diff mbox series

[ndctl,v2,06/10] libdaxctl: add daxctl_region_create_dev()

Message ID 20200713160837.13774-7-joao.m.martins@oracle.com (mailing list archive)
State New, archived
Headers show
Series daxctl: Support for sub-dividing soft-reserved regions | expand

Commit Message

Joao Martins July 13, 2020, 4:08 p.m. UTC 
Add an API to create an empty seed device.

This sysfs attribute is only writeable for a dynamic
dax device such as the one exported by hmem.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 daxctl/lib/libdaxctl.c   | 26 ++++++++++++++++++++++++++
 daxctl/lib/libdaxctl.sym |  1 +
 daxctl/libdaxctl.h       |  1 +
 3 files changed, 28 insertions(+)
diff mbox series

Patch

diff --git a/daxctl/lib/libdaxctl.c b/daxctl/lib/libdaxctl.c
index 00d5f7fe61ad..d17ff7a02bad 100644
--- a/daxctl/lib/libdaxctl.c
+++ b/daxctl/lib/libdaxctl.c
@@ -583,6 +583,32 @@  DAXCTL_EXPORT unsigned long long daxctl_region_get_available_size(
 	return 0;
 }
 
+DAXCTL_EXPORT int daxctl_region_create_dev(struct daxctl_region *region)
+{
+	struct daxctl_ctx *ctx = daxctl_region_get_ctx(region);
+	char *path = region->region_buf;
+	int rc, len = region->buf_len;
+	char *num_devices;
+
+	if (snprintf(path, len, "%s/%s/create", region->region_path, attrs) >= len) {
+		err(ctx, "%s: buffer too small!\n",
+				daxctl_region_get_devname(region));
+		return -EFAULT;
+	}
+
+	if (asprintf(&num_devices, "%d", 1) < 0) {
+		err(ctx, "%s: buffer too small!\n",
+				daxctl_region_get_devname(region));
+		return -EFAULT;
+	}
+
+	rc = sysfs_write_attr(ctx, path, num_devices);
+	if (rc)
+		return rc;
+
+	return 0;
+}
+
 DAXCTL_EXPORT struct daxctl_dev *daxctl_region_get_dev_seed(
 		struct daxctl_region *region)
 {
diff --git a/daxctl/lib/libdaxctl.sym b/daxctl/lib/libdaxctl.sym
index d8b4137c76b7..26987ba021ab 100644
--- a/daxctl/lib/libdaxctl.sym
+++ b/daxctl/lib/libdaxctl.sym
@@ -79,4 +79,5 @@  global:
 LIBDAXCTL_8 {
 global:
 	daxctl_dev_set_size;
+	daxctl_region_create_dev;
 } LIBDAXCTL_7;
diff --git a/daxctl/libdaxctl.h b/daxctl/libdaxctl.h
index e3d482743cc6..a579ddd1d43c 100644
--- a/daxctl/libdaxctl.h
+++ b/daxctl/libdaxctl.h
@@ -56,6 +56,7 @@  unsigned long daxctl_region_get_align(struct daxctl_region *region);
 const char *daxctl_region_get_devname(struct daxctl_region *region);
 const char *daxctl_region_get_path(struct daxctl_region *region);
 
+int daxctl_region_create_dev(struct daxctl_region *region);
 struct daxctl_dev *daxctl_region_get_dev_seed(struct daxctl_region *region);
 
 struct daxctl_dev;