diff mbox series

[v4,09/10] tmpfs: Expose filesystem features via sysfs

Message ID 20240911144502.115260-10-andrealmeid@igalia.com (mailing list archive)
State New
Headers show
Series tmpfs: Add case-insensitive support for tmpfs | expand

Commit Message

André Almeida Sept. 11, 2024, 2:45 p.m. UTC 
Expose filesystem features through sysfs, so userspace can query if
tmpfs support casefold.

This follows the same setup as defined by ext4 and f2fs to expose
casefold support to userspace.

Signed-off-by: André Almeida <andrealmeid@igalia.com>
---
 mm/shmem.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

Comments

Gabriel Krisman Bertazi Sept. 12, 2024, 7:07 p.m. UTC | #1 
André Almeida <andrealmeid@igalia.com> writes:

> Expose filesystem features through sysfs, so userspace can query if
> tmpfs support casefold.
>
> This follows the same setup as defined by ext4 and f2fs to expose
> casefold support to userspace.

Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de>
diff mbox series

Patch

diff --git a/mm/shmem.c b/mm/shmem.c
index fc0e0cd46146..7e7e2461a314 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -5401,3 +5401,40 @@  struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
 	return page;
 }
 EXPORT_SYMBOL_GPL(shmem_read_mapping_page_gfp);
+
+#if defined(CONFIG_SYSFS) && defined(CONFIG_TMPFS)
+#if IS_ENABLED(CONFIG_UNICODE)
+static DEVICE_STRING_ATTR_RO(casefold, 0444, "supported");
+#endif
+
+static struct attribute *tmpfs_attributes[] = {
+#if IS_ENABLED(CONFIG_UNICODE)
+	&dev_attr_casefold.attr.attr,
+#endif
+	NULL
+};
+
+static const struct attribute_group tmpfs_attribute_group = {
+	.attrs = tmpfs_attributes,
+	.name = "features"
+};
+
+static struct kobject *tmpfs_kobj;
+
+static int __init tmpfs_sysfs_init(void)
+{
+	int ret;
+
+	tmpfs_kobj = kobject_create_and_add("tmpfs", fs_kobj);
+	if (!tmpfs_kobj)
+		return -ENOMEM;
+
+	ret = sysfs_create_group(tmpfs_kobj, &tmpfs_attribute_group);
+	if (ret)
+		kobject_put(tmpfs_kobj);
+
+	return ret;
+}
+
+fs_initcall(tmpfs_sysfs_init);
+#endif /* CONFIG_SYSFS && CONFIG_TMPFS */