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linux/drivers/md/dm-zoned-metadata.c
Christoph Hellwig c6bf3f0e25 block: use an on-stack bio in blkdev_issue_flush 
There is no point in allocating memory for a synchronous flush.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27 09:51:48 -07:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2017 Western Digital Corporation or its affiliates.
*
* This file is released under the GPL.
*/
#include "dm-zoned.h"
#include <linux/module.h>
#include <linux/crc32.h>
#include <linux/sched/mm.h>
#define DM_MSG_PREFIX "zoned metadata"
/*
* Metadata version.
*/
#define DMZ_META_VER 2
/*
* On-disk super block magic.
*/
#define DMZ_MAGIC ((((unsigned int)('D')) << 24) | \
(((unsigned int)('Z')) << 16) | \
(((unsigned int)('B')) << 8) | \
((unsigned int)('D')))
/*
* On disk super block.
* This uses only 512 B but uses on disk a full 4KB block. This block is
* followed on disk by the mapping table of chunks to zones and the bitmap
* blocks indicating zone block validity.
* The overall resulting metadata format is:
* (1) Super block (1 block)
* (2) Chunk mapping table (nr_map_blocks)
* (3) Bitmap blocks (nr_bitmap_blocks)
* All metadata blocks are stored in conventional zones, starting from
* the first conventional zone found on disk.
*/
struct dmz_super {
/* Magic number */
__le32 magic; /* 4 */
/* Metadata version number */
__le32 version; /* 8 */
/* Generation number */
__le64 gen; /* 16 */
/* This block number */
__le64 sb_block; /* 24 */
/* The number of metadata blocks, including this super block */
__le32 nr_meta_blocks; /* 28 */
/* The number of sequential zones reserved for reclaim */
__le32 nr_reserved_seq; /* 32 */
/* The number of entries in the mapping table */
__le32 nr_chunks; /* 36 */
/* The number of blocks used for the chunk mapping table */
__le32 nr_map_blocks; /* 40 */
/* The number of blocks used for the block bitmaps */
__le32 nr_bitmap_blocks; /* 44 */
/* Checksum */
__le32 crc; /* 48 */
/* DM-Zoned label */
u8 dmz_label[32]; /* 80 */
/* DM-Zoned UUID */
u8 dmz_uuid[16]; /* 96 */
/* Device UUID */
u8 dev_uuid[16]; /* 112 */
/* Padding to full 512B sector */
u8 reserved[400]; /* 512 */
};
/*
* Chunk mapping entry: entries are indexed by chunk number
* and give the zone ID (dzone_id) mapping the chunk on disk.
* This zone may be sequential or random. If it is a sequential
* zone, a second zone (bzone_id) used as a write buffer may
* also be specified. This second zone will always be a randomly
* writeable zone.
*/
struct dmz_map {
__le32 dzone_id;
__le32 bzone_id;
};
/*
* Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
*/
#define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
#define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES))
#define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1)
#define DMZ_MAP_UNMAPPED UINT_MAX
/*
* Meta data block descriptor (for cached metadata blocks).
*/
struct dmz_mblock {
struct rb_node node;
struct list_head link;
sector_t no;
unsigned int ref;
unsigned long state;
struct page *page;
void *data;
};
/*
* Metadata block state flags.
*/
enum {
DMZ_META_DIRTY,
DMZ_META_READING,
DMZ_META_WRITING,
DMZ_META_ERROR,
};
/*
* Super block information (one per metadata set).
*/
struct dmz_sb {
sector_t block;
struct dmz_dev *dev;
struct dmz_mblock *mblk;
struct dmz_super *sb;
struct dm_zone *zone;
};
/*
* In-memory metadata.
*/
struct dmz_metadata {
struct dmz_dev *dev;
unsigned int nr_devs;
char devname[BDEVNAME_SIZE];
char label[BDEVNAME_SIZE];
uuid_t uuid;
sector_t zone_bitmap_size;
unsigned int zone_nr_bitmap_blocks;
unsigned int zone_bits_per_mblk;
sector_t zone_nr_blocks;
sector_t zone_nr_blocks_shift;
sector_t zone_nr_sectors;
sector_t zone_nr_sectors_shift;
unsigned int nr_bitmap_blocks;
unsigned int nr_map_blocks;
unsigned int nr_zones;
unsigned int nr_useable_zones;
unsigned int nr_meta_blocks;
unsigned int nr_meta_zones;
unsigned int nr_data_zones;
unsigned int nr_cache_zones;
unsigned int nr_rnd_zones;
unsigned int nr_reserved_seq;
unsigned int nr_chunks;
/* Zone information array */
struct xarray zones;
struct dmz_sb sb[2];
unsigned int mblk_primary;
unsigned int sb_version;
u64 sb_gen;
unsigned int min_nr_mblks;
unsigned int max_nr_mblks;
atomic_t nr_mblks;
struct rw_semaphore mblk_sem;
struct mutex mblk_flush_lock;
spinlock_t mblk_lock;
struct rb_root mblk_rbtree;
struct list_head mblk_lru_list;
struct list_head mblk_dirty_list;
struct shrinker mblk_shrinker;
/* Zone allocation management */
struct mutex map_lock;
struct dmz_mblock **map_mblk;
unsigned int nr_cache;
atomic_t unmap_nr_cache;
struct list_head unmap_cache_list;
struct list_head map_cache_list;
atomic_t nr_reserved_seq_zones;
struct list_head reserved_seq_zones_list;
wait_queue_head_t free_wq;
};
#define dmz_zmd_info(zmd, format, args...) \
DMINFO("(%s): " format, (zmd)->label, ## args)
#define dmz_zmd_err(zmd, format, args...) \
DMERR("(%s): " format, (zmd)->label, ## args)
#define dmz_zmd_warn(zmd, format, args...) \
DMWARN("(%s): " format, (zmd)->label, ## args)
#define dmz_zmd_debug(zmd, format, args...) \
DMDEBUG("(%s): " format, (zmd)->label, ## args)
/*
* Various accessors
*/
static unsigned int dmz_dev_zone_id(struct dmz_metadata *zmd, struct dm_zone *zone)
{
if (WARN_ON(!zone))
return 0;
return zone->id - zone->dev->zone_offset;
}
sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
{
unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
return (sector_t)zone_id << zmd->zone_nr_sectors_shift;
}
sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
{
unsigned int zone_id = dmz_dev_zone_id(zmd, zone);
return (sector_t)zone_id << zmd->zone_nr_blocks_shift;
}
unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd)
{
return zmd->zone_nr_blocks;
}
unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd)
{
return zmd->zone_nr_blocks_shift;
}
unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd)
{
return zmd->zone_nr_sectors;
}
unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd)
{
return zmd->zone_nr_sectors_shift;
}
unsigned int dmz_nr_zones(struct dmz_metadata *zmd)
{
return zmd->nr_zones;
}
unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
{
return zmd->nr_chunks;
}
unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx)
{
return zmd->dev[idx].nr_rnd;
}
unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx)
{
return atomic_read(&zmd->dev[idx].unmap_nr_rnd);
}
unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd)
{
return zmd->nr_cache;
}
unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd)
{
return atomic_read(&zmd->unmap_nr_cache);
}
unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx)
{
return zmd->dev[idx].nr_seq;
}
unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx)
{
return atomic_read(&zmd->dev[idx].unmap_nr_seq);
}
static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
{
return xa_load(&zmd->zones, zone_id);
}
static struct dm_zone *dmz_insert(struct dmz_metadata *zmd,
unsigned int zone_id, struct dmz_dev *dev)
{
struct dm_zone *zone = kzalloc(sizeof(struct dm_zone), GFP_KERNEL);
if (!zone)
return ERR_PTR(-ENOMEM);
if (xa_insert(&zmd->zones, zone_id, zone, GFP_KERNEL)) {
kfree(zone);
return ERR_PTR(-EBUSY);
}
INIT_LIST_HEAD(&zone->link);
atomic_set(&zone->refcount, 0);
zone->id = zone_id;
zone->chunk = DMZ_MAP_UNMAPPED;
zone->dev = dev;
return zone;
}
const char *dmz_metadata_label(struct dmz_metadata *zmd)
{
return (const char *)zmd->label;
}
bool dmz_check_dev(struct dmz_metadata *zmd)
{
unsigned int i;
for (i = 0; i < zmd->nr_devs; i++) {
if (!dmz_check_bdev(&zmd->dev[i]))
return false;
}
return true;
}
bool dmz_dev_is_dying(struct dmz_metadata *zmd)
{
unsigned int i;
for (i = 0; i < zmd->nr_devs; i++) {
if (dmz_bdev_is_dying(&zmd->dev[i]))
return true;
}
return false;
}
/*
* Lock/unlock mapping table.
* The map lock also protects all the zone lists.
*/
void dmz_lock_map(struct dmz_metadata *zmd)
{
mutex_lock(&zmd->map_lock);
}
void dmz_unlock_map(struct dmz_metadata *zmd)
{
mutex_unlock(&zmd->map_lock);
}
/*
* Lock/unlock metadata access. This is a "read" lock on a semaphore
* that prevents metadata flush from running while metadata are being
* modified. The actual metadata write mutual exclusion is achieved with
* the map lock and zone state management (active and reclaim state are
* mutually exclusive).
*/
void dmz_lock_metadata(struct dmz_metadata *zmd)
{
down_read(&zmd->mblk_sem);
}
void dmz_unlock_metadata(struct dmz_metadata *zmd)
{
up_read(&zmd->mblk_sem);
}
/*
* Lock/unlock flush: prevent concurrent executions
* of dmz_flush_metadata as well as metadata modification in reclaim
* while flush is being executed.
*/
void dmz_lock_flush(struct dmz_metadata *zmd)
{
mutex_lock(&zmd->mblk_flush_lock);
}
void dmz_unlock_flush(struct dmz_metadata *zmd)
{
mutex_unlock(&zmd->mblk_flush_lock);
}
/*
* Allocate a metadata block.
*/
static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
sector_t mblk_no)
{
struct dmz_mblock *mblk = NULL;
/* See if we can reuse cached blocks */
if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
spin_lock(&zmd->mblk_lock);
mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
struct dmz_mblock, link);
if (mblk) {
list_del_init(&mblk->link);
rb_erase(&mblk->node, &zmd->mblk_rbtree);
mblk->no = mblk_no;
}
spin_unlock(&zmd->mblk_lock);
if (mblk)
return mblk;
}
/* Allocate a new block */
mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
if (!mblk)
return NULL;
mblk->page = alloc_page(GFP_NOIO);
if (!mblk->page) {
kfree(mblk);
return NULL;
}
RB_CLEAR_NODE(&mblk->node);
INIT_LIST_HEAD(&mblk->link);
mblk->ref = 0;
mblk->state = 0;
mblk->no = mblk_no;
mblk->data = page_address(mblk->page);
atomic_inc(&zmd->nr_mblks);
return mblk;
}
/*
* Free a metadata block.
*/
static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
{
__free_pages(mblk->page, 0);
kfree(mblk);
atomic_dec(&zmd->nr_mblks);
}
/*
* Insert a metadata block in the rbtree.
*/
static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
{
struct rb_root *root = &zmd->mblk_rbtree;
struct rb_node **new = &(root->rb_node), *parent = NULL;
struct dmz_mblock *b;
/* Figure out where to put the new node */
while (*new) {
b = container_of(*new, struct dmz_mblock, node);
parent = *new;
new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
}
/* Add new node and rebalance tree */
rb_link_node(&mblk->node, parent, new);
rb_insert_color(&mblk->node, root);
}
/*
* Lookup a metadata block in the rbtree. If the block is found, increment
* its reference count.
*/
static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd,
sector_t mblk_no)
{
struct rb_root *root = &zmd->mblk_rbtree;
struct rb_node *node = root->rb_node;
struct dmz_mblock *mblk;
while (node) {
mblk = container_of(node, struct dmz_mblock, node);
if (mblk->no == mblk_no) {
/*
* If this is the first reference to the block,
* remove it from the LRU list.
*/
mblk->ref++;
if (mblk->ref == 1 &&
!test_bit(DMZ_META_DIRTY, &mblk->state))
list_del_init(&mblk->link);
return mblk;
}
node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
}
return NULL;
}
/*
* Metadata block BIO end callback.
*/
static void dmz_mblock_bio_end_io(struct bio *bio)
{
struct dmz_mblock *mblk = bio->bi_private;
int flag;
if (bio->bi_status)
set_bit(DMZ_META_ERROR, &mblk->state);
if (bio_op(bio) == REQ_OP_WRITE)
flag = DMZ_META_WRITING;
else
flag = DMZ_META_READING;
clear_bit_unlock(flag, &mblk->state);
smp_mb__after_atomic();
wake_up_bit(&mblk->state, flag);
bio_put(bio);
}
/*
* 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(GFP_NOIO, 1);
if (!bio) {
dmz_free_mblock(zmd, mblk);
return ERR_PTR(-ENOMEM);
}
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_set_dev(bio, dev->bdev);
bio->bi_private = mblk;
bio->bi_end_io = dmz_mblock_bio_end_io;
bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
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(GFP_NOIO, 1);
if (!bio) {
set_bit(DMZ_META_ERROR, &mblk->state);
return -ENOMEM;
}
set_bit(DMZ_META_WRITING, &mblk->state);
bio->bi_iter.bi_sector = dmz_blk2sect(block);
bio_set_dev(bio, dev->bdev);
bio->bi_private = mblk;
bio->bi_end_io = dmz_mblock_bio_end_io;
bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
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(GFP_NOIO, 1);
if (!bio)
return -ENOMEM;
bio->bi_iter.bi_sector = dmz_blk2sect(block);
bio_set_dev(bio, dev->bdev);
bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
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 %s block %llu",
set, sb->dev->name, 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;
}
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;
}
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