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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /lib/cache_maint.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'lib/cache_maint.c')
-rw-r--r--lib/cache_maint.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/lib/cache_maint.c b/lib/cache_maint.c
new file mode 100644
index 000000000..9256a9ffc
--- /dev/null
+++ b/lib/cache_maint.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic support for Memory System Cache Maintenance operations.
+ *
+ * Coherency maintenance drivers register with this simple framework that will
+ * iterate over each registered instance to first kick off invalidation and
+ * then to wait until it is complete.
+ *
+ * If no implementations are registered yet cpu_cache_has_invalidate_memregion()
+ * will return false. If this runs concurrently with unregistration then a
+ * race exists but this is no worse than the case where the operations instance
+ * responsible for a given memory region has not yet registered.
+ */
+#include <linux/cache_coherency.h>
+#include <linux/cleanup.h>
+#include <linux/container_of.h>
+#include <linux/export.h>
+#include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/memregion.h>
+#include <linux/module.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+
+static LIST_HEAD(cache_ops_instance_list);
+static DECLARE_RWSEM(cache_ops_instance_list_lock);
+
+static void __cache_coherency_ops_instance_free(struct kref *kref)
+{
+ struct cache_coherency_ops_inst *cci =
+ container_of(kref, struct cache_coherency_ops_inst, kref);
+ kfree(cci);
+}
+
+void cache_coherency_ops_instance_put(struct cache_coherency_ops_inst *cci)
+{
+ kref_put(&cci->kref, __cache_coherency_ops_instance_free);
+}
+EXPORT_SYMBOL_GPL(cache_coherency_ops_instance_put);
+
+static int cache_inval_one(struct cache_coherency_ops_inst *cci, void *data)
+{
+ if (!cci->ops)
+ return -EINVAL;
+
+ return cci->ops->wbinv(cci, data);
+}
+
+static int cache_inval_done_one(struct cache_coherency_ops_inst *cci)
+{
+ if (!cci->ops)
+ return -EINVAL;
+
+ if (!cci->ops->done)
+ return 0;
+
+ return cci->ops->done(cci);
+}
+
+static int cache_invalidate_memregion(phys_addr_t addr, size_t size)
+{
+ int ret;
+ struct cache_coherency_ops_inst *cci;
+ struct cc_inval_params params = {
+ .addr = addr,
+ .size = size,
+ };
+
+ guard(rwsem_read)(&cache_ops_instance_list_lock);
+ list_for_each_entry(cci, &cache_ops_instance_list, node) {
+ ret = cache_inval_one(cci, &params);
+ if (ret)
+ return ret;
+ }
+ list_for_each_entry(cci, &cache_ops_instance_list, node) {
+ ret = cache_inval_done_one(cci);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+struct cache_coherency_ops_inst *
+_cache_coherency_ops_instance_alloc(const struct cache_coherency_ops *ops,
+ size_t size)
+{
+ struct cache_coherency_ops_inst *cci;
+
+ if (!ops || !ops->wbinv)
+ return NULL;
+
+ cci = kzalloc(size, GFP_KERNEL);
+ if (!cci)
+ return NULL;
+
+ cci->ops = ops;
+ INIT_LIST_HEAD(&cci->node);
+ kref_init(&cci->kref);
+
+ return cci;
+}
+EXPORT_SYMBOL_NS_GPL(_cache_coherency_ops_instance_alloc, "CACHE_COHERENCY");
+
+int cache_coherency_ops_instance_register(struct cache_coherency_ops_inst *cci)
+{
+ guard(rwsem_write)(&cache_ops_instance_list_lock);
+ list_add(&cci->node, &cache_ops_instance_list);
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cache_coherency_ops_instance_register, "CACHE_COHERENCY");
+
+void cache_coherency_ops_instance_unregister(struct cache_coherency_ops_inst *cci)
+{
+ guard(rwsem_write)(&cache_ops_instance_list_lock);
+ list_del(&cci->node);
+}
+EXPORT_SYMBOL_NS_GPL(cache_coherency_ops_instance_unregister, "CACHE_COHERENCY");
+
+int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len)
+{
+ return cache_invalidate_memregion(start, len);
+}
+EXPORT_SYMBOL_NS_GPL(cpu_cache_invalidate_memregion, "DEVMEM");
+
+/*
+ * Used for optimization / debug purposes only as removal can race
+ *
+ * Machines that do not support invalidation, e.g. VMs, will not have any
+ * operations instance to register and so this will always return false.
+ */
+bool cpu_cache_has_invalidate_memregion(void)
+{
+ guard(rwsem_read)(&cache_ops_instance_list_lock);
+ return !list_empty(&cache_ops_instance_list);
+}
+EXPORT_SYMBOL_NS_GPL(cpu_cache_has_invalidate_memregion, "DEVMEM");