Commit e8dfc854 authored by Vishal Moola (Oracle)'s avatar Vishal Moola (Oracle) Committed by Andrew Morton
Browse files

ext4: convert mext_page_double_lock() to mext_folio_double_lock() 

Convert mext_page_double_lock() to use folios.  This change saves 146
bytes of kernel text.  It also removes 6 calls to compound_head() and 2
calls to folio_file_page().

Link: https://lkml.kernel.org/r/20221207181009.4016-1-vishal.moola@gmail.com


Signed-off-by: default avatarVishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent f4d9139f

fs/ext4/move_extent.c

+23 −23
Original line number Diff line number Diff line
@@ -110,22 +110,23 @@ mext_check_coverage(struct inode *inode, ext4_lblk_t from, ext4_lblk_t count, 
}



/**

 * mext_page_double_lock - Grab and lock pages on both @inode1 and @inode2

 * mext_folio_double_lock - Grab and lock folio on both @inode1 and @inode2

 *

 * @inode1:	the inode structure

 * @inode2:	the inode structure

 * @index1:	page index

 * @index2:	page index

 * @page:	result page vector

 * @index1:	folio index

 * @index2:	folio index

 * @folio:	result folio vector

 *

 * Grab two locked pages for inode's by inode order

 * Grab two locked folio for inode's by inode order

 */

static int

mext_page_double_lock(struct inode *inode1, struct inode *inode2,

		      pgoff_t index1, pgoff_t index2, struct page *page[2])

mext_folio_double_lock(struct inode *inode1, struct inode *inode2,

		      pgoff_t index1, pgoff_t index2, struct folio *folio[2])

{

	struct address_space *mapping[2];

	unsigned int flags;

	unsigned fgp_flags = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE;



	BUG_ON(!inode1 || !inode2);

	if (inode1 < inode2) {
@@ -138,28 +139,30 @@ mext_page_double_lock(struct inode *inode1, struct inode *inode2, 
	}



	flags = memalloc_nofs_save();

	page[0] = grab_cache_page_write_begin(mapping[0], index1);

	if (!page[0]) {

	folio[0] = __filemap_get_folio(mapping[0], index1, fgp_flags,

			mapping_gfp_mask(mapping[0]));

	if (!folio[0]) {

		memalloc_nofs_restore(flags);

		return -ENOMEM;

	}



	page[1] = grab_cache_page_write_begin(mapping[1], index2);

	folio[1] = __filemap_get_folio(mapping[1], index2, fgp_flags,

			mapping_gfp_mask(mapping[1]));

	memalloc_nofs_restore(flags);

	if (!page[1]) {

		unlock_page(page[0]);

		put_page(page[0]);

	if (!folio[1]) {

		folio_unlock(folio[0]);

		folio_put(folio[0]);

		return -ENOMEM;

	}

	/*

	 * grab_cache_page_write_begin() may not wait on page's writeback if

	 * __filemap_get_folio() may not wait on folio's writeback if

	 * BDI not demand that. But it is reasonable to be very conservative

	 * here and explicitly wait on page's writeback

	 * here and explicitly wait on folio's writeback

	 */

	wait_on_page_writeback(page[0]);

	wait_on_page_writeback(page[1]);

	folio_wait_writeback(folio[0]);

	folio_wait_writeback(folio[1]);

	if (inode1 > inode2)

		swap(page[0], page[1]);

		swap(folio[0], folio[1]);



	return 0;

}
@@ -252,7 +255,6 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, 
		     int block_len_in_page, int unwritten, int *err)

{

	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;
@@ -303,8 +305,8 @@ move_extent_per_page(struct file *o_filp, struct inode *donor_inode, 


	replaced_size = data_size;



	*err = mext_page_double_lock(orig_inode, donor_inode, orig_page_offset,

				     donor_page_offset, pagep);

	*err = mext_folio_double_lock(orig_inode, donor_inode, orig_page_offset,

				     donor_page_offset, folio);

	if (unlikely(*err < 0))

		goto stop_journal;

	/*
@@ -314,8 +316,6 @@ 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]);