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|
// SPDX-License-Identifier: GPL-2.0
/*
* Zoned block device handling
*
* Copyright (c) 2015, Hannes Reinecke
* Copyright (c) 2015, SUSE Linux GmbH
*
* Copyright (c) 2016, Damien Le Moal
* Copyright (c) 2016, Western Digital
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rbtree.h>
#include <linux/blkdev.h>
#include <linux/blk-mq.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/sched/mm.h>
#include "blk.h"
static inline sector_t blk_zone_start(struct request_queue *q,
sector_t sector)
{
sector_t zone_mask = blk_queue_zone_sectors(q) - 1;
return sector & ~zone_mask;
}
/*
* Return true if a request is a write requests that needs zone write locking.
*/
bool blk_req_needs_zone_write_lock(struct request *rq)
{
if (!rq->q->seq_zones_wlock)
return false;
if (blk_rq_is_passthrough(rq))
return false;
switch (req_op(rq)) {
case REQ_OP_WRITE_ZEROES:
case REQ_OP_WRITE_SAME:
case REQ_OP_WRITE:
return blk_rq_zone_is_seq(rq);
default:
return false;
}
}
EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);
void __blk_req_zone_write_lock(struct request *rq)
{
if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq),
rq->q->seq_zones_wlock)))
return;
WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
rq->rq_flags |= RQF_ZONE_WRITE_LOCKED;
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_lock);
void __blk_req_zone_write_unlock(struct request *rq)
{
rq->rq_flags &= ~RQF_ZONE_WRITE_LOCKED;
if (rq->q->seq_zones_wlock)
WARN_ON_ONCE(!test_and_clear_bit(blk_rq_zone_no(rq),
rq->q->seq_zones_wlock));
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);
static inline unsigned int __blkdev_nr_zones(struct request_queue *q,
sector_t nr_sectors)
{
sector_t zone_sectors = blk_queue_zone_sectors(q);
return (nr_sectors + zone_sectors - 1) >> ilog2(zone_sectors);
}
/**
* blkdev_nr_zones - Get number of zones
* @bdev: Target block device
*
* Description:
* Return the total number of zones of a zoned block device.
* For a regular block device, the number of zones is always 0.
*/
unsigned int blkdev_nr_zones(struct block_device *bdev)
{
struct request_queue *q = bdev_get_queue(bdev);
if (!blk_queue_is_zoned(q))
return 0;
return __blkdev_nr_zones(q, bdev->bd_part->nr_sects);
}
EXPORT_SYMBOL_GPL(blkdev_nr_zones);
/*
* Check that a zone report belongs to this partition, and if yes, fix its start
* sector and write pointer and return true. Return false otherwise.
*/
static bool blkdev_report_zone(struct block_device *bdev, struct blk_zone *rep)
{
sector_t offset = get_start_sect(bdev);
if (rep->start < offset)
return false;
rep->start -= offset;
if (rep->start + rep->len > bdev->bd_part->nr_sects)
return false;
if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL)
rep->wp = rep->start + rep->len;
else
rep->wp -= offset;
return true;
}
static int blk_report_zones(struct gendisk *disk, sector_t sector,
struct blk_zone *zones, unsigned int *nr_zones)
{
struct request_queue *q = disk->queue;
unsigned int z = 0, n, nrz = *nr_zones;
sector_t capacity = get_capacity(disk);
int ret;
while (z < nrz && sector < capacity) {
n = nrz - z;
ret = disk->fops->report_zones(disk, sector, &zones[z], &n);
if (ret)
return ret;
if (!n)
break;
sector += blk_queue_zone_sectors(q) * n;
z += n;
}
WARN_ON(z > *nr_zones);
*nr_zones = z;
return 0;
}
/**
* blkdev_report_zones - Get zones information
* @bdev: Target block device
* @sector: Sector from which to report zones
* @zones: Array of zone structures where to return the zones information
* @nr_zones: Number of zone structures in the zone array
*
* Description:
* Get zone information starting from the zone containing @sector.
* The number of zone information reported may be less than the number
* requested by @nr_zones. The number of zones actually reported is
* returned in @nr_zones.
* The caller must use memalloc_noXX_save/restore() calls to control
* memory allocations done within this function (zone array and command
* buffer allocation by the device driver).
*/
int blkdev_report_zones(struct block_device *bdev, sector_t sector,
struct blk_zone *zones, unsigned int *nr_zones)
{
struct request_queue *q = bdev_get_queue(bdev);
unsigned int i, nrz;
int ret;
if (!blk_queue_is_zoned(q))
return -EOPNOTSUPP;
/*
* A block device that advertized itself as zoned must have a
* report_zones method. If it does not have one defined, the device
* driver has a bug. So warn about that.
*/
if (WARN_ON_ONCE(!bdev->bd_disk->fops->report_zones))
return -EOPNOTSUPP;
if (!*nr_zones || sector >= bdev->bd_part->nr_sects) {
*nr_zones = 0;
return 0;
}
nrz = min(*nr_zones,
__blkdev_nr_zones(q, bdev->bd_part->nr_sects - sector));
ret = blk_report_zones(bdev->bd_disk, get_start_sect(bdev) + sector,
zones, &nrz);
if (ret)
return ret;
for (i = 0; i < nrz; i++) {
if (!blkdev_report_zone(bdev, zones))
break;
zones++;
}
*nr_zones = i;
return 0;
}
EXPORT_SYMBOL_GPL(blkdev_report_zones);
static inline bool blkdev_allow_reset_all_zones(struct block_device *bdev,
sector_t sector,
sector_t nr_sectors)
{
if (!blk_queue_zone_resetall(bdev_get_queue(bdev)))
return false;
if (sector || nr_sectors != part_nr_sects_read(bdev->bd_part))
return false;
/*
* REQ_OP_ZONE_RESET_ALL can be executed only if the block device is
* the entire disk, that is, if the blocks device start offset is 0 and
* its capacity is the same as the entire disk.
*/
return get_start_sect(bdev) == 0 &&
part_nr_sects_read(bdev->bd_part) == get_capacity(bdev->bd_disk);
}
/**
* blkdev_zone_mgmt - Execute a zone management operation on a range of zones
* @bdev: Target block device
* @op: Operation to be performed on the zones
* @sector: Start sector of the first zone to operate on
* @nr_sectors: Number of sectors, should be at least the length of one zone and
* must be zone size aligned.
* @gfp_mask: Memory allocation flags (for bio_alloc)
*
* Description:
* Perform the specified operation on the range of zones specified by
* @sector..@sector+@nr_sectors. Specifying the entire disk sector range
* is valid, but the specified range should not contain conventional zones.
* The operation to execute on each zone can be a zone reset, open, close
* or finish request.
*/
int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
sector_t sector, sector_t nr_sectors,
gfp_t gfp_mask)
{
struct request_queue *q = bdev_get_queue(bdev);
sector_t zone_sectors = blk_queue_zone_sectors(q);
sector_t end_sector = sector + nr_sectors;
struct bio *bio = NULL;
int ret;
if (!blk_queue_is_zoned(q))
return -EOPNOTSUPP;
if (bdev_read_only(bdev))
return -EPERM;
if (!op_is_zone_mgmt(op))
return -EOPNOTSUPP;
if (!nr_sectors || end_sector > bdev->bd_part->nr_sects)
/* Out of range */
return -EINVAL;
/* Check alignment (handle eventual smaller last zone) */
if (sector & (zone_sectors - 1))
return -EINVAL;
if ((nr_sectors & (zone_sectors - 1)) &&
end_sector != bdev->bd_part->nr_sects)
return -EINVAL;
while (sector < end_sector) {
bio = blk_next_bio(bio, 0, gfp_mask);
bio_set_dev(bio, bdev);
/*
* Special case for the zone reset operation that reset all
* zones, this is useful for applications like mkfs.
*/
if (op == REQ_OP_ZONE_RESET &&
blkdev_allow_reset_all_zones(bdev, sector, nr_sectors)) {
bio->bi_opf = REQ_OP_ZONE_RESET_ALL;
break;
}
bio->bi_opf = op;
bio->bi_iter.bi_sector = sector;
sector += zone_sectors;
/* This may take a while, so be nice to others */
cond_resched();
}
ret = submit_bio_wait(bio);
bio_put(bio);
return ret;
}
EXPORT_SYMBOL_GPL(blkdev_zone_mgmt);
/*
* BLKREPORTZONE ioctl processing.
* Called from blkdev_ioctl.
*/
int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
struct request_queue *q;
struct blk_zone_report rep;
struct blk_zone *zones;
int ret;
if (!argp)
return -EINVAL;
q = bdev_get_queue(bdev);
if (!q)
return -ENXIO;
if (!blk_queue_is_zoned(q))
return -ENOTTY;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
return -EFAULT;
if (!rep.nr_zones)
return -EINVAL;
rep.nr_zones = min(blkdev_nr_zones(bdev), rep.nr_zones);
zones = kvmalloc_array(rep.nr_zones, sizeof(struct blk_zone),
GFP_KERNEL | __GFP_ZERO);
if (!zones)
return -ENOMEM;
ret = blkdev_report_zones(bdev, rep.sector, zones, &rep.nr_zones);
if (ret)
goto out;
if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) {
ret = -EFAULT;
goto out;
}
if (rep.nr_zones) {
if (copy_to_user(argp + sizeof(struct blk_zone_report), zones,
sizeof(struct blk_zone) * rep.nr_zones))
ret = -EFAULT;
}
out:
kvfree(zones);
return ret;
}
/*
* BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE and BLKFINISHZONE ioctl processing.
* Called from blkdev_ioctl.
*/
int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
struct request_queue *q;
struct blk_zone_range zrange;
enum req_opf op;
if (!argp)
return -EINVAL;
q = bdev_get_queue(bdev);
if (!q)
return -ENXIO;
if (!blk_queue_is_zoned(q))
return -ENOTTY;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (!(mode & FMODE_WRITE))
return -EBADF;
if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range)))
return -EFAULT;
switch (cmd) {
case BLKRESETZONE:
op = REQ_OP_ZONE_RESET;
break;
case BLKOPENZONE:
op = REQ_OP_ZONE_OPEN;
break;
case BLKCLOSEZONE:
op = REQ_OP_ZONE_CLOSE;
break;
case BLKFINISHZONE:
op = REQ_OP_ZONE_FINISH;
break;
default:
return -ENOTTY;
}
return blkdev_zone_mgmt(bdev, op, zrange.sector, zrange.nr_sectors,
GFP_KERNEL);
}
static inline unsigned long *blk_alloc_zone_bitmap(int node,
unsigned int nr_zones)
{
return kcalloc_node(BITS_TO_LONGS(nr_zones), sizeof(unsigned long),
GFP_NOIO, node);
}
/*
* Allocate an array of struct blk_zone to get nr_zones zone information.
* The allocated array may be smaller than nr_zones.
*/
static struct blk_zone *blk_alloc_zones(unsigned int *nr_zones)
{
struct blk_zone *zones;
size_t nrz = min(*nr_zones, BLK_ZONED_REPORT_MAX_ZONES);
/*
* GFP_KERNEL here is meaningless as the caller task context has
* the PF_MEMALLOC_NOIO flag set in blk_revalidate_disk_zones()
* with memalloc_noio_save().
*/
zones = kvcalloc(nrz, sizeof(struct blk_zone), GFP_KERNEL);
if (!zones) {
*nr_zones = 0;
return NULL;
}
*nr_zones = nrz;
return zones;
}
void blk_queue_free_zone_bitmaps(struct request_queue *q)
{
kfree(q->seq_zones_bitmap);
q->seq_zones_bitmap = NULL;
kfree(q->seq_zones_wlock);
q->seq_zones_wlock = NULL;
}
/*
* Helper function to check the validity of zones of a zoned block device.
*/
static bool blk_zone_valid(struct gendisk *disk, struct blk_zone *zone,
sector_t *sector)
{
struct request_queue *q = disk->queue;
sector_t zone_sectors = blk_queue_zone_sectors(q);
sector_t capacity = get_capacity(disk);
/*
* All zones must have the same size, with the exception on an eventual
* smaller last zone.
*/
if (zone->start + zone_sectors < capacity &&
zone->len != zone_sectors) {
pr_warn("%s: Invalid zoned device with non constant zone size\n",
disk->disk_name);
return false;
}
if (zone->start + zone->len >= capacity &&
zone->len > zone_sectors) {
pr_warn("%s: Invalid zoned device with larger last zone size\n",
disk->disk_name);
return false;
}
/* Check for holes in the zone report */
if (zone->start != *sector) {
pr_warn("%s: Zone gap at sectors %llu..%llu\n",
disk->disk_name, *sector, zone->start);
return false;
}
/* Check zone type */
switch (zone->type) {
case BLK_ZONE_TYPE_CONVENTIONAL:
case BLK_ZONE_TYPE_SEQWRITE_REQ:
case BLK_ZONE_TYPE_SEQWRITE_PREF:
break;
default:
pr_warn("%s: Invalid zone type 0x%x at sectors %llu\n",
disk->disk_name, (int)zone->type, zone->start);
return false;
}
*sector += zone->len;
return true;
}
/**
* blk_revalidate_disk_zones - (re)allocate and initialize zone bitmaps
* @disk: Target disk
*
* Helper function for low-level device drivers to (re) allocate and initialize
* a disk request queue zone bitmaps. This functions should normally be called
* within the disk ->revalidate method. For BIO based queues, no zone bitmap
* is allocated.
*/
int blk_revalidate_disk_zones(struct gendisk *disk)
{
struct request_queue *q = disk->queue;
unsigned int nr_zones = __blkdev_nr_zones(q, get_capacity(disk));
unsigned long *seq_zones_wlock = NULL, *seq_zones_bitmap = NULL;
unsigned int i, rep_nr_zones = 0, z = 0, nrz;
struct blk_zone *zones = NULL;
unsigned int noio_flag;
sector_t sector = 0;
int ret = 0;
if (WARN_ON_ONCE(!blk_queue_is_zoned(q)))
return -EIO;
/*
* BIO based queues do not use a scheduler so only q->nr_zones
* needs to be updated so that the sysfs exposed value is correct.
*/
if (!queue_is_mq(q)) {
q->nr_zones = nr_zones;
return 0;
}
/*
* Ensure that all memory allocations in this context are done as
* if GFP_NOIO was specified.
*/
noio_flag = memalloc_noio_save();
if (!nr_zones)
goto update;
/* Allocate bitmaps */
ret = -ENOMEM;
seq_zones_wlock = blk_alloc_zone_bitmap(q->node, nr_zones);
if (!seq_zones_wlock)
goto out;
seq_zones_bitmap = blk_alloc_zone_bitmap(q->node, nr_zones);
if (!seq_zones_bitmap)
goto out;
/*
* Get zone information to check the zones and initialize
* seq_zones_bitmap.
*/
rep_nr_zones = nr_zones;
zones = blk_alloc_zones(&rep_nr_zones);
if (!zones)
goto out;
while (z < nr_zones) {
nrz = min(nr_zones - z, rep_nr_zones);
ret = blk_report_zones(disk, sector, zones, &nrz);
if (ret)
goto out;
if (!nrz)
break;
for (i = 0; i < nrz; i++) {
if (!blk_zone_valid(disk, &zones[i], §or)) {
ret = -ENODEV;
goto out;
}
if (zones[i].type != BLK_ZONE_TYPE_CONVENTIONAL)
set_bit(z, seq_zones_bitmap);
z++;
}
}
if (WARN_ON(z != nr_zones)) {
ret = -EIO;
goto out;
}
update:
/*
* Install the new bitmaps, making sure the queue is stopped and
* all I/Os are completed (i.e. a scheduler is not referencing the
* bitmaps).
*/
blk_mq_freeze_queue(q);
q->nr_zones = nr_zones;
swap(q->seq_zones_wlock, seq_zones_wlock);
swap(q->seq_zones_bitmap, seq_zones_bitmap);
blk_mq_unfreeze_queue(q);
out:
memalloc_noio_restore(noio_flag);
kvfree(zones);
kfree(seq_zones_wlock);
kfree(seq_zones_bitmap);
if (ret) {
pr_warn("%s: failed to revalidate zones\n", disk->disk_name);
blk_mq_freeze_queue(q);
blk_queue_free_zone_bitmaps(q);
blk_mq_unfreeze_queue(q);
}
return ret;
}
EXPORT_SYMBOL_GPL(blk_revalidate_disk_zones);
|