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* [PATCH v8 00/41] btrfs: zoned block device support
@ 2020-10-01 18:36 Naohiro Aota
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
  2020-10-09 15:40 ` [PATCH v8 00/41] btrfs: zoned block device support Josef Bacik
  0 siblings, 2 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This series adds zoned block device support to btrfs.

Changes from v7:
 - Use bio_add_hw_page() to build up bio to honor hardware restrictions
   - add bio_add_zone_append_page() as a wrapper of the function
 - Split file extent on submitting bio
   - If bio_add_zone_append_page() fails, split the file extent and send
     out bio
   - so, we can ensure one bio == one file extent
 - Fix build bot issues
 - Rebased on misc-next

Userland series will follow.

This version of ZONED btrfs switched from normal write command to zone
append write command. You do not need to specify LBA (at the write pointer)
to write for zone append write command. Instead, you only select a zone to
write with its start LBA. Then the device (NVMe ZNS), or the emulation of
zone append command in the sd driver in the case of SAS or SATA HDDs,
automatically writes the data at the write pointer position and return the
written LBA as a command reply.

The benefit of using the zone append write command is that write command
issuing order does not matter. So, we can eliminate block group lock and
utilize asynchronous checksum, which can reorder the IOs.

Eliminating the lock improves performance. In particular, on a workload
with massive competing to the same zone [1], we observed 36% performance
improvement compared to normal write.

[1] Fio running 16 jobs with 4KB random writes for 5 minutes

However, there are some limitations. We cannot use the non-SINGLE profile.
Supporting non-SINGLE profile with zone append writing is not trivial. For
example, in the DUP profile, we send a zone append writing IO to two zones
on a device. The device reply with written LBAs for the IOs. If the offsets
of the returned addresses from the beginning of the zone are different,
then it results in different logical addresses.

For the same reason, we cannot issue multiple IOs for one ordered extent.
Thus, the size of an ordered extent is limited under max_zone_append_size.
This limitation will cause fragmentation and increased usage of metadata.
In the future, we can add optimization to merge ordered extents after
end_bio.

* Patch series description

A zoned block device consists of a number of zones. Zones are either
conventional and accepting random writes or sequential and requiring
that writes be issued in LBA order from each zone write pointer
position. This patch series ensures that the sequential write
constraint of sequential zones is respected while fundamentally not
changing BtrFS block and I/O management for block stored in
conventional zones.

To achieve this, the default chunk size of btrfs is changed on zoned
block devices so that chunks are always aligned to a zone. Allocation
of blocks within a chunk is changed so that the allocation is always
sequential from the beginning of the chunks. To do so, an allocation
pointer is added to block groups and used as the allocation hint.  The
allocation changes also ensure that blocks freed below the allocation
pointer are ignored, resulting in sequential block allocation
regardless of the chunk usage.

The zone of a chunk is reset to allow reuse of the zone only when the
block group is being freed, that is, when all the chunks of the block
group are unused.

For btrfs volumes composed of multiple zoned disks, a restriction is
added to ensure that all disks have the same zone size. This
restriction matches the existing constraint that all chunks in a block
group must have the same size.

* Enabling tree-log

The tree-log feature does not work on ZONED mode as is. Blocks for a
tree-log tree are allocated mixed with other metadata blocks, and btrfs
writes and syncs the tree-log blocks to devices at the time of fsync(),
which is different timing than a global transaction commit. As a result,
both writing tree-log blocks and writing other metadata blocks become
non-sequential writes which ZONED mode must avoid.

This series introduces a dedicated block group for tree-log blocks to
create two metadata writing streams, one for tree-log blocks and the
other for metadata blocks. As a result, each write stream can now be
written to devices separately and sequentially.

* Log-structured superblock

Superblock (and its copies) is the only data structure in btrfs which
has a fixed location on a device. Since we cannot overwrite in a
sequential write required zone, we cannot place superblock in the
zone.

This series implements superblock log writing. It uses two zones as a
circular buffer to write updated superblocks. Once the first zone is filled
up, start writing into the second zone. The first zone will be reset once
both zones are filled. We can determine the postion of the latest
superblock by reading the write pointer information from a device.

* Patch series organization

Patch 1 add bio_add_zone_append_page() as a wrapper of bio_add_hw_page().

Patch 2 introduces the ZONED incompatible feature flag to indicate that the
btrfs volume was formatted for use on zoned block devices.

Patches 3 to 5 implement functions to gather information on the zones of
the device (zones type, write pointer position, and max_zone_append_size).

Patches 6 to 10 disable features which are not compatible with the
sequential write constraints of zoned block devices. These includes
space_cache, NODATACOW, fallocate, MIXED_BG and inode cache.

Patch 11 implements the log-structured superblock writing.

Patches 12 and 13 tweak the device extent allocation for ZONED mode and add
verification to check if a device extent is properly aligned to zones.

Patches 14 to 17 implements sequential block allocator for ZONED mode.

Patch 18 implement a zone reset for unused block groups.

Patches 19 to 30 implement the writing path for several types of IO
(non-compressed data, direct IO, and metadata). These include re-dirtying
once-freed metadata blocks to prevent write holes.

Patches 31 to 40 tweak some btrfs features work with ZONED mode. These
include device-replace, relocation, repairing IO error, and tree-log.

Finally, patch 41 adds the ZONED feature to the list of supported features.

* Patch testing note

This series is based on kdave/for-5.5.

** Zone-aware util-linux

Since the log-structured superblock feature changed the location of
superblock magic, the current util-linux (libblkid) cannot detect ZONED
btrfs anymore. You need to apply a to-be posted patch to util-linux to make
it "zone aware".

** Testing device

You need devices with zone append writing command support to run ZONED
btrfs.

Other than real devices, null_blk supports zone append write command. You
can use memory backed null_blk to run the test on it. Following script
creates 12800 MB /dev/nullb0.

    sysfs=/sys/kernel/config/nullb/nullb0
    size=12800 # MB
    
    # drop nullb0
    if [[ -d $sysfs ]]; then
            echo 0 > "${sysfs}"/power
            rmdir $sysfs
    fi
    lsmod | grep -q null_blk && rmmod null_blk
    modprobe null_blk nr_devices=0
    
    mkdir "${sysfs}"
    
    echo "${size}" > "${sysfs}"/size
    echo 1 > "${sysfs}"/zoned
    echo 0 > "${sysfs}"/zone_nr_conv
    echo 1 > "${sysfs}"/memory_backed
    
    echo 1 > "${sysfs}"/power
    udevadm settle

Zoned SCSI devices such as SMR HDDs or scsi_debug also support the zone
append command as an emulated command within the SCSI sd driver. This
emulation is completely transparent to the user and provides the same
semantic as a NVMe ZNS native drive support.

Also, there is a qemu patch available to enable NVMe ZNS device.

** xfstests

We ran xfstests on ZONED btrfs, and, if we omit some cases that are known
to fail currently, all test cases pass.

Cases that can be ignored:
1) failing also with the regular btrfs on regular devices,
2) trying to test fallocate feature without testing with
   "_require_xfs_io_command "falloc"",
3) trying to test incompatible features for ZONED btrfs (e.g. RAID5/6)
4) trying to use incompatible setup for ZONED btrfs (e.g. dm-linear not
   aligned to zone boundary, swap)
5) trying to create a file system with too small size, (we require at least
   9 zones to initiate a ZONED btrfs)
6) dropping original MKFS_OPTIONS ("-O zoned"), so it cannot create ZONED
   btrfs (btrfs/003)
7) having ENOSPC which incurred by larger metadata block group size

I will send a patch series for xfstests to handle these cases (2-6)
properly.

Also, you need to apply the following patch if you run xfstests with
tcmu devices. xfstests btrfs/003 failed to "_devmgt_add" after
"_devmgt_remove" without this patch.

https://marc.info/?l=linux-scsi&m=156498625421698&w=2

v7 https://lore.kernel.org/linux-btrfs/20200911123259.3782926-1-naohiro.aota@wdc.com/
v6 https://lore.kernel.org/linux-btrfs/20191213040915.3502922-1-naohiro.aota@wdc.com/
v5 https://lore.kernel.org/linux-btrfs/20191204082513.857320-1-naohiro.aota@wdc.com/
v4 https://lwn.net/Articles/797061/
v3 https://lore.kernel.org/linux-btrfs/20190808093038.4163421-1-naohiro.aota@wdc.com/
v2 https://lore.kernel.org/linux-btrfs/20190607131025.31996-1-naohiro.aota@wdc.com/
v1 https://lore.kernel.org/linux-btrfs/20180809180450.5091-1-naota@elisp.net/

Changelog
v7:
 - Use zone append write command instead of normal write command
   - Bio issuing order does not matter
   - No need to use lock anymore
   - Can use asynchronous checksum
 - Removed RAID support for now
 - Rename HMZONED to ZONED
 - Split some patches
 - Rebased on kdave/for-5.9-rc3 + iomap direct IO
v6:
 - Use bitmap helpers (Johannes)
 - Code cleanup (Johannes)
 - Rebased on kdave/for-5.5
 - Enable the tree-log feature.
 - Treat conventional zones as sequential zones, so we can now allow
   mixed allocation of conventional zone and sequential write required
   zone to construct a block group.
 - Implement log-structured superblock
   - No need for one conventional zone at the beginning of a device.
 - Fix deadlock of direct IO writing
 - Fix building with !CONFIG_BLK_DEV_ZONED (Johannes)
 - Fix leak of zone_info (Johannes)
v5:
 - Rebased on kdave/for-5.5
 - Enable the tree-log feature.
 - Treat conventional zones as sequential zones, so we can now allow
   mixed allocation of conventional zone and sequential write required
   zone to construct a block group.
 - Implement log-structured superblock
   - No need for one conventional zone at the beginning of a device.
 - Fix deadlock of direct IO writing
 - Fix building with !CONFIG_BLK_DEV_ZONED (Johannes)
 - Fix leak of zone_info (Johannes)
v4:
 - Move memory allcation of zone informattion out of
   btrfs_get_dev_zones() (Anand)
 - Add disabled features table in commit log (Anand)
 - Ensure "max_chunk_size >= devs_min * data_stripes * zone_size"
v3:
 - Serialize allocation and submit_bio instead of bio buffering in
   btrfs_map_bio().
 -- Disable async checksum/submit in HMZONED mode
 - Introduce helper functions and hmzoned.c/h (Josef, David)
 - Add support for repairing IO failure
 - Add support for NOCOW direct IO write (Josef)
 - Disable preallocation entirely
 -- Disable INODE_MAP_CACHE
 -- relocation is reworked not to rely on preallocation in HMZONED mode
 - Disable NODATACOW
 -Disable MIXED_BG
 - Device extent that cover super block position is banned (David)
v2:
 - Add support for dev-replace
 -- To support dev-replace, moved submit_buffer one layer up. It now
    handles bio instead of btrfs_bio.
 -- Mark unmirrored Block Group readonly only when there are writable
    mirrored BGs. Necessary to handle degraded RAID.
 - Expire worker use vanilla delayed_work instead of btrfs's async-thread
 - Device extent allocator now ensure that region is on the same zone type.
 - Add delayed allocation shrinking.
 - Rename btrfs_drop_dev_zonetypes() to btrfs_destroy_dev_zonetypes
 - Fix
 -- Use SECTOR_SHIFT (Nikolay)
 -- Use btrfs_err (Nikolay)

Johannes Thumshirn (1):
  block: add bio_add_zone_append_page

Naohiro Aota (40):
  btrfs: introduce ZONED feature flag
  btrfs: Get zone information of zoned block devices
  btrfs: Check and enable ZONED mode
  btrfs: introduce max_zone_append_size
  btrfs: disallow space_cache in ZONED mode
  btrfs: disallow NODATACOW in ZONED mode
  btrfs: disable fallocate in ZONED mode
  btrfs: disallow mixed-bg in ZONED mode
  btrfs: disallow inode_cache in ZONED mode
  btrfs: implement log-structured superblock for ZONED mode
  btrfs: implement zoned chunk allocator
  btrfs: verify device extent is aligned to zone
  btrfs: load zone's alloction offset
  btrfs: emulate write pointer for conventional zones
  btrfs: track unusable bytes for zones
  btrfs: do sequential extent allocation in ZONED mode
  btrfs: reset zones of unused block groups
  btrfs: redirty released extent buffers in ZONED mode
  btrfs: extract page adding function
  btrfs: use bio_add_zone_append_page for zoned btrfs
  btrfs: handle REQ_OP_ZONE_APPEND as writing
  btrfs: split ordered extent when bio is sent
  btrfs: extend btrfs_rmap_block for specifying a device
  btrfs: use ZONE_APPEND write for ZONED btrfs
  btrfs: enable zone append writing for direct IO
  btrfs: introduce dedicated data write path for ZONED mode
  btrfs: serialize meta IOs on ZONED mode
  btrfs: wait existing extents before truncating
  btrfs: avoid async metadata checksum on ZONED mode
  btrfs: mark block groups to copy for device-replace
  btrfs: implement cloning for ZONED device-replace
  btrfs: implement copying for ZONED device-replace
  btrfs: support dev-replace in ZONED mode
  btrfs: enable relocation in ZONED mode
  btrfs: relocate block group to repair IO failure in ZONED
  btrfs: split alloc_log_tree()
  btrfs: extend zoned allocator to use dedicated tree-log block group
  btrfs: serialize log transaction on ZONED mode
  btrfs: reorder log node allocation
  btrfs: enable to mount ZONED incompat flag

 block/bio.c                 |   36 +
 fs/btrfs/Makefile           |    1 +
 fs/btrfs/block-group.c      |   85 ++-
 fs/btrfs/block-group.h      |   13 +
 fs/btrfs/ctree.h            |   12 +-
 fs/btrfs/dev-replace.c      |  187 ++++++
 fs/btrfs/dev-replace.h      |    3 +
 fs/btrfs/disk-io.c          |   82 ++-
 fs/btrfs/disk-io.h          |    2 +
 fs/btrfs/extent-tree.c      |  203 +++++-
 fs/btrfs/extent_io.c        |  136 +++-
 fs/btrfs/extent_io.h        |    2 +
 fs/btrfs/file.c             |    4 +
 fs/btrfs/free-space-cache.c |   58 ++
 fs/btrfs/free-space-cache.h |    4 +
 fs/btrfs/inode.c            |  153 ++++-
 fs/btrfs/ioctl.c            |    3 +
 fs/btrfs/ordered-data.c     |   76 +++
 fs/btrfs/ordered-data.h     |    6 +
 fs/btrfs/relocation.c       |   35 +-
 fs/btrfs/scrub.c            |  145 ++++
 fs/btrfs/space-info.c       |   13 +-
 fs/btrfs/space-info.h       |    4 +-
 fs/btrfs/super.c            |   13 +-
 fs/btrfs/sysfs.c            |    4 +
 fs/btrfs/transaction.c      |   10 +
 fs/btrfs/transaction.h      |    3 +
 fs/btrfs/tree-log.c         |   50 +-
 fs/btrfs/volumes.c          |  307 ++++++++-
 fs/btrfs/volumes.h          |    7 +
 fs/btrfs/zoned.c            | 1266 +++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h            |  279 ++++++++
 include/linux/bio.h         |    2 +
 include/uapi/linux/btrfs.h  |    1 +
 34 files changed, 3112 insertions(+), 93 deletions(-)
 create mode 100644 fs/btrfs/zoned.c
 create mode 100644 fs/btrfs/zoned.h

-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 01/41] block: add bio_add_zone_append_page
  2020-10-01 18:36 [PATCH v8 00/41] btrfs: zoned block device support Naohiro Aota
@ 2020-10-01 18:36 ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 02/41] btrfs: introduce ZONED feature flag Naohiro Aota
                     ` (40 more replies)
  2020-10-09 15:40 ` [PATCH v8 00/41] btrfs: zoned block device support Josef Bacik
  1 sibling, 41 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Johannes Thumshirn

From: Johannes Thumshirn <johannes.thumshirn@wdc.com>

Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which
is intended to be used by file systems that directly add pages to a bio
instead of using bio_iov_iter_get_pages().

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 block/bio.c         | 36 ++++++++++++++++++++++++++++++++++++
 include/linux/bio.h |  2 ++
 2 files changed, 38 insertions(+)

diff --git a/block/bio.c b/block/bio.c
index e865ea55b9f9..e0d41ccc4e90 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -853,6 +853,42 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio,
 }
 EXPORT_SYMBOL(bio_add_pc_page);
 
+/**
+ * bio_add_zone_append_page - attempt to add page to zone-append bio
+ * @bio: destination bio
+ * @page: page to add
+ * @len: vec entry length
+ * @offset: vec entry offset
+ *
+ * Attempt to add a page to the bio_vec maplist of a bio that will be submitted
+ * for a zone-append request. This can fail for a number of reasons, such as the
+ * bio being full or the target block device is not a zoned block device or
+ * other limitations of the target block device. The target block device must
+ * allow bio's up to PAGE_SIZE, so it is always possible to add a single page
+ * to an empty bio.
+ */
+int bio_add_zone_append_page(struct bio *bio, struct page *page,
+			     unsigned int len, unsigned int offset)
+{
+	struct request_queue *q;
+	bool same_page = false;
+
+	if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_ZONE_APPEND))
+		return 0;
+
+	if (WARN_ON_ONCE(!bio->bi_disk))
+		return 0;
+
+	q = bio->bi_disk->queue;
+
+	if (WARN_ON_ONCE(!blk_queue_is_zoned(q)))
+		return 0;
+
+	return bio_add_hw_page(q, bio, page, len, offset,
+			       queue_max_zone_append_sectors(q), &same_page);
+}
+EXPORT_SYMBOL_GPL(bio_add_zone_append_page);
+
 /**
  * __bio_try_merge_page - try appending data to an existing bvec.
  * @bio: destination bio
diff --git a/include/linux/bio.h b/include/linux/bio.h
index c6d765382926..7ef300cb4e9a 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -442,6 +442,8 @@ void bio_chain(struct bio *, struct bio *);
 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
 			   unsigned int, unsigned int);
+int bio_add_zone_append_page(struct bio *bio, struct page *page,
+			     unsigned int len, unsigned int offset);
 bool __bio_try_merge_page(struct bio *bio, struct page *page,
 		unsigned int len, unsigned int off, bool *same_page);
 void __bio_add_page(struct bio *bio, struct page *page,
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 02/41] btrfs: introduce ZONED feature flag
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 03/41] btrfs: Get zone information of zoned block devices Naohiro Aota
                     ` (39 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba
  Cc: hare, linux-fsdevel, Naohiro Aota, Anand Jain,
	Johannes Thumshirn, Damien Le Moal

This patch introduces the ZONED incompat flag. The flag indicates that the
volume management will satisfy the constraints imposed by host-managed
zoned block devices.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/sysfs.c           | 2 ++
 include/uapi/linux/btrfs.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 279d9262b676..828006020bbd 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -263,6 +263,7 @@ BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
+BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
 
 static struct attribute *btrfs_supported_feature_attrs[] = {
 	BTRFS_FEAT_ATTR_PTR(mixed_backref),
@@ -278,6 +279,7 @@ static struct attribute *btrfs_supported_feature_attrs[] = {
 	BTRFS_FEAT_ATTR_PTR(metadata_uuid),
 	BTRFS_FEAT_ATTR_PTR(free_space_tree),
 	BTRFS_FEAT_ATTR_PTR(raid1c34),
+	BTRFS_FEAT_ATTR_PTR(zoned),
 	NULL
 };
 
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index 2c39d15a2beb..5df73001aad4 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -307,6 +307,7 @@ struct btrfs_ioctl_fs_info_args {
 #define BTRFS_FEATURE_INCOMPAT_NO_HOLES		(1ULL << 9)
 #define BTRFS_FEATURE_INCOMPAT_METADATA_UUID	(1ULL << 10)
 #define BTRFS_FEATURE_INCOMPAT_RAID1C34		(1ULL << 11)
+#define BTRFS_FEATURE_INCOMPAT_ZONED		(1ULL << 12)
 
 struct btrfs_ioctl_feature_flags {
 	__u64 compat_flags;
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 03/41] btrfs: Get zone information of zoned block devices
  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
  2020-10-13 15:53     ` David Sterba
  2020-10-01 18:36   ` [PATCH v8 04/41] btrfs: Check and enable ZONED mode Naohiro Aota
                     ` (38 subsequent siblings)
  40 siblings, 1 reply; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba
  Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik, Damien Le Moal

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


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 04/41] btrfs: Check and enable ZONED mode
  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   ` [PATCH v8 03/41] btrfs: Get zone information of zoned block devices Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-13 15:56     ` David Sterba
  2020-10-13 16:13     ` David Sterba
  2020-10-01 18:36   ` [PATCH v8 05/41] btrfs: introduce max_zone_append_size Naohiro Aota
                     ` (37 subsequent siblings)
  40 siblings, 2 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba
  Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik, Damien Le Moal

This commit introduces the function btrfs_check_zoned_mode() to check if
ZONED flag is enabled on the file system and if the file system consists of
zoned devices with equal zone size.

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/ctree.h       |  3 ++
 fs/btrfs/dev-replace.c |  7 ++++
 fs/btrfs/disk-io.c     |  9 +++++
 fs/btrfs/super.c       |  1 +
 fs/btrfs/volumes.c     |  5 +++
 fs/btrfs/zoned.c       | 78 ++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h       | 26 ++++++++++++++
 7 files changed, 129 insertions(+)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index aac3d6f4e35b..1a51aeb15574 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -588,6 +588,9 @@ struct btrfs_fs_info {
 	struct btrfs_root *free_space_root;
 	struct btrfs_root *data_reloc_root;
 
+	/* Zone size when in ZONED mode */
+	u64 zone_size;
+
 	/* the log root tree is a directory of all the other log roots */
 	struct btrfs_root *log_root_tree;
 
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 6f6d77224c2b..5e3554482af1 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -238,6 +238,13 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 		return PTR_ERR(bdev);
 	}
 
+	if (!btrfs_check_device_zone_type(fs_info, bdev)) {
+		btrfs_err(fs_info,
+			  "zone type of target device mismatch with the filesystem!");
+		ret = -EINVAL;
+		goto error;
+	}
+
 	sync_blockdev(bdev);
 
 	list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 764001609a15..acf374b6e1ab 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -42,6 +42,7 @@
 #include "block-group.h"
 #include "discard.h"
 #include "space-info.h"
+#include "zoned.h"
 
 #define BTRFS_SUPER_FLAG_SUPP	(BTRFS_HEADER_FLAG_WRITTEN |\
 				 BTRFS_HEADER_FLAG_RELOC |\
@@ -3130,7 +3131,15 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
 
 	btrfs_free_extra_devids(fs_devices, 1);
 
+	ret = btrfs_check_zoned_mode(fs_info);
+	if (ret) {
+		btrfs_err(fs_info, "failed to init ZONED mode: %d",
+				ret);
+		goto fail_block_groups;
+	}
+
 	ret = btrfs_sysfs_add_fsid(fs_devices);
+
 	if (ret) {
 		btrfs_err(fs_info, "failed to init sysfs fsid interface: %d",
 				ret);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8840a4fa81eb..1b2399c9c94e 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -44,6 +44,7 @@
 #include "backref.h"
 #include "space-info.h"
 #include "sysfs.h"
+#include "zoned.h"
 #include "tests/btrfs-tests.h"
 #include "block-group.h"
 #include "discard.h"
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b0a7a820222e..dc21cb8cdea9 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2517,6 +2517,11 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	if (IS_ERR(bdev))
 		return PTR_ERR(bdev);
 
+	if (!btrfs_check_device_zone_type(fs_info, bdev)) {
+		ret = -EINVAL;
+		goto error;
+	}
+
 	if (fs_devices->seeding) {
 		seeding_dev = 1;
 		down_write(&sb->s_umount);
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 0c908f0e9469..7509888b457a 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -177,3 +177,81 @@ int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 
 	return 0;
 }
+
+int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+	struct btrfs_device *device;
+	u64 hmzoned_devices = 0;
+	u64 nr_devices = 0;
+	u64 zone_size = 0;
+	int incompat_zoned = btrfs_fs_incompat(fs_info, ZONED);
+	int ret = 0;
+
+	/* Count zoned devices */
+	list_for_each_entry(device, &fs_devices->devices, dev_list) {
+		enum blk_zoned_model model;
+
+		if (!device->bdev)
+			continue;
+
+		model = bdev_zoned_model(device->bdev);
+		if (model == BLK_ZONED_HM ||
+		    (model == BLK_ZONED_HA && incompat_zoned)) {
+			hmzoned_devices++;
+			if (!zone_size) {
+				zone_size = device->zone_info->zone_size;
+			} else if (device->zone_info->zone_size != zone_size) {
+				btrfs_err(fs_info,
+					  "Zoned block devices must have equal zone sizes");
+				ret = -EINVAL;
+				goto out;
+			}
+		}
+		nr_devices++;
+	}
+
+	if (!hmzoned_devices && !incompat_zoned)
+		goto out;
+
+	if (!hmzoned_devices && incompat_zoned) {
+		/* No zoned block device found on ZONED FS */
+		btrfs_err(fs_info,
+			  "ZONED enabled file system should have zoned devices");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (hmzoned_devices && !incompat_zoned) {
+		btrfs_err(fs_info,
+			  "Enable ZONED mode to mount HMZONED device");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (hmzoned_devices != nr_devices) {
+		btrfs_err(fs_info,
+			  "zoned devices cannot be mixed with regular devices");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * stripe_size is always aligned to BTRFS_STRIPE_LEN in
+	 * __btrfs_alloc_chunk(). Since we want stripe_len == zone_size,
+	 * check the alignment here.
+	 */
+	if (!IS_ALIGNED(zone_size, BTRFS_STRIPE_LEN)) {
+		btrfs_err(fs_info,
+			  "zone size is not aligned to BTRFS_STRIPE_LEN");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	fs_info->zone_size = zone_size;
+
+	btrfs_info(fs_info, "ZONED mode enabled, zone size %llu B",
+		   fs_info->zone_size);
+out:
+	return ret;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index e4a08ae0a96b..4341630cb756 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -9,6 +9,8 @@
 #ifndef BTRFS_ZONED_H
 #define BTRFS_ZONED_H
 
+#include <linux/blkdev.h>
+
 struct btrfs_zoned_device_info {
 	/*
 	 * Number of zones, zone size and types of zones if bdev is a
@@ -26,6 +28,7 @@ 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);
+int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -37,6 +40,14 @@ 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) { }
+static inline int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
+{
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
+	btrfs_err(fs_info, "Zoned block devices support is not enabled");
+	return -EOPNOTSUPP;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
@@ -89,4 +100,19 @@ static inline void btrfs_dev_clear_zone_empty(struct btrfs_device *device,
 	btrfs_dev_set_empty_zone_bit(device, pos, false);
 }
 
+static inline bool btrfs_check_device_zone_type(struct btrfs_fs_info *fs_info,
+						struct block_device *bdev)
+{
+	u64 zone_size;
+
+	if (btrfs_fs_incompat(fs_info, ZONED)) {
+		zone_size = (u64)bdev_zone_sectors(bdev) << SECTOR_SHIFT;
+		/* Do not allow non-zoned device */
+		return bdev_is_zoned(bdev) && fs_info->zone_size == zone_size;
+	}
+
+	/* Do not allow Host Manged zoned device */
+	return bdev_zoned_model(bdev) != BLK_ZONED_HM;
+}
+
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 05/41] btrfs: introduce max_zone_append_size
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (2 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 04/41] btrfs: Check and enable ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 06/41] btrfs: disallow space_cache in ZONED mode Naohiro Aota
                     ` (36 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Zone append write command has a maximum IO size restriction it accepts.
Introduce max_zone_append_size to zone_info and fs_into to track the value.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/ctree.h |  2 ++
 fs/btrfs/zoned.c | 17 +++++++++++++++--
 fs/btrfs/zoned.h |  1 +
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 1a51aeb15574..e6f0fe1920e9 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -590,6 +590,8 @@ struct btrfs_fs_info {
 
 	/* Zone size when in ZONED mode */
 	u64 zone_size;
+	/* max size to emit ZONE_APPEND write command */
+	u64 max_zone_append_size;
 
 	/* the log root tree is a directory of all the other log roots */
 	struct btrfs_root *log_root_tree;
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 7509888b457a..2e12fce81abf 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -53,6 +53,7 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device)
 {
 	struct btrfs_zoned_device_info *zone_info = NULL;
 	struct block_device *bdev = device->bdev;
+	struct request_queue *q = bdev_get_queue(bdev);
 	sector_t nr_sectors = bdev->bd_part->nr_sects;
 	sector_t sector = 0;
 	struct blk_zone *zones = NULL;
@@ -73,6 +74,8 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device)
 	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->max_zone_append_size =
+		(u64)queue_max_zone_append_sectors(q) << SECTOR_SHIFT;
 	zone_info->nr_zones = nr_sectors >> ilog2(bdev_zone_sectors(bdev));
 	if (!IS_ALIGNED(nr_sectors, zone_sectors))
 		zone_info->nr_zones++;
@@ -185,6 +188,7 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 	u64 hmzoned_devices = 0;
 	u64 nr_devices = 0;
 	u64 zone_size = 0;
+	u64 max_zone_append_size = 0;
 	int incompat_zoned = btrfs_fs_incompat(fs_info, ZONED);
 	int ret = 0;
 
@@ -198,15 +202,23 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 		model = bdev_zoned_model(device->bdev);
 		if (model == BLK_ZONED_HM ||
 		    (model == BLK_ZONED_HA && incompat_zoned)) {
+			struct btrfs_zoned_device_info *zone_info =
+				device->zone_info;
+
 			hmzoned_devices++;
 			if (!zone_size) {
-				zone_size = device->zone_info->zone_size;
-			} else if (device->zone_info->zone_size != zone_size) {
+				zone_size = zone_info->zone_size;
+			} else if (zone_info->zone_size != zone_size) {
 				btrfs_err(fs_info,
 					  "Zoned block devices must have equal zone sizes");
 				ret = -EINVAL;
 				goto out;
 			}
+			if (!max_zone_append_size ||
+			    (zone_info->max_zone_append_size &&
+			     zone_info->max_zone_append_size < max_zone_append_size))
+				max_zone_append_size =
+					zone_info->max_zone_append_size;
 		}
 		nr_devices++;
 	}
@@ -249,6 +261,7 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 	}
 
 	fs_info->zone_size = zone_size;
+	fs_info->max_zone_append_size = max_zone_append_size;
 
 	btrfs_info(fs_info, "ZONED mode enabled, zone size %llu B",
 		   fs_info->zone_size);
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 4341630cb756..f200b46a71fb 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -18,6 +18,7 @@ struct btrfs_zoned_device_info {
 	 */
 	u64 zone_size;
 	u8  zone_size_shift;
+	u64 max_zone_append_size;
 	u32 nr_zones;
 	unsigned long *seq_zones;
 	unsigned long *empty_zones;
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 06/41] btrfs: disallow space_cache in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (3 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 05/41] btrfs: introduce max_zone_append_size Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 07/41] btrfs: disallow NODATACOW " Naohiro Aota
                     ` (35 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

As updates to the space cache v1 are in-place, the space cache cannot be
located over sequential zones and there is no guarantees that the device
will have enough conventional zones to store this cache. Resolve this
problem by disabling completely the space cache v1.  This does not
introduces any problems with sequential block groups: all the free space is
located after the allocation pointer and no free space before the pointer.
There is no need to have such cache.

Note: we can technically use free-space-tree (space cache v2) on ZONED
mode. But, since ZONED mode now always allocate extents in a block group
sequentially regardless of underlying device zone type, it's no use to
enable and maintain the tree.

For the same reason, NODATACOW is also disabled.

Also INODE_MAP_CACHE is also disabled to avoid preallocation in the
INODE_MAP_CACHE inode.

In summary, ZONED will disable:

| Disabled features | Reason                                              |
|-------------------+-----------------------------------------------------|
| RAID/Dup          | Cannot handle two zone append writes to different   |
|                   | zones                                               |
|-------------------+-----------------------------------------------------|
| space_cache (v1)  | In-place updating                                   |
| NODATACOW         | In-place updating                                   |
|-------------------+-----------------------------------------------------|
| fallocate         | Reserved extent will be a write hole                |
| INODE_MAP_CACHE   | Need pre-allocation. (and will be deprecated?)      |
|-------------------+-----------------------------------------------------|
| MIXED_BG          | Allocated metadata region will be write holes for   |
|                   | data writes                                         |

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/super.c | 12 ++++++++++--
 fs/btrfs/zoned.c | 18 ++++++++++++++++++
 fs/btrfs/zoned.h |  5 +++++
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 1b2399c9c94e..dfdd4f161d16 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -525,8 +525,14 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
 	cache_gen = btrfs_super_cache_generation(info->super_copy);
 	if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE))
 		btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE);
-	else if (cache_gen)
-		btrfs_set_opt(info->mount_opt, SPACE_CACHE);
+	else if (cache_gen) {
+		if (btrfs_fs_incompat(info, ZONED)) {
+			btrfs_info(info,
+			"clearring existing space cache in ZONED mode");
+			btrfs_set_super_cache_generation(info->super_copy, 0);
+		} else
+			btrfs_set_opt(info->mount_opt, SPACE_CACHE);
+	}
 
 	/*
 	 * Even the options are empty, we still need to do extra check
@@ -985,6 +991,8 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
 		ret = -EINVAL;
 
 	}
+	if (!ret)
+		ret = btrfs_check_mountopts_zoned(info);
 	if (!ret && btrfs_test_opt(info, SPACE_CACHE))
 		btrfs_info(info, "disk space caching is enabled");
 	if (!ret && btrfs_test_opt(info, FREE_SPACE_TREE))
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 2e12fce81abf..1629e585ba8c 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -268,3 +268,21 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 out:
 	return ret;
 }
+
+int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
+{
+	if (!btrfs_fs_incompat(info, ZONED))
+		return 0;
+
+	/*
+	 * SPACE CACHE writing is not CoWed. Disable that to avoid write
+	 * errors in sequential zones.
+	 */
+	if (btrfs_test_opt(info, SPACE_CACHE)) {
+		btrfs_err(info,
+			  "space cache v1 not supportted in ZONED mode");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index f200b46a71fb..2e1983188e6f 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -30,6 +30,7 @@ int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 int btrfs_get_dev_zone_info(struct btrfs_device *device);
 void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
 int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info);
+int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -49,6 +50,10 @@ static inline int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 	btrfs_err(fs_info, "Zoned block devices support is not enabled");
 	return -EOPNOTSUPP;
 }
+static inline int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
+{
+	return 0;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 07/41] btrfs: disallow NODATACOW in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (4 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 06/41] btrfs: disallow space_cache in ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-13 15:39     ` David Sterba
  2020-10-01 18:36   ` [PATCH v8 08/41] btrfs: disable fallocate " Naohiro Aota
                     ` (34 subsequent siblings)
  40 siblings, 1 reply; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba
  Cc: hare, linux-fsdevel, Naohiro Aota, Johannes Thumshirn, Josef Bacik

NODATACOW implies overwriting the file data on a device, which is
impossible in sequential required zones. Disable NODATACOW globally with
mount option and per-file NODATACOW attribute by masking FS_NOCOW_FL.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/ioctl.c | 3 +++
 fs/btrfs/zoned.c | 6 ++++++
 2 files changed, 9 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index ab408a23ba32..5d592da4e2ff 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -91,6 +91,9 @@ struct btrfs_ioctl_send_args_32 {
 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
 		unsigned int flags)
 {
+	if (btrfs_fs_incompat(btrfs_sb(inode->i_sb), ZONED))
+		flags &= ~FS_NOCOW_FL;
+
 	if (S_ISDIR(inode->i_mode))
 		return flags;
 	else if (S_ISREG(inode->i_mode))
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 1629e585ba8c..6bce654bb0e8 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -284,5 +284,11 @@ int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
 		return -EOPNOTSUPP;
 	}
 
+	if (btrfs_test_opt(info, NODATACOW)) {
+		btrfs_err(info,
+		  "cannot enable nodatacow with ZONED mode");
+		return -EOPNOTSUPP;
+	}
+
 	return 0;
 }
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 08/41] btrfs: disable fallocate in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (5 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 07/41] btrfs: disallow NODATACOW " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 09/41] btrfs: disallow mixed-bg " Naohiro Aota
                     ` (33 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba
  Cc: hare, linux-fsdevel, Naohiro Aota, Johannes Thumshirn, Josef Bacik

fallocate() is implemented by reserving actual extent instead of
reservations. This can result in exposing the sequential write constraint
of host-managed zoned block devices to the application, which would break
the POSIX semantic for the fallocated file.  To avoid this, report
fallocate() as not supported when in ZONED mode for now.

In the future, we may be able to implement "in-memory" fallocate() in ZONED
mode by utilizing space_info->bytes_may_use or so.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/file.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 038e0afaf3d0..60a01e1347ba 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -3341,6 +3341,10 @@ static long btrfs_fallocate(struct file *file, int mode,
 	alloc_end = round_up(offset + len, blocksize);
 	cur_offset = alloc_start;
 
+	/* Do not allow fallocate in ZONED mode */
+	if (btrfs_fs_incompat(btrfs_sb(inode->i_sb), ZONED))
+		return -EOPNOTSUPP;
+
 	/* Make sure we aren't being give some crap mode */
 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
 		     FALLOC_FL_ZERO_RANGE))
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 09/41] btrfs: disallow mixed-bg in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (6 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 08/41] btrfs: disable fallocate " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 10/41] btrfs: disallow inode_cache " Naohiro Aota
                     ` (32 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik

Placing both data and metadata in a block group is impossible in ZONED
mode. For data, we can allocate a space for it and write it immediately
after the allocation. For metadata, however, we cannot do so, because the
logical addresses are recorded in other metadata buffers to build up the
trees. As a result, a data buffer can be placed after a metadata buffer,
which is not written yet. Writing out the data buffer will break the
sequential write rule.

This commit check and disallow MIXED_BG with ZONED mode.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/zoned.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 6bce654bb0e8..8cd43d2d5611 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -260,6 +260,13 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 		goto out;
 	}
 
+	if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
+		btrfs_err(fs_info,
+			  "ZONED mode is not allowed for mixed block groups");
+		ret = -EINVAL;
+		goto out;
+	}
+
 	fs_info->zone_size = zone_size;
 	fs_info->max_zone_append_size = max_zone_append_size;
 
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 10/41] btrfs: disallow inode_cache in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (7 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 09/41] btrfs: disallow mixed-bg " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-13 15:41     ` David Sterba
  2020-10-01 18:36   ` [PATCH v8 11/41] btrfs: implement log-structured superblock for " Naohiro Aota
                     ` (31 subsequent siblings)
  40 siblings, 1 reply; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik

inode_cache use pre-allocation to write its cache data. However,
pre-allocation is completely disabled in ZONED mode.

We can technically enable inode_cache in the same way as relocation.
However, inode_cache is rarely used and the man page discourage using it.
So, let's just disable it for now.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/zoned.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 8cd43d2d5611..e47698d313a5 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -297,5 +297,11 @@ int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
 		return -EOPNOTSUPP;
 	}
 
+	if (btrfs_test_pending(info, SET_INODE_MAP_CACHE)) {
+		btrfs_err(info,
+		  "cannot enable inode map caching with ZONED mode");
+		return -EOPNOTSUPP;
+	}
+
 	return 0;
 }
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 11/41] btrfs: implement log-structured superblock for ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (8 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 10/41] btrfs: disallow inode_cache " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 12/41] btrfs: implement zoned chunk allocator Naohiro Aota
                     ` (30 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Superblock (and its copies) is the only data structure in btrfs which has a
fixed location on a device. Since we cannot overwrite in a sequential write
required zone, we cannot place superblock in the zone. One easy solution is
limiting superblock and copies to be placed only in conventional zones.
However, this method has two downsides: one is reduced number of superblock
copies. The location of the second copy of superblock is 256GB, which is in
a sequential write required zone on typical devices in the market today.
So, the number of superblock and copies is limited to be two.  Second
downside is that we cannot support devices which have no conventional zones
at all.

To solve these two problems, we employ superblock log writing. It uses two
zones as a circular buffer to write updated superblocks. Once the first
zone is filled up, start writing into the second buffer. Then, when the
both zones are filled up and before start writing to the first zone again,
it reset the first zone.

We can determine the position of the latest superblock by reading write
pointer information from a device. One corner case is when the both zones
are full. For this situation, we read out the last superblock of each
zone, and compare them to determine which zone is older.

The following zones are reserved as the circular buffer on ZONED btrfs.

- The primary superblock: zones 0 and 1
- The first copy: zones 16 and 17
- The second copy: zones 1024 or zone at 256GB which is minimum, and next
  to it

If these reserved zones are conventional, superblock is written fixed at
the start of the zone without logging.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c |   9 ++
 fs/btrfs/disk-io.c     |  41 +++++-
 fs/btrfs/scrub.c       |   3 +
 fs/btrfs/volumes.c     |  21 ++-
 fs/btrfs/zoned.c       | 304 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h       |  40 ++++++
 6 files changed, 406 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index c0f1d6818df7..0ce68aef2dd7 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1723,6 +1723,7 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 static int exclude_super_stripes(struct btrfs_block_group *cache)
 {
 	struct btrfs_fs_info *fs_info = cache->fs_info;
+	bool zoned = btrfs_fs_incompat(fs_info, ZONED);
 	u64 bytenr;
 	u64 *logical;
 	int stripe_len;
@@ -1744,6 +1745,14 @@ static int exclude_super_stripes(struct btrfs_block_group *cache)
 		if (ret)
 			return ret;
 
+		/* shouldn't have super stripes in sequential zones */
+		if (zoned && nr) {
+			btrfs_err(fs_info,
+				  "Zoned btrfs's block group %llu should not have super blocks",
+				  cache->start);
+			return -EUCLEAN;
+		}
+
 		while (nr--) {
 			u64 len = min_t(u64, stripe_len,
 				cache->start + cache->length - logical[nr]);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index acf374b6e1ab..61b50a7df27b 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3421,10 +3421,17 @@ struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
 {
 	struct btrfs_super_block *super;
 	struct page *page;
-	u64 bytenr;
+	u64 bytenr, bytenr_orig;
 	struct address_space *mapping = bdev->bd_inode->i_mapping;
+	int ret;
+
+	bytenr_orig = btrfs_sb_offset(copy_num);
+	ret = btrfs_sb_log_location_bdev(bdev, copy_num, READ, &bytenr);
+	if (ret == -ENOENT)
+		return ERR_PTR(-EINVAL);
+	else if (ret)
+		return ERR_PTR(ret);
 
-	bytenr = btrfs_sb_offset(copy_num);
 	if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
 		return ERR_PTR(-EINVAL);
 
@@ -3438,7 +3445,7 @@ struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
 		return ERR_PTR(-ENODATA);
 	}
 
-	if (btrfs_super_bytenr(super) != bytenr) {
+	if (btrfs_super_bytenr(super) != bytenr_orig) {
 		btrfs_release_disk_super(super);
 		return ERR_PTR(-EINVAL);
 	}
@@ -3493,7 +3500,8 @@ static int write_dev_supers(struct btrfs_device *device,
 	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	int i;
 	int errors = 0;
-	u64 bytenr;
+	int ret;
+	u64 bytenr, bytenr_orig;
 
 	if (max_mirrors == 0)
 		max_mirrors = BTRFS_SUPER_MIRROR_MAX;
@@ -3505,12 +3513,21 @@ static int write_dev_supers(struct btrfs_device *device,
 		struct bio *bio;
 		struct btrfs_super_block *disk_super;
 
-		bytenr = btrfs_sb_offset(i);
+		bytenr_orig = btrfs_sb_offset(i);
+		ret = btrfs_sb_log_location(device, i, WRITE, &bytenr);
+		if (ret == -ENOENT)
+			continue;
+		else if (ret < 0) {
+			btrfs_err(device->fs_info, "couldn't get super block location for mirror %d",
+				  i);
+			errors++;
+			continue;
+		}
 		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
 		    device->commit_total_bytes)
 			break;
 
-		btrfs_set_super_bytenr(sb, bytenr);
+		btrfs_set_super_bytenr(sb, bytenr_orig);
 
 		crypto_shash_digest(shash, (const char *)sb + BTRFS_CSUM_SIZE,
 				    BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE,
@@ -3555,6 +3572,7 @@ static int write_dev_supers(struct btrfs_device *device,
 			bio->bi_opf |= REQ_FUA;
 
 		btrfsic_submit_bio(bio);
+		btrfs_advance_sb_log(device, i);
 	}
 	return errors < i ? 0 : -1;
 }
@@ -3571,6 +3589,7 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
 	int i;
 	int errors = 0;
 	bool primary_failed = false;
+	int ret;
 	u64 bytenr;
 
 	if (max_mirrors == 0)
@@ -3579,7 +3598,15 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
 	for (i = 0; i < max_mirrors; i++) {
 		struct page *page;
 
-		bytenr = btrfs_sb_offset(i);
+		ret = btrfs_sb_log_location(device, i, READ, &bytenr);
+		if (ret == -ENOENT)
+			break;
+		else if (ret < 0) {
+			errors++;
+			if (i == 0)
+				primary_failed = true;
+			continue;
+		}
 		if (bytenr + BTRFS_SUPER_INFO_SIZE >=
 		    device->commit_total_bytes)
 			break;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index cf63f1e27a27..aa1b36cf5c88 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -20,6 +20,7 @@
 #include "rcu-string.h"
 #include "raid56.h"
 #include "block-group.h"
+#include "zoned.h"
 
 /*
  * This is only the first step towards a full-features scrub. It reads all
@@ -3704,6 +3705,8 @@ static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
 		if (bytenr + BTRFS_SUPER_INFO_SIZE >
 		    scrub_dev->commit_total_bytes)
 			break;
+		if (!btrfs_check_super_location(scrub_dev, bytenr))
+			continue;
 
 		ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
 				  scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index dc21cb8cdea9..9fd5a2b0a0a7 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1281,7 +1281,8 @@ void btrfs_release_disk_super(struct btrfs_super_block *super)
 }
 
 static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
-						       u64 bytenr)
+						       u64 bytenr,
+						       u64 bytenr_orig)
 {
 	struct btrfs_super_block *disk_super;
 	struct page *page;
@@ -1312,7 +1313,7 @@ static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev
 	/* align our pointer to the offset of the super block */
 	disk_super = p + offset_in_page(bytenr);
 
-	if (btrfs_super_bytenr(disk_super) != bytenr ||
+	if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
 	    btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
 		btrfs_release_disk_super(p);
 		return ERR_PTR(-EINVAL);
@@ -1347,7 +1348,8 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
 	bool new_device_added = false;
 	struct btrfs_device *device = NULL;
 	struct block_device *bdev;
-	u64 bytenr;
+	u64 bytenr, bytenr_orig;
+	int ret;
 
 	lockdep_assert_held(&uuid_mutex);
 
@@ -1357,14 +1359,18 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
 	 * So, we need to add a special mount option to scan for
 	 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
 	 */
-	bytenr = btrfs_sb_offset(0);
 	flags |= FMODE_EXCL;
 
 	bdev = blkdev_get_by_path(path, flags, holder);
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
 
-	disk_super = btrfs_read_disk_super(bdev, bytenr);
+	bytenr_orig = btrfs_sb_offset(0);
+	ret = btrfs_sb_log_location_bdev(bdev, 0, READ, &bytenr);
+	if (ret)
+		return ERR_PTR(ret);
+
+	disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr_orig);
 	if (IS_ERR(disk_super)) {
 		device = ERR_CAST(disk_super);
 		goto error_bdev_put;
@@ -2028,6 +2034,11 @@ void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
 		if (IS_ERR(disk_super))
 			continue;
 
+		if (bdev_is_zoned(bdev)) {
+			btrfs_reset_sb_log_zones(bdev, copy_num);
+			continue;
+		}
+
 		memset(&disk_super->magic, 0, sizeof(disk_super->magic));
 
 		page = virt_to_page(disk_super);
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index e47698d313a5..897ce30cf1a1 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -26,6 +26,27 @@ static int copy_zone_info_cb(struct blk_zone *zone, unsigned int idx,
 	return 0;
 }
 
+static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zone,
+			    u64 *wp_ret);
+
+static inline u32 sb_zone_number(u8 shift, int mirror)
+{
+	ASSERT(mirror < BTRFS_SUPER_MIRROR_MAX);
+
+	switch (mirror) {
+	case 0:
+		return 0;
+	case 1:
+		return 16;
+	case 2:
+		return min(btrfs_sb_offset(mirror) >> shift, 1024ULL);
+	default:
+		BUG();
+	}
+
+	return 0;
+}
+
 static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
 			       struct blk_zone *zones, unsigned int *nr_zones)
 {
@@ -126,6 +147,40 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device)
 		goto out;
 	}
 
+	nr_zones = 2;
+	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+		u32 sb_zone = sb_zone_number(zone_info->zone_size_shift, i);
+		u64 sb_wp;
+
+		if (sb_zone + 1 >= zone_info->nr_zones)
+			continue;
+
+		sector = sb_zone << (zone_info->zone_size_shift - SECTOR_SHIFT);
+		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT,
+					  &zone_info->sb_zones[2 * i],
+					  &nr_zones);
+		if (ret)
+			goto out;
+		if (nr_zones != 2) {
+			btrfs_err_in_rcu(device->fs_info,
+			"failed to read SB log zone info at device %s zone %u",
+					 rcu_str_deref(device->name), sb_zone);
+			ret = -EIO;
+			goto out;
+		}
+
+		ret = sb_write_pointer(device->bdev,
+				       &zone_info->sb_zones[2 * i], &sb_wp);
+		if (ret != -ENOENT && ret) {
+			btrfs_err_in_rcu(device->fs_info,
+				"SB log zone corrupted: device %s zone %u",
+					 rcu_str_deref(device->name), sb_zone);
+			ret = -EUCLEAN;
+			goto out;
+		}
+	}
+
+
 	kfree(zones);
 
 	device->zone_info = zone_info;
@@ -305,3 +360,252 @@ int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
 
 	return 0;
 }
+
+static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones,
+			    u64 *wp_ret)
+{
+	bool empty[2];
+	bool full[2];
+	sector_t sector;
+
+	ASSERT(zones[0].type != BLK_ZONE_TYPE_CONVENTIONAL &&
+	       zones[1].type != BLK_ZONE_TYPE_CONVENTIONAL);
+
+	empty[0] = zones[0].cond == BLK_ZONE_COND_EMPTY;
+	empty[1] = zones[1].cond == BLK_ZONE_COND_EMPTY;
+	full[0] = zones[0].cond == BLK_ZONE_COND_FULL;
+	full[1] = zones[1].cond == BLK_ZONE_COND_FULL;
+
+	/*
+	 * Possible state of log buffer zones
+	 *
+	 *   E I F
+	 * E * x 0
+	 * I 0 x 0
+	 * F 1 1 C
+	 *
+	 * Row: zones[0]
+	 * Col: zones[1]
+	 * State:
+	 *   E: Empty, I: In-Use, F: Full
+	 * Log position:
+	 *   *: Special case, no superblock is written
+	 *   0: Use write pointer of zones[0]
+	 *   1: Use write pointer of zones[1]
+	 *   C: Compare SBs from zones[0] and zones[1], use the newer one
+	 *   x: Invalid state
+	 */
+
+	if (empty[0] && empty[1]) {
+		/* special case to distinguish no superblock to read */
+		*wp_ret = zones[0].start << SECTOR_SHIFT;
+		return -ENOENT;
+	} else if (full[0] && full[1]) {
+		/* Compare two super blocks */
+		struct address_space *mapping = bdev->bd_inode->i_mapping;
+		struct page *page[2];
+		struct btrfs_super_block *super[2];
+		int i;
+
+		for (i = 0; i < 2; i++) {
+			u64 bytenr = ((zones[i].start + zones[i].len) << SECTOR_SHIFT) -
+				BTRFS_SUPER_INFO_SIZE;
+
+			page[i] = read_cache_page_gfp(mapping, bytenr >> PAGE_SHIFT, GFP_NOFS);
+			if (IS_ERR(page[i])) {
+				if (i == 1)
+					btrfs_release_disk_super(super[0]);
+				return PTR_ERR(page[i]);
+			}
+			super[i] = page_address(page[i]);
+		}
+
+		if (super[0]->generation > super[1]->generation)
+			sector = zones[1].start;
+		else
+			sector = zones[0].start;
+
+		for (i = 0; i < 2; i++)
+			btrfs_release_disk_super(super[i]);
+	} else if (!full[0] && (empty[1] || full[1])) {
+		sector = zones[0].wp;
+	} else if (full[0]) {
+		sector = zones[1].wp;
+	} else {
+		return -EUCLEAN;
+	}
+	*wp_ret = sector << SECTOR_SHIFT;
+	return 0;
+}
+
+static int sb_log_location(struct block_device *bdev, struct blk_zone *zones,
+			   int rw, u64 *bytenr_ret)
+{
+	u64 wp;
+	int ret;
+
+	if (zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL) {
+		*bytenr_ret = zones[0].start << SECTOR_SHIFT;
+		return 0;
+	}
+
+	ret = sb_write_pointer(bdev, zones, &wp);
+	if (ret != -ENOENT && ret < 0)
+		return ret;
+
+	if (rw == WRITE) {
+		struct blk_zone *reset = NULL;
+
+		if (wp == zones[0].start << SECTOR_SHIFT)
+			reset = &zones[0];
+		else if (wp == zones[1].start << SECTOR_SHIFT)
+			reset = &zones[1];
+
+		if (reset) {
+			ASSERT(reset->cond == BLK_ZONE_COND_FULL);
+
+			ret = blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
+					       reset->start, reset->len,
+					       GFP_NOFS);
+			if (ret)
+				return ret;
+
+			reset->cond = BLK_ZONE_COND_EMPTY;
+			reset->wp = reset->start;
+		}
+	} else if (ret != -ENOENT) {
+		/* For READ, we want the precious one */
+		if (wp == zones[0].start << SECTOR_SHIFT)
+			wp = (zones[1].start + zones[1].len) << SECTOR_SHIFT;
+		wp -= BTRFS_SUPER_INFO_SIZE;
+	}
+
+	*bytenr_ret = wp;
+	return 0;
+
+}
+
+int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,
+			       u64 *bytenr_ret)
+{
+	struct blk_zone zones[2];
+	unsigned int zone_sectors;
+	u32 sb_zone;
+	int ret;
+	u64 zone_size;
+	u8 zone_sectors_shift;
+	sector_t nr_sectors = bdev->bd_part->nr_sects;
+	u32 nr_zones;
+
+	if (!bdev_is_zoned(bdev)) {
+		*bytenr_ret = btrfs_sb_offset(mirror);
+		return 0;
+	}
+
+	ASSERT(rw == READ || rw == WRITE);
+
+	zone_sectors = bdev_zone_sectors(bdev);
+	if (!is_power_of_2(zone_sectors))
+		return -EINVAL;
+	zone_size = zone_sectors << SECTOR_SHIFT;
+	zone_sectors_shift = ilog2(zone_sectors);
+	nr_zones = nr_sectors >> zone_sectors_shift;
+
+	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
+	if (sb_zone + 1 >= nr_zones)
+		return -ENOENT;
+
+	ret = blkdev_report_zones(bdev, sb_zone << zone_sectors_shift, 2,
+				  copy_zone_info_cb, zones);
+	if (ret < 0)
+		return ret;
+	if (ret != 2)
+		return -EIO;
+
+	return sb_log_location(bdev, zones, rw, bytenr_ret);
+}
+
+int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
+			  u64 *bytenr_ret)
+{
+	struct btrfs_zoned_device_info *zinfo = device->zone_info;
+	u32 zone_num;
+
+	if (!zinfo) {
+		*bytenr_ret = btrfs_sb_offset(mirror);
+		return 0;
+	}
+
+	zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
+	if (zone_num + 1 >= zinfo->nr_zones)
+		return -ENOENT;
+
+	return sb_log_location(device->bdev, &zinfo->sb_zones[2 * mirror], rw,
+			       bytenr_ret);
+}
+
+static inline bool is_sb_log_zone(struct btrfs_zoned_device_info *zinfo,
+				  int mirror)
+{
+	u32 zone_num;
+
+	if (!zinfo)
+		return false;
+
+	zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
+	if (zone_num + 1 >= zinfo->nr_zones)
+		return false;
+
+	if (!test_bit(zone_num, zinfo->seq_zones))
+		return false;
+
+	return true;
+}
+
+void btrfs_advance_sb_log(struct btrfs_device *device, int mirror)
+{
+	struct btrfs_zoned_device_info *zinfo = device->zone_info;
+	struct blk_zone *zone;
+
+	if (!is_sb_log_zone(zinfo, mirror))
+		return;
+
+	zone = &zinfo->sb_zones[2 * mirror];
+	if (zone->cond != BLK_ZONE_COND_FULL) {
+		if (zone->cond == BLK_ZONE_COND_EMPTY)
+			zone->cond = BLK_ZONE_COND_IMP_OPEN;
+		zone->wp += (BTRFS_SUPER_INFO_SIZE >> SECTOR_SHIFT);
+		if (zone->wp == zone->start + zone->len)
+			zone->cond = BLK_ZONE_COND_FULL;
+		return;
+	}
+
+	zone++;
+	ASSERT(zone->cond != BLK_ZONE_COND_FULL);
+	if (zone->cond == BLK_ZONE_COND_EMPTY)
+		zone->cond = BLK_ZONE_COND_IMP_OPEN;
+	zone->wp += (BTRFS_SUPER_INFO_SIZE >> SECTOR_SHIFT);
+	if (zone->wp == zone->start + zone->len)
+		zone->cond = BLK_ZONE_COND_FULL;
+}
+
+int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror)
+{
+	sector_t zone_sectors;
+	sector_t nr_sectors = bdev->bd_part->nr_sects;
+	u8 zone_sectors_shift;
+	u32 sb_zone;
+	u32 nr_zones;
+
+	zone_sectors = bdev_zone_sectors(bdev);
+	zone_sectors_shift = ilog2(zone_sectors);
+	nr_zones = nr_sectors >> zone_sectors_shift;
+
+	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
+	if (sb_zone + 1 >= nr_zones)
+		return -ENOENT;
+
+	return blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
+				sb_zone << zone_sectors_shift, zone_sectors * 2,
+				GFP_NOFS);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 2e1983188e6f..60651040532a 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -10,6 +10,8 @@
 #define BTRFS_ZONED_H
 
 #include <linux/blkdev.h>
+#include "volumes.h"
+#include "disk-io.h"
 
 struct btrfs_zoned_device_info {
 	/*
@@ -22,6 +24,7 @@ struct btrfs_zoned_device_info {
 	u32 nr_zones;
 	unsigned long *seq_zones;
 	unsigned long *empty_zones;
+	struct blk_zone sb_zones[2 * BTRFS_SUPER_MIRROR_MAX];
 };
 
 #ifdef CONFIG_BLK_DEV_ZONED
@@ -31,6 +34,12 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device);
 void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
 int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info);
 int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info);
+int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,
+			       u64 *bytenr_ret);
+int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
+			  u64 *bytenr_ret);
+void btrfs_advance_sb_log(struct btrfs_device *device, int mirror);
+int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -54,6 +63,26 @@ static inline int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
 {
 	return 0;
 }
+static inline int btrfs_sb_log_location_bdev(struct block_device *bdev,
+					     int mirror, int rw,
+					     u64 *bytenr_ret)
+{
+	*bytenr_ret = btrfs_sb_offset(mirror);
+	return 0;
+}
+static inline int btrfs_sb_log_location(struct btrfs_device *device, int mirror,
+					int rw, u64 *bytenr_ret)
+{
+	*bytenr_ret = btrfs_sb_offset(mirror);
+	return 0;
+}
+static inline void btrfs_advance_sb_log(struct btrfs_device *device,
+					int mirror) { }
+static inline int btrfs_reset_sb_log_zones(struct block_device *bdev,
+					   int mirror)
+{
+	return 0;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
@@ -121,4 +150,15 @@ static inline bool btrfs_check_device_zone_type(struct btrfs_fs_info *fs_info,
 	return bdev_zoned_model(bdev) != BLK_ZONED_HM;
 }
 
+static inline bool btrfs_check_super_location(struct btrfs_device *device,
+					      u64 pos)
+{
+	/*
+	 * On a non-zoned device, any address is OK. On a zoned device,
+	 * non-SEQUENTIAL WRITE REQUIRED zones are capable.
+	 */
+	return device->zone_info == NULL ||
+	       !btrfs_dev_is_sequential(device, pos);
+}
+
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 12/41] btrfs: implement zoned chunk allocator
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (9 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 11/41] btrfs: implement log-structured superblock for " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 13/41] btrfs: verify device extent is aligned to zone Naohiro Aota
                     ` (29 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This commit implements zoned chunk/dev_extent allocator. The zoned
allocator align the device extents to zone boundaries so that a zone
reset affects only the device extent and does not change the state of
blocks in the neighbor device extents.

Also, it checks that a region allocation is not over any locations of
super block zones, and ensures the region is empty.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/volumes.c | 133 +++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/volumes.h |   1 +
 fs/btrfs/zoned.c   | 126 ++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h   |  30 ++++++++++
 4 files changed, 290 insertions(+)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9fd5a2b0a0a7..3b6f07330553 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1415,6 +1415,14 @@ static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
 	return false;
 }
 
+static inline u64 dev_extent_search_start_zoned(struct btrfs_device *device,
+						u64 start)
+{
+	start = max_t(u64, start,
+		      max_t(u64, device->zone_info->zone_size, SZ_1M));
+	return btrfs_zone_align(device, start);
+}
+
 static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
 {
 	switch (device->fs_devices->chunk_alloc_policy) {
@@ -1425,11 +1433,57 @@ static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
 		 * make sure to start at an offset of at least 1MB.
 		 */
 		return max_t(u64, start, SZ_1M);
+	case BTRFS_CHUNK_ALLOC_ZONED:
+		return dev_extent_search_start_zoned(device, start);
 	default:
 		BUG();
 	}
 }
 
+static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
+					u64 *hole_start, u64 *hole_size,
+					u64 num_bytes)
+{
+	u64 zone_size = device->zone_info->zone_size;
+	u64 pos;
+	int ret;
+	int changed = 0;
+
+	ASSERT(IS_ALIGNED(*hole_start, zone_size));
+
+	while (*hole_size > 0) {
+		pos = btrfs_find_allocatable_zones(device, *hole_start,
+						   *hole_start + *hole_size,
+						   num_bytes);
+		if (pos != *hole_start) {
+			*hole_size = *hole_start + *hole_size - pos;
+			*hole_start = pos;
+			changed = 1;
+			if (*hole_size < num_bytes)
+				break;
+		}
+
+		ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
+
+		/* range is ensured to be empty */
+		if (!ret)
+			return changed;
+
+		/* given hole range was invalid (outside of device) */
+		if (ret == -ERANGE) {
+			*hole_start += *hole_size;
+			*hole_size = 0;
+			return 1;
+		}
+
+		*hole_start += zone_size;
+		*hole_size -= zone_size;
+		changed = 1;
+	}
+
+	return changed;
+}
+
 /**
  * dev_extent_hole_check - check if specified hole is suitable for allocation
  * @device:	the device which we have the hole
@@ -1462,6 +1516,10 @@ static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
 	case BTRFS_CHUNK_ALLOC_REGULAR:
 		/* No extra check */
 		break;
+	case BTRFS_CHUNK_ALLOC_ZONED:
+		changed |= dev_extent_hole_check_zoned(device, hole_start,
+						       hole_size, num_bytes);
+		break;
 	default:
 		BUG();
 	}
@@ -1516,6 +1574,9 @@ static int find_free_dev_extent_start(struct btrfs_device *device,
 
 	search_start = dev_extent_search_start(device, search_start);
 
+	WARN_ON(device->zone_info &&
+		!IS_ALIGNED(num_bytes, device->zone_info->zone_size));
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -4906,6 +4967,39 @@ static void init_alloc_chunk_ctl_policy_regular(
 	ctl->dev_extent_min = BTRFS_STRIPE_LEN * ctl->dev_stripes;
 }
 
+static void
+init_alloc_chunk_ctl_policy_zoned(struct btrfs_fs_devices *fs_devices,
+				  struct alloc_chunk_ctl *ctl)
+{
+	u64 zone_size = fs_devices->fs_info->zone_size;
+	u64 limit;
+	int min_num_stripes = ctl->devs_min * ctl->dev_stripes;
+	int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies;
+	u64 min_chunk_size = min_data_stripes * zone_size;
+	u64 type = ctl->type;
+
+	ctl->max_stripe_size = zone_size;
+	if (type & BTRFS_BLOCK_GROUP_DATA) {
+		ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
+						 zone_size);
+	} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
+		ctl->max_chunk_size = ctl->max_stripe_size;
+	} else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
+		ctl->max_chunk_size = 2 * ctl->max_stripe_size;
+		ctl->devs_max = min_t(int, ctl->devs_max,
+				      BTRFS_MAX_DEVS_SYS_CHUNK);
+	} else {
+		BUG();
+	}
+
+	/* We don't want a chunk larger than 10% of writable space */
+	limit = max(round_down(div_factor(fs_devices->total_rw_bytes, 1),
+			       zone_size),
+		    min_chunk_size);
+	ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
+	ctl->dev_extent_min = zone_size * ctl->dev_stripes;
+}
+
 static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
 				 struct alloc_chunk_ctl *ctl)
 {
@@ -4926,6 +5020,9 @@ static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
 	case BTRFS_CHUNK_ALLOC_REGULAR:
 		init_alloc_chunk_ctl_policy_regular(fs_devices, ctl);
 		break;
+	case BTRFS_CHUNK_ALLOC_ZONED:
+		init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl);
+		break;
 	default:
 		BUG();
 	}
@@ -5052,6 +5149,40 @@ static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl,
 	return 0;
 }
 
+static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl,
+				    struct btrfs_device_info *devices_info)
+{
+	u64 zone_size = devices_info[0].dev->zone_info->zone_size;
+	int data_stripes;	/* number of stripes that count for
+				   block group size */
+
+	/*
+	 * It should hold because:
+	 *    dev_extent_min == dev_extent_want == zone_size * dev_stripes
+	 */
+	ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min);
+
+	ctl->stripe_size = zone_size;
+	ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
+	data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
+
+	/*
+	 * stripe_size is fixed in ZONED. Reduce ndevs instead.
+	 */
+	if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
+		ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies,
+					     ctl->stripe_size) + ctl->nparity,
+				     ctl->dev_stripes);
+		ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
+		data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
+		ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size);
+	}
+
+	ctl->chunk_size = ctl->stripe_size * data_stripes;
+
+	return 0;
+}
+
 static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
 			      struct alloc_chunk_ctl *ctl,
 			      struct btrfs_device_info *devices_info)
@@ -5079,6 +5210,8 @@ static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
 	switch (fs_devices->chunk_alloc_policy) {
 	case BTRFS_CHUNK_ALLOC_REGULAR:
 		return decide_stripe_size_regular(ctl, devices_info);
+	case BTRFS_CHUNK_ALLOC_ZONED:
+		return decide_stripe_size_zoned(ctl, devices_info);
 	default:
 		BUG();
 	}
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 4bbb15c4161f..c01dd5e40ec8 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -213,6 +213,7 @@ BTRFS_DEVICE_GETSET_FUNCS(bytes_used);
 
 enum btrfs_chunk_allocation_policy {
 	BTRFS_CHUNK_ALLOC_REGULAR,
+	BTRFS_CHUNK_ALLOC_ZONED,
 };
 
 struct btrfs_fs_devices {
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 897ce30cf1a1..b7cf837293e3 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -6,12 +6,14 @@
  *	Damien Le Moal	<damien.lemoal@wdc.com>
  */
 
+#include <linux/bitops.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
 #include "ctree.h"
 #include "volumes.h"
 #include "zoned.h"
 #include "rcu-string.h"
+#include "disk-io.h"
 
 /* Maximum number of zones to report per blkdev_report_zones() call */
 #define BTRFS_REPORT_NR_ZONES   4096
@@ -324,6 +326,7 @@ int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
 
 	fs_info->zone_size = zone_size;
 	fs_info->max_zone_append_size = max_zone_append_size;
+	fs_info->fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_ZONED;
 
 	btrfs_info(fs_info, "ZONED mode enabled, zone size %llu B",
 		   fs_info->zone_size);
@@ -609,3 +612,126 @@ int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror)
 				sb_zone << zone_sectors_shift, zone_sectors * 2,
 				GFP_NOFS);
 }
+
+/*
+ * btrfs_check_allocatable_zones - find allocatable zones within give region
+ * @device:	the device to allocate a region
+ * @hole_start: the position of the hole to allocate the region
+ * @num_bytes:	the size of wanted region
+ * @hole_size:	the size of hole
+ *
+ * Allocatable region should not contain any superblock locations.
+ */
+u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
+				 u64 hole_end, u64 num_bytes)
+{
+	struct btrfs_zoned_device_info *zinfo = device->zone_info;
+	u8 shift = zinfo->zone_size_shift;
+	u64 nzones = num_bytes >> shift;
+	u64 pos = hole_start;
+	u64 begin, end;
+	u64 sb_pos;
+	bool have_sb;
+	int i;
+
+	ASSERT(IS_ALIGNED(hole_start, zinfo->zone_size));
+	ASSERT(IS_ALIGNED(num_bytes, zinfo->zone_size));
+
+	while (pos < hole_end) {
+		begin = pos >> shift;
+		end = begin + nzones;
+
+		if (end > zinfo->nr_zones)
+			return hole_end;
+
+		/* check if zones in the region are all empty */
+		if (btrfs_dev_is_sequential(device, pos) &&
+		    find_next_zero_bit(zinfo->empty_zones, end, begin) != end) {
+			pos += zinfo->zone_size;
+			continue;
+		}
+
+		have_sb = false;
+		for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+			sb_pos = sb_zone_number(zinfo->zone_size, i);
+			if (!(end < sb_pos || sb_pos + 1 < begin)) {
+				have_sb = true;
+				pos = (sb_pos + 2) << shift;
+				break;
+			}
+		}
+		if (!have_sb)
+			break;
+	}
+
+	return pos;
+}
+
+int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
+			    u64 length, u64 *bytes)
+{
+	int ret;
+
+	*bytes = 0;
+	ret = blkdev_zone_mgmt(device->bdev, REQ_OP_ZONE_RESET,
+			       physical >> SECTOR_SHIFT, length >> SECTOR_SHIFT,
+			       GFP_NOFS);
+	if (ret)
+		return ret;
+
+	*bytes = length;
+	while (length) {
+		btrfs_dev_set_zone_empty(device, physical);
+		physical += device->zone_info->zone_size;
+		length -= device->zone_info->zone_size;
+	}
+
+	return 0;
+}
+
+int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
+{
+	struct btrfs_zoned_device_info *zinfo = device->zone_info;
+	u8 shift = zinfo->zone_size_shift;
+	unsigned long begin = start >> shift;
+	unsigned long end = (start + size) >> shift;
+	u64 pos;
+	int ret;
+
+	ASSERT(IS_ALIGNED(start, zinfo->zone_size));
+	ASSERT(IS_ALIGNED(size, zinfo->zone_size));
+
+	if (end > zinfo->nr_zones)
+		return -ERANGE;
+
+	/* all the zones are conventional */
+	if (find_next_bit(zinfo->seq_zones, begin, end) == end)
+		return 0;
+
+	/* all the zones are sequential and empty */
+	if (find_next_zero_bit(zinfo->seq_zones, begin, end) == end &&
+	    find_next_zero_bit(zinfo->empty_zones, begin, end) == end)
+		return 0;
+
+	for (pos = start; pos < start + size; pos += zinfo->zone_size) {
+		u64 reset_bytes;
+
+		if (!btrfs_dev_is_sequential(device, pos) ||
+		    btrfs_dev_is_empty_zone(device, pos))
+			continue;
+
+		/* free regions should be empty */
+		btrfs_warn_in_rcu(
+			device->fs_info,
+			"resetting device %s zone %llu for allocation",
+			rcu_str_deref(device->name), pos >> shift);
+		WARN_ON_ONCE(1);
+
+		ret = btrfs_reset_device_zone(device, pos, zinfo->zone_size,
+					      &reset_bytes);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 60651040532a..02baed605752 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -40,6 +40,11 @@ int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
 			  u64 *bytenr_ret);
 void btrfs_advance_sb_log(struct btrfs_device *device, int mirror);
 int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror);
+u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
+				 u64 hole_end, u64 num_bytes);
+int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
+			    u64 length, u64 *bytes);
+int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -83,6 +88,23 @@ static inline int btrfs_reset_sb_log_zones(struct block_device *bdev,
 {
 	return 0;
 }
+static inline u64 btrfs_find_allocatable_zones(struct btrfs_device *device,
+					       u64 hole_start, u64 hole_end,
+					       u64 num_bytes)
+{
+	return hole_start;
+}
+static inline int btrfs_reset_device_zone(struct btrfs_device *device,
+					  u64 physical, u64 length, u64 *bytes)
+{
+	*bytes = 0;
+	return 0;
+}
+static inline int btrfs_ensure_empty_zones(struct btrfs_device *device,
+					   u64 start, u64 size)
+{
+	return 0;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
@@ -161,4 +183,12 @@ static inline bool btrfs_check_super_location(struct btrfs_device *device,
 	       !btrfs_dev_is_sequential(device, pos);
 }
 
+static inline u64 btrfs_zone_align(struct btrfs_device *device, u64 pos)
+{
+	if (!device->zone_info)
+		return pos;
+
+	return ALIGN(pos, device->zone_info->zone_size);
+}
+
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 13/41] btrfs: verify device extent is aligned to zone
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (10 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 12/41] btrfs: implement zoned chunk allocator Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 14/41] btrfs: load zone's alloction offset Naohiro Aota
                     ` (28 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This patch add a verification in verify_one_dev_extent() to check if the
device extent is aligned to zone boundary.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/volumes.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3b6f07330553..c22ea7f0551f 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -7779,6 +7779,20 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
 		ret = -EUCLEAN;
 		goto out;
 	}
+
+	if (dev->zone_info) {
+		u64 zone_size = dev->zone_info->zone_size;
+
+		if (!IS_ALIGNED(physical_offset, zone_size) ||
+		    !IS_ALIGNED(physical_len, zone_size)) {
+			btrfs_err(fs_info,
+"dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
+				  devid, physical_offset, physical_len);
+			ret = -EUCLEAN;
+			goto out;
+		}
+	}
+
 out:
 	free_extent_map(em);
 	return ret;
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 14/41] btrfs: load zone's alloction offset
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (11 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 13/41] btrfs: verify device extent is aligned to zone Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 15/41] btrfs: emulate write pointer for conventional zones Naohiro Aota
                     ` (27 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Zoned btrfs must allocate blocks at the zones' write pointer. The device's
write pointer position can be mapped to a logical address within a block
group. This commit adds "alloc_offset" to track the logical address.

This logical address is populated in btrfs_load_block-group_zone_info()
from write pointers of corresponding zones.

For now, zoned btrfs only support the SINGLE profile. Supporting non-SINGLE
profile with zone append writing is not trivial. For example, in the DUP
profile, we send a zone append writing IO to two zones on a device. The
device reply with written LBAs for the IOs. If the offsets of the returned
addresses from the beginning of the zone are different, then it results in
different logical addresses.

We need fine-grained logical to physical mapping to support such separated
physical address issue. Since it should require additional metadata type,
disable non-SINGLE profiles for now.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c |  15 ++++
 fs/btrfs/block-group.h |   6 ++
 fs/btrfs/zoned.c       | 153 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h       |   6 ++
 4 files changed, 180 insertions(+)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 0ce68aef2dd7..6de3d95ab9d9 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -15,6 +15,7 @@
 #include "delalloc-space.h"
 #include "discard.h"
 #include "raid56.h"
+#include "zoned.h"
 
 /*
  * Return target flags in extended format or 0 if restripe for this chunk_type
@@ -1935,6 +1936,13 @@ static int read_one_block_group(struct btrfs_fs_info *info,
 			goto error;
 	}
 
+	ret = btrfs_load_block_group_zone_info(cache);
+	if (ret) {
+		btrfs_err(info, "failed to load zone info of bg %llu",
+			  cache->start);
+		goto error;
+	}
+
 	/*
 	 * We need to exclude the super stripes now so that the space info has
 	 * super bytes accounted for, otherwise we'll think we have more space
@@ -2161,6 +2169,13 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	cache->last_byte_to_unpin = (u64)-1;
 	cache->cached = BTRFS_CACHE_FINISHED;
 	cache->needs_free_space = 1;
+
+	ret = btrfs_load_block_group_zone_info(cache);
+	if (ret) {
+		btrfs_put_block_group(cache);
+		return ret;
+	}
+
 	ret = exclude_super_stripes(cache);
 	if (ret) {
 		/* We may have excluded something, so call this just in case */
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index adfd7583a17b..14e3043c9ce7 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -183,6 +183,12 @@ struct btrfs_block_group {
 
 	/* Record locked full stripes for RAID5/6 block group */
 	struct btrfs_full_stripe_locks_tree full_stripe_locks_root;
+
+	/*
+	 * Allocation offset for the block group to implement sequential
+	 * allocation. This is used only with ZONED mode enabled.
+	 */
+	u64 alloc_offset;
 };
 
 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index b7cf837293e3..33853f4d5a8b 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -9,14 +9,20 @@
 #include <linux/bitops.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
+#include <linux/sched/mm.h>
 #include "ctree.h"
 #include "volumes.h"
 #include "zoned.h"
 #include "rcu-string.h"
 #include "disk-io.h"
+#include "block-group.h"
 
 /* Maximum number of zones to report per blkdev_report_zones() call */
 #define BTRFS_REPORT_NR_ZONES   4096
+/* Invalid allocation pointer value for missing devices */
+#define WP_MISSING_DEV ((u64)-1)
+/* Pseudo write pointer value for conventional zone */
+#define WP_CONVENTIONAL ((u64)-2)
 
 static int copy_zone_info_cb(struct blk_zone *zone, unsigned int idx,
 			     void *data)
@@ -735,3 +741,150 @@ int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
 
 	return 0;
 }
+
+int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
+{
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	struct extent_map_tree *em_tree = &fs_info->mapping_tree;
+	struct extent_map *em;
+	struct map_lookup *map;
+	struct btrfs_device *device;
+	u64 logical = cache->start;
+	u64 length = cache->length;
+	u64 physical = 0;
+	int ret;
+	int i;
+	unsigned int nofs_flag;
+	u64 *alloc_offsets = NULL;
+	u32 num_sequential = 0, num_conventional = 0;
+
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
+	/* Sanity check */
+	if (!IS_ALIGNED(length, fs_info->zone_size)) {
+		btrfs_err(fs_info, "unaligned block group at %llu + %llu",
+			  logical, length);
+		return -EIO;
+	}
+
+	/* Get the chunk mapping */
+	read_lock(&em_tree->lock);
+	em = lookup_extent_mapping(em_tree, logical, length);
+	read_unlock(&em_tree->lock);
+
+	if (!em)
+		return -EINVAL;
+
+	map = em->map_lookup;
+
+	/*
+	 * Get the zone type: if the group is mapped to a non-sequential zone,
+	 * there is no need for the allocation offset (fit allocation is OK).
+	 */
+	alloc_offsets = kcalloc(map->num_stripes, sizeof(*alloc_offsets),
+				GFP_NOFS);
+	if (!alloc_offsets) {
+		free_extent_map(em);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < map->num_stripes; i++) {
+		bool is_sequential;
+		struct blk_zone zone;
+
+		device = map->stripes[i].dev;
+		physical = map->stripes[i].physical;
+
+		if (device->bdev == NULL) {
+			alloc_offsets[i] = WP_MISSING_DEV;
+			continue;
+		}
+
+		is_sequential = btrfs_dev_is_sequential(device, physical);
+		if (is_sequential)
+			num_sequential++;
+		else
+			num_conventional++;
+
+		if (!is_sequential) {
+			alloc_offsets[i] = WP_CONVENTIONAL;
+			continue;
+		}
+
+		/*
+		 * This zone will be used for allocation, so mark this
+		 * zone non-empty.
+		 */
+		btrfs_dev_clear_zone_empty(device, physical);
+
+		/*
+		 * The group is mapped to a sequential zone. Get the zone write
+		 * pointer to determine the allocation offset within the zone.
+		 */
+		WARN_ON(!IS_ALIGNED(physical, fs_info->zone_size));
+		nofs_flag = memalloc_nofs_save();
+		ret = btrfs_get_dev_zone(device, physical, &zone);
+		memalloc_nofs_restore(nofs_flag);
+		if (ret == -EIO || ret == -EOPNOTSUPP) {
+			ret = 0;
+			alloc_offsets[i] = WP_MISSING_DEV;
+			continue;
+		} else if (ret) {
+			goto out;
+		}
+
+		switch (zone.cond) {
+		case BLK_ZONE_COND_OFFLINE:
+		case BLK_ZONE_COND_READONLY:
+			btrfs_err(fs_info, "Offline/readonly zone %llu",
+				  physical >> device->zone_info->zone_size_shift);
+			alloc_offsets[i] = WP_MISSING_DEV;
+			break;
+		case BLK_ZONE_COND_EMPTY:
+			alloc_offsets[i] = 0;
+			break;
+		case BLK_ZONE_COND_FULL:
+			alloc_offsets[i] = fs_info->zone_size;
+			break;
+		default:
+			/* Partially used zone */
+			alloc_offsets[i] =
+				((zone.wp - zone.start) << SECTOR_SHIFT);
+			break;
+		}
+	}
+
+	if (num_conventional > 0) {
+		/*
+		 * Since conventional zones does not have write pointer, we
+		 * cannot determine alloc_offset from the pointer
+		 */
+		ret = -EINVAL;
+		goto out;
+	}
+
+	switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
+	case 0: /* single */
+		cache->alloc_offset = alloc_offsets[0];
+		break;
+	case BTRFS_BLOCK_GROUP_DUP:
+	case BTRFS_BLOCK_GROUP_RAID1:
+	case BTRFS_BLOCK_GROUP_RAID0:
+	case BTRFS_BLOCK_GROUP_RAID10:
+	case BTRFS_BLOCK_GROUP_RAID5:
+	case BTRFS_BLOCK_GROUP_RAID6:
+		/* non-SINGLE profiles are not supported yet */
+	default:
+		btrfs_err(fs_info, "Unsupported profile on ZONED %s",
+			  btrfs_bg_type_to_raid_name(map->type));
+		ret = -EINVAL;
+		goto out;
+	}
+
+out:
+	kfree(alloc_offsets);
+	free_extent_map(em);
+
+	return ret;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 02baed605752..3e05a526f0fa 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -45,6 +45,7 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
 int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
 			    u64 length, u64 *bytes);
 int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
+int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -105,6 +106,11 @@ static inline int btrfs_ensure_empty_zones(struct btrfs_device *device,
 {
 	return 0;
 }
+static inline int btrfs_load_block_group_zone_info(
+	struct btrfs_block_group *cache)
+{
+	return 0;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 15/41] btrfs: emulate write pointer for conventional zones
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (12 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 14/41] btrfs: load zone's alloction offset Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 16/41] btrfs: track unusable bytes for zones Naohiro Aota
                     ` (26 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Conventional zones do not have a write pointer. So, we cannot use it to
determine the allocation offset if a block group contains a conventional
zone. Instead, we can consider the end of the last allocated extent int the
block group as an allocation offset.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/zoned.c | 119 ++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 113 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 33853f4d5a8b..3f65da0c4942 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -742,6 +742,104 @@ int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
 	return 0;
 }
 
+static int emulate_write_pointer(struct btrfs_block_group *cache,
+				 u64 *offset_ret)
+{
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	struct btrfs_root *root = fs_info->extent_root;
+	struct btrfs_path *path;
+	struct extent_buffer *leaf;
+	struct btrfs_key search_key;
+	struct btrfs_key found_key;
+	int slot;
+	int ret;
+	u64 length;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	search_key.objectid = cache->start + cache->length;
+	search_key.type = 0;
+	search_key.offset = 0;
+
+	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
+	if (ret < 0)
+		goto out;
+	ASSERT(ret != 0);
+	slot = path->slots[0];
+	leaf = path->nodes[0];
+	ASSERT(slot != 0);
+	slot--;
+	btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+	if (found_key.objectid < cache->start) {
+		*offset_ret = 0;
+	} else if (found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
+		struct btrfs_key extent_item_key;
+
+		if (found_key.objectid != cache->start) {
+			ret = -EUCLEAN;
+			goto out;
+		}
+
+		length = 0;
+
+		/* metadata may have METADATA_ITEM_KEY */
+		if (slot == 0) {
+			btrfs_set_path_blocking(path);
+			ret = btrfs_prev_leaf(root, path);
+			if (ret < 0)
+				goto out;
+			if (ret == 0) {
+				slot = btrfs_header_nritems(leaf) - 1;
+				btrfs_item_key_to_cpu(leaf, &extent_item_key,
+						      slot);
+			}
+		} else {
+			btrfs_item_key_to_cpu(leaf, &extent_item_key, slot - 1);
+			ret = 0;
+		}
+
+		if (ret == 0 &&
+		    extent_item_key.objectid == cache->start) {
+			if (extent_item_key.type == BTRFS_METADATA_ITEM_KEY)
+				length = fs_info->nodesize;
+			else if (extent_item_key.type == BTRFS_EXTENT_ITEM_KEY)
+				length = extent_item_key.offset;
+			else {
+				ret = -EUCLEAN;
+				goto out;
+			}
+		}
+
+		*offset_ret = length;
+	} else if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+		   found_key.type == BTRFS_METADATA_ITEM_KEY) {
+
+		if (found_key.type == BTRFS_EXTENT_ITEM_KEY)
+			length = found_key.offset;
+		else
+			length = fs_info->nodesize;
+
+		if (!(found_key.objectid >= cache->start &&
+		       found_key.objectid + length <=
+		       cache->start + cache->length)) {
+			ret = -EUCLEAN;
+			goto out;
+		}
+		*offset_ret = found_key.objectid + length - cache->start;
+	} else {
+		ret = -EUCLEAN;
+		goto out;
+	}
+	ret = 0;
+
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
 int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 {
 	struct btrfs_fs_info *fs_info = cache->fs_info;
@@ -756,6 +854,7 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 	int i;
 	unsigned int nofs_flag;
 	u64 *alloc_offsets = NULL;
+	u64 emulated_offset = 0;
 	u32 num_sequential = 0, num_conventional = 0;
 
 	if (!btrfs_fs_incompat(fs_info, ZONED))
@@ -856,12 +955,12 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 	}
 
 	if (num_conventional > 0) {
-		/*
-		 * Since conventional zones does not have write pointer, we
-		 * cannot determine alloc_offset from the pointer
-		 */
-		ret = -EINVAL;
-		goto out;
+		ret = emulate_write_pointer(cache, &emulated_offset);
+		if (ret || map->num_stripes == num_conventional) {
+			if (!ret)
+				cache->alloc_offset = emulated_offset;
+			goto out;
+		}
 	}
 
 	switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
@@ -883,6 +982,14 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 	}
 
 out:
+	/* an extent is allocated after the write pointer */
+	if (num_conventional && emulated_offset > cache->alloc_offset) {
+		btrfs_err(fs_info,
+			  "got wrong write pointer in BG %llu: %llu > %llu",
+			  logical, emulated_offset, cache->alloc_offset);
+		ret = -EIO;
+	}
+
 	kfree(alloc_offsets);
 	free_extent_map(em);
 
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 16/41] btrfs: track unusable bytes for zones
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (13 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 15/41] btrfs: emulate write pointer for conventional zones Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 17/41] btrfs: do sequential extent allocation in ZONED mode Naohiro Aota
                     ` (25 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

In zoned btrfs, once written, then freed region is never usable until
resetting underlying zones. We need to distinguish such unusable space from
usable free space. So, this commit introduces "zone_unusable" to block
group, and "bytes_zone_unusable" to space_info to track the unusable space.

Pinned bytes are always reclaimed to the unsable space. But, when an
allocated region is returned before using e.g., the block group becomes
read-only between allocation time and reservation time, we can safely
return the region to the block group. For the situation, this commit
introduces "btrfs_add_free_space_unused". This behave as the same as
btrfs_add_free_space() on regular btrfs. On zoned btrfs, it rewinds the
allocation offset.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c      | 19 +++++++++-----
 fs/btrfs/block-group.h      |  1 +
 fs/btrfs/extent-tree.c      | 15 ++++++++---
 fs/btrfs/free-space-cache.c | 52 +++++++++++++++++++++++++++++++++++++
 fs/btrfs/free-space-cache.h |  4 +++
 fs/btrfs/space-info.c       | 13 ++++++----
 fs/btrfs/space-info.h       |  4 ++-
 fs/btrfs/sysfs.c            |  2 ++
 fs/btrfs/zoned.c            | 22 ++++++++++++++++
 fs/btrfs/zoned.h            |  2 ++
 10 files changed, 118 insertions(+), 16 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 6de3d95ab9d9..e68e477d9160 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1080,12 +1080,15 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 		WARN_ON(block_group->space_info->total_bytes
 			< block_group->length);
 		WARN_ON(block_group->space_info->bytes_readonly
-			< block_group->length);
+			< block_group->length - block_group->zone_unusable);
+		WARN_ON(block_group->space_info->bytes_zone_unusable
+			< block_group->zone_unusable);
 		WARN_ON(block_group->space_info->disk_total
 			< block_group->length * factor);
 	}
 	block_group->space_info->total_bytes -= block_group->length;
-	block_group->space_info->bytes_readonly -= block_group->length;
+	block_group->space_info->bytes_readonly -=
+		(block_group->length - block_group->zone_unusable);
 	block_group->space_info->disk_total -= block_group->length * factor;
 
 	spin_unlock(&block_group->space_info->lock);
@@ -1229,7 +1232,7 @@ static int inc_block_group_ro(struct btrfs_block_group *cache, int force)
 	}
 
 	num_bytes = cache->length - cache->reserved - cache->pinned -
-		    cache->bytes_super - cache->used;
+		    cache->bytes_super - cache->zone_unusable - cache->used;
 
 	/*
 	 * Data never overcommits, even in mixed mode, so do just the straight
@@ -1973,6 +1976,8 @@ static int read_one_block_group(struct btrfs_fs_info *info,
 		btrfs_free_excluded_extents(cache);
 	}
 
+	btrfs_calc_zone_unusable(cache);
+
 	ret = btrfs_add_block_group_cache(info, cache);
 	if (ret) {
 		btrfs_remove_free_space_cache(cache);
@@ -1980,7 +1985,8 @@ static int read_one_block_group(struct btrfs_fs_info *info,
 	}
 	trace_btrfs_add_block_group(info, cache, 0);
 	btrfs_update_space_info(info, cache->flags, cache->length,
-				cache->used, cache->bytes_super, &space_info);
+				cache->used, cache->bytes_super,
+				cache->zone_unusable, &space_info);
 
 	cache->space_info = space_info;
 
@@ -2217,7 +2223,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used,
 	 */
 	trace_btrfs_add_block_group(fs_info, cache, 1);
 	btrfs_update_space_info(fs_info, cache->flags, size, bytes_used,
-				cache->bytes_super, &cache->space_info);
+				cache->bytes_super, 0, &cache->space_info);
 	btrfs_update_global_block_rsv(fs_info);
 
 	link_block_group(cache);
@@ -2325,7 +2331,8 @@ void btrfs_dec_block_group_ro(struct btrfs_block_group *cache)
 	spin_lock(&cache->lock);
 	if (!--cache->ro) {
 		num_bytes = cache->length - cache->reserved -
-			    cache->pinned - cache->bytes_super - cache->used;
+			    cache->pinned - cache->bytes_super -
+			    cache->zone_unusable - cache->used;
 		sinfo->bytes_readonly -= num_bytes;
 		list_del_init(&cache->ro_list);
 	}
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 14e3043c9ce7..5be47f4bfea7 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -189,6 +189,7 @@ struct btrfs_block_group {
 	 * allocation. This is used only with ZONED mode enabled.
 	 */
 	u64 alloc_offset;
+	u64 zone_unusable;
 };
 
 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 3b21fee13e77..051e61f16cbe 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -34,6 +34,7 @@
 #include "block-group.h"
 #include "discard.h"
 #include "rcu-string.h"
+#include "zoned.h"
 
 #undef SCRAMBLE_DELAYED_REFS
 
@@ -2807,9 +2808,11 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 			cache = btrfs_lookup_block_group(fs_info, start);
 			BUG_ON(!cache); /* Logic error */
 
-			cluster = fetch_cluster_info(fs_info,
-						     cache->space_info,
-						     &empty_cluster);
+			if (!btrfs_fs_incompat(fs_info, ZONED))
+				cluster = fetch_cluster_info(fs_info,
+							     cache->space_info,
+							     &empty_cluster);
+
 			empty_cluster <<= 1;
 		}
 
@@ -2846,7 +2849,11 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 		space_info->max_extent_size = 0;
 		percpu_counter_add_batch(&space_info->total_bytes_pinned,
 			    -len, BTRFS_TOTAL_BYTES_PINNED_BATCH);
-		if (cache->ro) {
+		if (btrfs_fs_incompat(fs_info, ZONED)) {
+			/* need reset before reusing in zoned Block Group */
+			space_info->bytes_zone_unusable += len;
+			readonly = true;
+		} else if (cache->ro) {
 			space_info->bytes_readonly += len;
 			readonly = true;
 		}
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index af0013d3df63..65dd1538692a 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -2467,6 +2467,8 @@ int __btrfs_add_free_space(struct btrfs_fs_info *fs_info,
 	int ret = 0;
 	u64 filter_bytes = bytes;
 
+	ASSERT(!btrfs_fs_incompat(fs_info, ZONED));
+
 	info = kmem_cache_zalloc(btrfs_free_space_cachep, GFP_NOFS);
 	if (!info)
 		return -ENOMEM;
@@ -2524,11 +2526,44 @@ int __btrfs_add_free_space(struct btrfs_fs_info *fs_info,
 	return ret;
 }
 
+int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group,
+				 u64 bytenr, u64 size, bool used)
+{
+	struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
+	u64 offset = bytenr - block_group->start;
+	u64 to_free, to_unusable;
+
+	spin_lock(&ctl->tree_lock);
+	if (!used)
+		to_free = size;
+	else if (offset >= block_group->alloc_offset)
+		to_free = size;
+	else if (offset + size <= block_group->alloc_offset)
+		to_free = 0;
+	else
+		to_free = offset + size - block_group->alloc_offset;
+	to_unusable = size - to_free;
+
+	ctl->free_space += to_free;
+	block_group->zone_unusable += to_unusable;
+	spin_unlock(&ctl->tree_lock);
+	if (!used) {
+		spin_lock(&block_group->lock);
+		block_group->alloc_offset -= size;
+		spin_unlock(&block_group->lock);
+	}
+	return 0;
+}
+
 int btrfs_add_free_space(struct btrfs_block_group *block_group,
 			 u64 bytenr, u64 size)
 {
 	enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED;
 
+	if (btrfs_fs_incompat(block_group->fs_info, ZONED))
+		return __btrfs_add_free_space_zoned(block_group, bytenr, size,
+						    true);
+
 	if (btrfs_test_opt(block_group->fs_info, DISCARD_SYNC))
 		trim_state = BTRFS_TRIM_STATE_TRIMMED;
 
@@ -2537,6 +2572,16 @@ int btrfs_add_free_space(struct btrfs_block_group *block_group,
 				      bytenr, size, trim_state);
 }
 
+int btrfs_add_free_space_unused(struct btrfs_block_group *block_group,
+				u64 bytenr, u64 size)
+{
+	if (btrfs_fs_incompat(block_group->fs_info, ZONED))
+		return __btrfs_add_free_space_zoned(block_group, bytenr, size,
+						    false);
+
+	return btrfs_add_free_space(block_group, bytenr, size);
+}
+
 /*
  * This is a subtle distinction because when adding free space back in general,
  * we want it to be added as untrimmed for async. But in the case where we add
@@ -2547,6 +2592,10 @@ int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
 {
 	enum btrfs_trim_state trim_state = BTRFS_TRIM_STATE_UNTRIMMED;
 
+	if (btrfs_fs_incompat(block_group->fs_info, ZONED))
+		return __btrfs_add_free_space_zoned(block_group, bytenr, size,
+						    true);
+
 	if (btrfs_test_opt(block_group->fs_info, DISCARD_SYNC) ||
 	    btrfs_test_opt(block_group->fs_info, DISCARD_ASYNC))
 		trim_state = BTRFS_TRIM_STATE_TRIMMED;
@@ -2564,6 +2613,9 @@ int btrfs_remove_free_space(struct btrfs_block_group *block_group,
 	int ret;
 	bool re_search = false;
 
+	if (btrfs_fs_incompat(block_group->fs_info, ZONED))
+		return 0;
+
 	spin_lock(&ctl->tree_lock);
 
 again:
diff --git a/fs/btrfs/free-space-cache.h b/fs/btrfs/free-space-cache.h
index e3d5e0ad8f8e..7081216257a8 100644
--- a/fs/btrfs/free-space-cache.h
+++ b/fs/btrfs/free-space-cache.h
@@ -114,8 +114,12 @@ int __btrfs_add_free_space(struct btrfs_fs_info *fs_info,
 			   struct btrfs_free_space_ctl *ctl,
 			   u64 bytenr, u64 size,
 			   enum btrfs_trim_state trim_state);
+int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group,
+				 u64 bytenr, u64 size, bool used);
 int btrfs_add_free_space(struct btrfs_block_group *block_group,
 			 u64 bytenr, u64 size);
+int btrfs_add_free_space_unused(struct btrfs_block_group *block_group,
+				u64 bytenr, u64 size);
 int btrfs_add_free_space_async_trimmed(struct btrfs_block_group *block_group,
 				       u64 bytenr, u64 size);
 int btrfs_remove_free_space(struct btrfs_block_group *block_group,
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 64099565ab8f..bbbf3c1412a4 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -163,6 +163,7 @@ u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
 	ASSERT(s_info);
 	return s_info->bytes_used + s_info->bytes_reserved +
 		s_info->bytes_pinned + s_info->bytes_readonly +
+		s_info->bytes_zone_unusable +
 		(may_use_included ? s_info->bytes_may_use : 0);
 }
 
@@ -257,7 +258,7 @@ int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
 
 void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
 			     u64 total_bytes, u64 bytes_used,
-			     u64 bytes_readonly,
+			     u64 bytes_readonly, u64 bytes_zone_unusable,
 			     struct btrfs_space_info **space_info)
 {
 	struct btrfs_space_info *found;
@@ -273,6 +274,7 @@ void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
 	found->bytes_used += bytes_used;
 	found->disk_used += bytes_used * factor;
 	found->bytes_readonly += bytes_readonly;
+	found->bytes_zone_unusable += bytes_zone_unusable;
 	if (total_bytes > 0)
 		found->full = 0;
 	btrfs_try_granting_tickets(info, found);
@@ -422,10 +424,10 @@ static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 		   info->total_bytes - btrfs_space_info_used(info, true),
 		   info->full ? "" : "not ");
 	btrfs_info(fs_info,
-		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
+		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu zone_unusable=%llu",
 		info->total_bytes, info->bytes_used, info->bytes_pinned,
 		info->bytes_reserved, info->bytes_may_use,
-		info->bytes_readonly);
+		info->bytes_readonly, info->bytes_zone_unusable);
 
 	DUMP_BLOCK_RSV(fs_info, global_block_rsv);
 	DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
@@ -454,9 +456,10 @@ void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 	list_for_each_entry(cache, &info->block_groups[index], list) {
 		spin_lock(&cache->lock);
 		btrfs_info(fs_info,
-			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
+			"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %llu zone_unusable %s",
 			cache->start, cache->length, cache->used, cache->pinned,
-			cache->reserved, cache->ro ? "[readonly]" : "");
+			cache->reserved, cache->zone_unusable,
+			cache->ro ? "[readonly]" : "");
 		spin_unlock(&cache->lock);
 		btrfs_dump_free_space(cache, bytes);
 	}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index 5646393b928c..ee003ffba956 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -17,6 +17,8 @@ struct btrfs_space_info {
 	u64 bytes_may_use;	/* number of bytes that may be used for
 				   delalloc/allocations */
 	u64 bytes_readonly;	/* total bytes that are read only */
+	u64 bytes_zone_unusable;	/* total bytes that are unusable until
+					   resetting the device zone */
 
 	u64 max_extent_size;	/* This will hold the maximum extent size of
 				   the space info if we had an ENOSPC in the
@@ -119,7 +121,7 @@ DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
 			     u64 total_bytes, u64 bytes_used,
-			     u64 bytes_readonly,
+			     u64 bytes_readonly, u64 bytes_zone_unusable,
 			     struct btrfs_space_info **space_info);
 struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
 					       u64 flags);
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 828006020bbd..ea679803da9b 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -635,6 +635,7 @@ SPACE_INFO_ATTR(bytes_pinned);
 SPACE_INFO_ATTR(bytes_reserved);
 SPACE_INFO_ATTR(bytes_may_use);
 SPACE_INFO_ATTR(bytes_readonly);
+SPACE_INFO_ATTR(bytes_zone_unusable);
 SPACE_INFO_ATTR(disk_used);
 SPACE_INFO_ATTR(disk_total);
 BTRFS_ATTR(space_info, total_bytes_pinned,
@@ -648,6 +649,7 @@ static struct attribute *space_info_attrs[] = {
 	BTRFS_ATTR_PTR(space_info, bytes_reserved),
 	BTRFS_ATTR_PTR(space_info, bytes_may_use),
 	BTRFS_ATTR_PTR(space_info, bytes_readonly),
+	BTRFS_ATTR_PTR(space_info, bytes_zone_unusable),
 	BTRFS_ATTR_PTR(space_info, disk_used),
 	BTRFS_ATTR_PTR(space_info, disk_total),
 	BTRFS_ATTR_PTR(space_info, total_bytes_pinned),
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 3f65da0c4942..266daf7d60b7 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -995,3 +995,25 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 
 	return ret;
 }
+
+void btrfs_calc_zone_unusable(struct btrfs_block_group *cache)
+{
+	u64 unusable, free;
+
+	if (!btrfs_fs_incompat(cache->fs_info, ZONED))
+		return;
+
+	WARN_ON(cache->bytes_super != 0);
+	unusable = cache->alloc_offset - cache->used;
+	free = cache->length - cache->alloc_offset;
+	/* we only need ->free_space in ALLOC_SEQ BGs */
+	cache->last_byte_to_unpin = (u64)-1;
+	cache->cached = BTRFS_CACHE_FINISHED;
+	cache->free_space_ctl->free_space = free;
+	cache->zone_unusable = unusable;
+	/*
+	 * Should not have any excluded extents. Just
+	 * in case, though.
+	 */
+	btrfs_free_excluded_extents(cache);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 3e05a526f0fa..ab048176a397 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -46,6 +46,7 @@ int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
 			    u64 length, u64 *bytes);
 int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
 int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache);
+void btrfs_calc_zone_unusable(struct btrfs_block_group *cache);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -111,6 +112,7 @@ static inline int btrfs_load_block_group_zone_info(
 {
 	return 0;
 }
+static inline void btrfs_calc_zone_unusable(struct btrfs_block_group *cache) { }
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 17/41] btrfs: do sequential extent allocation in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (14 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 16/41] btrfs: track unusable bytes for zones Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 18/41] btrfs: reset zones of unused block groups Naohiro Aota
                     ` (24 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This commit implement sequential extent allocator for ZONED mode. The
allocator just need to check if there is enough space in the block group.
Since the allocator never manage bitmap or cluster. This commit also add
ASSERTs to the corresponding functions.

Actually, with zone append writing, it is unnecessary to track the
allocation offset. It only needs to check space availability. But, by
tracking the offset and returning the offset as an allocated region, we can
skip modification of ordered extents and checksum information when there is
no IO reordering.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c      |  4 ++
 fs/btrfs/extent-tree.c      | 82 ++++++++++++++++++++++++++++++++++---
 fs/btrfs/free-space-cache.c |  6 +++
 3 files changed, 86 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index e68e477d9160..f07c03445390 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -683,6 +683,10 @@ int btrfs_cache_block_group(struct btrfs_block_group *cache, int load_cache_only
 	struct btrfs_caching_control *caching_ctl;
 	int ret = 0;
 
+	/* Allocator for ZONED btrfs do not use the cache at all */
+	if (btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
 	caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
 	if (!caching_ctl)
 		return -ENOMEM;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 051e61f16cbe..2be93d0f5978 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3562,6 +3562,7 @@ btrfs_release_block_group(struct btrfs_block_group *cache,
 
 enum btrfs_extent_allocation_policy {
 	BTRFS_EXTENT_ALLOC_CLUSTERED,
+	BTRFS_EXTENT_ALLOC_ZONED,
 };
 
 /*
@@ -3814,6 +3815,55 @@ static int do_allocation_clustered(struct btrfs_block_group *block_group,
 	return find_free_extent_unclustered(block_group, ffe_ctl);
 }
 
+/*
+ * Simple allocator for sequential only block group. It only allows
+ * sequential allocation. No need to play with trees. This function
+ * also reserve the bytes as in btrfs_add_reserved_bytes.
+ */
+static int do_allocation_zoned(struct btrfs_block_group *block_group,
+			       struct find_free_extent_ctl *ffe_ctl,
+			       struct btrfs_block_group **bg_ret)
+{
+	struct btrfs_space_info *space_info = block_group->space_info;
+	struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
+	u64 start = block_group->start;
+	u64 num_bytes = ffe_ctl->num_bytes;
+	u64 avail;
+	int ret = 0;
+
+	ASSERT(btrfs_fs_incompat(block_group->fs_info, ZONED));
+
+	spin_lock(&space_info->lock);
+	spin_lock(&block_group->lock);
+
+	if (block_group->ro) {
+		ret = 1;
+		goto out;
+	}
+
+	avail = block_group->length - block_group->alloc_offset;
+	if (avail < num_bytes) {
+		ffe_ctl->max_extent_size = avail;
+		ret = 1;
+		goto out;
+	}
+
+	ffe_ctl->found_offset = start + block_group->alloc_offset;
+	block_group->alloc_offset += num_bytes;
+	spin_lock(&ctl->tree_lock);
+	ctl->free_space -= num_bytes;
+	spin_unlock(&ctl->tree_lock);
+
+	ASSERT(IS_ALIGNED(ffe_ctl->found_offset,
+			  block_group->fs_info->stripesize));
+	ffe_ctl->search_start = ffe_ctl->found_offset;
+
+out:
+	spin_unlock(&block_group->lock);
+	spin_unlock(&space_info->lock);
+	return ret;
+}
+
 static int do_allocation(struct btrfs_block_group *block_group,
 			 struct find_free_extent_ctl *ffe_ctl,
 			 struct btrfs_block_group **bg_ret)
@@ -3821,6 +3871,8 @@ static int do_allocation(struct btrfs_block_group *block_group,
 	switch (ffe_ctl->policy) {
 	case BTRFS_EXTENT_ALLOC_CLUSTERED:
 		return do_allocation_clustered(block_group, ffe_ctl, bg_ret);
+	case BTRFS_EXTENT_ALLOC_ZONED:
+		return do_allocation_zoned(block_group, ffe_ctl, bg_ret);
 	default:
 		BUG();
 	}
@@ -3835,6 +3887,9 @@ static void release_block_group(struct btrfs_block_group *block_group,
 		ffe_ctl->retry_clustered = false;
 		ffe_ctl->retry_unclustered = false;
 		break;
+	case BTRFS_EXTENT_ALLOC_ZONED:
+		/* nothing to do */
+		break;
 	default:
 		BUG();
 	}
@@ -3863,6 +3918,9 @@ static void found_extent(struct find_free_extent_ctl *ffe_ctl,
 	case BTRFS_EXTENT_ALLOC_CLUSTERED:
 		found_extent_clustered(ffe_ctl, ins);
 		break;
+	case BTRFS_EXTENT_ALLOC_ZONED:
+		/* nothing to do */
+		break;
 	default:
 		BUG();
 	}
@@ -3878,6 +3936,9 @@ static int chunk_allocation_failed(struct find_free_extent_ctl *ffe_ctl)
 		 */
 		ffe_ctl->loop = LOOP_NO_EMPTY_SIZE;
 		return 0;
+	case BTRFS_EXTENT_ALLOC_ZONED:
+		/* give up here */
+		return -ENOSPC;
 	default:
 		BUG();
 	}
@@ -4046,6 +4107,9 @@ static int prepare_allocation(struct btrfs_fs_info *fs_info,
 	case BTRFS_EXTENT_ALLOC_CLUSTERED:
 		return prepare_allocation_clustered(fs_info, ffe_ctl,
 						    space_info, ins);
+	case BTRFS_EXTENT_ALLOC_ZONED:
+		/* nothing to do */
+		return 0;
 	default:
 		BUG();
 	}
@@ -4109,6 +4173,9 @@ static noinline int find_free_extent(struct btrfs_root *root,
 	ffe_ctl.last_ptr = NULL;
 	ffe_ctl.use_cluster = true;
 
+	if (btrfs_fs_incompat(fs_info, ZONED))
+		ffe_ctl.policy = BTRFS_EXTENT_ALLOC_ZONED;
+
 	ins->type = BTRFS_EXTENT_ITEM_KEY;
 	ins->objectid = 0;
 	ins->offset = 0;
@@ -4251,20 +4318,23 @@ static noinline int find_free_extent(struct btrfs_root *root,
 		/* move on to the next group */
 		if (ffe_ctl.search_start + num_bytes >
 		    block_group->start + block_group->length) {
-			btrfs_add_free_space(block_group, ffe_ctl.found_offset,
-					     num_bytes);
+			btrfs_add_free_space_unused(block_group,
+						    ffe_ctl.found_offset,
+						    num_bytes);
 			goto loop;
 		}
 
 		if (ffe_ctl.found_offset < ffe_ctl.search_start)
-			btrfs_add_free_space(block_group, ffe_ctl.found_offset,
-				ffe_ctl.search_start - ffe_ctl.found_offset);
+			btrfs_add_free_space_unused(block_group,
+						    ffe_ctl.found_offset,
+						    ffe_ctl.search_start - ffe_ctl.found_offset);
 
 		ret = btrfs_add_reserved_bytes(block_group, ram_bytes,
 				num_bytes, delalloc);
 		if (ret == -EAGAIN) {
-			btrfs_add_free_space(block_group, ffe_ctl.found_offset,
-					     num_bytes);
+			btrfs_add_free_space_unused(block_group,
+						    ffe_ctl.found_offset,
+						    num_bytes);
 			goto loop;
 		}
 		btrfs_inc_block_group_reservations(block_group);
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 65dd1538692a..d6bc1f97cc78 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -2903,6 +2903,8 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group *block_group,
 	u64 align_gap_len = 0;
 	enum btrfs_trim_state align_gap_trim_state = BTRFS_TRIM_STATE_UNTRIMMED;
 
+	ASSERT(!btrfs_fs_incompat(block_group->fs_info, ZONED));
+
 	spin_lock(&ctl->tree_lock);
 	entry = find_free_space(ctl, &offset, &bytes_search,
 				block_group->full_stripe_len, max_extent_size);
@@ -3034,6 +3036,8 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group,
 	struct rb_node *node;
 	u64 ret = 0;
 
+	ASSERT(!btrfs_fs_incompat(block_group->fs_info, ZONED));
+
 	spin_lock(&cluster->lock);
 	if (bytes > cluster->max_size)
 		goto out;
@@ -3810,6 +3814,8 @@ int btrfs_trim_block_group(struct btrfs_block_group *block_group,
 	int ret;
 	u64 rem = 0;
 
+	ASSERT(!btrfs_fs_incompat(block_group->fs_info, ZONED));
+
 	*trimmed = 0;
 
 	spin_lock(&block_group->lock);
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 18/41] btrfs: reset zones of unused block groups
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (15 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 17/41] btrfs: do sequential extent allocation in ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 19/41] btrfs: redirty released extent buffers in ZONED mode Naohiro Aota
                     ` (23 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

For an ZONED volume, a block group maps to a zone of the device. For
deleted unused block groups, the zone of the block group can be reset to
rewind the zone write pointer at the start of the zone.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c |  8 ++++++--
 fs/btrfs/extent-tree.c | 17 ++++++++++++-----
 fs/btrfs/zoned.h       | 16 ++++++++++++++++
 3 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index f07c03445390..2241d04ad4aa 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1468,8 +1468,12 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 		if (!async_trim_enabled && btrfs_test_opt(fs_info, DISCARD_ASYNC))
 			goto flip_async;
 
-		/* DISCARD can flip during remount */
-		trimming = btrfs_test_opt(fs_info, DISCARD_SYNC);
+		/*
+		 * DISCARD can flip during remount. In ZONED mode, we need
+		 * to reset sequential required zones.
+		 */
+		trimming = btrfs_test_opt(fs_info, DISCARD_SYNC) ||
+				btrfs_fs_incompat(fs_info, ZONED);
 
 		/* Implicit trim during transaction commit. */
 		if (trimming)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2be93d0f5978..dbf178fee7c7 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1331,6 +1331,9 @@ int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
 
 		stripe = bbio->stripes;
 		for (i = 0; i < bbio->num_stripes; i++, stripe++) {
+			struct btrfs_device *dev = stripe->dev;
+			u64 physical = stripe->physical;
+			u64 length = stripe->length;
 			u64 bytes;
 			struct request_queue *req_q;
 
@@ -1338,14 +1341,18 @@ int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
 				ASSERT(btrfs_test_opt(fs_info, DEGRADED));
 				continue;
 			}
+
 			req_q = bdev_get_queue(stripe->dev->bdev);
-			if (!blk_queue_discard(req_q))
+			/* zone reset in ZONED mode */
+			if (btrfs_can_zone_reset(dev, physical, length))
+				ret = btrfs_reset_device_zone(dev, physical,
+							      length, &bytes);
+			else if (blk_queue_discard(req_q))
+				ret = btrfs_issue_discard(dev->bdev, physical,
+							  length, &bytes);
+			else
 				continue;
 
-			ret = btrfs_issue_discard(stripe->dev->bdev,
-						  stripe->physical,
-						  stripe->length,
-						  &bytes);
 			if (!ret) {
 				discarded_bytes += bytes;
 			} else if (ret != -EOPNOTSUPP) {
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index ab048176a397..e388189b28f0 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -199,4 +199,20 @@ static inline u64 btrfs_zone_align(struct btrfs_device *device, u64 pos)
 	return ALIGN(pos, device->zone_info->zone_size);
 }
 
+static inline bool btrfs_can_zone_reset(struct btrfs_device *device,
+					u64 physical, u64 length)
+{
+	u64 zone_size;
+
+	if (!btrfs_dev_is_sequential(device, physical))
+		return false;
+
+	zone_size = device->zone_info->zone_size;
+	if (!IS_ALIGNED(physical, zone_size) ||
+	    !IS_ALIGNED(length, zone_size))
+		return false;
+
+	return true;
+}
+
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 19/41] btrfs: redirty released extent buffers in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (16 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 18/41] btrfs: reset zones of unused block groups Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 20/41] btrfs: extract page adding function Naohiro Aota
                     ` (22 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Tree manipulating operations like merging nodes often release
once-allocated tree nodes. Btrfs cleans such nodes so that pages in the
node are not uselessly written out. On ZONED volumes, however, such
optimization blocks the following IOs as the cancellation of the write out
of the freed blocks breaks the sequential write sequence expected by the
device.

This patch introduces a list of clean and unwritten extent buffers that
have been released in a transaction. Btrfs redirty the buffer so that
btree_write_cache_pages() can send proper bios to the devices.

Besides it clears the entire content of the extent buffer not to confuse
raw block scanners e.g. btrfsck. By clearing the content,
csum_dirty_buffer() complains about bytenr mismatch, so avoid the checking
and checksum using newly introduced buffer flag EXTENT_BUFFER_NO_CHECK.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/disk-io.c     |  8 ++++++++
 fs/btrfs/extent-tree.c | 12 +++++++++++-
 fs/btrfs/extent_io.c   |  4 ++++
 fs/btrfs/extent_io.h   |  2 ++
 fs/btrfs/transaction.c | 10 ++++++++++
 fs/btrfs/transaction.h |  3 +++
 fs/btrfs/tree-log.c    |  6 ++++++
 fs/btrfs/zoned.c       | 37 +++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h       |  6 ++++++
 9 files changed, 87 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 61b50a7df27b..c872f051b0a5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -462,6 +462,12 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page)
 		return 0;
 
 	found_start = btrfs_header_bytenr(eb);
+
+	if (test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags)) {
+		WARN_ON(found_start != 0);
+		return 0;
+	}
+
 	/*
 	 * Please do not consolidate these warnings into a single if.
 	 * It is useful to know what went wrong.
@@ -4614,6 +4620,8 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
 				     EXTENT_DIRTY);
 	btrfs_destroy_pinned_extent(fs_info, &cur_trans->pinned_extents);
 
+	btrfs_free_redirty_list(cur_trans);
+
 	cur_trans->state =TRANS_STATE_COMPLETED;
 	wake_up(&cur_trans->commit_wait);
 }
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index dbf178fee7c7..c0e4a577c61c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3421,8 +3421,10 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 
 		if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
 			ret = check_ref_cleanup(trans, buf->start);
-			if (!ret)
+			if (!ret) {
+				btrfs_redirty_list_add(trans->transaction, buf);
 				goto out;
+			}
 		}
 
 		pin = 0;
@@ -3434,6 +3436,13 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
 			goto out;
 		}
 
+		if (btrfs_fs_incompat(fs_info, ZONED)) {
+			btrfs_redirty_list_add(trans->transaction, buf);
+			pin_down_extent(trans, cache, buf->start, buf->len, 1);
+			btrfs_put_block_group(cache);
+			goto out;
+		}
+
 		WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
 
 		btrfs_add_free_space(cache, buf->start, buf->len);
@@ -4767,6 +4776,7 @@ btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	__btrfs_tree_lock(buf, nest);
 	btrfs_clean_tree_block(buf);
 	clear_bit(EXTENT_BUFFER_STALE, &buf->bflags);
+	clear_bit(EXTENT_BUFFER_NO_CHECK, &buf->bflags);
 
 	btrfs_set_lock_blocking_write(buf);
 	set_extent_buffer_uptodate(buf);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 60f5f68d892d..e91c504fe973 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -24,6 +24,7 @@
 #include "rcu-string.h"
 #include "backref.h"
 #include "disk-io.h"
+#include "zoned.h"
 
 static struct kmem_cache *extent_state_cache;
 static struct kmem_cache *extent_buffer_cache;
@@ -4959,6 +4960,7 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
 
 	btrfs_leak_debug_add(&fs_info->eb_leak_lock, &eb->leak_list,
 			     &fs_info->allocated_ebs);
+	INIT_LIST_HEAD(&eb->release_list);
 
 	spin_lock_init(&eb->refs_lock);
 	atomic_set(&eb->refs, 1);
@@ -5744,6 +5746,8 @@ void write_extent_buffer(const struct extent_buffer *eb, const void *srcv,
 	char *src = (char *)srcv;
 	unsigned long i = start >> PAGE_SHIFT;
 
+	WARN_ON(test_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags));
+
 	if (check_eb_range(eb, start, len))
 		return;
 
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index f39d02e7f7ef..5f2ccfd0205e 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -30,6 +30,7 @@ enum {
 	EXTENT_BUFFER_IN_TREE,
 	/* write IO error */
 	EXTENT_BUFFER_WRITE_ERR,
+	EXTENT_BUFFER_NO_CHECK,
 };
 
 /* these are flags for __process_pages_contig */
@@ -107,6 +108,7 @@ struct extent_buffer {
 	 */
 	wait_queue_head_t read_lock_wq;
 	struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
+	struct list_head release_list;
 #ifdef CONFIG_BTRFS_DEBUG
 	int spinning_writers;
 	atomic_t spinning_readers;
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 84b506de2c91..fb02668026c9 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -22,6 +22,7 @@
 #include "qgroup.h"
 #include "block-group.h"
 #include "space-info.h"
+#include "zoned.h"
 
 #define BTRFS_ROOT_TRANS_TAG 0
 
@@ -336,6 +337,8 @@ static noinline int join_transaction(struct btrfs_fs_info *fs_info,
 	spin_lock_init(&cur_trans->dirty_bgs_lock);
 	INIT_LIST_HEAD(&cur_trans->deleted_bgs);
 	spin_lock_init(&cur_trans->dropped_roots_lock);
+	INIT_LIST_HEAD(&cur_trans->releasing_ebs);
+	spin_lock_init(&cur_trans->releasing_ebs_lock);
 	list_add_tail(&cur_trans->list, &fs_info->trans_list);
 	extent_io_tree_init(fs_info, &cur_trans->dirty_pages,
 			IO_TREE_TRANS_DIRTY_PAGES, fs_info->btree_inode);
@@ -2346,6 +2349,13 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans)
 		goto scrub_continue;
 	}
 
+	/*
+	 * At this point, we should have written the all tree blocks
+	 * allocated in this transaction. So it's now safe to free the
+	 * redirtyied extent buffers.
+	 */
+	btrfs_free_redirty_list(cur_trans);
+
 	ret = write_all_supers(fs_info, 0);
 	/*
 	 * the super is written, we can safely allow the tree-loggers
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 858d9153a1cd..380e0aaa15b3 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -92,6 +92,9 @@ struct btrfs_transaction {
 	 */
 	atomic_t pending_ordered;
 	wait_queue_head_t pending_wait;
+
+	spinlock_t releasing_ebs_lock;
+	struct list_head releasing_ebs;
 };
 
 #define __TRANS_FREEZABLE	(1U << 0)
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 56cbc1706b6f..5f585cf57383 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -20,6 +20,7 @@
 #include "inode-map.h"
 #include "block-group.h"
 #include "space-info.h"
+#include "zoned.h"
 
 /* magic values for the inode_only field in btrfs_log_inode:
  *
@@ -2742,6 +2743,8 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
 						free_extent_buffer(next);
 						return ret;
 					}
+					btrfs_redirty_list_add(
+						trans->transaction, next);
 				} else {
 					if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags))
 						clear_extent_buffer_dirty(next);
@@ -3277,6 +3280,9 @@ static void free_log_tree(struct btrfs_trans_handle *trans,
 	clear_extent_bits(&log->dirty_log_pages, 0, (u64)-1,
 			  EXTENT_DIRTY | EXTENT_NEW | EXTENT_NEED_WAIT);
 	extent_io_tree_release(&log->log_csum_range);
+
+	if (trans && log->node)
+		btrfs_redirty_list_add(trans->transaction, log->node);
 	btrfs_put_root(log);
 }
 
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 266daf7d60b7..88b45af60e4f 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -16,6 +16,7 @@
 #include "rcu-string.h"
 #include "disk-io.h"
 #include "block-group.h"
+#include "transaction.h"
 
 /* Maximum number of zones to report per blkdev_report_zones() call */
 #define BTRFS_REPORT_NR_ZONES   4096
@@ -1017,3 +1018,39 @@ void btrfs_calc_zone_unusable(struct btrfs_block_group *cache)
 	 */
 	btrfs_free_excluded_extents(cache);
 }
+
+void btrfs_redirty_list_add(struct btrfs_transaction *trans,
+			    struct extent_buffer *eb)
+{
+	struct btrfs_fs_info *fs_info = eb->fs_info;
+
+	if (!btrfs_fs_incompat(fs_info, ZONED) ||
+	    btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN) ||
+	    !list_empty(&eb->release_list))
+		return;
+
+	set_extent_buffer_dirty(eb);
+	set_extent_bits_nowait(&trans->dirty_pages, eb->start,
+			       eb->start + eb->len - 1, EXTENT_DIRTY);
+	memzero_extent_buffer(eb, 0, eb->len);
+	set_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags);
+
+	spin_lock(&trans->releasing_ebs_lock);
+	list_add_tail(&eb->release_list, &trans->releasing_ebs);
+	spin_unlock(&trans->releasing_ebs_lock);
+	atomic_inc(&eb->refs);
+}
+
+void btrfs_free_redirty_list(struct btrfs_transaction *trans)
+{
+	spin_lock(&trans->releasing_ebs_lock);
+	while (!list_empty(&trans->releasing_ebs)) {
+		struct extent_buffer *eb;
+
+		eb = list_first_entry(&trans->releasing_ebs,
+				      struct extent_buffer, release_list);
+		list_del_init(&eb->release_list);
+		free_extent_buffer(eb);
+	}
+	spin_unlock(&trans->releasing_ebs_lock);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index e388189b28f0..32446135e882 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -47,6 +47,9 @@ int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
 int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size);
 int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache);
 void btrfs_calc_zone_unusable(struct btrfs_block_group *cache);
+void btrfs_redirty_list_add(struct btrfs_transaction *trans,
+			    struct extent_buffer *eb);
+void btrfs_free_redirty_list(struct btrfs_transaction *trans);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -113,6 +116,9 @@ static inline int btrfs_load_block_group_zone_info(
 	return 0;
 }
 static inline void btrfs_calc_zone_unusable(struct btrfs_block_group *cache) { }
+static inline void btrfs_redirty_list_add(struct btrfs_transaction *trans,
+					  struct extent_buffer *eb) { }
+static inline void btrfs_free_redirty_list(struct btrfs_transaction *trans) { }
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 20/41] btrfs: extract page adding function
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (17 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 19/41] btrfs: redirty released extent buffers in ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 21/41] btrfs: use bio_add_zone_append_page for zoned btrfs Naohiro Aota
                     ` (21 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This commit extract page adding to bio part from submit_extent_page(). The
page is added only when bio_flags are the same, contiguous and the added
page fits in the same stripe as pages in the bio.

Condition checkings are reordered to allow early return to avoid possibly
heavy btrfs_bio_fits_in_stripe() calling.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/extent_io.c | 55 ++++++++++++++++++++++++++++++++------------
 1 file changed, 40 insertions(+), 15 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index e91c504fe973..17285048fb5a 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3012,6 +3012,43 @@ struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size)
 	return bio;
 }
 
+/**
+ * btrfs_bio_add_page	-	attempt to add a page to bio
+ * @bio:	destination bio
+ * @page:	page to add to the bio
+ * @logical:	offset of the new bio or to check whether we are adding
+ *              a contiguous page to the previous one
+ * @pg_offset:	starting offset in the page
+ * @size:	portion of page that we want to write
+ * @prev_bio_flags:  flags of previous bio to see if we can merge the current one
+ * @bio_flags:	flags of the current bio to see if we can merge them
+ *
+ * Attempt to add a page to bio considering stripe alignment etc. Return
+ * true if successfully page added. Otherwise, return false.
+ */
+bool btrfs_bio_add_page(struct bio *bio, struct page *page, u64 logical,
+			unsigned int size, unsigned int pg_offset,
+			unsigned long prev_bio_flags, unsigned long bio_flags)
+{
+	sector_t sector = logical >> SECTOR_SHIFT;
+	bool contig;
+
+	if (prev_bio_flags != bio_flags)
+		return false;
+
+	if (prev_bio_flags & EXTENT_BIO_COMPRESSED)
+		contig = bio->bi_iter.bi_sector == sector;
+	else
+		contig = bio_end_sector(bio) == sector;
+	if (!contig)
+		return false;
+
+	if (btrfs_bio_fits_in_stripe(page, size, bio, bio_flags))
+		return false;
+
+	return bio_add_page(bio, page, size, pg_offset) == size;
+}
+
 /*
  * @opf:	bio REQ_OP_* and REQ_* flags as one value
  * @wbc:	optional writeback control for io accounting
@@ -3040,27 +3077,15 @@ static int submit_extent_page(unsigned int opf,
 	int ret = 0;
 	struct bio *bio;
 	size_t page_size = min_t(size_t, size, PAGE_SIZE);
-	sector_t sector = offset >> 9;
 	struct extent_io_tree *tree = &BTRFS_I(page->mapping->host)->io_tree;
 
 	ASSERT(bio_ret);
 
 	if (*bio_ret) {
-		bool contig;
-		bool can_merge = true;
-
 		bio = *bio_ret;
-		if (prev_bio_flags & EXTENT_BIO_COMPRESSED)
-			contig = bio->bi_iter.bi_sector == sector;
-		else
-			contig = bio_end_sector(bio) == sector;
-
-		if (btrfs_bio_fits_in_stripe(page, page_size, bio, bio_flags))
-			can_merge = false;
-
-		if (prev_bio_flags != bio_flags || !contig || !can_merge ||
-		    force_bio_submit ||
-		    bio_add_page(bio, page, page_size, pg_offset) < page_size) {
+		if (force_bio_submit ||
+		    !btrfs_bio_add_page(bio, page, offset, page_size, pg_offset,
+					prev_bio_flags, bio_flags)) {
 			ret = submit_one_bio(bio, mirror_num, prev_bio_flags);
 			if (ret < 0) {
 				*bio_ret = NULL;
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 21/41] btrfs: use bio_add_zone_append_page for zoned btrfs
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (18 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 20/41] btrfs: extract page adding function Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 22/41] btrfs: handle REQ_OP_ZONE_APPEND as writing Naohiro Aota
                     ` (20 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

Zoned device has its own hardware restrictions e.g. max_zone_append_size
when using REQ_OP_ZONE_APPEND. To follow the restrictions, use
bio_add_zone_append_page() instead of bio_add_page(). We need target device
to use bio_add_zone_append_page(), so this commit reads the chunk
information to memoize the target device to btrfs_io_bio(bio)->device.

Currently, zoned btrfs only supports SINGLE profile. In the feature,
btrfs_io_bio can hold extent_map and check the restrictions for all the
devices the bio will be mapped.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/extent_io.c | 37 ++++++++++++++++++++++++++++++++++---
 1 file changed, 34 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 17285048fb5a..5ee94a2ffa22 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3032,6 +3032,7 @@ bool btrfs_bio_add_page(struct bio *bio, struct page *page, u64 logical,
 {
 	sector_t sector = logical >> SECTOR_SHIFT;
 	bool contig;
+	int ret;
 
 	if (prev_bio_flags != bio_flags)
 		return false;
@@ -3046,7 +3047,19 @@ bool btrfs_bio_add_page(struct bio *bio, struct page *page, u64 logical,
 	if (btrfs_bio_fits_in_stripe(page, size, bio, bio_flags))
 		return false;
 
-	return bio_add_page(bio, page, size, pg_offset) == size;
+	if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+		struct bio orig_bio;
+
+		memset(&orig_bio, 0, sizeof(orig_bio));
+		bio_copy_dev(&orig_bio, bio);
+		bio_set_dev(bio, btrfs_io_bio(bio)->device->bdev);
+		ret = bio_add_zone_append_page(bio, page, size, pg_offset);
+		bio_copy_dev(bio, &orig_bio);
+	} else {
+		ret = bio_add_page(bio, page, size, pg_offset);
+	}
+
+	return ret == size;
 }
 
 /*
@@ -3077,7 +3090,9 @@ static int submit_extent_page(unsigned int opf,
 	int ret = 0;
 	struct bio *bio;
 	size_t page_size = min_t(size_t, size, PAGE_SIZE);
-	struct extent_io_tree *tree = &BTRFS_I(page->mapping->host)->io_tree;
+	struct btrfs_inode *inode = BTRFS_I(page->mapping->host);
+	struct extent_io_tree *tree = &inode->io_tree;
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 
 	ASSERT(bio_ret);
 
@@ -3108,11 +3123,27 @@ static int submit_extent_page(unsigned int opf,
 	if (wbc) {
 		struct block_device *bdev;
 
-		bdev = BTRFS_I(page->mapping->host)->root->fs_info->fs_devices->latest_bdev;
+		bdev = fs_info->fs_devices->latest_bdev;
 		bio_set_dev(bio, bdev);
 		wbc_init_bio(wbc, bio);
 		wbc_account_cgroup_owner(wbc, page, page_size);
 	}
+	if (btrfs_fs_incompat(fs_info, ZONED) &&
+	    bio_op(bio) == REQ_OP_ZONE_APPEND) {
+		struct extent_map *em;
+		struct map_lookup *map;
+
+		em = btrfs_get_chunk_map(fs_info, offset, page_size);
+		if (IS_ERR(em))
+			return PTR_ERR(em);
+
+		map = em->map_lookup;
+		/* only support SINGLE profile for now */
+		ASSERT(map->num_stripes == 1);
+		btrfs_io_bio(bio)->device = map->stripes[0].dev;
+
+		free_extent_map(em);
+	}
 
 	*bio_ret = bio;
 
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 22/41] btrfs: handle REQ_OP_ZONE_APPEND as writing
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (19 preceding siblings ...)
  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   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 23/41] btrfs: split ordered extent when bio is sent Naohiro Aota
                     ` (19 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

ZONED btrfs uses REQ_OP_ZONE_APPEND for a bio going to actual devices. Let
btrfs_end_bio() and btrfs_op, who faces the bios, aware of it.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/volumes.c | 3 ++-
 fs/btrfs/volumes.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c22ea7f0551f..44ef7b2fb46c 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6447,7 +6447,8 @@ static void btrfs_end_bio(struct bio *bio)
 			struct btrfs_device *dev = btrfs_io_bio(bio)->device;
 
 			ASSERT(dev->bdev);
-			if (bio_op(bio) == REQ_OP_WRITE)
+			if (bio_op(bio) == REQ_OP_WRITE ||
+			    bio_op(bio) == REQ_OP_ZONE_APPEND)
 				btrfs_dev_stat_inc_and_print(dev,
 						BTRFS_DEV_STAT_WRITE_ERRS);
 			else if (!(bio->bi_opf & REQ_RAHEAD))
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index c01dd5e40ec8..f8fc3debd5e0 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -410,6 +410,7 @@ static inline enum btrfs_map_op btrfs_op(struct bio *bio)
 	case REQ_OP_DISCARD:
 		return BTRFS_MAP_DISCARD;
 	case REQ_OP_WRITE:
+	case REQ_OP_ZONE_APPEND:
 		return BTRFS_MAP_WRITE;
 	default:
 		WARN_ON_ONCE(1);
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 23/41] btrfs: split ordered extent when bio is sent
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (20 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 22/41] btrfs: handle REQ_OP_ZONE_APPEND as writing Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 24/41] btrfs: extend btrfs_rmap_block for specifying a device Naohiro Aota
                     ` (18 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

The device decides the written location of ZONE_APPEND write IO. Thus, we
cannot ensure two bios to be written continuously on the device. So, we
need to follow "one bio == one ordered extent" rule to ensure the region of
ordered extent maps to contiguous region on the disk.

This commit implements splitting of an ordered extent and an extent map on
submitting bio to follow the rule.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/inode.c        | 87 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/ordered-data.c | 73 ++++++++++++++++++++++++++++++++++
 fs/btrfs/ordered-data.h |  2 +
 3 files changed, 162 insertions(+)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 36efed0a24de..4bc975eafbd8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2158,6 +2158,87 @@ static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio,
 	return btrfs_csum_one_bio(BTRFS_I(inode), bio, 0, 0);
 }
 
+int extract_ordered_extent(struct inode *inode, struct bio *bio)
+{
+	struct btrfs_ordered_extent *ordered;
+	struct extent_map *em = NULL, *em_new = NULL;
+	struct page *page = bio_first_bvec_all(bio)->bv_page;
+	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+	u64 start = (u64)bio->bi_iter.bi_sector << SECTOR_SHIFT;
+	u64 len = bio->bi_iter.bi_size;
+	u64 end = start + len;
+	u64 ordered_end;
+	u64 pre, post;
+	int ret = 0;
+
+	ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode),
+					      page_offset(page));
+	if (WARN_ON_ONCE(!ordered))
+		return -EIO;
+
+	/* no need to split */
+	if (ordered->disk_num_bytes == len)
+		goto out;
+
+	/* cannot split once end_bio'd ordered extent */
+	if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* we cannot split compressed ordered extent */
+	if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* cannot split waietd ordered extent */
+	if (WARN_ON_ONCE(wq_has_sleeper(&ordered->wait))) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ordered_end = ordered->disk_bytenr + ordered->disk_num_bytes;
+	/* bio must be in one ordered extent */
+	if (WARN_ON_ONCE(start < ordered->disk_bytenr || end > ordered_end)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* checksum list should be empty */
+	if (WARN_ON_ONCE(!list_empty(&ordered->list))) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	pre = start - ordered->disk_bytenr;
+	post = ordered_end - end;
+
+	btrfs_split_ordered_extent(ordered, pre, post);
+
+	read_lock(&em_tree->lock);
+	em = lookup_extent_mapping(em_tree, ordered->file_offset, len);
+	if (!em) {
+		read_unlock(&em_tree->lock);
+		ret = -EIO;
+		goto out;
+	}
+	read_unlock(&em_tree->lock);
+
+	ASSERT(!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags));
+	em_new = create_io_em(BTRFS_I(inode), em->start + pre, len,
+			      em->start + pre, em->block_start + pre, len,
+			      len, len, BTRFS_COMPRESS_NONE,
+			      BTRFS_ORDERED_REGULAR);
+	free_extent_map(em_new);
+
+out:
+	free_extent_map(em);
+	btrfs_put_ordered_extent(ordered);
+
+	return ret;
+}
+
 /*
  * extent_io.c submission hook. This does the right thing for csum calculation
  * on write, or reading the csums from the tree before a read.
@@ -2192,6 +2273,12 @@ blk_status_t btrfs_submit_data_bio(struct inode *inode, struct bio *bio,
 	if (btrfs_is_free_space_inode(BTRFS_I(inode)))
 		metadata = BTRFS_WQ_ENDIO_FREE_SPACE;
 
+	if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+		ret = extract_ordered_extent(inode, bio);
+		if (ret)
+			goto out;
+	}
+
 	if (bio_op(bio) != REQ_OP_WRITE) {
 		ret = btrfs_bio_wq_end_io(fs_info, bio, metadata);
 		if (ret)
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 87bac9ecdf4c..7cd22cb07f26 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -943,6 +943,79 @@ void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
 	}
 }
 
+static void clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos,
+				 u64 len)
+{
+	struct inode *inode = ordered->inode;
+	u64 file_offset = ordered->file_offset + pos;
+	u64 disk_bytenr = ordered->disk_bytenr + pos;
+	u64 num_bytes = len;
+	u64 disk_num_bytes = len;
+	int type;
+	unsigned long flags_masked =
+		ordered->flags & ~(1 << BTRFS_ORDERED_DIRECT);
+	int compress_type = ordered->compress_type;
+	unsigned long weight;
+
+	weight = hweight_long(flags_masked);
+	WARN_ON_ONCE(weight > 1);
+	if (!weight)
+		type = 0;
+	else
+		type = __ffs(flags_masked);
+
+	ASSERT(!test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags));
+	if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered->flags)) {
+		WARN_ON_ONCE(1);
+		btrfs_add_ordered_extent_compress(BTRFS_I(inode), file_offset,
+						  disk_bytenr, num_bytes,
+						  disk_num_bytes, type,
+						  compress_type);
+	} else {
+		btrfs_add_ordered_extent(BTRFS_I(inode), file_offset,
+					 disk_bytenr, num_bytes, disk_num_bytes,
+					 type);
+	}
+}
+
+void btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
+				u64 post)
+{
+	struct inode *inode = ordered->inode;
+	struct btrfs_ordered_inode_tree *tree = &BTRFS_I(inode)->ordered_tree;
+	struct rb_node *node;
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+
+	spin_lock_irq(&tree->lock);
+	/* remove from tree once */
+	node = &ordered->rb_node;
+	rb_erase(node, &tree->tree);
+	RB_CLEAR_NODE(node);
+	if (tree->last == node)
+		tree->last = NULL;
+
+	ordered->file_offset += pre;
+	ordered->disk_bytenr += pre;
+	ordered->num_bytes -= (pre + post);
+	ordered->disk_num_bytes -= (pre + post);
+	ordered->bytes_left -= (pre + post);
+
+	/* re-insert the node */
+	node = tree_insert(&tree->tree, ordered->file_offset,
+			   &ordered->rb_node);
+	if (node)
+		btrfs_panic(fs_info, -EEXIST,
+				"inconsistency in ordered tree at offset %llu",
+				ordered->file_offset);
+
+	spin_unlock_irq(&tree->lock);
+
+	if (pre)
+		clone_ordered_extent(ordered, 0, pre);
+	if (post)
+		clone_ordered_extent(ordered, pre + ordered->disk_num_bytes, post);
+}
+
 int __init ordered_data_init(void)
 {
 	btrfs_ordered_extent_cache = kmem_cache_create("btrfs_ordered_extent",
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index c3a2325e64a4..e346b03bd66a 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -193,6 +193,8 @@ void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr,
 void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start,
 					u64 end,
 					struct extent_state **cached_state);
+void btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre,
+				u64 post);
 int __init ordered_data_init(void);
 void __cold ordered_data_exit(void);
 
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 24/41] btrfs: extend btrfs_rmap_block for specifying a device
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (21 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 23/41] btrfs: split ordered extent when bio is sent Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 25/41] btrfs: use ZONE_APPEND write for ZONED btrfs Naohiro Aota
                     ` (17 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

btrfs_rmap_block currently reverse-map the physical address on all devices
to logical addresses. This commit extends the function to match to a
specified device. You can still query all devices by specifying NULL as a
device.

This commit also exporet the function for later use.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c | 23 ++++++++++++++++++-----
 fs/btrfs/block-group.h |  3 +++
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 2241d04ad4aa..d39fa80d3d90 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1655,9 +1655,9 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
  * Used primarily to exclude those portions of a block group that contain super
  * block copies.
  */
-EXPORT_FOR_TESTS
-int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
-		     u64 physical, u64 **logical, int *naddrs, int *stripe_len)
+int __btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
+		       struct block_device *bdev, u64 physical, u64 **logical,
+		       int *naddrs, int *stripe_len)
 {
 	struct extent_map *em;
 	struct map_lookup *map;
@@ -1675,6 +1675,7 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 	map = em->map_lookup;
 	data_stripe_length = em->orig_block_len;
 	io_stripe_size = map->stripe_len;
+	chunk_start = em->start;
 
 	/* For RAID5/6 adjust to a full IO stripe length */
 	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
@@ -1689,14 +1690,18 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 	for (i = 0; i < map->num_stripes; i++) {
 		bool already_inserted = false;
 		u64 stripe_nr;
+		u64 offset;
 		int j;
 
 		if (!in_range(physical, map->stripes[i].physical,
 			      data_stripe_length))
 			continue;
 
+		if (bdev && map->stripes[i].dev->bdev != bdev)
+			continue;
+
 		stripe_nr = physical - map->stripes[i].physical;
-		stripe_nr = div64_u64(stripe_nr, map->stripe_len);
+		stripe_nr = div64_u64_rem(stripe_nr, map->stripe_len, &offset);
 
 		if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
 			stripe_nr = stripe_nr * map->num_stripes + i;
@@ -1710,7 +1715,7 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 		 * instead of map->stripe_len
 		 */
 
-		bytenr = chunk_start + stripe_nr * io_stripe_size;
+		bytenr = chunk_start + stripe_nr * io_stripe_size + offset;
 
 		/* Ensure we don't add duplicate addresses */
 		for (j = 0; j < nr; j++) {
@@ -1732,6 +1737,14 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
 	return ret;
 }
 
+EXPORT_FOR_TESTS
+int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
+		     u64 physical, u64 **logical, int *naddrs, int *stripe_len)
+{
+	return __btrfs_rmap_block(fs_info, chunk_start, NULL, physical, logical,
+				  naddrs, stripe_len);
+}
+
 static int exclude_super_stripes(struct btrfs_block_group *cache)
 {
 	struct btrfs_fs_info *fs_info = cache->fs_info;
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 5be47f4bfea7..401e9bcefaec 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -275,6 +275,9 @@ void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
 int btrfs_free_block_groups(struct btrfs_fs_info *info);
+int __btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
+		       struct block_device *bdev, u64 physical, u64 **logical,
+		       int *naddrs, int *stripe_len);
 
 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
 {
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 25/41] btrfs: use ZONE_APPEND write for ZONED btrfs
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (22 preceding siblings ...)
  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   ` 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
                     ` (16 subsequent siblings)
  40 siblings, 1 reply; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This commit enables zone append writing for zoned btrfs. Three parts are
necessary to enable it. First, it modifies bio to use REQ_OP_ZONE_APPEND in
btrfs_submit_bio_hook() and adjust the bi_sector to point the beginning of
the zone.

Second, it records returned physical address (and disk/partno) to
the ordered extent in end_bio_extent_writepage().

Finally, it rewrites logical addresses of the extent mapping and checksum
data according to the physical address (using __btrfs_rmap_block). If the
returned address match to the originaly allocated address, we can skip the
rewriting process.

[Johannes] fixed bvec handling
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/extent_io.c    | 12 +++++++-
 fs/btrfs/inode.c        |  6 +++-
 fs/btrfs/ordered-data.c |  3 ++
 fs/btrfs/ordered-data.h |  4 +++
 fs/btrfs/volumes.c      |  9 ++++++
 fs/btrfs/zoned.c        | 68 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h        |  9 ++++++
 7 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 5ee94a2ffa22..bbcdc8dfbd45 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2743,6 +2743,7 @@ static void end_bio_extent_writepage(struct bio *bio)
 	u64 start;
 	u64 end;
 	struct bvec_iter_all iter_all;
+	bool first_bvec = true;
 
 	ASSERT(!bio_flagged(bio, BIO_CLONED));
 	bio_for_each_segment_all(bvec, bio, iter_all) {
@@ -2769,6 +2770,11 @@ static void end_bio_extent_writepage(struct bio *bio)
 		start = page_offset(page);
 		end = start + bvec->bv_offset + bvec->bv_len - 1;
 
+		if (first_bvec) {
+			btrfs_record_physical_zoned(inode, start, bio);
+			first_bvec = false;
+		}
+
 		end_extent_writepage(page, error, start, end);
 		end_page_writeback(page);
 	}
@@ -3531,6 +3537,7 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
 	size_t blocksize;
 	int ret = 0;
 	int nr = 0;
+	int opf = REQ_OP_WRITE;
 	const unsigned int write_flags = wbc_to_write_flags(wbc);
 	bool compressed;
 
@@ -3543,6 +3550,9 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
 		return 1;
 	}
 
+	if (btrfs_fs_incompat(inode->root->fs_info, ZONED))
+		opf = REQ_OP_ZONE_APPEND;
+
 	/*
 	 * we don't want to touch the inode after unlocking the page,
 	 * so we update the mapping writeback index now
@@ -3603,7 +3613,7 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
 			       page->index, cur, end);
 		}
 
-		ret = submit_extent_page(REQ_OP_WRITE | write_flags, wbc,
+		ret = submit_extent_page(opf | write_flags, wbc,
 					 page, offset, iosize, pg_offset,
 					 &epd->bio,
 					 end_bio_extent_writepage,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4bc975eafbd8..b5fdc93b319f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -51,6 +51,7 @@
 #include "delalloc-space.h"
 #include "block-group.h"
 #include "space-info.h"
+#include "zoned.h"
 
 struct btrfs_iget_args {
 	u64 ino;
@@ -2279,7 +2280,7 @@ blk_status_t btrfs_submit_data_bio(struct inode *inode, struct bio *bio,
 			goto out;
 	}
 
-	if (bio_op(bio) != REQ_OP_WRITE) {
+	if (btrfs_op(bio) != BTRFS_MAP_WRITE) {
 		ret = btrfs_bio_wq_end_io(fs_info, bio, metadata);
 		if (ret)
 			goto out;
@@ -2674,6 +2675,9 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
 	bool clear_reserved_extent = true;
 	unsigned int clear_bits;
 
+	if (ordered_extent->disk)
+		btrfs_rewrite_logical_zoned(ordered_extent);
+
 	start = ordered_extent->file_offset;
 	end = start + ordered_extent->num_bytes - 1;
 
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 7cd22cb07f26..b32cdbfd408d 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -199,6 +199,9 @@ static int __btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset
 	entry->compress_type = compress_type;
 	entry->truncated_len = (u64)-1;
 	entry->qgroup_rsv = ret;
+	entry->physical = (u64)-1;
+	entry->disk = NULL;
+	entry->partno = (u8)-1;
 	if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
 		set_bit(type, &entry->flags);
 
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index e346b03bd66a..1d5a8dc00373 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -127,6 +127,10 @@ struct btrfs_ordered_extent {
 	struct completion completion;
 	struct btrfs_work flush_work;
 	struct list_head work_list;
+
+	u64 physical;
+	struct gendisk *disk;
+	u8 partno;
 };
 
 /*
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 44ef7b2fb46c..924ba96dc8fa 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6500,6 +6500,15 @@ static void submit_stripe_bio(struct btrfs_bio *bbio, struct bio *bio,
 	btrfs_io_bio(bio)->device = dev;
 	bio->bi_end_io = btrfs_end_bio;
 	bio->bi_iter.bi_sector = physical >> 9;
+	/*
+	 * For zone append writing, bi_sector must point the beginning of the
+	 * zone
+	 */
+	if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+		u64 zone_start = round_down(physical, fs_info->zone_size);
+
+		bio->bi_iter.bi_sector = zone_start >> SECTOR_SHIFT;
+	}
 	btrfs_debug_in_rcu(fs_info,
 	"btrfs_map_bio: rw %d 0x%x, sector=%llu, dev=%lu (%s id %llu), size=%u",
 		bio_op(bio), bio->bi_opf, (u64)bio->bi_iter.bi_sector,
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 88b45af60e4f..9e1056e2c2c8 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1054,3 +1054,71 @@ void btrfs_free_redirty_list(struct btrfs_transaction *trans)
 	}
 	spin_unlock(&trans->releasing_ebs_lock);
 }
+
+void btrfs_record_physical_zoned(struct inode *inode, u64 file_offset,
+				 struct bio *bio)
+{
+	struct btrfs_ordered_extent *ordered;
+	u64 physical = (u64)bio->bi_iter.bi_sector << SECTOR_SHIFT;
+
+	if (bio_op(bio) != REQ_OP_ZONE_APPEND)
+		return;
+
+	ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode), file_offset);
+	if (WARN_ON(!ordered))
+		return;
+
+	ordered->physical = physical;
+	ordered->disk = bio->bi_disk;
+	ordered->partno = bio->bi_partno;
+
+	btrfs_put_ordered_extent(ordered);
+}
+
+void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered)
+{
+	struct extent_map_tree *em_tree;
+	struct extent_map *em;
+	struct inode *inode = ordered->inode;
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+	struct btrfs_ordered_sum *sum;
+	struct block_device *bdev;
+	u64 orig_logical = ordered->disk_bytenr;
+	u64 *logical = NULL;
+	int nr, stripe_len;
+
+	bdev = bdget_disk(ordered->disk, ordered->partno);
+	if (WARN_ON(!bdev))
+		return;
+
+	if (WARN_ON(__btrfs_rmap_block(fs_info, orig_logical, bdev,
+				       ordered->physical, &logical, &nr,
+				       &stripe_len)))
+		goto out;
+
+	WARN_ON(nr != 1);
+
+	if (orig_logical == *logical)
+		goto out;
+
+	ordered->disk_bytenr = *logical;
+
+	em_tree = &BTRFS_I(inode)->extent_tree;
+	write_lock(&em_tree->lock);
+	em = search_extent_mapping(em_tree, ordered->file_offset,
+				   ordered->num_bytes);
+	em->block_start = *logical;
+	free_extent_map(em);
+	write_unlock(&em_tree->lock);
+
+	list_for_each_entry(sum, &ordered->list, list) {
+		if (*logical < orig_logical)
+			sum->bytenr -= orig_logical - *logical;
+		else
+			sum->bytenr += *logical - orig_logical;
+	}
+
+out:
+	kfree(logical);
+	bdput(bdev);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 32446135e882..f6263a893a07 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -50,6 +50,9 @@ void btrfs_calc_zone_unusable(struct btrfs_block_group *cache);
 void btrfs_redirty_list_add(struct btrfs_transaction *trans,
 			    struct extent_buffer *eb);
 void btrfs_free_redirty_list(struct btrfs_transaction *trans);
+void btrfs_record_physical_zoned(struct inode *inode, u64 file_offset,
+				 struct bio *bio);
+void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -119,6 +122,12 @@ static inline void btrfs_calc_zone_unusable(struct btrfs_block_group *cache) { }
 static inline void btrfs_redirty_list_add(struct btrfs_transaction *trans,
 					  struct extent_buffer *eb) { }
 static inline void btrfs_free_redirty_list(struct btrfs_transaction *trans) { }
+static inline void btrfs_record_physical_zoned(struct inode *inode,
+					       u64 file_offset, struct bio *bio)
+{
+}
+static inline void
+btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered) { }
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 26/41] btrfs: enable zone append writing for direct IO
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (23 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 25/41] btrfs: use ZONE_APPEND write for ZONED btrfs Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 27/41] btrfs: introduce dedicated data write path for ZONED mode Naohiro Aota
                     ` (15 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This commit enables zone append writing as same as in buffered write.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/inode.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index b5fdc93b319f..37d85c062f3a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7422,6 +7422,11 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 	       current->journal_info == BTRFS_DIO_SYNC_STUB);
 	current->journal_info = NULL;
 
+	if (write && fs_info->max_zone_append_size) {
+		length = min_t(u64, length, fs_info->max_zone_append_size);
+		len = length;
+	}
+
 	if (!write)
 		len = min_t(u64, len, fs_info->sectorsize);
 
@@ -7777,6 +7782,8 @@ static void btrfs_end_dio_bio(struct bio *bio)
 	if (err)
 		dip->dio_bio->bi_status = err;
 
+	btrfs_record_physical_zoned(dip->inode, dip->logical_offset, bio);
+
 	bio_put(bio);
 	btrfs_dio_private_put(dip);
 }
@@ -7786,7 +7793,8 @@ static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_dio_private *dip = bio->bi_private;
-	bool write = bio_op(bio) == REQ_OP_WRITE;
+	bool write = bio_op(bio) == REQ_OP_WRITE ||
+		     bio_op(bio) == REQ_OP_ZONE_APPEND;
 	blk_status_t ret;
 
 	/* Check btrfs_submit_bio_hook() for rules about async submit. */
@@ -7931,6 +7939,12 @@ static blk_qc_t btrfs_submit_direct(struct inode *inode, struct iomap *iomap,
 		bio->bi_end_io = btrfs_end_dio_bio;
 		btrfs_io_bio(bio)->logical = file_offset;
 
+		if (write && btrfs_fs_incompat(fs_info, ZONED) &&
+		    fs_info->max_zone_append_size) {
+			bio->bi_opf &= ~REQ_OP_MASK;
+			bio->bi_opf |= REQ_OP_ZONE_APPEND;
+		}
+
 		ASSERT(submit_len >= clone_len);
 		submit_len -= clone_len;
 
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 27/41] btrfs: introduce dedicated data write path for ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (24 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 26/41] btrfs: enable zone append writing for direct IO Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 28/41] btrfs: serialize meta IOs on " Naohiro Aota
                     ` (14 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

If more than one IO is issued for one file extent, these IO can be written
in a separate region on a device. Since we cannot map one file extent to
such a separate area, we need to follow the "one IO == one ordered extent"
rule.

Normal (buffered, uncompressed, not pre-allocated) write path (=
cow_file_range()) sometime does not follow the rule. It can write a part of
an ordered extent when specified a region to write e.g., called from
fdatasync().

This commit introduces a dedicated (uncompressed buffered) data write path
for ZONED mode. This write path CoW the region and write the region at
once.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/inode.c | 34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 37d85c062f3a..46eba6c7792b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1350,6 +1350,29 @@ static int cow_file_range_async(struct btrfs_inode *inode,
 	return 0;
 }
 
+static noinline int run_delalloc_zoned(struct btrfs_inode *inode,
+				       struct page *locked_page, u64 start,
+				       u64 end, int *page_started,
+				       unsigned long *nr_written)
+{
+	int ret;
+
+	ret = cow_file_range(inode, locked_page, start, end,
+			     page_started, nr_written, 0);
+	if (ret)
+		return ret;
+
+	if (*page_started)
+		return 0;
+
+	__set_page_dirty_nobuffers(locked_page);
+	account_page_redirty(locked_page);
+	extent_write_locked_range(&inode->vfs_inode, start, end, WB_SYNC_ALL);
+	*page_started = 1;
+
+	return 0;
+}
+
 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info,
 					u64 bytenr, u64 num_bytes)
 {
@@ -1820,17 +1843,24 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page
 {
 	int ret;
 	int force_cow = need_force_cow(inode, start, end);
+	int do_compress = inode_can_compress(inode) &&
+		inode_need_compress(inode, start, end);
+	bool zoned = btrfs_fs_incompat(inode->root->fs_info, ZONED);
 
 	if (inode->flags & BTRFS_INODE_NODATACOW && !force_cow) {
+		ASSERT(!zoned);
 		ret = run_delalloc_nocow(inode, locked_page, start, end,
 					 page_started, 1, nr_written);
 	} else if (inode->flags & BTRFS_INODE_PREALLOC && !force_cow) {
+		ASSERT(!zoned);
 		ret = run_delalloc_nocow(inode, locked_page, start, end,
 					 page_started, 0, nr_written);
-	} else if (!inode_can_compress(inode) ||
-		   !inode_need_compress(inode, start, end)) {
+	} else if (!do_compress && !zoned) {
 		ret = cow_file_range(inode, locked_page, start, end,
 				     page_started, nr_written, 1);
+	} else if (!do_compress && zoned) {
+		ret = run_delalloc_zoned(inode, locked_page, start, end,
+					 page_started, nr_written);
 	} else {
 		set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &inode->runtime_flags);
 		ret = cow_file_range_async(inode, wbc, locked_page, start, end,
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 28/41] btrfs: serialize meta IOs on ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (25 preceding siblings ...)
  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   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 29/41] btrfs: wait existing extents before truncating Naohiro Aota
                     ` (13 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

We cannot use zone append writing for metadata, because the B-tree nodes
have references to each other using the logical address. Without knowing
the address in advance, we cannot construct the tree in the first place.
Thus, we need to serialize write IOs for metadata.

We cannot add mutex around allocation and submit because metadata blocks
are allocated in an earlier stage to build up B-trees.

Thus, this commit add zoned_meta_io_lock and hold it during metadata IO
submission in btree_write_cache_pages() to serialize IOs. Furthermore, this
commit add per-block group metadata IO submission pointer
"meta_write_pointer" to ensure sequential writing, which can be caused when
writing back blocks in a not finished transaction.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.h |  1 +
 fs/btrfs/ctree.h       |  2 ++
 fs/btrfs/disk-io.c     |  1 +
 fs/btrfs/extent_io.c   | 27 ++++++++++++++++++++++-
 fs/btrfs/zoned.c       | 50 ++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h       | 31 ++++++++++++++++++++++++++
 6 files changed, 111 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 401e9bcefaec..b2a8a3beceac 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -190,6 +190,7 @@ struct btrfs_block_group {
 	 */
 	u64 alloc_offset;
 	u64 zone_unusable;
+	u64 meta_write_pointer;
 };
 
 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e6f0fe1920e9..d021bc4a92cd 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -953,6 +953,8 @@ struct btrfs_fs_info {
 	/* Type of exclusive operation running */
 	unsigned long exclusive_operation;
 
+	struct mutex zoned_meta_io_lock;
+
 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
 	spinlock_t ref_verify_lock;
 	struct rb_root block_tree;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index c872f051b0a5..87c978fecaa2 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2652,6 +2652,7 @@ void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
 	mutex_init(&fs_info->delete_unused_bgs_mutex);
 	mutex_init(&fs_info->reloc_mutex);
 	mutex_init(&fs_info->delalloc_root_mutex);
+	mutex_init(&fs_info->zoned_meta_io_lock);
 	seqlock_init(&fs_info->profiles_lock);
 
 	INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index bbcdc8dfbd45..ed6a9fce016d 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -25,6 +25,7 @@
 #include "backref.h"
 #include "disk-io.h"
 #include "zoned.h"
+#include "block-group.h"
 
 static struct kmem_cache *extent_state_cache;
 static struct kmem_cache *extent_buffer_cache;
@@ -4001,6 +4002,7 @@ int btree_write_cache_pages(struct address_space *mapping,
 				   struct writeback_control *wbc)
 {
 	struct extent_buffer *eb, *prev_eb = NULL;
+	struct btrfs_block_group *cache = NULL;
 	struct extent_page_data epd = {
 		.bio = NULL,
 		.extent_locked = 0,
@@ -4035,6 +4037,7 @@ int btree_write_cache_pages(struct address_space *mapping,
 		tag = PAGECACHE_TAG_TOWRITE;
 	else
 		tag = PAGECACHE_TAG_DIRTY;
+	btrfs_zoned_meta_io_lock(fs_info);
 retry:
 	if (wbc->sync_mode == WB_SYNC_ALL)
 		tag_pages_for_writeback(mapping, index, end);
@@ -4077,12 +4080,30 @@ int btree_write_cache_pages(struct address_space *mapping,
 			if (!ret)
 				continue;
 
+			if (!btrfs_check_meta_write_pointer(fs_info, eb,
+							    &cache)) {
+				/*
+				 * If for_sync, this hole will be filled with
+				 * trasnsaction commit.
+				 */
+				if (wbc->sync_mode == WB_SYNC_ALL &&
+				    !wbc->for_sync)
+					ret = -EAGAIN;
+				else
+					ret = 0;
+				done = 1;
+				free_extent_buffer(eb);
+				break;
+			}
+
 			prev_eb = eb;
 			ret = lock_extent_buffer_for_io(eb, &epd);
 			if (!ret) {
+				btrfs_revert_meta_write_pointer(cache, eb);
 				free_extent_buffer(eb);
 				continue;
 			} else if (ret < 0) {
+				btrfs_revert_meta_write_pointer(cache, eb);
 				done = 1;
 				free_extent_buffer(eb);
 				break;
@@ -4115,10 +4136,12 @@ int btree_write_cache_pages(struct address_space *mapping,
 		index = 0;
 		goto retry;
 	}
+	if (cache)
+		btrfs_put_block_group(cache);
 	ASSERT(ret <= 0);
 	if (ret < 0) {
 		end_write_bio(&epd, ret);
-		return ret;
+		goto out;
 	}
 	/*
 	 * If something went wrong, don't allow any metadata write bio to be
@@ -4153,6 +4176,8 @@ int btree_write_cache_pages(struct address_space *mapping,
 		ret = -EROFS;
 		end_write_bio(&epd, ret);
 	}
+out:
+	btrfs_zoned_meta_io_unlock(fs_info);
 	return ret;
 }
 
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 9e1056e2c2c8..57bd6dbd8f45 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -991,6 +991,9 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 		ret = -EIO;
 	}
 
+	if (!ret)
+		cache->meta_write_pointer = cache->alloc_offset + cache->start;
+
 	kfree(alloc_offsets);
 	free_extent_map(em);
 
@@ -1122,3 +1125,50 @@ void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered)
 	kfree(logical);
 	bdput(bdev);
 }
+
+bool btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
+				    struct extent_buffer *eb,
+				    struct btrfs_block_group **cache_ret)
+{
+	struct btrfs_block_group *cache;
+
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return true;
+
+	cache = *cache_ret;
+
+	if (cache && (eb->start < cache->start ||
+		      cache->start + cache->length <= eb->start)) {
+		btrfs_put_block_group(cache);
+		cache = NULL;
+		*cache_ret = NULL;
+	}
+
+	if (!cache)
+		cache = btrfs_lookup_block_group(fs_info, eb->start);
+
+	if (cache) {
+		*cache_ret = cache;
+
+		if (cache->meta_write_pointer != eb->start) {
+			btrfs_put_block_group(cache);
+			cache = NULL;
+			*cache_ret = NULL;
+			return false;
+		}
+
+		cache->meta_write_pointer = eb->start + eb->len;
+	}
+
+	return true;
+}
+
+void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
+				     struct extent_buffer *eb)
+{
+	if (!btrfs_fs_incompat(eb->fs_info, ZONED) || !cache)
+		return;
+
+	ASSERT(cache->meta_write_pointer == eb->start + eb->len);
+	cache->meta_write_pointer = eb->start;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index f6263a893a07..fc8012ebcc36 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -53,6 +53,11 @@ void btrfs_free_redirty_list(struct btrfs_transaction *trans);
 void btrfs_record_physical_zoned(struct inode *inode, u64 file_offset,
 				 struct bio *bio);
 void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered);
+bool btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
+				    struct extent_buffer *eb,
+				    struct btrfs_block_group **cache_ret);
+void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
+				     struct extent_buffer *eb);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -128,6 +133,18 @@ static inline void btrfs_record_physical_zoned(struct inode *inode,
 }
 static inline void
 btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered) { }
+static inline bool
+btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
+			       struct extent_buffer *eb,
+			       struct btrfs_block_group **cache_ret)
+{
+	return true;
+}
+static inline void
+btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
+				struct extent_buffer *eb)
+{
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
@@ -230,4 +247,18 @@ static inline bool btrfs_can_zone_reset(struct btrfs_device *device,
 	return true;
 }
 
+static inline void btrfs_zoned_meta_io_lock(struct btrfs_fs_info *fs_info)
+{
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return;
+	mutex_lock(&fs_info->zoned_meta_io_lock);
+}
+
+static inline void btrfs_zoned_meta_io_unlock(struct btrfs_fs_info *fs_info)
+{
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return;
+	mutex_unlock(&fs_info->zoned_meta_io_lock);
+}
+
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 29/41] btrfs: wait existing extents before truncating
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (26 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 28/41] btrfs: serialize meta IOs on " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 30/41] btrfs: avoid async metadata checksum on ZONED mode Naohiro Aota
                     ` (12 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik

When truncating a file, file buffers which have already been allocated but
not yet written may be truncated.  Truncating these buffers could cause
breakage of a sequential write pattern in a block group if the truncated
blocks are for example followed by blocks allocated to another file. To
avoid this problem, always wait for write out of all unwritten buffers
before proceeding with the truncate execution.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/inode.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 46eba6c7792b..40704b61f582 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4953,6 +4953,16 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 		btrfs_drew_write_unlock(&root->snapshot_lock);
 		btrfs_end_transaction(trans);
 	} else {
+		struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+
+		if (btrfs_fs_incompat(fs_info, ZONED)) {
+			ret = btrfs_wait_ordered_range(
+				inode,
+				ALIGN(newsize, fs_info->sectorsize),
+				(u64)-1);
+			if (ret)
+				return ret;
+		}
 
 		/*
 		 * We're truncating a file that used to have good data down to
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 30/41] btrfs: avoid async metadata checksum on ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (27 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 29/41] btrfs: wait existing extents before truncating Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 31/41] btrfs: mark block groups to copy for device-replace Naohiro Aota
                     ` (11 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

In ZONED, btrfs uses per-FS zoned_meta_io_lock to serialize the metadata
write IOs.

Even with these serialization, write bios sent from btree_write_cache_pages
can be reordered by async checksum workers as these workers are per CPU and
not per zone.

To preserve write BIO ordering, we can disable async metadata checksum on
ZONED.  This does not result in lower performance with HDDs as a single CPU
core is fast enough to do checksum for a single zone write stream with the
maximum possible bandwidth of the device. If multiple zones are being
written simultaneously, HDD seek overhead lowers the achievable maximum
bandwidth, resulting again in a per zone checksum serialization not
affecting performance.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/disk-io.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 87c978fecaa2..5ce5b18f9dc4 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -813,6 +813,8 @@ static blk_status_t btree_submit_bio_start(void *private_data, struct bio *bio,
 static int check_async_write(struct btrfs_fs_info *fs_info,
 			     struct btrfs_inode *bi)
 {
+	if (btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
 	if (atomic_read(&bi->sync_writers))
 		return 0;
 	if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 31/41] btrfs: mark block groups to copy for device-replace
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (28 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 30/41] btrfs: avoid async metadata checksum on ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 32/41] btrfs: implement cloning for ZONED device-replace Naohiro Aota
                     ` (10 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is the 1/4 patch to support device-replace in ZONED mode.

We have two types of I/Os during the device-replace process. One is an I/O
to "copy" (by the scrub functions) all the device extents on the source
device to the destination device.  The other one is an I/O to "clone" (by
handle_ops_on_dev_replace()) new incoming write I/Os from users to the
source device into the target device.

Cloning incoming I/Os can break the sequential write rule in the target
device. When writing is mapped in the middle of a block group, the I/O is
directed in the middle of a target device zone, which breaks the sequential
write rule.

However, the cloning function cannot be merely disabled since incoming I/Os
targeting already copied device extents must be cloned so that the I/O is
executed on the target device.

We cannot use dev_replace->cursor_{left,right} to determine whether bio is
going to not yet copied region.  Since we have a time gap between finishing
btrfs_scrub_dev() and rewriting the mapping tree in
btrfs_dev_replace_finishing(), we can have a newly allocated device extent
which is never cloned nor copied.

So the point is to copy only already existing device extents. This patch
introduces mark_block_group_to_copy() to mark existing block groups as a
target of copying. Then, handle_ops_on_dev_replace() and dev-replace can
check the flag to do their job.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.h |   1 +
 fs/btrfs/dev-replace.c | 175 +++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/dev-replace.h |   3 +
 fs/btrfs/scrub.c       |  17 ++++
 4 files changed, 196 insertions(+)

diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index b2a8a3beceac..e91123495d68 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -95,6 +95,7 @@ struct btrfs_block_group {
 	unsigned int iref:1;
 	unsigned int has_caching_ctl:1;
 	unsigned int removed:1;
+	unsigned int to_copy:1;
 
 	int disk_cache_state;
 
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 5e3554482af1..e86aff38aea4 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -22,6 +22,7 @@
 #include "dev-replace.h"
 #include "sysfs.h"
 #include "zoned.h"
+#include "block-group.h"
 
 /*
  * Device replace overview
@@ -437,6 +438,176 @@ static char* btrfs_dev_name(struct btrfs_device *device)
 		return rcu_str_deref(device->name);
 }
 
+static int mark_block_group_to_copy(struct btrfs_fs_info *fs_info,
+				    struct btrfs_device *src_dev)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_key found_key;
+	struct btrfs_root *root = fs_info->dev_root;
+	struct btrfs_dev_extent *dev_extent = NULL;
+	struct btrfs_block_group *cache;
+	struct extent_buffer *l;
+	struct btrfs_trans_handle *trans;
+	int slot;
+	int ret = 0;
+	u64 chunk_offset, length;
+
+	/* Do not use "to_copy" on non-ZONED for now */
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
+	mutex_lock(&fs_info->chunk_mutex);
+
+	/* ensulre we don't have pending new block group */
+	while (fs_info->running_transaction &&
+	       !list_empty(&fs_info->running_transaction->dev_update_list)) {
+		mutex_unlock(&fs_info->chunk_mutex);
+		trans = btrfs_attach_transaction(root);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			mutex_lock(&fs_info->chunk_mutex);
+			if (ret == -ENOENT)
+				continue;
+			else
+				goto out;
+		}
+
+		ret = btrfs_commit_transaction(trans);
+		mutex_lock(&fs_info->chunk_mutex);
+		if (ret)
+			goto out;
+	}
+
+	path = btrfs_alloc_path();
+	if (!path) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	path->reada = READA_FORWARD;
+	path->search_commit_root = 1;
+	path->skip_locking = 1;
+
+	key.objectid = src_dev->devid;
+	key.offset = 0ull;
+	key.type = BTRFS_DEV_EXTENT_KEY;
+
+	while (1) {
+		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+		if (ret < 0)
+			break;
+		if (ret > 0) {
+			if (path->slots[0] >=
+			    btrfs_header_nritems(path->nodes[0])) {
+				ret = btrfs_next_leaf(root, path);
+				if (ret < 0)
+					break;
+				if (ret > 0) {
+					ret = 0;
+					break;
+				}
+			} else {
+				ret = 0;
+			}
+		}
+
+		l = path->nodes[0];
+		slot = path->slots[0];
+
+		btrfs_item_key_to_cpu(l, &found_key, slot);
+
+		if (found_key.objectid != src_dev->devid)
+			break;
+
+		if (found_key.type != BTRFS_DEV_EXTENT_KEY)
+			break;
+
+		if (found_key.offset < key.offset)
+			break;
+
+		dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
+		length = btrfs_dev_extent_length(l, dev_extent);
+
+		chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
+
+		cache = btrfs_lookup_block_group(fs_info, chunk_offset);
+		if (!cache)
+			goto skip;
+
+		spin_lock(&cache->lock);
+		cache->to_copy = 1;
+		spin_unlock(&cache->lock);
+
+		btrfs_put_block_group(cache);
+
+skip:
+		key.offset = found_key.offset + length;
+		btrfs_release_path(path);
+	}
+
+	btrfs_free_path(path);
+out:
+	mutex_unlock(&fs_info->chunk_mutex);
+
+	return ret;
+}
+
+bool btrfs_finish_block_group_to_copy(struct btrfs_device *srcdev,
+				      struct btrfs_block_group *cache,
+				      u64 physical)
+{
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	struct extent_map *em;
+	struct map_lookup *map;
+	u64 chunk_offset = cache->start;
+	int num_extents, cur_extent;
+	int i;
+
+	/* Do not use "to_copy" on non-ZONED for now */
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return true;
+
+	spin_lock(&cache->lock);
+	if (cache->removed) {
+		spin_unlock(&cache->lock);
+		return true;
+	}
+	spin_unlock(&cache->lock);
+
+	em = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
+	BUG_ON(IS_ERR(em));
+	map = em->map_lookup;
+
+	num_extents = cur_extent = 0;
+	for (i = 0; i < map->num_stripes; i++) {
+		/* we have more device extent to copy */
+		if (srcdev != map->stripes[i].dev)
+			continue;
+
+		num_extents++;
+		if (physical == map->stripes[i].physical)
+			cur_extent = i;
+	}
+
+	free_extent_map(em);
+
+	if (num_extents > 1 && cur_extent < num_extents - 1) {
+		/*
+		 * Has more stripes on this device. Keep this BG
+		 * readonly until we finish all the stripes.
+		 */
+		return false;
+	}
+
+	/* last stripe on this device */
+	spin_lock(&cache->lock);
+	cache->to_copy = 0;
+	spin_unlock(&cache->lock);
+
+	return true;
+}
+
 static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 		const char *tgtdev_name, u64 srcdevid, const char *srcdev_name,
 		int read_src)
@@ -478,6 +649,10 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
 	if (ret)
 		return ret;
 
+	ret = mark_block_group_to_copy(fs_info, src_device);
+	if (ret)
+		return ret;
+
 	down_write(&dev_replace->rwsem);
 	switch (dev_replace->replace_state) {
 	case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h
index 60b70dacc299..3911049a5f23 100644
--- a/fs/btrfs/dev-replace.h
+++ b/fs/btrfs/dev-replace.h
@@ -18,5 +18,8 @@ int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info);
 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info);
 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info);
 int __pure btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace);
+bool btrfs_finish_block_group_to_copy(struct btrfs_device *srcdev,
+				      struct btrfs_block_group *cache,
+				      u64 physical);
 
 #endif
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index aa1b36cf5c88..d0d7db3c8b0b 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3500,6 +3500,17 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 		if (!cache)
 			goto skip;
 
+
+		if (sctx->is_dev_replace && btrfs_fs_incompat(fs_info, ZONED)) {
+			spin_lock(&cache->lock);
+			if (!cache->to_copy) {
+				spin_unlock(&cache->lock);
+				ro_set = 0;
+				goto done;
+			}
+			spin_unlock(&cache->lock);
+		}
+
 		/*
 		 * Make sure that while we are scrubbing the corresponding block
 		 * group doesn't get its logical address and its device extents
@@ -3631,6 +3642,12 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 
 		scrub_pause_off(fs_info);
 
+		if (sctx->is_dev_replace &&
+		    !btrfs_finish_block_group_to_copy(dev_replace->srcdev,
+						      cache, found_key.offset))
+			ro_set = 0;
+
+done:
 		down_write(&dev_replace->rwsem);
 		dev_replace->cursor_left = dev_replace->cursor_right;
 		dev_replace->item_needs_writeback = 1;
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 32/41] btrfs: implement cloning for ZONED device-replace
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (29 preceding siblings ...)
  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   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 33/41] btrfs: implement copying " Naohiro Aota
                     ` (9 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is 2/4 patch to implement device-replace for ZONED mode.

On zoned mode, a block group must be either copied (from the source device
to the destination device) or cloned (to the both device).

This commit implements the cloning part. If a block group targeted by an IO
is marked to copy, we should not clone the IO to the destination device,
because the block group is eventually copied by the replace process.

This commit also handles cloning of device reset.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/extent-tree.c | 20 ++++++++++++++++++--
 fs/btrfs/volumes.c     | 33 +++++++++++++++++++++++++++++++--
 fs/btrfs/zoned.c       | 11 +++++++++++
 3 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c0e4a577c61c..f44faaf7aca2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -35,6 +35,7 @@
 #include "discard.h"
 #include "rcu-string.h"
 #include "zoned.h"
+#include "dev-replace.h"
 
 #undef SCRAMBLE_DELAYED_REFS
 
@@ -1336,6 +1337,8 @@ int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
 			u64 length = stripe->length;
 			u64 bytes;
 			struct request_queue *req_q;
+			struct btrfs_dev_replace *dev_replace =
+				&fs_info->dev_replace;
 
 			if (!stripe->dev->bdev) {
 				ASSERT(btrfs_test_opt(fs_info, DEGRADED));
@@ -1344,15 +1347,28 @@ int btrfs_discard_extent(struct btrfs_fs_info *fs_info, u64 bytenr,
 
 			req_q = bdev_get_queue(stripe->dev->bdev);
 			/* zone reset in ZONED mode */
-			if (btrfs_can_zone_reset(dev, physical, length))
+			if (btrfs_can_zone_reset(dev, physical, length)) {
 				ret = btrfs_reset_device_zone(dev, physical,
 							      length, &bytes);
-			else if (blk_queue_discard(req_q))
+				if (ret)
+					goto next;
+				if (!btrfs_dev_replace_is_ongoing(
+					    dev_replace) ||
+				    dev != dev_replace->srcdev)
+					goto next;
+
+				discarded_bytes += bytes;
+				/* send to replace target as well */
+				ret = btrfs_reset_device_zone(
+					dev_replace->tgtdev,
+					physical, length, &bytes);
+			} else if (blk_queue_discard(req_q))
 				ret = btrfs_issue_discard(dev->bdev, physical,
 							  length, &bytes);
 			else
 				continue;
 
+next:
 			if (!ret) {
 				discarded_bytes += bytes;
 			} else if (ret != -EOPNOTSUPP) {
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 924ba96dc8fa..af2ed4d3389f 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5965,9 +5965,29 @@ static int get_extra_mirror_from_replace(struct btrfs_fs_info *fs_info,
 	return ret;
 }
 
+static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical)
+{
+	struct btrfs_block_group *cache;
+	bool ret;
+
+	/* non-ZONED mode does not use "to_copy" flag */
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return false;
+
+	cache = btrfs_lookup_block_group(fs_info, logical);
+
+	spin_lock(&cache->lock);
+	ret = cache->to_copy;
+	spin_unlock(&cache->lock);
+
+	btrfs_put_block_group(cache);
+	return ret;
+}
+
 static void handle_ops_on_dev_replace(enum btrfs_map_op op,
 				      struct btrfs_bio **bbio_ret,
 				      struct btrfs_dev_replace *dev_replace,
+				      u64 logical,
 				      int *num_stripes_ret, int *max_errors_ret)
 {
 	struct btrfs_bio *bbio = *bbio_ret;
@@ -5980,6 +6000,15 @@ static void handle_ops_on_dev_replace(enum btrfs_map_op op,
 	if (op == BTRFS_MAP_WRITE) {
 		int index_where_to_add;
 
+		/*
+		 * a block group which have "to_copy" set will
+		 * eventually copied by dev-replace process. We can
+		 * avoid cloning IO here.
+		 */
+		if (is_block_group_to_copy(dev_replace->srcdev->fs_info,
+					   logical))
+			return;
+
 		/*
 		 * duplicate the write operations while the dev replace
 		 * procedure is running. Since the copying of the old disk to
@@ -6375,8 +6404,8 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 
 	if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
 	    need_full_stripe(op)) {
-		handle_ops_on_dev_replace(op, &bbio, dev_replace, &num_stripes,
-					  &max_errors);
+		handle_ops_on_dev_replace(op, &bbio, dev_replace, logical,
+					  &num_stripes, &max_errors);
 	}
 
 	*bbio_ret = bbio;
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 57bd6dbd8f45..f10cc5f49962 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -17,6 +17,7 @@
 #include "disk-io.h"
 #include "block-group.h"
 #include "transaction.h"
+#include "dev-replace.h"
 
 /* Maximum number of zones to report per blkdev_report_zones() call */
 #define BTRFS_REPORT_NR_ZONES   4096
@@ -892,6 +893,8 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 	for (i = 0; i < map->num_stripes; i++) {
 		bool is_sequential;
 		struct blk_zone zone;
+		struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
+		int dev_replace_is_ongoing = 0;
 
 		device = map->stripes[i].dev;
 		physical = map->stripes[i].physical;
@@ -918,6 +921,14 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
 		 */
 		btrfs_dev_clear_zone_empty(device, physical);
 
+		down_read(&dev_replace->rwsem);
+		dev_replace_is_ongoing =
+			btrfs_dev_replace_is_ongoing(dev_replace);
+		if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL)
+			btrfs_dev_clear_zone_empty(dev_replace->tgtdev,
+						   physical);
+		up_read(&dev_replace->rwsem);
+
 		/*
 		 * The group is mapped to a sequential zone. Get the zone write
 		 * pointer to determine the allocation offset within the zone.
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 33/41] btrfs: implement copying for ZONED device-replace
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (30 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 32/41] btrfs: implement cloning for ZONED device-replace Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 34/41] btrfs: support dev-replace in ZONED mode Naohiro Aota
                     ` (8 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is 3/4 patch to implement device-replace on ZONED mode.

This commit implement copying. So, it track the write pointer during device
replace process. Device-replace's copying is smart to copy only used
extents on source device, we have to fill the gap to honor the sequential
write rule in the target device.

Device-replace process in ZONED mode must copy or clone all the extents in
the source device exactly once.  So, we need to use to ensure allocations
started just before the dev-replace process to have their corresponding
extent information in the B-trees. finish_extent_writes_for_zoned()
implements that functionality, which basically is the removed code in the
commit 042528f8d840 ("Btrfs: fix block group remaining RO forever after
error during device replace").

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/scrub.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.c | 12 +++++++
 fs/btrfs/zoned.h |  7 ++++
 3 files changed, 105 insertions(+)

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index d0d7db3c8b0b..65e460670160 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -169,6 +169,7 @@ struct scrub_ctx {
 	int			pages_per_rd_bio;
 
 	int			is_dev_replace;
+	u64			write_pointer;
 
 	struct scrub_bio        *wr_curr_bio;
 	struct mutex            wr_lock;
@@ -1623,6 +1624,25 @@ static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
 	return scrub_add_page_to_wr_bio(sblock->sctx, spage);
 }
 
+static int fill_writer_pointer_gap(struct scrub_ctx *sctx, u64 physical)
+{
+	int ret = 0;
+	u64 length;
+
+	if (!btrfs_fs_incompat(sctx->fs_info, ZONED))
+		return 0;
+
+	if (sctx->write_pointer < physical) {
+		length = physical - sctx->write_pointer;
+
+		ret = btrfs_zoned_issue_zeroout(sctx->wr_tgtdev,
+						sctx->write_pointer, length);
+		if (!ret)
+			sctx->write_pointer = physical;
+	}
+	return ret;
+}
+
 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
 				    struct scrub_page *spage)
 {
@@ -1645,6 +1665,13 @@ static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
 	if (sbio->page_count == 0) {
 		struct bio *bio;
 
+		ret = fill_writer_pointer_gap(sctx,
+					      spage->physical_for_dev_replace);
+		if (ret) {
+			mutex_unlock(&sctx->wr_lock);
+			return ret;
+		}
+
 		sbio->physical = spage->physical_for_dev_replace;
 		sbio->logical = spage->logical;
 		sbio->dev = sctx->wr_tgtdev;
@@ -1706,6 +1733,10 @@ static void scrub_wr_submit(struct scrub_ctx *sctx)
 	 * doubled the write performance on spinning disks when measured
 	 * with Linux 3.5 */
 	btrfsic_submit_bio(sbio->bio);
+
+	if (btrfs_fs_incompat(sctx->fs_info, ZONED))
+		sctx->write_pointer = sbio->physical +
+			sbio->page_count * PAGE_SIZE;
 }
 
 static void scrub_wr_bio_end_io(struct bio *bio)
@@ -2973,6 +3004,21 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
 	return ret < 0 ? ret : 0;
 }
 
+static void sync_replace_for_zoned(struct scrub_ctx *sctx)
+{
+	if (!btrfs_fs_incompat(sctx->fs_info, ZONED))
+		return;
+
+	sctx->flush_all_writes = true;
+	scrub_submit(sctx);
+	mutex_lock(&sctx->wr_lock);
+	scrub_wr_submit(sctx);
+	mutex_unlock(&sctx->wr_lock);
+
+	wait_event(sctx->list_wait,
+		   atomic_read(&sctx->bios_in_flight) == 0);
+}
+
 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 					   struct map_lookup *map,
 					   struct btrfs_device *scrub_dev,
@@ -3105,6 +3151,14 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 	 */
 	blk_start_plug(&plug);
 
+	if (sctx->is_dev_replace &&
+	    btrfs_dev_is_sequential(sctx->wr_tgtdev, physical)) {
+		mutex_lock(&sctx->wr_lock);
+		sctx->write_pointer = physical;
+		mutex_unlock(&sctx->wr_lock);
+		sctx->flush_all_writes = true;
+	}
+
 	/*
 	 * now find all extents for each stripe and scrub them
 	 */
@@ -3292,6 +3346,9 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 			if (ret)
 				goto out;
 
+			if (sctx->is_dev_replace)
+				sync_replace_for_zoned(sctx);
+
 			if (extent_logical + extent_len <
 			    key.objectid + bytes) {
 				if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
@@ -3414,6 +3471,25 @@ static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
 	return ret;
 }
 
+static int finish_extent_writes_for_zoned(struct btrfs_root *root,
+					  struct btrfs_block_group *cache)
+{
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	struct btrfs_trans_handle *trans;
+
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
+	btrfs_wait_block_group_reservations(cache);
+	btrfs_wait_nocow_writers(cache);
+	btrfs_wait_ordered_roots(fs_info, U64_MAX, cache->start, cache->length);
+
+	trans = btrfs_join_transaction(root);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
+	return btrfs_commit_transaction(trans);
+}
+
 static noinline_for_stack
 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 			   struct btrfs_device *scrub_dev, u64 start, u64 end)
@@ -3569,6 +3645,16 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 		 * group is not RO.
 		 */
 		ret = btrfs_inc_block_group_ro(cache, sctx->is_dev_replace);
+		if (!ret && sctx->is_dev_replace) {
+			ret = finish_extent_writes_for_zoned(root, cache);
+			if (ret) {
+				btrfs_dec_block_group_ro(cache);
+				scrub_pause_off(fs_info);
+				btrfs_put_block_group(cache);
+				break;
+			}
+		}
+
 		if (ret == 0) {
 			ro_set = 1;
 		} else if (ret == -ENOSPC && !sctx->is_dev_replace) {
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index f10cc5f49962..7ff2a590c93f 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1183,3 +1183,15 @@ void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
 	ASSERT(cache->meta_write_pointer == eb->start + eb->len);
 	cache->meta_write_pointer = eb->start;
 }
+
+int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical,
+			      u64 length)
+{
+	if (!btrfs_dev_is_sequential(device, physical))
+		return -EOPNOTSUPP;
+
+	return blkdev_issue_zeroout(device->bdev,
+				    physical >> SECTOR_SHIFT,
+				    length >> SECTOR_SHIFT,
+				    GFP_NOFS, 0);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index fc8012ebcc36..d5b2d31e6c91 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -58,6 +58,8 @@ bool btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
 				    struct btrfs_block_group **cache_ret);
 void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
 				     struct extent_buffer *eb);
+int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical,
+			      u64 length);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -145,6 +147,11 @@ btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
 				struct extent_buffer *eb)
 {
 }
+static inline int btrfs_zoned_issue_zeroout(struct btrfs_device *device,
+					    u64 physical, u64 length)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 34/41] btrfs: support dev-replace in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (31 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 33/41] btrfs: implement copying " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 35/41] btrfs: enable relocation " Naohiro Aota
                     ` (7 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is 4/4 patch to implement device-replace on ZONED mode.

Even after the copying is done, the write pointers of the source device and
the destination device may not be synchronized. For example, when the last
allocated extent is freed before device-replace process, the extent is not
copied, leaving a hole there.

This patch synchronize the write pointers by writing zeros to the
destination device.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/scrub.c | 36 +++++++++++++++++++++++++
 fs/btrfs/zoned.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h |  8 ++++++
 3 files changed, 113 insertions(+)

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 65e460670160..2e607caa5ab9 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -3019,6 +3019,31 @@ static void sync_replace_for_zoned(struct scrub_ctx *sctx)
 		   atomic_read(&sctx->bios_in_flight) == 0);
 }
 
+static int sync_write_pointer_for_zoned(struct scrub_ctx *sctx, u64 logical,
+					u64 physical, u64 physical_end)
+{
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	int ret = 0;
+
+	if (!btrfs_fs_incompat(fs_info, ZONED))
+		return 0;
+
+	wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
+
+	mutex_lock(&sctx->wr_lock);
+	if (sctx->write_pointer < physical_end) {
+		ret = btrfs_sync_zone_write_pointer(sctx->wr_tgtdev, logical,
+						    physical,
+						    sctx->write_pointer);
+		if (ret)
+			btrfs_err(fs_info, "failed to recover write pointer");
+	}
+	mutex_unlock(&sctx->wr_lock);
+	btrfs_dev_clear_zone_empty(sctx->wr_tgtdev, physical);
+
+	return ret;
+}
+
 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 					   struct map_lookup *map,
 					   struct btrfs_device *scrub_dev,
@@ -3416,6 +3441,17 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 	blk_finish_plug(&plug);
 	btrfs_free_path(path);
 	btrfs_free_path(ppath);
+
+	if (sctx->is_dev_replace && ret >= 0) {
+		int ret2;
+
+		ret2 = sync_write_pointer_for_zoned(sctx, base + offset,
+						    map->stripes[num].physical,
+						    physical_end);
+		if (ret2)
+			ret = ret2;
+	}
+
 	return ret < 0 ? ret : 0;
 }
 
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 7ff2a590c93f..f28a70eaa20a 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -18,6 +18,7 @@
 #include "block-group.h"
 #include "transaction.h"
 #include "dev-replace.h"
+#include "space-info.h"
 
 /* Maximum number of zones to report per blkdev_report_zones() call */
 #define BTRFS_REPORT_NR_ZONES   4096
@@ -1195,3 +1196,71 @@ int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical,
 				    length >> SECTOR_SHIFT,
 				    GFP_NOFS, 0);
 }
+
+static int read_zone_info(struct btrfs_fs_info *fs_info, u64 logical,
+			  struct blk_zone *zone)
+{
+	struct btrfs_bio *bbio = NULL;
+	u64 mapped_length = PAGE_SIZE;
+	unsigned int nofs_flag;
+	int nmirrors;
+	int i, ret;
+
+	ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
+			       &mapped_length, &bbio);
+	if (ret || !bbio || mapped_length < PAGE_SIZE) {
+		btrfs_put_bbio(bbio);
+		return -EIO;
+	}
+
+	if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK)
+		return -EINVAL;
+
+	nofs_flag = memalloc_nofs_save();
+	nmirrors = (int)bbio->num_stripes;
+	for (i = 0; i < nmirrors; i++) {
+		u64 physical = bbio->stripes[i].physical;
+		struct btrfs_device *dev = bbio->stripes[i].dev;
+
+		/* missing device */
+		if (!dev->bdev)
+			continue;
+
+		ret = btrfs_get_dev_zone(dev, physical, zone);
+		/* failing device */
+		if (ret == -EIO || ret == -EOPNOTSUPP)
+			continue;
+		break;
+	}
+	memalloc_nofs_restore(nofs_flag);
+
+	return ret;
+}
+
+int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev, u64 logical,
+				    u64 physical_start, u64 physical_pos)
+{
+	struct btrfs_fs_info *fs_info = tgt_dev->fs_info;
+	struct blk_zone zone;
+	u64 length;
+	u64 wp;
+	int ret;
+
+	if (!btrfs_dev_is_sequential(tgt_dev, physical_pos))
+		return 0;
+
+	ret = read_zone_info(fs_info, logical, &zone);
+	if (ret)
+		return ret;
+
+	wp = physical_start + ((zone.wp - zone.start) << SECTOR_SHIFT);
+
+	if (physical_pos == wp)
+		return 0;
+
+	if (physical_pos > wp)
+		return -EUCLEAN;
+
+	length = wp - physical_pos;
+	return btrfs_zoned_issue_zeroout(tgt_dev, physical_pos, length);
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index d5b2d31e6c91..d857538660f1 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -60,6 +60,8 @@ void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
 				     struct extent_buffer *eb);
 int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical,
 			      u64 length);
+int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev, u64 logical,
+				  u64 physical_start, u64 physical_pos);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -152,6 +154,12 @@ static inline int btrfs_zoned_issue_zeroout(struct btrfs_device *device,
 {
 	return -EOPNOTSUPP;
 }
+static inline int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev,
+						u64 logical, u64 physical_start,
+						u64 physical_pos)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 35/41] btrfs: enable relocation in ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (32 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 34/41] btrfs: support dev-replace in ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 36/41] btrfs: relocate block group to repair IO failure in ZONED Naohiro Aota
                     ` (6 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

To serialize allocation and submit_bio, we introduced mutex around them. As
a result, preallocation must be completely disabled to avoid a deadlock.

Since current relocation process relies on preallocation to move file data
extents, it must be handled in another way. In ZONED mode, we just truncate
the inode to the size that we wanted to pre-allocate. Then, we flush dirty
pages on the file before finishing relocation process.
run_delalloc_zoned() will handle all the allocation and submit IOs to the
underlying layers.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/relocation.c | 35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 3602806d71bd..3fa60065b483 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2603,6 +2603,32 @@ static noinline_for_stack int prealloc_file_extent_cluster(
 	if (ret)
 		return ret;
 
+	/*
+	 * In ZONED mode, we cannot preallocate the file region. Instead, we
+	 * dirty and fiemap_write the region.
+	 */
+
+	if (btrfs_fs_incompat(inode->root->fs_info, ZONED)) {
+		struct btrfs_root *root = inode->root;
+		struct btrfs_trans_handle *trans;
+
+		end = cluster->end - offset + 1;
+		trans = btrfs_start_transaction(root, 1);
+		if (IS_ERR(trans))
+			return PTR_ERR(trans);
+
+		inode->vfs_inode.i_ctime = current_time(&inode->vfs_inode);
+		i_size_write(&inode->vfs_inode, end);
+		ret = btrfs_update_inode(trans, root, &inode->vfs_inode);
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			btrfs_end_transaction(trans);
+			return ret;
+		}
+
+		return btrfs_end_transaction(trans);
+	}
+
 	inode_lock(&inode->vfs_inode);
 	for (nr = 0; nr < cluster->nr; nr++) {
 		start = cluster->boundary[nr] - offset;
@@ -2799,6 +2825,8 @@ static int relocate_file_extent_cluster(struct inode *inode,
 		}
 	}
 	WARN_ON(nr != cluster->nr);
+	if (btrfs_fs_incompat(fs_info, ZONED) && !ret)
+		ret = btrfs_wait_ordered_range(inode, 0, (u64)-1);
 out:
 	kfree(ra);
 	return ret;
@@ -3434,8 +3462,12 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
 	struct btrfs_path *path;
 	struct btrfs_inode_item *item;
 	struct extent_buffer *leaf;
+	u64 flags = BTRFS_INODE_NOCOMPRESS | BTRFS_INODE_PREALLOC;
 	int ret;
 
+	if (btrfs_fs_incompat(trans->fs_info, ZONED))
+		flags &= ~BTRFS_INODE_PREALLOC;
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -3450,8 +3482,7 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
 	btrfs_set_inode_generation(leaf, item, 1);
 	btrfs_set_inode_size(leaf, item, 0);
 	btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
-	btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS |
-					  BTRFS_INODE_PREALLOC);
+	btrfs_set_inode_flags(leaf, item, flags);
 	btrfs_mark_buffer_dirty(leaf);
 out:
 	btrfs_free_path(path);
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 36/41] btrfs: relocate block group to repair IO failure in ZONED
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (33 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 35/41] btrfs: enable relocation " Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 37/41] btrfs: split alloc_log_tree() Naohiro Aota
                     ` (5 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik

When btrfs find a checksum error and if the file system has a mirror of the
damaged data, btrfs read the correct data from the mirror and write the
data to damaged blocks. This repairing, however, is against the sequential
write required rule.

We can consider three methods to repair an IO failure in ZONED mode:
(1) Reset and rewrite the damaged zone
(2) Allocate new device extent and replace the damaged device extent to the
    new extent
(3) Relocate the corresponding block group

Method (1) is most similar to a behavior done with regular devices.
However, it also wipes non-damaged data in the same device extent, and so
it unnecessary degrades non-damaged data.

Method (2) is much like device replacing but done in the same device. It is
safe because it keeps the device extent until the replacing finish.
However, extending device replacing is non-trivial. It assumes
"src_dev->physical == dst_dev->physical". Also, the extent mapping
replacing function should be extended to support replacing device extent
position in one device.

Method (3) invokes relocation of the damaged block group, so it is
straightforward to implement. It relocates all the mirrored device extents,
so it is, potentially, a more costly operation than method (1) or (2). But
it relocates only using extents which reduce the total IO size.

Let's apply method (3) for now. In the future, we can extend device-replace
and apply method (2).

For protecting a block group gets relocated multiple time with multiple IO
errors, this commit introduces "relocating_repair" bit to show it's now
relocating to repair IO failures. Also it uses a new kthread
"btrfs-relocating-repair", not to block IO path with relocating process.

This commit also supports repairing in the scrub process.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.h |  1 +
 fs/btrfs/extent_io.c   |  3 ++
 fs/btrfs/scrub.c       |  3 ++
 fs/btrfs/volumes.c     | 71 ++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/volumes.h     |  1 +
 5 files changed, 79 insertions(+)

diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index e91123495d68..50e5ddb0a19b 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -96,6 +96,7 @@ struct btrfs_block_group {
 	unsigned int has_caching_ctl:1;
 	unsigned int removed:1;
 	unsigned int to_copy:1;
+	unsigned int relocating_repair:1;
 
 	int disk_cache_state;
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index ed6a9fce016d..b93c67e8ba1d 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2268,6 +2268,9 @@ int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
 	ASSERT(!(fs_info->sb->s_flags & SB_RDONLY));
 	BUG_ON(!mirror_num);
 
+	if (btrfs_fs_incompat(fs_info, ZONED))
+		return btrfs_repair_one_zone(fs_info, logical);
+
 	bio = btrfs_io_bio_alloc(1);
 	bio->bi_iter.bi_size = 0;
 	map_length = length;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 2e607caa5ab9..4c247a1618d0 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -861,6 +861,9 @@ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
 	have_csum = sblock_to_check->pagev[0]->have_csum;
 	dev = sblock_to_check->pagev[0]->dev;
 
+	if (btrfs_fs_incompat(fs_info, ZONED) && !sctx->is_dev_replace)
+		return btrfs_repair_one_zone(fs_info, logical);
+
 	/*
 	 * We must use GFP_NOFS because the scrub task might be waiting for a
 	 * worker task executing this function and in turn a transaction commit
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index af2ed4d3389f..33380f20a206 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -7975,3 +7975,74 @@ bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr)
 	spin_unlock(&fs_info->swapfile_pins_lock);
 	return node != NULL;
 }
+
+static int relocating_repair_kthread(void *data)
+{
+	struct btrfs_block_group *cache = (struct btrfs_block_group *) data;
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	u64 target;
+	int ret = 0;
+
+	target = cache->start;
+	btrfs_put_block_group(cache);
+
+	if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
+		btrfs_info(fs_info,
+			   "skip relocating block group %llu to repair: EBUSY",
+			   target);
+		return -EBUSY;
+	}
+
+	mutex_lock(&fs_info->delete_unused_bgs_mutex);
+
+	/* ensure Block Group still exists */
+	cache = btrfs_lookup_block_group(fs_info, target);
+	if (!cache)
+		goto out;
+
+	if (!cache->relocating_repair)
+		goto out;
+
+	ret = btrfs_may_alloc_data_chunk(fs_info, target);
+	if (ret < 0)
+		goto out;
+
+	btrfs_info(fs_info, "relocating block group %llu to repair IO failure",
+		   target);
+	ret = btrfs_relocate_chunk(fs_info, target);
+
+out:
+	if (cache)
+		btrfs_put_block_group(cache);
+	mutex_unlock(&fs_info->delete_unused_bgs_mutex);
+	btrfs_exclop_finish(fs_info);
+
+	return ret;
+}
+
+int btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical)
+{
+	struct btrfs_block_group *cache;
+
+	/* do not attempt to repair in degraded state */
+	if (btrfs_test_opt(fs_info, DEGRADED))
+		return 0;
+
+	cache = btrfs_lookup_block_group(fs_info, logical);
+	if (!cache)
+		return 0;
+
+	spin_lock(&cache->lock);
+	if (cache->relocating_repair) {
+		spin_unlock(&cache->lock);
+		btrfs_put_block_group(cache);
+		return 0;
+	}
+	cache->relocating_repair = 1;
+	spin_unlock(&cache->lock);
+
+	kthread_run(relocating_repair_kthread, cache,
+		    "btrfs-relocating-repair");
+
+	return 0;
+}
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index f8fc3debd5e0..7f1a38c820e3 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -584,5 +584,6 @@ void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
 int btrfs_bg_type_to_factor(u64 flags);
 const char *btrfs_bg_type_to_raid_name(u64 flags);
 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info);
+int btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical);
 
 #endif
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 37/41] btrfs: split alloc_log_tree()
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (34 preceding siblings ...)
  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   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group Naohiro Aota
                     ` (4 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is a preparation for the next patch. This commit split
alloc_log_tree() to allocating tree structure part (remains in
alloc_log_tree()) and allocating tree node part (moved in
btrfs_alloc_log_tree_node()). The latter part is also exported to be used
in the next patch.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/disk-io.c | 27 ++++++++++++++++++++++++---
 fs/btrfs/disk-io.h |  2 ++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5ce5b18f9dc4..02b1f9b20bed 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1211,7 +1211,6 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 					 struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *root;
-	struct extent_buffer *leaf;
 
 	root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
 	if (!root)
@@ -1221,6 +1220,14 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
 	root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
 
+	return root;
+}
+
+int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
+			      struct btrfs_root *root)
+{
+	struct extent_buffer *leaf;
+
 	/*
 	 * DON'T set SHAREABLE bit for log trees.
 	 *
@@ -1235,24 +1242,31 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
 			NULL, 0, 0, 0, BTRFS_NESTING_NORMAL);
 	if (IS_ERR(leaf)) {
 		btrfs_put_root(root);
-		return ERR_CAST(leaf);
+		return PTR_ERR(leaf);
 	}
 
 	root->node = leaf;
 
 	btrfs_mark_buffer_dirty(root->node);
 	btrfs_tree_unlock(root->node);
-	return root;
+
+	return 0;
 }
 
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *log_root;
+	int ret;
 
 	log_root = alloc_log_tree(trans, fs_info);
 	if (IS_ERR(log_root))
 		return PTR_ERR(log_root);
+	ret = btrfs_alloc_log_tree_node(trans, log_root);
+	if (ret) {
+		kfree(log_root);
+		return ret;
+	}
 	WARN_ON(fs_info->log_root_tree);
 	fs_info->log_root_tree = log_root;
 	return 0;
@@ -1264,11 +1278,18 @@ int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_root *log_root;
 	struct btrfs_inode_item *inode_item;
+	int ret;
 
 	log_root = alloc_log_tree(trans, fs_info);
 	if (IS_ERR(log_root))
 		return PTR_ERR(log_root);
 
+	ret = btrfs_alloc_log_tree_node(trans, log_root);
+	if (ret) {
+		kfree(log_root);
+		return ret;
+	}
+
 	log_root->last_trans = trans->transid;
 	log_root->root_key.offset = root->root_key.objectid;
 
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index fee69ced58b4..b82ae3711c42 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -115,6 +115,8 @@ blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 			extent_submit_bio_start_t *submit_bio_start);
 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
 			  int mirror_num);
+int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
+			      struct btrfs_root *root);
 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info);
 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (35 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 37/41] btrfs: split alloc_log_tree() Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-13 16:26     ` David Sterba
  2020-10-01 18:36   ` [PATCH v8 39/41] btrfs: serialize log transaction on ZONED mode Naohiro Aota
                     ` (3 subsequent siblings)
  40 siblings, 1 reply; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is the 1/3 patch to enable tree log on ZONED mode.

The tree-log feature does not work on ZONED mode as is. Blocks for a
tree-log tree are allocated mixed with other metadata blocks, and btrfs
writes and syncs the tree-log blocks to devices at the time of fsync(),
which is different timing from a global transaction commit. As a result,
both writing tree-log blocks and writing other metadata blocks become
non-sequential writes that ZONED mode must avoid.

We can introduce a dedicated block group for tree-log blocks so that
tree-log blocks and other metadata blocks can be separated write streams.
As a result, each write stream can now be written to devices separately.
"fs_info->treelog_bg" tracks the dedicated block group and btrfs assign
"treelog_bg" on-demand on tree-log block allocation time.

This commit extends the zoned block allocator to use the block group.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/block-group.c |  7 +++++
 fs/btrfs/ctree.h       |  2 ++
 fs/btrfs/extent-tree.c | 65 ++++++++++++++++++++++++++++++++++++++----
 3 files changed, 69 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index d39fa80d3d90..64253d4a7bfc 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -939,6 +939,13 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	btrfs_return_cluster_to_free_space(block_group, cluster);
 	spin_unlock(&cluster->refill_lock);
 
+	if (btrfs_fs_incompat(fs_info, ZONED)) {
+		spin_lock(&fs_info->treelog_bg_lock);
+		if (fs_info->treelog_bg == block_group->start)
+			fs_info->treelog_bg = 0;
+		spin_unlock(&fs_info->treelog_bg_lock);
+	}
+
 	path = btrfs_alloc_path();
 	if (!path) {
 		ret = -ENOMEM;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index d021bc4a92cd..81e2f5b78917 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -954,6 +954,8 @@ struct btrfs_fs_info {
 	unsigned long exclusive_operation;
 
 	struct mutex zoned_meta_io_lock;
+	spinlock_t treelog_bg_lock;
+	u64 treelog_bg;
 
 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
 	spinlock_t ref_verify_lock;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index f44faaf7aca2..c4d382e5b45f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3656,6 +3656,9 @@ struct find_free_extent_ctl {
 
 	/* Allocation policy */
 	enum btrfs_extent_allocation_policy policy;
+
+	/* Allocation is called for tree-log */
+	bool for_treelog;
 };
 
 
@@ -3856,23 +3859,54 @@ static int do_allocation_zoned(struct btrfs_block_group *block_group,
 			       struct find_free_extent_ctl *ffe_ctl,
 			       struct btrfs_block_group **bg_ret)
 {
+	struct btrfs_fs_info *fs_info = block_group->fs_info;
 	struct btrfs_space_info *space_info = block_group->space_info;
 	struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
 	u64 start = block_group->start;
 	u64 num_bytes = ffe_ctl->num_bytes;
 	u64 avail;
+	u64 bytenr = block_group->start;
+	u64 log_bytenr;
 	int ret = 0;
+	bool skip;
 
 	ASSERT(btrfs_fs_incompat(block_group->fs_info, ZONED));
 
+	/*
+	 * Do not allow non-tree-log blocks in the dedicated tree-log block
+	 * group, and vice versa.
+	 */
+	spin_lock(&fs_info->treelog_bg_lock);
+	log_bytenr = fs_info->treelog_bg;
+	skip = log_bytenr && ((ffe_ctl->for_treelog && bytenr != log_bytenr) ||
+			      (!ffe_ctl->for_treelog && bytenr == log_bytenr));
+	spin_unlock(&fs_info->treelog_bg_lock);
+	if (skip)
+		return 1;
+
 	spin_lock(&space_info->lock);
 	spin_lock(&block_group->lock);
+	spin_lock(&fs_info->treelog_bg_lock);
+
+	ASSERT(!ffe_ctl->for_treelog ||
+	       block_group->start == fs_info->treelog_bg ||
+	       fs_info->treelog_bg == 0);
 
 	if (block_group->ro) {
 		ret = 1;
 		goto out;
 	}
 
+	/*
+	 * Do not allow currently using block group to be tree-log dedicated
+	 * block group.
+	 */
+	if (ffe_ctl->for_treelog && !fs_info->treelog_bg &&
+	    (block_group->used || block_group->reserved)) {
+		ret = 1;
+		goto out;
+	}
+
 	avail = block_group->length - block_group->alloc_offset;
 	if (avail < num_bytes) {
 		ffe_ctl->max_extent_size = avail;
@@ -3880,6 +3914,9 @@ static int do_allocation_zoned(struct btrfs_block_group *block_group,
 		goto out;
 	}
 
+	if (ffe_ctl->for_treelog && !fs_info->treelog_bg)
+		fs_info->treelog_bg = block_group->start;
+
 	ffe_ctl->found_offset = start + block_group->alloc_offset;
 	block_group->alloc_offset += num_bytes;
 	spin_lock(&ctl->tree_lock);
@@ -3887,10 +3924,13 @@ static int do_allocation_zoned(struct btrfs_block_group *block_group,
 	spin_unlock(&ctl->tree_lock);
 
 	ASSERT(IS_ALIGNED(ffe_ctl->found_offset,
-			  block_group->fs_info->stripesize));
+			  fs_info->stripesize));
 	ffe_ctl->search_start = ffe_ctl->found_offset;
 
 out:
+	if (ret && ffe_ctl->for_treelog)
+		fs_info->treelog_bg = 0;
+	spin_unlock(&fs_info->treelog_bg_lock);
 	spin_unlock(&block_group->lock);
 	spin_unlock(&space_info->lock);
 	return ret;
@@ -4140,7 +4180,12 @@ static int prepare_allocation(struct btrfs_fs_info *fs_info,
 		return prepare_allocation_clustered(fs_info, ffe_ctl,
 						    space_info, ins);
 	case BTRFS_EXTENT_ALLOC_ZONED:
-		/* nothing to do */
+		if (ffe_ctl->for_treelog) {
+			spin_lock(&fs_info->treelog_bg_lock);
+			if (fs_info->treelog_bg)
+				ffe_ctl->hint_byte = fs_info->treelog_bg;
+			spin_unlock(&fs_info->treelog_bg_lock);
+		}
 		return 0;
 	default:
 		BUG();
@@ -4184,6 +4229,7 @@ static noinline int find_free_extent(struct btrfs_root *root,
 	struct find_free_extent_ctl ffe_ctl = {0};
 	struct btrfs_space_info *space_info;
 	bool full_search = false;
+	bool for_treelog = root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID;
 
 	WARN_ON(num_bytes < fs_info->sectorsize);
 
@@ -4197,6 +4243,7 @@ static noinline int find_free_extent(struct btrfs_root *root,
 	ffe_ctl.orig_have_caching_bg = false;
 	ffe_ctl.found_offset = 0;
 	ffe_ctl.hint_byte = hint_byte_orig;
+	ffe_ctl.for_treelog = for_treelog;
 	ffe_ctl.policy = BTRFS_EXTENT_ALLOC_CLUSTERED;
 
 	/* For clustered allocation */
@@ -4271,8 +4318,15 @@ static noinline int find_free_extent(struct btrfs_root *root,
 		struct btrfs_block_group *bg_ret;
 
 		/* If the block group is read-only, we can skip it entirely. */
-		if (unlikely(block_group->ro))
+		if (unlikely(block_group->ro)) {
+			if (btrfs_fs_incompat(fs_info, ZONED) && for_treelog) {
+				spin_lock(&fs_info->treelog_bg_lock);
+				if (block_group->start == fs_info->treelog_bg)
+					fs_info->treelog_bg = 0;
+				spin_unlock(&fs_info->treelog_bg_lock);
+			}
 			continue;
+		}
 
 		btrfs_grab_block_group(block_group, delalloc);
 		ffe_ctl.search_start = block_group->start;
@@ -4460,6 +4514,7 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 	bool final_tried = num_bytes == min_alloc_size;
 	u64 flags;
 	int ret;
+	bool for_treelog = root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID;
 
 	flags = get_alloc_profile_by_root(root, is_data);
 again:
@@ -4483,8 +4538,8 @@ int btrfs_reserve_extent(struct btrfs_root *root, u64 ram_bytes,
 
 			sinfo = btrfs_find_space_info(fs_info, flags);
 			btrfs_err(fs_info,
-				  "allocation failed flags %llu, wanted %llu",
-				  flags, num_bytes);
+			"allocation failed flags %llu, wanted %llu treelog %d",
+				  flags, num_bytes, for_treelog);
 			if (sinfo)
 				btrfs_dump_space_info(fs_info, sinfo,
 						      num_bytes, 1);
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 39/41] btrfs: serialize log transaction on ZONED mode
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (36 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-01 18:36   ` [PATCH v8 40/41] btrfs: reorder log node allocation Naohiro Aota
                     ` (2 subsequent siblings)
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is the 2/3 patch to enable tree-log on ZONED mode.

Since we can start more than one log transactions per subvolume
simultaneously, nodes from multiple transactions can be allocated
interleaved. Such mixed allocation results in non-sequential writes at the
time of log transaction commit. The nodes of the global log root tree
(fs_info->log_root_tree), also have the same mixed allocation problem.

This patch serializes log transactions by waiting for a committing
transaction when someone tries to start a new transaction, to avoid the
mixed allocation problem. We must also wait for running log transactions
from another subvolume, but there is no easy way to detect which subvolume
root is running a log transaction. So, this patch forbids starting a new
log transaction when other subvolumes already allocated the global log root
tree.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/tree-log.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 5f585cf57383..42175b8d1bee 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -106,6 +106,7 @@ static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans,
 				       struct btrfs_root *log,
 				       struct btrfs_path *path,
 				       u64 dirid, int del_all);
+static void wait_log_commit(struct btrfs_root *root, int transid);
 
 /*
  * tree logging is a special write ahead log used to make sure that
@@ -140,16 +141,25 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 			   struct btrfs_log_ctx *ctx)
 {
 	struct btrfs_fs_info *fs_info = root->fs_info;
+	bool zoned = btrfs_fs_incompat(fs_info, ZONED);
 	int ret = 0;
 
 	mutex_lock(&root->log_mutex);
 
+again:
 	if (root->log_root) {
+		int index = (root->log_transid + 1) % 2;
+
 		if (btrfs_need_log_full_commit(trans)) {
 			ret = -EAGAIN;
 			goto out;
 		}
 
+		if (zoned && atomic_read(&root->log_commit[index])) {
+			wait_log_commit(root, root->log_transid - 1);
+			goto again;
+		}
+
 		if (!root->log_start_pid) {
 			clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state);
 			root->log_start_pid = current->pid;
@@ -158,8 +168,13 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 		}
 	} else {
 		mutex_lock(&fs_info->tree_log_mutex);
-		if (!fs_info->log_root_tree)
+		if (zoned && fs_info->log_root_tree) {
+			ret = -EAGAIN;
+			mutex_unlock(&fs_info->tree_log_mutex);
+			goto out;
+		} else if (!fs_info->log_root_tree) {
 			ret = btrfs_init_log_root_tree(trans, fs_info);
+		}
 		mutex_unlock(&fs_info->tree_log_mutex);
 		if (ret)
 			goto out;
@@ -193,14 +208,22 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
  */
 static int join_running_log_trans(struct btrfs_root *root)
 {
+	bool zoned = btrfs_fs_incompat(root->fs_info, ZONED);
 	int ret = -ENOENT;
 
 	if (!test_bit(BTRFS_ROOT_HAS_LOG_TREE, &root->state))
 		return ret;
 
 	mutex_lock(&root->log_mutex);
+again:
 	if (root->log_root) {
+		int index = (root->log_transid + 1) % 2;
+
 		ret = 0;
+		if (zoned && atomic_read(&root->log_commit[index])) {
+			wait_log_commit(root, root->log_transid - 1);
+			goto again;
+		}
 		atomic_inc(&root->log_writers);
 	}
 	mutex_unlock(&root->log_mutex);
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 40/41] btrfs: reorder log node allocation
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (37 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 39/41] btrfs: serialize log transaction on ZONED mode Naohiro Aota
@ 2020-10-01 18:36   ` 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
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota

This is the 3/3 patch to enable tree-log on ZONED mode.

The allocation order of nodes of "fs_info->log_root_tree" and nodes of
"root->log_root" is not the same as the writing order of them. So, the
writing causes unaligned write errors.

This patch reorders the allocation of them by delaying allocation of the
root node of "fs_info->log_root_tree," so that the node buffers can go out
sequentially to devices.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/disk-io.c  |  6 ------
 fs/btrfs/tree-log.c | 19 +++++++++++++------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 02b1f9b20bed..0c041ad096ac 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1257,16 +1257,10 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 			     struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *log_root;
-	int ret;
 
 	log_root = alloc_log_tree(trans, fs_info);
 	if (IS_ERR(log_root))
 		return PTR_ERR(log_root);
-	ret = btrfs_alloc_log_tree_node(trans, log_root);
-	if (ret) {
-		kfree(log_root);
-		return ret;
-	}
 	WARN_ON(fs_info->log_root_tree);
 	fs_info->log_root_tree = log_root;
 	return 0;
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 42175b8d1bee..7a4bfedb2929 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3143,6 +3143,11 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]);
 	root_log_ctx.log_transid = log_root_tree->log_transid;
 
+	mutex_lock(&fs_info->tree_log_mutex);
+	if (!log_root_tree->node)
+		btrfs_alloc_log_tree_node(trans, log_root_tree);
+	mutex_unlock(&fs_info->tree_log_mutex);
+
 	/*
 	 * Now we are safe to update the log_root_tree because we're under the
 	 * log_mutex, and we're a current writer so we're holding the commit
@@ -3292,12 +3297,14 @@ static void free_log_tree(struct btrfs_trans_handle *trans,
 		.process_func = process_one_buffer
 	};
 
-	ret = walk_log_tree(trans, log, &wc);
-	if (ret) {
-		if (trans)
-			btrfs_abort_transaction(trans, ret);
-		else
-			btrfs_handle_fs_error(log->fs_info, ret, NULL);
+	if (log->node) {
+		ret = walk_log_tree(trans, log, &wc);
+		if (ret) {
+			if (trans)
+				btrfs_abort_transaction(trans, ret);
+			else
+				btrfs_handle_fs_error(log->fs_info, ret, NULL);
+		}
 	}
 
 	clear_extent_bits(&log->dirty_log_pages, 0, (u64)-1,
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* [PATCH v8 41/41] btrfs: enable to mount ZONED incompat flag
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (38 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 40/41] btrfs: reorder log node allocation Naohiro Aota
@ 2020-10-01 18:36   ` Naohiro Aota
  2020-10-02 13:39   ` [PATCH v8 01/41] block: add bio_add_zone_append_page Martin K. Petersen
  40 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-01 18:36 UTC (permalink / raw)
  To: linux-btrfs, dsterba; +Cc: hare, linux-fsdevel, Naohiro Aota, Josef Bacik

This final patch adds the ZONED incompat flag to
BTRFS_FEATURE_INCOMPAT_SUPP and enables btrfs to mount ZONED flagged file
system.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/ctree.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 81e2f5b78917..f5b78ae3baff 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -302,7 +302,8 @@ struct btrfs_super_block {
 	 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA |	\
 	 BTRFS_FEATURE_INCOMPAT_NO_HOLES	|	\
 	 BTRFS_FEATURE_INCOMPAT_METADATA_UUID	|	\
-	 BTRFS_FEATURE_INCOMPAT_RAID1C34)
+	 BTRFS_FEATURE_INCOMPAT_RAID1C34	|	\
+	 BTRFS_FEATURE_INCOMPAT_ZONED)
 
 #define BTRFS_FEATURE_INCOMPAT_SAFE_SET			\
 	(BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
-- 
2.27.0


^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 01/41] block: add bio_add_zone_append_page
  2020-10-01 18:36 ` [PATCH v8 01/41] block: add bio_add_zone_append_page Naohiro Aota
                     ` (39 preceding siblings ...)
  2020-10-01 18:36   ` [PATCH v8 41/41] btrfs: enable to mount ZONED incompat flag Naohiro Aota
@ 2020-10-02 13:39   ` Martin K. Petersen
  2020-10-05  1:46     ` Damien Le Moal
  2020-10-05 13:43     ` Christoph Hellwig
  40 siblings, 2 replies; 60+ messages in thread
From: Martin K. Petersen @ 2020-10-02 13:39 UTC (permalink / raw)
  To: Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Johannes Thumshirn


Naohiro/Johannes,

> Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which
> is intended to be used by file systems that directly add pages to a bio
> instead of using bio_iov_iter_get_pages().

Why use the hardware limit? For filesystem I/O we generally use the
queue soft limit to prevent I/Os getting too big which can lead to very
unpredictable latency in mixed workloads.

max_zone_append_sectors also appears to be gated exclusively by hardware
constraints. Is there user-controllable limit in place for append
operations?

-- 
Martin K. Petersen	Oracle Linux Engineering

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 01/41] block: add bio_add_zone_append_page
  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
  1 sibling, 0 replies; 60+ messages in thread
From: Damien Le Moal @ 2020-10-05  1:46 UTC (permalink / raw)
  To: Martin K. Petersen, Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Johannes Thumshirn

On 2020/10/02 22:39, Martin K. Petersen wrote:
> 
> Naohiro/Johannes,
> 
>> Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which
>> is intended to be used by file systems that directly add pages to a bio
>> instead of using bio_iov_iter_get_pages().
> 
> Why use the hardware limit? For filesystem I/O we generally use the
> queue soft limit to prevent I/Os getting too big which can lead to very
> unpredictable latency in mixed workloads.

max_zone_append_sectors is already gated by max_hw_sectors, but it is not gated
by max_sectors/BLK_DEF_MAX_SECTORS. If we add such gating to
blk_queue_max_zone_append_sectors(), max_zone_append_sectors would become a soft
limit too. So should we have max_zone_append_sectors and
max_hw_zone_append_sectors ?

Which also means that we should tweak queue_max_sectors_store() to gate
max_zone_append_sectors to that limit upon a user change.

> 
> max_zone_append_sectors also appears to be gated exclusively by hardware
> constraints. Is there user-controllable limit in place for append
> operations?

No, none that I know of. At the HW level, max_zone_append_sectors is basically
max_hw_sectors. That is gated by the zone size in
blk_queue_max_zone_append_sectors(). If as mentioned above we tweak
queue_max_sectors_store() to change max_zone_append_sectors too if needed, we
would then have an indirect user-controllable limit. Or we could implement a
queue_zone_append_max_store() too I guess. Yet, having everything indirectly
controlled through queue_max_sectors_store() is probably simpler I think.

-- 
Damien Le Moal
Western Digital Research

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 01/41] block: add bio_add_zone_append_page
  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
  1 sibling, 1 reply; 60+ messages in thread
From: Christoph Hellwig @ 2020-10-05 13:43 UTC (permalink / raw)
  To: Martin K. Petersen
  Cc: Naohiro Aota, linux-btrfs, dsterba, hare, linux-fsdevel,
	Johannes Thumshirn

On Fri, Oct 02, 2020 at 09:39:04AM -0400, Martin K. Petersen wrote:
> 
> Naohiro/Johannes,
> 
> > Add bio_add_zone_append_page(), a wrapper around bio_add_hw_page() which
> > is intended to be used by file systems that directly add pages to a bio
> > instead of using bio_iov_iter_get_pages().
> 
> Why use the hardware limit? For filesystem I/O we generally use the
> queue soft limit to prevent I/Os getting too big which can lead to very
> unpredictable latency in mixed workloads.
> 
> max_zone_append_sectors also appears to be gated exclusively by hardware
> constraints. Is there user-controllable limit in place for append
> operations?

Zone Append operations can't be split, as they return the first written
LBA to the caller.  If you'd split it you'd now need to return multiple
start LBA values.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 01/41] block: add bio_add_zone_append_page
  2020-10-05 13:43     ` Christoph Hellwig
@ 2020-10-06  1:26       ` Martin K. Petersen
  2020-10-06  5:12         ` Damien Le Moal
  0 siblings, 1 reply; 60+ messages in thread
From: Martin K. Petersen @ 2020-10-06  1:26 UTC (permalink / raw)
  To: Christoph Hellwig
  Cc: Martin K. Petersen, Naohiro Aota, linux-btrfs, dsterba, hare,
	linux-fsdevel, Johannes Thumshirn


Christoph,

>> max_zone_append_sectors also appears to be gated exclusively by hardware
>> constraints. Is there user-controllable limit in place for append
>> operations?
>
> Zone Append operations can't be split, as they return the first written
> LBA to the caller.  If you'd split it you'd now need to return multiple
> start LBA values.

Yep, this limit would have to be enforced at the top.

Anyway, not sure how important this is given modern drives. I just know
that for our workloads the soft limit is something we almost always end
up tweaking.

-- 
Martin K. Petersen	Oracle Linux Engineering

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 01/41] block: add bio_add_zone_append_page
  2020-10-06  1:26       ` Martin K. Petersen
@ 2020-10-06  5:12         ` Damien Le Moal
  0 siblings, 0 replies; 60+ messages in thread
From: Damien Le Moal @ 2020-10-06  5:12 UTC (permalink / raw)
  To: Martin K. Petersen, hch
  Cc: Naohiro Aota, linux-btrfs, dsterba, hare, linux-fsdevel,
	Johannes Thumshirn

On 2020/10/06 10:27, Martin K. Petersen wrote:
> 
> Christoph,
> 
>>> max_zone_append_sectors also appears to be gated exclusively by hardware
>>> constraints. Is there user-controllable limit in place for append
>>> operations?
>>
>> Zone Append operations can't be split, as they return the first written
>> LBA to the caller.  If you'd split it you'd now need to return multiple
>> start LBA values.
> 
> Yep, this limit would have to be enforced at the top.
> 
> Anyway, not sure how important this is given modern drives. I just know
> that for our workloads the soft limit is something we almost always end
> up tweaking.

We can fix the max_zone_append_sectors limit independently of this btrfs series.
Right now, this attribute represents the hardware limit but we can easily rename
it to max_hw_zone_append_sectors and define a soft max_zone_append_sectors which
would be min(max_sectors, max_hw_zone_append_sectors). That will result in
similar soft limit control as for regular writes & max_sectors/max_hw_sectors.

-- 
Damien Le Moal
Western Digital Research

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 00/41] btrfs: zoned block device support
  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
@ 2020-10-09 15:40 ` Josef Bacik
  2020-10-12  9:17   ` Naohiro Aota
  1 sibling, 1 reply; 60+ messages in thread
From: Josef Bacik @ 2020-10-09 15:40 UTC (permalink / raw)
  To: Naohiro Aota, linux-btrfs, dsterba; +Cc: hare, linux-fsdevel

On 10/1/20 2:36 PM, Naohiro Aota wrote:
> This series adds zoned block device support to btrfs.
> 
> Changes from v7:
>   - Use bio_add_hw_page() to build up bio to honor hardware restrictions
>     - add bio_add_zone_append_page() as a wrapper of the function
>   - Split file extent on submitting bio
>     - If bio_add_zone_append_page() fails, split the file extent and send
>       out bio
>     - so, we can ensure one bio == one file extent
>   - Fix build bot issues
>   - Rebased on misc-next
> 

This is too big of a patch series for it to not conflict with some change to 
misc-next after a few days.  I finally sat down to run this through xfstests 
locally and I couldn't get the patches to apply cleanly.  Could you push this to 
a git branch publicly somewhere so I can just pull from that branch to do the 
xfstests testing I want to do while I'm reviewing it?  Thanks,

Josef

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 00/41] btrfs: zoned block device support
  2020-10-09 15:40 ` [PATCH v8 00/41] btrfs: zoned block device support Josef Bacik
@ 2020-10-12  9:17   ` Naohiro Aota
  0 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-12  9:17 UTC (permalink / raw)
  To: Josef Bacik; +Cc: linux-btrfs, dsterba, hare, linux-fsdevel

On Fri, Oct 09, 2020 at 11:40:36AM -0400, Josef Bacik wrote:
>On 10/1/20 2:36 PM, Naohiro Aota wrote:
>>This series adds zoned block device support to btrfs.
>>
>>Changes from v7:
>>  - Use bio_add_hw_page() to build up bio to honor hardware restrictions
>>    - add bio_add_zone_append_page() as a wrapper of the function
>>  - Split file extent on submitting bio
>>    - If bio_add_zone_append_page() fails, split the file extent and send
>>      out bio
>>    - so, we can ensure one bio == one file extent
>>  - Fix build bot issues
>>  - Rebased on misc-next
>>
>
>This is too big of a patch series for it to not conflict with some 
>change to misc-next after a few days.  I finally sat down to run this 
>through xfstests locally and I couldn't get the patches to apply 
>cleanly.  Could you push this to a git branch publicly somewhere so I 
>can just pull from that branch to do the xfstests testing I want to do 
>while I'm reviewing it?  Thanks,
>
>Josef

Indeed. I pushed zoned btrfs kernel & userland tools to the branches below.

I also prepared pre-compiled userland binaries because they require patched
util-linux (libblkid) to deal with the log-structured superblock.

kernel https://github.com/naota/linux/tree/btrfs-zoned
userland https://github.com/naota/btrfs-progs/tree/btrfs-zoned
pre-compiled userland https://wdc.app.box.com/s/fnhqsb3otrvgkstq66o6bvdw6tk525kp

Thanks,
Naohiro

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 07/41] btrfs: disallow NODATACOW in ZONED mode
  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
  0 siblings, 1 reply; 60+ messages in thread
From: David Sterba @ 2020-10-13 15:39 UTC (permalink / raw)
  To: Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Johannes Thumshirn,
	Josef Bacik

On Fri, Oct 02, 2020 at 03:36:14AM +0900, Naohiro Aota wrote:
> NODATACOW implies overwriting the file data on a device, which is
> impossible in sequential required zones. Disable NODATACOW globally with
> mount option and per-file NODATACOW attribute by masking FS_NOCOW_FL.
> 
> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
> Reviewed-by: Josef Bacik <josef@toxicpanda.com>
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
> ---
>  fs/btrfs/ioctl.c | 3 +++
>  fs/btrfs/zoned.c | 6 ++++++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index ab408a23ba32..5d592da4e2ff 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -91,6 +91,9 @@ struct btrfs_ioctl_send_args_32 {
>  static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
>  		unsigned int flags)
>  {
> +	if (btrfs_fs_incompat(btrfs_sb(inode->i_sb), ZONED))
> +		flags &= ~FS_NOCOW_FL;
> +

This can't be inside the function, the 'type' here is for inode that
does not know anything about zoned mode. The right place is after
check_fsflags in btrfs_ioctl_setflags in a helper like:

	ret = check_fsflags_compatible(fs_info, flags));
	if (ret)
		goto out_unlock;

and check_fsflags_compatible checks for zoned mode and NOCOW and returns
-EPERM, not silently unmasking it.

>  	if (S_ISDIR(inode->i_mode))
>  		return flags;
>  	else if (S_ISREG(inode->i_mode))

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 10/41] btrfs: disallow inode_cache in ZONED mode
  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
  0 siblings, 1 reply; 60+ messages in thread
From: David Sterba @ 2020-10-13 15:41 UTC (permalink / raw)
  To: Naohiro Aota; +Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik

On Fri, Oct 02, 2020 at 03:36:17AM +0900, Naohiro Aota wrote:
> inode_cache use pre-allocation to write its cache data. However,
> pre-allocation is completely disabled in ZONED mode.
> 
> We can technically enable inode_cache in the same way as relocation.
> However, inode_cache is rarely used and the man page discourage using it.
> So, let's just disable it for now.

Don't worry about the inode_cache mount option, it's been deprecated
as of commit b547a88ea5776a8092f7 and will be removed in 5.11.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 03/41] btrfs: Get zone information of zoned block devices
  2020-10-01 18:36   ` [PATCH v8 03/41] btrfs: Get zone information of zoned block devices Naohiro Aota
@ 2020-10-13 15:53     ` David Sterba
  2020-10-15  7:45       ` Johannes Thumshirn
  0 siblings, 1 reply; 60+ messages in thread
From: David Sterba @ 2020-10-13 15:53 UTC (permalink / raw)
  To: Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik, Damien Le Moal

On Fri, Oct 02, 2020 at 03:36:10AM +0900, Naohiro Aota wrote:
> --- 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

As this is conditionally built in, it should be also added to the string
printed by btrfs_print_mod_info and we want the actual status so

#ifdef CONFIG_BLK_DEV_ZONED
	", zoned=yes"
#else
	", zoned=no"
#endif

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 04/41] btrfs: Check and enable ZONED mode
  2020-10-01 18:36   ` [PATCH v8 04/41] btrfs: Check and enable ZONED mode Naohiro Aota
@ 2020-10-13 15:56     ` David Sterba
  2020-10-13 16:13     ` David Sterba
  1 sibling, 0 replies; 60+ messages in thread
From: David Sterba @ 2020-10-13 15:56 UTC (permalink / raw)
  To: Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik, Damien Le Moal

On Fri, Oct 02, 2020 at 03:36:11AM +0900, Naohiro Aota wrote:
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -588,6 +588,9 @@ struct btrfs_fs_info {
>  	struct btrfs_root *free_space_root;
>  	struct btrfs_root *data_reloc_root;
>  
> +	/* Zone size when in ZONED mode */
> +	u64 zone_size;

I think this could be reused to avoid the lengthy

	if (btrfs_fs_incompat(fs_info, ZONED))

to do

	if (fs_info->zoned)

In order to keep the semantics of both an anonymouns union should work:

	union {
		u64 zone_size;
		u64 zone;
	};

and the existing usage of zone_size can be kept intact.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 04/41] btrfs: Check and enable ZONED mode
  2020-10-01 18:36   ` [PATCH v8 04/41] btrfs: Check and enable ZONED mode Naohiro Aota
  2020-10-13 15:56     ` David Sterba
@ 2020-10-13 16:13     ` David Sterba
  1 sibling, 0 replies; 60+ messages in thread
From: David Sterba @ 2020-10-13 16:13 UTC (permalink / raw)
  To: Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik, Damien Le Moal

On Fri, Oct 02, 2020 at 03:36:11AM +0900, Naohiro Aota wrote:
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -588,6 +588,9 @@ struct btrfs_fs_info {
>  	struct btrfs_root *free_space_root;
>  	struct btrfs_root *data_reloc_root;
>  
> +	/* Zone size when in ZONED mode */
> +	u64 zone_size;
> +
>  	/* the log root tree is a directory of all the other log roots */
>  	struct btrfs_root *log_root_tree;

This is misplaced, new members should be placed to an existing location
if there is one or at the end of the structure. What's the logic behind
putting zone_size and later max_zone_append_size into the tree root
pointers?

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group
  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
  0 siblings, 1 reply; 60+ messages in thread
From: David Sterba @ 2020-10-13 16:26 UTC (permalink / raw)
  To: Naohiro Aota; +Cc: linux-btrfs, dsterba, hare, linux-fsdevel

On Fri, Oct 02, 2020 at 03:36:45AM +0900, Naohiro Aota wrote:
> --- a/fs/btrfs/extent-tree.c
> +++ b/fs/btrfs/extent-tree.c
> @@ -3656,6 +3656,9 @@ struct find_free_extent_ctl {
>  
>  	/* Allocation policy */
>  	enum btrfs_extent_allocation_policy policy;
> +
> +	/* Allocation is called for tree-log */
> +	bool for_treelog;

There are already bool flags in find_free_extent_ctl, move it after
orig_have_caching_bg.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 25/41] btrfs: use ZONE_APPEND write for ZONED btrfs
  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
  0 siblings, 0 replies; 60+ messages in thread
From: David Sterba @ 2020-10-13 16:45 UTC (permalink / raw)
  To: Naohiro Aota; +Cc: linux-btrfs, dsterba, hare, linux-fsdevel

On Fri, Oct 02, 2020 at 03:36:32AM +0900, Naohiro Aota wrote:
> This commit enables zone append writing for zoned btrfs. Three parts are
> necessary to enable it. First, it modifies bio to use REQ_OP_ZONE_APPEND in
> btrfs_submit_bio_hook() and adjust the bi_sector to point the beginning of
> the zone.
> 
> Second, it records returned physical address (and disk/partno) to
> the ordered extent in end_bio_extent_writepage().

That sounds fishy ...

> Finally, it rewrites logical addresses of the extent mapping and checksum
> data according to the physical address (using __btrfs_rmap_block). If the
> returned address match to the originaly allocated address, we can skip the
> rewriting process.
> 
> [Johannes] fixed bvec handling
> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>

> --- a/fs/btrfs/ordered-data.h
> +++ b/fs/btrfs/ordered-data.h
> @@ -127,6 +127,10 @@ struct btrfs_ordered_extent {
>  	struct completion completion;
>  	struct btrfs_work flush_work;
>  	struct list_head work_list;
> +
> +	u64 physical;
> +	struct gendisk *disk;
> +	u8 partno;

btrfs_ordered_extent is on the logical layer, disk/partno is physical.

This needs proper explanation why it has to be done that way and that
there's not really anything better than layering violation.  Why
__btrfs_rmap_block takes bdev is unexplained.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 38/41] btrfs: extend zoned allocator to use dedicated tree-log block group
  2020-10-13 16:26     ` David Sterba
@ 2020-10-15  7:21       ` Johannes Thumshirn
  0 siblings, 0 replies; 60+ messages in thread
From: Johannes Thumshirn @ 2020-10-15  7:21 UTC (permalink / raw)
  To: dsterba, Naohiro Aota; +Cc: linux-btrfs, dsterba, hare, linux-fsdevel

On 13/10/2020 18:27, David Sterba wrote:
> On Fri, Oct 02, 2020 at 03:36:45AM +0900, Naohiro Aota wrote:
>> --- a/fs/btrfs/extent-tree.c
>> +++ b/fs/btrfs/extent-tree.c
>> @@ -3656,6 +3656,9 @@ struct find_free_extent_ctl {
>>  
>>  	/* Allocation policy */
>>  	enum btrfs_extent_allocation_policy policy;
>> +
>> +	/* Allocation is called for tree-log */
>> +	bool for_treelog;
> 
> There are already bool flags in find_free_extent_ctl, move it after
> orig_have_caching_bg.
> 

Fixed 

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 03/41] btrfs: Get zone information of zoned block devices
  2020-10-13 15:53     ` David Sterba
@ 2020-10-15  7:45       ` Johannes Thumshirn
  0 siblings, 0 replies; 60+ messages in thread
From: Johannes Thumshirn @ 2020-10-15  7:45 UTC (permalink / raw)
  To: dsterba, Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik, Damien Le Moal

On 13/10/2020 17:54, David Sterba wrote:
> On Fri, Oct 02, 2020 at 03:36:10AM +0900, Naohiro Aota wrote:
>> --- 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
> 
> As this is conditionally built in, it should be also added to the string
> printed by btrfs_print_mod_info and we want the actual status so
> 
> #ifdef CONFIG_BLK_DEV_ZONED
> 	", zoned=yes"
> #else
> 	", zoned=no"
> #endif
> 

done

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 07/41] btrfs: disallow NODATACOW in ZONED mode
  2020-10-13 15:39     ` David Sterba
@ 2020-10-21  8:53       ` Johannes Thumshirn
  0 siblings, 0 replies; 60+ messages in thread
From: Johannes Thumshirn @ 2020-10-21  8:53 UTC (permalink / raw)
  To: dsterba, Naohiro Aota
  Cc: linux-btrfs, dsterba, hare, linux-fsdevel, Johannes Thumshirn,
	Josef Bacik

On 13/10/2020 17:40, David Sterba wrote:
> This can't be inside the function, the 'type' here is for inode that
> does not know anything about zoned mode. The right place is after
> check_fsflags in btrfs_ioctl_setflags in a helper like:
> 
> 	ret = check_fsflags_compatible(fs_info, flags));
> 	if (ret)
> 		goto out_unlock;
> 
> and check_fsflags_compatible checks for zoned mode and NOCOW and returns
> -EPERM, not silently unmasking it.

And done as well.

^ permalink raw reply	[flat|nested] 60+ messages in thread

* Re: [PATCH v8 10/41] btrfs: disallow inode_cache in ZONED mode
  2020-10-13 15:41     ` David Sterba
@ 2020-10-22  6:48       ` Naohiro Aota
  0 siblings, 0 replies; 60+ messages in thread
From: Naohiro Aota @ 2020-10-22  6:48 UTC (permalink / raw)
  To: dsterba, linux-btrfs, dsterba, hare, linux-fsdevel, Josef Bacik

On Tue, Oct 13, 2020 at 05:41:17PM +0200, David Sterba wrote:
>On Fri, Oct 02, 2020 at 03:36:17AM +0900, Naohiro Aota wrote:
>> inode_cache use pre-allocation to write its cache data. However,
>> pre-allocation is completely disabled in ZONED mode.
>>
>> We can technically enable inode_cache in the same way as relocation.
>> However, inode_cache is rarely used and the man page discourage using it.
>> So, let's just disable it for now.
>
>Don't worry about the inode_cache mount option, it's been deprecated
>as of commit b547a88ea5776a8092f7 and will be removed in 5.11.

Thanks. I'll drop this one in the next version.

^ permalink raw reply	[flat|nested] 60+ messages in thread

end of thread, back to index

Thread overview: 60+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
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   ` [PATCH v8 03/41] btrfs: Get zone information of zoned block devices Naohiro Aota
2020-10-13 15:53     ` 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
2020-10-13 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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