buffer: calculate block number inside folio_init_buffers()

The calculation of block from index doesn't work for devices with a block
size larger than PAGE_SIZE as we end up shifting by a negative number. 
Instead, calculate the number of the first block from the folio's position
in the block device.  We no longer need to pass sizebits to
grow_dev_folio().

Link: https://lkml.kernel.org/r/20231109210608.2252323-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-11-09 21:06:03 +00:00 committed by Andrew Morton
parent 6d840a1877
commit 382497ada0
1 changed files with 6 additions and 7 deletions

View File

@ -995,11 +995,12 @@ static sector_t blkdev_max_block(struct block_device *bdev, unsigned int size)
* Initialise the state of a blockdev folio's buffers.
*/
static sector_t folio_init_buffers(struct folio *folio,
struct block_device *bdev, sector_t block, int size)
struct block_device *bdev, unsigned size)
{
struct buffer_head *head = folio_buffers(folio);
struct buffer_head *bh = head;
bool uptodate = folio_test_uptodate(folio);
sector_t block = div_u64(folio_pos(folio), size);
sector_t end_block = blkdev_max_block(bdev, size);
do {
@ -1032,7 +1033,7 @@ static sector_t folio_init_buffers(struct folio *folio,
* we succeeded, or the caller should retry.
*/
static bool grow_dev_folio(struct block_device *bdev, sector_t block,
pgoff_t index, unsigned size, int sizebits, gfp_t gfp)
pgoff_t index, unsigned size, gfp_t gfp)
{
struct inode *inode = bdev->bd_inode;
struct folio *folio;
@ -1047,8 +1048,7 @@ static bool grow_dev_folio(struct block_device *bdev, sector_t block,
bh = folio_buffers(folio);
if (bh) {
if (bh->b_size == size) {
end_block = folio_init_buffers(folio, bdev,
(sector_t)index << sizebits, size);
end_block = folio_init_buffers(folio, bdev, size);
goto unlock;
}
@ -1069,8 +1069,7 @@ static bool grow_dev_folio(struct block_device *bdev, sector_t block,
*/
spin_lock(&inode->i_mapping->private_lock);
link_dev_buffers(folio, bh);
end_block = folio_init_buffers(folio, bdev,
(sector_t)index << sizebits, size);
end_block = folio_init_buffers(folio, bdev, size);
spin_unlock(&inode->i_mapping->private_lock);
unlock:
folio_unlock(folio);
@ -1105,7 +1104,7 @@ static bool grow_buffers(struct block_device *bdev, sector_t block,
}
/* Create a folio with the proper size buffers */
return grow_dev_folio(bdev, block, index, size, sizebits, gfp);
return grow_dev_folio(bdev, block, index, size, gfp);
}
static struct buffer_head *