Currently these functions are implemented in the scsi layer, but their actual place should be the block layer since T10-PI is a general data integrity feature that is used in the nvme protocol as well.
Suggested-by: Christoph Hellwig <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Martin K. Petersen <[email protected]> Signed-off-by: Max Gurtovoy <[email protected]> --- block/blk-integrity.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/scsi/sd.c | 12 ++++-- drivers/scsi/sd.h | 9 ---- drivers/scsi/sd_dif.c | 113 ------------------------------------------------- include/linux/blkdev.h | 14 ++++++ 5 files changed, 134 insertions(+), 125 deletions(-) diff --git a/block/blk-integrity.c b/block/blk-integrity.c index 6121611e1316..66b095a866d3 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -21,6 +21,7 @@ */ #include <linux/blkdev.h> +#include <linux/t10-pi.h> #include <linux/backing-dev.h> #include <linux/mempool.h> #include <linux/bio.h> @@ -451,3 +452,113 @@ void blk_integrity_del(struct gendisk *disk) kobject_del(&disk->integrity_kobj); kobject_put(&disk->integrity_kobj); } + +/* + * The virtual start sector is the one that was originally submitted + * by the block layer. Due to partitioning, MD/DM cloning, etc. the + * actual physical start sector is likely to be different. Remap + * protection information to match the physical LBA. + * + * From a protocol perspective there's a slight difference between + * Type 1 and 2. The latter uses command's 32-byte exclusively, and the + * reference tag is seeded in the command. This gives us the potential to + * avoid virt->phys remapping during write. However, at read time we + * don't know whether the virt sector is the same as when we wrote it + * (we could be reading from real disk as opposed to MD/DM device. So + * we always remap Type 2 making it identical to Type 1. + * + * Type 3 does not have a reference tag so no remapping is required. + */ +void blk_integrity_dif_prepare(struct request *rq, u8 protection_type, + u32 ref_tag) +{ + const int tuple_sz = sizeof(struct t10_pi_tuple); + struct bio *bio; + struct t10_pi_tuple *pi; + u32 phys, virt; + + if (protection_type == T10_PI_TYPE3_PROTECTION) + return; + + phys = ref_tag; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + struct bio_vec iv; + struct bvec_iter iter; + unsigned int j; + + /* Already remapped? */ + if (bip->bip_flags & BIP_MAPPED_INTEGRITY) + break; + + virt = bip_get_seed(bip) & 0xffffffff; + + bip_for_each_vec(iv, bip, iter) { + pi = kmap_atomic(iv.bv_page) + iv.bv_offset; + + for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) { + + if (be32_to_cpu(pi->ref_tag) == virt) + pi->ref_tag = cpu_to_be32(phys); + + virt++; + phys++; + } + + kunmap_atomic(pi); + } + + bip->bip_flags |= BIP_MAPPED_INTEGRITY; + } +} +EXPORT_SYMBOL(blk_integrity_dif_prepare); + +/* + * Remap physical sector values in the reference tag to the virtual + * values expected by the block layer. + */ +void blk_integrity_dif_complete(struct request *rq, u8 protection_type, + u32 ref_tag, unsigned int intervals) +{ + const int tuple_sz = sizeof(struct t10_pi_tuple); + struct bio *bio; + struct t10_pi_tuple *pi; + unsigned int j; + u32 phys, virt; + + if (protection_type == T10_PI_TYPE3_PROTECTION) + return; + + phys = ref_tag; + + __rq_for_each_bio(bio, rq) { + struct bio_integrity_payload *bip = bio_integrity(bio); + struct bio_vec iv; + struct bvec_iter iter; + + virt = bip_get_seed(bip) & 0xffffffff; + + bip_for_each_vec(iv, bip, iter) { + pi = kmap_atomic(iv.bv_page) + iv.bv_offset; + + for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) { + + if (intervals == 0) { + kunmap_atomic(pi); + return; + } + + if (be32_to_cpu(pi->ref_tag) == phys) + pi->ref_tag = cpu_to_be32(virt); + + virt++; + phys++; + intervals--; + } + + kunmap_atomic(pi); + } + } +} +EXPORT_SYMBOL(blk_integrity_dif_complete); diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 9421d9877730..4186bf027c59 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1119,7 +1119,9 @@ static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt) SCpnt->cmnd[0] = WRITE_6; if (blk_integrity_rq(rq)) - sd_dif_prepare(SCpnt); + blk_integrity_dif_prepare(SCpnt->request, + sdkp->protection_type, + scsi_prot_ref_tag(SCpnt)); } else if (rq_data_dir(rq) == READ) { SCpnt->cmnd[0] = READ_6; @@ -2047,8 +2049,12 @@ static int sd_done(struct scsi_cmnd *SCpnt) "sd_done: completed %d of %d bytes\n", good_bytes, scsi_bufflen(SCpnt))); - if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt)) - sd_dif_complete(SCpnt, good_bytes); + if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt) && + good_bytes) + blk_integrity_dif_complete(SCpnt->request, + sdkp->protection_type, + scsi_prot_ref_tag(SCpnt), + good_bytes / scsi_prot_interval(SCpnt)); return good_bytes; } diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h index 392c7d078ae3..a7d4f50b67d4 100644 --- a/drivers/scsi/sd.h +++ b/drivers/scsi/sd.h @@ -254,21 +254,12 @@ static inline unsigned int sd_prot_flag_mask(unsigned int prot_op) #ifdef CONFIG_BLK_DEV_INTEGRITY extern void sd_dif_config_host(struct scsi_disk *); -extern void sd_dif_prepare(struct scsi_cmnd *scmd); -extern void sd_dif_complete(struct scsi_cmnd *, unsigned int); #else /* CONFIG_BLK_DEV_INTEGRITY */ static inline void sd_dif_config_host(struct scsi_disk *disk) { } -static inline int sd_dif_prepare(struct scsi_cmnd *scmd) -{ - return 0; -} -static inline void sd_dif_complete(struct scsi_cmnd *cmd, unsigned int a) -{ -} #endif /* CONFIG_BLK_DEV_INTEGRITY */ diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c index 9035380c0dda..db72c82486e3 100644 --- a/drivers/scsi/sd_dif.c +++ b/drivers/scsi/sd_dif.c @@ -95,116 +95,3 @@ void sd_dif_config_host(struct scsi_disk *sdkp) blk_integrity_register(disk, &bi); } -/* - * The virtual start sector is the one that was originally submitted - * by the block layer. Due to partitioning, MD/DM cloning, etc. the - * actual physical start sector is likely to be different. Remap - * protection information to match the physical LBA. - * - * From a protocol perspective there's a slight difference between - * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the - * reference tag is seeded in the CDB. This gives us the potential to - * avoid virt->phys remapping during write. However, at read time we - * don't know whether the virt sector is the same as when we wrote it - * (we could be reading from real disk as opposed to MD/DM device. So - * we always remap Type 2 making it identical to Type 1. - * - * Type 3 does not have a reference tag so no remapping is required. - */ -void sd_dif_prepare(struct scsi_cmnd *scmd) -{ - const int tuple_sz = sizeof(struct t10_pi_tuple); - struct bio *bio; - struct scsi_disk *sdkp; - struct t10_pi_tuple *pi; - u32 phys, virt; - - sdkp = scsi_disk(scmd->request->rq_disk); - - if (sdkp->protection_type == T10_PI_TYPE3_PROTECTION) - return; - - phys = scsi_prot_ref_tag(scmd); - - __rq_for_each_bio(bio, scmd->request) { - struct bio_integrity_payload *bip = bio_integrity(bio); - struct bio_vec iv; - struct bvec_iter iter; - unsigned int j; - - /* Already remapped? */ - if (bip->bip_flags & BIP_MAPPED_INTEGRITY) - break; - - virt = bip_get_seed(bip) & 0xffffffff; - - bip_for_each_vec(iv, bip, iter) { - pi = kmap_atomic(iv.bv_page) + iv.bv_offset; - - for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) { - - if (be32_to_cpu(pi->ref_tag) == virt) - pi->ref_tag = cpu_to_be32(phys); - - virt++; - phys++; - } - - kunmap_atomic(pi); - } - - bip->bip_flags |= BIP_MAPPED_INTEGRITY; - } -} - -/* - * Remap physical sector values in the reference tag to the virtual - * values expected by the block layer. - */ -void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes) -{ - const int tuple_sz = sizeof(struct t10_pi_tuple); - struct scsi_disk *sdkp; - struct bio *bio; - struct t10_pi_tuple *pi; - unsigned int j, intervals; - u32 phys, virt; - - sdkp = scsi_disk(scmd->request->rq_disk); - - if (sdkp->protection_type == T10_PI_TYPE3_PROTECTION || good_bytes == 0) - return; - - intervals = good_bytes / scsi_prot_interval(scmd); - phys = scsi_prot_ref_tag(scmd); - - __rq_for_each_bio(bio, scmd->request) { - struct bio_integrity_payload *bip = bio_integrity(bio); - struct bio_vec iv; - struct bvec_iter iter; - - virt = bip_get_seed(bip) & 0xffffffff; - - bip_for_each_vec(iv, bip, iter) { - pi = kmap_atomic(iv.bv_page) + iv.bv_offset; - - for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) { - - if (intervals == 0) { - kunmap_atomic(pi); - return; - } - - if (be32_to_cpu(pi->ref_tag) == phys) - pi->ref_tag = cpu_to_be32(virt); - - virt++; - phys++; - intervals--; - } - - kunmap_atomic(pi); - } - } -} - diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 79226ca8f80f..18f3ca17d4f4 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1823,6 +1823,10 @@ extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, struct request *); extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, struct bio *); +extern void blk_integrity_dif_prepare(struct request *rq, u8 protection_type, + u32 ref_tag); +extern void blk_integrity_dif_complete(struct request *rq, u8 protection_type, + u32 ref_tag, unsigned int intervals); static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) { @@ -1950,6 +1954,16 @@ static inline bool integrity_req_gap_front_merge(struct request *req, return false; } +void blk_integrity_dif_prepare(struct request *rq, u8 protection_type, + u32 ref_tag) +{ +} + +void blk_integrity_dif_complete(struct request *rq, u8 protection_type, + u32 ref_tag, unsigned int intervals) +{ +} + #endif /* CONFIG_BLK_DEV_INTEGRITY */ struct block_device_operations { -- 2.16.3
