linux-stable/crypto/async_tx/async_memcpy.c
Thomas Gleixner a61127c213 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 51 franklin st fifth floor boston ma 02110
  1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 111 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.567572064@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00

97 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* copy offload engine support
*
* Copyright © 2006, Intel Corporation.
*
* Dan Williams <dan.j.williams@intel.com>
*
* with architecture considerations by:
* Neil Brown <neilb@suse.de>
* Jeff Garzik <jeff@garzik.org>
*/
#include <linux/kernel.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/async_tx.h>
/**
* async_memcpy - attempt to copy memory with a dma engine.
* @dest: destination page
* @src: src page
* @dest_offset: offset into 'dest' to start transaction
* @src_offset: offset into 'src' to start transaction
* @len: length in bytes
* @submit: submission / completion modifiers
*
* honored flags: ASYNC_TX_ACK
*/
struct dma_async_tx_descriptor *
async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
unsigned int src_offset, size_t len,
struct async_submit_ctl *submit)
{
struct dma_chan *chan = async_tx_find_channel(submit, DMA_MEMCPY,
&dest, 1, &src, 1, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx = NULL;
struct dmaengine_unmap_data *unmap = NULL;
if (device)
unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT);
if (unmap && is_dma_copy_aligned(device, src_offset, dest_offset, len)) {
unsigned long dma_prep_flags = 0;
if (submit->cb_fn)
dma_prep_flags |= DMA_PREP_INTERRUPT;
if (submit->flags & ASYNC_TX_FENCE)
dma_prep_flags |= DMA_PREP_FENCE;
unmap->to_cnt = 1;
unmap->addr[0] = dma_map_page(device->dev, src, src_offset, len,
DMA_TO_DEVICE);
unmap->from_cnt = 1;
unmap->addr[1] = dma_map_page(device->dev, dest, dest_offset, len,
DMA_FROM_DEVICE);
unmap->len = len;
tx = device->device_prep_dma_memcpy(chan, unmap->addr[1],
unmap->addr[0], len,
dma_prep_flags);
}
if (tx) {
pr_debug("%s: (async) len: %zu\n", __func__, len);
dma_set_unmap(tx, unmap);
async_tx_submit(chan, tx, submit);
} else {
void *dest_buf, *src_buf;
pr_debug("%s: (sync) len: %zu\n", __func__, len);
/* wait for any prerequisite operations */
async_tx_quiesce(&submit->depend_tx);
dest_buf = kmap_atomic(dest) + dest_offset;
src_buf = kmap_atomic(src) + src_offset;
memcpy(dest_buf, src_buf, len);
kunmap_atomic(src_buf);
kunmap_atomic(dest_buf);
async_tx_sync_epilog(submit);
}
dmaengine_unmap_put(unmap);
return tx;
}
EXPORT_SYMBOL_GPL(async_memcpy);
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("asynchronous memcpy api");
MODULE_LICENSE("GPL");