Merge branch 'rmk_cookie_fixes2' into next

Conflicts:
	drivers/dma/imx-dma.c
	drivers/dma/pl330.c

Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>

arch/arm/include/asm/hardware/iop_adma.h

@@ -49,7 +49,6 @@ struct iop_adma_device {
 /**
  * struct iop_adma_chan - internal representation of an ADMA device
  * @pending: allows batching of hardware operations
- * @completed_cookie: identifier for the most recently completed operation
  * @lock: serializes enqueue/dequeue operations to the slot pool
  * @mmr_base: memory mapped register base
  * @chain: device chain view of the descriptors
@@ -62,7 +61,6 @@ struct iop_adma_device {
  */
 struct iop_adma_chan {
 	int pending;
-	dma_cookie_t completed_cookie;
 	spinlock_t lock; /* protects the descriptor slot pool */
 	void __iomem *mmr_base;
 	struct list_head chain;

drivers/dma/amba-pl08x.c

@@ -85,6 +85,8 @@
 #include <linux/slab.h>
 #include <asm/hardware/pl080.h>
 
+#include "dmaengine.h"
+
 #define DRIVER_NAME	"pl08xdmac"
 
 static struct amba_driver pl08x_amba_driver;
@@ -919,13 +921,10 @@ static dma_cookie_t pl08x_tx_submit(struct dma_async_tx_descriptor *tx)
 	struct pl08x_dma_chan *plchan = to_pl08x_chan(tx->chan);
 	struct pl08x_txd *txd = to_pl08x_txd(tx);
 	unsigned long flags;
+	dma_cookie_t cookie;
 
 	spin_lock_irqsave(&plchan->lock, flags);
-
-	plchan->chan.cookie += 1;
-	if (plchan->chan.cookie < 0)
-		plchan->chan.cookie = 1;
-	tx->cookie = plchan->chan.cookie;
+	cookie = dma_cookie_assign(tx);
 
 	/* Put this onto the pending list */
 	list_add_tail(&txd->node, &plchan->pend_list);
@@ -945,7 +944,7 @@ static dma_cookie_t pl08x_tx_submit(struct dma_async_tx_descriptor *tx)
 
 	spin_unlock_irqrestore(&plchan->lock, flags);
 
-	return tx->cookie;
+	return cookie;
 }
 
 static struct dma_async_tx_descriptor *pl08x_prep_dma_interrupt(
@@ -965,31 +964,17 @@ static enum dma_status pl08x_dma_tx_status(struct dma_chan *chan,
 		dma_cookie_t cookie, struct dma_tx_state *txstate)
 {
 	struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
 	enum dma_status ret;
-	u32 bytesleft = 0;
-
-	last_used = plchan->chan.cookie;
-	last_complete = plchan->lc;
 
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
-	if (ret == DMA_SUCCESS) {
-		dma_set_tx_state(txstate, last_complete, last_used, 0);
+	ret = dma_cookie_status(chan, cookie, txstate);
+	if (ret == DMA_SUCCESS)
 		return ret;
-	}
 
 	/*
 	 * This cookie not complete yet
+	 * Get number of bytes left in the active transactions and queue
 	 */
-	last_used = plchan->chan.cookie;
-	last_complete = plchan->lc;
-
-	/* Get number of bytes left in the active transactions and queue */
-	bytesleft = pl08x_getbytes_chan(plchan);
-
-	dma_set_tx_state(txstate, last_complete, last_used,
-			 bytesleft);
+	dma_set_residue(txstate, pl08x_getbytes_chan(plchan));
 
 	if (plchan->state == PL08X_CHAN_PAUSED)
 		return DMA_PAUSED;
@@ -1543,7 +1528,7 @@ static void pl08x_tasklet(unsigned long data)
 
 	if (txd) {
 		/* Update last completed */
-		plchan->lc = txd->tx.cookie;
+		dma_cookie_complete(&txd->tx);
 	}
 
 	/* If a new descriptor is queued, set it up plchan->at is NULL here */
@@ -1724,8 +1709,7 @@ static int pl08x_dma_init_virtual_channels(struct pl08x_driver_data *pl08x,
 			 chan->name);
 
 		chan->chan.device = dmadev;
-		chan->chan.cookie = 0;
-		chan->lc = 0;
+		dma_cookie_init(&chan->chan);
 
 		spin_lock_init(&chan->lock);
 		INIT_LIST_HEAD(&chan->pend_list);

drivers/dma/at_hdmac.c

@@ -27,6 +27,7 @@
 #include <linux/of_device.h>
 
 #include "at_hdmac_regs.h"
+#include "dmaengine.h"
 
 /*
  * Glossary
@@ -191,27 +192,6 @@ static void atc_desc_chain(struct at_desc **first, struct at_desc **prev,
 	*prev = desc;
 }
 
-/**
- * atc_assign_cookie - compute and assign new cookie
- * @atchan: channel we work on
- * @desc: descriptor to assign cookie for
- *
- * Called with atchan->lock held and bh disabled
- */
-static dma_cookie_t
-atc_assign_cookie(struct at_dma_chan *atchan, struct at_desc *desc)
-{
-	dma_cookie_t cookie = atchan->chan_common.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	atchan->chan_common.cookie = cookie;
-	desc->txd.cookie = cookie;
-
-	return cookie;
-}
-
 /**
  * atc_dostart - starts the DMA engine for real
  * @atchan: the channel we want to start
@@ -269,7 +249,7 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
 	dev_vdbg(chan2dev(&atchan->chan_common),
 		"descriptor %u complete\n", txd->cookie);
 
-	atchan->completed_cookie = txd->cookie;
+	dma_cookie_complete(txd);
 
 	/* move children to free_list */
 	list_splice_init(&desc->tx_list, &atchan->free_list);
@@ -547,7 +527,7 @@ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx)
 	unsigned long		flags;
 
 	spin_lock_irqsave(&atchan->lock, flags);
-	cookie = atc_assign_cookie(atchan, desc);
+	cookie = dma_cookie_assign(tx);
 
 	if (list_empty(&atchan->active_list)) {
 		dev_vdbg(chan2dev(tx->chan), "tx_submit: started %u\n",
@@ -1016,26 +996,20 @@ atc_tx_status(struct dma_chan *chan,
 
 	spin_lock_irqsave(&atchan->lock, flags);
 
-	last_complete = atchan->completed_cookie;
-	last_used = chan->cookie;
-
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret != DMA_SUCCESS) {
 		atc_cleanup_descriptors(atchan);
 
-		last_complete = atchan->completed_cookie;
-		last_used = chan->cookie;
-
-		ret = dma_async_is_complete(cookie, last_complete, last_used);
+		ret = dma_cookie_status(chan, cookie, txstate);
 	}
 
+	last_complete = chan->completed_cookie;
+	last_used = chan->cookie;
+
 	spin_unlock_irqrestore(&atchan->lock, flags);
 
 	if (ret != DMA_SUCCESS)
-		dma_set_tx_state(txstate, last_complete, last_used,
-			atc_first_active(atchan)->len);
-	else
-		dma_set_tx_state(txstate, last_complete, last_used, 0);
+		dma_set_residue(txstate, atc_first_active(atchan)->len);
 
 	if (atc_chan_is_paused(atchan))
 		ret = DMA_PAUSED;
@@ -1129,7 +1103,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irqsave(&atchan->lock, flags);
 	atchan->descs_allocated = i;
 	list_splice(&tmp_list, &atchan->free_list);
-	atchan->completed_cookie = chan->cookie = 1;
+	dma_cookie_init(chan);
 	spin_unlock_irqrestore(&atchan->lock, flags);
 
 	/* channel parameters */
@@ -1329,7 +1303,7 @@ static int __init at_dma_probe(struct platform_device *pdev)
 		struct at_dma_chan	*atchan = &atdma->chan[i];
 
 		atchan->chan_common.device = &atdma->dma_common;
-		atchan->chan_common.cookie = atchan->completed_cookie = 1;
+		dma_cookie_init(&atchan->chan_common);
 		list_add_tail(&atchan->chan_common.device_node,
 				&atdma->dma_common.channels);
 

drivers/dma/at_hdmac_regs.h

@@ -208,7 +208,6 @@ enum atc_status {
  * @save_dscr: for cyclic operations, preserve next descriptor address in
  *             the cyclic list on suspend/resume cycle
  * @lock: serializes enqueue/dequeue operations to descriptors lists
- * @completed_cookie: identifier for the most recently completed operation
  * @active_list: list of descriptors dmaengine is being running on
  * @queue: list of descriptors ready to be submitted to engine
  * @free_list: list of descriptors usable by the channel
@@ -227,7 +226,6 @@ struct at_dma_chan {
 	spinlock_t		lock;
 
 	/* these other elements are all protected by lock */
-	dma_cookie_t		completed_cookie;
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;

drivers/dma/coh901318.c

@@ -24,6 +24,7 @@
 #include <mach/coh901318.h>
 
 #include "coh901318_lli.h"
+#include "dmaengine.h"
 
 #define COHC_2_DEV(cohc) (&cohc->chan.dev->device)
 
@@ -59,7 +60,6 @@ struct coh901318_base {
 struct coh901318_chan {
 	spinlock_t lock;
 	int allocated;
-	int completed;
 	int id;
 	int stopped;
 
@@ -318,20 +318,6 @@ static int coh901318_prep_linked_list(struct coh901318_chan *cohc,
 
 	return 0;
 }
-static dma_cookie_t
-coh901318_assign_cookie(struct coh901318_chan *cohc,
-			struct coh901318_desc *cohd)
-{
-	dma_cookie_t cookie = cohc->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	cohc->chan.cookie = cookie;
-	cohd->desc.cookie = cookie;
-
-	return cookie;
-}
 
 static struct coh901318_desc *
 coh901318_desc_get(struct coh901318_chan *cohc)
@@ -705,7 +691,7 @@ static void dma_tasklet(unsigned long data)
 	callback_param = cohd_fin->desc.callback_param;
 
 	/* sign this job as completed on the channel */
-	cohc->completed = cohd_fin->desc.cookie;
+	dma_cookie_complete(&cohd_fin->desc);
 
 	/* release the lli allocation and remove the descriptor */
 	coh901318_lli_free(&cohc->base->pool, &cohd_fin->lli);
@@ -929,7 +915,7 @@ static int coh901318_alloc_chan_resources(struct dma_chan *chan)
 	coh901318_config(cohc, NULL);
 
 	cohc->allocated = 1;
-	cohc->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 
 	spin_unlock_irqrestore(&cohc->lock, flags);
 
@@ -966,16 +952,16 @@ coh901318_tx_submit(struct dma_async_tx_descriptor *tx)
 						   desc);
 	struct coh901318_chan *cohc = to_coh901318_chan(tx->chan);
 	unsigned long flags;
+	dma_cookie_t cookie;
 
 	spin_lock_irqsave(&cohc->lock, flags);
-
-	tx->cookie = coh901318_assign_cookie(cohc, cohd);
+	cookie = dma_cookie_assign(tx);
 
 	coh901318_desc_queue(cohc, cohd);
 
 	spin_unlock_irqrestore(&cohc->lock, flags);
 
-	return tx->cookie;
+	return cookie;
 }
 
 static struct dma_async_tx_descriptor *
@@ -1165,17 +1151,12 @@ coh901318_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 		 struct dma_tx_state *txstate)
 {
 	struct coh901318_chan *cohc = to_coh901318_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
-	int ret;
-
-	last_complete = cohc->completed;
-	last_used = chan->cookie;
+	enum dma_status ret;
 
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
+	/* FIXME: should be conditional on ret != DMA_SUCCESS? */
+	dma_set_residue(txstate, coh901318_get_bytes_left(chan));
 
-	dma_set_tx_state(txstate, last_complete, last_used,
-			 coh901318_get_bytes_left(chan));
 	if (ret == DMA_IN_PROGRESS && cohc->stopped)
 		ret = DMA_PAUSED;
 

drivers/dma/dmaengine.h

@@ -0,0 +1,89 @@
+/*
+ * The contents of this file are private to DMA engine drivers, and is not
+ * part of the API to be used by DMA engine users.
+ */
+#ifndef DMAENGINE_H
+#define DMAENGINE_H
+
+#include <linux/bug.h>
+#include <linux/dmaengine.h>
+
+/**
+ * dma_cookie_init - initialize the cookies for a DMA channel
+ * @chan: dma channel to initialize
+ */
+static inline void dma_cookie_init(struct dma_chan *chan)
+{
+	chan->cookie = DMA_MIN_COOKIE;
+	chan->completed_cookie = DMA_MIN_COOKIE;
+}
+
+/**
+ * dma_cookie_assign - assign a DMA engine cookie to the descriptor
+ * @tx: descriptor needing cookie
+ *
+ * Assign a unique non-zero per-channel cookie to the descriptor.
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx)
+{
+	struct dma_chan *chan = tx->chan;
+	dma_cookie_t cookie;
+
+	cookie = chan->cookie + 1;
+	if (cookie < DMA_MIN_COOKIE)
+		cookie = DMA_MIN_COOKIE;
+	tx->cookie = chan->cookie = cookie;
+
+	return cookie;
+}
+
+/**
+ * dma_cookie_complete - complete a descriptor
+ * @tx: descriptor to complete
+ *
+ * Mark this descriptor complete by updating the channels completed
+ * cookie marker.  Zero the descriptors cookie to prevent accidental
+ * repeated completions.
+ *
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx)
+{
+	BUG_ON(tx->cookie < DMA_MIN_COOKIE);
+	tx->chan->completed_cookie = tx->cookie;
+	tx->cookie = 0;
+}
+
+/**
+ * dma_cookie_status - report cookie status
+ * @chan: dma channel
+ * @cookie: cookie we are interested in
+ * @state: dma_tx_state structure to return last/used cookies
+ *
+ * Report the status of the cookie, filling in the state structure if
+ * non-NULL.  No locking is required.
+ */
+static inline enum dma_status dma_cookie_status(struct dma_chan *chan,
+	dma_cookie_t cookie, struct dma_tx_state *state)
+{
+	dma_cookie_t used, complete;
+
+	used = chan->cookie;
+	complete = chan->completed_cookie;
+	barrier();
+	if (state) {
+		state->last = complete;
+		state->used = used;
+		state->residue = 0;
+	}
+	return dma_async_is_complete(cookie, complete, used);
+}
+
+static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)
+{
+	if (state)
+		state->residue = residue;
+}
+
+#endif

drivers/dma/dw_dmac.c

@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 
 #include "dw_dmac_regs.h"
+#include "dmaengine.h"
 
 /*
  * This supports the Synopsys "DesignWare AHB Central DMA Controller",
@@ -156,21 +157,6 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
 	}
 }
 
-/* Called with dwc->lock held and bh disabled */
-static dma_cookie_t
-dwc_assign_cookie(struct dw_dma_chan *dwc, struct dw_desc *desc)
-{
-	dma_cookie_t cookie = dwc->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	dwc->chan.cookie = cookie;
-	desc->txd.cookie = cookie;
-
-	return cookie;
-}
-
 static void dwc_initialize(struct dw_dma_chan *dwc)
 {
 	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
@@ -249,7 +235,7 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
 	dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie);
 
 	spin_lock_irqsave(&dwc->lock, flags);
-	dwc->completed = txd->cookie;
+	dma_cookie_complete(txd);
 	if (callback_required) {
 		callback = txd->callback;
 		param = txd->callback_param;
@@ -602,7 +588,7 @@ static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
 	unsigned long		flags;
 
 	spin_lock_irqsave(&dwc->lock, flags);
-	cookie = dwc_assign_cookie(dwc, desc);
+	cookie = dma_cookie_assign(tx);
 
 	/*
 	 * REVISIT: We should attempt to chain as many descriptors as
@@ -993,28 +979,17 @@ dwc_tx_status(struct dma_chan *chan,
 	      struct dma_tx_state *txstate)
 {
 	struct dw_dma_chan	*dwc = to_dw_dma_chan(chan);
-	dma_cookie_t		last_used;
-	dma_cookie_t		last_complete;
-	int			ret;
-
-	last_complete = dwc->completed;
-	last_used = chan->cookie;
+	enum dma_status		ret;
 
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret != DMA_SUCCESS) {
 		dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
 
-		last_complete = dwc->completed;
-		last_used = chan->cookie;
-
-		ret = dma_async_is_complete(cookie, last_complete, last_used);
+		ret = dma_cookie_status(chan, cookie, txstate);
 	}
 
 	if (ret != DMA_SUCCESS)
-		dma_set_tx_state(txstate, last_complete, last_used,
-				dwc_first_active(dwc)->len);
-	else
-		dma_set_tx_state(txstate, last_complete, last_used, 0);
+		dma_set_residue(txstate, dwc_first_active(dwc)->len);
 
 	if (dwc->paused)
 		return DMA_PAUSED;
@@ -1046,7 +1021,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
 		return -EIO;
 	}
 
-	dwc->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 
 	/*
 	 * NOTE: some controllers may have additional features that we
@@ -1474,7 +1449,7 @@ static int __init dw_probe(struct platform_device *pdev)
 		struct dw_dma_chan	*dwc = &dw->chan[i];
 
 		dwc->chan.device = &dw->dma;
-		dwc->chan.cookie = dwc->completed = 1;
+		dma_cookie_init(&dwc->chan);
 		if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING)
 			list_add_tail(&dwc->chan.device_node,
 					&dw->dma.channels);

drivers/dma/dw_dmac_regs.h

@@ -158,7 +158,6 @@ struct dw_dma_chan {
 
 	/* these other elements are all protected by lock */
 	unsigned long		flags;
-	dma_cookie_t		completed;
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;

drivers/dma/ep93xx_dma.c

@@ -28,6 +28,8 @@
 
 #include <mach/dma.h>
 
+#include "dmaengine.h"
+
 /* M2P registers */
 #define M2P_CONTROL			0x0000
 #define M2P_CONTROL_STALLINT		BIT(0)
@@ -122,7 +124,6 @@ struct ep93xx_dma_desc {
  * @lock: lock protecting the fields following
  * @flags: flags for the channel
  * @buffer: which buffer to use next (0/1)
- * @last_completed: last completed cookie value
  * @active: flattened chain of descriptors currently being processed
  * @queue: pending descriptors which are handled next
  * @free_list: list of free descriptors which can be used
@@ -157,7 +158,6 @@ struct ep93xx_dma_chan {
 #define EP93XX_DMA_IS_CYCLIC		0
 
 	int				buffer;
-	dma_cookie_t			last_completed;
 	struct list_head		active;
 	struct list_head		queue;
 	struct list_head		free_list;
@@ -703,7 +703,7 @@ static void ep93xx_dma_tasklet(unsigned long data)
 	desc = ep93xx_dma_get_active(edmac);
 	if (desc) {
 		if (desc->complete) {
-			edmac->last_completed = desc->txd.cookie;
+			dma_cookie_complete(&desc->txd);
 			list_splice_init(&edmac->active, &list);
 		}
 		callback = desc->txd.callback;
@@ -783,17 +783,10 @@ static dma_cookie_t ep93xx_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 	unsigned long flags;
 
 	spin_lock_irqsave(&edmac->lock, flags);
-
-	cookie = edmac->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
+	cookie = dma_cookie_assign(tx);
 
 	desc = container_of(tx, struct ep93xx_dma_desc, txd);
 
-	edmac->chan.cookie = cookie;
-	desc->txd.cookie = cookie;
-
 	/*
 	 * If nothing is currently prosessed, we push this descriptor
 	 * directly to the hardware. Otherwise we put the descriptor
@@ -861,8 +854,7 @@ static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan)
 		goto fail_clk_disable;
 
 	spin_lock_irq(&edmac->lock);
-	edmac->last_completed = 1;
-	edmac->chan.cookie = 1;
+	dma_cookie_init(&edmac->chan);
 	ret = edmac->edma->hw_setup(edmac);
 	spin_unlock_irq(&edmac->lock);
 
@@ -1248,18 +1240,13 @@ static enum dma_status ep93xx_dma_tx_status(struct dma_chan *chan,
 					    struct dma_tx_state *state)
 {
 	struct ep93xx_dma_chan *edmac = to_ep93xx_dma_chan(chan);
-	dma_cookie_t last_used, last_completed;
 	enum dma_status ret;
 	unsigned long flags;
 
 	spin_lock_irqsave(&edmac->lock, flags);
-	last_used = chan->cookie;
-	last_completed = edmac->last_completed;
+	ret = dma_cookie_status(chan, cookie, state);
 	spin_unlock_irqrestore(&edmac->lock, flags);
 
-	ret = dma_async_is_complete(cookie, last_completed, last_used);
-	dma_set_tx_state(state, last_completed, last_used, 0);
-
 	return ret;
 }
 

drivers/dma/fsldma.c

@@ -35,6 +35,7 @@
 #include <linux/dmapool.h>
 #include <linux/of_platform.h>
 
+#include "dmaengine.h"
 #include "fsldma.h"
 
 #define chan_dbg(chan, fmt, arg...)					\
@@ -413,17 +414,10 @@ static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 	 * assign cookies to all of the software descriptors
 	 * that make up this transaction
 	 */
-	cookie = chan->common.cookie;
 	list_for_each_entry(child, &desc->tx_list, node) {
-		cookie++;
-		if (cookie < DMA_MIN_COOKIE)
-			cookie = DMA_MIN_COOKIE;
-
-		child->async_tx.cookie = cookie;
+		cookie = dma_cookie_assign(&child->async_tx);
 	}
 
-	chan->common.cookie = cookie;
-
 	/* put this transaction onto the tail of the pending queue */
 	append_ld_queue(chan, desc);
 
@@ -984,19 +978,14 @@ static enum dma_status fsl_tx_status(struct dma_chan *dchan,
 					struct dma_tx_state *txstate)
 {
 	struct fsldma_chan *chan = to_fsl_chan(dchan);
-	dma_cookie_t last_complete;
-	dma_cookie_t last_used;
+	enum dma_status ret;
 	unsigned long flags;
 
 	spin_lock_irqsave(&chan->desc_lock, flags);
-
-	last_complete = chan->completed_cookie;
-	last_used = dchan->cookie;
-
+	ret = dma_cookie_status(dchan, cookie, txstate);
 	spin_unlock_irqrestore(&chan->desc_lock, flags);
 
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return ret;
 }
 
 /*----------------------------------------------------------------------------*/
@@ -1087,8 +1076,8 @@ static void dma_do_tasklet(unsigned long data)
 
 		desc = to_fsl_desc(chan->ld_running.prev);
 		cookie = desc->async_tx.cookie;
+		dma_cookie_complete(&desc->async_tx);
 
-		chan->completed_cookie = cookie;
 		chan_dbg(chan, "completed_cookie=%d\n", cookie);
 	}
 
@@ -1303,6 +1292,7 @@ static int __devinit fsl_dma_chan_probe(struct fsldma_device *fdev,
 	chan->idle = true;
 
 	chan->common.device = &fdev->common;
+	dma_cookie_init(&chan->common);
 
 	/* find the IRQ line, if it exists in the device tree */
 	chan->irq = irq_of_parse_and_map(node, 0);

drivers/dma/fsldma.h

@@ -137,7 +137,6 @@ struct fsldma_device {
 struct fsldma_chan {
 	char name[8];			/* Channel name */
 	struct fsldma_chan_regs __iomem *regs;
-	dma_cookie_t completed_cookie;	/* The maximum cookie completed */
 	spinlock_t desc_lock;		/* Descriptor operation lock */
 	struct list_head ld_pending;	/* Link descriptors queue */
 	struct list_head ld_running;	/* Link descriptors queue */

drivers/dma/imx-dma.c

@@ -32,6 +32,7 @@
 #include <mach/dma-v1.h>
 #include <mach/hardware.h>
 
+#include "dmaengine.h"
 #define IMXDMA_MAX_CHAN_DESCRIPTORS	16
 
 enum  imxdma_prep_type {
@@ -77,7 +78,8 @@ struct imxdma_channel {
 	u32				watermark_level;
 	struct dma_chan			chan;
 	spinlock_t			lock;
-	dma_cookie_t			last_completed;
+	struct dma_async_tx_descriptor	desc;
+	enum dma_status			status;
 	int				dma_request;
 	struct scatterlist		*sg_list;
 };
@@ -192,7 +194,7 @@ static void imxdma_tasklet(unsigned long data)
 	if (desc->desc.callback)
 		desc->desc.callback(desc->desc.callback_param);
 
-	imxdmac->last_completed = desc->desc.cookie;
+	dma_cookie_complete(&desc->desc);
 
 	/* If we are dealing with a cyclic descriptor keep it on ld_active */
 	if (imxdma_chan_is_doing_cyclic(imxdmac))
@@ -276,31 +278,7 @@ static enum dma_status imxdma_tx_status(struct dma_chan *chan,
 					    dma_cookie_t cookie,
 					    struct dma_tx_state *txstate)
 {
-	struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
-	dma_cookie_t last_used;
-	enum dma_status ret;
-	unsigned long flags;
-
-	spin_lock_irqsave(&imxdmac->lock, flags);
-	last_used = chan->cookie;
-
-	ret = dma_async_is_complete(cookie, imxdmac->last_completed, last_used);
-	dma_set_tx_state(txstate, imxdmac->last_completed, last_used, 0);
-	spin_unlock_irqrestore(&imxdmac->lock, flags);
-
-	return ret;
-}
-
-static dma_cookie_t imxdma_assign_cookie(struct imxdma_channel *imxdma)
-{
-	dma_cookie_t cookie = imxdma->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	imxdma->chan.cookie = cookie;
-
-	return cookie;
+	return dma_cookie_status(chan, cookie, txstate);
 }
 
 static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
@@ -310,11 +288,7 @@ static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
 	unsigned long flags;
 
 	spin_lock_irqsave(&imxdmac->lock, flags);
-
-	list_move_tail(imxdmac->ld_free.next, &imxdmac->ld_queue);
-	cookie = imxdma_assign_cookie(imxdmac);
-	tx->cookie = cookie;
-
+	cookie = dma_cookie_assign(tx);
 	spin_unlock_irqrestore(&imxdmac->lock, flags);
 
 	return cookie;
@@ -583,6 +557,7 @@ static int __init imxdma_probe(struct platform_device *pdev)
 		tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
 			     (unsigned long)imxdmac);
 		imxdmac->chan.device = &imxdma->dma_device;
+		dma_cookie_init(&imxdmac->chan);
 		imxdmac->channel = i;
 
 		/* Add the channel to the DMAC list */

drivers/dma/imx-sdma.c

@@ -43,6 +43,8 @@
 #include <mach/dma.h>
 #include <mach/hardware.h>
 
+#include "dmaengine.h"
+
 /* SDMA registers */
 #define SDMA_H_C0PTR		0x000
 #define SDMA_H_INTR		0x004
@@ -267,7 +269,6 @@ struct sdma_channel {
 	struct dma_chan			chan;
 	spinlock_t			lock;
 	struct dma_async_tx_descriptor	desc;
-	dma_cookie_t			last_completed;
 	enum dma_status			status;
 	unsigned int			chn_count;
 	unsigned int			chn_real_count;
@@ -529,7 +530,7 @@ static void mxc_sdma_handle_channel_normal(struct sdma_channel *sdmac)
 	else
 		sdmac->status = DMA_SUCCESS;
 
-	sdmac->last_completed = sdmac->desc.cookie;
+	dma_cookie_complete(&sdmac->desc);
 	if (sdmac->desc.callback)
 		sdmac->desc.callback(sdmac->desc.callback_param);
 }
@@ -814,19 +815,6 @@ out:
 	return ret;
 }
 
-static dma_cookie_t sdma_assign_cookie(struct sdma_channel *sdmac)
-{
-	dma_cookie_t cookie = sdmac->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	sdmac->chan.cookie = cookie;
-	sdmac->desc.cookie = cookie;
-
-	return cookie;
-}
-
 static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
 {
 	return container_of(chan, struct sdma_channel, chan);
@@ -840,7 +828,7 @@ static dma_cookie_t sdma_tx_submit(struct dma_async_tx_descriptor *tx)
 
 	spin_lock_irqsave(&sdmac->lock, flags);
 
-	cookie = sdma_assign_cookie(sdmac);
+	cookie = dma_cookie_assign(tx);
 
 	spin_unlock_irqrestore(&sdmac->lock, flags);
 
@@ -1127,7 +1115,7 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
 
 	last_used = chan->cookie;
 
-	dma_set_tx_state(txstate, sdmac->last_completed, last_used,
+	dma_set_tx_state(txstate, chan->completed_cookie, last_used,
 			sdmac->chn_count - sdmac->chn_real_count);
 
 	return sdmac->status;
@@ -1368,6 +1356,7 @@ static int __init sdma_probe(struct platform_device *pdev)
 		spin_lock_init(&sdmac->lock);
 
 		sdmac->chan.device = &sdma->dma_device;
+		dma_cookie_init(&sdmac->chan);
 		sdmac->channel = i;
 
 		/*

drivers/dma/intel_mid_dma.c

@@ -29,6 +29,8 @@
 #include <linux/intel_mid_dma.h>
 #include <linux/module.h>
 
+#include "dmaengine.h"
+
 #define MAX_CHAN	4 /*max ch across controllers*/
 #include "intel_mid_dma_regs.h"
 
@@ -288,7 +290,7 @@ static void midc_descriptor_complete(struct intel_mid_dma_chan *midc,
 	struct intel_mid_dma_lli	*llitem;
 	void *param_txd = NULL;
 
-	midc->completed = txd->cookie;
+	dma_cookie_complete(txd);
 	callback_txd = txd->callback;
 	param_txd = txd->callback_param;
 
@@ -434,14 +436,7 @@ static dma_cookie_t intel_mid_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 	dma_cookie_t		cookie;
 
 	spin_lock_bh(&midc->lock);
-	cookie = midc->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	midc->chan.cookie = cookie;
-	desc->txd.cookie = cookie;
-
+	cookie = dma_cookie_assign(tx);
 
 	if (list_empty(&midc->active_list))
 		list_add_tail(&desc->desc_node, &midc->active_list);
@@ -482,31 +477,18 @@ static enum dma_status intel_mid_dma_tx_status(struct dma_chan *chan,
 						dma_cookie_t cookie,
 						struct dma_tx_state *txstate)
 {
-	struct intel_mid_dma_chan	*midc = to_intel_mid_dma_chan(chan);
-	dma_cookie_t		last_used;
-	dma_cookie_t		last_complete;
-	int				ret;
-
-	last_complete = midc->completed;
-	last_used = chan->cookie;
+	struct intel_mid_dma_chan *midc = to_intel_mid_dma_chan(chan);
+	enum dma_status ret;
 
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret != DMA_SUCCESS) {
 		spin_lock_bh(&midc->lock);
 		midc_scan_descriptors(to_middma_device(chan->device), midc);
 		spin_unlock_bh(&midc->lock);
 
-		last_complete = midc->completed;
-		last_used = chan->cookie;
-
-		ret = dma_async_is_complete(cookie, last_complete, last_used);
+		ret = dma_cookie_status(chan, cookie, txstate);
 	}
 
-	if (txstate) {
-		txstate->last = last_complete;
-		txstate->used = last_used;
-		txstate->residue = 0;
-	}
 	return ret;
 }
 
@@ -886,7 +868,7 @@ static int intel_mid_dma_alloc_chan_resources(struct dma_chan *chan)
 		pm_runtime_put(&mid->pdev->dev);
 		return -EIO;
 	}
-	midc->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 
 	spin_lock_bh(&midc->lock);
 	while (midc->descs_allocated < DESCS_PER_CHANNEL) {
@@ -1119,7 +1101,7 @@ static int mid_setup_dma(struct pci_dev *pdev)
 		struct intel_mid_dma_chan *midch = &dma->ch[i];
 
 		midch->chan.device = &dma->common;
-		midch->chan.cookie =  1;
+		dma_cookie_init(&midch->chan);
 		midch->ch_id = dma->chan_base + i;
 		pr_debug("MDMA:Init CH %d, ID %d\n", i, midch->ch_id);
 

drivers/dma/intel_mid_dma_regs.h

@@ -165,7 +165,6 @@ union intel_mid_dma_cfg_hi {
  * @dma_base: MMIO register space DMA engine base pointer
  * @ch_id: DMA channel id
  * @lock: channel spinlock
- * @completed: DMA cookie
  * @active_list: current active descriptors
  * @queue: current queued up descriptors
  * @free_list: current free descriptors
@@ -183,7 +182,6 @@ struct intel_mid_dma_chan {
 	void __iomem		*dma_base;
 	int			ch_id;
 	spinlock_t		lock;
-	dma_cookie_t		completed;
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;

drivers/dma/ioat/dma.c

@@ -40,6 +40,8 @@
 #include "registers.h"
 #include "hw.h"
 
+#include "../dmaengine.h"
+
 int ioat_pending_level = 4;
 module_param(ioat_pending_level, int, 0644);
 MODULE_PARM_DESC(ioat_pending_level,
@@ -107,6 +109,7 @@ void ioat_init_channel(struct ioatdma_device *device, struct ioat_chan_common *c
 	chan->reg_base = device->reg_base + (0x80 * (idx + 1));
 	spin_lock_init(&chan->cleanup_lock);
 	chan->common.device = dma;
+	dma_cookie_init(&chan->common);
 	list_add_tail(&chan->common.device_node, &dma->channels);
 	device->idx[idx] = chan;
 	init_timer(&chan->timer);
@@ -235,12 +238,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
 
 	spin_lock_bh(&ioat->desc_lock);
 	/* cookie incr and addition to used_list must be atomic */
-	cookie = c->cookie;
-	cookie++;
-	if (cookie < 0)
-		cookie = 1;
-	c->cookie = cookie;
-	tx->cookie = cookie;
+	cookie = dma_cookie_assign(tx);
 	dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie);
 
 	/* write address into NextDescriptor field of last desc in chain */
@@ -603,8 +601,7 @@ static void __cleanup(struct ioat_dma_chan *ioat, unsigned long phys_complete)
 		 */
 		dump_desc_dbg(ioat, desc);
 		if (tx->cookie) {
-			chan->completed_cookie = tx->cookie;
-			tx->cookie = 0;
+			dma_cookie_complete(tx);
 			ioat_dma_unmap(chan, tx->flags, desc->len, desc->hw);
 			ioat->active -= desc->hw->tx_cnt;
 			if (tx->callback) {
@@ -733,13 +730,15 @@ ioat_dma_tx_status(struct dma_chan *c, dma_cookie_t cookie,
 {
 	struct ioat_chan_common *chan = to_chan_common(c);
 	struct ioatdma_device *device = chan->device;
+	enum dma_status ret;
 
-	if (ioat_tx_status(c, cookie, txstate) == DMA_SUCCESS)
-		return DMA_SUCCESS;
+	ret = dma_cookie_status(c, cookie, txstate);
+	if (ret == DMA_SUCCESS)
+		return ret;
 
 	device->cleanup_fn((unsigned long) c);
 
-	return ioat_tx_status(c, cookie, txstate);
+	return dma_cookie_status(c, cookie, txstate);
 }
 
 static void ioat1_dma_start_null_desc(struct ioat_dma_chan *ioat)

drivers/dma/ioat/dma.h

@@ -90,7 +90,6 @@ struct ioat_chan_common {
 	void __iomem *reg_base;
 	unsigned long last_completion;
 	spinlock_t cleanup_lock;
-	dma_cookie_t completed_cookie;
 	unsigned long state;
 	#define IOAT_COMPLETION_PENDING 0
 	#define IOAT_COMPLETION_ACK 1
@@ -143,28 +142,6 @@ static inline struct ioat_dma_chan *to_ioat_chan(struct dma_chan *c)
 	return container_of(chan, struct ioat_dma_chan, base);
 }
 
-/**
- * ioat_tx_status - poll the status of an ioat transaction
- * @c: channel handle
- * @cookie: transaction identifier
- * @txstate: if set, updated with the transaction state
- */
-static inline enum dma_status
-ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
-		 struct dma_tx_state *txstate)
-{
-	struct ioat_chan_common *chan = to_chan_common(c);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
-
-	last_used = c->cookie;
-	last_complete = chan->completed_cookie;
-
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
-	return dma_async_is_complete(cookie, last_complete, last_used);
-}
-
 /* wrapper around hardware descriptor format + additional software fields */
 
 /**

drivers/dma/ioat/dma_v2.c

@@ -41,6 +41,8 @@
 #include "registers.h"
 #include "hw.h"
 
+#include "../dmaengine.h"
+
 int ioat_ring_alloc_order = 8;
 module_param(ioat_ring_alloc_order, int, 0644);
 MODULE_PARM_DESC(ioat_ring_alloc_order,
@@ -147,8 +149,7 @@ static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete)
 		dump_desc_dbg(ioat, desc);
 		if (tx->cookie) {
 			ioat_dma_unmap(chan, tx->flags, desc->len, desc->hw);
-			chan->completed_cookie = tx->cookie;
-			tx->cookie = 0;
+			dma_cookie_complete(tx);
 			if (tx->callback) {
 				tx->callback(tx->callback_param);
 				tx->callback = NULL;
@@ -398,13 +399,9 @@ static dma_cookie_t ioat2_tx_submit_unlock(struct dma_async_tx_descriptor *tx)
 	struct dma_chan *c = tx->chan;
 	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
 	struct ioat_chan_common *chan = &ioat->base;
-	dma_cookie_t cookie = c->cookie;
+	dma_cookie_t cookie;
 
-	cookie++;
-	if (cookie < 0)
-		cookie = 1;
-	tx->cookie = cookie;
-	c->cookie = cookie;
+	cookie = dma_cookie_assign(tx);
 	dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie);
 
 	if (!test_and_set_bit(IOAT_COMPLETION_PENDING, &chan->state))

drivers/dma/ioat/dma_v3.c

@@ -61,6 +61,7 @@
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/prefetch.h>
+#include "../dmaengine.h"
 #include "registers.h"
 #include "hw.h"
 #include "dma.h"
@@ -277,9 +278,8 @@ static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete)
 		dump_desc_dbg(ioat, desc);
 		tx = &desc->txd;
 		if (tx->cookie) {
-			chan->completed_cookie = tx->cookie;
+			dma_cookie_complete(tx);
 			ioat3_dma_unmap(ioat, desc, idx + i);
-			tx->cookie = 0;
 			if (tx->callback) {
 				tx->callback(tx->callback_param);
 				tx->callback = NULL;
@@ -411,13 +411,15 @@ ioat3_tx_status(struct dma_chan *c, dma_cookie_t cookie,
 		struct dma_tx_state *txstate)
 {
 	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
+	enum dma_status ret;
 
-	if (ioat_tx_status(c, cookie, txstate) == DMA_SUCCESS)
-		return DMA_SUCCESS;
+	ret = dma_cookie_status(c, cookie, txstate);
+	if (ret == DMA_SUCCESS)
+		return ret;
 
 	ioat3_cleanup(ioat);
 
-	return ioat_tx_status(c, cookie, txstate);
+	return dma_cookie_status(c, cookie, txstate);
 }
 
 static struct dma_async_tx_descriptor *

drivers/dma/iop-adma.c

@@ -36,6 +36,8 @@
 
 #include <mach/adma.h>
 
+#include "dmaengine.h"
+
 #define to_iop_adma_chan(chan) container_of(chan, struct iop_adma_chan, common)
 #define to_iop_adma_device(dev) \
 	container_of(dev, struct iop_adma_device, common)
@@ -317,7 +319,7 @@ static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 	}
 
 	if (cookie > 0) {
-		iop_chan->completed_cookie = cookie;
+		iop_chan->common.completed_cookie = cookie;
 		pr_debug("\tcompleted cookie %d\n", cookie);
 	}
 }
@@ -438,18 +440,6 @@ retry:
 	return NULL;
 }
 
-static dma_cookie_t
-iop_desc_assign_cookie(struct iop_adma_chan *iop_chan,
-	struct iop_adma_desc_slot *desc)
-{
-	dma_cookie_t cookie = iop_chan->common.cookie;
-	cookie++;
-	if (cookie < 0)
-		cookie = 1;
-	iop_chan->common.cookie = desc->async_tx.cookie = cookie;
-	return cookie;
-}
-
 static void iop_adma_check_threshold(struct iop_adma_chan *iop_chan)
 {
 	dev_dbg(iop_chan->device->common.dev, "pending: %d\n",
@@ -477,7 +467,7 @@ iop_adma_tx_submit(struct dma_async_tx_descriptor *tx)
 	slots_per_op = grp_start->slots_per_op;
 
 	spin_lock_bh(&iop_chan->lock);
-	cookie = iop_desc_assign_cookie(iop_chan, sw_desc);
+	cookie = dma_cookie_assign(tx);
 
 	old_chain_tail = list_entry(iop_chan->chain.prev,
 		struct iop_adma_desc_slot, chain_node);
@@ -904,24 +894,15 @@ static enum dma_status iop_adma_status(struct dma_chan *chan,
 					struct dma_tx_state *txstate)
 {
 	struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
-	enum dma_status ret;
-
-	last_used = chan->cookie;
-	last_complete = iop_chan->completed_cookie;
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	int ret;
+
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret == DMA_SUCCESS)
 		return ret;
 
 	iop_adma_slot_cleanup(iop_chan);
 
-	last_used = chan->cookie;
-	last_complete = iop_chan->completed_cookie;
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return dma_cookie_status(chan, cookie, txstate);
 }
 
 static irqreturn_t iop_adma_eot_handler(int irq, void *data)
@@ -1565,6 +1546,7 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
 	INIT_LIST_HEAD(&iop_chan->chain);
 	INIT_LIST_HEAD(&iop_chan->all_slots);
 	iop_chan->common.device = dma_dev;
+	dma_cookie_init(&iop_chan->common);
 	list_add_tail(&iop_chan->common.device_node, &dma_dev->channels);
 
 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
@@ -1642,16 +1624,12 @@ static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan)
 		iop_desc_set_dest_addr(grp_start, iop_chan, 0);
 		iop_desc_set_memcpy_src_addr(grp_start, 0);
 
-		cookie = iop_chan->common.cookie;
-		cookie++;
-		if (cookie <= 1)
-			cookie = 2;
+		cookie = dma_cookie_assign(&sw_desc->async_tx);
 
 		/* initialize the completed cookie to be less than
 		 * the most recently used cookie
 		 */
-		iop_chan->completed_cookie = cookie - 1;
-		iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
+		iop_chan->common.completed_cookie = cookie - 1;
 
 		/* channel should not be busy */
 		BUG_ON(iop_chan_is_busy(iop_chan));
@@ -1699,16 +1677,12 @@ static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan)
 		iop_desc_set_xor_src_addr(grp_start, 0, 0);
 		iop_desc_set_xor_src_addr(grp_start, 1, 0);
 
-		cookie = iop_chan->common.cookie;
-		cookie++;
-		if (cookie <= 1)
-			cookie = 2;
+		cookie = dma_cookie_assign(&sw_desc->async_tx);
 
 		/* initialize the completed cookie to be less than
 		 * the most recently used cookie
 		 */
-		iop_chan->completed_cookie = cookie - 1;
-		iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
+		iop_chan->common.completed_cookie = cookie - 1;
 
 		/* channel should not be busy */
 		BUG_ON(iop_chan_is_busy(iop_chan));

drivers/dma/ipu/ipu_idmac.c

@@ -25,6 +25,7 @@
 
 #include <mach/ipu.h>
 
+#include "../dmaengine.h"
 #include "ipu_intern.h"
 
 #define FS_VF_IN_VALID	0x00000002
@@ -866,14 +867,7 @@ static dma_cookie_t idmac_tx_submit(struct dma_async_tx_descriptor *tx)
 
 	dev_dbg(dev, "Submitting sg %p\n", &desc->sg[0]);
 
-	cookie = ichan->dma_chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	/* from dmaengine.h: "last cookie value returned to client" */
-	ichan->dma_chan.cookie = cookie;
-	tx->cookie = cookie;
+	cookie = dma_cookie_assign(tx);
 
 	/* ipu->lock can be taken under ichan->lock, but not v.v. */
 	spin_lock_irqsave(&ichan->lock, flags);
@@ -1295,7 +1289,7 @@ static irqreturn_t idmac_interrupt(int irq, void *dev_id)
 	/* Flip the active buffer - even if update above failed */
 	ichan->active_buffer = !ichan->active_buffer;
 	if (done)
-		ichan->completed = desc->txd.cookie;
+		dma_cookie_complete(&desc->txd);
 
 	callback = desc->txd.callback;
 	callback_param = desc->txd.callback_param;
@@ -1510,8 +1504,7 @@ static int idmac_alloc_chan_resources(struct dma_chan *chan)
 	BUG_ON(chan->client_count > 1);
 	WARN_ON(ichan->status != IPU_CHANNEL_FREE);
 
-	chan->cookie		= 1;
-	ichan->completed	= -ENXIO;
+	dma_cookie_init(chan);
 
 	ret = ipu_irq_map(chan->chan_id);
 	if (ret < 0)
@@ -1600,9 +1593,7 @@ static void idmac_free_chan_resources(struct dma_chan *chan)
 static enum dma_status idmac_tx_status(struct dma_chan *chan,
 		       dma_cookie_t cookie, struct dma_tx_state *txstate)
 {
-	struct idmac_channel *ichan = to_idmac_chan(chan);
-
-	dma_set_tx_state(txstate, ichan->completed, chan->cookie, 0);
+	dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie, 0);
 	if (cookie != chan->cookie)
 		return DMA_ERROR;
 	return DMA_SUCCESS;
@@ -1638,11 +1629,10 @@ static int __init ipu_idmac_init(struct ipu *ipu)
 
 		ichan->status		= IPU_CHANNEL_FREE;
 		ichan->sec_chan_en	= false;
-		ichan->completed	= -ENXIO;
 		snprintf(ichan->eof_name, sizeof(ichan->eof_name), "IDMAC EOF %d", i);
 
 		dma_chan->device	= &idmac->dma;
-		dma_chan->cookie	= 1;
+		dma_cookie_init(dma_chan);
 		dma_chan->chan_id	= i;
 		list_add_tail(&dma_chan->device_node, &dma->channels);
 	}

drivers/dma/mpc512x_dma.c

@@ -44,6 +44,8 @@
 
 #include <linux/random.h>
 
+#include "dmaengine.h"
+
 /* Number of DMA Transfer descriptors allocated per channel */
 #define MPC_DMA_DESCRIPTORS	64
 
@@ -188,7 +190,6 @@ struct mpc_dma_chan {
 	struct list_head		completed;
 	struct mpc_dma_tcd		*tcd;
 	dma_addr_t			tcd_paddr;
-	dma_cookie_t			completed_cookie;
 
 	/* Lock for this structure */
 	spinlock_t			lock;
@@ -365,7 +366,7 @@ static void mpc_dma_process_completed(struct mpc_dma *mdma)
 		/* Free descriptors */
 		spin_lock_irqsave(&mchan->lock, flags);
 		list_splice_tail_init(&list, &mchan->free);
-		mchan->completed_cookie = last_cookie;
+		mchan->chan.completed_cookie = last_cookie;
 		spin_unlock_irqrestore(&mchan->lock, flags);
 	}
 }
@@ -438,13 +439,7 @@ static dma_cookie_t mpc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
 		mpc_dma_execute(mchan);
 
 	/* Update cookie */
-	cookie = mchan->chan.cookie + 1;
-	if (cookie <= 0)
-		cookie = 1;
-
-	mchan->chan.cookie = cookie;
-	mdesc->desc.cookie = cookie;
-
+	cookie = dma_cookie_assign(txd);
 	spin_unlock_irqrestore(&mchan->lock, flags);
 
 	return cookie;
@@ -562,17 +557,14 @@ mpc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 	       struct dma_tx_state *txstate)
 {
 	struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan);
+	enum dma_status ret;
 	unsigned long flags;
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
 
 	spin_lock_irqsave(&mchan->lock, flags);
-	last_used = mchan->chan.cookie;
-	last_complete = mchan->completed_cookie;
+	ret = dma_cookie_status(chan, cookie, txstate);
 	spin_unlock_irqrestore(&mchan->lock, flags);
 
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return ret;
 }
 
 /* Prepare descriptor for memory to memory copy */
@@ -741,8 +733,7 @@ static int __devinit mpc_dma_probe(struct platform_device *op)
 		mchan = &mdma->channels[i];
 
 		mchan->chan.device = dma;
-		mchan->chan.cookie = 1;
-		mchan->completed_cookie = mchan->chan.cookie;
+		dma_cookie_init(&mchan->chan);
 
 		INIT_LIST_HEAD(&mchan->free);
 		INIT_LIST_HEAD(&mchan->prepared);

drivers/dma/mv_xor.c

@@ -26,6 +26,8 @@
 #include <linux/platform_device.h>
 #include <linux/memory.h>
 #include <plat/mv_xor.h>
+
+#include "dmaengine.h"
 #include "mv_xor.h"
 
 static void mv_xor_issue_pending(struct dma_chan *chan);
@@ -435,7 +437,7 @@ static void __mv_xor_slot_cleanup(struct mv_xor_chan *mv_chan)
 	}
 
 	if (cookie > 0)
-		mv_chan->completed_cookie = cookie;
+		mv_chan->common.completed_cookie = cookie;
 }
 
 static void
@@ -534,18 +536,6 @@ retry:
 	return NULL;
 }
 
-static dma_cookie_t
-mv_desc_assign_cookie(struct mv_xor_chan *mv_chan,
-		      struct mv_xor_desc_slot *desc)
-{
-	dma_cookie_t cookie = mv_chan->common.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-	mv_chan->common.cookie = desc->async_tx.cookie = cookie;
-	return cookie;
-}
-
 /************************ DMA engine API functions ****************************/
 static dma_cookie_t
 mv_xor_tx_submit(struct dma_async_tx_descriptor *tx)
@@ -563,7 +553,7 @@ mv_xor_tx_submit(struct dma_async_tx_descriptor *tx)
 	grp_start = sw_desc->group_head;
 
 	spin_lock_bh(&mv_chan->lock);
-	cookie = mv_desc_assign_cookie(mv_chan, sw_desc);
+	cookie = dma_cookie_assign(tx);
 
 	if (list_empty(&mv_chan->chain))
 		list_splice_init(&sw_desc->tx_list, &mv_chan->chain);
@@ -820,27 +810,16 @@ static enum dma_status mv_xor_status(struct dma_chan *chan,
 					  struct dma_tx_state *txstate)
 {
 	struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
 	enum dma_status ret;
 
-	last_used = chan->cookie;
-	last_complete = mv_chan->completed_cookie;
-	mv_chan->is_complete_cookie = cookie;
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret == DMA_SUCCESS) {
 		mv_xor_clean_completed_slots(mv_chan);
 		return ret;
 	}
 	mv_xor_slot_cleanup(mv_chan);
 
-	last_used = chan->cookie;
-	last_complete = mv_chan->completed_cookie;
-
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return dma_cookie_status(chan, cookie, txstate);
 }
 
 static void mv_dump_xor_regs(struct mv_xor_chan *chan)
@@ -1214,6 +1193,7 @@ static int __devinit mv_xor_probe(struct platform_device *pdev)
 	INIT_LIST_HEAD(&mv_chan->completed_slots);
 	INIT_LIST_HEAD(&mv_chan->all_slots);
 	mv_chan->common.device = dma_dev;
+	dma_cookie_init(&mv_chan->common);
 
 	list_add_tail(&mv_chan->common.device_node, &dma_dev->channels);
 

drivers/dma/mv_xor.h

@@ -78,7 +78,6 @@ struct mv_xor_device {
 /**
  * struct mv_xor_chan - internal representation of a XOR channel
  * @pending: allows batching of hardware operations
- * @completed_cookie: identifier for the most recently completed operation
  * @lock: serializes enqueue/dequeue operations to the descriptors pool
  * @mmr_base: memory mapped register base
  * @idx: the index of the xor channel
@@ -93,7 +92,6 @@ struct mv_xor_device {
  */
 struct mv_xor_chan {
 	int			pending;
-	dma_cookie_t		completed_cookie;
 	spinlock_t		lock; /* protects the descriptor slot pool */
 	void __iomem		*mmr_base;
 	unsigned int		idx;
@@ -109,7 +107,6 @@ struct mv_xor_chan {
 #ifdef USE_TIMER
 	unsigned long		cleanup_time;
 	u32			current_on_last_cleanup;
-	dma_cookie_t		is_complete_cookie;
 #endif
 };
 

drivers/dma/mxs-dma.c

@@ -28,6 +28,8 @@
 #include <mach/dma.h>
 #include <mach/common.h>
 
+#include "dmaengine.h"
+
 /*
  * NOTE: The term "PIO" throughout the mxs-dma implementation means
  * PIO mode of mxs apbh-dma and apbx-dma.  With this working mode,
@@ -111,7 +113,6 @@ struct mxs_dma_chan {
 	struct mxs_dma_ccw		*ccw;
 	dma_addr_t			ccw_phys;
 	int				desc_count;
-	dma_cookie_t			last_completed;
 	enum dma_status			status;
 	unsigned int			flags;
 #define MXS_DMA_SG_LOOP			(1 << 0)
@@ -193,19 +194,6 @@ static void mxs_dma_resume_chan(struct mxs_dma_chan *mxs_chan)
 	mxs_chan->status = DMA_IN_PROGRESS;
 }
 
-static dma_cookie_t mxs_dma_assign_cookie(struct mxs_dma_chan *mxs_chan)
-{
-	dma_cookie_t cookie = mxs_chan->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	mxs_chan->chan.cookie = cookie;
-	mxs_chan->desc.cookie = cookie;
-
-	return cookie;
-}
-
 static struct mxs_dma_chan *to_mxs_dma_chan(struct dma_chan *chan)
 {
 	return container_of(chan, struct mxs_dma_chan, chan);
@@ -217,7 +205,7 @@ static dma_cookie_t mxs_dma_tx_submit(struct dma_async_tx_descriptor *tx)
 
 	mxs_dma_enable_chan(mxs_chan);
 
-	return mxs_dma_assign_cookie(mxs_chan);
+	return dma_cookie_assign(tx);
 }
 
 static void mxs_dma_tasklet(unsigned long data)
@@ -274,7 +262,7 @@ static irqreturn_t mxs_dma_int_handler(int irq, void *dev_id)
 		stat1 &= ~(1 << channel);
 
 		if (mxs_chan->status == DMA_SUCCESS)
-			mxs_chan->last_completed = mxs_chan->desc.cookie;
+			dma_cookie_complete(&mxs_chan->desc);
 
 		/* schedule tasklet on this channel */
 		tasklet_schedule(&mxs_chan->tasklet);
@@ -538,7 +526,7 @@ static enum dma_status mxs_dma_tx_status(struct dma_chan *chan,
 	dma_cookie_t last_used;
 
 	last_used = chan->cookie;
-	dma_set_tx_state(txstate, mxs_chan->last_completed, last_used, 0);
+	dma_set_tx_state(txstate, chan->completed_cookie, last_used, 0);
 
 	return mxs_chan->status;
 }
@@ -630,6 +618,7 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
 
 		mxs_chan->mxs_dma = mxs_dma;
 		mxs_chan->chan.device = &mxs_dma->dma_device;
+		dma_cookie_init(&mxs_chan->chan);
 
 		tasklet_init(&mxs_chan->tasklet, mxs_dma_tasklet,
 			     (unsigned long) mxs_chan);

drivers/dma/pch_dma.c

@@ -25,6 +25,8 @@
 #include <linux/module.h>
 #include <linux/pch_dma.h>
 
+#include "dmaengine.h"
+
 #define DRV_NAME "pch-dma"
 
 #define DMA_CTL0_DISABLE		0x0
@@ -105,7 +107,6 @@ struct pch_dma_chan {
 
 	spinlock_t		lock;
 
-	dma_cookie_t		completed_cookie;
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;
@@ -416,20 +417,6 @@ static void pdc_advance_work(struct pch_dma_chan *pd_chan)
 	}
 }
 
-static dma_cookie_t pdc_assign_cookie(struct pch_dma_chan *pd_chan,
-				      struct pch_dma_desc *desc)
-{
-	dma_cookie_t cookie = pd_chan->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	pd_chan->chan.cookie = cookie;
-	desc->txd.cookie = cookie;
-
-	return cookie;
-}
-
 static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
 {
 	struct pch_dma_desc *desc = to_pd_desc(txd);
@@ -437,7 +424,7 @@ static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
 	dma_cookie_t cookie;
 
 	spin_lock(&pd_chan->lock);
-	cookie = pdc_assign_cookie(pd_chan, desc);
+	cookie = dma_cookie_assign(txd);
 
 	if (list_empty(&pd_chan->active_list)) {
 		list_add_tail(&desc->desc_node, &pd_chan->active_list);
@@ -544,7 +531,7 @@ static int pd_alloc_chan_resources(struct dma_chan *chan)
 	spin_lock_irq(&pd_chan->lock);
 	list_splice(&tmp_list, &pd_chan->free_list);
 	pd_chan->descs_allocated = i;
-	pd_chan->completed_cookie = chan->cookie = 1;
+	dma_cookie_init(chan);
 	spin_unlock_irq(&pd_chan->lock);
 
 	pdc_enable_irq(chan, 1);
@@ -578,19 +565,12 @@ static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 				    struct dma_tx_state *txstate)
 {
 	struct pch_dma_chan *pd_chan = to_pd_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_completed;
-	int ret;
+	enum dma_status ret;
 
 	spin_lock_irq(&pd_chan->lock);
-	last_completed = pd_chan->completed_cookie;
-	last_used = chan->cookie;
+	ret = dma_cookie_status(chan, cookie, txstate);
 	spin_unlock_irq(&pd_chan->lock);
 
-	ret = dma_async_is_complete(cookie, last_completed, last_used);
-
-	dma_set_tx_state(txstate, last_completed, last_used, 0);
-
 	return ret;
 }
 
@@ -932,7 +912,7 @@ static int __devinit pch_dma_probe(struct pci_dev *pdev,
 		struct pch_dma_chan *pd_chan = &pd->channels[i];
 
 		pd_chan->chan.device = &pd->dma;
-		pd_chan->chan.cookie = 1;
+		dma_cookie_init(&pd_chan->chan);
 
 		pd_chan->membase = &regs->desc[i];
 

drivers/dma/pl330.c

@@ -28,6 +28,7 @@
 #include <linux/scatterlist.h>
 #include <linux/of.h>
 
+#include "dmaengine.h"
 #define PL330_MAX_CHAN		8
 #define PL330_MAX_IRQS		32
 #define PL330_MAX_PERI		32
@@ -285,6 +286,7 @@ static unsigned cmd_line;
 #endif
 
 /* The number of default descriptors */
+
 #define NR_DEFAULT_DESC	16
 
 /* Populated by the PL330 core driver for DMA API driver's info */
@@ -545,9 +547,6 @@ struct dma_pl330_chan {
 	/* DMA-Engine Channel */
 	struct dma_chan chan;
 
-	/* Last completed cookie */
-	dma_cookie_t completed;
-
 	/* List of to be xfered descriptors */
 	struct list_head work_list;
 
@@ -2320,7 +2319,7 @@ static void pl330_tasklet(unsigned long data)
 	/* Pick up ripe tomatoes */
 	list_for_each_entry_safe(desc, _dt, &pch->work_list, node)
 		if (desc->status == DONE) {
-			pch->completed = desc->txd.cookie;
+			dma_cookie_complete(&desc->txd);
 			list_move_tail(&desc->node, &list);
 		}
 
@@ -2391,7 +2390,7 @@ static int pl330_alloc_chan_resources(struct dma_chan *chan)
 
 	spin_lock_irqsave(&pch->lock, flags);
 
-	pch->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 	pch->cyclic = false;
 
 	pch->pl330_chid = pl330_request_channel(&pdmac->pif);
@@ -2426,7 +2425,6 @@ static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned
 		/* Mark all desc done */
 		list_for_each_entry_safe(desc, _dt, &pch->work_list , node) {
 			desc->status = DONE;
-			pch->completed = desc->txd.cookie;
 			list_move_tail(&desc->node, &list);
 		}
 
@@ -2482,18 +2480,7 @@ static enum dma_status
 pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 		 struct dma_tx_state *txstate)
 {
-	struct dma_pl330_chan *pch = to_pchan(chan);
-	dma_cookie_t last_done, last_used;
-	int ret;
-
-	last_done = pch->completed;
-	last_used = chan->cookie;
-
-	ret = dma_async_is_complete(cookie, last_done, last_used);
-
-	dma_set_tx_state(txstate, last_done, last_used, 0);
-
-	return ret;
+	return dma_cookie_status(chan, cookie, txstate);
 }
 
 static void pl330_issue_pending(struct dma_chan *chan)
@@ -2516,26 +2503,16 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx)
 	spin_lock_irqsave(&pch->lock, flags);
 
 	/* Assign cookies to all nodes */
-	cookie = tx->chan->cookie;
-
 	while (!list_empty(&last->node)) {
 		desc = list_entry(last->node.next, struct dma_pl330_desc, node);
 
-		if (++cookie < 0)
-			cookie = 1;
-		desc->txd.cookie = cookie;
+		dma_cookie_assign(&desc->txd);
 
 		list_move_tail(&desc->node, &pch->work_list);
 	}
 
-	if (++cookie < 0)
-		cookie = 1;
-	last->txd.cookie = cookie;
-
+	cookie = dma_cookie_assign(&last->txd);
 	list_add_tail(&last->node, &pch->work_list);
-
-	tx->chan->cookie = cookie;
-
 	spin_unlock_irqrestore(&pch->lock, flags);
 
 	return cookie;

drivers/dma/ppc4xx/adma.c

@@ -46,6 +46,7 @@
 #include <asm/dcr.h>
 #include <asm/dcr-regs.h>
 #include "adma.h"
+#include "../dmaengine.h"
 
 enum ppc_adma_init_code {
 	PPC_ADMA_INIT_OK = 0,
@@ -1930,7 +1931,7 @@ static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
 				if (end_of_chain && slot_cnt) {
 					/* Should wait for ZeroSum completion */
 					if (cookie > 0)
-						chan->completed_cookie = cookie;
+						chan->common.completed_cookie = cookie;
 					return;
 				}
 
@@ -1960,7 +1961,7 @@ static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
 	BUG_ON(!seen_current);
 
 	if (cookie > 0) {
-		chan->completed_cookie = cookie;
+		chan->common.completed_cookie = cookie;
 		pr_debug("\tcompleted cookie %d\n", cookie);
 	}
 
@@ -2149,22 +2150,6 @@ static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
 	return (i > 0) ? i : -ENOMEM;
 }
 
-/**
- * ppc440spe_desc_assign_cookie - assign a cookie
- */
-static dma_cookie_t ppc440spe_desc_assign_cookie(
-		struct ppc440spe_adma_chan *chan,
-		struct ppc440spe_adma_desc_slot *desc)
-{
-	dma_cookie_t cookie = chan->common.cookie;
-
-	cookie++;
-	if (cookie < 0)
-		cookie = 1;
-	chan->common.cookie = desc->async_tx.cookie = cookie;
-	return cookie;
-}
-
 /**
  * ppc440spe_rxor_set_region_data -
  */
@@ -2235,8 +2220,7 @@ static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
 	slots_per_op = group_start->slots_per_op;
 
 	spin_lock_bh(&chan->lock);
-
-	cookie = ppc440spe_desc_assign_cookie(chan, sw_desc);
+	cookie = dma_cookie_assign(tx);
 
 	if (unlikely(list_empty(&chan->chain))) {
 		/* first peer */
@@ -3944,28 +3928,16 @@ static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
 			dma_cookie_t cookie, struct dma_tx_state *txstate)
 {
 	struct ppc440spe_adma_chan *ppc440spe_chan;
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
 	enum dma_status ret;
 
 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
-	last_used = chan->cookie;
-	last_complete = ppc440spe_chan->completed_cookie;
-
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret == DMA_SUCCESS)
 		return ret;
 
 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
 
-	last_used = chan->cookie;
-	last_complete = ppc440spe_chan->completed_cookie;
-
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return dma_cookie_status(chan, cookie, txstate);
 }
 
 /**
@@ -4050,16 +4022,12 @@ static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
 		async_tx_ack(&sw_desc->async_tx);
 		ppc440spe_desc_init_null_xor(group_start);
 
-		cookie = chan->common.cookie;
-		cookie++;
-		if (cookie <= 1)
-			cookie = 2;
+		cookie = dma_cookie_assign(&sw_desc->async_tx);
 
 		/* initialize the completed cookie to be less than
 		 * the most recently used cookie
 		 */
-		chan->completed_cookie = cookie - 1;
-		chan->common.cookie = sw_desc->async_tx.cookie = cookie;
+		chan->common.completed_cookie = cookie - 1;
 
 		/* channel should not be busy */
 		BUG_ON(ppc440spe_chan_is_busy(chan));
@@ -4529,6 +4497,7 @@ static int __devinit ppc440spe_adma_probe(struct platform_device *ofdev)
 	INIT_LIST_HEAD(&chan->all_slots);
 	chan->device = adev;
 	chan->common.device = &adev->common;
+	dma_cookie_init(&chan->common);
 	list_add_tail(&chan->common.device_node, &adev->common.channels);
 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
 		     (unsigned long)chan);

drivers/dma/ppc4xx/adma.h

@@ -81,7 +81,6 @@ struct ppc440spe_adma_device {
  * @common: common dmaengine channel object members
  * @all_slots: complete domain of slots usable by the channel
  * @pending: allows batching of hardware operations
- * @completed_cookie: identifier for the most recently completed operation
  * @slots_allocated: records the actual size of the descriptor slot pool
  * @hw_chain_inited: h/w descriptor chain initialization flag
  * @irq_tasklet: bottom half where ppc440spe_adma_slot_cleanup runs
@@ -99,7 +98,6 @@ struct ppc440spe_adma_chan {
 	struct list_head all_slots;
 	struct ppc440spe_adma_desc_slot *last_used;
 	int pending;
-	dma_cookie_t completed_cookie;
 	int slots_allocated;
 	int hw_chain_inited;
 	struct tasklet_struct irq_tasklet;

drivers/dma/shdma.c

@@ -30,6 +30,8 @@
 #include <linux/kdebug.h>
 #include <linux/spinlock.h>
 #include <linux/rculist.h>
+
+#include "dmaengine.h"
 #include "shdma.h"
 
 /* DMA descriptor control */
@@ -296,13 +298,7 @@ static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
 	else
 		power_up = false;
 
-	cookie = sh_chan->common.cookie;
-	cookie++;
-	if (cookie < 0)
-		cookie = 1;
-
-	sh_chan->common.cookie = cookie;
-	tx->cookie = cookie;
+	cookie = dma_cookie_assign(tx);
 
 	/* Mark all chunks of this descriptor as submitted, move to the queue */
 	list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
@@ -764,12 +760,12 @@ static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all
 			cookie = tx->cookie;
 
 		if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
-			if (sh_chan->completed_cookie != desc->cookie - 1)
+			if (sh_chan->common.completed_cookie != desc->cookie - 1)
 				dev_dbg(sh_chan->dev,
 					"Completing cookie %d, expected %d\n",
 					desc->cookie,
-					sh_chan->completed_cookie + 1);
-			sh_chan->completed_cookie = desc->cookie;
+					sh_chan->common.completed_cookie + 1);
+			sh_chan->common.completed_cookie = desc->cookie;
 		}
 
 		/* Call callback on the last chunk */
@@ -823,7 +819,7 @@ static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all
 		 * Terminating and the loop completed normally: forgive
 		 * uncompleted cookies
 		 */
-		sh_chan->completed_cookie = sh_chan->common.cookie;
+		sh_chan->common.completed_cookie = sh_chan->common.cookie;
 
 	spin_unlock_irqrestore(&sh_chan->desc_lock, flags);
 
@@ -883,23 +879,14 @@ static enum dma_status sh_dmae_tx_status(struct dma_chan *chan,
 					struct dma_tx_state *txstate)
 {
 	struct sh_dmae_chan *sh_chan = to_sh_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
 	enum dma_status status;
 	unsigned long flags;
 
 	sh_dmae_chan_ld_cleanup(sh_chan, false);
 
-	/* First read completed cookie to avoid a skew */
-	last_complete = sh_chan->completed_cookie;
-	rmb();
-	last_used = chan->cookie;
-	BUG_ON(last_complete < 0);
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
 	spin_lock_irqsave(&sh_chan->desc_lock, flags);
 
-	status = dma_async_is_complete(cookie, last_complete, last_used);
+	status = dma_cookie_status(chan, cookie, txstate);
 
 	/*
 	 * If we don't find cookie on the queue, it has been aborted and we have
@@ -1102,6 +1089,7 @@ static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id,
 
 	/* reference struct dma_device */
 	new_sh_chan->common.device = &shdev->common;
+	dma_cookie_init(&new_sh_chan->common);
 
 	new_sh_chan->dev = shdev->common.dev;
 	new_sh_chan->id = id;

drivers/dma/shdma.h

@@ -30,7 +30,6 @@ enum dmae_pm_state {
 };
 
 struct sh_dmae_chan {
-	dma_cookie_t completed_cookie;	/* The maximum cookie completed */
 	spinlock_t desc_lock;		/* Descriptor operation lock */
 	struct list_head ld_queue;	/* Link descriptors queue */
 	struct list_head ld_free;	/* Link descriptors free */

drivers/dma/sirf-dma.c

@@ -18,6 +18,8 @@
 #include <linux/of_platform.h>
 #include <linux/sirfsoc_dma.h>
 
+#include "dmaengine.h"
+
 #define SIRFSOC_DMA_DESCRIPTORS                 16
 #define SIRFSOC_DMA_CHANNELS                    16
 
@@ -59,7 +61,6 @@ struct sirfsoc_dma_chan {
 	struct list_head		queued;
 	struct list_head		active;
 	struct list_head		completed;
-	dma_cookie_t			completed_cookie;
 	unsigned long			happened_cyclic;
 	unsigned long			completed_cyclic;
 
@@ -208,7 +209,7 @@ static void sirfsoc_dma_process_completed(struct sirfsoc_dma *sdma)
 			/* Free descriptors */
 			spin_lock_irqsave(&schan->lock, flags);
 			list_splice_tail_init(&list, &schan->free);
-			schan->completed_cookie = last_cookie;
+			schan->chan.completed_cookie = last_cookie;
 			spin_unlock_irqrestore(&schan->lock, flags);
 		} else {
 			/* for cyclic channel, desc is always in active list */
@@ -258,13 +259,7 @@ static dma_cookie_t sirfsoc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
 	/* Move descriptor to queue */
 	list_move_tail(&sdesc->node, &schan->queued);
 
-	/* Update cookie */
-	cookie = schan->chan.cookie + 1;
-	if (cookie <= 0)
-		cookie = 1;
-
-	schan->chan.cookie = cookie;
-	sdesc->desc.cookie = cookie;
+	cookie = dma_cookie_assign(txd);
 
 	spin_unlock_irqrestore(&schan->lock, flags);
 
@@ -414,16 +409,13 @@ sirfsoc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 {
 	struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
 	unsigned long flags;
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
+	enum dma_status ret;
 
 	spin_lock_irqsave(&schan->lock, flags);
-	last_used = schan->chan.cookie;
-	last_complete = schan->completed_cookie;
+	ret = dma_cookie_status(chan, cookie, txstate);
 	spin_unlock_irqrestore(&schan->lock, flags);
 
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-	return dma_async_is_complete(cookie, last_complete, last_used);
+	return ret;
 }
 
 static struct dma_async_tx_descriptor *sirfsoc_dma_prep_interleaved(
@@ -635,8 +627,7 @@ static int __devinit sirfsoc_dma_probe(struct platform_device *op)
 		schan = &sdma->channels[i];
 
 		schan->chan.device = dma;
-		schan->chan.cookie = 1;
-		schan->completed_cookie = schan->chan.cookie;
+		dma_cookie_init(&schan->chan);
 
 		INIT_LIST_HEAD(&schan->free);
 		INIT_LIST_HEAD(&schan->prepared);

drivers/dma/ste_dma40.c

@@ -21,6 +21,7 @@
 
 #include <plat/ste_dma40.h>
 
+#include "dmaengine.h"
 #include "ste_dma40_ll.h"
 
 #define D40_NAME "dma40"
@@ -220,8 +221,6 @@ struct d40_base;
  *
  * @lock: A spinlock to protect this struct.
  * @log_num: The logical number, if any of this channel.
- * @completed: Starts with 1, after first interrupt it is set to dma engine's
- * current cookie.
  * @pending_tx: The number of pending transfers. Used between interrupt handler
  * and tasklet.
  * @busy: Set to true when transfer is ongoing on this channel.
@@ -250,8 +249,6 @@ struct d40_base;
 struct d40_chan {
 	spinlock_t			 lock;
 	int				 log_num;
-	/* ID of the most recent completed transfer */
-	int				 completed;
 	int				 pending_tx;
 	bool				 busy;
 	struct d40_phy_res		*phy_chan;
@@ -1223,21 +1220,14 @@ static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
 					     chan);
 	struct d40_desc *d40d = container_of(tx, struct d40_desc, txd);
 	unsigned long flags;
+	dma_cookie_t cookie;
 
 	spin_lock_irqsave(&d40c->lock, flags);
-
-	d40c->chan.cookie++;
-
-	if (d40c->chan.cookie < 0)
-		d40c->chan.cookie = 1;
-
-	d40d->txd.cookie = d40c->chan.cookie;
-
+	cookie = dma_cookie_assign(tx);
 	d40_desc_queue(d40c, d40d);
-
 	spin_unlock_irqrestore(&d40c->lock, flags);
 
-	return tx->cookie;
+	return cookie;
 }
 
 static int d40_start(struct d40_chan *d40c)
@@ -1357,7 +1347,7 @@ static void dma_tasklet(unsigned long data)
 		goto err;
 
 	if (!d40d->cyclic)
-		d40c->completed = d40d->txd.cookie;
+		dma_cookie_complete(&d40d->txd);
 
 	/*
 	 * If terminating a channel pending_tx is set to zero.
@@ -2182,7 +2172,7 @@ static int d40_alloc_chan_resources(struct dma_chan *chan)
 	bool is_free_phy;
 	spin_lock_irqsave(&d40c->lock, flags);
 
-	d40c->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 
 	/* If no dma configuration is set use default configuration (memcpy) */
 	if (!d40c->configured) {
@@ -2342,25 +2332,19 @@ static enum dma_status d40_tx_status(struct dma_chan *chan,
 				     struct dma_tx_state *txstate)
 {
 	struct d40_chan *d40c = container_of(chan, struct d40_chan, chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
-	int ret;
+	enum dma_status ret;
 
 	if (d40c->phy_chan == NULL) {
 		chan_err(d40c, "Cannot read status of unallocated channel\n");
 		return -EINVAL;
 	}
 
-	last_complete = d40c->completed;
-	last_used = chan->cookie;
+	ret = dma_cookie_status(chan, cookie, txstate);
+	if (ret != DMA_SUCCESS)
+		dma_set_residue(txstate, stedma40_residue(chan));
 
 	if (d40_is_paused(d40c))
 		ret = DMA_PAUSED;
-	else
-		ret = dma_async_is_complete(cookie, last_complete, last_used);
-
-	dma_set_tx_state(txstate, last_complete, last_used,
-			 stedma40_residue(chan));
 
 	return ret;
 }

drivers/dma/timb_dma.c

@@ -31,6 +31,8 @@
 
 #include <linux/timb_dma.h>
 
+#include "dmaengine.h"
+
 #define DRIVER_NAME "timb-dma"
 
 /* Global DMA registers */
@@ -84,7 +86,6 @@ struct timb_dma_chan {
 					especially the lists and descriptors,
 					from races between the tasklet and calls
 					from above */
-	dma_cookie_t		last_completed_cookie;
 	bool			ongoing;
 	struct list_head	active_list;
 	struct list_head	queue;
@@ -284,7 +285,7 @@ static void __td_finish(struct timb_dma_chan *td_chan)
 	else
 		iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DLAR);
 */
-	td_chan->last_completed_cookie = txd->cookie;
+	dma_cookie_complete(txd);
 	td_chan->ongoing = false;
 
 	callback = txd->callback;
@@ -349,12 +350,7 @@ static dma_cookie_t td_tx_submit(struct dma_async_tx_descriptor *txd)
 	dma_cookie_t cookie;
 
 	spin_lock_bh(&td_chan->lock);
-
-	cookie = txd->chan->cookie;
-	if (++cookie < 0)
-		cookie = 1;
-	txd->chan->cookie = cookie;
-	txd->cookie = cookie;
+	cookie = dma_cookie_assign(txd);
 
 	if (list_empty(&td_chan->active_list)) {
 		dev_dbg(chan2dev(txd->chan), "%s: started %u\n", __func__,
@@ -481,8 +477,7 @@ static int td_alloc_chan_resources(struct dma_chan *chan)
 	}
 
 	spin_lock_bh(&td_chan->lock);
-	td_chan->last_completed_cookie = 1;
-	chan->cookie = 1;
+	dma_cookie_init(chan);
 	spin_unlock_bh(&td_chan->lock);
 
 	return 0;
@@ -515,24 +510,13 @@ static void td_free_chan_resources(struct dma_chan *chan)
 static enum dma_status td_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 				    struct dma_tx_state *txstate)
 {
-	struct timb_dma_chan *td_chan =
-		container_of(chan, struct timb_dma_chan, chan);
-	dma_cookie_t		last_used;
-	dma_cookie_t		last_complete;
-	int			ret;
+	enum dma_status ret;
 
 	dev_dbg(chan2dev(chan), "%s: Entry\n", __func__);
 
-	last_complete = td_chan->last_completed_cookie;
-	last_used = chan->cookie;
-
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
-
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
+	ret = dma_cookie_status(chan, cookie, txstate);
 
-	dev_dbg(chan2dev(chan),
-		"%s: exit, ret: %d, last_complete: %d, last_used: %d\n",
-		__func__, ret, last_complete, last_used);
+	dev_dbg(chan2dev(chan), "%s: exit, ret: %d\n", 	__func__, ret);
 
 	return ret;
 }
@@ -766,7 +750,7 @@ static int __devinit td_probe(struct platform_device *pdev)
 		}
 
 		td_chan->chan.device = &td->dma;
-		td_chan->chan.cookie = 1;
+		dma_cookie_init(&td_chan->chan);
 		spin_lock_init(&td_chan->lock);
 		INIT_LIST_HEAD(&td_chan->active_list);
 		INIT_LIST_HEAD(&td_chan->queue);

drivers/dma/txx9dmac.c

@@ -15,6 +15,8 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/scatterlist.h>
+
+#include "dmaengine.h"
 #include "txx9dmac.h"
 
 static struct txx9dmac_chan *to_txx9dmac_chan(struct dma_chan *chan)
@@ -279,21 +281,6 @@ static void txx9dmac_desc_put(struct txx9dmac_chan *dc,
 	}
 }
 
-/* Called with dc->lock held and bh disabled */
-static dma_cookie_t
-txx9dmac_assign_cookie(struct txx9dmac_chan *dc, struct txx9dmac_desc *desc)
-{
-	dma_cookie_t cookie = dc->chan.cookie;
-
-	if (++cookie < 0)
-		cookie = 1;
-
-	dc->chan.cookie = cookie;
-	desc->txd.cookie = cookie;
-
-	return cookie;
-}
-
 /*----------------------------------------------------------------------*/
 
 static void txx9dmac_dump_regs(struct txx9dmac_chan *dc)
@@ -424,7 +411,7 @@ txx9dmac_descriptor_complete(struct txx9dmac_chan *dc,
 	dev_vdbg(chan2dev(&dc->chan), "descriptor %u %p complete\n",
 		 txd->cookie, desc);
 
-	dc->completed = txd->cookie;
+	dma_cookie_complete(txd);
 	callback = txd->callback;
 	param = txd->callback_param;
 
@@ -738,7 +725,7 @@ static dma_cookie_t txx9dmac_tx_submit(struct dma_async_tx_descriptor *tx)
 	dma_cookie_t cookie;
 
 	spin_lock_bh(&dc->lock);
-	cookie = txx9dmac_assign_cookie(dc, desc);
+	cookie = dma_cookie_assign(tx);
 
 	dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u %p\n",
 		 desc->txd.cookie, desc);
@@ -972,27 +959,17 @@ txx9dmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 		   struct dma_tx_state *txstate)
 {
 	struct txx9dmac_chan *dc = to_txx9dmac_chan(chan);
-	dma_cookie_t last_used;
-	dma_cookie_t last_complete;
-	int ret;
+	enum dma_status ret;
 
-	last_complete = dc->completed;
-	last_used = chan->cookie;
-
-	ret = dma_async_is_complete(cookie, last_complete, last_used);
+	ret = dma_cookie_status(chan, cookie, txstate);
 	if (ret != DMA_SUCCESS) {
 		spin_lock_bh(&dc->lock);
 		txx9dmac_scan_descriptors(dc);
 		spin_unlock_bh(&dc->lock);
 
-		last_complete = dc->completed;
-		last_used = chan->cookie;
-
-		ret = dma_async_is_complete(cookie, last_complete, last_used);
+		ret = dma_cookie_status(chan, cookie, txstate);
 	}
 
-	dma_set_tx_state(txstate, last_complete, last_used, 0);
-
 	return ret;
 }
 
@@ -1057,7 +1034,7 @@ static int txx9dmac_alloc_chan_resources(struct dma_chan *chan)
 		return -EIO;
 	}
 
-	dc->completed = chan->cookie = 1;
+	dma_cookie_init(chan);
 
 	dc->ccr = TXX9_DMA_CCR_IMMCHN | TXX9_DMA_CCR_INTENE | CCR_LE;
 	txx9dmac_chan_set_SMPCHN(dc);
@@ -1186,7 +1163,7 @@ static int __init txx9dmac_chan_probe(struct platform_device *pdev)
 	dc->ddev->chan[ch] = dc;
 	dc->chan.device = &dc->dma;
 	list_add_tail(&dc->chan.device_node, &dc->chan.device->channels);
-	dc->chan.cookie = dc->completed = 1;
+	dma_cookie_init(&dc->chan);
 
 	if (is_dmac64(dc))
 		dc->ch_regs = &__txx9dmac_regs(dc->ddev)->CHAN[ch];

drivers/dma/txx9dmac.h

@@ -172,7 +172,6 @@ struct txx9dmac_chan {
 	spinlock_t		lock;
 
 	/* these other elements are all protected by lock */
-	dma_cookie_t		completed;
 	struct list_head	active_list;
 	struct list_head	queue;
 	struct list_head	free_list;

include/linux/amba/pl08x.h

@@ -172,7 +172,6 @@ enum pl08x_dma_chan_state {
  * @runtime_addr: address for RX/TX according to the runtime config
  * @runtime_direction: current direction of this channel according to
  * runtime config
- * @lc: last completed transaction on this channel
  * @pend_list: queued transactions pending on this channel
  * @at: active transaction on this channel
  * @lock: a lock for this channel data
@@ -197,7 +196,6 @@ struct pl08x_dma_chan {
 	u32 src_cctl;
 	u32 dst_cctl;
 	enum dma_transfer_direction runtime_direction;
-	dma_cookie_t lc;
 	struct list_head pend_list;
 	struct pl08x_txd *at;
 	spinlock_t lock;

include/linux/dmaengine.h

@@ -18,8 +18,8 @@
  * The full GNU General Public License is included in this distribution in the
  * file called COPYING.
  */
-#ifndef DMAENGINE_H
-#define DMAENGINE_H
+#ifndef LINUX_DMAENGINE_H
+#define LINUX_DMAENGINE_H
 
 #include <linux/device.h>
 #include <linux/uio.h>
@@ -258,6 +258,7 @@ struct dma_chan_percpu {
  * struct dma_chan - devices supply DMA channels, clients use them
  * @device: ptr to the dma device who supplies this channel, always !%NULL
  * @cookie: last cookie value returned to client
+ * @completed_cookie: last completed cookie for this channel
  * @chan_id: channel ID for sysfs
  * @dev: class device for sysfs
  * @device_node: used to add this to the device chan list
@@ -269,6 +270,7 @@ struct dma_chan_percpu {
 struct dma_chan {
 	struct dma_device *device;
 	dma_cookie_t cookie;
+	dma_cookie_t completed_cookie;
 
 	/* sysfs */
 	int chan_id;