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authorRosen Penev <rosenp@gmail.com>2026-09-27 13:35:01 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-10-01 11:04:53 +0200
commit8167c1f071426706c233e93ecfd13aba7d5c06c8 (patch)
tree2c0cd5f5e1cc35eadee98d49fe034f96a88856ce /lib/cache_maint.c
downloadlinux-stable-8167c1f071426706c233e93ecfd13aba7d5c06c8.tar.gz
linux-stable-8167c1f071426706c233e93ecfd13aba7d5c06c8.zip
tty: serial: mpc52xx_uart: move static declarations up.grafted
Avoid a compilation error so that they're not used before being declared. Fixes: 4d105880666a ("tty: serial: mpc52xx_uart: add bounds check for psc_num array index") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202609260356.tJWbd1WU-lkp@intel.com/ Signed-off-by: Rosen Penev <rosenp@gmail.com> Link: https://patch.msgid.link/20260927203501.14105-1-rosenp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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");