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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 /drivers/md/dm-pcache/cache.c
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 'drivers/md/dm-pcache/cache.c')
-rw-r--r--drivers/md/dm-pcache/cache.c478
1 files changed, 478 insertions, 0 deletions
diff --git a/drivers/md/dm-pcache/cache.c b/drivers/md/dm-pcache/cache.c
new file mode 100644
index 000000000..b0b3e2167
--- /dev/null
+++ b/drivers/md/dm-pcache/cache.c
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/blk_types.h>
+
+#include "cache.h"
+#include "cache_dev.h"
+#include "backing_dev.h"
+#include "dm_pcache.h"
+
+struct kmem_cache *key_cache;
+
+static inline struct pcache_cache_info *get_cache_info_addr(struct pcache_cache *cache)
+{
+ return (struct pcache_cache_info *)((char *)cache->cache_info_addr +
+ (size_t)cache->info_index * PCACHE_CACHE_INFO_SIZE);
+}
+
+static void cache_info_write(struct pcache_cache *cache)
+{
+ struct pcache_cache_info *cache_info = &cache->cache_info;
+
+ cache_info->header.seq++;
+ cache_info->header.crc = pcache_meta_crc(&cache_info->header,
+ sizeof(struct pcache_cache_info));
+
+ cache->info_index = (cache->info_index + 1) % PCACHE_META_INDEX_MAX;
+ memcpy_flushcache(get_cache_info_addr(cache), cache_info,
+ sizeof(struct pcache_cache_info));
+ pmem_wmb();
+}
+
+static void cache_info_init_default(struct pcache_cache *cache);
+static int cache_info_init(struct pcache_cache *cache, struct pcache_cache_options *opts)
+{
+ struct dm_pcache *pcache = CACHE_TO_PCACHE(cache);
+ struct pcache_cache_info *cache_info_addr;
+
+ cache_info_addr = pcache_meta_find_latest(&cache->cache_info_addr->header,
+ sizeof(struct pcache_cache_info),
+ PCACHE_CACHE_INFO_SIZE,
+ &cache->cache_info);
+ if (IS_ERR(cache_info_addr))
+ return PTR_ERR(cache_info_addr);
+
+ if (cache_info_addr) {
+ if (opts->data_crc !=
+ (cache->cache_info.flags & PCACHE_CACHE_FLAGS_DATA_CRC)) {
+ pcache_dev_err(pcache, "invalid option for data_crc: %s, expected: %s",
+ opts->data_crc ? "true" : "false",
+ cache->cache_info.flags & PCACHE_CACHE_FLAGS_DATA_CRC ? "true" : "false");
+ return -EINVAL;
+ }
+
+ cache->info_index = ((char *)cache_info_addr - (char *)cache->cache_info_addr) / PCACHE_CACHE_INFO_SIZE;
+
+ return 0;
+ }
+
+ /* init cache_info for new cache */
+ cache_info_init_default(cache);
+ cache_mode_set(cache, opts->cache_mode);
+ if (opts->data_crc)
+ cache->cache_info.flags |= PCACHE_CACHE_FLAGS_DATA_CRC;
+
+ return 0;
+}
+
+static void cache_info_set_gc_percent(struct pcache_cache_info *cache_info, u8 percent)
+{
+ cache_info->flags &= ~PCACHE_CACHE_FLAGS_GC_PERCENT_MASK;
+ cache_info->flags |= FIELD_PREP(PCACHE_CACHE_FLAGS_GC_PERCENT_MASK, percent);
+}
+
+int pcache_cache_set_gc_percent(struct pcache_cache *cache, u8 percent)
+{
+ if (percent > PCACHE_CACHE_GC_PERCENT_MAX || percent < PCACHE_CACHE_GC_PERCENT_MIN)
+ return -EINVAL;
+
+ mutex_lock(&cache->cache_info_lock);
+ cache_info_set_gc_percent(&cache->cache_info, percent);
+
+ cache_info_write(cache);
+ mutex_unlock(&cache->cache_info_lock);
+
+ return 0;
+}
+
+void cache_pos_encode(struct pcache_cache *cache,
+ struct pcache_cache_pos_onmedia *pos_onmedia_base,
+ struct pcache_cache_pos *pos, u64 seq, u32 *index)
+{
+ struct pcache_cache_pos_onmedia pos_onmedia;
+ struct pcache_cache_pos_onmedia *pos_onmedia_addr = pos_onmedia_base + *index;
+
+ pos_onmedia.cache_seg_id = pos->cache_seg->cache_seg_id;
+ pos_onmedia.seg_off = pos->seg_off;
+ pos_onmedia.header.seq = seq;
+ pos_onmedia.header.crc = cache_pos_onmedia_crc(&pos_onmedia);
+
+ *index = (*index + 1) % PCACHE_META_INDEX_MAX;
+
+ memcpy_flushcache(pos_onmedia_addr, &pos_onmedia, sizeof(struct pcache_cache_pos_onmedia));
+ pmem_wmb();
+}
+
+int cache_pos_decode(struct pcache_cache *cache,
+ struct pcache_cache_pos_onmedia *pos_onmedia,
+ struct pcache_cache_pos *pos, u64 *seq, u32 *index)
+{
+ struct pcache_cache_pos_onmedia latest, *latest_addr;
+
+ latest_addr = pcache_meta_find_latest(&pos_onmedia->header,
+ sizeof(struct pcache_cache_pos_onmedia),
+ sizeof(struct pcache_cache_pos_onmedia),
+ &latest);
+ if (IS_ERR(latest_addr))
+ return PTR_ERR(latest_addr);
+
+ if (!latest_addr)
+ return -EIO;
+
+ if (!cache_seg_id_valid(cache, latest.cache_seg_id))
+ return -EIO;
+
+ pos->cache_seg = &cache->segments[latest.cache_seg_id];
+
+ if (latest.seg_off >= pos->cache_seg->segment.data_size)
+ return -EIO;
+
+ pos->seg_off = latest.seg_off;
+ *seq = latest.header.seq;
+ *index = (latest_addr - pos_onmedia);
+
+ return 0;
+}
+
+static inline void cache_info_set_seg_id(struct pcache_cache *cache, u32 seg_id)
+{
+ cache->cache_info.seg_id = seg_id;
+}
+
+static int cache_init(struct dm_pcache *pcache)
+{
+ struct pcache_cache *cache = &pcache->cache;
+ struct pcache_backing_dev *backing_dev = &pcache->backing_dev;
+ struct pcache_cache_dev *cache_dev = &pcache->cache_dev;
+ int ret;
+
+ cache->segments = kvzalloc_objs(struct pcache_cache_segment,
+ cache_dev->seg_num);
+ if (!cache->segments) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ cache->seg_map = kvcalloc(BITS_TO_LONGS(cache_dev->seg_num), sizeof(unsigned long), GFP_KERNEL);
+ if (!cache->seg_map) {
+ ret = -ENOMEM;
+ goto free_segments;
+ }
+
+ cache->backing_dev = backing_dev;
+ cache->cache_dev = &pcache->cache_dev;
+ cache->n_segs = cache_dev->seg_num;
+ atomic_set(&cache->gc_errors, 0);
+ atomic_set(&cache->writeback_errors, 0);
+ spin_lock_init(&cache->seg_map_lock);
+ spin_lock_init(&cache->key_head_lock);
+
+ mutex_init(&cache->cache_info_lock);
+ mutex_init(&cache->key_tail_lock);
+ mutex_init(&cache->dirty_tail_lock);
+ mutex_init(&cache->writeback_lock);
+
+ INIT_DELAYED_WORK(&cache->writeback_work, cache_writeback_fn);
+ INIT_DELAYED_WORK(&cache->gc_work, pcache_cache_gc_fn);
+ INIT_WORK(&cache->clean_work, clean_fn);
+
+ return 0;
+
+free_segments:
+ kvfree(cache->segments);
+err:
+ return ret;
+}
+
+static void cache_exit(struct pcache_cache *cache)
+{
+ kvfree(cache->seg_map);
+ kvfree(cache->segments);
+}
+
+static void cache_info_init_default(struct pcache_cache *cache)
+{
+ struct pcache_cache_info *cache_info = &cache->cache_info;
+
+ memset(cache_info, 0, sizeof(*cache_info));
+ cache_info->n_segs = cache->cache_dev->seg_num;
+ cache_info_set_gc_percent(cache_info, PCACHE_CACHE_GC_PERCENT_DEFAULT);
+}
+
+static int cache_tail_init(struct pcache_cache *cache)
+{
+ struct dm_pcache *pcache = CACHE_TO_PCACHE(cache);
+ bool new_cache = !(cache->cache_info.flags & PCACHE_CACHE_FLAGS_INIT_DONE);
+ int ret;
+
+ if (new_cache) {
+ __set_bit(0, cache->seg_map);
+
+ cache->key_head.cache_seg = &cache->segments[0];
+ cache->key_head.seg_off = 0;
+ cache_pos_copy(&cache->key_tail, &cache->key_head);
+ cache_pos_copy(&cache->dirty_tail, &cache->key_head);
+
+ cache_encode_dirty_tail(cache);
+ cache_encode_key_tail(cache);
+ } else {
+ if (cache_decode_key_tail(cache) || cache_decode_dirty_tail(cache)) {
+ pcache_dev_err(pcache, "Corrupted key tail or dirty tail.\n");
+ return -EIO;
+ }
+
+ ret = cache_verify_dirty_tail(cache);
+ if (ret) {
+ pcache_dev_err(pcache, "dirty tail chain does not terminate (crafted cache image?)\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int get_seg_id(struct pcache_cache *cache,
+ struct pcache_cache_segment *prev_cache_seg,
+ bool new_cache, u32 *seg_id)
+{
+ struct dm_pcache *pcache = CACHE_TO_PCACHE(cache);
+ struct pcache_cache_dev *cache_dev = cache->cache_dev;
+ int ret;
+
+ if (new_cache) {
+ ret = cache_dev_get_empty_segment_id(cache_dev, seg_id);
+ if (ret) {
+ pcache_dev_err(pcache, "no available segment\n");
+ goto err;
+ }
+
+ if (prev_cache_seg)
+ cache_seg_set_next_seg(prev_cache_seg, *seg_id);
+ else
+ cache_info_set_seg_id(cache, *seg_id);
+ } else {
+ if (prev_cache_seg) {
+ struct pcache_segment_info *prev_seg_info;
+
+ prev_seg_info = &prev_cache_seg->cache_seg_info;
+ if (!segment_info_has_next(prev_seg_info)) {
+ ret = -EFAULT;
+ goto err;
+ }
+ *seg_id = prev_cache_seg->cache_seg_info.next_seg;
+ } else {
+ *seg_id = cache->cache_info.seg_id;
+ }
+
+ if (*seg_id >= cache_dev->seg_num) {
+ pcache_dev_err(pcache, "invalid segment id %u from cache device (seg_num %u)\n",
+ *seg_id, cache_dev->seg_num);
+ ret = -EIO;
+ goto err;
+ }
+ }
+ return 0;
+err:
+ return ret;
+}
+
+static int cache_segs_init(struct pcache_cache *cache)
+{
+ struct pcache_cache_segment *prev_cache_seg = NULL;
+ struct pcache_cache_info *cache_info = &cache->cache_info;
+ bool new_cache = !(cache->cache_info.flags & PCACHE_CACHE_FLAGS_INIT_DONE);
+ u32 seg_id;
+ int ret;
+ u32 i;
+
+ if (cache_info->n_segs > cache->cache_dev->seg_num) {
+ pcache_dev_err(CACHE_TO_PCACHE(cache),
+ "cache_info n_segs %u exceeds cache device segments %u\n",
+ cache_info->n_segs, cache->cache_dev->seg_num);
+ return -EIO;
+ }
+
+ for (i = 0; i < cache_info->n_segs; i++) {
+ ret = get_seg_id(cache, prev_cache_seg, new_cache, &seg_id);
+ if (ret)
+ goto err;
+
+ ret = cache_seg_init(cache, seg_id, i, new_cache);
+ if (ret)
+ goto err;
+
+ prev_cache_seg = &cache->segments[i];
+ }
+ return 0;
+err:
+ return ret;
+}
+
+static int cache_init_req_keys(struct pcache_cache *cache, u32 n_paral)
+{
+ struct dm_pcache *pcache = CACHE_TO_PCACHE(cache);
+ u32 n_subtrees;
+ int ret;
+ u32 i, cpu;
+
+ /* Calculate number of cache trees based on the device size */
+ n_subtrees = DIV_ROUND_UP(cache->dev_size << SECTOR_SHIFT, PCACHE_CACHE_SUBTREE_SIZE);
+ ret = cache_tree_init(cache, &cache->req_key_tree, n_subtrees);
+ if (ret)
+ goto err;
+
+ cache->n_ksets = n_paral;
+ cache->ksets = kvcalloc(cache->n_ksets, PCACHE_KSET_SIZE, GFP_KERNEL);
+ if (!cache->ksets) {
+ ret = -ENOMEM;
+ goto req_tree_exit;
+ }
+
+ /*
+ * Initialize each kset with a spinlock and delayed work for flushing.
+ * Each kset is associated with one queue to ensure independent handling
+ * of cache keys across multiple queues, maximizing multiqueue concurrency.
+ */
+ for (i = 0; i < cache->n_ksets; i++) {
+ struct pcache_cache_kset *kset = get_kset(cache, i);
+
+ kset->cache = cache;
+ spin_lock_init(&kset->kset_lock);
+ INIT_DELAYED_WORK(&kset->flush_work, kset_flush_fn);
+ }
+
+ cache->data_heads = alloc_percpu(struct pcache_cache_data_head);
+ if (!cache->data_heads) {
+ ret = -ENOMEM;
+ goto free_kset;
+ }
+
+ for_each_possible_cpu(cpu) {
+ struct pcache_cache_data_head *h =
+ per_cpu_ptr(cache->data_heads, cpu);
+ h->head_pos.cache_seg = NULL;
+ }
+
+ /*
+ * Replay persisted cache keys using cache_replay.
+ * This function loads and replays cache keys from previously stored
+ * ksets, allowing the cache to restore its state after a restart.
+ */
+ ret = cache_replay(cache);
+ if (ret) {
+ pcache_dev_err(pcache, "failed to replay keys\n");
+ goto free_heads;
+ }
+
+ return 0;
+
+free_heads:
+ free_percpu(cache->data_heads);
+free_kset:
+ kvfree(cache->ksets);
+req_tree_exit:
+ cache_tree_exit(&cache->req_key_tree);
+err:
+ return ret;
+}
+
+static void cache_destroy_req_keys(struct pcache_cache *cache)
+{
+ u32 i;
+
+ for (i = 0; i < cache->n_ksets; i++) {
+ struct pcache_cache_kset *kset = get_kset(cache, i);
+
+ cancel_delayed_work_sync(&kset->flush_work);
+ }
+
+ free_percpu(cache->data_heads);
+ kvfree(cache->ksets);
+ cache_tree_exit(&cache->req_key_tree);
+}
+
+int pcache_cache_start(struct dm_pcache *pcache)
+{
+ struct pcache_backing_dev *backing_dev = &pcache->backing_dev;
+ struct pcache_cache *cache = &pcache->cache;
+ struct pcache_cache_options *opts = &pcache->opts;
+ int ret;
+
+ ret = cache_init(pcache);
+ if (ret)
+ return ret;
+
+ cache->cache_info_addr = CACHE_DEV_CACHE_INFO(cache->cache_dev);
+ cache->cache_ctrl = CACHE_DEV_CACHE_CTRL(cache->cache_dev);
+ backing_dev->cache = cache;
+ cache->dev_size = backing_dev->dev_size;
+
+ ret = cache_info_init(cache, opts);
+ if (ret)
+ goto cache_exit;
+
+ ret = cache_segs_init(cache);
+ if (ret)
+ goto cache_exit;
+
+ ret = cache_tail_init(cache);
+ if (ret)
+ goto cache_exit;
+
+ ret = cache_init_req_keys(cache, num_online_cpus());
+ if (ret)
+ goto cache_exit;
+
+ ret = cache_writeback_init(cache);
+ if (ret)
+ goto destroy_keys;
+
+ cache->cache_info.flags |= PCACHE_CACHE_FLAGS_INIT_DONE;
+ cache_info_write(cache);
+ queue_delayed_work(cache_get_wq(cache), &cache->gc_work, 0);
+
+ return 0;
+
+destroy_keys:
+ cache_destroy_req_keys(cache);
+cache_exit:
+ cache_exit(cache);
+
+ return ret;
+}
+
+void pcache_cache_stop(struct dm_pcache *pcache)
+{
+ struct pcache_cache *cache = &pcache->cache;
+
+ pcache_cache_flush(cache);
+
+ cancel_delayed_work_sync(&cache->gc_work);
+ flush_work(&cache->clean_work);
+ cache_writeback_exit(cache);
+
+ if (cache->req_key_tree.n_subtrees)
+ cache_destroy_req_keys(cache);
+
+ cache_exit(cache);
+}
+
+struct workqueue_struct *cache_get_wq(struct pcache_cache *cache)
+{
+ struct dm_pcache *pcache = CACHE_TO_PCACHE(cache);
+
+ return pcache->task_wq;
+}
+
+int pcache_cache_init(void)
+{
+ key_cache = KMEM_CACHE(pcache_cache_key, 0);
+ if (!key_cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void pcache_cache_exit(void)
+{
+ kmem_cache_destroy(key_cache);
+}