[PATCH v2 08/10] md: use sectors_to_npage() and npage_to_sectors() to clean up code

[Zhen Lei]

1. Replace ">> (PAGE_SHIFT - 9)" with sectors_to_npage()
2. Replace "<< (PAGE_SHIFT - 9)" with npage_to_sectors()

Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
 drivers/md/dm-table.c    |  2 +-
 drivers/md/raid1.c       |  2 +-
 drivers/md/raid10.c      |  2 +-
 drivers/md/raid5-cache.c | 11 +++++------
 4 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 0a2cc197f62b..e1f176bda528 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1964,7 +1964,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
 #endif
 
 	/* Allow reads to exceed readahead limits */
-	q->backing_dev_info->io_pages = limits->max_sectors >> (PAGE_SHIFT - 9);
+	q->backing_dev_info->io_pages = sectors_to_npage(limits->max_sectors);
 }
 
 unsigned int dm_table_get_num_targets(struct dm_table *t)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index cd810e195086..44ffe1b6d77a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2129,7 +2129,7 @@ static void process_checks(struct r1bio *r1_bio)
 	int vcnt;
 
 	/* Fix variable parts of all bios */
-	vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
+	vcnt = sectors_to_npage(r1_bio->sectors + PAGE_SIZE / 512 - 1);
 	for (i = 0; i < conf->raid_disks * 2; i++) {
 		blk_status_t status;
 		struct bio *b = r1_bio->bios[i];
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index ec136e44aef7..948afe720fca 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2029,7 +2029,7 @@ static void sync_request_write(struct mddev *mddev, struct r10bio *r10_bio)
 	fbio->bi_iter.bi_idx = 0;
 	fpages = get_resync_pages(fbio)->pages;
 
-	vcnt = (r10_bio->sectors + (PAGE_SIZE >> 9) - 1) >> (PAGE_SHIFT - 9);
+	vcnt = sectors_to_npage(r10_bio->sectors + (PAGE_SIZE >> 9) - 1);
 	/* now find blocks with errors */
 	for (i=0 ; i < conf->copies ; i++) {
 		int  j, d;
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 9b6da759dca2..0b9cd810466a 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -832,8 +832,7 @@ static void r5l_append_payload_meta(struct r5l_log *log, u16 type,
 	payload = page_address(io->meta_page) + io->meta_offset;
 	payload->header.type = cpu_to_le16(type);
 	payload->header.flags = cpu_to_le16(0);
-	payload->size = cpu_to_le32((1 + !!checksum2_valid) <<
-				    (PAGE_SHIFT - 9));
+	payload->size = cpu_to_le32(npage_to_sectors(1 + !!checksum2_valid));
 	payload->location = cpu_to_le64(location);
 	payload->checksum[0] = cpu_to_le32(checksum1);
 	if (checksum2_valid)
@@ -1042,7 +1041,7 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
 
 	mutex_lock(&log->io_mutex);
 	/* meta + data */
-	reserve = (1 + write_disks) << (PAGE_SHIFT - 9);
+	reserve = npage_to_sectors(1 + write_disks);
 
 	if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) {
 		if (!r5l_has_free_space(log, reserve)) {
@@ -2053,7 +2052,7 @@ r5l_recovery_verify_data_checksum_for_mb(struct r5l_log *log,
 						  le32_to_cpu(payload->size));
 			mb_offset += sizeof(struct r5l_payload_data_parity) +
 				sizeof(__le32) *
-				(le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
+				sectors_to_npage(le32_to_cpu(payload->size));
 		}
 
 	}
@@ -2199,7 +2198,7 @@ r5c_recovery_analyze_meta_block(struct r5l_log *log,
 
 		mb_offset += sizeof(struct r5l_payload_data_parity) +
 			sizeof(__le32) *
-			(le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
+			sectors_to_npage(le32_to_cpu(payload->size));
 	}
 
 	return 0;
@@ -2916,7 +2915,7 @@ int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh)
 
 	mutex_lock(&log->io_mutex);
 	/* meta + data */
-	reserve = (1 + pages) << (PAGE_SHIFT - 9);
+	reserve = npage_to_sectors(1 + pages);
 
 	if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) &&
 	    sh->log_start == MaxSector)
-- 
2.26.0.106.g9fadedd