Commit 729b5d1b authored by Dan Williams's avatar Dan Williams
Browse files

dmaengine: allow dma support for async_tx to be toggled 



Provide a config option for blocking the allocation of dma channels to
the async_tx api.

Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 06164f31

crypto/async_tx/async_tx.c

+3 −3
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ 
#ifdef CONFIG_DMA_ENGINE

static int __init async_tx_init(void)

{

	dmaengine_get();

	async_dmaengine_get();



	printk(KERN_INFO "async_tx: api initialized (async)\n");
@@ -39,7 +39,7 @@ static int __init async_tx_init(void) 


static void __exit async_tx_exit(void)

{

	dmaengine_put();

	async_dmaengine_put();

}



/**
@@ -56,7 +56,7 @@ __async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx, 
	if (depend_tx &&

	    dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))

		return depend_tx->chan;

	return dma_find_channel(tx_type);

	return async_dma_find_channel(tx_type);

}

EXPORT_SYMBOL_GPL(__async_tx_find_channel);

#else

drivers/dma/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -98,6 +98,17 @@ config NET_DMA 
	  Say Y here if you enabled INTEL_IOATDMA or FSL_DMA, otherwise

	  say N.



config ASYNC_TX_DMA

	bool "Async_tx: Offload support for the async_tx api"

	depends on DMA_ENGINE

	help

	  This allows the async_tx api to take advantage of offload engines for

	  memcpy, memset, xor, and raid6 p+q operations.  If your platform has

	  a dma engine that can perform raid operations and you have enabled

	  MD_RAID456 say Y.



	  If unsure, say N.



config DMATEST

	tristate "DMA Test client"

	depends on DMA_ENGINE

include/linux/dmaengine.h

+18 −0
Original line number Diff line number Diff line
@@ -288,6 +288,24 @@ static inline void net_dmaengine_put(void) 
}

#endif



#ifdef CONFIG_ASYNC_TX_DMA

#define async_dmaengine_get()	dmaengine_get()

#define async_dmaengine_put()	dmaengine_put()

#define async_dma_find_channel(type) dma_find_channel(type)

#else

static inline void async_dmaengine_get(void)

{

}

static inline void async_dmaengine_put(void)

{

}

static inline struct dma_chan *

async_dma_find_channel(enum dma_transaction_type type)

{

	return NULL;

}

#endif



dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,

	void *dest, void *src, size_t len);

dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,