-               bcs->skb = NULL;
+               dev_kfree_skb_any(bcs->rx_skb);
+               bcs->rx_skb = NULL;
                return;
        }
-       *__skb_put(bcs->skb, 1) = c;
+       *__skb_put(bcs->rx_skb, 1) = c;
 }
 
 /* hdlc_flush
@@ -521,18 +520,13 @@ static inline void hdlc_putbyte(unsigned char c, struct bc_state *bcs)
 static inline void hdlc_flush(struct bc_state *bcs)
 {
        /* clear skb or allocate new if not skipping */
-       if (likely(bcs->skb != NULL))
-               skb_trim(bcs->skb, 0);
-       else if (!bcs->ignore) {
-               bcs->skb = dev_alloc_skb(SBUFSIZE + bcs->cs->hw_hdr_len);
-               if (bcs->skb)
-                       skb_reserve(bcs->skb, bcs->cs->hw_hdr_len);
-               else
-                       dev_err(bcs->cs->dev, "could not allocate skb\n");
-       }
+       if (bcs->rx_skb != NULL)
+               skb_trim(bcs->rx_skb, 0);
+       else
+               gigaset_new_rx_skb(bcs);
 
        /* reset packet state */
-       bcs->fcs = PPP_INITFCS;
+       bcs->rx_fcs = PPP_INITFCS;
 }
 
 /* hdlc_done
@@ -549,7 +543,7 @@ static inline void hdlc_done(struct bc_state *bcs)
                hdlc_flush(bcs);
                return;
        }
-       procskb = bcs->skb;
+       procskb = bcs->rx_skb;
        if (procskb == NULL) {
                /* previous error */
                gig_dbg(DEBUG_ISO, "%s: skb=NULL", __func__);
@@ -560,8 +554,8 @@ static inline void hdlc_done(struct bc_state *bcs)
                bcs->hw.bas->runts++;
                dev_kfree_skb_any(procskb);
                gigaset_isdn_rcv_err(bcs);
-       } else if (bcs->fcs != PPP_GOODFCS) {
-               dev_notice(cs->dev, "frame check error (0x%04x)\n", bcs->fcs);
+       } else if (bcs->rx_fcs != PPP_GOODFCS) {
+               dev_notice(cs->dev, "frame check error\n");
                bcs->hw.bas->fcserrs++;
                dev_kfree_skb_any(procskb);
                gigaset_isdn_rcv_err(bcs);
@@ -574,13 +568,8 @@ static inline void hdlc_done(struct bc_state *bcs)
                bcs->hw.bas->goodbytes += len;
                gigaset_skb_rcvd(bcs, procskb);
        }
-
-       bcs->skb = dev_alloc_skb(SBUFSIZE + cs->hw_hdr_len);
-       if (bcs->skb)
-               skb_reserve(bcs->skb, cs->hw_hdr_len);
-       else
-               dev_err(cs->dev, "could not allocate skb\n");
-       bcs->fcs = PPP_INITFCS;
+       gigaset_new_rx_skb(bcs);
+       bcs->rx_fcs = PPP_INITFCS;
 }
 
 /* hdlc_frag
@@ -597,8 +586,8 @@ static inline void hdlc_frag(struct bc_state *bcs, unsigned inbits)
        dev_notice(bcs->cs->dev, "received partial byte (%d bits)\n", inbits);
        bcs->hw.bas->alignerrs++;
        gigaset_isdn_rcv_err(bcs);
-       __skb_trim(bcs->skb, 0);
-       bcs->fcs = PPP_INITFCS;
+       __skb_trim(bcs->rx_skb, 0);
+       bcs->rx_fcs = PPP_INITFCS;
 }
 
 /* bit counts lookup table for HDLC bit unstuffing
@@ -847,7 +836,6 @@ static inline void hdlc_unpack(unsigned char *src, unsigned count,
 static inline void trans_receive(unsigned char *src, unsigned count,
                                 struct bc_state *bcs)
 {
-       struct cardstate *cs = bcs->cs;
        struct sk_buff *skb;
        int dobytes;
        unsigned char *dst;
@@ -857,17 +845,11 @@ static inline void trans_receive(unsigned char *src, unsigned count,
                hdlc_flush(bcs);
                return;
        }
-       skb = bcs->skb;
-       if (unlikely(skb == NULL)) {
-               bcs->skb = skb = dev_alloc_skb(SBUFSIZE + cs->hw_hdr_len);
-               if (!skb) {
-                       dev_err(cs->dev, "could not allocate skb\n");
-                       return;
-               }
-               skb_reserve(skb, cs->hw_hdr_len);
-       }
+       skb = bcs->rx_skb;
+       if (skb == NULL)
+               skb = gigaset_new_rx_skb(bcs);
        bcs->hw.bas->goodbytes += skb->len;
-       dobytes = TRANSBUFSIZE - skb->len;
+       dobytes = bcs->rx_bufsize - skb->len;
        while (count > 0) {
                dst = skb_put(skb, count < dobytes ? count : dobytes);
                while (count > 0 && dobytes > 0) {
@@ -879,14 +861,10 @@ static inline void trans_receive(unsigned char *src, unsigned count,
                        dump_bytes(DEBUG_STREAM_DUMP,
                                   "rcv data", skb->data, skb->len);
                        gigaset_skb_rcvd(bcs, skb);
-                       bcs->skb = skb =
-                               dev_alloc_skb(SBUFSIZE + cs->hw_hdr_len);
-                       if (!skb) {
-                               dev_err(cs->dev, "could not allocate skb\n");
+                       skb = gigaset_new_rx_skb(bcs);
+                       if (skb == NULL)
                                return;
-                       }
-                       skb_reserve(skb, cs->hw_hdr_len);
-                       dobytes = TRANSBUFSIZE;
+                       dobytes = bcs->rx_bufsize;
                }
        }
 }