diff options
Diffstat (limited to 'module/os/linux/zfs/zpl_file_range.c')
-rw-r--r-- | module/os/linux/zfs/zpl_file_range.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/module/os/linux/zfs/zpl_file_range.c b/module/os/linux/zfs/zpl_file_range.c new file mode 100644 index 000000000000..64728fdb1187 --- /dev/null +++ b/module/os/linux/zfs/zpl_file_range.c @@ -0,0 +1,299 @@ +/* + * 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) || \ + defined(HAVE_VFS_FILE_OPERATIONS_EXTEND) +/* + * 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 || HAVE_VFS_FILE_OPERATIONS_EXTEND */ + +#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) || \ + defined(HAVE_VFS_FILE_OPERATIONS_EXTEND) +/* + * 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 || HAVE_VFS_FILE_OPERATIONS_EXTEND */ + +#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); +} |