^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * zswap.c - zswap driver file
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * zswap is a backend for frontswap that takes pages that are in the process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * of being swapped out and attempts to compress and store them in a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * RAM-based memory pool. This can result in a significant I/O reduction on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * the swap device and, in the case where decompressing from RAM is faster
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * than reading from the swap device, can also improve workload performance.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * Copyright (C) 2012 Seth Jennings <sjenning@linux.vnet.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/cpu.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/highmem.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/spinlock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/atomic.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/frontswap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/rbtree.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <linux/swap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/crypto.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <linux/mempool.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <linux/zpool.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include <linux/mm_types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/page-flags.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <linux/swapops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <linux/writeback.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <linux/pagemap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) #include <linux/workqueue.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * statistics
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) /* Total bytes used by the compressed storage */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) static u64 zswap_pool_total_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) /* The number of compressed pages currently stored in zswap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) static atomic_t zswap_stored_pages = ATOMIC_INIT(0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) /* The number of same-value filled pages currently stored in zswap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static atomic_t zswap_same_filled_pages = ATOMIC_INIT(0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * The statistics below are not protected from concurrent access for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * performance reasons so they may not be a 100% accurate. However,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) * they do provide useful information on roughly how many times a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * certain event is occurring.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) /* Pool limit was hit (see zswap_max_pool_percent) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static u64 zswap_pool_limit_hit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) /* Pages written back when pool limit was reached */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) static u64 zswap_written_back_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /* Store failed due to a reclaim failure after pool limit was reached */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) static u64 zswap_reject_reclaim_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) /* Compressed page was too big for the allocator to (optimally) store */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) static u64 zswap_reject_compress_poor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /* Store failed because underlying allocator could not get memory */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) static u64 zswap_reject_alloc_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) /* Store failed because the entry metadata could not be allocated (rare) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) static u64 zswap_reject_kmemcache_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) /* Duplicate store was encountered (rare) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static u64 zswap_duplicate_entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) /* Shrinker work queue */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static struct workqueue_struct *shrink_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) /* Pool limit was hit, we need to calm down */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) static bool zswap_pool_reached_full;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) * tunables
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) #define ZSWAP_PARAM_UNSET ""
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) /* Enable/disable zswap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) static bool zswap_enabled = IS_ENABLED(CONFIG_ZSWAP_DEFAULT_ON);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) static int zswap_enabled_param_set(const char *,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) const struct kernel_param *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) static struct kernel_param_ops zswap_enabled_param_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) .set = zswap_enabled_param_set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) .get = param_get_bool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) module_param_cb(enabled, &zswap_enabled_param_ops, &zswap_enabled, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) /* Crypto compressor to use */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) static char *zswap_compressor = CONFIG_ZSWAP_COMPRESSOR_DEFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) static int zswap_compressor_param_set(const char *,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) const struct kernel_param *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) static struct kernel_param_ops zswap_compressor_param_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) .set = zswap_compressor_param_set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) .get = param_get_charp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) .free = param_free_charp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) module_param_cb(compressor, &zswap_compressor_param_ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) &zswap_compressor, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* Compressed storage zpool to use */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) static char *zswap_zpool_type = CONFIG_ZSWAP_ZPOOL_DEFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static int zswap_zpool_param_set(const char *, const struct kernel_param *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) static struct kernel_param_ops zswap_zpool_param_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) .set = zswap_zpool_param_set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) .get = param_get_charp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) .free = param_free_charp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) module_param_cb(zpool, &zswap_zpool_param_ops, &zswap_zpool_type, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) /* The maximum percentage of memory that the compressed pool can occupy */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) static unsigned int zswap_max_pool_percent = 20;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) module_param_named(max_pool_percent, zswap_max_pool_percent, uint, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) /* The threshold for accepting new pages after the max_pool_percent was hit */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) static unsigned int zswap_accept_thr_percent = 90; /* of max pool size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) module_param_named(accept_threshold_percent, zswap_accept_thr_percent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) uint, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) /* Enable/disable handling same-value filled pages (enabled by default) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) static bool zswap_same_filled_pages_enabled = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) module_param_named(same_filled_pages_enabled, zswap_same_filled_pages_enabled,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) bool, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) * data structures
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) struct zswap_pool {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) struct zpool *zpool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) struct crypto_comp * __percpu *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) struct kref kref;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct list_head list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) struct work_struct release_work;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) struct work_struct shrink_work;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) struct hlist_node node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) char tfm_name[CRYPTO_MAX_ALG_NAME];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * struct zswap_entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) * This structure contains the metadata for tracking a single compressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) * page within zswap.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) * rbnode - links the entry into red-black tree for the appropriate swap type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) * offset - the swap offset for the entry. Index into the red-black tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) * refcount - the number of outstanding reference to the entry. This is needed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) * to protect against premature freeing of the entry by code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) * concurrent calls to load, invalidate, and writeback. The lock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) * for the zswap_tree structure that contains the entry must
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) * be held while changing the refcount. Since the lock must
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) * be held, there is no reason to also make refcount atomic.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) * length - the length in bytes of the compressed page data. Needed during
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) * decompression. For a same value filled page length is 0.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) * pool - the zswap_pool the entry's data is in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) * handle - zpool allocation handle that stores the compressed page data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) * value - value of the same-value filled pages which have same content
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) struct zswap_entry {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) struct rb_node rbnode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) pgoff_t offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) int refcount;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) unsigned int length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) union {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) unsigned long handle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) unsigned long value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) struct zswap_header {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) swp_entry_t swpentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) * The tree lock in the zswap_tree struct protects a few things:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) * - the rbtree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) * - the refcount field of each entry in the tree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) struct zswap_tree {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) struct rb_root rbroot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) spinlock_t lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) static struct zswap_tree *zswap_trees[MAX_SWAPFILES];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) /* RCU-protected iteration */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) static LIST_HEAD(zswap_pools);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) /* protects zswap_pools list modification */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) static DEFINE_SPINLOCK(zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) /* pool counter to provide unique names to zpool */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) static atomic_t zswap_pools_count = ATOMIC_INIT(0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) /* used by param callback function */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) static bool zswap_init_started;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) /* fatal error during init */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) static bool zswap_init_failed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) /* init completed, but couldn't create the initial pool */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) static bool zswap_has_pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) * helpers and fwd declarations
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) #define zswap_pool_debug(msg, p) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) pr_debug("%s pool %s/%s\n", msg, (p)->tfm_name, \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) zpool_get_type((p)->zpool))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) static int zswap_writeback_entry(struct zpool *pool, unsigned long handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) static int zswap_pool_get(struct zswap_pool *pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) static void zswap_pool_put(struct zswap_pool *pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) static const struct zpool_ops zswap_zpool_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) .evict = zswap_writeback_entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) static bool zswap_is_full(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) return totalram_pages() * zswap_max_pool_percent / 100 <
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) static bool zswap_can_accept(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) return totalram_pages() * zswap_accept_thr_percent / 100 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) zswap_max_pool_percent / 100 >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) static void zswap_update_total_size(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) u64 total = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) list_for_each_entry_rcu(pool, &zswap_pools, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) total += zpool_get_total_size(pool->zpool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) zswap_pool_total_size = total;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) * zswap entry functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) static struct kmem_cache *zswap_entry_cache;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) static int __init zswap_entry_cache_create(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) zswap_entry_cache = KMEM_CACHE(zswap_entry, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) return zswap_entry_cache == NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) static void __init zswap_entry_cache_destroy(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) kmem_cache_destroy(zswap_entry_cache);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) static struct zswap_entry *zswap_entry_cache_alloc(gfp_t gfp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) entry = kmem_cache_alloc(zswap_entry_cache, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) if (!entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) entry->refcount = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) RB_CLEAR_NODE(&entry->rbnode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) return entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) static void zswap_entry_cache_free(struct zswap_entry *entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) kmem_cache_free(zswap_entry_cache, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) * rbtree functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) static struct zswap_entry *zswap_rb_search(struct rb_root *root, pgoff_t offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) struct rb_node *node = root->rb_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) while (node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) entry = rb_entry(node, struct zswap_entry, rbnode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) if (entry->offset > offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) node = node->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) else if (entry->offset < offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) node = node->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) return entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) * In the case that a entry with the same offset is found, a pointer to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) * the existing entry is stored in dupentry and the function returns -EEXIST
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) static int zswap_rb_insert(struct rb_root *root, struct zswap_entry *entry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) struct zswap_entry **dupentry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) struct rb_node **link = &root->rb_node, *parent = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) struct zswap_entry *myentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) while (*link) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) parent = *link;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) myentry = rb_entry(parent, struct zswap_entry, rbnode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) if (myentry->offset > entry->offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) link = &(*link)->rb_left;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) else if (myentry->offset < entry->offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) link = &(*link)->rb_right;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) *dupentry = myentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) return -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) rb_link_node(&entry->rbnode, parent, link);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) rb_insert_color(&entry->rbnode, root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) static void zswap_rb_erase(struct rb_root *root, struct zswap_entry *entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) if (!RB_EMPTY_NODE(&entry->rbnode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) rb_erase(&entry->rbnode, root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) RB_CLEAR_NODE(&entry->rbnode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) * Carries out the common pattern of freeing and entry's zpool allocation,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) * freeing the entry itself, and decrementing the number of stored pages.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) static void zswap_free_entry(struct zswap_entry *entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) if (!entry->length)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) atomic_dec(&zswap_same_filled_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) zpool_free(entry->pool->zpool, entry->handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) zswap_pool_put(entry->pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) zswap_entry_cache_free(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) atomic_dec(&zswap_stored_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) zswap_update_total_size();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) /* caller must hold the tree lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) static void zswap_entry_get(struct zswap_entry *entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) entry->refcount++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) /* caller must hold the tree lock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) * remove from the tree and free it, if nobody reference the entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) static void zswap_entry_put(struct zswap_tree *tree,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) struct zswap_entry *entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) int refcount = --entry->refcount;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) BUG_ON(refcount < 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) if (refcount == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) zswap_rb_erase(&tree->rbroot, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) zswap_free_entry(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) /* caller must hold the tree lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) static struct zswap_entry *zswap_entry_find_get(struct rb_root *root,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) pgoff_t offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) entry = zswap_rb_search(root, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) if (entry)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) zswap_entry_get(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) return entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) * per-cpu code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) static DEFINE_PER_CPU(u8 *, zswap_dstmem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) static int zswap_dstmem_prepare(unsigned int cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) u8 *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) dst = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) if (!dst)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) per_cpu(zswap_dstmem, cpu) = dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) static int zswap_dstmem_dead(unsigned int cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) u8 *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) dst = per_cpu(zswap_dstmem, cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) kfree(dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) per_cpu(zswap_dstmem, cpu) = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) struct crypto_comp *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) if (WARN_ON(*per_cpu_ptr(pool->tfm, cpu)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) tfm = crypto_alloc_comp(pool->tfm_name, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) if (IS_ERR_OR_NULL(tfm)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) pr_err("could not alloc crypto comp %s : %ld\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) pool->tfm_name, PTR_ERR(tfm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) *per_cpu_ptr(pool->tfm, cpu) = tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) struct crypto_comp *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) tfm = *per_cpu_ptr(pool->tfm, cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) if (!IS_ERR_OR_NULL(tfm))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) crypto_free_comp(tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) *per_cpu_ptr(pool->tfm, cpu) = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) * pool functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) static struct zswap_pool *__zswap_pool_current(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) pool = list_first_or_null_rcu(&zswap_pools, typeof(*pool), list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) WARN_ONCE(!pool && zswap_has_pool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) "%s: no page storage pool!\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) return pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) static struct zswap_pool *zswap_pool_current(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) assert_spin_locked(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) return __zswap_pool_current();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) static struct zswap_pool *zswap_pool_current_get(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) pool = __zswap_pool_current();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) if (!zswap_pool_get(pool))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) pool = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) return pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) static struct zswap_pool *zswap_pool_last_get(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) struct zswap_pool *pool, *last = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) list_for_each_entry_rcu(pool, &zswap_pools, list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) last = pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) WARN_ONCE(!last && zswap_has_pool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) "%s: no page storage pool!\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) if (!zswap_pool_get(last))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) last = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) return last;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) /* type and compressor must be null-terminated */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) assert_spin_locked(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) list_for_each_entry_rcu(pool, &zswap_pools, list) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) if (strcmp(pool->tfm_name, compressor))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) if (strcmp(zpool_get_type(pool->zpool), type))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) /* if we can't get it, it's about to be destroyed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) if (!zswap_pool_get(pool))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) return pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) static void shrink_worker(struct work_struct *w)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) struct zswap_pool *pool = container_of(w, typeof(*pool),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) shrink_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) if (zpool_shrink(pool->zpool, 1, NULL))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) zswap_reject_reclaim_fail++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) zswap_pool_put(pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) char name[38]; /* 'zswap' + 32 char (max) num + \0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) if (!zswap_has_pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) /* if either are unset, pool initialization failed, and we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) * need both params to be set correctly before trying to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) * create a pool.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) if (!strcmp(type, ZSWAP_PARAM_UNSET))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) if (!strcmp(compressor, ZSWAP_PARAM_UNSET))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) pool = kzalloc(sizeof(*pool), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) if (!pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) /* unique name for each pool specifically required by zsmalloc */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) snprintf(name, 38, "zswap%x", atomic_inc_return(&zswap_pools_count));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) pool->zpool = zpool_create_pool(type, name, gfp, &zswap_zpool_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) if (!pool->zpool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) pr_err("%s zpool not available\n", type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) pr_debug("using %s zpool\n", zpool_get_type(pool->zpool));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) strlcpy(pool->tfm_name, compressor, sizeof(pool->tfm_name));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) pool->tfm = alloc_percpu(struct crypto_comp *);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) if (!pool->tfm) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) pr_err("percpu alloc failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) ret = cpuhp_state_add_instance(CPUHP_MM_ZSWP_POOL_PREPARE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) &pool->node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) pr_debug("using %s compressor\n", pool->tfm_name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) /* being the current pool takes 1 ref; this func expects the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) * caller to always add the new pool as the current pool
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) kref_init(&pool->kref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) INIT_LIST_HEAD(&pool->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) INIT_WORK(&pool->shrink_work, shrink_worker);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) zswap_pool_debug("created", pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) return pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) free_percpu(pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) if (pool->zpool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) zpool_destroy_pool(pool->zpool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) kfree(pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) static __init struct zswap_pool *__zswap_pool_create_fallback(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) bool has_comp, has_zpool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) has_comp = crypto_has_comp(zswap_compressor, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) if (!has_comp && strcmp(zswap_compressor,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) CONFIG_ZSWAP_COMPRESSOR_DEFAULT)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) pr_err("compressor %s not available, using default %s\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) zswap_compressor, CONFIG_ZSWAP_COMPRESSOR_DEFAULT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) param_free_charp(&zswap_compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) zswap_compressor = CONFIG_ZSWAP_COMPRESSOR_DEFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) has_comp = crypto_has_comp(zswap_compressor, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) if (!has_comp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) pr_err("default compressor %s not available\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) zswap_compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) param_free_charp(&zswap_compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) zswap_compressor = ZSWAP_PARAM_UNSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) has_zpool = zpool_has_pool(zswap_zpool_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) if (!has_zpool && strcmp(zswap_zpool_type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) CONFIG_ZSWAP_ZPOOL_DEFAULT)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) pr_err("zpool %s not available, using default %s\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) zswap_zpool_type, CONFIG_ZSWAP_ZPOOL_DEFAULT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) param_free_charp(&zswap_zpool_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) zswap_zpool_type = CONFIG_ZSWAP_ZPOOL_DEFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622) has_zpool = zpool_has_pool(zswap_zpool_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) if (!has_zpool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) pr_err("default zpool %s not available\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) zswap_zpool_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) param_free_charp(&zswap_zpool_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) zswap_zpool_type = ZSWAP_PARAM_UNSET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) if (!has_comp || !has_zpool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) return zswap_pool_create(zswap_zpool_type, zswap_compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) static void zswap_pool_destroy(struct zswap_pool *pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) zswap_pool_debug("destroying", pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) cpuhp_state_remove_instance(CPUHP_MM_ZSWP_POOL_PREPARE, &pool->node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) free_percpu(pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) zpool_destroy_pool(pool->zpool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) kfree(pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) static int __must_check zswap_pool_get(struct zswap_pool *pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) if (!pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) return kref_get_unless_zero(&pool->kref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) static void __zswap_pool_release(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) struct zswap_pool *pool = container_of(work, typeof(*pool),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) release_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) synchronize_rcu();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) /* nobody should have been able to get a kref... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) WARN_ON(kref_get_unless_zero(&pool->kref));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) /* pool is now off zswap_pools list and has no references. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) zswap_pool_destroy(pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) static void __zswap_pool_empty(struct kref *kref)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) pool = container_of(kref, typeof(*pool), kref);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675) spin_lock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) WARN_ON(pool == zswap_pool_current());
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) list_del_rcu(&pool->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) INIT_WORK(&pool->release_work, __zswap_pool_release);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) schedule_work(&pool->release_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) spin_unlock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) static void zswap_pool_put(struct zswap_pool *pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) kref_put(&pool->kref, __zswap_pool_empty);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) * param callbacks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) /* val must be a null-terminated string */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) static int __zswap_param_set(const char *val, const struct kernel_param *kp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) char *type, char *compressor)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) struct zswap_pool *pool, *put_pool = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) char *s = strstrip((char *)val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) if (zswap_init_failed) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) pr_err("can't set param, initialization failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) /* no change required */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) if (!strcmp(s, *(char **)kp->arg) && zswap_has_pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) /* if this is load-time (pre-init) param setting,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) * don't create a pool; that's done during init.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) if (!zswap_init_started)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) return param_set_charp(s, kp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) if (!type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) if (!zpool_has_pool(s)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) pr_err("zpool %s not available\n", s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) return -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724) type = s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) } else if (!compressor) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) if (!crypto_has_comp(s, 0, 0)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) pr_err("compressor %s not available\n", s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) return -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) compressor = s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) WARN_ON(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) spin_lock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) pool = zswap_pool_find_get(type, compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) if (pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) zswap_pool_debug("using existing", pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) WARN_ON(pool == zswap_pool_current());
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) list_del_rcu(&pool->list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) spin_unlock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) if (!pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) pool = zswap_pool_create(type, compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) if (pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) ret = param_set_charp(s, kp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) spin_lock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) if (!ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) put_pool = zswap_pool_current();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) list_add_rcu(&pool->list, &zswap_pools);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) zswap_has_pool = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) } else if (pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) /* add the possibly pre-existing pool to the end of the pools
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) * list; if it's new (and empty) then it'll be removed and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) * destroyed by the put after we drop the lock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) list_add_tail_rcu(&pool->list, &zswap_pools);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) put_pool = pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) spin_unlock(&zswap_pools_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772) if (!zswap_has_pool && !pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) /* if initial pool creation failed, and this pool creation also
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) * failed, maybe both compressor and zpool params were bad.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) * Allow changing this param, so pool creation will succeed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) * when the other param is changed. We already verified this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777) * param is ok in the zpool_has_pool() or crypto_has_comp()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) * checks above.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) ret = param_set_charp(s, kp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) /* drop the ref from either the old current pool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) * or the new pool we failed to add
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) if (put_pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) zswap_pool_put(put_pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) static int zswap_compressor_param_set(const char *val,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793) const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) return __zswap_param_set(val, kp, zswap_zpool_type, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) static int zswap_zpool_param_set(const char *val,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799) const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) return __zswap_param_set(val, kp, NULL, zswap_compressor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) static int zswap_enabled_param_set(const char *val,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) if (zswap_init_failed) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) pr_err("can't enable, initialization failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) if (!zswap_has_pool && zswap_init_started) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) pr_err("can't enable, no pool configured\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) return param_set_bool(val, kp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) * writeback code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) /* return enum for zswap_get_swap_cache_page */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) enum zswap_get_swap_ret {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) ZSWAP_SWAPCACHE_NEW,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) ZSWAP_SWAPCACHE_EXIST,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) ZSWAP_SWAPCACHE_FAIL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) * zswap_get_swap_cache_page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) * This is an adaption of read_swap_cache_async()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) * This function tries to find a page with the given swap entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) * in the swapper_space address space (the swap cache). If the page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) * is found, it is returned in retpage. Otherwise, a page is allocated,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) * added to the swap cache, and returned in retpage.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 838) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 839) * If success, the swap cache page is returned in retpage
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 840) * Returns ZSWAP_SWAPCACHE_EXIST if page was already in the swap cache
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 841) * Returns ZSWAP_SWAPCACHE_NEW if the new page needs to be populated,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 842) * the new page is added to swapcache and locked
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 843) * Returns ZSWAP_SWAPCACHE_FAIL on error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 844) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 845) static int zswap_get_swap_cache_page(swp_entry_t entry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 846) struct page **retpage)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 847) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 848) bool page_was_allocated;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 849)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 850) *retpage = __read_swap_cache_async(entry, GFP_KERNEL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 851) NULL, 0, &page_was_allocated);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 852) if (page_was_allocated)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 853) return ZSWAP_SWAPCACHE_NEW;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 854) if (!*retpage)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 855) return ZSWAP_SWAPCACHE_FAIL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 856) return ZSWAP_SWAPCACHE_EXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 857) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 858)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 859) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 860) * Attempts to free an entry by adding a page to the swap cache,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 861) * decompressing the entry data into the page, and issuing a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 862) * bio write to write the page back to the swap device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 863) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 864) * This can be thought of as a "resumed writeback" of the page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 865) * to the swap device. We are basically resuming the same swap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 866) * writeback path that was intercepted with the frontswap_store()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 867) * in the first place. After the page has been decompressed into
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 868) * the swap cache, the compressed version stored by zswap can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 869) * freed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 870) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 871) static int zswap_writeback_entry(struct zpool *pool, unsigned long handle)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 872) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 873) struct zswap_header *zhdr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 874) swp_entry_t swpentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 875) struct zswap_tree *tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 876) pgoff_t offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 877) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 878) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 879) struct crypto_comp *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 880) u8 *src, *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 881) unsigned int dlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 882) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 883) struct writeback_control wbc = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 884) .sync_mode = WB_SYNC_NONE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 885) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 886)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 887) /* extract swpentry from data */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 888) zhdr = zpool_map_handle(pool, handle, ZPOOL_MM_RO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 889) swpentry = zhdr->swpentry; /* here */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 890) tree = zswap_trees[swp_type(swpentry)];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 891) offset = swp_offset(swpentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 892)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 893) /* find and ref zswap entry */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 894) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 895) entry = zswap_entry_find_get(&tree->rbroot, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 896) if (!entry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 897) /* entry was invalidated */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 898) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 899) zpool_unmap_handle(pool, handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 900) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 901) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 902) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 903) BUG_ON(offset != entry->offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 904)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 905) /* try to allocate swap cache page */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 906) switch (zswap_get_swap_cache_page(swpentry, &page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 907) case ZSWAP_SWAPCACHE_FAIL: /* no memory or invalidate happened */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 908) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 909) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 910)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 911) case ZSWAP_SWAPCACHE_EXIST:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 912) /* page is already in the swap cache, ignore for now */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 913) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 914) ret = -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 915) goto fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 916)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 917) case ZSWAP_SWAPCACHE_NEW: /* page is locked */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 918) /* decompress */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 919) dlen = PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 920) src = (u8 *)zhdr + sizeof(struct zswap_header);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 921) dst = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 922) tfm = *get_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 923) ret = crypto_comp_decompress(tfm, src, entry->length,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 924) dst, &dlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 925) put_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 926) kunmap_atomic(dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 927) BUG_ON(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 928) BUG_ON(dlen != PAGE_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 929)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 930) /* page is up to date */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 931) SetPageUptodate(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 932) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 933)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 934) /* move it to the tail of the inactive list after end_writeback */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 935) SetPageReclaim(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 936)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 937) /* start writeback */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 938) __swap_writepage(page, &wbc, end_swap_bio_write);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 939) put_page(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 940) zswap_written_back_pages++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 941)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 942) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 943) /* drop local reference */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 944) zswap_entry_put(tree, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 945)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 946) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 947) * There are two possible situations for entry here:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 948) * (1) refcount is 1(normal case), entry is valid and on the tree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 949) * (2) refcount is 0, entry is freed and not on the tree
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 950) * because invalidate happened during writeback
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 951) * search the tree and free the entry if find entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 952) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 953) if (entry == zswap_rb_search(&tree->rbroot, offset))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 954) zswap_entry_put(tree, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 955) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 956)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 957) goto end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 958)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 959) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 960) * if we get here due to ZSWAP_SWAPCACHE_EXIST
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 961) * a load may happening concurrently
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 962) * it is safe and okay to not free the entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 963) * if we free the entry in the following put
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 964) * it it either okay to return !0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 965) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 966) fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 967) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 968) zswap_entry_put(tree, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 969) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 970)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 971) end:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 972) zpool_unmap_handle(pool, handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 973) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 974) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 975)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 976) static int zswap_is_page_same_filled(void *ptr, unsigned long *value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 977) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 978) unsigned int pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 979) unsigned long *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 980)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 981) page = (unsigned long *)ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 982) for (pos = 1; pos < PAGE_SIZE / sizeof(*page); pos++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 983) if (page[pos] != page[0])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 984) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 985) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 986) *value = page[0];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 987) return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 988) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 989)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 990) static void zswap_fill_page(void *ptr, unsigned long value)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 991) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 992) unsigned long *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 993)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 994) page = (unsigned long *)ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 995) memset_l(page, value, PAGE_SIZE / sizeof(unsigned long));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 996) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 997)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 998) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 999) * frontswap hooks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1000) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1001) /* attempts to compress and store an single page */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1002) static int zswap_frontswap_store(unsigned type, pgoff_t offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1003) struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1004) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1005) struct zswap_tree *tree = zswap_trees[type];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1006) struct zswap_entry *entry, *dupentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1007) struct crypto_comp *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1008) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1009) unsigned int hlen, dlen = PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1010) unsigned long handle, value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1011) char *buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1012) u8 *src, *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1013) struct zswap_header zhdr = { .swpentry = swp_entry(type, offset) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1014) gfp_t gfp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1015)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1016) /* THP isn't supported */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1017) if (PageTransHuge(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1018) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1019) goto reject;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1020) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1021)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1022) if (!zswap_enabled || !tree) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1023) ret = -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1024) goto reject;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1025) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1026)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1027) /* reclaim space if needed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1028) if (zswap_is_full()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1029) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1030)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1031) zswap_pool_limit_hit++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1032) zswap_pool_reached_full = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1033) pool = zswap_pool_last_get();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1034) if (pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1035) queue_work(shrink_wq, &pool->shrink_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1036) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1037) goto reject;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1038) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1039)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1040) if (zswap_pool_reached_full) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1041) if (!zswap_can_accept()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1042) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1043) goto reject;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1044) } else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1045) zswap_pool_reached_full = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1046) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1047)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1048) /* allocate entry */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1049) entry = zswap_entry_cache_alloc(GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1050) if (!entry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1051) zswap_reject_kmemcache_fail++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1052) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1053) goto reject;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1054) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1055)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1056) if (zswap_same_filled_pages_enabled) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1057) src = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1058) if (zswap_is_page_same_filled(src, &value)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1059) kunmap_atomic(src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1060) entry->offset = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1061) entry->length = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1062) entry->value = value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1063) atomic_inc(&zswap_same_filled_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1064) goto insert_entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1065) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1066) kunmap_atomic(src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1067) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1068)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1069) /* if entry is successfully added, it keeps the reference */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1070) entry->pool = zswap_pool_current_get();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1071) if (!entry->pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1072) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1073) goto freepage;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1074) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1075)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1076) /* compress */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1077) dst = get_cpu_var(zswap_dstmem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1078) tfm = *get_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1079) src = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1080) ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1081) kunmap_atomic(src);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1082) put_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1083) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1084) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1085) goto put_dstmem;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1086) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1087)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1088) /* store */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1089) hlen = zpool_evictable(entry->pool->zpool) ? sizeof(zhdr) : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1090) gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1091) if (zpool_malloc_support_movable(entry->pool->zpool))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1092) gfp |= __GFP_HIGHMEM | __GFP_MOVABLE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1093) ret = zpool_malloc(entry->pool->zpool, hlen + dlen, gfp, &handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1094) if (ret == -ENOSPC) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1095) zswap_reject_compress_poor++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1096) goto put_dstmem;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1097) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1098) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1099) zswap_reject_alloc_fail++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1100) goto put_dstmem;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1102) buf = zpool_map_handle(entry->pool->zpool, handle, ZPOOL_MM_RW);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1103) memcpy(buf, &zhdr, hlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1104) memcpy(buf + hlen, dst, dlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1105) zpool_unmap_handle(entry->pool->zpool, handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1106) put_cpu_var(zswap_dstmem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1108) /* populate entry */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1109) entry->offset = offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1110) entry->handle = handle;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1111) entry->length = dlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1113) insert_entry:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1114) /* map */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1115) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1116) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1117) ret = zswap_rb_insert(&tree->rbroot, entry, &dupentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1118) if (ret == -EEXIST) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1119) zswap_duplicate_entry++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1120) /* remove from rbtree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1121) zswap_rb_erase(&tree->rbroot, dupentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1122) zswap_entry_put(tree, dupentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1124) } while (ret == -EEXIST);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1125) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1127) /* update stats */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1128) atomic_inc(&zswap_stored_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1129) zswap_update_total_size();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1131) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1133) put_dstmem:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1134) put_cpu_var(zswap_dstmem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1135) zswap_pool_put(entry->pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1136) freepage:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1137) zswap_entry_cache_free(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1138) reject:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1139) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1140) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1142) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1143) * returns 0 if the page was successfully decompressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1144) * return -1 on entry not found or error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1145) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1146) static int zswap_frontswap_load(unsigned type, pgoff_t offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1147) struct page *page)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1148) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1149) struct zswap_tree *tree = zswap_trees[type];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1150) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1151) struct crypto_comp *tfm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1152) u8 *src, *dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1153) unsigned int dlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1154) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1156) /* find */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1157) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1158) entry = zswap_entry_find_get(&tree->rbroot, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1159) if (!entry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1160) /* entry was written back */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1161) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1162) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1163) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1164) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1166) if (!entry->length) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1167) dst = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1168) zswap_fill_page(dst, entry->value);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1169) kunmap_atomic(dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1170) goto freeentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1171) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1172)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1173) /* decompress */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1174) dlen = PAGE_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1175) src = zpool_map_handle(entry->pool->zpool, entry->handle, ZPOOL_MM_RO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1176) if (zpool_evictable(entry->pool->zpool))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1177) src += sizeof(struct zswap_header);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1178) dst = kmap_atomic(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1179) tfm = *get_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1180) ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1181) put_cpu_ptr(entry->pool->tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1182) kunmap_atomic(dst);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1183) zpool_unmap_handle(entry->pool->zpool, entry->handle);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1184) BUG_ON(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1185)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1186) freeentry:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1187) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1188) zswap_entry_put(tree, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1189) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1190)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1191) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1192) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1193)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1194) /* frees an entry in zswap */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1195) static void zswap_frontswap_invalidate_page(unsigned type, pgoff_t offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1196) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1197) struct zswap_tree *tree = zswap_trees[type];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1198) struct zswap_entry *entry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1199)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1200) /* find */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1201) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1202) entry = zswap_rb_search(&tree->rbroot, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1203) if (!entry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1204) /* entry was written back */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1205) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1206) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1207) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1208)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1209) /* remove from rbtree */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1210) zswap_rb_erase(&tree->rbroot, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1211)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1212) /* drop the initial reference from entry creation */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1213) zswap_entry_put(tree, entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1214)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1215) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1216) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1218) /* frees all zswap entries for the given swap type */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1219) static void zswap_frontswap_invalidate_area(unsigned type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1220) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1221) struct zswap_tree *tree = zswap_trees[type];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1222) struct zswap_entry *entry, *n;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1223)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1224) if (!tree)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1225) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1227) /* walk the tree and free everything */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1228) spin_lock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1229) rbtree_postorder_for_each_entry_safe(entry, n, &tree->rbroot, rbnode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1230) zswap_free_entry(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1231) tree->rbroot = RB_ROOT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1232) spin_unlock(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1233) kfree(tree);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1234) zswap_trees[type] = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1235) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1236)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1237) static void zswap_frontswap_init(unsigned type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1238) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1239) struct zswap_tree *tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1240)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1241) tree = kzalloc(sizeof(*tree), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1242) if (!tree) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1243) pr_err("alloc failed, zswap disabled for swap type %d\n", type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1244) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1245) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1247) tree->rbroot = RB_ROOT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1248) spin_lock_init(&tree->lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1249) zswap_trees[type] = tree;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1250) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1251)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1252) static struct frontswap_ops zswap_frontswap_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1253) .store = zswap_frontswap_store,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1254) .load = zswap_frontswap_load,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1255) .invalidate_page = zswap_frontswap_invalidate_page,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1256) .invalidate_area = zswap_frontswap_invalidate_area,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1257) .init = zswap_frontswap_init
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1258) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1260) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1261) * debugfs functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1262) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1263) #ifdef CONFIG_DEBUG_FS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1264) #include <linux/debugfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1266) static struct dentry *zswap_debugfs_root;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1268) static int __init zswap_debugfs_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1269) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1270) if (!debugfs_initialized())
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1271) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1272)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1273) zswap_debugfs_root = debugfs_create_dir("zswap", NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1274)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1275) debugfs_create_u64("pool_limit_hit", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1276) zswap_debugfs_root, &zswap_pool_limit_hit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1277) debugfs_create_u64("reject_reclaim_fail", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1278) zswap_debugfs_root, &zswap_reject_reclaim_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1279) debugfs_create_u64("reject_alloc_fail", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1280) zswap_debugfs_root, &zswap_reject_alloc_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1281) debugfs_create_u64("reject_kmemcache_fail", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1282) zswap_debugfs_root, &zswap_reject_kmemcache_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1283) debugfs_create_u64("reject_compress_poor", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1284) zswap_debugfs_root, &zswap_reject_compress_poor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1285) debugfs_create_u64("written_back_pages", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1286) zswap_debugfs_root, &zswap_written_back_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1287) debugfs_create_u64("duplicate_entry", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1288) zswap_debugfs_root, &zswap_duplicate_entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1289) debugfs_create_u64("pool_total_size", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1290) zswap_debugfs_root, &zswap_pool_total_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1291) debugfs_create_atomic_t("stored_pages", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1292) zswap_debugfs_root, &zswap_stored_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1293) debugfs_create_atomic_t("same_filled_pages", 0444,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1294) zswap_debugfs_root, &zswap_same_filled_pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1295)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1296) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1298)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1299) static void __exit zswap_debugfs_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1300) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1301) debugfs_remove_recursive(zswap_debugfs_root);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1302) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1303) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1304) static int __init zswap_debugfs_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1305) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1306) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1307) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1308)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1309) static void __exit zswap_debugfs_exit(void) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1310) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1311)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1312) /*********************************
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1313) * module init and exit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1314) **********************************/
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1315) static int __init init_zswap(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1316) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1317) struct zswap_pool *pool;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1318) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1319)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1320) zswap_init_started = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1321)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1322) if (zswap_entry_cache_create()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1323) pr_err("entry cache creation failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1324) goto cache_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1325) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1326)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1327) ret = cpuhp_setup_state(CPUHP_MM_ZSWP_MEM_PREPARE, "mm/zswap:prepare",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1328) zswap_dstmem_prepare, zswap_dstmem_dead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1329) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1330) pr_err("dstmem alloc failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1331) goto dstmem_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1332) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1334) ret = cpuhp_setup_state_multi(CPUHP_MM_ZSWP_POOL_PREPARE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1335) "mm/zswap_pool:prepare",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1336) zswap_cpu_comp_prepare,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1337) zswap_cpu_comp_dead);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1338) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1339) goto hp_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1340)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1341) pool = __zswap_pool_create_fallback();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1342) if (pool) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1343) pr_info("loaded using pool %s/%s\n", pool->tfm_name,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1344) zpool_get_type(pool->zpool));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1345) list_add(&pool->list, &zswap_pools);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1346) zswap_has_pool = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1347) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1348) pr_err("pool creation failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1349) zswap_enabled = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1350) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1351)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1352) shrink_wq = create_workqueue("zswap-shrink");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1353) if (!shrink_wq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1354) goto fallback_fail;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1355)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1356) frontswap_register_ops(&zswap_frontswap_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1357) if (zswap_debugfs_init())
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1358) pr_warn("debugfs initialization failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1359) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1360)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1361) fallback_fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1362) if (pool)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1363) zswap_pool_destroy(pool);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1364) hp_fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1365) cpuhp_remove_state(CPUHP_MM_ZSWP_MEM_PREPARE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1366) dstmem_fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1367) zswap_entry_cache_destroy();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1368) cache_fail:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1369) /* if built-in, we aren't unloaded on failure; don't allow use */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1370) zswap_init_failed = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1371) zswap_enabled = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1372) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1373) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1374) /* must be late so crypto has time to come up */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1375) late_initcall(init_zswap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1376)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1377) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1378) MODULE_AUTHOR("Seth Jennings <sjennings@variantweb.net>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1379) MODULE_DESCRIPTION("Compressed cache for swap pages");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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