On Thu, Nov 17, 2022 at 6:14 PM Vishal Moola (Oracle)
<vishal.moola@gmail.com> wrote:
>
> Converts move_extent_per_page() to use folios. This change removes
> 5 calls to compound_head() and is in preparation for the removal of
> the try_to_release_page() wrapper.
>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
> ---
> fs/ext4/move_extent.c | 52 ++++++++++++++++++++++++++-----------------
> 1 file changed, 31 insertions(+), 21 deletions(-)
>
> diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
> index 044e34cd835c..aa67eb240ca6 100644
> --- a/fs/ext4/move_extent.c
> +++ b/fs/ext4/move_extent.c
> @@ -253,6 +253,7 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
> {
> struct inode *orig_inode = file_inode(o_filp);
> struct page *pagep[2] = {NULL, NULL};
> + struct folio *folio[2] = {NULL, NULL};
> handle_t *handle;
> ext4_lblk_t orig_blk_offset, donor_blk_offset;
> unsigned long blocksize = orig_inode->i_sb->s_blocksize;
> @@ -313,6 +314,13 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
> * hold page's lock, if it is still the case data copy is not
> * necessary, just swap data blocks between orig and donor.
> */
> + folio[0] = page_folio(pagep[0]);
> + folio[1] = page_folio(pagep[1]);
> +
> + VM_BUG_ON_FOLIO(!folio_test_large(folio[0]), folio[0]);
> + VM_BUG_ON_FOLIO(!folio_test_large(folio[1]), folio[1]);
> + VM_BUG_ON_FOLIO(folio_nr_pages(folio[0]) != folio_nr_pages(folio[1]), folio[1]);
Looks like I got my assertions backward. We want to BUG if the folios are large,
or if they are different sizes. Disregard v2, its fixed in v3.
@@ -253,6 +253,7 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
{
struct inode *orig_inode = file_inode(o_filp);
struct page *pagep[2] = {NULL, NULL};
+ struct folio *folio[2] = {NULL, NULL};
handle_t *handle;
ext4_lblk_t orig_blk_offset, donor_blk_offset;
unsigned long blocksize = orig_inode->i_sb->s_blocksize;
@@ -313,6 +314,13 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
* hold page's lock, if it is still the case data copy is not
* necessary, just swap data blocks between orig and donor.
*/
+ folio[0] = page_folio(pagep[0]);
+ folio[1] = page_folio(pagep[1]);
+
+ VM_BUG_ON_FOLIO(!folio_test_large(folio[0]), folio[0]);
+ VM_BUG_ON_FOLIO(!folio_test_large(folio[1]), folio[1]);
+ VM_BUG_ON_FOLIO(folio_nr_pages(folio[0]) != folio_nr_pages(folio[1]), folio[1]);
+
if (unwritten) {
ext4_double_down_write_data_sem(orig_inode, donor_inode);
/* If any of extents in range became initialized we have to
@@ -331,10 +339,10 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
ext4_double_up_write_data_sem(orig_inode, donor_inode);
goto data_copy;
}
- if ((page_has_private(pagep[0]) &&
- !try_to_release_page(pagep[0], 0)) ||
- (page_has_private(pagep[1]) &&
- !try_to_release_page(pagep[1], 0))) {
+ if ((folio_has_private(folio[0]) &&
+ !filemap_release_folio(folio[0], 0)) ||
+ (folio_has_private(folio[1]) &&
+ !filemap_release_folio(folio[1], 0))) {
*err = -EBUSY;
goto drop_data_sem;
}
@@ -344,19 +352,21 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
block_len_in_page, 1, err);
drop_data_sem:
ext4_double_up_write_data_sem(orig_inode, donor_inode);
- goto unlock_pages;
+ goto unlock_folios;
}
data_copy:
- *err = mext_page_mkuptodate(pagep[0], from, from + replaced_size);
+ *err = mext_page_mkuptodate(&folio[0]->page, from, from + replaced_size);
if (*err)
- goto unlock_pages;
+ goto unlock_folios;
/* At this point all buffers in range are uptodate, old mapping layout
* is no longer required, try to drop it now. */
- if ((page_has_private(pagep[0]) && !try_to_release_page(pagep[0], 0)) ||
- (page_has_private(pagep[1]) && !try_to_release_page(pagep[1], 0))) {
+ if ((folio_has_private(folio[0]) &&
+ !filemap_release_folio(folio[0], 0)) ||
+ (folio_has_private(folio[1]) &&
+ !filemap_release_folio(folio[1], 0))) {
*err = -EBUSY;
- goto unlock_pages;
+ goto unlock_folios;
}
ext4_double_down_write_data_sem(orig_inode, donor_inode);
replaced_count = ext4_swap_extents(handle, orig_inode, donor_inode,
@@ -369,13 +379,13 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
replaced_size =
block_len_in_page << orig_inode->i_blkbits;
} else
- goto unlock_pages;
+ goto unlock_folios;
}
/* Perform all necessary steps similar write_begin()/write_end()
* but keeping in mind that i_size will not change */
- if (!page_has_buffers(pagep[0]))
- create_empty_buffers(pagep[0], 1 << orig_inode->i_blkbits, 0);
- bh = page_buffers(pagep[0]);
+ if (!folio_buffers(folio[0]))
+ create_empty_buffers(&folio[0]->page, 1 << orig_inode->i_blkbits, 0);
+ bh = folio_buffers(folio[0]);
for (i = 0; i < data_offset_in_page; i++)
bh = bh->b_this_page;
for (i = 0; i < block_len_in_page; i++) {
@@ -385,7 +395,7 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
bh = bh->b_this_page;
}
if (!*err)
- *err = block_commit_write(pagep[0], from, from + replaced_size);
+ *err = block_commit_write(&folio[0]->page, from, from + replaced_size);
if (unlikely(*err < 0))
goto repair_branches;
@@ -395,11 +405,11 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
*err = ext4_jbd2_inode_add_write(handle, orig_inode,
(loff_t)orig_page_offset << PAGE_SHIFT, replaced_size);
-unlock_pages:
- unlock_page(pagep[0]);
- put_page(pagep[0]);
- unlock_page(pagep[1]);
- put_page(pagep[1]);
+unlock_folios:
+ folio_unlock(folio[0]);
+ folio_put(folio[0]);
+ folio_unlock(folio[1]);
+ folio_put(folio[1]);
stop_journal:
ext4_journal_stop(handle);
if (*err == -ENOSPC &&
@@ -430,7 +440,7 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
*err = -EIO;
}
replaced_count = 0;
- goto unlock_pages;
+ goto unlock_folios;
}
/**