Commit e9621e2b authored by Stefan Roesch's avatar Stefan Roesch Committed by Jens Axboe
Browse files

io_uring: add fsetxattr and setxattr support 



This adds support to io_uring for the fsetxattr and setxattr API.

Signed-off-by: default avatarStefan Roesch <shr@fb.com>
Acked-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20220323154420.3301504-4-shr@fb.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c975cad9

fs/io_uring.c

+165 −0
Original line number Diff line number Diff line
@@ -80,6 +80,7 @@ 
#include <linux/io_uring.h>

#include <linux/audit.h>

#include <linux/security.h>

#include <linux/xattr.h>



#define CREATE_TRACE_POINTS

#include <trace/events/io_uring.h>
@@ -779,6 +780,12 @@ struct io_async_rw { 
	struct wait_page_queue		wpq;

};



struct io_xattr {

	struct file			*file;

	struct xattr_ctx		ctx;

	struct filename			*filename;

};



enum {

	REQ_F_FIXED_FILE_BIT	= IOSQE_FIXED_FILE_BIT,

	REQ_F_IO_DRAIN_BIT	= IOSQE_IO_DRAIN_BIT,
@@ -943,6 +950,7 @@ struct io_kiocb { 
		struct io_symlink	symlink;

		struct io_hardlink	hardlink;

		struct io_msg		msg;

		struct io_xattr		xattr;

	};



	u8				opcode;
@@ -1211,6 +1219,10 @@ static const struct io_op_def io_op_defs[] = { 
	[IORING_OP_MSG_RING] = {

		.needs_file		= 1,

	},

	[IORING_OP_FSETXATTR] = {

		.needs_file = 1

	},

	[IORING_OP_SETXATTR] = {},

};



/* requests with any of those set should undergo io_disarm_next() */
@@ -4190,6 +4202,144 @@ static int io_renameat(struct io_kiocb *req, unsigned int issue_flags) 
	return 0;

}



static inline void __io_xattr_finish(struct io_kiocb *req)

{

	struct io_xattr *ix = &req->xattr;



	if (ix->filename)

		putname(ix->filename);



	kfree(ix->ctx.kname);

	kvfree(ix->ctx.kvalue);

}



static void io_xattr_finish(struct io_kiocb *req, int ret)

{

	req->flags &= ~REQ_F_NEED_CLEANUP;



	__io_xattr_finish(req);

	if (ret < 0)

		req_set_fail(req);



	io_req_complete(req, ret);

}



static int __io_setxattr_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;

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

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

	ix->ctx.kvalue = NULL;

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

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



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

	if (!ix->ctx.kname)

		return -ENOMEM;



	ret = setxattr_copy(name, &ix->ctx);

	if (ret) {

		kfree(ix->ctx.kname);

		return ret;

	}



	req->flags |= REQ_F_NEED_CLEANUP;

	return 0;

}



static int io_setxattr_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_setxattr_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_fsetxattr_prep(struct io_kiocb *req,

			const struct io_uring_sqe *sqe)

{

	return __io_setxattr_prep(req, sqe);

}



static int __io_setxattr(struct io_kiocb *req, unsigned int issue_flags,

			struct path *path)

{

	struct io_xattr *ix = &req->xattr;

	int ret;



	ret = mnt_want_write(path->mnt);

	if (!ret) {

		ret = do_setxattr(mnt_user_ns(path->mnt), path->dentry, &ix->ctx);

		mnt_drop_write(path->mnt);

	}



	return ret;

}



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

{

	int ret;



	if (issue_flags & IO_URING_F_NONBLOCK)

		return -EAGAIN;



	ret = __io_setxattr(req, issue_flags, &req->file->f_path);

	io_xattr_finish(req, ret);



	return 0;

}



static int io_setxattr(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 = __io_setxattr(req, issue_flags, &path);

		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_unlinkat_prep(struct io_kiocb *req,

			    const struct io_uring_sqe *sqe)

{
@@ -7151,6 +7301,10 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
		return io_linkat_prep(req, sqe);

	case IORING_OP_MSG_RING:

		return io_msg_ring_prep(req, sqe);

	case IORING_OP_FSETXATTR:

		return io_fsetxattr_prep(req, sqe);

	case IORING_OP_SETXATTR:

		return io_setxattr_prep(req, sqe);

	}



	printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
@@ -7295,6 +7449,10 @@ static void io_clean_op(struct io_kiocb *req) 
			if (req->statx.filename)

				putname(req->statx.filename);

			break;

		case IORING_OP_SETXATTR:

		case IORING_OP_FSETXATTR:

			__io_xattr_finish(req);

			break;

		}

	}

	if ((req->flags & REQ_F_POLLED) && req->apoll) {
@@ -7451,6 +7609,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) 
	case IORING_OP_MSG_RING:

		ret = io_msg_ring(req, issue_flags);

		break;

	case IORING_OP_FSETXATTR:

		ret = io_fsetxattr(req, issue_flags);

		break;

	case IORING_OP_SETXATTR:

		ret = io_setxattr(req, issue_flags);

		break;

	default:

		ret = -EINVAL;

		break;
@@ -12012,6 +12176,7 @@ static int __init io_uring_init(void) 
	BUILD_BUG_SQE_ELEM(42, __u16,  personality);

	BUILD_BUG_SQE_ELEM(44, __s32,  splice_fd_in);

	BUILD_BUG_SQE_ELEM(44, __u32,  file_index);

	BUILD_BUG_SQE_ELEM(48, __u64,  addr3);



	BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=

		     sizeof(struct io_uring_rsrc_update));

include/uapi/linux/io_uring.h

+5 −1
Original line number Diff line number Diff line
@@ -45,6 +45,7 @@ struct io_uring_sqe { 
		__u32		rename_flags;

		__u32		unlink_flags;

		__u32		hardlink_flags;

		__u32		xattr_flags;

	};

	__u64	user_data;	/* data to be passed back at completion time */

	/* pack this to avoid bogus arm OABI complaints */
@@ -60,7 +61,8 @@ struct io_uring_sqe { 
		__s32	splice_fd_in;

		__u32	file_index;

	};

	__u64	__pad2[2];

	__u64	addr3;

	__u64	__pad2[1];

};



enum {
@@ -145,6 +147,8 @@ enum { 
	IORING_OP_SYMLINKAT,

	IORING_OP_LINKAT,

	IORING_OP_MSG_RING,

	IORING_OP_FSETXATTR,

	IORING_OP_SETXATTR,



	/* this goes last, obviously */

	IORING_OP_LAST,