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-rw-r--r--drivers/scsi/sd_zbc.c968
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;
+}