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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
commit9f0346dcbea363787186c94ef94dd01aaa215afa (patch)
treeb81c168f4d0dbe4c7f4750f4598d48a6deb72094 /lib/cache_maint.c
downloadlinux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz
linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
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");