[v5,02/28] btrfs: Get zone information of zoned block devices
diff mbox series

Message ID 20191204081735.852438-3-naohiro.aota@wdc.com
State New
Headers show
Series
  • btrfs: zoned block device support
Related show

Commit Message

Naohiro Aota Dec. 4, 2019, 8:17 a.m. UTC
If a zoned block device is found, get its zone information (number of zones
and zone size) using the new helper function btrfs_get_dev_zone_info().  To
avoid costly run-time zone report commands to test the device zones type
during block allocation, attach the seq_zones bitmap to the device
structure to indicate if a zone is sequential or accept random writes. Also
it attaches the empty_zones bitmap to indicate if a zone is empty or not.

This patch also introduces the helper function btrfs_dev_is_sequential() to
test if the zone storing a block is a sequential write required zone and
btrfs_dev_is_empty_zone() to test if the zone is a empty zone.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/Makefile  |   1 +
 fs/btrfs/hmzoned.c | 174 +++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/hmzoned.h |  92 ++++++++++++++++++++++++
 fs/btrfs/volumes.c |  18 ++++-
 fs/btrfs/volumes.h |   4 ++
 5 files changed, 287 insertions(+), 2 deletions(-)
 create mode 100644 fs/btrfs/hmzoned.c
 create mode 100644 fs/btrfs/hmzoned.h

Comments

Johannes Thumshirn Dec. 4, 2019, 3:37 p.m. UTC | #1
On Wed, Dec 04, 2019 at 05:17:09PM +0900, Naohiro Aota wrote:
[..]

> +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
> +	char devstr[LEN];
> +	const int len = LEN;
> +#undef LEN

Why not:
	const int len = sizeof(device->fs_info->sb->s_id)
					+ sizeof("(device )") - 1;
	char devstr[len];

But that's bikeshedding territory I admit.

> +
> +	if (!bdev_is_zoned(bdev))
> +		return 0;
> +
> +	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
> +	if (!zone_info)
> +		return -ENOMEM;
> +
> +	zone_sectors = bdev_zone_sectors(bdev);
> +	ASSERT(is_power_of_2(zone_sectors));
> +	zone_info->zone_size = (u64)zone_sectors << SECTOR_SHIFT;
> +	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
> +	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
> +	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
> +		zone_info->nr_zones++;

You've already cached the return of bdev_zone_sectors(bdev) in
zone_sectors at the beginning of this block and if (x & (y-1)) is the
IS_ALIGNED() macro so the above should really be:
	if (!IS_ALIGNED(nr_sectors, zone_sectors))
		zone_info->nr_zones++;


> +
> +	zone_info->seq_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
> +				       sizeof(*zone_info->seq_zones),
> +				       GFP_KERNEL);

	zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);

> +	if (!zone_info->seq_zones) {
> +		ret = -ENOMEM;
> +		goto free_zone_info;
> +	}
> +
> +	zone_info->empty_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
> +					 sizeof(*zone_info->empty_zones),
> +					 GFP_KERNEL);
	
	zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);

> +	if (!zone_info->empty_zones) {
> +		ret = -ENOMEM;
> +		goto free_seq_zones;
> +	}
> +
> +	zones = kcalloc(BTRFS_REPORT_NR_ZONES,
> +			sizeof(struct blk_zone), GFP_KERNEL);
> +	if (!zones) {
> +		ret = -ENOMEM;
> +		goto free_empty_zones;
> +	}
> +

I personally would set nreported = 0 here instead in the declaration block. I
had to scroll up to see what's the initial value, so I think it makes more
sense to initialize it to 0 here.

> +	/* Get zones type */
> +	while (sector < nr_sectors) {
> +		nr_zones = BTRFS_REPORT_NR_ZONES;
> +		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
> +					  &nr_zones);
> +		if (ret)
> +			goto free_zones;
> +
> +		for (i = 0; i < nr_zones; i++) {
> +			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
> +				set_bit(nreported, zone_info->seq_zones);
> +			if (zones[i].cond == BLK_ZONE_COND_EMPTY)
> +				set_bit(nreported, zone_info->empty_zones);
> +			nreported++;
> +		}
> +		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
> +	}
> +
> +	if (nreported != zone_info->nr_zones) {
> +		btrfs_err_in_rcu(device->fs_info,
> +				 "inconsistent number of zones on %s (%u / %u)",
> +				 rcu_str_deref(device->name), nreported,
> +				 zone_info->nr_zones);
> +		ret = -EIO;
> +		goto free_zones;
> +	}
> +
> +	kfree(zones);
> +
> +	device->zone_info = zone_info;
> +
> +	devstr[0] = 0;
> +	if (device->fs_info)
> +		snprintf(devstr, len, " (device %s)",
> +			 device->fs_info->sb->s_id);
> +
> +	rcu_read_lock();
> +	pr_info(
> +"BTRFS info%s: host-%s zoned block device %s, %u zones of %llu sectors",
> +		devstr,
> +		bdev_zoned_model(bdev) == BLK_ZONED_HM ? "managed" : "aware",
> +		rcu_str_deref(device->name), zone_info->nr_zones,
> +		zone_info->zone_size >> SECTOR_SHIFT);
> +	rcu_read_unlock();

btrfs_info_in_rcu()?

> +
> +	return 0;
> +
> +free_zones:
> +	kfree(zones);
> +free_empty_zones:
> +	kfree(zone_info->empty_zones);
	
	bitmap_free(zone_info->empty_zones);

> +free_seq_zones:
> +	kfree(zone_info->seq_zones);
 	
	bitmap_free(zone_info->seq_zones);

> +free_zone_info:
> +	kfree(zone_info);
> +
> +	return ret;
> +}
> +
> +void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
> +{
> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
> +
> +	if (!zone_info)
> +		return;
> +
> +	kfree(zone_info->seq_zones);
> +	kfree(zone_info->empty_zones);

	bitmap_free(zone_info->seq_zones);
	bitmap_free(zone_info->empty_zones);

Thanks,
	Johannes
David Sterba Dec. 4, 2019, 5:22 p.m. UTC | #2
On Wed, Dec 04, 2019 at 04:37:32PM +0100, Johannes Thumshirn wrote:
> On Wed, Dec 04, 2019 at 05:17:09PM +0900, Naohiro Aota wrote:
> [..]
> 
> > +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
> > +	char devstr[LEN];
> > +	const int len = LEN;
> > +#undef LEN
> 
> Why not:
> 	const int len = sizeof(device->fs_info->sb->s_id)
> 					+ sizeof("(device )") - 1;
> 	char devstr[len];

len is used only once for snprintf to devstr, so there it can be
replaced by sizeof(devstr) and the sizeof()+sizeof() can be used for
devstr declaration.

The size of devstr seems to be one byte shorter than needed:

> > +		snprintf(devstr, len, " (device %s)",
> > +			 device->fs_info->sb->s_id);

There's a leading " " at the begining that I don't see accounted for.
Naohiro Aota Dec. 5, 2019, 6:28 a.m. UTC | #3
On Wed, Dec 04, 2019 at 04:37:32PM +0100, Johannes Thumshirn wrote:
>On Wed, Dec 04, 2019 at 05:17:09PM +0900, Naohiro Aota wrote:
>[..]
>
>> +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
>> +	char devstr[LEN];
>> +	const int len = LEN;
>> +#undef LEN
>
>Why not:
>	const int len = sizeof(device->fs_info->sb->s_id)
>					+ sizeof("(device )") - 1;
>	char devstr[len];
>
>But that's bikeshedding territory I admit.

I once tried that way, but it shows a "warning: ISO C90 forbids array
‘devstr’ whose size can’t be evaluated". So, I avoided that.

>
>> +
>> +	if (!bdev_is_zoned(bdev))
>> +		return 0;
>> +
>> +	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
>> +	if (!zone_info)
>> +		return -ENOMEM;
>> +
>> +	zone_sectors = bdev_zone_sectors(bdev);
>> +	ASSERT(is_power_of_2(zone_sectors));
>> +	zone_info->zone_size = (u64)zone_sectors << SECTOR_SHIFT;
>> +	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
>> +	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
>> +	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
>> +		zone_info->nr_zones++;
>
>You've already cached the return of bdev_zone_sectors(bdev) in
>zone_sectors at the beginning of this block and if (x & (y-1)) is the
>IS_ALIGNED() macro so the above should really be:
>	if (!IS_ALIGNED(nr_sectors, zone_sectors))
>		zone_info->nr_zones++;
>
>

Great. That's much clear.

>> +
>> +	zone_info->seq_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
>> +				       sizeof(*zone_info->seq_zones),
>> +				       GFP_KERNEL);
>
>	zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
>
>> +	if (!zone_info->seq_zones) {
>> +		ret = -ENOMEM;
>> +		goto free_zone_info;
>> +	}
>> +
>> +	zone_info->empty_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
>> +					 sizeof(*zone_info->empty_zones),
>> +					 GFP_KERNEL);
>	
>	zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
>

Thanks, I'll use the bitmap allocation helpers in the next version.

>> +	if (!zone_info->empty_zones) {
>> +		ret = -ENOMEM;
>> +		goto free_seq_zones;
>> +	}
>> +
>> +	zones = kcalloc(BTRFS_REPORT_NR_ZONES,
>> +			sizeof(struct blk_zone), GFP_KERNEL);
>> +	if (!zones) {
>> +		ret = -ENOMEM;
>> +		goto free_empty_zones;
>> +	}
>> +
>
>I personally would set nreported = 0 here instead in the declaration block. I
>had to scroll up to see what's the initial value, so I think it makes more
>sense to initialize it to 0 here.
>

OK, I'll do so.

>> +	/* Get zones type */
>> +	while (sector < nr_sectors) {
>> +		nr_zones = BTRFS_REPORT_NR_ZONES;
>> +		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
>> +					  &nr_zones);
>> +		if (ret)
>> +			goto free_zones;
>> +
>> +		for (i = 0; i < nr_zones; i++) {
>> +			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
>> +				set_bit(nreported, zone_info->seq_zones);
>> +			if (zones[i].cond == BLK_ZONE_COND_EMPTY)
>> +				set_bit(nreported, zone_info->empty_zones);
>> +			nreported++;
>> +		}
>> +		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
>> +	}
>> +
>> +	if (nreported != zone_info->nr_zones) {
>> +		btrfs_err_in_rcu(device->fs_info,
>> +				 "inconsistent number of zones on %s (%u / %u)",
>> +				 rcu_str_deref(device->name), nreported,
>> +				 zone_info->nr_zones);
>> +		ret = -EIO;
>> +		goto free_zones;
>> +	}
>> +
>> +	kfree(zones);
>> +
>> +	device->zone_info = zone_info;
>> +
>> +	devstr[0] = 0;
>> +	if (device->fs_info)
>> +		snprintf(devstr, len, " (device %s)",
>> +			 device->fs_info->sb->s_id);
>> +
>> +	rcu_read_lock();
>> +	pr_info(
>> +"BTRFS info%s: host-%s zoned block device %s, %u zones of %llu sectors",
>> +		devstr,
>> +		bdev_zoned_model(bdev) == BLK_ZONED_HM ? "managed" : "aware",
>> +		rcu_str_deref(device->name), zone_info->nr_zones,
>> +		zone_info->zone_size >> SECTOR_SHIFT);
>> +	rcu_read_unlock();
>
>btrfs_info_in_rcu()?
>

Since this function is called before btrfs set "fs_info->sb->s_id",
btrfs_info_in_rcu() prints like "BTRFS info (device <unknown>) ...", which
is annoying. I intentionally used pr_info() and rcu_read_{lock,unlock} here
to show a cleaner print.

>> +
>> +	return 0;
>> +
>> +free_zones:
>> +	kfree(zones);
>> +free_empty_zones:
>> +	kfree(zone_info->empty_zones);
>	
>	bitmap_free(zone_info->empty_zones);
>
>> +free_seq_zones:
>> +	kfree(zone_info->seq_zones);
> 	
>	bitmap_free(zone_info->seq_zones);
>
>> +free_zone_info:
>> +	kfree(zone_info);
>> +
>> +	return ret;
>> +}
>> +
>> +void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
>> +{
>> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
>> +
>> +	if (!zone_info)
>> +		return;
>> +
>> +	kfree(zone_info->seq_zones);
>> +	kfree(zone_info->empty_zones);
>
>	bitmap_free(zone_info->seq_zones);
>	bitmap_free(zone_info->empty_zones);
>
>Thanks,
>	Johannes
Naohiro Aota Dec. 5, 2019, 6:29 a.m. UTC | #4
On Wed, Dec 04, 2019 at 06:22:34PM +0100, David Sterba wrote:
>On Wed, Dec 04, 2019 at 04:37:32PM +0100, Johannes Thumshirn wrote:
>> On Wed, Dec 04, 2019 at 05:17:09PM +0900, Naohiro Aota wrote:
>> [..]
>>
>> > +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
>> > +	char devstr[LEN];
>> > +	const int len = LEN;
>> > +#undef LEN
>>
>> Why not:
>> 	const int len = sizeof(device->fs_info->sb->s_id)
>> 					+ sizeof("(device )") - 1;
>> 	char devstr[len];
>
>len is used only once for snprintf to devstr, so there it can be
>replaced by sizeof(devstr) and the sizeof()+sizeof() can be used for
>devstr declaration.
>

That's better. I'll fix in that way.

>The size of devstr seems to be one byte shorter than needed:
>
>> > +		snprintf(devstr, len, " (device %s)",
>> > +			 device->fs_info->sb->s_id);
>
>There's a leading " " at the begining that I don't see accounted for.

Oops, I'll fix. Thanks.
Anand Jain Dec. 7, 2019, 9:47 a.m. UTC | #5
On 4/12/19 4:17 PM, Naohiro Aota wrote:
> If a zoned block device is found, get its zone information (number of zones
> and zone size) using the new helper function btrfs_get_dev_zone_info().  To
> avoid costly run-time zone report commands to test the device zones type
> during block allocation, attach the seq_zones bitmap to the device
> structure to indicate if a zone is sequential or accept random writes. Also
> it attaches the empty_zones bitmap to indicate if a zone is empty or not.
> 
> This patch also introduces the helper function btrfs_dev_is_sequential() to
> test if the zone storing a block is a sequential write required zone and
> btrfs_dev_is_empty_zone() to test if the zone is a empty zone.
> 
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
> ---
>   fs/btrfs/Makefile  |   1 +
>   fs/btrfs/hmzoned.c | 174 +++++++++++++++++++++++++++++++++++++++++++++
>   fs/btrfs/hmzoned.h |  92 ++++++++++++++++++++++++
>   fs/btrfs/volumes.c |  18 ++++-
>   fs/btrfs/volumes.h |   4 ++
>   5 files changed, 287 insertions(+), 2 deletions(-)
>   create mode 100644 fs/btrfs/hmzoned.c
>   create mode 100644 fs/btrfs/hmzoned.h
> 
> diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
> index 82200dbca5ac..64aaeed397a4 100644
> --- a/fs/btrfs/Makefile
> +++ b/fs/btrfs/Makefile
> @@ -16,6 +16,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
>   btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
>   btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
>   btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
> +btrfs-$(CONFIG_BLK_DEV_ZONED) += hmzoned.o
>   
>   btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
>   	tests/extent-buffer-tests.o tests/btrfs-tests.o \
> diff --git a/fs/btrfs/hmzoned.c b/fs/btrfs/hmzoned.c
> new file mode 100644
> index 000000000000..e37335625f76
> --- /dev/null
> +++ b/fs/btrfs/hmzoned.c
> @@ -0,0 +1,174 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + * Authors:
> + *	Naohiro Aota	<naohiro.aota@wdc.com>
> + *	Damien Le Moal	<damien.lemoal@wdc.com>
> + */
> +
> +#include <linux/slab.h>
> +#include <linux/blkdev.h>
> +#include "ctree.h"
> +#include "volumes.h"
> +#include "hmzoned.h"
> +#include "rcu-string.h"
> +
> +/* Maximum number of zones to report per blkdev_report_zones() call */
> +#define BTRFS_REPORT_NR_ZONES   4096
> +
> +static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
> +			       struct blk_zone *zones, unsigned int *nr_zones)
> +{
> +	int ret;
> +
> +	ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, zones,
> +				  nr_zones);

  Commit d41003513e61 (block: rework zone reporting) has made into the
  mainline, which changes the definition of this function and fails to
  compile with the mainline.

Thanks, Anand



> +	if (ret != 0) {
> +		btrfs_err_in_rcu(device->fs_info,
> +				 "get zone at %llu on %s failed %d", pos,
> +				 rcu_str_deref(device->name), ret);
> +		return ret;
> +	}
> +	if (!*nr_zones)
> +		return -EIO;
> +
> +	return 0;
> +}
> +
> +int btrfs_get_dev_zone_info(struct btrfs_device *device)
> +{
> +	struct btrfs_zoned_device_info *zone_info = NULL;
> +	struct block_device *bdev = device->bdev;
> +	sector_t nr_sectors = bdev->bd_part->nr_sects;
> +	sector_t sector = 0;
> +	struct blk_zone *zones = NULL;
> +	unsigned int i, nreported = 0, nr_zones;
> +	unsigned int zone_sectors;
> +	int ret;
> +#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
> +	char devstr[LEN];
> +	const int len = LEN;
> +#undef LEN
> +
> +	if (!bdev_is_zoned(bdev))
> +		return 0;
> +
> +	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
> +	if (!zone_info)
> +		return -ENOMEM;
> +
> +	zone_sectors = bdev_zone_sectors(bdev);
> +	ASSERT(is_power_of_2(zone_sectors));
> +	zone_info->zone_size = (u64)zone_sectors << SECTOR_SHIFT;
> +	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
> +	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
> +	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
> +		zone_info->nr_zones++;
> +
> +	zone_info->seq_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
> +				       sizeof(*zone_info->seq_zones),
> +				       GFP_KERNEL);
> +	if (!zone_info->seq_zones) {
> +		ret = -ENOMEM;
> +		goto free_zone_info;
> +	}
> +
> +	zone_info->empty_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
> +					 sizeof(*zone_info->empty_zones),
> +					 GFP_KERNEL);
> +	if (!zone_info->empty_zones) {
> +		ret = -ENOMEM;
> +		goto free_seq_zones;
> +	}
> +
> +	zones = kcalloc(BTRFS_REPORT_NR_ZONES,
> +			sizeof(struct blk_zone), GFP_KERNEL);
> +	if (!zones) {
> +		ret = -ENOMEM;
> +		goto free_empty_zones;
> +	}
> +
> +	/* Get zones type */
> +	while (sector < nr_sectors) {
> +		nr_zones = BTRFS_REPORT_NR_ZONES;
> +		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
> +					  &nr_zones);
> +		if (ret)
> +			goto free_zones;
> +
> +		for (i = 0; i < nr_zones; i++) {
> +			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
> +				set_bit(nreported, zone_info->seq_zones);
> +			if (zones[i].cond == BLK_ZONE_COND_EMPTY)
> +				set_bit(nreported, zone_info->empty_zones);
> +			nreported++;
> +		}
> +		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
> +	}
> +
> +	if (nreported != zone_info->nr_zones) {
> +		btrfs_err_in_rcu(device->fs_info,
> +				 "inconsistent number of zones on %s (%u / %u)",
> +				 rcu_str_deref(device->name), nreported,
> +				 zone_info->nr_zones);
> +		ret = -EIO;
> +		goto free_zones;
> +	}
> +
> +	kfree(zones);
> +
> +	device->zone_info = zone_info;
> +
> +	devstr[0] = 0;
> +	if (device->fs_info)
> +		snprintf(devstr, len, " (device %s)",
> +			 device->fs_info->sb->s_id);
> +
> +	rcu_read_lock();
> +	pr_info(
> +"BTRFS info%s: host-%s zoned block device %s, %u zones of %llu sectors",
> +		devstr,
> +		bdev_zoned_model(bdev) == BLK_ZONED_HM ? "managed" : "aware",
> +		rcu_str_deref(device->name), zone_info->nr_zones,
> +		zone_info->zone_size >> SECTOR_SHIFT);
> +	rcu_read_unlock();
> +
> +	return 0;
> +
> +free_zones:
> +	kfree(zones);
> +free_empty_zones:
> +	kfree(zone_info->empty_zones);
> +free_seq_zones:
> +	kfree(zone_info->seq_zones);
> +free_zone_info:
> +	kfree(zone_info);
> +
> +	return ret;
> +}
> +
> +void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
> +{
> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
> +
> +	if (!zone_info)
> +		return;
> +
> +	kfree(zone_info->seq_zones);
> +	kfree(zone_info->empty_zones);
> +	kfree(zone_info);
> +	device->zone_info = NULL;
> +}
> +
> +int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
> +		       struct blk_zone *zone)
> +{
> +	unsigned int nr_zones = 1;
> +	int ret;
> +
> +	ret = btrfs_get_dev_zones(device, pos, zone, &nr_zones);
> +	if (ret != 0 || !nr_zones)
> +		return ret ? ret : -EIO;
> +
> +	return 0;
> +}
> diff --git a/fs/btrfs/hmzoned.h b/fs/btrfs/hmzoned.h
> new file mode 100644
> index 000000000000..0f8006f39aaf
> --- /dev/null
> +++ b/fs/btrfs/hmzoned.h
> @@ -0,0 +1,92 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + * Authors:
> + *	Naohiro Aota	<naohiro.aota@wdc.com>
> + *	Damien Le Moal	<damien.lemoal@wdc.com>
> + */
> +
> +#ifndef BTRFS_HMZONED_H
> +#define BTRFS_HMZONED_H
> +
> +struct btrfs_zoned_device_info {
> +	/*
> +	 * Number of zones, zone size and types of zones if bdev is a
> +	 * zoned block device.
> +	 */
> +	u64 zone_size;
> +	u8  zone_size_shift;
> +	u32 nr_zones;
> +	unsigned long *seq_zones;
> +	unsigned long *empty_zones;
> +};
> +
> +#ifdef CONFIG_BLK_DEV_ZONED
> +int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
> +		       struct blk_zone *zone);
> +int btrfs_get_dev_zone_info(struct btrfs_device *device);
> +void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
> +#else /* CONFIG_BLK_DEV_ZONED */
> +static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
> +				     struct blk_zone *zone)
> +{
> +	return 0;
> +}
> +static inline int btrfs_get_dev_zone_info(struct btrfs_device *device)
> +{
> +	return 0;
> +}
> +static inline void btrfs_destroy_dev_zone_info(struct btrfs_device *device) { }
> +#endif
> +
> +static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
> +{
> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
> +
> +	if (!zone_info)
> +		return false;
> +
> +	return test_bit(pos >> zone_info->zone_size_shift,
> +			zone_info->seq_zones);
> +}
> +
> +static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
> +{
> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
> +
> +	if (!zone_info)
> +		return true;
> +
> +	return test_bit(pos >> zone_info->zone_size_shift,
> +			zone_info->empty_zones);
> +}
> +
> +static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
> +						u64 pos, bool set)
> +{
> +	struct btrfs_zoned_device_info *zone_info = device->zone_info;
> +	unsigned int zno;
> +
> +	if (!zone_info)
> +		return;
> +
> +	zno = pos >> zone_info->zone_size_shift;
> +	if (set)
> +		set_bit(zno, zone_info->empty_zones);
> +	else
> +		clear_bit(zno, zone_info->empty_zones);
> +}
> +
> +static inline void btrfs_dev_set_zone_empty(struct btrfs_device *device,
> +					    u64 pos)
> +{
> +	btrfs_dev_set_empty_zone_bit(device, pos, true);
> +}
> +
> +static inline void btrfs_dev_clear_zone_empty(struct btrfs_device *device,
> +					      u64 pos)
> +{
> +	btrfs_dev_set_empty_zone_bit(device, pos, false);
> +}
> +
> +#endif
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index d8e5560db285..18ea8dfce244 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -30,6 +30,7 @@
>   #include "tree-checker.h"
>   #include "space-info.h"
>   #include "block-group.h"
> +#include "hmzoned.h"
>   
>   const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
>   	[BTRFS_RAID_RAID10] = {
> @@ -366,6 +367,7 @@ void btrfs_free_device(struct btrfs_device *device)
>   	rcu_string_free(device->name);
>   	extent_io_tree_release(&device->alloc_state);
>   	bio_put(device->flush_bio);
> +	btrfs_destroy_dev_zone_info(device);
>   	kfree(device);
>   }
>   
> @@ -650,6 +652,11 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
>   	clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
>   	device->mode = flags;
>   
> +	/* Get zone type information of zoned block devices */
> +	ret = btrfs_get_dev_zone_info(device);
> +	if (ret != 0)
> +		goto error_brelse;
> +
>   	fs_devices->open_devices++;
>   	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
>   	    device->devid != BTRFS_DEV_REPLACE_DEVID) {
> @@ -2421,6 +2428,14 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>   	}
>   	rcu_assign_pointer(device->name, name);
>   
> +	device->fs_info = fs_info;
> +	device->bdev = bdev;
> +
> +	/* Get zone type information of zoned block devices */
> +	ret = btrfs_get_dev_zone_info(device);
> +	if (ret)
> +		goto error_free_device;
> +
>   	trans = btrfs_start_transaction(root, 0);
>   	if (IS_ERR(trans)) {
>   		ret = PTR_ERR(trans);
> @@ -2437,8 +2452,6 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>   					 fs_info->sectorsize);
>   	device->disk_total_bytes = device->total_bytes;
>   	device->commit_total_bytes = device->total_bytes;
> -	device->fs_info = fs_info;
> -	device->bdev = bdev;
>   	set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
>   	clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
>   	device->mode = FMODE_EXCL;
> @@ -2571,6 +2584,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>   		sb->s_flags |= SB_RDONLY;
>   	if (trans)
>   		btrfs_end_transaction(trans);
> +	btrfs_destroy_dev_zone_info(device);
>   error_free_device:
>   	btrfs_free_device(device);
>   error:
> diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
> index fc1b564b9cfe..70cabe65f72a 100644
> --- a/fs/btrfs/volumes.h
> +++ b/fs/btrfs/volumes.h
> @@ -53,6 +53,8 @@ struct btrfs_io_geometry {
>   #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
>   #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
>   
> +struct btrfs_zoned_device_info;
> +
>   struct btrfs_device {
>   	struct list_head dev_list; /* device_list_mutex */
>   	struct list_head dev_alloc_list; /* chunk mutex */
> @@ -66,6 +68,8 @@ struct btrfs_device {
>   
>   	struct block_device *bdev;
>   
> +	struct btrfs_zoned_device_info *zone_info;
> +
>   	/* the mode sent to blkdev_get */
>   	fmode_t mode;
>   
>
Naohiro Aota Dec. 10, 2019, 4:41 a.m. UTC | #6
On Sat, Dec 07, 2019 at 05:47:35PM +0800, Anand Jain wrote:
>On 4/12/19 4:17 PM, Naohiro Aota wrote:
>>If a zoned block device is found, get its zone information (number of zones
>>and zone size) using the new helper function btrfs_get_dev_zone_info().  To
>>avoid costly run-time zone report commands to test the device zones type
>>during block allocation, attach the seq_zones bitmap to the device
>>structure to indicate if a zone is sequential or accept random writes. Also
>>it attaches the empty_zones bitmap to indicate if a zone is empty or not.
>>
>>This patch also introduces the helper function btrfs_dev_is_sequential() to
>>test if the zone storing a block is a sequential write required zone and
>>btrfs_dev_is_empty_zone() to test if the zone is a empty zone.
>>
>>Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
>>Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
>>---
>>  fs/btrfs/Makefile  |   1 +
>>  fs/btrfs/hmzoned.c | 174 +++++++++++++++++++++++++++++++++++++++++++++
>>  fs/btrfs/hmzoned.h |  92 ++++++++++++++++++++++++
>>  fs/btrfs/volumes.c |  18 ++++-
>>  fs/btrfs/volumes.h |   4 ++
>>  5 files changed, 287 insertions(+), 2 deletions(-)
>>  create mode 100644 fs/btrfs/hmzoned.c
>>  create mode 100644 fs/btrfs/hmzoned.h
>>
>>diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
>>index 82200dbca5ac..64aaeed397a4 100644
>>--- a/fs/btrfs/Makefile
>>+++ b/fs/btrfs/Makefile
>>@@ -16,6 +16,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
>>  btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
>>  btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
>>  btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
>>+btrfs-$(CONFIG_BLK_DEV_ZONED) += hmzoned.o
>>  btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
>>  	tests/extent-buffer-tests.o tests/btrfs-tests.o \
>>diff --git a/fs/btrfs/hmzoned.c b/fs/btrfs/hmzoned.c
>>new file mode 100644
>>index 000000000000..e37335625f76
>>--- /dev/null
>>+++ b/fs/btrfs/hmzoned.c
>>@@ -0,0 +1,174 @@
>>+// SPDX-License-Identifier: GPL-2.0
>>+/*
>>+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
>>+ * Authors:
>>+ *	Naohiro Aota	<naohiro.aota@wdc.com>
>>+ *	Damien Le Moal	<damien.lemoal@wdc.com>
>>+ */
>>+
>>+#include <linux/slab.h>
>>+#include <linux/blkdev.h>
>>+#include "ctree.h"
>>+#include "volumes.h"
>>+#include "hmzoned.h"
>>+#include "rcu-string.h"
>>+
>>+/* Maximum number of zones to report per blkdev_report_zones() call */
>>+#define BTRFS_REPORT_NR_ZONES   4096
>>+
>>+static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
>>+			       struct blk_zone *zones, unsigned int *nr_zones)
>>+{
>>+	int ret;
>>+
>>+	ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, zones,
>>+				  nr_zones);
>
> Commit d41003513e61 (block: rework zone reporting) has made into the
> mainline, which changes the definition of this function and fails to
> compile with the mainline.

Yes, I'm aware of the blk-zoned API change. This patch series is based
on kdave/for-5.5 which is basing on v5.4-rc8, thus the basing branch
does not contain the block layer commits yet. I will add a patch to
follow the API change in the next version of my patch series.

Thanks,

>Thanks, Anand
>
>
>
>>+	if (ret != 0) {
>>+		btrfs_err_in_rcu(device->fs_info,
>>+				 "get zone at %llu on %s failed %d", pos,
>>+				 rcu_str_deref(device->name), ret);
>>+		return ret;
>>+	}
>>+	if (!*nr_zones)
>>+		return -EIO;
>>+
>>+	return 0;
>>+}
>>+
>>+int btrfs_get_dev_zone_info(struct btrfs_device *device)
>>+{
>>+	struct btrfs_zoned_device_info *zone_info = NULL;
>>+	struct block_device *bdev = device->bdev;
>>+	sector_t nr_sectors = bdev->bd_part->nr_sects;
>>+	sector_t sector = 0;
>>+	struct blk_zone *zones = NULL;
>>+	unsigned int i, nreported = 0, nr_zones;
>>+	unsigned int zone_sectors;
>>+	int ret;
>>+#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
>>+	char devstr[LEN];
>>+	const int len = LEN;
>>+#undef LEN
>>+
>>+	if (!bdev_is_zoned(bdev))
>>+		return 0;
>>+
>>+	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
>>+	if (!zone_info)
>>+		return -ENOMEM;
>>+
>>+	zone_sectors = bdev_zone_sectors(bdev);
>>+	ASSERT(is_power_of_2(zone_sectors));
>>+	zone_info->zone_size = (u64)zone_sectors << SECTOR_SHIFT;
>>+	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
>>+	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
>>+	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
>>+		zone_info->nr_zones++;
>>+
>>+	zone_info->seq_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
>>+				       sizeof(*zone_info->seq_zones),
>>+				       GFP_KERNEL);
>>+	if (!zone_info->seq_zones) {
>>+		ret = -ENOMEM;
>>+		goto free_zone_info;
>>+	}
>>+
>>+	zone_info->empty_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
>>+					 sizeof(*zone_info->empty_zones),
>>+					 GFP_KERNEL);
>>+	if (!zone_info->empty_zones) {
>>+		ret = -ENOMEM;
>>+		goto free_seq_zones;
>>+	}
>>+
>>+	zones = kcalloc(BTRFS_REPORT_NR_ZONES,
>>+			sizeof(struct blk_zone), GFP_KERNEL);
>>+	if (!zones) {
>>+		ret = -ENOMEM;
>>+		goto free_empty_zones;
>>+	}
>>+
>>+	/* Get zones type */
>>+	while (sector < nr_sectors) {
>>+		nr_zones = BTRFS_REPORT_NR_ZONES;
>>+		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
>>+					  &nr_zones);
>>+		if (ret)
>>+			goto free_zones;
>>+
>>+		for (i = 0; i < nr_zones; i++) {
>>+			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
>>+				set_bit(nreported, zone_info->seq_zones);
>>+			if (zones[i].cond == BLK_ZONE_COND_EMPTY)
>>+				set_bit(nreported, zone_info->empty_zones);
>>+			nreported++;
>>+		}
>>+		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
>>+	}
>>+
>>+	if (nreported != zone_info->nr_zones) {
>>+		btrfs_err_in_rcu(device->fs_info,
>>+				 "inconsistent number of zones on %s (%u / %u)",
>>+				 rcu_str_deref(device->name), nreported,
>>+				 zone_info->nr_zones);
>>+		ret = -EIO;
>>+		goto free_zones;
>>+	}
>>+
>>+	kfree(zones);
>>+
>>+	device->zone_info = zone_info;
>>+
>>+	devstr[0] = 0;
>>+	if (device->fs_info)
>>+		snprintf(devstr, len, " (device %s)",
>>+			 device->fs_info->sb->s_id);
>>+
>>+	rcu_read_lock();
>>+	pr_info(
>>+"BTRFS info%s: host-%s zoned block device %s, %u zones of %llu sectors",
>>+		devstr,
>>+		bdev_zoned_model(bdev) == BLK_ZONED_HM ? "managed" : "aware",
>>+		rcu_str_deref(device->name), zone_info->nr_zones,
>>+		zone_info->zone_size >> SECTOR_SHIFT);
>>+	rcu_read_unlock();
>>+
>>+	return 0;
>>+
>>+free_zones:
>>+	kfree(zones);
>>+free_empty_zones:
>>+	kfree(zone_info->empty_zones);
>>+free_seq_zones:
>>+	kfree(zone_info->seq_zones);
>>+free_zone_info:
>>+	kfree(zone_info);
>>+
>>+	return ret;
>>+}
>>+
>>+void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
>>+{
>>+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
>>+
>>+	if (!zone_info)
>>+		return;
>>+
>>+	kfree(zone_info->seq_zones);
>>+	kfree(zone_info->empty_zones);
>>+	kfree(zone_info);
>>+	device->zone_info = NULL;
>>+}
>>+
>>+int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
>>+		       struct blk_zone *zone)
>>+{
>>+	unsigned int nr_zones = 1;
>>+	int ret;
>>+
>>+	ret = btrfs_get_dev_zones(device, pos, zone, &nr_zones);
>>+	if (ret != 0 || !nr_zones)
>>+		return ret ? ret : -EIO;
>>+
>>+	return 0;
>>+}
>>diff --git a/fs/btrfs/hmzoned.h b/fs/btrfs/hmzoned.h
>>new file mode 100644
>>index 000000000000..0f8006f39aaf
>>--- /dev/null
>>+++ b/fs/btrfs/hmzoned.h
>>@@ -0,0 +1,92 @@
>>+/* SPDX-License-Identifier: GPL-2.0 */
>>+/*
>>+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
>>+ * Authors:
>>+ *	Naohiro Aota	<naohiro.aota@wdc.com>
>>+ *	Damien Le Moal	<damien.lemoal@wdc.com>
>>+ */
>>+
>>+#ifndef BTRFS_HMZONED_H
>>+#define BTRFS_HMZONED_H
>>+
>>+struct btrfs_zoned_device_info {
>>+	/*
>>+	 * Number of zones, zone size and types of zones if bdev is a
>>+	 * zoned block device.
>>+	 */
>>+	u64 zone_size;
>>+	u8  zone_size_shift;
>>+	u32 nr_zones;
>>+	unsigned long *seq_zones;
>>+	unsigned long *empty_zones;
>>+};
>>+
>>+#ifdef CONFIG_BLK_DEV_ZONED
>>+int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
>>+		       struct blk_zone *zone);
>>+int btrfs_get_dev_zone_info(struct btrfs_device *device);
>>+void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
>>+#else /* CONFIG_BLK_DEV_ZONED */
>>+static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
>>+				     struct blk_zone *zone)
>>+{
>>+	return 0;
>>+}
>>+static inline int btrfs_get_dev_zone_info(struct btrfs_device *device)
>>+{
>>+	return 0;
>>+}
>>+static inline void btrfs_destroy_dev_zone_info(struct btrfs_device *device) { }
>>+#endif
>>+
>>+static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
>>+{
>>+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
>>+
>>+	if (!zone_info)
>>+		return false;
>>+
>>+	return test_bit(pos >> zone_info->zone_size_shift,
>>+			zone_info->seq_zones);
>>+}
>>+
>>+static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
>>+{
>>+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
>>+
>>+	if (!zone_info)
>>+		return true;
>>+
>>+	return test_bit(pos >> zone_info->zone_size_shift,
>>+			zone_info->empty_zones);
>>+}
>>+
>>+static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
>>+						u64 pos, bool set)
>>+{
>>+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
>>+	unsigned int zno;
>>+
>>+	if (!zone_info)
>>+		return;
>>+
>>+	zno = pos >> zone_info->zone_size_shift;
>>+	if (set)
>>+		set_bit(zno, zone_info->empty_zones);
>>+	else
>>+		clear_bit(zno, zone_info->empty_zones);
>>+}
>>+
>>+static inline void btrfs_dev_set_zone_empty(struct btrfs_device *device,
>>+					    u64 pos)
>>+{
>>+	btrfs_dev_set_empty_zone_bit(device, pos, true);
>>+}
>>+
>>+static inline void btrfs_dev_clear_zone_empty(struct btrfs_device *device,
>>+					      u64 pos)
>>+{
>>+	btrfs_dev_set_empty_zone_bit(device, pos, false);
>>+}
>>+
>>+#endif
>>diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
>>index d8e5560db285..18ea8dfce244 100644
>>--- a/fs/btrfs/volumes.c
>>+++ b/fs/btrfs/volumes.c
>>@@ -30,6 +30,7 @@
>>  #include "tree-checker.h"
>>  #include "space-info.h"
>>  #include "block-group.h"
>>+#include "hmzoned.h"
>>  const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
>>  	[BTRFS_RAID_RAID10] = {
>>@@ -366,6 +367,7 @@ void btrfs_free_device(struct btrfs_device *device)
>>  	rcu_string_free(device->name);
>>  	extent_io_tree_release(&device->alloc_state);
>>  	bio_put(device->flush_bio);
>>+	btrfs_destroy_dev_zone_info(device);
>>  	kfree(device);
>>  }
>>@@ -650,6 +652,11 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
>>  	clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
>>  	device->mode = flags;
>>+	/* Get zone type information of zoned block devices */
>>+	ret = btrfs_get_dev_zone_info(device);
>>+	if (ret != 0)
>>+		goto error_brelse;
>>+
>>  	fs_devices->open_devices++;
>>  	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
>>  	    device->devid != BTRFS_DEV_REPLACE_DEVID) {
>>@@ -2421,6 +2428,14 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>>  	}
>>  	rcu_assign_pointer(device->name, name);
>>+	device->fs_info = fs_info;
>>+	device->bdev = bdev;
>>+
>>+	/* Get zone type information of zoned block devices */
>>+	ret = btrfs_get_dev_zone_info(device);
>>+	if (ret)
>>+		goto error_free_device;
>>+
>>  	trans = btrfs_start_transaction(root, 0);
>>  	if (IS_ERR(trans)) {
>>  		ret = PTR_ERR(trans);
>>@@ -2437,8 +2452,6 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>>  					 fs_info->sectorsize);
>>  	device->disk_total_bytes = device->total_bytes;
>>  	device->commit_total_bytes = device->total_bytes;
>>-	device->fs_info = fs_info;
>>-	device->bdev = bdev;
>>  	set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
>>  	clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
>>  	device->mode = FMODE_EXCL;
>>@@ -2571,6 +2584,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>>  		sb->s_flags |= SB_RDONLY;
>>  	if (trans)
>>  		btrfs_end_transaction(trans);
>>+	btrfs_destroy_dev_zone_info(device);
>>  error_free_device:
>>  	btrfs_free_device(device);
>>  error:
>>diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
>>index fc1b564b9cfe..70cabe65f72a 100644
>>--- a/fs/btrfs/volumes.h
>>+++ b/fs/btrfs/volumes.h
>>@@ -53,6 +53,8 @@ struct btrfs_io_geometry {
>>  #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
>>  #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
>>+struct btrfs_zoned_device_info;
>>+
>>  struct btrfs_device {
>>  	struct list_head dev_list; /* device_list_mutex */
>>  	struct list_head dev_alloc_list; /* chunk mutex */
>>@@ -66,6 +68,8 @@ struct btrfs_device {
>>  	struct block_device *bdev;
>>+	struct btrfs_zoned_device_info *zone_info;
>>+
>>  	/* the mode sent to blkdev_get */
>>  	fmode_t mode;
>>
>

Patch
diff mbox series

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 82200dbca5ac..64aaeed397a4 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -16,6 +16,7 @@  btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
 btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
 btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
 btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
+btrfs-$(CONFIG_BLK_DEV_ZONED) += hmzoned.o
 
 btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
 	tests/extent-buffer-tests.o tests/btrfs-tests.o \
diff --git a/fs/btrfs/hmzoned.c b/fs/btrfs/hmzoned.c
new file mode 100644
index 000000000000..e37335625f76
--- /dev/null
+++ b/fs/btrfs/hmzoned.c
@@ -0,0 +1,174 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ * Authors:
+ *	Naohiro Aota	<naohiro.aota@wdc.com>
+ *	Damien Le Moal	<damien.lemoal@wdc.com>
+ */
+
+#include <linux/slab.h>
+#include <linux/blkdev.h>
+#include "ctree.h"
+#include "volumes.h"
+#include "hmzoned.h"
+#include "rcu-string.h"
+
+/* Maximum number of zones to report per blkdev_report_zones() call */
+#define BTRFS_REPORT_NR_ZONES   4096
+
+static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
+			       struct blk_zone *zones, unsigned int *nr_zones)
+{
+	int ret;
+
+	ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, zones,
+				  nr_zones);
+	if (ret != 0) {
+		btrfs_err_in_rcu(device->fs_info,
+				 "get zone at %llu on %s failed %d", pos,
+				 rcu_str_deref(device->name), ret);
+		return ret;
+	}
+	if (!*nr_zones)
+		return -EIO;
+
+	return 0;
+}
+
+int btrfs_get_dev_zone_info(struct btrfs_device *device)
+{
+	struct btrfs_zoned_device_info *zone_info = NULL;
+	struct block_device *bdev = device->bdev;
+	sector_t nr_sectors = bdev->bd_part->nr_sects;
+	sector_t sector = 0;
+	struct blk_zone *zones = NULL;
+	unsigned int i, nreported = 0, nr_zones;
+	unsigned int zone_sectors;
+	int ret;
+#define LEN (sizeof(device->fs_info->sb->s_id) + sizeof("(device )") - 1)
+	char devstr[LEN];
+	const int len = LEN;
+#undef LEN
+
+	if (!bdev_is_zoned(bdev))
+		return 0;
+
+	zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
+	if (!zone_info)
+		return -ENOMEM;
+
+	zone_sectors = bdev_zone_sectors(bdev);
+	ASSERT(is_power_of_2(zone_sectors));
+	zone_info->zone_size = (u64)zone_sectors << SECTOR_SHIFT;
+	zone_info->zone_size_shift = ilog2(zone_info->zone_size);
+	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
+	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
+		zone_info->nr_zones++;
+
+	zone_info->seq_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
+				       sizeof(*zone_info->seq_zones),
+				       GFP_KERNEL);
+	if (!zone_info->seq_zones) {
+		ret = -ENOMEM;
+		goto free_zone_info;
+	}
+
+	zone_info->empty_zones = kcalloc(BITS_TO_LONGS(zone_info->nr_zones),
+					 sizeof(*zone_info->empty_zones),
+					 GFP_KERNEL);
+	if (!zone_info->empty_zones) {
+		ret = -ENOMEM;
+		goto free_seq_zones;
+	}
+
+	zones = kcalloc(BTRFS_REPORT_NR_ZONES,
+			sizeof(struct blk_zone), GFP_KERNEL);
+	if (!zones) {
+		ret = -ENOMEM;
+		goto free_empty_zones;
+	}
+
+	/* Get zones type */
+	while (sector < nr_sectors) {
+		nr_zones = BTRFS_REPORT_NR_ZONES;
+		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
+					  &nr_zones);
+		if (ret)
+			goto free_zones;
+
+		for (i = 0; i < nr_zones; i++) {
+			if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
+				set_bit(nreported, zone_info->seq_zones);
+			if (zones[i].cond == BLK_ZONE_COND_EMPTY)
+				set_bit(nreported, zone_info->empty_zones);
+			nreported++;
+		}
+		sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
+	}
+
+	if (nreported != zone_info->nr_zones) {
+		btrfs_err_in_rcu(device->fs_info,
+				 "inconsistent number of zones on %s (%u / %u)",
+				 rcu_str_deref(device->name), nreported,
+				 zone_info->nr_zones);
+		ret = -EIO;
+		goto free_zones;
+	}
+
+	kfree(zones);
+
+	device->zone_info = zone_info;
+
+	devstr[0] = 0;
+	if (device->fs_info)
+		snprintf(devstr, len, " (device %s)",
+			 device->fs_info->sb->s_id);
+
+	rcu_read_lock();
+	pr_info(
+"BTRFS info%s: host-%s zoned block device %s, %u zones of %llu sectors",
+		devstr,
+		bdev_zoned_model(bdev) == BLK_ZONED_HM ? "managed" : "aware",
+		rcu_str_deref(device->name), zone_info->nr_zones,
+		zone_info->zone_size >> SECTOR_SHIFT);
+	rcu_read_unlock();
+
+	return 0;
+
+free_zones:
+	kfree(zones);
+free_empty_zones:
+	kfree(zone_info->empty_zones);
+free_seq_zones:
+	kfree(zone_info->seq_zones);
+free_zone_info:
+	kfree(zone_info);
+
+	return ret;
+}
+
+void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
+{
+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
+
+	if (!zone_info)
+		return;
+
+	kfree(zone_info->seq_zones);
+	kfree(zone_info->empty_zones);
+	kfree(zone_info);
+	device->zone_info = NULL;
+}
+
+int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
+		       struct blk_zone *zone)
+{
+	unsigned int nr_zones = 1;
+	int ret;
+
+	ret = btrfs_get_dev_zones(device, pos, zone, &nr_zones);
+	if (ret != 0 || !nr_zones)
+		return ret ? ret : -EIO;
+
+	return 0;
+}
diff --git a/fs/btrfs/hmzoned.h b/fs/btrfs/hmzoned.h
new file mode 100644
index 000000000000..0f8006f39aaf
--- /dev/null
+++ b/fs/btrfs/hmzoned.h
@@ -0,0 +1,92 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ * Authors:
+ *	Naohiro Aota	<naohiro.aota@wdc.com>
+ *	Damien Le Moal	<damien.lemoal@wdc.com>
+ */
+
+#ifndef BTRFS_HMZONED_H
+#define BTRFS_HMZONED_H
+
+struct btrfs_zoned_device_info {
+	/*
+	 * Number of zones, zone size and types of zones if bdev is a
+	 * zoned block device.
+	 */
+	u64 zone_size;
+	u8  zone_size_shift;
+	u32 nr_zones;
+	unsigned long *seq_zones;
+	unsigned long *empty_zones;
+};
+
+#ifdef CONFIG_BLK_DEV_ZONED
+int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
+		       struct blk_zone *zone);
+int btrfs_get_dev_zone_info(struct btrfs_device *device);
+void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
+#else /* CONFIG_BLK_DEV_ZONED */
+static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
+				     struct blk_zone *zone)
+{
+	return 0;
+}
+static inline int btrfs_get_dev_zone_info(struct btrfs_device *device)
+{
+	return 0;
+}
+static inline void btrfs_destroy_dev_zone_info(struct btrfs_device *device) { }
+#endif
+
+static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
+{
+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
+
+	if (!zone_info)
+		return false;
+
+	return test_bit(pos >> zone_info->zone_size_shift,
+			zone_info->seq_zones);
+}
+
+static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
+{
+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
+
+	if (!zone_info)
+		return true;
+
+	return test_bit(pos >> zone_info->zone_size_shift,
+			zone_info->empty_zones);
+}
+
+static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
+						u64 pos, bool set)
+{
+	struct btrfs_zoned_device_info *zone_info = device->zone_info;
+	unsigned int zno;
+
+	if (!zone_info)
+		return;
+
+	zno = pos >> zone_info->zone_size_shift;
+	if (set)
+		set_bit(zno, zone_info->empty_zones);
+	else
+		clear_bit(zno, zone_info->empty_zones);
+}
+
+static inline void btrfs_dev_set_zone_empty(struct btrfs_device *device,
+					    u64 pos)
+{
+	btrfs_dev_set_empty_zone_bit(device, pos, true);
+}
+
+static inline void btrfs_dev_clear_zone_empty(struct btrfs_device *device,
+					      u64 pos)
+{
+	btrfs_dev_set_empty_zone_bit(device, pos, false);
+}
+
+#endif
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d8e5560db285..18ea8dfce244 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -30,6 +30,7 @@ 
 #include "tree-checker.h"
 #include "space-info.h"
 #include "block-group.h"
+#include "hmzoned.h"
 
 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
 	[BTRFS_RAID_RAID10] = {
@@ -366,6 +367,7 @@  void btrfs_free_device(struct btrfs_device *device)
 	rcu_string_free(device->name);
 	extent_io_tree_release(&device->alloc_state);
 	bio_put(device->flush_bio);
+	btrfs_destroy_dev_zone_info(device);
 	kfree(device);
 }
 
@@ -650,6 +652,11 @@  static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 	clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
 	device->mode = flags;
 
+	/* Get zone type information of zoned block devices */
+	ret = btrfs_get_dev_zone_info(device);
+	if (ret != 0)
+		goto error_brelse;
+
 	fs_devices->open_devices++;
 	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
 	    device->devid != BTRFS_DEV_REPLACE_DEVID) {
@@ -2421,6 +2428,14 @@  int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	}
 	rcu_assign_pointer(device->name, name);
 
+	device->fs_info = fs_info;
+	device->bdev = bdev;
+
+	/* Get zone type information of zoned block devices */
+	ret = btrfs_get_dev_zone_info(device);
+	if (ret)
+		goto error_free_device;
+
 	trans = btrfs_start_transaction(root, 0);
 	if (IS_ERR(trans)) {
 		ret = PTR_ERR(trans);
@@ -2437,8 +2452,6 @@  int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 					 fs_info->sectorsize);
 	device->disk_total_bytes = device->total_bytes;
 	device->commit_total_bytes = device->total_bytes;
-	device->fs_info = fs_info;
-	device->bdev = bdev;
 	set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
 	clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
 	device->mode = FMODE_EXCL;
@@ -2571,6 +2584,7 @@  int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 		sb->s_flags |= SB_RDONLY;
 	if (trans)
 		btrfs_end_transaction(trans);
+	btrfs_destroy_dev_zone_info(device);
 error_free_device:
 	btrfs_free_device(device);
 error:
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index fc1b564b9cfe..70cabe65f72a 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -53,6 +53,8 @@  struct btrfs_io_geometry {
 #define BTRFS_DEV_STATE_REPLACE_TGT	(3)
 #define BTRFS_DEV_STATE_FLUSH_SENT	(4)
 
+struct btrfs_zoned_device_info;
+
 struct btrfs_device {
 	struct list_head dev_list; /* device_list_mutex */
 	struct list_head dev_alloc_list; /* chunk mutex */
@@ -66,6 +68,8 @@  struct btrfs_device {
 
 	struct block_device *bdev;
 
+	struct btrfs_zoned_device_info *zone_info;
+
 	/* the mode sent to blkdev_get */
 	fmode_t mode;