// SPDX-License-Identifier: GPL-2.0#include <linux/kernel.h>#include <linux/errno.h>#include <linux/fs.h>#include <linux/file.h>#include <linux/fdtable.h>#include <linux/fsnotify.h>#include <linux/namei.h>#include <linux/io_uring.h> #include <uapi/linux/io_uring.h> #include "../fs/internal.h" #include "io_uring.h"#include "rsrc.h"#include "openclose.h" struct io_open {	struct file			*file;	int				dfd;	u32				file_slot;	struct filename			*filename;	struct open_how			how;	unsigned long			nofile;}; struct io_close {	struct file			*file;	int				fd;	u32				file_slot;}; static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe){	struct io_open *open = io_kiocb_to_cmd(req, struct io_open);	const char __user *fname;	int ret; 	if (unlikely(sqe->buf_index))		return -EINVAL;	if (unlikely(req->flags & REQ_F_FIXED_FILE))		return -EBADF; 	/* open.how should be already initialised */	if (!(open->how.flags & O_PATH) && force_o_largefile())		open->how.flags |= O_LARGEFILE; 	open->dfd = READ_ONCE(sqe->fd);	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));	open->filename = getname(fname);	if (IS_ERR(open->filename)) {		ret = PTR_ERR(open->filename);		open->filename = NULL;		return ret;	} 	open->file_slot = READ_ONCE(sqe->file_index);	if (open->file_slot && (open->how.flags & O_CLOEXEC))		return -EINVAL; 	open->nofile = rlimit(RLIMIT_NOFILE);	req->flags |= REQ_F_NEED_CLEANUP;	return 0;} int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe){	struct io_open *open = io_kiocb_to_cmd(req, struct io_open);	u64 mode = READ_ONCE(sqe->len);	u64 flags = READ_ONCE(sqe->open_flags); 	open->how = build_open_how(flags, mode);	return __io_openat_prep(req, sqe);} int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe){	struct io_open *open = io_kiocb_to_cmd(req, struct io_open);	struct open_how __user *how;	size_t len;	int ret; 	how = u64_to_user_ptr(READ_ONCE(sqe->addr2));	len = READ_ONCE(sqe->len);	if (len < OPEN_HOW_SIZE_VER0)		return -EINVAL; 	ret = copy_struct_from_user(&open->how, sizeof(open->how), how, len);	if (ret)		return ret; 	return __io_openat_prep(req, sqe);} int io_openat2(struct io_kiocb *req, unsigned int issue_flags){	struct io_open *open = io_kiocb_to_cmd(req, struct io_open);	struct open_flags op;	struct file *file;	bool resolve_nonblock, nonblock_set;	bool fixed = !!open->file_slot;	int ret; 	ret = build_open_flags(&open->how, &op);	if (ret)		goto err;	nonblock_set = op.open_flag & O_NONBLOCK;	resolve_nonblock = open->how.resolve & RESOLVE_CACHED;	if (issue_flags & IO_URING_F_NONBLOCK) {		/*		 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,		 * it'll always -EAGAIN		 */		if (open->how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))			return -EAGAIN;		op.lookup_flags |= LOOKUP_CACHED;		op.open_flag |= O_NONBLOCK;	} 	if (!fixed) {		ret = __get_unused_fd_flags(open->how.flags, open->nofile);		if (ret < 0)			goto err;	} 	file = do_filp_open(open->dfd, open->filename, &op);	if (IS_ERR(file)) {		/*		 * We could hang on to this 'fd' on retrying, but seems like		 * marginal gain for something that is now known to be a slower		 * path. So just put it, and we'll get a new one when we retry.		 */		if (!fixed)			put_unused_fd(ret); 		ret = PTR_ERR(file);		/* only retry if RESOLVE_CACHED wasn't already set by application */		if (ret == -EAGAIN &&		    (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))			return -EAGAIN;		goto err;	} 	if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)		file->f_flags &= ~O_NONBLOCK;	fsnotify_open(file); 	if (!fixed)		fd_install(ret, file);	else		ret = io_fixed_fd_install(req, issue_flags, file,						open->file_slot);err:	putname(open->filename);	req->flags &= ~REQ_F_NEED_CLEANUP;	if (ret < 0)		req_set_fail(req);	io_req_set_res(req, ret, 0);	return IOU_OK;} int io_openat(struct io_kiocb *req, unsigned int issue_flags){	return io_openat2(req, issue_flags);} void io_open_cleanup(struct io_kiocb *req){	struct io_open *open = io_kiocb_to_cmd(req, struct io_open); 	if (open->filename)		putname(open->filename);} int __io_close_fixed(struct io_ring_ctx *ctx, unsigned int issue_flags,		     unsigned int offset){	int ret; 	io_ring_submit_lock(ctx, issue_flags);	ret = io_fixed_fd_remove(ctx, offset);	io_ring_submit_unlock(ctx, issue_flags); 	return ret;} static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags){	struct io_close *close = io_kiocb_to_cmd(req, struct io_close); 	return __io_close_fixed(req->ctx, issue_flags, close->file_slot - 1);} int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe){	struct io_close *close = io_kiocb_to_cmd(req, struct io_close); 	if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index)		return -EINVAL;	if (req->flags & REQ_F_FIXED_FILE)		return -EBADF; 	close->fd = READ_ONCE(sqe->fd);	close->file_slot = READ_ONCE(sqe->file_index);	if (close->file_slot && close->fd)		return -EINVAL; 	return 0;} int io_close(struct io_kiocb *req, unsigned int issue_flags){	struct files_struct *files = current->files;	struct io_close *close = io_kiocb_to_cmd(req, struct io_close);	struct fdtable *fdt;	struct file *file;	int ret = -EBADF; 	if (close->file_slot) {		ret = io_close_fixed(req, issue_flags);		goto err;	} 	spin_lock(&files->file_lock);	fdt = files_fdtable(files);	if (close->fd >= fdt->max_fds) {		spin_unlock(&files->file_lock);		goto err;	}	file = rcu_dereference_protected(fdt->fd[close->fd],			lockdep_is_held(&files->file_lock));	if (!file || io_is_uring_fops(file)) {		spin_unlock(&files->file_lock);		goto err;	} 	/* if the file has a flush method, be safe and punt to async */	if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {		spin_unlock(&files->file_lock);		return -EAGAIN;	} 	file = __close_fd_get_file(close->fd);	spin_unlock(&files->file_lock);	if (!file)		goto err; 	/* No ->flush() or already async, safely close from here */	ret = filp_close(file, current->files);err:	if (ret < 0)		req_set_fail(req);	io_req_set_res(req, ret, 0);	return IOU_OK;}