On 4/12/2018 8:38 PM, Miklos Szeredi wrote:
Implement FS_IOC_GETFLAGS and FS_IOC_SETFLAGS.
Needs vfs_ioctl() exported to modules.
Do you think if it is better to separate out ovl implementation and
export of vfs_ioctl method ?
Probably there are other users which should be using vfs_ioctl method as
well (like ecryptfs) ?
Signed-off-by: Miklos Szeredi <mszer...@redhat.com>
---
fs/internal.h | 1 -
fs/ioctl.c | 1 +
fs/overlayfs/file.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/fs.h | 2 ++
4 files changed, 62 insertions(+), 1 deletion(-)
diff --git a/fs/internal.h b/fs/internal.h
index 3319bf39e339..d5108d9c6a2f 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -176,7 +176,6 @@ extern const struct dentry_operations ns_dentry_operations;
*/
extern int do_vfs_ioctl(struct file *file, unsigned int fd, unsigned int cmd,
unsigned long arg);
-extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
/*
* iomap support:
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 5ace7efb0d04..696f4c46a868 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -49,6 +49,7 @@ long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned
long arg)
out:
return error;
}
+EXPORT_SYMBOL(vfs_ioctl);
static int ioctl_fibmap(struct file *filp, int __user *p)
{
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 05e3e2f80b89..cc004ff1b05b 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -8,6 +8,7 @@
#include <linux/cred.h>
#include <linux/file.h>
+#include <linux/mount.h>
#include <linux/xattr.h>
#include <linux/uio.h>
#include "overlayfs.h"
@@ -291,6 +292,63 @@ long ovl_fallocate(struct file *file, int mode, loff_t
offset, loff_t len)
return ret;
}
+static long ovl_real_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct fd real;
+ const struct cred *old_cred;
+ long ret;
+
+ ret = ovl_real_file(file, &real);
+ if (ret)
+ return ret;
+
+ old_cred = ovl_override_creds(file_inode(file)->i_sb);
+ ret = vfs_ioctl(real.file, cmd, arg);
+ revert_creds(old_cred);
+
+ fdput(real);
+
+ return ret;
+}
+
+long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ long ret;
+ struct inode *inode = file_inode(file);
+
+ switch (cmd) {
+ case FS_IOC_GETFLAGS:
+ ret = ovl_real_ioctl(file, cmd, arg);
+ break;
+
+ case FS_IOC_SETFLAGS:
+ if (!inode_owner_or_capable(inode))
+ return -EACCES;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ ret = ovl_copy_up(file_dentry(file));
+ if (!ret) {
+ ret = ovl_real_ioctl(file, cmd, arg);
+
+ inode_lock(inode);
+ ovl_copyflags(ovl_inode_real(inode), inode);
+ inode_unlock(inode);
+ }
+
+ mnt_drop_write_file(file);
+ break;
+
+ default:
+ ret = -ENOTTY;
+ }
+
+ return ret;
+}
+
const struct file_operations ovl_file_operations = {
.open = ovl_open,
.release = ovl_release,
@@ -300,4 +358,5 @@ const struct file_operations ovl_file_operations = {
.fsync = ovl_fsync,
.mmap = ovl_mmap,
.fallocate = ovl_fallocate,
+ .unlocked_ioctl = ovl_ioctl,
What about compat_ioctl ? should that implementation also go in the same
patch ?
};
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 0b215faa30ae..1add10f04b56 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1621,6 +1621,8 @@ int vfs_mkobj(struct dentry *, umode_t,
int (*f)(struct dentry *, umode_t, void *),
void *);
+extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+
/*
* VFS file helper functions.
*/
--
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Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
Linux Foundation Collaborative Project.
