Re: [PATCH 06/29] dax: move the partition alignment check into fs_dax_get_by_bdev
From: "Darrick J. Wong" <djwong@kernel.org>
Date: 2021-11-23 22:26:00
Also in:
dm-devel, linux-ext4, linux-fsdevel, linux-xfs, nvdimm
On Tue, Nov 09, 2021 at 09:32:46AM +0100, Christoph Hellwig wrote:
quoted hunk ↗ jump to hunk
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) {
Do we have to be careful about 64-bit division here, or do we not support DAX on 32-bit?
+ pr_info("%pg: error: unaligned partition for dax\n", bdev);I also wonder if this should be ratelimited...? --D
quoted hunk ↗ jump to hunk
+ 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