bcache: Track dirty data by stripe
To make background writeback aware of raid5/6 stripes, we first need to
track the amount of dirty data within each stripe - we do this by
breaking up the existing sectors_dirty into per stripe atomic_ts
Signed-off-by: Kent Overstreet <koverstreet@google.com>
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index dbfa1c3..8c73f0c 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -10,6 +10,7 @@
#include "btree.h"
#include "debug.h"
#include "request.h"
+#include "writeback.h"
#include <linux/blkdev.h>
#include <linux/buffer_head.h>
@@ -744,13 +745,35 @@
mempool_destroy(d->unaligned_bvec);
if (d->bio_split)
bioset_free(d->bio_split);
+ if (is_vmalloc_addr(d->stripe_sectors_dirty))
+ vfree(d->stripe_sectors_dirty);
+ else
+ kfree(d->stripe_sectors_dirty);
closure_debug_destroy(&d->cl);
}
-static int bcache_device_init(struct bcache_device *d, unsigned block_size)
+static int bcache_device_init(struct bcache_device *d, unsigned block_size,
+ sector_t sectors)
{
struct request_queue *q;
+ size_t n;
+
+ if (!d->stripe_size_bits)
+ d->stripe_size_bits = 31;
+
+ d->nr_stripes = round_up(sectors, 1 << d->stripe_size_bits) >>
+ d->stripe_size_bits;
+
+ if (!d->nr_stripes || d->nr_stripes > SIZE_MAX / sizeof(atomic_t))
+ return -ENOMEM;
+
+ n = d->nr_stripes * sizeof(atomic_t);
+ d->stripe_sectors_dirty = n < PAGE_SIZE << 6
+ ? kzalloc(n, GFP_KERNEL)
+ : vzalloc(n);
+ if (!d->stripe_sectors_dirty)
+ return -ENOMEM;
if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
!(d->unaligned_bvec = mempool_create_kmalloc_pool(1,
@@ -760,6 +783,7 @@
!(q = blk_alloc_queue(GFP_KERNEL)))
return -ENOMEM;
+ set_capacity(d->disk, sectors);
snprintf(d->disk->disk_name, DISK_NAME_LEN, "bcache%i", bcache_minor);
d->disk->major = bcache_major;
@@ -1047,7 +1071,8 @@
hlist_add_head(&io->hash, dc->io_hash + RECENT_IO);
}
- ret = bcache_device_init(&dc->disk, block_size);
+ ret = bcache_device_init(&dc->disk, block_size,
+ dc->bdev->bd_part->nr_sects - dc->sb.data_offset);
if (ret)
return ret;
@@ -1146,11 +1171,10 @@
kobject_init(&d->kobj, &bch_flash_dev_ktype);
- if (bcache_device_init(d, block_bytes(c)))
+ if (bcache_device_init(d, block_bytes(c), u->sectors))
goto err;
bcache_device_attach(d, c, u - c->uuids);
- set_capacity(d->disk, u->sectors);
bch_flash_dev_request_init(d);
add_disk(d->disk);