WSL2-Linux-Kernel/Documentation/filesystems
Aravind Ramesh de881df977 f2fs: support zone capacity less than zone size
NVMe Zoned Namespace devices can have zone-capacity less than zone-size.
Zone-capacity indicates the maximum number of sectors that are usable in
a zone beginning from the first sector of the zone. This makes the sectors
sectors after the zone-capacity till zone-size to be unusable.
This patch set tracks zone-size and zone-capacity in zoned devices and
calculate the usable blocks per segment and usable segments per section.

If zone-capacity is less than zone-size mark only those segments which
start before zone-capacity as free segments. All segments at and beyond
zone-capacity are treated as permanently used segments. In cases where
zone-capacity does not align with segment size the last segment will start
before zone-capacity and end beyond the zone-capacity of the zone. For
such spanning segments only sectors within the zone-capacity are used.

During writes and GC manage the usable segments in a section and usable
blocks per segment. Segments which are beyond zone-capacity are never
allocated, and do not need to be garbage collected, only the segments
which are before zone-capacity needs to garbage collected.
For spanning segments based on the number of usable blocks in that
segment, write to blocks only up to zone-capacity.

Zone-capacity is device specific and cannot be configured by the user.
Since NVMe ZNS device zones are sequentially write only, a block device
with conventional zones or any normal block device is needed along with
the ZNS device for the metadata operations of F2fs.

A typical nvme-cli output of a zoned device shows zone start and capacity
and write pointer as below:

SLBA: 0x0     WP: 0x0     Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ
SLBA: 0x20000 WP: 0x20000 Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ
SLBA: 0x40000 WP: 0x40000 Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ

Here zone size is 64MB, capacity is 49MB, WP is at zone start as the zones
are in EMPTY state. For each zone, only zone start + 49MB is usable area,
any lba/sector after 49MB cannot be read or written to, the drive will fail
any attempts to read/write. So, the second zone starts at 64MB and is
usable till 113MB (64 + 49) and the range between 113 and 128MB is
again unusable. The next zone starts at 128MB, and so on.

Signed-off-by: Aravind Ramesh <aravind.ramesh@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-09-10 14:03:29 -07:00
..
caching docs: filesystems: Replace HTTP links with HTTPS ones 2020-07-13 09:33:22 -06:00
cifs docs: filesystems: convert cifs/cifsroot.txt to ReST 2020-05-05 09:22:21 -06:00
ext4 ext4: replace HTTP links with HTTPS ones 2020-08-06 01:01:57 -04:00
nfs Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
spufs docs: filesystems: convert spufs/spu_run.txt to ReST 2020-05-05 09:22:24 -06:00
9p.rst Replace HTTP links with HTTPS ones: 9P FILE SYSTEM 2020-07-13 11:28:12 -06:00
adfs.rst docs: filesystems: convert adfs.txt to ReST 2020-03-02 13:58:44 -07:00
affs.rst affs: fix basic permission bits to actually work 2020-08-31 12:20:31 +02:00
afs.rst Replace HTTP links with HTTPS ones: AFS FILESYSTEM 2020-07-13 11:25:29 -06:00
api-summary.rst docs: no structured comments in fs/file_table.c 2019-05-24 15:03:39 -06:00
autofs-mount-control.rst Documentation: filesystems: autofs-mount-control: drop doubled words 2020-07-05 14:44:29 -06:00
autofs.rst docs: filesystems: Add mount map description in Content 2019-11-18 12:19:59 -07:00
automount-support.rst docs: filesystems: convert automount-support.txt to ReST 2020-05-05 09:22:21 -06:00
befs.rst docs: filesystems: convert befs.txt to ReST 2020-03-02 14:01:25 -07:00
bfs.rst docs: filesystems: convert bfs.txt to ReST 2020-03-02 14:01:26 -07:00
btrfs.rst docs: filesystems: convert btrfs.txt to ReST 2020-03-02 14:01:28 -07:00
ceph.rst The main items are: 2020-04-08 21:44:05 -07:00
coda.rst Documentation: coda: annotate duplicated words 2020-07-13 10:02:32 -06:00
configfs.rst Documentation: filesystems: configfs: drop doubled word 2020-07-05 14:44:29 -06:00
cramfs.rst docs: filesystems: convert cramfs.txt to ReST 2020-03-02 14:02:07 -07:00
dax.txt This is the second round of ext4 commits for 5.8 merge window. It 2020-06-15 09:32:10 -07:00
debugfs.rst debugfs: make sure we can remove u32_array files cleanly 2020-07-10 13:54:00 -07:00
devpts.rst docs: filesystems: convert devpts.txt to ReST 2020-05-05 09:22:21 -06:00
directory-locking.rst Documentation: filesystems: directory-locking: drop doubled word 2020-07-05 14:44:29 -06:00
dlmfs.rst ocfs2: replace HTTP links with HTTPS ones 2020-08-07 11:33:22 -07:00
dnotify.rst docs: filesystems: convert dnotify.txt to ReST 2020-05-05 09:22:22 -06:00
ecryptfs.rst docs: prevent warnings due to autosectionlabel 2020-03-20 17:01:29 -06:00
efivarfs.rst docs: filesystems: add info about efivars content 2020-05-25 18:59:59 -06:00
erofs.rst docs: filesystems: convert erofs.txt to ReST 2020-03-02 14:02:57 -07:00
ext2.rst docs: filesystems: convert ext2.txt to ReST 2020-03-02 14:02:59 -07:00
ext3.rst docs: filesystems: convert ext3.txt to ReST 2020-03-02 14:03:16 -07:00
f2fs.rst f2fs: support zone capacity less than zone size 2020-09-10 14:03:29 -07:00
fiemap.rst A lot of bug fixes and cleanups for ext4, including: 2020-06-05 16:19:28 -07:00
files.rst docs: filesystems: convert files.txt to ReST 2020-05-05 09:22:22 -06:00
fscrypt.rst fscrypt: document inline encryption support 2020-07-27 09:18:49 -07:00
fsverity.rst Documentation: filesystems: fsverity: drop doubled word 2020-07-05 14:44:29 -06:00
fuse-io.rst docs: filesystems: convert fuse-io.txt to ReST 2020-05-05 09:22:22 -06:00
fuse.rst docs: filesystems: fuse.rst: supress a Sphinx warning 2020-03-10 11:55:25 -06:00
gfs2-glocks.rst docs: filesystems: convert gfs2-glocks.txt to ReST 2020-06-02 19:45:05 +02:00
gfs2-uevents.rst docs: filesystems: convert gfs2-uevents.txt to ReST 2020-03-02 14:03:35 -07:00
gfs2.rst docs: filesystems: convert gfs2.txt to ReST 2020-03-02 14:03:18 -07:00
hfs.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
hfsplus.rst docs: filesystems: convert hfsplus.txt to ReST 2020-03-02 14:03:47 -07:00
hpfs.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
index.rst Changes in gfs2: 2020-06-08 12:47:09 -07:00
inotify.rst docs: filesystems: convert inotify.txt to ReST 2020-03-02 14:03:55 -07:00
isofs.rst docs: filesystems: convert isofs.txt to ReST 2020-03-02 14:04:06 -07:00
journalling.rst Filesystems: Documentation: Replace deprecated :c:func: Usage 2020-08-11 10:23:27 -06:00
locking.rst It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
locks.rst docs: filesystems: convert mandatory-locking.txt to ReST 2020-05-05 09:22:22 -06:00
mandatory-locking.rst docs: filesystems: convert mandatory-locking.txt to ReST 2020-05-05 09:22:22 -06:00
mount_api.rst Documentation: filesystems: mount_api: drop doubled word 2020-07-05 14:44:29 -06:00
nilfs2.rst docs: filesystems: convert nilfs2.txt to ReST 2020-03-02 14:04:06 -07:00
ntfs.rst docs: filesystems: convert ntfs.txt to ReST 2020-03-02 14:04:06 -07:00
ocfs2-online-filecheck.rst docs: filesystems: convert ocfs2-online-filecheck.txt to ReST 2020-03-02 14:04:06 -07:00
ocfs2.rst ocfs2: replace HTTP links with HTTPS ones 2020-08-07 11:33:22 -07:00
omfs.rst Replace HTTP links with HTTPS ones: OMFS 2020-07-13 11:24:43 -06:00
orangefs.rst docs: orangefs: fix pvfs2tab literal block 2020-04-28 12:35:47 -06:00
overlayfs.rst It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
path-lookup.rst docs: path-lookup: markup fixes for emphasis 2020-07-27 16:14:13 -06:00
path-lookup.txt Replace HTTP links with HTTPS ones: documentation 2020-06-08 09:30:19 -06:00
porting.rst ovl: make private mounts longterm 2020-06-04 10:48:19 +02:00
proc.rst doc, mm: clarify /proc/<pid>/oom_score value range 2020-08-12 10:57:56 -07:00
qnx6.rst docs: filesystems: fix typo in qnx6.rst 2020-04-07 13:20:56 -06:00
quota.rst quota: Fixup http links in quota doc 2020-07-09 08:14:01 +02:00
ramfs-rootfs-initramfs.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
relay.rst docs: filesystems: convert relay.txt to ReST 2020-03-02 14:04:41 -07:00
romfs.rst docs: filesystems: convert romfs.txt to ReST 2020-03-02 14:04:41 -07:00
seq_file.rst Replace HTTP links with HTTPS ones: documentation 2020-06-08 09:30:19 -06:00
sharedsubtree.rst docs: filesystems: convert sharedsubtree.txt to ReST 2020-05-05 09:22:23 -06:00
splice.rst docs: Bring some order to filesystem documentation 2019-03-06 09:46:10 -07:00
squashfs.rst docs: filesystems: convert squashfs.txt to ReST 2020-03-02 14:04:41 -07:00
sysfs-pci.rst PCI: correct flag name 2020-07-27 16:21:04 -06:00
sysfs-tagging.rst Documentation: filesystems: sysfs-tagging: drop doubled word 2020-07-05 14:44:30 -06:00
sysfs.rst docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
sysv-fs.rst docs: filesystems: convert sysv-fs.txt to ReST 2020-03-02 14:04:41 -07:00
tmpfs.rst tmpfs: support 64-bit inums per-sb 2020-08-07 11:33:24 -07:00
ubifs-authentication.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
ubifs.rst docs: filesystems: convert ubifs.txt to ReST 2020-03-02 14:04:41 -07:00
udf.rst udf: Replace HTTP links with HTTPS ones 2020-07-14 14:37:39 +02:00
vfat.rst Documentation: filesystems: convert vfat.txt to RST 2020-01-10 10:58:45 -07:00
vfs.rst docs: filesystems: vfs: correct flag name 2020-07-27 16:19:51 -06:00
virtiofs.rst virtiofs: Add mount option and atime behavior to the doc 2020-04-20 17:01:34 +02:00
xfs-delayed-logging-design.rst docs: filesystems: convert xfs-delayed-logging-design.txt to ReST 2020-05-05 09:22:24 -06:00
xfs-self-describing-metadata.rst New code for 5.8: 2020-06-02 19:21:40 -07:00
zonefs.rst zonefs: update documentation to reflect zone size vs capacity 2020-08-11 17:42:25 +09:00