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Diffstat (limited to 'net/caif/cfrfml.c')
-rw-r--r--net/caif/cfrfml.c314
1 files changed, 260 insertions, 54 deletions
diff --git a/net/caif/cfrfml.c b/net/caif/cfrfml.c
index 689cbfd0e43d..4b04d25b6a3f 100644
--- a/net/caif/cfrfml.c
+++ b/net/caif/cfrfml.c
@@ -7,98 +7,304 @@
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
+#include <linux/unaligned/le_byteshift.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfsrvl.h>
#include <net/caif/cfpkt.h>
-#define container_obj(layr) container_of(layr, struct cfsrvl, layer)
-
+#define container_obj(layr) container_of(layr, struct cfrfml, serv.layer)
#define RFM_SEGMENTATION_BIT 0x01
-#define RFM_PAYLOAD 0x00
-#define RFM_CMD_BIT 0x80
-#define RFM_FLOW_OFF 0x81
-#define RFM_FLOW_ON 0x80
-#define RFM_SET_PIN 0x82
-#define RFM_CTRL_PKT_SIZE 1
+#define RFM_HEAD_SIZE 7
static int cfrfml_receive(struct cflayer *layr, struct cfpkt *pkt);
static int cfrfml_transmit(struct cflayer *layr, struct cfpkt *pkt);
-struct cflayer *cfrfml_create(u8 channel_id, struct dev_info *dev_info)
+struct cfrfml {
+ struct cfsrvl serv;
+ struct cfpkt *incomplete_frm;
+ int fragment_size;
+ u8 seghead[6];
+ u16 pdu_size;
+ /* Protects serialized processing of packets */
+ spinlock_t sync;
+};
+
+static void cfrfml_release(struct kref *kref)
+{
+ struct cfsrvl *srvl = container_of(kref, struct cfsrvl, ref);
+ struct cfrfml *rfml = container_obj(&srvl->layer);
+
+ if (rfml->incomplete_frm)
+ cfpkt_destroy(rfml->incomplete_frm);
+
+ kfree(srvl);
+}
+
+struct cflayer *cfrfml_create(u8 channel_id, struct dev_info *dev_info,
+ int mtu_size)
{
- struct cfsrvl *rfm = kmalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
+ int tmp;
+ struct cfrfml *this =
+ kzalloc(sizeof(struct cfrfml), GFP_ATOMIC);
- if (!rfm) {
+ if (!this) {
pr_warning("CAIF: %s(): Out of memory\n", __func__);
return NULL;
}
- caif_assert(offsetof(struct cfsrvl, layer) == 0);
+ cfsrvl_init(&this->serv, channel_id, dev_info, false);
+ this->serv.release = cfrfml_release;
+ this->serv.layer.receive = cfrfml_receive;
+ this->serv.layer.transmit = cfrfml_transmit;
+
+ /* Round down to closest multiple of 16 */
+ tmp = (mtu_size - RFM_HEAD_SIZE - 6) / 16;
+ tmp *= 16;
+
+ this->fragment_size = tmp;
+ spin_lock_init(&this->sync);
+ snprintf(this->serv.layer.name, CAIF_LAYER_NAME_SZ,
+ "rfm%d", channel_id);
+
+ return &this->serv.layer;
+}
+
+static struct cfpkt *rfm_append(struct cfrfml *rfml, char *seghead,
+ struct cfpkt *pkt, int *err)
+{
+ struct cfpkt *tmppkt;
+ *err = -EPROTO;
+ /* n-th but not last segment */
+
+ if (cfpkt_extr_head(pkt, seghead, 6) < 0)
+ return NULL;
+
+ /* Verify correct header */
+ if (memcmp(seghead, rfml->seghead, 6) != 0)
+ return NULL;
+
+ tmppkt = cfpkt_append(rfml->incomplete_frm, pkt,
+ rfml->pdu_size + RFM_HEAD_SIZE);
+
+ /* If cfpkt_append failes input pkts are not freed */
+ *err = -ENOMEM;
+ if (tmppkt == NULL)
+ return NULL;
- memset(rfm, 0, sizeof(struct cfsrvl));
- cfsrvl_init(rfm, channel_id, dev_info, false);
- rfm->layer.receive = cfrfml_receive;
- rfm->layer.transmit = cfrfml_transmit;
- snprintf(rfm->layer.name, CAIF_LAYER_NAME_SZ, "rfm%d", channel_id);
- return &rfm->layer;
+ *err = 0;
+ return tmppkt;
}
static int cfrfml_receive(struct cflayer *layr, struct cfpkt *pkt)
{
u8 tmp;
bool segmented;
- int ret;
+ int err;
+ u8 seghead[6];
+ struct cfrfml *rfml;
+ struct cfpkt *tmppkt = NULL;
+
caif_assert(layr->up != NULL);
caif_assert(layr->receive != NULL);
+ rfml = container_obj(layr);
+ spin_lock(&rfml->sync);
+
+ err = -EPROTO;
+ if (cfpkt_extr_head(pkt, &tmp, 1) < 0)
+ goto out;
+ segmented = tmp & RFM_SEGMENTATION_BIT;
+
+ if (segmented) {
+ if (rfml->incomplete_frm == NULL) {
+ /* Initial Segment */
+ if (cfpkt_peek_head(pkt, rfml->seghead, 6) < 0)
+ goto out;
+
+ rfml->pdu_size = get_unaligned_le16(rfml->seghead+4);
+
+ if (cfpkt_erroneous(pkt))
+ goto out;
+ rfml->incomplete_frm = pkt;
+ pkt = NULL;
+ } else {
+
+ tmppkt = rfm_append(rfml, seghead, pkt, &err);
+ if (tmppkt == NULL)
+ goto out;
+
+ if (cfpkt_erroneous(tmppkt))
+ goto out;
+
+ rfml->incomplete_frm = tmppkt;
+
+
+ if (cfpkt_erroneous(tmppkt))
+ goto out;
+ }
+ err = 0;
+ goto out;
+ }
+
+ if (rfml->incomplete_frm) {
+
+ /* Last Segment */
+ tmppkt = rfm_append(rfml, seghead, pkt, &err);
+ if (tmppkt == NULL)
+ goto out;
+
+ if (cfpkt_erroneous(tmppkt))
+ goto out;
+
+ rfml->incomplete_frm = NULL;
+ pkt = tmppkt;
+ tmppkt = NULL;
+
+ /* Verify that length is correct */
+ err = EPROTO;
+ if (rfml->pdu_size != cfpkt_getlen(pkt) - RFM_HEAD_SIZE + 1)
+ goto out;
+ }
+
+ err = rfml->serv.layer.up->receive(rfml->serv.layer.up, pkt);
+
+out:
+
+ if (err != 0) {
+ if (tmppkt)
+ cfpkt_destroy(tmppkt);
+ if (pkt)
+ cfpkt_destroy(pkt);
+ if (rfml->incomplete_frm)
+ cfpkt_destroy(rfml->incomplete_frm);
+ rfml->incomplete_frm = NULL;
+
+ pr_info("CAIF: %s(): "
+ "Connection error %d triggered on RFM link\n",
+ __func__, err);
+
+ /* Trigger connection error upon failure.*/
+ layr->up->ctrlcmd(layr->up, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND,
+ rfml->serv.dev_info.id);
+ }
+ spin_unlock(&rfml->sync);
+ return err;
+}
+
+
+static int cfrfml_transmit_segment(struct cfrfml *rfml, struct cfpkt *pkt)
+{
+ caif_assert(!cfpkt_getlen(pkt) < rfml->fragment_size);
+
+ /* Add info for MUX-layer to route the packet out. */
+ cfpkt_info(pkt)->channel_id = rfml->serv.layer.id;
/*
- * RFM is taking care of segmentation and stripping of
- * segmentation bit.
+ * To optimize alignment, we add up the size of CAIF header before
+ * payload.
*/
- if (cfpkt_extr_head(pkt, &tmp, 1) < 0) {
- pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
- cfpkt_destroy(pkt);
- return -EPROTO;
- }
- segmented = tmp & RFM_SEGMENTATION_BIT;
- caif_assert(!segmented);
+ cfpkt_info(pkt)->hdr_len = RFM_HEAD_SIZE;
+ cfpkt_info(pkt)->dev_info = &rfml->serv.dev_info;
- ret = layr->up->receive(layr->up, pkt);
- return ret;
+ return rfml->serv.layer.dn->transmit(rfml->serv.layer.dn, pkt);
}
static int cfrfml_transmit(struct cflayer *layr, struct cfpkt *pkt)
{
- u8 tmp = 0;
- int ret;
- struct cfsrvl *service = container_obj(layr);
+ int err;
+ u8 seg;
+ u8 head[6];
+ struct cfpkt *rearpkt = NULL;
+ struct cfpkt *frontpkt = pkt;
+ struct cfrfml *rfml = container_obj(layr);
caif_assert(layr->dn != NULL);
caif_assert(layr->dn->transmit != NULL);
- if (!cfsrvl_ready(service, &ret))
- return ret;
+ if (!cfsrvl_ready(&rfml->serv, &err))
+ return err;
+
+ err = -EPROTO;
+ if (cfpkt_getlen(pkt) <= RFM_HEAD_SIZE-1)
+ goto out;
+
+ err = 0;
+ if (cfpkt_getlen(pkt) > rfml->fragment_size + RFM_HEAD_SIZE)
+ err = cfpkt_peek_head(pkt, head, 6);
+
+ if (err < 0)
+ goto out;
+
+ while (cfpkt_getlen(frontpkt) > rfml->fragment_size + RFM_HEAD_SIZE) {
+
+ seg = 1;
+ err = -EPROTO;
+
+ if (cfpkt_add_head(frontpkt, &seg, 1) < 0)
+ goto out;
+ /*
+ * On OOM error cfpkt_split returns NULL.
+ *
+ * NOTE: Segmented pdu is not correctly aligned.
+ * This has negative performance impact.
+ */
+
+ rearpkt = cfpkt_split(frontpkt, rfml->fragment_size);
+ if (rearpkt == NULL)
+ goto out;
+
+ err = cfrfml_transmit_segment(rfml, frontpkt);
+
+ if (err != 0)
+ goto out;
+ frontpkt = rearpkt;
+ rearpkt = NULL;
+
+ err = -ENOMEM;
+ if (frontpkt == NULL)
+ goto out;
+ err = -EPROTO;
+ if (cfpkt_add_head(frontpkt, head, 6) < 0)
+ goto out;
- if (cfpkt_getlen(pkt) > CAIF_MAX_PAYLOAD_SIZE) {
- pr_err("CAIF: %s():Packet too large - size=%d\n",
- __func__, cfpkt_getlen(pkt));
- return -EOVERFLOW;
}
- if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
- pr_err("CAIF: %s(): Packet is erroneous!\n", __func__);
- return -EPROTO;
+
+ seg = 0;
+ err = -EPROTO;
+
+ if (cfpkt_add_head(frontpkt, &seg, 1) < 0)
+ goto out;
+
+ err = cfrfml_transmit_segment(rfml, frontpkt);
+
+ frontpkt = NULL;
+out:
+
+ if (err != 0) {
+ pr_info("CAIF: %s(): "
+ "Connection error %d triggered on RFM link\n",
+ __func__, err);
+ /* Trigger connection error upon failure.*/
+
+ layr->up->ctrlcmd(layr->up, CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND,
+ rfml->serv.dev_info.id);
+
+ if (rearpkt)
+ cfpkt_destroy(rearpkt);
+
+ if (frontpkt && frontpkt != pkt) {
+
+ cfpkt_destroy(frontpkt);
+ /*
+ * Socket layer will free the original packet,
+ * but this packet may already be sent and
+ * freed. So we have to return 0 in this case
+ * to avoid socket layer to re-free this packet.
+ * The return of shutdown indication will
+ * cause connection to be invalidated anyhow.
+ */
+ err = 0;
+ }
}
- /* Add info for MUX-layer to route the packet out. */
- cfpkt_info(pkt)->channel_id = service->layer.id;
- /*
- * To optimize alignment, we add up the size of CAIF header before
- * payload.
- */
- cfpkt_info(pkt)->hdr_len = 1;
- cfpkt_info(pkt)->dev_info = &service->dev_info;
- ret = layr->dn->transmit(layr->dn, pkt);
- if (ret < 0)
- cfpkt_extr_head(pkt, &tmp, 1);
- return ret;
+ return err;
}