ubifs: Convert do_readpage() to take a folio

All the callers now have a folio, so pass it in, and convert do_readpage()
to us folios directly.  Includes unifying the exit paths from this
function and using kmap_local instead of plain kmap.  This function
should now work with large folios, but this is not tested.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index feab95b..654af63 100644 (file)
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -96,36 +96,36 @@ dump:
        return -EINVAL;
 }
 
-static int do_readpage(struct page *page)
+static int do_readpage(struct folio *folio)
 {
        void *addr;
        int err = 0, i;
        unsigned int block, beyond;
-       struct ubifs_data_node *dn;
-       struct inode *inode = page->mapping->host;
+       struct ubifs_data_node *dn = NULL;
+       struct inode *inode = folio->mapping->host;
        struct ubifs_info *c = inode->i_sb->s_fs_info;
        loff_t i_size = i_size_read(inode);
 
        dbg_gen("ino %lu, pg %lu, i_size %lld, flags %#lx",
-               inode->i_ino, page->index, i_size, page->flags);
-       ubifs_assert(c, !PageChecked(page));
-       ubifs_assert(c, !PagePrivate(page));
+               inode->i_ino, folio->index, i_size, folio->flags);
+       ubifs_assert(c, !folio_test_checked(folio));
+       ubifs_assert(c, !folio->private);
 
-       addr = kmap(page);
+       addr = kmap_local_folio(folio, 0);
 
-       block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
+       block = folio->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
        beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
        if (block >= beyond) {
                /* Reading beyond inode */
-               SetPageChecked(page);
-               memset(addr, 0, PAGE_SIZE);
+               folio_set_checked(folio);
+               addr = folio_zero_tail(folio, 0, addr);
                goto out;
        }
 
        dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
        if (!dn) {
                err = -ENOMEM;
-               goto error;
+               goto out;
        }
 
        i = 0;
@@ -150,39 +150,35 @@ static int do_readpage(struct page *page)
                                        memset(addr + ilen, 0, dlen - ilen);
                        }
                }
-               if (++i >= UBIFS_BLOCKS_PER_PAGE)
+               if (++i >= (UBIFS_BLOCKS_PER_PAGE << folio_order(folio)))
                        break;
                block += 1;
                addr += UBIFS_BLOCK_SIZE;
+               if (folio_test_highmem(folio) && (offset_in_page(addr) == 0)) {
+                       kunmap_local(addr - UBIFS_BLOCK_SIZE);
+                       addr = kmap_local_folio(folio, i * UBIFS_BLOCK_SIZE);
+               }
        }
+
        if (err) {
                struct ubifs_info *c = inode->i_sb->s_fs_info;
                if (err == -ENOENT) {
                        /* Not found, so it must be a hole */
-                       SetPageChecked(page);
+                       folio_set_checked(folio);
                        dbg_gen("hole");
-                       goto out_free;
+                       err = 0;
+               } else {
+                       ubifs_err(c, "cannot read page %lu of inode %lu, error %d",
+                                 folio->index, inode->i_ino, err);
                }
-               ubifs_err(c, "cannot read page %lu of inode %lu, error %d",
-                         page->index, inode->i_ino, err);
-               goto error;
        }
 
-out_free:
-       kfree(dn);
 out:
-       SetPageUptodate(page);
-       ClearPageError(page);
-       flush_dcache_page(page);
-       kunmap(page);
-       return 0;
-
-error:
        kfree(dn);
-       ClearPageUptodate(page);
-       SetPageError(page);
-       flush_dcache_page(page);
-       kunmap(page);
+       if (!err)
+               folio_mark_uptodate(folio);
+       flush_dcache_folio(folio);
+       kunmap_local(addr);
        return err;
 }
 
@@ -254,7 +250,7 @@ static int write_begin_slow(struct address_space *mapping,
                if (pos == folio_pos(folio) && len >= folio_size(folio))
                        folio_set_checked(folio);
                else {
-                       err = do_readpage(&folio->page);
+                       err = do_readpage(folio);
                        if (err) {
                                folio_unlock(folio);
                                folio_put(folio);
@@ -455,7 +451,7 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
                        folio_set_checked(folio);
                        skipped_read = 1;
                } else {
-                       err = do_readpage(&folio->page);
+                       err = do_readpage(folio);
                        if (err) {
                                folio_unlock(folio);
                                folio_put(folio);
@@ -559,7 +555,7 @@ static int ubifs_write_end(struct file *file, struct address_space *mapping,
                 * Return 0 to force VFS to repeat the whole operation, or the
                 * error code if 'do_readpage()' fails.
                 */
-               copied = do_readpage(&folio->page);
+               copied = do_readpage(folio);
                goto out;
        }
 
@@ -895,7 +891,7 @@ static int ubifs_read_folio(struct file *file, struct folio *folio)
 
        if (ubifs_bulk_read(page))
                return 0;
-       do_readpage(page);
+       do_readpage(folio);
        folio_unlock(folio);
        return 0;
 }