From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anup Patel Subject: [PATCH v3 1/4] lib/raid6: Add log-of-2 table for RAID6 HW requiring disk position Date: Fri, 10 Feb 2017 14:37:05 +0530 Message-ID: <1486717628-17580-2-git-send-email-anup.patel@broadcom.com> References: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: devicetree@vger.kernel.org, Anup Patel , Scott Branden , Jon Mason , Ray Jui , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, linux-crypto@vger.kernel.org, Rob Rice , dmaengine@vger.kernel.org, Dan Williams , linux-arm-kernel@lists.infradead.org To: Vinod Koul , Rob Herring , Mark Rutland , Herbert Xu , "David S . Miller" , Jassi Brar Return-path: In-Reply-To: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-crypto.vger.kernel.org The raid6_gfexp table represents {2}^n values for 0 <= n < 256. The Linux async_tx framework pass values from raid6_gfexp as coefficients for each source to prep_dma_pq() callback of DMA channel with PQ capability. This creates problem for RAID6 offload engines (such as Broadcom SBA) which take disk position (i.e. log of {2}) instead of multiplicative cofficients from raid6_gfexp table. This patch adds raid6_gflog table having log-of-2 value for any given x such that 0 <= x < 256. For any given disk coefficient x, the corresponding disk position is given by raid6_gflog[x]. The RAID6 offload engine driver can use this newly added raid6_gflog table to get disk position from multiplicative coefficient. Signed-off-by: Anup Patel Reviewed-by: Scott Branden Reviewed-by: Ray Jui --- include/linux/raid/pq.h | 1 + lib/raid6/mktables.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/include/linux/raid/pq.h b/include/linux/raid/pq.h index 4d57bba..30f9453 100644 --- a/include/linux/raid/pq.h +++ b/include/linux/raid/pq.h @@ -142,6 +142,7 @@ int raid6_select_algo(void); extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256))); extern const u8 raid6_gfexp[256] __attribute__((aligned(256))); +extern const u8 raid6_gflog[256] __attribute__((aligned(256))); extern const u8 raid6_gfinv[256] __attribute__((aligned(256))); extern const u8 raid6_gfexi[256] __attribute__((aligned(256))); diff --git a/lib/raid6/mktables.c b/lib/raid6/mktables.c index 39787db..e824d08 100644 --- a/lib/raid6/mktables.c +++ b/lib/raid6/mktables.c @@ -125,6 +125,26 @@ int main(int argc, char *argv[]) printf("EXPORT_SYMBOL(raid6_gfexp);\n"); printf("#endif\n"); + /* Compute log-of-2 table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gflog[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + v = 255; + for (k = 0; k < 256; k++) + if (exptbl[k] == (i + j)) { + v = k; + break; + } + printf("0x%02x,%c", v, (j == 7) ? '\n' : ' '); + } + } + printf("};\n"); + printf("#ifdef __KERNEL__\n"); + printf("EXPORT_SYMBOL(raid6_gflog);\n"); + printf("#endif\n"); + /* Compute inverse table x^-1 == x^254 */ printf("\nconst u8 __attribute__((aligned(256)))\n" "raid6_gfinv[256] =\n" "{\n"); -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752504AbdBJJJm (ORCPT ); Fri, 10 Feb 2017 04:09:42 -0500 Received: from mail-wr0-f177.google.com ([209.85.128.177]:35684 "EHLO mail-wr0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751355AbdBJJHw (ORCPT ); Fri, 10 Feb 2017 04:07:52 -0500 From: Anup Patel To: Vinod Koul , Rob Herring , Mark Rutland , Herbert Xu , "David S . Miller" , Jassi Brar Cc: Dan Williams , Ray Jui , Scott Branden , Jon Mason , Rob Rice , bcm-kernel-feedback-list@broadcom.com, dmaengine@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, linux-raid@vger.kernel.org, Anup Patel Subject: [PATCH v3 1/4] lib/raid6: Add log-of-2 table for RAID6 HW requiring disk position Date: Fri, 10 Feb 2017 14:37:05 +0530 Message-Id: <1486717628-17580-2-git-send-email-anup.patel@broadcom.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> References: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The raid6_gfexp table represents {2}^n values for 0 <= n < 256. The Linux async_tx framework pass values from raid6_gfexp as coefficients for each source to prep_dma_pq() callback of DMA channel with PQ capability. This creates problem for RAID6 offload engines (such as Broadcom SBA) which take disk position (i.e. log of {2}) instead of multiplicative cofficients from raid6_gfexp table. This patch adds raid6_gflog table having log-of-2 value for any given x such that 0 <= x < 256. For any given disk coefficient x, the corresponding disk position is given by raid6_gflog[x]. The RAID6 offload engine driver can use this newly added raid6_gflog table to get disk position from multiplicative coefficient. Signed-off-by: Anup Patel Reviewed-by: Scott Branden Reviewed-by: Ray Jui --- include/linux/raid/pq.h | 1 + lib/raid6/mktables.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/include/linux/raid/pq.h b/include/linux/raid/pq.h index 4d57bba..30f9453 100644 --- a/include/linux/raid/pq.h +++ b/include/linux/raid/pq.h @@ -142,6 +142,7 @@ int raid6_select_algo(void); extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256))); extern const u8 raid6_gfexp[256] __attribute__((aligned(256))); +extern const u8 raid6_gflog[256] __attribute__((aligned(256))); extern const u8 raid6_gfinv[256] __attribute__((aligned(256))); extern const u8 raid6_gfexi[256] __attribute__((aligned(256))); diff --git a/lib/raid6/mktables.c b/lib/raid6/mktables.c index 39787db..e824d08 100644 --- a/lib/raid6/mktables.c +++ b/lib/raid6/mktables.c @@ -125,6 +125,26 @@ int main(int argc, char *argv[]) printf("EXPORT_SYMBOL(raid6_gfexp);\n"); printf("#endif\n"); + /* Compute log-of-2 table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gflog[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + v = 255; + for (k = 0; k < 256; k++) + if (exptbl[k] == (i + j)) { + v = k; + break; + } + printf("0x%02x,%c", v, (j == 7) ? '\n' : ' '); + } + } + printf("};\n"); + printf("#ifdef __KERNEL__\n"); + printf("EXPORT_SYMBOL(raid6_gflog);\n"); + printf("#endif\n"); + /* Compute inverse table x^-1 == x^254 */ printf("\nconst u8 __attribute__((aligned(256)))\n" "raid6_gfinv[256] =\n" "{\n"); -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: anup.patel@broadcom.com (Anup Patel) Date: Fri, 10 Feb 2017 14:37:05 +0530 Subject: [PATCH v3 1/4] lib/raid6: Add log-of-2 table for RAID6 HW requiring disk position In-Reply-To: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> References: <1486717628-17580-1-git-send-email-anup.patel@broadcom.com> Message-ID: <1486717628-17580-2-git-send-email-anup.patel@broadcom.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The raid6_gfexp table represents {2}^n values for 0 <= n < 256. The Linux async_tx framework pass values from raid6_gfexp as coefficients for each source to prep_dma_pq() callback of DMA channel with PQ capability. This creates problem for RAID6 offload engines (such as Broadcom SBA) which take disk position (i.e. log of {2}) instead of multiplicative cofficients from raid6_gfexp table. This patch adds raid6_gflog table having log-of-2 value for any given x such that 0 <= x < 256. For any given disk coefficient x, the corresponding disk position is given by raid6_gflog[x]. The RAID6 offload engine driver can use this newly added raid6_gflog table to get disk position from multiplicative coefficient. Signed-off-by: Anup Patel Reviewed-by: Scott Branden Reviewed-by: Ray Jui --- include/linux/raid/pq.h | 1 + lib/raid6/mktables.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/include/linux/raid/pq.h b/include/linux/raid/pq.h index 4d57bba..30f9453 100644 --- a/include/linux/raid/pq.h +++ b/include/linux/raid/pq.h @@ -142,6 +142,7 @@ int raid6_select_algo(void); extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256))); extern const u8 raid6_gfexp[256] __attribute__((aligned(256))); +extern const u8 raid6_gflog[256] __attribute__((aligned(256))); extern const u8 raid6_gfinv[256] __attribute__((aligned(256))); extern const u8 raid6_gfexi[256] __attribute__((aligned(256))); diff --git a/lib/raid6/mktables.c b/lib/raid6/mktables.c index 39787db..e824d08 100644 --- a/lib/raid6/mktables.c +++ b/lib/raid6/mktables.c @@ -125,6 +125,26 @@ int main(int argc, char *argv[]) printf("EXPORT_SYMBOL(raid6_gfexp);\n"); printf("#endif\n"); + /* Compute log-of-2 table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gflog[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + v = 255; + for (k = 0; k < 256; k++) + if (exptbl[k] == (i + j)) { + v = k; + break; + } + printf("0x%02x,%c", v, (j == 7) ? '\n' : ' '); + } + } + printf("};\n"); + printf("#ifdef __KERNEL__\n"); + printf("EXPORT_SYMBOL(raid6_gflog);\n"); + printf("#endif\n"); + /* Compute inverse table x^-1 == x^254 */ printf("\nconst u8 __attribute__((aligned(256)))\n" "raid6_gfinv[256] =\n" "{\n"); -- 2.7.4