soc: fsl: dpio: avoid stack usage warning

A 1024 byte variable on the stack will warn on any 32-bit architecture
during compile-testing, and is generally a bad idea anyway:

fsl/dpio/dpio-service.c: In function 'dpaa2_io_service_enqueue_multiple_desc_fq':
fsl/dpio/dpio-service.c:495:1: error: the frame size of 1032 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

There are currently no callers of this function, so I cannot tell whether
dynamic memory allocation is allowed once callers are added. Change
it to kcalloc for now, if anyone gets a warning about calling this in
atomic context after they start using it, they can fix it later.

Link: https://lore.kernel.org/r/20200408185834.434784-1-arnd@arndb.de
Fixes: 9d98809711ae ("soc: fsl: dpio: Adding QMAN multiple enqueue interface")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
index cd4f641..bcdcd3e 100644 (file)
--- a/drivers/soc/fsl/dpio/dpio-service.c
+++ b/drivers/soc/fsl/dpio/dpio-service.c
@@ -478,12 +478,18 @@ int dpaa2_io_service_enqueue_multiple_desc_fq(struct dpaa2_io *d,
                                const struct dpaa2_fd *fd,
                                int nb)
 {
-       int i;
-       struct qbman_eq_desc ed[32];
+       struct qbman_eq_desc *ed;
+       int i, ret;
+
+       ed = kcalloc(sizeof(struct qbman_eq_desc), 32, GFP_KERNEL);
+       if (!ed)
+               return -ENOMEM;
 
        d = service_select(d);
-       if (!d)
-               return -ENODEV;
+       if (!d) {
+               ret = -ENODEV;
+               goto out;
+       }
 
        for (i = 0; i < nb; i++) {
                qbman_eq_desc_clear(&ed[i]);
@@ -491,7 +497,10 @@ int dpaa2_io_service_enqueue_multiple_desc_fq(struct dpaa2_io *d,
                qbman_eq_desc_set_fq(&ed[i], fqid[i]);
        }
 
-       return qbman_swp_enqueue_multiple_desc(d->swp, &ed[0], fd, nb);
+       ret = qbman_swp_enqueue_multiple_desc(d->swp, &ed[0], fd, nb);
+out:
+       kfree(ed);
+       return ret;
 }
 EXPORT_SYMBOL(dpaa2_io_service_enqueue_multiple_desc_fq);