c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 1) // SPDX-License-Identifier: GPL-2.0-or-later
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 2) /*
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 3) * linux/fs/fat/cache.c
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 4) *
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 5) * Written 1992,1993 by Werner Almesberger
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 6) *
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 7) * Mar 1999. AV. Changed cache, so that it uses the starting cluster instead
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 8) * of inode number.
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 9) * May 1999. AV. Fixed the bogosity with FAT32 (read "FAT28"). Fscking lusers.
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 10) * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 11) */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 12)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 13) #include <linux/slab.h>
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 14) #include <asm/unaligned.h>
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 15) #include <linux/buffer_head.h>
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 16)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 17) #include "exfat_raw.h"
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 18) #include "exfat_fs.h"
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 19)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 20) #define EXFAT_MAX_CACHE 16
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 21)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 22) struct exfat_cache {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 23) struct list_head cache_list;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 24) unsigned int nr_contig; /* number of contiguous clusters */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 25) unsigned int fcluster; /* cluster number in the file. */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 26) unsigned int dcluster; /* cluster number on disk. */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 27) };
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 28)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 29) struct exfat_cache_id {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 30) unsigned int id;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 31) unsigned int nr_contig;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 32) unsigned int fcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 33) unsigned int dcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 34) };
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 35)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 36) static struct kmem_cache *exfat_cachep;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 37)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 38) static void exfat_cache_init_once(void *c)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 39) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 40) struct exfat_cache *cache = (struct exfat_cache *)c;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 41)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 42) INIT_LIST_HEAD(&cache->cache_list);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 43) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 44)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 45) int exfat_cache_init(void)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 46) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 47) exfat_cachep = kmem_cache_create("exfat_cache",
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 48) sizeof(struct exfat_cache),
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 49) 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 50) exfat_cache_init_once);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 51) if (!exfat_cachep)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 52) return -ENOMEM;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 53) return 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 54) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 55)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 56) void exfat_cache_shutdown(void)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 57) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 58) if (!exfat_cachep)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 59) return;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 60) kmem_cache_destroy(exfat_cachep);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 61) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 62)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 63) static inline struct exfat_cache *exfat_cache_alloc(void)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 64) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 65) return kmem_cache_alloc(exfat_cachep, GFP_NOFS);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 66) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 67)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 68) static inline void exfat_cache_free(struct exfat_cache *cache)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 69) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 70) WARN_ON(!list_empty(&cache->cache_list));
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 71) kmem_cache_free(exfat_cachep, cache);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 72) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 73)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 74) static inline void exfat_cache_update_lru(struct inode *inode,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 75) struct exfat_cache *cache)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 76) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 77) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 78)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 79) if (ei->cache_lru.next != &cache->cache_list)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 80) list_move(&cache->cache_list, &ei->cache_lru);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 81) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 82)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 83) static unsigned int exfat_cache_lookup(struct inode *inode,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 84) unsigned int fclus, struct exfat_cache_id *cid,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 85) unsigned int *cached_fclus, unsigned int *cached_dclus)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 86) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 87) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 88) static struct exfat_cache nohit = { .fcluster = 0, };
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 89) struct exfat_cache *hit = &nohit, *p;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 90) unsigned int offset = EXFAT_EOF_CLUSTER;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 91)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 92) spin_lock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 93) list_for_each_entry(p, &ei->cache_lru, cache_list) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 94) /* Find the cache of "fclus" or nearest cache. */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 95) if (p->fcluster <= fclus && hit->fcluster < p->fcluster) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 96) hit = p;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 97) if (hit->fcluster + hit->nr_contig < fclus) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 98) offset = hit->nr_contig;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 99) } else {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 100) offset = fclus - hit->fcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 101) break;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 102) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 103) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 104) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 105) if (hit != &nohit) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 106) exfat_cache_update_lru(inode, hit);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 107)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 108) cid->id = ei->cache_valid_id;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 109) cid->nr_contig = hit->nr_contig;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 110) cid->fcluster = hit->fcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 111) cid->dcluster = hit->dcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 112) *cached_fclus = cid->fcluster + offset;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 113) *cached_dclus = cid->dcluster + offset;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 114) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 115) spin_unlock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 116)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 117) return offset;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 118) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 119)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 120) static struct exfat_cache *exfat_cache_merge(struct inode *inode,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 121) struct exfat_cache_id *new)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 122) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 123) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 124) struct exfat_cache *p;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 125)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 126) list_for_each_entry(p, &ei->cache_lru, cache_list) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 127) /* Find the same part as "new" in cluster-chain. */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 128) if (p->fcluster == new->fcluster) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 129) if (new->nr_contig > p->nr_contig)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 130) p->nr_contig = new->nr_contig;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 131) return p;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 132) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 133) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 134) return NULL;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 135) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 136)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 137) static void exfat_cache_add(struct inode *inode,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 138) struct exfat_cache_id *new)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 139) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 140) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 141) struct exfat_cache *cache, *tmp;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 142)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 143) if (new->fcluster == EXFAT_EOF_CLUSTER) /* dummy cache */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 144) return;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 145)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 146) spin_lock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 147) if (new->id != EXFAT_CACHE_VALID &&
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 148) new->id != ei->cache_valid_id)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 149) goto unlock; /* this cache was invalidated */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 150)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 151) cache = exfat_cache_merge(inode, new);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 152) if (cache == NULL) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 153) if (ei->nr_caches < EXFAT_MAX_CACHE) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 154) ei->nr_caches++;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 155) spin_unlock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 156)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 157) tmp = exfat_cache_alloc();
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 158) if (!tmp) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 159) spin_lock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 160) ei->nr_caches--;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 161) spin_unlock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 162) return;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 163) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 164)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 165) spin_lock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 166) cache = exfat_cache_merge(inode, new);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 167) if (cache != NULL) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 168) ei->nr_caches--;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 169) exfat_cache_free(tmp);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 170) goto out_update_lru;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 171) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 172) cache = tmp;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 173) } else {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 174) struct list_head *p = ei->cache_lru.prev;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 175)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 176) cache = list_entry(p,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 177) struct exfat_cache, cache_list);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 178) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 179) cache->fcluster = new->fcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 180) cache->dcluster = new->dcluster;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 181) cache->nr_contig = new->nr_contig;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 182) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 183) out_update_lru:
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 184) exfat_cache_update_lru(inode, cache);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 185) unlock:
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 186) spin_unlock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 187) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 188)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 189) /*
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 190) * Cache invalidation occurs rarely, thus the LRU chain is not updated. It
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 191) * fixes itself after a while.
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 192) */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 193) static void __exfat_cache_inval_inode(struct inode *inode)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 194) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 195) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 196) struct exfat_cache *cache;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 197)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 198) while (!list_empty(&ei->cache_lru)) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 199) cache = list_entry(ei->cache_lru.next,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 200) struct exfat_cache, cache_list);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 201) list_del_init(&cache->cache_list);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 202) ei->nr_caches--;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 203) exfat_cache_free(cache);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 204) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 205) /* Update. The copy of caches before this id is discarded. */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 206) ei->cache_valid_id++;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 207) if (ei->cache_valid_id == EXFAT_CACHE_VALID)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 208) ei->cache_valid_id++;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 209) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 210)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 211) void exfat_cache_inval_inode(struct inode *inode)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 212) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 213) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 214)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 215) spin_lock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 216) __exfat_cache_inval_inode(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 217) spin_unlock(&ei->cache_lru_lock);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 218) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 219)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 220) static inline int cache_contiguous(struct exfat_cache_id *cid,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 221) unsigned int dclus)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 222) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 223) cid->nr_contig++;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 224) return cid->dcluster + cid->nr_contig == dclus;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 225) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 226)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 227) static inline void cache_init(struct exfat_cache_id *cid,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 228) unsigned int fclus, unsigned int dclus)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 229) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 230) cid->id = EXFAT_CACHE_VALID;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 231) cid->fcluster = fclus;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 232) cid->dcluster = dclus;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 233) cid->nr_contig = 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 234) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 235)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 236) int exfat_get_cluster(struct inode *inode, unsigned int cluster,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 237) unsigned int *fclus, unsigned int *dclus,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 238) unsigned int *last_dclus, int allow_eof)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 239) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 240) struct super_block *sb = inode->i_sb;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 241) struct exfat_sb_info *sbi = EXFAT_SB(sb);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 242) unsigned int limit = sbi->num_clusters;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 243) struct exfat_inode_info *ei = EXFAT_I(inode);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 244) struct exfat_cache_id cid;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 245) unsigned int content;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 246)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 247) if (ei->start_clu == EXFAT_FREE_CLUSTER) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 248) exfat_fs_error(sb,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 249) "invalid access to exfat cache (entry 0x%08x)",
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 250) ei->start_clu);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 251) return -EIO;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 252) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 253)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 254) *fclus = 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 255) *dclus = ei->start_clu;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 256) *last_dclus = *dclus;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 257)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 258) /*
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 259) * Don`t use exfat_cache if zero offset or non-cluster allocation
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 260) */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 261) if (cluster == 0 || *dclus == EXFAT_EOF_CLUSTER)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 262) return 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 263)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 264) cache_init(&cid, EXFAT_EOF_CLUSTER, EXFAT_EOF_CLUSTER);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 265)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 266) if (exfat_cache_lookup(inode, cluster, &cid, fclus, dclus) ==
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 267) EXFAT_EOF_CLUSTER) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 268) /*
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 269) * dummy, always not contiguous
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 270) * This is reinitialized by cache_init(), later.
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 271) */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 272) WARN_ON(cid.id != EXFAT_CACHE_VALID ||
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 273) cid.fcluster != EXFAT_EOF_CLUSTER ||
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 274) cid.dcluster != EXFAT_EOF_CLUSTER ||
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 275) cid.nr_contig != 0);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 276) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 277)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 278) if (*fclus == cluster)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 279) return 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 280)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 281) while (*fclus < cluster) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 282) /* prevent the infinite loop of cluster chain */
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 283) if (*fclus > limit) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 284) exfat_fs_error(sb,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 285) "detected the cluster chain loop (i_pos %u)",
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 286) (*fclus));
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 287) return -EIO;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 288) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 289)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 290) if (exfat_ent_get(sb, *dclus, &content))
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 291) return -EIO;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 292)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 293) *last_dclus = *dclus;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 294) *dclus = content;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 295) (*fclus)++;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 296)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 297) if (content == EXFAT_EOF_CLUSTER) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 298) if (!allow_eof) {
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 299) exfat_fs_error(sb,
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 300) "invalid cluster chain (i_pos %u, last_clus 0x%08x is EOF)",
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 301) *fclus, (*last_dclus));
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 302) return -EIO;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 303) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 304)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 305) break;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 306) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 307)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 308) if (!cache_contiguous(&cid, *dclus))
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 309) cache_init(&cid, *fclus, *dclus);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 310) }
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 311)
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 312) exfat_cache_add(inode, &cid);
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 313) return 0;
c35b6810c4952 (Namjae Jeon 2020-03-02 15:21:39 +0900 314) }
VisionFive2 Linux kernel
StarFive Tech Linux Kernel for VisionFive (JH7110) boards (mirror)
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