// SPDX-License-Identifier: GPL-2.0-only
/*
* SCSI Zoned Block commands
*
* Copyright (C) 2014-2015 SUSE Linux GmbH
* Written by: Hannes Reinecke <[email protected]>
* Modified by: Damien Le Moal <[email protected]>
* Modified by: Shaun Tancheff <[email protected]>
*/
#include <linux/blkdev.h>
#include <linux/vmalloc.h>
#include <linux/sched/mm.h>
#include <linux/mutex.h>
#include <linux/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include "sd.h"
#define CREATE_TRACE_POINTS
#include "sd_trace.h"
/* 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;
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;
const struct scsi_exec_args exec_args = {
.sshdr = &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_cmd(sdp, cmd, REQ_OP_DRV_IN, buf, buflen,
timeout, SD_MAX_RETRIES, &exec_args);
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 (sdkp->device->type != TYPE_ZBC)
/* 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 (sdkp->device->type != TYPE_ZBC)
/* 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;
}
/**
* 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;
}
/**
* 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;
}
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 (sdkp->device->type != TYPE_ZBC || !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);
}
/*
* 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;
unsigned int flags;
int ret;
/*
* There is nothing to do for regular disks, including host-aware disks
* that have partitions.
*/
if (!blk_queue_is_zoned(q))
return 0;
if (sdkp->zone_info.zone_blocks == zone_blocks &&
sdkp->zone_info.nr_zones == nr_zones &&
disk->nr_zones == nr_zones)
return 0;
sdkp->zone_info.zone_blocks = zone_blocks;
sdkp->zone_info.nr_zones = nr_zones;
flags = memalloc_noio_save();
ret = blk_revalidate_disk_zones(disk);
memalloc_noio_restore(flags);
if (ret) {
sdkp->zone_info = (struct zoned_disk_info){ };
sdkp->capacity = 0;
return ret;
}
sd_zbc_print_zones(sdkp);
return 0;
}
/**
* sd_zbc_read_zones - Read zone information and update the request queue
* @sdkp: SCSI disk pointer.
* @lim: queue limits to read into
* @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, struct queue_limits *lim,
u8 buf[SD_BUF_SIZE])
{
unsigned int nr_zones;
u32 zone_blocks = 0;
int ret;
if (sdkp->device->type != TYPE_ZBC)
return 0;
lim->features |= BLK_FEAT_ZONED;
/*
* Per ZBC and ZAC specifications, writes in sequential write required
* zones of host-managed devices must be aligned to the device physical
* block size.
*/
lim->zone_write_granularity = sdkp->physical_block_size;
/* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
sdkp->device->use_16_for_rw = 1;
sdkp->device->use_10_for_rw = 0;
sdkp->device->use_16_for_sync = 1;
/* 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;
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;
/* The drive satisfies the kernel restrictions: set it up */
if (sdkp->zones_max_open == U32_MAX)
lim->max_open_zones = 0;
else
lim->max_open_zones = sdkp->zones_max_open;
lim->max_active_zones = 0;
lim->chunk_sectors = logical_to_sectors(sdkp->device, zone_blocks);
/* Enable block layer zone append emulation */
lim->max_zone_append_sectors = 0;
return 0;
err:
sdkp->capacity = 0;
return ret;
}
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