[dm-devel] [PATCH 06/15] dm-zoned: temporary superblock for tertiary devices
Damien Le Moal
Damien.LeMoal at wdc.com
Thu May 28 02:54:17 UTC 2020
On 2020/05/27 15:22, Hannes Reinecke wrote:
> Checking the tertiary superblock just consists of validating UUIDs,
> crcs, and the generation number; it doesn't have contents which
> would be required during the actual operation.
> So we should be allocating a temporary superblock when checking
> tertiary devices and avoid having to store it together with the
> 'real' superblocks.
>
> Signed-off-by: Hannes Reinecke <hare at suse.de>
> ---
> drivers/md/dm-zoned-metadata.c | 104 ++++++++++++++++++++++-------------------
> 1 file changed, 57 insertions(+), 47 deletions(-)
>
> diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c
> index 839f9078806d..bb9ce72bf18c 100644
> --- a/drivers/md/dm-zoned-metadata.c
> +++ b/drivers/md/dm-zoned-metadata.c
> @@ -174,7 +174,7 @@ struct dmz_metadata {
> /* Zone information array */
> struct xarray zones;
>
> - struct dmz_sb sb[3];
> + struct dmz_sb sb[2];
> unsigned int mblk_primary;
> unsigned int sb_version;
> u64 sb_gen;
> @@ -1014,10 +1014,11 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
> /*
> * Check super block.
> */
> -static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
> +static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_sb *dsb,
> + bool tertiary)
> {
> - struct dmz_super *sb = zmd->sb[set].sb;
> - struct dmz_dev *dev = zmd->sb[set].dev;
> + 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;
> @@ -1034,7 +1035,7 @@ static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
> DMZ_META_VER, zmd->sb_version);
> return -EINVAL;
> }
> - if ((zmd->sb_version < 1) && (set == 2)) {
> + if ((zmd->sb_version < 1) && tertiary) {
You can remove the parentheses around zmd->sb_version < 1 here.
An shouldn't it be "zmd->sb_version <= 1" here ? That already was in the
previous round of updates and did not detect any problem though. Will check again.
> dmz_dev_err(dev, "Tertiary superblocks are not supported");
> return -EINVAL;
> }
> @@ -1078,7 +1079,7 @@ static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
> return -ENXIO;
> }
>
> - if (set == 2) {
> + if (tertiary) {
> /*
> * Generation number should be 0, but it doesn't
> * really matter if it isn't.
> @@ -1127,14 +1128,13 @@ static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
> /*
> * Read the first or second super block from disk.
> */
> -static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set)
> +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, zmd->sb[set].dev->name,
> - zmd->sb[set].block);
> + set, sb->dev->name, sb->block);
>
> - return dmz_rdwr_block(zmd->sb[set].dev, REQ_OP_READ,
> - zmd->sb[set].block, zmd->sb[set].mblk->page);
> + return dmz_rdwr_block(sb->dev, REQ_OP_READ,
> + sb->block, sb->mblk->page);
> }
>
> /*
> @@ -1162,7 +1162,7 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
> 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, 1) != 0)
> + if (dmz_read_sb(zmd, &zmd->sb[1], 1) != 0)
> break;
> if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
> return 0;
> @@ -1179,9 +1179,9 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
> }
>
> /*
> - * Read the first or second super block from disk.
> + * Read a super block from disk.
> */
> -static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set)
> +static int dmz_get_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set)
> {
> struct dmz_mblock *mblk;
> int ret;
> @@ -1191,14 +1191,14 @@ static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set)
> if (!mblk)
> return -ENOMEM;
>
> - zmd->sb[set].mblk = mblk;
> - zmd->sb[set].sb = mblk->data;
> + sb->mblk = mblk;
> + sb->sb = mblk->data;
>
> /* Read super block */
> - ret = dmz_read_sb(zmd, set);
> + ret = dmz_read_sb(zmd, sb, set);
> if (ret) {
> dmz_free_mblock(zmd, mblk);
> - zmd->sb[set].mblk = NULL;
> + sb->mblk = NULL;
> return ret;
> }
>
> @@ -1272,13 +1272,13 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
> /* Read and check the primary super block */
> zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
> zmd->sb[0].dev = dmz_zone_to_dev(zmd, zmd->sb[0].zone);
> - ret = dmz_get_sb(zmd, 0);
> + 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, 0);
> + ret = dmz_check_sb(zmd, &zmd->sb[0], false);
>
> /* Read and check secondary super block */
> if (ret == 0) {
> @@ -1291,7 +1291,7 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
> }
> 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, 1);
> + ret = dmz_get_sb(zmd, &zmd->sb[1], 1);
> } else
> ret = dmz_lookup_secondary_sb(zmd);
>
> @@ -1300,7 +1300,7 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
> return ret;
> }
>
> - ret = dmz_check_sb(zmd, 1);
> + ret = dmz_check_sb(zmd, &zmd->sb[1], false);
> if (ret == 0)
> sb_good[1] = true;
>
> @@ -1345,18 +1345,35 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
> "Using super block %u (gen %llu)",
> zmd->mblk_primary, zmd->sb_gen);
>
> - if ((zmd->sb_version > 1) && zmd->sb[2].zone) {
> - zmd->sb[2].block = dmz_start_block(zmd, zmd->sb[2].zone);
> - zmd->sb[2].dev = dmz_zone_to_dev(zmd, zmd->sb[2].zone);
> - ret = dmz_get_sb(zmd, 2);
> - if (ret) {
> - dmz_dev_err(zmd->sb[2].dev,
> - "Read tertiary super block failed");
> - return ret;
> + 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);
> + return -EINVAL;
Mem leaking sb here...
> + }
> + ret = dmz_get_sb(zmd, sb, i + 1);
> + if (ret) {
> + dmz_dev_err(sb->dev,
> + "Read tertiary super block failed");
> + return ret;
Here too.
> + }
> + ret = dmz_check_sb(zmd, sb, true);
> + dmz_free_mblock(zmd, sb->mblk);
> + if (ret == -EINVAL)
> + return ret;
And here.
> }
> - ret = dmz_check_sb(zmd, 2);
> - if (ret == -EINVAL)
> - return ret;
> + kfree(sb);
> }
> return 0;
> }
> @@ -1415,12 +1432,15 @@ static int dmz_init_zone(struct blk_zone *blkz, unsigned int num, void *data)
> zmd->sb[0].zone = zone;
> }
> }
> - if (zmd->nr_devs > 1 && !zmd->sb[2].zone) {
> - /* Tertiary superblock zone */
> - zmd->sb[2].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;
> }
>
> @@ -2858,16 +2878,6 @@ int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
> }
> set_bit(DMZ_META, &zone->flags);
> }
> - if (zmd->sb[2].zone) {
> - zone = dmz_get(zmd, zmd->sb[2].zone->id);
> - if (!zone) {
> - dmz_zmd_err(zmd,
> - "Tertiary metadata zone not present");
> - ret = -ENXIO;
> - goto err;
> - }
> - set_bit(DMZ_META, &zone->flags);
> - }
> /* Load mapping table */
> ret = dmz_load_mapping(zmd);
> if (ret)
>
--
Damien Le Moal
Western Digital Research
More information about the dm-devel
mailing list