#include <linux/raid/xor.h>
#include <linux/async_tx.h>
-static void
-do_async_xor(struct dma_async_tx_descriptor *tx, struct dma_device *device,
+/* do_async_xor - dma map the pages and perform the xor with an engine.
+ * This routine is marked __always_inline so it can be compiled away
+ * when CONFIG_DMA_ENGINE=n
+ */
+static __always_inline struct dma_async_tx_descriptor *
+do_async_xor(struct dma_device *device,
struct dma_chan *chan, struct page *dest, struct page **src_list,
unsigned int offset, unsigned 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)
{
- dma_addr_t dma_addr;
- enum dma_data_direction dir;
+ dma_addr_t dma_dest;
+ dma_addr_t *dma_src = (dma_addr_t *) src_list;
+ struct dma_async_tx_descriptor *tx;
int i;
+ unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0;
- pr_debug("%s: len: %zu\n", __FUNCTION__, len);
-
- dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
- DMA_NONE : DMA_FROM_DEVICE;
-
- dma_addr = dma_map_page(device->dev, dest, offset, len, dir);
- tx->tx_set_dest(dma_addr, tx, 0);
+ pr_debug("%s: len: %zu\n", __func__, len);
- dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
- DMA_NONE : DMA_TO_DEVICE;
+ dma_dest = dma_map_page(device->dev, dest, offset, len,
+ DMA_FROM_DEVICE);
- for (i = 0; i < src_cnt; i++) {
- dma_addr = dma_map_page(device->dev, src_list[i],
- offset, len, dir);
- tx->tx_set_src(dma_addr, tx, i);
+ for (i = 0; i < src_cnt; i++)
+ dma_src[i] = dma_map_page(device->dev, src_list[i], offset,
+ len, DMA_TO_DEVICE);
+
+ /* Since we have clobbered the src_list we are committed
+ * to doing this asynchronously. Drivers force forward progress
+ * in case they can not provide a descriptor
+ */
+ tx = device->device_prep_dma_xor(chan, dma_dest, dma_src, src_cnt, len,
+ dma_prep_flags);
+ if (!tx) {
+ if (depend_tx)
+ dma_wait_for_async_tx(depend_tx);
+
+ while (!tx)
+ tx = device->device_prep_dma_xor(chan, dma_dest,
+ dma_src, src_cnt, len,
+ dma_prep_flags);
}
async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
+
+ return tx;
}
static void
void *_dest;
int i;
- pr_debug("%s: len: %zu\n", __FUNCTION__, len);
+ pr_debug("%s: len: %zu\n", __func__, len);
/* reuse the 'src_list' array to convert to buffer pointers */
for (i = 0; i < src_cnt; i++)
* @src_cnt: number of source pages
* @len: length in bytes
* @flags: ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DEST,
- * ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
+ * 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 *depend_tx,
dma_async_tx_callback cb_fn, void *cb_param)
{
- struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_XOR);
+ 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, int_en;
+ int i = 0, src_off = 0;
BUG_ON(src_cnt <= 1);
_cb_param = cb_param;
}
- int_en = _cb_fn ? 1 : 0;
-
- tx = device->device_prep_dma_xor(
- chan, xor_src_cnt, len, int_en);
-
- if (tx) {
- do_async_xor(tx, device, chan, dest,
- &src_list[src_off], offset, xor_src_cnt, len,
- local_flags, depend_tx, _cb_fn,
- _cb_param);
- } else /* fall through */
- goto xor_sync;
+ 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 */
-xor_sync:
/* in the sync case the dest is an implied source
* (assumes the dest is at the src_off index)
*/
DMA_ERROR)
panic("%s: DMA_ERROR waiting for "
"depend_tx\n",
- __FUNCTION__);
+ __func__);
}
do_sync_xor(dest, &src_list[src_off], offset,
* @src_cnt: number of source pages
* @len: length in bytes
* @result: 0 if sum == 0 else non-zero
- * @flags: ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
+ * @flags: 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 *depend_tx,
dma_async_tx_callback cb_fn, void *cb_param)
{
- struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_ZERO_SUM);
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_ZERO_SUM,
+ &dest, 1, src_list,
+ src_cnt, len);
struct dma_device *device = chan ? chan->device : NULL;
- int int_en = cb_fn ? 1 : 0;
- struct dma_async_tx_descriptor *tx = device ?
- device->device_prep_dma_zero_sum(chan, src_cnt, len, result,
- int_en) : NULL;
- int i;
+ struct dma_async_tx_descriptor *tx = NULL;
BUG_ON(src_cnt <= 1);
- if (tx) {
- dma_addr_t dma_addr;
- enum dma_data_direction dir;
+ if (device && src_cnt <= device->max_xor) {
+ dma_addr_t *dma_src = (dma_addr_t *) src_list;
+ unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0;
+ int i;
+
+ pr_debug("%s: (async) len: %zu\n", __func__, len);
- pr_debug("%s: (async) len: %zu\n", __FUNCTION__, len);
+ for (i = 0; i < src_cnt; i++)
+ dma_src[i] = dma_map_page(device->dev, src_list[i],
+ offset, len, DMA_TO_DEVICE);
- dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
- DMA_NONE : DMA_TO_DEVICE;
+ tx = device->device_prep_dma_zero_sum(chan, dma_src, src_cnt,
+ len, result,
+ dma_prep_flags);
+ if (!tx) {
+ if (depend_tx)
+ dma_wait_for_async_tx(depend_tx);
- for (i = 0; i < src_cnt; i++) {
- dma_addr = dma_map_page(device->dev, src_list[i],
- offset, len, dir);
- tx->tx_set_src(dma_addr, tx, i);
+ while (!tx)
+ tx = device->device_prep_dma_zero_sum(chan,
+ dma_src, src_cnt, len, result,
+ dma_prep_flags);
}
async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
} else {
unsigned long xor_flags = flags;
- pr_debug("%s: (sync) len: %zu\n", __FUNCTION__, len);
+ pr_debug("%s: (sync) len: %zu\n", __func__, len);
xor_flags |= ASYNC_TX_XOR_DROP_DST;
xor_flags &= ~ASYNC_TX_ACK;
if (tx) {
if (dma_wait_for_async_tx(tx) == DMA_ERROR)
panic("%s: DMA_ERROR waiting for tx\n",
- __FUNCTION__);
+ __func__);
async_tx_ack(tx);
}
static int __init async_xor_init(void)
{
+ #ifdef CONFIG_DMA_ENGINE
+ /* To conserve stack space the input src_list (array of page pointers)
+ * is reused to hold the array of dma addresses passed to the driver.
+ * This conversion is only possible when dma_addr_t is less than the
+ * the size of a pointer. HIGHMEM64G is known to violate this
+ * assumption.
+ */
+ BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(struct page *));
+ #endif
+
return 0;
}
projects / linux-2.6-omap-h63xx.git / blobdiff