From nobody Tue Oct 22 22:22:11 2024 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C921BC77B7A for ; Fri, 26 May 2023 07:56:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242316AbjEZH4k (ORCPT ); Fri, 26 May 2023 03:56:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242593AbjEZH4L (ORCPT ); Fri, 26 May 2023 03:56:11 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68C721AC; Fri, 26 May 2023 00:56:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=psFng5IfKHz74jJHGQgHSSVFQ4pTJ14DfYwhK5NX3MQ=; b=xoH7UfNZuu4OOweZByfPFv0uQr AQbwg9ANaqY/qhG0wv6sLOxmNdkdtZ1pWBLCLLQSCJrCn7nP4ulbiXcVnfDtSVP0xLq1RGiysiMfP +hdw95L0XG5Z04NUiSJeSHYt2DX66Fu3FzfwjSUUF5NWBjS6sf61hOrpd79KQksg+YzjQOt4BN9XT y8n7ybw+BpRD1A502saPw5AwElzRrYe3QdibOCuYi66zgi4bTzSIqK4flERKfti2wxO6AJC7ybQv7 ZGZlcQJcDyVwuR+KnRkZjkBlFZ8gZQkwZhMfEUPoAtsqUOw7oW1U0Nv0LI44ED0adAn1Az1C2Fw1X TInKM54w==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.96 #2 (Red Hat Linux)) id 1q2SIk-001Wa1-0B; Fri, 26 May 2023 07:55:54 +0000 From: Luis Chamberlain To: hughd@google.com, akpm@linux-foundation.org, willy@infradead.org, brauner@kernel.org, djwong@kernel.org Cc: p.raghav@samsung.com, da.gomez@samsung.com, rohan.puri@samsung.com, rpuri.linux@gmail.com, a.manzanares@samsung.com, dave@stgolabs.net, yosryahmed@google.com, keescook@chromium.org, hare@suse.de, kbusch@kernel.org, mcgrof@kernel.org, patches@lists.linux.dev, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [RFC v2 8/8] shmem: add support to customize block size order Date: Fri, 26 May 2023 00:55:52 -0700 Message-Id: <20230526075552.363524-9-mcgrof@kernel.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20230526075552.363524-1-mcgrof@kernel.org> References: <20230526075552.363524-1-mcgrof@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: Luis Chamberlain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This allows tmpfs mounts to use a custom block size order. We only allow block sizes greater than PAGE_SIZE, and these must also be a multiple of the PAGE_SIZE too. To simplify these requirements and the math we just use power of 2 order, so block order. Only simple tests have been run so far: mkdir -p /data-tmpfs/ time for i in $(seq 1 1000000); do echo $i >> /root/ordered.txt; done real 0m21.392s user 0m8.077s sys 0m13.098s du -h /root/ordered.txt 6.6M /root/ordered.txt sha1sum /root/ordered.txt 2dcc06b7ca3b7dd8b5626af83c1be3cb08ddc76c /root/ordered.txt stat /root/ordered.txt File: /root/ordered.txt Size: 6888896 Blocks: 13456 IO Block: 4096 regular file Device: 254,1 Inode: 655717 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2023-04-21 19:34:20.709869093 +0000 Modify: 2023-04-21 19:34:43.833900042 +0000 Change: 2023-04-21 19:34:43.833900042 +0000 Birth: 2023-04-21 19:34:20.709869093 +0000 8 KiB block size: sha1sum /root/ordered.txt mount -t tmpfs -o size=3D10M,border=3D13 -o noswap tmpfs /data-t= mpfs/ cp /root/ordered.txt sha1sum /data-tmpfs/ordered.txt stat /data-tmpfs/ordered.txt 2dcc06b7ca3b7dd8b5626af83c1be3cb08ddc76c /root/ordered.txt 2dcc06b7ca3b7dd8b5626af83c1be3cb08ddc76c /data-tmpfs/ordered.txt File: /data-tmpfs/ordered.txt Size: 6888896 Blocks: 13456 IO Block: 8192 regular file Device: 0,42 Inode: 2 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2023-04-21 19:31:16.078390405 +0000 Modify: 2023-04-21 19:31:16.070391363 +0000 Change: 2023-04-21 19:31:16.070391363 +0000 Birth: 2023-04-21 19:31:16.034395676 +0000 64 KiB block size: sha1sum /root/ordered.txt mount -t tmpfs -o size=3D10M,border=3D16 -o noswap tmpfs /data-t= mpfs/ cp /root/ordered.txt /data-tmpfs/; sha1sum /data-tmpfs/ordered.txt stat /data-tmpfs/ordered.txt 2dcc06b7ca3b7dd8b5626af83c1be3cb08ddc76c /root/ordered.txt 2dcc06b7ca3b7dd8b5626af83c1be3cb08ddc76c /data-tmpfs/ordered.txt File: /data-tmpfs/ordered.txt Size: 6888896 Blocks: 13568 IO Block: 65536 regular file Device: 0,42 Inode: 2 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Access: 2023-04-21 19:32:14.669796970 +0000 Modify: 2023-04-21 19:32:14.661796959 +0000 Change: 2023-04-21 19:32:14.661796959 +0000 Birth: 2023-04-21 19:32:14.649796944 +0000 4 MiB works too. Signed-off-by: Luis Chamberlain --- mm/shmem.c | 44 +++++++++++++++++++++++++++++++++++++++----- 1 file changed, 39 insertions(+), 5 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 080864949fe5..777e953df62e 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -115,11 +115,13 @@ struct shmem_options { int huge; int seen; bool noswap; + unsigned char block_order; #define SHMEM_SEEN_BLOCKS 1 #define SHMEM_SEEN_INODES 2 #define SHMEM_SEEN_HUGE 4 #define SHMEM_SEEN_INUMS 8 #define SHMEM_SEEN_NOSWAP 16 +#define SHMEM_SEEN_BLOCKORDER 32 }; =20 static u64 shmem_default_block_order(void) @@ -3661,6 +3663,7 @@ enum shmem_param { Opt_inode32, Opt_inode64, Opt_noswap, + Opt_border, }; =20 static const struct constant_table shmem_param_enums_huge[] =3D { @@ -3683,6 +3686,7 @@ const struct fs_parameter_spec shmem_fs_parameters[] = =3D { fsparam_flag ("inode32", Opt_inode32), fsparam_flag ("inode64", Opt_inode64), fsparam_flag ("noswap", Opt_noswap), + fsparam_u32 ("border", Opt_border), {} }; =20 @@ -3709,7 +3713,15 @@ static int shmem_parse_one(struct fs_context *fc, st= ruct fs_parameter *param) } if (*rest) goto bad_value; - ctx->blocks =3D DIV_ROUND_UP(size, PAGE_SIZE); + if (!(ctx->seen & SHMEM_SEEN_BLOCKORDER) || + ctx->block_order =3D=3D shmem_default_block_order()) + ctx->blocks =3D DIV_ROUND_UP(size, PAGE_SIZE); + else { + if (size < (1UL << ctx->block_order) || + size % (1UL << ctx->block_order) !=3D 0) + goto bad_value; + ctx->blocks =3D size >> ctx->block_order; + } ctx->seen |=3D SHMEM_SEEN_BLOCKS; break; case Opt_nr_blocks: @@ -3774,6 +3786,19 @@ static int shmem_parse_one(struct fs_context *fc, st= ruct fs_parameter *param) ctx->noswap =3D true; ctx->seen |=3D SHMEM_SEEN_NOSWAP; break; + case Opt_border: + ctx->block_order =3D result.uint_32; + ctx->seen |=3D SHMEM_SEEN_BLOCKORDER; + if (ctx->block_order < PAGE_SHIFT) + goto bad_value; + /* + * We cap this to allow a block to be at least allowed to + * be allocated using the buddy allocator. That's MAX_ORDER + * pages. So 8 MiB on x86_64. + */ + if (ctx->block_order > (MAX_ORDER + PAGE_SHIFT)) + goto bad_value; + break; } return 0; =20 @@ -3845,6 +3870,12 @@ static int shmem_reconfigure(struct fs_context *fc) raw_spin_lock(&sbinfo->stat_lock); inodes =3D sbinfo->max_inodes - sbinfo->free_inodes; =20 + if (ctx->seen & SHMEM_SEEN_BLOCKORDER) { + if (ctx->block_order !=3D shmem_block_order(sbinfo)) { + err =3D "Cannot modify block order on remount"; + goto out; + } + } if ((ctx->seen & SHMEM_SEEN_BLOCKS) && ctx->blocks) { if (!sbinfo->max_blocks) { err =3D "Cannot retroactively limit size"; @@ -3960,6 +3991,8 @@ static int shmem_show_options(struct seq_file *seq, s= truct dentry *root) shmem_show_mpol(seq, sbinfo->mpol); if (sbinfo->noswap) seq_printf(seq, ",noswap"); + if (shmem_block_order(sbinfo) !=3D shmem_default_block_order()) + seq_printf(seq, ",border=3D%llu", shmem_block_order(sbinfo)); return 0; } =20 @@ -3997,10 +4030,12 @@ static int shmem_fill_super(struct super_block *sb,= struct fs_context *fc) * but the internal instance is left unlimited. */ if (!(sb->s_flags & SB_KERNMOUNT)) { + if (!(ctx->seen & SHMEM_SEEN_BLOCKORDER)) + ctx->block_order =3D shmem_default_block_order(); if (!(ctx->seen & SHMEM_SEEN_BLOCKS)) - ctx->blocks =3D shmem_default_max_blocks(shmem_default_block_order()); + ctx->blocks =3D shmem_default_max_blocks(ctx->block_order); if (!(ctx->seen & SHMEM_SEEN_INODES)) - ctx->inodes =3D shmem_default_max_inodes(shmem_default_block_order()); + ctx->inodes =3D shmem_default_max_inodes(ctx->block_order); if (!(ctx->seen & SHMEM_SEEN_INUMS)) ctx->full_inums =3D IS_ENABLED(CONFIG_TMPFS_INODE64); sbinfo->noswap =3D ctx->noswap; @@ -4009,7 +4044,7 @@ static int shmem_fill_super(struct super_block *sb, s= truct fs_context *fc) } sb->s_export_op =3D &shmem_export_ops; sb->s_flags |=3D SB_NOSEC | SB_I_VERSION; - sbinfo->block_order =3D shmem_default_block_order(); + sbinfo->block_order =3D ctx->block_order; #else sb->s_flags |=3D SB_NOUSER; #endif @@ -4037,7 +4072,6 @@ static int shmem_fill_super(struct super_block *sb, s= truct fs_context *fc) sb->s_maxbytes =3D MAX_LFS_FILESIZE; sb->s_blocksize =3D shmem_sb_blocksize(sbinfo); sb->s_blocksize_bits =3D shmem_block_order(sbinfo); - WARN_ON_ONCE(sb->s_blocksize_bits !=3D PAGE_SHIFT); sb->s_magic =3D TMPFS_MAGIC; sb->s_op =3D &shmem_ops; sb->s_time_gran =3D 1; --=20 2.39.2