Lukas Czerner <lczerner@xxxxxxxxxx> writes:
> Adds an filesystem independent ioctl to allow implementation of file
> system batched discard support.
>
> Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
> ---
> 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.
> +{
> + 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@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
