720 lines
16 KiB
C
720 lines
16 KiB
C
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2017 Red Hat, Inc.
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*/
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#include <linux/cred.h>
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#include <linux/file.h>
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#include <linux/mount.h>
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#include <linux/xattr.h>
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#include <linux/uio.h>
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#include <linux/uaccess.h>
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#include <linux/splice.h>
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#include <linux/security.h>
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#include <linux/mm.h>
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#include <linux/fs.h>
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#include "overlayfs.h"
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struct ovl_aio_req {
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struct kiocb iocb;
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refcount_t ref;
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struct kiocb *orig_iocb;
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struct fd fd;
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};
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static struct kmem_cache *ovl_aio_request_cachep;
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static char ovl_whatisit(struct inode *inode, struct inode *realinode)
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{
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if (realinode != ovl_inode_upper(inode))
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return 'l';
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if (ovl_has_upperdata(inode))
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return 'u';
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else
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return 'm';
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}
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/* No atime modification nor notify on underlying */
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#define OVL_OPEN_FLAGS (O_NOATIME | FMODE_NONOTIFY)
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static struct file *ovl_open_realfile(const struct file *file,
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const struct path *realpath)
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{
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struct inode *realinode = d_inode(realpath->dentry);
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struct inode *inode = file_inode(file);
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struct mnt_idmap *real_idmap;
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struct file *realfile;
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const struct cred *old_cred;
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int flags = file->f_flags | OVL_OPEN_FLAGS;
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int acc_mode = ACC_MODE(flags);
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int err;
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if (flags & O_APPEND)
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acc_mode |= MAY_APPEND;
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old_cred = ovl_override_creds(inode->i_sb);
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real_idmap = mnt_idmap(realpath->mnt);
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err = inode_permission(real_idmap, realinode, MAY_OPEN | acc_mode);
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if (err) {
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realfile = ERR_PTR(err);
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} else {
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if (!inode_owner_or_capable(real_idmap, realinode))
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flags &= ~O_NOATIME;
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realfile = open_with_fake_path(&file->f_path, flags, realinode,
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current_cred());
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}
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revert_creds(old_cred);
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pr_debug("open(%p[%pD2/%c], 0%o) -> (%p, 0%o)\n",
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file, file, ovl_whatisit(inode, realinode), file->f_flags,
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realfile, IS_ERR(realfile) ? 0 : realfile->f_flags);
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return realfile;
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}
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#define OVL_SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT)
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static int ovl_change_flags(struct file *file, unsigned int flags)
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{
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struct inode *inode = file_inode(file);
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int err;
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flags &= OVL_SETFL_MASK;
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if (((flags ^ file->f_flags) & O_APPEND) && IS_APPEND(inode))
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return -EPERM;
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if ((flags & O_DIRECT) && !(file->f_mode & FMODE_CAN_ODIRECT))
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return -EINVAL;
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if (file->f_op->check_flags) {
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err = file->f_op->check_flags(flags);
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if (err)
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return err;
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}
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spin_lock(&file->f_lock);
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file->f_flags = (file->f_flags & ~OVL_SETFL_MASK) | flags;
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file->f_iocb_flags = iocb_flags(file);
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spin_unlock(&file->f_lock);
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return 0;
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}
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static int ovl_real_fdget_meta(const struct file *file, struct fd *real,
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bool allow_meta)
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{
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struct dentry *dentry = file_dentry(file);
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struct path realpath;
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real->flags = 0;
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real->file = file->private_data;
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if (allow_meta)
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ovl_path_real(dentry, &realpath);
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else
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ovl_path_realdata(dentry, &realpath);
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/* Has it been copied up since we'd opened it? */
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if (unlikely(file_inode(real->file) != d_inode(realpath.dentry))) {
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real->flags = FDPUT_FPUT;
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real->file = ovl_open_realfile(file, &realpath);
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return PTR_ERR_OR_ZERO(real->file);
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}
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/* Did the flags change since open? */
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if (unlikely((file->f_flags ^ real->file->f_flags) & ~OVL_OPEN_FLAGS))
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return ovl_change_flags(real->file, file->f_flags);
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return 0;
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}
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static int ovl_real_fdget(const struct file *file, struct fd *real)
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{
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if (d_is_dir(file_dentry(file))) {
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real->flags = 0;
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real->file = ovl_dir_real_file(file, false);
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return PTR_ERR_OR_ZERO(real->file);
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}
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return ovl_real_fdget_meta(file, real, false);
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}
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static int ovl_open(struct inode *inode, struct file *file)
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{
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struct dentry *dentry = file_dentry(file);
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struct file *realfile;
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struct path realpath;
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int err;
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err = ovl_maybe_copy_up(dentry, file->f_flags);
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if (err)
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return err;
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/* No longer need these flags, so don't pass them on to underlying fs */
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file->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
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ovl_path_realdata(dentry, &realpath);
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realfile = ovl_open_realfile(file, &realpath);
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if (IS_ERR(realfile))
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return PTR_ERR(realfile);
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file->private_data = realfile;
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return 0;
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}
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static int ovl_release(struct inode *inode, struct file *file)
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{
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fput(file->private_data);
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return 0;
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}
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static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
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{
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struct inode *inode = file_inode(file);
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struct fd real;
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const struct cred *old_cred;
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loff_t ret;
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/*
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* The two special cases below do not need to involve real fs,
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* so we can optimizing concurrent callers.
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*/
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if (offset == 0) {
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if (whence == SEEK_CUR)
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return file->f_pos;
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if (whence == SEEK_SET)
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return vfs_setpos(file, 0, 0);
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}
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ret = ovl_real_fdget(file, &real);
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if (ret)
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return ret;
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/*
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* Overlay file f_pos is the master copy that is preserved
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* through copy up and modified on read/write, but only real
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* fs knows how to SEEK_HOLE/SEEK_DATA and real fs may impose
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* limitations that are more strict than ->s_maxbytes for specific
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* files, so we use the real file to perform seeks.
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*/
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ovl_inode_lock(inode);
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real.file->f_pos = file->f_pos;
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old_cred = ovl_override_creds(inode->i_sb);
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ret = vfs_llseek(real.file, offset, whence);
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revert_creds(old_cred);
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file->f_pos = real.file->f_pos;
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ovl_inode_unlock(inode);
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fdput(real);
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return ret;
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}
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static void ovl_file_accessed(struct file *file)
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{
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struct inode *inode, *upperinode;
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if (file->f_flags & O_NOATIME)
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return;
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inode = file_inode(file);
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upperinode = ovl_inode_upper(inode);
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if (!upperinode)
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return;
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if ((!timespec64_equal(&inode->i_mtime, &upperinode->i_mtime) ||
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!timespec64_equal(&inode->i_ctime, &upperinode->i_ctime))) {
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inode->i_mtime = upperinode->i_mtime;
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inode->i_ctime = upperinode->i_ctime;
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}
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touch_atime(&file->f_path);
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}
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static rwf_t ovl_iocb_to_rwf(int ifl)
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{
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rwf_t flags = 0;
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if (ifl & IOCB_NOWAIT)
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flags |= RWF_NOWAIT;
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if (ifl & IOCB_HIPRI)
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flags |= RWF_HIPRI;
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if (ifl & IOCB_DSYNC)
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flags |= RWF_DSYNC;
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if (ifl & IOCB_SYNC)
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flags |= RWF_SYNC;
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return flags;
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}
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static inline void ovl_aio_put(struct ovl_aio_req *aio_req)
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{
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if (refcount_dec_and_test(&aio_req->ref)) {
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fdput(aio_req->fd);
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kmem_cache_free(ovl_aio_request_cachep, aio_req);
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}
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}
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static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
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{
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struct kiocb *iocb = &aio_req->iocb;
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struct kiocb *orig_iocb = aio_req->orig_iocb;
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if (iocb->ki_flags & IOCB_WRITE) {
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struct inode *inode = file_inode(orig_iocb->ki_filp);
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/* Actually acquired in ovl_write_iter() */
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__sb_writers_acquired(file_inode(iocb->ki_filp)->i_sb,
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SB_FREEZE_WRITE);
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file_end_write(iocb->ki_filp);
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ovl_copyattr(inode);
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}
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orig_iocb->ki_pos = iocb->ki_pos;
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ovl_aio_put(aio_req);
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}
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static void ovl_aio_rw_complete(struct kiocb *iocb, long res)
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{
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struct ovl_aio_req *aio_req = container_of(iocb,
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struct ovl_aio_req, iocb);
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struct kiocb *orig_iocb = aio_req->orig_iocb;
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ovl_aio_cleanup_handler(aio_req);
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orig_iocb->ki_complete(orig_iocb, res);
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}
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static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
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{
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struct file *file = iocb->ki_filp;
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struct fd real;
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const struct cred *old_cred;
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ssize_t ret;
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if (!iov_iter_count(iter))
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return 0;
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ret = ovl_real_fdget(file, &real);
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if (ret)
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return ret;
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ret = -EINVAL;
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if (iocb->ki_flags & IOCB_DIRECT &&
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!(real.file->f_mode & FMODE_CAN_ODIRECT))
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goto out_fdput;
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old_cred = ovl_override_creds(file_inode(file)->i_sb);
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if (is_sync_kiocb(iocb)) {
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ret = vfs_iter_read(real.file, iter, &iocb->ki_pos,
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ovl_iocb_to_rwf(iocb->ki_flags));
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} else {
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struct ovl_aio_req *aio_req;
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ret = -ENOMEM;
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aio_req = kmem_cache_zalloc(ovl_aio_request_cachep, GFP_KERNEL);
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if (!aio_req)
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goto out;
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aio_req->fd = real;
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real.flags = 0;
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aio_req->orig_iocb = iocb;
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kiocb_clone(&aio_req->iocb, iocb, real.file);
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aio_req->iocb.ki_complete = ovl_aio_rw_complete;
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refcount_set(&aio_req->ref, 2);
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ret = vfs_iocb_iter_read(real.file, &aio_req->iocb, iter);
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ovl_aio_put(aio_req);
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if (ret != -EIOCBQUEUED)
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ovl_aio_cleanup_handler(aio_req);
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}
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out:
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revert_creds(old_cred);
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ovl_file_accessed(file);
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out_fdput:
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fdput(real);
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return ret;
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}
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static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
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{
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struct file *file = iocb->ki_filp;
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struct inode *inode = file_inode(file);
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struct fd real;
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const struct cred *old_cred;
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ssize_t ret;
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int ifl = iocb->ki_flags;
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if (!iov_iter_count(iter))
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return 0;
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inode_lock(inode);
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/* Update mode */
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ovl_copyattr(inode);
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ret = file_remove_privs(file);
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if (ret)
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goto out_unlock;
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ret = ovl_real_fdget(file, &real);
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if (ret)
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goto out_unlock;
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ret = -EINVAL;
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if (iocb->ki_flags & IOCB_DIRECT &&
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|
|
!(real.file->f_mode & FMODE_CAN_ODIRECT))
|
||
|
|
goto out_fdput;
|
||
|
|
|
||
|
|
if (!ovl_should_sync(OVL_FS(inode->i_sb)))
|
||
|
|
ifl &= ~(IOCB_DSYNC | IOCB_SYNC);
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
if (is_sync_kiocb(iocb)) {
|
||
|
|
file_start_write(real.file);
|
||
|
|
ret = vfs_iter_write(real.file, iter, &iocb->ki_pos,
|
||
|
|
ovl_iocb_to_rwf(ifl));
|
||
|
|
file_end_write(real.file);
|
||
|
|
/* Update size */
|
||
|
|
ovl_copyattr(inode);
|
||
|
|
} else {
|
||
|
|
struct ovl_aio_req *aio_req;
|
||
|
|
|
||
|
|
ret = -ENOMEM;
|
||
|
|
aio_req = kmem_cache_zalloc(ovl_aio_request_cachep, GFP_KERNEL);
|
||
|
|
if (!aio_req)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
file_start_write(real.file);
|
||
|
|
/* Pacify lockdep, same trick as done in aio_write() */
|
||
|
|
__sb_writers_release(file_inode(real.file)->i_sb,
|
||
|
|
SB_FREEZE_WRITE);
|
||
|
|
aio_req->fd = real;
|
||
|
|
real.flags = 0;
|
||
|
|
aio_req->orig_iocb = iocb;
|
||
|
|
kiocb_clone(&aio_req->iocb, iocb, real.file);
|
||
|
|
aio_req->iocb.ki_flags = ifl;
|
||
|
|
aio_req->iocb.ki_complete = ovl_aio_rw_complete;
|
||
|
|
refcount_set(&aio_req->ref, 2);
|
||
|
|
ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter);
|
||
|
|
ovl_aio_put(aio_req);
|
||
|
|
if (ret != -EIOCBQUEUED)
|
||
|
|
ovl_aio_cleanup_handler(aio_req);
|
||
|
|
}
|
||
|
|
out:
|
||
|
|
revert_creds(old_cred);
|
||
|
|
out_fdput:
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
inode_unlock(inode);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Calling iter_file_splice_write() directly from overlay's f_op may deadlock
|
||
|
|
* due to lock order inversion between pipe->mutex in iter_file_splice_write()
|
||
|
|
* and file_start_write(real.file) in ovl_write_iter().
|
||
|
|
*
|
||
|
|
* So do everything ovl_write_iter() does and call iter_file_splice_write() on
|
||
|
|
* the real file.
|
||
|
|
*/
|
||
|
|
static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,
|
||
|
|
loff_t *ppos, size_t len, unsigned int flags)
|
||
|
|
{
|
||
|
|
struct fd real;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
struct inode *inode = file_inode(out);
|
||
|
|
ssize_t ret;
|
||
|
|
|
||
|
|
inode_lock(inode);
|
||
|
|
/* Update mode */
|
||
|
|
ovl_copyattr(inode);
|
||
|
|
ret = file_remove_privs(out);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
|
||
|
|
ret = ovl_real_fdget(out, &real);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(inode->i_sb);
|
||
|
|
file_start_write(real.file);
|
||
|
|
|
||
|
|
ret = iter_file_splice_write(pipe, real.file, ppos, len, flags);
|
||
|
|
|
||
|
|
file_end_write(real.file);
|
||
|
|
/* Update size */
|
||
|
|
ovl_copyattr(inode);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
inode_unlock(inode);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ovl_fsync(struct file *file, loff_t start, loff_t end, int datasync)
|
||
|
|
{
|
||
|
|
struct fd real;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = ovl_sync_status(OVL_FS(file_inode(file)->i_sb));
|
||
|
|
if (ret <= 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
ret = ovl_real_fdget_meta(file, &real, !datasync);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Don't sync lower file for fear of receiving EROFS error */
|
||
|
|
if (file_inode(real.file) == ovl_inode_upper(file_inode(file))) {
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
ret = vfs_fsync_range(real.file, start, end, datasync);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
}
|
||
|
|
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ovl_mmap(struct file *file, struct vm_area_struct *vma)
|
||
|
|
{
|
||
|
|
struct file *realfile = file->private_data;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
if (!realfile->f_op->mmap)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
if (WARN_ON(file != vma->vm_file))
|
||
|
|
return -EIO;
|
||
|
|
|
||
|
|
vma_set_file(vma, realfile);
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
ret = call_mmap(vma->vm_file, vma);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
ovl_file_accessed(file);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
|
||
|
|
{
|
||
|
|
struct inode *inode = file_inode(file);
|
||
|
|
struct fd real;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
inode_lock(inode);
|
||
|
|
/* Update mode */
|
||
|
|
ovl_copyattr(inode);
|
||
|
|
ret = file_remove_privs(file);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
|
||
|
|
ret = ovl_real_fdget(file, &real);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
ret = vfs_fallocate(real.file, mode, offset, len);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
|
||
|
|
/* Update size */
|
||
|
|
ovl_copyattr(inode);
|
||
|
|
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
inode_unlock(inode);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)
|
||
|
|
{
|
||
|
|
struct fd real;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = ovl_real_fdget(file, &real);
|
||
|
|
if (ret)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
ret = vfs_fadvise(real.file, offset, len, advice);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
enum ovl_copyop {
|
||
|
|
OVL_COPY,
|
||
|
|
OVL_CLONE,
|
||
|
|
OVL_DEDUPE,
|
||
|
|
};
|
||
|
|
|
||
|
|
static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
|
||
|
|
struct file *file_out, loff_t pos_out,
|
||
|
|
loff_t len, unsigned int flags, enum ovl_copyop op)
|
||
|
|
{
|
||
|
|
struct inode *inode_out = file_inode(file_out);
|
||
|
|
struct fd real_in, real_out;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
loff_t ret;
|
||
|
|
|
||
|
|
inode_lock(inode_out);
|
||
|
|
if (op != OVL_DEDUPE) {
|
||
|
|
/* Update mode */
|
||
|
|
ovl_copyattr(inode_out);
|
||
|
|
ret = file_remove_privs(file_out);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
ret = ovl_real_fdget(file_out, &real_out);
|
||
|
|
if (ret)
|
||
|
|
goto out_unlock;
|
||
|
|
|
||
|
|
ret = ovl_real_fdget(file_in, &real_in);
|
||
|
|
if (ret) {
|
||
|
|
fdput(real_out);
|
||
|
|
goto out_unlock;
|
||
|
|
}
|
||
|
|
|
||
|
|
old_cred = ovl_override_creds(file_inode(file_out)->i_sb);
|
||
|
|
switch (op) {
|
||
|
|
case OVL_COPY:
|
||
|
|
ret = vfs_copy_file_range(real_in.file, pos_in,
|
||
|
|
real_out.file, pos_out, len, flags);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case OVL_CLONE:
|
||
|
|
ret = vfs_clone_file_range(real_in.file, pos_in,
|
||
|
|
real_out.file, pos_out, len, flags);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case OVL_DEDUPE:
|
||
|
|
ret = vfs_dedupe_file_range_one(real_in.file, pos_in,
|
||
|
|
real_out.file, pos_out, len,
|
||
|
|
flags);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
revert_creds(old_cred);
|
||
|
|
|
||
|
|
/* Update size */
|
||
|
|
ovl_copyattr(inode_out);
|
||
|
|
|
||
|
|
fdput(real_in);
|
||
|
|
fdput(real_out);
|
||
|
|
|
||
|
|
out_unlock:
|
||
|
|
inode_unlock(inode_out);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in,
|
||
|
|
struct file *file_out, loff_t pos_out,
|
||
|
|
size_t len, unsigned int flags)
|
||
|
|
{
|
||
|
|
return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags,
|
||
|
|
OVL_COPY);
|
||
|
|
}
|
||
|
|
|
||
|
|
static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,
|
||
|
|
struct file *file_out, loff_t pos_out,
|
||
|
|
loff_t len, unsigned int remap_flags)
|
||
|
|
{
|
||
|
|
enum ovl_copyop op;
|
||
|
|
|
||
|
|
if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
|
||
|
|
return -EINVAL;
|
||
|
|
|
||
|
|
if (remap_flags & REMAP_FILE_DEDUP)
|
||
|
|
op = OVL_DEDUPE;
|
||
|
|
else
|
||
|
|
op = OVL_CLONE;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Don't copy up because of a dedupe request, this wouldn't make sense
|
||
|
|
* most of the time (data would be duplicated instead of deduplicated).
|
||
|
|
*/
|
||
|
|
if (op == OVL_DEDUPE &&
|
||
|
|
(!ovl_inode_upper(file_inode(file_in)) ||
|
||
|
|
!ovl_inode_upper(file_inode(file_out))))
|
||
|
|
return -EPERM;
|
||
|
|
|
||
|
|
return ovl_copyfile(file_in, pos_in, file_out, pos_out, len,
|
||
|
|
remap_flags, op);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int ovl_flush(struct file *file, fl_owner_t id)
|
||
|
|
{
|
||
|
|
struct fd real;
|
||
|
|
const struct cred *old_cred;
|
||
|
|
int err;
|
||
|
|
|
||
|
|
err = ovl_real_fdget(file, &real);
|
||
|
|
if (err)
|
||
|
|
return err;
|
||
|
|
|
||
|
|
if (real.file->f_op->flush) {
|
||
|
|
old_cred = ovl_override_creds(file_inode(file)->i_sb);
|
||
|
|
err = real.file->f_op->flush(real.file, id);
|
||
|
|
revert_creds(old_cred);
|
||
|
|
}
|
||
|
|
fdput(real);
|
||
|
|
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
const struct file_operations ovl_file_operations = {
|
||
|
|
.open = ovl_open,
|
||
|
|
.release = ovl_release,
|
||
|
|
.llseek = ovl_llseek,
|
||
|
|
.read_iter = ovl_read_iter,
|
||
|
|
.write_iter = ovl_write_iter,
|
||
|
|
.fsync = ovl_fsync,
|
||
|
|
.mmap = ovl_mmap,
|
||
|
|
.fallocate = ovl_fallocate,
|
||
|
|
.fadvise = ovl_fadvise,
|
||
|
|
.flush = ovl_flush,
|
||
|
|
.splice_read = generic_file_splice_read,
|
||
|
|
.splice_write = ovl_splice_write,
|
||
|
|
|
||
|
|
.copy_file_range = ovl_copy_file_range,
|
||
|
|
.remap_file_range = ovl_remap_file_range,
|
||
|
|
};
|
||
|
|
|
||
|
|
int __init ovl_aio_request_cache_init(void)
|
||
|
|
{
|
||
|
|
ovl_aio_request_cachep = kmem_cache_create("ovl_aio_req",
|
||
|
|
sizeof(struct ovl_aio_req),
|
||
|
|
0, SLAB_HWCACHE_ALIGN, NULL);
|
||
|
|
if (!ovl_aio_request_cachep)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void ovl_aio_request_cache_destroy(void)
|
||
|
|
{
|
||
|
|
kmem_cache_destroy(ovl_aio_request_cachep);
|
||
|
|
}
|