/*
- * linux/fs/nfsd/nfscache.c
- *
* Request reply cache. This is currently a global cache, but this may
* change in the future and be a per-client cache.
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
-#include <linux/kernel.h>
-#include <linux/time.h>
#include <linux/slab.h>
-#include <linux/string.h>
-#include <linux/spinlock.h>
-#include <linux/list.h>
-#include <linux/sunrpc/svc.h>
-#include <linux/nfsd/nfsd.h>
-#include <linux/nfsd/cache.h>
+#include "nfsd.h"
+#include "cache.h"
/* Size of reply cache. Common values are:
* 4.3BSD: 128
*/
#define CACHESIZE 1024
#define HASHSIZE 64
-#define REQHASH(xid) (((((__force __u32)xid) >> 24) ^ ((__force __u32)xid)) & (HASHSIZE-1))
-static struct hlist_head * hash_list;
+static struct hlist_head * cache_hash;
static struct list_head lru_head;
static int cache_disabled = 1;
+/*
+ * Calculate the hash index from an XID.
+ */
+static inline u32 request_hash(u32 xid)
+{
+ u32 h = xid;
+ h ^= (xid >> 24);
+ return h & (HASHSIZE-1);
+}
+
static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
-/*
+/*
* locking for the reply cache:
* A cache entry is "single use" if c_state == RC_INPROG
* Otherwise, it when accessing _prev or _next, the lock must be held.
*/
static DEFINE_SPINLOCK(cache_lock);
-void
-nfsd_cache_init(void)
+int nfsd_reply_cache_init(void)
{
struct svc_cacherep *rp;
int i;
INIT_LIST_HEAD(&lru_head);
i = CACHESIZE;
- while(i) {
+ while (i) {
rp = kmalloc(sizeof(*rp), GFP_KERNEL);
- if (!rp) break;
+ if (!rp)
+ goto out_nomem;
list_add(&rp->c_lru, &lru_head);
rp->c_state = RC_UNUSED;
rp->c_type = RC_NOCACHE;
i--;
}
- if (i)
- printk (KERN_ERR "nfsd: cannot allocate all %d cache entries, only got %d\n",
- CACHESIZE, CACHESIZE-i);
-
- hash_list = kcalloc (HASHSIZE, sizeof(struct hlist_head), GFP_KERNEL);
- if (!hash_list) {
- nfsd_cache_shutdown();
- printk (KERN_ERR "nfsd: cannot allocate %Zd bytes for hash list\n",
- HASHSIZE * sizeof(struct hlist_head));
- return;
- }
+ cache_hash = kcalloc (HASHSIZE, sizeof(struct hlist_head), GFP_KERNEL);
+ if (!cache_hash)
+ goto out_nomem;
cache_disabled = 0;
+ return 0;
+out_nomem:
+ printk(KERN_ERR "nfsd: failed to allocate reply cache\n");
+ nfsd_reply_cache_shutdown();
+ return -ENOMEM;
}
-void
-nfsd_cache_shutdown(void)
+void nfsd_reply_cache_shutdown(void)
{
struct svc_cacherep *rp;
cache_disabled = 1;
- kfree (hash_list);
- hash_list = NULL;
+ kfree (cache_hash);
+ cache_hash = NULL;
}
/*
hash_refile(struct svc_cacherep *rp)
{
hlist_del_init(&rp->c_hash);
- hlist_add_head(&rp->c_hash, hash_list + REQHASH(rp->c_xid));
+ hlist_add_head(&rp->c_hash, cache_hash + request_hash(rp->c_xid));
}
/*
spin_lock(&cache_lock);
rtn = RC_DOIT;
- rh = &hash_list[REQHASH(xid)];
+ rh = &cache_hash[request_hash(xid)];
hlist_for_each_entry(rp, hn, rh, c_hash) {
if (rp->c_state != RC_UNUSED &&
xid == rp->c_xid && proc == rp->c_proc &&
}
}
- /* This should not happen */
- if (rp == NULL) {
+ /* All entries on the LRU are in-progress. This should not happen */
+ if (&rp->c_lru == &lru_head) {
static int complaints;
printk(KERN_WARNING "nfsd: all repcache entries locked!\n");
rp->c_state = RC_INPROG;
rp->c_xid = xid;
rp->c_proc = proc;
- rp->c_addr = rqstp->rq_addr;
+ memcpy(&rp->c_addr, svc_addr_in(rqstp), sizeof(rp->c_addr));
rp->c_prot = proto;
rp->c_vers = vers;
rp->c_timestamp = jiffies;
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)) {
rp->c_state = RC_UNUSED;