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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
commita9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch)
treecc62d74e0eb4905246978674461e78e2f9df2afd /include/net/dst_cache.h
downloadlinux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz
linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'include/net/dst_cache.h')
-rw-r--r--include/net/dst_cache.h109
1 files changed, 109 insertions, 0 deletions
diff --git a/include/net/dst_cache.h b/include/net/dst_cache.h
new file mode 100644
index 000000000..196169959
--- /dev/null
+++ b/include/net/dst_cache.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_DST_CACHE_H
+#define _NET_DST_CACHE_H
+
+#include <linux/jiffies.h>
+#include <net/dst.h>
+#if IS_ENABLED(CONFIG_IPV6)
+#include <net/ip6_fib.h>
+#endif
+
+struct dst_cache {
+ struct dst_cache_pcpu __percpu *cache;
+ unsigned long reset_ts;
+};
+
+/**
+ * dst_cache_get - perform cache lookup
+ * @dst_cache: the cache
+ *
+ * The caller should use dst_cache_get_ip4() if it need to retrieve the
+ * source address to be used when xmitting to the cached dst.
+ * local BH must be disabled.
+ */
+struct dst_entry *dst_cache_get(struct dst_cache *dst_cache);
+
+/**
+ * dst_cache_get_ip4 - perform cache lookup and fetch ipv4 source address
+ * @dst_cache: the cache
+ * @saddr: return value for the retrieved source address
+ *
+ * local BH must be disabled.
+ */
+struct rtable *dst_cache_get_ip4(struct dst_cache *dst_cache, __be32 *saddr);
+
+/**
+ * dst_cache_set_ip4 - store the ipv4 dst into the cache
+ * @dst_cache: the cache
+ * @dst: the entry to be cached
+ * @saddr: the source address to be stored inside the cache
+ *
+ * local BH must be disabled.
+ */
+void dst_cache_set_ip4(struct dst_cache *dst_cache, struct dst_entry *dst,
+ __be32 saddr);
+
+#if IS_ENABLED(CONFIG_IPV6)
+
+/**
+ * dst_cache_set_ip6 - store the ipv6 dst into the cache
+ * @dst_cache: the cache
+ * @dst: the entry to be cached
+ * @saddr: the source address to be stored inside the cache
+ *
+ * local BH must be disabled.
+ */
+void dst_cache_set_ip6(struct dst_cache *dst_cache, struct dst_entry *dst,
+ const struct in6_addr *saddr);
+
+/**
+ * dst_cache_get_ip6 - perform cache lookup and fetch ipv6 source address
+ * @dst_cache: the cache
+ * @saddr: return value for the retrieved source address
+ *
+ * local BH must be disabled.
+ */
+struct dst_entry *dst_cache_get_ip6(struct dst_cache *dst_cache,
+ struct in6_addr *saddr);
+#endif
+
+/**
+ * dst_cache_reset - invalidate the cache contents
+ * @dst_cache: the cache
+ *
+ * This does not free the cached dst to avoid races and contentions.
+ * the dst will be freed on later cache lookup.
+ */
+static inline void dst_cache_reset(struct dst_cache *dst_cache)
+{
+ WRITE_ONCE(dst_cache->reset_ts, jiffies);
+}
+
+/**
+ * dst_cache_reset_now - invalidate the cache contents immediately
+ * @dst_cache: the cache
+ *
+ * The caller must be sure there are no concurrent users, as this frees
+ * all dst_cache users immediately, rather than waiting for the next
+ * per-cpu usage like dst_cache_reset does. Most callers should use the
+ * higher speed lazily-freed dst_cache_reset function instead.
+ */
+void dst_cache_reset_now(struct dst_cache *dst_cache);
+
+/**
+ * dst_cache_init - initialize the cache, allocating the required storage
+ * @dst_cache: the cache
+ * @gfp: allocation flags
+ */
+int dst_cache_init(struct dst_cache *dst_cache, gfp_t gfp);
+
+/**
+ * dst_cache_destroy - empty the cache and free the allocated storage
+ * @dst_cache: the cache
+ *
+ * No synchronization is enforced: it must be called only when the cache
+ * is unused.
+ */
+void dst_cache_destroy(struct dst_cache *dst_cache);
+
+#endif