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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/btrfs/lru_cache.h
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'fs/btrfs/lru_cache.h')
-rw-r--r--fs/btrfs/lru_cache.h71
1 files changed, 71 insertions, 0 deletions
diff --git a/fs/btrfs/lru_cache.h b/fs/btrfs/lru_cache.h
new file mode 100644
index 000000000..07f1bb1c6
--- /dev/null
+++ b/fs/btrfs/lru_cache.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_LRU_CACHE_H
+#define BTRFS_LRU_CACHE_H
+
+#include <linux/types.h>
+#include <linux/maple_tree.h>
+#include <linux/list.h>
+
+/*
+ * A cache entry. This is meant to be embedded in a structure of a user of
+ * this module. Similar to how struct list_head and struct rb_node are used.
+ *
+ * Note: it should be embedded as the first element in a struct (offset 0), and
+ * this module assumes it was allocated with kmalloc(), so it calls kfree() when
+ * it needs to free an entry.
+ */
+struct btrfs_lru_cache_entry {
+ struct list_head lru_list;
+ u64 key;
+ /*
+ * Optional generation associated to a key. Use 0 if not needed/used.
+ * Entries with the same key and different generations are stored in a
+ * linked list, so use this only for cases where there's a small number
+ * of different generations.
+ */
+ u64 gen;
+ /*
+ * The maple tree uses unsigned long type for the keys, which is 32 bits
+ * on 32 bits systems, and 64 bits on 64 bits systems. So if we want to
+ * use something like inode numbers as keys, which are always a u64, we
+ * have to deal with this in a special way - we store the key in the
+ * entry itself, as a u64, and the values inserted into the maple tree
+ * are linked lists of entries - so in case we are on a 64 bits system,
+ * that list always has a single entry, while on 32 bits systems it
+ * may have more than one, with each entry having the same value for
+ * their lower 32 bits of the u64 key.
+ */
+ struct list_head list;
+};
+
+struct btrfs_lru_cache {
+ struct list_head lru_list;
+ struct maple_tree entries;
+ /* Number of entries stored in the cache. */
+ unsigned int size;
+ /* Maximum number of entries the cache can have. */
+ unsigned int max_size;
+};
+
+#define btrfs_lru_cache_for_each_entry_safe(cache, entry, tmp) \
+ list_for_each_entry_safe_reverse((entry), (tmp), &(cache)->lru_list, lru_list)
+
+static inline struct btrfs_lru_cache_entry *btrfs_lru_cache_lru_entry(
+ struct btrfs_lru_cache *cache)
+{
+ return list_first_entry_or_null(&cache->lru_list,
+ struct btrfs_lru_cache_entry, lru_list);
+}
+
+void btrfs_lru_cache_init(struct btrfs_lru_cache *cache, unsigned int max_size);
+struct btrfs_lru_cache_entry *btrfs_lru_cache_lookup(struct btrfs_lru_cache *cache,
+ u64 key, u64 gen);
+int btrfs_lru_cache_store(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *new_entry,
+ gfp_t gfp);
+void btrfs_lru_cache_remove(struct btrfs_lru_cache *cache,
+ struct btrfs_lru_cache_entry *entry);
+void btrfs_lru_cache_clear(struct btrfs_lru_cache *cache);
+
+#endif