Commit 8c099490 authored by Haren Myneni's avatar Haren Myneni Committed by Michael Ellerman
Browse files

crypto/nx: Add sysfs interface to export NX capabilities 



Export NX-GZIP capabilities to usrespace in sysfs
/sys/devices/vio/ibm,compression-v1/nx_gzip_caps directory.
These are queried by userspace accelerator libraries to set
minimum length heuristics and maximum limits on request sizes.

NX-GZIP capabilities:
min_compress_len  /*Recommended minimum compress length in bytes*/
min_decompress_len /*Recommended minimum decompress length in bytes*/
req_max_processed_len /* Maximum number of bytes processed in one
			request */

NX will return RMA_Reject if the request buffer size is greater
than req_max_processed_len.

Signed-off-by: default avatarHaren Myneni <haren@linux.ibm.com>
Acked-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/510da86abbd904878d5f13d74aba72603c37d783.camel@linux.ibm.com
parent b4ba2211

drivers/crypto/nx/nx-common-pseries.c

+43 −0
Original line number Diff line number Diff line
@@ -967,6 +967,36 @@ static struct attribute_group nx842_attribute_group = { 
	.attrs = nx842_sysfs_entries,

};



#define	nxcop_caps_read(_name)						\

static ssize_t nxcop_##_name##_show(struct device *dev,			\

			struct device_attribute *attr, char *buf)	\

{									\

	return sprintf(buf, "%lld\n", nx_cop_caps._name);		\

}



#define NXCT_ATTR_RO(_name)						\

	nxcop_caps_read(_name);						\

	static struct device_attribute dev_attr_##_name = __ATTR(_name,	\

						0444,			\

						nxcop_##_name##_show,	\

						NULL);



NXCT_ATTR_RO(req_max_processed_len);

NXCT_ATTR_RO(min_compress_len);

NXCT_ATTR_RO(min_decompress_len);



static struct attribute *nxcop_caps_sysfs_entries[] = {

	&dev_attr_req_max_processed_len.attr,

	&dev_attr_min_compress_len.attr,

	&dev_attr_min_decompress_len.attr,

	NULL,

};



static struct attribute_group nxcop_caps_attr_group = {

	.name	=	"nx_gzip_caps",

	.attrs	=	nxcop_caps_sysfs_entries,

};



static struct nx842_driver nx842_pseries_driver = {

	.name =		KBUILD_MODNAME,

	.owner =	THIS_MODULE,
@@ -1056,6 +1086,16 @@ static int nx842_probe(struct vio_dev *viodev, 
		goto error;

	}



	if (caps_feat) {

		if (sysfs_create_group(&viodev->dev.kobj,

					&nxcop_caps_attr_group)) {

			dev_err(&viodev->dev,

				"Could not create sysfs NX capability entries\n");

			ret = -1;

			goto error;

		}

	}



	return 0;



error_unlock:
@@ -1075,6 +1115,9 @@ static void nx842_remove(struct vio_dev *viodev) 
	pr_info("Removing IBM Power 842 compression device\n");

	sysfs_remove_group(&viodev->dev.kobj, &nx842_attribute_group);



	if (caps_feat)

		sysfs_remove_group(&viodev->dev.kobj, &nxcop_caps_attr_group);



	crypto_unregister_alg(&nx842_pseries_alg);



	spin_lock_irqsave(&devdata_mutex, flags);