On 6/24/21 12:14 PM, Dmitry Kadashev wrote: > IORING_OP_SYMLINKAT behaves like symlinkat(2) and takes the same flags > and arguments. Reviewed-by: Pavel Begunkov <asml.silence@xxxxxxxxx> > > Suggested-by: Christian Brauner <christian.brauner@xxxxxxxxxx> > Link: https://lore.kernel.org/io-uring/20210514145259.wtl4xcsp52woi6ab@wittgenstein/ > Signed-off-by: Dmitry Kadashev <dkadashev@xxxxxxxxx> > Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx> > --- > fs/internal.h | 1 + > fs/io_uring.c | 66 +++++++++++++++++++++++++++++++++++ > fs/namei.c | 3 +- > include/uapi/linux/io_uring.h | 1 + > 4 files changed, 69 insertions(+), 2 deletions(-) > > diff --git a/fs/internal.h b/fs/internal.h > index 207a455e32d3..3b3954214385 100644 > --- a/fs/internal.h > +++ b/fs/internal.h > @@ -78,6 +78,7 @@ int may_linkat(struct user_namespace *mnt_userns, struct path *link); > int do_renameat2(int olddfd, struct filename *oldname, int newdfd, > struct filename *newname, unsigned int flags); > int do_mkdirat(int dfd, struct filename *name, umode_t mode); > +int do_symlinkat(struct filename *from, int newdfd, struct filename *to); > > /* > * namespace.c > diff --git a/fs/io_uring.c b/fs/io_uring.c > index 7aa08ed78452..c161f06a3cea 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -680,6 +680,13 @@ struct io_mkdir { > struct filename *filename; > }; > > +struct io_symlink { > + struct file *file; > + int new_dfd; > + struct filename *oldpath; > + struct filename *newpath; > +}; > + > struct io_completion { > struct file *file; > struct list_head list; > @@ -833,6 +840,7 @@ struct io_kiocb { > struct io_rename rename; > struct io_unlink unlink; > struct io_mkdir mkdir; > + struct io_symlink symlink; > /* use only after cleaning per-op data, see io_clean_op() */ > struct io_completion compl; > }; > @@ -1048,6 +1056,7 @@ static const struct io_op_def io_op_defs[] = { > [IORING_OP_RENAMEAT] = {}, > [IORING_OP_UNLINKAT] = {}, > [IORING_OP_MKDIRAT] = {}, > + [IORING_OP_SYMLINKAT] = {}, > }; > > static bool io_disarm_next(struct io_kiocb *req); > @@ -3599,6 +3608,54 @@ static int io_mkdirat(struct io_kiocb *req, int issue_flags) > return 0; > } > > +static int io_symlinkat_prep(struct io_kiocb *req, > + const struct io_uring_sqe *sqe) > +{ > + struct io_symlink *sl = &req->symlink; > + const char __user *oldpath, *newpath; > + > + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) > + return -EINVAL; > + if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index) > + return -EINVAL; > + if (unlikely(req->flags & REQ_F_FIXED_FILE)) > + return -EBADF; > + > + sl->new_dfd = READ_ONCE(sqe->fd); > + oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr)); > + newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2)); > + > + sl->oldpath = getname(oldpath); > + if (IS_ERR(sl->oldpath)) > + return PTR_ERR(sl->oldpath); > + > + sl->newpath = getname(newpath); > + if (IS_ERR(sl->newpath)) { > + putname(sl->oldpath); > + return PTR_ERR(sl->newpath); > + } > + > + req->flags |= REQ_F_NEED_CLEANUP; > + return 0; > +} > + > +static int io_symlinkat(struct io_kiocb *req, int issue_flags) > +{ > + struct io_symlink *sl = &req->symlink; > + int ret; > + > + if (issue_flags & IO_URING_F_NONBLOCK) > + return -EAGAIN; > + > + ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath); > + > + req->flags &= ~REQ_F_NEED_CLEANUP; > + if (ret < 0) > + req_set_fail(req); > + io_req_complete(req, ret); > + return 0; > +} > + > static int io_shutdown_prep(struct io_kiocb *req, > const struct io_uring_sqe *sqe) > { > @@ -6009,6 +6066,8 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) > return io_unlinkat_prep(req, sqe); > case IORING_OP_MKDIRAT: > return io_mkdirat_prep(req, sqe); > + case IORING_OP_SYMLINKAT: > + return io_symlinkat_prep(req, sqe); > } > > printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", > @@ -6173,6 +6232,10 @@ static void io_clean_op(struct io_kiocb *req) > case IORING_OP_MKDIRAT: > putname(req->mkdir.filename); > break; > + case IORING_OP_SYMLINKAT: > + putname(req->symlink.oldpath); > + putname(req->symlink.newpath); > + break; > } > } > if ((req->flags & REQ_F_POLLED) && req->apoll) { > @@ -6304,6 +6367,9 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) > case IORING_OP_MKDIRAT: > ret = io_mkdirat(req, issue_flags); > break; > + case IORING_OP_SYMLINKAT: > + ret = io_symlinkat(req, issue_flags); > + break; > default: > ret = -EINVAL; > break; > diff --git a/fs/namei.c b/fs/namei.c > index f99de6e294ad..f5b0379d2f8c 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -4208,8 +4208,7 @@ int vfs_symlink(struct user_namespace *mnt_userns, struct inode *dir, > } > EXPORT_SYMBOL(vfs_symlink); > > -static int do_symlinkat(struct filename *from, int newdfd, > - struct filename *to) > +int do_symlinkat(struct filename *from, int newdfd, struct filename *to) > { > int error; > struct dentry *dentry; > diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h > index 49a24a149eeb..796f37ab4ce3 100644 > --- a/include/uapi/linux/io_uring.h > +++ b/include/uapi/linux/io_uring.h > @@ -138,6 +138,7 @@ enum { > IORING_OP_RENAMEAT, > IORING_OP_UNLINKAT, > IORING_OP_MKDIRAT, > + IORING_OP_SYMLINKAT, > > /* this goes last, obviously */ > IORING_OP_LAST, > -- Pavel Begunkov
