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![Christoph Hellwig](/assets/img/avatar_default.png)
Just use the %pg format specifier to print the block device name directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
3047 lines
72 KiB
C
3047 lines
72 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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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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#include <linux/crc32.h>
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#include <linux/sched/mm.h>
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#define DM_MSG_PREFIX "zoned metadata"
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/*
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* Metadata version.
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*/
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#define DMZ_META_VER 2
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/*
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* On-disk super block magic.
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*/
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#define DMZ_MAGIC ((((unsigned int)('D')) << 24) | \
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(((unsigned int)('Z')) << 16) | \
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(((unsigned int)('B')) << 8) | \
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((unsigned int)('D')))
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/*
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* On disk super block.
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* This uses only 512 B but uses on disk a full 4KB block. This block is
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* followed on disk by the mapping table of chunks to zones and the bitmap
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* blocks indicating zone block validity.
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* The overall resulting metadata format is:
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* (1) Super block (1 block)
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* (2) Chunk mapping table (nr_map_blocks)
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* (3) Bitmap blocks (nr_bitmap_blocks)
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* All metadata blocks are stored in conventional zones, starting from
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* the first conventional zone found on disk.
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*/
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struct dmz_super {
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/* Magic number */
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__le32 magic; /* 4 */
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/* Metadata version number */
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__le32 version; /* 8 */
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/* Generation number */
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__le64 gen; /* 16 */
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/* This block number */
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__le64 sb_block; /* 24 */
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/* The number of metadata blocks, including this super block */
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__le32 nr_meta_blocks; /* 28 */
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/* The number of sequential zones reserved for reclaim */
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__le32 nr_reserved_seq; /* 32 */
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/* The number of entries in the mapping table */
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__le32 nr_chunks; /* 36 */
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/* The number of blocks used for the chunk mapping table */
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__le32 nr_map_blocks; /* 40 */
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/* The number of blocks used for the block bitmaps */
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__le32 nr_bitmap_blocks; /* 44 */
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/* Checksum */
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__le32 crc; /* 48 */
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/* DM-Zoned label */
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u8 dmz_label[32]; /* 80 */
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/* DM-Zoned UUID */
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u8 dmz_uuid[16]; /* 96 */
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/* Device UUID */
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u8 dev_uuid[16]; /* 112 */
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/* Padding to full 512B sector */
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u8 reserved[400]; /* 512 */
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};
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/*
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* Chunk mapping entry: entries are indexed by chunk number
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* and give the zone ID (dzone_id) mapping the chunk on disk.
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* This zone may be sequential or random. If it is a sequential
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* zone, a second zone (bzone_id) used as a write buffer may
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* also be specified. This second zone will always be a randomly
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* writeable zone.
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*/
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struct dmz_map {
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__le32 dzone_id;
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__le32 bzone_id;
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};
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/*
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* Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
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*/
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#define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
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#define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES))
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#define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1)
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#define DMZ_MAP_UNMAPPED UINT_MAX
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/*
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* Meta data block descriptor (for cached metadata blocks).
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*/
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struct dmz_mblock {
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struct rb_node node;
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struct list_head link;
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sector_t no;
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unsigned int ref;
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unsigned long state;
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struct page *page;
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void *data;
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};
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/*
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* Metadata block state flags.
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*/
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enum {
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DMZ_META_DIRTY,
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DMZ_META_READING,
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DMZ_META_WRITING,
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DMZ_META_ERROR,
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};
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/*
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* Super block information (one per metadata set).
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*/
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struct dmz_sb {
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sector_t block;
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struct dmz_dev *dev;
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struct dmz_mblock *mblk;
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struct dmz_super *sb;
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struct dm_zone *zone;
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};
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/*
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* In-memory metadata.
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*/
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struct dmz_metadata {
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struct dmz_dev *dev;
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unsigned int nr_devs;
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char devname[BDEVNAME_SIZE];
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char label[BDEVNAME_SIZE];
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uuid_t uuid;
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sector_t zone_bitmap_size;
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unsigned int zone_nr_bitmap_blocks;
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unsigned int zone_bits_per_mblk;
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sector_t zone_nr_blocks;
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sector_t zone_nr_blocks_shift;
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sector_t zone_nr_sectors;
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sector_t zone_nr_sectors_shift;
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unsigned int nr_bitmap_blocks;
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unsigned int nr_map_blocks;
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unsigned int nr_zones;
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unsigned int nr_useable_zones;
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unsigned int nr_meta_blocks;
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unsigned int nr_meta_zones;
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unsigned int nr_data_zones;
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unsigned int nr_cache_zones;
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unsigned int nr_rnd_zones;
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unsigned int nr_reserved_seq;
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unsigned int nr_chunks;
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/* Zone information array */
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struct xarray zones;
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struct dmz_sb sb[2];
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unsigned int mblk_primary;
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unsigned int sb_version;
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u64 sb_gen;
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unsigned int min_nr_mblks;
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unsigned int max_nr_mblks;
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atomic_t nr_mblks;
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struct rw_semaphore mblk_sem;
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struct mutex mblk_flush_lock;
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spinlock_t mblk_lock;
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struct rb_root mblk_rbtree;
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struct list_head mblk_lru_list;
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struct list_head mblk_dirty_list;
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struct shrinker mblk_shrinker;
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/* Zone allocation management */
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struct mutex map_lock;
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struct dmz_mblock **map_mblk;
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unsigned int nr_cache;
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atomic_t unmap_nr_cache;
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struct list_head unmap_cache_list;
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struct list_head map_cache_list;
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atomic_t nr_reserved_seq_zones;
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struct list_head reserved_seq_zones_list;
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wait_queue_head_t free_wq;
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};
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#define dmz_zmd_info(zmd, format, args...) \
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DMINFO("(%s): " format, (zmd)->label, ## args)
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#define dmz_zmd_err(zmd, format, args...) \
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DMERR("(%s): " format, (zmd)->label, ## args)
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#define dmz_zmd_warn(zmd, format, args...) \
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DMWARN("(%s): " format, (zmd)->label, ## args)
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#define dmz_zmd_debug(zmd, format, args...) \
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DMDEBUG("(%s): " format, (zmd)->label, ## args)
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/*
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* Various accessors
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*/
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static unsigned int dmz_dev_zone_id(struct dmz_metadata *zmd, struct dm_zone *zone)
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{
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if (WARN_ON(!zone))
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return 0;
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return zone->id - zone->dev->zone_offset;
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}
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sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
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{
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unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
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return (sector_t)zone_id << zmd->zone_nr_sectors_shift;
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}
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sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
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{
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unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
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return (sector_t)zone_id << zmd->zone_nr_blocks_shift;
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}
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unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd)
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{
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return zmd->zone_nr_blocks;
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}
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unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd)
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{
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return zmd->zone_nr_blocks_shift;
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}
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unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd)
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{
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return zmd->zone_nr_sectors;
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}
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unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd)
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{
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return zmd->zone_nr_sectors_shift;
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}
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unsigned int dmz_nr_zones(struct dmz_metadata *zmd)
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{
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return zmd->nr_zones;
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}
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unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
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{
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return zmd->nr_chunks;
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}
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unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx)
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{
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return zmd->dev[idx].nr_rnd;
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}
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unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx)
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{
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return atomic_read(&zmd->dev[idx].unmap_nr_rnd);
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}
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unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd)
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{
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return zmd->nr_cache;
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}
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unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd)
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{
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return atomic_read(&zmd->unmap_nr_cache);
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}
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unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx)
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{
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return zmd->dev[idx].nr_seq;
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}
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unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx)
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{
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return atomic_read(&zmd->dev[idx].unmap_nr_seq);
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}
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static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
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{
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return xa_load(&zmd->zones, zone_id);
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}
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static struct dm_zone *dmz_insert(struct dmz_metadata *zmd,
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unsigned int zone_id, struct dmz_dev *dev)
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{
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struct dm_zone *zone = kzalloc(sizeof(struct dm_zone), GFP_KERNEL);
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if (!zone)
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return ERR_PTR(-ENOMEM);
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if (xa_insert(&zmd->zones, zone_id, zone, GFP_KERNEL)) {
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kfree(zone);
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return ERR_PTR(-EBUSY);
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}
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INIT_LIST_HEAD(&zone->link);
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atomic_set(&zone->refcount, 0);
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zone->id = zone_id;
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zone->chunk = DMZ_MAP_UNMAPPED;
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zone->dev = dev;
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return zone;
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}
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const char *dmz_metadata_label(struct dmz_metadata *zmd)
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{
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return (const char *)zmd->label;
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}
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bool dmz_check_dev(struct dmz_metadata *zmd)
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{
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unsigned int i;
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for (i = 0; i < zmd->nr_devs; i++) {
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if (!dmz_check_bdev(&zmd->dev[i]))
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return false;
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}
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return true;
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}
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bool dmz_dev_is_dying(struct dmz_metadata *zmd)
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{
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unsigned int i;
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for (i = 0; i < zmd->nr_devs; i++) {
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if (dmz_bdev_is_dying(&zmd->dev[i]))
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return true;
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}
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return false;
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}
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/*
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* Lock/unlock mapping table.
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* The map lock also protects all the zone lists.
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*/
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void dmz_lock_map(struct dmz_metadata *zmd)
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{
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mutex_lock(&zmd->map_lock);
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}
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void dmz_unlock_map(struct dmz_metadata *zmd)
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{
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mutex_unlock(&zmd->map_lock);
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}
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/*
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* Lock/unlock metadata access. This is a "read" lock on a semaphore
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* that prevents metadata flush from running while metadata are being
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* modified. The actual metadata write mutual exclusion is achieved with
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* the map lock and zone state management (active and reclaim state are
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* mutually exclusive).
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*/
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void dmz_lock_metadata(struct dmz_metadata *zmd)
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{
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down_read(&zmd->mblk_sem);
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}
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void dmz_unlock_metadata(struct dmz_metadata *zmd)
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{
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up_read(&zmd->mblk_sem);
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}
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/*
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* Lock/unlock flush: prevent concurrent executions
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* of dmz_flush_metadata as well as metadata modification in reclaim
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* while flush is being executed.
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*/
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void dmz_lock_flush(struct dmz_metadata *zmd)
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{
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mutex_lock(&zmd->mblk_flush_lock);
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}
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void dmz_unlock_flush(struct dmz_metadata *zmd)
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{
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mutex_unlock(&zmd->mblk_flush_lock);
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}
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/*
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* Allocate a metadata block.
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*/
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static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
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sector_t mblk_no)
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{
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struct dmz_mblock *mblk = NULL;
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/* See if we can reuse cached blocks */
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if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
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spin_lock(&zmd->mblk_lock);
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mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
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struct dmz_mblock, link);
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if (mblk) {
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list_del_init(&mblk->link);
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rb_erase(&mblk->node, &zmd->mblk_rbtree);
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mblk->no = mblk_no;
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}
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spin_unlock(&zmd->mblk_lock);
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if (mblk)
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return mblk;
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}
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/* Allocate a new block */
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mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
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if (!mblk)
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return NULL;
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mblk->page = alloc_page(GFP_NOIO);
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if (!mblk->page) {
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kfree(mblk);
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return NULL;
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}
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RB_CLEAR_NODE(&mblk->node);
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INIT_LIST_HEAD(&mblk->link);
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mblk->ref = 0;
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mblk->state = 0;
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mblk->no = mblk_no;
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mblk->data = page_address(mblk->page);
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atomic_inc(&zmd->nr_mblks);
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return mblk;
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}
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/*
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* Free a metadata block.
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*/
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static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
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{
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__free_pages(mblk->page, 0);
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kfree(mblk);
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atomic_dec(&zmd->nr_mblks);
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}
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/*
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* Insert a metadata block in the rbtree.
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*/
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static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
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{
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struct rb_root *root = &zmd->mblk_rbtree;
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struct rb_node **new = &(root->rb_node), *parent = NULL;
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struct dmz_mblock *b;
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/* Figure out where to put the new node */
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while (*new) {
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b = container_of(*new, struct dmz_mblock, node);
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parent = *new;
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new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
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}
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/* Add new node and rebalance tree */
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rb_link_node(&mblk->node, parent, new);
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rb_insert_color(&mblk->node, root);
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}
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/*
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* Lookup a metadata block in the rbtree. If the block is found, increment
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* its reference count.
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*/
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static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd,
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sector_t mblk_no)
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{
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struct rb_root *root = &zmd->mblk_rbtree;
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struct rb_node *node = root->rb_node;
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struct dmz_mblock *mblk;
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while (node) {
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mblk = container_of(node, struct dmz_mblock, node);
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if (mblk->no == mblk_no) {
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/*
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* If this is the first reference to the block,
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* remove it from the LRU list.
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*/
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mblk->ref++;
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if (mblk->ref == 1 &&
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!test_bit(DMZ_META_DIRTY, &mblk->state))
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list_del_init(&mblk->link);
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return mblk;
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}
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node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
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}
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return NULL;
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}
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/*
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* Metadata block BIO end callback.
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*/
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static void dmz_mblock_bio_end_io(struct bio *bio)
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{
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struct dmz_mblock *mblk = bio->bi_private;
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int flag;
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if (bio->bi_status)
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set_bit(DMZ_META_ERROR, &mblk->state);
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if (bio_op(bio) == REQ_OP_WRITE)
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flag = DMZ_META_WRITING;
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else
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flag = DMZ_META_READING;
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clear_bit_unlock(flag, &mblk->state);
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smp_mb__after_atomic();
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wake_up_bit(&mblk->state, flag);
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bio_put(bio);
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}
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/*
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|
* Read an uncached metadata block from disk and add it to the cache.
|
|
*/
|
|
static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
|
|
sector_t mblk_no)
|
|
{
|
|
struct dmz_mblock *mblk, *m;
|
|
sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
|
|
struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
|
|
struct bio *bio;
|
|
|
|
if (dmz_bdev_is_dying(dev))
|
|
return ERR_PTR(-EIO);
|
|
|
|
/* Get a new block and a BIO to read it */
|
|
mblk = dmz_alloc_mblock(zmd, mblk_no);
|
|
if (!mblk)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
bio = bio_alloc(dev->bdev, 1, REQ_OP_READ | REQ_META | REQ_PRIO,
|
|
GFP_NOIO);
|
|
|
|
spin_lock(&zmd->mblk_lock);
|
|
|
|
/*
|
|
* Make sure that another context did not start reading
|
|
* the block already.
|
|
*/
|
|
m = dmz_get_mblock_fast(zmd, mblk_no);
|
|
if (m) {
|
|
spin_unlock(&zmd->mblk_lock);
|
|
dmz_free_mblock(zmd, mblk);
|
|
bio_put(bio);
|
|
return m;
|
|
}
|
|
|
|
mblk->ref++;
|
|
set_bit(DMZ_META_READING, &mblk->state);
|
|
dmz_insert_mblock(zmd, mblk);
|
|
|
|
spin_unlock(&zmd->mblk_lock);
|
|
|
|
/* Submit read BIO */
|
|
bio->bi_iter.bi_sector = dmz_blk2sect(block);
|
|
bio->bi_private = mblk;
|
|
bio->bi_end_io = dmz_mblock_bio_end_io;
|
|
bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
|
|
submit_bio(bio);
|
|
|
|
return mblk;
|
|
}
|
|
|
|
/*
|
|
* Free metadata blocks.
|
|
*/
|
|
static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd,
|
|
unsigned long limit)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
unsigned long count = 0;
|
|
|
|
if (!zmd->max_nr_mblks)
|
|
return 0;
|
|
|
|
while (!list_empty(&zmd->mblk_lru_list) &&
|
|
atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks &&
|
|
count < limit) {
|
|
mblk = list_first_entry(&zmd->mblk_lru_list,
|
|
struct dmz_mblock, link);
|
|
list_del_init(&mblk->link);
|
|
rb_erase(&mblk->node, &zmd->mblk_rbtree);
|
|
dmz_free_mblock(zmd, mblk);
|
|
count++;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* For mblock shrinker: get the number of unused metadata blocks in the cache.
|
|
*/
|
|
static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
|
|
|
|
return atomic_read(&zmd->nr_mblks);
|
|
}
|
|
|
|
/*
|
|
* For mblock shrinker: scan unused metadata blocks and shrink the cache.
|
|
*/
|
|
static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
|
|
unsigned long count;
|
|
|
|
spin_lock(&zmd->mblk_lock);
|
|
count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
|
|
return count ? count : SHRINK_STOP;
|
|
}
|
|
|
|
/*
|
|
* Release a metadata block.
|
|
*/
|
|
static void dmz_release_mblock(struct dmz_metadata *zmd,
|
|
struct dmz_mblock *mblk)
|
|
{
|
|
|
|
if (!mblk)
|
|
return;
|
|
|
|
spin_lock(&zmd->mblk_lock);
|
|
|
|
mblk->ref--;
|
|
if (mblk->ref == 0) {
|
|
if (test_bit(DMZ_META_ERROR, &mblk->state)) {
|
|
rb_erase(&mblk->node, &zmd->mblk_rbtree);
|
|
dmz_free_mblock(zmd, mblk);
|
|
} else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) {
|
|
list_add_tail(&mblk->link, &zmd->mblk_lru_list);
|
|
dmz_shrink_mblock_cache(zmd, 1);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&zmd->mblk_lock);
|
|
}
|
|
|
|
/*
|
|
* Get a metadata block from the rbtree. If the block
|
|
* is not present, read it from disk.
|
|
*/
|
|
static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
|
|
sector_t mblk_no)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
|
|
|
|
/* Check rbtree */
|
|
spin_lock(&zmd->mblk_lock);
|
|
mblk = dmz_get_mblock_fast(zmd, mblk_no);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
|
|
if (!mblk) {
|
|
/* Cache miss: read the block from disk */
|
|
mblk = dmz_get_mblock_slow(zmd, mblk_no);
|
|
if (IS_ERR(mblk))
|
|
return mblk;
|
|
}
|
|
|
|
/* Wait for on-going read I/O and check for error */
|
|
wait_on_bit_io(&mblk->state, DMZ_META_READING,
|
|
TASK_UNINTERRUPTIBLE);
|
|
if (test_bit(DMZ_META_ERROR, &mblk->state)) {
|
|
dmz_release_mblock(zmd, mblk);
|
|
dmz_check_bdev(dev);
|
|
return ERR_PTR(-EIO);
|
|
}
|
|
|
|
return mblk;
|
|
}
|
|
|
|
/*
|
|
* Mark a metadata block dirty.
|
|
*/
|
|
static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
|
|
{
|
|
spin_lock(&zmd->mblk_lock);
|
|
if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state))
|
|
list_add_tail(&mblk->link, &zmd->mblk_dirty_list);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
}
|
|
|
|
/*
|
|
* Issue a metadata block write BIO.
|
|
*/
|
|
static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
|
|
unsigned int set)
|
|
{
|
|
struct dmz_dev *dev = zmd->sb[set].dev;
|
|
sector_t block = zmd->sb[set].block + mblk->no;
|
|
struct bio *bio;
|
|
|
|
if (dmz_bdev_is_dying(dev))
|
|
return -EIO;
|
|
|
|
bio = bio_alloc(dev->bdev, 1, REQ_OP_WRITE | REQ_META | REQ_PRIO,
|
|
GFP_NOIO);
|
|
|
|
set_bit(DMZ_META_WRITING, &mblk->state);
|
|
|
|
bio->bi_iter.bi_sector = dmz_blk2sect(block);
|
|
bio->bi_private = mblk;
|
|
bio->bi_end_io = dmz_mblock_bio_end_io;
|
|
bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
|
|
submit_bio(bio);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read/write a metadata block.
|
|
*/
|
|
static int dmz_rdwr_block(struct dmz_dev *dev, int op,
|
|
sector_t block, struct page *page)
|
|
{
|
|
struct bio *bio;
|
|
int ret;
|
|
|
|
if (WARN_ON(!dev))
|
|
return -EIO;
|
|
|
|
if (dmz_bdev_is_dying(dev))
|
|
return -EIO;
|
|
|
|
bio = bio_alloc(dev->bdev, 1, op | REQ_SYNC | REQ_META | REQ_PRIO,
|
|
GFP_NOIO);
|
|
bio->bi_iter.bi_sector = dmz_blk2sect(block);
|
|
bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
|
|
ret = submit_bio_wait(bio);
|
|
bio_put(bio);
|
|
|
|
if (ret)
|
|
dmz_check_bdev(dev);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Write super block of the specified metadata set.
|
|
*/
|
|
static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
|
|
{
|
|
struct dmz_mblock *mblk = zmd->sb[set].mblk;
|
|
struct dmz_super *sb = zmd->sb[set].sb;
|
|
struct dmz_dev *dev = zmd->sb[set].dev;
|
|
sector_t sb_block;
|
|
u64 sb_gen = zmd->sb_gen + 1;
|
|
int ret;
|
|
|
|
sb->magic = cpu_to_le32(DMZ_MAGIC);
|
|
|
|
sb->version = cpu_to_le32(zmd->sb_version);
|
|
if (zmd->sb_version > 1) {
|
|
BUILD_BUG_ON(UUID_SIZE != 16);
|
|
export_uuid(sb->dmz_uuid, &zmd->uuid);
|
|
memcpy(sb->dmz_label, zmd->label, BDEVNAME_SIZE);
|
|
export_uuid(sb->dev_uuid, &dev->uuid);
|
|
}
|
|
|
|
sb->gen = cpu_to_le64(sb_gen);
|
|
|
|
/*
|
|
* The metadata always references the absolute block address,
|
|
* ie relative to the entire block range, not the per-device
|
|
* block address.
|
|
*/
|
|
sb_block = zmd->sb[set].zone->id << zmd->zone_nr_blocks_shift;
|
|
sb->sb_block = cpu_to_le64(sb_block);
|
|
sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks);
|
|
sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq);
|
|
sb->nr_chunks = cpu_to_le32(zmd->nr_chunks);
|
|
|
|
sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks);
|
|
sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks);
|
|
|
|
sb->crc = 0;
|
|
sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
|
|
|
|
ret = dmz_rdwr_block(dev, REQ_OP_WRITE, zmd->sb[set].block,
|
|
mblk->page);
|
|
if (ret == 0)
|
|
ret = blkdev_issue_flush(dev->bdev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Write dirty metadata blocks to the specified set.
|
|
*/
|
|
static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
|
|
struct list_head *write_list,
|
|
unsigned int set)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
struct dmz_dev *dev = zmd->sb[set].dev;
|
|
struct blk_plug plug;
|
|
int ret = 0, nr_mblks_submitted = 0;
|
|
|
|
/* Issue writes */
|
|
blk_start_plug(&plug);
|
|
list_for_each_entry(mblk, write_list, link) {
|
|
ret = dmz_write_mblock(zmd, mblk, set);
|
|
if (ret)
|
|
break;
|
|
nr_mblks_submitted++;
|
|
}
|
|
blk_finish_plug(&plug);
|
|
|
|
/* Wait for completion */
|
|
list_for_each_entry(mblk, write_list, link) {
|
|
if (!nr_mblks_submitted)
|
|
break;
|
|
wait_on_bit_io(&mblk->state, DMZ_META_WRITING,
|
|
TASK_UNINTERRUPTIBLE);
|
|
if (test_bit(DMZ_META_ERROR, &mblk->state)) {
|
|
clear_bit(DMZ_META_ERROR, &mblk->state);
|
|
dmz_check_bdev(dev);
|
|
ret = -EIO;
|
|
}
|
|
nr_mblks_submitted--;
|
|
}
|
|
|
|
/* Flush drive cache (this will also sync data) */
|
|
if (ret == 0)
|
|
ret = blkdev_issue_flush(dev->bdev);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Log dirty metadata blocks.
|
|
*/
|
|
static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd,
|
|
struct list_head *write_list)
|
|
{
|
|
unsigned int log_set = zmd->mblk_primary ^ 0x1;
|
|
int ret;
|
|
|
|
/* Write dirty blocks to the log */
|
|
ret = dmz_write_dirty_mblocks(zmd, write_list, log_set);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* No error so far: now validate the log by updating the
|
|
* log index super block generation.
|
|
*/
|
|
ret = dmz_write_sb(zmd, log_set);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Flush dirty metadata blocks.
|
|
*/
|
|
int dmz_flush_metadata(struct dmz_metadata *zmd)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
struct list_head write_list;
|
|
struct dmz_dev *dev;
|
|
int ret;
|
|
|
|
if (WARN_ON(!zmd))
|
|
return 0;
|
|
|
|
INIT_LIST_HEAD(&write_list);
|
|
|
|
/*
|
|
* Make sure that metadata blocks are stable before logging: take
|
|
* the write lock on the metadata semaphore to prevent target BIOs
|
|
* from modifying metadata.
|
|
*/
|
|
down_write(&zmd->mblk_sem);
|
|
dev = zmd->sb[zmd->mblk_primary].dev;
|
|
|
|
/*
|
|
* This is called from the target flush work and reclaim work.
|
|
* Concurrent execution is not allowed.
|
|
*/
|
|
dmz_lock_flush(zmd);
|
|
|
|
if (dmz_bdev_is_dying(dev)) {
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/* Get dirty blocks */
|
|
spin_lock(&zmd->mblk_lock);
|
|
list_splice_init(&zmd->mblk_dirty_list, &write_list);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
|
|
/* If there are no dirty metadata blocks, just flush the device cache */
|
|
if (list_empty(&write_list)) {
|
|
ret = blkdev_issue_flush(dev->bdev);
|
|
goto err;
|
|
}
|
|
|
|
/*
|
|
* The primary metadata set is still clean. Keep it this way until
|
|
* all updates are successful in the secondary set. That is, use
|
|
* the secondary set as a log.
|
|
*/
|
|
ret = dmz_log_dirty_mblocks(zmd, &write_list);
|
|
if (ret)
|
|
goto err;
|
|
|
|
/*
|
|
* The log is on disk. It is now safe to update in place
|
|
* in the primary metadata set.
|
|
*/
|
|
ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary);
|
|
if (ret)
|
|
goto err;
|
|
|
|
ret = dmz_write_sb(zmd, zmd->mblk_primary);
|
|
if (ret)
|
|
goto err;
|
|
|
|
while (!list_empty(&write_list)) {
|
|
mblk = list_first_entry(&write_list, struct dmz_mblock, link);
|
|
list_del_init(&mblk->link);
|
|
|
|
spin_lock(&zmd->mblk_lock);
|
|
clear_bit(DMZ_META_DIRTY, &mblk->state);
|
|
if (mblk->ref == 0)
|
|
list_add_tail(&mblk->link, &zmd->mblk_lru_list);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
}
|
|
|
|
zmd->sb_gen++;
|
|
out:
|
|
dmz_unlock_flush(zmd);
|
|
up_write(&zmd->mblk_sem);
|
|
|
|
return ret;
|
|
|
|
err:
|
|
if (!list_empty(&write_list)) {
|
|
spin_lock(&zmd->mblk_lock);
|
|
list_splice(&write_list, &zmd->mblk_dirty_list);
|
|
spin_unlock(&zmd->mblk_lock);
|
|
}
|
|
if (!dmz_check_bdev(dev))
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Check super block.
|
|
*/
|
|
static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_sb *dsb,
|
|
bool tertiary)
|
|
{
|
|
struct dmz_super *sb = dsb->sb;
|
|
struct dmz_dev *dev = dsb->dev;
|
|
unsigned int nr_meta_zones, nr_data_zones;
|
|
u32 crc, stored_crc;
|
|
u64 gen, sb_block;
|
|
|
|
if (le32_to_cpu(sb->magic) != DMZ_MAGIC) {
|
|
dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)",
|
|
DMZ_MAGIC, le32_to_cpu(sb->magic));
|
|
return -ENXIO;
|
|
}
|
|
|
|
zmd->sb_version = le32_to_cpu(sb->version);
|
|
if (zmd->sb_version > DMZ_META_VER) {
|
|
dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)",
|
|
DMZ_META_VER, zmd->sb_version);
|
|
return -EINVAL;
|
|
}
|
|
if (zmd->sb_version < 2 && tertiary) {
|
|
dmz_dev_err(dev, "Tertiary superblocks are not supported");
|
|
return -EINVAL;
|
|
}
|
|
|
|
gen = le64_to_cpu(sb->gen);
|
|
stored_crc = le32_to_cpu(sb->crc);
|
|
sb->crc = 0;
|
|
crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE);
|
|
if (crc != stored_crc) {
|
|
dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)",
|
|
crc, stored_crc);
|
|
return -ENXIO;
|
|
}
|
|
|
|
sb_block = le64_to_cpu(sb->sb_block);
|
|
if (sb_block != (u64)dsb->zone->id << zmd->zone_nr_blocks_shift ) {
|
|
dmz_dev_err(dev, "Invalid superblock position "
|
|
"(is %llu expected %llu)",
|
|
sb_block,
|
|
(u64)dsb->zone->id << zmd->zone_nr_blocks_shift);
|
|
return -EINVAL;
|
|
}
|
|
if (zmd->sb_version > 1) {
|
|
uuid_t sb_uuid;
|
|
|
|
import_uuid(&sb_uuid, sb->dmz_uuid);
|
|
if (uuid_is_null(&sb_uuid)) {
|
|
dmz_dev_err(dev, "NULL DM-Zoned uuid");
|
|
return -ENXIO;
|
|
} else if (uuid_is_null(&zmd->uuid)) {
|
|
uuid_copy(&zmd->uuid, &sb_uuid);
|
|
} else if (!uuid_equal(&zmd->uuid, &sb_uuid)) {
|
|
dmz_dev_err(dev, "mismatching DM-Zoned uuid, "
|
|
"is %pUl expected %pUl",
|
|
&sb_uuid, &zmd->uuid);
|
|
return -ENXIO;
|
|
}
|
|
if (!strlen(zmd->label))
|
|
memcpy(zmd->label, sb->dmz_label, BDEVNAME_SIZE);
|
|
else if (memcmp(zmd->label, sb->dmz_label, BDEVNAME_SIZE)) {
|
|
dmz_dev_err(dev, "mismatching DM-Zoned label, "
|
|
"is %s expected %s",
|
|
sb->dmz_label, zmd->label);
|
|
return -ENXIO;
|
|
}
|
|
import_uuid(&dev->uuid, sb->dev_uuid);
|
|
if (uuid_is_null(&dev->uuid)) {
|
|
dmz_dev_err(dev, "NULL device uuid");
|
|
return -ENXIO;
|
|
}
|
|
|
|
if (tertiary) {
|
|
/*
|
|
* Generation number should be 0, but it doesn't
|
|
* really matter if it isn't.
|
|
*/
|
|
if (gen != 0)
|
|
dmz_dev_warn(dev, "Invalid generation %llu",
|
|
gen);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + zmd->zone_nr_blocks - 1)
|
|
>> zmd->zone_nr_blocks_shift;
|
|
if (!nr_meta_zones ||
|
|
(zmd->nr_devs <= 1 && nr_meta_zones >= zmd->nr_rnd_zones) ||
|
|
(zmd->nr_devs > 1 && nr_meta_zones >= zmd->nr_cache_zones)) {
|
|
dmz_dev_err(dev, "Invalid number of metadata blocks");
|
|
return -ENXIO;
|
|
}
|
|
|
|
if (!le32_to_cpu(sb->nr_reserved_seq) ||
|
|
le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) {
|
|
dmz_dev_err(dev, "Invalid number of reserved sequential zones");
|
|
return -ENXIO;
|
|
}
|
|
|
|
nr_data_zones = zmd->nr_useable_zones -
|
|
(nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq));
|
|
if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) {
|
|
dmz_dev_err(dev, "Invalid number of chunks %u / %u",
|
|
le32_to_cpu(sb->nr_chunks), nr_data_zones);
|
|
return -ENXIO;
|
|
}
|
|
|
|
/* OK */
|
|
zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks);
|
|
zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq);
|
|
zmd->nr_chunks = le32_to_cpu(sb->nr_chunks);
|
|
zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks);
|
|
zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks);
|
|
zmd->nr_meta_zones = nr_meta_zones;
|
|
zmd->nr_data_zones = nr_data_zones;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read the first or second super block from disk.
|
|
*/
|
|
static int dmz_read_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set)
|
|
{
|
|
dmz_zmd_debug(zmd, "read superblock set %d dev %pg block %llu",
|
|
set, sb->dev->bdev, sb->block);
|
|
|
|
return dmz_rdwr_block(sb->dev, REQ_OP_READ,
|
|
sb->block, sb->mblk->page);
|
|
}
|
|
|
|
/*
|
|
* Determine the position of the secondary super blocks on disk.
|
|
* This is used only if a corruption of the primary super block
|
|
* is detected.
|
|
*/
|
|
static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
|
|
{
|
|
unsigned int zone_nr_blocks = zmd->zone_nr_blocks;
|
|
struct dmz_mblock *mblk;
|
|
unsigned int zone_id = zmd->sb[0].zone->id;
|
|
int i;
|
|
|
|
/* Allocate a block */
|
|
mblk = dmz_alloc_mblock(zmd, 0);
|
|
if (!mblk)
|
|
return -ENOMEM;
|
|
|
|
zmd->sb[1].mblk = mblk;
|
|
zmd->sb[1].sb = mblk->data;
|
|
|
|
/* Bad first super block: search for the second one */
|
|
zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
|
|
zmd->sb[1].zone = dmz_get(zmd, zone_id + 1);
|
|
zmd->sb[1].dev = zmd->sb[0].dev;
|
|
for (i = 1; i < zmd->nr_rnd_zones; i++) {
|
|
if (dmz_read_sb(zmd, &zmd->sb[1], 1) != 0)
|
|
break;
|
|
if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
|
|
return 0;
|
|
zmd->sb[1].block += zone_nr_blocks;
|
|
zmd->sb[1].zone = dmz_get(zmd, zone_id + i);
|
|
}
|
|
|
|
dmz_free_mblock(zmd, mblk);
|
|
zmd->sb[1].mblk = NULL;
|
|
zmd->sb[1].zone = NULL;
|
|
zmd->sb[1].dev = NULL;
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
/*
|
|
* Read a super block from disk.
|
|
*/
|
|
static int dmz_get_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
int ret;
|
|
|
|
/* Allocate a block */
|
|
mblk = dmz_alloc_mblock(zmd, 0);
|
|
if (!mblk)
|
|
return -ENOMEM;
|
|
|
|
sb->mblk = mblk;
|
|
sb->sb = mblk->data;
|
|
|
|
/* Read super block */
|
|
ret = dmz_read_sb(zmd, sb, set);
|
|
if (ret) {
|
|
dmz_free_mblock(zmd, mblk);
|
|
sb->mblk = NULL;
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Recover a metadata set.
|
|
*/
|
|
static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
|
|
{
|
|
unsigned int src_set = dst_set ^ 0x1;
|
|
struct page *page;
|
|
int i, ret;
|
|
|
|
dmz_dev_warn(zmd->sb[dst_set].dev,
|
|
"Metadata set %u invalid: recovering", dst_set);
|
|
|
|
if (dst_set == 0)
|
|
zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
|
|
else
|
|
zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
|
|
|
|
page = alloc_page(GFP_NOIO);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
/* Copy metadata blocks */
|
|
for (i = 1; i < zmd->nr_meta_blocks; i++) {
|
|
ret = dmz_rdwr_block(zmd->sb[src_set].dev, REQ_OP_READ,
|
|
zmd->sb[src_set].block + i, page);
|
|
if (ret)
|
|
goto out;
|
|
ret = dmz_rdwr_block(zmd->sb[dst_set].dev, REQ_OP_WRITE,
|
|
zmd->sb[dst_set].block + i, page);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
/* Finalize with the super block */
|
|
if (!zmd->sb[dst_set].mblk) {
|
|
zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0);
|
|
if (!zmd->sb[dst_set].mblk) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data;
|
|
}
|
|
|
|
ret = dmz_write_sb(zmd, dst_set);
|
|
out:
|
|
__free_pages(page, 0);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Get super block from disk.
|
|
*/
|
|
static int dmz_load_sb(struct dmz_metadata *zmd)
|
|
{
|
|
bool sb_good[2] = {false, false};
|
|
u64 sb_gen[2] = {0, 0};
|
|
int ret;
|
|
|
|
if (!zmd->sb[0].zone) {
|
|
dmz_zmd_err(zmd, "Primary super block zone not set");
|
|
return -ENXIO;
|
|
}
|
|
|
|
/* Read and check the primary super block */
|
|
zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
|
|
zmd->sb[0].dev = zmd->sb[0].zone->dev;
|
|
ret = dmz_get_sb(zmd, &zmd->sb[0], 0);
|
|
if (ret) {
|
|
dmz_dev_err(zmd->sb[0].dev, "Read primary super block failed");
|
|
return ret;
|
|
}
|
|
|
|
ret = dmz_check_sb(zmd, &zmd->sb[0], false);
|
|
|
|
/* Read and check secondary super block */
|
|
if (ret == 0) {
|
|
sb_good[0] = true;
|
|
if (!zmd->sb[1].zone) {
|
|
unsigned int zone_id =
|
|
zmd->sb[0].zone->id + zmd->nr_meta_zones;
|
|
|
|
zmd->sb[1].zone = dmz_get(zmd, zone_id);
|
|
}
|
|
zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
|
|
zmd->sb[1].dev = zmd->sb[0].dev;
|
|
ret = dmz_get_sb(zmd, &zmd->sb[1], 1);
|
|
} else
|
|
ret = dmz_lookup_secondary_sb(zmd);
|
|
|
|
if (ret) {
|
|
dmz_dev_err(zmd->sb[1].dev, "Read secondary super block failed");
|
|
return ret;
|
|
}
|
|
|
|
ret = dmz_check_sb(zmd, &zmd->sb[1], false);
|
|
if (ret == 0)
|
|
sb_good[1] = true;
|
|
|
|
/* Use highest generation sb first */
|
|
if (!sb_good[0] && !sb_good[1]) {
|
|
dmz_zmd_err(zmd, "No valid super block found");
|
|
return -EIO;
|
|
}
|
|
|
|
if (sb_good[0])
|
|
sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
|
|
else {
|
|
ret = dmz_recover_mblocks(zmd, 0);
|
|
if (ret) {
|
|
dmz_dev_err(zmd->sb[0].dev,
|
|
"Recovery of superblock 0 failed");
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
if (sb_good[1])
|
|
sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
|
|
else {
|
|
ret = dmz_recover_mblocks(zmd, 1);
|
|
|
|
if (ret) {
|
|
dmz_dev_err(zmd->sb[1].dev,
|
|
"Recovery of superblock 1 failed");
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
if (sb_gen[0] >= sb_gen[1]) {
|
|
zmd->sb_gen = sb_gen[0];
|
|
zmd->mblk_primary = 0;
|
|
} else {
|
|
zmd->sb_gen = sb_gen[1];
|
|
zmd->mblk_primary = 1;
|
|
}
|
|
|
|
dmz_dev_debug(zmd->sb[zmd->mblk_primary].dev,
|
|
"Using super block %u (gen %llu)",
|
|
zmd->mblk_primary, zmd->sb_gen);
|
|
|
|
if (zmd->sb_version > 1) {
|
|
int i;
|
|
struct dmz_sb *sb;
|
|
|
|
sb = kzalloc(sizeof(struct dmz_sb), GFP_KERNEL);
|
|
if (!sb)
|
|
return -ENOMEM;
|
|
for (i = 1; i < zmd->nr_devs; i++) {
|
|
sb->block = 0;
|
|
sb->zone = dmz_get(zmd, zmd->dev[i].zone_offset);
|
|
sb->dev = &zmd->dev[i];
|
|
if (!dmz_is_meta(sb->zone)) {
|
|
dmz_dev_err(sb->dev,
|
|
"Tertiary super block zone %u not marked as metadata zone",
|
|
sb->zone->id);
|
|
ret = -EINVAL;
|
|
goto out_kfree;
|
|
}
|
|
ret = dmz_get_sb(zmd, sb, i + 1);
|
|
if (ret) {
|
|
dmz_dev_err(sb->dev,
|
|
"Read tertiary super block failed");
|
|
dmz_free_mblock(zmd, sb->mblk);
|
|
goto out_kfree;
|
|
}
|
|
ret = dmz_check_sb(zmd, sb, true);
|
|
dmz_free_mblock(zmd, sb->mblk);
|
|
if (ret == -EINVAL)
|
|
goto out_kfree;
|
|
}
|
|
out_kfree:
|
|
kfree(sb);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Initialize a zone descriptor.
|
|
*/
|
|
static int dmz_init_zone(struct blk_zone *blkz, unsigned int num, void *data)
|
|
{
|
|
struct dmz_dev *dev = data;
|
|
struct dmz_metadata *zmd = dev->metadata;
|
|
int idx = num + dev->zone_offset;
|
|
struct dm_zone *zone;
|
|
|
|
zone = dmz_insert(zmd, idx, dev);
|
|
if (IS_ERR(zone))
|
|
return PTR_ERR(zone);
|
|
|
|
if (blkz->len != zmd->zone_nr_sectors) {
|
|
if (zmd->sb_version > 1) {
|
|
/* Ignore the eventual runt (smaller) zone */
|
|
set_bit(DMZ_OFFLINE, &zone->flags);
|
|
return 0;
|
|
} else if (blkz->start + blkz->len == dev->capacity)
|
|
return 0;
|
|
return -ENXIO;
|
|
}
|
|
|
|
/*
|
|
* Devices that have zones with a capacity smaller than the zone size
|
|
* (e.g. NVMe zoned namespaces) are not supported.
|
|
*/
|
|
if (blkz->capacity != blkz->len)
|
|
return -ENXIO;
|
|
|
|
switch (blkz->type) {
|
|
case BLK_ZONE_TYPE_CONVENTIONAL:
|
|
set_bit(DMZ_RND, &zone->flags);
|
|
break;
|
|
case BLK_ZONE_TYPE_SEQWRITE_REQ:
|
|
case BLK_ZONE_TYPE_SEQWRITE_PREF:
|
|
set_bit(DMZ_SEQ, &zone->flags);
|
|
break;
|
|
default:
|
|
return -ENXIO;
|
|
}
|
|
|
|
if (dmz_is_rnd(zone))
|
|
zone->wp_block = 0;
|
|
else
|
|
zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
|
|
|
|
if (blkz->cond == BLK_ZONE_COND_OFFLINE)
|
|
set_bit(DMZ_OFFLINE, &zone->flags);
|
|
else if (blkz->cond == BLK_ZONE_COND_READONLY)
|
|
set_bit(DMZ_READ_ONLY, &zone->flags);
|
|
else {
|
|
zmd->nr_useable_zones++;
|
|
if (dmz_is_rnd(zone)) {
|
|
zmd->nr_rnd_zones++;
|
|
if (zmd->nr_devs == 1 && !zmd->sb[0].zone) {
|
|
/* Primary super block zone */
|
|
zmd->sb[0].zone = zone;
|
|
}
|
|
}
|
|
if (zmd->nr_devs > 1 && num == 0) {
|
|
/*
|
|
* Tertiary superblock zones are always at the
|
|
* start of the zoned devices, so mark them
|
|
* as metadata zone.
|
|
*/
|
|
set_bit(DMZ_META, &zone->flags);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int dmz_emulate_zones(struct dmz_metadata *zmd, struct dmz_dev *dev)
|
|
{
|
|
int idx;
|
|
sector_t zone_offset = 0;
|
|
|
|
for(idx = 0; idx < dev->nr_zones; idx++) {
|
|
struct dm_zone *zone;
|
|
|
|
zone = dmz_insert(zmd, idx, dev);
|
|
if (IS_ERR(zone))
|
|
return PTR_ERR(zone);
|
|
set_bit(DMZ_CACHE, &zone->flags);
|
|
zone->wp_block = 0;
|
|
zmd->nr_cache_zones++;
|
|
zmd->nr_useable_zones++;
|
|
if (dev->capacity - zone_offset < zmd->zone_nr_sectors) {
|
|
/* Disable runt zone */
|
|
set_bit(DMZ_OFFLINE, &zone->flags);
|
|
break;
|
|
}
|
|
zone_offset += zmd->zone_nr_sectors;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Free zones descriptors.
|
|
*/
|
|
static void dmz_drop_zones(struct dmz_metadata *zmd)
|
|
{
|
|
int idx;
|
|
|
|
for(idx = 0; idx < zmd->nr_zones; idx++) {
|
|
struct dm_zone *zone = xa_load(&zmd->zones, idx);
|
|
|
|
kfree(zone);
|
|
xa_erase(&zmd->zones, idx);
|
|
}
|
|
xa_destroy(&zmd->zones);
|
|
}
|
|
|
|
/*
|
|
* Allocate and initialize zone descriptors using the zone
|
|
* information from disk.
|
|
*/
|
|
static int dmz_init_zones(struct dmz_metadata *zmd)
|
|
{
|
|
int i, ret;
|
|
struct dmz_dev *zoned_dev = &zmd->dev[0];
|
|
|
|
/* Init */
|
|
zmd->zone_nr_sectors = zmd->dev[0].zone_nr_sectors;
|
|
zmd->zone_nr_sectors_shift = ilog2(zmd->zone_nr_sectors);
|
|
zmd->zone_nr_blocks = dmz_sect2blk(zmd->zone_nr_sectors);
|
|
zmd->zone_nr_blocks_shift = ilog2(zmd->zone_nr_blocks);
|
|
zmd->zone_bitmap_size = zmd->zone_nr_blocks >> 3;
|
|
zmd->zone_nr_bitmap_blocks =
|
|
max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT);
|
|
zmd->zone_bits_per_mblk = min_t(sector_t, zmd->zone_nr_blocks,
|
|
DMZ_BLOCK_SIZE_BITS);
|
|
|
|
/* Allocate zone array */
|
|
zmd->nr_zones = 0;
|
|
for (i = 0; i < zmd->nr_devs; i++) {
|
|
struct dmz_dev *dev = &zmd->dev[i];
|
|
|
|
dev->metadata = zmd;
|
|
zmd->nr_zones += dev->nr_zones;
|
|
|
|
atomic_set(&dev->unmap_nr_rnd, 0);
|
|
INIT_LIST_HEAD(&dev->unmap_rnd_list);
|
|
INIT_LIST_HEAD(&dev->map_rnd_list);
|
|
|
|
atomic_set(&dev->unmap_nr_seq, 0);
|
|
INIT_LIST_HEAD(&dev->unmap_seq_list);
|
|
INIT_LIST_HEAD(&dev->map_seq_list);
|
|
}
|
|
|
|
if (!zmd->nr_zones) {
|
|
DMERR("(%s): No zones found", zmd->devname);
|
|
return -ENXIO;
|
|
}
|
|
xa_init(&zmd->zones);
|
|
|
|
DMDEBUG("(%s): Using %zu B for zone information",
|
|
zmd->devname, sizeof(struct dm_zone) * zmd->nr_zones);
|
|
|
|
if (zmd->nr_devs > 1) {
|
|
ret = dmz_emulate_zones(zmd, &zmd->dev[0]);
|
|
if (ret < 0) {
|
|
DMDEBUG("(%s): Failed to emulate zones, error %d",
|
|
zmd->devname, ret);
|
|
dmz_drop_zones(zmd);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Primary superblock zone is always at zone 0 when multiple
|
|
* drives are present.
|
|
*/
|
|
zmd->sb[0].zone = dmz_get(zmd, 0);
|
|
|
|
for (i = 1; i < zmd->nr_devs; i++) {
|
|
zoned_dev = &zmd->dev[i];
|
|
|
|
ret = blkdev_report_zones(zoned_dev->bdev, 0,
|
|
BLK_ALL_ZONES,
|
|
dmz_init_zone, zoned_dev);
|
|
if (ret < 0) {
|
|
DMDEBUG("(%s): Failed to report zones, error %d",
|
|
zmd->devname, ret);
|
|
dmz_drop_zones(zmd);
|
|
return ret;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Get zone information and initialize zone descriptors. At the same
|
|
* time, determine where the super block should be: first block of the
|
|
* first randomly writable zone.
|
|
*/
|
|
ret = blkdev_report_zones(zoned_dev->bdev, 0, BLK_ALL_ZONES,
|
|
dmz_init_zone, zoned_dev);
|
|
if (ret < 0) {
|
|
DMDEBUG("(%s): Failed to report zones, error %d",
|
|
zmd->devname, ret);
|
|
dmz_drop_zones(zmd);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dmz_update_zone_cb(struct blk_zone *blkz, unsigned int idx,
|
|
void *data)
|
|
{
|
|
struct dm_zone *zone = data;
|
|
|
|
clear_bit(DMZ_OFFLINE, &zone->flags);
|
|
clear_bit(DMZ_READ_ONLY, &zone->flags);
|
|
if (blkz->cond == BLK_ZONE_COND_OFFLINE)
|
|
set_bit(DMZ_OFFLINE, &zone->flags);
|
|
else if (blkz->cond == BLK_ZONE_COND_READONLY)
|
|
set_bit(DMZ_READ_ONLY, &zone->flags);
|
|
|
|
if (dmz_is_seq(zone))
|
|
zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
|
|
else
|
|
zone->wp_block = 0;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Update a zone information.
|
|
*/
|
|
static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
struct dmz_dev *dev = zone->dev;
|
|
unsigned int noio_flag;
|
|
int ret;
|
|
|
|
if (dev->flags & DMZ_BDEV_REGULAR)
|
|
return 0;
|
|
|
|
/*
|
|
* Get zone information from disk. Since blkdev_report_zones() uses
|
|
* GFP_KERNEL by default for memory allocations, set the per-task
|
|
* PF_MEMALLOC_NOIO flag so that all allocations are done as if
|
|
* GFP_NOIO was specified.
|
|
*/
|
|
noio_flag = memalloc_noio_save();
|
|
ret = blkdev_report_zones(dev->bdev, dmz_start_sect(zmd, zone), 1,
|
|
dmz_update_zone_cb, zone);
|
|
memalloc_noio_restore(noio_flag);
|
|
|
|
if (ret == 0)
|
|
ret = -EIO;
|
|
if (ret < 0) {
|
|
dmz_dev_err(dev, "Get zone %u report failed",
|
|
zone->id);
|
|
dmz_check_bdev(dev);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check a zone write pointer position when the zone is marked
|
|
* with the sequential write error flag.
|
|
*/
|
|
static int dmz_handle_seq_write_err(struct dmz_metadata *zmd,
|
|
struct dm_zone *zone)
|
|
{
|
|
struct dmz_dev *dev = zone->dev;
|
|
unsigned int wp = 0;
|
|
int ret;
|
|
|
|
wp = zone->wp_block;
|
|
ret = dmz_update_zone(zmd, zone);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dmz_dev_warn(dev, "Processing zone %u write error (zone wp %u/%u)",
|
|
zone->id, zone->wp_block, wp);
|
|
|
|
if (zone->wp_block < wp) {
|
|
dmz_invalidate_blocks(zmd, zone, zone->wp_block,
|
|
wp - zone->wp_block);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Reset a zone write pointer.
|
|
*/
|
|
static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* Ignore offline zones, read only zones,
|
|
* and conventional zones.
|
|
*/
|
|
if (dmz_is_offline(zone) ||
|
|
dmz_is_readonly(zone) ||
|
|
dmz_is_rnd(zone))
|
|
return 0;
|
|
|
|
if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) {
|
|
struct dmz_dev *dev = zone->dev;
|
|
|
|
ret = blkdev_zone_mgmt(dev->bdev, REQ_OP_ZONE_RESET,
|
|
dmz_start_sect(zmd, zone),
|
|
zmd->zone_nr_sectors, GFP_NOIO);
|
|
if (ret) {
|
|
dmz_dev_err(dev, "Reset zone %u failed %d",
|
|
zone->id, ret);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Clear write error bit and rewind write pointer position */
|
|
clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
|
|
zone->wp_block = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone);
|
|
|
|
/*
|
|
* Initialize chunk mapping.
|
|
*/
|
|
static int dmz_load_mapping(struct dmz_metadata *zmd)
|
|
{
|
|
struct dm_zone *dzone, *bzone;
|
|
struct dmz_mblock *dmap_mblk = NULL;
|
|
struct dmz_map *dmap;
|
|
unsigned int i = 0, e = 0, chunk = 0;
|
|
unsigned int dzone_id;
|
|
unsigned int bzone_id;
|
|
|
|
/* Metadata block array for the chunk mapping table */
|
|
zmd->map_mblk = kcalloc(zmd->nr_map_blocks,
|
|
sizeof(struct dmz_mblk *), GFP_KERNEL);
|
|
if (!zmd->map_mblk)
|
|
return -ENOMEM;
|
|
|
|
/* Get chunk mapping table blocks and initialize zone mapping */
|
|
while (chunk < zmd->nr_chunks) {
|
|
if (!dmap_mblk) {
|
|
/* Get mapping block */
|
|
dmap_mblk = dmz_get_mblock(zmd, i + 1);
|
|
if (IS_ERR(dmap_mblk))
|
|
return PTR_ERR(dmap_mblk);
|
|
zmd->map_mblk[i] = dmap_mblk;
|
|
dmap = (struct dmz_map *) dmap_mblk->data;
|
|
i++;
|
|
e = 0;
|
|
}
|
|
|
|
/* Check data zone */
|
|
dzone_id = le32_to_cpu(dmap[e].dzone_id);
|
|
if (dzone_id == DMZ_MAP_UNMAPPED)
|
|
goto next;
|
|
|
|
if (dzone_id >= zmd->nr_zones) {
|
|
dmz_zmd_err(zmd, "Chunk %u mapping: invalid data zone ID %u",
|
|
chunk, dzone_id);
|
|
return -EIO;
|
|
}
|
|
|
|
dzone = dmz_get(zmd, dzone_id);
|
|
if (!dzone) {
|
|
dmz_zmd_err(zmd, "Chunk %u mapping: data zone %u not present",
|
|
chunk, dzone_id);
|
|
return -EIO;
|
|
}
|
|
set_bit(DMZ_DATA, &dzone->flags);
|
|
dzone->chunk = chunk;
|
|
dmz_get_zone_weight(zmd, dzone);
|
|
|
|
if (dmz_is_cache(dzone))
|
|
list_add_tail(&dzone->link, &zmd->map_cache_list);
|
|
else if (dmz_is_rnd(dzone))
|
|
list_add_tail(&dzone->link, &dzone->dev->map_rnd_list);
|
|
else
|
|
list_add_tail(&dzone->link, &dzone->dev->map_seq_list);
|
|
|
|
/* Check buffer zone */
|
|
bzone_id = le32_to_cpu(dmap[e].bzone_id);
|
|
if (bzone_id == DMZ_MAP_UNMAPPED)
|
|
goto next;
|
|
|
|
if (bzone_id >= zmd->nr_zones) {
|
|
dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone ID %u",
|
|
chunk, bzone_id);
|
|
return -EIO;
|
|
}
|
|
|
|
bzone = dmz_get(zmd, bzone_id);
|
|
if (!bzone) {
|
|
dmz_zmd_err(zmd, "Chunk %u mapping: buffer zone %u not present",
|
|
chunk, bzone_id);
|
|
return -EIO;
|
|
}
|
|
if (!dmz_is_rnd(bzone) && !dmz_is_cache(bzone)) {
|
|
dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone %u",
|
|
chunk, bzone_id);
|
|
return -EIO;
|
|
}
|
|
|
|
set_bit(DMZ_DATA, &bzone->flags);
|
|
set_bit(DMZ_BUF, &bzone->flags);
|
|
bzone->chunk = chunk;
|
|
bzone->bzone = dzone;
|
|
dzone->bzone = bzone;
|
|
dmz_get_zone_weight(zmd, bzone);
|
|
if (dmz_is_cache(bzone))
|
|
list_add_tail(&bzone->link, &zmd->map_cache_list);
|
|
else
|
|
list_add_tail(&bzone->link, &bzone->dev->map_rnd_list);
|
|
next:
|
|
chunk++;
|
|
e++;
|
|
if (e >= DMZ_MAP_ENTRIES)
|
|
dmap_mblk = NULL;
|
|
}
|
|
|
|
/*
|
|
* At this point, only meta zones and mapped data zones were
|
|
* fully initialized. All remaining zones are unmapped data
|
|
* zones. Finish initializing those here.
|
|
*/
|
|
for (i = 0; i < zmd->nr_zones; i++) {
|
|
dzone = dmz_get(zmd, i);
|
|
if (!dzone)
|
|
continue;
|
|
if (dmz_is_meta(dzone))
|
|
continue;
|
|
if (dmz_is_offline(dzone))
|
|
continue;
|
|
|
|
if (dmz_is_cache(dzone))
|
|
zmd->nr_cache++;
|
|
else if (dmz_is_rnd(dzone))
|
|
dzone->dev->nr_rnd++;
|
|
else
|
|
dzone->dev->nr_seq++;
|
|
|
|
if (dmz_is_data(dzone)) {
|
|
/* Already initialized */
|
|
continue;
|
|
}
|
|
|
|
/* Unmapped data zone */
|
|
set_bit(DMZ_DATA, &dzone->flags);
|
|
dzone->chunk = DMZ_MAP_UNMAPPED;
|
|
if (dmz_is_cache(dzone)) {
|
|
list_add_tail(&dzone->link, &zmd->unmap_cache_list);
|
|
atomic_inc(&zmd->unmap_nr_cache);
|
|
} else if (dmz_is_rnd(dzone)) {
|
|
list_add_tail(&dzone->link,
|
|
&dzone->dev->unmap_rnd_list);
|
|
atomic_inc(&dzone->dev->unmap_nr_rnd);
|
|
} else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) {
|
|
list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list);
|
|
set_bit(DMZ_RESERVED, &dzone->flags);
|
|
atomic_inc(&zmd->nr_reserved_seq_zones);
|
|
dzone->dev->nr_seq--;
|
|
} else {
|
|
list_add_tail(&dzone->link,
|
|
&dzone->dev->unmap_seq_list);
|
|
atomic_inc(&dzone->dev->unmap_nr_seq);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Set a data chunk mapping.
|
|
*/
|
|
static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk,
|
|
unsigned int dzone_id, unsigned int bzone_id)
|
|
{
|
|
struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
|
|
struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
|
|
int map_idx = chunk & DMZ_MAP_ENTRIES_MASK;
|
|
|
|
dmap[map_idx].dzone_id = cpu_to_le32(dzone_id);
|
|
dmap[map_idx].bzone_id = cpu_to_le32(bzone_id);
|
|
dmz_dirty_mblock(zmd, dmap_mblk);
|
|
}
|
|
|
|
/*
|
|
* The list of mapped zones is maintained in LRU order.
|
|
* This rotates a zone at the end of its map list.
|
|
*/
|
|
static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
if (list_empty(&zone->link))
|
|
return;
|
|
|
|
list_del_init(&zone->link);
|
|
if (dmz_is_seq(zone)) {
|
|
/* LRU rotate sequential zone */
|
|
list_add_tail(&zone->link, &zone->dev->map_seq_list);
|
|
} else if (dmz_is_cache(zone)) {
|
|
/* LRU rotate cache zone */
|
|
list_add_tail(&zone->link, &zmd->map_cache_list);
|
|
} else {
|
|
/* LRU rotate random zone */
|
|
list_add_tail(&zone->link, &zone->dev->map_rnd_list);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* The list of mapped random zones is maintained
|
|
* in LRU order. This rotates a zone at the end of the list.
|
|
*/
|
|
static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
__dmz_lru_zone(zmd, zone);
|
|
if (zone->bzone)
|
|
__dmz_lru_zone(zmd, zone->bzone);
|
|
}
|
|
|
|
/*
|
|
* Wait for any zone to be freed.
|
|
*/
|
|
static void dmz_wait_for_free_zones(struct dmz_metadata *zmd)
|
|
{
|
|
DEFINE_WAIT(wait);
|
|
|
|
prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE);
|
|
dmz_unlock_map(zmd);
|
|
dmz_unlock_metadata(zmd);
|
|
|
|
io_schedule_timeout(HZ);
|
|
|
|
dmz_lock_metadata(zmd);
|
|
dmz_lock_map(zmd);
|
|
finish_wait(&zmd->free_wq, &wait);
|
|
}
|
|
|
|
/*
|
|
* Lock a zone for reclaim (set the zone RECLAIM bit).
|
|
* Returns false if the zone cannot be locked or if it is already locked
|
|
* and 1 otherwise.
|
|
*/
|
|
int dmz_lock_zone_reclaim(struct dm_zone *zone)
|
|
{
|
|
/* Active zones cannot be reclaimed */
|
|
if (dmz_is_active(zone))
|
|
return 0;
|
|
|
|
return !test_and_set_bit(DMZ_RECLAIM, &zone->flags);
|
|
}
|
|
|
|
/*
|
|
* Clear a zone reclaim flag.
|
|
*/
|
|
void dmz_unlock_zone_reclaim(struct dm_zone *zone)
|
|
{
|
|
WARN_ON(dmz_is_active(zone));
|
|
WARN_ON(!dmz_in_reclaim(zone));
|
|
|
|
clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
|
|
smp_mb__after_atomic();
|
|
wake_up_bit(&zone->flags, DMZ_RECLAIM);
|
|
}
|
|
|
|
/*
|
|
* Wait for a zone reclaim to complete.
|
|
*/
|
|
static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
dmz_unlock_map(zmd);
|
|
dmz_unlock_metadata(zmd);
|
|
set_bit(DMZ_RECLAIM_TERMINATE, &zone->flags);
|
|
wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ);
|
|
clear_bit(DMZ_RECLAIM_TERMINATE, &zone->flags);
|
|
dmz_lock_metadata(zmd);
|
|
dmz_lock_map(zmd);
|
|
}
|
|
|
|
/*
|
|
* Select a cache or random write zone for reclaim.
|
|
*/
|
|
static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd,
|
|
unsigned int idx, bool idle)
|
|
{
|
|
struct dm_zone *dzone = NULL;
|
|
struct dm_zone *zone, *maxw_z = NULL;
|
|
struct list_head *zone_list;
|
|
|
|
/* If we have cache zones select from the cache zone list */
|
|
if (zmd->nr_cache) {
|
|
zone_list = &zmd->map_cache_list;
|
|
/* Try to relaim random zones, too, when idle */
|
|
if (idle && list_empty(zone_list))
|
|
zone_list = &zmd->dev[idx].map_rnd_list;
|
|
} else
|
|
zone_list = &zmd->dev[idx].map_rnd_list;
|
|
|
|
/*
|
|
* Find the buffer zone with the heaviest weight or the first (oldest)
|
|
* data zone that can be reclaimed.
|
|
*/
|
|
list_for_each_entry(zone, zone_list, link) {
|
|
if (dmz_is_buf(zone)) {
|
|
dzone = zone->bzone;
|
|
if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx)
|
|
continue;
|
|
if (!maxw_z || maxw_z->weight < dzone->weight)
|
|
maxw_z = dzone;
|
|
} else {
|
|
dzone = zone;
|
|
if (dmz_lock_zone_reclaim(dzone))
|
|
return dzone;
|
|
}
|
|
}
|
|
|
|
if (maxw_z && dmz_lock_zone_reclaim(maxw_z))
|
|
return maxw_z;
|
|
|
|
/*
|
|
* If we come here, none of the zones inspected could be locked for
|
|
* reclaim. Try again, being more aggressive, that is, find the
|
|
* first zone that can be reclaimed regardless of its weitght.
|
|
*/
|
|
list_for_each_entry(zone, zone_list, link) {
|
|
if (dmz_is_buf(zone)) {
|
|
dzone = zone->bzone;
|
|
if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx)
|
|
continue;
|
|
} else
|
|
dzone = zone;
|
|
if (dmz_lock_zone_reclaim(dzone))
|
|
return dzone;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Select a buffered sequential zone for reclaim.
|
|
*/
|
|
static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd,
|
|
unsigned int idx)
|
|
{
|
|
struct dm_zone *zone;
|
|
|
|
list_for_each_entry(zone, &zmd->dev[idx].map_seq_list, link) {
|
|
if (!zone->bzone)
|
|
continue;
|
|
if (dmz_lock_zone_reclaim(zone))
|
|
return zone;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Select a zone for reclaim.
|
|
*/
|
|
struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd,
|
|
unsigned int dev_idx, bool idle)
|
|
{
|
|
struct dm_zone *zone = NULL;
|
|
|
|
/*
|
|
* Search for a zone candidate to reclaim: 2 cases are possible.
|
|
* (1) There is no free sequential zones. Then a random data zone
|
|
* cannot be reclaimed. So choose a sequential zone to reclaim so
|
|
* that afterward a random zone can be reclaimed.
|
|
* (2) At least one free sequential zone is available, then choose
|
|
* the oldest random zone (data or buffer) that can be locked.
|
|
*/
|
|
dmz_lock_map(zmd);
|
|
if (list_empty(&zmd->reserved_seq_zones_list))
|
|
zone = dmz_get_seq_zone_for_reclaim(zmd, dev_idx);
|
|
if (!zone)
|
|
zone = dmz_get_rnd_zone_for_reclaim(zmd, dev_idx, idle);
|
|
dmz_unlock_map(zmd);
|
|
|
|
return zone;
|
|
}
|
|
|
|
/*
|
|
* Get the zone mapping a chunk, if the chunk is mapped already.
|
|
* If no mapping exist and the operation is WRITE, a zone is
|
|
* allocated and used to map the chunk.
|
|
* The zone returned will be set to the active state.
|
|
*/
|
|
struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op)
|
|
{
|
|
struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
|
|
struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
|
|
int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK;
|
|
unsigned int dzone_id;
|
|
struct dm_zone *dzone = NULL;
|
|
int ret = 0;
|
|
int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
|
|
|
|
dmz_lock_map(zmd);
|
|
again:
|
|
/* Get the chunk mapping */
|
|
dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id);
|
|
if (dzone_id == DMZ_MAP_UNMAPPED) {
|
|
/*
|
|
* Read or discard in unmapped chunks are fine. But for
|
|
* writes, we need a mapping, so get one.
|
|
*/
|
|
if (op != REQ_OP_WRITE)
|
|
goto out;
|
|
|
|
/* Allocate a random zone */
|
|
dzone = dmz_alloc_zone(zmd, 0, alloc_flags);
|
|
if (!dzone) {
|
|
if (dmz_dev_is_dying(zmd)) {
|
|
dzone = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
dmz_wait_for_free_zones(zmd);
|
|
goto again;
|
|
}
|
|
|
|
dmz_map_zone(zmd, dzone, chunk);
|
|
|
|
} else {
|
|
/* The chunk is already mapped: get the mapping zone */
|
|
dzone = dmz_get(zmd, dzone_id);
|
|
if (!dzone) {
|
|
dzone = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
if (dzone->chunk != chunk) {
|
|
dzone = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
|
|
/* Repair write pointer if the sequential dzone has error */
|
|
if (dmz_seq_write_err(dzone)) {
|
|
ret = dmz_handle_seq_write_err(zmd, dzone);
|
|
if (ret) {
|
|
dzone = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If the zone is being reclaimed, the chunk mapping may change
|
|
* to a different zone. So wait for reclaim and retry. Otherwise,
|
|
* activate the zone (this will prevent reclaim from touching it).
|
|
*/
|
|
if (dmz_in_reclaim(dzone)) {
|
|
dmz_wait_for_reclaim(zmd, dzone);
|
|
goto again;
|
|
}
|
|
dmz_activate_zone(dzone);
|
|
dmz_lru_zone(zmd, dzone);
|
|
out:
|
|
dmz_unlock_map(zmd);
|
|
|
|
return dzone;
|
|
}
|
|
|
|
/*
|
|
* Write and discard change the block validity of data zones and their buffer
|
|
* zones. Check here that valid blocks are still present. If all blocks are
|
|
* invalid, the zones can be unmapped on the fly without waiting for reclaim
|
|
* to do it.
|
|
*/
|
|
void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone)
|
|
{
|
|
struct dm_zone *bzone;
|
|
|
|
dmz_lock_map(zmd);
|
|
|
|
bzone = dzone->bzone;
|
|
if (bzone) {
|
|
if (dmz_weight(bzone))
|
|
dmz_lru_zone(zmd, bzone);
|
|
else {
|
|
/* Empty buffer zone: reclaim it */
|
|
dmz_unmap_zone(zmd, bzone);
|
|
dmz_free_zone(zmd, bzone);
|
|
bzone = NULL;
|
|
}
|
|
}
|
|
|
|
/* Deactivate the data zone */
|
|
dmz_deactivate_zone(dzone);
|
|
if (dmz_is_active(dzone) || bzone || dmz_weight(dzone))
|
|
dmz_lru_zone(zmd, dzone);
|
|
else {
|
|
/* Unbuffered inactive empty data zone: reclaim it */
|
|
dmz_unmap_zone(zmd, dzone);
|
|
dmz_free_zone(zmd, dzone);
|
|
}
|
|
|
|
dmz_unlock_map(zmd);
|
|
}
|
|
|
|
/*
|
|
* Allocate and map a random zone to buffer a chunk
|
|
* already mapped to a sequential zone.
|
|
*/
|
|
struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
|
|
struct dm_zone *dzone)
|
|
{
|
|
struct dm_zone *bzone;
|
|
int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
|
|
|
|
dmz_lock_map(zmd);
|
|
again:
|
|
bzone = dzone->bzone;
|
|
if (bzone)
|
|
goto out;
|
|
|
|
/* Allocate a random zone */
|
|
bzone = dmz_alloc_zone(zmd, 0, alloc_flags);
|
|
if (!bzone) {
|
|
if (dmz_dev_is_dying(zmd)) {
|
|
bzone = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
dmz_wait_for_free_zones(zmd);
|
|
goto again;
|
|
}
|
|
|
|
/* Update the chunk mapping */
|
|
dmz_set_chunk_mapping(zmd, dzone->chunk, dzone->id, bzone->id);
|
|
|
|
set_bit(DMZ_BUF, &bzone->flags);
|
|
bzone->chunk = dzone->chunk;
|
|
bzone->bzone = dzone;
|
|
dzone->bzone = bzone;
|
|
if (dmz_is_cache(bzone))
|
|
list_add_tail(&bzone->link, &zmd->map_cache_list);
|
|
else
|
|
list_add_tail(&bzone->link, &bzone->dev->map_rnd_list);
|
|
out:
|
|
dmz_unlock_map(zmd);
|
|
|
|
return bzone;
|
|
}
|
|
|
|
/*
|
|
* Get an unmapped (free) zone.
|
|
* This must be called with the mapping lock held.
|
|
*/
|
|
struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned int dev_idx,
|
|
unsigned long flags)
|
|
{
|
|
struct list_head *list;
|
|
struct dm_zone *zone;
|
|
int i;
|
|
|
|
/* Schedule reclaim to ensure free zones are available */
|
|
if (!(flags & DMZ_ALLOC_RECLAIM)) {
|
|
for (i = 0; i < zmd->nr_devs; i++)
|
|
dmz_schedule_reclaim(zmd->dev[i].reclaim);
|
|
}
|
|
|
|
i = 0;
|
|
again:
|
|
if (flags & DMZ_ALLOC_CACHE)
|
|
list = &zmd->unmap_cache_list;
|
|
else if (flags & DMZ_ALLOC_RND)
|
|
list = &zmd->dev[dev_idx].unmap_rnd_list;
|
|
else
|
|
list = &zmd->dev[dev_idx].unmap_seq_list;
|
|
|
|
if (list_empty(list)) {
|
|
/*
|
|
* No free zone: return NULL if this is for not reclaim.
|
|
*/
|
|
if (!(flags & DMZ_ALLOC_RECLAIM))
|
|
return NULL;
|
|
/*
|
|
* Try to allocate from other devices
|
|
*/
|
|
if (i < zmd->nr_devs) {
|
|
dev_idx = (dev_idx + 1) % zmd->nr_devs;
|
|
i++;
|
|
goto again;
|
|
}
|
|
|
|
/*
|
|
* Fallback to the reserved sequential zones
|
|
*/
|
|
zone = list_first_entry_or_null(&zmd->reserved_seq_zones_list,
|
|
struct dm_zone, link);
|
|
if (zone) {
|
|
list_del_init(&zone->link);
|
|
atomic_dec(&zmd->nr_reserved_seq_zones);
|
|
}
|
|
return zone;
|
|
}
|
|
|
|
zone = list_first_entry(list, struct dm_zone, link);
|
|
list_del_init(&zone->link);
|
|
|
|
if (dmz_is_cache(zone))
|
|
atomic_dec(&zmd->unmap_nr_cache);
|
|
else if (dmz_is_rnd(zone))
|
|
atomic_dec(&zone->dev->unmap_nr_rnd);
|
|
else
|
|
atomic_dec(&zone->dev->unmap_nr_seq);
|
|
|
|
if (dmz_is_offline(zone)) {
|
|
dmz_zmd_warn(zmd, "Zone %u is offline", zone->id);
|
|
zone = NULL;
|
|
goto again;
|
|
}
|
|
if (dmz_is_meta(zone)) {
|
|
dmz_zmd_warn(zmd, "Zone %u has metadata", zone->id);
|
|
zone = NULL;
|
|
goto again;
|
|
}
|
|
return zone;
|
|
}
|
|
|
|
/*
|
|
* Free a zone.
|
|
* This must be called with the mapping lock held.
|
|
*/
|
|
void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
/* If this is a sequential zone, reset it */
|
|
if (dmz_is_seq(zone))
|
|
dmz_reset_zone(zmd, zone);
|
|
|
|
/* Return the zone to its type unmap list */
|
|
if (dmz_is_cache(zone)) {
|
|
list_add_tail(&zone->link, &zmd->unmap_cache_list);
|
|
atomic_inc(&zmd->unmap_nr_cache);
|
|
} else if (dmz_is_rnd(zone)) {
|
|
list_add_tail(&zone->link, &zone->dev->unmap_rnd_list);
|
|
atomic_inc(&zone->dev->unmap_nr_rnd);
|
|
} else if (dmz_is_reserved(zone)) {
|
|
list_add_tail(&zone->link, &zmd->reserved_seq_zones_list);
|
|
atomic_inc(&zmd->nr_reserved_seq_zones);
|
|
} else {
|
|
list_add_tail(&zone->link, &zone->dev->unmap_seq_list);
|
|
atomic_inc(&zone->dev->unmap_nr_seq);
|
|
}
|
|
|
|
wake_up_all(&zmd->free_wq);
|
|
}
|
|
|
|
/*
|
|
* Map a chunk to a zone.
|
|
* This must be called with the mapping lock held.
|
|
*/
|
|
void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone,
|
|
unsigned int chunk)
|
|
{
|
|
/* Set the chunk mapping */
|
|
dmz_set_chunk_mapping(zmd, chunk, dzone->id,
|
|
DMZ_MAP_UNMAPPED);
|
|
dzone->chunk = chunk;
|
|
if (dmz_is_cache(dzone))
|
|
list_add_tail(&dzone->link, &zmd->map_cache_list);
|
|
else if (dmz_is_rnd(dzone))
|
|
list_add_tail(&dzone->link, &dzone->dev->map_rnd_list);
|
|
else
|
|
list_add_tail(&dzone->link, &dzone->dev->map_seq_list);
|
|
}
|
|
|
|
/*
|
|
* Unmap a zone.
|
|
* This must be called with the mapping lock held.
|
|
*/
|
|
void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
unsigned int chunk = zone->chunk;
|
|
unsigned int dzone_id;
|
|
|
|
if (chunk == DMZ_MAP_UNMAPPED) {
|
|
/* Already unmapped */
|
|
return;
|
|
}
|
|
|
|
if (test_and_clear_bit(DMZ_BUF, &zone->flags)) {
|
|
/*
|
|
* Unmapping the chunk buffer zone: clear only
|
|
* the chunk buffer mapping
|
|
*/
|
|
dzone_id = zone->bzone->id;
|
|
zone->bzone->bzone = NULL;
|
|
zone->bzone = NULL;
|
|
|
|
} else {
|
|
/*
|
|
* Unmapping the chunk data zone: the zone must
|
|
* not be buffered.
|
|
*/
|
|
if (WARN_ON(zone->bzone)) {
|
|
zone->bzone->bzone = NULL;
|
|
zone->bzone = NULL;
|
|
}
|
|
dzone_id = DMZ_MAP_UNMAPPED;
|
|
}
|
|
|
|
dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED);
|
|
|
|
zone->chunk = DMZ_MAP_UNMAPPED;
|
|
list_del_init(&zone->link);
|
|
}
|
|
|
|
/*
|
|
* Set @nr_bits bits in @bitmap starting from @bit.
|
|
* Return the number of bits changed from 0 to 1.
|
|
*/
|
|
static unsigned int dmz_set_bits(unsigned long *bitmap,
|
|
unsigned int bit, unsigned int nr_bits)
|
|
{
|
|
unsigned long *addr;
|
|
unsigned int end = bit + nr_bits;
|
|
unsigned int n = 0;
|
|
|
|
while (bit < end) {
|
|
if (((bit & (BITS_PER_LONG - 1)) == 0) &&
|
|
((end - bit) >= BITS_PER_LONG)) {
|
|
/* Try to set the whole word at once */
|
|
addr = bitmap + BIT_WORD(bit);
|
|
if (*addr == 0) {
|
|
*addr = ULONG_MAX;
|
|
n += BITS_PER_LONG;
|
|
bit += BITS_PER_LONG;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (!test_and_set_bit(bit, bitmap))
|
|
n++;
|
|
bit++;
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* Get the bitmap block storing the bit for chunk_block in zone.
|
|
*/
|
|
static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd,
|
|
struct dm_zone *zone,
|
|
sector_t chunk_block)
|
|
{
|
|
sector_t bitmap_block = 1 + zmd->nr_map_blocks +
|
|
(sector_t)(zone->id * zmd->zone_nr_bitmap_blocks) +
|
|
(chunk_block >> DMZ_BLOCK_SHIFT_BITS);
|
|
|
|
return dmz_get_mblock(zmd, bitmap_block);
|
|
}
|
|
|
|
/*
|
|
* Copy the valid blocks bitmap of from_zone to the bitmap of to_zone.
|
|
*/
|
|
int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
|
|
struct dm_zone *to_zone)
|
|
{
|
|
struct dmz_mblock *from_mblk, *to_mblk;
|
|
sector_t chunk_block = 0;
|
|
|
|
/* Get the zones bitmap blocks */
|
|
while (chunk_block < zmd->zone_nr_blocks) {
|
|
from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block);
|
|
if (IS_ERR(from_mblk))
|
|
return PTR_ERR(from_mblk);
|
|
to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block);
|
|
if (IS_ERR(to_mblk)) {
|
|
dmz_release_mblock(zmd, from_mblk);
|
|
return PTR_ERR(to_mblk);
|
|
}
|
|
|
|
memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE);
|
|
dmz_dirty_mblock(zmd, to_mblk);
|
|
|
|
dmz_release_mblock(zmd, to_mblk);
|
|
dmz_release_mblock(zmd, from_mblk);
|
|
|
|
chunk_block += zmd->zone_bits_per_mblk;
|
|
}
|
|
|
|
to_zone->weight = from_zone->weight;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Merge the valid blocks bitmap of from_zone into the bitmap of to_zone,
|
|
* starting from chunk_block.
|
|
*/
|
|
int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
|
|
struct dm_zone *to_zone, sector_t chunk_block)
|
|
{
|
|
unsigned int nr_blocks;
|
|
int ret;
|
|
|
|
/* Get the zones bitmap blocks */
|
|
while (chunk_block < zmd->zone_nr_blocks) {
|
|
/* Get a valid region from the source zone */
|
|
ret = dmz_first_valid_block(zmd, from_zone, &chunk_block);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
nr_blocks = ret;
|
|
ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks);
|
|
if (ret)
|
|
return ret;
|
|
|
|
chunk_block += nr_blocks;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Validate all the blocks in the range [block..block+nr_blocks-1].
|
|
*/
|
|
int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t chunk_block, unsigned int nr_blocks)
|
|
{
|
|
unsigned int count, bit, nr_bits;
|
|
unsigned int zone_nr_blocks = zmd->zone_nr_blocks;
|
|
struct dmz_mblock *mblk;
|
|
unsigned int n = 0;
|
|
|
|
dmz_zmd_debug(zmd, "=> VALIDATE zone %u, block %llu, %u blocks",
|
|
zone->id, (unsigned long long)chunk_block,
|
|
nr_blocks);
|
|
|
|
WARN_ON(chunk_block + nr_blocks > zone_nr_blocks);
|
|
|
|
while (nr_blocks) {
|
|
/* Get bitmap block */
|
|
mblk = dmz_get_bitmap(zmd, zone, chunk_block);
|
|
if (IS_ERR(mblk))
|
|
return PTR_ERR(mblk);
|
|
|
|
/* Set bits */
|
|
bit = chunk_block & DMZ_BLOCK_MASK_BITS;
|
|
nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
|
|
|
|
count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits);
|
|
if (count) {
|
|
dmz_dirty_mblock(zmd, mblk);
|
|
n += count;
|
|
}
|
|
dmz_release_mblock(zmd, mblk);
|
|
|
|
nr_blocks -= nr_bits;
|
|
chunk_block += nr_bits;
|
|
}
|
|
|
|
if (likely(zone->weight + n <= zone_nr_blocks))
|
|
zone->weight += n;
|
|
else {
|
|
dmz_zmd_warn(zmd, "Zone %u: weight %u should be <= %u",
|
|
zone->id, zone->weight,
|
|
zone_nr_blocks - n);
|
|
zone->weight = zone_nr_blocks;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Clear nr_bits bits in bitmap starting from bit.
|
|
* Return the number of bits cleared.
|
|
*/
|
|
static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits)
|
|
{
|
|
unsigned long *addr;
|
|
int end = bit + nr_bits;
|
|
int n = 0;
|
|
|
|
while (bit < end) {
|
|
if (((bit & (BITS_PER_LONG - 1)) == 0) &&
|
|
((end - bit) >= BITS_PER_LONG)) {
|
|
/* Try to clear whole word at once */
|
|
addr = bitmap + BIT_WORD(bit);
|
|
if (*addr == ULONG_MAX) {
|
|
*addr = 0;
|
|
n += BITS_PER_LONG;
|
|
bit += BITS_PER_LONG;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (test_and_clear_bit(bit, bitmap))
|
|
n++;
|
|
bit++;
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* Invalidate all the blocks in the range [block..block+nr_blocks-1].
|
|
*/
|
|
int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t chunk_block, unsigned int nr_blocks)
|
|
{
|
|
unsigned int count, bit, nr_bits;
|
|
struct dmz_mblock *mblk;
|
|
unsigned int n = 0;
|
|
|
|
dmz_zmd_debug(zmd, "=> INVALIDATE zone %u, block %llu, %u blocks",
|
|
zone->id, (u64)chunk_block, nr_blocks);
|
|
|
|
WARN_ON(chunk_block + nr_blocks > zmd->zone_nr_blocks);
|
|
|
|
while (nr_blocks) {
|
|
/* Get bitmap block */
|
|
mblk = dmz_get_bitmap(zmd, zone, chunk_block);
|
|
if (IS_ERR(mblk))
|
|
return PTR_ERR(mblk);
|
|
|
|
/* Clear bits */
|
|
bit = chunk_block & DMZ_BLOCK_MASK_BITS;
|
|
nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
|
|
|
|
count = dmz_clear_bits((unsigned long *)mblk->data,
|
|
bit, nr_bits);
|
|
if (count) {
|
|
dmz_dirty_mblock(zmd, mblk);
|
|
n += count;
|
|
}
|
|
dmz_release_mblock(zmd, mblk);
|
|
|
|
nr_blocks -= nr_bits;
|
|
chunk_block += nr_bits;
|
|
}
|
|
|
|
if (zone->weight >= n)
|
|
zone->weight -= n;
|
|
else {
|
|
dmz_zmd_warn(zmd, "Zone %u: weight %u should be >= %u",
|
|
zone->id, zone->weight, n);
|
|
zone->weight = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Get a block bit value.
|
|
*/
|
|
static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t chunk_block)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
int ret;
|
|
|
|
WARN_ON(chunk_block >= zmd->zone_nr_blocks);
|
|
|
|
/* Get bitmap block */
|
|
mblk = dmz_get_bitmap(zmd, zone, chunk_block);
|
|
if (IS_ERR(mblk))
|
|
return PTR_ERR(mblk);
|
|
|
|
/* Get offset */
|
|
ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS,
|
|
(unsigned long *) mblk->data) != 0;
|
|
|
|
dmz_release_mblock(zmd, mblk);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Return the number of blocks from chunk_block to the first block with a bit
|
|
* value specified by set. Search at most nr_blocks blocks from chunk_block.
|
|
*/
|
|
static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t chunk_block, unsigned int nr_blocks,
|
|
int set)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
unsigned int bit, set_bit, nr_bits;
|
|
unsigned int zone_bits = zmd->zone_bits_per_mblk;
|
|
unsigned long *bitmap;
|
|
int n = 0;
|
|
|
|
WARN_ON(chunk_block + nr_blocks > zmd->zone_nr_blocks);
|
|
|
|
while (nr_blocks) {
|
|
/* Get bitmap block */
|
|
mblk = dmz_get_bitmap(zmd, zone, chunk_block);
|
|
if (IS_ERR(mblk))
|
|
return PTR_ERR(mblk);
|
|
|
|
/* Get offset */
|
|
bitmap = (unsigned long *) mblk->data;
|
|
bit = chunk_block & DMZ_BLOCK_MASK_BITS;
|
|
nr_bits = min(nr_blocks, zone_bits - bit);
|
|
if (set)
|
|
set_bit = find_next_bit(bitmap, zone_bits, bit);
|
|
else
|
|
set_bit = find_next_zero_bit(bitmap, zone_bits, bit);
|
|
dmz_release_mblock(zmd, mblk);
|
|
|
|
n += set_bit - bit;
|
|
if (set_bit < zone_bits)
|
|
break;
|
|
|
|
nr_blocks -= nr_bits;
|
|
chunk_block += nr_bits;
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* Test if chunk_block is valid. If it is, the number of consecutive
|
|
* valid blocks from chunk_block will be returned.
|
|
*/
|
|
int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t chunk_block)
|
|
{
|
|
int valid;
|
|
|
|
valid = dmz_test_block(zmd, zone, chunk_block);
|
|
if (valid <= 0)
|
|
return valid;
|
|
|
|
/* The block is valid: get the number of valid blocks from block */
|
|
return dmz_to_next_set_block(zmd, zone, chunk_block,
|
|
zmd->zone_nr_blocks - chunk_block, 0);
|
|
}
|
|
|
|
/*
|
|
* Find the first valid block from @chunk_block in @zone.
|
|
* If such a block is found, its number is returned using
|
|
* @chunk_block and the total number of valid blocks from @chunk_block
|
|
* is returned.
|
|
*/
|
|
int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
|
|
sector_t *chunk_block)
|
|
{
|
|
sector_t start_block = *chunk_block;
|
|
int ret;
|
|
|
|
ret = dmz_to_next_set_block(zmd, zone, start_block,
|
|
zmd->zone_nr_blocks - start_block, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
start_block += ret;
|
|
*chunk_block = start_block;
|
|
|
|
return dmz_to_next_set_block(zmd, zone, start_block,
|
|
zmd->zone_nr_blocks - start_block, 0);
|
|
}
|
|
|
|
/*
|
|
* Count the number of bits set starting from bit up to bit + nr_bits - 1.
|
|
*/
|
|
static int dmz_count_bits(void *bitmap, int bit, int nr_bits)
|
|
{
|
|
unsigned long *addr;
|
|
int end = bit + nr_bits;
|
|
int n = 0;
|
|
|
|
while (bit < end) {
|
|
if (((bit & (BITS_PER_LONG - 1)) == 0) &&
|
|
((end - bit) >= BITS_PER_LONG)) {
|
|
addr = (unsigned long *)bitmap + BIT_WORD(bit);
|
|
if (*addr == ULONG_MAX) {
|
|
n += BITS_PER_LONG;
|
|
bit += BITS_PER_LONG;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (test_bit(bit, bitmap))
|
|
n++;
|
|
bit++;
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* Get a zone weight.
|
|
*/
|
|
static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone)
|
|
{
|
|
struct dmz_mblock *mblk;
|
|
sector_t chunk_block = 0;
|
|
unsigned int bit, nr_bits;
|
|
unsigned int nr_blocks = zmd->zone_nr_blocks;
|
|
void *bitmap;
|
|
int n = 0;
|
|
|
|
while (nr_blocks) {
|
|
/* Get bitmap block */
|
|
mblk = dmz_get_bitmap(zmd, zone, chunk_block);
|
|
if (IS_ERR(mblk)) {
|
|
n = 0;
|
|
break;
|
|
}
|
|
|
|
/* Count bits in this block */
|
|
bitmap = mblk->data;
|
|
bit = chunk_block & DMZ_BLOCK_MASK_BITS;
|
|
nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
|
|
n += dmz_count_bits(bitmap, bit, nr_bits);
|
|
|
|
dmz_release_mblock(zmd, mblk);
|
|
|
|
nr_blocks -= nr_bits;
|
|
chunk_block += nr_bits;
|
|
}
|
|
|
|
zone->weight = n;
|
|
}
|
|
|
|
/*
|
|
* Cleanup the zoned metadata resources.
|
|
*/
|
|
static void dmz_cleanup_metadata(struct dmz_metadata *zmd)
|
|
{
|
|
struct rb_root *root;
|
|
struct dmz_mblock *mblk, *next;
|
|
int i;
|
|
|
|
/* Release zone mapping resources */
|
|
if (zmd->map_mblk) {
|
|
for (i = 0; i < zmd->nr_map_blocks; i++)
|
|
dmz_release_mblock(zmd, zmd->map_mblk[i]);
|
|
kfree(zmd->map_mblk);
|
|
zmd->map_mblk = NULL;
|
|
}
|
|
|
|
/* Release super blocks */
|
|
for (i = 0; i < 2; i++) {
|
|
if (zmd->sb[i].mblk) {
|
|
dmz_free_mblock(zmd, zmd->sb[i].mblk);
|
|
zmd->sb[i].mblk = NULL;
|
|
}
|
|
}
|
|
|
|
/* Free cached blocks */
|
|
while (!list_empty(&zmd->mblk_dirty_list)) {
|
|
mblk = list_first_entry(&zmd->mblk_dirty_list,
|
|
struct dmz_mblock, link);
|
|
dmz_zmd_warn(zmd, "mblock %llu still in dirty list (ref %u)",
|
|
(u64)mblk->no, mblk->ref);
|
|
list_del_init(&mblk->link);
|
|
rb_erase(&mblk->node, &zmd->mblk_rbtree);
|
|
dmz_free_mblock(zmd, mblk);
|
|
}
|
|
|
|
while (!list_empty(&zmd->mblk_lru_list)) {
|
|
mblk = list_first_entry(&zmd->mblk_lru_list,
|
|
struct dmz_mblock, link);
|
|
list_del_init(&mblk->link);
|
|
rb_erase(&mblk->node, &zmd->mblk_rbtree);
|
|
dmz_free_mblock(zmd, mblk);
|
|
}
|
|
|
|
/* Sanity checks: the mblock rbtree should now be empty */
|
|
root = &zmd->mblk_rbtree;
|
|
rbtree_postorder_for_each_entry_safe(mblk, next, root, node) {
|
|
dmz_zmd_warn(zmd, "mblock %llu ref %u still in rbtree",
|
|
(u64)mblk->no, mblk->ref);
|
|
mblk->ref = 0;
|
|
dmz_free_mblock(zmd, mblk);
|
|
}
|
|
|
|
/* Free the zone descriptors */
|
|
dmz_drop_zones(zmd);
|
|
|
|
mutex_destroy(&zmd->mblk_flush_lock);
|
|
mutex_destroy(&zmd->map_lock);
|
|
}
|
|
|
|
static void dmz_print_dev(struct dmz_metadata *zmd, int num)
|
|
{
|
|
struct dmz_dev *dev = &zmd->dev[num];
|
|
|
|
if (bdev_zoned_model(dev->bdev) == BLK_ZONED_NONE)
|
|
dmz_dev_info(dev, "Regular block device");
|
|
else
|
|
dmz_dev_info(dev, "Host-%s zoned block device",
|
|
bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ?
|
|
"aware" : "managed");
|
|
if (zmd->sb_version > 1) {
|
|
sector_t sector_offset =
|
|
dev->zone_offset << zmd->zone_nr_sectors_shift;
|
|
|
|
dmz_dev_info(dev, " %llu 512-byte logical sectors (offset %llu)",
|
|
(u64)dev->capacity, (u64)sector_offset);
|
|
dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors (offset %llu)",
|
|
dev->nr_zones, (u64)zmd->zone_nr_sectors,
|
|
(u64)dev->zone_offset);
|
|
} else {
|
|
dmz_dev_info(dev, " %llu 512-byte logical sectors",
|
|
(u64)dev->capacity);
|
|
dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors",
|
|
dev->nr_zones, (u64)zmd->zone_nr_sectors);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize the zoned metadata.
|
|
*/
|
|
int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
|
|
struct dmz_metadata **metadata,
|
|
const char *devname)
|
|
{
|
|
struct dmz_metadata *zmd;
|
|
unsigned int i;
|
|
struct dm_zone *zone;
|
|
int ret;
|
|
|
|
zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL);
|
|
if (!zmd)
|
|
return -ENOMEM;
|
|
|
|
strcpy(zmd->devname, devname);
|
|
zmd->dev = dev;
|
|
zmd->nr_devs = num_dev;
|
|
zmd->mblk_rbtree = RB_ROOT;
|
|
init_rwsem(&zmd->mblk_sem);
|
|
mutex_init(&zmd->mblk_flush_lock);
|
|
spin_lock_init(&zmd->mblk_lock);
|
|
INIT_LIST_HEAD(&zmd->mblk_lru_list);
|
|
INIT_LIST_HEAD(&zmd->mblk_dirty_list);
|
|
|
|
mutex_init(&zmd->map_lock);
|
|
|
|
atomic_set(&zmd->unmap_nr_cache, 0);
|
|
INIT_LIST_HEAD(&zmd->unmap_cache_list);
|
|
INIT_LIST_HEAD(&zmd->map_cache_list);
|
|
|
|
atomic_set(&zmd->nr_reserved_seq_zones, 0);
|
|
INIT_LIST_HEAD(&zmd->reserved_seq_zones_list);
|
|
|
|
init_waitqueue_head(&zmd->free_wq);
|
|
|
|
/* Initialize zone descriptors */
|
|
ret = dmz_init_zones(zmd);
|
|
if (ret)
|
|
goto err;
|
|
|
|
/* Get super block */
|
|
ret = dmz_load_sb(zmd);
|
|
if (ret)
|
|
goto err;
|
|
|
|
/* Set metadata zones starting from sb_zone */
|
|
for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
|
|
zone = dmz_get(zmd, zmd->sb[0].zone->id + i);
|
|
if (!zone) {
|
|
dmz_zmd_err(zmd,
|
|
"metadata zone %u not present", i);
|
|
ret = -ENXIO;
|
|
goto err;
|
|
}
|
|
if (!dmz_is_rnd(zone) && !dmz_is_cache(zone)) {
|
|
dmz_zmd_err(zmd,
|
|
"metadata zone %d is not random", i);
|
|
ret = -ENXIO;
|
|
goto err;
|
|
}
|
|
set_bit(DMZ_META, &zone->flags);
|
|
}
|
|
/* Load mapping table */
|
|
ret = dmz_load_mapping(zmd);
|
|
if (ret)
|
|
goto err;
|
|
|
|
/*
|
|
* Cache size boundaries: allow at least 2 super blocks, the chunk map
|
|
* blocks and enough blocks to be able to cache the bitmap blocks of
|
|
* up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow
|
|
* the cache to add 512 more metadata blocks.
|
|
*/
|
|
zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16;
|
|
zmd->max_nr_mblks = zmd->min_nr_mblks + 512;
|
|
zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count;
|
|
zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan;
|
|
zmd->mblk_shrinker.seeks = DEFAULT_SEEKS;
|
|
|
|
/* Metadata cache shrinker */
|
|
ret = register_shrinker(&zmd->mblk_shrinker);
|
|
if (ret) {
|
|
dmz_zmd_err(zmd, "Register metadata cache shrinker failed");
|
|
goto err;
|
|
}
|
|
|
|
dmz_zmd_info(zmd, "DM-Zoned metadata version %d", zmd->sb_version);
|
|
for (i = 0; i < zmd->nr_devs; i++)
|
|
dmz_print_dev(zmd, i);
|
|
|
|
dmz_zmd_info(zmd, " %u zones of %llu 512-byte logical sectors",
|
|
zmd->nr_zones, (u64)zmd->zone_nr_sectors);
|
|
dmz_zmd_debug(zmd, " %u metadata zones",
|
|
zmd->nr_meta_zones * 2);
|
|
dmz_zmd_debug(zmd, " %u data zones for %u chunks",
|
|
zmd->nr_data_zones, zmd->nr_chunks);
|
|
dmz_zmd_debug(zmd, " %u cache zones (%u unmapped)",
|
|
zmd->nr_cache, atomic_read(&zmd->unmap_nr_cache));
|
|
for (i = 0; i < zmd->nr_devs; i++) {
|
|
dmz_zmd_debug(zmd, " %u random zones (%u unmapped)",
|
|
dmz_nr_rnd_zones(zmd, i),
|
|
dmz_nr_unmap_rnd_zones(zmd, i));
|
|
dmz_zmd_debug(zmd, " %u sequential zones (%u unmapped)",
|
|
dmz_nr_seq_zones(zmd, i),
|
|
dmz_nr_unmap_seq_zones(zmd, i));
|
|
}
|
|
dmz_zmd_debug(zmd, " %u reserved sequential data zones",
|
|
zmd->nr_reserved_seq);
|
|
dmz_zmd_debug(zmd, "Format:");
|
|
dmz_zmd_debug(zmd, "%u metadata blocks per set (%u max cache)",
|
|
zmd->nr_meta_blocks, zmd->max_nr_mblks);
|
|
dmz_zmd_debug(zmd, " %u data zone mapping blocks",
|
|
zmd->nr_map_blocks);
|
|
dmz_zmd_debug(zmd, " %u bitmap blocks",
|
|
zmd->nr_bitmap_blocks);
|
|
|
|
*metadata = zmd;
|
|
|
|
return 0;
|
|
err:
|
|
dmz_cleanup_metadata(zmd);
|
|
kfree(zmd);
|
|
*metadata = NULL;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Cleanup the zoned metadata resources.
|
|
*/
|
|
void dmz_dtr_metadata(struct dmz_metadata *zmd)
|
|
{
|
|
unregister_shrinker(&zmd->mblk_shrinker);
|
|
dmz_cleanup_metadata(zmd);
|
|
kfree(zmd);
|
|
}
|
|
|
|
/*
|
|
* Check zone information on resume.
|
|
*/
|
|
int dmz_resume_metadata(struct dmz_metadata *zmd)
|
|
{
|
|
struct dm_zone *zone;
|
|
sector_t wp_block;
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
/* Check zones */
|
|
for (i = 0; i < zmd->nr_zones; i++) {
|
|
zone = dmz_get(zmd, i);
|
|
if (!zone) {
|
|
dmz_zmd_err(zmd, "Unable to get zone %u", i);
|
|
return -EIO;
|
|
}
|
|
wp_block = zone->wp_block;
|
|
|
|
ret = dmz_update_zone(zmd, zone);
|
|
if (ret) {
|
|
dmz_zmd_err(zmd, "Broken zone %u", i);
|
|
return ret;
|
|
}
|
|
|
|
if (dmz_is_offline(zone)) {
|
|
dmz_zmd_warn(zmd, "Zone %u is offline", i);
|
|
continue;
|
|
}
|
|
|
|
/* Check write pointer */
|
|
if (!dmz_is_seq(zone))
|
|
zone->wp_block = 0;
|
|
else if (zone->wp_block != wp_block) {
|
|
dmz_zmd_err(zmd, "Zone %u: Invalid wp (%llu / %llu)",
|
|
i, (u64)zone->wp_block, (u64)wp_block);
|
|
zone->wp_block = wp_block;
|
|
dmz_invalidate_blocks(zmd, zone, zone->wp_block,
|
|
zmd->zone_nr_blocks - zone->wp_block);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|