[PATCH v2 07/10] block: use sectors_to_npage() and PAGE_SECTORS to clean up code

From: Zhen Lei
Date: Thu May 07 2020 - 03:56:16 EST


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

Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
---
block/blk-settings.c | 6 +++---
block/partitions/core.c | 5 ++---
2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 14397b4c4b53..171665ed8318 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -150,7 +150,7 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
unsigned int max_sectors;

if ((max_hw_sectors << 9) < PAGE_SIZE) {
- max_hw_sectors = 1 << (PAGE_SHIFT - 9);
+ max_hw_sectors = PAGE_SECTORS;
printk(KERN_INFO "%s: set to minimum %d\n",
__func__, max_hw_sectors);
}
@@ -159,7 +159,7 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
max_sectors = min_not_zero(max_hw_sectors, limits->max_dev_sectors);
max_sectors = min_t(unsigned int, max_sectors, BLK_DEF_MAX_SECTORS);
limits->max_sectors = max_sectors;
- q->backing_dev_info->io_pages = max_sectors >> (PAGE_SHIFT - 9);
+ q->backing_dev_info->io_pages = sectors_to_npage(max_sectors);
}
EXPORT_SYMBOL(blk_queue_max_hw_sectors);

@@ -630,7 +630,7 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
}

t->backing_dev_info->io_pages =
- t->limits.max_sectors >> (PAGE_SHIFT - 9);
+ sectors_to_npage(t->limits.max_sectors);
}
EXPORT_SYMBOL(disk_stack_limits);

diff --git a/block/partitions/core.c b/block/partitions/core.c
index 9ef48a8cff86..4859739a2414 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -640,8 +640,7 @@ void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p)
return NULL;
}

- page = read_mapping_page(mapping,
- (pgoff_t)(n >> (PAGE_SHIFT - 9)), NULL);
+ page = read_mapping_page(mapping, (pgoff_t)sectors_to_npage(n), NULL);
if (IS_ERR(page))
goto out;
if (PageError(page))
@@ -649,7 +648,7 @@ void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p)

p->v = page;
return (unsigned char *)page_address(page) +
- ((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << SECTOR_SHIFT);
+ ((n & (PAGE_SECTORS - 1)) << SECTOR_SHIFT);
out_put_page:
put_page(page);
out:
--
2.26.0.106.g9fadedd