Merge tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

Pull dmaengine updates from Dan Williams:
 "Even though this has fixes marked for -stable, given the size and the
  needed conflict resolutions this is 3.18-rc1/merge-window material.

  These patches have been languishing in my tree for a long while.  The
  fact that I do not have the time to do proper/prompt maintenance of
  this tree is a primary factor in the decision to step down as
  dmaengine maintainer.  That and the fact that the bulk of drivers/dma/
  activity is going through Vinod these days.

  The net_dma removal has not been in -next.  It has developed simple
  conflicts against mainline and net-next (for-3.18).

  Continuing thanks to Vinod for staying on top of drivers/dma/.

  Summary:

   1/ Step down as dmaengine maintainer see commit 08223d80df38
      "dmaengine maintainer update"

   2/ Removal of net_dma, as it has been marked 'broken' since 3.13
      (commit 77873803363c "net_dma: mark broken"), without reports of
      performance regression.

   3/ Miscellaneous fixes"

* tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  net: make tcp_cleanup_rbuf private
  net_dma: revert 'copied_early'
  net_dma: simple removal
  dmaengine maintainer update
  dmatest: prevent memory leakage on error path in thread
  ioat: Use time_before_jiffies()
  dmaengine: fix xor sources continuation
  dma: mv_xor: Rename __mv_xor_slot_cleanup() to mv_xor_slot_cleanup()
  dma: mv_xor: Remove all callers of mv_xor_slot_cleanup()
  dma: mv_xor: Remove unneeded mv_xor_clean_completed_slots() call
  ioat: Use pci_enable_msix_exact() instead of pci_enable_msix()
  drivers: dma: Include appropriate header file in dca.c
  drivers: dma: Mark functions as static in dma_v3.c
  dma: mv_xor: Add DMA API error checks
  ioat/dca: Use dev_is_pci() to check whether it is pci device

11 files changed, 78 insertions, 437 deletions

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 9b1ea0ef59a..a016490c95a 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -427,18 +427,6 @@ config DMA_OF
 comment "DMA Clients"
 	depends on DMA_ENGINE
 
-config NET_DMA
-	bool "Network: TCP receive copy offload"
-	depends on DMA_ENGINE && NET
-	default (INTEL_IOATDMA || FSL_DMA)
-	depends on BROKEN
-	help
-	  This enables the use of DMA engines in the network stack to
-	  offload receive copy-to-user operations, freeing CPU cycles.
-
-	  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
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index c6adb925f0b..cb626c17991 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -6,7 +6,6 @@ obj-$(CONFIG_DMA_VIRTUAL_CHANNELS) += virt-dma.o
 obj-$(CONFIG_DMA_ACPI) += acpi-dma.o
 obj-$(CONFIG_DMA_OF) += of-dma.o
 
-obj-$(CONFIG_NET_DMA) += iovlock.o
 obj-$(CONFIG_INTEL_MID_DMAC) += intel_mid_dma.o
 obj-$(CONFIG_DMATEST) += dmatest.o
 obj-$(CONFIG_INTEL_IOATDMA) += ioat/
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index d5d30ed863c..24bfaf0b92b 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -1081,110 +1081,6 @@ dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
 }
 EXPORT_SYMBOL(dmaengine_get_unmap_data);
 
-/**
- * dma_async_memcpy_pg_to_pg - offloaded copy from page to page
- * @chan: DMA channel to offload copy to
- * @dest_pg: destination page
- * @dest_off: offset in page to copy to
- * @src_pg: source page
- * @src_off: offset in page to copy from
- * @len: length
- *
- * Both @dest_page/@dest_off and @src_page/@src_off must be mappable to a bus
- * address according to the DMA mapping API rules for streaming mappings.
- * Both @dest_page/@dest_off and @src_page/@src_off must stay memory resident
- * (kernel memory or locked user space pages).
- */
-dma_cookie_t
-dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg,
-	unsigned int dest_off, struct page *src_pg, unsigned int src_off,
-	size_t len)
-{
-	struct dma_device *dev = chan->device;
-	struct dma_async_tx_descriptor *tx;
-	struct dmaengine_unmap_data *unmap;
-	dma_cookie_t cookie;
-	unsigned long flags;
-
-	unmap = dmaengine_get_unmap_data(dev->dev, 2, GFP_NOWAIT);
-	if (!unmap)
-		return -ENOMEM;
-
-	unmap->to_cnt = 1;
-	unmap->from_cnt = 1;
-	unmap->addr[0] = dma_map_page(dev->dev, src_pg, src_off, len,
-				      DMA_TO_DEVICE);
-	unmap->addr[1] = dma_map_page(dev->dev, dest_pg, dest_off, len,
-				      DMA_FROM_DEVICE);
-	unmap->len = len;
-	flags = DMA_CTRL_ACK;
-	tx = dev->device_prep_dma_memcpy(chan, unmap->addr[1], unmap->addr[0],
-					 len, flags);
-
-	if (!tx) {
-		dmaengine_unmap_put(unmap);
-		return -ENOMEM;
-	}
-
-	dma_set_unmap(tx, unmap);
-	cookie = tx->tx_submit(tx);
-	dmaengine_unmap_put(unmap);
-
-	preempt_disable();
-	__this_cpu_add(chan->local->bytes_transferred, len);
-	__this_cpu_inc(chan->local->memcpy_count);
-	preempt_enable();
-
-	return cookie;
-}
-EXPORT_SYMBOL(dma_async_memcpy_pg_to_pg);
-
-/**
- * dma_async_memcpy_buf_to_buf - offloaded copy between virtual addresses
- * @chan: DMA channel to offload copy to
- * @dest: destination address (virtual)
- * @src: source address (virtual)
- * @len: length
- *
- * Both @dest and @src must be mappable to a bus address according to the
- * DMA mapping API rules for streaming mappings.
- * Both @dest and @src must stay memory resident (kernel memory or locked
- * user space pages).
- */
-dma_cookie_t
-dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest,
-			    void *src, size_t len)
-{
-	return dma_async_memcpy_pg_to_pg(chan, virt_to_page(dest),
-					 (unsigned long) dest & ~PAGE_MASK,
-					 virt_to_page(src),
-					 (unsigned long) src & ~PAGE_MASK, len);
-}
-EXPORT_SYMBOL(dma_async_memcpy_buf_to_buf);
-
-/**
- * dma_async_memcpy_buf_to_pg - offloaded copy from address to page
- * @chan: DMA channel to offload copy to
- * @page: destination page
- * @offset: offset in page to copy to
- * @kdata: source address (virtual)
- * @len: length
- *
- * Both @page/@offset and @kdata must be mappable to a bus address according
- * to the DMA mapping API rules for streaming mappings.
- * Both @page/@offset and @kdata must stay memory resident (kernel memory or
- * locked user space pages)
- */
-dma_cookie_t
-dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page,
-			   unsigned int offset, void *kdata, size_t len)
-{
-	return dma_async_memcpy_pg_to_pg(chan, page, offset,
-					 virt_to_page(kdata),
-					 (unsigned long) kdata & ~PAGE_MASK, len);
-}
-EXPORT_SYMBOL(dma_async_memcpy_buf_to_pg);
-
 void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
 	struct dma_chan *chan)
 {
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index e27cec25c59..a8d7809e2f4 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -688,14 +688,14 @@ static int dmatest_func(void *data)
 	runtime = ktime_us_delta(ktime_get(), ktime);
 
 	ret = 0;
+err_dstbuf:
 	for (i = 0; thread->dsts[i]; i++)
 		kfree(thread->dsts[i]);
-err_dstbuf:
 	kfree(thread->dsts);
 err_dsts:
+err_srcbuf:
 	for (i = 0; thread->srcs[i]; i++)
 		kfree(thread->srcs[i]);
-err_srcbuf:
 	kfree(thread->srcs);
 err_srcs:
 	kfree(pq_coefs);
diff --git a/drivers/dma/ioat/dca.c b/drivers/dma/ioat/dca.c
index 9e84d5bc930..3b55bb8d969 100644
--- a/drivers/dma/ioat/dca.c
+++ b/drivers/dma/ioat/dca.c
@@ -35,6 +35,7 @@
 
 #include "dma.h"
 #include "registers.h"
+#include "dma_v2.h"
 
 /*
  * Bit 7 of a tag map entry is the "valid" bit, if it is set then bits 0:6
@@ -147,7 +148,7 @@ static int ioat_dca_add_requester(struct dca_provider *dca, struct device *dev)
 	u16 id;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 	id = dcaid_from_pcidev(pdev);
@@ -179,7 +180,7 @@ static int ioat_dca_remove_requester(struct dca_provider *dca,
 	int i;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 
@@ -320,7 +321,7 @@ static int ioat2_dca_add_requester(struct dca_provider *dca, struct device *dev)
 	u16 global_req_table;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 	id = dcaid_from_pcidev(pdev);
@@ -354,7 +355,7 @@ static int ioat2_dca_remove_requester(struct dca_provider *dca,
 	u16 global_req_table;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 
@@ -496,7 +497,7 @@ static int ioat3_dca_add_requester(struct dca_provider *dca, struct device *dev)
 	u16 global_req_table;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 	id = dcaid_from_pcidev(pdev);
@@ -530,7 +531,7 @@ static int ioat3_dca_remove_requester(struct dca_provider *dca,
 	u16 global_req_table;
 
 	/* This implementation only supports PCI-Express */
-	if (dev->bus != &pci_bus_type)
+	if (!dev_is_pci(dev))
 		return -ENODEV;
 	pdev = to_pci_dev(dev);
 
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index 4e3549a1613..940c1502a8b 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -947,7 +947,7 @@ msix:
 	for (i = 0; i < msixcnt; i++)
 		device->msix_entries[i].entry = i;
 
-	err = pci_enable_msix(pdev, device->msix_entries, msixcnt);
+	err = pci_enable_msix_exact(pdev, device->msix_entries, msixcnt);
 	if (err)
 		goto msi;
 
@@ -1222,7 +1222,6 @@ int ioat1_dma_probe(struct ioatdma_device *device, int dca)
 	err = ioat_probe(device);
 	if (err)
 		return err;
-	ioat_set_tcp_copy_break(4096);
 	err = ioat_register(device);
 	if (err)
 		return err;
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index e982f00a984..d63f68b1aa3 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -214,13 +214,6 @@ __dump_desc_dbg(struct ioat_chan_common *chan, struct ioat_dma_descriptor *hw,
 #define dump_desc_dbg(c, d) \
 	({ if (d) __dump_desc_dbg(&c->base, d->hw, &d->txd, desc_id(d)); 0; })
 
-static inline void ioat_set_tcp_copy_break(unsigned long copybreak)
-{
-	#ifdef CONFIG_NET_DMA
-	sysctl_tcp_dma_copybreak = copybreak;
-	#endif
-}
-
 static inline struct ioat_chan_common *
 ioat_chan_by_index(struct ioatdma_device *device, int index)
 {
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c
index 8d1058085ee..695483e6be3 100644
--- a/drivers/dma/ioat/dma_v2.c
+++ b/drivers/dma/ioat/dma_v2.c
@@ -735,7 +735,8 @@ int ioat2_check_space_lock(struct ioat2_dma_chan *ioat, int num_descs)
 	 * called under bh_disabled so we need to trigger the timer
 	 * event directly
 	 */
-	if (jiffies > chan->timer.expires && timer_pending(&chan->timer)) {
+	if (time_is_before_jiffies(chan->timer.expires)
+	    && timer_pending(&chan->timer)) {
 		struct ioatdma_device *device = chan->device;
 
 		mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
@@ -899,7 +900,6 @@ int ioat2_dma_probe(struct ioatdma_device *device, int dca)
 	err = ioat_probe(device);
 	if (err)
 		return err;
-	ioat_set_tcp_copy_break(2048);
 
 	list_for_each_entry(c, &dma->channels, device_node) {
 		chan = to_chan_common(c);
diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c
index b9b38a1cf92..895f869d6c2 100644
--- a/drivers/dma/ioat/dma_v3.c
+++ b/drivers/dma/ioat/dma_v3.c
@@ -740,7 +740,7 @@ ioat3_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
 	return __ioat3_prep_xor_lock(chan, NULL, dest, src, src_cnt, len, flags);
 }
 
-struct dma_async_tx_descriptor *
+static struct dma_async_tx_descriptor *
 ioat3_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
 		    unsigned int src_cnt, size_t len,
 		    enum sum_check_flags *result, unsigned long flags)
@@ -1091,7 +1091,7 @@ ioat3_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
 	}
 }
 
-struct dma_async_tx_descriptor *
+static struct dma_async_tx_descriptor *
 ioat3_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
 		  enum sum_check_flags *pqres, unsigned long flags)
@@ -1133,7 +1133,7 @@ ioat3_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
 				     flags);
 }
 
-struct dma_async_tx_descriptor *
+static struct dma_async_tx_descriptor *
 ioat3_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
 		     unsigned int src_cnt, size_t len,
 		     enum sum_check_flags *result, unsigned long flags)
@@ -1655,7 +1655,6 @@ int ioat3_dma_probe(struct ioatdma_device *device, int dca)
 	err = ioat_probe(device);
 	if (err)
 		return err;
-	ioat_set_tcp_copy_break(262144);
 
 	list_for_each_entry(c, &dma->channels, device_node) {
 		chan = to_chan_common(c);
diff --git a/drivers/dma/iovlock.c b/drivers/dma/iovlock.c
deleted file mode 100644
index bb48a57c2fc..00000000000
--- a/drivers/dma/iovlock.c
+++ /dev/null
@@ -1,280 +0,0 @@
-/*
- * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
- * Portions based on net/core/datagram.c and copyrighted by their authors.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that 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., 59
- * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- *
- * The full GNU General Public License is included in this distribution in the
- * file called COPYING.
- */
-
-/*
- * This code allows the net stack to make use of a DMA engine for
- * skb to iovec copies.
- */
-
-#include <linux/dmaengine.h>
-#include <linux/pagemap.h>
-#include <linux/slab.h>
-#include <net/tcp.h> /* for memcpy_toiovec */
-#include <asm/io.h>
-#include <asm/uaccess.h>
-
-static int num_pages_spanned(struct iovec *iov)
-{
-	return
-	((PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
-	((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT);
-}
-
-/*
- * Pin down all the iovec pages needed for len bytes.
- * Return a struct dma_pinned_list to keep track of pages pinned down.
- *
- * We are allocating a single chunk of memory, and then carving it up into
- * 3 sections, the latter 2 whose size depends on the number of iovecs and the
- * total number of pages, respectively.
- */
-struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len)
-{
-	struct dma_pinned_list *local_list;
-	struct page **pages;
-	int i;
-	int ret;
-	int nr_iovecs = 0;
-	int iovec_len_used = 0;
-	int iovec_pages_used = 0;
-
-	/* don't pin down non-user-based iovecs */
-	if (segment_eq(get_fs(), KERNEL_DS))
-		return NULL;
-
-	/* determine how many iovecs/pages there are, up front */
-	do {
-		iovec_len_used += iov[nr_iovecs].iov_len;
-		iovec_pages_used += num_pages_spanned(&iov[nr_iovecs]);
-		nr_iovecs++;
-	} while (iovec_len_used < len);
-
-	/* single kmalloc for pinned list, page_list[], and the page arrays */
-	local_list = kmalloc(sizeof(*local_list)
-		+ (nr_iovecs * sizeof (struct dma_page_list))
-		+ (iovec_pages_used * sizeof (struct page*)), GFP_KERNEL);
-	if (!local_list)
-		goto out;
-
-	/* list of pages starts right after the page list array */
-	pages = (struct page **) &local_list->page_list[nr_iovecs];
-
-	local_list->nr_iovecs = 0;
-
-	for (i = 0; i < nr_iovecs; i++) {
-		struct dma_page_list *page_list = &local_list->page_list[i];
-
-		len -= iov[i].iov_len;
-
-		if (!access_ok(VERIFY_WRITE, iov[i].iov_base, iov[i].iov_len))
-			goto unpin;
-
-		page_list->nr_pages = num_pages_spanned(&iov[i]);
-		page_list->base_address = iov[i].iov_base;
-
-		page_list->pages = pages;
-		pages += page_list->nr_pages;
-
-		/* pin pages down */
-		down_read(&current->mm->mmap_sem);
-		ret = get_user_pages(
-			current,
-			current->mm,
-			(unsigned long) iov[i].iov_base,
-			page_list->nr_pages,
-			1,	/* write */
-			0,	/* force */
-			page_list->pages,
-			NULL);
-		up_read(&current->mm->mmap_sem);
-
-		if (ret != page_list->nr_pages)
-			goto unpin;
-
-		local_list->nr_iovecs = i + 1;
-	}
-
-	return local_list;
-
-unpin:
-	dma_unpin_iovec_pages(local_list);
-out:
-	return NULL;
-}
-
-void dma_unpin_iovec_pages(struct dma_pinned_list *pinned_list)
-{
-	int i, j;
-
-	if (!pinned_list)
-		return;
-
-	for (i = 0; i < pinned_list->nr_iovecs; i++) {
-		struct dma_page_list *page_list = &pinned_list->page_list[i];
-		for (j = 0; j < page_list->nr_pages; j++) {
-			set_page_dirty_lock(page_list->pages[j]);
-			page_cache_release(page_list->pages[j]);
-		}
-	}
-
-	kfree(pinned_list);
-}
-
-
-/*
- * We have already pinned down the pages we will be using in the iovecs.
- * Each entry in iov array has corresponding entry in pinned_list->page_list.
- * Using array indexing to keep iov[] and page_list[] in sync.
- * Initial elements in iov array's iov->iov_len will be 0 if already copied into
- *   by another call.
- * iov array length remaining guaranteed to be bigger than len.
- */
-dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov,
-	struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len)
-{
-	int iov_byte_offset;
-	int copy;
-	dma_cookie_t dma_cookie = 0;
-	int iovec_idx;
-	int page_idx;
-
-	if (!chan)
-		return memcpy_toiovec(iov, kdata, len);
-
-	iovec_idx = 0;
-	while (iovec_idx < pinned_list->nr_iovecs) {
-		struct dma_page_list *page_list;
-
-		/* skip already used-up iovecs */
-		while (!iov[iovec_idx].iov_len)
-			iovec_idx++;
-
-		page_list = &pinned_list->page_list[iovec_idx];
-
-		iov_byte_offset = ((unsigned long)iov[iovec_idx].iov_base & ~PAGE_MASK);
-		page_idx = (((unsigned long)iov[iovec_idx].iov_base & PAGE_MASK)
-			 - ((unsigned long)page_list->base_address & PAGE_MASK)) >> PAGE_SHIFT;
-
-		/* break up copies to not cross page boundary */
-		while (iov[iovec_idx].iov_len) {
-			copy = min_t(int, PAGE_SIZE - iov_byte_offset, len);
-			copy = min_t(int, copy, iov[iovec_idx].iov_len);
-
-			dma_cookie = dma_async_memcpy_buf_to_pg(chan,
-					page_list->pages[page_idx],
-					iov_byte_offset,
-					kdata,
-					copy);
-			/* poll for a descriptor slot */
-			if (unlikely(dma_cookie < 0)) {
-				dma_async_issue_pending(chan);
-				continue;
-			}
-
-			len -= copy;
-			iov[iovec_idx].iov_len -= copy;
-			iov[iovec_idx].iov_base += copy;
-
-			if (!len)
-				return dma_cookie;
-
-			kdata += copy;
-			iov_byte_offset = 0;
-			page_idx++;
-		}
-		iovec_idx++;
-	}
-
-	/* really bad if we ever run out of iovecs */
-	BUG();
-	return -EFAULT;
-}
-
-dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
-	struct dma_pinned_list *pinned_list, struct page *page,
-	unsigned int offset, size_t len)
-{
-	int iov_byte_offset;
-	int copy;
-	dma_cookie_t dma_cookie = 0;
-	int iovec_idx;
-	int page_idx;
-	int err;
-
-	/* this needs as-yet-unimplemented buf-to-buff, so punt. */
-	/* TODO: use dma for this */
-	if (!chan || !pinned_list) {
-		u8 *vaddr = kmap(page);
-		err = memcpy_toiovec(iov, vaddr + offset, len);
-		kunmap(page);
-		return err;
-	}
-
-	iovec_idx = 0;
-	while (iovec_idx < pinned_list->nr_iovecs) {
-		struct dma_page_list *page_list;
-
-		/* skip already used-up iovecs */
-		while (!iov[iovec_idx].iov_len)
-			iovec_idx++;
-
-		page_list = &pinned_list->page_list[iovec_idx];
-
-		iov_byte_offset = ((unsigned long)iov[iovec_idx].iov_base & ~PAGE_MASK);
-		page_idx = (((unsigned long)iov[iovec_idx].iov_base & PAGE_MASK)
-			 - ((unsigned long)page_list->base_address & PAGE_MASK)) >> PAGE_SHIFT;
-
-		/* break up copies to not cross page boundary */
-		while (iov[iovec_idx].iov_len) {
-			copy = min_t(int, PAGE_SIZE - iov_byte_offset, len);
-			copy = min_t(int, copy, iov[iovec_idx].iov_len);
-
-			dma_cookie = dma_async_memcpy_pg_to_pg(chan,
-					page_list->pages[page_idx],
-					iov_byte_offset,
-					page,
-					offset,
-					copy);
-			/* poll for a descriptor slot */
-			if (unlikely(dma_cookie < 0)) {
-				dma_async_issue_pending(chan);
-				continue;
-			}
-
-			len -= copy;
-			iov[iovec_idx].iov_len -= copy;
-			iov[iovec_idx].iov_base += copy;
-
-			if (!len)
-				return dma_cookie;
-
-			offset += copy;
-			iov_byte_offset = 0;
-			page_idx++;
-		}
-		iovec_idx++;
-	}
-
-	/* really bad if we ever run out of iovecs */
-	BUG();
-	return -EFAULT;
-}
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index 394cbc5c93e..7938272f2ed 100644
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -310,7 +310,8 @@ mv_xor_clean_slot(struct mv_xor_desc_slot *desc,
 	return 0;
 }
 
-static void __mv_xor_slot_cleanup(struct mv_xor_chan *mv_chan)
+/* This function must be called with the mv_xor_chan spinlock held */
+static void mv_xor_slot_cleanup(struct mv_xor_chan *mv_chan)
 {
 	struct mv_xor_desc_slot *iter, *_iter;
 	dma_cookie_t cookie = 0;
@@ -366,18 +367,13 @@ static void __mv_xor_slot_cleanup(struct mv_xor_chan *mv_chan)
 		mv_chan->dmachan.completed_cookie = cookie;
 }
 
-static void
-mv_xor_slot_cleanup(struct mv_xor_chan *mv_chan)
-{
-	spin_lock_bh(&mv_chan->lock);
-	__mv_xor_slot_cleanup(mv_chan);
-	spin_unlock_bh(&mv_chan->lock);
-}
-
 static void mv_xor_tasklet(unsigned long data)
 {
 	struct mv_xor_chan *chan = (struct mv_xor_chan *) data;
+
+	spin_lock_bh(&chan->lock);
 	mv_xor_slot_cleanup(chan);
+	spin_unlock_bh(&chan->lock);
 }
 
 static struct mv_xor_desc_slot *
@@ -656,9 +652,10 @@ static void mv_xor_free_chan_resources(struct dma_chan *chan)
 	struct mv_xor_desc_slot *iter, *_iter;
 	int in_use_descs = 0;
 
+	spin_lock_bh(&mv_chan->lock);
+
 	mv_xor_slot_cleanup(mv_chan);
 
-	spin_lock_bh(&mv_chan->lock);
 	list_for_each_entry_safe(iter, _iter, &mv_chan->chain,
 					chain_node) {
 		in_use_descs++;
@@ -700,11 +697,12 @@ static enum dma_status mv_xor_status(struct dma_chan *chan,
 	enum dma_status ret;
 
 	ret = dma_cookie_status(chan, cookie, txstate);
-	if (ret == DMA_COMPLETE) {
-		mv_xor_clean_completed_slots(mv_chan);
+	if (ret == DMA_COMPLETE)
 		return ret;
-	}
+
+	spin_lock_bh(&mv_chan->lock);
 	mv_xor_slot_cleanup(mv_chan);
+	spin_unlock_bh(&mv_chan->lock);
 
 	return dma_cookie_status(chan, cookie, txstate);
 }
@@ -782,7 +780,7 @@ static void mv_xor_issue_pending(struct dma_chan *chan)
 
 static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
 {
-	int i;
+	int i, ret;
 	void *src, *dest;
 	dma_addr_t src_dma, dest_dma;
 	struct dma_chan *dma_chan;
@@ -819,19 +817,44 @@ static int mv_xor_memcpy_self_test(struct mv_xor_chan *mv_chan)
 
 	src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src), 0,
 				 PAGE_SIZE, DMA_TO_DEVICE);
-	unmap->to_cnt = 1;
 	unmap->addr[0] = src_dma;
 
+	ret = dma_mapping_error(dma_chan->device->dev, src_dma);
+	if (ret) {
+		err = -ENOMEM;
+		goto free_resources;
+	}
+	unmap->to_cnt = 1;
+
 	dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest), 0,
 				  PAGE_SIZE, DMA_FROM_DEVICE);
-	unmap->from_cnt = 1;
 	unmap->addr[1] = dest_dma;
 
+	ret = dma_mapping_error(dma_chan->device->dev, dest_dma);
+	if (ret) {
+		err = -ENOMEM;
+		goto free_resources;
+	}
+	unmap->from_cnt = 1;
 	unmap->len = PAGE_SIZE;
 
 	tx = mv_xor_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
 				    PAGE_SIZE, 0);
+	if (!tx) {
+		dev_err(dma_chan->device->dev,
+			"Self-test cannot prepare operation, disabling\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
+
 	cookie = mv_xor_tx_submit(tx);
+	if (dma_submit_error(cookie)) {
+		dev_err(dma_chan->device->dev,
+			"Self-test submit error, disabling\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
+
 	mv_xor_issue_pending(dma_chan);
 	async_tx_ack(tx);
 	msleep(1);
@@ -866,7 +889,7 @@ out:
 static int
 mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
 {
-	int i, src_idx;
+	int i, src_idx, ret;
 	struct page *dest;
 	struct page *xor_srcs[MV_XOR_NUM_SRC_TEST];
 	dma_addr_t dma_srcs[MV_XOR_NUM_SRC_TEST];
@@ -929,19 +952,42 @@ mv_xor_xor_self_test(struct mv_xor_chan *mv_chan)
 		unmap->addr[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
 					      0, PAGE_SIZE, DMA_TO_DEVICE);
 		dma_srcs[i] = unmap->addr[i];
+		ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[i]);
+		if (ret) {
+			err = -ENOMEM;
+			goto free_resources;
+		}
 		unmap->to_cnt++;
 	}
 
 	unmap->addr[src_count] = dma_map_page(dma_chan->device->dev, dest, 0, PAGE_SIZE,
 				      DMA_FROM_DEVICE);
 	dest_dma = unmap->addr[src_count];
+	ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[src_count]);
+	if (ret) {
+		err = -ENOMEM;
+		goto free_resources;
+	}
 	unmap->from_cnt = 1;
 	unmap->len = PAGE_SIZE;
 
 	tx = mv_xor_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
 				 src_count, PAGE_SIZE, 0);
+	if (!tx) {
+		dev_err(dma_chan->device->dev,
+			"Self-test cannot prepare operation, disabling\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
 
 	cookie = mv_xor_tx_submit(tx);
+	if (dma_submit_error(cookie)) {
+		dev_err(dma_chan->device->dev,
+			"Self-test submit error, disabling\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
+
 	mv_xor_issue_pending(dma_chan);
 	async_tx_ack(tx);
 	msleep(8);