There are several FUSE filesystems that can implement server-side copy or other efficient copy/duplication/clone methods. The copy_file_range() syscall is the standard interface that users have access to while not depending on external libraries that bypass FUSE.
Signed-off-by: Niels de Vos <nde...@redhat.com> --- libfuse: https://github.com/libfuse/libfuse/pull/259 v2: return ssize_t instead of long v3: add nodeid_out to fuse_copy_file_range_in for libfuse expectations v4: use fuse_write_out as response, correct write-back handling --- fs/fuse/file.c | 80 +++++++++++++++++++++++++++++ fs/fuse/fuse_i.h | 3 ++ include/uapi/linux/fuse.h | 104 +++++++++++++++++++++----------------- 3 files changed, 142 insertions(+), 45 deletions(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index a201fb0ac64f..6aea3675fd88 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -3009,6 +3009,85 @@ static long fuse_file_fallocate(struct file *file, int mode, loff_t offset, return err; } +static ssize_t fuse_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) +{ + struct fuse_file *ff_in = file_in->private_data; + struct fuse_file *ff_out = file_out->private_data; + struct inode *inode_out = file_inode(file_out); + struct fuse_inode *fi_out = get_fuse_inode(inode_out); + struct fuse_conn *fc = ff_in->fc; + FUSE_ARGS(args); + struct fuse_copy_file_range_in inarg = { + .fh_in = ff_in->fh, + .off_in = pos_in, + .nodeid_out = ff_out->nodeid, + .fh_out = ff_out->fh, + .off_out = pos_out, + .len = len, + .flags = flags + }; + struct fuse_write_out outarg; + ssize_t err; + /* mark unstable when write-back is not used, and file_out gets + * extended */ + bool is_unstable = (!fc->writeback_cache) && + ((pos_out + len) > inode_out->i_size); + + if (fc->no_copy_file_range) + return -EOPNOTSUPP; + + inode_lock(inode_out); + + if (fc->writeback_cache) { + err = filemap_write_and_wait_range(inode_out->i_mapping, + pos_out, pos_out + len); + if (err) + goto out; + + fuse_sync_writes(inode_out); + } + + if (is_unstable) + set_bit(FUSE_I_SIZE_UNSTABLE, &fi_out->state); + + args.in.h.opcode = FUSE_COPY_FILE_RANGE; + args.in.h.nodeid = ff_in->nodeid; + args.in.numargs = 1; + args.in.args[0].size = sizeof(inarg); + args.in.args[0].value = &inarg; + args.out.numargs = 1; + args.out.args[0].size = sizeof(outarg); + args.out.args[0].value = &outarg; + err = fuse_simple_request(fc, &args); + if (err == -ENOSYS) { + fc->no_copy_file_range = 1; + err = -EOPNOTSUPP; + } + if (err) + goto out; + + if (fc->writeback_cache) { + bool changed = fuse_write_update_size(inode_out, + pos_out + outarg.size); + + if (changed) + file_update_time(file_out); + } + + fuse_invalidate_attr(inode_out); + + err = outarg.size; +out: + if (is_unstable) + clear_bit(FUSE_I_SIZE_UNSTABLE, &fi_out->state); + + inode_unlock(inode_out); + + return err; +} + static const struct file_operations fuse_file_operations = { .llseek = fuse_file_llseek, .read_iter = fuse_file_read_iter, @@ -3025,6 +3104,7 @@ static const struct file_operations fuse_file_operations = { .compat_ioctl = fuse_file_compat_ioctl, .poll = fuse_file_poll, .fallocate = fuse_file_fallocate, + .copy_file_range = fuse_copy_file_range, }; static const struct file_operations fuse_direct_io_file_operations = { diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 5256ad333b05..ea848bb7d9e2 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -637,6 +637,9 @@ struct fuse_conn { /** Allow other than the mounter user to access the filesystem ? */ unsigned allow_other:1; + /** Does the filesystem support copy_file_range? */ + unsigned no_copy_file_range:1; + /** The number of requests waiting for completion */ atomic_t num_waiting; diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 92fa24c24c92..c806a17beaef 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -116,6 +116,9 @@ * * 7.27 * - add FUSE_ABORT_ERROR + * + * 7.28 + * - add FUSE_COPY_FILE_RANGE */ #ifndef _LINUX_FUSE_H @@ -337,53 +340,54 @@ struct fuse_file_lock { #define FUSE_POLL_SCHEDULE_NOTIFY (1 << 0) enum fuse_opcode { - FUSE_LOOKUP = 1, - FUSE_FORGET = 2, /* no reply */ - FUSE_GETATTR = 3, - FUSE_SETATTR = 4, - FUSE_READLINK = 5, - FUSE_SYMLINK = 6, - FUSE_MKNOD = 8, - FUSE_MKDIR = 9, - FUSE_UNLINK = 10, - FUSE_RMDIR = 11, - FUSE_RENAME = 12, - FUSE_LINK = 13, - FUSE_OPEN = 14, - FUSE_READ = 15, - FUSE_WRITE = 16, - FUSE_STATFS = 17, - FUSE_RELEASE = 18, - FUSE_FSYNC = 20, - FUSE_SETXATTR = 21, - FUSE_GETXATTR = 22, - FUSE_LISTXATTR = 23, - FUSE_REMOVEXATTR = 24, - FUSE_FLUSH = 25, - FUSE_INIT = 26, - FUSE_OPENDIR = 27, - FUSE_READDIR = 28, - FUSE_RELEASEDIR = 29, - FUSE_FSYNCDIR = 30, - FUSE_GETLK = 31, - FUSE_SETLK = 32, - FUSE_SETLKW = 33, - FUSE_ACCESS = 34, - FUSE_CREATE = 35, - FUSE_INTERRUPT = 36, - FUSE_BMAP = 37, - FUSE_DESTROY = 38, - FUSE_IOCTL = 39, - FUSE_POLL = 40, - FUSE_NOTIFY_REPLY = 41, - FUSE_BATCH_FORGET = 42, - FUSE_FALLOCATE = 43, - FUSE_READDIRPLUS = 44, - FUSE_RENAME2 = 45, - FUSE_LSEEK = 46, + FUSE_LOOKUP = 1, + FUSE_FORGET = 2, /* no reply */ + FUSE_GETATTR = 3, + FUSE_SETATTR = 4, + FUSE_READLINK = 5, + FUSE_SYMLINK = 6, + FUSE_MKNOD = 8, + FUSE_MKDIR = 9, + FUSE_UNLINK = 10, + FUSE_RMDIR = 11, + FUSE_RENAME = 12, + FUSE_LINK = 13, + FUSE_OPEN = 14, + FUSE_READ = 15, + FUSE_WRITE = 16, + FUSE_STATFS = 17, + FUSE_RELEASE = 18, + FUSE_FSYNC = 20, + FUSE_SETXATTR = 21, + FUSE_GETXATTR = 22, + FUSE_LISTXATTR = 23, + FUSE_REMOVEXATTR = 24, + FUSE_FLUSH = 25, + FUSE_INIT = 26, + FUSE_OPENDIR = 27, + FUSE_READDIR = 28, + FUSE_RELEASEDIR = 29, + FUSE_FSYNCDIR = 30, + FUSE_GETLK = 31, + FUSE_SETLK = 32, + FUSE_SETLKW = 33, + FUSE_ACCESS = 34, + FUSE_CREATE = 35, + FUSE_INTERRUPT = 36, + FUSE_BMAP = 37, + FUSE_DESTROY = 38, + FUSE_IOCTL = 39, + FUSE_POLL = 40, + FUSE_NOTIFY_REPLY = 41, + FUSE_BATCH_FORGET = 42, + FUSE_FALLOCATE = 43, + FUSE_READDIRPLUS = 44, + FUSE_RENAME2 = 45, + FUSE_LSEEK = 46, + FUSE_COPY_FILE_RANGE = 47, /* CUSE specific operations */ - CUSE_INIT = 4096, + CUSE_INIT = 4096, }; enum fuse_notify_code { @@ -792,4 +796,14 @@ struct fuse_lseek_out { uint64_t offset; }; +struct fuse_copy_file_range_in { + uint64_t fh_in; + uint64_t off_in; + uint64_t nodeid_out; + uint64_t fh_out; + uint64_t off_out; + uint64_t len; + uint64_t flags; +}; + #endif /* _LINUX_FUSE_H */ -- 2.17.1
