Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760185AbYFGE7x (ORCPT ); Sat, 7 Jun 2008 00:59:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755660AbYFGE6a (ORCPT ); Sat, 7 Jun 2008 00:58:30 -0400 Received: from jaguar.mkp.net ([192.139.46.146]:38421 "EHLO jaguar.mkp.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751882AbYFGE5o (ORCPT ); Sat, 7 Jun 2008 00:57:44 -0400 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [PATCH 6 of 7] scsi: Support devices with protection information (DIF) X-Mercurial-Node: ad65bfde4e05e43072b60768802c8bbe5e759538 Message-Id: In-Reply-To: Date: Sat, 07 Jun 2008 00:55:39 -0400 From: "Martin K. Petersen" To: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5363 Lines: 183 5 files changed, 90 insertions(+) drivers/scsi/Kconfig | 15 +++++++++++++++ drivers/scsi/scsi_lib.c | 42 ++++++++++++++++++++++++++++++++++++++++++ drivers/scsi/scsi_scan.c | 3 +++ include/scsi/scsi_cmnd.h | 29 +++++++++++++++++++++++++++++ include/scsi/scsi_device.h | 1 + - Add support for an extra scatter-gather list containing protection information. - Remember devices with protection information turned on in INQUIRY. Signed-off-by: Martin K. Petersen --- diff -r 5be7c534c954 -r ad65bfde4e05 drivers/scsi/Kconfig --- a/drivers/scsi/Kconfig Sat Jun 07 00:45:15 2008 -0400 +++ b/drivers/scsi/Kconfig Sat Jun 07 00:45:15 2008 -0400 @@ -260,6 +260,21 @@ default m depends on SCSI depends on MODULES + +config SCSI_PROTECTION + bool "SCSI Data Integrity Protection" + depends on SCSI + depends on BLK_DEV_INTEGRITY + help + Some SCSI devices support data protection features above and + beyond those implemented in the transport. Select this + option to enable protection information to be transferred to + and from a device. Specifically, this option will enable DIF + (Data Integrity Field) for SCSI disks. + + The SCSI protection features depend on the block layer data + integrity infrastructure so the latter must be enabled for + this option to work. menu "SCSI Transports" depends on SCSI diff -r 5be7c534c954 -r ad65bfde4e05 drivers/scsi/scsi_lib.c --- a/drivers/scsi/scsi_lib.c Sat Jun 07 00:45:15 2008 -0400 +++ b/drivers/scsi/scsi_lib.c Sat Jun 07 00:45:15 2008 -0400 @@ -778,6 +778,13 @@ kmem_cache_free(scsi_sdb_cache, bidi_sdb); cmd->request->next_rq->special = NULL; } + +#if defined(CONFIG_SCSI_PROTECTION) + if (scsi_prot_sg_count(cmd)) { + scsi_free_sgtable(cmd->prot_sdb); + kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb); + } +#endif } EXPORT_SYMBOL(scsi_release_buffers); @@ -1031,6 +1038,32 @@ return BLKPREP_OK; } +#if defined(CONFIG_SCSI_PROTECTION) +static int scsi_protect_io(struct scsi_cmnd *cmd, gfp_t gfp_mask) +{ + struct request *req = cmd->request; + struct scsi_data_buffer *pdb; + int ivecs, count; + + pdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask); + if (unlikely(pdb == NULL)) + return BLKPREP_DEFER; + + ivecs = blk_rq_count_integrity_sg(req); + + if (unlikely(scsi_alloc_sgtable(pdb, ivecs, gfp_mask))) + return BLKPREP_DEFER; + + count = blk_rq_map_integrity_sg(req, pdb->table.sgl); + BUG_ON(unlikely(count > ivecs)); + + cmd->prot_sdb = pdb; + cmd->prot_sdb->table.nents = count; + + return BLKPREP_OK; +} +#endif + /* * Function: scsi_init_io() * @@ -1062,6 +1095,15 @@ if (error) goto err_exit; } + +#if defined(CONFIG_SCSI_PROTECTION) + if (blk_integrity_rq(cmd->request)) { + error = scsi_protect_io(cmd, gfp_mask); + + if (error != BLKPREP_OK) + goto err_exit; + } +#endif return BLKPREP_OK ; diff -r 5be7c534c954 -r ad65bfde4e05 drivers/scsi/scsi_scan.c --- a/drivers/scsi/scsi_scan.c Sat Jun 07 00:45:15 2008 -0400 +++ b/drivers/scsi/scsi_scan.c Sat Jun 07 00:45:15 2008 -0400 @@ -882,6 +882,9 @@ if (*bflags & BLIST_USE_10_BYTE_MS) sdev->use_10_for_ms = 1; + + if (inq_result[5] & 0x1) + sdev->protection = 1; /* set the device running here so that slave configure * may do I/O */ diff -r 5be7c534c954 -r ad65bfde4e05 include/scsi/scsi_cmnd.h --- a/include/scsi/scsi_cmnd.h Sat Jun 07 00:45:15 2008 -0400 +++ b/include/scsi/scsi_cmnd.h Sat Jun 07 00:45:15 2008 -0400 @@ -88,6 +88,9 @@ /* These elements define the operation we ultimately want to perform */ struct scsi_data_buffer sdb; +#if defined(CONFIG_SCSI_PROTECTION) + struct scsi_data_buffer *prot_sdb; +#endif unsigned underflow; /* Return error if less than this amount is transferred */ @@ -209,4 +212,30 @@ buf, buflen); } +#if defined(CONFIG_SCSI_PROTECTION) + +static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd) +{ + return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0; +} + +static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd) +{ + return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL; +} + +static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd) +{ + return cmd->prot_sdb; +} + +#define scsi_for_each_prot_sg(cmd, sg, nseg, __i) \ + for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i) + +#else /* CONFIG_SCSI_PROTECTION */ + +#define scsi_prot_sg_count(a) (0) + +#endif /* CONFIG_SCSI_PROTECTION */ + #endif /* _SCSI_SCSI_CMND_H */ diff -r 5be7c534c954 -r ad65bfde4e05 include/scsi/scsi_device.h --- a/include/scsi/scsi_device.h Sat Jun 07 00:45:15 2008 -0400 +++ b/include/scsi/scsi_device.h Sat Jun 07 00:45:15 2008 -0400 @@ -140,6 +140,7 @@ unsigned guess_capacity:1; /* READ_CAPACITY might be too high by 1 */ unsigned retry_hwerror:1; /* Retry HARDWARE_ERROR */ unsigned last_sector_bug:1; /* Always read last sector in a 1 sector read */ + unsigned protection:1; /* Data Integrity Field */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/