diff options
| author | Jay Fenlason <fenlason@redhat.com> | 2009-12-11 14:23:58 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-12-18 13:30:43 -0800 |
| commit | e6ebd01ffd7b79678dfdda1d3b5653e8aea3eb41 (patch) | |
| tree | 46135b074f89367ecb948519b11b44e5a30edbbc | |
| parent | 7a3390e41955ec09330821ba7b5231fc5b333453 (diff) | |
firewire: ohci: handle receive packets with a data length of zero
commit 8c0c0cc2d9f4c523fde04bdfe41e4380dec8ee54 upstream.
Queueing to receive an ISO packet with a payload length of zero
silently does nothing in dualbuffer mode, and crashes the kernel in
packet-per-buffer mode. Return an error in dualbuffer mode, because
the DMA controller won't let us do what we want, and work correctly in
packet-per-buffer mode.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/firewire/fw-ohci.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c index cd589cadbe01..68693104cd69 100644 --- a/drivers/firewire/fw-ohci.c +++ b/drivers/firewire/fw-ohci.c @@ -2146,6 +2146,13 @@ ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base, page = payload >> PAGE_SHIFT; offset = payload & ~PAGE_MASK; rest = p->payload_length; + /* + * The controllers I've tested have not worked correctly when + * second_req_count is zero. Rather than do something we know won't + * work, return an error + */ + if (rest == 0) + return -EINVAL; /* FIXME: make packet-per-buffer/dual-buffer a context option */ while (rest > 0) { @@ -2199,7 +2206,7 @@ ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base, unsigned long payload) { struct iso_context *ctx = container_of(base, struct iso_context, base); - struct descriptor *d = NULL, *pd = NULL; + struct descriptor *d, *pd; struct fw_iso_packet *p = packet; dma_addr_t d_bus, page_bus; u32 z, header_z, rest; @@ -2237,8 +2244,9 @@ ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base, d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d))); rest = payload_per_buffer; + pd = d; for (j = 1; j < z; j++) { - pd = d + j; + pd++; pd->control = cpu_to_le16(DESCRIPTOR_STATUS | DESCRIPTOR_INPUT_MORE); |