[PATCH] USBATM: handle urbs containing partial cells
The receive logic has always assumed that urbs contain an integral
number of ATM cells, which is a bit naughty, though it never caused
any problems with bulk transfers. Isochronous urbs spank us soundly
for this. Fixed thanks to this patch, mostly by Stanislaw Gruszka.
Signed-off-by: Duncan Sands <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>
---
commit e3fb2f641f421662ebda48763f2f03cb9bd29e82
tree 2511087a08a177c27bf28207f3ab05ac3093b85d
parent 80aae7a17afd21f7ba900dd566fb23a2444021f8
author Duncan Sands <[EMAIL PROTECTED]> Fri, 13 Jan 2006 11:06:46 +0100
committer Greg Kroah-Hartman <[EMAIL PROTECTED]> Tue, 31 Jan 2006 17:23:40 -0800
drivers/usb/atm/usbatm.c | 275 ++++++++++++++++++++++++++++++----------------
drivers/usb/atm/usbatm.h | 7 +
2 files changed, 184 insertions(+), 98 deletions(-)
diff --git a/drivers/usb/atm/usbatm.c b/drivers/usb/atm/usbatm.c
index 923f2d9..341430f 100644
--- a/drivers/usb/atm/usbatm.c
+++ b/drivers/usb/atm/usbatm.c
@@ -296,126 +296,159 @@ static inline struct usbatm_vcc_data *us
return NULL;
}
-static void usbatm_extract_cells(struct usbatm_data *instance,
- unsigned char *source, unsigned int avail_data)
+static void usbatm_extract_one_cell(struct usbatm_data *instance, unsigned
char *source)
{
- struct usbatm_vcc_data *cached_vcc = NULL;
struct atm_vcc *vcc;
struct sk_buff *sarb;
- unsigned int stride = instance->rx_channel.stride;
- int vci, cached_vci = 0;
- short vpi, cached_vpi = 0;
- u8 pti;
+ short vpi = ((source[0] & 0x0f) << 4) | (source[1] >> 4);
+ int vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) | (source[3] >>
4);
+ u8 pti = ((source[3] & 0xe) >> 1);
- for (; avail_data >= stride; avail_data -= stride, source += stride) {
- vpi = ((source[0] & 0x0f) << 4) | (source[1] >> 4);
- vci = ((source[1] & 0x0f) << 12) | (source[2] << 4) |
(source[3] >> 4);
- pti = ((source[3] & 0xe) >> 1);
+ vdbg("%s: vpi %hd, vci %d, pti %d", __func__, vpi, vci, pti);
- vdbg("%s: vpi %hd, vci %d, pti %d", __func__, vpi, vci, pti);
+ if ((vci != instance->cached_vci) || (vpi != instance->cached_vpi)) {
+ instance->cached_vpi = vpi;
+ instance->cached_vci = vci;
- if ((vci != cached_vci) || (vpi != cached_vpi)) {
- cached_vpi = vpi;
- cached_vci = vci;
+ instance->cached_vcc = usbatm_find_vcc(instance, vpi, vci);
- cached_vcc = usbatm_find_vcc(instance, vpi, vci);
+ if (!instance->cached_vcc)
+ atm_rldbg(instance, "%s: unknown vpi/vci (%hd/%d)!\n",
__func__, vpi, vci);
+ }
- if (!cached_vcc)
- atm_rldbg(instance, "%s: unknown vpi/vci
(%hd/%d)!\n", __func__, vpi, vci);
- }
+ if (!instance->cached_vcc)
+ return;
- if (!cached_vcc)
- continue;
+ vcc = instance->cached_vcc->vcc;
- vcc = cached_vcc->vcc;
+ /* OAM F5 end-to-end */
+ if (pti == ATM_PTI_E2EF5) {
+ if (printk_ratelimit())
+ atm_warn(instance, "%s: OAM not supported (vpi %d, vci
%d)!\n",
+ __func__, vpi, vci);
+ atomic_inc(&vcc->stats->rx_err);
+ return;
+ }
- /* OAM F5 end-to-end */
- if (pti == ATM_PTI_E2EF5) {
- if (printk_ratelimit())
- atm_warn(instance, "%s: OAM not supported (vpi
%d, vci %d)!\n",
- __func__, vpi, vci);
+ sarb = instance->cached_vcc->sarb;
+
+ if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) {
+ atm_rldbg(instance, "%s: buffer overrun (sarb->len %u, vcc:
0x%p)!\n",
+ __func__, sarb->len, vcc);
+ /* discard cells already received */
+ skb_trim(sarb, 0);
+ UDSL_ASSERT(sarb->tail + ATM_CELL_PAYLOAD <= sarb->end);
+ }
+
+ memcpy(sarb->tail, source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD);
+ __skb_put(sarb, ATM_CELL_PAYLOAD);
+
+ if (pti & 1) {
+ struct sk_buff *skb;
+ unsigned int length;
+ unsigned int pdu_length;
+
+ length = (source[ATM_CELL_SIZE - 6] << 8) +
source[ATM_CELL_SIZE - 5];
+
+ /* guard against overflow */
+ if (length > ATM_MAX_AAL5_PDU) {
+ atm_rldbg(instance, "%s: bogus length %u (vcc:
0x%p)!\n",
+ __func__, length, vcc);
atomic_inc(&vcc->stats->rx_err);
- continue;
+ goto out;
}
- sarb = cached_vcc->sarb;
+ pdu_length = usbatm_pdu_length(length);
- if (sarb->tail + ATM_CELL_PAYLOAD > sarb->end) {
- atm_rldbg(instance, "%s: buffer overrun (sarb->len %u,
vcc: 0x%p)!\n",
- __func__, sarb->len, vcc);
- /* discard cells already received */
- skb_trim(sarb, 0);
- UDSL_ASSERT(sarb->tail + ATM_CELL_PAYLOAD <= sarb->end);
- }
-
- memcpy(sarb->tail, source + ATM_CELL_HEADER, ATM_CELL_PAYLOAD);
- __skb_put(sarb, ATM_CELL_PAYLOAD);
-
- if (pti & 1) {
- struct sk_buff *skb;
- unsigned int length;
- unsigned int pdu_length;
-
- length = (source[ATM_CELL_SIZE - 6] << 8) +
source[ATM_CELL_SIZE - 5];
-
- /* guard against overflow */
- if (length > ATM_MAX_AAL5_PDU) {
- atm_rldbg(instance, "%s: bogus length %u (vcc:
0x%p)!\n",
- __func__, length, vcc);
- atomic_inc(&vcc->stats->rx_err);
- goto out;
- }
+ if (sarb->len < pdu_length) {
+ atm_rldbg(instance, "%s: bogus pdu_length %u
(sarb->len: %u, vcc: 0x%p)!\n",
+ __func__, pdu_length, sarb->len, vcc);
+ atomic_inc(&vcc->stats->rx_err);
+ goto out;
+ }
- pdu_length = usbatm_pdu_length(length);
+ if (crc32_be(~0, sarb->tail - pdu_length, pdu_length) !=
0xc704dd7b) {
+ atm_rldbg(instance, "%s: packet failed crc check (vcc:
0x%p)!\n",
+ __func__, vcc);
+ atomic_inc(&vcc->stats->rx_err);
+ goto out;
+ }
- if (sarb->len < pdu_length) {
- atm_rldbg(instance, "%s: bogus pdu_length %u
(sarb->len: %u, vcc: 0x%p)!\n",
- __func__, pdu_length,
sarb->len, vcc);
- atomic_inc(&vcc->stats->rx_err);
- goto out;
- }
+ vdbg("%s: got packet (length: %u, pdu_length: %u, vcc: 0x%p)",
__func__, length, pdu_length, vcc);
- if (crc32_be(~0, sarb->tail - pdu_length, pdu_length)
!= 0xc704dd7b) {
- atm_rldbg(instance, "%s: packet failed crc
check (vcc: 0x%p)!\n",
- __func__, vcc);
- atomic_inc(&vcc->stats->rx_err);
- goto out;
- }
+ if (!(skb = dev_alloc_skb(length))) {
+ if (printk_ratelimit())
+ atm_err(instance, "%s: no memory for skb
(length: %u)!\n",
+ __func__, length);
+ atomic_inc(&vcc->stats->rx_drop);
+ goto out;
+ }
- vdbg("%s: got packet (length: %u, pdu_length: %u, vcc:
0x%p)", __func__, length, pdu_length, vcc);
+ vdbg("%s: allocated new sk_buff (skb: 0x%p, skb->truesize:
%u)", __func__, skb, skb->truesize);
- if (!(skb = dev_alloc_skb(length))) {
- if (printk_ratelimit())
- atm_err(instance, "%s: no memory for
skb (length: %u)!\n",
- __func__, length);
- atomic_inc(&vcc->stats->rx_drop);
- goto out;
- }
+ if (!atm_charge(vcc, skb->truesize)) {
+ atm_rldbg(instance, "%s: failed atm_charge
(skb->truesize: %u)!\n",
+ __func__, skb->truesize);
+ dev_kfree_skb_any(skb);
+ goto out; /* atm_charge increments rx_drop */
+ }
- vdbg("%s: allocated new sk_buff (skb: 0x%p,
skb->truesize: %u)", __func__, skb, skb->truesize);
+ memcpy(skb->data, sarb->tail - pdu_length, length);
+ __skb_put(skb, length);
- if (!atm_charge(vcc, skb->truesize)) {
- atm_rldbg(instance, "%s: failed atm_charge
(skb->truesize: %u)!\n",
- __func__, skb->truesize);
- dev_kfree_skb_any(skb);
- goto out; /* atm_charge increments
rx_drop */
- }
+ vdbg("%s: sending skb 0x%p, skb->len %u, skb->truesize %u",
+ __func__, skb, skb->len, skb->truesize);
- memcpy(skb->data, sarb->tail - pdu_length, length);
- __skb_put(skb, length);
+ PACKETDEBUG(skb->data, skb->len);
- vdbg("%s: sending skb 0x%p, skb->len %u, skb->truesize
%u",
- __func__, skb, skb->len, skb->truesize);
+ vcc->push(vcc, skb);
- PACKETDEBUG(skb->data, skb->len);
+ atomic_inc(&vcc->stats->rx);
+ out:
+ skb_trim(sarb, 0);
+ }
+}
- vcc->push(vcc, skb);
+static void usbatm_extract_cells(struct usbatm_data *instance,
+ unsigned char *source, unsigned int avail_data)
+{
+ unsigned int stride = instance->rx_channel.stride;
+ unsigned int buf_usage = instance->buf_usage;
- atomic_inc(&vcc->stats->rx);
- out:
- skb_trim(sarb, 0);
+ /* extract cells from incoming data, taking into account that
+ * the length of avail data may not be a multiple of stride */
+
+ if (buf_usage > 0) {
+ /* we have a partially received atm cell */
+ unsigned char *cell_buf = instance->cell_buf;
+ unsigned int space_left = stride - buf_usage;
+
+ UDSL_ASSERT(buf_usage <= stride);
+
+ if (avail_data >= space_left) {
+ /* add new data and process cell */
+ memcpy(cell_buf + buf_usage, source, space_left);
+ source += space_left;
+ avail_data -= space_left;
+ usbatm_extract_one_cell(instance, cell_buf);
+ instance->buf_usage = 0;
+ } else {
+ /* not enough data to fill the cell */
+ memcpy(cell_buf + buf_usage, source, avail_data);
+ instance->buf_usage = buf_usage + avail_data;
+ return;
}
}
+
+ for (; avail_data >= stride; avail_data -= stride, source += stride)
+ usbatm_extract_one_cell(instance, source);
+
+ if (avail_data > 0) {
+ /* length was not a multiple of stride -
+ * save remaining data for next call */
+ memcpy(instance->cell_buf, source, avail_data);
+ instance->buf_usage = avail_data;
+ }
}
@@ -496,16 +529,40 @@ static void usbatm_rx_process(unsigned l
vdbg("%s: processing urb 0x%p", __func__, urb);
if (usb_pipeisoc(urb->pipe)) {
+ unsigned char *merge_start = NULL;
+ unsigned int merge_length = 0;
+ const unsigned int packet_size =
instance->rx_channel.packet_size;
int i;
- for (i = 0; i < urb->number_of_packets; i++)
- if (!urb->iso_frame_desc[i].status)
- usbatm_extract_cells(instance,
- (u8
*)urb->transfer_buffer + urb->iso_frame_desc[i].offset,
-
urb->iso_frame_desc[i].actual_length);
- }
- else
+
+ for (i = 0; i < urb->number_of_packets; i++) {
+ if (!urb->iso_frame_desc[i].status) {
+ unsigned int actual_length =
urb->iso_frame_desc[i].actual_length;
+
+ UDSL_ASSERT(actual_length <=
packet_size);
+
+ if (!merge_length)
+ merge_start = (unsigned char
*)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
+ merge_length += actual_length;
+ if (merge_length && (actual_length <
packet_size)) {
+ usbatm_extract_cells(instance,
merge_start, merge_length);
+ merge_length = 0;
+ }
+ } else {
+ atm_rldbg(instance, "%s: status %d in
frame %d!\n", __func__, urb->status, i);
+ if (merge_length)
+ usbatm_extract_cells(instance,
merge_start, merge_length);
+ merge_length = 0;
+ instance->buf_usage = 0;
+ }
+ }
+
+ if (merge_length)
+ usbatm_extract_cells(instance, merge_start,
merge_length);
+ } else
if (!urb->status)
usbatm_extract_cells(instance,
urb->transfer_buffer, urb->actual_length);
+ else
+ instance->buf_usage = 0;
if (usbatm_submit_urb(urb))
return;
@@ -797,6 +854,9 @@ static int usbatm_atm_open(struct atm_vc
vcc->dev_data = new;
tasklet_disable(&instance->rx_channel.tasklet);
+ instance->cached_vcc = new;
+ instance->cached_vpi = vpi;
+ instance->cached_vci = vci;
list_add(&new->list, &instance->vcc_list);
tasklet_enable(&instance->rx_channel.tasklet);
@@ -836,6 +896,11 @@ static void usbatm_atm_close(struct atm_
down(&instance->serialize); /* vs self, usbatm_atm_open,
usbatm_usb_disconnect */
tasklet_disable(&instance->rx_channel.tasklet);
+ if (instance->cached_vcc == vcc_data) {
+ instance->cached_vcc = NULL;
+ instance->cached_vpi = ATM_VPI_UNSPEC;
+ instance->cached_vci = ATM_VCI_UNSPEC;
+ }
list_del(&vcc_data->list);
tasklet_enable(&instance->rx_channel.tasklet);
@@ -1146,6 +1211,16 @@ int usbatm_usb_probe(struct usb_interfac
__func__, urb->transfer_buffer,
urb->transfer_buffer_length, urb);
}
+ instance->cached_vpi = ATM_VPI_UNSPEC;
+ instance->cached_vci = ATM_VCI_UNSPEC;
+ instance->cell_buf = kmalloc(instance->rx_channel.stride, GFP_KERNEL);
+
+ if (!instance->cell_buf) {
+ dev_err(dev, "%s: no memory for cell buffer!\n", __func__);
+ error = -ENOMEM;
+ goto fail_unbind;
+ }
+
if (!(instance->flags & UDSL_SKIP_HEAVY_INIT) && driver->heavy_init) {
error = usbatm_heavy_init(instance);
} else {
@@ -1165,6 +1240,8 @@ int usbatm_usb_probe(struct usb_interfac
if (instance->driver->unbind)
instance->driver->unbind(instance, intf);
fail_free:
+ kfree(instance->cell_buf);
+
for (i = 0; i < num_rcv_urbs + num_snd_urbs; i++) {
if (instance->urbs[i])
kfree(instance->urbs[i]->transfer_buffer);
@@ -1236,6 +1313,8 @@ void usbatm_usb_disconnect(struct usb_in
usb_free_urb(instance->urbs[i]);
}
+ kfree(instance->cell_buf);
+
/* ATM finalize */
if (instance->atm_dev)
atm_dev_deregister(instance->atm_dev);
diff --git a/drivers/usb/atm/usbatm.h b/drivers/usb/atm/usbatm.h
index 0e2caa0..bdff534 100644
--- a/drivers/usb/atm/usbatm.h
+++ b/drivers/usb/atm/usbatm.h
@@ -187,6 +187,13 @@ struct usbatm_data {
struct sk_buff_head sndqueue;
struct sk_buff *current_skb; /* being emptied */
+ struct usbatm_vcc_data *cached_vcc;
+ int cached_vci;
+ short cached_vpi;
+
+ unsigned char *cell_buf; /* holds partial rx cell */
+ unsigned int buf_usage;
+
struct urb *urbs[0];
};
-------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
for problems? Stop! Download the new AJAX search engine that makes
searching your log files as easy as surfing the web. DOWNLOAD SPLUNK!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid3432&bid#0486&dat1642
_______________________________________________
linux-usb-devel@lists.sourceforge.net
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
