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-rw-r--r--fs/nfsd/nfscache.c236
1 files changed, 115 insertions, 121 deletions
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index da52b594362a..26ad75ae2be0 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -9,6 +9,7 @@
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
+#include <linux/sunrpc/svc_xprt.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/sunrpc/addr.h>
@@ -35,48 +36,12 @@ struct nfsd_drc_bucket {
spinlock_t cache_lock;
};
-static struct nfsd_drc_bucket *drc_hashtbl;
-static struct kmem_cache *drc_slab;
-
-/* max number of entries allowed in the cache */
-static unsigned int max_drc_entries;
-
-/* number of significant bits in the hash value */
-static unsigned int maskbits;
-static unsigned int drc_hashsize;
-
-/*
- * Stats and other tracking of on the duplicate reply cache. All of these and
- * the "rc" fields in nfsdstats are protected by the cache_lock
- */
-
-/* total number of entries */
-static atomic_t num_drc_entries;
-
-/* cache misses due only to checksum comparison failures */
-static unsigned int payload_misses;
-
-/* amount of memory (in bytes) currently consumed by the DRC */
-static unsigned int drc_mem_usage;
-
-/* longest hash chain seen */
-static unsigned int longest_chain;
-
-/* size of cache when we saw the longest hash chain */
-static unsigned int longest_chain_cachesize;
-
static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
static unsigned long nfsd_reply_cache_count(struct shrinker *shrink,
struct shrink_control *sc);
static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink,
struct shrink_control *sc);
-static struct shrinker nfsd_reply_cache_shrinker = {
- .scan_objects = nfsd_reply_cache_scan,
- .count_objects = nfsd_reply_cache_count,
- .seeks = 1,
-};
-
/*
* Put a cap on the size of the DRC based on the amount of available
* low memory in the machine.
@@ -94,6 +59,9 @@ static struct shrinker nfsd_reply_cache_shrinker = {
* ...with a hard cap of 256k entries. In the worst case, each entry will be
* ~1k, so the above numbers should give a rough max of the amount of memory
* used in k.
+ *
+ * XXX: these limits are per-container, so memory used will increase
+ * linearly with number of containers. Maybe that's OK.
*/
static unsigned int
nfsd_cache_size_limit(void)
@@ -116,17 +84,18 @@ nfsd_hashsize(unsigned int limit)
}
static u32
-nfsd_cache_hash(__be32 xid)
+nfsd_cache_hash(__be32 xid, struct nfsd_net *nn)
{
- return hash_32(be32_to_cpu(xid), maskbits);
+ return hash_32(be32_to_cpu(xid), nn->maskbits);
}
static struct svc_cacherep *
-nfsd_reply_cache_alloc(struct svc_rqst *rqstp, __wsum csum)
+nfsd_reply_cache_alloc(struct svc_rqst *rqstp, __wsum csum,
+ struct nfsd_net *nn)
{
struct svc_cacherep *rp;
- rp = kmem_cache_alloc(drc_slab, GFP_KERNEL);
+ rp = kmem_cache_alloc(nn->drc_slab, GFP_KERNEL);
if (rp) {
rp->c_state = RC_UNUSED;
rp->c_type = RC_NOCACHE;
@@ -147,91 +116,101 @@ nfsd_reply_cache_alloc(struct svc_rqst *rqstp, __wsum csum)
}
static void
-nfsd_reply_cache_free_locked(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
+nfsd_reply_cache_free_locked(struct nfsd_drc_bucket *b, struct svc_cacherep *rp,
+ struct nfsd_net *nn)
{
if (rp->c_type == RC_REPLBUFF && rp->c_replvec.iov_base) {
- drc_mem_usage -= rp->c_replvec.iov_len;
+ nn->drc_mem_usage -= rp->c_replvec.iov_len;
kfree(rp->c_replvec.iov_base);
}
if (rp->c_state != RC_UNUSED) {
rb_erase(&rp->c_node, &b->rb_head);
list_del(&rp->c_lru);
- atomic_dec(&num_drc_entries);
- drc_mem_usage -= sizeof(*rp);
+ atomic_dec(&nn->num_drc_entries);
+ nn->drc_mem_usage -= sizeof(*rp);
}
- kmem_cache_free(drc_slab, rp);
+ kmem_cache_free(nn->drc_slab, rp);
}
static void
-nfsd_reply_cache_free(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
+nfsd_reply_cache_free(struct nfsd_drc_bucket *b, struct svc_cacherep *rp,
+ struct nfsd_net *nn)
{
spin_lock(&b->cache_lock);
- nfsd_reply_cache_free_locked(b, rp);
+ nfsd_reply_cache_free_locked(b, rp, nn);
spin_unlock(&b->cache_lock);
}
-int nfsd_reply_cache_init(void)
+int nfsd_reply_cache_init(struct nfsd_net *nn)
{
unsigned int hashsize;
unsigned int i;
int status = 0;
- max_drc_entries = nfsd_cache_size_limit();
- atomic_set(&num_drc_entries, 0);
- hashsize = nfsd_hashsize(max_drc_entries);
- maskbits = ilog2(hashsize);
+ nn->max_drc_entries = nfsd_cache_size_limit();
+ atomic_set(&nn->num_drc_entries, 0);
+ hashsize = nfsd_hashsize(nn->max_drc_entries);
+ nn->maskbits = ilog2(hashsize);
- status = register_shrinker(&nfsd_reply_cache_shrinker);
+ nn->nfsd_reply_cache_shrinker.scan_objects = nfsd_reply_cache_scan;
+ nn->nfsd_reply_cache_shrinker.count_objects = nfsd_reply_cache_count;
+ nn->nfsd_reply_cache_shrinker.seeks = 1;
+ status = register_shrinker(&nn->nfsd_reply_cache_shrinker);
if (status)
- return status;
-
- drc_slab = kmem_cache_create("nfsd_drc", sizeof(struct svc_cacherep),
- 0, 0, NULL);
- if (!drc_slab)
goto out_nomem;
- drc_hashtbl = kcalloc(hashsize, sizeof(*drc_hashtbl), GFP_KERNEL);
- if (!drc_hashtbl) {
- drc_hashtbl = vzalloc(array_size(hashsize,
- sizeof(*drc_hashtbl)));
- if (!drc_hashtbl)
- goto out_nomem;
+ nn->drc_slab = kmem_cache_create("nfsd_drc",
+ sizeof(struct svc_cacherep), 0, 0, NULL);
+ if (!nn->drc_slab)
+ goto out_shrinker;
+
+ nn->drc_hashtbl = kcalloc(hashsize,
+ sizeof(*nn->drc_hashtbl), GFP_KERNEL);
+ if (!nn->drc_hashtbl) {
+ nn->drc_hashtbl = vzalloc(array_size(hashsize,
+ sizeof(*nn->drc_hashtbl)));
+ if (!nn->drc_hashtbl)
+ goto out_slab;
}
for (i = 0; i < hashsize; i++) {
- INIT_LIST_HEAD(&drc_hashtbl[i].lru_head);
- spin_lock_init(&drc_hashtbl[i].cache_lock);
+ INIT_LIST_HEAD(&nn->drc_hashtbl[i].lru_head);
+ spin_lock_init(&nn->drc_hashtbl[i].cache_lock);
}
- drc_hashsize = hashsize;
+ nn->drc_hashsize = hashsize;
return 0;
+out_slab:
+ kmem_cache_destroy(nn->drc_slab);
+out_shrinker:
+ unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
out_nomem:
printk(KERN_ERR "nfsd: failed to allocate reply cache\n");
- nfsd_reply_cache_shutdown();
return -ENOMEM;
}
-void nfsd_reply_cache_shutdown(void)
+void nfsd_reply_cache_shutdown(struct nfsd_net *nn)
{
struct svc_cacherep *rp;
unsigned int i;
- unregister_shrinker(&nfsd_reply_cache_shrinker);
+ unregister_shrinker(&nn->nfsd_reply_cache_shrinker);
- for (i = 0; i < drc_hashsize; i++) {
- struct list_head *head = &drc_hashtbl[i].lru_head;
+ for (i = 0; i < nn->drc_hashsize; i++) {
+ struct list_head *head = &nn->drc_hashtbl[i].lru_head;
while (!list_empty(head)) {
rp = list_first_entry(head, struct svc_cacherep, c_lru);
- nfsd_reply_cache_free_locked(&drc_hashtbl[i], rp);
+ nfsd_reply_cache_free_locked(&nn->drc_hashtbl[i],
+ rp, nn);
}
}
- kvfree(drc_hashtbl);
- drc_hashtbl = NULL;
- drc_hashsize = 0;
+ kvfree(nn->drc_hashtbl);
+ nn->drc_hashtbl = NULL;
+ nn->drc_hashsize = 0;
- kmem_cache_destroy(drc_slab);
- drc_slab = NULL;
+ kmem_cache_destroy(nn->drc_slab);
+ nn->drc_slab = NULL;
}
/*
@@ -246,7 +225,7 @@ lru_put_end(struct nfsd_drc_bucket *b, struct svc_cacherep *rp)
}
static long
-prune_bucket(struct nfsd_drc_bucket *b)
+prune_bucket(struct nfsd_drc_bucket *b, struct nfsd_net *nn)
{
struct svc_cacherep *rp, *tmp;
long freed = 0;
@@ -258,10 +237,10 @@ prune_bucket(struct nfsd_drc_bucket *b)
*/
if (rp->c_state == RC_INPROG)
continue;
- if (atomic_read(&num_drc_entries) <= max_drc_entries &&
+ if (atomic_read(&nn->num_drc_entries) <= nn->max_drc_entries &&
time_before(jiffies, rp->c_timestamp + RC_EXPIRE))
break;
- nfsd_reply_cache_free_locked(b, rp);
+ nfsd_reply_cache_free_locked(b, rp, nn);
freed++;
}
return freed;
@@ -272,18 +251,18 @@ prune_bucket(struct nfsd_drc_bucket *b)
* Also prune the oldest ones when the total exceeds the max number of entries.
*/
static long
-prune_cache_entries(void)
+prune_cache_entries(struct nfsd_net *nn)
{
unsigned int i;
long freed = 0;
- for (i = 0; i < drc_hashsize; i++) {
- struct nfsd_drc_bucket *b = &drc_hashtbl[i];
+ for (i = 0; i < nn->drc_hashsize; i++) {
+ struct nfsd_drc_bucket *b = &nn->drc_hashtbl[i];
if (list_empty(&b->lru_head))
continue;
spin_lock(&b->cache_lock);
- freed += prune_bucket(b);
+ freed += prune_bucket(b, nn);
spin_unlock(&b->cache_lock);
}
return freed;
@@ -292,13 +271,19 @@ prune_cache_entries(void)
static unsigned long
nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
{
- return atomic_read(&num_drc_entries);
+ struct nfsd_net *nn = container_of(shrink,
+ struct nfsd_net, nfsd_reply_cache_shrinker);
+
+ return atomic_read(&nn->num_drc_entries);
}
static unsigned long
nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
{
- return prune_cache_entries();
+ struct nfsd_net *nn = container_of(shrink,
+ struct nfsd_net, nfsd_reply_cache_shrinker);
+
+ return prune_cache_entries(nn);
}
/*
* Walk an xdr_buf and get a CRC for at most the first RC_CSUMLEN bytes
@@ -334,11 +319,12 @@ nfsd_cache_csum(struct svc_rqst *rqstp)
}
static int
-nfsd_cache_key_cmp(const struct svc_cacherep *key, const struct svc_cacherep *rp)
+nfsd_cache_key_cmp(const struct svc_cacherep *key,
+ const struct svc_cacherep *rp, struct nfsd_net *nn)
{
if (key->c_key.k_xid == rp->c_key.k_xid &&
key->c_key.k_csum != rp->c_key.k_csum)
- ++payload_misses;
+ ++nn->payload_misses;
return memcmp(&key->c_key, &rp->c_key, sizeof(key->c_key));
}
@@ -349,7 +335,8 @@ nfsd_cache_key_cmp(const struct svc_cacherep *key, const struct svc_cacherep *rp
* inserts an empty key on failure.
*/
static struct svc_cacherep *
-nfsd_cache_insert(struct nfsd_drc_bucket *b, struct svc_cacherep *key)
+nfsd_cache_insert(struct nfsd_drc_bucket *b, struct svc_cacherep *key,
+ struct nfsd_net *nn)
{
struct svc_cacherep *rp, *ret = key;
struct rb_node **p = &b->rb_head.rb_node,
@@ -362,7 +349,7 @@ nfsd_cache_insert(struct nfsd_drc_bucket *b, struct svc_cacherep *key)
parent = *p;
rp = rb_entry(parent, struct svc_cacherep, c_node);
- cmp = nfsd_cache_key_cmp(key, rp);
+ cmp = nfsd_cache_key_cmp(key, rp, nn);
if (cmp < 0)
p = &parent->rb_left;
else if (cmp > 0)
@@ -376,14 +363,14 @@ nfsd_cache_insert(struct nfsd_drc_bucket *b, struct svc_cacherep *key)
rb_insert_color(&key->c_node, &b->rb_head);
out:
/* tally hash chain length stats */
- if (entries > longest_chain) {
- longest_chain = entries;
- longest_chain_cachesize = atomic_read(&num_drc_entries);
- } else if (entries == longest_chain) {
+ if (entries > nn->longest_chain) {
+ nn->longest_chain = entries;
+ nn->longest_chain_cachesize = atomic_read(&nn->num_drc_entries);
+ } else if (entries == nn->longest_chain) {
/* prefer to keep the smallest cachesize possible here */
- longest_chain_cachesize = min_t(unsigned int,
- longest_chain_cachesize,
- atomic_read(&num_drc_entries));
+ nn->longest_chain_cachesize = min_t(unsigned int,
+ nn->longest_chain_cachesize,
+ atomic_read(&nn->num_drc_entries));
}
lru_put_end(b, ret);
@@ -400,11 +387,12 @@ out:
int
nfsd_cache_lookup(struct svc_rqst *rqstp)
{
+ struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
struct svc_cacherep *rp, *found;
__be32 xid = rqstp->rq_xid;
__wsum csum;
- u32 hash = nfsd_cache_hash(xid);
- struct nfsd_drc_bucket *b = &drc_hashtbl[hash];
+ u32 hash = nfsd_cache_hash(xid, nn);
+ struct nfsd_drc_bucket *b = &nn->drc_hashtbl[hash];
int type = rqstp->rq_cachetype;
int rtn = RC_DOIT;
@@ -420,16 +408,16 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
* Since the common case is a cache miss followed by an insert,
* preallocate an entry.
*/
- rp = nfsd_reply_cache_alloc(rqstp, csum);
+ rp = nfsd_reply_cache_alloc(rqstp, csum, nn);
if (!rp) {
dprintk("nfsd: unable to allocate DRC entry!\n");
return rtn;
}
spin_lock(&b->cache_lock);
- found = nfsd_cache_insert(b, rp);
+ found = nfsd_cache_insert(b, rp, nn);
if (found != rp) {
- nfsd_reply_cache_free_locked(NULL, rp);
+ nfsd_reply_cache_free_locked(NULL, rp, nn);
rp = found;
goto found_entry;
}
@@ -438,11 +426,11 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
rqstp->rq_cacherep = rp;
rp->c_state = RC_INPROG;
- atomic_inc(&num_drc_entries);
- drc_mem_usage += sizeof(*rp);
+ atomic_inc(&nn->num_drc_entries);
+ nn->drc_mem_usage += sizeof(*rp);
/* go ahead and prune the cache */
- prune_bucket(b);
+ prune_bucket(b, nn);
out:
spin_unlock(&b->cache_lock);
return rtn;
@@ -477,7 +465,7 @@ found_entry:
break;
default:
printk(KERN_WARNING "nfsd: bad repcache type %d\n", rp->c_type);
- nfsd_reply_cache_free_locked(b, rp);
+ nfsd_reply_cache_free_locked(b, rp, nn);
}
goto out;
@@ -502,6 +490,7 @@ found_entry:
void
nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
{
+ struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
struct svc_cacherep *rp = rqstp->rq_cacherep;
struct kvec *resv = &rqstp->rq_res.head[0], *cachv;
u32 hash;
@@ -512,15 +501,15 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
if (!rp)
return;
- hash = nfsd_cache_hash(rp->c_key.k_xid);
- b = &drc_hashtbl[hash];
+ hash = nfsd_cache_hash(rp->c_key.k_xid, nn);
+ b = &nn->drc_hashtbl[hash];
len = resv->iov_len - ((char*)statp - (char*)resv->iov_base);
len >>= 2;
/* Don't cache excessive amounts of data and XDR failures */
if (!statp || len > (256 >> 2)) {
- nfsd_reply_cache_free(b, rp);
+ nfsd_reply_cache_free(b, rp, nn);
return;
}
@@ -535,18 +524,18 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
bufsize = len << 2;
cachv->iov_base = kmalloc(bufsize, GFP_KERNEL);
if (!cachv->iov_base) {
- nfsd_reply_cache_free(b, rp);
+ nfsd_reply_cache_free(b, rp, nn);
return;
}
cachv->iov_len = bufsize;
memcpy(cachv->iov_base, statp, bufsize);
break;
case RC_NOCACHE:
- nfsd_reply_cache_free(b, rp);
+ nfsd_reply_cache_free(b, rp, nn);
return;
}
spin_lock(&b->cache_lock);
- drc_mem_usage += bufsize;
+ nn->drc_mem_usage += bufsize;
lru_put_end(b, rp);
rp->c_secure = test_bit(RQ_SECURE, &rqstp->rq_flags);
rp->c_type = cachetype;
@@ -582,21 +571,26 @@ nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *data)
*/
static int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
{
- seq_printf(m, "max entries: %u\n", max_drc_entries);
+ struct nfsd_net *nn = v;
+
+ seq_printf(m, "max entries: %u\n", nn->max_drc_entries);
seq_printf(m, "num entries: %u\n",
- atomic_read(&num_drc_entries));
- seq_printf(m, "hash buckets: %u\n", 1 << maskbits);
- seq_printf(m, "mem usage: %u\n", drc_mem_usage);
+ atomic_read(&nn->num_drc_entries));
+ seq_printf(m, "hash buckets: %u\n", 1 << nn->maskbits);
+ seq_printf(m, "mem usage: %u\n", nn->drc_mem_usage);
seq_printf(m, "cache hits: %u\n", nfsdstats.rchits);
seq_printf(m, "cache misses: %u\n", nfsdstats.rcmisses);
seq_printf(m, "not cached: %u\n", nfsdstats.rcnocache);
- seq_printf(m, "payload misses: %u\n", payload_misses);
- seq_printf(m, "longest chain len: %u\n", longest_chain);
- seq_printf(m, "cachesize at longest: %u\n", longest_chain_cachesize);
+ seq_printf(m, "payload misses: %u\n", nn->payload_misses);
+ seq_printf(m, "longest chain len: %u\n", nn->longest_chain);
+ seq_printf(m, "cachesize at longest: %u\n", nn->longest_chain_cachesize);
return 0;
}
int nfsd_reply_cache_stats_open(struct inode *inode, struct file *file)
{
- return single_open(file, nfsd_reply_cache_stats_show, NULL);
+ struct nfsd_net *nn = net_generic(file_inode(file)->i_sb->s_fs_info,
+ nfsd_net_id);
+
+ return single_open(file, nfsd_reply_cache_stats_show, nn);
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.