diff options
Diffstat (limited to 'drivers/scsi/sd_zbc.c')
| -rw-r--r-- | drivers/scsi/sd_zbc.c | 968 |
1 files changed, 968 insertions, 0 deletions
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c new file mode 100644 index 000000000..4c35b4a91 --- /dev/null +++ b/drivers/scsi/sd_zbc.c @@ -0,0 +1,968 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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> + */ + +#include <linux/blkdev.h> +#include <linux/vmalloc.h> +#include <linux/sched/mm.h> +#include <linux/mutex.h> + +#include <asm/unaligned.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_cmnd.h> + +#include "sd.h" + +/** + * sd_zbc_get_zone_wp_offset - Get zone write pointer offset. + * @zone: Zone for which to return the write pointer offset. + * + * Return: offset of the write pointer from the start of the zone. + */ +static unsigned int sd_zbc_get_zone_wp_offset(struct blk_zone *zone) +{ + if (zone->type == ZBC_ZONE_TYPE_CONV) + return 0; + + switch (zone->cond) { + case BLK_ZONE_COND_IMP_OPEN: + case BLK_ZONE_COND_EXP_OPEN: + case BLK_ZONE_COND_CLOSED: + return zone->wp - zone->start; + case BLK_ZONE_COND_FULL: + return zone->len; + case BLK_ZONE_COND_EMPTY: + case BLK_ZONE_COND_OFFLINE: + case BLK_ZONE_COND_READONLY: + default: + /* + * Offline and read-only zones do not have a valid + * write pointer. Use 0 as for an empty zone. + */ + return 0; + } +} + +/* Whether or not a SCSI zone descriptor describes a gap zone. */ +static bool sd_zbc_is_gap_zone(const u8 buf[64]) +{ + return (buf[0] & 0xf) == ZBC_ZONE_TYPE_GAP; +} + +/** + * sd_zbc_parse_report - Parse a SCSI zone descriptor + * @sdkp: SCSI disk pointer. + * @buf: SCSI zone descriptor. + * @idx: Index of the zone relative to the first zone reported by the current + * sd_zbc_report_zones() call. + * @cb: Callback function pointer. + * @data: Second argument passed to @cb. + * + * Return: Value returned by @cb. + * + * Convert a SCSI zone descriptor into struct blk_zone format. Additionally, + * call @cb(blk_zone, @data). + */ +static int sd_zbc_parse_report(struct scsi_disk *sdkp, const u8 buf[64], + unsigned int idx, report_zones_cb cb, void *data) +{ + struct scsi_device *sdp = sdkp->device; + struct blk_zone zone = { 0 }; + sector_t start_lba, gran; + int ret; + + if (WARN_ON_ONCE(sd_zbc_is_gap_zone(buf))) + return -EINVAL; + + 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; + + start_lba = get_unaligned_be64(&buf[16]); + zone.start = logical_to_sectors(sdp, start_lba); + zone.capacity = logical_to_sectors(sdp, get_unaligned_be64(&buf[8])); + zone.len = zone.capacity; + if (sdkp->zone_starting_lba_gran) { + gran = logical_to_sectors(sdp, sdkp->zone_starting_lba_gran); + if (zone.len > gran) { + sd_printk(KERN_ERR, sdkp, + "Invalid zone at LBA %llu with capacity %llu and length %llu; granularity = %llu\n", + start_lba, + sectors_to_logical(sdp, zone.capacity), + sectors_to_logical(sdp, zone.len), + sectors_to_logical(sdp, gran)); + return -EINVAL; + } + /* + * Use the starting LBA granularity instead of the zone length + * obtained from the REPORT ZONES command. + */ + zone.len = gran; + } + if (zone.cond == ZBC_ZONE_COND_FULL) + zone.wp = zone.start + zone.len; + else + zone.wp = logical_to_sectors(sdp, get_unaligned_be64(&buf[24])); + + ret = cb(&zone, idx, data); + if (ret) + return ret; + + if (sdkp->rev_wp_offset) + sdkp->rev_wp_offset[idx] = sd_zbc_get_zone_wp_offset(&zone); + + return 0; +} + +/** + * sd_zbc_do_report_zones - Issue a REPORT ZONES scsi command. + * @sdkp: The target disk + * @buf: vmalloc-ed buffer to use for the reply + * @buflen: the buffer size + * @lba: Start LBA of the report + * @partial: Do partial report + * + * For internal use during device validation. + * Using partial=true can significantly speed up execution of a report zones + * command because the disk does not have to count all possible report matching + * zones and will only report the count of zones fitting in the command reply + * buffer. + */ +static int sd_zbc_do_report_zones(struct scsi_disk *sdkp, unsigned char *buf, + unsigned int buflen, sector_t lba, + bool partial) +{ + 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]); + if (partial) + cmd[14] = ZBC_REPORT_ZONE_PARTIAL; + + 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 start lba %llu failed\n", lba); + sd_print_result(sdkp, "REPORT ZONES", result); + if (result > 0 && scsi_sense_valid(&sshdr)) + sd_print_sense_hdr(sdkp, &sshdr); + 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_alloc_report_buffer() - Allocate a buffer for report zones reply. + * @sdkp: The target disk + * @nr_zones: Maximum number of zones to report + * @buflen: Size of the buffer allocated + * + * Try to allocate a reply buffer for the number of requested zones. + * The size of the buffer allocated may be smaller than requested to + * satify the device constraint (max_hw_sectors, max_segments, etc). + * + * Return the address of the allocated buffer and update @buflen with + * the size of the allocated buffer. + */ +static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp, + unsigned int nr_zones, size_t *buflen) +{ + struct request_queue *q = sdkp->disk->queue; + size_t bufsize; + void *buf; + + /* + * Report zone buffer size should be at most 64B times the number of + * zones requested plus the 64B reply header, but should be aligned + * to SECTOR_SIZE for ATA devices. + * Make sure that this size does not exceed the hardware capabilities. + * Furthermore, since the report zone command cannot be split, make + * sure that the allocated buffer can always be mapped by limiting the + * number of pages allocated to the HBA max segments limit. + */ + nr_zones = min(nr_zones, sdkp->zone_info.nr_zones); + bufsize = roundup((nr_zones + 1) * 64, SECTOR_SIZE); + bufsize = min_t(size_t, bufsize, + queue_max_hw_sectors(q) << SECTOR_SHIFT); + bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT); + + while (bufsize >= SECTOR_SIZE) { + buf = __vmalloc(bufsize, + GFP_KERNEL | __GFP_ZERO | __GFP_NORETRY); + if (buf) { + *buflen = bufsize; + return buf; + } + bufsize = rounddown(bufsize >> 1, SECTOR_SIZE); + } + + return NULL; +} + +/** + * 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_info.zone_blocks); +} + +/** + * sd_zbc_report_zones - SCSI .report_zones() callback. + * @disk: Disk to report zones for. + * @sector: Start sector. + * @nr_zones: Maximum number of zones to report. + * @cb: Callback function called to report zone information. + * @data: Second argument passed to @cb. + * + * Called by the block layer to iterate over zone information. See also the + * disk->fops->report_zones() calls in block/blk-zoned.c. + */ +int sd_zbc_report_zones(struct gendisk *disk, sector_t sector, + unsigned int nr_zones, report_zones_cb cb, void *data) +{ + struct scsi_disk *sdkp = scsi_disk(disk); + sector_t lba = sectors_to_logical(sdkp->device, sector); + unsigned int nr, i; + unsigned char *buf; + u64 zone_length, start_lba; + size_t offset, buflen = 0; + int zone_idx = 0; + int ret; + + if (!sd_is_zoned(sdkp)) + /* Not a zoned device */ + return -EOPNOTSUPP; + + if (!sdkp->capacity) + /* Device gone or invalid */ + return -ENODEV; + + buf = sd_zbc_alloc_report_buffer(sdkp, nr_zones, &buflen); + if (!buf) + return -ENOMEM; + + while (zone_idx < nr_zones && lba < sdkp->capacity) { + ret = sd_zbc_do_report_zones(sdkp, buf, buflen, lba, true); + if (ret) + goto out; + + offset = 0; + nr = min(nr_zones, get_unaligned_be32(&buf[0]) / 64); + if (!nr) + break; + + for (i = 0; i < nr && zone_idx < nr_zones; i++) { + offset += 64; + start_lba = get_unaligned_be64(&buf[offset + 16]); + zone_length = get_unaligned_be64(&buf[offset + 8]); + if ((zone_idx == 0 && + (lba < start_lba || + lba >= start_lba + zone_length)) || + (zone_idx > 0 && start_lba != lba) || + start_lba + zone_length < start_lba) { + sd_printk(KERN_ERR, sdkp, + "Zone %d at LBA %llu is invalid: %llu + %llu\n", + zone_idx, lba, start_lba, zone_length); + ret = -EINVAL; + goto out; + } + lba = start_lba + zone_length; + if (sd_zbc_is_gap_zone(&buf[offset])) { + if (sdkp->zone_starting_lba_gran) + continue; + sd_printk(KERN_ERR, sdkp, + "Gap zone without constant LBA offsets\n"); + ret = -EINVAL; + goto out; + } + + ret = sd_zbc_parse_report(sdkp, buf + offset, zone_idx, + cb, data); + if (ret) + goto out; + + zone_idx++; + } + } + + ret = zone_idx; +out: + kvfree(buf); + return ret; +} + +static blk_status_t sd_zbc_cmnd_checks(struct scsi_cmnd *cmd) +{ + struct request *rq = scsi_cmd_to_rq(cmd); + struct scsi_disk *sdkp = scsi_disk(rq->q->disk); + sector_t sector = blk_rq_pos(rq); + + if (!sd_is_zoned(sdkp)) + /* Not a zoned device */ + return BLK_STS_IOERR; + + if (sdkp->device->changed) + return BLK_STS_IOERR; + + if (sector & (sd_zbc_zone_sectors(sdkp) - 1)) + /* Unaligned request */ + return BLK_STS_IOERR; + + return BLK_STS_OK; +} + +#define SD_ZBC_INVALID_WP_OFST (~0u) +#define SD_ZBC_UPDATING_WP_OFST (SD_ZBC_INVALID_WP_OFST - 1) + +static int sd_zbc_update_wp_offset_cb(struct blk_zone *zone, unsigned int idx, + void *data) +{ + struct scsi_disk *sdkp = data; + + lockdep_assert_held(&sdkp->zones_wp_offset_lock); + + sdkp->zones_wp_offset[idx] = sd_zbc_get_zone_wp_offset(zone); + + return 0; +} + +/* + * An attempt to append a zone triggered an invalid write pointer error. + * Reread the write pointer of the zone(s) in which the append failed. + */ +static void sd_zbc_update_wp_offset_workfn(struct work_struct *work) +{ + struct scsi_disk *sdkp; + unsigned long flags; + sector_t zno; + int ret; + + sdkp = container_of(work, struct scsi_disk, zone_wp_offset_work); + + spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags); + for (zno = 0; zno < sdkp->zone_info.nr_zones; zno++) { + if (sdkp->zones_wp_offset[zno] != SD_ZBC_UPDATING_WP_OFST) + continue; + + spin_unlock_irqrestore(&sdkp->zones_wp_offset_lock, flags); + ret = sd_zbc_do_report_zones(sdkp, sdkp->zone_wp_update_buf, + SD_BUF_SIZE, + zno * sdkp->zone_info.zone_blocks, true); + spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags); + if (!ret) + sd_zbc_parse_report(sdkp, sdkp->zone_wp_update_buf + 64, + zno, sd_zbc_update_wp_offset_cb, + sdkp); + } + spin_unlock_irqrestore(&sdkp->zones_wp_offset_lock, flags); + + scsi_device_put(sdkp->device); +} + +/** + * sd_zbc_prepare_zone_append() - Prepare an emulated ZONE_APPEND command. + * @cmd: the command to setup + * @lba: the LBA to patch + * @nr_blocks: the number of LBAs to be written + * + * Called from sd_setup_read_write_cmnd() for REQ_OP_ZONE_APPEND. + * @sd_zbc_prepare_zone_append() handles the necessary zone wrote locking and + * patching of the lba for an emulated ZONE_APPEND command. + * + * In case the cached write pointer offset is %SD_ZBC_INVALID_WP_OFST it will + * schedule a REPORT ZONES command and return BLK_STS_IOERR. + */ +blk_status_t sd_zbc_prepare_zone_append(struct scsi_cmnd *cmd, sector_t *lba, + unsigned int nr_blocks) +{ + struct request *rq = scsi_cmd_to_rq(cmd); + struct scsi_disk *sdkp = scsi_disk(rq->q->disk); + unsigned int wp_offset, zno = blk_rq_zone_no(rq); + unsigned long flags; + blk_status_t ret; + + ret = sd_zbc_cmnd_checks(cmd); + if (ret != BLK_STS_OK) + return ret; + + if (!blk_rq_zone_is_seq(rq)) + return BLK_STS_IOERR; + + /* Unlock of the write lock will happen in sd_zbc_complete() */ + if (!blk_req_zone_write_trylock(rq)) + return BLK_STS_ZONE_RESOURCE; + + spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags); + wp_offset = sdkp->zones_wp_offset[zno]; + switch (wp_offset) { + case SD_ZBC_INVALID_WP_OFST: + /* + * We are about to schedule work to update a zone write pointer + * offset, which will cause the zone append command to be + * requeued. So make sure that the scsi device does not go away + * while the work is being processed. + */ + if (scsi_device_get(sdkp->device)) { + ret = BLK_STS_IOERR; + break; + } + sdkp->zones_wp_offset[zno] = SD_ZBC_UPDATING_WP_OFST; + schedule_work(&sdkp->zone_wp_offset_work); + fallthrough; + case SD_ZBC_UPDATING_WP_OFST: + ret = BLK_STS_DEV_RESOURCE; + break; + default: + wp_offset = sectors_to_logical(sdkp->device, wp_offset); + if (wp_offset + nr_blocks > sdkp->zone_info.zone_blocks) { + ret = BLK_STS_IOERR; + break; + } + + *lba += wp_offset; + } + spin_unlock_irqrestore(&sdkp->zones_wp_offset_lock, flags); + if (ret) + blk_req_zone_write_unlock(rq); + return ret; +} + +/** + * sd_zbc_setup_zone_mgmt_cmnd - Prepare a zone ZBC_OUT command. The operations + * can be RESET WRITE POINTER, OPEN, CLOSE or FINISH. + * @cmd: the command to setup + * @op: Operation to be performed + * @all: All zones control + * + * Called from sd_init_command() for REQ_OP_ZONE_RESET, REQ_OP_ZONE_RESET_ALL, + * REQ_OP_ZONE_OPEN, REQ_OP_ZONE_CLOSE or REQ_OP_ZONE_FINISH requests. + */ +blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd, + unsigned char op, bool all) +{ + struct request *rq = scsi_cmd_to_rq(cmd); + sector_t sector = blk_rq_pos(rq); + struct scsi_disk *sdkp = scsi_disk(rq->q->disk); + sector_t block = sectors_to_logical(sdkp->device, sector); + blk_status_t ret; + + ret = sd_zbc_cmnd_checks(cmd); + if (ret != BLK_STS_OK) + return ret; + + cmd->cmd_len = 16; + memset(cmd->cmnd, 0, cmd->cmd_len); + cmd->cmnd[0] = ZBC_OUT; + cmd->cmnd[1] = op; + if (all) + cmd->cmnd[14] = 0x1; + else + put_unaligned_be64(block, &cmd->cmnd[2]); + + rq->timeout = SD_TIMEOUT; + cmd->sc_data_direction = DMA_NONE; + cmd->transfersize = 0; + cmd->allowed = 0; + + return BLK_STS_OK; +} + +static bool sd_zbc_need_zone_wp_update(struct request *rq) +{ + switch (req_op(rq)) { + case REQ_OP_ZONE_APPEND: + case REQ_OP_ZONE_FINISH: + case REQ_OP_ZONE_RESET: + case REQ_OP_ZONE_RESET_ALL: + return true; + case REQ_OP_WRITE: + case REQ_OP_WRITE_ZEROES: + return blk_rq_zone_is_seq(rq); + default: + return false; + } +} + +/** + * sd_zbc_zone_wp_update - Update cached zone write pointer upon cmd completion + * @cmd: Completed command + * @good_bytes: Command reply bytes + * + * Called from sd_zbc_complete() to handle the update of the cached zone write + * pointer value in case an update is needed. + */ +static unsigned int sd_zbc_zone_wp_update(struct scsi_cmnd *cmd, + unsigned int good_bytes) +{ + int result = cmd->result; + struct request *rq = scsi_cmd_to_rq(cmd); + struct scsi_disk *sdkp = scsi_disk(rq->q->disk); + unsigned int zno = blk_rq_zone_no(rq); + enum req_op op = req_op(rq); + unsigned long flags; + + /* + * If we got an error for a command that needs updating the write + * pointer offset cache, we must mark the zone wp offset entry as + * invalid to force an update from disk the next time a zone append + * command is issued. + */ + spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags); + + if (result && op != REQ_OP_ZONE_RESET_ALL) { + if (op == REQ_OP_ZONE_APPEND) { + /* Force complete completion (no retry) */ + good_bytes = 0; + scsi_set_resid(cmd, blk_rq_bytes(rq)); + } + + /* + * Force an update of the zone write pointer offset on + * the next zone append access. + */ + if (sdkp->zones_wp_offset[zno] != SD_ZBC_UPDATING_WP_OFST) + sdkp->zones_wp_offset[zno] = SD_ZBC_INVALID_WP_OFST; + goto unlock_wp_offset; + } + + switch (op) { + case REQ_OP_ZONE_APPEND: + rq->__sector += sdkp->zones_wp_offset[zno]; + fallthrough; + case REQ_OP_WRITE_ZEROES: + case REQ_OP_WRITE: + if (sdkp->zones_wp_offset[zno] < sd_zbc_zone_sectors(sdkp)) + sdkp->zones_wp_offset[zno] += + good_bytes >> SECTOR_SHIFT; + break; + case REQ_OP_ZONE_RESET: + sdkp->zones_wp_offset[zno] = 0; + break; + case REQ_OP_ZONE_FINISH: + sdkp->zones_wp_offset[zno] = sd_zbc_zone_sectors(sdkp); + break; + case REQ_OP_ZONE_RESET_ALL: + memset(sdkp->zones_wp_offset, 0, + sdkp->zone_info.nr_zones * sizeof(unsigned int)); + break; + default: + break; + } + +unlock_wp_offset: + spin_unlock_irqrestore(&sdkp->zones_wp_offset_lock, flags); + + return good_bytes; +} + +/** + * sd_zbc_complete - ZBC command post processing. + * @cmd: Completed command + * @good_bytes: Command reply bytes + * @sshdr: command sense header + * + * Called from sd_done() to handle zone commands errors and updates to the + * device queue zone write pointer offset cahce. + */ +unsigned int sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes, + struct scsi_sense_hdr *sshdr) +{ + int result = cmd->result; + struct request *rq = scsi_cmd_to_rq(cmd); + + if (op_is_zone_mgmt(req_op(rq)) && + result && + sshdr->sense_key == ILLEGAL_REQUEST && + sshdr->asc == 0x24) { + /* + * INVALID FIELD IN CDB error: a zone management command was + * attempted on a conventional zone. Nothing to worry about, + * so be quiet about the error. + */ + rq->rq_flags |= RQF_QUIET; + } else if (sd_zbc_need_zone_wp_update(rq)) + good_bytes = sd_zbc_zone_wp_update(cmd, good_bytes); + + if (req_op(rq) == REQ_OP_ZONE_APPEND) + blk_req_zone_write_unlock(rq); + + return good_bytes; +} + +/** + * sd_zbc_check_zoned_characteristics - Check zoned block device characteristics + * @sdkp: Target disk + * @buf: Buffer where to store the VPD page data + * + * Read VPD page B6, get information and check that reads are unconstrained. + */ +static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp, + unsigned char *buf) +{ + u64 zone_starting_lba_gran; + + if (scsi_get_vpd_page(sdkp->device, 0xb6, buf, 64)) { + sd_printk(KERN_NOTICE, sdkp, + "Read zoned characteristics VPD page 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; + return 0; + } + + /* 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]); + /* Check zone alignment method */ + switch (buf[23] & 0xf) { + case 0: + case ZBC_CONSTANT_ZONE_LENGTH: + /* Use zone length */ + break; + case ZBC_CONSTANT_ZONE_START_OFFSET: + zone_starting_lba_gran = get_unaligned_be64(&buf[24]); + if (zone_starting_lba_gran == 0 || + !is_power_of_2(zone_starting_lba_gran) || + logical_to_sectors(sdkp->device, zone_starting_lba_gran) > + UINT_MAX) { + sd_printk(KERN_ERR, sdkp, + "Invalid zone starting LBA granularity %llu\n", + zone_starting_lba_gran); + return -ENODEV; + } + sdkp->zone_starting_lba_gran = zone_starting_lba_gran; + break; + default: + sd_printk(KERN_ERR, sdkp, "Invalid zone alignment method\n"); + return -ENODEV; + } + + /* + * 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"); + return -ENODEV; + } + + return 0; +} + +/** + * sd_zbc_check_capacity - Check the device capacity + * @sdkp: Target disk + * @buf: command buffer + * @zblocks: zone size in logical blocks + * + * Get the device zone size and check that the device capacity as reported + * by READ CAPACITY matches the max_lba value (plus one) of the report zones + * command reply for devices with RC_BASIS == 0. + * + * Returns 0 upon success or an error code upon failure. + */ +static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf, + u32 *zblocks) +{ + u64 zone_blocks; + sector_t max_lba; + unsigned char *rec; + int ret; + + /* Do a report zone to get max_lba and the size of the first zone */ + ret = sd_zbc_do_report_zones(sdkp, buf, SD_BUF_SIZE, 0, false); + if (ret) + return ret; + + if (sdkp->rc_basis == 0) { + /* The max_lba field is the capacity of this device */ + max_lba = get_unaligned_be64(&buf[8]); + if (sdkp->capacity != max_lba + 1) { + 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)max_lba + 1); + sdkp->capacity = max_lba + 1; + } + } + + if (sdkp->zone_starting_lba_gran == 0) { + /* Get the size of the first reported zone */ + rec = buf + 64; + zone_blocks = get_unaligned_be64(&rec[8]); + 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 -EFBIG; + } + } else { + zone_blocks = sdkp->zone_starting_lba_gran; + } + + if (!is_power_of_2(zone_blocks)) { + sd_printk(KERN_ERR, sdkp, + "Zone size %llu is not a power of two.\n", + zone_blocks); + return -EINVAL; + } + + *zblocks = zone_blocks; + + return 0; +} + +static void sd_zbc_print_zones(struct scsi_disk *sdkp) +{ + if (!sd_is_zoned(sdkp) || !sdkp->capacity) + return; + + if (sdkp->capacity & (sdkp->zone_info.zone_blocks - 1)) + sd_printk(KERN_NOTICE, sdkp, + "%u zones of %u logical blocks + 1 runt zone\n", + sdkp->zone_info.nr_zones - 1, + sdkp->zone_info.zone_blocks); + else + sd_printk(KERN_NOTICE, sdkp, + "%u zones of %u logical blocks\n", + sdkp->zone_info.nr_zones, + sdkp->zone_info.zone_blocks); +} + +static int sd_zbc_init_disk(struct scsi_disk *sdkp) +{ + sdkp->zones_wp_offset = NULL; + spin_lock_init(&sdkp->zones_wp_offset_lock); + sdkp->rev_wp_offset = NULL; + mutex_init(&sdkp->rev_mutex); + INIT_WORK(&sdkp->zone_wp_offset_work, sd_zbc_update_wp_offset_workfn); + sdkp->zone_wp_update_buf = kzalloc(SD_BUF_SIZE, GFP_KERNEL); + if (!sdkp->zone_wp_update_buf) + return -ENOMEM; + + return 0; +} + +void sd_zbc_free_zone_info(struct scsi_disk *sdkp) +{ + if (!sdkp->zone_wp_update_buf) + return; + + /* Serialize against revalidate zones */ + mutex_lock(&sdkp->rev_mutex); + + kvfree(sdkp->zones_wp_offset); + sdkp->zones_wp_offset = NULL; + kfree(sdkp->zone_wp_update_buf); + sdkp->zone_wp_update_buf = NULL; + + sdkp->early_zone_info = (struct zoned_disk_info){ }; + sdkp->zone_info = (struct zoned_disk_info){ }; + + mutex_unlock(&sdkp->rev_mutex); +} + +static void sd_zbc_revalidate_zones_cb(struct gendisk *disk) +{ + struct scsi_disk *sdkp = scsi_disk(disk); + + swap(sdkp->zones_wp_offset, sdkp->rev_wp_offset); +} + +/* + * Call blk_revalidate_disk_zones() if any of the zoned disk properties have + * changed that make it necessary to call that function. Called by + * sd_revalidate_disk() after the gendisk capacity has been set. + */ +int sd_zbc_revalidate_zones(struct scsi_disk *sdkp) +{ + struct gendisk *disk = sdkp->disk; + struct request_queue *q = disk->queue; + u32 zone_blocks = sdkp->early_zone_info.zone_blocks; + unsigned int nr_zones = sdkp->early_zone_info.nr_zones; + u32 max_append; + int ret = 0; + unsigned int flags; + + /* + * For all zoned disks, initialize zone append emulation data if not + * already done. This is necessary also for host-aware disks used as + * regular disks due to the presence of partitions as these partitions + * may be deleted and the disk zoned model changed back from + * BLK_ZONED_NONE to BLK_ZONED_HA. + */ + if (sd_is_zoned(sdkp) && !sdkp->zone_wp_update_buf) { + ret = sd_zbc_init_disk(sdkp); + if (ret) + return ret; + } + + /* + * There is nothing to do for regular disks, including host-aware disks + * that have partitions. + */ + if (!blk_queue_is_zoned(q)) + return 0; + + /* + * Make sure revalidate zones are serialized to ensure exclusive + * updates of the scsi disk data. + */ + mutex_lock(&sdkp->rev_mutex); + + if (sdkp->zone_info.zone_blocks == zone_blocks && + sdkp->zone_info.nr_zones == nr_zones && + disk->nr_zones == nr_zones) + goto unlock; + + flags = memalloc_noio_save(); + sdkp->zone_info.zone_blocks = zone_blocks; + sdkp->zone_info.nr_zones = nr_zones; + sdkp->rev_wp_offset = kvcalloc(nr_zones, sizeof(u32), GFP_KERNEL); + if (!sdkp->rev_wp_offset) { + ret = -ENOMEM; + memalloc_noio_restore(flags); + goto unlock; + } + + ret = blk_revalidate_disk_zones(disk, sd_zbc_revalidate_zones_cb); + + memalloc_noio_restore(flags); + kvfree(sdkp->rev_wp_offset); + sdkp->rev_wp_offset = NULL; + + if (ret) { + sdkp->zone_info = (struct zoned_disk_info){ }; + sdkp->capacity = 0; + goto unlock; + } + + max_append = min_t(u32, logical_to_sectors(sdkp->device, zone_blocks), + q->limits.max_segments << (PAGE_SHIFT - 9)); + max_append = min_t(u32, max_append, queue_max_hw_sectors(q)); + + blk_queue_max_zone_append_sectors(q, max_append); + + sd_zbc_print_zones(sdkp); + +unlock: + mutex_unlock(&sdkp->rev_mutex); + + return ret; +} + +/** + * sd_zbc_read_zones - Read zone information and update the request queue + * @sdkp: SCSI disk pointer. + * @buf: 512 byte buffer used for storing SCSI command output. + * + * Read zone information and update the request queue zone characteristics and + * also the zoned device information in *sdkp. Called by sd_revalidate_disk() + * before the gendisk capacity has been set. + */ +int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE]) +{ + struct gendisk *disk = sdkp->disk; + struct request_queue *q = disk->queue; + unsigned int nr_zones; + u32 zone_blocks = 0; + int ret; + + if (!sd_is_zoned(sdkp)) { + /* + * Device managed or normal SCSI disk, no special handling + * required. Nevertheless, free the disk zone information in + * case the device type changed. + */ + sd_zbc_free_zone_info(sdkp); + return 0; + } + + /* READ16/WRITE16 is mandatory for ZBC disks */ + sdkp->device->use_16_for_rw = 1; + sdkp->device->use_10_for_rw = 0; + + if (!blk_queue_is_zoned(q)) { + /* + * This can happen for a host aware disk with partitions. + * The block device zone model was already cleared by + * disk_set_zoned(). Only free the scsi disk zone + * information and exit early. + */ + sd_zbc_free_zone_info(sdkp); + return 0; + } + + /* Check zoned block device characteristics (unconstrained reads) */ + ret = sd_zbc_check_zoned_characteristics(sdkp, buf); + if (ret) + goto err; + + /* Check the device capacity reported by report zones */ + ret = sd_zbc_check_capacity(sdkp, buf, &zone_blocks); + if (ret != 0) + goto err; + + /* The drive satisfies the kernel restrictions: set it up */ + blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q); + blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE); + if (sdkp->zones_max_open == U32_MAX) + disk_set_max_open_zones(disk, 0); + else + disk_set_max_open_zones(disk, sdkp->zones_max_open); + disk_set_max_active_zones(disk, 0); + nr_zones = round_up(sdkp->capacity, zone_blocks) >> ilog2(zone_blocks); + + sdkp->early_zone_info.nr_zones = nr_zones; + sdkp->early_zone_info.zone_blocks = zone_blocks; + + return 0; + +err: + sdkp->capacity = 0; + + return ret; +} |