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 9b1ea0ef59af..a016490c95ae 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 c6adb925f0b9..cb626c179911 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 d5d30ed863ce..24bfaf0b92ba 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 e27cec25c59e..a8d7809e2f4c 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 9e84d5bc9307..3b55bb8d969a 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 4e3549a16132..940c1502a8b5 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 e982f00a9843..d63f68b1aa35 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 8d1058085eeb..695483e6be32 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 b9b38a1cf92f..895f869d6c2c 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 bb48a57c2fc1..000000000000
--- 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 394cbc5c93e3..7938272f2edf 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);