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-rw-r--r--Documentation/crypto/async-tx-api.txt75
-rw-r--r--arch/arm/include/asm/hardware/iop3xx-adma.h5
-rw-r--r--arch/arm/mach-iop13xx/include/mach/adma.h12
-rw-r--r--arch/arm/mach-iop13xx/setup.c10
-rw-r--r--arch/arm/plat-iop/adma.c2
-rw-r--r--crypto/async_tx/Kconfig9
-rw-r--r--crypto/async_tx/Makefile3
-rw-r--r--crypto/async_tx/async_memcpy.c39
-rw-r--r--crypto/async_tx/async_memset.c38
-rw-r--r--crypto/async_tx/async_pq.c388
-rw-r--r--crypto/async_tx/async_raid6_recov.c448
-rw-r--r--crypto/async_tx/async_tx.c83
-rw-r--r--crypto/async_tx/async_xor.c199
-rw-r--r--crypto/async_tx/raid6test.c241
-rw-r--r--drivers/dma/Kconfig2
-rw-r--r--drivers/dma/dmaengine.c53
-rw-r--r--drivers/dma/dmatest.c26
-rw-r--r--drivers/dma/iop-adma.c40
-rw-r--r--drivers/md/Kconfig26
-rw-r--r--drivers/md/raid5.c1486
-rw-r--r--drivers/md/raid5.h28
-rw-r--r--include/linux/async_tx.h126
-rw-r--r--include/linux/dmaengine.h116
23 files changed, 2528 insertions, 927 deletions
diff --git a/Documentation/crypto/async-tx-api.txt b/Documentation/crypto/async-tx-api.txt
index 9f59fcb..ba046b8 100644
--- a/Documentation/crypto/async-tx-api.txt
+++ b/Documentation/crypto/async-tx-api.txt
@@ -54,20 +54,23 @@ features surfaced as a result:
3.1 General format of the API:
struct dma_async_tx_descriptor *
-async_<operation>(<op specific parameters>,
- enum async_tx_flags flags,
- struct dma_async_tx_descriptor *dependency,
- dma_async_tx_callback callback_routine,
- void *callback_parameter);
+async_<operation>(<op specific parameters>, struct async_submit ctl *submit)
3.2 Supported operations:
-memcpy - memory copy between a source and a destination buffer
-memset - fill a destination buffer with a byte value
-xor - xor a series of source buffers and write the result to a
- destination buffer
-xor_zero_sum - xor a series of source buffers and set a flag if the
- result is zero. The implementation attempts to prevent
- writes to memory
+memcpy - memory copy between a source and a destination buffer
+memset - fill a destination buffer with a byte value
+xor - xor a series of source buffers and write the result to a
+ destination buffer
+xor_val - xor a series of source buffers and set a flag if the
+ result is zero. The implementation attempts to prevent
+ writes to memory
+pq - generate the p+q (raid6 syndrome) from a series of source buffers
+pq_val - validate that a p and or q buffer are in sync with a given series of
+ sources
+datap - (raid6_datap_recov) recover a raid6 data block and the p block
+ from the given sources
+2data - (raid6_2data_recov) recover 2 raid6 data blocks from the given
+ sources
3.3 Descriptor management:
The return value is non-NULL and points to a 'descriptor' when the operation
@@ -80,8 +83,8 @@ acknowledged by the application before the offload engine driver is allowed to
recycle (or free) the descriptor. A descriptor can be acked by one of the
following methods:
1/ setting the ASYNC_TX_ACK flag if no child operations are to be submitted
-2/ setting the ASYNC_TX_DEP_ACK flag to acknowledge the parent
- descriptor of a new operation.
+2/ submitting an unacknowledged descriptor as a dependency to another
+ async_tx call will implicitly set the acknowledged state.
3/ calling async_tx_ack() on the descriptor.
3.4 When does the operation execute?
@@ -119,30 +122,42 @@ of an operation.
Perform a xor->copy->xor operation where each operation depends on the
result from the previous operation:
-void complete_xor_copy_xor(void *param)
+void callback(void *param)
{
- printk("complete\n");
+ struct completion *cmp = param;
+
+ complete(cmp);
}
-int run_xor_copy_xor(struct page **xor_srcs,
- int xor_src_cnt,
- struct page *xor_dest,
- size_t xor_len,
- struct page *copy_src,
- struct page *copy_dest,
- size_t copy_len)
+void run_xor_copy_xor(struct page **xor_srcs,
+ int xor_src_cnt,
+ struct page *xor_dest,
+ size_t xor_len,
+ struct page *copy_src,
+ struct page *copy_dest,
+ size_t copy_len)
{
struct dma_async_tx_descriptor *tx;
+ addr_conv_t addr_conv[xor_src_cnt];
+ struct async_submit_ctl submit;
+ addr_conv_t addr_conv[NDISKS];
+ struct completion cmp;
+
+ init_async_submit(&submit, ASYNC_TX_XOR_DROP_DST, NULL, NULL, NULL,
+ addr_conv);
+ tx = async_xor(xor_dest, xor_srcs, 0, xor_src_cnt, xor_len, &submit)
- tx = async_xor(xor_dest, xor_srcs, 0, xor_src_cnt, xor_len,
- ASYNC_TX_XOR_DROP_DST, NULL, NULL, NULL);
- tx = async_memcpy(copy_dest, copy_src, 0, 0, copy_len,
- ASYNC_TX_DEP_ACK, tx, NULL, NULL);
- tx = async_xor(xor_dest, xor_srcs, 0, xor_src_cnt, xor_len,
- ASYNC_TX_XOR_DROP_DST | ASYNC_TX_DEP_ACK | ASYNC_TX_ACK,
- tx, complete_xor_copy_xor, NULL);
+ submit->depend_tx = tx;
+ tx = async_memcpy(copy_dest, copy_src, 0, 0, copy_len, &submit);
+
+ init_completion(&cmp);
+ init_async_submit(&submit, ASYNC_TX_XOR_DROP_DST | ASYNC_TX_ACK, tx,
+ callback, &cmp, addr_conv);
+ tx = async_xor(xor_dest, xor_srcs, 0, xor_src_cnt, xor_len, &submit);
async_tx_issue_pending_all();
+
+ wait_for_completion(&cmp);
}
See include/linux/async_tx.h for more information on the flags. See the
diff --git a/arch/arm/include/asm/hardware/iop3xx-adma.h b/arch/arm/include/asm/hardware/iop3xx-adma.h
index 83e6ba3..26eefea 100644
--- a/arch/arm/include/asm/hardware/iop3xx-adma.h
+++ b/arch/arm/include/asm/hardware/iop3xx-adma.h
@@ -756,13 +756,14 @@ static inline void iop_desc_set_block_fill_val(struct iop_adma_desc_slot *desc,
hw_desc->src[0] = val;
}
-static inline int iop_desc_get_zero_result(struct iop_adma_desc_slot *desc)
+static inline enum sum_check_flags
+iop_desc_get_zero_result(struct iop_adma_desc_slot *desc)
{
struct iop3xx_desc_aau *hw_desc = desc->hw_desc;
struct iop3xx_aau_desc_ctrl desc_ctrl = hw_desc->desc_ctrl_field;
iop_paranoia(!(desc_ctrl.tx_complete && desc_ctrl.zero_result_en));
- return desc_ctrl.zero_result_err;
+ return desc_ctrl.zero_result_err << SUM_CHECK_P;
}
static inline void iop_chan_append(struct iop_adma_chan *chan)
diff --git a/arch/arm/mach-iop13xx/include/mach/adma.h b/arch/arm/mach-iop13xx/include/mach/adma.h
index 5722e86..1cd31df8 100644
--- a/arch/arm/mach-iop13xx/include/mach/adma.h
+++ b/arch/arm/mach-iop13xx/include/mach/adma.h
@@ -428,18 +428,20 @@ static inline void iop_desc_set_block_fill_val(struct iop_adma_desc_slot *desc,
hw_desc->block_fill_data = val;
}
-static inline int iop_desc_get_zero_result(struct iop_adma_desc_slot *desc)
+static inline enum sum_check_flags
+iop_desc_get_zero_result(struct iop_adma_desc_slot *desc)
{
struct iop13xx_adma_desc_hw *hw_desc = desc->hw_desc;
struct iop13xx_adma_desc_ctrl desc_ctrl = hw_desc->desc_ctrl_field;
struct iop13xx_adma_byte_count byte_count = hw_desc->byte_count_field;
+ enum sum_check_flags flags;
BUG_ON(!(byte_count.tx_complete && desc_ctrl.zero_result));
- if (desc_ctrl.pq_xfer_en)
- return byte_count.zero_result_err_q;
- else
- return byte_count.zero_result_err;
+ flags = byte_count.zero_result_err_q << SUM_CHECK_Q;
+ flags |= byte_count.zero_result_err << SUM_CHECK_P;
+
+ return flags;
}
static inline void iop_chan_append(struct iop_adma_chan *chan)
diff --git a/arch/arm/mach-iop13xx/setup.c b/arch/arm/mach-iop13xx/setup.c
index bee42c6..faaef95 100644
--- a/arch/arm/mach-iop13xx/setup.c
+++ b/arch/arm/mach-iop13xx/setup.c
@@ -478,7 +478,7 @@ void __init iop13xx_platform_init(void)
dma_cap_set(DMA_MEMCPY, plat_data->cap_mask);
dma_cap_set(DMA_XOR, plat_data->cap_mask);
dma_cap_set(DMA_DUAL_XOR, plat_data->cap_mask);
- dma_cap_set(DMA_ZERO_SUM, plat_data->cap_mask);
+ dma_cap_set(DMA_XOR_VAL, plat_data->cap_mask);
dma_cap_set(DMA_MEMSET, plat_data->cap_mask);
dma_cap_set(DMA_MEMCPY_CRC32C, plat_data->cap_mask);
dma_cap_set(DMA_INTERRUPT, plat_data->cap_mask);
@@ -490,7 +490,7 @@ void __init iop13xx_platform_init(void)
dma_cap_set(DMA_MEMCPY, plat_data->cap_mask);
dma_cap_set(DMA_XOR, plat_data->cap_mask);
dma_cap_set(DMA_DUAL_XOR, plat_data->cap_mask);
- dma_cap_set(DMA_ZERO_SUM, plat_data->cap_mask);
+ dma_cap_set(DMA_XOR_VAL, plat_data->cap_mask);
dma_cap_set(DMA_MEMSET, plat_data->cap_mask);
dma_cap_set(DMA_MEMCPY_CRC32C, plat_data->cap_mask);
dma_cap_set(DMA_INTERRUPT, plat_data->cap_mask);
@@ -502,13 +502,13 @@ void __init iop13xx_platform_init(void)
dma_cap_set(DMA_MEMCPY, plat_data->cap_mask);
dma_cap_set(DMA_XOR, plat_data->cap_mask);
dma_cap_set(DMA_DUAL_XOR, plat_data->cap_mask);
- dma_cap_set(DMA_ZERO_SUM, plat_data->cap_mask);
+ dma_cap_set(DMA_XOR_VAL, plat_data->cap_mask);
dma_cap_set(DMA_MEMSET, plat_data->cap_mask);
dma_cap_set(DMA_MEMCPY_CRC32C, plat_data->cap_mask);
dma_cap_set(DMA_INTERRUPT, plat_data->cap_mask);
- dma_cap_set(DMA_PQ_XOR, plat_data->cap_mask);
+ dma_cap_set(DMA_PQ, plat_data->cap_mask);
dma_cap_set(DMA_PQ_UPDATE, plat_data->cap_mask);
- dma_cap_set(DMA_PQ_ZERO_SUM, plat_data->cap_mask);
+ dma_cap_set(DMA_PQ_VAL, plat_data->cap_mask);
break;
}
}
diff --git a/arch/arm/plat-iop/adma.c b/arch/arm/plat-iop/adma.c
index 3c127aa..da1dd0da 100644
--- a/arch/arm/plat-iop/adma.c
+++ b/arch/arm/plat-iop/adma.c
@@ -198,7 +198,7 @@ static int __init iop3xx_adma_cap_init(void)
dma_cap_set(DMA_INTERRUPT, iop3xx_aau_data.cap_mask);
#else
dma_cap_set(DMA_XOR, iop3xx_aau_data.cap_mask);
- dma_cap_set(DMA_ZERO_SUM, iop3xx_aau_data.cap_mask);
+ dma_cap_set(DMA_XOR_VAL, iop3xx_aau_data.cap_mask);
dma_cap_set(DMA_MEMSET, iop3xx_aau_data.cap_mask);
dma_cap_set(DMA_INTERRUPT, iop3xx_aau_data.cap_mask);
#endif
diff --git a/crypto/async_tx/Kconfig b/crypto/async_tx/Kconfig
index d8fb3914..e5aeb2b 100644
--- a/crypto/async_tx/Kconfig
+++ b/crypto/async_tx/Kconfig
@@ -14,3 +14,12 @@ config ASYNC_MEMSET
tristate
select ASYNC_CORE
+config ASYNC_PQ
+ tristate
+ select ASYNC_CORE
+
+config ASYNC_RAID6_RECOV
+ tristate
+ select ASYNC_CORE
+ select ASYNC_PQ
+
diff --git a/crypto/async_tx/Makefile b/crypto/async_tx/Makefile
index 27baa7d..d1e0e6f 100644
--- a/crypto/async_tx/Makefile
+++ b/crypto/async_tx/Makefile
@@ -2,3 +2,6 @@ obj-$(CONFIG_ASYNC_CORE) += async_tx.o
obj-$(CONFIG_ASYNC_MEMCPY) += async_memcpy.o
obj-$(CONFIG_ASYNC_MEMSET) += async_memset.o
obj-$(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
index ddccfb0..98e15bd 100644
--- a/crypto/async_tx/async_memcpy.c
+++ b/crypto/async_tx/async_memcpy.c
@@ -33,28 +33,28 @@
* async_memcpy - attempt to copy memory with a dma engine.
* @dest: destination page
* @src: src page
- * @offset: offset in pages to start transaction
+ * @dest_offset: offset into 'dest' to start transaction
+ * @src_offset: offset into 'src' to start transaction
* @len: length in bytes
- * @flags: ASYNC_TX_ACK, ASYNC_TX_DEP_ACK,
- * @depend_tx: memcpy depends on the result of this transaction
- * @cb_fn: function to call when the memcpy completes
- * @cb_param: parameter to pass to the callback routine
+ * @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, enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_param)
+ unsigned int src_offset, size_t len,
+ struct async_submit_ctl *submit)
{
- struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_MEMCPY,
+ 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;
if (device) {
dma_addr_t dma_dest, dma_src;
- unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0;
+ unsigned long dma_prep_flags;
+ dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
dma_dest = dma_map_page(device->dev, dest, dest_offset, len,
DMA_FROM_DEVICE);
@@ -67,13 +67,13 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
if (tx) {
pr_debug("%s: (async) len: %zu\n", __func__, len);
- async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
+ 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(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
dest_buf = kmap_atomic(dest, KM_USER0) + dest_offset;
src_buf = kmap_atomic(src, KM_USER1) + src_offset;
@@ -83,26 +83,13 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
kunmap_atomic(dest_buf, KM_USER0);
kunmap_atomic(src_buf, KM_USER1);
- async_tx_sync_epilog(cb_fn, cb_param);
+ async_tx_sync_epilog(submit);
}
return tx;
}
EXPORT_SYMBOL_GPL(async_memcpy);
-static int __init async_memcpy_init(void)
-{
- return 0;
-}
-
-static void __exit async_memcpy_exit(void)
-{
- do { } while (0);
-}
-
-module_init(async_memcpy_init);
-module_exit(async_memcpy_exit);
-
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("asynchronous memcpy api");
MODULE_LICENSE("GPL");
diff --git a/crypto/async_tx/async_memset.c b/crypto/async_tx/async_memset.c
index 5b5eb99..b896a6e 100644
--- a/crypto/async_tx/async_memset.c
+++ b/crypto/async_tx/async_memset.c
@@ -35,26 +35,23 @@
* @val: fill value
* @offset: offset in pages to start transaction
* @len: length in bytes
- * @flags: ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
- * @depend_tx: memset depends on the result of this transaction
- * @cb_fn: function to call when the memcpy completes
- * @cb_param: parameter to pass to the callback routine
+ *
+ * honored flags: ASYNC_TX_ACK
*/
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 cb_fn, void *cb_param)
+async_memset(struct page *dest, int val, unsigned int offset, size_t len,
+ struct async_submit_ctl *submit)
{
- struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_MEMSET,
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_MEMSET,
&dest, 1, NULL, 0, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx = NULL;
if (device) {
dma_addr_t dma_dest;
- unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0;
+ unsigned long dma_prep_flags;
+ dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
dma_dest = dma_map_page(device->dev, dest, offset, len,
DMA_FROM_DEVICE);
@@ -64,38 +61,25 @@ async_memset(struct page *dest, int val, unsigned int offset,
if (tx) {
pr_debug("%s: (async) len: %zu\n", __func__, len);
- async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
+ async_tx_submit(chan, tx, submit);
} else { /* run the memset synchronously */
void *dest_buf;
pr_debug("%s: (sync) len: %zu\n", __func__, len);
- dest_buf = (void *) (((char *) page_address(dest)) + offset);
+ dest_buf = page_address(dest) + offset;
/* wait for any prerequisite operations */
- async_tx_quiesce(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
memset(dest_buf, val, len);
- async_tx_sync_epilog(cb_fn, cb_param);
+ async_tx_sync_epilog(submit);
}
return tx;
}
EXPORT_SYMBOL_GPL(async_memset);
-static int __init async_memset_init(void)
-{
- return 0;
-}
-
-static void __exit async_memset_exit(void)
-{
- do { } while (0);
-}
-
-module_init(async_memset_init);
-module_exit(async_memset_exit);
-
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("asynchronous memset 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 0000000..108b21e
--- /dev/null
+++ b/crypto/async_tx/async_pq.c
@@ -0,0 +1,388 @@
+/*
+ * 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/dma-mapping.h>
+#include <linux/raid/pq.h>
+#include <linux/async_tx.h>
+
+/**
+ * scribble - space to hold throwaway P buffer for synchronous gen_syndrome
+ */
+static struct page *scribble;
+
+static bool is_raid6_zero_block(struct page *p)
+{
+ return p == (void *) raid6_empty_zero_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, struct page **blocks,
+ const unsigned char *scfs, unsigned int offset, int disks,
+ size_t len, dma_addr_t *dma_src,
+ struct async_submit_ctl *submit)
+{
+ struct dma_async_tx_descriptor *tx = NULL;
+ struct dma_device *dma = chan->device;
+ enum dma_ctrl_flags dma_flags = 0;
+ 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 char coefs[src_cnt];
+ unsigned short pq_src_cnt;
+ dma_addr_t dma_dest[2];
+ int src_off = 0;
+ int idx;
+ int i;
+
+ /* DMAs use destinations as sources, so use BIDIRECTIONAL mapping */
+ if (P(blocks, disks))
+ dma_dest[0] = dma_map_page(dma->dev, P(blocks, disks), offset,
+ len, DMA_BIDIRECTIONAL);
+ else
+ dma_flags |= DMA_PREP_PQ_DISABLE_P;
+ if (Q(blocks, disks))
+ dma_dest[1] = dma_map_page(dma->dev, Q(blocks, disks), offset,
+ len, DMA_BIDIRECTIONAL);
+ else
+ dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+
+ /* convert source addresses being careful to collapse 'empty'
+ * sources and update the coefficients accordingly
+ */
+ for (i = 0, idx = 0; i < src_cnt; i++) {
+ if (is_raid6_zero_block(blocks[i]))
+ continue;
+ dma_src[idx] = dma_map_page(dma->dev, blocks[i], offset, len,
+ DMA_TO_DEVICE);
+ coefs[idx] = scfs[i];
+ idx++;
+ }
+ src_cnt = idx;
+
+ 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;
+ dma_flags |= DMA_COMPL_SKIP_DEST_UNMAP;
+ submit->cb_fn = NULL;
+ submit->cb_param = NULL;
+ } else {
+ dma_flags &= ~DMA_COMPL_SKIP_DEST_UNMAP;
+ submit->cb_fn = cb_fn_orig;
+ submit->cb_param = cb_param_orig;
+ if (cb_fn_orig)
+ dma_flags |= DMA_PREP_INTERRUPT;
+ }
+
+ /* Since we have clobbered the src_list we are committed
+ * to doing this asynchronously. Drivers force forward
+ * progress in case they can not provide a descriptor
+ */
+ for (;;) {
+ tx = dma->device_prep_dma_pq(chan, dma_dest,
+ &dma_src[src_off],
+ pq_src_cnt,
+ &coefs[src_off], len,
+ dma_flags);
+ if (likely(tx))
+ break;
+ async_tx_quiesce(&submit->depend_tx);
+ dma_async_issue_pending(chan);
+ }
+
+ 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;
+
+ if (submit->scribble)
+ srcs = submit->scribble;
+ else
+ srcs = (void **) blocks;
+
+ for (i = 0; i < disks; i++) {
+ if (is_raid6_zero_block(blocks[i])) {
+ BUG_ON(i > disks - 3); /* P or Q can't be zero */
+ srcs[i] = blocks[i];
+ } else
+ srcs[i] = page_address(blocks[i]) + offset;
+ }
+ 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.
+ *
+ * 'blocks' note: if submit->scribble is NULL then the contents of
+ * 'blocks' may be overridden
+ */
+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;
+ dma_addr_t *dma_src = NULL;
+
+ BUG_ON(disks > 255 || !(P(blocks, disks) || Q(blocks, disks)));
+
+ if (submit->scribble)
+ dma_src = submit->scribble;
+ else if (sizeof(dma_addr_t) <= sizeof(struct page *))
+ dma_src = (dma_addr_t *) blocks;
+
+ if (dma_src && device &&
+ (src_cnt <= dma_maxpq(device, 0) ||
+ dma_maxpq(device, DMA_PREP_CONTINUE) > 0)) {
+ /* run the p+q asynchronously */
+ pr_debug("%s: (async) disks: %d len: %zu\n",
+ __func__, disks, len);
+ return do_async_gen_syndrome(chan, blocks, raid6_gfexp, offset,
+ disks, len, dma_src, submit);
+ }
+
+ /* 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) = scribble;
+ BUG_ON(len + offset > PAGE_SIZE);
+ }
+ if (!Q(blocks, disks)) {
+ Q(blocks, disks) = scribble;
+ BUG_ON(len + offset > PAGE_SIZE);
+ }
+ do_sync_gen_syndrome(blocks, offset, disks, len, submit);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(async_gen_syndrome);
+
+/**
+ * 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 = async_tx_find_channel(submit, DMA_PQ_VAL,
+ NULL, 0, blocks, disks,
+ len);
+ struct dma_device *device = chan ? chan->device : NULL;
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
+ dma_addr_t *dma_src = NULL;
+
+ BUG_ON(disks < 4);
+
+ if (submit->scribble)
+ dma_src = submit->scribble;
+ else if (sizeof(dma_addr_t) <= sizeof(struct page *))
+ dma_src = (dma_addr_t *) blocks;
+
+ if (dma_src && device && disks <= dma_maxpq(device, 0)) {
+ struct device *dev = device->dev;
+ dma_addr_t *pq = &dma_src[disks-2];
+ int i;
+
+ pr_debug("%s: (async) disks: %d len: %zu\n",
+ __func__, disks, len);
+ if (!P(blocks, disks))
+ dma_flags |= DMA_PREP_PQ_DISABLE_P;
+ if (!Q(blocks, disks))
+ dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+ for (i = 0; i < disks; i++)
+ if (likely(blocks[i])) {
+ BUG_ON(is_raid6_zero_block(blocks[i]));
+ dma_src[i] = dma_map_page(dev, blocks[i],
+ offset, len,
+ DMA_TO_DEVICE);
+ }
+
+ for (;;) {
+ tx = device->device_prep_dma_pq_val(chan, pq, dma_src,
+ disks - 2,
+ raid6_gfexp,
+ len, pqres,
+ dma_flags);
+ if (likely(tx))
+ break;
+ async_tx_quiesce(&submit->depend_tx);
+ dma_async_issue_pending(chan);
+ }
+ 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)
+{
+ scribble = alloc_page(GFP_KERNEL);
+
+ if (scribble)
+ return 0;
+
+ pr_err("%s: failed to allocate required spare page\n", __func__);
+
+ return -ENOMEM;
+}
+
+static void __exit async_pq_exit(void)
+{
+ put_page(scribble);
+}
+
+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 0000000..0c14d48
--- /dev/null
+++ b/crypto/async_tx/async_raid6_recov.c
@@ -0,0 +1,448 @@
+/*
+ * 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/dma-mapping.h>
+#include <linux/raid/pq.h>
+#include <linux/async_tx.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;
+ const u8 *amul, *bmul;
+ u8 ax, bx;
+ u8 *a, *b, *c;
+
+ if (dma) {
+ dma_addr_t dma_dest[2];
+ dma_addr_t dma_src[2];
+ struct device *dev = dma->dev;
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
+
+ dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+ dma_src[0] = dma_map_page(dev, srcs[0], 0, len, DMA_TO_DEVICE);
+ dma_src[1] = dma_map_page(dev, srcs[1], 0, len, DMA_TO_DEVICE);
+ tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 2, coef,
+ len, dma_flags);
+ if (tx) {
+ async_tx_submit(chan, tx, submit);
+ return tx;
+ }
+ }
+
+ /* 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;
+ const u8 *qmul; /* Q multiplier table */
+ u8 *d, *s;
+
+ if (dma) {
+ dma_addr_t dma_dest[2];
+ dma_addr_t dma_src[1];
+ struct device *dev = dma->dev;
+ struct dma_async_tx_descriptor *tx;
+ enum dma_ctrl_flags dma_flags = DMA_PREP_PQ_DISABLE_P;
+
+ dma_dest[1] = dma_map_page(dev, dest, 0, len, DMA_BIDIRECTIONAL);
+ dma_src[0] = dma_map_page(dev, src, 0, len, DMA_TO_DEVICE);
+ tx = dma->device_prep_dma_pq(chan, dma_dest, dma_src, 1, &coef,
+ len, dma_flags);
+ if (tx) {
+ async_tx_submit(chan, tx, submit);
+ return tx;
+ }
+ }
+
+ /* 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(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[4-2];
+ q = blocks[4-1];
+
+ 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, 0, 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(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 uninitialized_var(good);
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ if (i == faila || i == failb)
+ continue;
+ else {
+ good = i;
+ break;
+ }
+ }
+ BUG_ON(i >= 3);
+
+ p = blocks[5-2];
+ q = blocks[5-1];
+ 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, 0, tx, NULL, NULL, scribble);
+ tx = async_memcpy(dp, g, 0, 0, bytes, submit);
+ init_async_submit(submit, 0, 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_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_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, 0, 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] = (void *)raid6_empty_zero_page;
+ blocks[disks-2] = dp;
+ dq = blocks[failb];
+ blocks[failb] = (void *)raid6_empty_zero_page;
+ blocks[disks-1] = dq;
+
+ init_async_submit(submit, 0, 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_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_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, 0, 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)
+{
+ BUG_ON(faila == failb);
+ if (failb < faila)
+ swap(faila, failb);
+
+ pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
+
+ /* we need to preserve the contents of 'blocks' for the async
+ * case, so punt to synchronous if a scribble buffer is not available
+ */
+ if (!submit->scribble) {
+ void **ptrs = (void **) blocks;
+ int i;
+
+ async_tx_quiesce(&submit->depend_tx);
+ for (i = 0; i < disks; i++)
+ ptrs[i] = page_address(blocks[i]);
+
+ raid6_2data_recov(disks, bytes, faila, failb, ptrs);
+
+ async_tx_sync_epilog(submit);
+
+ return NULL;
+ }
+
+ switch (disks) {
+ case 4:
+ /* dma devices do not uniformly understand a zero source pq
+ * operation (in contrast to the synchronous case), so
+ * explicitly handle the 4 disk special case
+ */
+ return __2data_recov_4(bytes, faila, failb, blocks, submit);
+ case 5:
+ /* dma devices do not uniformly understand a single
+ * source pq operation (in contrast to the synchronous
+ * case), so explicitly handle the 5 disk special case
+ */
+ return __2data_recov_5(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;
+ struct page *srcs[2];
+
+ pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
+
+ /* we need to preserve the contents of 'blocks' for the async
+ * case, so punt to synchronous if a scribble buffer is not available
+ */
+ if (!scribble) {
+ void **ptrs = (void **) blocks;
+ int i;
+
+ async_tx_quiesce(&submit->depend_tx);
+ for (i = 0; i < disks; i++)
+ ptrs[i] = page_address(blocks[i]);
+
+ raid6_datap_recov(disks, bytes, faila, ptrs);
+
+ async_tx_sync_epilog(submit);
+
+ return NULL;
+ }
+
+ 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] = (void *)raid6_empty_zero_page;
+ blocks[disks-1] = dq;
+
+ /* in the 4 disk case we only need to perform a single source
+ * multiplication
+ */
+ if (disks == 4) {
+ int good = faila == 0 ? 1 : 0;
+ struct page *g = blocks[good];
+
+ init_async_submit(submit, 0, tx, NULL, NULL, scribble);
+ tx = async_memcpy(p, g, 0, 0, bytes, submit);
+
+ init_async_submit(submit, 0, tx, NULL, NULL, scribble);
+ tx = async_mult(dq, g, raid6_gfexp[good], bytes, submit);
+ } else {
+ init_async_submit(submit, 0, 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_XOR_DROP_DST, tx, NULL, NULL,
+ scribble);
+ tx = async_xor(dq, srcs, 0, 2, bytes, submit);
+
+ init_async_submit(submit, 0, 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
index 06eb6cc..60615fe 100644
--- a/crypto/async_tx/async_tx.c
+++ b/crypto/async_tx/async_tx.c
@@ -42,16 +42,21 @@ 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
- * @depend_tx: transaction dependency
+ * @submit: transaction dependency and submission modifiers
* @tx_type: transaction type
*/
struct dma_chan *
-__async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
- enum dma_transaction_type tx_type)
+__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))
@@ -59,17 +64,6 @@ __async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
return async_dma_find_channel(tx_type);
}
EXPORT_SYMBOL_GPL(__async_tx_find_channel);
-#else
-static int __init async_tx_init(void)
-{
- printk(KERN_INFO "async_tx: api initialized (sync-only)\n");
- return 0;
-}
-
-static void __exit async_tx_exit(void)
-{
- do { } while (0);
-}
#endif
@@ -83,8 +77,8 @@ static void
async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
struct dma_async_tx_descriptor *tx)
{
- struct dma_chan *chan;
- struct dma_device *device;
+ 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 */
@@ -96,11 +90,11 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
}
spin_unlock_bh(&depend_tx->lock);
- if (!intr_tx)
+ /* attached dependency, flush the parent channel */
+ if (!intr_tx) {
+ device->device_issue_pending(chan);
return;
-
- chan = depend_tx->chan;
- device = chan->device;
+ }
/* see if we can schedule an interrupt
* otherwise poll for completion
@@ -134,6 +128,7 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_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_ERROR)
panic("%s: DMA_ERROR waiting for depend_tx\n",
@@ -144,13 +139,14 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
/**
- * submit_disposition - 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.
+ * 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,
@@ -160,11 +156,12 @@ enum submit_disposition {
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 cb_fn, void *cb_param)
+ struct async_submit_ctl *submit)
{
- tx->callback = cb_fn;
- tx->callback_param = cb_param;
+ 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;
@@ -220,30 +217,29 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
tx->tx_submit(tx);
}
- if (flags & ASYNC_TX_ACK)
+ if (submit->flags & ASYNC_TX_ACK)
async_tx_ack(tx);
- if (depend_tx && (flags & ASYNC_TX_DEP_ACK))
+ if (depend_tx)
async_tx_ack(depend_tx);
}
EXPORT_SYMBOL_GPL(async_tx_submit);
/**
- * async_trigger_callback - schedules the callback function to be run after
- * any dependent operations have been completed.
- * @flags: ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
- * @depend_tx: 'callback' requires the completion of this transaction
- * @cb_fn: function to call after depend_tx completes
- * @cb_param: parameter to pass to the callback routine
+ * 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(enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_param)
+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;
@@ -262,14 +258,14 @@ async_trigger_callback(enum async_tx_flags flags,
if (tx) {
pr_debug("%s: (async)\n", __func__);
- async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
+ async_tx_submit(chan, tx, submit);
} else {
pr_debug("%s: (sync)\n", __func__);
/* wait for any prerequisite operations */
- async_tx_quiesce(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
- async_tx_sync_epilog(cb_fn, cb_param);
+ async_tx_sync_epilog(submit);
}
return tx;
@@ -295,9 +291,6 @@ void async_tx_quiesce(struct dma_async_tx_descriptor **tx)
}
EXPORT_SYMBOL_GPL(async_tx_quiesce);
-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/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index 95fe2c8..56b5f98 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -33,19 +33,16 @@
/* 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 page *dest, struct page **src_list,
- unsigned int offset, int src_cnt, size_t len,
- enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_param)
+ unsigned int offset, int src_cnt, size_t len, dma_addr_t *dma_src,
+ struct async_submit_ctl *submit)
{
struct dma_device *dma = chan->device;
- dma_addr_t *dma_src = (dma_addr_t *) src_list;
struct dma_async_tx_descriptor *tx = NULL;
int src_off = 0;
int i;
- dma_async_tx_callback _cb_fn;
- void *_cb_param;
- enum async_tx_flags async_flags;
+ 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;
int xor_src_cnt;
dma_addr_t dma_dest;
@@ -63,23 +60,23 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
}
while (src_cnt) {
- async_flags = flags;
+ submit->flags = flags_orig;
dma_flags = 0;
- xor_src_cnt = min(src_cnt, dma->max_xor);
+ xor_src_cnt = min(src_cnt, (int)dma->max_xor);
/* if we are submitting additional xors, leave the chain open,
* clear the callback parameters, and leave the destination
* buffer mapped
*/
if (src_cnt > xor_src_cnt) {
- async_flags &= ~ASYNC_TX_ACK;
+ submit->flags &= ~ASYNC_TX_ACK;
dma_flags = DMA_COMPL_SKIP_DEST_UNMAP;
- _cb_fn = NULL;
- _cb_param = NULL;
+ submit->cb_fn = NULL;
+ submit->cb_param = NULL;
} else {
- _cb_fn = cb_fn;
- _cb_param = cb_param;
+ submit->cb_fn = cb_fn_orig;
+ submit->cb_param = cb_param_orig;
}
- if (_cb_fn)
+ if (submit->cb_fn)
dma_flags |= DMA_PREP_INTERRUPT;
/* Since we have clobbered the src_list we are committed
@@ -90,7 +87,7 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
xor_src_cnt, len, dma_flags);
if (unlikely(!tx))
- async_tx_quiesce(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
/* spin wait for the preceeding transactions to complete */
while (unlikely(!tx)) {
@@ -101,11 +98,8 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
dma_flags);
}
- async_tx_submit(chan, tx, async_flags, depend_tx, _cb_fn,
- _cb_param);
-
- depend_tx = tx;
- flags |= ASYNC_TX_DEP_ACK;
+ async_tx_submit(chan, tx, submit);
+ submit->depend_tx = tx;
if (src_cnt > xor_src_cnt) {
/* drop completed sources */
@@ -124,23 +118,27 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
static void
do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
- int src_cnt, size_t len, enum async_tx_flags flags,
- dma_async_tx_callback cb_fn, void *cb_param)
+ int src_cnt, size_t len, struct async_submit_ctl *submit)
{
int i;
int xor_src_cnt;
int src_off = 0;
void *dest_buf;
- void **srcs = (void **) src_list;
+ void **srcs;
+
+ if (submit->scribble)
+ srcs = submit->scribble;
+ else
+ srcs = (void **) src_list;
- /* reuse the 'src_list' array to convert to buffer pointers */
+ /* convert to buffer pointers */
for (i = 0; i < src_cnt; i++)
srcs[i] = page_address(src_list[i]) + offset;
/* set destination address */
dest_buf = page_address(dest) + offset;
- if (flags & ASYNC_TX_XOR_ZERO_DST)
+ if (submit->flags & ASYNC_TX_XOR_ZERO_DST)
memset(dest_buf, 0, len);
while (src_cnt > 0) {
@@ -153,61 +151,70 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
src_off += xor_src_cnt;
}
- async_tx_sync_epilog(cb_fn, cb_param);
+ async_tx_sync_epilog(submit);
}
/**
* async_xor - attempt to xor a set of blocks with a dma engine.
- * 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.
* @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_list: array of source pages
+ * @offset: common src/dst offset 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_ACK, ASYNC_TX_DEP_ACK
- * @depend_tx: xor depends on the result of this transaction.
- * @cb_fn: function to call when the xor completes
- * @cb_param: parameter to pass to the callback routine
+ * @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, enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_param)
+ int src_cnt, size_t len, struct async_submit_ctl *submit)
{
- struct dma_chan *chan = async_tx_find_channel(depend_tx, DMA_XOR,
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR,
&dest, 1, src_list,
src_cnt, len);
+ dma_addr_t *dma_src = NULL;
+
BUG_ON(src_cnt <= 1);
- if (chan) {
+ if (submit->scribble)
+ dma_src = submit->scribble;
+ else if (sizeof(dma_addr_t) <= sizeof(struct page *))
+ dma_src = (dma_addr_t *) src_list;
+
+ if (dma_src && chan) {
/* run the xor asynchronously */
pr_debug("%s (async): len: %zu\n", __func__, len);
return do_async_xor(chan, dest, src_list, offset, src_cnt, len,
- flags, depend_tx, cb_fn, cb_param);
+ dma_src, submit);
} else {
/* 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 (flags & ASYNC_TX_XOR_DROP_DST) {
+ if (submit->flags & ASYNC_TX_XOR_DROP_DST) {
src_cnt--;
src_list++;
}
/* wait for any prerequisite operations */
- async_tx_quiesce(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
- do_sync_xor(dest, src_list, offset, src_cnt, len,
- flags, cb_fn, cb_param);
+ do_sync_xor(dest, src_list, offset, src_cnt, len, submit);
return NULL;
}
@@ -222,104 +229,90 @@ static int page_is_zero(struct page *p, unsigned int offset, size_t len)
}
/**
- * async_xor_zero_sum - attempt a xor parity check with a dma engine.
+ * 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. The dest page must be listed as a source
- * at index zero. The contents of this array may be overwritten.
+ * @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
- * @flags: ASYNC_TX_ACK, ASYNC_TX_DEP_ACK
- * @depend_tx: xor depends on the result of this transaction.
- * @cb_fn: function to call when the xor completes
- * @cb_param: parameter to pass to the callback routine
+ * @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_zero_sum(struct page *dest, struct page **src_list,
- unsigned int offset, int src_cnt, size_t len,
- u32 *result, enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_param)
+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 = async_tx_find_channel(depend_tx, DMA_ZERO_SUM,
+ struct dma_chan *chan = async_tx_find_channel(submit, DMA_XOR_VAL,
&dest, 1, src_list,
src_cnt, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx = NULL;
+ dma_addr_t *dma_src = NULL;
BUG_ON(src_cnt <= 1);
- if (device && src_cnt <= device->max_xor) {
- dma_addr_t *dma_src = (dma_addr_t *) src_list;
- unsigned long dma_prep_flags = cb_fn ? DMA_PREP_INTERRUPT : 0;
+ if (submit->scribble)
+ dma_src = submit->scribble;
+ else if (sizeof(dma_addr_t) <= sizeof(struct page *))
+ dma_src = (dma_addr_t *) src_list;
+
+ if (dma_src && device && src_cnt <= device->max_xor) {
+ unsigned long dma_prep_flags;
int i;
pr_debug("%s: (async) len: %zu\n", __func__, len);
+ dma_prep_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
for (i = 0; i < src_cnt; i++)
dma_src[i] = dma_map_page(device->dev, src_list[i],
offset, len, DMA_TO_DEVICE);
- tx = device->device_prep_dma_zero_sum(chan, dma_src, src_cnt,
- len, result,
- dma_prep_flags);
+ tx = device->device_prep_dma_xor_val(chan, dma_src, src_cnt,
+ len, result,
+ dma_prep_flags);
if (unlikely(!tx)) {
- async_tx_quiesce(&depend_tx);
+ async_tx_quiesce(&submit->depend_tx);
while (!tx) {
dma_async_issue_pending(chan);
- tx = device->device_prep_dma_zero_sum(chan,
+ tx = device->device_prep_dma_xor_val(chan,
dma_src, src_cnt, len, result,
dma_prep_flags);
}
}
- async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
+ async_tx_submit(chan, tx, submit);
} else {
- unsigned long xor_flags = flags;
+ 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__);
- xor_flags |= ASYNC_TX_XOR_DROP_DST;
- xor_flags &= ~ASYNC_TX_ACK;
+ submit->flags |= ASYNC_TX_XOR_DROP_DST;
+ submit->flags &= ~ASYNC_TX_ACK;
- tx = async_xor(dest, src_list, offset, src_cnt, len, xor_flags,
- depend_tx, NULL, NULL);
+ tx = async_xor(dest, src_list, offset, src_cnt, len, submit);
async_tx_quiesce(&tx);
- *result = page_is_zero(dest, offset, len) ? 0 : 1;
+ *result = !page_is_zero(dest, offset, len) << SUM_CHECK_P;
- async_tx_sync_epilog(cb_fn, cb_param);
+ async_tx_sync_epilog(submit);
+ submit->flags = flags_orig;
}
return tx;
}
-EXPORT_SYMBOL_GPL(async_xor_zero_sum);
-
-static int __init async_xor_init(void)
-{
- #ifdef CONFIG_DMA_ENGINE
- /* To conserve stack space the input src_list (array of page pointers)
- * is reused to hold the array of dma addresses passed to the driver.
- * This conversion is only possible when dma_addr_t is less than the
- * the size of a pointer. HIGHMEM64G is known to violate this
- * assumption.
- */
- BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(struct page *));
- #endif
-
- return 0;
-}
-
-static void __exit async_xor_exit(void)
-{
- do { } while (0);
-}
-
-module_init(async_xor_init);
-module_exit(async_xor_exit);
+EXPORT_SYMBOL_GPL(async_xor_val);
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("asynchronous xor/xor-zero-sum api");
diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c
new file mode 100644
index 0000000..98c83ca
--- /dev/null
+++ b/crypto/async_tx/raid6test.c
@@ -0,0 +1,241 @@
+/*
+ * 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/random.h>
+
+#undef pr
+#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
+
+#define NDISKS 16 /* Including P and Q */
+
+static struct page *dataptrs[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, j;
+
+ for (i = 0; i < disks; i++) {
+ for (j = 0; j < PAGE_SIZE/sizeof(u32); j += sizeof(u32)) {
+ u32 *p = page_address(data[i]) + j;
+
+ *p = random32();
+ }
+
+ 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;
+ addr_conv_t addr_conv[disks];
+ 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)
+{
+ addr_conv_t addr_conv[disks];
+ 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);
+ 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");
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 3b3c01b..912a51b 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -4,7 +4,7 @@
menuconfig DMADEVICES
bool "DMA Engine support"
- depends on !HIGHMEM64G && HAS_DMA
+ depends on HAS_DMA
help
DMA engines can do asynchronous data transfers without
involving the host CPU. Currently, this framework can be
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 5a87384..9659847 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -644,8 +644,12 @@ int dma_async_device_register(struct dma_device *device)
!device->device_prep_dma_memcpy);
BUG_ON(dma_has_cap(DMA_XOR, device->cap_mask) &&
!device->device_prep_dma_xor);
- BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
- !device->device_prep_dma_zero_sum);
+ BUG_ON(dma_has_cap(DMA_XOR_VAL, device->cap_mask) &&
+ !device->device_prep_dma_xor_val);
+ BUG_ON(dma_has_cap(DMA_PQ, device->cap_mask) &&
+ !device->device_prep_dma_pq);
+ BUG_ON(dma_has_cap(DMA_PQ_VAL, device->cap_mask) &&
+ !device->device_prep_dma_pq_val);
BUG_ON(dma_has_cap(DMA_MEMSET, device->cap_mask) &&
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_INTERRUPT, device->cap_mask) &&
@@ -939,49 +943,24 @@ EXPORT_SYMBOL(dma_async_tx_descriptor_init);
/* dma_wait_for_async_tx - spin wait for a transaction to complete
* @tx: in-flight transaction to wait on
- *
- * This routine assumes that tx was obtained from a call to async_memcpy,
- * async_xor, async_memset, etc which ensures that tx is "in-flight" (prepped
- * and submitted). Walking the parent chain is only meant to cover for DMA
- * drivers that do not implement the DMA_INTERRUPT capability and may race with
- * the driver's descriptor cleanup routine.
*/
enum dma_status
dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
{
- enum dma_status status;
- struct dma_async_tx_descriptor *iter;
- struct dma_async_tx_descriptor *parent;
+ unsigned long dma_sync_wait_timeout = jiffies + msecs_to_jiffies(5000);
if (!tx)
return DMA_SUCCESS;
- WARN_ONCE(tx->parent, "%s: speculatively walking dependency chain for"
- " %s\n", __func__, dma_chan_name(tx->chan));
-
- /* poll through the dependency chain, return when tx is complete */
- do {
- iter = tx;
-
- /* find the root of the unsubmitted dependency chain */
- do {
- parent = iter->parent;
- if (!parent)
- break;
- else
- iter = parent;
- } while (parent);
-
- /* there is a small window for ->parent == NULL and
- * ->cookie == -EBUSY
- */
- while (iter->cookie == -EBUSY)
- cpu_relax();
-
- status = dma_sync_wait(iter->chan, iter->cookie);
- } while (status == DMA_IN_PROGRESS || (iter != tx));
-
- return status;
+ while (tx->cookie == -EBUSY) {
+ if (time_after_eq(jiffies, dma_sync_wait_timeout)) {
+ pr_err("%s timeout waiting for descriptor submission\n",
+ __func__);
+ return DMA_ERROR;
+ }
+ cpu_relax();
+ }
+ return dma_sync_wait(tx->chan, tx->cookie);
}
EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index fb7da51..58e49e4 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -43,6 +43,11 @@ module_param(xor_sources, uint, S_IRUGO);
MODULE_PARM_DESC(xor_sources,
"Number of xor source buffers (default: 3)");
+static unsigned int pq_sources = 3;
+module_param(pq_sources, uint, S_IRUGO);
+MODULE_PARM_DESC(pq_sources,
+ "Number of p+q source buffers (default: 3)");
+
/*
* Initialization patterns. All bytes in the source buffer has bit 7
* set, all bytes in the destination buffer has bit 7 cleared.
@@ -227,6 +232,7 @@ static int dmatest_func(void *data)
dma_cookie_t cookie;
enum dma_status status;
enum dma_ctrl_flags flags;
+ u8 pq_coefs[pq_sources];
int ret;
int src_cnt;
int dst_cnt;
@@ -243,6 +249,11 @@ static int dmatest_func(void *data)
else if (thread->type == DMA_XOR) {
src_cnt = xor_sources | 1; /* force odd to ensure dst = src */
dst_cnt = 1;
+ } else if (thread->type == DMA_PQ) {
+ src_cnt = pq_sources | 1; /* force odd to ensure dst = src */
+ dst_cnt = 2;
+ for (i = 0; i < pq_sources; i++)
+ pq_coefs[i] = 1;
} else
goto err_srcs;
@@ -310,6 +321,15 @@ static int dmatest_func(void *data)
dma_dsts[0] + dst_off,
dma_srcs, xor_sources,
len, flags);
+ else if (thread->type == DMA_PQ) {
+ dma_addr_t dma_pq[dst_cnt];
+
+ for (i = 0; i < dst_cnt; i++)
+ dma_pq[i] = dma_dsts[i] + dst_off;
+ tx = dev->device_prep_dma_pq(chan, dma_pq, dma_srcs,
+ pq_sources, pq_coefs,
+ len, flags);
+ }
if (!tx) {
for (i = 0; i < src_cnt; i++)
@@ -446,6 +466,8 @@ static int dmatest_add_threads(struct dmatest_chan *dtc, enum dma_transaction_ty
op = "copy";
else if (type == DMA_XOR)
op = "xor";
+ else if (type == DMA_PQ)
+ op = "pq";
else
return -EINVAL;
@@ -501,6 +523,10 @@ static int dmatest_add_channel(struct dma_chan *chan)
cnt = dmatest_add_threads(dtc, DMA_XOR);
thread_count += cnt > 0 ?: 0;
}
+ if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
+ cnt = dmatest_add_threads(dtc, DMA_PQ);
+ thread_count += cnt > 0 ?: 0;
+ }
pr_info("dmatest: Started %u threads using %s\n",
thread_count, dma_chan_name(chan));
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index 2f05226..4496bc6 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -660,9 +660,9 @@ iop_adma_prep_dma_xor(struct dma_chan *chan, dma_addr_t dma_dest,
}
static struct dma_async_tx_descriptor *
-iop_adma_prep_dma_zero_sum(struct dma_chan *chan, dma_addr_t *dma_src,
- unsigned int src_cnt, size_t len, u32 *result,
- unsigned long flags)
+iop_adma_prep_dma_xor_val(struct dma_chan *chan, dma_addr_t *dma_src,
+ unsigned int src_cnt, size_t len, u32 *result,
+ unsigned long flags)
{
struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
struct iop_adma_desc_slot *sw_desc, *grp_start;
@@ -906,7 +906,7 @@ out:
#define IOP_ADMA_NUM_SRC_TEST 4 /* must be <= 15 */
static int __devinit
-iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
+iop_adma_xor_val_self_test(struct iop_adma_device *device)
{
int i, src_idx;
struct page *dest;
@@ -1002,7 +1002,7 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
PAGE_SIZE, DMA_TO_DEVICE);
/* skip zero sum if the capability is not present */
- if (!dma_has_cap(DMA_ZERO_SUM, dma_chan->device->cap_mask))
+ if (!dma_has_cap(DMA_XOR_VAL, dma_chan->device->cap_mask))
goto free_resources;
/* zero sum the sources with the destintation page */
@@ -1016,10 +1016,10 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
dma_srcs[i] = dma_map_page(dma_chan->device->dev,
zero_sum_srcs[i], 0, PAGE_SIZE,
DMA_TO_DEVICE);
- tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
- IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
- &zero_sum_result,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ tx = iop_adma_prep_dma_xor_val(dma_chan, dma_srcs,
+ IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
+ &zero_sum_result,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
cookie = iop_adma_tx_submit(tx);
iop_adma_issue_pending(dma_chan);
@@ -1072,10 +1072,10 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
dma_srcs[i] = dma_map_page(dma_chan->device->dev,
zero_sum_srcs[i], 0, PAGE_SIZE,
DMA_TO_DEVICE);
- tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
- IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
- &zero_sum_result,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ tx = iop_adma_prep_dma_xor_val(dma_chan, dma_srcs,
+ IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
+ &zero_sum_result,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
cookie = iop_adma_tx_submit(tx);
iop_adma_issue_pending(dma_chan);
@@ -1192,9 +1192,9 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
dma_dev->max_xor = iop_adma_get_max_xor();
dma_dev->device_prep_dma_xor = iop_adma_prep_dma_xor;
}
- if (dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask))
- dma_dev->device_prep_dma_zero_sum =
- iop_adma_prep_dma_zero_sum;
+ if (dma_has_cap(DMA_XOR_VAL, dma_dev->cap_mask))
+ dma_dev->device_prep_dma_xor_val =
+ iop_adma_prep_dma_xor_val;
if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
dma_dev->device_prep_dma_interrupt =
iop_adma_prep_dma_interrupt;
@@ -1249,7 +1249,7 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
if (dma_has_cap(DMA_XOR, dma_dev->cap_mask) ||
dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
- ret = iop_adma_xor_zero_sum_self_test(adev);
+ ret = iop_adma_xor_val_self_test(adev);
dev_dbg(&pdev->dev, "xor self test returned %d\n", ret);
if (ret)
goto err_free_iop_chan;
@@ -1257,12 +1257,12 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
dev_printk(KERN_INFO, &pdev->dev, "Intel(R) IOP: "
"( %s%s%s%s%s%s%s%s%s%s)\n",
- dma_has_cap(DMA_PQ_XOR, dma_dev->cap_mask) ? "pq_xor " : "",
+ dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "pq " : "",
dma_has_cap(DMA_PQ_UPDATE, dma_dev->cap_mask) ? "pq_update " : "",
- dma_has_cap(DMA_PQ_ZERO_SUM, dma_dev->cap_mask) ? "pq_zero_sum " : "",
+ dma_has_cap(DMA_PQ_VAL, dma_dev->cap_mask) ? "pq_val " : "",
dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
dma_has_cap(DMA_DUAL_XOR, dma_dev->cap_mask) ? "dual_xor " : "",
- dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask) ? "xor_zero_sum " : "",
+ dma_has_cap(DMA_XOR_VAL, dma_dev->cap_mask) ? "xor_val " : "",
dma_has_cap(DMA_MEMSET, dma_dev->cap_mask) ? "fill " : "",
dma_has_cap(DMA_MEMCPY_CRC32C, dma_dev->cap_mask) ? "cpy+crc " : "",
dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 36e0675..09c0c6e 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -124,6 +124,8 @@ config MD_RAID456
select MD_RAID6_PQ
select ASYNC_MEMCPY
select ASYNC_XOR
+ select ASYNC_PQ
+ select ASYNC_RAID6_RECOV
---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
@@ -152,9 +154,33 @@ config MD_RAID456
If unsure, say Y.
+config MULTICORE_RAID456
+ bool "RAID-4/RAID-5/RAID-6 Multicore processing (EXPERIMENTAL)"
+ depends on MD_RAID456
+ depends on SMP
+ depends on EXPERIMENTAL
+ ---help---
+ Enable the raid456 module to dispatch per-stripe raid operations to a
+ thread pool.
+
+ If unsure, say N.
+
config MD_RAID6_PQ
tristate
+config ASYNC_RAID6_TEST
+ tristate "Self test for hardware accelerated raid6 recovery"
+ depends on MD_RAID6_PQ
+ select ASYNC_RAID6_RECOV
+ ---help---
+ This is a one-shot self test that permutes through the
+ recovery of all the possible two disk failure scenarios for a
+ N-disk array. Recovery is performed with the asynchronous
+ raid6 recovery routines, and will optionally use an offload
+ engine if one is available.
+
+ If unsure, say N.
+
config MD_MULTIPATH
tristate "Multipath I/O support"
depends on BLK_DEV_MD
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index bb37fb1..0a5cf21 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -47,7 +47,9 @@
#include <linux/kthread.h>
#include <linux/raid/pq.h>
#include <linux/async_tx.h>
+#include <linux/async.h>
#include <linux/seq_file.h>
+#include <linux/cpu.h>
#include "md.h"
#include "raid5.h"
#include "bitmap.h"
@@ -499,11 +501,14 @@ async_copy_data(int frombio, struct bio *bio, struct page *page,
struct page *bio_page;
int i;
int page_offset;
+ struct async_submit_ctl submit;
if (bio->bi_sector >= sector)
page_offset = (signed)(bio->bi_sector - sector) * 512;
else
page_offset = (signed)(sector - bio->bi_sector) * -512;
+
+ init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
bio_for_each_segment(bvl, bio, i) {
int len = bio_iovec_idx(bio, i)->bv_len;
int clen;
@@ -525,15 +530,14 @@ async_copy_data(int frombio, struct bio *bio, struct page *page,
bio_page = bio_iovec_idx(bio, i)->bv_page;
if (frombio)
tx = async_memcpy(page, bio_page, page_offset,
- b_offset, clen,
- ASYNC_TX_DEP_ACK,
- tx, NULL, NULL);
+ b_offset, clen, &submit);
else
tx = async_memcpy(bio_page, page, b_offset,
- page_offset, clen,
- ASYNC_TX_DEP_ACK,
- tx, NULL, NULL);
+ page_offset, clen, &submit);
}
+ /* chain the operations */
+ submit.depend_tx = tx;
+
if (clen < len) /* hit end of page */
break;
page_offset += len;
@@ -592,6 +596,7 @@ static void ops_run_biofill(struct stripe_head *sh)
{
struct dma_async_tx_descriptor *tx = NULL;
raid5_conf_t *conf = sh->raid_conf;
+ struct async_submit_ctl submit;
int i;
pr_debug("%s: stripe %llu\n", __func__,
@@ -615,22 +620,34 @@ static void ops_run_biofill(struct stripe_head *sh)
}
atomic_inc(&sh->count);
- async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx,
- ops_complete_biofill, sh);
+ init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_biofill, sh, NULL);
+ async_trigger_callback(&submit);
}
-static void ops_complete_compute5(void *stripe_head_ref)
+static void mark_target_uptodate(struct stripe_head *sh, int target)
{
- struct stripe_head *sh = stripe_head_ref;
- int target = sh->ops.target;
- struct r5dev *tgt = &sh->dev[target];
+ struct r5dev *tgt;
- pr_debug("%s: stripe %llu\n", __func__,
- (unsigned long long)sh->sector);
+ if (target < 0)
+ return;
+ tgt = &sh->dev[target];
set_bit(R5_UPTODATE, &tgt->flags);
BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
clear_bit(R5_Wantcompute, &tgt->flags);
+}
+
+static void ops_complete_compute(void *stripe_head_ref)
+{
+ struct stripe_head *sh = stripe_head_ref;
+
+ pr_debug("%s: stripe %llu\n", __func__,
+ (unsigned long long)sh->sector);
+
+ /* mark the computed target(s) as uptodate */
+ mark_target_uptodate(sh, sh->ops.target);
+ mark_target_uptodate(sh, sh->ops.target2);
+
clear_bit(STRIPE_COMPUTE_RUN, &sh->state);
if (sh->check_state == check_state_compute_run)
sh->check_state = check_state_compute_result;
@@ -638,16 +655,24 @@ static void ops_complete_compute5(void *stripe_head_ref)
release_stripe(sh);
}
-static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh)
+/* return a pointer to the address conversion region of the scribble buffer */
+static addr_conv_t *to_addr_conv(struct stripe_head *sh,
+ struct raid5_percpu *percpu)
+{
+ return percpu->scribble + sizeof(struct page *) * (sh->disks + 2);
+}
+
+static struct dma_async_tx_descriptor *
+ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu)
{
- /* kernel stack size limits the total number of disks */
int disks = sh->disks;
- struct page *xor_srcs[disks];
+ struct page **xor_srcs = percpu->scribble;
int target = sh->ops.target;
struct r5dev *tgt = &sh->dev[target];
struct page *xor_dest = tgt->page;
int count = 0;
struct dma_async_tx_descriptor *tx;
+ struct async_submit_ctl submit;
int i;
pr_debug("%s: stripe %llu block: %d\n",
@@ -660,17 +685,207 @@ static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh)
atomic_inc(&sh->count);
+ init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
+ ops_complete_compute, sh, to_addr_conv(sh, percpu));
if (unlikely(count == 1))
- tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE,
- 0, NULL, ops_complete_compute5, sh);
+ tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
else
- tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
- ASYNC_TX_XOR_ZERO_DST, NULL,
- ops_complete_compute5, sh);
+ tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
return tx;
}
+/* set_syndrome_sources - populate source buffers for gen_syndrome
+ * @srcs - (struct page *) array of size sh->disks
+ * @sh - stripe_head to parse
+ *
+ * Populates srcs in proper layout order for the stripe and returns the
+ * 'count' of sources to be used in a call to async_gen_syndrome. The P
+ * destination buffer is recorded in srcs[count] and the Q destination
+ * is recorded in srcs[count+1]].
+ */
+static int set_syndrome_sources(struct page **srcs, struct stripe_head *sh)
+{
+ int disks = sh->disks;
+ int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
+ int d0_idx = raid6_d0(sh);
+ int count;
+ int i;
+
+ for (i = 0; i < disks; i++)
+ srcs[i] = (void *)raid6_empty_zero_page;
+
+ count = 0;
+ i = d0_idx;
+ do {
+ int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
+
+ srcs[slot] = sh->dev[i].page;
+ i = raid6_next_disk(i, disks);
+ } while (i != d0_idx);
+ BUG_ON(count != syndrome_disks);
+
+ return count;
+}
+
+static struct dma_async_tx_descriptor *
+ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
+{
+ int disks = sh->disks;
+ struct page **blocks = percpu->scribble;
+ int target;
+ int qd_idx = sh->qd_idx;
+ struct dma_async_tx_descriptor *tx;
+ struct async_submit_ctl submit;
+ struct r5dev *tgt;
+ struct page *dest;
+ int i;
+ int count;
+
+ if (sh->ops.target < 0)
+ target = sh->ops.target2;
+ else if (sh->ops.target2 < 0)
+ target = sh->ops.target;
+ else
+ /* we should only have one valid target */
+ BUG();
+ BUG_ON(target < 0);
+ pr_debug("%s: stripe %llu block: %d\n",
+ __func__, (unsigned long long)sh->sector, target);
+
+ tgt = &sh->dev[target];
+ BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
+ dest = tgt->page;
+
+ atomic_inc(&sh->count);
+
+ if (target == qd_idx) {
+ count = set_syndrome_sources(blocks, sh);
+ blocks[count] = NULL; /* regenerating p is not necessary */
+ BUG_ON(blocks[count+1] != dest); /* q should already be set */
+ init_async_submit(&submit, 0, NULL, ops_complete_compute, sh,
+ to_addr_conv(sh, percpu));
+ tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
+ } else {
+ /* Compute any data- or p-drive using XOR */
+ count = 0;
+ for (i = disks; i-- ; ) {
+ if (i == target || i == qd_idx)
+ continue;
+ blocks[count++] = sh->dev[i].page;
+ }
+
+ init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
+ ops_complete_compute, sh,
+ to_addr_conv(sh, percpu));
+ tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit);
+ }
+
+ return tx;
+}
+
+static struct dma_async_tx_descriptor *
+ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
+{
+ int i, count, disks = sh->disks;
+ int syndrome_disks = sh->ddf_layout ? disks : disks-2;
+ int d0_idx = raid6_d0(sh);
+ int faila = -1, failb = -1;
+ int target = sh->ops.target;
+ int target2 = sh->ops.target2;
+ struct r5dev *tgt = &sh->dev[target];
+ struct r5dev *tgt2 = &sh->dev[target2];
+ struct dma_async_tx_descriptor *tx;
+ struct page **blocks = percpu->scribble;
+ struct async_submit_ctl submit;
+
+ pr_debug("%s: stripe %llu block1: %d block2: %d\n",
+ __func__, (unsigned long long)sh->sector, target, target2);
+ BUG_ON(target < 0 || target2 < 0);
+ BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
+ BUG_ON(!test_bit(R5_Wantcompute, &tgt2->flags));
+
+ /* we need to open-code set_syndrome_sources to handle to the
+ * slot number conversion for 'faila' and 'failb'
+ */
+ for (i = 0; i < disks ; i++)
+ blocks[i] = (void *)raid6_empty_zero_page;
+ count = 0;
+ i = d0_idx;
+ do {
+ int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
+
+ blocks[slot] = sh->dev[i].page;
+
+ if (i == target)
+ faila = slot;
+ if (i == target2)
+ failb = slot;
+ i = raid6_next_disk(i, disks);
+ } while (i != d0_idx);
+ BUG_ON(count != syndrome_disks);
+
+ BUG_ON(faila == failb);
+ if (failb < faila)
+ swap(faila, failb);
+ pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
+ __func__, (unsigned long long)sh->sector, faila, failb);
+
+ atomic_inc(&sh->count);
+
+ if (failb == syndrome_disks+1) {
+ /* Q disk is one of the missing disks */
+ if (faila == syndrome_disks) {
+ /* Missing P+Q, just recompute */
+ init_async_submit(&submit, 0, NULL, ops_complete_compute,
+ sh, to_addr_conv(sh, percpu));
+ return async_gen_syndrome(blocks, 0, count+2,
+ STRIPE_SIZE, &submit);
+ } else {
+ struct page *dest;
+ int data_target;
+ int qd_idx = sh->qd_idx;
+
+ /* Missing D+Q: recompute D from P, then recompute Q */
+ if (target == qd_idx)
+ data_target = target2;
+ else
+ data_target = target;
+
+ count = 0;
+ for (i = disks; i-- ; ) {
+ if (i == data_target || i == qd_idx)
+ continue;
+ blocks[count++] = sh->dev[i].page;
+ }
+ dest = sh->dev[data_target].page;
+ init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
+ NULL, NULL, to_addr_conv(sh, percpu));
+ tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE,
+ &submit);
+
+ count = set_syndrome_sources(blocks, sh);
+ init_async_submit(&submit, 0, tx, ops_complete_compute,
+ sh, to_addr_conv(sh, percpu));
+ return async_gen_syndrome(blocks, 0, count+2,
+ STRIPE_SIZE, &submit);
+ }
+ }
+
+ init_async_submit(&submit, 0, NULL, ops_complete_compute, sh,
+ to_addr_conv(sh, percpu));
+ if (failb == syndrome_disks) {
+ /* We're missing D+P. */
+ return async_raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE,
+ faila, blocks, &submit);
+ } else {
+ /* We're missing D+D. */
+ return async_raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE,
+ faila, failb, blocks, &submit);
+ }
+}
+
+
static void ops_complete_prexor(void *stripe_head_ref)
{
struct stripe_head *sh = stripe_head_ref;
@@ -680,12 +895,13 @@ static void ops_complete_prexor(void *stripe_head_ref)
}
static struct dma_async_tx_descriptor *
-ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
+ops_run_prexor(struct stripe_head *sh, struct raid5_percpu *percpu,
+ struct dma_async_tx_descriptor *tx)
{
- /* kernel stack size limits the total number of disks */
int disks = sh->disks;
- struct page *xor_srcs[disks];
+ struct page **xor_srcs = percpu->scribble;
int count = 0, pd_idx = sh->pd_idx, i;
+ struct async_submit_ctl submit;
/* existing parity data subtracted */
struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
@@ -700,9 +916,9 @@ ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
xor_srcs[count++] = dev->page;
}
- tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
- ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx,
- ops_complete_prexor, sh);
+ init_async_submit(&submit, ASYNC_TX_XOR_DROP_DST, tx,
+ ops_complete_prexor, sh, to_addr_conv(sh, percpu));
+ tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
return tx;
}
@@ -742,17 +958,21 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
return tx;
}
-static void ops_complete_postxor(void *stripe_head_ref)
+static void ops_complete_reconstruct(void *stripe_head_ref)
{
struct stripe_head *sh = stripe_head_ref;
- int disks = sh->disks, i, pd_idx = sh->pd_idx;
+ int disks = sh->disks;
+ int pd_idx = sh->pd_idx;
+ int qd_idx = sh->qd_idx;
+ int i;
pr_debug("%s: stripe %llu\n", __func__,
(unsigned long long)sh->sector);
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
- if (dev->written || i == pd_idx)
+
+ if (dev->written || i == pd_idx || i == qd_idx)
set_bit(R5_UPTODATE, &dev->flags);
}
@@ -770,12 +990,12 @@ static void ops_complete_postxor(void *stripe_head_ref)
}
static void
-ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
+ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu,
+ struct dma_async_tx_descriptor *tx)
{
- /* kernel stack size limits the total number of disks */
int disks = sh->disks;
- struct page *xor_srcs[disks];
-
+ struct page **xor_srcs = percpu->scribble;
+ struct async_submit_ctl submit;
int count = 0, pd_idx = sh->pd_idx, i;
struct page *xor_dest;
int prexor = 0;
@@ -809,18 +1029,36 @@ ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
* set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
* for the synchronous xor case
*/
- flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK |
+ flags = ASYNC_TX_ACK |
(prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST);
atomic_inc(&sh->count);
- if (unlikely(count == 1)) {
- flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST);
- tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE,
- flags, tx, ops_complete_postxor, sh);
- } else
- tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
- flags, tx, ops_complete_postxor, sh);
+ init_async_submit(&submit, flags, tx, ops_complete_reconstruct, sh,
+ to_addr_conv(sh, percpu));
+ if (unlikely(count == 1))
+ tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
+ else
+ tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
+}
+
+static void
+ops_run_reconstruct6(struct stripe_head *sh, struct raid5_percpu *percpu,
+ struct dma_async_tx_descriptor *tx)
+{
+ struct async_submit_ctl submit;
+ struct page **blocks = percpu->scribble;
+ int count;
+
+ pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector);
+
+ count = set_syndrome_sources(blocks, sh);
+
+ atomic_inc(&sh->count);
+
+ init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_reconstruct,
+ sh, to_addr_conv(sh, percpu));
+ async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
}
static void ops_complete_check(void *stripe_head_ref)
@@ -835,63 +1073,115 @@ static void ops_complete_check(void *stripe_head_ref)
release_stripe(sh);
}
-static void ops_run_check(struct stripe_head *sh)
+static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu)
{
- /* kernel stack size limits the total number of disks */
int disks = sh->disks;
- struct page *xor_srcs[disks];
+ int pd_idx = sh->pd_idx;
+ int qd_idx = sh->qd_idx;
+ struct page *xor_dest;
+ struct page **xor_srcs = percpu->scribble;
struct dma_async_tx_descriptor *tx;
-
- int count = 0, pd_idx = sh->pd_idx, i;
- struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
+ struct async_submit_ctl submit;
+ int count;
+ int i;
pr_debug("%s: stripe %llu\n", __func__,
(unsigned long long)sh->sector);
+ count = 0;
+ xor_dest = sh->dev[pd_idx].page;
+ xor_srcs[count++] = xor_dest;
for (i = disks; i--; ) {
- struct r5dev *dev = &sh->dev[i];
- if (i != pd_idx)
- xor_srcs[count++] = dev->page;
+ if (i == pd_idx || i == qd_idx)
+ continue;
+ xor_srcs[count++] = sh->dev[i].page;
}
- tx = async_xor_zero_sum(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
- &sh->ops.zero_sum_result, 0, NULL, NULL, NULL);
+ init_async_submit(&submit, 0, NULL, NULL, NULL,
+ to_addr_conv(sh, percpu));
+ tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
+ &sh->ops.zero_sum_result, &submit);
+
+ atomic_inc(&sh->count);
+ init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_check, sh, NULL);
+ tx = async_trigger_callback(&submit);
+}
+
+static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu, int checkp)
+{
+ struct page **srcs = percpu->scribble;
+ struct async_submit_ctl submit;
+ int count;
+
+ pr_debug("%s: stripe %llu checkp: %d\n", __func__,
+ (unsigned long long)sh->sector, checkp);
+
+ count = set_syndrome_sources(srcs, sh);
+ if (!checkp)
+ srcs[count] = NULL;
atomic_inc(&sh->count);
- tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx,
- ops_complete_check, sh);
+ init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check,
+ sh, to_addr_conv(sh, percpu));
+ async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE,
+ &sh->ops.zero_sum_result, percpu->spare_page, &submit);
}
-static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request)
+static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
{
int overlap_clear = 0, i, disks = sh->disks;
struct dma_async_tx_descriptor *tx = NULL;
+ raid5_conf_t *conf = sh->raid_conf;
+ int level = conf->level;
+ struct raid5_percpu *percpu;
+ unsigned long cpu;
+ cpu = get_cpu();
+ percpu = per_cpu_ptr(conf->percpu, cpu);
if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
ops_run_biofill(sh);
overlap_clear++;
}
if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) {
- tx = ops_run_compute5(sh);
- /* terminate the chain if postxor is not set to be run */
- if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request))
+ if (level < 6)
+ tx = ops_run_compute5(sh, percpu);
+ else {
+ if (sh->ops.target2 < 0 || sh->ops.target < 0)
+ tx = ops_run_compute6_1(sh, percpu);
+ else
+ tx = ops_run_compute6_2(sh, percpu);
+ }
+ /* terminate the chain if reconstruct is not set to be run */
+ if (tx && !test_bit(STRIPE_OP_RECONSTRUCT, &ops_request))
async_tx_ack(tx);
}
if (test_bit(STRIPE_OP_PREXOR, &ops_request))
- tx = ops_run_prexor(sh, tx);
+ tx = ops_run_prexor(sh, percpu, tx);
if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) {
tx = ops_run_biodrain(sh, tx);
overlap_clear++;
}
- if (test_bit(STRIPE_OP_POSTXOR, &ops_request))
- ops_run_postxor(sh, tx);
+ if (test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) {
+ if (level < 6)
+ ops_run_reconstruct5(sh, percpu, tx);
+ else
+ ops_run_reconstruct6(sh, percpu, tx);
+ }
- if (test_bit(STRIPE_OP_CHECK, &ops_request))
- ops_run_check(sh);
+ if (test_bit(STRIPE_OP_CHECK, &ops_request)) {
+ if (sh->check_state == check_state_run)
+ ops_run_check_p(sh, percpu);
+ else if (sh->check_state == check_state_run_q)
+ ops_run_check_pq(sh, percpu, 0);
+ else if (sh->check_state == check_state_run_pq)
+ ops_run_check_pq(sh, percpu, 1);
+ else
+ BUG();
+ }
if (overlap_clear)
for (i = disks; i--; ) {
@@ -899,6 +1189,7 @@ static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request)
if (test_and_clear_bit(R5_Overlap, &dev->flags))
wake_up(&sh->raid_conf->wait_for_overlap);
}
+ put_cpu();
}
static int grow_one_stripe(raid5_conf_t *conf)
@@ -948,6 +1239,28 @@ static int grow_stripes(raid5_conf_t *conf, int num)
return 0;
}
+/**
+ * scribble_len - return the required size of the scribble region
+ * @num - total number of disks in the array
+ *
+ * The size must be enough to contain:
+ * 1/ a struct page pointer for each device in the array +2
+ * 2/ room to convert each entry in (1) to its corresponding dma
+ * (dma_map_page()) or page (page_address()) address.
+ *
+ * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
+ * calculate over all devices (not just the data blocks), using zeros in place
+ * of the P and Q blocks.
+ */
+static size_t scribble_len(int num)
+{
+ size_t len;
+
+ len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2);
+
+ return len;
+}
+
static int resize_stripes(raid5_conf_t *conf, int newsize)
{
/* Make all the stripes able to hold 'newsize' devices.
@@ -976,6 +1289,7 @@ static int resize_stripes(raid5_conf_t *conf, int newsize)
struct stripe_head *osh, *nsh;
LIST_HEAD(newstripes);
struct disk_info *ndisks;
+ unsigned long cpu;
int err;
struct kmem_cache *sc;
int i;
@@ -1041,7 +1355,7 @@ static int resize_stripes(raid5_conf_t *conf, int newsize)
/* Step 3.
* At this point, we are holding all the stripes so the array
* is completely stalled, so now is a good time to resize
- * conf->disks.
+ * conf->disks and the scribble region
*/
ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO);
if (ndisks) {
@@ -1052,10 +1366,30 @@ static int resize_stripes(raid5_conf_t *conf, int newsize)
} else
err = -ENOMEM;
+ get_online_cpus();
+ conf->scribble_len = scribble_len(newsize);
+ for_each_present_cpu(cpu) {
+ struct raid5_percpu *percpu;
+ void *scribble;
+
+ percpu = per_cpu_ptr(conf->percpu, cpu);
+ scribble = kmalloc(conf->scribble_len, GFP_NOIO);
+
+ if (scribble) {
+ kfree(percpu->scribble);
+ percpu->scribble = scribble;
+ } else {
+ err = -ENOMEM;
+ break;
+ }
+ }
+ put_online_cpus();
+
/* Step 4, return new stripes to service */
while(!list_empty(&newstripes)) {
nsh = list_entry(newstripes.next, struct stripe_head, lru);
list_del_init(&nsh->lru);
+
for (i=conf->raid_disks; i < newsize; i++)
if (nsh->dev[i].page == NULL) {
struct page *p = alloc_page(GFP_NOIO);
@@ -1594,258 +1928,13 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous)
}
-
-/*
- * Copy data between a page in the stripe cache, and one or more bion
- * The page could align with the middle of the bio, or there could be
- * several bion, each with several bio_vecs, which cover part of the page
- * Multiple bion are linked together on bi_next. There may be extras
- * at the end of this list. We ignore them.
- */
-static void copy_data(int frombio, struct bio *bio,
- struct page *page,
- sector_t sector)
-{
- char *pa = page_address(page);
- struct bio_vec *bvl;
- int i;
- int page_offset;
-
- if (bio->bi_sector >= sector)
- page_offset = (signed)(bio->bi_sector - sector) * 512;
- else
- page_offset = (signed)(sector - bio->bi_sector) * -512;
- bio_for_each_segment(bvl, bio, i) {
- int len = bio_iovec_idx(bio,i)->bv_len;
- int clen;
- int b_offset = 0;
-
- if (page_offset < 0) {
- b_offset = -page_offset;
- page_offset += b_offset;
- len -= b_offset;
- }
-
- if (len > 0 && page_offset + len > STRIPE_SIZE)
- clen = STRIPE_SIZE - page_offset;
- else clen = len;
-
- if (clen > 0) {
- char *ba = __bio_kmap_atomic(bio, i, KM_USER0);
- if (frombio)
- memcpy(pa+page_offset, ba+b_offset, clen);
- else
- memcpy(ba+b_offset, pa+page_offset, clen);
- __bio_kunmap_atomic(ba, KM_USER0);
- }
- if (clen < len) /* hit end of page */
- break;
- page_offset += len;
- }
-}
-
-#define check_xor() do { \
- if (count == MAX_XOR_BLOCKS) { \
- xor_blocks(count, STRIPE_SIZE, dest, ptr);\
- count = 0; \
- } \
- } while(0)
-
-static void compute_parity6(struct stripe_head *sh, int method)
-{
- raid5_conf_t *conf = sh->raid_conf;
- int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count;
- int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
- struct bio *chosen;
- /**** FIX THIS: This could be very bad if disks is close to 256 ****/
- void *ptrs[syndrome_disks+2];
-
- pd_idx = sh->pd_idx;
- qd_idx = sh->qd_idx;
- d0_idx = raid6_d0(sh);
-
- pr_debug("compute_parity, stripe %llu, method %d\n",
- (unsigned long long)sh->sector, method);
-
- switch(method) {
- case READ_MODIFY_WRITE:
- BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */
- case RECONSTRUCT_WRITE:
- for (i= disks; i-- ;)
- if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) {
- chosen = sh->dev[i].towrite;
- sh->dev[i].towrite = NULL;
-
- if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
- wake_up(&conf->wait_for_overlap);
-
- BUG_ON(sh->dev[i].written);
- sh->dev[i].written = chosen;
- }
- break;
- case CHECK_PARITY:
- BUG(); /* Not implemented yet */
- }
-
- for (i = disks; i--;)
- if (sh->dev[i].written) {
- sector_t sector = sh->dev[i].sector;
- struct bio *wbi = sh->dev[i].written;
- while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) {
- copy_data(1, wbi, sh->dev[i].page, sector);
- wbi = r5_next_bio(wbi, sector);
- }
-
- set_bit(R5_LOCKED, &sh->dev[i].flags);
- set_bit(R5_UPTODATE, &sh->dev[i].flags);
- }
-
- /* Note that unlike RAID-5, the ordering of the disks matters greatly.*/
-
- for (i = 0; i < disks; i++)
- ptrs[i] = (void *)raid6_empty_zero_page;
-
- count = 0;
- i = d0_idx;
- do {
- int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
-
- ptrs[slot] = page_address(sh->dev[i].page);
- if (slot < syndrome_disks &&
- !test_bit(R5_UPTODATE, &sh->dev[i].flags)) {
- printk(KERN_ERR "block %d/%d not uptodate "
- "on parity calc\n", i, count);
- BUG();
- }
-
- i = raid6_next_disk(i, disks);
- } while (i != d0_idx);
- BUG_ON(count != syndrome_disks);
-
- raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs);
-
- switch(method) {
- case RECONSTRUCT_WRITE:
- set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
- set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
- set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
- set_bit(R5_LOCKED, &sh->dev[qd_idx].flags);
- break;
- case UPDATE_PARITY:
- set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
- set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags);
- break;
- }
-}
-
-
-/* Compute one missing block */
-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], *dest, *p;
- int qd_idx = sh->qd_idx;
-
- pr_debug("compute_block_1, stripe %llu, idx %d\n",
- (unsigned long long)sh->sector, dd_idx);
-
- if ( dd_idx == qd_idx ) {
- /* We're actually computing the Q drive */
- compute_parity6(sh, UPDATE_PARITY);
- } else {
- 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;
- p = page_address(sh->dev[i].page);
- if (test_bit(R5_UPTODATE, &sh->dev[i].flags))
- ptr[count++] = p;
- else
- printk("compute_block() %d, stripe %llu, %d"
- " not present\n", dd_idx,
- (unsigned long long)sh->sector, i);
-
- check_xor();
- }
- if (count)
- xor_blocks(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);
- }
-}
-
-/* Compute two missing blocks */
-static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2)
-{
- int i, count, disks = sh->disks;
- int syndrome_disks = sh->ddf_layout ? disks : disks-2;
- int d0_idx = raid6_d0(sh);
- int faila = -1, failb = -1;
- /**** FIX THIS: This could be very bad if disks is close to 256 ****/
- void *ptrs[syndrome_disks+2];
-
- for (i = 0; i < disks ; i++)
- ptrs[i] = (void *)raid6_empty_zero_page;
- count = 0;
- i = d0_idx;
- do {
- int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
-
- ptrs[slot] = page_address(sh->dev[i].page);
-
- if (i == dd_idx1)
- faila = slot;
- if (i == dd_idx2)
- failb = slot;
- i = raid6_next_disk(i, disks);
- } while (i != d0_idx);
- BUG_ON(count != syndrome_disks);
-
- BUG_ON(faila == failb);
- if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; }
-
- pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n",
- (unsigned long long)sh->sector, dd_idx1, dd_idx2,
- faila, failb);
-
- if (failb == syndrome_disks+1) {
- /* Q disk is one of the missing disks */
- if (faila == syndrome_disks) {
- /* Missing P+Q, just recompute */
- compute_parity6(sh, UPDATE_PARITY);
- return;
- } else {
- /* We're missing D+Q; recompute D from P */
- compute_block_1(sh, ((dd_idx1 == sh->qd_idx) ?
- dd_idx2 : dd_idx1),
- 0);
- compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */
- return;
- }
- }
-
- /* We're missing D+P or D+D; */
- if (failb == syndrome_disks) {
- /* We're missing D+P. */
- raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs);
- } else {
- /* We're missing D+D. */
- raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb,
- ptrs);
- }
-
- /* Both the above update both missing blocks */
- set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags);
- set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags);
-}
-
static void
-schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s,
+schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
int rcw, int expand)
{
int i, pd_idx = sh->pd_idx, disks = sh->disks;
+ raid5_conf_t *conf = sh->raid_conf;
+ int level = conf->level;
if (rcw) {
/* if we are not expanding this is a proper write request, and
@@ -1858,7 +1947,7 @@ schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s,
} else
sh->reconstruct_state = reconstruct_state_run;
- set_bit(STRIPE_OP_POSTXOR, &s->ops_request);
+ set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
@@ -1871,17 +1960,18 @@ schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s,
s->locked++;
}
}
- if (s->locked + 1 == disks)
+ if (s->locked + conf->max_degraded == disks)
if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state))
- atomic_inc(&sh->raid_conf->pending_full_writes);
+ atomic_inc(&conf->pending_full_writes);
} else {
+ BUG_ON(level == 6);
BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) ||
test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags)));
sh->reconstruct_state = reconstruct_state_prexor_drain_run;
set_bit(STRIPE_OP_PREXOR, &s->ops_request);
set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
- set_bit(STRIPE_OP_POSTXOR, &s->ops_request);
+ set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
@@ -1899,13 +1989,22 @@ schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s,
}
}
- /* keep the parity disk locked while asynchronous operations
+ /* keep the parity disk(s) locked while asynchronous operations
* are in flight
*/
set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
s->locked++;
+ if (level == 6) {
+ int qd_idx = sh->qd_idx;
+ struct r5dev *dev = &sh->dev[qd_idx];
+
+ set_bit(R5_LOCKED, &dev->flags);
+ clear_bit(R5_UPTODATE, &dev->flags);
+ s->locked++;
+ }
+
pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
__func__, (unsigned long long)sh->sector,
s->locked, s->ops_request);
@@ -1986,13 +2085,6 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, in
static void end_reshape(raid5_conf_t *conf);
-static int page_is_zero(struct page *p)
-{
- char *a = page_address(p);
- return ((*(u32*)a) == 0 &&
- memcmp(a, a+4, STRIPE_SIZE-4)==0);
-}
-
static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous,
struct stripe_head *sh)
{
@@ -2133,9 +2225,10 @@ static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s,
set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
set_bit(R5_Wantcompute, &dev->flags);
sh->ops.target = disk_idx;
+ sh->ops.target2 = -1;
s->req_compute = 1;
/* Careful: from this point on 'uptodate' is in the eye
- * of raid5_run_ops which services 'compute' operations
+ * of raid_run_ops which services 'compute' operations
* before writes. R5_Wantcompute flags a block that will
* be R5_UPTODATE by the time it is needed for a
* subsequent operation.
@@ -2174,61 +2267,104 @@ static void handle_stripe_fill5(struct stripe_head *sh,
set_bit(STRIPE_HANDLE, &sh->state);
}
-static void handle_stripe_fill6(struct stripe_head *sh,
- struct stripe_head_state *s, struct r6_state *r6s,
- int disks)
+/* fetch_block6 - checks the given member device to see if its data needs
+ * to be read or computed to satisfy a request.
+ *
+ * Returns 1 when no more member devices need to be checked, otherwise returns
+ * 0 to tell the loop in handle_stripe_fill6 to continue
+ */
+static int fetch_block6(struct stripe_head *sh, struct stripe_head_state *s,
+ struct r6_state *r6s, int disk_idx, int disks)
{
- int i;
- for (i = disks; i--; ) {
- struct r5dev *dev = &sh->dev[i];
- if (!test_bit(R5_LOCKED, &dev->flags) &&
- !test_bit(R5_UPTODATE, &dev->flags) &&
- (dev->toread || (dev->towrite &&
- !test_bit(R5_OVERWRITE, &dev->flags)) ||
- s->syncing || s->expanding ||
- (s->failed >= 1 &&
- (sh->dev[r6s->failed_num[0]].toread ||
- s->to_write)) ||
- (s->failed >= 2 &&
- (sh->dev[r6s->failed_num[1]].toread ||
- s->to_write)))) {
- /* we would like to get this block, possibly
- * by computing it, but we might not be able to
+ struct r5dev *dev = &sh->dev[disk_idx];
+ struct r5dev *fdev[2] = { &sh->dev[r6s->failed_num[0]],
+ &sh->dev[r6s->failed_num[1]] };
+
+ if (!test_bit(R5_LOCKED, &dev->flags) &&
+ !test_bit(R5_UPTODATE, &dev->flags) &&
+ (dev->toread ||
+ (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
+ s->syncing || s->expanding ||
+ (s->failed >= 1 &&
+ (fdev[0]->toread || s->to_write)) ||
+ (s->failed >= 2 &&
+ (fdev[1]->toread || s->to_write)))) {
+ /* we would like to get this block, possibly by computing it,
+ * otherwise read it if the backing disk is insync
+ */
+ BUG_ON(test_bit(R5_Wantcompute, &dev->flags));
+ BUG_ON(test_bit(R5_Wantread, &dev->flags));
+ if ((s->uptodate == disks - 1) &&
+ (s->failed && (disk_idx == r6s->failed_num[0] ||
+ disk_idx == r6s->failed_num[1]))) {
+ /* have disk failed, and we're requested to fetch it;
+ * do compute it
*/
- if ((s->uptodate == disks - 1) &&
- (s->failed && (i == r6s->failed_num[0] ||
- i == r6s->failed_num[1]))) {
- pr_debug("Computing stripe %llu block %d\n",
- (unsigned long long)sh->sector, i);
- compute_block_1(sh, i, 0);
- s->uptodate++;
- } else if ( s->uptodate == disks-2 && s->failed >= 2 ) {
- /* Computing 2-failure is *very* expensive; only
- * do it if failed >= 2
- */
- int other;
- for (other = disks; other--; ) {
- if (other == i)
- continue;
- if (!test_bit(R5_UPTODATE,
- &sh->dev[other].flags))
- break;
- }
- BUG_ON(other < 0);
- pr_debug("Computing stripe %llu blocks %d,%d\n",
- (unsigned long long)sh->sector,
- i, other);
- compute_block_2(sh, i, other);
- s->uptodate += 2;
- } else if (test_bit(R5_Insync, &dev->flags)) {
- set_bit(R5_LOCKED, &dev->flags);
- set_bit(R5_Wantread, &dev->flags);
- s->locked++;
- pr_debug("Reading block %d (sync=%d)\n",
- i, s->syncing);
+ pr_debug("Computing stripe %llu block %d\n",
+ (unsigned long long)sh->sector, disk_idx);
+ set_bit(STRIPE_COMPUTE_RUN, &sh->state);
+ set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
+ set_bit(R5_Wantcompute, &dev->flags);
+ sh->ops.target = disk_idx;
+ sh->ops.target2 = -1; /* no 2nd target */
+ s->req_compute = 1;
+ s->uptodate++;
+ return 1;
+ } else if (s->uptodate == disks-2 && s->failed >= 2) {
+ /* Computing 2-failure is *very* expensive; only
+ * do it if failed >= 2
+ */
+ int other;
+ for (other = disks; other--; ) {
+ if (other == disk_idx)
+ continue;
+ if (!test_bit(R5_UPTODATE,
+ &sh->dev[other].flags))
+ break;
}
+ BUG_ON(other < 0);
+ pr_debug("Computing stripe %llu blocks %d,%d\n",
+ (unsigned long long)sh->sector,
+ disk_idx, other);
+ set_bit(STRIPE_COMPUTE_RUN, &sh->state);
+ set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
+ set_bit(R5_Wantcompute, &sh->dev[disk_idx].flags);
+ set_bit(R5_Wantcompute, &sh->dev[other].flags);
+ sh->ops.target = disk_idx;
+ sh->ops.target2 = other;
+ s->uptodate += 2;
+ s->req_compute = 1;
+ return 1;
+ } else if (test_bit(R5_Insync, &dev->flags)) {
+ set_bit(R5_LOCKED, &dev->flags);
+ set_bit(R5_Wantread, &dev->flags);
+ s->locked++;
+ pr_debug("Reading block %d (sync=%d)\n",
+ disk_idx, s->syncing);
}
}
+
+ return 0;
+}
+
+/**
+ * handle_stripe_fill6 - read or compute data to satisfy pending requests.
+ */
+static void handle_stripe_fill6(struct stripe_head *sh,
+ struct stripe_head_state *s, struct r6_state *r6s,
+ int disks)
+{
+ int i;
+
+ /* look for blocks to read/compute, skip this if a compute
+ * is already in flight, or if the stripe contents are in the
+ * midst of changing due to a write
+ */
+ if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
+ !sh->reconstruct_state)
+ for (i = disks; i--; )
+ if (fetch_block6(sh, s, r6s, i, disks))
+ break;
set_bit(STRIPE_HANDLE, &sh->state);
}
@@ -2362,114 +2498,61 @@ static void handle_stripe_dirtying5(raid5_conf_t *conf,
*/
/* since handle_stripe can be called at any time we need to handle the
* case where a compute block operation has been submitted and then a
- * subsequent call wants to start a write request. raid5_run_ops only
- * handles the case where compute block and postxor are requested
+ * subsequent call wants to start a write request. raid_run_ops only
+ * handles the case where compute block and reconstruct are requested
* simultaneously. If this is not the case then new writes need to be
* held off until the compute completes.
*/
if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
(s->locked == 0 && (rcw == 0 || rmw == 0) &&
!test_bit(STRIPE_BIT_DELAY, &sh->state)))
- schedule_reconstruction5(sh, s, rcw == 0, 0);
+ schedule_reconstruction(sh, s, rcw == 0, 0);
}
static void handle_stripe_dirtying6(raid5_conf_t *conf,
struct stripe_head *sh, struct stripe_head_state *s,
struct r6_state *r6s, int disks)
{
- int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i;
+ int rcw = 0, pd_idx = sh->pd_idx, i;
int qd_idx = sh->qd_idx;
+
+ set_bit(STRIPE_HANDLE, &sh->state);
for (i = disks; i--; ) {
struct r5dev *dev = &sh->dev[i];
- /* Would I have to read this buffer for reconstruct_write */
- if (!test_bit(R5_OVERWRITE, &dev->flags)
- && i != pd_idx && i != qd_idx
- && (!test_bit(R5_LOCKED, &dev->flags)
- ) &&
- !test_bit(R5_UPTODATE, &dev->flags)) {
- if (test_bit(R5_Insync, &dev->flags)) rcw++;
- else {
- pr_debug("raid6: must_compute: "
- "disk %d flags=%#lx\n", i, dev->flags);
- must_compute++;
+ /* check if we haven't enough data */
+ if (!test_bit(R5_OVERWRITE, &dev->flags) &&
+ i != pd_idx && i != qd_idx &&
+ !test_bit(R5_LOCKED, &dev->flags) &&
+ !(test_bit(R5_UPTODATE, &dev->flags) ||
+ test_bit(R5_Wantcompute, &dev->flags))) {
+ rcw++;
+ if (!test_bit(R5_Insync, &dev->flags))
+ continue; /* it's a failed drive */
+
+ if (
+ test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
+ pr_debug("Read_old stripe %llu "
+ "block %d for Reconstruct\n",
+ (unsigned long long)sh->sector, i);
+ set_bit(R5_LOCKED, &dev->flags);
+ set_bit(R5_Wantread, &dev->flags);
+ s->locked++;
+ } else {
+ pr_debug("Request delayed stripe %llu "
+ "block %d for Reconstruct\n",
+ (unsigned long long)sh->sector, i);
+ set_bit(STRIPE_DELAYED, &sh->state);
+ set_bit(STRIPE_HANDLE, &sh->state);
}
}
}
- pr_debug("for sector %llu, rcw=%d, must_compute=%d\n",
- (unsigned long long)sh->sector, rcw, must_compute);
- set_bit(STRIPE_HANDLE, &sh->state);
-
- if (rcw > 0)
- /* want reconstruct write, but need to get some data */
- for (i = disks; i--; ) {
- struct r5dev *dev = &sh->dev[i];
- if (!test_bit(R5_OVERWRITE, &dev->flags)
- && !(s->failed == 0 && (i == pd_idx || i == qd_idx))
- && !test_bit(R5_LOCKED, &dev->flags) &&
- !test_bit(R5_UPTODATE, &dev->flags) &&
- test_bit(R5_Insync, &dev->flags)) {
- if (
- test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
- pr_debug("Read_old stripe %llu "
- "block %d for Reconstruct\n",
- (unsigned long long)sh->sector, i);
- set_bit(R5_LOCKED, &dev->flags);
- set_bit(R5_Wantread, &dev->flags);
- s->locked++;
- } else {
- pr_debug("Request delayed stripe %llu "
- "block %d for Reconstruct\n",
- (unsigned long long)sh->sector, i);
- set_bit(STRIPE_DELAYED, &sh->state);
- set_bit(STRIPE_HANDLE, &sh->state);
- }
- }
- }
/* now if nothing is locked, and if we have enough data, we can start a
* write request
*/
- if (s->locked == 0 && rcw == 0 &&
+ if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
+ s->locked == 0 && rcw == 0 &&
!test_bit(STRIPE_BIT_DELAY, &sh->state)) {
- if (must_compute > 0) {
- /* We have failed blocks and need to compute them */
- switch (s->failed) {
- case 0:
- BUG();
- case 1:
- compute_block_1(sh, r6s->failed_num[0], 0);
- break;
- case 2:
- compute_block_2(sh, r6s->failed_num[0],
- r6s->failed_num[1]);
- break;
- default: /* This request should have been failed? */
- BUG();
- }
- }
-
- pr_debug("Computing parity for stripe %llu\n",
- (unsigned long long)sh->sector);
- compute_parity6(sh, RECONSTRUCT_WRITE);
- /* now every locked buffer is ready to be written */
- for (i = disks; i--; )
- if (test_bit(R5_LOCKED, &sh->dev[i].flags)) {
- pr_debug("Writing stripe %llu block %d\n",
- (unsigned long long)sh->sector, i);
- s->locked++;
- set_bit(R5_Wantwrite, &sh->dev[i].flags);
- }
- if (s->locked == disks)
- if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state))
- atomic_inc(&conf->pending_full_writes);
- /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */
- set_bit(STRIPE_INSYNC, &sh->state);
-
- if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
- atomic_dec(&conf->preread_active_stripes);
- if (atomic_read(&conf->preread_active_stripes) <
- IO_THRESHOLD)
- md_wakeup_thread(conf->mddev->thread);
- }
+ schedule_reconstruction(sh, s, 1, 0);
}
}
@@ -2528,7 +2611,7 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh,
* we are done. Otherwise update the mismatch count and repair
* parity if !MD_RECOVERY_CHECK
*/
- if (sh->ops.zero_sum_result == 0)
+ if ((sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) == 0)
/* parity is correct (on disc,
* not in buffer any more)
*/
@@ -2545,6 +2628,7 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh,
set_bit(R5_Wantcompute,
&sh->dev[sh->pd_idx].flags);
sh->ops.target = sh->pd_idx;
+ sh->ops.target2 = -1;
s->uptodate++;
}
}
@@ -2561,67 +2645,74 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh,
static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh,
- struct stripe_head_state *s,
- struct r6_state *r6s, struct page *tmp_page,
- int disks)
+ struct stripe_head_state *s,
+ struct r6_state *r6s, int disks)
{
- int update_p = 0, update_q = 0;
- struct r5dev *dev;
int pd_idx = sh->pd_idx;
int qd_idx = sh->qd_idx;
+ struct r5dev *dev;
set_bit(STRIPE_HANDLE, &sh->state);
BUG_ON(s->failed > 2);
- BUG_ON(s->uptodate < disks);
+
/* Want to check and possibly repair P and Q.
* However there could be one 'failed' device, in which
* case we can only check one of them, possibly using the
* other to generate missing data
*/
- /* If !tmp_page, we cannot do the calculations,
- * but as we have set STRIPE_HANDLE, we will soon be called
- * by stripe_handle with a tmp_page - just wait until then.
- */
- if (tmp_page) {
+ switch (sh->check_state) {
+ case check_state_idle:
+ /* start a new check operation if there are < 2 failures */
if (s->failed == r6s->q_failed) {
- /* The only possible failed device holds 'Q', so it
+ /* The only possible failed device holds Q, so it
* makes sense to check P (If anything else were failed,
* we would have used P to recreate it).
*/
- compute_block_1(sh, pd_idx, 1);
- if (!page_is_zero(sh->dev[pd_idx].page)) {
- compute_block_1(sh, pd_idx, 0);
- update_p = 1;
- }
+ sh->check_state = check_state_run;
}
if (!r6s->q_failed && s->failed < 2) {
- /* q is not failed, and we didn't use it to generate
+ /* Q is not failed, and we didn't use it to generate
* anything, so it makes sense to check it
*/
- memcpy(page_address(tmp_page),
- page_address(sh->dev[qd_idx].page),
- STRIPE_SIZE);
- compute_parity6(sh, UPDATE_PARITY);
- if (memcmp(page_address(tmp_page),
- page_address(sh->dev[qd_idx].page),
- STRIPE_SIZE) != 0) {
- clear_bit(STRIPE_INSYNC, &sh->state);
- update_q = 1;
- }
+ if (sh->check_state == check_state_run)
+ sh->check_state = check_state_run_pq;
+ else
+ sh->check_state = check_state_run_q;
}
- if (update_p || update_q) {
- conf->mddev->resync_mismatches += STRIPE_SECTORS;
- if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))
- /* don't try to repair!! */
- update_p = update_q = 0;
+
+ /* discard potentially stale zero_sum_result */
+ sh->ops.zero_sum_result = 0;
+
+ if (sh->check_state == check_state_run) {
+ /* async_xor_zero_sum destroys the contents of P */
+ clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
+ s->uptodate--;
}
+ if (sh->check_state >= check_state_run &&
+ sh->check_state <= check_state_run_pq) {
+ /* async_syndrome_zero_sum preserves P and Q, so
+ * no need to mark them !uptodate here
+ */
+ set_bit(STRIPE_OP_CHECK, &s->ops_request);
+ break;
+ }
+
+ /* we have 2-disk failure */
+ BUG_ON(s->failed != 2);
+ /* fall through */
+ case check_state_compute_result:
+ sh->check_state = check_state_idle;
+
+ /* check that a write has not made the stripe insync */
+ if (test_bit(STRIPE_INSYNC, &sh->state))
+ break;
/* now write out any block on a failed drive,
- * or P or Q if they need it
+ * or P or Q if they were recomputed
*/
-
+ BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */
if (s->failed == 2) {
dev = &sh->dev[r6s->failed_num[1]];
s->locked++;
@@ -2634,14 +2725,13 @@ static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh,
set_bit(R5_LOCKED, &dev->flags);
set_bit(R5_Wantwrite, &dev->flags);
}
-
- if (update_p) {
+ if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
dev = &sh->dev[pd_idx];
s->locked++;
set_bit(R5_LOCKED, &dev->flags);
set_bit(R5_Wantwrite, &dev->flags);
}
- if (update_q) {
+ if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
dev = &sh->dev[qd_idx];
s->locked++;
set_bit(R5_LOCKED, &dev->flags);
@@ -2650,6 +2740,70 @@ static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh,
clear_bit(STRIPE_DEGRADED, &sh->state);
set_bit(STRIPE_INSYNC, &sh->state);
+ break;
+ case check_state_run:
+ case check_state_run_q:
+ case check_state_run_pq:
+ break; /* we will be called again upon completion */
+ case check_state_check_result:
+ sh->check_state = check_state_idle;
+
+ /* handle a successful check operation, if parity is correct
+ * we are done. Otherwise update the mismatch count and repair
+ * parity if !MD_RECOVERY_CHECK
+ */
+ if (sh->ops.zero_sum_result == 0) {
+ /* both parities are correct */
+ if (!s->failed)
+ set_bit(STRIPE_INSYNC, &sh->state);
+ else {
+ /* in contrast to the raid5 case we can validate
+ * parity, but still have a failure to write
+ * back
+ */
+ sh->check_state = check_state_compute_result;
+ /* Returning at this point means that we may go
+ * off and bring p and/or q uptodate again so
+ * we make sure to check zero_sum_result again
+ * to verify if p or q need writeback
+ */
+ }
+ } else {
+ conf->mddev->resync_mismatches += STRIPE_SECTORS;
+ if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery))
+ /* don't try to repair!! */
+ set_bit(STRIPE_INSYNC, &sh->state);
+ else {
+ int *target = &sh->ops.target;
+
+ sh->ops.target = -1;
+ sh->ops.target2 = -1;
+ sh->check_state = check_state_compute_run;
+ set_bit(STRIPE_COMPUTE_RUN, &sh->state);
+ set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
+ if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
+ set_bit(R5_Wantcompute,
+ &sh->dev[pd_idx].flags);
+ *target = pd_idx;
+ target = &sh->ops.target2;
+ s->uptodate++;
+ }
+ if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
+ set_bit(R5_Wantcompute,
+ &sh->dev[qd_idx].flags);
+ *target = qd_idx;
+ s->uptodate++;
+ }
+ }
+ }
+ break;
+ case check_state_compute_run:
+ break;
+ default:
+ printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n",
+ __func__, sh->check_state,
+ (unsigned long long) sh->sector);
+ BUG();
}
}
@@ -2667,6 +2821,7 @@ static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh,
if (i != sh->pd_idx && i != sh->qd_idx) {
int dd_idx, j;
struct stripe_head *sh2;
+ struct async_submit_ctl submit;
sector_t bn = compute_blocknr(sh, i, 1);
sector_t s = raid5_compute_sector(conf, bn, 0,
@@ -2686,9 +2841,10 @@ static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh,
}
/* place all the copies on one channel */
+ init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
tx = async_memcpy(sh2->dev[dd_idx].page,
- sh->dev[i].page, 0, 0, STRIPE_SIZE,
- ASYNC_TX_DEP_ACK, tx, NULL, NULL);
+ sh->dev[i].page, 0, 0, STRIPE_SIZE,
+ &submit);
set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags);
@@ -2974,7 +3130,7 @@ static bool handle_stripe5(struct stripe_head *sh)
/* Need to write out all blocks after computing parity */
sh->disks = conf->raid_disks;
stripe_set_idx(sh->sector, conf, 0, sh);
- schedule_reconstruction5(sh, &s, 1, 1);
+ schedule_reconstruction(sh, &s, 1, 1);
} else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
clear_bit(STRIPE_EXPAND_READY, &sh->state);
atomic_dec(&conf->reshape_stripes);
@@ -2994,7 +3150,7 @@ static bool handle_stripe5(struct stripe_head *sh)
md_wait_for_blocked_rdev(blocked_rdev, conf->mddev);
if (s.ops_request)
- raid5_run_ops(sh, s.ops_request);
+ raid_run_ops(sh, s.ops_request);
ops_run_io(sh, &s);
@@ -3003,7 +3159,7 @@ static bool handle_stripe5(struct stripe_head *sh)
return blocked_rdev == NULL;
}
-static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
+static bool handle_stripe6(struct stripe_head *sh)
{
raid5_conf_t *conf = sh->raid_conf;
int disks = sh->disks;
@@ -3015,9 +3171,10 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
mdk_rdev_t *blocked_rdev = NULL;
pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
- "pd_idx=%d, qd_idx=%d\n",
+ "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
(unsigned long long)sh->sector, sh->state,
- atomic_read(&sh->count), pd_idx, qd_idx);
+ atomic_read(&sh->count), pd_idx, qd_idx,
+ sh->check_state, sh->reconstruct_state);
memset(&s, 0, sizeof(s));
spin_lock(&sh->lock);
@@ -3037,35 +3194,24 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
i, dev->flags, dev->toread, dev->towrite, dev->written);
- /* maybe we can reply to a read */
- if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) {
- struct bio *rbi, *rbi2;
- pr_debug("Return read for disc %d\n", i);
- spin_lock_irq(&conf->device_lock);
- rbi = dev->toread;
- dev->toread = NULL;
- if (test_and_clear_bit(R5_Overlap, &dev->flags))
- wake_up(&conf->wait_for_overlap);
- spin_unlock_irq(&conf->device_lock);
- while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) {
- copy_data(0, rbi, dev->page, dev->sector);
- rbi2 = r5_next_bio(rbi, dev->sector);
- spin_lock_irq(&conf->device_lock);
- if (!raid5_dec_bi_phys_segments(rbi)) {
- rbi->bi_next = return_bi;
- return_bi = rbi;
- }
- spin_unlock_irq(&conf->device_lock);
- rbi = rbi2;
- }
- }
+ /* maybe we can reply to a read
+ *
+ * new wantfill requests are only permitted while
+ * ops_complete_biofill is guaranteed to be inactive
+ */
+ if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread &&
+ !test_bit(STRIPE_BIOFILL_RUN, &sh->state))
+ set_bit(R5_Wantfill, &dev->flags);
/* now count some things */
if (test_bit(R5_LOCKED, &dev->flags)) s.locked++;
if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++;
+ if (test_bit(R5_Wantcompute, &dev->flags))
+ BUG_ON(++s.compute > 2);
-
- if (dev->toread)
+ if (test_bit(R5_Wantfill, &dev->flags)) {
+ s.to_fill++;
+ } else if (dev->toread)
s.to_read++;
if (dev->towrite) {
s.to_write++;
@@ -3106,6 +3252,11 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
blocked_rdev = NULL;
}
+ if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
+ set_bit(STRIPE_OP_BIOFILL, &s.ops_request);
+ set_bit(STRIPE_BIOFILL_RUN, &sh->state);
+ }
+
pr_debug("locked=%d uptodate=%d to_read=%d"
" to_write=%d failed=%d failed_num=%d,%d\n",
s.locked, s.uptodate, s.to_read, s.to_write, s.failed,
@@ -3146,19 +3297,62 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
* or to load a block that is being partially written.
*/
if (s.to_read || s.non_overwrite || (s.to_write && s.failed) ||
- (s.syncing && (s.uptodate < disks)) || s.expanding)
+ (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding)
handle_stripe_fill6(sh, &s, &r6s, disks);
- /* now to consider writing and what else, if anything should be read */
- if (s.to_write)
+ /* Now we check to see if any write operations have recently
+ * completed
+ */
+ if (sh->reconstruct_state == reconstruct_state_drain_result) {
+ int qd_idx = sh->qd_idx;
+
+ sh->reconstruct_state = reconstruct_state_idle;
+ /* All the 'written' buffers and the parity blocks are ready to
+ * be written back to disk
+ */
+ BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags));
+ BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[qd_idx].flags));
+ for (i = disks; i--; ) {
+ dev = &sh->dev[i];
+ if (test_bit(R5_LOCKED, &dev->flags) &&
+ (i == sh->pd_idx || i == qd_idx ||
+ dev->written)) {
+ pr_debug("Writing block %d\n", i);
+ BUG_ON(!test_bit(R5_UPTODATE, &dev->flags));
+ set_bit(R5_Wantwrite, &dev->flags);
+ if (!test_bit(R5_Insync, &dev->flags) ||
+ ((i == sh->pd_idx || i == qd_idx) &&
+ s.failed == 0))
+ set_bit(STRIPE_INSYNC, &sh->state);
+ }
+ }
+ if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) {
+ atomic_dec(&conf->preread_active_stripes);
+ if (atomic_read(&conf->preread_active_stripes) <
+ IO_THRESHOLD)
+ md_wakeup_thread(conf->mddev->thread);
+ }
+ }
+
+ /* Now to consider new write requests and what else, if anything
+ * should be read. We do not handle new writes when:
+ * 1/ A 'write' operation (copy+gen_syndrome) is already in flight.
+ * 2/ A 'check' operation is in flight, as it may clobber the parity
+ * block.
+ */
+ if (s.to_write && !sh->reconstruct_state && !sh->check_state)
handle_stripe_dirtying6(conf, sh, &s, &r6s, disks);
/* maybe we need to check and possibly fix the parity for this stripe
* Any reads will already have been scheduled, so we just see if enough
- * data is available
+ * data is available. The parity check is held off while parity
+ * dependent operations are in flight.
*/
- if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state))
- handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks);
+ if (sh->check_state ||
+ (s.syncing && s.locked == 0 &&
+ !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
+ !test_bit(STRIPE_INSYNC, &sh->state)))
+ handle_parity_checks6(conf, sh, &s, &r6s, disks);
if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) {
md_done_sync(conf->mddev, STRIPE_SECTORS,1);
@@ -3179,15 +3373,29 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
set_bit(R5_Wantwrite, &dev->flags);
set_bit(R5_ReWrite, &dev->flags);
set_bit(R5_LOCKED, &dev->flags);
+ s.locked++;
} else {
/* let's read it back */
set_bit(R5_Wantread, &dev->flags);
set_bit(R5_LOCKED, &dev->flags);
+ s.locked++;
}
}
}
- if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) {
+ /* Finish reconstruct operations initiated by the expansion process */
+ if (sh->reconstruct_state == reconstruct_state_result) {
+ sh->reconstruct_state = reconstruct_state_idle;
+ clear_bit(STRIPE_EXPANDING, &sh->state);
+ for (i = conf->raid_disks; i--; ) {
+ set_bit(R5_Wantwrite, &sh->dev[i].flags);
+ set_bit(R5_LOCKED, &sh->dev[i].flags);
+ s.locked++;
+ }
+ }
+
+ if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) &&
+ !sh->reconstruct_state) {
struct stripe_head *sh2
= get_active_stripe(conf, sh->sector, 1, 1, 1);
if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) {
@@ -3208,14 +3416,8 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
/* Need to write out all blocks after computing P&Q */
sh->disks = conf->raid_disks;
stripe_set_idx(sh->sector, conf, 0, sh);
- compute_parity6(sh, RECONSTRUCT_WRITE);
- for (i = conf->raid_disks ; i-- ; ) {
- set_bit(R5_LOCKED, &sh->dev[i].flags);
- s.locked++;
- set_bit(R5_Wantwrite, &sh->dev[i].flags);
- }
- clear_bit(STRIPE_EXPANDING, &sh->state);
- } else if (s.expanded) {
+ schedule_reconstruction(sh, &s, 1, 1);
+ } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
clear_bit(STRIPE_EXPAND_READY, &sh->state);
atomic_dec(&conf->reshape_stripes);
wake_up(&conf->wait_for_overlap);
@@ -3233,6 +3435,9 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
if (unlikely(blocked_rdev))
md_wait_for_blocked_rdev(blocked_rdev, conf->mddev);
+ if (s.ops_request)
+ raid_run_ops(sh, s.ops_request);
+
ops_run_io(sh, &s);
return_io(return_bi);
@@ -3241,16 +3446,14 @@ static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page)
}
/* returns true if the stripe was handled */
-static bool handle_stripe(struct stripe_head *sh, struct page *tmp_page)
+static bool handle_stripe(struct stripe_head *sh)
{
if (sh->raid_conf->level == 6)
- return handle_stripe6(sh, tmp_page);
+ return handle_stripe6(sh);
else
return handle_stripe5(sh);
}
-
-
static void raid5_activate_delayed(raid5_conf_t *conf)
{
if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
@@ -4046,7 +4249,7 @@ static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *ski
spin_unlock(&sh->lock);
/* wait for any blocked device to be handled */
- while(unlikely(!handle_stripe(sh, NULL)))
+ while (unlikely(!handle_stripe(sh)))
;
release_stripe(sh);
@@ -4103,7 +4306,7 @@ static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio)
return handled;
}
- handle_stripe(sh, NULL);
+ handle_stripe(sh);
release_stripe(sh);
handled++;
}
@@ -4117,6 +4320,36 @@ static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio)
return handled;
}
+#ifdef CONFIG_MULTICORE_RAID456
+static void __process_stripe(void *param, async_cookie_t cookie)
+{
+ struct stripe_head *sh = param;
+
+ handle_stripe(sh);
+ release_stripe(sh);
+}
+
+static void process_stripe(struct stripe_head *sh, struct list_head *domain)
+{
+ async_schedule_domain(__process_stripe, sh, domain);
+}
+
+static void synchronize_stripe_processing(struct list_head *domain)
+{
+ async_synchronize_full_domain(domain);
+}
+#else
+static void process_stripe(struct stripe_head *sh, struct list_head *domain)
+{
+ handle_stripe(sh);
+ release_stripe(sh);
+ cond_resched();
+}
+
+static void synchronize_stripe_processing(struct list_head *domain)
+{
+}
+#endif
/*
@@ -4131,6 +4364,7 @@ static void raid5d(mddev_t *mddev)
struct stripe_head *sh;
raid5_conf_t *conf = mddev_to_conf(mddev);
int handled;
+ LIST_HEAD(raid_domain);
pr_debug("+++ raid5d active\n");
@@ -4167,8 +4401,7 @@ static void raid5d(mddev_t *mddev)
spin_unlock_irq(&conf->device_lock);
handled++;
- handle_stripe(sh, conf->spare_page);
- release_stripe(sh);
+ process_stripe(sh, &raid_domain);
spin_lock_irq(&conf->device_lock);
}
@@ -4176,6 +4409,7 @@ static void raid5d(mddev_t *mddev)
spin_unlock_irq(&conf->device_lock);
+ synchronize_stripe_processing(&raid_domain);
async_tx_issue_pending_all();
unplug_slaves(mddev);
@@ -4308,6 +4542,118 @@ raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks)
return sectors * (raid_disks - conf->max_degraded);
}
+static void raid5_free_percpu(raid5_conf_t *conf)
+{
+ struct raid5_percpu *percpu;
+ unsigned long cpu;
+
+ if (!conf->percpu)
+ return;
+
+ get_online_cpus();
+ for_each_possible_cpu(cpu) {
+ percpu = per_cpu_ptr(conf->percpu, cpu);
+ safe_put_page(percpu->spare_page);
+ kfree(percpu->scribble);
+ }
+#ifdef CONFIG_HOTPLUG_CPU
+ unregister_cpu_notifier(&conf->cpu_notify);
+#endif
+ put_online_cpus();
+
+ free_percpu(conf->percpu);
+}
+
+static void free_conf(raid5_conf_t *conf)
+{
+ shrink_stripes(conf);
+ raid5_free_percpu(conf);
+ kfree(conf->disks);
+ kfree(conf->stripe_hashtbl);
+ kfree(conf);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
+ void *hcpu)
+{
+ raid5_conf_t *conf = container_of(nfb, raid5_conf_t, cpu_notify);
+ long cpu = (long)hcpu;
+ struct raid5_percpu *percpu = per_cpu_ptr(conf->percpu, cpu);
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
+ if (conf->level == 6 && !percpu->spare_page)
+ percpu->spare_page = alloc_page(GFP_KERNEL);
+ if (!percpu->scribble)
+ percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
+
+ if (!percpu->scribble ||
+ (conf->level == 6 && !percpu->spare_page)) {
+ safe_put_page(percpu->spare_page);
+ kfree(percpu->scribble);
+ pr_err("%s: failed memory allocation for cpu%ld\n",
+ __func__, cpu);
+ return NOTIFY_BAD;
+ }
+ break;
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ safe_put_page(percpu->spare_page);
+ kfree(percpu->scribble);
+ percpu->spare_page = NULL;
+ percpu->scribble = NULL;
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+#endif
+
+static int raid5_alloc_percpu(raid5_conf_t *conf)
+{
+ unsigned long cpu;
+ struct page *spare_page;
+ struct raid5_percpu *allcpus;
+ void *scribble;
+ int err;
+
+ allcpus = alloc_percpu(struct raid5_percpu);
+ if (!allcpus)
+ return -ENOMEM;
+ conf->percpu = allcpus;
+
+ get_online_cpus();
+ err = 0;
+ for_each_present_cpu(cpu) {
+ if (conf->level == 6) {
+ spare_page = alloc_page(GFP_KERNEL);
+ if (!spare_page) {
+ err = -ENOMEM;
+ break;
+ }
+ per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page;
+ }
+ scribble = kmalloc(scribble_len(conf->raid_disks), GFP_KERNEL);
+ if (!scribble) {
+ err = -ENOMEM;
+ break;
+ }
+ per_cpu_ptr(conf->percpu, cpu)->scribble = scribble;
+ }
+#ifdef CONFIG_HOTPLUG_CPU
+ conf->cpu_notify.notifier_call = raid456_cpu_notify;
+ conf->cpu_notify.priority = 0;
+ if (err == 0)
+ err = register_cpu_notifier(&conf->cpu_notify);
+#endif
+ put_online_cpus();
+
+ return err;
+}
+
static raid5_conf_t *setup_conf(mddev_t *mddev)
{
raid5_conf_t *conf;
@@ -4347,6 +4693,7 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
goto abort;
conf->raid_disks = mddev->raid_disks;
+ conf->scribble_len = scribble_len(conf->raid_disks);
if (mddev->reshape_position == MaxSector)
conf->previous_raid_disks = mddev->raid_disks;
else
@@ -4362,11 +4709,10 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL)
goto abort;
- if (mddev->new_level == 6) {
- conf->spare_page = alloc_page(GFP_KERNEL);
- if (!conf->spare_page)
- goto abort;
- }
+ conf->level = mddev->new_level;
+ if (raid5_alloc_percpu(conf) != 0)
+ goto abort;
+
spin_lock_init(&conf->device_lock);
init_waitqueue_head(&conf->wait_for_stripe);
init_waitqueue_head(&conf->wait_for_overlap);
@@ -4402,7 +4748,6 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
}
conf->chunk_size = mddev->new_chunk;
- conf->level = mddev->new_level;
if (conf->level == 6)
conf->max_degraded = 2;
else
@@ -4437,11 +4782,7 @@ static raid5_conf_t *setup_conf(mddev_t *mddev)
abort:
if (conf) {
- shrink_stripes(conf);
- safe_put_page(conf->spare_page);
- kfree(conf->disks);
- kfree(conf->stripe_hashtbl);
- kfree(conf);
+ free_conf(conf);
return ERR_PTR(-EIO);
} else
return ERR_PTR(-ENOMEM);
@@ -4607,12 +4948,8 @@ abort:
md_unregister_thread(mddev->thread);
mddev->thread = NULL;
if (conf) {
- shrink_stripes(conf);
print_raid5_conf(conf);
- safe_put_page(conf->spare_page);
- kfree(conf->disks);
- kfree(conf->stripe_hashtbl);
- kfree(conf);
+ free_conf(conf);
}
mddev->private = NULL;
printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev));
@@ -4627,13 +4964,10 @@ static int stop(mddev_t *mddev)
md_unregister_thread(mddev->thread);
mddev->thread = NULL;
- shrink_stripes(conf);
- kfree(conf->stripe_hashtbl);
mddev->queue->backing_dev_info.congested_fn = NULL;
blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
sysfs_remove_group(&mddev->kobj, &raid5_attrs_group);
- kfree(conf->disks);
- kfree(conf);
+ free_conf(conf);
mddev->private = NULL;
return 0;
}
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 52ba999..116d0b4 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -2,6 +2,7 @@
#define _RAID5_H
#include <linux/raid/xor.h>
+#include <linux/dmaengine.h>
/*
*
@@ -175,7 +176,9 @@
*/
enum check_states {
check_state_idle = 0,
- check_state_run, /* parity check */
+ check_state_run, /* xor parity check */
+ check_state_run_q, /* q-parity check */
+ check_state_run_pq, /* pq dual parity check */
check_state_check_result,
check_state_compute_run, /* parity repair */
check_state_compute_result,
@@ -215,8 +218,8 @@ struct stripe_head {
* @target - STRIPE_OP_COMPUTE_BLK target
*/
struct stripe_operations {
- int target;
- u32 zero_sum_result;
+ int target, target2;
+ enum sum_check_flags zero_sum_result;
} ops;
struct r5dev {
struct bio req;
@@ -298,7 +301,7 @@ struct r6_state {
#define STRIPE_OP_COMPUTE_BLK 1
#define STRIPE_OP_PREXOR 2
#define STRIPE_OP_BIODRAIN 3
-#define STRIPE_OP_POSTXOR 4
+#define STRIPE_OP_RECONSTRUCT 4
#define STRIPE_OP_CHECK 5
/*
@@ -383,8 +386,21 @@ struct raid5_private_data {
* (fresh device added).
* Cleared when a sync completes.
*/
-
- struct page *spare_page; /* Used when checking P/Q in raid6 */
+ /* per cpu variables */
+ struct raid5_percpu {
+ struct page *spare_page; /* Used when checking P/Q in raid6 */
+ void *scribble; /* space for constructing buffer
+ * lists and performing address
+ * conversions
+ */
+ } *percpu;
+ size_t scribble_len; /* size of scribble region must be
+ * associated with conf to handle
+ * cpu hotplug while reshaping
+ */
+#ifdef CONFIG_HOTPLUG_CPU
+ struct notifier_block cpu_notify;
+#endif
/*
* Free stripes pool
diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h
index 5fc2ef8..866e61c 100644
--- a/include/linux/async_tx.h
+++ b/include/linux/async_tx.h
@@ -58,25 +58,57 @@ struct dma_chan_ref {
* array.
* @ASYNC_TX_ACK: immediately ack the descriptor, precludes setting up a
* dependency chain
- * @ASYNC_TX_DEP_ACK: ack the dependency descriptor. Useful for chaining.
*/
enum async_tx_flags {
ASYNC_TX_XOR_ZERO_DST = (1 << 0),
ASYNC_TX_XOR_DROP_DST = (1 << 1),
- ASYNC_TX_ACK = (1 << 3),
- ASYNC_TX_DEP_ACK = (1 << 4),
+ ASYNC_TX_ACK = (1 << 2),
+};
+
+/**
+ * struct async_submit_ctl - async_tx submission/completion modifiers
+ * @flags: submission modifiers
+ * @depend_tx: parent dependency of the current operation being submitted
+ * @cb_fn: callback routine to run at operation completion
+ * @cb_param: parameter for the callback routine
+ * @scribble: caller provided space for dma/page address conversions
+ */
+struct async_submit_ctl {
+ enum async_tx_flags flags;
+ struct dma_async_tx_descriptor *depend_tx;
+ dma_async_tx_callback cb_fn;
+ void *cb_param;
+ void *scribble;
};
#ifdef CONFIG_DMA_ENGINE
#define async_tx_issue_pending_all dma_issue_pending_all
+
+/**
+ * async_tx_issue_pending - send pending descriptor to the hardware channel
+ * @tx: descriptor handle to retrieve hardware context
+ *
+ * Note: any dependent operations will have already been issued by
+ * async_tx_channel_switch, or (in the case of no channel switch) will
+ * be already pending on this channel.
+ */
+static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
+{
+ if (likely(tx)) {
+ struct dma_chan *chan = tx->chan;
+ struct dma_device *dma = chan->device;
+
+ dma->device_issue_pending(chan);
+ }
+}
#ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
#include <asm/async_tx.h>
#else
#define async_tx_find_channel(dep, type, dst, dst_count, src, src_count, len) \
__async_tx_find_channel(dep, type)
struct dma_chan *
-__async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
- enum dma_transaction_type tx_type);
+__async_tx_find_channel(struct async_submit_ctl *submit,
+ enum dma_transaction_type tx_type);
#endif /* CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL */
#else
static inline void async_tx_issue_pending_all(void)
@@ -84,10 +116,16 @@ static inline void async_tx_issue_pending_all(void)
do { } while (0);
}
+static inline void async_tx_issue_pending(struct dma_async_tx_descriptor *tx)
+{
+ do { } while (0);
+}
+
static inline struct dma_chan *
-async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
- enum dma_transaction_type tx_type, struct page **dst, int dst_count,
- struct page **src, int src_count, size_t len)
+async_tx_find_channel(struct async_submit_ctl *submit,
+ enum dma_transaction_type tx_type, struct page **dst,
+ int dst_count, struct page **src, int src_count,
+ size_t len)
{
return NULL;
}
@@ -99,46 +137,70 @@ async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
* @cb_fn_param: parameter to pass to the callback routine
*/
static inline void
-async_tx_sync_epilog(dma_async_tx_callback cb_fn, void *cb_fn_param)
+async_tx_sync_epilog(struct async_submit_ctl *submit)
{
- if (cb_fn)
- cb_fn(cb_fn_param);
+ if (submit->cb_fn)
+ submit->cb_fn(submit->cb_param);
}
-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 cb_fn, void *cb_fn_param);
+typedef union {
+ unsigned long addr;
+ struct page *page;
+ dma_addr_t dma;
+} addr_conv_t;
+
+static inline void
+init_async_submit(struct async_submit_ctl *args, enum async_tx_flags flags,
+ struct dma_async_tx_descriptor *tx,
+ dma_async_tx_callback cb_fn, void *cb_param,
+ addr_conv_t *scribble)
+{
+ args->flags = flags;
+ args->depend_tx = tx;
+ args->cb_fn = cb_fn;
+ args->cb_param = cb_param;
+ args->scribble = scribble;
+}
+
+void async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
+ struct async_submit_ctl *submit);
struct dma_async_tx_descriptor *
async_xor(struct page *dest, struct page **src_list, unsigned int offset,
- int src_cnt, size_t len, enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_fn_param);
+ int src_cnt, size_t len, struct async_submit_ctl *submit);
struct dma_async_tx_descriptor *
-async_xor_zero_sum(struct page *dest, struct page **src_list,
- unsigned int offset, int src_cnt, size_t len,
- u32 *result, enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_fn_param);
+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_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 cb_fn, void *cb_fn_param);
+ unsigned int src_offset, size_t len,
+ struct async_submit_ctl *submit);
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 cb_fn, void *cb_fn_param);
+ size_t len, struct async_submit_ctl *submit);
+
+struct dma_async_tx_descriptor *async_trigger_callback(struct async_submit_ctl *submit);
+
+struct dma_async_tx_descriptor *
+async_gen_syndrome(struct page **blocks, unsigned int offset, int src_cnt,
+ size_t len, struct async_submit_ctl *submit);
+
+struct dma_async_tx_descriptor *
+async_syndrome_val(struct page **blocks, unsigned int offset, int src_cnt,
+ size_t len, enum sum_check_flags *pqres, struct page *spare,
+ struct async_submit_ctl *submit);
+
+struct dma_async_tx_descriptor *
+async_raid6_2data_recov(int src_num, size_t bytes, int faila, int failb,
+ struct page **ptrs, struct async_submit_ctl *submit);
struct dma_async_tx_descriptor *
-async_trigger_callback(enum async_tx_flags flags,
- struct dma_async_tx_descriptor *depend_tx,
- dma_async_tx_callback cb_fn, void *cb_fn_param);
+async_raid6_datap_recov(int src_num, size_t bytes, int faila,
+ struct page **ptrs, struct async_submit_ctl *submit);
void async_tx_quiesce(struct dma_async_tx_descriptor **tx);
#endif /* _ASYNC_TX_H_ */
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index ffefba8..1012f1a 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -52,11 +52,11 @@ enum dma_status {
enum dma_transaction_type {
DMA_MEMCPY,
DMA_XOR,
- DMA_PQ_XOR,
+ DMA_PQ,
DMA_DUAL_XOR,
DMA_PQ_UPDATE,
- DMA_ZERO_SUM,
- DMA_PQ_ZERO_SUM,
+ DMA_XOR_VAL,
+ DMA_PQ_VAL,
DMA_MEMSET,
DMA_MEMCPY_CRC32C,
DMA_INTERRUPT,
@@ -70,18 +70,23 @@ enum dma_transaction_type {
/**
* enum dma_ctrl_flags - DMA flags to augment operation preparation,
- * control completion, and communicate status.
+ * control completion, and communicate status.
* @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
- * this transaction
+ * this transaction
* @DMA_CTRL_ACK - the descriptor cannot be reused until the client
- * acknowledges receipt, i.e. has has a chance to establish any
- * dependency chains
+ * acknowledges receipt, i.e. has has a chance to establish any dependency
+ * chains
* @DMA_COMPL_SKIP_SRC_UNMAP - set to disable dma-unmapping the source buffer(s)
* @DMA_COMPL_SKIP_DEST_UNMAP - set to disable dma-unmapping the destination(s)
* @DMA_COMPL_SRC_UNMAP_SINGLE - set to do the source dma-unmapping as single
* (if not set, do the source dma-unmapping as page)
* @DMA_COMPL_DEST_UNMAP_SINGLE - set to do the destination dma-unmapping as single
* (if not set, do the destination dma-unmapping as page)
+ * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
+ * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
+ * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
+ * sources that were the result of a previous operation, in the case of a PQ
+ * operation it continues the calculation with new sources
*/
enum dma_ctrl_flags {
DMA_PREP_INTERRUPT = (1 << 0),
@@ -90,9 +95,31 @@ enum dma_ctrl_flags {
DMA_COMPL_SKIP_DEST_UNMAP = (1 << 3),
DMA_COMPL_SRC_UNMAP_SINGLE = (1 << 4),
DMA_COMPL_DEST_UNMAP_SINGLE = (1 << 5),
+ DMA_PREP_PQ_DISABLE_P = (1 << 6),
+ DMA_PREP_PQ_DISABLE_Q = (1 << 7),
+ DMA_PREP_CONTINUE = (1 << 8),
};
/**
+ * enum sum_check_bits - bit position of pq_check_flags
+ */
+enum sum_check_bits {
+ SUM_CHECK_P = 0,
+ SUM_CHECK_Q = 1,
+};
+
+/**
+ * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
+ * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
+ * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
+ */
+enum sum_check_flags {
+ SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
+ SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
+};
+
+
+/**
* dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
* See linux/cpumask.h
*/
@@ -213,6 +240,7 @@ struct dma_async_tx_descriptor {
* @global_node: list_head for global dma_device_list
* @cap_mask: one or more dma_capability flags
* @max_xor: maximum number of xor sources, 0 if no capability
+ * @max_pq: maximum number of PQ sources and PQ-continue capability
* @dev_id: unique device ID
* @dev: struct device reference for dma mapping api
* @device_alloc_chan_resources: allocate resources and return the
@@ -220,7 +248,9 @@ struct dma_async_tx_descriptor {
* @device_free_chan_resources: release DMA channel's resources
* @device_prep_dma_memcpy: prepares a memcpy operation
* @device_prep_dma_xor: prepares a xor operation
- * @device_prep_dma_zero_sum: prepares a zero_sum operation
+ * @device_prep_dma_xor_val: prepares a xor validation operation
+ * @device_prep_dma_pq: prepares a pq operation
+ * @device_prep_dma_pq_val: prepares a pqzero_sum operation
* @device_prep_dma_memset: prepares a memset operation
* @device_prep_dma_interrupt: prepares an end of chain interrupt operation
* @device_prep_slave_sg: prepares a slave dma operation
@@ -235,7 +265,9 @@ struct dma_device {
struct list_head channels;
struct list_head global_node;
dma_cap_mask_t cap_mask;
- int max_xor;
+ unsigned short max_xor;
+ unsigned short max_pq;
+ #define DMA_HAS_PQ_CONTINUE (1 << 15)
int dev_id;
struct device *dev;
@@ -249,9 +281,17 @@ struct dma_device {
struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
unsigned int src_cnt, size_t len, unsigned long flags);
- struct dma_async_tx_descriptor *(*device_prep_dma_zero_sum)(
+ struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
- size_t len, u32 *result, unsigned long flags);
+ size_t len, enum sum_check_flags *result, unsigned long flags);
+ struct dma_async_tx_descriptor *(*device_prep_dma_pq)(
+ struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
+ unsigned int src_cnt, const unsigned char *scf,
+ size_t len, unsigned long flags);
+ struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)(
+ struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
+ unsigned int src_cnt, const unsigned char *scf, size_t len,
+ enum sum_check_flags *pqres, unsigned long flags);
struct dma_async_tx_descriptor *(*device_prep_dma_memset)(
struct dma_chan *chan, dma_addr_t dest, int value, size_t len,
unsigned long flags);
@@ -270,6 +310,60 @@ struct dma_device {
void (*device_issue_pending)(struct dma_chan *chan);
};
+static inline void
+dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
+{
+ dma->max_pq = maxpq;
+ if (has_pq_continue)
+ dma->max_pq |= DMA_HAS_PQ_CONTINUE;
+}
+
+static inline bool dmaf_continue(enum dma_ctrl_flags flags)
+{
+ return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
+}
+
+static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
+{
+ enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;
+
+ return (flags & mask) == mask;
+}
+
+static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
+{
+ return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
+}
+
+static unsigned short dma_dev_to_maxpq(struct dma_device *dma)
+{
+ return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
+}
+
+/* dma_maxpq - reduce maxpq in the face of continued operations
+ * @dma - dma device with PQ capability
+ * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
+ *
+ * When an engine does not support native continuation we need 3 extra
+ * source slots to reuse P and Q with the following coefficients:
+ * 1/ {00} * P : remove P from Q', but use it as a source for P'
+ * 2/ {01} * Q : use Q to continue Q' calculation
+ * 3/ {00} * Q : subtract Q from P' to cancel (2)
+ *
+ * In the case where P is disabled we only need 1 extra source:
+ * 1/ {01} * Q : use Q to continue Q' calculation
+ */
+static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
+{
+ if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
+ return dma_dev_to_maxpq(dma);
+ else if (dmaf_p_disabled_continue(flags))
+ return dma_dev_to_maxpq(dma) - 1;
+ else if (dmaf_continue(flags))
+ return dma_dev_to_maxpq(dma) - 3;
+ BUG();
+}
+
/* --- public DMA engine API --- */
#ifdef CONFIG_DMA_ENGINE
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