+#if defined(HAVE_VFS_RW_ITERATE)
+static ssize_t
+zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from)
+{
+ size_t count;
+ ssize_t ret;
+ uio_seg_t seg = UIO_USERSPACE;
+
+#ifndef HAVE_GENERIC_WRITE_CHECKS_KIOCB
+ struct file *file = kiocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ struct inode *ip = mapping->host;
+ int isblk = S_ISBLK(ip->i_mode);
+
+ count = iov_iter_count(from);
+ ret = generic_write_checks(file, &kiocb->ki_pos, &count, isblk);
+ if (ret)
+ return (ret);
+#else
+ /*
+ * XXX - ideally this check should be in the same lock region with
+ * write operations, so that there's no TOCTTOU race when doing
+ * append and someone else grow the file.
+ */
+ ret = generic_write_checks(kiocb, from);
+ if (ret <= 0)
+ return (ret);
+ count = ret;
+#endif
+
+ if (from->type & ITER_KVEC)
+ seg = UIO_SYSSPACE;
+ if (from->type & ITER_BVEC)
+ seg = UIO_BVEC;
+
+ ret = zpl_iter_write_common(kiocb, from->iov, from->nr_segs,
+ count, seg, from->iov_offset);
+ if (ret > 0)
+ iov_iter_advance(from, ret);
+
+ return (ret);
+}
+#else
+static ssize_t
+zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct file *file = kiocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ struct inode *ip = mapping->host;
+ int isblk = S_ISBLK(ip->i_mode);
+ size_t count;
+ ssize_t ret;
+
+ ret = generic_segment_checks(iovp, &nr_segs, &count, VERIFY_READ);
+ if (ret)
+ return (ret);
+
+ ret = generic_write_checks(file, &pos, &count, isblk);
+ if (ret)
+ return (ret);
+
+ return (zpl_iter_write_common(kiocb, iovp, nr_segs, count,
+ UIO_USERSPACE, 0));
+}
+#endif /* HAVE_VFS_RW_ITERATE */
+
+#if defined(HAVE_VFS_RW_ITERATE)
+static ssize_t
+zpl_direct_IO_impl(int rw, struct kiocb *kiocb, struct iov_iter *iter)
+{
+ if (rw == WRITE)
+ return (zpl_iter_write(kiocb, iter));
+ else
+ return (zpl_iter_read(kiocb, iter));
+}
+#if defined(HAVE_VFS_DIRECT_IO_ITER)
+static ssize_t
+zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter)
+{
+ return (zpl_direct_IO_impl(iov_iter_rw(iter), kiocb, iter));
+}
+#elif defined(HAVE_VFS_DIRECT_IO_ITER_OFFSET)
+static ssize_t
+zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter, loff_t pos)
+{
+ ASSERT3S(pos, ==, kiocb->ki_pos);
+ return (zpl_direct_IO_impl(iov_iter_rw(iter), kiocb, iter));
+}
+#elif defined(HAVE_VFS_DIRECT_IO_ITER_RW_OFFSET)
+static ssize_t
+zpl_direct_IO(int rw, struct kiocb *kiocb, struct iov_iter *iter, loff_t pos)
+{
+ ASSERT3S(pos, ==, kiocb->ki_pos);
+ return (zpl_direct_IO_impl(rw, kiocb, iter));
+}
+#else
+#error "Unknown direct IO interface"
+#endif
+
+#else
+
+#if defined(HAVE_VFS_DIRECT_IO_IOVEC)
+static ssize_t
+zpl_direct_IO(int rw, struct kiocb *kiocb, const struct iovec *iovp,
+ loff_t pos, unsigned long nr_segs)
+{
+ if (rw == WRITE)
+ return (zpl_aio_write(kiocb, iovp, nr_segs, pos));
+ else
+ return (zpl_aio_read(kiocb, iovp, nr_segs, pos));
+}
+#else
+#error "Unknown direct IO interface"
+#endif
+
+#endif /* HAVE_VFS_RW_ITERATE */
+
+static loff_t
+zpl_llseek(struct file *filp, loff_t offset, int whence)
+{
+#if defined(SEEK_HOLE) && defined(SEEK_DATA)
+ fstrans_cookie_t cookie;
+
+ if (whence == SEEK_DATA || whence == SEEK_HOLE) {
+ struct inode *ip = filp->f_mapping->host;
+ loff_t maxbytes = ip->i_sb->s_maxbytes;
+ loff_t error;
+
+ spl_inode_lock_shared(ip);
+ cookie = spl_fstrans_mark();
+ error = -zfs_holey(ip, whence, &offset);
+ spl_fstrans_unmark(cookie);
+ if (error == 0)
+ error = lseek_execute(filp, ip, offset, maxbytes);
+ spl_inode_unlock_shared(ip);
+
+ return (error);
+ }
+#endif /* SEEK_HOLE && SEEK_DATA */
+
+ return (generic_file_llseek(filp, offset, whence));
+}
+