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Date: Thu, 22 Mar 2007 23:51:52 -0700
From: Dan Williams <dan.j.williams@...el.com>
To: neilb@...e.de, christopher.leech@...el.com,
linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org
Cc: akpm@...ux-foundation.org, torvalds@...ux-foundation.org,
yur@...raft.com, wd@...x.de, arjan@...ux.intel.com,
rmk+kernel@....linux.org.uk
Subject: [PATCH 2.6.21-rc4 03/15] dmaengine: add the async_tx api
async_tx is an api to describe a series of bulk memory
transfers/transforms. When possible these transactions are carried out by
asynchrounous dma engines. The api handles inter-transaction dependencies
and hides dma channel management from the client. When a dma engine is not
present the transaction is carried out via synchronous software routines.
Xor operations are handled by async_tx, to this end xor.c is moved into
drivers/dma and is changed to take an explicit destination address and
a series of sources to match the hardware engine implementation.
When CONFIG_DMA_ENGINE is not set the asynchrounous path is compiled away.
Changelog:
* fixed a leftover debug print
* don't allow callbacks in async_interrupt_cond
* fixed xor_block changes
* fixed usage of ASYNC_TX_XOR_DROP_DEST
* drop dma mapping methods, suggested by Chris Leech
* printk warning fixups from Andrew Morton
* don't use inline in C files, Adrian Bunk
* select the API when MD is enabled
Signed-off-by: Dan Williams <dan.j.williams@...el.com>
---
drivers/Makefile | 1
drivers/dma/Kconfig | 15 +
drivers/dma/Makefile | 1
drivers/dma/async_tx.c | 905 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/dma/xor.c | 153 ++++++++
drivers/md/Kconfig | 3
drivers/md/Makefile | 6
drivers/md/raid5.c | 52 +--
drivers/md/xor.c | 154 --------
include/linux/async_tx.h | 180 +++++++++
include/linux/raid/xor.h | 5
11 files changed, 1286 insertions(+), 189 deletions(-)
diff --git a/drivers/Makefile b/drivers/Makefile
index 3a718f5..2e8de9e 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_I2C) += i2c/
obj-$(CONFIG_W1) += w1/
obj-$(CONFIG_HWMON) += hwmon/
obj-$(CONFIG_PHONE) += telephony/
+obj-$(CONFIG_ASYNC_TX_DMA) += dma/
obj-$(CONFIG_MD) += md/
obj-$(CONFIG_BT) += bluetooth/
obj-$(CONFIG_ISDN) += isdn/
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 30d021d..292ddad 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -7,8 +7,8 @@ menu "DMA Engine support"
config DMA_ENGINE
bool "Support for DMA engines"
---help---
- DMA engines offload copy operations from the CPU to dedicated
- hardware, allowing the copies to happen asynchronously.
+ DMA engines offload bulk memory operations from the CPU to dedicated
+ hardware, allowing the operations to happen asynchronously.
comment "DMA Clients"
@@ -22,6 +22,16 @@ config NET_DMA
Since this is the main user of the DMA engine, it should be enabled;
say Y here.
+config ASYNC_TX_DMA
+ tristate "Asynchronous Bulk Memory Transfers/Transforms API"
+ ---help---
+ This enables the async_tx management layer for dma engines.
+ Subsystems coded to this API will use offload engines for bulk
+ memory operations where present. Software implementations are
+ called when a dma engine is not present or fails to allocate
+ memory to carry out the transaction.
+ Current subsystems ported to async_tx: MD_RAID4,5
+
comment "DMA Devices"
config INTEL_IOATDMA
@@ -30,5 +40,4 @@ config INTEL_IOATDMA
default m
---help---
Enable support for the Intel(R) I/OAT DMA engine.
-
endmenu
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index bdcfdbd..6a99341 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_DMA_ENGINE) += dmaengine.o
obj-$(CONFIG_NET_DMA) += iovlock.o
obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o
+obj-$(CONFIG_ASYNC_TX_DMA) += async_tx.o xor.o
diff --git a/drivers/dma/async_tx.c b/drivers/dma/async_tx.c
new file mode 100644
index 0000000..8f7e701
--- /dev/null
+++ b/drivers/dma/async_tx.c
@@ -0,0 +1,905 @@
+/*
+ * Copyright(c) 2006 Intel Corporation. All rights reserved.
+ *
+ * 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/dma-mapping.h>
+#include <linux/raid/xor.h>
+#include <linux/async_tx.h>
+
+#define ASYNC_TX_DEBUG 0
+#define PRINTK(x...) ((void)(ASYNC_TX_DEBUG && printk(x)))
+
+#ifdef CONFIG_DMA_ENGINE
+static struct dma_client *async_api_client;
+static struct async_channel_entry async_channel_htable[] = {
+ [DMA_MEMCPY] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_MEMCPY].list), },
+ [DMA_XOR] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_XOR].list), },
+ [DMA_PQ_XOR] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_PQ_XOR].list), },
+ [DMA_DUAL_XOR] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_DUAL_XOR].list), },
+ [DMA_PQ_UPDATE] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_PQ_UPDATE].list), },
+ [DMA_ZERO_SUM] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_ZERO_SUM].list), },
+ [DMA_PQ_ZERO_SUM] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_PQ_ZERO_SUM].list), },
+ [DMA_MEMSET] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_MEMSET].list), },
+ [DMA_MEMCPY_CRC32C] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_MEMCPY_CRC32C].list), },
+ [DMA_INTERRUPT] = { .list =
+ LIST_HEAD_INIT(async_channel_htable[DMA_INTERRUPT].list), },
+};
+
+struct async_channel_entry async_tx_master_list = {
+ .list = LIST_HEAD_INIT(async_tx_master_list.list),
+};
+EXPORT_SYMBOL_GPL(async_tx_master_list);
+
+static void
+free_dma_chan_ref(struct rcu_head *rcu)
+{
+ struct dma_chan_ref *ref;
+ ref = container_of(rcu, struct dma_chan_ref, rcu);
+ dma_chan_put(ref->chan);
+ kfree(ref);
+}
+
+static void
+init_dma_chan_ref(struct dma_chan_ref *ref, struct dma_chan *chan)
+{
+ INIT_LIST_HEAD(&ref->async_node);
+ INIT_RCU_HEAD(&ref->rcu);
+ ref->chan = chan;
+}
+
+static void
+dma_channel_add_remove(struct dma_client *client,
+ struct dma_chan *chan, enum dma_event event)
+{
+ unsigned long i, flags;
+ struct dma_chan_ref *master_ref, *ref;
+ struct async_channel_entry *channel_entry;
+
+ switch (event) {
+ case DMA_RESOURCE_ADDED:
+ PRINTK("async_tx: dma resource added (capabilities: %#lx)\n",
+ chan->device->capabilities);
+ /* add the channel to the generic management list */
+ master_ref = kmalloc(sizeof(*master_ref), GFP_KERNEL);
+ if (master_ref) {
+ /* keep a reference until async_tx is unloaded */
+ dma_chan_get(chan);
+ init_dma_chan_ref(master_ref, chan);
+ spin_lock_irqsave(&async_tx_master_list.lock, flags);
+ list_add_tail_rcu(&master_ref->async_node,
+ &async_tx_master_list.list);
+ spin_unlock_irqrestore(&async_tx_master_list.lock,
+ flags);
+ } else {
+ printk(KERN_WARNING "async_tx: unable to create"
+ " new master entry in response to"
+ " a DMA_RESOURCE_ADDED event"
+ " (-ENOMEM)\n");
+ return;
+ }
+
+ /* add an entry for each capability of this channel */
+ dma_async_for_each_tx_type(i) {
+ if (test_bit(i, &chan->device->capabilities))
+ ref = kmalloc(sizeof(*ref), GFP_KERNEL);
+ else
+ continue;
+
+ if (ref) {
+ channel_entry = &async_channel_htable[i];
+ init_dma_chan_ref(ref, chan);
+ spin_lock_irqsave(&channel_entry->lock, flags);
+ atomic_inc(&channel_entry->version);
+ list_add_tail_rcu(&ref->async_node,
+ &channel_entry->list);
+ spin_unlock_irqrestore(&channel_entry->lock,
+ flags);
+ } else {
+ printk(KERN_WARNING "async_tx: unable to create"
+ " new op-specific entry in response to"
+ " a DMA_RESOURCE_ADDED event"
+ " (-ENOMEM)\n");
+ return;
+ }
+ }
+ break;
+ case DMA_RESOURCE_REMOVED:
+ PRINTK("async_tx: dma resource removed (capabilities: %#lx)\n",
+ chan->device->capabilities);
+ dma_async_for_each_tx_type(i) {
+ if (!test_bit(i, &chan->device->capabilities))
+ continue;
+
+ channel_entry = &async_channel_htable[i];
+
+ spin_lock_irqsave(&channel_entry->lock, flags);
+ list_for_each_entry_rcu(ref, &channel_entry->list,
+ async_node) {
+ if (ref->chan == chan) {
+ atomic_inc(&channel_entry->version);
+ list_del_rcu(&ref->async_node);
+ call_rcu(&ref->rcu, free_dma_chan_ref);
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&channel_entry->lock, flags);
+ }
+ break;
+ case DMA_RESOURCE_SUSPEND:
+ case DMA_RESOURCE_RESUME:
+ printk(KERN_WARNING "async_tx: does not support dma channel"
+ " suspend/resume\n");
+ break;
+ default:
+ BUG();
+ }
+}
+
+static int __init
+async_tx_init(void)
+{
+ unsigned long i;
+ struct async_channel_entry *channel_entry;
+ int cpu;
+
+ spin_lock_init(&async_tx_master_list.lock);
+
+ dma_async_for_each_tx_type(i) {
+ channel_entry = &async_channel_htable[i];
+ spin_lock_init(&channel_entry->lock);
+ channel_entry->local_iter = alloc_percpu(struct async_iter_percpu);
+ if (!channel_entry->local_iter) {
+ i++;
+ goto err;
+ }
+
+ atomic_set(&channel_entry->version, 0);
+
+ for_each_possible_cpu(cpu) {
+ struct async_iter_percpu *local_iter =
+ channel_entry->local_iter;
+ per_cpu_ptr(local_iter, cpu)->iter = &channel_entry->list;
+ per_cpu_ptr(local_iter, cpu)->local_version = 0;
+ }
+ }
+
+ async_api_client = dma_async_client_register(dma_channel_add_remove);
+
+ if (!async_api_client)
+ goto err;
+
+ dma_async_client_chan_request(async_api_client, DMA_CHAN_REQUEST_ALL);
+
+ printk("async_tx: api initialized (async)\n");
+
+ return 0;
+err:
+ printk("async_tx: initialization failure\n");
+
+ while (--i >= 0)
+ free_percpu(async_channel_htable[i].local_iter);
+
+ return 1;
+}
+
+static void __exit async_tx_exit(void)
+{
+ unsigned long i, flags;
+ struct async_channel_entry *channel_entry;
+ struct dma_chan_ref *ref;
+
+ if (async_api_client)
+ dma_async_client_unregister(async_api_client);
+
+ dma_async_for_each_tx_type(i) {
+ channel_entry = &async_channel_htable[i];
+ if (channel_entry->local_iter)
+ free_percpu(channel_entry->local_iter);
+
+ /* free all the per operation channel references */
+ spin_lock_irqsave(&channel_entry->lock, flags);
+ list_for_each_entry_rcu(ref, &channel_entry->list, async_node) {
+ list_del_rcu(&ref->async_node);
+ call_rcu(&ref->rcu, free_dma_chan_ref);
+ }
+ spin_unlock_irqrestore(&channel_entry->lock, flags);
+ }
+
+ /* free all the channels on the master list */
+ spin_lock_irqsave(&async_tx_master_list.lock, flags);
+ list_for_each_entry_rcu(ref, &async_tx_master_list.list, async_node) {
+ dma_chan_put(ref->chan); /* permit backing devices to go away */
+ list_del_rcu(&ref->async_node);
+ call_rcu(&ref->rcu, free_dma_chan_ref);
+ }
+ spin_unlock_irqrestore(&async_tx_master_list.lock, flags);
+}
+
+/**
+ * async_tx_find_channel - find a channel to carry out the operation or let
+ * the transaction execute synchronously
+ * @depend_tx: transaction dependency
+ * @tx_type: transaction type
+ */
+static struct dma_chan *
+async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
+ enum dma_transaction_type tx_type)
+{
+ /* see if we can keep the chain on one channel */
+ if (depend_tx &&
+ test_bit(tx_type, &depend_tx->chan->device->capabilities))
+ return depend_tx->chan;
+ else {
+ int cpu;
+ struct async_channel_entry *channel_entry =
+ &async_channel_htable[tx_type];
+ struct async_iter_percpu *local_iter;
+ struct list_head *iter;
+ struct dma_chan *chan;
+
+ rcu_read_lock();
+ if (list_empty(&channel_entry->list)) {
+ rcu_read_unlock();
+ return NULL;
+ }
+
+ cpu = get_cpu();
+ local_iter = per_cpu_ptr(channel_entry->local_iter, cpu);
+ put_cpu();
+
+ /* ensure the percpu place holder is pointing to a
+ * valid list entry and get the next channel in the
+ * round robin
+ */
+ if (unlikely(local_iter->local_version !=
+ atomic_read(&channel_entry->version))) {
+ local_iter->local_version =
+ atomic_read(&channel_entry->version);
+ iter = channel_entry->list.next;
+ } else {
+ iter = local_iter->iter->next;
+ /* wrap around detect */
+ if (iter == &channel_entry->list)
+ iter = iter->next;
+ }
+
+ /* if we are still pointing to the head then the list
+ * recently became empty
+ */
+ if (iter == &channel_entry->list)
+ chan = NULL;
+ else {
+ local_iter->iter = iter;
+ chan = list_entry(iter, struct dma_chan_ref, async_node)->chan;
+ }
+ rcu_read_unlock();
+
+ return chan;
+ }
+}
+#else
+static int __init async_tx_init(void)
+{
+ printk("async_tx: api initialized (sync-only)\n");
+ return 0;
+}
+
+static void __exit async_tx_exit(void)
+{
+ do { } while (0);
+}
+
+static struct dma_chan *
+async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
+ enum dma_transaction_type tx_type)
+{
+ return NULL;
+}
+#endif
+
+static void
+async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
+ enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ tx->callback = callback;
+ tx->callback_param = callback_param;
+
+ /* set this new tx to run after depend_tx if:
+ * 1/ a dependency exists (depend_tx is !NULL)
+ * 2/ the tx can not be submitted to the current channel
+ */
+ if (depend_tx && depend_tx->chan != chan) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+
+ tx->parent = depend_tx;
+ spin_lock_bh(&depend_tx->lock);
+ list_add_tail(&tx->depend_node, &depend_tx->depend_list);
+ if (depend_tx->cookie == 0) {
+ struct dma_chan *dep_chan = depend_tx->chan;
+ struct dma_device *dep_dev = dep_chan->device;
+ dep_dev->device_dependency_added(dep_chan);
+ }
+ spin_unlock_bh(&depend_tx->lock);
+ } else {
+ tx->parent = NULL;
+ chan->device->device_tx_submit(tx);
+ }
+
+ if (flags & ASYNC_TX_ACK)
+ async_tx_ack(tx);
+
+ if (depend_tx && (flags & ASYNC_TX_DEP_ACK))
+ async_tx_ack(depend_tx);
+}
+
+/**
+ * sync_epilog - actions to take if an operation is run synchronously
+ * @flags: async_tx flags
+ * @depend_tx: transaction depends on depend_tx
+ * @callback: function to call when the transaction completes
+ * @callback_param: parameter to pass to the callback routine
+ */
+static void
+sync_epilog(unsigned long flags, struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ if (callback)
+ callback(callback_param);
+
+ if (depend_tx && (flags & ASYNC_TX_DEP_ACK))
+ async_tx_ack(depend_tx);
+}
+
+static void
+do_async_xor(struct dma_async_tx_descriptor *tx, struct dma_device *device,
+ struct dma_chan *chan, struct page *dest, struct page **src_list,
+ unsigned int offset, unsigned int src_cnt, size_t len,
+ enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ dma_addr_t dma_addr;
+ enum dma_data_direction dir;
+ int i;
+
+ PRINTK("%s: len: %zu\n", __FUNCTION__, len);
+
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_FROM_DEVICE;
+
+ dma_addr = dma_map_page(device->dev, dest, offset, len, dir);
+ device->device_set_dest(dma_addr, tx, 0);
+
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_TO_DEVICE;
+
+ for (i = 0; i < src_cnt; i++) {
+ dma_addr = dma_map_page(device->dev, src_list[i],
+ offset, len, dir);
+ device->device_set_src(dma_addr, tx, i);
+ }
+
+ async_tx_submit(chan, tx, flags, depend_tx, callback,
+ callback_param);
+}
+
+static void
+do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
+ unsigned int src_cnt, size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ void *_dest;
+ int i;
+
+ PRINTK("%s: len: %zu\n", __FUNCTION__, len);
+
+ /* reuse the 'src_list' array to convert to buffer pointers */
+ for (i = 0; i < src_cnt; i++)
+ src_list[i] = (struct page *)
+ (page_address(src_list[i]) + offset);
+
+ /* set destination address */
+ _dest = page_address(dest) + offset;
+
+ if (flags & ASYNC_TX_XOR_ZERO_DST)
+ memset(_dest, 0, len);
+
+ xor_block(src_cnt, len, _dest,
+ (void **) src_list);
+
+ sync_epilog(flags, depend_tx, callback, callback_param);
+}
+
+/**
+ * async_xor - attempt to xor a set of blocks with a dma engine.
+ * xor_block 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.
+ * @dest: destination page
+ * @src_list: array of source pages (if the dest is also a source it must be
+ * at index zero). The contents of this array may be overwritten.
+ * @offset: offset in pages to start transaction
+ * @src_cnt: number of source pages
+ * @len: length in bytes
+ * @flags: ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DEST,
+ ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
+ * @depend_tx: xor depends on the result of this transaction.
+ * @callback: function to call when the xor completes
+ * @callback_param: parameter to pass to the callback routine
+ */
+struct dma_async_tx_descriptor *
+async_xor(struct page *dest, struct page **src_list, unsigned int offset,
+ unsigned int src_cnt, size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_XOR);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx = NULL;
+ dma_async_tx_callback _callback;
+ void *_callback_param;
+ unsigned long local_flags;
+ int xor_src_cnt;
+ int i = 0, src_off = 0, int_en;
+
+ BUG_ON(src_cnt <= 1);
+
+ while (src_cnt) {
+ local_flags = flags;
+ if (device) { /* run the xor asynchronously */
+ xor_src_cnt = min(src_cnt, device->max_xor);
+ /* if we are submitting additional xors
+ * only set the callback on the last transaction
+ */
+ if (src_cnt > xor_src_cnt) {
+ local_flags &= ~(ASYNC_TX_ACK | ASYNC_TX_INT_EN);
+ _callback = NULL;
+ _callback_param = NULL;
+ } else {
+ _callback = callback;
+ _callback_param = callback_param;
+ }
+
+ int_en = (local_flags & ASYNC_TX_INT_EN) ? 1 : 0;
+
+ tx = device->device_prep_dma_xor(
+ chan, xor_src_cnt, len, int_en);
+
+ if (tx) {
+ do_async_xor(tx, device, chan, dest,
+ &src_list[src_off], offset, xor_src_cnt, len,
+ local_flags, depend_tx, _callback,
+ _callback_param);
+ } else /* fall through */
+ goto xor_sync;
+ } else { /* run the xor synchronously */
+xor_sync:
+ /* in the sync case the dest is an implied source
+ * (assumes the dest is at the src_off index)
+ */
+ if (flags & ASYNC_TX_XOR_DROP_DST) {
+ src_cnt--;
+ src_off++;
+ }
+
+ /* process up to 'MAX_XOR_BLOCKS' sources */
+ xor_src_cnt = min(src_cnt, (unsigned int) MAX_XOR_BLOCKS);
+
+ /* if we are submitting additional xors
+ * only set the callback on the last transaction
+ */
+ if (src_cnt > xor_src_cnt) {
+ local_flags &= ~(ASYNC_TX_ACK | ASYNC_TX_INT_EN);
+ _callback = NULL;
+ _callback_param = NULL;
+ } else {
+ _callback = callback;
+ _callback_param = callback_param;
+ }
+
+ /* wait for any prerequisite operations */
+ if (depend_tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+ if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for depend_tx\n",
+ __FUNCTION__);
+ }
+
+ do_sync_xor(dest, &src_list[src_off], offset,
+ xor_src_cnt, len, local_flags, depend_tx,
+ _callback, _callback_param);
+ }
+
+ /* the previous tx is hidden from the client,
+ * so ack it
+ */
+ if (i && depend_tx)
+ async_tx_ack(depend_tx);
+
+ depend_tx = tx;
+
+ if (src_cnt > xor_src_cnt) {
+ /* drop completed sources */
+ src_cnt -= xor_src_cnt;
+ src_off += xor_src_cnt;
+
+ /* unconditionally preserve the destination */
+ flags &= ~ASYNC_TX_XOR_ZERO_DST;
+
+ /* use the intermediate result a source, but remember
+ * it's dropped, because it's implied, in the sync case
+ */
+ src_list[--src_off] = dest;
+ src_cnt++;
+ flags |= ASYNC_TX_XOR_DROP_DST;
+ } else
+ src_cnt = 0;
+ i++;
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_xor);
+
+static int page_is_zero(struct page *p, size_t len)
+{
+ char *a = page_address(p);
+ return ((*(u32*)a) == 0 &&
+ memcmp(a, a+4, len-4)==0);
+}
+
+/**
+ * async_xor_zero_sum - 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. The dest page must be listed as a source
+ * at index zero. The contents of this array may be overwritten.
+ * @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
+ * @flags: ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK
+ * @depend_tx: xor depends on the result of this transaction.
+ * @callback: function to call when the xor completes
+ * @callback_param: parameter to pass to the callback routine
+ */
+struct dma_async_tx_descriptor *
+async_xor_zero_sum(struct page *dest, struct page **src_list,
+ unsigned int offset, unsigned int src_cnt, size_t len,
+ u32 *result, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_ZERO_SUM);
+ struct dma_device *device = chan ? chan->device : NULL;
+ int int_en = (flags & ASYNC_TX_INT_EN) ? 1 : 0;
+ struct dma_async_tx_descriptor *tx = device ?
+ device->device_prep_dma_zero_sum(chan, src_cnt, len, result,
+ int_en) : NULL;
+ int i;
+
+ if (tx) {
+ dma_addr_t dma_addr;
+ enum dma_data_direction dir;
+
+ PRINTK("%s: (async) len: %zu\n", __FUNCTION__, len);
+
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_TO_DEVICE;
+
+ for (i = 0; i < src_cnt; i++) {
+ dma_addr = dma_map_page(device->dev, src_list[i],
+ offset, len, dir);
+ device->device_set_src(dma_addr, tx, i);
+ }
+
+ async_tx_submit(chan, tx, flags, depend_tx, callback,
+ callback_param);
+ } else {
+ unsigned long xor_flags = flags;
+
+ PRINTK("%s: (sync) len: %zu\n", __FUNCTION__, len);
+
+ xor_flags |= ASYNC_TX_XOR_DROP_DST;
+ xor_flags &= ~ASYNC_TX_ACK;
+
+ tx = async_xor(dest, src_list, offset, src_cnt, len, xor_flags,
+ depend_tx, NULL, NULL);
+
+ if (tx) {
+ if (dma_wait_for_async_tx(tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for tx\n",
+ __FUNCTION__);
+ async_tx_ack(tx);
+ }
+
+ *result = page_is_zero(dest, len) ? 0 : 1;
+
+ tx = NULL;
+
+ sync_epilog(flags, depend_tx, callback, callback_param);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_xor_zero_sum);
+
+/**
+ * async_memcpy - attempt to copy memory with a dma engine.
+ * @dest: destination page
+ * @src: src page
+ * @offset: offset in pages to start transaction
+ * @len: length in bytes
+ * @flags: ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK, ASYNC_TX_DEP_ACK,
+ * ASYNC_TX_KMAP_SRC, ASYNC_TX_KMAP_DST
+ * @depend_tx: memcpy depends on the result of this transaction
+ * @callback: function to call when the memcpy completes
+ * @callback_param: parameter to pass to the callback routine
+ */
+struct dma_async_tx_descriptor *
+async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
+ unsigned int src_offset, size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_MEMCPY);
+ struct dma_device *device = chan ? chan->device : NULL;
+ int int_en = (flags & ASYNC_TX_INT_EN) ? 1 : 0;
+ struct dma_async_tx_descriptor *tx = device ?
+ device->device_prep_dma_memcpy(chan, len,
+ int_en) : NULL;
+
+ if (tx) { /* run the memcpy asynchronously */
+ dma_addr_t dma_addr;
+ enum dma_data_direction dir;
+
+ PRINTK("%s: (async) len: %zu\n", __FUNCTION__, len);
+
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_FROM_DEVICE;
+
+ dma_addr = dma_map_page(device->dev, dest, dest_offset, len, dir);
+ device->device_set_dest(dma_addr, tx, 0);
+
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_TO_DEVICE;
+
+ dma_addr = dma_map_page(device->dev, src, src_offset, len, dir);
+ device->device_set_src(dma_addr, tx, 0);
+
+ async_tx_submit(chan, tx, flags, depend_tx, callback,
+ callback_param);
+ } else { /* run the memcpy synchronously */
+ void *dest_buf, *src_buf;
+ PRINTK("%s: (sync) len: %zu\n", __FUNCTION__, len);
+
+ /* wait for any prerequisite operations */
+ if (depend_tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+ if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for depend_tx\n",
+ __FUNCTION__);
+ }
+
+ if (flags & ASYNC_TX_KMAP_DST)
+ dest_buf = kmap_atomic(dest, KM_USER0) + dest_offset;
+ else
+ dest_buf = page_address(dest) + dest_offset;
+
+ if (flags & ASYNC_TX_KMAP_SRC)
+ src_buf = kmap_atomic(src, KM_USER0) + src_offset;
+ else
+ src_buf = page_address(src) + src_offset;
+
+ memcpy(dest_buf, src_buf, len);
+
+ if (flags & ASYNC_TX_KMAP_DST)
+ kunmap_atomic(dest_buf, KM_USER0);
+
+ if (flags & ASYNC_TX_KMAP_SRC)
+ kunmap_atomic(src_buf, KM_USER0);
+
+ sync_epilog(flags, depend_tx, callback, callback_param);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_memcpy);
+
+/**
+ * async_memset - attempt to fill memory with a dma engine.
+ * @dest: destination page
+ * @val: fill value
+ * @offset: offset in pages to start transaction
+ * @len: length in bytes
+ * @flags: ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK
+ * @depend_tx: memset depends on the result of this transaction
+ * @callback: function to call when the memcpy completes
+ * @callback_param: parameter to pass to the callback routine
+ */
+struct dma_async_tx_descriptor *
+async_memset(struct page *dest, int val, unsigned int offset,
+ size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_MEMSET);
+ struct dma_device *device = chan ? chan->device : NULL;
+ int int_en = (flags & ASYNC_TX_INT_EN) ? 1 : 0;
+ struct dma_async_tx_descriptor *tx = device ?
+ device->device_prep_dma_memset(chan, val, len,
+ int_en) : NULL;
+
+ if (tx) { /* run the memset asynchronously */
+ dma_addr_t dma_addr;
+ enum dma_data_direction dir;
+
+ PRINTK("%s: (async) len: %zu\n", __FUNCTION__, len);
+ dir = (flags & ASYNC_TX_ASSUME_COHERENT) ?
+ DMA_NONE : DMA_FROM_DEVICE;
+
+ dma_addr = dma_map_page(device->dev, dest, offset, len, dir);
+ device->device_set_dest(dma_addr, tx, 0);
+
+ async_tx_submit(chan, tx, flags, depend_tx, callback,
+ callback_param);
+ } else { /* run the memset synchronously */
+ void *dest_buf;
+ PRINTK("%s: (sync) len: %zu\n", __FUNCTION__, len);
+
+ dest_buf = (void *) (((char *) page_address(dest)) + offset);
+
+ /* wait for any prerequisite operations */
+ if (depend_tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+ if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for depend_tx\n",
+ __FUNCTION__);
+ }
+
+ memset(dest_buf, val, len);
+
+ sync_epilog(flags, depend_tx, callback, callback_param);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_memset);
+
+/**
+ * async_interrupt - cause an interrupt to asynchrounously flush pending
+ * completion callbacks, or schedule new callback. Note: this rouine
+ * assumes that all dma channels have the DMA_INTERRUPT capability
+ * @flags: ASYNC_TX_DEP_ACK
+ * @depend_tx: interrupt depends the result of this transaction
+ * @callback: function to call after the interrupt fires
+ * @callback_param: parameter to pass to the callback routine
+ */
+struct dma_async_tx_descriptor *
+async_interrupt(enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param)
+{
+ struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_INTERRUPT);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx = device ?
+ device->device_prep_dma_interrupt(chan) : NULL;
+
+ if (tx) {
+ PRINTK("%s: (async)\n", __FUNCTION__);
+
+ async_tx_submit(chan, tx, flags, depend_tx, callback,
+ callback_param);
+ } else {
+ PRINTK("%s: (sync)\n", __FUNCTION__);
+
+ /* wait for any prerequisite operations */
+ if (depend_tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+ if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for depend_tx\n",
+ __FUNCTION__);
+ }
+
+ sync_epilog(flags, depend_tx, callback, callback_param);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_interrupt);
+
+/**
+ * async_interrupt_cond - same as async_interrupt except that this will only be
+ * if next_op must be run on a different channel. Note: this rouine
+ * assumes that all dma channels have the DMA_INTERRUPT capability
+ * @next_op: the next operation type to be submitted
+ * @flags: ASYNC_TX_DEP_ACK
+ * @depend_tx: interrupt depends the result of this transaction
+ */
+struct dma_async_tx_descriptor *
+async_interrupt_cond(enum dma_transaction_type next_op,
+ enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx)
+{
+ int chan_switch = depend_tx ?
+ !test_bit(next_op, &depend_tx->chan->device->capabilities) : 0;
+ struct dma_chan *chan = chan_switch ? depend_tx->chan : NULL;
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx = device ?
+ device->device_prep_dma_interrupt(chan) : NULL;
+
+ if (!chan_switch)
+ return depend_tx;
+ else if (tx) {
+ PRINTK("%s: (async)\n", __FUNCTION__);
+
+ async_tx_submit(chan, tx, flags, depend_tx, NULL, NULL);
+ } else {
+ PRINTK("%s: (sync)\n", __FUNCTION__);
+
+ /* wait for any prerequisite operations */
+ if (depend_tx) {
+ /* if ack is already set then we cannot be sure
+ * we are referring to the correct operation
+ */
+ BUG_ON(depend_tx->ack);
+ if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+ panic("%s: DMA_ERROR waiting for depend_tx\n",
+ __FUNCTION__);
+ }
+
+ sync_epilog(flags, depend_tx, NULL, NULL);
+ }
+
+ return tx;
+}
+EXPORT_SYMBOL_GPL(async_interrupt_cond);
+
+module_init(async_tx_init);
+module_exit(async_tx_exit);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Asynchronous Bulk Memory Transactions API");
+MODULE_LICENSE("GPL");
diff --git a/drivers/dma/xor.c b/drivers/dma/xor.c
new file mode 100644
index 0000000..6eb3416
--- /dev/null
+++ b/drivers/dma/xor.c
@@ -0,0 +1,153 @@
+/*
+ * xor.c : Multiple Devices driver for Linux
+ *
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000,
+ * Ingo Molnar, Matti Aarnio, Jakub Jelinek, Richard Henderson.
+ *
+ * Dispatch optimized RAID-5 checksumming functions.
+ *
+ * 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, or (at your option)
+ * any later version.
+ *
+ * You should have received a copy of the GNU General Public License
+ * (for example /usr/src/linux/COPYING); if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define BH_TRACE 0
+#include <linux/module.h>
+#include <linux/raid/md.h>
+#include <linux/raid/xor.h>
+#include <asm/xor.h>
+
+/* The xor routines to use. */
+static struct xor_block_template *active_template;
+
+void
+xor_block(unsigned int src_count, unsigned int bytes, void *dest, void **srcs)
+{
+ unsigned long *p1, *p2, *p3, *p4;
+
+ p1 = (unsigned long *) srcs[0];
+ if (src_count == 1) {
+ active_template->do_2(bytes, dest, p1);
+ return;
+ }
+
+ p2 = (unsigned long *) srcs[1];
+ if (src_count == 2) {
+ active_template->do_3(bytes, dest, p1, p2);
+ return;
+ }
+
+ p3 = (unsigned long *) srcs[2];
+ if (src_count == 3) {
+ active_template->do_4(bytes, dest, p1, p2, p3);
+ return;
+ }
+
+ p4 = (unsigned long *) srcs[3];
+ active_template->do_5(bytes, dest, p1, p2, p3, p4);
+}
+
+/* Set of all registered templates. */
+static struct xor_block_template *template_list;
+
+#define BENCH_SIZE (PAGE_SIZE)
+
+static void
+do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
+{
+ int speed;
+ unsigned long now;
+ int i, count, max;
+
+ tmpl->next = template_list;
+ template_list = tmpl;
+
+ /*
+ * Count the number of XORs done during a whole jiffy, and use
+ * this to calculate the speed of checksumming. We use a 2-page
+ * allocation to have guaranteed color L1-cache layout.
+ */
+ max = 0;
+ for (i = 0; i < 5; i++) {
+ now = jiffies;
+ count = 0;
+ while (jiffies == now) {
+ mb();
+ tmpl->do_2(BENCH_SIZE, b1, b2);
+ mb();
+ count++;
+ mb();
+ }
+ if (count > max)
+ max = count;
+ }
+
+ speed = max * (HZ * BENCH_SIZE / 1024);
+ tmpl->speed = speed;
+
+ printk(" %-10s: %5d.%03d MB/sec\n", tmpl->name,
+ speed / 1000, speed % 1000);
+}
+
+static int
+calibrate_xor_block(void)
+{
+ void *b1, *b2;
+ struct xor_block_template *f, *fastest;
+
+ b1 = (void *) __get_free_pages(GFP_KERNEL, 2);
+ if (! b1) {
+ printk("xor: Yikes! No memory available.\n");
+ return -ENOMEM;
+ }
+ b2 = b1 + 2*PAGE_SIZE + BENCH_SIZE;
+
+ /*
+ * If this arch/cpu has a short-circuited selection, don't loop through all
+ * the possible functions, just test the best one
+ */
+
+ fastest = NULL;
+
+#ifdef XOR_SELECT_TEMPLATE
+ fastest = XOR_SELECT_TEMPLATE(fastest);
+#endif
+
+#define xor_speed(templ) do_xor_speed((templ), b1, b2)
+
+ if (fastest) {
+ printk(KERN_INFO "xor: automatically using best checksumming function: %s\n",
+ fastest->name);
+ xor_speed(fastest);
+ } else {
+ printk(KERN_INFO "xor: measuring software checksumming speed\n");
+ XOR_TRY_TEMPLATES;
+ fastest = template_list;
+ for (f = fastest; f; f = f->next)
+ if (f->speed > fastest->speed)
+ fastest = f;
+ }
+
+ printk("xor: using function: %s (%d.%03d MB/sec)\n",
+ fastest->name, fastest->speed / 1000, fastest->speed % 1000);
+
+#undef xor_speed
+
+ free_pages((unsigned long)b1, 2);
+
+ active_template = fastest;
+ return 0;
+}
+
+static __exit void xor_exit(void) { }
+
+EXPORT_SYMBOL(xor_block);
+MODULE_LICENSE("GPL");
+
+module_init(calibrate_xor_block);
+module_exit(xor_exit);
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 4540ade..79a361e 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -8,6 +8,7 @@ menu "Multi-device support (RAID and LVM)"
config MD
bool "Multiple devices driver support (RAID and LVM)"
+ select ASYNC_TX_DMA
help
Support multiple physical spindles through a single logical device.
Required for RAID and logical volume management.
@@ -108,7 +109,7 @@ config MD_RAID10
config MD_RAID456
tristate "RAID-4/RAID-5/RAID-6 mode"
- depends on BLK_DEV_MD
+ depends on BLK_DEV_MD && ASYNC_TX_DMA
---help---
A RAID-5 set of N drives with a capacity of C MB per drive provides
the capacity of C * (N - 1) MB, and protects against a failure
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 34957a6..23c3049 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -17,15 +17,15 @@ raid456-objs := raid5.o raid6algos.o raid6recov.o raid6tables.o \
hostprogs-y := mktables
# Note: link order is important. All raid personalities
-# and xor.o must come before md.o, as they each initialise
-# themselves, and md.o may use the personalities when it
+# must come before md.o, as they each initialise
+# themselves, and md.o may use the personalities when it
# auto-initialised.
obj-$(CONFIG_MD_LINEAR) += linear.o
obj-$(CONFIG_MD_RAID0) += raid0.o
obj-$(CONFIG_MD_RAID1) += raid1.o
obj-$(CONFIG_MD_RAID10) += raid10.o
-obj-$(CONFIG_MD_RAID456) += raid456.o xor.o
+obj-$(CONFIG_MD_RAID456) += raid456.o
obj-$(CONFIG_MD_MULTIPATH) += multipath.o
obj-$(CONFIG_MD_FAULTY) += faulty.o
obj-$(CONFIG_BLK_DEV_MD) += md-mod.o
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 54a1ad5..6386814 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -916,25 +916,25 @@ static void copy_data(int frombio, struct bio *bio,
}
}
-#define check_xor() do { \
- if (count == MAX_XOR_BLOCKS) { \
- xor_block(count, STRIPE_SIZE, ptr); \
- count = 1; \
- } \
+#define check_xor() do { \
+ if (count == MAX_XOR_BLOCKS) { \
+ xor_block(count, STRIPE_SIZE, dest, ptr); \
+ count = 0; \
+ } \
} while(0)
static void compute_block(struct stripe_head *sh, int dd_idx)
{
int i, count, disks = sh->disks;
- void *ptr[MAX_XOR_BLOCKS], *p;
+ void *ptr[MAX_XOR_BLOCKS], *dest, *p;
PRINTK("compute_block, stripe %llu, idx %d\n",
(unsigned long long)sh->sector, dd_idx);
- ptr[0] = page_address(sh->dev[dd_idx].page);
- memset(ptr[0], 0, STRIPE_SIZE);
- count = 1;
+ dest = page_address(sh->dev[dd_idx].page);
+ memset(dest, 0, STRIPE_SIZE);
+ count = 0;
for (i = disks ; i--; ) {
if (i == dd_idx)
continue;
@@ -948,8 +948,8 @@ static void compute_block(struct stripe_head *sh, int dd_idx)
check_xor();
}
- if (count != 1)
- xor_block(count, STRIPE_SIZE, ptr);
+ if (count)
+ xor_block(count, STRIPE_SIZE, dest, ptr);
set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
}
@@ -957,14 +957,14 @@ static void compute_parity5(struct stripe_head *sh, int method)
{
raid5_conf_t *conf = sh->raid_conf;
int i, pd_idx = sh->pd_idx, disks = sh->disks, count;
- void *ptr[MAX_XOR_BLOCKS];
+ void *ptr[MAX_XOR_BLOCKS], *dest;
struct bio *chosen;
PRINTK("compute_parity5, stripe %llu, method %d\n",
(unsigned long long)sh->sector, method);
- count = 1;
- ptr[0] = page_address(sh->dev[pd_idx].page);
+ count = 0;
+ dest = page_address(sh->dev[pd_idx].page);
switch(method) {
case READ_MODIFY_WRITE:
BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags));
@@ -987,7 +987,7 @@ static void compute_parity5(struct stripe_head *sh, int method)
}
break;
case RECONSTRUCT_WRITE:
- memset(ptr[0], 0, STRIPE_SIZE);
+ memset(dest, 0, STRIPE_SIZE);
for (i= disks; i-- ;)
if (i!=pd_idx && sh->dev[i].towrite) {
chosen = sh->dev[i].towrite;
@@ -1003,9 +1003,9 @@ static void compute_parity5(struct stripe_head *sh, int method)
case CHECK_PARITY:
break;
}
- if (count>1) {
- xor_block(count, STRIPE_SIZE, ptr);
- count = 1;
+ if (count) {
+ xor_block(count, STRIPE_SIZE, dest, ptr);
+ count = 0;
}
for (i = disks; i--;)
@@ -1037,8 +1037,8 @@ static void compute_parity5(struct stripe_head *sh, int method)
check_xor();
}
}
- if (count != 1)
- xor_block(count, STRIPE_SIZE, ptr);
+ if (count)
+ xor_block(count, STRIPE_SIZE, dest, ptr);
if (method != CHECK_PARITY) {
set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
@@ -1132,7 +1132,7 @@ static void compute_parity6(struct stripe_head *sh, int method)
static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
{
int i, count, disks = sh->disks;
- void *ptr[MAX_XOR_BLOCKS], *p;
+ void *ptr[MAX_XOR_BLOCKS], *dest, *p;
int pd_idx = sh->pd_idx;
int qd_idx = raid6_next_disk(pd_idx, disks);
@@ -1143,9 +1143,9 @@ static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
/* We're actually computing the Q drive */
compute_parity6(sh, UPDATE_PARITY);
} else {
- ptr[0] = page_address(sh->dev[dd_idx].page);
- if (!nozero) memset(ptr[0], 0, STRIPE_SIZE);
- count = 1;
+ dest = page_address(sh->dev[dd_idx].page);
+ if (!nozero) memset(dest, 0, STRIPE_SIZE);
+ count = 0;
for (i = disks ; i--; ) {
if (i == dd_idx || i == qd_idx)
continue;
@@ -1159,8 +1159,8 @@ static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero)
check_xor();
}
- if (count != 1)
- xor_block(count, STRIPE_SIZE, ptr);
+ if (count)
+ xor_block(count, STRIPE_SIZE, dest, ptr);
if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags);
}
diff --git a/drivers/md/xor.c b/drivers/md/xor.c
deleted file mode 100644
index 324897c..0000000
--- a/drivers/md/xor.c
+++ /dev/null
@@ -1,154 +0,0 @@
-/*
- * xor.c : Multiple Devices driver for Linux
- *
- * Copyright (C) 1996, 1997, 1998, 1999, 2000,
- * Ingo Molnar, Matti Aarnio, Jakub Jelinek, Richard Henderson.
- *
- * Dispatch optimized RAID-5 checksumming functions.
- *
- * 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, or (at your option)
- * any later version.
- *
- * You should have received a copy of the GNU General Public License
- * (for example /usr/src/linux/COPYING); if not, write to the Free
- * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#define BH_TRACE 0
-#include <linux/module.h>
-#include <linux/raid/md.h>
-#include <linux/raid/xor.h>
-#include <asm/xor.h>
-
-/* The xor routines to use. */
-static struct xor_block_template *active_template;
-
-void
-xor_block(unsigned int count, unsigned int bytes, void **ptr)
-{
- unsigned long *p0, *p1, *p2, *p3, *p4;
-
- p0 = (unsigned long *) ptr[0];
- p1 = (unsigned long *) ptr[1];
- if (count == 2) {
- active_template->do_2(bytes, p0, p1);
- return;
- }
-
- p2 = (unsigned long *) ptr[2];
- if (count == 3) {
- active_template->do_3(bytes, p0, p1, p2);
- return;
- }
-
- p3 = (unsigned long *) ptr[3];
- if (count == 4) {
- active_template->do_4(bytes, p0, p1, p2, p3);
- return;
- }
-
- p4 = (unsigned long *) ptr[4];
- active_template->do_5(bytes, p0, p1, p2, p3, p4);
-}
-
-/* Set of all registered templates. */
-static struct xor_block_template *template_list;
-
-#define BENCH_SIZE (PAGE_SIZE)
-
-static void
-do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2)
-{
- int speed;
- unsigned long now;
- int i, count, max;
-
- tmpl->next = template_list;
- template_list = tmpl;
-
- /*
- * Count the number of XORs done during a whole jiffy, and use
- * this to calculate the speed of checksumming. We use a 2-page
- * allocation to have guaranteed color L1-cache layout.
- */
- max = 0;
- for (i = 0; i < 5; i++) {
- now = jiffies;
- count = 0;
- while (jiffies == now) {
- mb();
- tmpl->do_2(BENCH_SIZE, b1, b2);
- mb();
- count++;
- mb();
- }
- if (count > max)
- max = count;
- }
-
- speed = max * (HZ * BENCH_SIZE / 1024);
- tmpl->speed = speed;
-
- printk(" %-10s: %5d.%03d MB/sec\n", tmpl->name,
- speed / 1000, speed % 1000);
-}
-
-static int
-calibrate_xor_block(void)
-{
- void *b1, *b2;
- struct xor_block_template *f, *fastest;
-
- b1 = (void *) __get_free_pages(GFP_KERNEL, 2);
- if (! b1) {
- printk("raid5: Yikes! No memory available.\n");
- return -ENOMEM;
- }
- b2 = b1 + 2*PAGE_SIZE + BENCH_SIZE;
-
- /*
- * If this arch/cpu has a short-circuited selection, don't loop through all
- * the possible functions, just test the best one
- */
-
- fastest = NULL;
-
-#ifdef XOR_SELECT_TEMPLATE
- fastest = XOR_SELECT_TEMPLATE(fastest);
-#endif
-
-#define xor_speed(templ) do_xor_speed((templ), b1, b2)
-
- if (fastest) {
- printk(KERN_INFO "raid5: automatically using best checksumming function: %s\n",
- fastest->name);
- xor_speed(fastest);
- } else {
- printk(KERN_INFO "raid5: measuring checksumming speed\n");
- XOR_TRY_TEMPLATES;
- fastest = template_list;
- for (f = fastest; f; f = f->next)
- if (f->speed > fastest->speed)
- fastest = f;
- }
-
- printk("raid5: using function: %s (%d.%03d MB/sec)\n",
- fastest->name, fastest->speed / 1000, fastest->speed % 1000);
-
-#undef xor_speed
-
- free_pages((unsigned long)b1, 2);
-
- active_template = fastest;
- return 0;
-}
-
-static __exit void xor_exit(void) { }
-
-EXPORT_SYMBOL(xor_block);
-MODULE_LICENSE("GPL");
-
-module_init(calibrate_xor_block);
-module_exit(xor_exit);
diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h
new file mode 100644
index 0000000..302c4f6
--- /dev/null
+++ b/include/linux/async_tx.h
@@ -0,0 +1,180 @@
+/*
+ * Copyright(c) 2006 Intel Corporation. All rights reserved.
+ *
+ * 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/dmaengine.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+
+struct dma_chan_ref {
+ struct dma_chan *chan;
+ struct list_head async_node;
+ struct rcu_head rcu;
+};
+
+struct async_iter_percpu {
+ struct list_head *iter;
+ unsigned long local_version;
+};
+
+struct async_channel_entry {
+ struct list_head list;
+ spinlock_t lock;
+ struct async_iter_percpu *local_iter;
+ atomic_t version;
+};
+
+/**
+ * async_tx_flags - modifiers for the async_* calls
+ * @ASYNC_TX_XOR_ZERO_DST: for synchronous xor: zero the destination
+ * asynchronous assumes a pre-zeroed destination
+ * @ASYNC_TX_XOR_DROP_DST: for synchronous xor: drop source index zero (dest)
+ * the dest is an implicit source to the synchronous routine
+ * @ASYNC_TX_ASSUME_COHERENT: skip cache maintenance operations
+ * @ASYNC_TX_ACK: immediately ack the descriptor, preclude setting up a
+ * dependency chain
+ * @ASYNC_TX_DEP_ACK: ack the dependency
+ * @ASYNC_TX_INT_EN: have the dma engine trigger an interrupt on completion
+ * @ASYNC_TX_KMAP_SRC: take an atomic mapping (KM_USER0) on the source page(s)
+ * if the transaction is to be performed synchronously
+ * @ASYNC_TX_KMAP_DST: take an atomic mapping (KM_USER0) on the dest page(s)
+ * if the transaction is to be performed synchronously
+ */
+enum async_tx_flags {
+ ASYNC_TX_XOR_ZERO_DST = (1 << 0),
+ ASYNC_TX_XOR_DROP_DST = (1 << 1),
+ ASYNC_TX_ASSUME_COHERENT = (1 << 2),
+ ASYNC_TX_ACK = (1 << 3),
+ ASYNC_TX_DEP_ACK = (1 << 4),
+ ASYNC_TX_INT_EN = (1 << 5),
+ ASYNC_TX_KMAP_SRC = (1 << 6),
+ ASYNC_TX_KMAP_DST = (1 << 7),
+};
+
+#ifdef CONFIG_DMA_ENGINE
+static inline enum dma_status
+dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
+{
+ enum dma_status status;
+ struct dma_async_tx_descriptor *iter;
+
+ if (!tx)
+ return DMA_SUCCESS;
+
+ /* poll through the dependency chain, return when tx is complete */
+ do {
+ iter = tx;
+ while (iter->cookie == -EBUSY)
+ iter = iter->parent;
+
+ status = dma_sync_wait(iter->chan, iter->cookie);
+ } while (status == DMA_IN_PROGRESS || (iter != tx));
+
+ return status;
+}
+
+extern struct async_channel_entry async_tx_master_list;
+static inline void async_tx_issue_pending_all(void)
+{
+ struct dma_chan_ref *ref;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ref, &async_tx_master_list.list, async_node)
+ ref->chan->device->device_issue_pending(ref->chan);
+ rcu_read_unlock();
+}
+
+static inline void
+async_tx_run_dependencies(struct dma_async_tx_descriptor *tx,
+ struct dma_chan *host_chan)
+{
+ struct dma_async_tx_descriptor *dep_tx, *_dep_tx;
+ struct dma_device *dev;
+ struct dma_chan *chan;
+
+ list_for_each_entry_safe(dep_tx, _dep_tx, &tx->depend_list,
+ depend_node) {
+ chan = dep_tx->chan;
+ dev = chan->device;
+ /* we can't depend on ourselves */
+ BUG_ON(chan == host_chan);
+ list_del(&dep_tx->depend_node);
+ dev->device_tx_submit(dep_tx);
+
+ /* we need to poke the engine as client code does not
+ * know about dependency submission events
+ */
+ dev->device_issue_pending(chan);
+ }
+}
+#else
+static inline void
+async_tx_run_dependencies(struct dma_async_tx_descriptor *tx,
+ struct dma_chan *host_chan)
+{
+ do { } while (0);
+}
+
+static inline enum dma_status
+dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
+{
+ return DMA_SUCCESS;
+}
+
+static inline void async_tx_issue_pending_all(void)
+{
+ do { } while (0);
+}
+#endif
+
+static inline void
+async_tx_ack(struct dma_async_tx_descriptor *tx)
+{
+ tx->ack = 1;
+}
+
+struct dma_async_tx_descriptor *
+async_xor(struct page *dest, struct page **src_list, unsigned int offset,
+ unsigned int src_cnt, size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param);
+struct dma_async_tx_descriptor *
+async_xor_zero_sum(struct page *dest, struct page **src_list,
+ unsigned int offset, unsigned int src_cnt, size_t len,
+ u32 *result, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param);
+struct dma_async_tx_descriptor *
+async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
+ unsigned int src_offset, size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param);
+struct dma_async_tx_descriptor *
+async_memset(struct page *dest, int val, unsigned int offset,
+ size_t len, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param);
+struct dma_async_tx_descriptor *
+async_interrupt(enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx,
+ dma_async_tx_callback callback, void *callback_param);
+struct dma_async_tx_descriptor *
+async_interrupt_cond(enum dma_transaction_type next_op,
+ enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *depend_tx);
diff --git a/include/linux/raid/xor.h b/include/linux/raid/xor.h
index f0d67cb..d151f16 100644
--- a/include/linux/raid/xor.h
+++ b/include/linux/raid/xor.h
@@ -3,9 +3,10 @@
#include <linux/raid/md.h>
-#define MAX_XOR_BLOCKS 5
+#define MAX_XOR_BLOCKS 4
-extern void xor_block(unsigned int count, unsigned int bytes, void **ptr);
+extern void xor_block(unsigned int count, unsigned int bytes,
+ void *dest, void **srcs);
struct xor_block_template {
struct xor_block_template *next;
-
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