ext4: Use a folio in ext4_da_write_begin()

Remove a few calls to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20230324180129.1220691-23-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index bf1a19c09b5d205a2a2ffab6a962f06cf6ac1fa1..9e8afac5c82e15f8d33057315e36398261e4964c 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2902,7 +2902,7 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
                               struct page **pagep, void **fsdata)
 {
        int ret, retries = 0;
-       struct page *page;
+       struct folio *folio;
        pgoff_t index;
        struct inode *inode = mapping->host;
 
@@ -2929,22 +2929,23 @@ static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
        }
 
 retry:
-       page = grab_cache_page_write_begin(mapping, index);
-       if (!page)
+       folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
+                       mapping_gfp_mask(mapping));
+       if (!folio)
                return -ENOMEM;
 
-       /* In case writeback began while the page was unlocked */
-       wait_for_stable_page(page);
+       /* In case writeback began while the folio was unlocked */
+       folio_wait_stable(folio);
 
 #ifdef CONFIG_FS_ENCRYPTION
-       ret = ext4_block_write_begin(page, pos, len,
+       ret = ext4_block_write_begin(&folio->page, pos, len,
                                     ext4_da_get_block_prep);
 #else
-       ret = __block_write_begin(page, pos, len, ext4_da_get_block_prep);
+       ret = __block_write_begin(&folio->page, pos, len, ext4_da_get_block_prep);
 #endif
        if (ret < 0) {
-               unlock_page(page);
-               put_page(page);
+               folio_unlock(folio);
+               folio_put(folio);
                /*
                 * block_write_begin may have instantiated a few blocks
                 * outside i_size.  Trim these off again. Don't need
@@ -2959,7 +2960,7 @@ retry:
                return ret;
        }
 
-       *pagep = page;
+       *pagep = &folio->page;
        return ret;
 }