From f53bac8ddc44f155f63f5c579ce0471feef41e3a Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 19 Dec 2024 22:57:46 +0000 Subject: [PATCH] vboxsf: Convert to writepages If we add a migrate_folio operation, we can convert the writepage operation to writepages. Further, this lets us optimise by using the same write handle for multiple folios. The large folio support here is illusory; we would need to kmap each page in turn for proper support. But we do remove a few hidden calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) --- fs/vboxsf/file.c | 47 +++++++++++++++++++++++++---------------------- 1 file changed, 25 insertions(+), 22 deletions(-) diff --git a/fs/vboxsf/file.c b/fs/vboxsf/file.c index b780deb81b022..b492794f8e9a7 100644 --- a/fs/vboxsf/file.c +++ b/fs/vboxsf/file.c @@ -262,40 +262,42 @@ static struct vboxsf_handle *vboxsf_get_write_handle(struct vboxsf_inode *sf_i) return sf_handle; } -static int vboxsf_writepage(struct page *page, struct writeback_control *wbc) +static int vboxsf_writepages(struct address_space *mapping, + struct writeback_control *wbc) { - struct inode *inode = page->mapping->host; + struct inode *inode = mapping->host; + struct folio *folio = NULL; struct vboxsf_inode *sf_i = VBOXSF_I(inode); struct vboxsf_handle *sf_handle; - loff_t off = page_offset(page); loff_t size = i_size_read(inode); - u32 nwrite = PAGE_SIZE; - u8 *buf; - int err; - - if (off + PAGE_SIZE > size) - nwrite = size & ~PAGE_MASK; + int error; sf_handle = vboxsf_get_write_handle(sf_i); if (!sf_handle) return -EBADF; - buf = kmap(page); - err = vboxsf_write(sf_handle->root, sf_handle->handle, - off, &nwrite, buf); - kunmap(page); + while ((folio = writeback_iter(mapping, wbc, folio, &error))) { + loff_t off = folio_pos(folio); + u32 nwrite = folio_size(folio); + u8 *buf; - kref_put(&sf_handle->refcount, vboxsf_handle_release); + if (nwrite > size - off) + nwrite = size - off; - if (err == 0) { - /* mtime changed */ - sf_i->force_restat = 1; - } else { - ClearPageUptodate(page); + buf = kmap_local_folio(folio, 0); + error = vboxsf_write(sf_handle->root, sf_handle->handle, + off, &nwrite, buf); + kunmap_local(buf); + + folio_unlock(folio); } - unlock_page(page); - return err; + kref_put(&sf_handle->refcount, vboxsf_handle_release); + + /* mtime changed */ + if (error == 0) + sf_i->force_restat = 1; + return error; } static int vboxsf_write_end(struct file *file, struct address_space *mapping, @@ -347,10 +349,11 @@ out: */ const struct address_space_operations vboxsf_reg_aops = { .read_folio = vboxsf_read_folio, - .writepage = vboxsf_writepage, + .writepages = vboxsf_writepages, .dirty_folio = filemap_dirty_folio, .write_begin = simple_write_begin, .write_end = vboxsf_write_end, + .migrate_folio = filemap_migrate_folio, }; static const char *vboxsf_get_link(struct dentry *dentry, struct inode *inode, -- 2.50.1