The patch titled
async_tx: fix kmap_atomic usage in async_memcpy
has been added to the -mm tree. Its filename is
async_tx-fix-kmap_atomic-usage-in-async_memcpy.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: async_tx: fix kmap_atomic usage in async_memcpy
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Andrew Morton:
[async_memcpy] is very wrong if both ASYNC_TX_KMAP_DST and
ASYNC_TX_KMAP_SRC can ever be set. We'll end up using the same kmap
slot for both src add dest and we get either corrupted data or a BUG.
Evgeniy Polyakov:
Btw, shouldn't it always be kmap_atomic() even if flag is not set.
That pages are usual one returned by alloc_page().
So fix the usage of kmap_atomic and kill the ASYNC_TX_KMAP_DST and
ASYNC_TX_KMAP_SRC flags.
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Evgeniy Polyakov <johnpol@xxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
crypto/async_tx/async_memcpy.c | 19 ++++---------------
drivers/md/raid5.c | 4 ++--
include/linux/async_tx.h | 6 ------
3 files changed, 6 insertions(+), 23 deletions(-)
diff -puN crypto/async_tx/async_memcpy.c~async_tx-fix-kmap_atomic-usage-in-async_memcpy crypto/async_tx/async_memcpy.c
--- a/crypto/async_tx/async_memcpy.c~async_tx-fix-kmap_atomic-usage-in-async_memcpy
+++ a/crypto/async_tx/async_memcpy.c
@@ -36,7 +36,6 @@
* @offset: offset in pages to start transaction
* @len: length in bytes
* @flags: ASYNC_TX_ASSUME_COHERENT, ASYNC_TX_ACK, ASYNC_TX_DEP_ACK,
- * ASYNC_TX_KMAP_SRC, ASYNC_TX_KMAP_DST
* @depend_tx: memcpy depends on the result of this transaction
* @cb_fn: function to call when the memcpy completes
* @cb_param: parameter to pass to the callback routine
@@ -88,23 +87,13 @@ async_memcpy(struct page *dest, struct p
__FUNCTION__);
}
- if (flags & ASYNC_TX_KMAP_DST)
- dest_buf = kmap_atomic(dest, KM_USER0) + dest_offset;
- else
- dest_buf = page_address(dest) + dest_offset;
-
- if (flags & ASYNC_TX_KMAP_SRC)
- src_buf = kmap_atomic(src, KM_USER0) + src_offset;
- else
- src_buf = page_address(src) + src_offset;
+ dest_buf = kmap_atomic(dest, KM_USER0) + dest_offset;
+ src_buf = kmap_atomic(src, KM_USER1) + src_offset;
memcpy(dest_buf, src_buf, len);
- if (flags & ASYNC_TX_KMAP_DST)
- kunmap_atomic(dest_buf, KM_USER0);
-
- if (flags & ASYNC_TX_KMAP_SRC)
- kunmap_atomic(src_buf, KM_USER0);
+ kunmap_atomic(dest_buf, KM_USER0);
+ kunmap_atomic(src_buf, KM_USER1);
async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param);
}
diff -puN drivers/md/raid5.c~async_tx-fix-kmap_atomic-usage-in-async_memcpy drivers/md/raid5.c
--- a/drivers/md/raid5.c~async_tx-fix-kmap_atomic-usage-in-async_memcpy
+++ a/drivers/md/raid5.c
@@ -493,12 +493,12 @@ async_copy_data(int frombio, struct bio
if (frombio)
tx = async_memcpy(page, bio_page, page_offset,
b_offset, clen,
- ASYNC_TX_DEP_ACK | ASYNC_TX_KMAP_SRC,
+ ASYNC_TX_DEP_ACK,
tx, NULL, NULL);
else
tx = async_memcpy(bio_page, page, b_offset,
page_offset, clen,
- ASYNC_TX_DEP_ACK | ASYNC_TX_KMAP_DST,
+ ASYNC_TX_DEP_ACK,
tx, NULL, NULL);
}
if (clen < len) /* hit end of page */
diff -puN include/linux/async_tx.h~async_tx-fix-kmap_atomic-usage-in-async_memcpy include/linux/async_tx.h
--- a/include/linux/async_tx.h~async_tx-fix-kmap_atomic-usage-in-async_memcpy
+++ a/include/linux/async_tx.h
@@ -51,10 +51,6 @@ struct dma_chan_ref {
* @ASYNC_TX_ACK: immediately ack the descriptor, precludes setting up a
* dependency chain
* @ASYNC_TX_DEP_ACK: ack the dependency descriptor. Useful for chaining.
- * @ASYNC_TX_KMAP_SRC: if the transaction is to be performed synchronously
- * take an atomic mapping (KM_USER0) on the source page(s)
- * @ASYNC_TX_KMAP_DST: if the transaction is to be performed synchronously
- * take an atomic mapping (KM_USER0) on the dest page(s)
*/
enum async_tx_flags {
ASYNC_TX_XOR_ZERO_DST = (1 << 0),
@@ -62,8 +58,6 @@ enum async_tx_flags {
ASYNC_TX_ASSUME_COHERENT = (1 << 2),
ASYNC_TX_ACK = (1 << 3),
ASYNC_TX_DEP_ACK = (1 << 4),
- ASYNC_TX_KMAP_SRC = (1 << 5),
- ASYNC_TX_KMAP_DST = (1 << 6),
};
#ifdef CONFIG_DMA_ENGINE
_
Patches currently in -mm which might be from dan.j.williams@xxxxxxxxx are
origin.patch
async_tx-fix-kmap_atomic-usage-in-async_memcpy.patch
raid5-add-the-stripe_queue-object-for-tracking-raid.patch
raid5-add-the-stripe_queue-object-for-tracking-raid-io-requests-take2.patch
raid5-use-stripe_queues-to-prioritize-the-most.patch
-
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