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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /crypto/async_tx
Initial import
Diffstat (limited to 'crypto/async_tx')
-rw-r--r--crypto/async_tx/Kconfig27
-rw-r--r--crypto/async_tx/Makefile6
-rw-r--r--crypto/async_tx/async_memcpy.c110
-rw-r--r--crypto/async_tx/async_pq.c454
-rw-r--r--crypto/async_tx/async_raid6_recov.c531
-rw-r--r--crypto/async_tx/async_tx.c294
-rw-r--r--crypto/async_tx/async_xor.c345
-rw-r--r--crypto/async_tx/raid6test.c253
8 files changed, 2020 insertions, 0 deletions
diff --git a/crypto/async_tx/Kconfig b/crypto/async_tx/Kconfig
new file mode 100644
index 000000000..f38a58aef
--- /dev/null
+++ b/crypto/async_tx/Kconfig
@@ -0,0 +1,27 @@
+config ASYNC_CORE
+ tristate
+
+config ASYNC_MEMCPY
+ tristate
+ select ASYNC_CORE
+
+config ASYNC_XOR
+ tristate
+ select ASYNC_CORE
+ select XOR_BLOCKS
+
+config ASYNC_PQ
+ tristate
+ select ASYNC_CORE
+
+config ASYNC_RAID6_RECOV
+ tristate
+ select ASYNC_CORE
+ select ASYNC_PQ
+ select ASYNC_XOR
+
+config ASYNC_TX_DISABLE_PQ_VAL_DMA
+ bool
+
+config ASYNC_TX_DISABLE_XOR_VAL_DMA
+ bool
diff --git a/crypto/async_tx/Makefile b/crypto/async_tx/Makefile
new file mode 100644
index 000000000..462e4abbf
--- /dev/null
+++ b/crypto/async_tx/Makefile
@@ -0,0 +1,6 @@
+obj-$(CONFIG_ASYNC_CORE) += async_tx.o
+obj-$(CONFIG_ASYNC_MEMCPY) += async_memcpy.o
+obj-$(CONFIG_ASYNC_XOR) += async_xor.o
+obj-$(CONFIG_ASYNC_PQ) += async_pq.o
+obj-$(CONFIG_ASYNC_RAID6_RECOV) += async_raid6_recov.o
+obj-$(CONFIG_ASYNC_RAID6_TEST) += raid6test.o
diff --git a/crypto/async_tx/async_memcpy.c b/crypto/async_tx/async_memcpy.c
new file mode 100644
index 000000000..f8c0b8dbe
--- /dev/null
+++ b/crypto/async_tx/async_memcpy.c
@@ -0,0 +1,110 @@
+/*
+ * 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>
+ *
+ * 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.
+ *
+ */
+#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_NOIO);
+
+ 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");
diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c
new file mode 100644
index 000000000..5d355e0c2
--- /dev/null
+++ b/crypto/async_tx/async_pq.c
@@ -0,0 +1,454 @@
+/*
+ * Copyright(c) 2007 Yuri Tikhonov <yur@emcraft.com>
+ * Copyright(c) 2009 Intel Corporation
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/dma-mapping.h>
+#include <linux/raid/pq.h>
+#include <linux/async_tx.h>
+#include <linux/gfp.h>
+
+/**
+ * pq_scribble_page - space to hold throwaway P or Q buffer for
+ * synchronous gen_syndrome
+ */
+static struct page *pq_scribble_page;
+
+/* the struct page *blocks[] parameter passed to async_gen_syndrome()
+ * and async_syndrome_val() contains the 'P' destination address at
+ * blocks[disks-2] and the 'Q' destination address at blocks[disks-1]
+ *
+ * note: these are macros as they are used as lvalues
+ */
+#define P(b, d) (b[d-2])
+#define Q(b, d) (b[d-1])
+
+/**
+ * do_async_gen_syndrome - asynchronously calculate P and/or Q
+ */
+static __async_inline struct dma_async_tx_descriptor *
+do_async_gen_syndrome(struct dma_chan *chan,
+ const unsigned char *scfs, int disks,
+ struct dmaengine_unmap_data *unmap,
+ enum dma_ctrl_flags dma_flags,
+ struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct dma_device *dma = chan->device;
+ enum async_tx_flags flags_orig = submit->flags;
+ dma_async_tx_callback cb_fn_orig = submit->cb_fn;
+ dma_async_tx_callback cb_param_orig = submit->cb_param;
+ int src_cnt = disks - 2;
+ unsigned short pq_src_cnt;
+ dma_addr_t dma_dest[2];
+ int src_off = 0;
+
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_flags |= DMA_PREP_FENCE;
+
+ while (src_cnt > 0) {
+ submit->flags = flags_orig;
+ pq_src_cnt = min(src_cnt, dma_maxpq(dma, dma_flags));
+ /* if we are submitting additional pqs, leave the chain open,
+ * clear the callback parameters, and leave the destination
+ * buffers mapped
+ */
+ if (src_cnt > pq_src_cnt) {
+ submit->flags &= ~ASYNC_TX_ACK;
+ submit->flags |= ASYNC_TX_FENCE;
+ submit->cb_fn = NULL;
+ submit->cb_param = NULL;
+ } else {
+ submit->cb_fn = cb_fn_orig;
+ submit->cb_param = cb_param_orig;
+ if (cb_fn_orig)
+ dma_flags |= DMA_PREP_INTERRUPT;
+ }
+
+ /* Drivers force forward progress in case they can not provide
+ * a descriptor
+ */
+ for (;;) {
+ dma_dest[0] = unmap->addr[disks - 2];
+ dma_dest[1] = unmap->addr[disks - 1];
+ tx = dma->device_prep_dma_pq(chan, dma_dest,
+ &unmap->addr[src_off],
+ pq_src_cnt,
+ &scfs[src_off], unmap->len,
+ dma_flags);
+ if (likely(tx))
+ break;
+ async_tx_quiesce(&submit->depend_tx);
+ dma_async_issue_pending(chan);
+ }
+
+ dma_set_unmap(tx, unmap);
+ async_tx_submit(chan, tx, submit);
+ submit->depend_tx = tx;
+
+ /* drop completed sources */
+ src_cnt -= pq_src_cnt;
+ src_off += pq_src_cnt;
+
+ dma_flags |= DMA_PREP_CONTINUE;
+ }
+
+ return tx;
+}
+
+/**
+ * do_sync_gen_syndrome - synchronously calculate a raid6 syndrome
+ */
+static void
+do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
+ size_t len, struct async_submit_ctl *submit)
+{
+ void **srcs;
+ int i;
+ int start = -1, stop = disks - 3;
+
+ if (submit->scribble)
+ srcs = submit->scribble;
+ else
+ srcs = (void **) blocks;
+
+ for (i = 0; i < disks; i++) {
+ if (blocks[i] == NULL) {
+ BUG_ON(i > disks - 3); /* P or Q can't be zero */
+ srcs[i] = (void*)raid6_empty_zero_page;
+ } else {
+ srcs[i] = page_address(blocks[i]) + offset;
+ if (i < disks - 2) {
+ stop = i;
+ if (start == -1)
+ start = i;
+ }
+ }
+ }
+ if (submit->flags & ASYNC_TX_PQ_XOR_DST) {
+ BUG_ON(!raid6_call.xor_syndrome);
+ if (start >= 0)
+ raid6_call.xor_syndrome(disks, start, stop, len, srcs);
+ } else
+ raid6_call.gen_syndrome(disks, len, srcs);
+ async_tx_sync_epilog(submit);
+}
+
+/**
+ * async_gen_syndrome - asynchronously calculate a raid6 syndrome
+ * @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1
+ * @offset: common offset into each block (src and dest) to start transaction
+ * @disks: number of blocks (including missing P or Q, see below)
+ * @len: length of operation in bytes
+ * @submit: submission/completion modifiers
+ *
+ * General note: This routine assumes a field of GF(2^8) with a
+ * primitive polynomial of 0x11d and a generator of {02}.
+ *
+ * 'disks' note: callers can optionally omit either P or Q (but not
+ * both) from the calculation by setting blocks[disks-2] or
+ * blocks[disks-1] to NULL. When P or Q is omitted 'len' must be <=
+ * PAGE_SIZE as a temporary buffer of this size is used in the
+ * synchronous path. 'disks' always accounts for both destination
+ * buffers. If any source buffers (blocks[i] where i < disks - 2) are
+ * set to NULL those buffers will be replaced with the raid6_zero_page
+ * in the synchronous path and omitted in the hardware-asynchronous
+ * path.
+ */
+struct dma_async_tx_descriptor *
+async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
+ size_t len, struct async_submit_ctl *submit)
+{
+ int src_cnt = disks - 2;
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
+ &P(blocks, disks), 2,
+ blocks, src_cnt, len);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dmaengine_unmap_data *unmap = NULL;
+
+ BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks)));
+
+ if (device)
+ unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO);
+
+ /* XORing P/Q is only implemented in software */
+ if (unmap && !(submit->flags & ASYNC_TX_PQ_XOR_DST) &&
+ (src_cnt <= dma_maxpq(device, 0) ||
+ dma_maxpq(device, DMA_PREP_CONTINUE) > 0) &&
+ is_dma_pq_aligned(device, offset, 0, len)) {
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = 0;
+ unsigned char coefs[src_cnt];
+ int i, j;
+
+ /* run the p+q asynchronously */
+ pr_debug("%s: (async) disks: %d len: %zu\n",
+ __func__, disks, len);
+
+ /* convert source addresses being careful to collapse 'empty'
+ * sources and update the coefficients accordingly
+ */
+ unmap->len = len;
+ for (i = 0, j = 0; i < src_cnt; i++) {
+ if (blocks[i] == NULL)
+ continue;
+ unmap->addr[j] = dma_map_page(device->dev, blocks[i], offset,
+ len, DMA_TO_DEVICE);
+ coefs[j] = raid6_gfexp[i];
+ unmap->to_cnt++;
+ j++;
+ }
+
+ /*
+ * DMAs use destinations as sources,
+ * so use BIDIRECTIONAL mapping
+ */
+ unmap->bidi_cnt++;
+ if (P(blocks, disks))
+ unmap->addr[j++] = dma_map_page(device->dev, P(blocks, disks),
+ offset, len, DMA_BIDIRECTIONAL);
+ else {
+ unmap->addr[j++] = 0;
+ dma_flags |= DMA_PREP_PQ_DISABLE_P;
+ }
+
+ unmap->bidi_cnt++;
+ if (Q(blocks, disks))
+ unmap->addr[j++] = dma_map_page(device->dev, Q(blocks, disks),
+ offset, len, DMA_BIDIRECTIONAL);
+ else {
+ unmap->addr[j++] = 0;
+ dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+ }
+
+ tx = do_async_gen_syndrome(chan, coefs, j, unmap, dma_flags, submit);
+ dmaengine_unmap_put(unmap);
+ return tx;
+ }
+
+ dmaengine_unmap_put(unmap);
+
+ /* run the pq synchronously */
+ pr_debug("%s: (sync) disks: %d len: %zu\n", __func__, disks, len);
+
+ /* wait for any prerequisite operations */
+ async_tx_quiesce(&submit->depend_tx);
+
+ if (!P(blocks, disks)) {
+ P(blocks, disks) = pq_scribble_page;
+ BUG_ON(len + offset > PAGE_SIZE);
+ }
+ if (!Q(blocks, disks)) {
+ Q(blocks, disks) = pq_scribble_page;
+ BUG_ON(len + offset > PAGE_SIZE);
+ }
+ do_sync_gen_syndrome(blocks, offset, disks, len, submit);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(async_gen_syndrome);
+
+static inline struct dma_chan *
+pq_val_chan(struct async_submit_ctl *submit, struct page **blocks, int disks, size_t len)
+{
+ #ifdef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+ return NULL;
+ #endif
+ return async_tx_find_channel(submit, DMA_PQ_VAL, NULL, 0, blocks,
+ disks, len);
+}
+
+/**
+ * async_syndrome_val - asynchronously validate a raid6 syndrome
+ * @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1
+ * @offset: common offset into each block (src and dest) to start transaction
+ * @disks: number of blocks (including missing P or Q, see below)
+ * @len: length of operation in bytes
+ * @pqres: on val failure SUM_CHECK_P_RESULT and/or SUM_CHECK_Q_RESULT are set
+ * @spare: temporary result buffer for the synchronous case
+ * @submit: submission / completion modifiers
+ *
+ * The same notes from async_gen_syndrome apply to the 'blocks',
+ * and 'disks' parameters of this routine. The synchronous path
+ * requires a temporary result buffer and submit->scribble to be
+ * specified.
+ */
+struct dma_async_tx_descriptor *
+async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
+ size_t len, enum sum_check_flags *pqres, struct page *spare,
+ struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan = pq_val_chan(submit, blocks, disks, len);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx;
+ unsigned char coefs[disks-2];
+ enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
+ struct dmaengine_unmap_data *unmap = NULL;
+
+ BUG_ON(disks < 4);
+
+ if (device)
+ unmap = dmaengine_get_unmap_data(device->dev, disks, GFP_NOIO);
+
+ if (unmap && disks <= dma_maxpq(device, 0) &&
+ is_dma_pq_aligned(device, offset, 0, len)) {
+ struct device *dev = device->dev;
+ dma_addr_t pq[2];
+ int i, j = 0, src_cnt = 0;
+
+ pr_debug("%s: (async) disks: %d len: %zu\n",
+ __func__, disks, len);
+
+ unmap->len = len;
+ for (i = 0; i < disks-2; i++)
+ if (likely(blocks[i])) {
+ unmap->addr[j] = dma_map_page(dev, blocks[i],
+ offset, len,
+ DMA_TO_DEVICE);
+ coefs[j] = raid6_gfexp[i];
+ unmap->to_cnt++;
+ src_cnt++;
+ j++;
+ }
+
+ if (!P(blocks, disks)) {
+ pq[0] = 0;
+ dma_flags |= DMA_PREP_PQ_DISABLE_P;
+ } else {
+ pq[0] = dma_map_page(dev, P(blocks, disks),
+ offset, len,
+ DMA_TO_DEVICE);
+ unmap->addr[j++] = pq[0];
+ unmap->to_cnt++;
+ }
+ if (!Q(blocks, disks)) {
+ pq[1] = 0;
+ dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+ } else {
+ pq[1] = dma_map_page(dev, Q(blocks, disks),
+ offset, len,
+ DMA_TO_DEVICE);
+ unmap->addr[j++] = pq[1];
+ unmap->to_cnt++;
+ }
+
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_flags |= DMA_PREP_FENCE;
+ for (;;) {
+ tx = device->device_prep_dma_pq_val(chan, pq,
+ unmap->addr,
+ src_cnt,
+ coefs,
+ len, pqres,
+ dma_flags);
+ if (likely(tx))
+ break;
+ async_tx_quiesce(&submit->depend_tx);
+ dma_async_issue_pending(chan);
+ }
+
+ dma_set_unmap(tx, unmap);
+ async_tx_submit(chan, tx, submit);
+
+ return tx;
+ } else {
+ struct page *p_src = P(blocks, disks);
+ struct page *q_src = Q(blocks, disks);
+ enum async_tx_flags flags_orig = submit->flags;
+ dma_async_tx_callback cb_fn_orig = submit->cb_fn;
+ void *scribble = submit->scribble;
+ void *cb_param_orig = submit->cb_param;
+ void *p, *q, *s;
+
+ pr_debug("%s: (sync) disks: %d len: %zu\n",
+ __func__, disks, len);
+
+ /* caller must provide a temporary result buffer and
+ * allow the input parameters to be preserved
+ */
+ BUG_ON(!spare || !scribble);
+
+ /* wait for any prerequisite operations */
+ async_tx_quiesce(&submit->depend_tx);
+
+ /* recompute p and/or q into the temporary buffer and then
+ * check to see the result matches the current value
+ */
+ tx = NULL;
+ *pqres = 0;
+ if (p_src) {
+ init_async_submit(submit, ASYNC_TX_XOR_ZERO_DST, NULL,
+ NULL, NULL, scribble);
+ tx = async_xor(spare, blocks, offset, disks-2, len, submit);
+ async_tx_quiesce(&tx);
+ p = page_address(p_src) + offset;
+ s = page_address(spare) + offset;
+ *pqres |= !!memcmp(p, s, len) << SUM_CHECK_P;
+ }
+
+ if (q_src) {
+ P(blocks, disks) = NULL;
+ Q(blocks, disks) = spare;
+ init_async_submit(submit, 0, NULL, NULL, NULL, scribble);
+ tx = async_gen_syndrome(blocks, offset, disks, len, submit);
+ async_tx_quiesce(&tx);
+ q = page_address(q_src) + offset;
+ s = page_address(spare) + offset;
+ *pqres |= !!memcmp(q, s, len) << SUM_CHECK_Q;
+ }
+
+ /* restore P, Q and submit */
+ P(blocks, disks) = p_src;
+ Q(blocks, disks) = q_src;
+
+ submit->cb_fn = cb_fn_orig;
+ submit->cb_param = cb_param_orig;
+ submit->flags = flags_orig;
+ async_tx_sync_epilog(submit);
+
+ return NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(async_syndrome_val);
+
+static int __init async_pq_init(void)
+{
+ pq_scribble_page = alloc_page(GFP_KERNEL);
+
+ if (pq_scribble_page)
+ return 0;
+
+ pr_err("%s: failed to allocate required spare page\n", __func__);
+
+ return -ENOMEM;
+}
+
+static void __exit async_pq_exit(void)
+{
+ put_page(pq_scribble_page);
+}
+
+module_init(async_pq_init);
+module_exit(async_pq_exit);
+
+MODULE_DESCRIPTION("asynchronous raid6 syndrome generation/validation");
+MODULE_LICENSE("GPL");
diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c
new file mode 100644
index 000000000..934a84981
--- /dev/null
+++ b/crypto/async_tx/async_raid6_recov.c
@@ -0,0 +1,531 @@
+/*
+ * Asynchronous RAID-6 recovery calculations ASYNC_TX API.
+ * Copyright(c) 2009 Intel Corporation
+ *
+ * based on raid6recov.c:
+ * Copyright 2002 H. Peter Anvin
+ *
+ * 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., 51
+ * Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/dma-mapping.h>
+#include <linux/raid/pq.h>
+#include <linux/async_tx.h>
+#include <linux/dmaengine.h>
+
+static struct dma_async_tx_descriptor *
+async_sum_product(struct page *dest, struct page **srcs, unsigned char *coef,
+ size_t len, struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
+ &dest, 1, srcs, 2, len);
+ struct dma_device *dma = chan ? chan->device : NULL;
+ struct dmaengine_unmap_data *unmap = NULL;
+ const u8 *amul, *bmul;
+ u8 ax, bx;
+ u8 *a, *b, *c;
+
+ if (dma)
+ unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO);
+
+ if (unmap) {
+ struct device *dev = dma->dev;
+ dma_addr_t pq[2];
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
+
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_flags |= DMA_PREP_FENCE;
+ unmap->addr[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE);
+ unmap->addr[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE);
+ unmap->to_cnt = 2;
+
+ unmap->addr[2] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+ unmap->bidi_cnt = 1;
+ /* engine only looks at Q, but expects it to follow P */
+ pq[1] = unmap->addr[2];
+
+ unmap->len = len;
+ tx = dma->device_prep_dma_pq(chan, pq, unmap->addr, 2, coef,
+ len, dma_flags);
+ if (tx) {
+ dma_set_unmap(tx, unmap);
+ async_tx_submit(chan, tx, submit);
+ dmaengine_unmap_put(unmap);
+ return tx;
+ }
+
+ /* could not get a descriptor, unmap and fall through to
+ * the synchronous path
+ */
+ dmaengine_unmap_put(unmap);
+ }
+
+ /* run the operation synchronously */
+ async_tx_quiesce(&submit->depend_tx);
+ amul = raid6_gfmul[coef[0]];
+ bmul = raid6_gfmul[coef[1]];
+ a = page_address(srcs[0]);
+ b = page_address(srcs[1]);
+ c = page_address(dest);
+
+ while (len--) {
+ ax = amul[*a++];
+ bx = bmul[*b++];
+ *c++ = ax ^ bx;
+ }
+
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
+ struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_PQ,
+ &dest, 1, &src, 1, len);
+ struct dma_device *dma = chan ? chan->device : NULL;
+ struct dmaengine_unmap_data *unmap = NULL;
+ const u8 *qmul; /* Q multiplier table */
+ u8 *d, *s;
+
+ if (dma)
+ unmap = dmaengine_get_unmap_data(dma->dev, 3, GFP_NOIO);
+
+ if (unmap) {
+ dma_addr_t dma_dest[2];
+ struct device *dev = dma->dev;
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
+
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_flags |= DMA_PREP_FENCE;
+ unmap->addr[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE);
+ unmap->to_cnt++;
+ unmap->addr[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+ dma_dest[1] = unmap->addr[1];
+ unmap->bidi_cnt++;
+ unmap->len = len;
+
+ /* this looks funny, but the engine looks for Q at
+ * dma_dest[1] and ignores dma_dest[0] as a dest
+ * due to DMA_PREP_PQ_DISABLE_P
+ */
+ tx = dma->device_prep_dma_pq(chan, dma_dest, unmap->addr,
+ 1, &coef, len, dma_flags);
+
+ if (tx) {
+ dma_set_unmap(tx, unmap);
+ dmaengine_unmap_put(unmap);
+ async_tx_submit(chan, tx, submit);
+ return tx;
+ }
+
+ /* could not get a descriptor, unmap and fall through to
+ * the synchronous path
+ */
+ dmaengine_unmap_put(unmap);
+ }
+
+ /* no channel available, or failed to allocate a descriptor, so
+ * perform the operation synchronously
+ */
+ async_tx_quiesce(&submit->depend_tx);
+ qmul = raid6_gfmul[coef];
+ d = page_address(dest);
+ s = page_address(src);
+
+ while (len--)
+ *d++ = qmul[*s++];
+
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+__2data_recov_4(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct page *p, *q, *a, *b;
+ struct page *srcs[2];
+ unsigned char coef[2];
+ enum async_tx_flags flags = submit->flags;
+ dma_async_tx_callback cb_fn = submit->cb_fn;
+ void *cb_param = submit->cb_param;
+ void *scribble = submit->scribble;
+
+ p = blocks[disks-2];
+ q = blocks[disks-1];
+
+ a = blocks[faila];
+ b = blocks[failb];
+
+ /* in the 4 disk case P + Pxy == P and Q + Qxy == Q */
+ /* Dx = A*(P+Pxy) + B*(Q+Qxy) */
+ srcs[0] = p;
+ srcs[1] = q;
+ coef[0] = raid6_gfexi[failb-faila];
+ coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_sum_product(b, srcs, coef, bytes, submit);
+
+ /* Dy = P+Pxy+Dx */
+ srcs[0] = p;
+ srcs[1] = b;
+ init_async_submit(submit, flags | ASYNC_TX_XOR_ZERO_DST, tx, cb_fn,
+ cb_param, scribble);
+ tx = async_xor(a, srcs, 0, 2, bytes, submit);
+
+ return tx;
+
+}
+
+static struct dma_async_tx_descriptor *
+__2data_recov_5(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct page *p, *q, *g, *dp, *dq;
+ struct page *srcs[2];
+ unsigned char coef[2];
+ enum async_tx_flags flags = submit->flags;
+ dma_async_tx_callback cb_fn = submit->cb_fn;
+ void *cb_param = submit->cb_param;
+ void *scribble = submit->scribble;
+ int good_srcs, good, i;
+
+ good_srcs = 0;
+ good = -1;
+ for (i = 0; i < disks-2; i++) {
+ if (blocks[i] == NULL)
+ continue;
+ if (i == faila || i == failb)
+ continue;
+ good = i;
+ good_srcs++;
+ }
+ BUG_ON(good_srcs > 1);
+
+ p = blocks[disks-2];
+ q = blocks[disks-1];
+ g = blocks[good];
+
+ /* Compute syndrome with zero for the missing data pages
+ * Use the dead data pages as temporary storage for delta p and
+ * delta q
+ */
+ dp = blocks[faila];
+ dq = blocks[failb];
+
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_memcpy(dp, g, 0, 0, bytes, submit);
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit);
+
+ /* compute P + Pxy */
+ srcs[0] = dp;
+ srcs[1] = p;
+ init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
+ NULL, NULL, scribble);
+ tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+
+ /* compute Q + Qxy */
+ srcs[0] = dq;
+ srcs[1] = q;
+ init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
+ NULL, NULL, scribble);
+ tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+
+ /* Dx = A*(P+Pxy) + B*(Q+Qxy) */
+ srcs[0] = dp;
+ srcs[1] = dq;
+ coef[0] = raid6_gfexi[failb-faila];
+ coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_sum_product(dq, srcs, coef, bytes, submit);
+
+ /* Dy = P+Pxy+Dx */
+ srcs[0] = dp;
+ srcs[1] = dq;
+ init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
+ cb_param, scribble);
+ tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+
+ return tx;
+}
+
+static struct dma_async_tx_descriptor *
+__2data_recov_n(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct page *p, *q, *dp, *dq;
+ struct page *srcs[2];
+ unsigned char coef[2];
+ enum async_tx_flags flags = submit->flags;
+ dma_async_tx_callback cb_fn = submit->cb_fn;
+ void *cb_param = submit->cb_param;
+ void *scribble = submit->scribble;
+
+ p = blocks[disks-2];
+ q = blocks[disks-1];
+
+ /* Compute syndrome with zero for the missing data pages
+ * Use the dead data pages as temporary storage for
+ * delta p and delta q
+ */
+ dp = blocks[faila];
+ blocks[faila] = NULL;
+ blocks[disks-2] = dp;
+ dq = blocks[failb];
+ blocks[failb] = NULL;
+ blocks[disks-1] = dq;
+
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_gen_syndrome(blocks, 0, disks, bytes, submit);
+
+ /* Restore pointer table */
+ blocks[faila] = dp;
+ blocks[failb] = dq;
+ blocks[disks-2] = p;
+ blocks[disks-1] = q;
+
+ /* compute P + Pxy */
+ srcs[0] = dp;
+ srcs[1] = p;
+ init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
+ NULL, NULL, scribble);
+ tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+
+ /* compute Q + Qxy */
+ srcs[0] = dq;
+ srcs[1] = q;
+ init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
+ NULL, NULL, scribble);
+ tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+
+ /* Dx = A*(P+Pxy) + B*(Q+Qxy) */
+ srcs[0] = dp;
+ srcs[1] = dq;
+ coef[0] = raid6_gfexi[failb-faila];
+ coef[1] = raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]];
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_sum_product(dq, srcs, coef, bytes, submit);
+
+ /* Dy = P+Pxy+Dx */
+ srcs[0] = dp;
+ srcs[1] = dq;
+ init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
+ cb_param, scribble);
+ tx = async_xor(dp, srcs, 0, 2, bytes, submit);
+
+ return tx;
+}
+
+/**
+ * async_raid6_2data_recov - asynchronously calculate two missing data blocks
+ * @disks: number of disks in the RAID-6 array
+ * @bytes: block size
+ * @faila: first failed drive index
+ * @failb: second failed drive index
+ * @blocks: array of source pointers where the last two entries are p and q
+ * @submit: submission/completion modifiers
+ */
+struct dma_async_tx_descriptor *
+async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
+{
+ void *scribble = submit->scribble;
+ int non_zero_srcs, i;
+
+ BUG_ON(faila == failb);
+ if (failb < faila)
+ swap(faila, failb);
+
+ pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
+
+ /* if a dma resource is not available or a scribble buffer is not
+ * available punt to the synchronous path. In the 'dma not
+ * available' case be sure to use the scribble buffer to
+ * preserve the content of 'blocks' as the caller intended.
+ */
+ if (!async_dma_find_channel(DMA_PQ) || !scribble) {
+ void **ptrs = scribble ? scribble : (void **) blocks;
+
+ async_tx_quiesce(&submit->depend_tx);
+ for (i = 0; i < disks; i++)
+ if (blocks[i] == NULL)
+ ptrs[i] = (void *) raid6_empty_zero_page;
+ else
+ ptrs[i] = page_address(blocks[i]);
+
+ raid6_2data_recov(disks, bytes, faila, failb, ptrs);
+
+ async_tx_sync_epilog(submit);
+
+ return NULL;
+ }
+
+ non_zero_srcs = 0;
+ for (i = 0; i < disks-2 && non_zero_srcs < 4; i++)
+ if (blocks[i])
+ non_zero_srcs++;
+ switch (non_zero_srcs) {
+ case 0:
+ case 1:
+ /* There must be at least 2 sources - the failed devices. */
+ BUG();
+
+ case 2:
+ /* dma devices do not uniformly understand a zero source pq
+ * operation (in contrast to the synchronous case), so
+ * explicitly handle the special case of a 4 disk array with
+ * both data disks missing.
+ */
+ return __2data_recov_4(disks, bytes, faila, failb, blocks, submit);
+ case 3:
+ /* dma devices do not uniformly understand a single
+ * source pq operation (in contrast to the synchronous
+ * case), so explicitly handle the special case of a 5 disk
+ * array with 2 of 3 data disks missing.
+ */
+ return __2data_recov_5(disks, bytes, faila, failb, blocks, submit);
+ default:
+ return __2data_recov_n(disks, bytes, faila, failb, blocks, submit);
+ }
+}
+EXPORT_SYMBOL_GPL(async_raid6_2data_recov);
+
+/**
+ * async_raid6_datap_recov - asynchronously calculate a data and the 'p' block
+ * @disks: number of disks in the RAID-6 array
+ * @bytes: block size
+ * @faila: failed drive index
+ * @blocks: array of source pointers where the last two entries are p and q
+ * @submit: submission/completion modifiers
+ */
+struct dma_async_tx_descriptor *
+async_raid6_datap_recov(int disks, size_t bytes, int faila,
+ struct page **blocks, struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct page *p, *q, *dq;
+ u8 coef;
+ enum async_tx_flags flags = submit->flags;
+ dma_async_tx_callback cb_fn = submit->cb_fn;
+ void *cb_param = submit->cb_param;
+ void *scribble = submit->scribble;
+ int good_srcs, good, i;
+ struct page *srcs[2];
+
+ pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
+
+ /* if a dma resource is not available or a scribble buffer is not
+ * available punt to the synchronous path. In the 'dma not
+ * available' case be sure to use the scribble buffer to
+ * preserve the content of 'blocks' as the caller intended.
+ */
+ if (!async_dma_find_channel(DMA_PQ) || !scribble) {
+ void **ptrs = scribble ? scribble : (void **) blocks;
+
+ async_tx_quiesce(&submit->depend_tx);
+ for (i = 0; i < disks; i++)
+ if (blocks[i] == NULL)
+ ptrs[i] = (void*)raid6_empty_zero_page;
+ else
+ ptrs[i] = page_address(blocks[i]);
+
+ raid6_datap_recov(disks, bytes, faila, ptrs);
+
+ async_tx_sync_epilog(submit);
+
+ return NULL;
+ }
+
+ good_srcs = 0;
+ good = -1;
+ for (i = 0; i < disks-2; i++) {
+ if (i == faila)
+ continue;
+ if (blocks[i]) {
+ good = i;
+ good_srcs++;
+ if (good_srcs > 1)
+ break;
+ }
+ }
+ BUG_ON(good_srcs == 0);
+
+ p = blocks[disks-2];
+ q = blocks[disks-1];
+
+ /* Compute syndrome with zero for the missing data page
+ * Use the dead data page as temporary storage for delta q
+ */
+ dq = blocks[faila];
+ blocks[faila] = NULL;
+ blocks[disks-1] = dq;
+
+ /* in the 4-disk case we only need to perform a single source
+ * multiplication with the one good data block.
+ */
+ if (good_srcs == 1) {
+ struct page *g = blocks[good];
+
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
+ scribble);
+ tx = async_memcpy(p, g, 0, 0, bytes, submit);
+
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
+ scribble);
+ tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit);
+ } else {
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
+ scribble);
+ tx = async_gen_syndrome(blocks, 0, disks, bytes, submit);
+ }
+
+ /* Restore pointer table */
+ blocks[faila] = dq;
+ blocks[disks-1] = q;
+
+ /* calculate g^{-faila} */
+ coef = raid6_gfinv[raid6_gfexp[faila]];
+
+ srcs[0] = dq;
+ srcs[1] = q;
+ init_async_submit(submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
+ NULL, NULL, scribble);
+ tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+
+ init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
+ tx = async_mult(dq, dq, coef, bytes, submit);
+
+ srcs[0] = p;
+ srcs[1] = dq;
+ init_async_submit(submit, flags | ASYNC_TX_XOR_DROP_DST, tx, cb_fn,
+ cb_param, scribble);
+ tx = async_xor(p, srcs, 0, 2, bytes, submit);
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_raid6_datap_recov);
+
+MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
+MODULE_DESCRIPTION("asynchronous RAID-6 recovery api");
+MODULE_LICENSE("GPL");
diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c
new file mode 100644
index 000000000..39ea4791a
--- /dev/null
+++ b/crypto/async_tx/async_tx.c
@@ -0,0 +1,294 @@
+/*
+ * core routines for the asynchronous memory transfer/transform api
+ *
+ * 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>
+ *
+ * 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.
+ *
+ */
+#include <linux/rculist.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/async_tx.h>
+
+#ifdef CONFIG_DMA_ENGINE
+static int __init async_tx_init(void)
+{
+ async_dmaengine_get();
+
+ printk(KERN_INFO "async_tx: api initialized (async)\n");
+
+ return 0;
+}
+
+static void __exit async_tx_exit(void)
+{
+ async_dmaengine_put();
+}
+
+module_init(async_tx_init);
+module_exit(async_tx_exit);
+
+/**
+ * __async_tx_find_channel - find a channel to carry out the operation or let
+ * the transaction execute synchronously
+ * @submit: transaction dependency and submission modifiers
+ * @tx_type: transaction type
+ */
+struct dma_chan *
+__async_tx_find_channel(struct async_submit_ctl *submit,
+ enum dma_transaction_type tx_type)
+{
+ struct dma_async_tx_descriptor *depend_tx = submit->depend_tx;
+
+ /* see if we can keep the chain on one channel */
+ if (depend_tx &&
+ dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))
+ return depend_tx->chan;
+ return async_dma_find_channel(tx_type);
+}
+EXPORT_SYMBOL_GPL(__async_tx_find_channel);
+#endif
+
+
+/**
+ * async_tx_channel_switch - queue an interrupt descriptor with a dependency
+ * pre-attached.
+ * @depend_tx: the operation that must finish before the new operation runs
+ * @tx: the new operation
+ */
+static void
+async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
+ struct dma_async_tx_descriptor *tx)
+{
+ struct dma_chan *chan = depend_tx->chan;
+ struct dma_device *device = chan->device;
+ struct dma_async_tx_descriptor *intr_tx = (void *) ~0;
+
+ /* first check to see if we can still append to depend_tx */
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx) && depend_tx->chan == tx->chan) {
+ txd_chain(depend_tx, tx);
+ intr_tx = NULL;
+ }
+ txd_unlock(depend_tx);
+
+ /* attached dependency, flush the parent channel */
+ if (!intr_tx) {
+ device->device_issue_pending(chan);
+ return;
+ }
+
+ /* see if we can schedule an interrupt
+ * otherwise poll for completion
+ */
+ if (dma_has_cap(DMA_INTERRUPT, device->cap_mask))
+ intr_tx = device->device_prep_dma_interrupt(chan, 0);
+ else
+ intr_tx = NULL;
+
+ if (intr_tx) {
+ intr_tx->callback = NULL;
+ intr_tx->callback_param = NULL;
+ /* safe to chain outside the lock since we know we are
+ * not submitted yet
+ */
+ txd_chain(intr_tx, tx);
+
+ /* check if we need to append */
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx)) {
+ txd_chain(depend_tx, intr_tx);
+ async_tx_ack(intr_tx);
+ intr_tx = NULL;
+ }
+ txd_unlock(depend_tx);
+
+ if (intr_tx) {
+ txd_clear_parent(intr_tx);
+ intr_tx->tx_submit(intr_tx);
+ async_tx_ack(intr_tx);
+ }
+ device->device_issue_pending(chan);
+ } else {
+ if (dma_wait_for_async_tx(depend_tx) != DMA_COMPLETE)
+ panic("%s: DMA error waiting for depend_tx\n",
+ __func__);
+ tx->tx_submit(tx);
+ }
+}
+
+
+/**
+ * submit_disposition - flags for routing an incoming operation
+ * @ASYNC_TX_SUBMITTED: we were able to append the new operation under the lock
+ * @ASYNC_TX_CHANNEL_SWITCH: when the lock is dropped schedule a channel switch
+ * @ASYNC_TX_DIRECT_SUBMIT: when the lock is dropped submit directly
+ *
+ * while holding depend_tx->lock we must avoid submitting new operations
+ * to prevent a circular locking dependency with drivers that already
+ * hold a channel lock when calling async_tx_run_dependencies.
+ */
+enum submit_disposition {
+ ASYNC_TX_SUBMITTED,
+ ASYNC_TX_CHANNEL_SWITCH,
+ ASYNC_TX_DIRECT_SUBMIT,
+};
+
+void
+async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
+ struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *depend_tx = submit->depend_tx;
+
+ tx->callback = submit->cb_fn;
+ tx->callback_param = submit->cb_param;
+
+ if (depend_tx) {
+ enum submit_disposition s;
+
+ /* sanity check the dependency chain:
+ * 1/ if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ * 2/ dependencies are 1:1 i.e. two transactions can
+ * not depend on the same parent
+ */
+ BUG_ON(async_tx_test_ack(depend_tx) || txd_next(depend_tx) ||
+ txd_parent(tx));
+
+ /* the lock prevents async_tx_run_dependencies from missing
+ * the setting of ->next when ->parent != NULL
+ */
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx)) {
+ /* we have a parent so we can not submit directly
+ * if we are staying on the same channel: append
+ * else: channel switch
+ */
+ if (depend_tx->chan == chan) {
+ txd_chain(depend_tx, tx);
+ s = ASYNC_TX_SUBMITTED;
+ } else
+ s = ASYNC_TX_CHANNEL_SWITCH;
+ } else {
+ /* we do not have a parent so we may be able to submit
+ * directly if we are staying on the same channel
+ */
+ if (depend_tx->chan == chan)
+ s = ASYNC_TX_DIRECT_SUBMIT;
+ else
+ s = ASYNC_TX_CHANNEL_SWITCH;
+ }
+ txd_unlock(depend_tx);
+
+ switch (s) {
+ case ASYNC_TX_SUBMITTED:
+ break;
+ case ASYNC_TX_CHANNEL_SWITCH:
+ async_tx_channel_switch(depend_tx, tx);
+ break;
+ case ASYNC_TX_DIRECT_SUBMIT:
+ txd_clear_parent(tx);
+ tx->tx_submit(tx);
+ break;
+ }
+ } else {
+ txd_clear_parent(tx);
+ tx->tx_submit(tx);
+ }
+
+ if (submit->flags & ASYNC_TX_ACK)
+ async_tx_ack(tx);
+
+ if (depend_tx)
+ async_tx_ack(depend_tx);
+}
+EXPORT_SYMBOL_GPL(async_tx_submit);
+
+/**
+ * async_trigger_callback - schedules the callback function to be run
+ * @submit: submission and completion parameters
+ *
+ * honored flags: ASYNC_TX_ACK
+ *
+ * The callback is run after any dependent operations have completed.
+ */
+struct dma_async_tx_descriptor *
+async_trigger_callback(struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan;
+ struct dma_device *device;
+ struct dma_async_tx_descriptor *tx;
+ struct dma_async_tx_descriptor *depend_tx = submit->depend_tx;
+
+ if (depend_tx) {
+ chan = depend_tx->chan;
+ device = chan->device;
+
+ /* see if we can schedule an interrupt
+ * otherwise poll for completion
+ */
+ if (device && !dma_has_cap(DMA_INTERRUPT, device->cap_mask))
+ device = NULL;
+
+ tx = device ? device->device_prep_dma_interrupt(chan, 0) : NULL;
+ } else
+ tx = NULL;
+
+ if (tx) {
+ pr_debug("%s: (async)\n", __func__);
+
+ async_tx_submit(chan, tx, submit);
+ } else {
+ pr_debug("%s: (sync)\n", __func__);
+
+ /* wait for any prerequisite operations */
+ async_tx_quiesce(&submit->depend_tx);
+
+ async_tx_sync_epilog(submit);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_trigger_callback);
+
+/**
+ * async_tx_quiesce - ensure tx is complete and freeable upon return
+ * @tx - transaction to quiesce
+ */
+void async_tx_quiesce(struct dma_async_tx_descriptor **tx)
+{
+ if (*tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(async_tx_test_ack(*tx));
+ if (dma_wait_for_async_tx(*tx) != DMA_COMPLETE)
+ panic("%s: DMA error waiting for transaction\n",
+ __func__);
+ async_tx_ack(*tx);
+ *tx = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(async_tx_quiesce);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Asynchronous Bulk Memory Transactions API");
+MODULE_LICENSE("GPL");
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
new file mode 100644
index 000000000..e1bce26cd
--- /dev/null
+++ b/crypto/async_tx/async_xor.c
@@ -0,0 +1,345 @@
+/*
+ * xor offload engine api
+ *
+ * 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>
+ *
+ * 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.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/raid/xor.h>
+#include <linux/async_tx.h>
+
+/* do_async_xor - dma map the pages and perform the xor with an engine */
+static __async_inline struct dma_async_tx_descriptor *
+do_async_xor(struct dma_chan *chan, struct dmaengine_unmap_data *unmap,
+ struct async_submit_ctl *submit)
+{
+ struct dma_device *dma = chan->device;
+ struct dma_async_tx_descriptor *tx = NULL;
+ dma_async_tx_callback cb_fn_orig = submit->cb_fn;
+ void *cb_param_orig = submit->cb_param;
+ enum async_tx_flags flags_orig = submit->flags;
+ enum dma_ctrl_flags dma_flags = 0;
+ int src_cnt = unmap->to_cnt;
+ int xor_src_cnt;
+ dma_addr_t dma_dest = unmap->addr[unmap->to_cnt];
+ dma_addr_t *src_list = unmap->addr;
+
+ while (src_cnt) {
+ dma_addr_t tmp;
+
+ submit->flags = flags_orig;
+ xor_src_cnt = min(src_cnt, (int)dma->max_xor);
+ /* if we are submitting additional xors, leave the chain open
+ * and clear the callback parameters
+ */
+ if (src_cnt > xor_src_cnt) {
+ submit->flags &= ~ASYNC_TX_ACK;
+ submit->flags |= ASYNC_TX_FENCE;
+ submit->cb_fn = NULL;
+ submit->cb_param = NULL;
+ } else {
+ submit->cb_fn = cb_fn_orig;
+ submit->cb_param = cb_param_orig;
+ }
+ if (submit->cb_fn)
+ dma_flags |= DMA_PREP_INTERRUPT;
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_flags |= DMA_PREP_FENCE;
+
+ /* Drivers force forward progress in case they can not provide a
+ * descriptor
+ */
+ tmp = src_list[0];
+ if (src_list > unmap->addr)
+ src_list[0] = dma_dest;
+ tx = dma->device_prep_dma_xor(chan, dma_dest, src_list,
+ xor_src_cnt, unmap->len,
+ dma_flags);
+
+ if (unlikely(!tx))
+ async_tx_quiesce(&submit->depend_tx);
+
+ /* spin wait for the preceding transactions to complete */
+ while (unlikely(!tx)) {
+ dma_async_issue_pending(chan);
+ tx = dma->device_prep_dma_xor(chan, dma_dest,
+ src_list,
+ xor_src_cnt, unmap->len,
+ dma_flags);
+ }
+ src_list[0] = tmp;
+
+ dma_set_unmap(tx, unmap);
+ async_tx_submit(chan, tx, submit);
+ submit->depend_tx = tx;
+
+ if (src_cnt > xor_src_cnt) {
+ /* drop completed sources */
+ src_cnt -= xor_src_cnt;
+ /* use the intermediate result a source */
+ src_cnt++;
+ src_list += xor_src_cnt - 1;
+ } else
+ break;
+ }
+
+ return tx;
+}
+
+static void
+do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
+ int src_cnt, size_t len, struct async_submit_ctl *submit)
+{
+ int i;
+ int xor_src_cnt = 0;
+ int src_off = 0;
+ void *dest_buf;
+ void **srcs;
+
+ if (submit->scribble)
+ srcs = submit->scribble;
+ else
+ srcs = (void **) src_list;
+
+ /* convert to buffer pointers */
+ for (i = 0; i < src_cnt; i++)
+ if (src_list[i])
+ srcs[xor_src_cnt++] = page_address(src_list[i]) + offset;
+ src_cnt = xor_src_cnt;
+ /* set destination address */
+ dest_buf = page_address(dest) + offset;
+
+ if (submit->flags & ASYNC_TX_XOR_ZERO_DST)
+ memset(dest_buf, 0, len);
+
+ while (src_cnt > 0) {
+ /* process up to 'MAX_XOR_BLOCKS' sources */
+ xor_src_cnt = min(src_cnt, MAX_XOR_BLOCKS);
+ xor_blocks(xor_src_cnt, len, dest_buf, &srcs[src_off]);
+
+ /* drop completed sources */
+ src_cnt -= xor_src_cnt;
+ src_off += xor_src_cnt;
+ }
+
+ async_tx_sync_epilog(submit);
+}
+
+/**
+ * async_xor - attempt to xor a set of blocks with a dma engine.
+ * @dest: destination page
+ * @src_list: array of source pages
+ * @offset: common src/dst offset to start transaction
+ * @src_cnt: number of source pages
+ * @len: length in bytes
+ * @submit: submission / completion modifiers
+ *
+ * honored flags: ASYNC_TX_ACK, ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DST
+ *
+ * xor_blocks always uses the dest as a source so the
+ * ASYNC_TX_XOR_ZERO_DST flag must be set to not include dest data in
+ * the calculation. The assumption with dma eninges is that they only
+ * use the destination buffer as a source when it is explicity specified
+ * in the source list.
+ *
+ * src_list note: if the dest is also a source it must be at index zero.
+ * The contents of this array will be overwritten if a scribble region
+ * is not specified.
+ */
+struct dma_async_tx_descriptor *
+async_xor(struct page *dest, struct page **src_list, unsigned int offset,
+ int src_cnt, size_t len, struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR,
+ &dest, 1, src_list,
+ src_cnt, len);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dmaengine_unmap_data *unmap = NULL;
+
+ BUG_ON(src_cnt <= 1);
+
+ if (device)
+ unmap = dmaengine_get_unmap_data(device->dev, src_cnt+1, GFP_NOIO);
+
+ if (unmap && is_dma_xor_aligned(device, offset, 0, len)) {
+ struct dma_async_tx_descriptor *tx;
+ int i, j;
+
+ /* run the xor asynchronously */
+ pr_debug("%s (async): len: %zu\n", __func__, len);
+
+ unmap->len = len;
+ for (i = 0, j = 0; i < src_cnt; i++) {
+ if (!src_list[i])
+ continue;
+ unmap->to_cnt++;
+ unmap->addr[j++] = dma_map_page(device->dev, src_list[i],
+ offset, len, DMA_TO_DEVICE);
+ }
+
+ /* map it bidirectional as it may be re-used as a source */
+ unmap->addr[j] = dma_map_page(device->dev, dest, offset, len,
+ DMA_BIDIRECTIONAL);
+ unmap->bidi_cnt = 1;
+
+ tx = do_async_xor(chan, unmap, submit);
+ dmaengine_unmap_put(unmap);
+ return tx;
+ } else {
+ dmaengine_unmap_put(unmap);
+ /* run the xor synchronously */
+ pr_debug("%s (sync): len: %zu\n", __func__, len);
+ WARN_ONCE(chan, "%s: no space for dma address conversion\n",
+ __func__);
+
+ /* in the sync case the dest is an implied source
+ * (assumes the dest is the first source)
+ */
+ if (submit->flags & ASYNC_TX_XOR_DROP_DST) {
+ src_cnt--;
+ src_list++;
+ }
+
+ /* wait for any prerequisite operations */
+ async_tx_quiesce(&submit->depend_tx);
+
+ do_sync_xor(dest, src_list, offset, src_cnt, len, submit);
+
+ return NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(async_xor);
+
+static int page_is_zero(struct page *p, unsigned int offset, size_t len)
+{
+ return !memchr_inv(page_address(p) + offset, 0, len);
+}
+
+static inline struct dma_chan *
+xor_val_chan(struct async_submit_ctl *submit, struct page *dest,
+ struct page **src_list, int src_cnt, size_t len)
+{
+ #ifdef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+ return NULL;
+ #endif
+ return async_tx_find_channel(submit, DMA_XOR_VAL, &dest, 1, src_list,
+ src_cnt, len);
+}
+
+/**
+ * async_xor_val - attempt a xor parity check with a dma engine.
+ * @dest: destination page used if the xor is performed synchronously
+ * @src_list: array of source pages
+ * @offset: offset in pages to start transaction
+ * @src_cnt: number of source pages
+ * @len: length in bytes
+ * @result: 0 if sum == 0 else non-zero
+ * @submit: submission / completion modifiers
+ *
+ * honored flags: ASYNC_TX_ACK
+ *
+ * src_list note: if the dest is also a source it must be at index zero.
+ * The contents of this array will be overwritten if a scribble region
+ * is not specified.
+ */
+struct dma_async_tx_descriptor *
+async_xor_val(struct page *dest, struct page **src_list, unsigned int offset,
+ int src_cnt, size_t len, enum sum_check_flags *result,
+ struct async_submit_ctl *submit)
+{
+ struct dma_chan *chan = xor_val_chan(submit, dest, src_list, src_cnt, len);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct dmaengine_unmap_data *unmap = NULL;
+
+ BUG_ON(src_cnt <= 1);
+
+ if (device)
+ unmap = dmaengine_get_unmap_data(device->dev, src_cnt, GFP_NOIO);
+
+ if (unmap && src_cnt <= device->max_xor &&
+ is_dma_xor_aligned(device, offset, 0, len)) {
+ unsigned long dma_prep_flags = 0;
+ int i;
+
+ pr_debug("%s: (async) len: %zu\n", __func__, len);
+
+ if (submit->cb_fn)
+ dma_prep_flags |= DMA_PREP_INTERRUPT;
+ if (submit->flags & ASYNC_TX_FENCE)
+ dma_prep_flags |= DMA_PREP_FENCE;
+
+ for (i = 0; i < src_cnt; i++) {
+ unmap->addr[i] = dma_map_page(device->dev, src_list[i],
+ offset, len, DMA_TO_DEVICE);
+ unmap->to_cnt++;
+ }
+ unmap->len = len;
+
+ tx = device->device_prep_dma_xor_val(chan, unmap->addr, src_cnt,
+ len, result,
+ dma_prep_flags);
+ if (unlikely(!tx)) {
+ async_tx_quiesce(&submit->depend_tx);
+
+ while (!tx) {
+ dma_async_issue_pending(chan);
+ tx = device->device_prep_dma_xor_val(chan,
+ unmap->addr, src_cnt, len, result,
+ dma_prep_flags);
+ }
+ }
+ dma_set_unmap(tx, unmap);
+ async_tx_submit(chan, tx, submit);
+ } else {
+ enum async_tx_flags flags_orig = submit->flags;
+
+ pr_debug("%s: (sync) len: %zu\n", __func__, len);
+ WARN_ONCE(device && src_cnt <= device->max_xor,
+ "%s: no space for dma address conversion\n",
+ __func__);
+
+ submit->flags |= ASYNC_TX_XOR_DROP_DST;
+ submit->flags &= ~ASYNC_TX_ACK;
+
+ tx = async_xor(dest, src_list, offset, src_cnt, len, submit);
+
+ async_tx_quiesce(&tx);
+
+ *result = !page_is_zero(dest, offset, len) << SUM_CHECK_P;
+
+ async_tx_sync_epilog(submit);
+ submit->flags = flags_orig;
+ }
+ dmaengine_unmap_put(unmap);
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_xor_val);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("asynchronous xor/xor-zero-sum api");
+MODULE_LICENSE("GPL");
diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c
new file mode 100644
index 000000000..dad95f45b
--- /dev/null
+++ b/crypto/async_tx/raid6test.c
@@ -0,0 +1,253 @@
+/*
+ * asynchronous raid6 recovery self test
+ * Copyright (c) 2009, Intel Corporation.
+ *
+ * based on drivers/md/raid6test/test.c:
+ * Copyright 2002-2007 H. Peter Anvin
+ *
+ * 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.
+ *
+ */
+#include <linux/async_tx.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+#include <linux/random.h>
+#include <linux/module.h>
+
+#undef pr
+#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
+
+#define NDISKS 64 /* Including P and Q */
+
+static struct page *dataptrs[NDISKS];
+static addr_conv_t addr_conv[NDISKS];
+static struct page *data[NDISKS+3];
+static struct page *spare;
+static struct page *recovi;
+static struct page *recovj;
+
+static void callback(void *param)
+{
+ struct completion *cmp = param;
+
+ complete(cmp);
+}
+
+static void makedata(int disks)
+{
+ int i;
+
+ for (i = 0; i < disks; i++) {
+ prandom_bytes(page_address(data[i]), PAGE_SIZE);
+ dataptrs[i] = data[i];
+ }
+}
+
+static char disk_type(int d, int disks)
+{
+ if (d == disks - 2)
+ return 'P';
+ else if (d == disks - 1)
+ return 'Q';
+ else
+ return 'D';
+}
+
+/* Recover two failed blocks. */
+static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs)
+{
+ struct async_submit_ctl submit;
+ struct completion cmp;
+ struct dma_async_tx_descriptor *tx = NULL;
+ enum sum_check_flags result = ~0;
+
+ if (faila > failb)
+ swap(faila, failb);
+
+ if (failb == disks-1) {
+ if (faila == disks-2) {
+ /* P+Q failure. Just rebuild the syndrome. */
+ init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
+ tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
+ } else {
+ struct page *blocks[disks];
+ struct page *dest;
+ int count = 0;
+ int i;
+
+ /* data+Q failure. Reconstruct data from P,
+ * then rebuild syndrome
+ */
+ for (i = disks; i-- ; ) {
+ if (i == faila || i == failb)
+ continue;
+ blocks[count++] = ptrs[i];
+ }
+ dest = ptrs[faila];
+ init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
+ NULL, NULL, addr_conv);
+ tx = async_xor(dest, blocks, 0, count, bytes, &submit);
+
+ init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);
+ tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
+ }
+ } else {
+ if (failb == disks-2) {
+ /* data+P failure. */
+ init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
+ tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit);
+ } else {
+ /* data+data failure. */
+ init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
+ tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit);
+ }
+ }
+ init_completion(&cmp);
+ init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);
+ tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit);
+ async_tx_issue_pending(tx);
+
+ if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)
+ pr("%s: timeout! (faila: %d failb: %d disks: %d)\n",
+ __func__, faila, failb, disks);
+
+ if (result != 0)
+ pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n",
+ __func__, faila, failb, result);
+}
+
+static int test_disks(int i, int j, int disks)
+{
+ int erra, errb;
+
+ memset(page_address(recovi), 0xf0, PAGE_SIZE);
+ memset(page_address(recovj), 0xba, PAGE_SIZE);
+
+ dataptrs[i] = recovi;
+ dataptrs[j] = recovj;
+
+ raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs);
+
+ erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);
+ errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE);
+
+ pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n",
+ __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks),
+ (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB");
+
+ dataptrs[i] = data[i];
+ dataptrs[j] = data[j];
+
+ return erra || errb;
+}
+
+static int test(int disks, int *tests)
+{
+ struct dma_async_tx_descriptor *tx;
+ struct async_submit_ctl submit;
+ struct completion cmp;
+ int err = 0;
+ int i, j;
+
+ recovi = data[disks];
+ recovj = data[disks+1];
+ spare = data[disks+2];
+
+ makedata(disks);
+
+ /* Nuke syndromes */
+ memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);
+ memset(page_address(data[disks-1]), 0xee, PAGE_SIZE);
+
+ /* Generate assumed good syndrome */
+ init_completion(&cmp);
+ init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
+ tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit);
+ async_tx_issue_pending(tx);
+
+ if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {
+ pr("error: initial gen_syndrome(%d) timed out\n", disks);
+ return 1;
+ }
+
+ pr("testing the %d-disk case...\n", disks);
+ for (i = 0; i < disks-1; i++)
+ for (j = i+1; j < disks; j++) {
+ (*tests)++;
+ err += test_disks(i, j, disks);
+ }
+
+ return err;
+}
+
+
+static int raid6_test(void)
+{
+ int err = 0;
+ int tests = 0;
+ int i;
+
+ for (i = 0; i < NDISKS+3; i++) {
+ data[i] = alloc_page(GFP_KERNEL);
+ if (!data[i]) {
+ while (i--)
+ put_page(data[i]);
+ return -ENOMEM;
+ }
+ }
+
+ /* the 4-disk and 5-disk cases are special for the recovery code */
+ if (NDISKS > 4)
+ err += test(4, &tests);
+ if (NDISKS > 5)
+ err += test(5, &tests);
+ /* the 11 and 12 disk cases are special for ioatdma (p-disabled
+ * q-continuation without extended descriptor)
+ */
+ if (NDISKS > 12) {
+ err += test(11, &tests);
+ err += test(12, &tests);
+ }
+
+ /* the 24 disk case is special for ioatdma as it is the boudary point
+ * at which it needs to switch from 8-source ops to 16-source
+ * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set)
+ */
+ if (NDISKS > 24)
+ err += test(24, &tests);
+
+ err += test(NDISKS, &tests);
+
+ pr("\n");
+ pr("complete (%d tests, %d failure%s)\n",
+ tests, err, err == 1 ? "" : "s");
+
+ for (i = 0; i < NDISKS+3; i++)
+ put_page(data[i]);
+
+ return 0;
+}
+
+static void raid6_test_exit(void)
+{
+}
+
+/* when compiled-in wait for drivers to load first (assumes dma drivers
+ * are also compliled-in)
+ */
+late_initcall(raid6_test);
+module_exit(raid6_test_exit);
+MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
+MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");
+MODULE_LICENSE("GPL");