The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9b5948267adc9e689da609eb61cf7ed49cae5fa8 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka <mpatocka@xxxxxxxxxx> Date: Fri, 8 Jan 2021 11:15:56 -0500 Subject: [PATCH] dm integrity: fix flush with external metadata device With external metadata device, flush requests are not passed down to the data device. Fix this by submitting the flush request in dm_integrity_flush_buffers. In order to not degrade performance, we overlap the data device flush with the metadata device flush. Reported-by: Lukas Straub <lukasstraub2@xxxxxx> Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index 9c1a86bde658..fce4cbf9529d 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -1534,6 +1534,12 @@ sector_t dm_bufio_get_device_size(struct dm_bufio_client *c) } EXPORT_SYMBOL_GPL(dm_bufio_get_device_size); +struct dm_io_client *dm_bufio_get_dm_io_client(struct dm_bufio_client *c) +{ + return c->dm_io; +} +EXPORT_SYMBOL_GPL(dm_bufio_get_dm_io_client); + sector_t dm_bufio_get_block_number(struct dm_buffer *b) { return b->block; diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 5a7a1b90e671..11c7c538f7a9 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1379,12 +1379,52 @@ static int dm_integrity_rw_tag(struct dm_integrity_c *ic, unsigned char *tag, se #undef MAY_BE_HASH } -static void dm_integrity_flush_buffers(struct dm_integrity_c *ic) +struct flush_request { + struct dm_io_request io_req; + struct dm_io_region io_reg; + struct dm_integrity_c *ic; + struct completion comp; +}; + +static void flush_notify(unsigned long error, void *fr_) +{ + struct flush_request *fr = fr_; + if (unlikely(error != 0)) + dm_integrity_io_error(fr->ic, "flusing disk cache", -EIO); + complete(&fr->comp); +} + +static void dm_integrity_flush_buffers(struct dm_integrity_c *ic, bool flush_data) { int r; + + struct flush_request fr; + + if (!ic->meta_dev) + flush_data = false; + if (flush_data) { + fr.io_req.bi_op = REQ_OP_WRITE, + fr.io_req.bi_op_flags = REQ_PREFLUSH | REQ_SYNC, + fr.io_req.mem.type = DM_IO_KMEM, + fr.io_req.mem.ptr.addr = NULL, + fr.io_req.notify.fn = flush_notify, + fr.io_req.notify.context = &fr; + fr.io_req.client = dm_bufio_get_dm_io_client(ic->bufio), + fr.io_reg.bdev = ic->dev->bdev, + fr.io_reg.sector = 0, + fr.io_reg.count = 0, + fr.ic = ic; + init_completion(&fr.comp); + r = dm_io(&fr.io_req, 1, &fr.io_reg, NULL); + BUG_ON(r); + } + r = dm_bufio_write_dirty_buffers(ic->bufio); if (unlikely(r)) dm_integrity_io_error(ic, "writing tags", r); + + if (flush_data) + wait_for_completion(&fr.comp); } static void sleep_on_endio_wait(struct dm_integrity_c *ic) @@ -2110,7 +2150,7 @@ static void dm_integrity_map_continue(struct dm_integrity_io *dio, bool from_map if (unlikely(dio->op == REQ_OP_DISCARD) && likely(ic->mode != 'D')) { integrity_metadata(&dio->work); - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, false); dio->in_flight = (atomic_t)ATOMIC_INIT(1); dio->completion = NULL; @@ -2195,7 +2235,7 @@ static void integrity_commit(struct work_struct *w) flushes = bio_list_get(&ic->flush_bio_list); if (unlikely(ic->mode != 'J')) { spin_unlock_irq(&ic->endio_wait.lock); - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, true); goto release_flush_bios; } @@ -2409,7 +2449,7 @@ static void do_journal_write(struct dm_integrity_c *ic, unsigned write_start, complete_journal_op(&comp); wait_for_completion_io(&comp.comp); - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, true); } static void integrity_writer(struct work_struct *w) @@ -2451,7 +2491,7 @@ static void recalc_write_super(struct dm_integrity_c *ic) { int r; - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, false); if (dm_integrity_failed(ic)) return; @@ -2654,7 +2694,7 @@ static void bitmap_flush_work(struct work_struct *work) unsigned long limit; struct bio *bio; - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, false); range.logical_sector = 0; range.n_sectors = ic->provided_data_sectors; @@ -2663,9 +2703,7 @@ static void bitmap_flush_work(struct work_struct *work) add_new_range_and_wait(ic, &range); spin_unlock_irq(&ic->endio_wait.lock); - dm_integrity_flush_buffers(ic); - if (ic->meta_dev) - blkdev_issue_flush(ic->dev->bdev, GFP_NOIO); + dm_integrity_flush_buffers(ic, true); limit = ic->provided_data_sectors; if (ic->sb->flags & cpu_to_le32(SB_FLAG_RECALCULATING)) { @@ -2934,11 +2972,11 @@ static void dm_integrity_postsuspend(struct dm_target *ti) if (ic->meta_dev) queue_work(ic->writer_wq, &ic->writer_work); drain_workqueue(ic->writer_wq); - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, true); } if (ic->mode == 'B') { - dm_integrity_flush_buffers(ic); + dm_integrity_flush_buffers(ic, true); #if 1 /* set to 0 to test bitmap replay code */ init_journal(ic, 0, ic->journal_sections, 0); diff --git a/include/linux/dm-bufio.h b/include/linux/dm-bufio.h index 29d255fdd5d6..90bd558a17f5 100644 --- a/include/linux/dm-bufio.h +++ b/include/linux/dm-bufio.h @@ -150,6 +150,7 @@ void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n); unsigned dm_bufio_get_block_size(struct dm_bufio_client *c); sector_t dm_bufio_get_device_size(struct dm_bufio_client *c); +struct dm_io_client *dm_bufio_get_dm_io_client(struct dm_bufio_client *c); sector_t dm_bufio_get_block_number(struct dm_buffer *b); void *dm_bufio_get_block_data(struct dm_buffer *b); void *dm_bufio_get_aux_data(struct dm_buffer *b);