cache.o \
daemon.o \
main.o \
+ namei.o \
security.o
cachefiles-$(CONFIG_CACHEFILES_ERROR_INJECTION) += error_inject.o
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* CacheFiles path walking and related routines
+ *
+ * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/fs.h>
+#include "internal.h"
+
+/*
+ * Mark the backing file as being a cache file if it's not already in use. The
+ * mark tells the culling request command that it's not allowed to cull the
+ * file or directory. The caller must hold the inode lock.
+ */
+static bool __cachefiles_mark_inode_in_use(struct cachefiles_object *object,
+ struct dentry *dentry)
+{
+ struct inode *inode = d_backing_inode(dentry);
+ bool can_use = false;
+
+ if (!(inode->i_flags & S_KERNEL_FILE)) {
+ inode->i_flags |= S_KERNEL_FILE;
+ trace_cachefiles_mark_active(object, inode);
+ can_use = true;
+ } else {
+ pr_notice("cachefiles: Inode already in use: %pd\n", dentry);
+ }
+
+ return can_use;
+}
+
+/*
+ * Unmark a backing inode. The caller must hold the inode lock.
+ */
+static void __cachefiles_unmark_inode_in_use(struct cachefiles_object *object,
+ struct dentry *dentry)
+{
+ struct inode *inode = d_backing_inode(dentry);
+
+ inode->i_flags &= ~S_KERNEL_FILE;
+ trace_cachefiles_mark_inactive(object, inode);
+}
inode_lock(dentry->d_inode);
error = -EBUSY;
- if (is_local_mountpoint(dentry))
+ if (is_local_mountpoint(dentry) ||
+ (dentry->d_inode->i_flags & S_KERNEL_FILE))
goto out;
error = security_inode_rmdir(dir, dentry);
#define S_ENCRYPTED (1 << 14) /* Encrypted file (using fs/crypto/) */
#define S_CASEFOLD (1 << 15) /* Casefolded file */
#define S_VERITY (1 << 16) /* Verity file (using fs/verity/) */
+#define S_KERNEL_FILE (1 << 17) /* File is in use by the kernel (eg. fs/cachefiles) */
/*
* Note that nosuid etc flags are inode-specific: setting some file-system
#define E_(a, b) { a, b }
+TRACE_EVENT(cachefiles_mark_active,
+ TP_PROTO(struct cachefiles_object *obj,
+ struct inode *inode),
+
+ TP_ARGS(obj, inode),
+
+ /* Note that obj may be NULL */
+ TP_STRUCT__entry(
+ __field(unsigned int, obj )
+ __field(ino_t, inode )
+ ),
+
+ TP_fast_assign(
+ __entry->obj = obj ? obj->debug_id : 0;
+ __entry->inode = inode->i_ino;
+ ),
+
+ TP_printk("o=%08x i=%lx",
+ __entry->obj, __entry->inode)
+ );
+
+TRACE_EVENT(cachefiles_mark_inactive,
+ TP_PROTO(struct cachefiles_object *obj,
+ struct inode *inode),
+
+ TP_ARGS(obj, inode),
+
+ /* Note that obj may be NULL */
+ TP_STRUCT__entry(
+ __field(unsigned int, obj )
+ __field(ino_t, inode )
+ ),
+
+ TP_fast_assign(
+ __entry->obj = obj ? obj->debug_id : 0;
+ __entry->inode = inode->i_ino;
+ ),
+
+ TP_printk("o=%08x i=%lx",
+ __entry->obj, __entry->inode)
+ );
+
TRACE_EVENT(cachefiles_vfs_error,
TP_PROTO(struct cachefiles_object *obj, struct inode *backer,
int error, enum cachefiles_error_trace where),