Re: [PATCH 1/2] tools/testing/nvdimm: Align test resources to 128M

[Verma, Vishal L]

On Sat, 2018-11-24 at 10:46 -0800, Dan Williams wrote:
> 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.
> 
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
>  tools/testing/nvdimm/test/nfit.c |   36 ++++++++++++++++++++++++++++++++++--
>  1 file changed, 34 insertions(+), 2 deletions(-)
> 

This looks good to me,
Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>

> diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
> index 01ec04bf91b5..ca4e61c864d5 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 +2854,18 @@ 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, VMALLOC_START,
> +				VMALLOC_END + 1 - VMALLOC_START, 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 +2921,9 @@ 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 +2947,8 @@ 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);
>