[PATCH v2 14/18] nilfs2: convert to miscattr

[Miklos Szeredi <mszeredi@xxxxxxxxxx>]

Use the miscattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Cc: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
---
 fs/nilfs2/file.c  |  2 ++
 fs/nilfs2/ioctl.c | 61 ++++++++++++++---------------------------------
 fs/nilfs2/namei.c |  2 ++
 fs/nilfs2/nilfs.h |  3 +++
 4 files changed, 25 insertions(+), 43 deletions(-)

diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index e1bd592ce700..e2716ce4b95e 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -148,6 +148,8 @@ const struct inode_operations nilfs_file_inode_operations = {
 	.setattr	= nilfs_setattr,
 	.permission     = nilfs_permission,
 	.fiemap		= nilfs_fiemap,
+	.miscattr_get	= nilfs_miscattr_get,
+	.miscattr_set	= nilfs_miscattr_set,
 };
 
 /* end of file */
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index b053b40315bf..4bb5f09b6efa 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -16,6 +16,7 @@
 #include <linux/compat.h>	/* compat_ptr() */
 #include <linux/mount.h>	/* mnt_want_write_file(), mnt_drop_write_file() */
 #include <linux/buffer_head.h>
+#include <linux/miscattr.h>
 #include "nilfs.h"
 #include "segment.h"
 #include "bmap.h"
@@ -113,51 +114,39 @@ static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
 }
 
 /**
- * nilfs_ioctl_getflags - ioctl to support lsattr
+ * nilfs_miscattr_get - ioctl to support lsattr
  */
-static int nilfs_ioctl_getflags(struct inode *inode, void __user *argp)
+int nilfs_miscattr_get(struct dentry *dentry, struct miscattr *ma)
 {
-	unsigned int flags = NILFS_I(inode)->i_flags & FS_FL_USER_VISIBLE;
+	struct inode *inode = d_inode(dentry);
 
-	return put_user(flags, (int __user *)argp);
+	miscattr_fill_flags(ma, NILFS_I(inode)->i_flags & FS_FL_USER_VISIBLE);
+
+	return 0;
 }
 
 /**
- * nilfs_ioctl_setflags - ioctl to support chattr
+ * nilfs_miscattr_set - ioctl to support chattr
  */
-static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
-				void __user *argp)
+int nilfs_miscattr_set(struct user_namespace *mnt_userns,
+		       struct dentry *dentry, struct miscattr *ma)
 {
+	struct inode *inode = d_inode(dentry);
 	struct nilfs_transaction_info ti;
 	unsigned int flags, oldflags;
 	int ret;
 
-	if (!inode_owner_or_capable(&init_user_ns, inode))
-		return -EACCES;
-
-	if (get_user(flags, (int __user *)argp))
-		return -EFAULT;
-
-	ret = mnt_want_write_file(filp);
-	if (ret)
-		return ret;
-
-	flags = nilfs_mask_flags(inode->i_mode, flags);
-
-	inode_lock(inode);
-
-	oldflags = NILFS_I(inode)->i_flags;
+	if (miscattr_has_xattr(ma))
+		return -EOPNOTSUPP;
 
-	ret = vfs_ioc_setflags_prepare(inode, oldflags, flags);
-	if (ret)
-		goto out;
+	flags = nilfs_mask_flags(inode->i_mode, ma->flags);
 
 	ret = nilfs_transaction_begin(inode->i_sb, &ti, 0);
 	if (ret)
-		goto out;
+		return ret;
 
-	NILFS_I(inode)->i_flags = (oldflags & ~FS_FL_USER_MODIFIABLE) |
-		(flags & FS_FL_USER_MODIFIABLE);
+	oldflags = NILFS_I(inode)->i_flags & ~FS_FL_USER_MODIFIABLE;
+	NILFS_I(inode)->i_flags = oldflags | (flags & FS_FL_USER_MODIFIABLE);
 
 	nilfs_set_inode_flags(inode);
 	inode->i_ctime = current_time(inode);
@@ -165,11 +154,7 @@ static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
 		nilfs_set_transaction_flag(NILFS_TI_SYNC);
 
 	nilfs_mark_inode_dirty(inode);
-	ret = nilfs_transaction_commit(inode->i_sb);
-out:
-	inode_unlock(inode);
-	mnt_drop_write_file(filp);
-	return ret;
+	return nilfs_transaction_commit(inode->i_sb);
 }
 
 /**
@@ -1282,10 +1267,6 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	void __user *argp = (void __user *)arg;
 
 	switch (cmd) {
-	case FS_IOC_GETFLAGS:
-		return nilfs_ioctl_getflags(inode, argp);
-	case FS_IOC_SETFLAGS:
-		return nilfs_ioctl_setflags(inode, filp, argp);
 	case FS_IOC_GETVERSION:
 		return nilfs_ioctl_getversion(inode, argp);
 	case NILFS_IOCTL_CHANGE_CPMODE:
@@ -1331,12 +1312,6 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 long nilfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	switch (cmd) {
-	case FS_IOC32_GETFLAGS:
-		cmd = FS_IOC_GETFLAGS;
-		break;
-	case FS_IOC32_SETFLAGS:
-		cmd = FS_IOC_SETFLAGS;
-		break;
 	case FS_IOC32_GETVERSION:
 		cmd = FS_IOC_GETVERSION;
 		break;
diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
index ecace5f96a95..5ed4b824a8fa 100644
--- a/fs/nilfs2/namei.c
+++ b/fs/nilfs2/namei.c
@@ -552,6 +552,8 @@ const struct inode_operations nilfs_dir_inode_operations = {
 	.setattr	= nilfs_setattr,
 	.permission	= nilfs_permission,
 	.fiemap		= nilfs_fiemap,
+	.miscattr_get	= nilfs_miscattr_get,
+	.miscattr_set	= nilfs_miscattr_set,
 };
 
 const struct inode_operations nilfs_special_inode_operations = {
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index c4a45a081ade..03184ea11287 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -243,6 +243,9 @@ extern void nilfs_set_link(struct inode *, struct nilfs_dir_entry *,
 extern int nilfs_sync_file(struct file *, loff_t, loff_t, int);
 
 /* ioctl.c */
+int nilfs_miscattr_get(struct dentry *dentry, struct miscattr *m);
+int nilfs_miscattr_set(struct user_namespace *mnt_userns,
+		       struct dentry *dentry, struct miscattr *ma);
 long nilfs_ioctl(struct file *, unsigned int, unsigned long);
 long nilfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *, struct nilfs_argv *,
-- 
2.30.2