mirror_zfs/module/os/linux/zfs/zpl_file_range.c
Rob Norris 230bc538cb config: remove HAVE_VFS_FILE_OPERATIONS_EXTEND
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #16479
2024-09-18 11:23:50 -07:00

298 lines
7.9 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2023, Klara Inc.
*/
#ifdef CONFIG_COMPAT
#include <linux/compat.h>
#endif
#include <linux/fs.h>
#ifdef HAVE_VFS_SPLICE_COPY_FILE_RANGE
#include <linux/splice.h>
#endif
#include <sys/file.h>
#include <sys/zfs_znode.h>
#include <sys/zfs_vnops.h>
#include <sys/zfeature.h>
/*
* Clone part of a file via block cloning.
*
* Note that we are not required to update file offsets; the kernel will take
* care of that depending on how it was called.
*/
static ssize_t
zpl_clone_file_range_impl(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, size_t len)
{
struct inode *src_i = file_inode(src_file);
struct inode *dst_i = file_inode(dst_file);
uint64_t src_off_o = (uint64_t)src_off;
uint64_t dst_off_o = (uint64_t)dst_off;
uint64_t len_o = (uint64_t)len;
cred_t *cr = CRED();
fstrans_cookie_t cookie;
int err;
if (!zfs_bclone_enabled)
return (-EOPNOTSUPP);
if (!spa_feature_is_enabled(
dmu_objset_spa(ITOZSB(dst_i)->z_os), SPA_FEATURE_BLOCK_CLONING))
return (-EOPNOTSUPP);
if (src_i != dst_i)
spl_inode_lock_shared(src_i);
spl_inode_lock(dst_i);
crhold(cr);
cookie = spl_fstrans_mark();
err = -zfs_clone_range(ITOZ(src_i), &src_off_o, ITOZ(dst_i),
&dst_off_o, &len_o, cr);
spl_fstrans_unmark(cookie);
crfree(cr);
spl_inode_unlock(dst_i);
if (src_i != dst_i)
spl_inode_unlock_shared(src_i);
if (err < 0)
return (err);
return ((ssize_t)len_o);
}
#if defined(HAVE_VFS_COPY_FILE_RANGE)
/*
* Entry point for copy_file_range(). Copy len bytes from src_off in src_file
* to dst_off in dst_file. We are permitted to do this however we like, so we
* try to just clone the blocks, and if we can't support it, fall back to the
* kernel's generic byte copy function.
*/
ssize_t
zpl_copy_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, size_t len, unsigned int flags)
{
ssize_t ret;
/* Flags is reserved for future extensions and must be zero. */
if (flags != 0)
return (-EINVAL);
/* Try to do it via zfs_clone_range() and allow shortening. */
ret = zpl_clone_file_range_impl(src_file, src_off,
dst_file, dst_off, len);
#if defined(HAVE_VFS_GENERIC_COPY_FILE_RANGE)
/*
* Since Linux 5.3 the filesystem driver is responsible for executing
* an appropriate fallback, and a generic fallback function is provided.
*/
if (ret == -EOPNOTSUPP || ret == -EINVAL || ret == -EXDEV ||
ret == -EAGAIN)
ret = generic_copy_file_range(src_file, src_off, dst_file,
dst_off, len, flags);
#elif defined(HAVE_VFS_SPLICE_COPY_FILE_RANGE)
/*
* Since 6.8 the fallback function is called splice_copy_file_range
* and has a slightly different signature.
*/
if (ret == -EOPNOTSUPP || ret == -EINVAL || ret == -EXDEV ||
ret == -EAGAIN)
ret = splice_copy_file_range(src_file, src_off, dst_file,
dst_off, len);
#else
/*
* Before Linux 5.3 the filesystem has to return -EOPNOTSUPP to signal
* to the kernel that it should fallback to a content copy.
*/
if (ret == -EINVAL || ret == -EXDEV || ret == -EAGAIN)
ret = -EOPNOTSUPP;
#endif /* HAVE_VFS_GENERIC_COPY_FILE_RANGE || HAVE_VFS_SPLICE_COPY_FILE_RANGE */
return (ret);
}
#endif /* HAVE_VFS_COPY_FILE_RANGE */
#ifdef HAVE_VFS_REMAP_FILE_RANGE
/*
* Entry point for FICLONE/FICLONERANGE/FIDEDUPERANGE.
*
* FICLONE and FICLONERANGE are basically the same as copy_file_range(), except
* that they must clone - they cannot fall back to copying. FICLONE is exactly
* FICLONERANGE, for the entire file. We don't need to try to tell them apart;
* the kernel will sort that out for us.
*
* FIDEDUPERANGE is for turning a non-clone into a clone, that is, compare the
* range in both files and if they're the same, arrange for them to be backed
* by the same storage.
*
* REMAP_FILE_CAN_SHORTEN lets us know we can clone less than the given range
* if we want. It's designed for filesystems that may need to shorten the
* length for alignment, EOF, or any other requirement. ZFS may shorten the
* request when there is outstanding dirty data which hasn't been written.
*/
loff_t
zpl_remap_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, loff_t len, unsigned int flags)
{
if (flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_CAN_SHORTEN))
return (-EINVAL);
/* No support for dedup yet */
if (flags & REMAP_FILE_DEDUP)
return (-EOPNOTSUPP);
/* Zero length means to clone everything to the end of the file */
if (len == 0)
len = i_size_read(file_inode(src_file)) - src_off;
ssize_t ret = zpl_clone_file_range_impl(src_file, src_off,
dst_file, dst_off, len);
if (!(flags & REMAP_FILE_CAN_SHORTEN) && ret >= 0 && ret != len)
ret = -EINVAL;
return (ret);
}
#endif /* HAVE_VFS_REMAP_FILE_RANGE */
#if defined(HAVE_VFS_CLONE_FILE_RANGE)
/*
* Entry point for FICLONE and FICLONERANGE, before Linux 4.20.
*/
int
zpl_clone_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, uint64_t len)
{
/* Zero length means to clone everything to the end of the file */
if (len == 0)
len = i_size_read(file_inode(src_file)) - src_off;
/* The entire length must be cloned or this is an error. */
ssize_t ret = zpl_clone_file_range_impl(src_file, src_off,
dst_file, dst_off, len);
if (ret >= 0 && ret != len)
ret = -EINVAL;
return (ret);
}
#endif /* HAVE_VFS_CLONE_FILE_RANGE */
#ifdef HAVE_VFS_DEDUPE_FILE_RANGE
/*
* Entry point for FIDEDUPERANGE, before Linux 4.20.
*/
int
zpl_dedupe_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, uint64_t len)
{
/* No support for dedup yet */
return (-EOPNOTSUPP);
}
#endif /* HAVE_VFS_DEDUPE_FILE_RANGE */
/* Entry point for FICLONE, before Linux 4.5. */
long
zpl_ioctl_ficlone(struct file *dst_file, void *arg)
{
unsigned long sfd = (unsigned long)arg;
struct file *src_file = fget(sfd);
if (src_file == NULL)
return (-EBADF);
if (dst_file->f_op != src_file->f_op) {
fput(src_file);
return (-EXDEV);
}
size_t len = i_size_read(file_inode(src_file));
ssize_t ret = zpl_clone_file_range_impl(src_file, 0, dst_file, 0, len);
fput(src_file);
if (ret < 0) {
if (ret == -EOPNOTSUPP)
return (-ENOTTY);
return (ret);
}
if (ret != len)
return (-EINVAL);
return (0);
}
/* Entry point for FICLONERANGE, before Linux 4.5. */
long
zpl_ioctl_ficlonerange(struct file *dst_file, void __user *arg)
{
zfs_ioc_compat_file_clone_range_t fcr;
if (copy_from_user(&fcr, arg, sizeof (fcr)))
return (-EFAULT);
struct file *src_file = fget(fcr.fcr_src_fd);
if (src_file == NULL)
return (-EBADF);
if (dst_file->f_op != src_file->f_op) {
fput(src_file);
return (-EXDEV);
}
size_t len = fcr.fcr_src_length;
if (len == 0)
len = i_size_read(file_inode(src_file)) - fcr.fcr_src_offset;
ssize_t ret = zpl_clone_file_range_impl(src_file, fcr.fcr_src_offset,
dst_file, fcr.fcr_dest_offset, len);
fput(src_file);
if (ret < 0) {
if (ret == -EOPNOTSUPP)
return (-ENOTTY);
return (ret);
}
if (ret != len)
return (-EINVAL);
return (0);
}
/* Entry point for FIDEDUPERANGE, before Linux 4.5. */
long
zpl_ioctl_fideduperange(struct file *filp, void *arg)
{
(void) arg;
/* No support for dedup yet */
return (-ENOTTY);
}