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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /fs/btrfs/lru_cache.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'fs/btrfs/lru_cache.c')
-rw-r--r--fs/btrfs/lru_cache.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/fs/btrfs/lru_cache.c b/fs/btrfs/lru_cache.c
new file mode 100644
index 000000000..f5a053b90
--- /dev/null
+++ b/fs/btrfs/lru_cache.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/mm.h>
+#include "lru_cache.h"
+#include "messages.h"
+
+/*
+ * Initialize a cache object.
+ *
+ * @cache: The cache.
+ * @max_size: Maximum size (number of entries) for the cache.
+ * Use 0 for unlimited size, it's the user's responsibility to
+ * trim the cache in that case.
+ */
+void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size)
+{
+ INIT_LIST_HEAD(&cache->lru_list);
+ mt_init(&cache->entries);
+ cache->size = 0;
+ cache->max_size = max_size;
+}
+
+static struct btrfs_lru_cache_entry *match_entry(struct list_head *head, u64 key,
+ u64 gen)
+{
+ struct btrfs_lru_cache_entry *entry;
+
+ list_for_each_entry(entry, head, list) {
+ if (entry->key == key && entry->gen == gen)
+ return entry;
+ }
+
+ return NULL;
+}
+
+/*
+ * Lookup for an entry in the cache.
+ *
+ * @cache: The cache.
+ * @key: The key of the entry we are looking for.
+ * @gen: Generation associated to the key.
+ *
+ * Returns the entry associated with the key or NULL if none found.
+ */
+struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache,
+ u64 key, u64 gen)
+{
+ struct list_head *head;
+ struct btrfs_lru_cache_entry *entry;
+
+ head = mtree_load(&cache->entries, key);
+ if (!head)
+ return NULL;
+
+ entry = match_entry(head, key, gen);
+ if (entry)
+ list_move_tail(&entry->lru_list, &cache->lru_list);
+
+ return entry;
+}
+
+/*
+ * Remove an entry from the cache.
+ *
+ * @cache: The cache to remove from.
+ * @entry: The entry to remove from the cache.
+ *
+ * Note: this also frees the memory used by the entry.
+ */
+void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *entry)
+{
+ struct list_head *prev = entry->list.prev;
+
+ ASSERT(cache->size > 0);
+ ASSERT(!mtree_empty(&cache->entries));
+
+ list_del(&entry->list);
+ list_del(&entry->lru_list);
+
+ if (list_empty(prev)) {
+ struct list_head *head;
+
+ /*
+ * If previous element in the list entry->list is now empty, it
+ * means it's a head entry not pointing to any cached entries,
+ * so remove it from the maple tree and free it.
+ */
+ head = mtree_erase(&cache->entries, entry->key);
+ ASSERT(head == prev);
+ kfree(head);
+ }
+
+ kfree(entry);
+ cache->size--;
+}
+
+/*
+ * Store an entry in the cache.
+ *
+ * @cache: The cache.
+ * @entry: The entry to store.
+ *
+ * Returns 0 on success and < 0 on error.
+ */
+int btrfs_lru_cache_store(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *new_entry,
+ gfp_t gfp)
+{
+ const u64 key = new_entry->key;
+ struct list_head *head;
+ int ret;
+
+ head = kmalloc_obj(*head, gfp);
+ if (!head)
+ return -ENOMEM;
+
+ ret = mtree_insert(&cache->entries, key, head, gfp);
+ if (ret == 0) {
+ INIT_LIST_HEAD(head);
+ list_add_tail(&new_entry->list, head);
+ } else if (ret == -EEXIST) {
+ kfree(head);
+ head = mtree_load(&cache->entries, key);
+ ASSERT(head != NULL);
+ if (match_entry(head, key, new_entry->gen) != NULL)
+ return -EEXIST;
+ list_add_tail(&new_entry->list, head);
+ } else if (ret < 0) {
+ kfree(head);
+ return ret;
+ }
+
+ if (cache->max_size > 0 && cache->size == cache->max_size) {
+ struct btrfs_lru_cache_entry *lru_entry;
+
+ lru_entry = list_first_entry(&cache->lru_list,
+ struct btrfs_lru_cache_entry,
+ lru_list);
+ btrfs_lru_cache_remove(cache, lru_entry);
+ }
+
+ list_add_tail(&new_entry->lru_list, &cache->lru_list);
+ cache->size++;
+
+ return 0;
+}
+
+/*
+ * Empty a cache.
+ *
+ * @cache: The cache to empty.
+ *
+ * Removes all entries from the cache.
+ */
+void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache)
+{
+ struct btrfs_lru_cache_entry *entry;
+ struct btrfs_lru_cache_entry *tmp;
+
+ list_for_each_entry_safe(entry, tmp, &cache->lru_list, lru_list)
+ btrfs_lru_cache_remove(cache, entry);
+
+ ASSERT(cache->size == 0);
+ ASSERT(mtree_empty(&cache->entries));
+}