From patchwork Thu Apr 25 11:37:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Pankaj Raghav (Samsung)" X-Patchwork-Id: 13643170 Received: from mout-p-201.mailbox.org (mout-p-201.mailbox.org [80.241.56.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9161512AAF8; Thu, 25 Apr 2024 11:38:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714045093; cv=none; b=Lg7vl6sBK/6dqyV0G/K3z0zREe7aGWsfHIyXvx7nSLrkbZ8Beb3tWcy5DEzOTgDynHwPOLu2xyUJu8Wmi+g7zFAdM+mI9OEFXABOSwgsiGhP5s40+NwkkBbTj2okhDEh4HvKQ0GuEKCZnuny5pgFV3Ch+FFUf6EobPh0xNuT+MY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714045093; c=relaxed/simple; bh=zmSeN/fcDsYXdQqzxDAgc9a16tTsf4MOFMr7N0Pce70=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=pI14oB+9eTu8hE7XMxinLHt8Fs6usp317kNfStZghxML23XfZfDm1K7fvh5RJuO0VJVtUnjGw5LJMWWDR81E9QSPDZXTd5T7JnjtoiQEWnP8xFWbceBHftGq8jBIgiBLhGA1uLK8X4rDRyhUg8loR+c1QilO3IKQXQMd8ObVaGo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com; spf=pass smtp.mailfrom=pankajraghav.com; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b=IbZsSndT; arc=none smtp.client-ip=80.241.56.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b="IbZsSndT" Received: from smtp202.mailbox.org (smtp202.mailbox.org [10.196.197.202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-201.mailbox.org (Postfix) with ESMTPS id 4VQDPQ5Ddmz9sq8; Thu, 25 Apr 2024 13:38:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pankajraghav.com; s=MBO0001; t=1714045082; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=T9CNQJJ+RDd4FbmtOqOiANGvF7RbcOwG9CdTM2mS7kM=; b=IbZsSndTyjSN9Xvee5cogqDuOzoH7J5rrFIQ6UKdtFgvT8kfUaS4NCsKR6pdUflcFhY+IL rdR3OapoPksLXIHK3tNiyZpOyqiEqtWGnbaswUp+WAiMm1rFPbaE5zURR9DfVAMKc++bDw 4o57Fmk7KHpUiaO2T2bLAqVgmEzDdPoI8pL2hJvt5q/tGrx7uunvyav8xgHW4Vg4WuF/e0 qTjTR04yN8FJACQx/f2zQahXWeVheOqgl5as1hKzkWgJEk7b07HGDk5I35ENUwaKwIW5fK 3jrQnR4geUlY588+NJV3eRUG/y67FNc5roYN3PobZqp1uroWXTQQySDk+MEHyA== From: "Pankaj Raghav (Samsung)" To: willy@infradead.org, djwong@kernel.org, brauner@kernel.org, david@fromorbit.com, chandan.babu@oracle.com, akpm@linux-foundation.org Cc: linux-fsdevel@vger.kernel.org, hare@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-xfs@vger.kernel.org, mcgrof@kernel.org, gost.dev@samsung.com, p.raghav@samsung.com Subject: [PATCH v4 03/11] filemap: allocate mapping_min_order folios in the page cache Date: Thu, 25 Apr 2024 13:37:38 +0200 Message-Id: <20240425113746.335530-4-kernel@pankajraghav.com> In-Reply-To: <20240425113746.335530-1-kernel@pankajraghav.com> References: <20240425113746.335530-1-kernel@pankajraghav.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Luis Chamberlain filemap_create_folio() and do_read_cache_folio() were always allocating folio of order 0. __filemap_get_folio was trying to allocate higher order folios when fgp_flags had higher order hint set but it will default to order 0 folio if higher order memory allocation fails. Supporting mapping_min_order implies that we guarantee each folio in the page cache has at least an order of mapping_min_order. When adding new folios to the page cache we must also ensure the index used is aligned to the mapping_min_order as the page cache requires the index to be aligned to the order of the folio. Signed-off-by: Luis Chamberlain Co-developed-by: Pankaj Raghav Signed-off-by: Pankaj Raghav Reviewed-by: Hannes Reinecke Reviewed-by: Darrick J. Wong --- mm/filemap.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 30de18c4fd28..f0c0cfbbd134 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -858,6 +858,8 @@ noinline int __filemap_add_folio(struct address_space *mapping, VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); VM_BUG_ON_FOLIO(folio_test_swapbacked(folio), folio); + VM_BUG_ON_FOLIO(folio_order(folio) < mapping_min_folio_order(mapping), + folio); mapping_set_update(&xas, mapping); if (!huge) { @@ -1895,8 +1897,10 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, folio_wait_stable(folio); no_page: if (!folio && (fgp_flags & FGP_CREAT)) { - unsigned order = FGF_GET_ORDER(fgp_flags); + unsigned int min_order = mapping_min_folio_order(mapping); + unsigned int order = max(min_order, FGF_GET_ORDER(fgp_flags)); int err; + index = mapping_align_start_index(mapping, index); if ((fgp_flags & FGP_WRITE) && mapping_can_writeback(mapping)) gfp |= __GFP_WRITE; @@ -1936,7 +1940,7 @@ struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, break; folio_put(folio); folio = NULL; - } while (order-- > 0); + } while (order-- > min_order); if (err == -EEXIST) goto repeat; @@ -2425,13 +2429,16 @@ static int filemap_update_page(struct kiocb *iocb, } static int filemap_create_folio(struct file *file, - struct address_space *mapping, pgoff_t index, + struct address_space *mapping, loff_t pos, struct folio_batch *fbatch) { struct folio *folio; int error; + unsigned int min_order = mapping_min_folio_order(mapping); + pgoff_t index; - folio = filemap_alloc_folio(mapping_gfp_mask(mapping), 0); + folio = filemap_alloc_folio(mapping_gfp_mask(mapping), + min_order); if (!folio) return -ENOMEM; @@ -2449,6 +2456,8 @@ static int filemap_create_folio(struct file *file, * well to keep locking rules simple. */ filemap_invalidate_lock_shared(mapping); + /* index in PAGE units but aligned to min_order number of pages. */ + index = (pos >> (PAGE_SHIFT + min_order)) << min_order; error = filemap_add_folio(mapping, folio, index, mapping_gfp_constraint(mapping, GFP_KERNEL)); if (error == -EEXIST) @@ -2509,8 +2518,7 @@ static int filemap_get_pages(struct kiocb *iocb, size_t count, if (!folio_batch_count(fbatch)) { if (iocb->ki_flags & (IOCB_NOWAIT | IOCB_WAITQ)) return -EAGAIN; - err = filemap_create_folio(filp, mapping, - iocb->ki_pos >> PAGE_SHIFT, fbatch); + err = filemap_create_folio(filp, mapping, iocb->ki_pos, fbatch); if (err == AOP_TRUNCATED_PAGE) goto retry; return err; @@ -3708,9 +3716,11 @@ static struct folio *do_read_cache_folio(struct address_space *mapping, repeat: folio = filemap_get_folio(mapping, index); if (IS_ERR(folio)) { - folio = filemap_alloc_folio(gfp, 0); + folio = filemap_alloc_folio(gfp, + mapping_min_folio_order(mapping)); if (!folio) return ERR_PTR(-ENOMEM); + index = mapping_align_start_index(mapping, index); err = filemap_add_folio(mapping, folio, index, gfp); if (unlikely(err)) { folio_put(folio);