dm zoned: drive-managed zoned block device target
The dm-zoned device mapper target provides transparent write access to zoned block devices (ZBC and ZAC compliant block devices). dm-zoned hides to the device user (a file system or an application doing raw block device accesses) any constraint imposed on write requests by the device, equivalent to a drive-managed zoned block device model. Write requests are processed using a combination of on-disk buffering using the device conventional zones and direct in-place processing for requests aligned to a zone sequential write pointer position. A background reclaim process implemented using dm_kcopyd_copy ensures that conventional zones are always available for executing unaligned write requests. The reclaim process overhead is minimized by managing buffer zones in a least-recently-written order and first targeting the oldest buffer zones. Doing so, blocks under regular write access (such as metadata blocks of a file system) remain stored in conventional zones, resulting in no apparent overhead. dm-zoned implementation focus on simplicity and on minimizing overhead (CPU, memory and storage overhead). For a 14TB host-managed disk with 256 MB zones, dm-zoned memory usage per disk instance is at most about 3 MB and as little as 5 zones will be used internally for storing metadata and performing buffer zone reclaim operations. This is achieved using zone level indirection rather than a full block indirection system for managing block movement between zones. dm-zoned primary target is host-managed zoned block devices but it can also be used with host-aware device models to mitigate potential device-side performance degradation due to excessive random writing. Zoned block devices can be formatted and checked for use with the dm-zoned target using the dmzadm utility available at: https://github.com/hgst/dm-zoned-tools Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> [Mike Snitzer partly refactored Damien's original work to cleanup the code] Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Documentation/device-mapper/dm-zoned.txt
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Documentation/device-mapper/dm-zoned.txt
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dm-zoned
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========
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The dm-zoned device mapper target exposes a zoned block device (ZBC and
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ZAC compliant devices) as a regular block device without any write
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pattern constraints. In effect, it implements a drive-managed zoned
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block device which hides from the user (a file system or an application
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doing raw block device accesses) the sequential write constraints of
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host-managed zoned block devices and can mitigate the potential
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device-side performance degradation due to excessive random writes on
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host-aware zoned block devices.
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For a more detailed description of the zoned block device models and
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their constraints see (for SCSI devices):
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http://www.t10.org/drafts.htm#ZBC_Family
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and (for ATA devices):
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http://www.t13.org/Documents/UploadedDocuments/docs2015/di537r05-Zoned_Device_ATA_Command_Set_ZAC.pdf
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The dm-zoned implementation is simple and minimizes system overhead (CPU
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and memory usage as well as storage capacity loss). For a 10TB
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host-managed disk with 256 MB zones, dm-zoned memory usage per disk
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instance is at most 4.5 MB and as little as 5 zones will be used
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internally for storing metadata and performaing reclaim operations.
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dm-zoned target devices are formatted and checked using the dmzadm
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utility available at:
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https://github.com/hgst/dm-zoned-tools
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Algorithm
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=========
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dm-zoned implements an on-disk buffering scheme to handle non-sequential
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write accesses to the sequential zones of a zoned block device.
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Conventional zones are used for caching as well as for storing internal
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metadata.
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The zones of the device are separated into 2 types:
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1) Metadata zones: these are conventional zones used to store metadata.
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Metadata zones are not reported as useable capacity to the user.
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2) Data zones: all remaining zones, the vast majority of which will be
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sequential zones used exclusively to store user data. The conventional
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zones of the device may be used also for buffering user random writes.
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Data in these zones may be directly mapped to the conventional zone, but
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later moved to a sequential zone so that the conventional zone can be
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reused for buffering incoming random writes.
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dm-zoned exposes a logical device with a sector size of 4096 bytes,
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irrespective of the physical sector size of the backend zoned block
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device being used. This allows reducing the amount of metadata needed to
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manage valid blocks (blocks written).
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The on-disk metadata format is as follows:
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1) The first block of the first conventional zone found contains the
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super block which describes the on disk amount and position of metadata
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blocks.
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2) Following the super block, a set of blocks is used to describe the
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mapping of the logical device blocks. The mapping is done per chunk of
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blocks, with the chunk size equal to the zoned block device size. The
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mapping table is indexed by chunk number and each mapping entry
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indicates the zone number of the device storing the chunk of data. Each
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mapping entry may also indicate if the zone number of a conventional
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zone used to buffer random modification to the data zone.
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3) A set of blocks used to store bitmaps indicating the validity of
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blocks in the data zones follows the mapping table. A valid block is
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defined as a block that was written and not discarded. For a buffered
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data chunk, a block is always valid only in the data zone mapping the
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chunk or in the buffer zone of the chunk.
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For a logical chunk mapped to a conventional zone, all write operations
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are processed by directly writing to the zone. If the mapping zone is a
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sequential zone, the write operation is processed directly only if the
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write offset within the logical chunk is equal to the write pointer
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offset within of the sequential data zone (i.e. the write operation is
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aligned on the zone write pointer). Otherwise, write operations are
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processed indirectly using a buffer zone. In that case, an unused
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conventional zone is allocated and assigned to the chunk being
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accessed. Writing a block to the buffer zone of a chunk will
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automatically invalidate the same block in the sequential zone mapping
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the chunk. If all blocks of the sequential zone become invalid, the zone
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is freed and the chunk buffer zone becomes the primary zone mapping the
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chunk, resulting in native random write performance similar to a regular
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block device.
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Read operations are processed according to the block validity
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information provided by the bitmaps. Valid blocks are read either from
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the sequential zone mapping a chunk, or if the chunk is buffered, from
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the buffer zone assigned. If the accessed chunk has no mapping, or the
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accessed blocks are invalid, the read buffer is zeroed and the read
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operation terminated.
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After some time, the limited number of convnetional zones available may
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be exhausted (all used to map chunks or buffer sequential zones) and
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unaligned writes to unbuffered chunks become impossible. To avoid this
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situation, a reclaim process regularly scans used conventional zones and
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tries to reclaim the least recently used zones by copying the valid
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blocks of the buffer zone to a free sequential zone. Once the copy
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completes, the chunk mapping is updated to point to the sequential zone
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and the buffer zone freed for reuse.
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Metadata Protection
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===================
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To protect metadata against corruption in case of sudden power loss or
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system crash, 2 sets of metadata zones are used. One set, the primary
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set, is used as the main metadata region, while the secondary set is
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used as a staging area. Modified metadata is first written to the
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secondary set and validated by updating the super block in the secondary
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set, a generation counter is used to indicate that this set contains the
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newest metadata. Once this operation completes, in place of metadata
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block updates can be done in the primary metadata set. This ensures that
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one of the set is always consistent (all modifications committed or none
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at all). Flush operations are used as a commit point. Upon reception of
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a flush request, metadata modification activity is temporarily blocked
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(for both incoming BIO processing and reclaim process) and all dirty
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metadata blocks are staged and updated. Normal operation is then
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resumed. Flushing metadata thus only temporarily delays write and
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discard requests. Read requests can be processed concurrently while
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metadata flush is being executed.
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Usage
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=====
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A zoned block device must first be formatted using the dmzadm tool. This
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will analyze the device zone configuration, determine where to place the
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metadata sets on the device and initialize the metadata sets.
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Ex:
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dmzadm --format /dev/sdxx
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For a formatted device, the target can be created normally with the
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dmsetup utility. The only parameter that dm-zoned requires is the
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underlying zoned block device name. Ex:
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echo "0 `blockdev --getsize ${dev}` zoned ${dev}" | dmsetup create dmz-`basename ${dev}`
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@ -521,6 +521,23 @@ config DM_INTEGRITY
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To compile this code as a module, choose M here: the module will
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be called dm-integrity.
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config DM_ZONED
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tristate "Drive-managed zoned block device target support"
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depends on BLK_DEV_DM
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depends on BLK_DEV_ZONED
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---help---
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This device-mapper target takes a host-managed or host-aware zoned
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block device and exposes most of its capacity as a regular block
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device (drive-managed zoned block device) without any write
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constraints. This is mainly intended for use with file systems that
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do not natively support zoned block devices but still want to
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benefit from the increased capacity offered by SMR disks. Other uses
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by applications using raw block devices (for example object stores)
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are also possible.
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To compile this code as a module, choose M here: the module will
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be called dm-zoned.
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If unsure, say N.
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endif # MD
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@ -20,6 +20,7 @@ dm-era-y += dm-era-target.o
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dm-verity-y += dm-verity-target.o
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md-mod-y += md.o bitmap.o
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raid456-y += raid5.o raid5-cache.o raid5-ppl.o
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dm-zoned-y += dm-zoned-target.o dm-zoned-metadata.o dm-zoned-reclaim.o
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# Note: link order is important. All raid personalities
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# and must come before md.o, as they each initialise
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@ -60,6 +61,7 @@ obj-$(CONFIG_DM_CACHE_SMQ) += dm-cache-smq.o
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obj-$(CONFIG_DM_ERA) += dm-era.o
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obj-$(CONFIG_DM_LOG_WRITES) += dm-log-writes.o
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obj-$(CONFIG_DM_INTEGRITY) += dm-integrity.o
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obj-$(CONFIG_DM_ZONED) += dm-zoned.o
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ifeq ($(CONFIG_DM_UEVENT),y)
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dm-mod-objs += dm-uevent.o
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2509
drivers/md/dm-zoned-metadata.c
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2509
drivers/md/dm-zoned-metadata.c
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File diff suppressed because it is too large
Load diff
570
drivers/md/dm-zoned-reclaim.c
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570
drivers/md/dm-zoned-reclaim.c
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/*
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* Copyright (C) 2017 Western Digital Corporation or its affiliates.
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*
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* This file is released under the GPL.
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*/
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#include "dm-zoned.h"
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#include <linux/module.h>
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#define DM_MSG_PREFIX "zoned reclaim"
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struct dmz_reclaim {
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struct dmz_metadata *metadata;
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struct dmz_dev *dev;
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struct delayed_work work;
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struct workqueue_struct *wq;
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struct dm_kcopyd_client *kc;
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struct dm_kcopyd_throttle kc_throttle;
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int kc_err;
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unsigned long flags;
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/* Last target access time */
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unsigned long atime;
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};
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/*
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* Reclaim state flags.
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*/
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enum {
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DMZ_RECLAIM_KCOPY,
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};
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/*
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* Number of seconds of target BIO inactivity to consider the target idle.
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*/
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#define DMZ_IDLE_PERIOD (10UL * HZ)
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/*
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* Percentage of unmapped (free) random zones below which reclaim starts
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* even if the target is busy.
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*/
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#define DMZ_RECLAIM_LOW_UNMAP_RND 30
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/*
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* Percentage of unmapped (free) random zones above which reclaim will
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* stop if the target is busy.
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*/
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#define DMZ_RECLAIM_HIGH_UNMAP_RND 50
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/*
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* Align a sequential zone write pointer to chunk_block.
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*/
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static int dmz_reclaim_align_wp(struct dmz_reclaim *zrc, struct dm_zone *zone,
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sector_t block)
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{
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struct dmz_metadata *zmd = zrc->metadata;
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sector_t wp_block = zone->wp_block;
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unsigned int nr_blocks;
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int ret;
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if (wp_block == block)
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return 0;
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if (wp_block > block)
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return -EIO;
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/*
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* Zeroout the space between the write
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* pointer and the requested position.
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*/
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nr_blocks = block - wp_block;
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ret = blkdev_issue_zeroout(zrc->dev->bdev,
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dmz_start_sect(zmd, zone) + dmz_blk2sect(wp_block),
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dmz_blk2sect(nr_blocks), GFP_NOFS, false);
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if (ret) {
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dmz_dev_err(zrc->dev,
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"Align zone %u wp %llu to %llu (wp+%u) blocks failed %d",
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dmz_id(zmd, zone), (unsigned long long)wp_block,
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(unsigned long long)block, nr_blocks, ret);
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return ret;
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}
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zone->wp_block = block;
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return 0;
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}
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/*
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* dm_kcopyd_copy end notification.
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*/
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static void dmz_reclaim_kcopy_end(int read_err, unsigned long write_err,
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void *context)
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{
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struct dmz_reclaim *zrc = context;
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if (read_err || write_err)
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zrc->kc_err = -EIO;
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else
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zrc->kc_err = 0;
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clear_bit_unlock(DMZ_RECLAIM_KCOPY, &zrc->flags);
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smp_mb__after_atomic();
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wake_up_bit(&zrc->flags, DMZ_RECLAIM_KCOPY);
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}
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/*
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* Copy valid blocks of src_zone into dst_zone.
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*/
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static int dmz_reclaim_copy(struct dmz_reclaim *zrc,
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struct dm_zone *src_zone, struct dm_zone *dst_zone)
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{
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struct dmz_metadata *zmd = zrc->metadata;
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struct dmz_dev *dev = zrc->dev;
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struct dm_io_region src, dst;
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sector_t block = 0, end_block;
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sector_t nr_blocks;
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sector_t src_zone_block;
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sector_t dst_zone_block;
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unsigned long flags = 0;
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int ret;
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if (dmz_is_seq(src_zone))
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end_block = src_zone->wp_block;
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else
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end_block = dev->zone_nr_blocks;
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src_zone_block = dmz_start_block(zmd, src_zone);
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dst_zone_block = dmz_start_block(zmd, dst_zone);
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if (dmz_is_seq(dst_zone))
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set_bit(DM_KCOPYD_WRITE_SEQ, &flags);
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while (block < end_block) {
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/* Get a valid region from the source zone */
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ret = dmz_first_valid_block(zmd, src_zone, &block);
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if (ret <= 0)
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return ret;
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nr_blocks = ret;
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/*
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* If we are writing in a sequential zone, we must make sure
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* that writes are sequential. So Zeroout any eventual hole
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* between writes.
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*/
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if (dmz_is_seq(dst_zone)) {
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ret = dmz_reclaim_align_wp(zrc, dst_zone, block);
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if (ret)
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return ret;
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}
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src.bdev = dev->bdev;
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src.sector = dmz_blk2sect(src_zone_block + block);
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src.count = dmz_blk2sect(nr_blocks);
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dst.bdev = dev->bdev;
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dst.sector = dmz_blk2sect(dst_zone_block + block);
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dst.count = src.count;
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/* Copy the valid region */
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set_bit(DMZ_RECLAIM_KCOPY, &zrc->flags);
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ret = dm_kcopyd_copy(zrc->kc, &src, 1, &dst, flags,
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dmz_reclaim_kcopy_end, zrc);
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if (ret)
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return ret;
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/* Wait for copy to complete */
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wait_on_bit_io(&zrc->flags, DMZ_RECLAIM_KCOPY,
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TASK_UNINTERRUPTIBLE);
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if (zrc->kc_err)
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return zrc->kc_err;
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block += nr_blocks;
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if (dmz_is_seq(dst_zone))
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dst_zone->wp_block = block;
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}
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return 0;
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}
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/*
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* Move valid blocks of dzone buffer zone into dzone (after its write pointer)
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* and free the buffer zone.
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*/
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static int dmz_reclaim_buf(struct dmz_reclaim *zrc, struct dm_zone *dzone)
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{
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struct dm_zone *bzone = dzone->bzone;
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sector_t chunk_block = dzone->wp_block;
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struct dmz_metadata *zmd = zrc->metadata;
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int ret;
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dmz_dev_debug(zrc->dev,
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"Chunk %u, move buf zone %u (weight %u) to data zone %u (weight %u)",
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dzone->chunk, dmz_id(zmd, bzone), dmz_weight(bzone),
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dmz_id(zmd, dzone), dmz_weight(dzone));
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/* Flush data zone into the buffer zone */
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ret = dmz_reclaim_copy(zrc, bzone, dzone);
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if (ret < 0)
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return ret;
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dmz_lock_flush(zmd);
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/* Validate copied blocks */
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ret = dmz_merge_valid_blocks(zmd, bzone, dzone, chunk_block);
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if (ret == 0) {
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/* Free the buffer zone */
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dmz_invalidate_blocks(zmd, bzone, 0, zrc->dev->zone_nr_blocks);
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dmz_lock_map(zmd);
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dmz_unmap_zone(zmd, bzone);
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dmz_unlock_zone_reclaim(dzone);
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dmz_free_zone(zmd, bzone);
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dmz_unlock_map(zmd);
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}
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dmz_unlock_flush(zmd);
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return 0;
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}
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/*
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* Merge valid blocks of dzone into its buffer zone and free dzone.
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*/
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static int dmz_reclaim_seq_data(struct dmz_reclaim *zrc, struct dm_zone *dzone)
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{
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unsigned int chunk = dzone->chunk;
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struct dm_zone *bzone = dzone->bzone;
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struct dmz_metadata *zmd = zrc->metadata;
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int ret = 0;
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dmz_dev_debug(zrc->dev,
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"Chunk %u, move data zone %u (weight %u) to buf zone %u (weight %u)",
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chunk, dmz_id(zmd, dzone), dmz_weight(dzone),
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dmz_id(zmd, bzone), dmz_weight(bzone));
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/* Flush data zone into the buffer zone */
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ret = dmz_reclaim_copy(zrc, dzone, bzone);
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if (ret < 0)
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return ret;
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|
||||
dmz_lock_flush(zmd);
|
||||
|
||||
/* Validate copied blocks */
|
||||
ret = dmz_merge_valid_blocks(zmd, dzone, bzone, 0);
|
||||
if (ret == 0) {
|
||||
/*
|
||||
* Free the data zone and remap the chunk to
|
||||
* the buffer zone.
|
||||
*/
|
||||
dmz_invalidate_blocks(zmd, dzone, 0, zrc->dev->zone_nr_blocks);
|
||||
dmz_lock_map(zmd);
|
||||
dmz_unmap_zone(zmd, bzone);
|
||||
dmz_unmap_zone(zmd, dzone);
|
||||
dmz_unlock_zone_reclaim(dzone);
|
||||
dmz_free_zone(zmd, dzone);
|
||||
dmz_map_zone(zmd, bzone, chunk);
|
||||
dmz_unlock_map(zmd);
|
||||
}
|
||||
|
||||
dmz_unlock_flush(zmd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Move valid blocks of the random data zone dzone into a free sequential zone.
|
||||
* Once blocks are moved, remap the zone chunk to the sequential zone.
|
||||
*/
|
||||
static int dmz_reclaim_rnd_data(struct dmz_reclaim *zrc, struct dm_zone *dzone)
|
||||
{
|
||||
unsigned int chunk = dzone->chunk;
|
||||
struct dm_zone *szone = NULL;
|
||||
struct dmz_metadata *zmd = zrc->metadata;
|
||||
int ret;
|
||||
|
||||
/* Get a free sequential zone */
|
||||
dmz_lock_map(zmd);
|
||||
szone = dmz_alloc_zone(zmd, DMZ_ALLOC_RECLAIM);
|
||||
dmz_unlock_map(zmd);
|
||||
if (!szone)
|
||||
return -ENOSPC;
|
||||
|
||||
dmz_dev_debug(zrc->dev,
|
||||
"Chunk %u, move rnd zone %u (weight %u) to seq zone %u",
|
||||
chunk, dmz_id(zmd, dzone), dmz_weight(dzone),
|
||||
dmz_id(zmd, szone));
|
||||
|
||||
/* Flush the random data zone into the sequential zone */
|
||||
ret = dmz_reclaim_copy(zrc, dzone, szone);
|
||||
|
||||
dmz_lock_flush(zmd);
|
||||
|
||||
if (ret == 0) {
|
||||
/* Validate copied blocks */
|
||||
ret = dmz_copy_valid_blocks(zmd, dzone, szone);
|
||||
}
|
||||
if (ret) {
|
||||
/* Free the sequential zone */
|
||||
dmz_lock_map(zmd);
|
||||
dmz_free_zone(zmd, szone);
|
||||
dmz_unlock_map(zmd);
|
||||
} else {
|
||||
/* Free the data zone and remap the chunk */
|
||||
dmz_invalidate_blocks(zmd, dzone, 0, zrc->dev->zone_nr_blocks);
|
||||
dmz_lock_map(zmd);
|
||||
dmz_unmap_zone(zmd, dzone);
|
||||
dmz_unlock_zone_reclaim(dzone);
|
||||
dmz_free_zone(zmd, dzone);
|
||||
dmz_map_zone(zmd, szone, chunk);
|
||||
dmz_unlock_map(zmd);
|
||||
}
|
||||
|
||||
dmz_unlock_flush(zmd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Reclaim an empty zone.
|
||||
*/
|
||||
static void dmz_reclaim_empty(struct dmz_reclaim *zrc, struct dm_zone *dzone)
|
||||
{
|
||||
struct dmz_metadata *zmd = zrc->metadata;
|
||||
|
||||
dmz_lock_flush(zmd);
|
||||
dmz_lock_map(zmd);
|
||||
dmz_unmap_zone(zmd, dzone);
|
||||
dmz_unlock_zone_reclaim(dzone);
|
||||
dmz_free_zone(zmd, dzone);
|
||||
dmz_unlock_map(zmd);
|
||||
dmz_unlock_flush(zmd);
|
||||
}
|
||||
|
||||
/*
|
||||
* Find a candidate zone for reclaim and process it.
|
||||
*/
|
||||
static void dmz_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
struct dmz_metadata *zmd = zrc->metadata;
|
||||
struct dm_zone *dzone;
|
||||
struct dm_zone *rzone;
|
||||
unsigned long start;
|
||||
int ret;
|
||||
|
||||
/* Get a data zone */
|
||||
dzone = dmz_get_zone_for_reclaim(zmd);
|
||||
if (!dzone)
|
||||
return;
|
||||
|
||||
start = jiffies;
|
||||
|
||||
if (dmz_is_rnd(dzone)) {
|
||||
if (!dmz_weight(dzone)) {
|
||||
/* Empty zone */
|
||||
dmz_reclaim_empty(zrc, dzone);
|
||||
ret = 0;
|
||||
} else {
|
||||
/*
|
||||
* Reclaim the random data zone by moving its
|
||||
* valid data blocks to a free sequential zone.
|
||||
*/
|
||||
ret = dmz_reclaim_rnd_data(zrc, dzone);
|
||||
}
|
||||
rzone = dzone;
|
||||
|
||||
} else {
|
||||
struct dm_zone *bzone = dzone->bzone;
|
||||
sector_t chunk_block = 0;
|
||||
|
||||
ret = dmz_first_valid_block(zmd, bzone, &chunk_block);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
|
||||
if (ret == 0 || chunk_block >= dzone->wp_block) {
|
||||
/*
|
||||
* The buffer zone is empty or its valid blocks are
|
||||
* after the data zone write pointer.
|
||||
*/
|
||||
ret = dmz_reclaim_buf(zrc, dzone);
|
||||
rzone = bzone;
|
||||
} else {
|
||||
/*
|
||||
* Reclaim the data zone by merging it into the
|
||||
* buffer zone so that the buffer zone itself can
|
||||
* be later reclaimed.
|
||||
*/
|
||||
ret = dmz_reclaim_seq_data(zrc, dzone);
|
||||
rzone = dzone;
|
||||
}
|
||||
}
|
||||
out:
|
||||
if (ret) {
|
||||
dmz_unlock_zone_reclaim(dzone);
|
||||
return;
|
||||
}
|
||||
|
||||
(void) dmz_flush_metadata(zrc->metadata);
|
||||
|
||||
dmz_dev_debug(zrc->dev, "Reclaimed zone %u in %u ms",
|
||||
dmz_id(zmd, rzone), jiffies_to_msecs(jiffies - start));
|
||||
}
|
||||
|
||||
/*
|
||||
* Test if the target device is idle.
|
||||
*/
|
||||
static inline int dmz_target_idle(struct dmz_reclaim *zrc)
|
||||
{
|
||||
return time_is_before_jiffies(zrc->atime + DMZ_IDLE_PERIOD);
|
||||
}
|
||||
|
||||
/*
|
||||
* Test if reclaim is necessary.
|
||||
*/
|
||||
static bool dmz_should_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
struct dmz_metadata *zmd = zrc->metadata;
|
||||
unsigned int nr_rnd = dmz_nr_rnd_zones(zmd);
|
||||
unsigned int nr_unmap_rnd = dmz_nr_unmap_rnd_zones(zmd);
|
||||
unsigned int p_unmap_rnd = nr_unmap_rnd * 100 / nr_rnd;
|
||||
|
||||
/* Reclaim when idle */
|
||||
if (dmz_target_idle(zrc) && nr_unmap_rnd < nr_rnd)
|
||||
return true;
|
||||
|
||||
/* If there are still plenty of random zones, do not reclaim */
|
||||
if (p_unmap_rnd >= DMZ_RECLAIM_HIGH_UNMAP_RND)
|
||||
return false;
|
||||
|
||||
/*
|
||||
* If the percentage of unmappped random zones is low,
|
||||
* reclaim even if the target is busy.
|
||||
*/
|
||||
return p_unmap_rnd <= DMZ_RECLAIM_LOW_UNMAP_RND;
|
||||
}
|
||||
|
||||
/*
|
||||
* Reclaim work function.
|
||||
*/
|
||||
static void dmz_reclaim_work(struct work_struct *work)
|
||||
{
|
||||
struct dmz_reclaim *zrc = container_of(work, struct dmz_reclaim, work.work);
|
||||
struct dmz_metadata *zmd = zrc->metadata;
|
||||
unsigned int nr_rnd, nr_unmap_rnd;
|
||||
unsigned int p_unmap_rnd;
|
||||
|
||||
if (!dmz_should_reclaim(zrc)) {
|
||||
mod_delayed_work(zrc->wq, &zrc->work, DMZ_IDLE_PERIOD);
|
||||
return;
|
||||
}
|
||||
|
||||
/*
|
||||
* We need to start reclaiming random zones: set up zone copy
|
||||
* throttling to either go fast if we are very low on random zones
|
||||
* and slower if there are still some free random zones to avoid
|
||||
* as much as possible to negatively impact the user workload.
|
||||
*/
|
||||
nr_rnd = dmz_nr_rnd_zones(zmd);
|
||||
nr_unmap_rnd = dmz_nr_unmap_rnd_zones(zmd);
|
||||
p_unmap_rnd = nr_unmap_rnd * 100 / nr_rnd;
|
||||
if (dmz_target_idle(zrc) || p_unmap_rnd < DMZ_RECLAIM_LOW_UNMAP_RND / 2) {
|
||||
/* Idle or very low percentage: go fast */
|
||||
zrc->kc_throttle.throttle = 100;
|
||||
} else {
|
||||
/* Busy but we still have some random zone: throttle */
|
||||
zrc->kc_throttle.throttle = min(75U, 100U - p_unmap_rnd / 2);
|
||||
}
|
||||
|
||||
dmz_dev_debug(zrc->dev,
|
||||
"Reclaim (%u): %s, %u%% free rnd zones (%u/%u)",
|
||||
zrc->kc_throttle.throttle,
|
||||
(dmz_target_idle(zrc) ? "Idle" : "Busy"),
|
||||
p_unmap_rnd, nr_unmap_rnd, nr_rnd);
|
||||
|
||||
dmz_reclaim(zrc);
|
||||
|
||||
dmz_schedule_reclaim(zrc);
|
||||
}
|
||||
|
||||
/*
|
||||
* Initialize reclaim.
|
||||
*/
|
||||
int dmz_ctr_reclaim(struct dmz_dev *dev, struct dmz_metadata *zmd,
|
||||
struct dmz_reclaim **reclaim)
|
||||
{
|
||||
struct dmz_reclaim *zrc;
|
||||
int ret;
|
||||
|
||||
zrc = kzalloc(sizeof(struct dmz_reclaim), GFP_KERNEL);
|
||||
if (!zrc)
|
||||
return -ENOMEM;
|
||||
|
||||
zrc->dev = dev;
|
||||
zrc->metadata = zmd;
|
||||
zrc->atime = jiffies;
|
||||
|
||||
/* Reclaim kcopyd client */
|
||||
zrc->kc = dm_kcopyd_client_create(&zrc->kc_throttle);
|
||||
if (IS_ERR(zrc->kc)) {
|
||||
ret = PTR_ERR(zrc->kc);
|
||||
zrc->kc = NULL;
|
||||
goto err;
|
||||
}
|
||||
|
||||
/* Reclaim work */
|
||||
INIT_DELAYED_WORK(&zrc->work, dmz_reclaim_work);
|
||||
zrc->wq = alloc_ordered_workqueue("dmz_rwq_%s", WQ_MEM_RECLAIM,
|
||||
dev->name);
|
||||
if (!zrc->wq) {
|
||||
ret = -ENOMEM;
|
||||
goto err;
|
||||
}
|
||||
|
||||
*reclaim = zrc;
|
||||
queue_delayed_work(zrc->wq, &zrc->work, 0);
|
||||
|
||||
return 0;
|
||||
err:
|
||||
if (zrc->kc)
|
||||
dm_kcopyd_client_destroy(zrc->kc);
|
||||
kfree(zrc);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Terminate reclaim.
|
||||
*/
|
||||
void dmz_dtr_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
cancel_delayed_work_sync(&zrc->work);
|
||||
destroy_workqueue(zrc->wq);
|
||||
dm_kcopyd_client_destroy(zrc->kc);
|
||||
kfree(zrc);
|
||||
}
|
||||
|
||||
/*
|
||||
* Suspend reclaim.
|
||||
*/
|
||||
void dmz_suspend_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
cancel_delayed_work_sync(&zrc->work);
|
||||
}
|
||||
|
||||
/*
|
||||
* Resume reclaim.
|
||||
*/
|
||||
void dmz_resume_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
queue_delayed_work(zrc->wq, &zrc->work, DMZ_IDLE_PERIOD);
|
||||
}
|
||||
|
||||
/*
|
||||
* BIO accounting.
|
||||
*/
|
||||
void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc)
|
||||
{
|
||||
zrc->atime = jiffies;
|
||||
}
|
||||
|
||||
/*
|
||||
* Start reclaim if necessary.
|
||||
*/
|
||||
void dmz_schedule_reclaim(struct dmz_reclaim *zrc)
|
||||
{
|
||||
if (dmz_should_reclaim(zrc))
|
||||
mod_delayed_work(zrc->wq, &zrc->work, 0);
|
||||
}
|
||||
|
967
drivers/md/dm-zoned-target.c
Normal file
967
drivers/md/dm-zoned-target.c
Normal file
|
@ -0,0 +1,967 @@
|
|||
/*
|
||||
* Copyright (C) 2017 Western Digital Corporation or its affiliates.
|
||||
*
|
||||
* This file is released under the GPL.
|
||||
*/
|
||||
|
||||
#include "dm-zoned.h"
|
||||
|
||||
#include <linux/module.h>
|
||||
|
||||
#define DM_MSG_PREFIX "zoned"
|
||||
|
||||
#define DMZ_MIN_BIOS 8192
|
||||
|
||||
/*
|
||||
* Zone BIO context.
|
||||
*/
|
||||
struct dmz_bioctx {
|
||||
struct dmz_target *target;
|
||||
struct dm_zone *zone;
|
||||
struct bio *bio;
|
||||
atomic_t ref;
|
||||
blk_status_t status;
|
||||
};
|
||||
|
||||
/*
|
||||
* Chunk work descriptor.
|
||||
*/
|
||||
struct dm_chunk_work {
|
||||
struct work_struct work;
|
||||
atomic_t refcount;
|
||||
struct dmz_target *target;
|
||||
unsigned int chunk;
|
||||
struct bio_list bio_list;
|
||||
};
|
||||
|
||||
/*
|
||||
* Target descriptor.
|
||||
*/
|
||||
struct dmz_target {
|
||||
struct dm_dev *ddev;
|
||||
|
||||
unsigned long flags;
|
||||
|
||||
/* Zoned block device information */
|
||||
struct dmz_dev *dev;
|
||||
|
||||
/* For metadata handling */
|
||||
struct dmz_metadata *metadata;
|
||||
|
||||
/* For reclaim */
|
||||
struct dmz_reclaim *reclaim;
|
||||
|
||||
/* For chunk work */
|
||||
struct mutex chunk_lock;
|
||||
struct radix_tree_root chunk_rxtree;
|
||||
struct workqueue_struct *chunk_wq;
|
||||
|
||||
/* For cloned BIOs to zones */
|
||||
struct bio_set *bio_set;
|
||||
|
||||
/* For flush */
|
||||
spinlock_t flush_lock;
|
||||
struct bio_list flush_list;
|
||||
struct delayed_work flush_work;
|
||||
struct workqueue_struct *flush_wq;
|
||||
};
|
||||
|
||||
/*
|
||||
* Flush intervals (seconds).
|
||||
*/
|
||||
#define DMZ_FLUSH_PERIOD (10 * HZ)
|
||||
|
||||
/*
|
||||
* Target BIO completion.
|
||||
*/
|
||||
static inline void dmz_bio_endio(struct bio *bio, blk_status_t status)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
|
||||
if (bioctx->status == BLK_STS_OK && status != BLK_STS_OK)
|
||||
bioctx->status = status;
|
||||
bio_endio(bio);
|
||||
}
|
||||
|
||||
/*
|
||||
* Partial clone read BIO completion callback. This terminates the
|
||||
* target BIO when there are no more references to its context.
|
||||
*/
|
||||
static void dmz_read_bio_end_io(struct bio *bio)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = bio->bi_private;
|
||||
blk_status_t status = bio->bi_status;
|
||||
|
||||
bio_put(bio);
|
||||
dmz_bio_endio(bioctx->bio, status);
|
||||
}
|
||||
|
||||
/*
|
||||
* Issue a BIO to a zone. The BIO may only partially process the
|
||||
* original target BIO.
|
||||
*/
|
||||
static int dmz_submit_read_bio(struct dmz_target *dmz, struct dm_zone *zone,
|
||||
struct bio *bio, sector_t chunk_block,
|
||||
unsigned int nr_blocks)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
sector_t sector;
|
||||
struct bio *clone;
|
||||
|
||||
/* BIO remap sector */
|
||||
sector = dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
|
||||
|
||||
/* If the read is not partial, there is no need to clone the BIO */
|
||||
if (nr_blocks == dmz_bio_blocks(bio)) {
|
||||
/* Setup and submit the BIO */
|
||||
bio->bi_iter.bi_sector = sector;
|
||||
atomic_inc(&bioctx->ref);
|
||||
generic_make_request(bio);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Partial BIO: we need to clone the BIO */
|
||||
clone = bio_clone_fast(bio, GFP_NOIO, dmz->bio_set);
|
||||
if (!clone)
|
||||
return -ENOMEM;
|
||||
|
||||
/* Setup the clone */
|
||||
clone->bi_iter.bi_sector = sector;
|
||||
clone->bi_iter.bi_size = dmz_blk2sect(nr_blocks) << SECTOR_SHIFT;
|
||||
clone->bi_end_io = dmz_read_bio_end_io;
|
||||
clone->bi_private = bioctx;
|
||||
|
||||
bio_advance(bio, clone->bi_iter.bi_size);
|
||||
|
||||
/* Submit the clone */
|
||||
atomic_inc(&bioctx->ref);
|
||||
generic_make_request(clone);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Zero out pages of discarded blocks accessed by a read BIO.
|
||||
*/
|
||||
static void dmz_handle_read_zero(struct dmz_target *dmz, struct bio *bio,
|
||||
sector_t chunk_block, unsigned int nr_blocks)
|
||||
{
|
||||
unsigned int size = nr_blocks << DMZ_BLOCK_SHIFT;
|
||||
|
||||
/* Clear nr_blocks */
|
||||
swap(bio->bi_iter.bi_size, size);
|
||||
zero_fill_bio(bio);
|
||||
swap(bio->bi_iter.bi_size, size);
|
||||
|
||||
bio_advance(bio, size);
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a read BIO.
|
||||
*/
|
||||
static int dmz_handle_read(struct dmz_target *dmz, struct dm_zone *zone,
|
||||
struct bio *bio)
|
||||
{
|
||||
sector_t chunk_block = dmz_chunk_block(dmz->dev, dmz_bio_block(bio));
|
||||
unsigned int nr_blocks = dmz_bio_blocks(bio);
|
||||
sector_t end_block = chunk_block + nr_blocks;
|
||||
struct dm_zone *rzone, *bzone;
|
||||
int ret;
|
||||
|
||||
/* Read into unmapped chunks need only zeroing the BIO buffer */
|
||||
if (!zone) {
|
||||
zero_fill_bio(bio);
|
||||
return 0;
|
||||
}
|
||||
|
||||
dmz_dev_debug(dmz->dev, "READ chunk %llu -> %s zone %u, block %llu, %u blocks",
|
||||
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
|
||||
(dmz_is_rnd(zone) ? "RND" : "SEQ"),
|
||||
dmz_id(dmz->metadata, zone),
|
||||
(unsigned long long)chunk_block, nr_blocks);
|
||||
|
||||
/* Check block validity to determine the read location */
|
||||
bzone = zone->bzone;
|
||||
while (chunk_block < end_block) {
|
||||
nr_blocks = 0;
|
||||
if (dmz_is_rnd(zone) || chunk_block < zone->wp_block) {
|
||||
/* Test block validity in the data zone */
|
||||
ret = dmz_block_valid(dmz->metadata, zone, chunk_block);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
if (ret > 0) {
|
||||
/* Read data zone blocks */
|
||||
nr_blocks = ret;
|
||||
rzone = zone;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* No valid blocks found in the data zone.
|
||||
* Check the buffer zone, if there is one.
|
||||
*/
|
||||
if (!nr_blocks && bzone) {
|
||||
ret = dmz_block_valid(dmz->metadata, bzone, chunk_block);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
if (ret > 0) {
|
||||
/* Read buffer zone blocks */
|
||||
nr_blocks = ret;
|
||||
rzone = bzone;
|
||||
}
|
||||
}
|
||||
|
||||
if (nr_blocks) {
|
||||
/* Valid blocks found: read them */
|
||||
nr_blocks = min_t(unsigned int, nr_blocks, end_block - chunk_block);
|
||||
ret = dmz_submit_read_bio(dmz, rzone, bio, chunk_block, nr_blocks);
|
||||
if (ret)
|
||||
return ret;
|
||||
chunk_block += nr_blocks;
|
||||
} else {
|
||||
/* No valid block: zeroout the current BIO block */
|
||||
dmz_handle_read_zero(dmz, bio, chunk_block, 1);
|
||||
chunk_block++;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Issue a write BIO to a zone.
|
||||
*/
|
||||
static void dmz_submit_write_bio(struct dmz_target *dmz, struct dm_zone *zone,
|
||||
struct bio *bio, sector_t chunk_block,
|
||||
unsigned int nr_blocks)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
|
||||
/* Setup and submit the BIO */
|
||||
bio->bi_bdev = dmz->dev->bdev;
|
||||
bio->bi_iter.bi_sector = dmz_start_sect(dmz->metadata, zone) + dmz_blk2sect(chunk_block);
|
||||
atomic_inc(&bioctx->ref);
|
||||
generic_make_request(bio);
|
||||
|
||||
if (dmz_is_seq(zone))
|
||||
zone->wp_block += nr_blocks;
|
||||
}
|
||||
|
||||
/*
|
||||
* Write blocks directly in a data zone, at the write pointer.
|
||||
* If a buffer zone is assigned, invalidate the blocks written
|
||||
* in place.
|
||||
*/
|
||||
static int dmz_handle_direct_write(struct dmz_target *dmz,
|
||||
struct dm_zone *zone, struct bio *bio,
|
||||
sector_t chunk_block,
|
||||
unsigned int nr_blocks)
|
||||
{
|
||||
struct dmz_metadata *zmd = dmz->metadata;
|
||||
struct dm_zone *bzone = zone->bzone;
|
||||
int ret;
|
||||
|
||||
if (dmz_is_readonly(zone))
|
||||
return -EROFS;
|
||||
|
||||
/* Submit write */
|
||||
dmz_submit_write_bio(dmz, zone, bio, chunk_block, nr_blocks);
|
||||
|
||||
/*
|
||||
* Validate the blocks in the data zone and invalidate
|
||||
* in the buffer zone, if there is one.
|
||||
*/
|
||||
ret = dmz_validate_blocks(zmd, zone, chunk_block, nr_blocks);
|
||||
if (ret == 0 && bzone)
|
||||
ret = dmz_invalidate_blocks(zmd, bzone, chunk_block, nr_blocks);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Write blocks in the buffer zone of @zone.
|
||||
* If no buffer zone is assigned yet, get one.
|
||||
* Called with @zone write locked.
|
||||
*/
|
||||
static int dmz_handle_buffered_write(struct dmz_target *dmz,
|
||||
struct dm_zone *zone, struct bio *bio,
|
||||
sector_t chunk_block,
|
||||
unsigned int nr_blocks)
|
||||
{
|
||||
struct dmz_metadata *zmd = dmz->metadata;
|
||||
struct dm_zone *bzone;
|
||||
int ret;
|
||||
|
||||
/* Get the buffer zone. One will be allocated if needed */
|
||||
bzone = dmz_get_chunk_buffer(zmd, zone);
|
||||
if (!bzone)
|
||||
return -ENOSPC;
|
||||
|
||||
if (dmz_is_readonly(bzone))
|
||||
return -EROFS;
|
||||
|
||||
/* Submit write */
|
||||
dmz_submit_write_bio(dmz, bzone, bio, chunk_block, nr_blocks);
|
||||
|
||||
/*
|
||||
* Validate the blocks in the buffer zone
|
||||
* and invalidate in the data zone.
|
||||
*/
|
||||
ret = dmz_validate_blocks(zmd, bzone, chunk_block, nr_blocks);
|
||||
if (ret == 0 && chunk_block < zone->wp_block)
|
||||
ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a write BIO.
|
||||
*/
|
||||
static int dmz_handle_write(struct dmz_target *dmz, struct dm_zone *zone,
|
||||
struct bio *bio)
|
||||
{
|
||||
sector_t chunk_block = dmz_chunk_block(dmz->dev, dmz_bio_block(bio));
|
||||
unsigned int nr_blocks = dmz_bio_blocks(bio);
|
||||
|
||||
if (!zone)
|
||||
return -ENOSPC;
|
||||
|
||||
dmz_dev_debug(dmz->dev, "WRITE chunk %llu -> %s zone %u, block %llu, %u blocks",
|
||||
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
|
||||
(dmz_is_rnd(zone) ? "RND" : "SEQ"),
|
||||
dmz_id(dmz->metadata, zone),
|
||||
(unsigned long long)chunk_block, nr_blocks);
|
||||
|
||||
if (dmz_is_rnd(zone) || chunk_block == zone->wp_block) {
|
||||
/*
|
||||
* zone is a random zone or it is a sequential zone
|
||||
* and the BIO is aligned to the zone write pointer:
|
||||
* direct write the zone.
|
||||
*/
|
||||
return dmz_handle_direct_write(dmz, zone, bio, chunk_block, nr_blocks);
|
||||
}
|
||||
|
||||
/*
|
||||
* This is an unaligned write in a sequential zone:
|
||||
* use buffered write.
|
||||
*/
|
||||
return dmz_handle_buffered_write(dmz, zone, bio, chunk_block, nr_blocks);
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a discard BIO.
|
||||
*/
|
||||
static int dmz_handle_discard(struct dmz_target *dmz, struct dm_zone *zone,
|
||||
struct bio *bio)
|
||||
{
|
||||
struct dmz_metadata *zmd = dmz->metadata;
|
||||
sector_t block = dmz_bio_block(bio);
|
||||
unsigned int nr_blocks = dmz_bio_blocks(bio);
|
||||
sector_t chunk_block = dmz_chunk_block(dmz->dev, block);
|
||||
int ret = 0;
|
||||
|
||||
/* For unmapped chunks, there is nothing to do */
|
||||
if (!zone)
|
||||
return 0;
|
||||
|
||||
if (dmz_is_readonly(zone))
|
||||
return -EROFS;
|
||||
|
||||
dmz_dev_debug(dmz->dev, "DISCARD chunk %llu -> zone %u, block %llu, %u blocks",
|
||||
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
|
||||
dmz_id(zmd, zone),
|
||||
(unsigned long long)chunk_block, nr_blocks);
|
||||
|
||||
/*
|
||||
* Invalidate blocks in the data zone and its
|
||||
* buffer zone if one is mapped.
|
||||
*/
|
||||
if (dmz_is_rnd(zone) || chunk_block < zone->wp_block)
|
||||
ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
|
||||
if (ret == 0 && zone->bzone)
|
||||
ret = dmz_invalidate_blocks(zmd, zone->bzone,
|
||||
chunk_block, nr_blocks);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a BIO.
|
||||
*/
|
||||
static void dmz_handle_bio(struct dmz_target *dmz, struct dm_chunk_work *cw,
|
||||
struct bio *bio)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
struct dmz_metadata *zmd = dmz->metadata;
|
||||
struct dm_zone *zone;
|
||||
int ret;
|
||||
|
||||
/*
|
||||
* Write may trigger a zone allocation. So make sure the
|
||||
* allocation can succeed.
|
||||
*/
|
||||
if (bio_op(bio) == REQ_OP_WRITE)
|
||||
dmz_schedule_reclaim(dmz->reclaim);
|
||||
|
||||
dmz_lock_metadata(zmd);
|
||||
|
||||
/*
|
||||
* Get the data zone mapping the chunk. There may be no
|
||||
* mapping for read and discard. If a mapping is obtained,
|
||||
+ the zone returned will be set to active state.
|
||||
*/
|
||||
zone = dmz_get_chunk_mapping(zmd, dmz_bio_chunk(dmz->dev, bio),
|
||||
bio_op(bio));
|
||||
if (IS_ERR(zone)) {
|
||||
ret = PTR_ERR(zone);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Process the BIO */
|
||||
if (zone) {
|
||||
dmz_activate_zone(zone);
|
||||
bioctx->zone = zone;
|
||||
}
|
||||
|
||||
switch (bio_op(bio)) {
|
||||
case REQ_OP_READ:
|
||||
ret = dmz_handle_read(dmz, zone, bio);
|
||||
break;
|
||||
case REQ_OP_WRITE:
|
||||
ret = dmz_handle_write(dmz, zone, bio);
|
||||
break;
|
||||
case REQ_OP_DISCARD:
|
||||
case REQ_OP_WRITE_ZEROES:
|
||||
ret = dmz_handle_discard(dmz, zone, bio);
|
||||
break;
|
||||
default:
|
||||
dmz_dev_err(dmz->dev, "Unsupported BIO operation 0x%x",
|
||||
bio_op(bio));
|
||||
ret = -EIO;
|
||||
}
|
||||
|
||||
/*
|
||||
* Release the chunk mapping. This will check that the mapping
|
||||
* is still valid, that is, that the zone used still has valid blocks.
|
||||
*/
|
||||
if (zone)
|
||||
dmz_put_chunk_mapping(zmd, zone);
|
||||
out:
|
||||
dmz_bio_endio(bio, errno_to_blk_status(ret));
|
||||
|
||||
dmz_unlock_metadata(zmd);
|
||||
}
|
||||
|
||||
/*
|
||||
* Increment a chunk reference counter.
|
||||
*/
|
||||
static inline void dmz_get_chunk_work(struct dm_chunk_work *cw)
|
||||
{
|
||||
atomic_inc(&cw->refcount);
|
||||
}
|
||||
|
||||
/*
|
||||
* Decrement a chunk work reference count and
|
||||
* free it if it becomes 0.
|
||||
*/
|
||||
static void dmz_put_chunk_work(struct dm_chunk_work *cw)
|
||||
{
|
||||
if (atomic_dec_and_test(&cw->refcount)) {
|
||||
WARN_ON(!bio_list_empty(&cw->bio_list));
|
||||
radix_tree_delete(&cw->target->chunk_rxtree, cw->chunk);
|
||||
kfree(cw);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Chunk BIO work function.
|
||||
*/
|
||||
static void dmz_chunk_work(struct work_struct *work)
|
||||
{
|
||||
struct dm_chunk_work *cw = container_of(work, struct dm_chunk_work, work);
|
||||
struct dmz_target *dmz = cw->target;
|
||||
struct bio *bio;
|
||||
|
||||
mutex_lock(&dmz->chunk_lock);
|
||||
|
||||
/* Process the chunk BIOs */
|
||||
while ((bio = bio_list_pop(&cw->bio_list))) {
|
||||
mutex_unlock(&dmz->chunk_lock);
|
||||
dmz_handle_bio(dmz, cw, bio);
|
||||
mutex_lock(&dmz->chunk_lock);
|
||||
dmz_put_chunk_work(cw);
|
||||
}
|
||||
|
||||
/* Queueing the work incremented the work refcount */
|
||||
dmz_put_chunk_work(cw);
|
||||
|
||||
mutex_unlock(&dmz->chunk_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Flush work.
|
||||
*/
|
||||
static void dmz_flush_work(struct work_struct *work)
|
||||
{
|
||||
struct dmz_target *dmz = container_of(work, struct dmz_target, flush_work.work);
|
||||
struct bio *bio;
|
||||
int ret;
|
||||
|
||||
/* Flush dirty metadata blocks */
|
||||
ret = dmz_flush_metadata(dmz->metadata);
|
||||
|
||||
/* Process queued flush requests */
|
||||
while (1) {
|
||||
spin_lock(&dmz->flush_lock);
|
||||
bio = bio_list_pop(&dmz->flush_list);
|
||||
spin_unlock(&dmz->flush_lock);
|
||||
|
||||
if (!bio)
|
||||
break;
|
||||
|
||||
dmz_bio_endio(bio, errno_to_blk_status(ret));
|
||||
}
|
||||
|
||||
queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
|
||||
}
|
||||
|
||||
/*
|
||||
* Get a chunk work and start it to process a new BIO.
|
||||
* If the BIO chunk has no work yet, create one.
|
||||
*/
|
||||
static void dmz_queue_chunk_work(struct dmz_target *dmz, struct bio *bio)
|
||||
{
|
||||
unsigned int chunk = dmz_bio_chunk(dmz->dev, bio);
|
||||
struct dm_chunk_work *cw;
|
||||
|
||||
mutex_lock(&dmz->chunk_lock);
|
||||
|
||||
/* Get the BIO chunk work. If one is not active yet, create one */
|
||||
cw = radix_tree_lookup(&dmz->chunk_rxtree, chunk);
|
||||
if (!cw) {
|
||||
int ret;
|
||||
|
||||
/* Create a new chunk work */
|
||||
cw = kmalloc(sizeof(struct dm_chunk_work), GFP_NOFS);
|
||||
if (!cw)
|
||||
goto out;
|
||||
|
||||
INIT_WORK(&cw->work, dmz_chunk_work);
|
||||
atomic_set(&cw->refcount, 0);
|
||||
cw->target = dmz;
|
||||
cw->chunk = chunk;
|
||||
bio_list_init(&cw->bio_list);
|
||||
|
||||
ret = radix_tree_insert(&dmz->chunk_rxtree, chunk, cw);
|
||||
if (unlikely(ret)) {
|
||||
kfree(cw);
|
||||
cw = NULL;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
bio_list_add(&cw->bio_list, bio);
|
||||
dmz_get_chunk_work(cw);
|
||||
|
||||
if (queue_work(dmz->chunk_wq, &cw->work))
|
||||
dmz_get_chunk_work(cw);
|
||||
out:
|
||||
mutex_unlock(&dmz->chunk_lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a new BIO.
|
||||
*/
|
||||
static int dmz_map(struct dm_target *ti, struct bio *bio)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
struct dmz_dev *dev = dmz->dev;
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
sector_t sector = bio->bi_iter.bi_sector;
|
||||
unsigned int nr_sectors = bio_sectors(bio);
|
||||
sector_t chunk_sector;
|
||||
|
||||
dmz_dev_debug(dev, "BIO op %d sector %llu + %u => chunk %llu, block %llu, %u blocks",
|
||||
bio_op(bio), (unsigned long long)sector, nr_sectors,
|
||||
(unsigned long long)dmz_bio_chunk(dmz->dev, bio),
|
||||
(unsigned long long)dmz_chunk_block(dmz->dev, dmz_bio_block(bio)),
|
||||
(unsigned int)dmz_bio_blocks(bio));
|
||||
|
||||
bio->bi_bdev = dev->bdev;
|
||||
|
||||
if (!nr_sectors && (bio_op(bio) != REQ_OP_FLUSH) && (bio_op(bio) != REQ_OP_WRITE))
|
||||
return DM_MAPIO_REMAPPED;
|
||||
|
||||
/* The BIO should be block aligned */
|
||||
if ((nr_sectors & DMZ_BLOCK_SECTORS_MASK) || (sector & DMZ_BLOCK_SECTORS_MASK))
|
||||
return DM_MAPIO_KILL;
|
||||
|
||||
/* Initialize the BIO context */
|
||||
bioctx->target = dmz;
|
||||
bioctx->zone = NULL;
|
||||
bioctx->bio = bio;
|
||||
atomic_set(&bioctx->ref, 1);
|
||||
bioctx->status = BLK_STS_OK;
|
||||
|
||||
/* Set the BIO pending in the flush list */
|
||||
if (bio_op(bio) == REQ_OP_FLUSH || (!nr_sectors && bio_op(bio) == REQ_OP_WRITE)) {
|
||||
spin_lock(&dmz->flush_lock);
|
||||
bio_list_add(&dmz->flush_list, bio);
|
||||
spin_unlock(&dmz->flush_lock);
|
||||
mod_delayed_work(dmz->flush_wq, &dmz->flush_work, 0);
|
||||
return DM_MAPIO_SUBMITTED;
|
||||
}
|
||||
|
||||
/* Split zone BIOs to fit entirely into a zone */
|
||||
chunk_sector = sector & (dev->zone_nr_sectors - 1);
|
||||
if (chunk_sector + nr_sectors > dev->zone_nr_sectors)
|
||||
dm_accept_partial_bio(bio, dev->zone_nr_sectors - chunk_sector);
|
||||
|
||||
/* Now ready to handle this BIO */
|
||||
dmz_reclaim_bio_acc(dmz->reclaim);
|
||||
dmz_queue_chunk_work(dmz, bio);
|
||||
|
||||
return DM_MAPIO_SUBMITTED;
|
||||
}
|
||||
|
||||
/*
|
||||
* Completed target BIO processing.
|
||||
*/
|
||||
static int dmz_end_io(struct dm_target *ti, struct bio *bio, blk_status_t *error)
|
||||
{
|
||||
struct dmz_bioctx *bioctx = dm_per_bio_data(bio, sizeof(struct dmz_bioctx));
|
||||
|
||||
if (bioctx->status == BLK_STS_OK && *error)
|
||||
bioctx->status = *error;
|
||||
|
||||
if (!atomic_dec_and_test(&bioctx->ref))
|
||||
return DM_ENDIO_INCOMPLETE;
|
||||
|
||||
/* Done */
|
||||
bio->bi_status = bioctx->status;
|
||||
|
||||
if (bioctx->zone) {
|
||||
struct dm_zone *zone = bioctx->zone;
|
||||
|
||||
if (*error && bio_op(bio) == REQ_OP_WRITE) {
|
||||
if (dmz_is_seq(zone))
|
||||
set_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
|
||||
}
|
||||
dmz_deactivate_zone(zone);
|
||||
}
|
||||
|
||||
return DM_ENDIO_DONE;
|
||||
}
|
||||
|
||||
/*
|
||||
* Get zoned device information.
|
||||
*/
|
||||
static int dmz_get_zoned_device(struct dm_target *ti, char *path)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
struct request_queue *q;
|
||||
struct dmz_dev *dev;
|
||||
int ret;
|
||||
|
||||
/* Get the target device */
|
||||
ret = dm_get_device(ti, path, dm_table_get_mode(ti->table), &dmz->ddev);
|
||||
if (ret) {
|
||||
ti->error = "Get target device failed";
|
||||
dmz->ddev = NULL;
|
||||
return ret;
|
||||
}
|
||||
|
||||
dev = kzalloc(sizeof(struct dmz_dev), GFP_KERNEL);
|
||||
if (!dev) {
|
||||
ret = -ENOMEM;
|
||||
goto err;
|
||||
}
|
||||
|
||||
dev->bdev = dmz->ddev->bdev;
|
||||
(void)bdevname(dev->bdev, dev->name);
|
||||
|
||||
if (bdev_zoned_model(dev->bdev) == BLK_ZONED_NONE) {
|
||||
ti->error = "Not a zoned block device";
|
||||
ret = -EINVAL;
|
||||
goto err;
|
||||
}
|
||||
|
||||
dev->capacity = i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT;
|
||||
if (ti->begin || (ti->len != dev->capacity)) {
|
||||
ti->error = "Partial mapping not supported";
|
||||
ret = -EINVAL;
|
||||
goto err;
|
||||
}
|
||||
|
||||
q = bdev_get_queue(dev->bdev);
|
||||
dev->zone_nr_sectors = q->limits.chunk_sectors;
|
||||
dev->zone_nr_sectors_shift = ilog2(dev->zone_nr_sectors);
|
||||
|
||||
dev->zone_nr_blocks = dmz_sect2blk(dev->zone_nr_sectors);
|
||||
dev->zone_nr_blocks_shift = ilog2(dev->zone_nr_blocks);
|
||||
|
||||
dev->nr_zones = (dev->capacity + dev->zone_nr_sectors - 1)
|
||||
>> dev->zone_nr_sectors_shift;
|
||||
|
||||
dmz->dev = dev;
|
||||
|
||||
return 0;
|
||||
err:
|
||||
dm_put_device(ti, dmz->ddev);
|
||||
kfree(dev);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Cleanup zoned device information.
|
||||
*/
|
||||
static void dmz_put_zoned_device(struct dm_target *ti)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
dm_put_device(ti, dmz->ddev);
|
||||
kfree(dmz->dev);
|
||||
dmz->dev = NULL;
|
||||
}
|
||||
|
||||
/*
|
||||
* Setup target.
|
||||
*/
|
||||
static int dmz_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
||||
{
|
||||
struct dmz_target *dmz;
|
||||
struct dmz_dev *dev;
|
||||
int ret;
|
||||
|
||||
/* Check arguments */
|
||||
if (argc != 1) {
|
||||
ti->error = "Invalid argument count";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Allocate and initialize the target descriptor */
|
||||
dmz = kzalloc(sizeof(struct dmz_target), GFP_KERNEL);
|
||||
if (!dmz) {
|
||||
ti->error = "Unable to allocate the zoned target descriptor";
|
||||
return -ENOMEM;
|
||||
}
|
||||
ti->private = dmz;
|
||||
|
||||
/* Get the target zoned block device */
|
||||
ret = dmz_get_zoned_device(ti, argv[0]);
|
||||
if (ret) {
|
||||
dmz->ddev = NULL;
|
||||
goto err;
|
||||
}
|
||||
|
||||
/* Initialize metadata */
|
||||
dev = dmz->dev;
|
||||
ret = dmz_ctr_metadata(dev, &dmz->metadata);
|
||||
if (ret) {
|
||||
ti->error = "Metadata initialization failed";
|
||||
goto err_dev;
|
||||
}
|
||||
|
||||
/* Set target (no write same support) */
|
||||
ti->max_io_len = dev->zone_nr_sectors << 9;
|
||||
ti->num_flush_bios = 1;
|
||||
ti->num_discard_bios = 1;
|
||||
ti->num_write_zeroes_bios = 1;
|
||||
ti->per_io_data_size = sizeof(struct dmz_bioctx);
|
||||
ti->flush_supported = true;
|
||||
ti->discards_supported = true;
|
||||
ti->split_discard_bios = true;
|
||||
|
||||
/* The exposed capacity is the number of chunks that can be mapped */
|
||||
ti->len = (sector_t)dmz_nr_chunks(dmz->metadata) << dev->zone_nr_sectors_shift;
|
||||
|
||||
/* Zone BIO */
|
||||
dmz->bio_set = bioset_create(DMZ_MIN_BIOS, 0, 0);
|
||||
if (!dmz->bio_set) {
|
||||
ti->error = "Create BIO set failed";
|
||||
ret = -ENOMEM;
|
||||
goto err_meta;
|
||||
}
|
||||
|
||||
/* Chunk BIO work */
|
||||
mutex_init(&dmz->chunk_lock);
|
||||
INIT_RADIX_TREE(&dmz->chunk_rxtree, GFP_NOFS);
|
||||
dmz->chunk_wq = alloc_workqueue("dmz_cwq_%s", WQ_MEM_RECLAIM | WQ_UNBOUND,
|
||||
0, dev->name);
|
||||
if (!dmz->chunk_wq) {
|
||||
ti->error = "Create chunk workqueue failed";
|
||||
ret = -ENOMEM;
|
||||
goto err_bio;
|
||||
}
|
||||
|
||||
/* Flush work */
|
||||
spin_lock_init(&dmz->flush_lock);
|
||||
bio_list_init(&dmz->flush_list);
|
||||
INIT_DELAYED_WORK(&dmz->flush_work, dmz_flush_work);
|
||||
dmz->flush_wq = alloc_ordered_workqueue("dmz_fwq_%s", WQ_MEM_RECLAIM,
|
||||
dev->name);
|
||||
if (!dmz->flush_wq) {
|
||||
ti->error = "Create flush workqueue failed";
|
||||
ret = -ENOMEM;
|
||||
goto err_cwq;
|
||||
}
|
||||
mod_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
|
||||
|
||||
/* Initialize reclaim */
|
||||
ret = dmz_ctr_reclaim(dev, dmz->metadata, &dmz->reclaim);
|
||||
if (ret) {
|
||||
ti->error = "Zone reclaim initialization failed";
|
||||
goto err_fwq;
|
||||
}
|
||||
|
||||
dmz_dev_info(dev, "Target device: %llu 512-byte logical sectors (%llu blocks)",
|
||||
(unsigned long long)ti->len,
|
||||
(unsigned long long)dmz_sect2blk(ti->len));
|
||||
|
||||
return 0;
|
||||
err_fwq:
|
||||
destroy_workqueue(dmz->flush_wq);
|
||||
err_cwq:
|
||||
destroy_workqueue(dmz->chunk_wq);
|
||||
err_bio:
|
||||
bioset_free(dmz->bio_set);
|
||||
err_meta:
|
||||
dmz_dtr_metadata(dmz->metadata);
|
||||
err_dev:
|
||||
dmz_put_zoned_device(ti);
|
||||
err:
|
||||
kfree(dmz);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Cleanup target.
|
||||
*/
|
||||
static void dmz_dtr(struct dm_target *ti)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
flush_workqueue(dmz->chunk_wq);
|
||||
destroy_workqueue(dmz->chunk_wq);
|
||||
|
||||
dmz_dtr_reclaim(dmz->reclaim);
|
||||
|
||||
cancel_delayed_work_sync(&dmz->flush_work);
|
||||
destroy_workqueue(dmz->flush_wq);
|
||||
|
||||
(void) dmz_flush_metadata(dmz->metadata);
|
||||
|
||||
dmz_dtr_metadata(dmz->metadata);
|
||||
|
||||
bioset_free(dmz->bio_set);
|
||||
|
||||
dmz_put_zoned_device(ti);
|
||||
|
||||
kfree(dmz);
|
||||
}
|
||||
|
||||
/*
|
||||
* Setup target request queue limits.
|
||||
*/
|
||||
static void dmz_io_hints(struct dm_target *ti, struct queue_limits *limits)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
unsigned int chunk_sectors = dmz->dev->zone_nr_sectors;
|
||||
|
||||
limits->logical_block_size = DMZ_BLOCK_SIZE;
|
||||
limits->physical_block_size = DMZ_BLOCK_SIZE;
|
||||
|
||||
blk_limits_io_min(limits, DMZ_BLOCK_SIZE);
|
||||
blk_limits_io_opt(limits, DMZ_BLOCK_SIZE);
|
||||
|
||||
limits->discard_alignment = DMZ_BLOCK_SIZE;
|
||||
limits->discard_granularity = DMZ_BLOCK_SIZE;
|
||||
limits->max_discard_sectors = chunk_sectors;
|
||||
limits->max_hw_discard_sectors = chunk_sectors;
|
||||
limits->max_write_zeroes_sectors = chunk_sectors;
|
||||
|
||||
/* FS hint to try to align to the device zone size */
|
||||
limits->chunk_sectors = chunk_sectors;
|
||||
limits->max_sectors = chunk_sectors;
|
||||
|
||||
/* We are exposing a drive-managed zoned block device */
|
||||
limits->zoned = BLK_ZONED_NONE;
|
||||
}
|
||||
|
||||
/*
|
||||
* Pass on ioctl to the backend device.
|
||||
*/
|
||||
static int dmz_prepare_ioctl(struct dm_target *ti,
|
||||
struct block_device **bdev, fmode_t *mode)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
*bdev = dmz->dev->bdev;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Stop works on suspend.
|
||||
*/
|
||||
static void dmz_suspend(struct dm_target *ti)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
flush_workqueue(dmz->chunk_wq);
|
||||
dmz_suspend_reclaim(dmz->reclaim);
|
||||
cancel_delayed_work_sync(&dmz->flush_work);
|
||||
}
|
||||
|
||||
/*
|
||||
* Restart works on resume or if suspend failed.
|
||||
*/
|
||||
static void dmz_resume(struct dm_target *ti)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
queue_delayed_work(dmz->flush_wq, &dmz->flush_work, DMZ_FLUSH_PERIOD);
|
||||
dmz_resume_reclaim(dmz->reclaim);
|
||||
}
|
||||
|
||||
static int dmz_iterate_devices(struct dm_target *ti,
|
||||
iterate_devices_callout_fn fn, void *data)
|
||||
{
|
||||
struct dmz_target *dmz = ti->private;
|
||||
|
||||
return fn(ti, dmz->ddev, 0, dmz->dev->capacity, data);
|
||||
}
|
||||
|
||||
static struct target_type dmz_type = {
|
||||
.name = "zoned",
|
||||
.version = {1, 0, 0},
|
||||
.features = DM_TARGET_SINGLETON | DM_TARGET_ZONED_HM,
|
||||
.module = THIS_MODULE,
|
||||
.ctr = dmz_ctr,
|
||||
.dtr = dmz_dtr,
|
||||
.map = dmz_map,
|
||||
.end_io = dmz_end_io,
|
||||
.io_hints = dmz_io_hints,
|
||||
.prepare_ioctl = dmz_prepare_ioctl,
|
||||
.postsuspend = dmz_suspend,
|
||||
.resume = dmz_resume,
|
||||
.iterate_devices = dmz_iterate_devices,
|
||||
};
|
||||
|
||||
static int __init dmz_init(void)
|
||||
{
|
||||
return dm_register_target(&dmz_type);
|
||||
}
|
||||
|
||||
static void __exit dmz_exit(void)
|
||||
{
|
||||
dm_unregister_target(&dmz_type);
|
||||
}
|
||||
|
||||
module_init(dmz_init);
|
||||
module_exit(dmz_exit);
|
||||
|
||||
MODULE_DESCRIPTION(DM_NAME " target for zoned block devices");
|
||||
MODULE_AUTHOR("Damien Le Moal <damien.lemoal@wdc.com>");
|
||||
MODULE_LICENSE("GPL");
|
228
drivers/md/dm-zoned.h
Normal file
228
drivers/md/dm-zoned.h
Normal file
|
@ -0,0 +1,228 @@
|
|||
/*
|
||||
* Copyright (C) 2017 Western Digital Corporation or its affiliates.
|
||||
*
|
||||
* This file is released under the GPL.
|
||||
*/
|
||||
|
||||
#ifndef DM_ZONED_H
|
||||
#define DM_ZONED_H
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/blkdev.h>
|
||||
#include <linux/device-mapper.h>
|
||||
#include <linux/dm-kcopyd.h>
|
||||
#include <linux/list.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/workqueue.h>
|
||||
#include <linux/rwsem.h>
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/radix-tree.h>
|
||||
#include <linux/shrinker.h>
|
||||
|
||||
/*
|
||||
* dm-zoned creates block devices with 4KB blocks, always.
|
||||
*/
|
||||
#define DMZ_BLOCK_SHIFT 12
|
||||
#define DMZ_BLOCK_SIZE (1 << DMZ_BLOCK_SHIFT)
|
||||
#define DMZ_BLOCK_MASK (DMZ_BLOCK_SIZE - 1)
|
||||
|
||||
#define DMZ_BLOCK_SHIFT_BITS (DMZ_BLOCK_SHIFT + 3)
|
||||
#define DMZ_BLOCK_SIZE_BITS (1 << DMZ_BLOCK_SHIFT_BITS)
|
||||
#define DMZ_BLOCK_MASK_BITS (DMZ_BLOCK_SIZE_BITS - 1)
|
||||
|
||||
#define DMZ_BLOCK_SECTORS_SHIFT (DMZ_BLOCK_SHIFT - SECTOR_SHIFT)
|
||||
#define DMZ_BLOCK_SECTORS (DMZ_BLOCK_SIZE >> SECTOR_SHIFT)
|
||||
#define DMZ_BLOCK_SECTORS_MASK (DMZ_BLOCK_SECTORS - 1)
|
||||
|
||||
/*
|
||||
* 4KB block <-> 512B sector conversion.
|
||||
*/
|
||||
#define dmz_blk2sect(b) ((sector_t)(b) << DMZ_BLOCK_SECTORS_SHIFT)
|
||||
#define dmz_sect2blk(s) ((sector_t)(s) >> DMZ_BLOCK_SECTORS_SHIFT)
|
||||
|
||||
#define dmz_bio_block(bio) dmz_sect2blk((bio)->bi_iter.bi_sector)
|
||||
#define dmz_bio_blocks(bio) dmz_sect2blk(bio_sectors(bio))
|
||||
|
||||
/*
|
||||
* Zoned block device information.
|
||||
*/
|
||||
struct dmz_dev {
|
||||
struct block_device *bdev;
|
||||
|
||||
char name[BDEVNAME_SIZE];
|
||||
|
||||
sector_t capacity;
|
||||
|
||||
unsigned int nr_zones;
|
||||
|
||||
sector_t zone_nr_sectors;
|
||||
unsigned int zone_nr_sectors_shift;
|
||||
|
||||
sector_t zone_nr_blocks;
|
||||
sector_t zone_nr_blocks_shift;
|
||||
};
|
||||
|
||||
#define dmz_bio_chunk(dev, bio) ((bio)->bi_iter.bi_sector >> \
|
||||
(dev)->zone_nr_sectors_shift)
|
||||
#define dmz_chunk_block(dev, b) ((b) & ((dev)->zone_nr_blocks - 1))
|
||||
|
||||
/*
|
||||
* Zone descriptor.
|
||||
*/
|
||||
struct dm_zone {
|
||||
/* For listing the zone depending on its state */
|
||||
struct list_head link;
|
||||
|
||||
/* Zone type and state */
|
||||
unsigned long flags;
|
||||
|
||||
/* Zone activation reference count */
|
||||
atomic_t refcount;
|
||||
|
||||
/* Zone write pointer block (relative to the zone start block) */
|
||||
unsigned int wp_block;
|
||||
|
||||
/* Zone weight (number of valid blocks in the zone) */
|
||||
unsigned int weight;
|
||||
|
||||
/* The chunk that the zone maps */
|
||||
unsigned int chunk;
|
||||
|
||||
/*
|
||||
* For a sequential data zone, pointer to the random zone
|
||||
* used as a buffer for processing unaligned writes.
|
||||
* For a buffer zone, this points back to the data zone.
|
||||
*/
|
||||
struct dm_zone *bzone;
|
||||
};
|
||||
|
||||
/*
|
||||
* Zone flags.
|
||||
*/
|
||||
enum {
|
||||
/* Zone write type */
|
||||
DMZ_RND,
|
||||
DMZ_SEQ,
|
||||
|
||||
/* Zone critical condition */
|
||||
DMZ_OFFLINE,
|
||||
DMZ_READ_ONLY,
|
||||
|
||||
/* How the zone is being used */
|
||||
DMZ_META,
|
||||
DMZ_DATA,
|
||||
DMZ_BUF,
|
||||
|
||||
/* Zone internal state */
|
||||
DMZ_ACTIVE,
|
||||
DMZ_RECLAIM,
|
||||
DMZ_SEQ_WRITE_ERR,
|
||||
};
|
||||
|
||||
/*
|
||||
* Zone data accessors.
|
||||
*/
|
||||
#define dmz_is_rnd(z) test_bit(DMZ_RND, &(z)->flags)
|
||||
#define dmz_is_seq(z) test_bit(DMZ_SEQ, &(z)->flags)
|
||||
#define dmz_is_empty(z) ((z)->wp_block == 0)
|
||||
#define dmz_is_offline(z) test_bit(DMZ_OFFLINE, &(z)->flags)
|
||||
#define dmz_is_readonly(z) test_bit(DMZ_READ_ONLY, &(z)->flags)
|
||||
#define dmz_is_active(z) test_bit(DMZ_ACTIVE, &(z)->flags)
|
||||
#define dmz_in_reclaim(z) test_bit(DMZ_RECLAIM, &(z)->flags)
|
||||
#define dmz_seq_write_err(z) test_bit(DMZ_SEQ_WRITE_ERR, &(z)->flags)
|
||||
|
||||
#define dmz_is_meta(z) test_bit(DMZ_META, &(z)->flags)
|
||||
#define dmz_is_buf(z) test_bit(DMZ_BUF, &(z)->flags)
|
||||
#define dmz_is_data(z) test_bit(DMZ_DATA, &(z)->flags)
|
||||
|
||||
#define dmz_weight(z) ((z)->weight)
|
||||
|
||||
/*
|
||||
* Message functions.
|
||||
*/
|
||||
#define dmz_dev_info(dev, format, args...) \
|
||||
DMINFO("(%s): " format, (dev)->name, ## args)
|
||||
|
||||
#define dmz_dev_err(dev, format, args...) \
|
||||
DMERR("(%s): " format, (dev)->name, ## args)
|
||||
|
||||
#define dmz_dev_warn(dev, format, args...) \
|
||||
DMWARN("(%s): " format, (dev)->name, ## args)
|
||||
|
||||
#define dmz_dev_debug(dev, format, args...) \
|
||||
DMDEBUG("(%s): " format, (dev)->name, ## args)
|
||||
|
||||
struct dmz_metadata;
|
||||
struct dmz_reclaim;
|
||||
|
||||
/*
|
||||
* Functions defined in dm-zoned-metadata.c
|
||||
*/
|
||||
int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **zmd);
|
||||
void dmz_dtr_metadata(struct dmz_metadata *zmd);
|
||||
int dmz_resume_metadata(struct dmz_metadata *zmd);
|
||||
|
||||
void dmz_lock_map(struct dmz_metadata *zmd);
|
||||
void dmz_unlock_map(struct dmz_metadata *zmd);
|
||||
void dmz_lock_metadata(struct dmz_metadata *zmd);
|
||||
void dmz_unlock_metadata(struct dmz_metadata *zmd);
|
||||
void dmz_lock_flush(struct dmz_metadata *zmd);
|
||||
void dmz_unlock_flush(struct dmz_metadata *zmd);
|
||||
int dmz_flush_metadata(struct dmz_metadata *zmd);
|
||||
|
||||
unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
unsigned int dmz_nr_chunks(struct dmz_metadata *zmd);
|
||||
|
||||
#define DMZ_ALLOC_RND 0x01
|
||||
#define DMZ_ALLOC_RECLAIM 0x02
|
||||
|
||||
struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags);
|
||||
void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
|
||||
void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
|
||||
unsigned int chunk);
|
||||
void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd);
|
||||
unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd);
|
||||
|
||||
void dmz_activate_zone(struct dm_zone *zone);
|
||||
void dmz_deactivate_zone(struct dm_zone *zone);
|
||||
|
||||
int dmz_lock_zone_reclaim(struct dm_zone *zone);
|
||||
void dmz_unlock_zone_reclaim(struct dm_zone *zone);
|
||||
struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd);
|
||||
|
||||
struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd,
|
||||
unsigned int chunk, int op);
|
||||
void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *zone);
|
||||
struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
|
||||
struct dm_zone *dzone);
|
||||
|
||||
int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
|
||||
sector_t chunk_block, unsigned int nr_blocks);
|
||||
int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
|
||||
sector_t chunk_block, unsigned int nr_blocks);
|
||||
int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
|
||||
sector_t chunk_block);
|
||||
int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
|
||||
sector_t *chunk_block);
|
||||
int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
|
||||
struct dm_zone *to_zone);
|
||||
int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
|
||||
struct dm_zone *to_zone, sector_t chunk_block);
|
||||
|
||||
/*
|
||||
* Functions defined in dm-zoned-reclaim.c
|
||||
*/
|
||||
int dmz_ctr_reclaim(struct dmz_dev *dev, struct dmz_metadata *zmd,
|
||||
struct dmz_reclaim **zrc);
|
||||
void dmz_dtr_reclaim(struct dmz_reclaim *zrc);
|
||||
void dmz_suspend_reclaim(struct dmz_reclaim *zrc);
|
||||
void dmz_resume_reclaim(struct dmz_reclaim *zrc);
|
||||
void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc);
|
||||
void dmz_schedule_reclaim(struct dmz_reclaim *zrc);
|
||||
|
||||
#endif /* DM_ZONED_H */
|
Loading…
Reference in a new issue