From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: Re: [PATCH v2 32/35] Partially revert "locks: fix file locking on overlayfs" Date: Tue, 08 May 2018 11:15:47 -0400 Message-ID: <129bf5c889e3317d6372a2f251cbd56458347224.camel@kernel.org> References: <20180507083807.28792-1-mszeredi@redhat.com> <20180507083807.28792-33-mszeredi@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180507083807.28792-33-mszeredi@redhat.com> Sender: linux-kernel-owner@vger.kernel.org To: Miklos Szeredi , linux-unionfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Al Viro List-Id: linux-unionfs@vger.kernel.org On Mon, 2018-05-07 at 10:38 +0200, Miklos Szeredi wrote: > This partially reverts commit c568d68341be7030f5647def68851e469b21ca11. > > Overlayfs files will now automatically get the correct locks, no need to > hack overlay support in VFS. > > It is a partial revert, because it leaves the locks_inode() calls in place > and defines locks_inode() to file_inode(). We could revert those as well, > but it would be unnecessary code churn and it makes sense to document that > we are getting the inode for locking purposes. > > Signed-off-by: Miklos Szeredi > --- > fs/locks.c | 17 ++++++----------- > fs/overlayfs/super.c | 2 +- > include/linux/fs.h | 13 +------------ > include/uapi/linux/fs.h | 1 - > 4 files changed, 8 insertions(+), 25 deletions(-) > > diff --git a/fs/locks.c b/fs/locks.c > index 9c0e5f3da66c..40bcbaaa3f52 100644 > --- a/fs/locks.c > +++ b/fs/locks.c > @@ -139,11 +139,6 @@ > #define IS_OFDLCK(fl) (fl->fl_flags & FL_OFDLCK) > #define IS_REMOTELCK(fl) (fl->fl_pid <= 0) > > -static inline bool is_remote_lock(struct file *filp) > -{ > - return likely(!(filp->f_path.dentry->d_sb->s_flags & SB_NOREMOTELOCK)); > -} > - > static bool lease_breaking(struct file_lock *fl) > { > return fl->fl_flags & (FL_UNLOCK_PENDING | FL_DOWNGRADE_PENDING); > @@ -1875,7 +1870,7 @@ EXPORT_SYMBOL(generic_setlease); > int > vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv) > { > - if (filp->f_op->setlease && is_remote_lock(filp)) > + if (filp->f_op->setlease) > return filp->f_op->setlease(filp, arg, lease, priv); > else > return generic_setlease(filp, arg, lease, priv); > @@ -2022,7 +2017,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) > if (error) > goto out_free; > > - if (f.file->f_op->flock && is_remote_lock(f.file)) > + if (f.file->f_op->flock) > error = f.file->f_op->flock(f.file, > (can_sleep) ? F_SETLKW : F_SETLK, > lock); > @@ -2048,7 +2043,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) > */ > int vfs_test_lock(struct file *filp, struct file_lock *fl) > { > - if (filp->f_op->lock && is_remote_lock(filp)) > + if (filp->f_op->lock) > return filp->f_op->lock(filp, F_GETLK, fl); > posix_test_lock(filp, fl); > return 0; > @@ -2191,7 +2186,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock) > */ > int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf) > { > - if (filp->f_op->lock && is_remote_lock(filp)) > + if (filp->f_op->lock) > return filp->f_op->lock(filp, cmd, fl); > else > return posix_lock_file(filp, fl, conf); > @@ -2513,7 +2508,7 @@ locks_remove_flock(struct file *filp, struct file_lock_context *flctx) > if (list_empty(&flctx->flc_flock)) > return; > > - if (filp->f_op->flock && is_remote_lock(filp)) > + if (filp->f_op->flock) > filp->f_op->flock(filp, F_SETLKW, &fl); > else > flock_lock_inode(inode, &fl); > @@ -2600,7 +2595,7 @@ EXPORT_SYMBOL(posix_unblock_lock); > */ > int vfs_cancel_lock(struct file *filp, struct file_lock *fl) > { > - if (filp->f_op->lock && is_remote_lock(filp)) > + if (filp->f_op->lock) > return filp->f_op->lock(filp, F_CANCELLK, fl); > return 0; > } > diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c > index 7779fc610767..f2a83fabe2eb 100644 > --- a/fs/overlayfs/super.c > +++ b/fs/overlayfs/super.c > @@ -1479,7 +1479,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) > sb->s_op = &ovl_super_operations; > sb->s_xattr = ovl_xattr_handlers; > sb->s_fs_info = ofs; > - sb->s_flags |= SB_POSIXACL | SB_NOREMOTELOCK; > + sb->s_flags |= SB_POSIXACL; > > err = -ENOMEM; > root_dentry = d_make_root(ovl_new_inode(sb, S_IFDIR, 0)); > diff --git a/include/linux/fs.h b/include/linux/fs.h > index ba3078693d4a..417e692a606a 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1050,17 +1050,7 @@ struct file_lock_context { > > extern void send_sigio(struct fown_struct *fown, int fd, int band); > > -/* > - * Return the inode to use for locking > - * > - * For overlayfs this should be the overlay inode, not the real inode returned > - * by file_inode(). For any other fs file_inode(filp) and locks_inode(filp) are > - * equal. > - */ > -static inline struct inode *locks_inode(const struct file *f) > -{ > - return f->f_path.dentry->d_inode; > -} > +#define locks_inode(f) file_inode(f) > > #ifdef CONFIG_FILE_LOCKING > extern int fcntl_getlk(struct file *, unsigned int, struct flock *); > @@ -1300,7 +1290,6 @@ extern int send_sigurg(struct fown_struct *fown); > > /* These sb flags are internal to the kernel */ > #define SB_SUBMOUNT (1<<26) > -#define SB_NOREMOTELOCK (1<<27) > #define SB_NOSEC (1<<28) > #define SB_BORN (1<<29) > #define SB_ACTIVE (1<<30) > diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h > index d2a8313fabd7..2840ddcece73 100644 > --- a/include/uapi/linux/fs.h > +++ b/include/uapi/linux/fs.h > @@ -134,7 +134,6 @@ struct inodes_stat_t { > > /* These sb flags are internal to the kernel */ > #define MS_SUBMOUNT (1<<26) > -#define MS_NOREMOTELOCK (1<<27) > #define MS_NOSEC (1<<28) > #define MS_BORN (1<<29) > #define MS_ACTIVE (1<<30) Acked-by: Jeff Layton