Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse updates from Miklos Szeredi:
"This fixes a regression (spotted by the Sandstorm.io folks) in the pid
namespace handling introduced in 4.12.

There's also a fix for honoring sync/dsync flags for pwritev2()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: getattr cleanup
fuse: honor iocb sync flags on write
fuse: allow server to run in different pid_ns

fs/fuse/cuse.c

···
 
 static ssize_t cuse_read_iter(struct kiocb *kiocb, struct iov_iter *to)
 {
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
+	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb);
 	loff_t pos = 0;
 
 	return fuse_direct_io(&io, to, &pos, FUSE_DIO_CUSE);
···
 
 static ssize_t cuse_write_iter(struct kiocb *kiocb, struct iov_iter *from)
 {
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb->ki_filp);
+	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(kiocb);
 	loff_t pos = 0;
 	/*
 	 * No locking or generic_write_checks(), the server is

fs/fuse/dev.c

···
 	struct fuse_in *in;
 	unsigned reqsize;
 
-	if (task_active_pid_ns(current) != fc->pid_ns)
-		return -EIO;
-
  restart:
 	spin_lock(&fiq->waitq.lock);
 	err = -EAGAIN;
···
 
 	in = &req->in;
 	reqsize = in->h.len;
+
+	if (task_active_pid_ns(current) != fc->pid_ns) {
+		rcu_read_lock();
+		in->h.pid = pid_vnr(find_pid_ns(in->h.pid, fc->pid_ns));
+		rcu_read_unlock();
+	}
+
 	/* If request is too large, reply with an error and restart the read */
 	if (nbytes < reqsize) {
 		req->out.h.error = -EIO;
···
 	struct fuse_pqueue *fpq = &fud->pq;
 	struct fuse_req *req;
 	struct fuse_out_header oh;
-
-	if (task_active_pid_ns(current) != fc->pid_ns)
-		return -EIO;
 
 	if (nbytes < sizeof(struct fuse_out_header))
 		return -EINVAL;

fs/fuse/dir.c

···
 	return err;
 }
 
-int fuse_update_attributes(struct inode *inode, struct kstat *stat,
-			   struct file *file, bool *refreshed)
+static int fuse_update_get_attr(struct inode *inode, struct file *file,
+				struct kstat *stat)
 {
 	struct fuse_inode *fi = get_fuse_inode(inode);
-	int err;
-	bool r;
+	int err = 0;
 
 	if (time_before64(fi->i_time, get_jiffies_64())) {
-		r = true;
 		forget_all_cached_acls(inode);
 		err = fuse_do_getattr(inode, stat, file);
-	} else {
-		r = false;
-		err = 0;
-		if (stat) {
-			generic_fillattr(inode, stat);
-			stat->mode = fi->orig_i_mode;
-			stat->ino = fi->orig_ino;
-		}
+	} else if (stat) {
+		generic_fillattr(inode, stat);
+		stat->mode = fi->orig_i_mode;
+		stat->ino = fi->orig_ino;
 	}
 
-	if (refreshed != NULL)
-		*refreshed = r;
-
 	return err;
+}
+
+int fuse_update_attributes(struct inode *inode, struct file *file)
+{
+	return fuse_update_get_attr(inode, file, NULL);
 }
 
 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
···
 	if (!fuse_allow_current_process(fc))
 		return -EACCES;
 
-	return fuse_update_attributes(inode, stat, NULL, NULL);
+	return fuse_update_get_attr(inode, NULL, stat);
 }
 
 static const struct inode_operations fuse_dir_inode_operations = {

fs/fuse/file.c

···
 static size_t fuse_send_read(struct fuse_req *req, struct fuse_io_priv *io,
 			     loff_t pos, size_t count, fl_owner_t owner)
 {
-	struct file *file = io->file;
+	struct file *file = io->iocb->ki_filp;
 	struct fuse_file *ff = file->private_data;
 	struct fuse_conn *fc = ff->fc;
 
···
 
 static int fuse_do_readpage(struct file *file, struct page *page)
 {
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
+	struct kiocb iocb;
+	struct fuse_io_priv io;
 	struct inode *inode = page->mapping->host;
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_req *req;
···
 	req->num_pages = 1;
 	req->pages[0] = page;
 	req->page_descs[0].length = count;
+	init_sync_kiocb(&iocb, file);
+	io = (struct fuse_io_priv) FUSE_IO_PRIV_SYNC(&iocb);
 	num_read = fuse_send_read(req, &io, pos, count, NULL);
 	err = req->out.h.error;
 
···
 	if (fc->auto_inval_data ||
 	    (iocb->ki_pos + iov_iter_count(to) > i_size_read(inode))) {
 		int err;
-		err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL);
+		err = fuse_update_attributes(inode, iocb->ki_filp);
 		if (err)
 			return err;
 	}
···
 static size_t fuse_send_write(struct fuse_req *req, struct fuse_io_priv *io,
 			      loff_t pos, size_t count, fl_owner_t owner)
 {
-	struct file *file = io->file;
+	struct kiocb *iocb = io->iocb;
+	struct file *file = iocb->ki_filp;
 	struct fuse_file *ff = file->private_data;
 	struct fuse_conn *fc = ff->fc;
 	struct fuse_write_in *inarg = &req->misc.write.in;
 
 	fuse_write_fill(req, ff, pos, count);
 	inarg->flags = file->f_flags;
+	if (iocb->ki_flags & IOCB_DSYNC)
+		inarg->flags |= O_DSYNC;
+	if (iocb->ki_flags & IOCB_SYNC)
+		inarg->flags |= O_SYNC;
 	if (owner != NULL) {
 		inarg->write_flags |= FUSE_WRITE_LOCKOWNER;
 		inarg->lock_owner = fuse_lock_owner_id(fc, owner);
···
 	return ret;
 }
 
-static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file,
+static size_t fuse_send_write_pages(struct fuse_req *req, struct kiocb *iocb,
 				    struct inode *inode, loff_t pos,
 				    size_t count)
 {
 	size_t res;
 	unsigned offset;
 	unsigned i;
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
+	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
 
 	for (i = 0; i < req->num_pages; i++)
 		fuse_wait_on_page_writeback(inode, req->pages[i]->index);
···
 		     FUSE_MAX_PAGES_PER_REQ);
 }
 
-static ssize_t fuse_perform_write(struct file *file,
+static ssize_t fuse_perform_write(struct kiocb *iocb,
 				  struct address_space *mapping,
 				  struct iov_iter *ii, loff_t pos)
 {
···
 		} else {
 			size_t num_written;
 
-			num_written = fuse_send_write_pages(req, file, inode,
+			num_written = fuse_send_write_pages(req, iocb, inode,
 							    pos, count);
 			err = req->out.h.error;
 			if (!err) {
···
 
 	if (get_fuse_conn(inode)->writeback_cache) {
 		/* Update size (EOF optimization) and mode (SUID clearing) */
-		err = fuse_update_attributes(mapping->host, NULL, file, NULL);
+		err = fuse_update_attributes(mapping->host, file);
 		if (err)
 			return err;
 
···
 
 		pos += written;
 
-		written_buffered = fuse_perform_write(file, mapping, from, pos);
+		written_buffered = fuse_perform_write(iocb, mapping, from, pos);
 		if (written_buffered < 0) {
 			err = written_buffered;
 			goto out;
···
 		written += written_buffered;
 		iocb->ki_pos = pos + written_buffered;
 	} else {
-		written = fuse_perform_write(file, mapping, from, iocb->ki_pos);
+		written = fuse_perform_write(iocb, mapping, from, iocb->ki_pos);
 		if (written >= 0)
 			iocb->ki_pos += written;
 	}
 out:
 	current->backing_dev_info = NULL;
 	inode_unlock(inode);
+	if (written > 0)
+		written = generic_write_sync(iocb, written);
 
 	return written ? written : err;
 }
···
 {
 	int write = flags & FUSE_DIO_WRITE;
 	int cuse = flags & FUSE_DIO_CUSE;
-	struct file *file = io->file;
+	struct file *file = io->iocb->ki_filp;
 	struct inode *inode = file->f_mapping->host;
 	struct fuse_file *ff = file->private_data;
 	struct fuse_conn *fc = ff->fc;
···
 				  loff_t *ppos)
 {
 	ssize_t res;
-	struct file *file = io->file;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = file_inode(io->iocb->ki_filp);
 
 	if (is_bad_inode(inode))
 		return -EIO;
···
 
 static ssize_t fuse_direct_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb->ki_filp);
+	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
 	return __fuse_direct_read(&io, to, &iocb->ki_pos);
 }
 
 static ssize_t fuse_direct_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct file *file = iocb->ki_filp;
-	struct inode *inode = file_inode(file);
-	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(file);
+	struct inode *inode = file_inode(iocb->ki_filp);
+	struct fuse_io_priv io = FUSE_IO_PRIV_SYNC(iocb);
 	ssize_t res;
 
 	if (is_bad_inode(inode))
···
 	if ((fl->fl_flags & FL_CLOSE_POSIX) == FL_CLOSE_POSIX)
 		return 0;
 
-	if (pid && pid_nr == 0)
-		return -EOVERFLOW;
-
 	fuse_lk_fill(&args, file, fl, opcode, pid_nr, flock, &inarg);
 	err = fuse_simple_request(fc, &args);
 
···
 	return vfs_setpos(file, outarg.offset, inode->i_sb->s_maxbytes);
 
 fallback:
-	err = fuse_update_attributes(inode, NULL, file, NULL);
+	err = fuse_update_attributes(inode, file);
 	if (!err)
 		return generic_file_llseek(file, offset, whence);
 	else
···
 		break;
 	case SEEK_END:
 		inode_lock(inode);
-		retval = fuse_update_attributes(inode, NULL, file, NULL);
+		retval = fuse_update_attributes(inode, file);
 		if (!retval)
 			retval = generic_file_llseek(file, offset, whence);
 		inode_unlock(inode);
···
 	io->offset = offset;
 	io->write = (iov_iter_rw(iter) == WRITE);
 	io->err = 0;
-	io->file = file;
 	/*
 	 * By default, we want to optimize all I/Os with async request
 	 * submission to the client filesystem if supported.

fs/fuse/fuse_i.h

···
 	bool should_dirty;
 	int err;
 	struct kiocb *iocb;
-	struct file *file;
 	struct completion *done;
 	bool blocking;
 };
 
-#define FUSE_IO_PRIV_SYNC(f) \
+#define FUSE_IO_PRIV_SYNC(i) \
 {					\
 	.refcnt = KREF_INIT(1),		\
 	.async = 0,			\
-	.file = f,			\
+	.iocb = i,			\
 }
 
 /**
···
 
 void fuse_update_ctime(struct inode *inode);
 
-int fuse_update_attributes(struct inode *inode, struct kstat *stat,
-			   struct file *file, bool *refreshed);
+int fuse_update_attributes(struct inode *inode, struct file *file);
 
 void fuse_flush_writepages(struct inode *inode);