From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukas Czerner Subject: Re: [PATCH 1/3] Add ioctl FITRIM. Date: Wed, 4 Aug 2010 17:13:01 +0200 (CEST) Message-ID: References: <1280929475-12823-1-git-send-email-lczerner@redhat.com> <8762zq8lxv.fsf@dmon-lap.sw.ru> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Lukas Czerner , linux-ext4@vger.kernel.org, jmoyer@redhat.com, rwheeler@redhat.com, eshishki@redhat.com, sandeen@redhat.com, jack@suse.cz, tytso@mit.edu To: Dmitry Monakhov Return-path: Received: from mx1.redhat.com ([209.132.183.28]:39158 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752711Ab0HDPNK (ORCPT ); Wed, 4 Aug 2010 11:13:10 -0400 In-Reply-To: <8762zq8lxv.fsf@dmon-lap.sw.ru> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, 4 Aug 2010, Dmitry Monakhov wrote: > Lukas Czerner writes: > > > Adds an filesystem independent ioctl to allow implementation of file > > system batched discard support. > > > > Signed-off-by: Lukas Czerner > > --- > > fs/ioctl.c | 31 +++++++++++++++++++++++++++++++ > > include/linux/fs.h | 2 ++ > > 2 files changed, 33 insertions(+), 0 deletions(-) > > > > diff --git a/fs/ioctl.c b/fs/ioctl.c > > index 2d140a7..6c01c3c 100644 > > --- a/fs/ioctl.c > > +++ b/fs/ioctl.c > > @@ -540,6 +540,33 @@ static int ioctl_fsthaw(struct file *filp) > > return thaw_super(sb); > > } > > > > +static int ioctl_fstrim(struct file *filp, unsigned long arg) > BTW why do we have to trim fs in one shot ? > IMHO it is much suitable to provide start,len parameters as we > do in most functions(truncate, bdevdiscard, getdents). > It allow userspace caller to implement a fancy looking progress bars. Hi, do you think it is really needed when even with todays SSD's it takes just a couple of seconds ? And I suppose it will improve in future. But generally I think we can do that..I would like to hear some more opinions before I start looking at this. Thanks. -Lukas. > > +{ > > + struct super_block *sb = filp->f_path.dentry->d_inode->i_sb; > > + unsigned int minlen; > > + int err; > > + > > + 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; > > + > > + err = get_user(minlen, (unsigned int __user *) arg); > > + if (err) > > + return err; > > + > > + err = sb->s_op->trim_fs(minlen, sb); > > + if (err) > > + return err; > > + return 0; > > +} > > + > > /* > > * When you add any new common ioctls to the switches above and below > > * please update compat_sys_ioctl() too. > > @@ -590,6 +617,10 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, > > error = ioctl_fsthaw(filp); > > break; > > > > + case FITRIM: > > + error = ioctl_fstrim(filp, arg); > > + break; > > + > > case FS_IOC_FIEMAP: > > return ioctl_fiemap(filp, arg); > > > > diff --git a/include/linux/fs.h b/include/linux/fs.h > > index 68ca1b0..01632e4 100644 > > --- a/include/linux/fs.h > > +++ b/include/linux/fs.h > > @@ -315,6 +315,7 @@ 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, int) /* Trim */ > > > > #define FS_IOC_GETFLAGS _IOR('f', 1, long) > > #define FS_IOC_SETFLAGS _IOW('f', 2, long) > > @@ -1580,6 +1581,7 @@ 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) (unsigned int, struct super_block *); > > }; > > > > /* > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >