io_uring: call statx directly

Calling statx directly both simplifies the interface and avoids potential
incompatibilities between sync and async invokations.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 2d86bd7..de6547e 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -482,7 +482,7 @@ struct io_statx {
        int                             dfd;
        unsigned int                    mask;
        unsigned int                    flags;
-       struct filename                 *filename;
+       const char __user               *filename;
        struct statx __user             *buffer;
 };
 
@@ -3376,43 +3376,23 @@ static int io_fadvise(struct io_kiocb *req, bool force_nonblock)
 
 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
-       const char __user *fname;
-       unsigned lookup_flags;
-       int ret;
-
        if (sqe->ioprio || sqe->buf_index)
                return -EINVAL;
        if (req->flags & REQ_F_FIXED_FILE)
                return -EBADF;
-       if (req->flags & REQ_F_NEED_CLEANUP)
-               return 0;
 
        req->statx.dfd = READ_ONCE(sqe->fd);
        req->statx.mask = READ_ONCE(sqe->len);
-       fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
+       req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
        req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
        req->statx.flags = READ_ONCE(sqe->statx_flags);
 
-       if (vfs_stat_set_lookup_flags(&lookup_flags, req->statx.flags))
-               return -EINVAL;
-
-       req->statx.filename = getname_flags(fname, lookup_flags, NULL);
-       if (IS_ERR(req->statx.filename)) {
-               ret = PTR_ERR(req->statx.filename);
-               req->statx.filename = NULL;
-               return ret;
-       }
-
-       req->flags |= REQ_F_NEED_CLEANUP;
        return 0;
 }
 
 static int io_statx(struct io_kiocb *req, bool force_nonblock)
 {
        struct io_statx *ctx = &req->statx;
-       unsigned lookup_flags;
-       struct path path;
-       struct kstat stat;
        int ret;
 
        if (force_nonblock) {
@@ -3422,29 +3402,9 @@ static int io_statx(struct io_kiocb *req, bool force_nonblock)
                return -EAGAIN;
        }
 
-       if (vfs_stat_set_lookup_flags(&lookup_flags, ctx->flags))
-               return -EINVAL;
-
-retry:
-       /* filename_lookup() drops it, keep a reference */
-       ctx->filename->refcnt++;
-
-       ret = filename_lookup(ctx->dfd, ctx->filename, lookup_flags, &path,
-                               NULL);
-       if (ret)
-               goto err;
+       ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
+                      ctx->buffer);
 
-       ret = vfs_getattr(&path, &stat, ctx->mask, ctx->flags);
-       path_put(&path);
-       if (retry_estale(ret, lookup_flags)) {
-               lookup_flags |= LOOKUP_REVAL;
-               goto retry;
-       }
-       if (!ret)
-               ret = cp_statx(&stat, ctx->buffer);
-err:
-       putname(ctx->filename);
-       req->flags &= ~REQ_F_NEED_CLEANUP;
        if (ret < 0)
                req_set_fail_links(req);
        io_cqring_add_event(req, ret);
@@ -5196,8 +5156,6 @@ static void io_cleanup_req(struct io_kiocb *req)
                break;
        case IORING_OP_OPENAT:
        case IORING_OP_OPENAT2:
-       case IORING_OP_STATX:
-               putname(req->open.filename);
                break;
        case IORING_OP_SPLICE:
        case IORING_OP_TEE: