void async_tx_quiesce(struct dma_async_tx_descriptor **tx)
{
if (*tx) {
BUG_ON(async_tx_test_ack(*tx));
if (dma_wait_for_async_tx(*tx) == DMA_ERROR)
panic("DMA_ERROR waiting for transaction\n");
async_tx_ack(*tx);
*tx = NULL;
}
}
void
async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
struct async_submit_ctl *submit)
{
struct dma_async_tx_descriptor *depend_tx = submit->depend_tx;
tx->callback = submit->cb_fn;
tx->callback_param = submit->cb_param;
if (depend_tx) {
enum submit_disposition s;
BUG_ON(async_tx_test_ack(depend_tx) || txd_next(depend_tx) ||
txd_parent(tx));
txd_lock(depend_tx);
if (txd_parent(depend_tx)) {
if (depend_tx->chan == chan) {
txd_chain(depend_tx, tx);
s = ASYNC_TX_SUBMITTED;
} else
s = ASYNC_TX_CHANNEL_SWITCH;
} else {
if (depend_tx->chan == chan)
s = ASYNC_TX_DIRECT_SUBMIT;
else
s = ASYNC_TX_CHANNEL_SWITCH;
}
txd_unlock(depend_tx);
switch (s) {
case ASYNC_TX_SUBMITTED:
break;
case ASYNC_TX_CHANNEL_SWITCH:
async_tx_channel_switch(depend_tx, tx);
break;
case ASYNC_TX_DIRECT_SUBMIT:
txd_clear_parent(tx);
tx->tx_submit(tx);
break;
}
} else {
txd_clear_parent(tx);
tx->tx_submit(tx);
}
if (submit->flags & ASYNC_TX_ACK)
async_tx_ack(tx);
if (depend_tx)
async_tx_ack(depend_tx);
}
/**
* async_tx_quiesce - ensure tx is complete and freeable upon return
* @tx - transaction to quiesce
*/
void async_tx_quiesce(struct dma_async_tx_descriptor **tx)
{
if (*tx) {
/* if ack is already set then we cannot be sure
* we are referring to the correct operation
*/
BUG_ON(async_tx_test_ack(*tx));
if (dma_wait_for_async_tx(*tx) == DMA_ERROR)
panic("DMA_ERROR waiting for transaction\n");
async_tx_ack(*tx);
*tx = NULL;
}
}
/**
* async_xor - attempt to xor a set of blocks with a dma engine.
* xor_blocks always uses the dest as a source so the ASYNC_TX_XOR_ZERO_DST
* flag must be set to not include dest data in the calculation. The
* assumption with dma eninges is that they only use the destination
* buffer as a source when it is explicity specified in the source list.
* @dest: destination page
* @src_list: array of source pages (if the dest is also a source it must be
* at index zero). The contents of this array may be overwritten.
* @offset: offset in pages to start transaction
* @src_cnt: number of source pages
* @len: length in bytes
* @flags: ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DEST,
* ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
* @depend_tx: xor depends on the result of this transaction.
* @cb_fn: function to call when the xor completes
* @cb_param: parameter to pass to the callback routine
*/
struct dma_async_tx_descriptor *
async_xor(struct page *dest, struct page **src_list, unsigned int offset,
int src_cnt, size_t len, enum async_tx_flags flags,
struct dma_async_tx_descriptor *depend_tx,
dma_async_tx_callback cb_fn, void *cb_param)
{
struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_XOR,
&dest, 1, src_list,
src_cnt, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx = NULL;
dma_async_tx_callback _cb_fn;
void *_cb_param;
unsigned long local_flags;
int xor_src_cnt;
int i = 0, src_off = 0;
BUG_ON(src_cnt <= 1);
while (src_cnt) {
local_flags = flags;
if (device) { /* run the xor asynchronously */
xor_src_cnt = min(src_cnt, device->max_xor);
/* if we are submitting additional xors
* only set the callback on the last transaction
*/
if (src_cnt > xor_src_cnt) {
local_flags &= ~ASYNC_TX_ACK;
_cb_fn = NULL;
_cb_param = NULL;
} else {
_cb_fn = cb_fn;
_cb_param = cb_param;
}
tx = do_async_xor(device, chan, dest,
&src_list[src_off], offset,
xor_src_cnt, len, local_flags,
depend_tx, _cb_fn, _cb_param);
} else { /* run the xor synchronously */
/* in the sync case the dest is an implied source
* (assumes the dest is at the src_off index)
*/
if (flags & ASYNC_TX_XOR_DROP_DST) {
src_cnt--;
src_off++;
}
/* process up to 'MAX_XOR_BLOCKS' sources */
xor_src_cnt = min(src_cnt, MAX_XOR_BLOCKS);
/* if we are submitting additional xors
* only set the callback on the last transaction
*/
if (src_cnt > xor_src_cnt) {
local_flags &= ~ASYNC_TX_ACK;
_cb_fn = NULL;
_cb_param = NULL;
} else {
_cb_fn = cb_fn;
_cb_param = cb_param;
}
/* wait for any prerequisite operations */
if (depend_tx) {
/* if ack is already set then we cannot be sure
* we are referring to the correct operation
*/
BUG_ON(async_tx_test_ack(depend_tx));
if (dma_wait_for_async_tx(depend_tx) ==
DMA_ERROR)
panic("%s: DMA_ERROR waiting for "
"depend_tx\n",
__func__);
}
do_sync_xor(dest, &src_list[src_off], offset,
xor_src_cnt, len, local_flags, depend_tx,
_cb_fn, _cb_param);
}
/* the previous tx is hidden from the client,
* so ack it
*/
if (i && depend_tx)
async_tx_ack(depend_tx);
depend_tx = tx;
if (src_cnt > xor_src_cnt) {
/* drop completed sources */
src_cnt -= xor_src_cnt;
src_off += xor_src_cnt;
/* unconditionally preserve the destination */
flags &= ~ASYNC_TX_XOR_ZERO_DST;
/* use the intermediate result a source, but remember
* it's dropped, because it's implied, in the sync case
*/
src_list[--src_off] = dest;
src_cnt++;
flags |= ASYNC_TX_XOR_DROP_DST;
} else
src_cnt = 0;
i++;
}
return tx;
}
void
async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
struct async_submit_ctl *submit)
{
struct dma_async_tx_descriptor *depend_tx = submit->depend_tx;
tx->callback = submit->cb_fn;
tx->callback_param = submit->cb_param;
if (depend_tx) {
enum submit_disposition s;
/* sanity check the dependency chain:
* 1/ if ack is already set then we cannot be sure
* we are referring to the correct operation
* 2/ dependencies are 1:1 i.e. two transactions can
* not depend on the same parent
*/
BUG_ON(async_tx_test_ack(depend_tx) || txd_next(depend_tx) ||
txd_parent(tx));
/* the lock prevents async_tx_run_dependencies from missing
* the setting of ->next when ->parent != NULL
*/
txd_lock(depend_tx);
if (txd_parent(depend_tx)) {
/* we have a parent so we can not submit directly
* if we are staying on the same channel: append
* else: channel switch
*/
if (depend_tx->chan == chan) {
txd_chain(depend_tx, tx);
s = ASYNC_TX_SUBMITTED;
} else
s = ASYNC_TX_CHANNEL_SWITCH;
} else {
/* we do not have a parent so we may be able to submit
* directly if we are staying on the same channel
*/
if (depend_tx->chan == chan)
s = ASYNC_TX_DIRECT_SUBMIT;
else
s = ASYNC_TX_CHANNEL_SWITCH;
}
txd_unlock(depend_tx);
switch (s) {
case ASYNC_TX_SUBMITTED:
break;
case ASYNC_TX_CHANNEL_SWITCH:
async_tx_channel_switch(depend_tx, tx);
break;
case ASYNC_TX_DIRECT_SUBMIT:
txd_clear_parent(tx);
tx->tx_submit(tx);
break;
}
} else {
txd_clear_parent(tx);
tx->tx_submit(tx);
}
if (submit->flags & ASYNC_TX_ACK)
async_tx_ack(tx);
if (depend_tx)
async_tx_ack(depend_tx);
}
