iwlwifi: handle DMA mapping failures

commit 7c34158231 upstream.

The RX replenish code doesn't handle DMA mapping failures,
which will cause issues if there actually is a failure. This
was reported by Shuah Khan who found a DMA mapping framework
warning ("device driver failed to check map error").

Reported-by: Shuah Khan <shuah.khan@hp.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[bwh: Backported to 3.2:
 - Adjust filename, context, indentation
 - Use bus(trans) instead of trans where necessary
 - Use hw_params(trans).rx_page_order instead of trans_pcie->rx_page_order]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
[wujg: Backported to 3.4:
 - Adjust context
 - Use trans instead of bus(trans)
 - Use hw_params(trans).rx_page_order instead of trans_pcie->rx_page_order]
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johannes Berg
2014-02-27 09:52:58 +08:00
committed by Greg Kroah-Hartman
parent af720fc6ae
commit f2da4cebef

View File

@ -315,6 +315,14 @@ static void iwlagn_rx_allocate(struct iwl_trans *trans, gfp_t priority)
rxb->page_dma = dma_map_page(trans->dev, page, 0,
PAGE_SIZE << hw_params(trans).rx_page_order,
DMA_FROM_DEVICE);
if (dma_mapping_error(trans->dev, rxb->page_dma)) {
rxb->page = NULL;
spin_lock_irqsave(&rxq->lock, flags);
list_add(&rxb->list, &rxq->rx_used);
spin_unlock_irqrestore(&rxq->lock, flags);
__free_pages(page, hw_params(trans).rx_page_order);
return;
}
/* dma address must be no more than 36 bits */
BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
/* and also 256 byte aligned! */
@ -450,8 +458,19 @@ static void iwl_rx_handle_rxbuf(struct iwl_trans *trans,
dma_map_page(trans->dev, rxb->page, 0,
PAGE_SIZE << hw_params(trans).rx_page_order,
DMA_FROM_DEVICE);
list_add_tail(&rxb->list, &rxq->rx_free);
rxq->free_count++;
if (dma_mapping_error(trans->dev, rxb->page_dma)) {
/*
* free the page(s) as well to not break
* the invariant that the items on the used
* list have no page(s)
*/
__free_pages(rxb->page, hw_params(trans).rx_page_order);
rxb->page = NULL;
list_add_tail(&rxb->list, &rxq->rx_used);
} else {
list_add_tail(&rxb->list, &rxq->rx_free);
rxq->free_count++;
}
} else
list_add_tail(&rxb->list, &rxq->rx_used);
spin_unlock_irqrestore(&rxq->lock, flags);