fs/ocfs2/acl.c

Source file repositories/reference/linux-study-clean/fs/ocfs2/acl.c

File Facts

System
Linux kernel
Corpus path
fs/ocfs2/acl.c
Extension
.c
Size
9500 bytes
Lines
412
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

switch(acl->a_entries[n].e_tag) {
		case ACL_USER:
			acl->a_entries[n].e_uid =
				make_kuid(&init_user_ns,
					  le32_to_cpu(entry->e_id));
			break;
		case ACL_GROUP:
			acl->a_entries[n].e_gid =
				make_kgid(&init_user_ns,
					  le32_to_cpu(entry->e_id));
			break;
		default:
			break;
		}
		value += sizeof(struct posix_acl_entry);

	}
	return acl;
}

/*
 * Convert acl struct to xattr value.
 */
static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size)
{
	struct ocfs2_acl_entry *entry = NULL;
	char *ocfs2_acl;
	size_t n;

	*size = acl->a_count * sizeof(struct posix_acl_entry);

	ocfs2_acl = kmalloc(*size, GFP_NOFS);
	if (!ocfs2_acl)
		return ERR_PTR(-ENOMEM);

	entry = (struct ocfs2_acl_entry *)ocfs2_acl;
	for (n = 0; n < acl->a_count; n++, entry++) {
		entry->e_tag  = cpu_to_le16(acl->a_entries[n].e_tag);
		entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
		switch(acl->a_entries[n].e_tag) {
		case ACL_USER:
			entry->e_id = cpu_to_le32(
				from_kuid(&init_user_ns,
					  acl->a_entries[n].e_uid));
			break;
		case ACL_GROUP:
			entry->e_id = cpu_to_le32(
				from_kgid(&init_user_ns,
					  acl->a_entries[n].e_gid));
			break;
		default:
			entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
			break;
		}
	}
	return ocfs2_acl;
}

static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode,
					      int type,
					      struct buffer_head *di_bh)
{
	int name_index;
	char *value = NULL;
	struct posix_acl *acl;
	int retval;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0);
	if (retval > 0) {
		value = kmalloc(retval, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
						"", value, retval);
	}

	if (retval > 0)
		acl = ocfs2_acl_from_xattr(value, retval);
	else if (retval == -ENODATA || retval == 0)

Annotation

Implementation Notes