io_uring: use vmap() for ring mapping

This is the last holdout which does odd page checking, convert it to
vmap just like what is done for the non-mmap path.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index fba68c37a77dc58f432632fbba3f1713d0e69773..ef8f1c6ee2539b23877a28e9e129c0d187bb40f9 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -63,7 +63,6 @@
 #include <linux/sched/mm.h>
 #include <linux/uaccess.h>
 #include <linux/nospec.h>
-#include <linux/highmem.h>
 #include <linux/fsnotify.h>
 #include <linux/fadvise.h>
 #include <linux/task_work.h>
@@ -2657,7 +2656,7 @@ static void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
        struct page **page_array;
        unsigned int nr_pages;
        void *page_addr;
-       int ret, i, pinned;
+       int ret, pinned;
 
        *npages = 0;
 
@@ -2679,34 +2678,13 @@ static void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
                goto free_pages;
        }
 
-       page_addr = page_address(page_array[0]);
-       for (i = 0; i < nr_pages; i++) {
-               ret = -EINVAL;
-
-               /*
-                * Can't support mapping user allocated ring memory on 32-bit
-                * archs where it could potentially reside in highmem. Just
-                * fail those with -EINVAL, just like we did on kernels that
-                * didn't support this feature.
-                */
-               if (PageHighMem(page_array[i]))
-                       goto free_pages;
-
-               /*
-                * No support for discontig pages for now, should either be a
-                * single normal page, or a huge page. Later on we can add
-                * support for remapping discontig pages, for now we will
-                * just fail them with EINVAL.
-                */
-               if (page_address(page_array[i]) != page_addr)
-                       goto free_pages;
-               page_addr += PAGE_SIZE;
+       page_addr = vmap(page_array, nr_pages, VM_MAP, PAGE_KERNEL);
+       if (page_addr) {
+               *pages = page_array;
+               *npages = nr_pages;
+               return page_addr;
        }
-
-       *pages = page_array;
-       *npages = nr_pages;
-       return page_to_virt(page_array[0]);
-
+       ret = -ENOMEM;
 free_pages:
        io_pages_free(&page_array, pinned > 0 ? pinned : 0);
        return ERR_PTR(ret);
@@ -2736,6 +2714,8 @@ static void io_rings_free(struct io_ring_ctx *ctx)
                ctx->n_ring_pages = 0;
                io_pages_free(&ctx->sqe_pages, ctx->n_sqe_pages);
                ctx->n_sqe_pages = 0;
+               vunmap(ctx->rings);
+               vunmap(ctx->sq_sqes);
        }
 
        ctx->rings = NULL;