diff options
Diffstat (limited to 'fs/nfsd/nfscache.c')
-rw-r--r-- | fs/nfsd/nfscache.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index 5bfc2ac60d54..6f0aa4989c61 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c | |||
@@ -29,15 +29,24 @@ | |||
29 | */ | 29 | */ |
30 | #define CACHESIZE 1024 | 30 | #define CACHESIZE 1024 |
31 | #define HASHSIZE 64 | 31 | #define HASHSIZE 64 |
32 | #define REQHASH(xid) (((((__force __u32)xid) >> 24) ^ ((__force __u32)xid)) & (HASHSIZE-1)) | ||
33 | 32 | ||
34 | static struct hlist_head * hash_list; | 33 | static struct hlist_head * cache_hash; |
35 | static struct list_head lru_head; | 34 | static struct list_head lru_head; |
36 | static int cache_disabled = 1; | 35 | static int cache_disabled = 1; |
37 | 36 | ||
37 | /* | ||
38 | * Calculate the hash index from an XID. | ||
39 | */ | ||
40 | static inline u32 request_hash(u32 xid) | ||
41 | { | ||
42 | u32 h = xid; | ||
43 | h ^= (xid >> 24); | ||
44 | return h & (HASHSIZE-1); | ||
45 | } | ||
46 | |||
38 | static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec); | 47 | static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec); |
39 | 48 | ||
40 | /* | 49 | /* |
41 | * locking for the reply cache: | 50 | * locking for the reply cache: |
42 | * A cache entry is "single use" if c_state == RC_INPROG | 51 | * A cache entry is "single use" if c_state == RC_INPROG |
43 | * Otherwise, it when accessing _prev or _next, the lock must be held. | 52 | * Otherwise, it when accessing _prev or _next, the lock must be held. |
@@ -62,8 +71,8 @@ int nfsd_reply_cache_init(void) | |||
62 | i--; | 71 | i--; |
63 | } | 72 | } |
64 | 73 | ||
65 | hash_list = kcalloc (HASHSIZE, sizeof(struct hlist_head), GFP_KERNEL); | 74 | cache_hash = kcalloc (HASHSIZE, sizeof(struct hlist_head), GFP_KERNEL); |
66 | if (!hash_list) | 75 | if (!cache_hash) |
67 | goto out_nomem; | 76 | goto out_nomem; |
68 | 77 | ||
69 | cache_disabled = 0; | 78 | cache_disabled = 0; |
@@ -88,8 +97,8 @@ void nfsd_reply_cache_shutdown(void) | |||
88 | 97 | ||
89 | cache_disabled = 1; | 98 | cache_disabled = 1; |
90 | 99 | ||
91 | kfree (hash_list); | 100 | kfree (cache_hash); |
92 | hash_list = NULL; | 101 | cache_hash = NULL; |
93 | } | 102 | } |
94 | 103 | ||
95 | /* | 104 | /* |
@@ -108,7 +117,7 @@ static void | |||
108 | hash_refile(struct svc_cacherep *rp) | 117 | hash_refile(struct svc_cacherep *rp) |
109 | { | 118 | { |
110 | hlist_del_init(&rp->c_hash); | 119 | hlist_del_init(&rp->c_hash); |
111 | hlist_add_head(&rp->c_hash, hash_list + REQHASH(rp->c_xid)); | 120 | hlist_add_head(&rp->c_hash, cache_hash + request_hash(rp->c_xid)); |
112 | } | 121 | } |
113 | 122 | ||
114 | /* | 123 | /* |
@@ -138,7 +147,7 @@ nfsd_cache_lookup(struct svc_rqst *rqstp, int type) | |||
138 | spin_lock(&cache_lock); | 147 | spin_lock(&cache_lock); |
139 | rtn = RC_DOIT; | 148 | rtn = RC_DOIT; |
140 | 149 | ||
141 | rh = &hash_list[REQHASH(xid)]; | 150 | rh = &cache_hash[request_hash(xid)]; |
142 | hlist_for_each_entry(rp, hn, rh, c_hash) { | 151 | hlist_for_each_entry(rp, hn, rh, c_hash) { |
143 | if (rp->c_state != RC_UNUSED && | 152 | if (rp->c_state != RC_UNUSED && |
144 | xid == rp->c_xid && proc == rp->c_proc && | 153 | xid == rp->c_xid && proc == rp->c_proc && |
@@ -264,7 +273,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp) | |||
264 | 273 | ||
265 | len = resv->iov_len - ((char*)statp - (char*)resv->iov_base); | 274 | len = resv->iov_len - ((char*)statp - (char*)resv->iov_base); |
266 | len >>= 2; | 275 | len >>= 2; |
267 | 276 | ||
268 | /* Don't cache excessive amounts of data and XDR failures */ | 277 | /* Don't cache excessive amounts of data and XDR failures */ |
269 | if (!statp || len > (256 >> 2)) { | 278 | if (!statp || len > (256 >> 2)) { |
270 | rp->c_state = RC_UNUSED; | 279 | rp->c_state = RC_UNUSED; |