[PATCH 6.12 093/119] btrfs: remove btrfs_fs_info::sectors_per_page

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Qu Wenruo <wqu@suse.com>

[ Upstream commit 619611e87fcca1fdaa67c2bf6b030863ab90216e ]

For the future large folio support, our filemap can have folios with
different sizes, thus we can no longer rely on a fixed blocks_per_page
value.

To prepare for that future, here we do:

- Remove btrfs_fs_info::sectors_per_page

- Introduce a helper, btrfs_blocks_per_folio()
  Which uses the folio size to calculate the number of blocks for each
  folio.

- Migrate the existing btrfs_fs_info::sectors_per_page to use that
  helper
  There are some exceptions:

  * Metadata nodesize < page size support
    In the future, even if we support large folios, we will only
    allocate a folio that matches our nodesize.
    Thus we won't have a folio covering multiple metadata unless
    nodesize < page size.

  * Existing subpage bitmap dump
    We use a single unsigned long to store the bitmap.
    That means until we change the bitmap dumping code, our upper limit
    for folio size will only be 256K (4K block size, 64 bit unsigned
    long).

  * btrfs_is_subpage() check
    This will be migrated into a future patch.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: e9e3b22ddfa7 ("btrfs: fix beyond-EOF write handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/btrfs/disk-io.c   |    1 
 fs/btrfs/extent_io.c |   26 +++++++-----
 fs/btrfs/fs.h        |    7 ++-
 fs/btrfs/subpage.c   |  104 ++++++++++++++++++++++++++++++---------------------
 4 files changed, 84 insertions(+), 54 deletions(-)

--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3320,7 +3320,6 @@ int __cold open_ctree(struct super_block
 	fs_info->nodesize = nodesize;
 	fs_info->sectorsize = sectorsize;
 	fs_info->sectorsize_bits = ilog2(sectorsize);
-	fs_info->sectors_per_page = (PAGE_SIZE >> fs_info->sectorsize_bits);
 	fs_info->csums_per_leaf = BTRFS_MAX_ITEM_SIZE(fs_info) / fs_info->csum_size;
 	fs_info->stripesize = stripesize;
 
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1182,7 +1182,7 @@ static bool find_next_delalloc_bitmap(st
 {
 	struct btrfs_fs_info *fs_info = folio_to_fs_info(folio);
 	const u64 folio_start = folio_pos(folio);
-	const unsigned int bitmap_size = fs_info->sectors_per_page;
+	const unsigned int bitmap_size = btrfs_blocks_per_folio(fs_info, folio);
 	unsigned int start_bit;
 	unsigned int first_zero;
 	unsigned int first_set;
@@ -1224,6 +1224,7 @@ static noinline_for_stack int writepage_
 	const bool is_subpage = btrfs_is_subpage(fs_info, folio->mapping);
 	const u64 page_start = folio_pos(folio);
 	const u64 page_end = page_start + folio_size(folio) - 1;
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
 	unsigned long delalloc_bitmap = 0;
 	/*
 	 * Save the last found delalloc end. As the delalloc end can go beyond
@@ -1249,13 +1250,13 @@ static noinline_for_stack int writepage_
 
 	/* Save the dirty bitmap as our submission bitmap will be a subset of it. */
 	if (btrfs_is_subpage(fs_info, inode->vfs_inode.i_mapping)) {
-		ASSERT(fs_info->sectors_per_page > 1);
+		ASSERT(blocks_per_folio > 1);
 		btrfs_get_subpage_dirty_bitmap(fs_info, folio, &bio_ctrl->submit_bitmap);
 	} else {
 		bio_ctrl->submit_bitmap = 1;
 	}
 
-	for_each_set_bit(bit, &bio_ctrl->submit_bitmap, fs_info->sectors_per_page) {
+	for_each_set_bit(bit, &bio_ctrl->submit_bitmap, blocks_per_folio) {
 		u64 start = page_start + (bit << fs_info->sectorsize_bits);
 
 		btrfs_folio_set_lock(fs_info, folio, start, fs_info->sectorsize);
@@ -1328,7 +1329,7 @@ static noinline_for_stack int writepage_
 					     btrfs_root_id(inode->root),
 					     btrfs_ino(inode),
 					     folio_pos(folio),
-					     fs_info->sectors_per_page,
+					     blocks_per_folio,
 					     &bio_ctrl->submit_bitmap,
 					     found_start, found_len, ret);
 		} else {
@@ -1373,7 +1374,7 @@ static noinline_for_stack int writepage_
 		unsigned int bitmap_size = min(
 				(last_finished_delalloc_end - page_start) >>
 				fs_info->sectorsize_bits,
-				fs_info->sectors_per_page);
+				blocks_per_folio);
 
 		for_each_set_bit(bit, &bio_ctrl->submit_bitmap, bitmap_size)
 			btrfs_mark_ordered_io_finished(inode, folio,
@@ -1397,7 +1398,7 @@ out:
 	 * If all ranges are submitted asynchronously, we just need to account
 	 * for them here.
 	 */
-	if (bitmap_empty(&bio_ctrl->submit_bitmap, fs_info->sectors_per_page)) {
+	if (bitmap_empty(&bio_ctrl->submit_bitmap, blocks_per_folio)) {
 		wbc->nr_to_write -= delalloc_to_write;
 		return 1;
 	}
@@ -1498,6 +1499,7 @@ static noinline_for_stack int extent_wri
 	bool submitted_io = false;
 	int found_error = 0;
 	const u64 folio_start = folio_pos(folio);
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
 	u64 cur;
 	int bit;
 	int ret = 0;
@@ -1516,11 +1518,11 @@ static noinline_for_stack int extent_wri
 	for (cur = start; cur < start + len; cur += fs_info->sectorsize)
 		set_bit((cur - folio_start) >> fs_info->sectorsize_bits, &range_bitmap);
 	bitmap_and(&bio_ctrl->submit_bitmap, &bio_ctrl->submit_bitmap, &range_bitmap,
-		   fs_info->sectors_per_page);
+		   blocks_per_folio);
 
 	bio_ctrl->end_io_func = end_bbio_data_write;
 
-	for_each_set_bit(bit, &bio_ctrl->submit_bitmap, fs_info->sectors_per_page) {
+	for_each_set_bit(bit, &bio_ctrl->submit_bitmap, blocks_per_folio) {
 		cur = folio_pos(folio) + (bit << fs_info->sectorsize_bits);
 
 		if (cur >= i_size) {
@@ -1595,6 +1597,7 @@ static int extent_writepage(struct folio
 	size_t pg_offset;
 	loff_t i_size = i_size_read(&inode->vfs_inode);
 	unsigned long end_index = i_size >> PAGE_SHIFT;
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
 
 	trace_extent_writepage(folio, &inode->vfs_inode, bio_ctrl->wbc);
 
@@ -1634,7 +1637,7 @@ static int extent_writepage(struct folio
 		btrfs_err_rl(fs_info,
 "failed to submit blocks, root=%lld inode=%llu folio=%llu submit_bitmap=%*pbl: %d",
 			     btrfs_root_id(inode->root), btrfs_ino(inode),
-			     folio_pos(folio), fs_info->sectors_per_page,
+			     folio_pos(folio), blocks_per_folio,
 			     &bio_ctrl->submit_bitmap, ret);
 
 	bio_ctrl->wbc->nr_to_write--;
@@ -1929,9 +1932,10 @@ static int submit_eb_subpage(struct foli
 	u64 folio_start = folio_pos(folio);
 	int bit_start = 0;
 	int sectors_per_node = fs_info->nodesize >> fs_info->sectorsize_bits;
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
 
 	/* Lock and write each dirty extent buffers in the range */
-	while (bit_start < fs_info->sectors_per_page) {
+	while (bit_start < blocks_per_folio) {
 		struct btrfs_subpage *subpage = folio_get_private(folio);
 		struct extent_buffer *eb;
 		unsigned long flags;
@@ -1947,7 +1951,7 @@ static int submit_eb_subpage(struct foli
 			break;
 		}
 		spin_lock_irqsave(&subpage->lock, flags);
-		if (!test_bit(bit_start + btrfs_bitmap_nr_dirty * fs_info->sectors_per_page,
+		if (!test_bit(bit_start + btrfs_bitmap_nr_dirty * blocks_per_folio,
 			      subpage->bitmaps)) {
 			spin_unlock_irqrestore(&subpage->lock, flags);
 			spin_unlock(&folio->mapping->i_private_lock);
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -708,7 +708,6 @@ struct btrfs_fs_info {
 	 * running.
 	 */
 	refcount_t scrub_workers_refcnt;
-	u32 sectors_per_page;
 	struct workqueue_struct *scrub_workers;
 
 	struct btrfs_discard_ctl discard_ctl;
@@ -976,6 +975,12 @@ static inline u32 count_max_extents(cons
 	return div_u64(size + fs_info->max_extent_size - 1, fs_info->max_extent_size);
 }
 
+static inline unsigned int btrfs_blocks_per_folio(const struct btrfs_fs_info *fs_info,
+						  const struct folio *folio)
+{
+	return folio_size(folio) >> fs_info->sectorsize_bits;
+}
+
 bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
 			enum btrfs_exclusive_operation type);
 bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
--- a/fs/btrfs/subpage.c
+++ b/fs/btrfs/subpage.c
@@ -93,6 +93,9 @@ int btrfs_attach_subpage(const struct bt
 {
 	struct btrfs_subpage *subpage;
 
+	/* For metadata we don't support large folio yet. */
+	ASSERT(!folio_test_large(folio));
+
 	/*
 	 * We have cases like a dummy extent buffer page, which is not mapped
 	 * and doesn't need to be locked.
@@ -134,7 +137,8 @@ struct btrfs_subpage *btrfs_alloc_subpag
 	ASSERT(fs_info->sectorsize < PAGE_SIZE);
 
 	real_size = struct_size(ret, bitmaps,
-			BITS_TO_LONGS(btrfs_bitmap_nr_max * fs_info->sectors_per_page));
+			BITS_TO_LONGS(btrfs_bitmap_nr_max *
+				      (PAGE_SIZE >> fs_info->sectorsize_bits)));
 	ret = kzalloc(real_size, GFP_NOFS);
 	if (!ret)
 		return ERR_PTR(-ENOMEM);
@@ -211,11 +215,13 @@ static void btrfs_subpage_assert(const s
 
 #define subpage_calc_start_bit(fs_info, folio, name, start, len)	\
 ({									\
-	unsigned int __start_bit;						\
+	unsigned int __start_bit;					\
+	const unsigned int blocks_per_folio =				\
+			   btrfs_blocks_per_folio(fs_info, folio);	\
 									\
 	btrfs_subpage_assert(fs_info, folio, start, len);		\
 	__start_bit = offset_in_page(start) >> fs_info->sectorsize_bits; \
-	__start_bit += fs_info->sectors_per_page * btrfs_bitmap_nr_##name; \
+	__start_bit += blocks_per_folio * btrfs_bitmap_nr_##name;	\
 	__start_bit;							\
 })
 
@@ -323,7 +329,8 @@ void btrfs_folio_end_lock_bitmap(const s
 				 struct folio *folio, unsigned long bitmap)
 {
 	struct btrfs_subpage *subpage = folio_get_private(folio);
-	const int start_bit = fs_info->sectors_per_page * btrfs_bitmap_nr_locked;
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
+	const int start_bit = blocks_per_folio * btrfs_bitmap_nr_locked;
 	unsigned long flags;
 	bool last = false;
 	int cleared = 0;
@@ -341,7 +348,7 @@ void btrfs_folio_end_lock_bitmap(const s
 	}
 
 	spin_lock_irqsave(&subpage->lock, flags);
-	for_each_set_bit(bit, &bitmap, fs_info->sectors_per_page) {
+	for_each_set_bit(bit, &bitmap, blocks_per_folio) {
 		if (test_and_clear_bit(bit + start_bit, subpage->bitmaps))
 			cleared++;
 	}
@@ -352,15 +359,27 @@ void btrfs_folio_end_lock_bitmap(const s
 		folio_unlock(folio);
 }
 
-#define subpage_test_bitmap_all_set(fs_info, subpage, name)		\
+#define subpage_test_bitmap_all_set(fs_info, folio, name)		\
+({									\
+	struct btrfs_subpage *subpage = folio_get_private(folio);	\
+	const unsigned int blocks_per_folio =				\
+				btrfs_blocks_per_folio(fs_info, folio); \
+									\
 	bitmap_test_range_all_set(subpage->bitmaps,			\
-			fs_info->sectors_per_page * btrfs_bitmap_nr_##name, \
-			fs_info->sectors_per_page)
+			blocks_per_folio * btrfs_bitmap_nr_##name,	\
+			blocks_per_folio);				\
+})
 
-#define subpage_test_bitmap_all_zero(fs_info, subpage, name)		\
+#define subpage_test_bitmap_all_zero(fs_info, folio, name)		\
+({									\
+	struct btrfs_subpage *subpage = folio_get_private(folio);	\
+	const unsigned int blocks_per_folio =				\
+				btrfs_blocks_per_folio(fs_info, folio); \
+									\
 	bitmap_test_range_all_zero(subpage->bitmaps,			\
-			fs_info->sectors_per_page * btrfs_bitmap_nr_##name, \
-			fs_info->sectors_per_page)
+			blocks_per_folio * btrfs_bitmap_nr_##name,	\
+			blocks_per_folio);				\
+})
 
 void btrfs_subpage_set_uptodate(const struct btrfs_fs_info *fs_info,
 				struct folio *folio, u64 start, u32 len)
@@ -372,7 +391,7 @@ void btrfs_subpage_set_uptodate(const st
 
 	spin_lock_irqsave(&subpage->lock, flags);
 	bitmap_set(subpage->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
-	if (subpage_test_bitmap_all_set(fs_info, subpage, uptodate))
+	if (subpage_test_bitmap_all_set(fs_info, folio, uptodate))
 		folio_mark_uptodate(folio);
 	spin_unlock_irqrestore(&subpage->lock, flags);
 }
@@ -426,7 +445,7 @@ bool btrfs_subpage_clear_and_test_dirty(
 
 	spin_lock_irqsave(&subpage->lock, flags);
 	bitmap_clear(subpage->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
-	if (subpage_test_bitmap_all_zero(fs_info, subpage, dirty))
+	if (subpage_test_bitmap_all_zero(fs_info, folio, dirty))
 		last = true;
 	spin_unlock_irqrestore(&subpage->lock, flags);
 	return last;
@@ -484,7 +503,7 @@ void btrfs_subpage_clear_writeback(const
 
 	spin_lock_irqsave(&subpage->lock, flags);
 	bitmap_clear(subpage->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
-	if (subpage_test_bitmap_all_zero(fs_info, subpage, writeback)) {
+	if (subpage_test_bitmap_all_zero(fs_info, folio, writeback)) {
 		ASSERT(folio_test_writeback(folio));
 		folio_end_writeback(folio);
 	}
@@ -515,7 +534,7 @@ void btrfs_subpage_clear_ordered(const s
 
 	spin_lock_irqsave(&subpage->lock, flags);
 	bitmap_clear(subpage->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
-	if (subpage_test_bitmap_all_zero(fs_info, subpage, ordered))
+	if (subpage_test_bitmap_all_zero(fs_info, folio, ordered))
 		folio_clear_ordered(folio);
 	spin_unlock_irqrestore(&subpage->lock, flags);
 }
@@ -530,7 +549,7 @@ void btrfs_subpage_set_checked(const str
 
 	spin_lock_irqsave(&subpage->lock, flags);
 	bitmap_set(subpage->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
-	if (subpage_test_bitmap_all_set(fs_info, subpage, checked))
+	if (subpage_test_bitmap_all_set(fs_info, folio, checked))
 		folio_set_checked(folio);
 	spin_unlock_irqrestore(&subpage->lock, flags);
 }
@@ -652,26 +671,29 @@ IMPLEMENT_BTRFS_PAGE_OPS(ordered, folio_
 IMPLEMENT_BTRFS_PAGE_OPS(checked, folio_set_checked, folio_clear_checked,
 			 folio_test_checked);
 
-#define GET_SUBPAGE_BITMAP(subpage, fs_info, name, dst)			\
+#define GET_SUBPAGE_BITMAP(fs_info, folio, name, dst)			\
 {									\
-	const int sectors_per_page = fs_info->sectors_per_page;		\
+	const unsigned int blocks_per_folio =				\
+				btrfs_blocks_per_folio(fs_info, folio);	\
+	const struct btrfs_subpage *subpage = folio_get_private(folio);	\
 									\
-	ASSERT(sectors_per_page < BITS_PER_LONG);			\
+	ASSERT(blocks_per_folio < BITS_PER_LONG);			\
 	*dst = bitmap_read(subpage->bitmaps,				\
-			   sectors_per_page * btrfs_bitmap_nr_##name,	\
-			   sectors_per_page);				\
+			   blocks_per_folio * btrfs_bitmap_nr_##name,	\
+			   blocks_per_folio);				\
 }
 
 #define SUBPAGE_DUMP_BITMAP(fs_info, folio, name, start, len)		\
 {									\
-	const struct btrfs_subpage *subpage = folio_get_private(folio);	\
 	unsigned long bitmap;						\
+	const unsigned int blocks_per_folio =				\
+				btrfs_blocks_per_folio(fs_info, folio);	\
 									\
-	GET_SUBPAGE_BITMAP(subpage, fs_info, name, &bitmap);		\
+	GET_SUBPAGE_BITMAP(fs_info, folio, name, &bitmap);		\
 	btrfs_warn(fs_info,						\
 	"dumpping bitmap start=%llu len=%u folio=%llu " #name "_bitmap=%*pbl", \
 		   start, len, folio_pos(folio),			\
-		   fs_info->sectors_per_page, &bitmap);			\
+		   blocks_per_folio, &bitmap);				\
 }
 
 /*
@@ -738,7 +760,7 @@ void btrfs_folio_set_lock(const struct b
 	}
 	bitmap_set(subpage->bitmaps, start_bit, nbits);
 	ret = atomic_add_return(nbits, &subpage->nr_locked);
-	ASSERT(ret <= fs_info->sectors_per_page);
+	ASSERT(ret <= btrfs_blocks_per_folio(fs_info, folio));
 	spin_unlock_irqrestore(&subpage->lock, flags);
 }
 
@@ -746,7 +768,7 @@ void __cold btrfs_subpage_dump_bitmap(co
 				      struct folio *folio, u64 start, u32 len)
 {
 	struct btrfs_subpage *subpage;
-	const u32 sectors_per_page = fs_info->sectors_per_page;
+	const unsigned int blocks_per_folio = btrfs_blocks_per_folio(fs_info, folio);
 	unsigned long uptodate_bitmap;
 	unsigned long dirty_bitmap;
 	unsigned long writeback_bitmap;
@@ -756,28 +778,28 @@ void __cold btrfs_subpage_dump_bitmap(co
 	unsigned long flags;
 
 	ASSERT(folio_test_private(folio) && folio_get_private(folio));
-	ASSERT(sectors_per_page > 1);
+	ASSERT(blocks_per_folio > 1);
 	subpage = folio_get_private(folio);
 
 	spin_lock_irqsave(&subpage->lock, flags);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, uptodate, &uptodate_bitmap);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, dirty, &dirty_bitmap);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, writeback, &writeback_bitmap);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, ordered, &ordered_bitmap);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, checked, &checked_bitmap);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, locked, &locked_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, uptodate, &uptodate_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, dirty, &dirty_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, writeback, &writeback_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, ordered, &ordered_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, checked, &checked_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, locked, &locked_bitmap);
 	spin_unlock_irqrestore(&subpage->lock, flags);
 
 	dump_page(folio_page(folio, 0), "btrfs subpage dump");
 	btrfs_warn(fs_info,
 "start=%llu len=%u page=%llu, bitmaps uptodate=%*pbl dirty=%*pbl locked=%*pbl writeback=%*pbl ordered=%*pbl checked=%*pbl",
 		    start, len, folio_pos(folio),
-		    sectors_per_page, &uptodate_bitmap,
-		    sectors_per_page, &dirty_bitmap,
-		    sectors_per_page, &locked_bitmap,
-		    sectors_per_page, &writeback_bitmap,
-		    sectors_per_page, &ordered_bitmap,
-		    sectors_per_page, &checked_bitmap);
+		    blocks_per_folio, &uptodate_bitmap,
+		    blocks_per_folio, &dirty_bitmap,
+		    blocks_per_folio, &locked_bitmap,
+		    blocks_per_folio, &writeback_bitmap,
+		    blocks_per_folio, &ordered_bitmap,
+		    blocks_per_folio, &checked_bitmap);
 }
 
 void btrfs_get_subpage_dirty_bitmap(struct btrfs_fs_info *fs_info,
@@ -788,10 +810,10 @@ void btrfs_get_subpage_dirty_bitmap(stru
 	unsigned long flags;
 
 	ASSERT(folio_test_private(folio) && folio_get_private(folio));
-	ASSERT(fs_info->sectors_per_page > 1);
+	ASSERT(btrfs_blocks_per_folio(fs_info, folio) > 1);
 	subpage = folio_get_private(folio);
 
 	spin_lock_irqsave(&subpage->lock, flags);
-	GET_SUBPAGE_BITMAP(subpage, fs_info, dirty, ret_bitmap);
+	GET_SUBPAGE_BITMAP(fs_info, folio, dirty, ret_bitmap);
 	spin_unlock_irqrestore(&subpage->lock, flags);
 }