Mailing List Archive

[PATCH 38/45] block: switch partition lookup to use struct block_device
Use struct block_device to lookup partitions on a disk. This removes
all usage of struct hd_struct from the I/O path, and this allows removing
the percpu refcount in struct hd_struct.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
block/bio.c | 4 +-
block/blk-core.c | 66 ++++++++++++++----------------
block/blk-flush.c | 2 +-
block/blk-mq.c | 9 ++--
block/blk-mq.h | 7 ++--
block/blk.h | 4 +-
block/genhd.c | 56 +++++++++++++------------
block/partitions/core.c | 7 +---
drivers/block/drbd/drbd_receiver.c | 2 +-
drivers/block/drbd/drbd_worker.c | 2 +-
drivers/block/zram/zram_drv.c | 2 +-
drivers/md/bcache/request.c | 4 +-
drivers/md/dm.c | 4 +-
drivers/md/md.c | 4 +-
drivers/nvme/target/admin-cmd.c | 20 ++++-----
fs/ext4/super.c | 18 +++-----
fs/ext4/sysfs.c | 10 +----
fs/f2fs/f2fs.h | 2 +-
fs/f2fs/super.c | 6 +--
include/linux/blkdev.h | 8 ++--
include/linux/genhd.h | 4 +-
include/linux/part_stat.h | 17 ++++----
22 files changed, 120 insertions(+), 138 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index 669bb47a31988e..ebb18136b86f2f 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -608,12 +608,12 @@ void bio_truncate(struct bio *bio, unsigned new_size)
void guard_bio_eod(struct bio *bio)
{
sector_t maxsector;
- struct hd_struct *part;
+ struct block_device *part;

rcu_read_lock();
part = __disk_get_part(bio->bi_disk, bio->bi_partno);
if (part)
- maxsector = bdev_nr_sectors(part->bdev);
+ maxsector = bdev_nr_sectors(part);
else
maxsector = get_capacity(bio->bi_disk);
rcu_read_unlock();
diff --git a/block/blk-core.c b/block/blk-core.c
index 9ea70275fc1cfe..cee568389b7e11 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -666,10 +666,9 @@ static int __init setup_fail_make_request(char *str)
}
__setup("fail_make_request=", setup_fail_make_request);

-static bool should_fail_request(struct hd_struct *part, unsigned int bytes)
+static bool should_fail_request(struct block_device *part, unsigned int bytes)
{
- return part->bdev->bd_make_it_fail &&
- should_fail(&fail_make_request, bytes);
+ return part->bd_make_it_fail && should_fail(&fail_make_request, bytes);
}

static int __init fail_make_request_debugfs(void)
@@ -684,7 +683,7 @@ late_initcall(fail_make_request_debugfs);

#else /* CONFIG_FAIL_MAKE_REQUEST */

-static inline bool should_fail_request(struct hd_struct *part,
+static inline bool should_fail_request(struct block_device *part,
unsigned int bytes)
{
return false;
@@ -692,11 +691,11 @@ static inline bool should_fail_request(struct hd_struct *part,

#endif /* CONFIG_FAIL_MAKE_REQUEST */

-static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)
+static inline bool bio_check_ro(struct bio *bio, struct block_device *part)
{
const int op = bio_op(bio);

- if (part->bdev->bd_read_only && op_is_write(op)) {
+ if (part->bd_read_only && op_is_write(op)) {
char b[BDEVNAME_SIZE];

if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
@@ -704,7 +703,7 @@ static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)

WARN_ONCE(1,
"Trying to write to read-only block-device %s (partno %d)\n",
- bio_devname(bio, b), part->partno);
+ bio_devname(bio, b), part->bd_partno);
/* Older lvm-tools actually trigger this */
return false;
}
@@ -714,8 +713,7 @@ static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)

static noinline int should_fail_bio(struct bio *bio)
{
- if (should_fail_request(bio->bi_disk->part0->bd_part,
- bio->bi_iter.bi_size))
+ if (should_fail_request(bio->bi_disk->part0, bio->bi_iter.bi_size))
return -EIO;
return 0;
}
@@ -744,7 +742,7 @@ static inline int bio_check_eod(struct bio *bio, sector_t maxsector)
*/
static inline int blk_partition_remap(struct bio *bio)
{
- struct hd_struct *p;
+ struct block_device *p;
int ret = -EIO;

rcu_read_lock();
@@ -757,12 +755,12 @@ static inline int blk_partition_remap(struct bio *bio)
goto out;

if (bio_sectors(bio)) {
- if (bio_check_eod(bio, bdev_nr_sectors(p->bdev)))
+ if (bio_check_eod(bio, bdev_nr_sectors(p)))
goto out;
- bio->bi_iter.bi_sector += p->bdev->bd_start_sect;
- trace_block_bio_remap(bio->bi_disk->queue, bio, part_devt(p),
+ bio->bi_iter.bi_sector += p->bd_start_sect;
+ trace_block_bio_remap(bio->bi_disk->queue, bio, p->bd_dev,
bio->bi_iter.bi_sector -
- p->bdev->bd_start_sect);
+ p->bd_start_sect);
}
bio->bi_partno = 0;
ret = 0;
@@ -832,7 +830,7 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio)
if (unlikely(blk_partition_remap(bio)))
goto end_io;
} else {
- if (unlikely(bio_check_ro(bio, bio->bi_disk->part0->bd_part)))
+ if (unlikely(bio_check_ro(bio, bio->bi_disk->part0)))
goto end_io;
if (unlikely(bio_check_eod(bio, get_capacity(bio->bi_disk))))
goto end_io;
@@ -1204,7 +1202,7 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *
return ret;

if (rq->rq_disk &&
- should_fail_request(rq->rq_disk->part0->bd_part, blk_rq_bytes(rq)))
+ should_fail_request(rq->rq_disk->part0, blk_rq_bytes(rq)))
return BLK_STS_IOERR;

if (blk_crypto_insert_cloned_request(rq))
@@ -1263,17 +1261,18 @@ unsigned int blk_rq_err_bytes(const struct request *rq)
}
EXPORT_SYMBOL_GPL(blk_rq_err_bytes);

-static void update_io_ticks(struct hd_struct *part, unsigned long now, bool end)
+static void update_io_ticks(struct block_device *part, unsigned long now,
+ bool end)
{
unsigned long stamp;
again:
- stamp = READ_ONCE(part->bdev->bd_stamp);
+ stamp = READ_ONCE(part->bd_stamp);
if (unlikely(stamp != now)) {
- if (likely(cmpxchg(&part->bdev->bd_stamp, stamp, now) == stamp))
+ if (likely(cmpxchg(&part->bd_stamp, stamp, now) == stamp))
__part_stat_add(part, io_ticks, end ? now - stamp : 1);
}
- if (part->partno) {
- part = part_to_disk(part)->part0->bd_part;
+ if (part->bd_partno) {
+ part = bdev_whole(part);
goto again;
}
}
@@ -1282,11 +1281,9 @@ static void blk_account_io_completion(struct request *req, unsigned int bytes)
{
if (req->part && blk_do_io_stat(req)) {
const int sgrp = op_stat_group(req_op(req));
- struct hd_struct *part;

part_stat_lock();
- part = req->part;
- part_stat_add(part, sectors[sgrp], bytes >> 9);
+ part_stat_add(req->part, sectors[sgrp], bytes >> 9);
part_stat_unlock();
}
}
@@ -1301,14 +1298,11 @@ void blk_account_io_done(struct request *req, u64 now)
if (req->part && blk_do_io_stat(req) &&
!(req->rq_flags & RQF_FLUSH_SEQ)) {
const int sgrp = op_stat_group(req_op(req));
- struct hd_struct *part;

part_stat_lock();
- part = req->part;
-
- update_io_ticks(part, jiffies, true);
- part_stat_inc(part, ios[sgrp]);
- part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
+ update_io_ticks(req->part, jiffies, true);
+ part_stat_inc(req->part, ios[sgrp]);
+ part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns);
part_stat_unlock();
}
}
@@ -1325,7 +1319,7 @@ void blk_account_io_start(struct request *rq)
part_stat_unlock();
}

-static unsigned long __part_start_io_acct(struct hd_struct *part,
+static unsigned long __part_start_io_acct(struct block_device *part,
unsigned int sectors, unsigned int op)
{
const int sgrp = op_stat_group(op);
@@ -1341,7 +1335,7 @@ static unsigned long __part_start_io_acct(struct hd_struct *part,
return now;
}

-unsigned long part_start_io_acct(struct gendisk *disk, struct hd_struct **part,
+unsigned long part_start_io_acct(struct gendisk *disk, struct block_device **part,
struct bio *bio)
{
*part = disk_map_sector_rcu(disk, bio->bi_iter.bi_sector);
@@ -1353,11 +1347,11 @@ EXPORT_SYMBOL_GPL(part_start_io_acct);
unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
unsigned int op)
{
- return __part_start_io_acct(disk->part0->bd_part, sectors, op);
+ return __part_start_io_acct(disk->part0, sectors, op);
}
EXPORT_SYMBOL(disk_start_io_acct);

-static void __part_end_io_acct(struct hd_struct *part, unsigned int op,
+static void __part_end_io_acct(struct block_device *part, unsigned int op,
unsigned long start_time)
{
const int sgrp = op_stat_group(op);
@@ -1371,7 +1365,7 @@ static void __part_end_io_acct(struct hd_struct *part, unsigned int op,
part_stat_unlock();
}

-void part_end_io_acct(struct hd_struct *part, struct bio *bio,
+void part_end_io_acct(struct block_device *part, struct bio *bio,
unsigned long start_time)
{
__part_end_io_acct(part, bio_op(bio), start_time);
@@ -1381,7 +1375,7 @@ EXPORT_SYMBOL_GPL(part_end_io_acct);
void disk_end_io_acct(struct gendisk *disk, unsigned int op,
unsigned long start_time)
{
- __part_end_io_acct(disk->part0->bd_part, op, start_time);
+ __part_end_io_acct(disk->part0, op, start_time);
}
EXPORT_SYMBOL(disk_end_io_acct);

diff --git a/block/blk-flush.c b/block/blk-flush.c
index fcd0a60574dff8..9507dcdd58814c 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -139,7 +139,7 @@ static void blk_flush_queue_rq(struct request *rq, bool add_front)

static void blk_account_io_flush(struct request *rq)
{
- struct hd_struct *part = rq->rq_disk->part0->bd_part;
+ struct block_device *part = rq->rq_disk->part0;

part_stat_lock();
part_stat_inc(part, ios[STAT_FLUSH]);
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 55bcee5dc0320c..a2593748fa5342 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -95,7 +95,7 @@ static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx,
}

struct mq_inflight {
- struct hd_struct *part;
+ struct block_device *part;
unsigned int inflight[2];
};

@@ -111,7 +111,8 @@ static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
return true;
}

-unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
+unsigned int blk_mq_in_flight(struct request_queue *q,
+ struct block_device *part)
{
struct mq_inflight mi = { .part = part };

@@ -120,8 +121,8 @@ unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
return mi.inflight[0] + mi.inflight[1];
}

-void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
- unsigned int inflight[2])
+void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
+ unsigned int inflight[2])
{
struct mq_inflight mi = { .part = part };

diff --git a/block/blk-mq.h b/block/blk-mq.h
index a52703c98b7736..c696515766c780 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -182,9 +182,10 @@ static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
return hctx->nr_ctx && hctx->tags;
}

-unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
-void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
- unsigned int inflight[2]);
+unsigned int blk_mq_in_flight(struct request_queue *q,
+ struct block_device *part);
+void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
+ unsigned int inflight[2]);

static inline void blk_mq_put_dispatch_budget(struct request_queue *q)
{
diff --git a/block/blk.h b/block/blk.h
index 32ac41f7557fcc..d5bf8f3a078186 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -215,7 +215,7 @@ static inline void elevator_exit(struct request_queue *q,
__elevator_exit(q, e);
}

-struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
+struct block_device *__disk_get_part(struct gendisk *disk, int partno);

ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
char *buf);
@@ -348,7 +348,7 @@ void blk_queue_free_zone_bitmaps(struct request_queue *q);
static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
#endif

-struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
+struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);

int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
void blk_free_devt(dev_t devt);
diff --git a/block/genhd.c b/block/genhd.c
index 3bbf6d3a69ec63..197120c0c60f23 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -116,7 +116,7 @@ static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat)
}
}

-static unsigned int part_in_flight(struct hd_struct *part)
+static unsigned int part_in_flight(struct block_device *part)
{
unsigned int inflight = 0;
int cpu;
@@ -131,7 +131,8 @@ static unsigned int part_in_flight(struct hd_struct *part)
return inflight;
}

-static void part_in_flight_rw(struct hd_struct *part, unsigned int inflight[2])
+static void part_in_flight_rw(struct block_device *part,
+ unsigned int inflight[2])
{
int cpu;

@@ -147,7 +148,7 @@ static void part_in_flight_rw(struct hd_struct *part, unsigned int inflight[2])
inflight[1] = 0;
}

-struct hd_struct *__disk_get_part(struct gendisk *disk, int partno)
+struct block_device *__disk_get_part(struct gendisk *disk, int partno)
{
struct disk_part_tbl *ptbl = rcu_dereference(disk->part_tbl);

@@ -172,15 +173,18 @@ struct hd_struct *__disk_get_part(struct gendisk *disk, int partno)
*/
struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
{
- struct hd_struct *part;
+ struct block_device *part;

rcu_read_lock();
part = __disk_get_part(disk, partno);
- if (part)
- get_device(part_to_dev(part));
- rcu_read_unlock();
+ if (!part) {
+ rcu_read_unlock();
+ return NULL;
+ }

- return part;
+ get_device(part_to_dev(part->bd_part));
+ rcu_read_unlock();
+ return part->bd_part;
}

/**
@@ -254,19 +258,19 @@ struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)

/* iterate to the next partition */
for (; piter->idx != end; piter->idx += inc) {
- struct hd_struct *part;
+ struct block_device *part;

part = rcu_dereference(ptbl->part[piter->idx]);
if (!part)
continue;
- if (!bdev_nr_sectors(part->bdev) &&
+ if (!bdev_nr_sectors(part) &&
!(piter->flags & DISK_PITER_INCL_EMPTY) &&
!(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
piter->idx == 0))
continue;

- get_device(part_to_dev(part));
- piter->part = part;
+ get_device(part_to_dev(part->bd_part));
+ piter->part = part->bd_part;
piter->idx += inc;
break;
}
@@ -293,10 +297,10 @@ void disk_part_iter_exit(struct disk_part_iter *piter)
}
EXPORT_SYMBOL_GPL(disk_part_iter_exit);

-static inline int sector_in_part(struct hd_struct *part, sector_t sector)
+static inline int sector_in_part(struct block_device *part, sector_t sector)
{
- return part->bdev->bd_start_sect <= sector &&
- sector < part->bdev->bd_start_sect + bdev_nr_sectors(part->bdev);
+ return part->bd_start_sect <= sector &&
+ sector < part->bd_start_sect + bdev_nr_sectors(part);
}

/**
@@ -314,10 +318,10 @@ static inline int sector_in_part(struct hd_struct *part, sector_t sector)
* Found partition on success, part0 is returned if no partition matches
* or the matched partition is being deleted.
*/
-struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
+struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
{
struct disk_part_tbl *ptbl;
- struct hd_struct *part;
+ struct block_device *part;
int i;

rcu_read_lock();
@@ -336,7 +340,7 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
}
}

- part = disk->part0->bd_part;
+ part = disk->part0;
out_unlock:
rcu_read_unlock();
return part;
@@ -866,7 +870,7 @@ void del_gendisk(struct gendisk *disk)
kobject_put(disk->part0->bd_holder_dir);
kobject_put(disk->slave_dir);

- part_stat_set_all(disk->part0->bd_part, 0);
+ part_stat_set_all(disk->part0, 0);
disk->part0->bd_stamp = 0;
if (!sysfs_deprecated)
sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
@@ -1173,9 +1177,9 @@ ssize_t part_stat_show(struct device *dev,

part_stat_read_all(p, &stat);
if (queue_is_mq(q))
- inflight = blk_mq_in_flight(q, p);
+ inflight = blk_mq_in_flight(q, p->bdev);
else
- inflight = part_in_flight(p);
+ inflight = part_in_flight(p->bdev);

return sprintf(buf,
"%8lu %8lu %8llu %8u "
@@ -1215,9 +1219,9 @@ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
unsigned int inflight[2];

if (queue_is_mq(q))
- blk_mq_in_flight_rw(q, p, inflight);
+ blk_mq_in_flight_rw(q, p->bdev, inflight);
else
- part_in_flight_rw(p, inflight);
+ part_in_flight_rw(p->bdev, inflight);

return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
}
@@ -1490,9 +1494,9 @@ static int diskstats_show(struct seq_file *seqf, void *v)
while ((hd = disk_part_iter_next(&piter))) {
part_stat_read_all(hd, &stat);
if (queue_is_mq(gp->queue))
- inflight = blk_mq_in_flight(gp->queue, hd);
+ inflight = blk_mq_in_flight(gp->queue, hd->bdev);
else
- inflight = part_in_flight(hd);
+ inflight = part_in_flight(hd->bdev);

seq_printf(seqf, "%4d %7d %s "
"%lu %lu %lu %u "
@@ -1610,7 +1614,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id)
goto out_bdput;

ptbl = rcu_dereference_protected(disk->part_tbl, 1);
- rcu_assign_pointer(ptbl->part[0], disk->part0->bd_part);
+ rcu_assign_pointer(ptbl->part[0], disk->part0);

disk->minors = minors;
rand_initialize_disk(disk);
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 4b0352cb29e132..8beab9e7727e27 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -298,12 +298,9 @@ void delete_partition(struct hd_struct *part)
struct disk_part_tbl *ptbl =
rcu_dereference_protected(disk->part_tbl, 1);

- /*
- * ->part_tbl is referenced in this part's release handler, so
- * we have to hold the disk device
- */
rcu_assign_pointer(ptbl->part[part->partno], NULL);
rcu_assign_pointer(ptbl->last_lookup, NULL);
+
kobject_put(part->bdev->bd_holder_dir);
device_del(part_to_dev(part));

@@ -421,7 +418,7 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno,

/* everything is up and running, commence */
bdev_add(bdev, devt);
- rcu_assign_pointer(ptbl->part[partno], p);
+ rcu_assign_pointer(ptbl->part[partno], bdev);

/* suppress uevent if the disk suppresses it */
if (!dev_get_uevent_suppress(ddev))
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 9e5c2fdfda3629..09c86ef3f0fd93 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -2802,7 +2802,7 @@ bool drbd_rs_c_min_rate_throttle(struct drbd_device *device)
if (c_min_rate == 0)
return false;

- curr_events = (int)part_stat_read_accum(disk->part0->bd_part, sectors) -
+ curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
atomic_read(&device->rs_sect_ev);

if (atomic_read(&device->ap_actlog_cnt)
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 343f56b86bb766..02044ab7f767d5 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1679,7 +1679,7 @@ void drbd_rs_controller_reset(struct drbd_device *device)
atomic_set(&device->rs_sect_ev, 0);
device->rs_in_flight = 0;
device->rs_last_events =
- (int)part_stat_read_accum(disk->part0->bd_part, sectors);
+ (int)part_stat_read_accum(disk->part0, sectors);

/* Updating the RCU protected object in place is necessary since
this function gets called from atomic context.
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 153858734cd47d..01757f9578dcb8 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1687,7 +1687,7 @@ static void zram_reset_device(struct zram *zram)
zram->disksize = 0;

set_capacity_and_notify(zram->disk, 0);
- part_stat_set_all(zram->disk->part0->bd_part, 0);
+ part_stat_set_all(zram->disk->part0, 0);

up_write(&zram->init_lock);
/* I/O operation under all of CPU are done so let's free */
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index afac8d07c1bd00..85b1f2a9b72d68 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -475,7 +475,7 @@ struct search {
unsigned int read_dirty_data:1;
unsigned int cache_missed:1;

- struct hd_struct *part;
+ struct block_device *part;
unsigned long start_time;

struct btree_op op;
@@ -1073,7 +1073,7 @@ struct detached_dev_io_private {
unsigned long start_time;
bio_end_io_t *bi_end_io;
void *bi_private;
- struct hd_struct *part;
+ struct block_device *part;
};

static void detached_dev_end_io(struct bio *bio)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 1b2db4d530ea71..176adcff56b380 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1607,7 +1607,7 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
* (by eliminating DM's splitting and just using bio_split)
*/
part_stat_lock();
- __dm_part_stat_sub(dm_disk(md)->part0->bd_part,
+ __dm_part_stat_sub(dm_disk(md)->part0,
sectors[op_stat_group(bio_op(bio))], ci.sector_count);
part_stat_unlock();

@@ -2242,7 +2242,7 @@ EXPORT_SYMBOL_GPL(dm_put);
static bool md_in_flight_bios(struct mapped_device *md)
{
int cpu;
- struct hd_struct *part = dm_disk(md)->part0->bd_part;
+ struct block_device *part = dm_disk(md)->part0;
long sum = 0;

for_each_possible_cpu(cpu) {
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3696c2d77a4dd7..0065736f05b428 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -464,7 +464,7 @@ struct md_io {
bio_end_io_t *orig_bi_end_io;
void *orig_bi_private;
unsigned long start_time;
- struct hd_struct *part;
+ struct block_device *part;
};

static void md_end_io(struct bio *bio)
@@ -8441,7 +8441,7 @@ static int is_mddev_idle(struct mddev *mddev, int init)
rcu_read_lock();
rdev_for_each_rcu(rdev, mddev) {
struct gendisk *disk = rdev->bdev->bd_disk;
- curr_events = (int)part_stat_read_accum(disk->part0->bd_part, sectors) -
+ curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
atomic_read(&disk->sync_io);
/* sync IO will cause sync_io to increase before the disk_stats
* as sync_io is counted when a request starts, and
diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index dca34489a1dc9e..8d90235e4fcc5a 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -89,12 +89,12 @@ static u16 nvmet_get_smart_log_nsid(struct nvmet_req *req,
if (!ns->bdev)
goto out;

- host_reads = part_stat_read(ns->bdev->bd_part, ios[READ]);
- data_units_read = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
- sectors[READ]), 1000);
- host_writes = part_stat_read(ns->bdev->bd_part, ios[WRITE]);
- data_units_written = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
- sectors[WRITE]), 1000);
+ host_reads = part_stat_read(ns->bdev, ios[READ]);
+ data_units_read =
+ DIV_ROUND_UP(part_stat_read(ns->bdev, sectors[READ]), 1000);
+ host_writes = part_stat_read(ns->bdev, ios[WRITE]);
+ data_units_written =
+ DIV_ROUND_UP(part_stat_read(ns->bdev, sectors[WRITE]), 1000);

put_unaligned_le64(host_reads, &slog->host_reads[0]);
put_unaligned_le64(data_units_read, &slog->data_units_read[0]);
@@ -120,12 +120,12 @@ static u16 nvmet_get_smart_log_all(struct nvmet_req *req,
/* we don't have the right data for file backed ns */
if (!ns->bdev)
continue;
- host_reads += part_stat_read(ns->bdev->bd_part, ios[READ]);
+ host_reads += part_stat_read(ns->bdev, ios[READ]);
data_units_read += DIV_ROUND_UP(
- part_stat_read(ns->bdev->bd_part, sectors[READ]), 1000);
- host_writes += part_stat_read(ns->bdev->bd_part, ios[WRITE]);
+ part_stat_read(ns->bdev, sectors[READ]), 1000);
+ host_writes += part_stat_read(ns->bdev, ios[WRITE]);
data_units_written += DIV_ROUND_UP(
- part_stat_read(ns->bdev->bd_part, sectors[WRITE]), 1000);
+ part_stat_read(ns->bdev, sectors[WRITE]), 1000);
}

put_unaligned_le64(host_reads, &slog->host_reads[0]);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 6633b20224d509..c303a0ff0b1701 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4048,9 +4048,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
sbi->s_sb = sb;
sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
sbi->s_sb_block = sb_block;
- if (sb->s_bdev->bd_part)
- sbi->s_sectors_written_start =
- part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
+ sbi->s_sectors_written_start =
+ part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);

/* Cleanup superblock name */
strreplace(sb->s_id, '/', '!');
@@ -5509,15 +5508,10 @@ static int ext4_commit_super(struct super_block *sb, int sync)
*/
if (!(sb->s_flags & SB_RDONLY))
ext4_update_tstamp(es, s_wtime);
- if (sb->s_bdev->bd_part)
- es->s_kbytes_written =
- cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
- ((part_stat_read(sb->s_bdev->bd_part,
- sectors[STAT_WRITE]) -
- EXT4_SB(sb)->s_sectors_written_start) >> 1));
- else
- es->s_kbytes_written =
- cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
+ es->s_kbytes_written =
+ cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
+ ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
+ EXT4_SB(sb)->s_sectors_written_start) >> 1));
if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
ext4_free_blocks_count_set(es,
EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 4e27fe6ed3ae6a..075aa3a19ff5f1 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -62,11 +62,8 @@ static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;

- if (!sb->s_bdev->bd_part)
- return snprintf(buf, PAGE_SIZE, "0\n");
return snprintf(buf, PAGE_SIZE, "%lu\n",
- (part_stat_read(sb->s_bdev->bd_part,
- sectors[STAT_WRITE]) -
+ (part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
sbi->s_sectors_written_start) >> 1);
}

@@ -74,12 +71,9 @@ static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;

- if (!sb->s_bdev->bd_part)
- return snprintf(buf, PAGE_SIZE, "0\n");
return snprintf(buf, PAGE_SIZE, "%llu\n",
(unsigned long long)(sbi->s_kbytes_written +
- ((part_stat_read(sb->s_bdev->bd_part,
- sectors[STAT_WRITE]) -
+ ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
EXT4_SB(sb)->s_sectors_written_start) >> 1)));
}

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index cb700d79729680..49681a8d2b14a5 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1675,7 +1675,7 @@ static inline bool f2fs_is_multi_device(struct f2fs_sb_info *sbi)
* and the return value is in kbytes. s is of struct f2fs_sb_info.
*/
#define BD_PART_WRITTEN(s) \
-(((u64)part_stat_read((s)->sb->s_bdev->bd_part, sectors[STAT_WRITE]) - \
+ (((u64)part_stat_read((s)->sb->s_bdev, sectors[STAT_WRITE]) - \
(s)->sectors_written_start) >> 1)

static inline void f2fs_update_time(struct f2fs_sb_info *sbi, int type)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index d4e7fab352bacb..af9f449da64bac 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3700,10 +3700,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
}

/* For write statistics */
- if (sb->s_bdev->bd_part)
- sbi->sectors_written_start =
- (u64)part_stat_read(sb->s_bdev->bd_part,
- sectors[STAT_WRITE]);
+ sbi->sectors_written_start =
+ (u64)part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);

/* Read accumulated write IO statistics if exists */
seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8fc0b266610f7f..0e83989b9678c3 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -191,7 +191,7 @@ struct request {
};

struct gendisk *rq_disk;
- struct hd_struct *part;
+ struct block_device *part;
#ifdef CONFIG_BLK_RQ_ALLOC_TIME
/* Time that the first bio started allocating this request. */
u64 alloc_time_ns;
@@ -1943,9 +1943,9 @@ unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
void disk_end_io_acct(struct gendisk *disk, unsigned int op,
unsigned long start_time);

-unsigned long part_start_io_acct(struct gendisk *disk, struct hd_struct **part,
- struct bio *bio);
-void part_end_io_acct(struct hd_struct *part, struct bio *bio,
+unsigned long part_start_io_acct(struct gendisk *disk,
+ struct block_device **part, struct bio *bio);
+void part_end_io_acct(struct block_device *part, struct bio *bio,
unsigned long start_time);

/**
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 6e16c264439bdb..77443a1031e373 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -131,8 +131,8 @@ enum {
struct disk_part_tbl {
struct rcu_head rcu_head;
int len;
- struct hd_struct __rcu *last_lookup;
- struct hd_struct __rcu *part[];
+ struct block_device __rcu *last_lookup;
+ struct block_device __rcu *part[];
};

struct disk_events;
diff --git a/include/linux/part_stat.h b/include/linux/part_stat.h
index 680de036691ef9..d2558121d48c00 100644
--- a/include/linux/part_stat.h
+++ b/include/linux/part_stat.h
@@ -25,26 +25,26 @@ struct disk_stats {
#define part_stat_unlock() preempt_enable()

#define part_stat_get_cpu(part, field, cpu) \
- (per_cpu_ptr((part)->bdev->bd_stats, (cpu))->field)
+ (per_cpu_ptr((part)->bd_stats, (cpu))->field)

#define part_stat_get(part, field) \
part_stat_get_cpu(part, field, smp_processor_id())

#define part_stat_read(part, field) \
({ \
- typeof((part)->bdev->bd_stats->field) res = 0; \
+ typeof((part)->bd_stats->field) res = 0; \
unsigned int _cpu; \
for_each_possible_cpu(_cpu) \
- res += per_cpu_ptr((part)->bdev->bd_stats, _cpu)->field; \
+ res += per_cpu_ptr((part)->bd_stats, _cpu)->field; \
res; \
})

-static inline void part_stat_set_all(struct hd_struct *part, int value)
+static inline void part_stat_set_all(struct block_device *part, int value)
{
int i;

for_each_possible_cpu(i)
- memset(per_cpu_ptr(part->bdev->bd_stats, i), value,
+ memset(per_cpu_ptr(part->bd_stats, i), value,
sizeof(struct disk_stats));
}

@@ -54,13 +54,12 @@ static inline void part_stat_set_all(struct hd_struct *part, int value)
part_stat_read(part, field[STAT_DISCARD]))

#define __part_stat_add(part, field, addnd) \
- __this_cpu_add((part)->bdev->bd_stats->field, addnd)
+ __this_cpu_add((part)->bd_stats->field, addnd)

#define part_stat_add(part, field, addnd) do { \
__part_stat_add((part), field, addnd); \
- if ((part)->partno) \
- __part_stat_add(part_to_disk((part))->part0->bd_part, \
- field, addnd); \
+ if ((part)->bd_partno) \
+ __part_stat_add(bdev_whole(part), field, addnd); \
} while (0)

#define part_stat_dec(part, field) \
--
2.29.2
Re: [PATCH 38/45] block: switch partition lookup to use struct block_device [ In reply to ]
On 2020/11/24 21:27, Christoph Hellwig wrote:
> Use struct block_device to lookup partitions on a disk. This removes
> all usage of struct hd_struct from the I/O path, and this allows removing
> the percpu refcount in struct hd_struct.
>
> Signed-off-by: Christoph Hellwig<hch@lst.de>
> ---
> block/bio.c | 4 +-
> block/blk-core.c | 66 ++++++++++++++----------------
> block/blk-flush.c | 2 +-
> block/blk-mq.c | 9 ++--
> block/blk-mq.h | 7 ++--
> block/blk.h | 4 +-
> block/genhd.c | 56 +++++++++++++------------
> block/partitions/core.c | 7 +---
> drivers/block/drbd/drbd_receiver.c | 2 +-
> drivers/block/drbd/drbd_worker.c | 2 +-
> drivers/block/zram/zram_drv.c | 2 +-
> drivers/md/bcache/request.c | 4 +-
> drivers/md/dm.c | 4 +-
> drivers/md/md.c | 4 +-
> drivers/nvme/target/admin-cmd.c | 20 ++++-----
> fs/ext4/super.c | 18 +++-----
> fs/ext4/sysfs.c | 10 +----
> fs/f2fs/f2fs.h | 2 +-
> fs/f2fs/super.c | 6 +--

For f2fs part,

Acked-by: Chao Yu <yuchao0@huawei.com>

Thanks,

> include/linux/blkdev.h | 8 ++--
> include/linux/genhd.h | 4 +-
> include/linux/part_stat.h | 17 ++++----
> 22 files changed, 120 insertions(+), 138 deletions(-)