Commit a56834e0 authored by Stefan Roesch's avatar Stefan Roesch Committed by Jens Axboe
Browse files

io_uring: add fgetxattr and getxattr support 



This adds support to io_uring for the fgetxattr and getxattr API.

Signed-off-by: default avatarStefan Roesch <shr@fb.com>
Acked-by: default avatarChristian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20220323154420.3301504-5-shr@fb.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent e9621e2b

fs/io_uring.c

+129 −0
Original line number Diff line number Diff line
@@ -1223,6 +1223,10 @@ static const struct io_op_def io_op_defs[] = { 
		.needs_file = 1

	},

	[IORING_OP_SETXATTR] = {},

	[IORING_OP_FGETXATTR] = {

		.needs_file = 1

	},

	[IORING_OP_GETXATTR] = {},

};



/* requests with any of those set should undergo io_disarm_next() */
@@ -4224,6 +4228,119 @@ static void io_xattr_finish(struct io_kiocb *req, int ret) 
	io_req_complete(req, ret);

}



static int __io_getxattr_prep(struct io_kiocb *req,

			      const struct io_uring_sqe *sqe)

{

	struct io_xattr *ix = &req->xattr;

	const char __user *name;

	int ret;



	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))

		return -EINVAL;

	if (unlikely(sqe->ioprio))

		return -EINVAL;

	if (unlikely(req->flags & REQ_F_FIXED_FILE))

		return -EBADF;



	ix->filename = NULL;

	ix->ctx.kvalue = NULL;

	name = u64_to_user_ptr(READ_ONCE(sqe->addr));

	ix->ctx.cvalue = u64_to_user_ptr(READ_ONCE(sqe->addr2));

	ix->ctx.size = READ_ONCE(sqe->len);

	ix->ctx.flags = READ_ONCE(sqe->xattr_flags);



	if (ix->ctx.flags)

		return -EINVAL;



	ix->ctx.kname = kmalloc(sizeof(*ix->ctx.kname), GFP_KERNEL);

	if (!ix->ctx.kname)

		return -ENOMEM;



	ret = strncpy_from_user(ix->ctx.kname->name, name,

				sizeof(ix->ctx.kname->name));

	if (!ret || ret == sizeof(ix->ctx.kname->name))

		ret = -ERANGE;

	if (ret < 0) {

		kfree(ix->ctx.kname);

		return ret;

	}



	req->flags |= REQ_F_NEED_CLEANUP;

	return 0;

}



static int io_fgetxattr_prep(struct io_kiocb *req,

			     const struct io_uring_sqe *sqe)

{

	return __io_getxattr_prep(req, sqe);

}



static int io_getxattr_prep(struct io_kiocb *req,

			    const struct io_uring_sqe *sqe)

{

	struct io_xattr *ix = &req->xattr;

	const char __user *path;

	int ret;



	ret = __io_getxattr_prep(req, sqe);

	if (ret)

		return ret;



	path = u64_to_user_ptr(READ_ONCE(sqe->addr3));



	ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);

	if (IS_ERR(ix->filename)) {

		ret = PTR_ERR(ix->filename);

		ix->filename = NULL;

	}



	return ret;

}



static int io_fgetxattr(struct io_kiocb *req, unsigned int issue_flags)

{

	struct io_xattr *ix = &req->xattr;

	int ret;



	if (issue_flags & IO_URING_F_NONBLOCK)

		return -EAGAIN;



	ret = do_getxattr(mnt_user_ns(req->file->f_path.mnt),

			req->file->f_path.dentry,

			&ix->ctx);



	io_xattr_finish(req, ret);

	return 0;

}



static int io_getxattr(struct io_kiocb *req, unsigned int issue_flags)

{

	struct io_xattr *ix = &req->xattr;

	unsigned int lookup_flags = LOOKUP_FOLLOW;

	struct path path;

	int ret;



	if (issue_flags & IO_URING_F_NONBLOCK)

		return -EAGAIN;



retry:

	ret = filename_lookup(AT_FDCWD, ix->filename, lookup_flags, &path, NULL);

	if (!ret) {

		ret = do_getxattr(mnt_user_ns(path.mnt),

				path.dentry,

				&ix->ctx);



		path_put(&path);

		if (retry_estale(ret, lookup_flags)) {

			lookup_flags |= LOOKUP_REVAL;

			goto retry;

		}

	}



	io_xattr_finish(req, ret);

	return 0;

}



static int __io_setxattr_prep(struct io_kiocb *req,

			const struct io_uring_sqe *sqe)

{
@@ -7305,6 +7422,10 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
		return io_fsetxattr_prep(req, sqe);

	case IORING_OP_SETXATTR:

		return io_setxattr_prep(req, sqe);

	case IORING_OP_FGETXATTR:

		return io_fgetxattr_prep(req, sqe);

	case IORING_OP_GETXATTR:

		return io_getxattr_prep(req, sqe);

	}



	printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
@@ -7451,6 +7572,8 @@ static void io_clean_op(struct io_kiocb *req) 
			break;

		case IORING_OP_SETXATTR:

		case IORING_OP_FSETXATTR:

		case IORING_OP_GETXATTR:

		case IORING_OP_FGETXATTR:

			__io_xattr_finish(req);

			break;

		}
@@ -7615,6 +7738,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) 
	case IORING_OP_SETXATTR:

		ret = io_setxattr(req, issue_flags);

		break;

	case IORING_OP_FGETXATTR:

		ret = io_fgetxattr(req, issue_flags);

		break;

	case IORING_OP_GETXATTR:

		ret = io_getxattr(req, issue_flags);

		break;

	default:

		ret = -EINVAL;

		break;

include/uapi/linux/io_uring.h

+2 −0
Original line number Diff line number Diff line
@@ -149,6 +149,8 @@ enum { 
	IORING_OP_MSG_RING,

	IORING_OP_FSETXATTR,

	IORING_OP_SETXATTR,

	IORING_OP_FGETXATTR,

	IORING_OP_GETXATTR,



	/* this goes last, obviously */

	IORING_OP_LAST,