From patchwork Tue Jul 30 05:15:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 13746636 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E01C19066C; Tue, 30 Jul 2024 05:14:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722316494; cv=none; b=V1rsXnUxLLaJPfPxBoIRwEXahFWWz4Kz8J14zYjOuoflfuzADcrSAEPsl8G5XS9e7PkMQp5rS0a77gLDgEMfoupkG45vbSyLPVM//RLXGGJysd58lyV7T2pHz+tY3hz5JHzaQhaIqPuKX7zYe4D2U1whSg0E0PodbNK6ZN9/gmE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722316494; c=relaxed/simple; bh=GMiamKtcXQUOWKUGB80s5vm8czVFoIjuCig72yQL8LM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=WjggxcsZnRA7L6vAoLDLcegNCbCSk0ggmfG8KpdobSEPqra9plnH58TOMoqLaCzaPoUqVN65wUFiVYbIFP8bjk9KJQX3nAEuBfbCXQvMfmrVZhMgaTGjCql4WRbu+iqbewLuRn3zGuwqJqy9NVE9SdXAv75V6h32hYSreBa8DQc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=axZp9i4w; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="axZp9i4w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 733B6C32782; Tue, 30 Jul 2024 05:14:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722316494; bh=GMiamKtcXQUOWKUGB80s5vm8czVFoIjuCig72yQL8LM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=axZp9i4wvzi2Yd+etF2WcVPLBnouEb7GqJkhMW5Fi4r8vgTv9dYTL39WWhdQxCOhG kitMmpDG2NJeuri6vNviV1nZr0TI1a3Dt6rEl5bN2arazA5bA8tTWqjMEYUdq3w2mp c+HDFBaDty8nyE80Gx4gvdZJ1jLmSkyJWL0+TsHAfN/HgLteIIet/uZECVlq9HltkX c0DqXi227QCIds55KZbvyPRid5D/hXam8e3oYRl84fsNiWa/q3QE6dGbSADqGl8doi REzyBc9/EWFMFECcAzxIKTA7ZEGLCCLwDh/GDkDoXhq6XE5ScqZN2JY6JeBY/fVhwQ aLyWsaaJd/cMg== From: viro@kernel.org To: linux-fsdevel@vger.kernel.org Cc: amir73il@gmail.com, bpf@vger.kernel.org, brauner@kernel.org, cgroups@vger.kernel.org, kvm@vger.kernel.org, netdev@vger.kernel.org, torvalds@linux-foundation.org Subject: [PATCH 08/39] experimental: convert fs/overlayfs/file.c to CLASS(...) Date: Tue, 30 Jul 2024 01:15:54 -0400 Message-Id: <20240730051625.14349-8-viro@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240730051625.14349-1-viro@kernel.org> References: <20240730050927.GC5334@ZenIV> <20240730051625.14349-1-viro@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Al Viro There are four places where we end up adding an extra scope covering just the range from constructor to destructor; not sure if that's the best way to handle that. The functions in question are ovl_write_iter(), ovl_splice_write(), ovl_fadvise() and ovl_copyfile(). This is very likely *NOT* the final form of that thing - it needs to be discussed. Signed-off-by: Al Viro Reviewed-by: Christian Brauner --- fs/overlayfs/file.c | 72 ++++++++++++++++++--------------------------- 1 file changed, 29 insertions(+), 43 deletions(-) diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 4b9e145bc7b8..a2911c632137 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -132,6 +132,8 @@ static struct fderr ovl_real_fdget(const struct file *file) return ovl_real_fdget_meta(file, false); } +DEFINE_CLASS(fd_real, struct fderr, fdput(_T), ovl_real_fdget(file), struct file *file) + static int ovl_open(struct inode *inode, struct file *file) { struct dentry *dentry = file_dentry(file); @@ -174,7 +176,6 @@ static int ovl_release(struct inode *inode, struct file *file) static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) { struct inode *inode = file_inode(file); - struct fderr real; const struct cred *old_cred; loff_t ret; @@ -190,7 +191,7 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) return vfs_setpos(file, 0, 0); } - real = ovl_real_fdget(file); + CLASS(fd_real, real)(file); if (fd_empty(real)) return fd_error(real); @@ -211,8 +212,6 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence) file->f_pos = fd_file(real)->f_pos; ovl_inode_unlock(inode); - fdput(real); - return ret; } @@ -253,8 +252,6 @@ static void ovl_file_accessed(struct file *file) static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; - struct fderr real; - ssize_t ret; struct backing_file_ctx ctx = { .cred = ovl_creds(file_inode(file)->i_sb), .user_file = file, @@ -264,22 +261,18 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter) if (!iov_iter_count(iter)) return 0; - real = ovl_real_fdget(file); + CLASS(fd_real, real)(file); if (fd_empty(real)) return fd_error(real); - ret = backing_file_read_iter(fd_file(real), iter, iocb, iocb->ki_flags, - &ctx); - fdput(real); - - return ret; + return backing_file_read_iter(fd_file(real), iter, iocb, iocb->ki_flags, + &ctx); } static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; struct inode *inode = file_inode(file); - struct fderr real; ssize_t ret; int ifl = iocb->ki_flags; struct backing_file_ctx ctx = { @@ -295,7 +288,9 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) /* Update mode */ ovl_copyattr(inode); - real = ovl_real_fdget(file); + { + + CLASS(fd_real, real)(file); if (fd_empty(real)) { ret = fd_error(real); goto out_unlock; @@ -310,7 +305,8 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) */ ifl &= ~IOCB_DIO_CALLER_COMP; ret = backing_file_write_iter(fd_file(real), iter, iocb, ifl, &ctx); - fdput(real); + + } out_unlock: inode_unlock(inode); @@ -322,22 +318,18 @@ static ssize_t ovl_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { - struct fderr real; - ssize_t ret; + CLASS(fd_real, real)(in); struct backing_file_ctx ctx = { .cred = ovl_creds(file_inode(in)->i_sb), .user_file = in, .accessed = ovl_file_accessed, }; - real = ovl_real_fdget(in); if (fd_empty(real)) return fd_error(real); - ret = backing_file_splice_read(fd_file(real), ppos, pipe, len, flags, &ctx); - fdput(real); - - return ret; + return backing_file_splice_read(fd_file(real), ppos, pipe, len, flags, + &ctx); } /* @@ -351,7 +343,6 @@ static ssize_t ovl_splice_read(struct file *in, loff_t *ppos, static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out, loff_t *ppos, size_t len, unsigned int flags) { - struct fderr real; struct inode *inode = file_inode(out); ssize_t ret; struct backing_file_ctx ctx = { @@ -364,15 +355,17 @@ static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out, /* Update mode */ ovl_copyattr(inode); - real = ovl_real_fdget(out); + { + + CLASS(fd_real, real)(out); if (fd_empty(real)) { ret = fd_error(real); goto out_unlock; } ret = backing_file_splice_write(pipe, fd_file(real), ppos, len, flags, &ctx); - fdput(real); + } out_unlock: inode_unlock(inode); @@ -420,7 +413,6 @@ static int ovl_mmap(struct file *file, struct vm_area_struct *vma) static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len) { struct inode *inode = file_inode(file); - struct fderr real; const struct cred *old_cred; int ret; @@ -430,7 +422,9 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len ret = file_remove_privs(file); if (ret) goto out_unlock; - real = ovl_real_fdget(file); + { + + CLASS(fd_real, real)(file); if (fd_empty(real)) { ret = fd_error(real); goto out_unlock; @@ -443,8 +437,7 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len /* Update size */ ovl_file_modified(file); - fdput(real); - + } out_unlock: inode_unlock(inode); @@ -453,11 +446,10 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice) { - struct fderr real; + CLASS(fd_real, real)(file); const struct cred *old_cred; int ret; - real = ovl_real_fdget(file); if (fd_empty(real)) return fd_error(real); @@ -465,8 +457,6 @@ static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice) ret = vfs_fadvise(fd_file(real), offset, len, advice); revert_creds(old_cred); - fdput(real); - return ret; } @@ -481,7 +471,6 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, loff_t len, unsigned int flags, enum ovl_copyop op) { struct inode *inode_out = file_inode(file_out); - struct fderr real_in, real_out; const struct cred *old_cred; loff_t ret; @@ -494,15 +483,16 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, goto out_unlock; } - real_out = ovl_real_fdget(file_out); + { + + CLASS(fd_real, real_out)(file_out); if (fd_empty(real_out)) { ret = fd_error(real_out); goto out_unlock; } - real_in = ovl_real_fdget(file_in); + CLASS(fd_real, real_in)(file_in); if (fd_empty(real_in)) { - fdput(real_out); ret = fd_error(real_in); goto out_unlock; } @@ -530,8 +520,7 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, /* Update size */ ovl_file_modified(file_out); - fdput(real_in); - fdput(real_out); + } out_unlock: inode_unlock(inode_out); @@ -576,11 +565,10 @@ static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in, static int ovl_flush(struct file *file, fl_owner_t id) { - struct fderr real; + CLASS(fd_real, real)(file); const struct cred *old_cred; int err = 0; - real = ovl_real_fdget(file); if (fd_empty(real)) return fd_error(real); @@ -589,8 +577,6 @@ static int ovl_flush(struct file *file, fl_owner_t id) err = fd_file(real)->f_op->flush(fd_file(real), id); revert_creds(old_cred); } - fdput(real); - return err; }