/* * SCSI Zoned Block commands * * Copyright (C) 2014-2015 SUSE Linux GmbH * Written by: Hannes Reinecke <hare@suse.de> * Modified by: Damien Le Moal <damien.lemoal@hgst.com> * Modified by: Shaun Tancheff <shaun.tancheff@seagate.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 <asm/unaligned.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> #include "sd.h" /** * sd_zbc_parse_report - Convert a zone descriptor to a struct blk_zone, * @sdkp: The disk the report originated from * @buf: Address of the report zone descriptor * @zone: the destination zone structure * * All LBA sized values are converted to 512B sectors unit. */ static void sd_zbc_parse_report(struct scsi_disk *sdkp, u8 *buf, struct blk_zone *zone) { struct scsi_device *sdp = sdkp->device; memset(zone, 0, sizeof(struct blk_zone)); zone->type = buf[0] & 0x0f; zone->cond = (buf[1] >> 4) & 0xf; if (buf[1] & 0x01) zone->reset = 1; if (buf[1] & 0x02) zone->non_seq = 1; zone->len = logical_to_sectors(sdp, get_unaligned_be64(&buf[8])); zone->start = logical_to_sectors(sdp, get_unaligned_be64(&buf[16])); zone->wp = logical_to_sectors(sdp, get_unaligned_be64(&buf[24])); if (zone->type != ZBC_ZONE_TYPE_CONV && zone->cond == ZBC_ZONE_COND_FULL) zone->wp = zone->start + zone->len; } /** * sd_zbc_report_zones - Issue a REPORT ZONES scsi command. * @sdkp: The target disk * @buf: Buffer to use for the reply * @buflen: the buffer size * @lba: Start LBA of the report * * For internal use during device validation. */ static int sd_zbc_report_zones(struct scsi_disk *sdkp, unsigned char *buf, unsigned int buflen, sector_t lba) { struct scsi_device *sdp = sdkp->device; const int timeout = sdp->request_queue->rq_timeout; struct scsi_sense_hdr sshdr; unsigned char cmd[16]; unsigned int rep_len; int result; memset(cmd, 0, 16); cmd[0] = ZBC_IN; cmd[1] = ZI_REPORT_ZONES; put_unaligned_be64(lba, &cmd[2]); put_unaligned_be32(buflen, &cmd[10]); memset(buf, 0, buflen); result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE, buf, buflen, &sshdr, timeout, SD_MAX_RETRIES, NULL); if (result) { sd_printk(KERN_ERR, sdkp, "REPORT ZONES lba %llu failed with %d/%d\n", (unsigned long long)lba, host_byte(result), driver_byte(result)); return -EIO; } rep_len = get_unaligned_be32(&buf[0]); if (rep_len < 64) { sd_printk(KERN_ERR, sdkp, "REPORT ZONES report invalid length %u\n", rep_len); return -EIO; } return 0; } /** * sd_zbc_setup_report_cmnd - Prepare a REPORT ZONES scsi command * @cmd: The command to setup * * Call in sd_init_command() for a REQ_OP_ZONE_REPORT request. */ int sd_zbc_setup_report_cmnd(struct scsi_cmnd *cmd) { struct request *rq = cmd->request; struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); sector_t lba, sector = blk_rq_pos(rq); unsigned int nr_bytes = blk_rq_bytes(rq); int ret; WARN_ON(nr_bytes == 0); if (!sd_is_zoned(sdkp)) /* Not a zoned device */ return BLKPREP_KILL; ret = scsi_init_io(cmd); if (ret != BLKPREP_OK) return ret; cmd->cmd_len = 16; memset(cmd->cmnd, 0, cmd->cmd_len); cmd->cmnd[0] = ZBC_IN; cmd->cmnd[1] = ZI_REPORT_ZONES; lba = sectors_to_logical(sdkp->device, sector); put_unaligned_be64(lba, &cmd->cmnd[2]); put_unaligned_be32(nr_bytes, &cmd->cmnd[10]); /* Do partial report for speeding things up */ cmd->cmnd[14] = ZBC_REPORT_ZONE_PARTIAL; cmd->sc_data_direction = DMA_FROM_DEVICE; cmd->sdb.length = nr_bytes; cmd->transfersize = sdkp->device->sector_size; cmd->allowed = 0; /* * Report may return less bytes than requested. Make sure * to report completion on the entire initial request. */ rq->__data_len = nr_bytes; return BLKPREP_OK; } /** * sd_zbc_report_zones_complete - Process a REPORT ZONES scsi command reply. * @scmd: The completed report zones command * @good_bytes: reply size in bytes * * Convert all reported zone descriptors to struct blk_zone. The conversion * is done in-place, directly in the request specified sg buffer. */ static void sd_zbc_report_zones_complete(struct scsi_cmnd *scmd, unsigned int good_bytes) { struct request *rq = scmd->request; struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); struct sg_mapping_iter miter; struct blk_zone_report_hdr hdr; struct blk_zone zone; unsigned int offset, bytes = 0; unsigned long flags; u8 *buf; if (good_bytes < 64) return; memset(&hdr, 0, sizeof(struct blk_zone_report_hdr)); sg_miter_start(&miter, scsi_sglist(scmd), scsi_sg_count(scmd), SG_MITER_TO_SG | SG_MITER_ATOMIC); local_irq_save(flags); while (sg_miter_next(&miter) && bytes < good_bytes) { buf = miter.addr; offset = 0; if (bytes == 0) { /* Set the report header */ hdr.nr_zones = min_t(unsigned int, (good_bytes - 64) / 64, get_unaligned_be32(&buf[0]) / 64); memcpy(buf, &hdr, sizeof(struct blk_zone_report_hdr)); offset += 64; bytes += 64; } /* Parse zone descriptors */ while (offset < miter.length && hdr.nr_zones) { WARN_ON(offset > miter.length); buf = miter.addr + offset; sd_zbc_parse_report(sdkp, buf, &zone); memcpy(buf, &zone, sizeof(struct blk_zone)); offset += 64; bytes += 64; hdr.nr_zones--; } if (!hdr.nr_zones) break; } sg_miter_stop(&miter); local_irq_restore(flags); } /** * sd_zbc_zone_sectors - Get the device zone size in number of 512B sectors. * @sdkp: The target disk */ static inline sector_t sd_zbc_zone_sectors(struct scsi_disk *sdkp) { return logical_to_sectors(sdkp->device, sdkp->zone_blocks); } /** * sd_zbc_zone_no - Get the number of the zone conataining a sector. * @sdkp: The target disk * @sector: 512B sector address contained in the zone */ static inline unsigned int sd_zbc_zone_no(struct scsi_disk *sdkp, sector_t sector) { return sectors_to_logical(sdkp->device, sector) >> sdkp->zone_shift; } /** * sd_zbc_setup_reset_cmnd - Prepare a RESET WRITE POINTER scsi command. * @cmd: the command to setup * * Called from sd_init_command() for a REQ_OP_ZONE_RESET request. */ int sd_zbc_setup_reset_cmnd(struct scsi_cmnd *cmd) { struct request *rq = cmd->request; struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); sector_t sector = blk_rq_pos(rq); sector_t block = sectors_to_logical(sdkp->device, sector); if (!sd_is_zoned(sdkp)) /* Not a zoned device */ return BLKPREP_KILL; if (sdkp->device->changed) return BLKPREP_KILL; if (sector & (sd_zbc_zone_sectors(sdkp) - 1)) /* Unaligned request */ return BLKPREP_KILL; cmd->cmd_len = 16; memset(cmd->cmnd, 0, cmd->cmd_len); cmd->cmnd[0] = ZBC_OUT; cmd->cmnd[1] = ZO_RESET_WRITE_POINTER; put_unaligned_be64(block, &cmd->cmnd[2]); rq->timeout = SD_TIMEOUT; cmd->sc_data_direction = DMA_NONE; cmd->transfersize = 0; cmd->allowed = 0; return BLKPREP_OK; } /** * sd_zbc_write_lock_zone - Write lock a sequential zone. * @cmd: write command * * Called from sd_init_cmd() for write requests (standard write, write same or * write zeroes operations). If the request target zone is not already locked, * the zone is locked and BLKPREP_OK returned, allowing the request to proceed * through dispatch in scsi_request_fn(). Otherwise, BLKPREP_DEFER is returned, * forcing the request to wait for the zone to be unlocked, that is, for the * previously issued write request targeting the same zone to complete. * * This is called from blk_peek_request() context with the queue lock held and * before the request is removed from the scheduler. As a result, multiple * contexts executing concurrently scsi_request_fn() cannot result in write * sequence reordering as only a single write request per zone is allowed to * proceed. */ int sd_zbc_write_lock_zone(struct scsi_cmnd *cmd) { struct request *rq = cmd->request; struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); sector_t sector = blk_rq_pos(rq); sector_t zone_sectors = sd_zbc_zone_sectors(sdkp); unsigned int zno = sd_zbc_zone_no(sdkp, sector); /* * Note: Checks of the alignment of the write command on * logical blocks is done in sd.c */ /* Do not allow zone boundaries crossing on host-managed drives */ if (blk_queue_zoned_model(sdkp->disk->queue) == BLK_ZONED_HM && (sector & (zone_sectors - 1)) + blk_rq_sectors(rq) > zone_sectors) return BLKPREP_KILL; /* * Do not issue more than one write at a time per * zone. This solves write ordering problems due to * the unlocking of the request queue in the dispatch * path in the non scsi-mq case. */ if (sdkp->zones_wlock && test_and_set_bit(zno, sdkp->zones_wlock)) return BLKPREP_DEFER; WARN_ON_ONCE(cmd->flags & SCMD_ZONE_WRITE_LOCK); cmd->flags |= SCMD_ZONE_WRITE_LOCK; return BLKPREP_OK; } /** * sd_zbc_write_unlock_zone - Write unlock a sequential zone. * @cmd: write command * * Called from sd_uninit_cmd(). Unlocking the request target zone will allow * dispatching the next write request for the zone. */ void sd_zbc_write_unlock_zone(struct scsi_cmnd *cmd) { struct request *rq = cmd->request; struct scsi_disk *sdkp = scsi_disk(rq->rq_disk); if (sdkp->zones_wlock && cmd->flags & SCMD_ZONE_WRITE_LOCK) { unsigned int zno = sd_zbc_zone_no(sdkp, blk_rq_pos(rq)); WARN_ON_ONCE(!test_bit(zno, sdkp->zones_wlock)); cmd->flags &= ~SCMD_ZONE_WRITE_LOCK; clear_bit_unlock(zno, sdkp->zones_wlock); smp_mb__after_atomic(); } } /** * sd_zbc_complete - ZBC command post processing. * @cmd: Completed command * @good_bytes: Command reply bytes * @sshdr: command sense header * * Called from sd_done(). Process report zones reply and handle reset zone * and write commands errors. */ void sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes, struct scsi_sense_hdr *sshdr) { int result = cmd->result; struct request *rq = cmd->request; switch (req_op(rq)) { case REQ_OP_ZONE_RESET: if (result && sshdr->sense_key == ILLEGAL_REQUEST && sshdr->asc == 0x24) /* * INVALID FIELD IN CDB error: reset of a conventional * zone was attempted. Nothing to worry about, so be * quiet about the error. */ rq->rq_flags |= RQF_QUIET; break; case REQ_OP_WRITE: case REQ_OP_WRITE_ZEROES: case REQ_OP_WRITE_SAME: if (result && sshdr->sense_key == ILLEGAL_REQUEST && sshdr->asc == 0x21) /* * INVALID ADDRESS FOR WRITE error: It is unlikely that * retrying write requests failed with any kind of * alignement error will result in success. So don't. */ cmd->allowed = 0; break; case REQ_OP_ZONE_REPORT: if (!result) sd_zbc_report_zones_complete(cmd, good_bytes); break; } } /** * sd_zbc_read_zoned_characteristics - Read zoned block device characteristics * @sdkp: Target disk * @buf: Buffer where to store the VPD page data * * Read VPD page B6. */ static int sd_zbc_read_zoned_characteristics(struct scsi_disk *sdkp, unsigned char *buf) { if (scsi_get_vpd_page(sdkp->device, 0xb6, buf, 64)) { sd_printk(KERN_NOTICE, sdkp, "Unconstrained-read check failed\n"); return -ENODEV; } if (sdkp->device->type != TYPE_ZBC) { /* Host-aware */ sdkp->urswrz = 1; sdkp->zones_optimal_open = get_unaligned_be32(&buf[8]); sdkp->zones_optimal_nonseq = get_unaligned_be32(&buf[12]); sdkp->zones_max_open = 0; } else { /* Host-managed */ sdkp->urswrz = buf[4] & 1; sdkp->zones_optimal_open = 0; sdkp->zones_optimal_nonseq = 0; sdkp->zones_max_open = get_unaligned_be32(&buf[16]); } return 0; } /** * sd_zbc_check_capacity - Check reported capacity. * @sdkp: Target disk * @buf: Buffer to use for commands * * ZBC drive may report only the capacity of the first conventional zones at * LBA 0. This is indicated by the RC_BASIS field of the read capacity reply. * Check this here. If the disk reported only its conventional zones capacity, * get the total capacity by doing a report zones. */ static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf) { sector_t lba; int ret; if (sdkp->rc_basis != 0) return 0; /* Do a report zone to get the maximum LBA to check capacity */ ret = sd_zbc_report_zones(sdkp, buf, SD_BUF_SIZE, 0); if (ret) return ret; /* The max_lba field is the capacity of this device */ lba = get_unaligned_be64(&buf[8]); if (lba + 1 == sdkp->capacity) return 0; if (sdkp->first_scan) sd_printk(KERN_WARNING, sdkp, "Changing capacity from %llu to max LBA+1 %llu\n", (unsigned long long)sdkp->capacity, (unsigned long long)lba + 1); sdkp->capacity = lba + 1; return 0; } #define SD_ZBC_BUF_SIZE 131072U /** * sd_zbc_check_zone_size - Check the device zone sizes * @sdkp: Target disk * * Check that all zones of the device are equal. The last zone can however * be smaller. The zone size must also be a power of two number of LBAs. */ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp) { u64 zone_blocks; sector_t block = 0; unsigned char *buf; unsigned char *rec; unsigned int buf_len; unsigned int list_length; int ret; u8 same; sdkp->zone_blocks = 0; /* Get a buffer */ buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL); if (!buf) return -ENOMEM; /* Do a report zone to get the same field */ ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, 0); if (ret) { zone_blocks = 0; goto out; } same = buf[4] & 0x0f; if (same > 0) { rec = &buf[64]; zone_blocks = get_unaligned_be64(&rec[8]); goto out; } /* * Check the size of all zones: all zones must be of * equal size, except the last zone which can be smaller * than other zones. */ do { /* Parse REPORT ZONES header */ list_length = get_unaligned_be32(&buf[0]) + 64; rec = buf + 64; buf_len = min(list_length, SD_ZBC_BUF_SIZE); /* Parse zone descriptors */ while (rec < buf + buf_len) { zone_blocks = get_unaligned_be64(&rec[8]); if (sdkp->zone_blocks == 0) { sdkp->zone_blocks = zone_blocks; } else if (zone_blocks != sdkp->zone_blocks && (block + zone_blocks < sdkp->capacity || zone_blocks > sdkp->zone_blocks)) { zone_blocks = 0; goto out; } block += zone_blocks; rec += 64; } if (block < sdkp->capacity) { ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, block); if (ret) return ret; } } while (block < sdkp->capacity); zone_blocks = sdkp->zone_blocks; out: kfree(buf); if (!zone_blocks) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Devices with non constant zone " "size are not supported\n"); return -ENODEV; } if (!is_power_of_2(zone_blocks)) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Devices with non power of 2 zone " "size are not supported\n"); return -ENODEV; } if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "Zone size too large\n"); return -ENODEV; } sdkp->zone_blocks = zone_blocks; sdkp->zone_shift = ilog2(zone_blocks); return 0; } static int sd_zbc_setup(struct scsi_disk *sdkp) { /* READ16/WRITE16 is mandatory for ZBC disks */ sdkp->device->use_16_for_rw = 1; sdkp->device->use_10_for_rw = 0; /* chunk_sectors indicates the zone size */ blk_queue_chunk_sectors(sdkp->disk->queue, logical_to_sectors(sdkp->device, sdkp->zone_blocks)); sdkp->nr_zones = round_up(sdkp->capacity, sdkp->zone_blocks) >> sdkp->zone_shift; if (!sdkp->zones_wlock) { sdkp->zones_wlock = kcalloc(BITS_TO_LONGS(sdkp->nr_zones), sizeof(unsigned long), GFP_KERNEL); if (!sdkp->zones_wlock) return -ENOMEM; } return 0; } int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf) { int ret; if (!sd_is_zoned(sdkp)) /* * Device managed or normal SCSI disk, * no special handling required */ return 0; /* Get zoned block device characteristics */ ret = sd_zbc_read_zoned_characteristics(sdkp, buf); if (ret) goto err; /* * Check for unconstrained reads: host-managed devices with * constrained reads (drives failing read after write pointer) * are not supported. */ if (!sdkp->urswrz) { if (sdkp->first_scan) sd_printk(KERN_NOTICE, sdkp, "constrained reads devices are not supported\n"); ret = -ENODEV; goto err; } /* Check capacity */ ret = sd_zbc_check_capacity(sdkp, buf); if (ret) goto err; /* * Check zone size: only devices with a constant zone size (except * an eventual last runt zone) that is a power of 2 are supported. */ ret = sd_zbc_check_zone_size(sdkp); if (ret) goto err; /* The drive satisfies the kernel restrictions: set it up */ ret = sd_zbc_setup(sdkp); if (ret) goto err; return 0; err: sdkp->capacity = 0; return ret; } void sd_zbc_remove(struct scsi_disk *sdkp) { kfree(sdkp->zones_wlock); sdkp->zones_wlock = NULL; } void sd_zbc_print_zones(struct scsi_disk *sdkp) { if (!sd_is_zoned(sdkp) || !sdkp->capacity) return; if (sdkp->capacity & (sdkp->zone_blocks - 1)) sd_printk(KERN_NOTICE, sdkp, "%u zones of %u logical blocks + 1 runt zone\n", sdkp->nr_zones - 1, sdkp->zone_blocks); else sd_printk(KERN_NOTICE, sdkp, "%u zones of %u logical blocks\n", sdkp->nr_zones, sdkp->zone_blocks); }