From 465e5e6a1698f3325f5d2262d2875779b06b50c7 Mon Sep 17 00:00:00 2001 From: Pankaj Raghav Date: Mon, 17 Apr 2023 14:36:15 +0200 Subject: [PATCH] fs/buffer: add folio_set_bh helper Patch series "convert create_page_buffers to folio_create_buffers". One of the first kernel panic we hit when we try to increase the block size > 4k is inside create_page_buffers()[1]. Even though buffer.c function do not support large folios (folios > PAGE_SIZE) at the moment, these changes are required when we want to remove that constraint. This patch (of 4): The folio version of set_bh_page(). This is required to convert create_page_buffers() to folio_create_buffers() later in the series. Link: https://lkml.kernel.org/r/20230417123618.22094-1-p.raghav@samsung.com Link: https://lkml.kernel.org/r/20230417123618.22094-2-p.raghav@samsung.com Signed-off-by: Pankaj Raghav Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Hannes Reinecke Cc: Alexander Viro Cc: Christian Brauner Cc: Luis Chamberlain Signed-off-by: Andrew Morton --- fs/buffer.c | 15 +++++++++++++++ include/linux/buffer_head.h | 2 ++ 2 files changed, 17 insertions(+) diff --git a/fs/buffer.c b/fs/buffer.c index 9e1e2ad..009d950 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1485,6 +1485,21 @@ void set_bh_page(struct buffer_head *bh, } EXPORT_SYMBOL(set_bh_page); +void folio_set_bh(struct buffer_head *bh, struct folio *folio, + unsigned long offset) +{ + bh->b_folio = folio; + BUG_ON(offset >= folio_size(folio)); + if (folio_test_highmem(folio)) + /* + * This catches illegal uses and preserves the offset: + */ + bh->b_data = (char *)(0 + offset); + else + bh->b_data = folio_address(folio) + offset; +} +EXPORT_SYMBOL(folio_set_bh); + /* * Called when truncating a buffer on a page completely. */ diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h index 8f14dca..7e92d23 100644 --- a/include/linux/buffer_head.h +++ b/include/linux/buffer_head.h @@ -196,6 +196,8 @@ void mark_buffer_write_io_error(struct buffer_head *bh); void touch_buffer(struct buffer_head *bh); void set_bh_page(struct buffer_head *bh, struct page *page, unsigned long offset); +void folio_set_bh(struct buffer_head *bh, struct folio *folio, + unsigned long offset); bool try_to_free_buffers(struct folio *); struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size, bool retry); -- 2.7.4