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-rw-r--r--crypto/async_tx/Kconfig5
-rw-r--r--crypto/async_tx/async_pq.c75
-rw-r--r--crypto/async_tx/async_raid6_recov.c121
-rw-r--r--crypto/async_tx/async_tx.c46
-rw-r--r--crypto/async_tx/async_xor.c33
-rw-r--r--crypto/async_tx/raid6test.c8
6 files changed, 182 insertions, 106 deletions
diff --git a/crypto/async_tx/Kconfig b/crypto/async_tx/Kconfig
index e24aa80..5de2ed1 100644
--- a/crypto/async_tx/Kconfig
+++ b/crypto/async_tx/Kconfig
@@ -37,3 +37,8 @@ config ASYNC_RAID6_TEST
If unsure, say N.
+config ASYNC_TX_DISABLE_PQ_VAL_DMA
+ bool
+
+config ASYNC_TX_DISABLE_XOR_VAL_DMA
+ bool
diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c
index b88db6d..fdd8257 100644
--- a/crypto/async_tx/async_pq.c
+++ b/crypto/async_tx/async_pq.c
@@ -24,16 +24,13 @@
#include <linux/dma-mapping.h>
#include <linux/raid/pq.h>
#include <linux/async_tx.h>
+#include <linux/gfp.h>
/**
- * scribble - space to hold throwaway P buffer for synchronous gen_syndrome
+ * pq_scribble_page - space to hold throwaway P or Q 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;
-}
+static struct page *pq_scribble_page;
/* the struct page *blocks[] parameter passed to async_gen_syndrome()
* and async_syndrome_val() contains the 'P' destination address at
@@ -83,7 +80,7 @@ do_async_gen_syndrome(struct dma_chan *chan, struct page **blocks,
* sources and update the coefficients accordingly
*/
for (i = 0, idx = 0; i < src_cnt; i++) {
- if (is_raid6_zero_block(blocks[i]))
+ if (blocks[i] == NULL)
continue;
dma_src[idx] = dma_map_page(dma->dev, blocks[i], offset, len,
DMA_TO_DEVICE);
@@ -160,9 +157,9 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
srcs = (void **) blocks;
for (i = 0; i < disks; i++) {
- if (is_raid6_zero_block(blocks[i])) {
+ if (blocks[i] == NULL) {
BUG_ON(i > disks - 3); /* P or Q can't be zero */
- srcs[i] = blocks[i];
+ srcs[i] = (void*)raid6_empty_zero_page;
} else
srcs[i] = page_address(blocks[i]) + offset;
}
@@ -186,10 +183,14 @@ do_sync_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
* 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.
+ * buffers. If any source buffers (blocks[i] where i < disks - 2) are
+ * set to NULL those buffers will be replaced with the raid6_zero_page
+ * in the synchronous path and omitted in the hardware-asynchronous
+ * path.
*
* 'blocks' note: if submit->scribble is NULL then the contents of
- * 'blocks' may be overridden
+ * 'blocks' may be overwritten to perform address conversions
+ * (dma_map_page() or page_address()).
*/
struct dma_async_tx_descriptor *
async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
@@ -227,11 +228,11 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
async_tx_quiesce(&submit->depend_tx);
if (!P(blocks, disks)) {
- P(blocks, disks) = scribble;
+ P(blocks, disks) = pq_scribble_page;
BUG_ON(len + offset > PAGE_SIZE);
}
if (!Q(blocks, disks)) {
- Q(blocks, disks) = scribble;
+ Q(blocks, disks) = pq_scribble_page;
BUG_ON(len + offset > PAGE_SIZE);
}
do_sync_gen_syndrome(blocks, offset, disks, len, submit);
@@ -240,6 +241,16 @@ async_gen_syndrome(struct page **blocks, unsigned int offset, int disks,
}
EXPORT_SYMBOL_GPL(async_gen_syndrome);
+static inline struct dma_chan *
+pq_val_chan(struct async_submit_ctl *submit, struct page **blocks, int disks, size_t len)
+{
+ #ifdef CONFIG_ASYNC_TX_DISABLE_PQ_VAL_DMA
+ return NULL;
+ #endif
+ return async_tx_find_channel(submit, DMA_PQ_VAL, NULL, 0, blocks,
+ disks, len);
+}
+
/**
* async_syndrome_val - asynchronously validate a raid6 syndrome
* @blocks: source blocks from idx 0..disks-3, P @ disks-2 and Q @ disks-1
@@ -260,13 +271,13 @@ 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_chan *chan = pq_val_chan(submit, blocks, disks, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx;
+ unsigned char coefs[disks-2];
enum dma_ctrl_flags dma_flags = submit->cb_fn ? DMA_PREP_INTERRUPT : 0;
dma_addr_t *dma_src = NULL;
+ int src_cnt = 0;
BUG_ON(disks < 4);
@@ -285,22 +296,32 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int disks,
__func__, disks, len);
if (!P(blocks, disks))
dma_flags |= DMA_PREP_PQ_DISABLE_P;
+ else
+ pq[0] = dma_map_page(dev, P(blocks, disks),
+ offset, len,
+ DMA_TO_DEVICE);
if (!Q(blocks, disks))
dma_flags |= DMA_PREP_PQ_DISABLE_Q;
+ else
+ pq[1] = dma_map_page(dev, Q(blocks, disks),
+ offset, len,
+ DMA_TO_DEVICE);
+
if (submit->flags & ASYNC_TX_FENCE)
dma_flags |= DMA_PREP_FENCE;
- for (i = 0; i < disks; i++)
+ for (i = 0; i < disks-2; 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);
+ dma_src[src_cnt] = dma_map_page(dev, blocks[i],
+ offset, len,
+ DMA_TO_DEVICE);
+ coefs[src_cnt] = raid6_gfexp[i];
+ src_cnt++;
}
for (;;) {
tx = device->device_prep_dma_pq_val(chan, pq, dma_src,
- disks - 2,
- raid6_gfexp,
+ src_cnt,
+ coefs,
len, pqres,
dma_flags);
if (likely(tx))
@@ -373,9 +394,9 @@ EXPORT_SYMBOL_GPL(async_syndrome_val);
static int __init async_pq_init(void)
{
- scribble = alloc_page(GFP_KERNEL);
+ pq_scribble_page = alloc_page(GFP_KERNEL);
- if (scribble)
+ if (pq_scribble_page)
return 0;
pr_err("%s: failed to allocate required spare page\n", __func__);
@@ -385,7 +406,7 @@ static int __init async_pq_init(void)
static void __exit async_pq_exit(void)
{
- put_page(scribble);
+ put_page(pq_scribble_page);
}
module_init(async_pq_init);
diff --git a/crypto/async_tx/async_raid6_recov.c b/crypto/async_tx/async_raid6_recov.c
index 6d73dde..ce038d8 100644
--- a/crypto/async_tx/async_raid6_recov.c
+++ b/crypto/async_tx/async_raid6_recov.c
@@ -131,8 +131,8 @@ async_mult(struct page *dest, struct page *src, u8 coef, size_t len,
}
static struct dma_async_tx_descriptor *
-__2data_recov_4(size_t bytes, int faila, int failb, struct page **blocks,
- struct async_submit_ctl *submit)
+__2data_recov_4(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
{
struct dma_async_tx_descriptor *tx = NULL;
struct page *p, *q, *a, *b;
@@ -143,8 +143,8 @@ __2data_recov_4(size_t bytes, int faila, int failb, struct page **blocks,
void *cb_param = submit->cb_param;
void *scribble = submit->scribble;
- p = blocks[4-2];
- q = blocks[4-1];
+ p = blocks[disks-2];
+ q = blocks[disks-1];
a = blocks[faila];
b = blocks[failb];
@@ -170,8 +170,8 @@ __2data_recov_4(size_t bytes, int faila, int failb, struct page **blocks,
}
static struct dma_async_tx_descriptor *
-__2data_recov_5(size_t bytes, int faila, int failb, struct page **blocks,
- struct async_submit_ctl *submit)
+__2data_recov_5(int disks, size_t bytes, int faila, int failb,
+ struct page **blocks, struct async_submit_ctl *submit)
{
struct dma_async_tx_descriptor *tx = NULL;
struct page *p, *q, *g, *dp, *dq;
@@ -181,21 +181,22 @@ __2data_recov_5(size_t bytes, int faila, int failb, struct page **blocks,
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;
+ int good_srcs, good, i;
- for (i = 0; i < 3; i++) {
+ good_srcs = 0;
+ good = -1;
+ for (i = 0; i < disks-2; i++) {
+ if (blocks[i] == NULL)
+ continue;
if (i == faila || i == failb)
continue;
- else {
- good = i;
- break;
- }
+ good = i;
+ good_srcs++;
}
- BUG_ON(i >= 3);
+ BUG_ON(good_srcs > 1);
- p = blocks[5-2];
- q = blocks[5-1];
+ p = blocks[disks-2];
+ q = blocks[disks-1];
g = blocks[good];
/* Compute syndrome with zero for the missing data pages
@@ -263,10 +264,10 @@ __2data_recov_n(int disks, size_t bytes, int faila, int failb,
* delta p and delta q
*/
dp = blocks[faila];
- blocks[faila] = (void *)raid6_empty_zero_page;
+ blocks[faila] = NULL;
blocks[disks-2] = dp;
dq = blocks[failb];
- blocks[failb] = (void *)raid6_empty_zero_page;
+ blocks[failb] = NULL;
blocks[disks-1] = dq;
init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL, scribble);
@@ -323,22 +324,29 @@ struct dma_async_tx_descriptor *
async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
struct page **blocks, struct async_submit_ctl *submit)
{
+ void *scribble = submit->scribble;
+ int non_zero_srcs, i;
+
BUG_ON(faila == failb);
if (failb < faila)
swap(faila, failb);
pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
- /* we need to preserve the contents of 'blocks' for the async
- * case, so punt to synchronous if a scribble buffer is not available
+ /* if a dma resource is not available or a scribble buffer is not
+ * available punt to the synchronous path. In the 'dma not
+ * available' case be sure to use the scribble buffer to
+ * preserve the content of 'blocks' as the caller intended.
*/
- if (!submit->scribble) {
- void **ptrs = (void **) blocks;
- int i;
+ if (!async_dma_find_channel(DMA_PQ) || !scribble) {
+ void **ptrs = scribble ? scribble : (void **) blocks;
async_tx_quiesce(&submit->depend_tx);
for (i = 0; i < disks; i++)
- ptrs[i] = page_address(blocks[i]);
+ if (blocks[i] == NULL)
+ ptrs[i] = (void *) raid6_empty_zero_page;
+ else
+ ptrs[i] = page_address(blocks[i]);
raid6_2data_recov(disks, bytes, faila, failb, ptrs);
@@ -347,19 +355,30 @@ async_raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
return NULL;
}
- switch (disks) {
- case 4:
+ non_zero_srcs = 0;
+ for (i = 0; i < disks-2 && non_zero_srcs < 4; i++)
+ if (blocks[i])
+ non_zero_srcs++;
+ switch (non_zero_srcs) {
+ case 0:
+ case 1:
+ /* There must be at least 2 sources - the failed devices. */
+ BUG();
+
+ case 2:
/* dma devices do not uniformly understand a zero source pq
* operation (in contrast to the synchronous case), so
- * explicitly handle the 4 disk special case
+ * explicitly handle the special case of a 4 disk array with
+ * both data disks missing.
*/
- return __2data_recov_4(bytes, faila, failb, blocks, submit);
- case 5:
+ return __2data_recov_4(disks, bytes, faila, failb, blocks, submit);
+ case 3:
/* dma devices do not uniformly understand a single
* source pq operation (in contrast to the synchronous
- * case), so explicitly handle the 5 disk special case
+ * case), so explicitly handle the special case of a 5 disk
+ * array with 2 of 3 data disks missing.
*/
- return __2data_recov_5(bytes, faila, failb, blocks, submit);
+ return __2data_recov_5(disks, bytes, faila, failb, blocks, submit);
default:
return __2data_recov_n(disks, bytes, faila, failb, blocks, submit);
}
@@ -385,20 +404,25 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
dma_async_tx_callback cb_fn = submit->cb_fn;
void *cb_param = submit->cb_param;
void *scribble = submit->scribble;
+ int good_srcs, good, i;
struct page *srcs[2];
pr_debug("%s: disks: %d len: %zu\n", __func__, disks, bytes);
- /* we need to preserve the contents of 'blocks' for the async
- * case, so punt to synchronous if a scribble buffer is not available
+ /* if a dma resource is not available or a scribble buffer is not
+ * available punt to the synchronous path. In the 'dma not
+ * available' case be sure to use the scribble buffer to
+ * preserve the content of 'blocks' as the caller intended.
*/
- if (!scribble) {
- void **ptrs = (void **) blocks;
- int i;
+ if (!async_dma_find_channel(DMA_PQ) || !scribble) {
+ void **ptrs = scribble ? scribble : (void **) blocks;
async_tx_quiesce(&submit->depend_tx);
for (i = 0; i < disks; i++)
- ptrs[i] = page_address(blocks[i]);
+ if (blocks[i] == NULL)
+ ptrs[i] = (void*)raid6_empty_zero_page;
+ else
+ ptrs[i] = page_address(blocks[i]);
raid6_datap_recov(disks, bytes, faila, ptrs);
@@ -407,6 +431,20 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
return NULL;
}
+ good_srcs = 0;
+ good = -1;
+ for (i = 0; i < disks-2; i++) {
+ if (i == faila)
+ continue;
+ if (blocks[i]) {
+ good = i;
+ good_srcs++;
+ if (good_srcs > 1)
+ break;
+ }
+ }
+ BUG_ON(good_srcs == 0);
+
p = blocks[disks-2];
q = blocks[disks-1];
@@ -414,14 +452,13 @@ async_raid6_datap_recov(int disks, size_t bytes, int faila,
* Use the dead data page as temporary storage for delta q
*/
dq = blocks[faila];
- blocks[faila] = (void *)raid6_empty_zero_page;
+ blocks[faila] = NULL;
blocks[disks-1] = dq;
- /* in the 4 disk case we only need to perform a single source
- * multiplication
+ /* in the 4-disk case we only need to perform a single source
+ * multiplication with the one good data block.
*/
- if (disks == 4) {
- int good = faila == 0 ? 1 : 0;
+ if (good_srcs == 1) {
struct page *g = blocks[good];
init_async_submit(submit, ASYNC_TX_FENCE, tx, NULL, NULL,
diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c
index f9cdf04..7f2c00a 100644
--- a/crypto/async_tx/async_tx.c
+++ b/crypto/async_tx/async_tx.c
@@ -81,18 +81,13 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
struct dma_device *device = chan->device;
struct dma_async_tx_descriptor *intr_tx = (void *) ~0;
- #ifdef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH
- BUG();
- #endif
-
/* first check to see if we can still append to depend_tx */
- spin_lock_bh(&depend_tx->lock);
- if (depend_tx->parent && depend_tx->chan == tx->chan) {
- tx->parent = depend_tx;
- depend_tx->next = tx;
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx) && depend_tx->chan == tx->chan) {
+ txd_chain(depend_tx, tx);
intr_tx = NULL;
}
- spin_unlock_bh(&depend_tx->lock);
+ txd_unlock(depend_tx);
/* attached dependency, flush the parent channel */
if (!intr_tx) {
@@ -111,24 +106,22 @@ async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
if (intr_tx) {
intr_tx->callback = NULL;
intr_tx->callback_param = NULL;
- tx->parent = intr_tx;
- /* safe to set ->next outside the lock since we know we are
+ /* safe to chain outside the lock since we know we are
* not submitted yet
*/
- intr_tx->next = tx;
+ txd_chain(intr_tx, tx);
/* check if we need to append */
- spin_lock_bh(&depend_tx->lock);
- if (depend_tx->parent) {
- intr_tx->parent = depend_tx;
- depend_tx->next = intr_tx;
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx)) {
+ txd_chain(depend_tx, intr_tx);
async_tx_ack(intr_tx);
intr_tx = NULL;
}
- spin_unlock_bh(&depend_tx->lock);
+ txd_unlock(depend_tx);
if (intr_tx) {
- intr_tx->parent = NULL;
+ txd_clear_parent(intr_tx);
intr_tx->tx_submit(intr_tx);
async_tx_ack(intr_tx);
}
@@ -176,21 +169,20 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
* 2/ dependencies are 1:1 i.e. two transactions can
* not depend on the same parent
*/
- BUG_ON(async_tx_test_ack(depend_tx) || depend_tx->next ||
- tx->parent);
+ BUG_ON(async_tx_test_ack(depend_tx) || txd_next(depend_tx) ||
+ txd_parent(tx));
/* the lock prevents async_tx_run_dependencies from missing
* the setting of ->next when ->parent != NULL
*/
- spin_lock_bh(&depend_tx->lock);
- if (depend_tx->parent) {
+ txd_lock(depend_tx);
+ if (txd_parent(depend_tx)) {
/* we have a parent so we can not submit directly
* if we are staying on the same channel: append
* else: channel switch
*/
if (depend_tx->chan == chan) {
- tx->parent = depend_tx;
- depend_tx->next = tx;
+ txd_chain(depend_tx, tx);
s = ASYNC_TX_SUBMITTED;
} else
s = ASYNC_TX_CHANNEL_SWITCH;
@@ -203,7 +195,7 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
else
s = ASYNC_TX_CHANNEL_SWITCH;
}
- spin_unlock_bh(&depend_tx->lock);
+ txd_unlock(depend_tx);
switch (s) {
case ASYNC_TX_SUBMITTED:
@@ -212,12 +204,12 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
async_tx_channel_switch(depend_tx, tx);
break;
case ASYNC_TX_DIRECT_SUBMIT:
- tx->parent = NULL;
+ txd_clear_parent(tx);
tx->tx_submit(tx);
break;
}
} else {
- tx->parent = NULL;
+ txd_clear_parent(tx);
tx->tx_submit(tx);
}
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index b459a90..079ae8c 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -44,20 +44,23 @@ do_async_xor(struct dma_chan *chan, struct page *dest, struct page **src_list,
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;
+ int xor_src_cnt = 0;
dma_addr_t dma_dest;
/* map the dest bidrectional in case it is re-used as a source */
dma_dest = dma_map_page(dma->dev, dest, offset, len, DMA_BIDIRECTIONAL);
for (i = 0; i < src_cnt; i++) {
/* only map the dest once */
+ if (!src_list[i])
+ continue;
if (unlikely(src_list[i] == dest)) {
- dma_src[i] = dma_dest;
+ dma_src[xor_src_cnt++] = dma_dest;
continue;
}
- dma_src[i] = dma_map_page(dma->dev, src_list[i], offset,
- len, DMA_TO_DEVICE);
+ dma_src[xor_src_cnt++] = dma_map_page(dma->dev, src_list[i], offset,
+ len, DMA_TO_DEVICE);
}
+ src_cnt = xor_src_cnt;
while (src_cnt) {
submit->flags = flags_orig;
@@ -123,7 +126,7 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
int src_cnt, size_t len, struct async_submit_ctl *submit)
{
int i;
- int xor_src_cnt;
+ int xor_src_cnt = 0;
int src_off = 0;
void *dest_buf;
void **srcs;
@@ -135,8 +138,9 @@ do_sync_xor(struct page *dest, struct page **src_list, unsigned int offset,
/* convert to buffer pointers */
for (i = 0; i < src_cnt; i++)
- srcs[i] = page_address(src_list[i]) + offset;
-
+ if (src_list[i])
+ srcs[xor_src_cnt++] = page_address(src_list[i]) + offset;
+ src_cnt = xor_src_cnt;
/* set destination address */
dest_buf = page_address(dest) + offset;
@@ -230,6 +234,17 @@ static int page_is_zero(struct page *p, unsigned int offset, size_t len)
memcmp(a, a + 4, len - 4) == 0);
}
+static inline struct dma_chan *
+xor_val_chan(struct async_submit_ctl *submit, struct page *dest,
+ struct page **src_list, int src_cnt, size_t len)
+{
+ #ifdef CONFIG_ASYNC_TX_DISABLE_XOR_VAL_DMA
+ return NULL;
+ #endif
+ return async_tx_find_channel(submit, DMA_XOR_VAL, &dest, 1, src_list,
+ src_cnt, len);
+}
+
/**
* async_xor_val - attempt a xor parity check with a dma engine.
* @dest: destination page used if the xor is performed synchronously
@@ -251,9 +266,7 @@ 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(submit, DMA_XOR_VAL,
- &dest, 1, src_list,
- src_cnt, len);
+ struct dma_chan *chan = xor_val_chan(submit, dest, src_list, src_cnt, len);
struct dma_device *device = chan ? chan->device : NULL;
struct dma_async_tx_descriptor *tx = NULL;
dma_addr_t *dma_src = NULL;
diff --git a/crypto/async_tx/raid6test.c b/crypto/async_tx/raid6test.c
index 3ec27c7..c132193 100644
--- a/crypto/async_tx/raid6test.c
+++ b/crypto/async_tx/raid6test.c
@@ -20,6 +20,7 @@
*
*/
#include <linux/async_tx.h>
+#include <linux/gfp.h>
#include <linux/random.h>
#undef pr
@@ -214,6 +215,13 @@ static int raid6_test(void)
err += test(4, &tests);
if (NDISKS > 5)
err += test(5, &tests);
+ /* the 11 and 12 disk cases are special for ioatdma (p-disabled
+ * q-continuation without extended descriptor)
+ */
+ if (NDISKS > 12) {
+ err += test(11, &tests);
+ err += test(12, &tests);
+ }
err += test(NDISKS, &tests);
pr("\n");