On 6/21/23 10:38, Pankaj Raghav wrote:
From: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Automatically set the minimum mapping order for block devices in
set_init_blocksize(). The mapping order will be set only when the block
device uses iomap based aops.
Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
---
block/bdev.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/block/bdev.c b/block/bdev.c
index 9bb54d9d02a6..db8cede8a320 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -126,6 +126,7 @@ static void set_init_blocksize(struct block_device *bdev)
{
unsigned int bsize = bdev_logical_block_size(bdev);
loff_t size = i_size_read(bdev->bd_inode);
+ int order, folio_order;
while (bsize < PAGE_SIZE) {
if (size & bsize)
@@ -133,6 +134,14 @@ static void set_init_blocksize(struct block_device *bdev)
bsize <<= 1;
}
bdev->bd_inode->i_blkbits = blksize_bits(bsize);
+ order = bdev->bd_inode->i_blkbits - PAGE_SHIFT;
+ folio_order = mapping_min_folio_order(bdev->bd_inode->i_mapping);
+
+ if (!IS_ENABLED(CONFIG_BUFFER_HEAD)) {
+ /* Do not allow changing the folio order after it is set */
+ WARN_ON_ONCE(folio_order && (folio_order != order));
+ mapping_set_folio_orders(bdev->bd_inode->i_mapping, order, 31);
+ }
}
int set_blocksize(struct block_device *bdev, int size)
This really has nothing to do with buffer heads.
In fact, I've got a patchset to make it work _with_ buffer heads.
So please, don't make it conditional on CONFIG_BUFFER_HEAD.
And we should be calling into 'mapping_set_folio_order()' only if the
'order' argument is larger than PAGE_ORDER, otherwise we end up enabling
large folio support for _every_ block device.
Which I doubt we want.
Cheers,
Hannes
