[PATCH v2] tools/testing/nvdimm: Align test resources to 128M

From: Dan Williams
Date: Wed Dec 05 2018 - 17:28:34 EST


In preparation for libnvdimm growing new restrictions to detect section
conflicts between persistent memory regions, enable nfit_test to
allocate aligned resources. Use a gen_pool to allocate nfit_test's fake
resources in a separate address space from the virtual translation of
the same.

Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Tested-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
Changes in v2:
* Fix intermittent crash from stale vmalloc() alias usage (Vishal)

tools/testing/nvdimm/test/nfit.c | 35 +++++++++++++++++++++++++++++++++--
1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index 01ec04bf91b5..6c16ac36d482 100644
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -15,6 +15,7 @@
#include <linux/dma-mapping.h>
#include <linux/workqueue.h>
#include <linux/libnvdimm.h>
+#include <linux/genalloc.h>
#include <linux/vmalloc.h>
#include <linux/device.h>
#include <linux/module.h>
@@ -215,6 +216,8 @@ struct nfit_test {

static struct workqueue_struct *nfit_wq;

+static struct gen_pool *nfit_pool;
+
static struct nfit_test *to_nfit_test(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -1132,6 +1135,9 @@ static void release_nfit_res(void *data)
list_del(&nfit_res->list);
spin_unlock(&nfit_test_lock);

+ if (resource_size(&nfit_res->res) >= DIMM_SIZE)
+ gen_pool_free(nfit_pool, nfit_res->res.start,
+ resource_size(&nfit_res->res));
vfree(nfit_res->buf);
kfree(nfit_res);
}
@@ -1144,7 +1150,7 @@ static void *__test_alloc(struct nfit_test *t, size_t size, dma_addr_t *dma,
GFP_KERNEL);
int rc;

- if (!buf || !nfit_res)
+ if (!buf || !nfit_res || !*dma)
goto err;
rc = devm_add_action(dev, release_nfit_res, nfit_res);
if (rc)
@@ -1164,6 +1170,8 @@ static void *__test_alloc(struct nfit_test *t, size_t size, dma_addr_t *dma,

return nfit_res->buf;
err:
+ if (*dma && size >= DIMM_SIZE)
+ gen_pool_free(nfit_pool, *dma, size);
if (buf)
vfree(buf);
kfree(nfit_res);
@@ -1172,9 +1180,16 @@ static void *__test_alloc(struct nfit_test *t, size_t size, dma_addr_t *dma,

static void *test_alloc(struct nfit_test *t, size_t size, dma_addr_t *dma)
{
+ struct genpool_data_align data = {
+ .align = SZ_128M,
+ };
void *buf = vmalloc(size);

- *dma = (unsigned long) buf;
+ if (size >= DIMM_SIZE)
+ *dma = gen_pool_alloc_algo(nfit_pool, size,
+ gen_pool_first_fit_align, &data);
+ else
+ *dma = (unsigned long) buf;
return __test_alloc(t, size, dma, buf);
}

@@ -2839,6 +2854,17 @@ static __init int nfit_test_init(void)
goto err_register;
}

+ nfit_pool = gen_pool_create(ilog2(SZ_4M), NUMA_NO_NODE);
+ if (!nfit_pool) {
+ rc = -ENOMEM;
+ goto err_register;
+ }
+
+ if (gen_pool_add(nfit_pool, SZ_4G, SZ_4G, NUMA_NO_NODE)) {
+ rc = -ENOMEM;
+ goto err_register;
+ }
+
for (i = 0; i < NUM_NFITS; i++) {
struct nfit_test *nfit_test;
struct platform_device *pdev;
@@ -2894,6 +2920,9 @@ static __init int nfit_test_init(void)
return 0;

err_register:
+ if (nfit_pool)
+ gen_pool_destroy(nfit_pool);
+
destroy_workqueue(nfit_wq);
for (i = 0; i < NUM_NFITS; i++)
if (instances[i])
@@ -2917,6 +2946,8 @@ static __exit void nfit_test_exit(void)
platform_driver_unregister(&nfit_test_driver);
nfit_test_teardown();

+ gen_pool_destroy(nfit_pool);
+
for (i = 0; i < NUM_NFITS; i++)
put_device(&instances[i]->pdev.dev);
class_destroy(nfit_test_dimm);