This is a note to let you know that I've just added the patch titled

crypto: crypto4xx - increase context and scatter ring buffer elements

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: crypto-crypto4xx-increase-context-and-scatter-ring-buffer-elements.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Wed Dec 20 18:17:52 CET 2017

From: Christian Lamparter chunkeey@gmail.com Date: Wed, 4 Oct 2017 01:00:08 +0200 Subject: crypto: crypto4xx - increase context and scatter ring buffer elements

From: Christian Lamparter chunkeey@gmail.com

[ Upstream commit 778f81d6cdb7d25360f082ac0384d5103f04eca5 ]

If crypto4xx is used in conjunction with dm-crypt, the available ring buffer elements are not enough to handle the load properly.

On an aes-cbc-essiv:sha256 encrypted swap partition the read performance is abyssal: (tested with hdparm -t)

/dev/mapper/swap_crypt: Timing buffered disk reads: 14 MB in 3.68 seconds = 3.81 MB/sec

The patch increases both PPC4XX_NUM_SD and PPC4XX_NUM_PD to 256. This improves the performance considerably:

/dev/mapper/swap_crypt: Timing buffered disk reads: 104 MB in 3.03 seconds = 34.31 MB/sec

Furthermore, PPC4XX_LAST_SD, PPC4XX_LAST_GD and PPC4XX_LAST_PD can be easily calculated from their respective PPC4XX_NUM_* constant.

Signed-off-by: Christian Lamparter chunkeey@gmail.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/crypto/amcc/crypto4xx_core.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/crypto/amcc/crypto4xx_core.h +++ b/drivers/crypto/amcc/crypto4xx_core.h @@ -34,12 +34,12 @@ #define PPC405EX_CE_RESET 0x00000008

#define CRYPTO4XX_CRYPTO_PRIORITY 300 -#define PPC4XX_LAST_PD 63 -#define PPC4XX_NUM_PD 64 -#define PPC4XX_LAST_GD 1023 +#define PPC4XX_NUM_PD 256 +#define PPC4XX_LAST_PD (PPC4XX_NUM_PD - 1) #define PPC4XX_NUM_GD 1024 -#define PPC4XX_LAST_SD 63 -#define PPC4XX_NUM_SD 64 +#define PPC4XX_LAST_GD (PPC4XX_NUM_GD - 1) +#define PPC4XX_NUM_SD 256 +#define PPC4XX_LAST_SD (PPC4XX_NUM_SD - 1) #define PPC4XX_SD_BUFFER_SIZE 2048

#define PD_ENTRY_INUSE 1

Patches currently in stable-queue which might be from chunkeey@gmail.com are

queue-4.14/crypto-crypto4xx-increase-context-and-scatter-ring-buffer-elements.patch