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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /drivers/scsi/sd_dif.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'drivers/scsi/sd_dif.c')
-rw-r--r-- | drivers/scsi/sd_dif.c | 481 |
1 files changed, 481 insertions, 0 deletions
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c new file mode 100644 index 00000000..e52d5bc4 --- /dev/null +++ b/drivers/scsi/sd_dif.c @@ -0,0 +1,481 @@ +/* + * sd_dif.c - SCSI Data Integrity Field + * + * Copyright (C) 2007, 2008 Oracle Corporation + * Written by: Martin K. Petersen <martin.petersen@oracle.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; see the file COPYING. If not, write to + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, + * USA. + * + */ + +#include <linux/blkdev.h> +#include <linux/crc-t10dif.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_dbg.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_driver.h> +#include <scsi/scsi_eh.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_ioctl.h> +#include <scsi/scsicam.h> + +#include <net/checksum.h> + +#include "sd.h" + +typedef __u16 (csum_fn) (void *, unsigned int); + +static __u16 sd_dif_crc_fn(void *data, unsigned int len) +{ + return cpu_to_be16(crc_t10dif(data, len)); +} + +static __u16 sd_dif_ip_fn(void *data, unsigned int len) +{ + return ip_compute_csum(data, len); +} + +/* + * Type 1 and Type 2 protection use the same format: 16 bit guard tag, + * 16 bit app tag, 32 bit reference tag. + */ +static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn) +{ + void *buf = bix->data_buf; + struct sd_dif_tuple *sdt = bix->prot_buf; + sector_t sector = bix->sector; + unsigned int i; + + for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) { + sdt->guard_tag = fn(buf, bix->sector_size); + sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); + sdt->app_tag = 0; + + buf += bix->sector_size; + sector++; + } +} + +static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix) +{ + sd_dif_type1_generate(bix, sd_dif_crc_fn); +} + +static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix) +{ + sd_dif_type1_generate(bix, sd_dif_ip_fn); +} + +static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn) +{ + void *buf = bix->data_buf; + struct sd_dif_tuple *sdt = bix->prot_buf; + sector_t sector = bix->sector; + unsigned int i; + __u16 csum; + + for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) { + /* Unwritten sectors */ + if (sdt->app_tag == 0xffff) + return 0; + + /* Bad ref tag received from disk */ + if (sdt->ref_tag == 0xffffffff) { + printk(KERN_ERR + "%s: bad phys ref tag on sector %lu\n", + bix->disk_name, (unsigned long)sector); + return -EIO; + } + + if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) { + printk(KERN_ERR + "%s: ref tag error on sector %lu (rcvd %u)\n", + bix->disk_name, (unsigned long)sector, + be32_to_cpu(sdt->ref_tag)); + return -EIO; + } + + csum = fn(buf, bix->sector_size); + + if (sdt->guard_tag != csum) { + printk(KERN_ERR "%s: guard tag error on sector %lu " \ + "(rcvd %04x, data %04x)\n", bix->disk_name, + (unsigned long)sector, + be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); + return -EIO; + } + + buf += bix->sector_size; + sector++; + } + + return 0; +} + +static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix) +{ + return sd_dif_type1_verify(bix, sd_dif_crc_fn); +} + +static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix) +{ + return sd_dif_type1_verify(bix, sd_dif_ip_fn); +} + +/* + * Functions for interleaving and deinterleaving application tags + */ +static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors) +{ + struct sd_dif_tuple *sdt = prot; + u8 *tag = tag_buf; + unsigned int i, j; + + for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) { + sdt->app_tag = tag[j] << 8 | tag[j+1]; + BUG_ON(sdt->app_tag == 0xffff); + } +} + +static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors) +{ + struct sd_dif_tuple *sdt = prot; + u8 *tag = tag_buf; + unsigned int i, j; + + for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) { + tag[j] = (sdt->app_tag & 0xff00) >> 8; + tag[j+1] = sdt->app_tag & 0xff; + } +} + +static struct blk_integrity dif_type1_integrity_crc = { + .name = "T10-DIF-TYPE1-CRC", + .generate_fn = sd_dif_type1_generate_crc, + .verify_fn = sd_dif_type1_verify_crc, + .get_tag_fn = sd_dif_type1_get_tag, + .set_tag_fn = sd_dif_type1_set_tag, + .tuple_size = sizeof(struct sd_dif_tuple), + .tag_size = 0, +}; + +static struct blk_integrity dif_type1_integrity_ip = { + .name = "T10-DIF-TYPE1-IP", + .generate_fn = sd_dif_type1_generate_ip, + .verify_fn = sd_dif_type1_verify_ip, + .get_tag_fn = sd_dif_type1_get_tag, + .set_tag_fn = sd_dif_type1_set_tag, + .tuple_size = sizeof(struct sd_dif_tuple), + .tag_size = 0, +}; + + +/* + * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque + * tag space. + */ +static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn) +{ + void *buf = bix->data_buf; + struct sd_dif_tuple *sdt = bix->prot_buf; + unsigned int i; + + for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) { + sdt->guard_tag = fn(buf, bix->sector_size); + sdt->ref_tag = 0; + sdt->app_tag = 0; + + buf += bix->sector_size; + } +} + +static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix) +{ + sd_dif_type3_generate(bix, sd_dif_crc_fn); +} + +static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix) +{ + sd_dif_type3_generate(bix, sd_dif_ip_fn); +} + +static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn) +{ + void *buf = bix->data_buf; + struct sd_dif_tuple *sdt = bix->prot_buf; + sector_t sector = bix->sector; + unsigned int i; + __u16 csum; + + for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) { + /* Unwritten sectors */ + if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff) + return 0; + + csum = fn(buf, bix->sector_size); + + if (sdt->guard_tag != csum) { + printk(KERN_ERR "%s: guard tag error on sector %lu " \ + "(rcvd %04x, data %04x)\n", bix->disk_name, + (unsigned long)sector, + be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum)); + return -EIO; + } + + buf += bix->sector_size; + sector++; + } + + return 0; +} + +static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix) +{ + return sd_dif_type3_verify(bix, sd_dif_crc_fn); +} + +static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix) +{ + return sd_dif_type3_verify(bix, sd_dif_ip_fn); +} + +static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors) +{ + struct sd_dif_tuple *sdt = prot; + u8 *tag = tag_buf; + unsigned int i, j; + + for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) { + sdt->app_tag = tag[j] << 8 | tag[j+1]; + sdt->ref_tag = tag[j+2] << 24 | tag[j+3] << 16 | + tag[j+4] << 8 | tag[j+5]; + } +} + +static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors) +{ + struct sd_dif_tuple *sdt = prot; + u8 *tag = tag_buf; + unsigned int i, j; + + for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) { + tag[j] = (sdt->app_tag & 0xff00) >> 8; + tag[j+1] = sdt->app_tag & 0xff; + tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24; + tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16; + tag[j+4] = (sdt->ref_tag & 0xff00) >> 8; + tag[j+5] = sdt->ref_tag & 0xff; + BUG_ON(sdt->app_tag == 0xffff || sdt->ref_tag == 0xffffffff); + } +} + +static struct blk_integrity dif_type3_integrity_crc = { + .name = "T10-DIF-TYPE3-CRC", + .generate_fn = sd_dif_type3_generate_crc, + .verify_fn = sd_dif_type3_verify_crc, + .get_tag_fn = sd_dif_type3_get_tag, + .set_tag_fn = sd_dif_type3_set_tag, + .tuple_size = sizeof(struct sd_dif_tuple), + .tag_size = 0, +}; + +static struct blk_integrity dif_type3_integrity_ip = { + .name = "T10-DIF-TYPE3-IP", + .generate_fn = sd_dif_type3_generate_ip, + .verify_fn = sd_dif_type3_verify_ip, + .get_tag_fn = sd_dif_type3_get_tag, + .set_tag_fn = sd_dif_type3_set_tag, + .tuple_size = sizeof(struct sd_dif_tuple), + .tag_size = 0, +}; + +/* + * Configure exchange of protection information between OS and HBA. + */ +void sd_dif_config_host(struct scsi_disk *sdkp) +{ + struct scsi_device *sdp = sdkp->device; + struct gendisk *disk = sdkp->disk; + u8 type = sdkp->protection_type; + int dif, dix; + + dif = scsi_host_dif_capable(sdp->host, type); + dix = scsi_host_dix_capable(sdp->host, type); + + if (!dix && scsi_host_dix_capable(sdp->host, 0)) { + dif = 0; dix = 1; + } + + if (!dix) + return; + + /* Enable DMA of protection information */ + if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) + if (type == SD_DIF_TYPE3_PROTECTION) + blk_integrity_register(disk, &dif_type3_integrity_ip); + else + blk_integrity_register(disk, &dif_type1_integrity_ip); + else + if (type == SD_DIF_TYPE3_PROTECTION) + blk_integrity_register(disk, &dif_type3_integrity_crc); + else + blk_integrity_register(disk, &dif_type1_integrity_crc); + + sd_printk(KERN_NOTICE, sdkp, + "Enabling DIX %s protection\n", disk->integrity->name); + + /* Signal to block layer that we support sector tagging */ + if (dif && type && sdkp->ATO) { + if (type == SD_DIF_TYPE3_PROTECTION) + disk->integrity->tag_size = sizeof(u16) + sizeof(u32); + else + disk->integrity->tag_size = sizeof(u16); + + sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n", + disk->integrity->tag_size); + } +} + +/* + * 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. + */ +int sd_dif_prepare(struct request *rq, sector_t hw_sector, unsigned int sector_sz) +{ + const int tuple_sz = sizeof(struct sd_dif_tuple); + struct bio *bio; + struct scsi_disk *sdkp; + struct sd_dif_tuple *sdt; + unsigned int i, j; + u32 phys, virt; + + sdkp = rq->bio->bi_bdev->bd_disk->private_data; + + if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION) + return 0; + + phys = hw_sector & 0xffffffff; + + __rq_for_each_bio(bio, rq) { + struct bio_vec *iv; + + /* Already remapped? */ + if (bio_flagged(bio, BIO_MAPPED_INTEGRITY)) + break; + + virt = bio->bi_integrity->bip_sector & 0xffffffff; + + bip_for_each_vec(iv, bio->bi_integrity, i) { + sdt = kmap_atomic(iv->bv_page) + + iv->bv_offset; + + for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) { + + if (be32_to_cpu(sdt->ref_tag) != virt) + goto error; + + sdt->ref_tag = cpu_to_be32(phys); + virt++; + phys++; + } + + kunmap_atomic(sdt); + } + + bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY); + } + + return 0; + +error: + kunmap_atomic(sdt); + sd_printk(KERN_ERR, sdkp, "%s: virt %u, phys %u, ref %u, app %4x\n", + __func__, virt, phys, be32_to_cpu(sdt->ref_tag), + be16_to_cpu(sdt->app_tag)); + + return -EILSEQ; +} + +/* + * 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 sd_dif_tuple); + struct scsi_disk *sdkp; + struct bio *bio; + struct sd_dif_tuple *sdt; + unsigned int i, j, sectors, sector_sz; + u32 phys, virt; + + sdkp = scsi_disk(scmd->request->rq_disk); + + if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0) + return; + + sector_sz = scmd->device->sector_size; + sectors = good_bytes / sector_sz; + + phys = blk_rq_pos(scmd->request) & 0xffffffff; + if (sector_sz == 4096) + phys >>= 3; + + __rq_for_each_bio(bio, scmd->request) { + struct bio_vec *iv; + + virt = bio->bi_integrity->bip_sector & 0xffffffff; + + bip_for_each_vec(iv, bio->bi_integrity, i) { + sdt = kmap_atomic(iv->bv_page) + + iv->bv_offset; + + for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) { + + if (sectors == 0) { + kunmap_atomic(sdt); + return; + } + + if (be32_to_cpu(sdt->ref_tag) != phys && + sdt->app_tag != 0xffff) + sdt->ref_tag = 0xffffffff; /* Bad ref */ + else + sdt->ref_tag = cpu_to_be32(virt); + + virt++; + phys++; + sectors--; + } + + kunmap_atomic(sdt); + } + } +} + |