From patchwork Mon Sep 27 14:09:58 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Czerner X-Patchwork-Id: 65862 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C9C8CB6F06 for ; Tue, 28 Sep 2010 00:10:40 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757692Ab0I0OKS (ORCPT ); Mon, 27 Sep 2010 10:10:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44688 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755984Ab0I0OKQ (ORCPT ); Mon, 27 Sep 2010 10:10:16 -0400 Received: from int-mx08.intmail.prod.int.phx2.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o8REAE8b030005 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 27 Sep 2010 10:10:14 -0400 Received: from dhcp-lab-213.englab.brq.redhat.com (dhcp-27-236.brq.redhat.com [10.34.27.236]) by int-mx08.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o8REA8D8006505; Mon, 27 Sep 2010 10:10:12 -0400 From: Lukas Czerner To: linux-ext4@vger.kernel.org Cc: tytso@mit.edu, rwheeler@redhat.com, sandeen@redhat.com, adilger@dilger.ca, lczerner@redhat.com Subject: [PATCH 2/4] Add ioctl FITRIM. Date: Mon, 27 Sep 2010 16:09:58 +0200 Message-Id: <1285596600-28358-3-git-send-email-lczerner@redhat.com> In-Reply-To: <1285596600-28358-1-git-send-email-lczerner@redhat.com> References: <1285596600-28358-1-git-send-email-lczerner@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.21 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Adds an filesystem independent ioctl to allow implementation of file system batched discard support. I takes fstrim_range structure as an argument. fstrim_range is definec in the include/fs.h and its definition is as follows. struct fstrim_range { start; len; minlen; } start - first Byte to trim len - number of Bytes to trim from start minlen - minimum extent length to trim, free extents shorter than this number of Bytes will be ignored. This will be rounded up to fs block size. It is also possible to specify NULL as an argument. In this case the arguments will set itself as follows: start = 0; len = ULLONG_MAX; minlen = 0; So it will trim the whole file system at one run. After the FITRIM is done, the number of actually discarded Bytes is stored in fstrim_range.len to give the user better insight on how much storage space has been really released for wear-leveling. Signed-off-by: Lukas Czerner Reviewed-by: Dmitry Monakhov --- fs/ioctl.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 8 ++++++++ 2 files changed, 47 insertions(+), 0 deletions(-) diff --git a/fs/ioctl.c b/fs/ioctl.c index f855ea4..e92fdbb 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -530,6 +530,41 @@ static int ioctl_fsthaw(struct file *filp) return thaw_super(sb); } +static int ioctl_fstrim(struct file *filp, void __user *argp) +{ + struct super_block *sb = filp->f_path.dentry->d_inode->i_sb; + struct fstrim_range range; + int ret = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* If filesystem doesn't support trim feature, return. */ + if (sb->s_op->trim_fs == NULL) + return -EOPNOTSUPP; + + /* If a blockdevice-backed filesystem isn't specified, return EINVAL. */ + if (sb->s_bdev == NULL) + return -EINVAL; + + if (argp == NULL) { + range.start = 0; + range.len = ULLONG_MAX; + range.minlen = 0; + } else if (copy_from_user(&range, argp, sizeof(range))) + return -EFAULT; + + ret = sb->s_op->trim_fs(sb, &range); + if (ret < 0) + return ret; + + if ((argp != NULL) && + (copy_to_user(argp, &range, sizeof(range)))) + return -EFAULT; + + return 0; +} + /* * When you add any new common ioctls to the switches above and below * please update compat_sys_ioctl() too. @@ -580,6 +615,10 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, error = ioctl_fsthaw(filp); break; + case FITRIM: + error = ioctl_fstrim(filp, argp); + break; + case FS_IOC_FIEMAP: return ioctl_fiemap(filp, arg); diff --git a/include/linux/fs.h b/include/linux/fs.h index 0ec4d60e..63a0843 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -32,6 +32,12 @@ #define SEEK_END 2 /* seek relative to end of file */ #define SEEK_MAX SEEK_END +struct fstrim_range { + uint64_t start; + uint64_t len; + uint64_t minlen; +}; + /* And dynamically-tunable limits and defaults: */ struct files_stat_struct { int nr_files; /* read only */ @@ -312,6 +318,7 @@ struct inodes_stat_t { #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */ #define FIFREEZE _IOWR('X', 119, int) /* Freeze */ #define FITHAW _IOWR('X', 120, int) /* Thaw */ +#define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */ #define FS_IOC_GETFLAGS _IOR('f', 1, long) #define FS_IOC_SETFLAGS _IOW('f', 2, long) @@ -1573,6 +1580,7 @@ struct super_operations { ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); #endif int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t); + int (*trim_fs) (struct super_block *, struct fstrim_range *); }; /*