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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /fs/btrfs/lru_cache.h
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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