From e31fc778998b4d02ffec68e61869aaeccfd99be8 Mon Sep 17 00:00:00 2001

From: Dan Williams <dan.j.williams@intel.com>

Date: Sun, 23 Jan 2022 16:54:17 -0800

Subject: [PATCH 114/217] util: Implement common bind/unbind helpers

Refactor ndctl_{bind,unbind}() into util_{bind,unbind}() for libcxl to

reuse.

daxctl can not join the party for now as it needs to play games with

'new_id'.

Link: https://lore.kernel.org/r/164298565707.3021641.7763459936156744907.stgit@dwillia2-desk3.amr.corp.intel.com

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

---

 ndctl/lib/libndctl.c | 103 +++++--------------------------------------

 util/sysfs.c         |  76 +++++++++++++++++++++++++++++++

 util/sysfs.h         |   8 ++++

 3 files changed, 96 insertions(+), 91 deletions(-)

diff --git a/ndctl/lib/libndctl.c b/ndctl/lib/libndctl.c

index 1374ad9..98d184b 100644

--- a/ndctl/lib/libndctl.c

+++ b/ndctl/lib/libndctl.c

@@ -1665,10 +1665,6 @@ static enum ndctl_fwa_result fwa_result_to_result(const char *result)

 	return NDCTL_FWA_RESULT_INVALID;

 }

-static int ndctl_bind(struct ndctl_ctx *ctx, struct kmod_module *module,

-		const char *devname);

-static int ndctl_unbind(struct ndctl_ctx *ctx, const char *devpath);

-

 static int populate_dimm_attributes(struct ndctl_dimm *dimm,

 				    const char *dimm_base,

 				    const char *bus_prefix)

@@ -2305,7 +2301,7 @@ NDCTL_EXPORT int ndctl_dimm_disable(struct ndctl_dimm *dimm)

 	if (!ndctl_dimm_is_enabled(dimm))

 		return 0;

-	ndctl_unbind(ctx, dimm->dimm_path);

+	util_unbind(dimm->dimm_path, ctx);

 	if (ndctl_dimm_is_enabled(dimm)) {

 		err(ctx, "%s: failed to disable\n", devname);

@@ -2324,7 +2320,7 @@ NDCTL_EXPORT int ndctl_dimm_enable(struct ndctl_dimm *dimm)

 	if (ndctl_dimm_is_enabled(dimm))

 		return 0;

-	ndctl_bind(ctx, dimm->module, devname);

+	util_bind(devname, dimm->module, "nd", ctx);

 	if (!ndctl_dimm_is_enabled(dimm)) {

 		err(ctx, "%s: failed to enable\n", devname);

@@ -3573,7 +3569,7 @@ NDCTL_EXPORT int ndctl_region_enable(struct ndctl_region *region)

 	if (ndctl_region_is_enabled(region))

 		return 0;

-	ndctl_bind(ctx, region->module, devname);

+	util_bind(devname, region->module, "nd", ctx);

 	if (!ndctl_region_is_enabled(region)) {

 		err(ctx, "%s: failed to enable\n", devname);

@@ -3610,7 +3606,7 @@ static int ndctl_region_disable(struct ndctl_region *region, int cleanup)

 	if (!ndctl_region_is_enabled(region))

 		return 0;

-	ndctl_unbind(ctx, region->region_path);

+	util_unbind(region->region_path, ctx);

 	if (ndctl_region_is_enabled(region)) {

 		err(ctx, "%s: failed to disable\n", devname);

@@ -4373,81 +4369,6 @@ NDCTL_EXPORT struct badblock *ndctl_namespace_get_first_badblock(

 	return badblocks_iter_first(&ndns->bb_iter, ctx, path);

 }

-static int ndctl_bind(struct ndctl_ctx *ctx, struct kmod_module *module,

-		const char *devname)

-{

-	DIR *dir;

-	int rc = 0;

-	char path[200];

-	struct dirent *de;

-	const int len = sizeof(path);

-

-	if (!devname) {

-		err(ctx, "missing devname\n");

-		return -EINVAL;

-	}

-

-	if (module) {

-		rc = kmod_module_probe_insert_module(module,

-				KMOD_PROBE_APPLY_BLACKLIST, NULL, NULL, NULL,

-				NULL);

-		if (rc < 0) {

-			err(ctx, "%s: insert failure: %d\n", __func__, rc);

-			return rc;

-		}

-	}

-

-	if (snprintf(path, len, "/sys/bus/nd/drivers") >= len) {

-		err(ctx, "%s: buffer too small!\n", devname);

-		return -ENXIO;

-	}

-

-	dir = opendir(path);

-	if (!dir) {

-		err(ctx, "%s: opendir(\"%s\") failed\n", devname, path);

-		return -ENXIO;

-	}

-

-	while ((de = readdir(dir)) != NULL) {

-		char *drv_path;

-

-		if (de->d_ino == 0)

-			continue;

-		if (de->d_name[0] == '.')

-			continue;

-		if (asprintf(&drv_path, "%s/%s/bind", path, de->d_name) < 0) {

-			err(ctx, "%s: path allocation failure\n", devname);

-			continue;

-		}

-

-		rc = sysfs_write_attr_quiet(ctx, drv_path, devname);

-		free(drv_path);

-		if (rc == 0)

-			break;

-	}

-	closedir(dir);

-

-	if (rc) {

-		dbg(ctx, "%s: bind failed\n", devname);

-		return -ENXIO;

-	}

-	return 0;

-}

-

-static int ndctl_unbind(struct ndctl_ctx *ctx, const char *devpath)

-{

-	const char *devname = devpath_to_devname(devpath);

-	char path[200];

-	const int len = sizeof(path);

-

-	if (snprintf(path, len, "%s/driver/unbind", devpath) >= len) {

-		err(ctx, "%s: buffer too small!\n", devname);

-		return -ENXIO;

-	}

-

-	return sysfs_write_attr(ctx, path, devname);

-}

-

 static void *add_btt(void *parent, int id, const char *btt_base);

 static void *add_pfn(void *parent, int id, const char *pfn_base);

 static void *add_dax(void *parent, int id, const char *dax_base);

@@ -4533,7 +4454,7 @@ NDCTL_EXPORT int ndctl_namespace_enable(struct ndctl_namespace *ndns)

 	if (ndctl_namespace_is_enabled(ndns))

 		return 0;

-	rc = ndctl_bind(ctx, ndns->module, devname);

+	rc = util_bind(devname, ndns->module, "nd", ctx);

 	/*

 	 * Rescan now as successfully enabling a namespace device leads

@@ -4581,7 +4502,7 @@ NDCTL_EXPORT int ndctl_namespace_disable(struct ndctl_namespace *ndns)

 	if (!ndctl_namespace_is_enabled(ndns))

 		return 0;

-	ndctl_unbind(ctx, ndns->ndns_path);

+	util_unbind(ndns->ndns_path, ctx);

 	if (ndctl_namespace_is_enabled(ndns)) {

 		err(ctx, "%s: failed to disable\n", devname);

@@ -5420,7 +5341,7 @@ NDCTL_EXPORT int ndctl_btt_enable(struct ndctl_btt *btt)

 	if (ndctl_btt_is_enabled(btt))

 		return 0;

-	ndctl_bind(ctx, btt->module, devname);

+	util_bind(devname, btt->module, "nd", ctx);

 	if (!ndctl_btt_is_enabled(btt)) {

 		err(ctx, "%s: failed to enable\n", devname);

@@ -5457,7 +5378,7 @@ NDCTL_EXPORT int ndctl_btt_delete(struct ndctl_btt *btt)

 		return 0;

 	}

-	ndctl_unbind(ctx, btt->btt_path);

+	util_unbind(btt->btt_path, ctx);

 	rc = ndctl_btt_set_namespace(btt, NULL);

 	if (rc) {

@@ -5908,7 +5829,7 @@ NDCTL_EXPORT int ndctl_pfn_enable(struct ndctl_pfn *pfn)

 	if (ndctl_pfn_is_enabled(pfn))

 		return 0;

-	ndctl_bind(ctx, pfn->module, devname);

+	util_bind(devname, pfn->module, "nd", ctx);

 	if (!ndctl_pfn_is_enabled(pfn)) {

 		err(ctx, "%s: failed to enable\n", devname);

@@ -5945,7 +5866,7 @@ NDCTL_EXPORT int ndctl_pfn_delete(struct ndctl_pfn *pfn)

 		return 0;

 	}

-	ndctl_unbind(ctx, pfn->pfn_path);

+	util_unbind(pfn->pfn_path, ctx);

 	rc = ndctl_pfn_set_namespace(pfn, NULL);

 	if (rc) {

@@ -6101,7 +6022,7 @@ NDCTL_EXPORT int ndctl_dax_enable(struct ndctl_dax *dax)

 	if (ndctl_dax_is_enabled(dax))

 		return 0;

-	ndctl_bind(ctx, pfn->module, devname);

+	util_bind(devname, pfn->module, "nd", ctx);

 	if (!ndctl_dax_is_enabled(dax)) {

 		err(ctx, "%s: failed to enable\n", devname);

@@ -6132,7 +6053,7 @@ NDCTL_EXPORT int ndctl_dax_delete(struct ndctl_dax *dax)

 		return 0;

 	}

-	ndctl_unbind(ctx, pfn->pfn_path);

+	util_unbind(pfn->pfn_path, ctx);

 	rc = ndctl_dax_set_namespace(dax, NULL);

 	if (rc) {

diff --git a/util/sysfs.c b/util/sysfs.c

index 23330cb..968683b 100644

--- a/util/sysfs.c

+++ b/util/sysfs.c

@@ -145,3 +145,79 @@ struct kmod_module *__util_modalias_to_module(struct kmod_ctx *kmod_ctx,

 	return mod;

 }

+

+int __util_bind(const char *devname, struct kmod_module *module,

+		const char *bus, struct log_ctx *ctx)

+{

+	DIR *dir;

+	int rc = 0;

+	char path[200];

+	struct dirent *de;

+	const int len = sizeof(path);

+

+	if (!devname) {

+		log_err(ctx, "missing devname\n");

+		return -EINVAL;

+	}

+

+	if (module) {

+		rc = kmod_module_probe_insert_module(module,

+						     KMOD_PROBE_APPLY_BLACKLIST,

+						     NULL, NULL, NULL, NULL);

+		if (rc < 0) {

+			log_err(ctx, "%s: insert failure: %d\n", __func__, rc);

+			return rc;

+		}

+	}

+

+	if (snprintf(path, len, "/sys/bus/%s/drivers", bus) >= len) {

+		log_err(ctx, "%s: buffer too small!\n", devname);

+		return -ENXIO;

+	}

+

+	dir = opendir(path);

+	if (!dir) {

+		log_err(ctx, "%s: opendir(\"%s\") failed\n", devname, path);

+		return -ENXIO;

+	}

+

+	while ((de = readdir(dir)) != NULL) {

+		char *drv_path;

+

+		if (de->d_ino == 0)

+			continue;

+		if (de->d_name[0] == '.')

+			continue;

+

+		if (asprintf(&drv_path, "%s/%s/bind", path, de->d_name) < 0) {

+			log_err(ctx, "%s: path allocation failure\n", devname);

+			continue;

+		}

+

+		rc = __sysfs_write_attr_quiet(ctx, drv_path, devname);

+		free(drv_path);

+		if (rc == 0)

+			break;

+	}

+	closedir(dir);

+

+	if (rc) {

+		log_dbg(ctx, "%s: bind failed\n", devname);

+		return -ENXIO;

+	}

+	return 0;

+}

+

+int __util_unbind(const char *devpath, struct log_ctx *ctx)

+{

+	const char *devname = devpath_to_devname(devpath);

+	char path[200];

+	const int len = sizeof(path);

+

+	if (snprintf(path, len, "%s/driver/unbind", devpath) >= len) {

+		log_err(ctx, "%s: buffer too small!\n", devname);

+		return -ENXIO;

+	}

+

+	return __sysfs_write_attr(ctx, path, devname);

+}

diff --git a/util/sysfs.h b/util/sysfs.h

index bdee4f5..4c95c70 100644

--- a/util/sysfs.h

+++ b/util/sysfs.h

@@ -35,4 +35,12 @@ struct kmod_module *__util_modalias_to_module(struct kmod_ctx *kmod_ctx,

 					      struct log_ctx *log);

 #define util_modalias_to_module(ctx, buf)                                      \

 	__util_modalias_to_module((ctx)->kmod_ctx, buf, &(ctx)->ctx)

+

+int __util_bind(const char *devname, struct kmod_module *module, const char *bus,

+	      struct log_ctx *ctx);

+#define util_bind(n, m, b, c) __util_bind(n, m, b, &(c)->ctx)

+

+int __util_unbind(const char *devpath, struct log_ctx *ctx);

+#define util_unbind(p, c) __util_unbind(p, &(c)->ctx)

+

 #endif /* __UTIL_SYSFS_H__ */

-- 

2.27.0