io_uring: change ring size calculation for CQE32

This changes the function rings_size to take large CQE's into account.

Co-developed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220426182134.136504-4-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index da91723..279ccf6 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -9994,8 +9994,8 @@ static void *io_mem_alloc(size_t size)
        return (void *) __get_free_pages(gfp, get_order(size));
 }
 
-static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
-                               size_t *sq_offset)
+static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries,
+                               unsigned int cq_entries, size_t *sq_offset)
 {
        struct io_rings *rings;
        size_t off, sq_array_size;
@@ -10003,6 +10003,10 @@ static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
        off = struct_size(rings, cqes, cq_entries);
        if (off == SIZE_MAX)
                return SIZE_MAX;
+       if (ctx->flags & IORING_SETUP_CQE32) {
+               if (check_shl_overflow(off, 1, &off))
+                       return SIZE_MAX;
+       }
 
 #ifdef CONFIG_SMP
        off = ALIGN(off, SMP_CACHE_BYTES);
@@ -11684,7 +11688,7 @@ static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx,
        ctx->sq_entries = p->sq_entries;
        ctx->cq_entries = p->cq_entries;
 
-       size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
+       size = rings_size(ctx, p->sq_entries, p->cq_entries, &sq_array_offset);
        if (size == SIZE_MAX)
                return -EOVERFLOW;