d5c3428b2c
If the reply cache initialization fails due to a kmalloc failure, currently we try to soldier on with a reduced (or nonexistant) reply cache. Better to just fail immediately: the failure is then much easier to understand and debug, and it could save us complexity in some later code. (But actually, it doesn't help currently because the cache is also turned off in some odd failure cases; we should probably find a better way to handle those failure cases some day.) Fix some minor style problems while we're at it, and rename nfsd_cache_init() to remove the need for a comment describing it. Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
81 lines
1.6 KiB
C
81 lines
1.6 KiB
C
/*
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* include/linux/nfsd/cache.h
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*
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* Request reply cache. This was heavily inspired by the
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* implementation in 4.3BSD/4.4BSD.
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*
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* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
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*/
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#ifndef NFSCACHE_H
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#define NFSCACHE_H
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#ifdef __KERNEL__
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#include <linux/in.h>
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#include <linux/uio.h>
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/*
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* Representation of a reply cache entry. The first two members *must*
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* be hash_next and hash_prev.
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*/
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struct svc_cacherep {
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struct hlist_node c_hash;
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struct list_head c_lru;
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unsigned char c_state, /* unused, inprog, done */
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c_type, /* status, buffer */
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c_secure : 1; /* req came from port < 1024 */
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struct sockaddr_in c_addr;
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__be32 c_xid;
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u32 c_prot;
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u32 c_proc;
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u32 c_vers;
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unsigned long c_timestamp;
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union {
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struct kvec u_vec;
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__be32 u_status;
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} c_u;
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};
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#define c_replvec c_u.u_vec
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#define c_replstat c_u.u_status
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/* cache entry states */
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enum {
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RC_UNUSED,
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RC_INPROG,
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RC_DONE
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};
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/* return values */
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enum {
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RC_DROPIT,
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RC_REPLY,
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RC_DOIT,
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RC_INTR
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};
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/*
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* Cache types.
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* We may want to add more types one day, e.g. for diropres and
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* attrstat replies. Using cache entries with fixed length instead
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* of buffer pointers may be more efficient.
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*/
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enum {
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RC_NOCACHE,
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RC_REPLSTAT,
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RC_REPLBUFF,
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};
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/*
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* If requests are retransmitted within this interval, they're dropped.
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*/
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#define RC_DELAY (HZ/5)
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int nfsd_reply_cache_init(void);
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void nfsd_reply_cache_shutdown(void);
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int nfsd_cache_lookup(struct svc_rqst *, int);
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void nfsd_cache_update(struct svc_rqst *, int, __be32 *);
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#endif /* __KERNEL__ */
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#endif /* NFSCACHE_H */
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