From: Naohiro Aota <naohiro.aota@wdc.com>
To: linux-btrfs@vger.kernel.org, dsterba@suse.com
Cc: hare@suse.com, linux-fsdevel@vger.kernel.org,
Naohiro Aota <naohiro.aota@wdc.com>,
Josef Bacik <josef@toxicpanda.com>,
Damien Le Moal <damien.lemoal@wdc.com>
Subject: [PATCH v8 03/41] btrfs: Get zone information of zoned block devices
Date: Fri, 2 Oct 2020 03:36:10 +0900 [thread overview]
Message-ID: <dd872ec3ab449a3a97c7a3843aafe15b10154a3f.1601574234.git.naohiro.aota@wdc.com> (raw)
In-Reply-To: <dece91bca322ce44bed19f2b0f460fa5ded2e512.1601574234.git.naohiro.aota@wdc.com>
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.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
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/dev-replace.c | 5 ++
fs/btrfs/volumes.c | 18 ++++-
fs/btrfs/volumes.h | 4 +
fs/btrfs/zoned.c | 179 +++++++++++++++++++++++++++++++++++++++++
fs/btrfs/zoned.h | 92 +++++++++++++++++++++
6 files changed, 297 insertions(+), 2 deletions(-)
create mode 100644 fs/btrfs/zoned.c
create mode 100644 fs/btrfs/zoned.h
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index e738f6206ea5..0497fdc37f90 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) += zoned.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/dev-replace.c b/fs/btrfs/dev-replace.c
index 20ce1970015f..6f6d77224c2b 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -21,6 +21,7 @@
#include "rcu-string.h"
#include "dev-replace.h"
#include "sysfs.h"
+#include "zoned.h"
/*
* Device replace overview
@@ -291,6 +292,10 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
device->fs_devices = fs_info->fs_devices;
+ ret = btrfs_get_dev_zone_info(device);
+ if (ret)
+ goto error;
+
mutex_lock(&fs_info->fs_devices->device_list_mutex);
list_add(&device->dev_list, &fs_info->fs_devices->devices);
fs_info->fs_devices->num_devices++;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 58b9c419a2b6..b0a7a820222e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -31,6 +31,7 @@
#include "space-info.h"
#include "block-group.h"
#include "discard.h"
+#include "zoned.h"
const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
[BTRFS_RAID_RAID10] = {
@@ -374,6 +375,7 @@ 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);
}
@@ -667,6 +669,11 @@ 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_free_page;
+
fs_devices->open_devices++;
if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
device->devid != BTRFS_DEV_REPLACE_DEVID) {
@@ -2543,6 +2550,14 @@ 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);
@@ -2559,8 +2574,6 @@ 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;
@@ -2707,6 +2720,7 @@ 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 48bdca01e237..4bbb15c4161f 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -51,6 +51,8 @@ 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 */
@@ -64,6 +66,8 @@ struct btrfs_device {
struct block_device *bdev;
+ struct btrfs_zoned_device_info *zone_info;
+
/* the mode sent to blkdev_get */
fmode_t mode;
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
new file mode 100644
index 000000000000..0c908f0e9469
--- /dev/null
+++ b/fs/btrfs/zoned.c
@@ -0,0 +1,179 @@
+// 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 "zoned.h"
+#include "rcu-string.h"
+
+/* Maximum number of zones to report per blkdev_report_zones() call */
+#define BTRFS_REPORT_NR_ZONES 4096
+
+static int copy_zone_info_cb(struct blk_zone *zone, unsigned int idx,
+ void *data)
+{
+ struct blk_zone *zones = data;
+
+ memcpy(&zones[idx], zone, sizeof(*zone));
+
+ return 0;
+}
+
+static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
+ struct blk_zone *zones, unsigned int *nr_zones)
+{
+ int ret;
+
+ if (!*nr_zones)
+ return 0;
+
+ ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, *nr_zones,
+ copy_zone_info_cb, 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;
+ }
+ *nr_zones = ret;
+ if (!ret)
+ 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;
+ char devstr[sizeof(device->fs_info->sb->s_id) +
+ sizeof(" (device )") - 1];
+
+ 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 (!IS_ALIGNED(nr_sectors, zone_sectors))
+ zone_info->nr_zones++;
+
+ zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
+ if (!zone_info->seq_zones) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
+ if (!zone_info->empty_zones) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ zones = kcalloc(BTRFS_REPORT_NR_ZONES,
+ sizeof(struct blk_zone), GFP_KERNEL);
+ if (!zones) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* 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 out;
+
+ 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 out;
+ }
+
+ kfree(zones);
+
+ device->zone_info = zone_info;
+
+ devstr[0] = 0;
+ if (device->fs_info)
+ snprintf(devstr, sizeof(devstr), " (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;
+
+out:
+ kfree(zones);
+ bitmap_free(zone_info->empty_zones);
+ bitmap_free(zone_info->seq_zones);
+ 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;
+
+ bitmap_free(zone_info->seq_zones);
+ bitmap_free(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/zoned.h b/fs/btrfs/zoned.h
new file mode 100644
index 000000000000..e4a08ae0a96b
--- /dev/null
+++ b/fs/btrfs/zoned.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_ZONED_H
+#define BTRFS_ZONED_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
--
2.27.0
next prev parent reply other threads:[~2020-10-01 18:38 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-01 18:36 [PATCH v8 00/41] btrfs: zoned block device support Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 02/41] btrfs: introduce ZONED feature flag Naohiro Aota
2020-10-01 18:36 ` Naohiro Aota [this message]
2020-10-13 15:53 ` [PATCH v8 03/41] btrfs: Get zone information of zoned block devices David Sterba
2020-10-15 7:45 ` Johannes Thumshirn
2020-10-01 18:36 ` [PATCH v8 04/41] btrfs: Check and enable ZONED mode Naohiro Aota
2020-10-13 15:56 ` David Sterba
2020-10-28 14:49 ` Johannes Thumshirn
2020-10-13 16:13 ` David Sterba
2020-10-01 18:36 ` [PATCH v8 05/41] btrfs: introduce max_zone_append_size Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 06/41] btrfs: disallow space_cache in ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 07/41] btrfs: disallow NODATACOW " Naohiro Aota
2020-10-13 15:39 ` David Sterba
2020-10-21 8:53 ` Johannes Thumshirn
2020-10-01 18:36 ` [PATCH v8 08/41] btrfs: disable fallocate " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 09/41] btrfs: disallow mixed-bg " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 10/41] btrfs: disallow inode_cache " Naohiro Aota
2020-10-13 15:41 ` David Sterba
2020-10-22 6:48 ` Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 11/41] btrfs: implement log-structured superblock for " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 12/41] btrfs: implement zoned chunk allocator Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 13/41] btrfs: verify device extent is aligned to zone Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 14/41] btrfs: load zone's alloction offset Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 15/41] btrfs: emulate write pointer for conventional zones Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 16/41] btrfs: track unusable bytes for zones Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 17/41] btrfs: do sequential extent allocation in ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 18/41] btrfs: reset zones of unused block groups Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 19/41] btrfs: redirty released extent buffers in ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 20/41] btrfs: extract page adding function Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 21/41] btrfs: use bio_add_zone_append_page for zoned btrfs Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 22/41] btrfs: handle REQ_OP_ZONE_APPEND as writing Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 23/41] btrfs: split ordered extent when bio is sent Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 24/41] btrfs: extend btrfs_rmap_block for specifying a device Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 25/41] btrfs: use ZONE_APPEND write for ZONED btrfs Naohiro Aota
2020-10-13 16:45 ` David Sterba
2020-10-01 18:36 ` [PATCH v8 26/41] btrfs: enable zone append writing for direct IO Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 27/41] btrfs: introduce dedicated data write path for ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 28/41] btrfs: serialize meta IOs on " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 29/41] btrfs: wait existing extents before truncating Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 30/41] btrfs: avoid async metadata checksum on ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 31/41] btrfs: mark block groups to copy for device-replace Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 32/41] btrfs: implement cloning for ZONED device-replace Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 33/41] btrfs: implement copying " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 34/41] btrfs: support dev-replace in ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 35/41] btrfs: enable relocation " Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 36/41] btrfs: relocate block group to repair IO failure in ZONED Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 37/41] btrfs: split alloc_log_tree() Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group Naohiro Aota
2020-10-13 16:26 ` David Sterba
2020-10-15 7:21 ` Johannes Thumshirn
2020-10-01 18:36 ` [PATCH v8 39/41] btrfs: serialize log transaction on ZONED mode Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 40/41] btrfs: reorder log node allocation Naohiro Aota
2020-10-01 18:36 ` [PATCH v8 41/41] btrfs: enable to mount ZONED incompat flag Naohiro Aota
2020-10-02 13:39 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Martin K. Petersen
2020-10-05 1:46 ` Damien Le Moal
2020-10-05 13:43 ` Christoph Hellwig
2020-10-06 1:26 ` Martin K. Petersen
2020-10-06 5:12 ` Damien Le Moal
2020-10-09 15:40 ` [PATCH v8 00/41] btrfs: zoned block device support Josef Bacik
2020-10-12 9:17 ` Naohiro Aota
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