buffer: replace obvious uses of b_page with b_folio

These cases just check if it's NULL, or use b_page to get to the page's
address space.  They are assumptions that b_page never points to a tail
page.

Link: https://lkml.kernel.org/r/20221215214402.3522366-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/buffer.c b/fs/buffer.c
index d9c6d1f..e1055fe 100644 (file)
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -321,7 +321,7 @@ static void end_buffer_async_read_io(struct buffer_head *bh, int uptodate)
 {
        /* Decrypt if needed */
        if (uptodate &&
-           fscrypt_inode_uses_fs_layer_crypto(bh->b_page->mapping->host)) {
+           fscrypt_inode_uses_fs_layer_crypto(bh->b_folio->mapping->host)) {
                struct decrypt_bh_ctx *ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
 
                if (ctx) {
@@ -570,7 +570,7 @@ void write_boundary_block(struct block_device *bdev,
 void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode)
 {
        struct address_space *mapping = inode->i_mapping;
-       struct address_space *buffer_mapping = bh->b_page->mapping;
+       struct address_space *buffer_mapping = bh->b_folio->mapping;
 
        mark_buffer_dirty(bh);
        if (!mapping->private_data) {
@@ -1073,7 +1073,7 @@ __getblk_slow(struct block_device *bdev, sector_t block,
  * and then attach the address_space's inode to its superblock's dirty
  * inode list.
  *
- * mark_buffer_dirty() is atomic.  It takes bh->b_page->mapping->private_lock,
+ * mark_buffer_dirty() is atomic.  It takes bh->b_folio->mapping->private_lock,
  * i_pages lock and mapping->host->i_lock.
  */
 void mark_buffer_dirty(struct buffer_head *bh)
@@ -1117,8 +1117,8 @@ void mark_buffer_write_io_error(struct buffer_head *bh)
 
        set_buffer_write_io_error(bh);
        /* FIXME: do we need to set this in both places? */
-       if (bh->b_page && bh->b_page->mapping)
-               mapping_set_error(bh->b_page->mapping, -EIO);
+       if (bh->b_folio && bh->b_folio->mapping)
+               mapping_set_error(bh->b_folio->mapping, -EIO);
        if (bh->b_assoc_map)
                mapping_set_error(bh->b_assoc_map, -EIO);
        rcu_read_lock();
@@ -1154,7 +1154,7 @@ void __bforget(struct buffer_head *bh)
 {
        clear_buffer_dirty(bh);
        if (bh->b_assoc_map) {
-               struct address_space *buffer_mapping = bh->b_page->mapping;
+               struct address_space *buffer_mapping = bh->b_folio->mapping;
 
                spin_lock(&buffer_mapping->private_lock);
                list_del_init(&bh->b_assoc_buffers);