diff options
Diffstat (limited to 'fs/coda/namecache.c')
| -rw-r--r-- | fs/coda/namecache.c | 832 |
1 files changed, 0 insertions, 832 deletions
diff --git a/fs/coda/namecache.c b/fs/coda/namecache.c deleted file mode 100644 index 08f1ee9e7..000000000 --- a/fs/coda/namecache.c +++ /dev/null @@ -1,832 +0,0 @@ -/* - * Cache operations for Coda. - * Original version: (C) 1996 Peter Braam - * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University - * - * Carnegie Mellon encourages users of this code to contribute improvements - * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>. - */ - -/* - * This module contains the routines to implement the CFS name cache. The - * purpose of this cache is to reduce the cost of translating pathnames - * into Vice FIDs. Each entry in the cache contains the name of the file, - * the vnode (FID) of the parent directory, and the cred structure of the - * user accessing the file. - * - * The first time a file is accessed, it is looked up by the local Venus - * which first insures that the user has access to the file. In addition - * we are guaranteed that Venus will invalidate any name cache entries in - * case the user no longer should be able to access the file. For these - * reasons we do not need to keep access list information as well as a - * cred structure for each entry. - * - * The table can be accessed through the routines cnc_init(), cnc_enter(), - * cnc_lookup(), cnc_rmfidcred(), cnc_rmfid(), cnc_rmcred(), and cnc_purge(). - * There are several other routines which aid in the implementation of the - * hash table. - */ - -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/fs.h> -#include <linux/stat.h> -#include <linux/errno.h> -#include <linux/locks.h> -#include <asm/segment.h> -#include <linux/string.h> - -#include <linux/coda.h> -#include <linux/coda_linux.h> -#include <linux/coda_cnode.h> -#include <linux/coda_namecache.h> - -int cfsnc_use; - -static struct cfscache * cfsnc_find(struct cnode *dcp, const char * name, int namelen, int hash); -static void cfsnc_remove(struct cfscache *cncp); -static inline int nchash(const char *, int, struct cnode *); -static inline int ncmatch(struct cfscache *, const char *, int, - struct cnode *); -static inline void hashins(struct cfscache *a, struct cfscache *pred); -static inline void hashrem(struct cfscache *a); -static inline void hashnull(struct cfscache *); -static inline void lrurem(struct cfscache *a); -static inline void lruins(struct cfscache *a, struct cfscache *pred); -static void cfsnc_gather_stats(void); - - -/* externals */ -extern int coda_fideq(ViceFid *fid1, ViceFid *fid2); -extern int coda_debug; -extern int coda_print_entry; -extern struct super_block *coda_super_block; - - - -/* - * Declaration of the name cache data structure. - */ - -int cfsnc_use = 0; /* Indicate use of CFS Name Cache */ -int cfsnc_size = CFSNC_CACHESIZE; /* size of the cache */ -int cfsnc_hashsize = CFSNC_HASHSIZE; /* size of the primary hash */ -int cfsnc_flushme = 0; -int cfsnc_procsize = 0; -static int cfsnc_force = 0; - -struct cfshash { - struct cfscache *hash_next, *hash_prev; - int length; -}; - -struct cfslruhead { - struct cfscache *dummy1, *dummy2; - struct cfscache *lru_next, *lru_prev; -}; - -struct cfscache *cfsncheap; /* pointer to the cache entries */ -struct cfshash *cfsnchash; /* hash table of cfscache pointers */ -struct cfslruhead cfsnc_lru; /* head of lru chain; prev = lru */ - -struct cfsnc_statistics cfsnc_stat; /* Keep various stats */ - -#define TOTAL_CACHE_SIZE (sizeof(struct cfscache) * cfsnc_size) -#define TOTAL_HASH_SIZE (sizeof(struct cfshash) * cfsnc_hashsize) -int cfsnc_initialized = 0; /* Initially the cache has not been initialized */ - -/* - * for testing purposes - */ -int cfsnc_debug = 1; - - -/* - * Auxillary routines -- shouldn't be entry points - */ - - -/* - * Hash function for the primary hash. - * First try -- (first + last letters + length + (int)cp) mod size - * 2nd try -- same, except dir fid.vnode instead of cp - */ -static inline int -nchash(const char *name, int namelen, struct cnode *cp) -{ - return ((name[0] + name[namelen-1] + - namelen + (int)(cp)) & (cfsnc_hashsize-1)); -} - -/* matching function */ -static inline int ncmatch(struct cfscache *cp, const char *name, int namelen, - struct cnode *dcp) -{ - return ((namelen == cp->namelen) && (dcp == cp->dcp) && - (memcmp(cp->name,name,namelen) == 0)); -} - -/* insert a behind pred */ -static inline void hashins(struct cfscache *a, struct cfscache *pred) -{ - a->hash_next = pred->hash_next; - pred->hash_next->hash_prev= a; - pred->hash_next = a; - a->hash_prev = pred; -} - -static inline void hashrem(struct cfscache *a) -{ - a->hash_prev->hash_next = a->hash_next; - a->hash_next->hash_prev = a->hash_prev; -} - -static inline void hashnull(struct cfscache *elem) { - elem->hash_next = elem; - elem->hash_prev = elem; -} - -static inline void lrurem(struct cfscache *a) -{ - a->lru_prev->lru_next = a->lru_next; - a->lru_next->lru_prev = a->lru_prev; -} - -static inline void lruins(struct cfscache *a, struct cfscache *pred) -{ - pred->lru_next->lru_prev= a; - a->lru_next = pred->lru_next; - - a->lru_prev = pred; - pred->lru_next = a; -} - -static struct cfscache * -cfsnc_find(struct cnode *dcp, const char * name, int namelen, int hash) -{ - /* - * hash to find the appropriate bucket, look through the chain - * for the right entry - */ - register struct cfscache *cncp; - int count = 1; - - CDEBUG(D_CACHE, "dcp 0x%x, name %s, len %d, hash %d\n", - (int)dcp, name, namelen, hash); - - for (cncp = cfsnchash[hash].hash_next; - cncp != (struct cfscache *)&cfsnchash[hash]; - cncp = cncp->hash_next, count++) - { - - if (ncmatch(cncp, name, namelen, dcp)) - { - cfsnc_stat.Search_len += count; - CDEBUG(D_CACHE, "dcp 0x%x,found.\n", (int) dcp); - return(cncp); - - } - } - CDEBUG(D_CACHE, "dcp 0x%x,not found.\n", (int) dcp); - return((struct cfscache *)0); -} - -static void -cfsnc_remove(struct cfscache *cncp) -{ - /* - * remove an entry -- VN_RELE(cncp->dcp, cp), crfree(cred), - * remove it from it's hash chain, and - * place it at the head of the lru list. - */ - CDEBUG(D_CACHE, "remove %s from parent %lx.%lx.%lx\n", - cncp->name, (cncp->dcp)->c_fid.Volume, - (cncp->dcp)->c_fid.Vnode, (cncp->dcp)->c_fid.Unique); - - hashrem(cncp); - hashnull(cncp); /* have it be a null chain */ - - /* VN_RELE(CTOV(cncp->dcp)); */ - iput(CTOI(cncp->cp)); - /* crfree(cncp->cred); */ - - memset(DATA_PART(cncp), 0 ,DATA_SIZE); - cncp->cp = NULL; - cncp->dcp = (struct cnode *) 0; - - /* Put the null entry just after the least-recently-used entry */ - lrurem(cncp); - lruins(cncp, cfsnc_lru.lru_prev); -} - - -/* - * Entry points for the CFS Name Cache - */ - -/* - * Initialize the cache, the LRU structure and the Hash structure(s) - */ -void -cfsnc_init(void) -{ - register int i; - - /* zero the statistics structure */ - cfsnc_procsize = 10000 * cfsnc_hashsize + cfsnc_size; - memset(&cfsnc_stat, 0, (sizeof(struct cfsnc_statistics))); - - CODA_ALLOC(cfsncheap, struct cfscache *, TOTAL_CACHE_SIZE); - CODA_ALLOC(cfsnchash, struct cfshash *, TOTAL_HASH_SIZE); - - cfsnc_lru.lru_next = cfsnc_lru.lru_prev = (struct cfscache *)&cfsnc_lru; - - /* initialize the heap */ - for (i=0; i < cfsnc_size; i++) { - lruins(&cfsncheap[i], (struct cfscache *) &cfsnc_lru); - hashnull(&cfsncheap[i]); - cfsncheap[i].cp = cfsncheap[i].dcp = (struct cnode *)0; - } - - for (i=0; i < cfsnc_hashsize; i++) { /* initialize the hashtable */ - hashnull((struct cfscache *)&cfsnchash[i]); - cfsnchash[i].length=0; /* bucket length */ - } - - cfsnc_initialized = 1; - CDEBUG(D_CACHE, "cfsnc_initialized is now 1.\n"); -} - -/* - * Enter a new (dir cnode, name) pair into the cache, updating the - * LRU and Hash as needed. - */ - -void -cfsnc_enter(struct cnode *dcp, register const char *name, int namelen, struct cnode *cp) -{ - register struct cfscache *cncp; - register int hash; - - if (cfsnc_use == 0) /* Cache is off */ - return; - - CDEBUG(D_CACHE, "dcp 0x%x cp 0x%x name %s, ind 0x%x \n", - (int)dcp, (int)cp, name, (int)cp->c_vnode); - - if (namelen > CFSNC_NAMELEN) { - CDEBUG(D_CACHE, "long name enter %s\n",name); - cfsnc_stat.long_name_enters++; /* record stats */ - return; - } - - hash = nchash(name, namelen, dcp); - CDEBUG(D_CACHE, "Calling find with name %s, dcp %d, hash %d\n", - name, (int) dcp, (int) hash); - - cncp = cfsnc_find(dcp, name, namelen, hash); - if (cncp != (struct cfscache *) 0) { - printk("cfsnc_enter: Duplicate cache entry; tell Peter.\n"); - cfsnc_stat.dbl_enters++; /* duplicate entry */ - return; - } - - cfsnc_stat.enters++; /* record the enters statistic */ - - /* Grab the lru element in the lru chain */ - cncp = cfsnc_lru.lru_prev; - - lrurem(cncp); /* remove it from the lists */ - - /* if cncp is on hash list remove it */ - if ( cncp->dcp != (struct cnode *) 0 ) { - /* We have to decrement the appropriate hash bucket length - here, so we have to find the hash bucket */ - cfsnchash[nchash(cncp->name, cncp->namelen, cncp->dcp)].length--; - cfsnc_stat.lru_rm++; /* zapped a valid entry */ - hashrem(cncp); - iput(CTOI(cncp->cp)); - /* VN_RELE(CTOV(cncp->dcp)); */ - /* crfree(cncp->cred); */ - } - /* - * Put a hold on the current vnodes and fill in the cache entry. - */ - iget((CTOI(cp))->i_sb, CTOI(cp)->i_ino); - /* VN_HOLD(CTOV(dcp)); */ - /* XXXX crhold(cred); */ - cncp->dcp = dcp; - cncp->cp = cp; - cncp->namelen = namelen; - /* cncp->cred = cred; */ - - memcpy(cncp->name, name, (unsigned)namelen); - - /* Insert into the lru and hash chains. */ - - lruins(cncp, (struct cfscache *) &cfsnc_lru); - hashins(cncp, (struct cfscache *)&cfsnchash[hash]); - cfsnchash[hash].length++; /* Used for tuning */ - CDEBUG(D_CACHE, "Entering:\n"); - coda_print_ce(cncp); -} - -/* - * Find the (dir cnode, name) pair in the cache, if it's cred - * matches the input, return it, otherwise return 0 - */ - -struct cnode * -cfsnc_lookup(struct cnode *dcp, register const char *name, int namelen) -{ - register int hash; - register struct cfscache *cncp; - /* this should go into a callback funcntion for /proc/sys - don't know how at the moment? */ - if (cfsnc_flushme == 1) { - cfsnc_flush(); - cfsnc_flushme = 0; - } - - if (cfsnc_procsize != 10000*cfsnc_hashsize + cfsnc_size ) { - int hsh = cfsnc_procsize/10000; - int siz = cfsnc_procsize%10000; - int rc; - - if ( (hsh > 1) && (siz > 2) ) { - rc = cfsnc_resize(hsh, siz); - if ( !rc ) { - printk("Coda:cache size (hash,size) (%d,%d)\n", - hsh, siz); - } else { - printk("Coda: cache resize failed\n"); - } - } - } - - if (cfsnc_use == 0) /* Cache is off */ - return((struct cnode *) 0); - - if (namelen > CFSNC_NAMELEN) { - CDEBUG(D_CACHE,"long name lookup %s\n",name); - cfsnc_stat.long_name_lookups++; /* record stats */ - return((struct cnode *) 0); - } - - /* Use the hash function to locate the starting point, - then the search routine to go down the list looking for - the correct cred. - */ - - hash = nchash(name, namelen, dcp); - CDEBUG(D_CACHE, "Calling find with name %s, dcp %d, hash %d\n", - name, (int) dcp, (int) hash); - cncp = cfsnc_find(dcp, name, namelen, hash); - if (cncp == (struct cfscache *) 0) { - cfsnc_stat.misses++; /* record miss */ - return((struct cnode *) 0); - } - - cfsnc_stat.hits++; - - /* put this entry at the mru end of the LRU */ - lrurem(cncp); - lruins(cncp, (struct cfscache *) &cfsnc_lru); - - /* move it to the front of the hash chain */ - /* don't need to change the hash bucket length */ - hashrem(cncp); - hashins(cncp, (struct cfscache *) &cfsnchash[hash]); - - CDEBUG(D_CACHE, "lookup: dcp 0x%x, name %s, cp 0x%x\n", - (int) dcp, name, (int) cncp->cp); - - return(cncp->cp); -} - -/* - * Remove all entries with a parent which has the input fid. - */ - -void -cfsnc_zapParentfid(ViceFid *fid) -{ - /* To get to a specific fid, we might either have another hashing - function or do a sequential search through the cache for the - appropriate entries. The later may be acceptable since I don't - think callbacks or whatever Case 1 covers are frequent occurences. - */ - register struct cfscache *cncp, *ncncp; - register int i; - - if (cfsnc_use == 0) /* Cache is off */ - return; - - CDEBUG(D_CACHE, " fid 0x%lx, 0x%lx, 0x%lx \n", - fid->Volume, fid->Vnode, fid->Unique); - - cfsnc_stat.zapPfids++; - - for (i = 0; i < cfsnc_hashsize; i++) { - - /* - * Need to save the hash_next pointer in case we remove the - * entry. remove causes hash_next to point to itself. - */ - - for (cncp = cfsnchash[i].hash_next; - cncp != (struct cfscache *) &cfsnchash[i]; - cncp = ncncp) { - ncncp = cncp->hash_next; - if ( coda_fideq(&cncp->dcp->c_fid, fid) ) { - cfsnchash[i].length--; /* Used for tuning */ - cfsnc_remove(cncp); - } - } - } -} - -/* - * Remove all entries which have the same fid as the input - */ -void -cfsnc_zapfid(ViceFid *fid) -{ - /* See comment for zapParentfid. This routine will be used - if attributes are being cached. - */ - register struct cfscache *cncp, *ncncp; - register int i; - - if (cfsnc_use == 0) /* Cache is off */ - return; - - CDEBUG(D_CACHE, "Zapfid: fid 0x%lx, 0x%lx, 0x%lx \n", - fid->Volume, fid->Vnode, fid->Unique); - - cfsnc_stat.zapFids++; - - for (i = 0; i < cfsnc_hashsize; i++) { - for (cncp = cfsnchash[i].hash_next; - cncp != (struct cfscache *) &cfsnchash[i]; - cncp = ncncp) { - ncncp = cncp->hash_next; - if (coda_fideq(&(cncp->cp->c_fid), fid)) { - CDEBUG(D_CACHE, "Found cncp: name %s\n", cncp->name); - cfsnchash[i].length--; /* Used for tuning */ - cfsnc_remove(cncp); - } - } - } -} - - -/* - * Remove all entries which have the (dir vnode, name) pair - */ -void -cfsnc_zapfile(struct cnode *dcp, register const char *name, int length) -{ - /* use the hash function to locate the file, then zap all - entries of it regardless of the cred. - */ - register struct cfscache *cncp; - int hash; - - if (cfsnc_use == 0) /* Cache is off */ - return; - - CDEBUG(D_CACHE,"Zapfile: dcp 0x%x name %s \n", - (int) dcp, name); - - if (length > CFSNC_NAMELEN) { - cfsnc_stat.long_remove++; /* record stats */ - return; - } - - cfsnc_stat.zapFile++; - - hash = nchash(name, length, dcp); - /* remove entries: remember they might exist for more than a - single cred */ - while ( (cncp = cfsnc_find(dcp, name, length, hash)) != NULL ) { - cfsnchash[hash].length--; - cfsnc_remove(cncp); - } -} - -/* - * Remove all the entries for a particular user. Used when tokens expire. - * A user is determined by his/her effective user id (id_uid). - */ - -void -cfsnc_purge_user(struct CodaCred *cred) -{ - /* I think the best approach is to go through the entire cache - via HASH or whatever and zap all entries which match the - input cred. Or just flush the whole cache. - It might be best to go through on basis of LRU since cache - will almost always be full and LRU is more straightforward. - */ - - register struct cfscache *cncp; - int hash; - - if (cfsnc_use == 0) /* Cache is off */ - return; - - CDEBUG(D_CACHE,"ZapDude: uid %ld\n",cred->cr_uid); - cfsnc_stat.zapUsers++; - - for (cncp = cfsnc_lru.lru_next; - cncp != (struct cfscache *) &cfsnc_lru; - cncp = cncp->lru_next) { - - if ((CFSNC_VALID(cncp)) && - ((cncp->cred)->cr_uid == cred->cr_uid)) { - /* Seems really ugly, but we have to decrement the appropriate - hash bucket length here, so we have to find the hash bucket - */ - hash = nchash(cncp->name, cncp->namelen, cncp->dcp); - cfsnchash[hash].length--; /* For performance tuning */ - - cfsnc_remove(cncp); - } - } -} - -/* - * Flush the entire name cache. In response to a flush of the Venus cache. - */ - -void -cfsnc_flush(void) -{ - /* One option is to deallocate the current name cache and - call init to start again. Or just deallocate, then rebuild. - Or again, we could just go through the array and zero the - appropriate fields. - */ - - /* - * Go through the whole lru chain and kill everything as we go. - * I don't use remove since that would rebuild the lru chain - * as it went and that seemed unneccesary. - */ - register struct cfscache *cncp; - int i; - - if ((cfsnc_use == 0 || cfsnc_initialized == 0) && (cfsnc_force == 0) ) - return; - - cfsnc_stat.Flushes++; - - for (cncp = cfsnc_lru.lru_next; - cncp != (struct cfscache *) &cfsnc_lru; - cncp = cncp->lru_next) { - if ( cncp->cp ) { - hashrem(cncp); /* only zero valid nodes */ - hashnull(cncp); - iput(CTOI(cncp->cp)); - /* crfree(cncp->cred); */ - memset(DATA_PART(cncp), 0, DATA_SIZE); - } - } - - for (i = 0; i < cfsnc_hashsize; i++) - cfsnchash[i].length = 0; -} - -/* - * This routine replaces a ViceFid in the name cache with another. - * It is added to allow Venus during reintegration to replace - * locally allocated temp fids while disconnected with global fids - * even when the reference count on those fids are not zero. - */ -void -cfsnc_replace(ViceFid *f1, ViceFid *f2) -{ - /* - * Replace f1 with f2 throughout the name cache - */ - int hash; - register struct cfscache *cncp; - - CDEBUG(D_CACHE, - "cfsnc_replace fid_1 = (%lx.%lx.%lx) and fid_2 = (%lx.%lx.%lx)\n", - f1->Volume, f1->Vnode, f1->Unique, - f2->Volume, f2->Vnode, f2->Unique); - - for (hash = 0; hash < cfsnc_hashsize; hash++) { - for (cncp = cfsnchash[hash].hash_next; - cncp != (struct cfscache *) &cfsnchash[hash]; - cncp = cncp->hash_next) { - if (!memcmp(&cncp->cp->c_fid, f1, sizeof(ViceFid))) { - memcpy(&cncp->cp->c_fid, f2, sizeof(ViceFid)); - continue; /* no need to check cncp->dcp now */ - } - if (!memcmp(&cncp->dcp->c_fid, f1, sizeof(ViceFid))) - memcpy(&cncp->dcp->c_fid, f2, sizeof(ViceFid)); - } - } -} - -/* - * Debugging routines - */ - -/* - * This routine should print out all the hash chains to the console. - */ - -void -print_cfsnc(void) -{ - int hash; - register struct cfscache *cncp; - - for (hash = 0; hash < cfsnc_hashsize; hash++) { - printk("\nhash %d\n",hash); - - for (cncp = cfsnchash[hash].hash_next; - cncp != (struct cfscache *)&cfsnchash[hash]; - cncp = cncp->hash_next) { - printk("cp 0x%x dcp 0x%x cred 0x%x name %s ino %d count %d dev %d\n", - (int)cncp->cp, (int)cncp->dcp, - (int)cncp->cred, cncp->name, CTOI(cncp->cp)->i_count, CTOI(cncp->cp)->i_count, CTOI(cncp->cp)->i_dev); - } - } -} - -int -cfsnc_get_info(char *buffer, char **start, off_t offset, int length, int dummy) -{ - int hash; - int len=0; - off_t pos=0; - off_t begin; - struct cfscache *cncp; - char tmpbuf[80]; - - if (offset < 80) - len += sprintf(buffer, "%-79s\n", - "hash len volume vnode unique name ino pino ct"); - if ( !cfsnc_initialized ) { - *start = buffer; - return len; - } - pos = 80; - for (hash = 0; hash < cfsnc_hashsize; hash++) { - for (cncp = cfsnchash[hash].hash_next; - cncp != (struct cfscache *)&cfsnchash[hash]; - cncp = cncp->hash_next) { - pos += 80; - if (pos < offset) - continue; - sprintf(tmpbuf, "%4d %3d %8x %8x %8x %16s %10ld %10ld %2d", - hash, cfsnchash[hash].length, (int) cncp->cp->c_fid.Volume, - (int) cncp->cp->c_fid.Vnode, (int) cncp->cp->c_fid.Unique , cncp->name, - CTOI(cncp->cp)->i_ino, - CTOI(cncp->dcp)->i_ino, - CTOI(cncp->cp)->i_count); - len += sprintf(buffer+len, "%-79s\n", tmpbuf); - if(len >= length) - break; - } - if(len>= length) - break; - } - begin = len - (pos - offset); - *start = buffer + begin; - len -= begin; - if(len>length) - len = length; - return len; -} - -int -cfsnc_nc_info(char *buffer, char **start, off_t offset, int length, int dummy) -{ - int len=0; - off_t begin; - - cfsnc_gather_stats(); - - /* this works as long as we are below 1024 characters! */ - len += sprintf(buffer,"Coda minicache statistics\n\n"); - len += sprintf(buffer+len, "cfsnc_hits : %d\n", cfsnc_stat.hits); - len += sprintf(buffer+len, "cfsnc_misses : %d\n", cfsnc_stat.misses); - len += sprintf(buffer+len, "cfsnc_enters : %d\n", cfsnc_stat.enters); - len += sprintf(buffer+len, "cfsnc_dbl_enters : %d\n", cfsnc_stat.dbl_enters); - len += sprintf(buffer+len, "cfsnc_long_name_enters : %d\n", cfsnc_stat.long_name_enters); - len += sprintf(buffer+len, "cfsnc_long_name_lookups : %d\n", cfsnc_stat.long_name_lookups); - len += sprintf(buffer+len, "cfsnc_long_remove : %d\n", cfsnc_stat.long_remove); - len += sprintf(buffer+len, "cfsnc_lru_rm : %d\n", cfsnc_stat.lru_rm); - len += sprintf(buffer+len, "cfsnc_zapPfids : %d\n", cfsnc_stat.zapPfids); - len += sprintf(buffer+len, "cfsnc_zapFids : %d\n", cfsnc_stat.zapFids); - len += sprintf(buffer+len, "cfsnc_zapFile : %d\n", cfsnc_stat.zapFile); - len += sprintf(buffer+len, "cfsnc_zapUsers : %d\n", cfsnc_stat.zapUsers); - len += sprintf(buffer+len, "cfsnc_Flushes : %d\n", cfsnc_stat.Flushes); - len += sprintf(buffer+len, "cfsnc_SumLen : %d\n", cfsnc_stat.Sum_bucket_len); - len += sprintf(buffer+len, "cfsnc_Sum2Len : %d\n", cfsnc_stat.Sum2_bucket_len); - len += sprintf(buffer+len, "cfsnc_# 0 len : %d\n", cfsnc_stat.Num_zero_len); - len += sprintf(buffer+len, "cfsnc_MaxLen : %d\n", cfsnc_stat.Max_bucket_len); - len += sprintf(buffer+len, "cfsnc_SearchLen : %d\n", cfsnc_stat.Search_len); - begin = offset; - *start = buffer + begin; - len -= begin; - - if(len>length) - len = length; - if (len< 0) - len = 0; - return len; -} - - - -void -coda_print_ce(struct cfscache *ce) -{ -CDEBUG(D_CACHE, "cp 0x%x, dcp 0x%x, name %s, inod 0x%x, ino %d, count %d, dev %d\n", - (int)ce->cp, (int)ce->dcp, ce->name, (int)CTOI(ce->cp),(int)CTOI(ce->cp)->i_ino, CTOI(ce->cp)->i_count, CTOI(ce->cp)->i_dev); -} - -static void -cfsnc_gather_stats(void) -{ - int i, max = 0, sum = 0, temp, zeros = 0, ave, n; - - for (i = 0; i < cfsnc_hashsize; i++) { - if (cfsnchash[i].length) { - sum += cfsnchash[i].length; - } else { - zeros++; - } - - if (cfsnchash[i].length > max) - max = cfsnchash[i].length; - } - -/* - * When computing the Arithmetic mean, only count slots which - * are not empty in the distribution. - */ - cfsnc_stat.Sum_bucket_len = sum; - cfsnc_stat.Num_zero_len = zeros; - cfsnc_stat.Max_bucket_len = max; - - if ((n = cfsnc_hashsize - zeros) > 0) - ave = sum / n; - else - ave = 0; - - sum = 0; - for (i = 0; i < cfsnc_hashsize; i++) { - if (cfsnchash[i].length) { - temp = cfsnchash[i].length - ave; - sum += temp * temp; - } - } - cfsnc_stat.Sum2_bucket_len = sum; -} - -/* - * The purpose of this routine is to allow the hash and cache sizes to be - * changed dynamically. This should only be used in controlled environments, - * it makes no effort to lock other users from accessing the cache while it - * is in an improper state (except by turning the cache off). - */ -int -cfsnc_resize(int hashsize, int heapsize) -{ - if ( !cfsnc_use ) - return 0; - - if ((hashsize % 2) || (heapsize % 2)) { /* Illegal hash or cache sizes */ - return(EINVAL); - } - - cfsnc_use = 0; /* Turn the cache off */ - cfsnc_force = 1; /* otherwise we can't flush */ - - cfsnc_flush(); /* free any cnodes in the cache */ - cfsnc_force = 0; - - /* WARNING: free must happen *before* size is reset */ - CODA_FREE(cfsncheap,TOTAL_CACHE_SIZE); - CODA_FREE(cfsnchash,TOTAL_HASH_SIZE); - - cfsnc_hashsize = hashsize; - cfsnc_size = heapsize; - - cfsnc_init(); /* Set up a cache with the new size */ - - cfsnc_use = 1; /* Turn the cache back on */ - return(0); -} - - - |