[PATCH 06/29] dax: move the partition alignment check into fs_dax_get_by_bdev

Christoph Hellwig
2021-11-09T08:33:34Z

fs_dax_get_by_bdev is the primary interface to find a dax device for a
block device, so move the partition alignment check there instead of
wiring it up through ->dax_supported.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/dax/super.c | 23 ++++++-----------------
1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/drivers/dax/super.c b/drivers/dax/super.c
index 04fc680542e8d..482fe775324a4 100644
--- a/drivers/dax/super.c
+++ b/drivers/dax/super.c
@@ -93,6 +93,12 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
if (!blk_queue_dax(bdev->bd_disk->queue))
return NULL;

+ if ((get_start_sect(bdev) * SECTOR_SIZE) % PAGE_SIZE ||
+ (bdev_nr_sectors(bdev) * SECTOR_SIZE) % PAGE_SIZE) {
+ pr_info("%pg: error: unaligned partition for dax\n", bdev);
+ return NULL;
+ }
+
id = dax_read_lock();
dax_dev = xa_load(&dax_hosts, (unsigned long)bdev->bd_disk);
if (!dax_dev || !dax_alive(dax_dev) || !igrab(&dax_dev->inode))
@@ -107,10 +113,6 @@ bool generic_fsdax_supported(struct dax_device *dax_dev,
struct block_device *bdev, int blocksize, sector_t start,
sector_t sectors)
{
- pgoff_t pgoff, pgoff_end;
- sector_t last_page;
- int err;
-
if (blocksize != PAGE_SIZE) {
pr_info("%pg: error: unsupported blocksize for dax\n", bdev);
return false;
@@ -121,19 +123,6 @@ bool generic_fsdax_supported(struct dax_device *dax_dev,
return false;
}

- err = bdev_dax_pgoff(bdev, start, PAGE_SIZE, &pgoff);
- if (err) {
- pr_info("%pg: error: unaligned partition for dax\n", bdev);
- return false;
- }
-
- last_page = PFN_DOWN((start + sectors - 1) * 512) * PAGE_SIZE / 512;
- err = bdev_dax_pgoff(bdev, last_page, PAGE_SIZE, &pgoff_end);
- if (err) {
- pr_info("%pg: error: unaligned partition for dax\n", bdev);
- return false;
- }
-
return true;
}
EXPORT_SYMBOL_GPL(generic_fsdax_supported);
--
2.30.2