{
struct io_uring_buf_ring *br;
struct page **pages;
- int nr_pages;
+ int i, nr_pages;
pages = io_pin_pages(reg->ring_addr,
flex_array_size(br, bufs, reg->ring_entries),
if (IS_ERR(pages))
return PTR_ERR(pages);
+ /*
+ * Apparently some 32-bit boxes (ARM) will return highmem pages,
+ * which then need to be mapped. We could support that, but it'd
+ * complicate the code and slowdown the common cases quite a bit.
+ * So just error out, returning -EINVAL just like we did on kernels
+ * that didn't support mapped buffer rings.
+ */
+ for (i = 0; i < nr_pages; i++)
+ if (PageHighMem(pages[i]))
+ goto error_unpin;
+
br = page_address(pages[0]);
#ifdef SHM_COLOUR
/*
* should use IOU_PBUF_RING_MMAP instead, and liburing will handle
* this transparently.
*/
- if ((reg->ring_addr | (unsigned long) br) & (SHM_COLOUR - 1)) {
- int i;
-
- for (i = 0; i < nr_pages; i++)
- unpin_user_page(pages[i]);
- return -EINVAL;
- }
+ if ((reg->ring_addr | (unsigned long) br) & (SHM_COLOUR - 1))
+ goto error_unpin;
#endif
bl->buf_pages = pages;
bl->buf_nr_pages = nr_pages;
bl->is_mapped = 1;
bl->is_mmap = 0;
return 0;
+error_unpin:
+ for (i = 0; i < nr_pages; i++)
+ unpin_user_page(pages[i]);
+ kvfree(pages);
+ return -EINVAL;
}
static int io_alloc_pbuf_ring(struct io_uring_buf_reg *reg,