Jeff Liu
2012-Dec-12 03:22 UTC
[RESEND PATCH V4 1/2] Btrfs: Add a new ioctl to get the label of a mounted filesystem
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
fs/btrfs/ioctl.c | 14 ++++++++++++++
fs/btrfs/ioctl.h | 2 ++
2 files changed, 16 insertions(+)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 8fcf9a5..b0a5e17 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3699,6 +3699,18 @@ out:
return ret;
}
+static int btrfs_ioctl_get_fslabel(struct btrfs_root *root, void __user *arg)
+{
+ const char *label = root->fs_info->super_copy->label;
+ int ret;
+
+ mutex_lock(&root->fs_info->volume_mutex);
+ ret = copy_to_user(arg, label, strlen(label));
+ mutex_unlock(&root->fs_info->volume_mutex);
+
+ return ret ? -EFAULT : 0;
+}
+
long btrfs_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
{
@@ -3797,6 +3809,8 @@ long btrfs_ioctl(struct file *file, unsigned int
return btrfs_ioctl_qgroup_create(root, argp);
case BTRFS_IOC_QGROUP_LIMIT:
return btrfs_ioctl_qgroup_limit(root, argp);
+ case BTRFS_IOC_GET_FSLABEL:
+ return btrfs_ioctl_get_fslabel(root, argp);
}
return -ENOTTY;
diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h
index 731e287..98f896f 100644
--- a/fs/btrfs/ioctl.h
+++ b/fs/btrfs/ioctl.h
@@ -453,4 +453,6 @@ struct btrfs_ioctl_send_args {
struct btrfs_ioctl_qgroup_limit_args)
#define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \
struct btrfs_ioctl_get_dev_stats)
+#define BTRFS_IOC_GET_FSLABEL _IOR(BTRFS_IOCTL_MAGIC, 53, \
+ char[BTRFS_LABEL_SIZE])
#endif
--
1.7.9.5
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Miao Xie
2012-Dec-12 03:50 UTC
Re: [RESEND PATCH V4 1/2] Btrfs: Add a new ioctl to get the label of a mounted filesystem
On Wed, 12 Dec 2012 11:22:49 +0800, Jeff Liu wrote:> Signed-off-by: Jie Liu <jeff.liu@oracle.com> > Signed-off-by: Anand Jain <anand.jain@oracle.com> > > --- > fs/btrfs/ioctl.c | 14 ++++++++++++++ > fs/btrfs/ioctl.h | 2 ++ > 2 files changed, 16 insertions(+) > > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index 8fcf9a5..b0a5e17 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -3699,6 +3699,18 @@ out: > return ret; > } > > +static int btrfs_ioctl_get_fslabel(struct btrfs_root *root, void __user *arg) > +{ > + const char *label = root->fs_info->super_copy->label; > + int ret; > + > + mutex_lock(&root->fs_info->volume_mutex); > + ret = copy_to_user(arg, label, strlen(label)); > + mutex_unlock(&root->fs_info->volume_mutex); > + > + return ret ? -EFAULT : 0; > +} > + > long btrfs_ioctl(struct file *file, unsigned int > cmd, unsigned long arg) > { > @@ -3797,6 +3809,8 @@ long btrfs_ioctl(struct file *file, unsigned int > return btrfs_ioctl_qgroup_create(root, argp); > case BTRFS_IOC_QGROUP_LIMIT: > return btrfs_ioctl_qgroup_limit(root, argp); > + case BTRFS_IOC_GET_FSLABEL: > + return btrfs_ioctl_get_fslabel(root, argp); > } > > return -ENOTTY; > diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h > index 731e287..98f896f 100644 > --- a/fs/btrfs/ioctl.h > +++ b/fs/btrfs/ioctl.h > @@ -453,4 +453,6 @@ struct btrfs_ioctl_send_args { > struct btrfs_ioctl_qgroup_limit_args) > #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ > struct btrfs_ioctl_get_dev_stats) > +#define BTRFS_IOC_GET_FSLABEL _IOR(BTRFS_IOCTL_MAGIC, 53, \ > + char[BTRFS_LABEL_SIZE]) > #endif >According to the project idea web, https://btrfs.wiki.kernel.org/index.php/Project_ideas#Development_notes.2C_please_read number 53 has been used for the drive swapping commands, so I think we should choose another one. Maybe 49 is good since the above web says number 50 has been reserved for set/change label command. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Jeff Liu
2012-Dec-12 04:01 UTC
Re: [RESEND PATCH V4 1/2] Btrfs: Add a new ioctl to get the label of a mounted filesystem
On 12/12/2012 11:50 AM, Miao Xie wrote:> On Wed, 12 Dec 2012 11:22:49 +0800, Jeff Liu wrote: >> Signed-off-by: Jie Liu <jeff.liu@oracle.com> >> Signed-off-by: Anand Jain <anand.jain@oracle.com> >> >> --- >> fs/btrfs/ioctl.c | 14 ++++++++++++++ >> fs/btrfs/ioctl.h | 2 ++ >> 2 files changed, 16 insertions(+) >> >> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c >> index 8fcf9a5..b0a5e17 100644 >> --- a/fs/btrfs/ioctl.c >> +++ b/fs/btrfs/ioctl.c >> @@ -3699,6 +3699,18 @@ out: >> return ret; >> } >> >> +static int btrfs_ioctl_get_fslabel(struct btrfs_root *root, void __user *arg) >> +{ >> + const char *label = root->fs_info->super_copy->label; >> + int ret; >> + >> + mutex_lock(&root->fs_info->volume_mutex); >> + ret = copy_to_user(arg, label, strlen(label)); >> + mutex_unlock(&root->fs_info->volume_mutex); >> + >> + return ret ? -EFAULT : 0; >> +} >> + >> long btrfs_ioctl(struct file *file, unsigned int >> cmd, unsigned long arg) >> { >> @@ -3797,6 +3809,8 @@ long btrfs_ioctl(struct file *file, unsigned int >> return btrfs_ioctl_qgroup_create(root, argp); >> case BTRFS_IOC_QGROUP_LIMIT: >> return btrfs_ioctl_qgroup_limit(root, argp); >> + case BTRFS_IOC_GET_FSLABEL: >> + return btrfs_ioctl_get_fslabel(root, argp); >> } >> >> return -ENOTTY; >> diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h >> index 731e287..98f896f 100644 >> --- a/fs/btrfs/ioctl.h >> +++ b/fs/btrfs/ioctl.h >> @@ -453,4 +453,6 @@ struct btrfs_ioctl_send_args { >> struct btrfs_ioctl_qgroup_limit_args) >> #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ >> struct btrfs_ioctl_get_dev_stats) >> +#define BTRFS_IOC_GET_FSLABEL _IOR(BTRFS_IOCTL_MAGIC, 53, \ >> + char[BTRFS_LABEL_SIZE]) >> #endif >> > > According to the project idea web, > https://btrfs.wiki.kernel.org/index.php/Project_ideas#Development_notes.2C_please_read > > number 53 has been used for the drive swapping commands, so I think we should > choose another one. Maybe 49 is good since the above web says number 50 has been > reserved for set/change label command.Ok, let''s waiting for others comments, I''ll follow up the final confirmation. Thanks, -Jeff> -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html