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kern_fileassoc.c revision 1.30.10.1
      1  1.30.10.1      yamt /* $NetBSD: kern_fileassoc.c,v 1.30.10.1 2008/05/16 02:25:25 yamt Exp $ */
      2        1.1      elad 
      3        1.1      elad /*-
      4        1.1      elad  * Copyright (c) 2006 Elad Efrat <elad (at) NetBSD.org>
      5        1.1      elad  * All rights reserved.
      6        1.1      elad  *
      7        1.1      elad  * Redistribution and use in source and binary forms, with or without
      8        1.1      elad  * modification, are permitted provided that the following conditions
      9        1.1      elad  * are met:
     10        1.1      elad  * 1. Redistributions of source code must retain the above copyright
     11        1.1      elad  *    notice, this list of conditions and the following disclaimer.
     12        1.1      elad  * 2. Redistributions in binary form must reproduce the above copyright
     13        1.1      elad  *    notice, this list of conditions and the following disclaimer in the
     14        1.1      elad  *    documentation and/or other materials provided with the distribution.
     15       1.19      elad  * 3. The name of the author may not be used to endorse or promote products
     16        1.1      elad  *    derived from this software without specific prior written permission.
     17        1.1      elad  *
     18        1.1      elad  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     19        1.1      elad  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     20        1.1      elad  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     21        1.1      elad  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     22        1.1      elad  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     23        1.1      elad  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     24        1.1      elad  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     25        1.1      elad  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     26        1.1      elad  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     27        1.1      elad  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     28        1.1      elad  */
     29        1.1      elad 
     30        1.7   xtraeme #include <sys/cdefs.h>
     31  1.30.10.1      yamt __KERNEL_RCSID(0, "$NetBSD: kern_fileassoc.c,v 1.30.10.1 2008/05/16 02:25:25 yamt Exp $");
     32       1.13      yamt 
     33       1.13      yamt #include "opt_fileassoc.h"
     34        1.7   xtraeme 
     35        1.1      elad #include <sys/param.h>
     36        1.1      elad #include <sys/mount.h>
     37        1.1      elad #include <sys/queue.h>
     38        1.1      elad #include <sys/vnode.h>
     39        1.1      elad #include <sys/namei.h>
     40        1.1      elad #include <sys/exec.h>
     41        1.1      elad #include <sys/proc.h>
     42        1.1      elad #include <sys/inttypes.h>
     43        1.1      elad #include <sys/errno.h>
     44        1.1      elad #include <sys/fileassoc.h>
     45       1.14      yamt #include <sys/specificdata.h>
     46        1.3      elad #include <sys/hash.h>
     47        1.9     blymn #include <sys/fstypes.h>
     48       1.14      yamt #include <sys/kmem.h>
     49       1.14      yamt #include <sys/once.h>
     50       1.13      yamt 
     51       1.22      elad #define	FILEASSOC_INITIAL_TABLESIZE	128
     52       1.22      elad 
     53        1.9     blymn static struct fileassoc_hash_entry *
     54        1.9     blymn fileassoc_file_lookup(struct vnode *, fhandle_t *);
     55        1.9     blymn static struct fileassoc_hash_entry *
     56        1.9     blymn fileassoc_file_add(struct vnode *, fhandle_t *);
     57       1.22      elad static struct fileassoc_table *fileassoc_table_resize(struct fileassoc_table *);
     58       1.22      elad 
     59       1.14      yamt static specificdata_domain_t fileassoc_domain;
     60       1.16      yamt static specificdata_key_t fileassoc_mountspecific_key;
     61       1.25      yamt static ONCE_DECL(control);
     62       1.14      yamt 
     63        1.3      elad /*
     64        1.3      elad  * Hook entry.
     65        1.3      elad  * Includes the hook name for identification and private hook clear callback.
     66        1.3      elad  */
     67       1.14      yamt struct fileassoc {
     68       1.14      yamt 	LIST_ENTRY(fileassoc) list;
     69       1.14      yamt 	const char *name;			/* name. */
     70       1.14      yamt 	fileassoc_cleanup_cb_t cleanup_cb;	/* clear callback. */
     71       1.14      yamt 	specificdata_key_t key;
     72        1.3      elad };
     73        1.3      elad 
     74       1.14      yamt static LIST_HEAD(, fileassoc) fileassoc_list;
     75       1.14      yamt 
     76       1.20      elad /* An entry in the per-mount hash table. */
     77        1.3      elad struct fileassoc_hash_entry {
     78        1.9     blymn 	fhandle_t *handle;				/* File handle */
     79       1.14      yamt 	specificdata_reference data;			/* Hooks. */
     80       1.23      elad 	u_int nassocs;					/* # of hooks. */
     81        1.3      elad 	LIST_ENTRY(fileassoc_hash_entry) entries;	/* List pointer. */
     82        1.3      elad };
     83        1.3      elad 
     84        1.3      elad LIST_HEAD(fileassoc_hashhead, fileassoc_hash_entry);
     85        1.3      elad 
     86        1.3      elad struct fileassoc_table {
     87        1.3      elad 	struct fileassoc_hashhead *hash_tbl;
     88        1.3      elad 	size_t hash_size;				/* Number of slots. */
     89        1.3      elad 	u_long hash_mask;
     90       1.22      elad 	size_t hash_used;				/* # of used slots. */
     91       1.14      yamt 	specificdata_reference data;
     92        1.3      elad };
     93        1.8     blymn 
     94        1.1      elad /*
     95        1.9     blymn  * Hashing function: Takes a number modulus the mask to give back an
     96        1.9     blymn  * index into the hash table.
     97        1.1      elad  */
     98        1.9     blymn #define FILEASSOC_HASH(tbl, handle)	\
     99       1.10     blymn 	(hash32_buf((handle), FHANDLE_SIZE(handle), HASH32_BUF_INIT) \
    100        1.1      elad 	 & ((tbl)->hash_mask))
    101        1.1      elad 
    102       1.14      yamt static void *
    103       1.14      yamt file_getdata(struct fileassoc_hash_entry *e, const struct fileassoc *assoc)
    104       1.14      yamt {
    105       1.14      yamt 
    106       1.14      yamt 	return specificdata_getspecific(fileassoc_domain, &e->data,
    107       1.14      yamt 	    assoc->key);
    108       1.14      yamt }
    109       1.14      yamt 
    110       1.14      yamt static void
    111       1.14      yamt file_setdata(struct fileassoc_hash_entry *e, const struct fileassoc *assoc,
    112       1.14      yamt     void *data)
    113       1.14      yamt {
    114       1.14      yamt 
    115       1.14      yamt 	specificdata_setspecific(fileassoc_domain, &e->data, assoc->key,
    116       1.14      yamt 	    data);
    117       1.14      yamt }
    118       1.14      yamt 
    119       1.14      yamt static void
    120       1.14      yamt file_cleanup(struct fileassoc_hash_entry *e, const struct fileassoc *assoc)
    121       1.14      yamt {
    122       1.14      yamt 	fileassoc_cleanup_cb_t cb;
    123       1.14      yamt 	void *data;
    124       1.14      yamt 
    125       1.14      yamt 	cb = assoc->cleanup_cb;
    126       1.14      yamt 	if (cb == NULL) {
    127       1.14      yamt 		return;
    128       1.14      yamt 	}
    129       1.14      yamt 	data = file_getdata(e, assoc);
    130       1.17      yamt 	(*cb)(data);
    131       1.14      yamt }
    132       1.14      yamt 
    133       1.14      yamt static void
    134       1.14      yamt file_free(struct fileassoc_hash_entry *e)
    135       1.14      yamt {
    136       1.14      yamt 	struct fileassoc *assoc;
    137       1.14      yamt 
    138       1.14      yamt 	LIST_REMOVE(e, entries);
    139       1.14      yamt 
    140       1.14      yamt 	LIST_FOREACH(assoc, &fileassoc_list, list) {
    141       1.14      yamt 		file_cleanup(e, assoc);
    142       1.14      yamt 	}
    143       1.14      yamt 	vfs_composefh_free(e->handle);
    144       1.14      yamt 	specificdata_fini(fileassoc_domain, &e->data);
    145       1.14      yamt 	kmem_free(e, sizeof(*e));
    146       1.14      yamt }
    147       1.14      yamt 
    148       1.16      yamt static void
    149       1.16      yamt table_dtor(void *vp)
    150       1.16      yamt {
    151       1.16      yamt 	struct fileassoc_table *tbl = vp;
    152       1.16      yamt 	struct fileassoc_hashhead *hh;
    153       1.16      yamt 	u_long i;
    154       1.16      yamt 
    155       1.16      yamt 	/* Remove all entries from the table and lists */
    156       1.16      yamt 	hh = tbl->hash_tbl;
    157       1.16      yamt 	for (i = 0; i < tbl->hash_size; i++) {
    158       1.16      yamt 		struct fileassoc_hash_entry *mhe;
    159       1.16      yamt 
    160       1.16      yamt 		while ((mhe = LIST_FIRST(&hh[i])) != NULL) {
    161       1.16      yamt 			file_free(mhe);
    162       1.16      yamt 		}
    163       1.16      yamt 	}
    164       1.16      yamt 
    165       1.16      yamt 	/* Remove hash table and sysctl node */
    166  1.30.10.1      yamt 	hashdone(tbl->hash_tbl, HASH_LIST, tbl->hash_mask);
    167       1.16      yamt 	specificdata_fini(fileassoc_domain, &tbl->data);
    168       1.16      yamt 	kmem_free(tbl, sizeof(*tbl));
    169       1.16      yamt }
    170       1.16      yamt 
    171        1.1      elad /*
    172        1.1      elad  * Initialize the fileassoc subsystem.
    173        1.1      elad  */
    174       1.14      yamt static int
    175        1.1      elad fileassoc_init(void)
    176        1.1      elad {
    177       1.16      yamt 	int error;
    178       1.14      yamt 
    179       1.16      yamt 	error = mount_specific_key_create(&fileassoc_mountspecific_key,
    180       1.16      yamt 	    table_dtor);
    181       1.16      yamt 	if (error) {
    182       1.16      yamt 		return error;
    183       1.16      yamt 	}
    184       1.14      yamt 	fileassoc_domain = specificdata_domain_create();
    185       1.14      yamt 
    186       1.14      yamt 	return 0;
    187        1.1      elad }
    188        1.1      elad 
    189        1.1      elad /*
    190        1.1      elad  * Register a new hook.
    191        1.1      elad  */
    192       1.14      yamt int
    193       1.14      yamt fileassoc_register(const char *name, fileassoc_cleanup_cb_t cleanup_cb,
    194       1.14      yamt     fileassoc_t *result)
    195        1.1      elad {
    196       1.14      yamt 	int error;
    197       1.14      yamt 	specificdata_key_t key;
    198       1.14      yamt 	struct fileassoc *assoc;
    199       1.14      yamt 
    200       1.16      yamt 	error = RUN_ONCE(&control, fileassoc_init);
    201       1.16      yamt 	if (error) {
    202       1.16      yamt 		return error;
    203       1.16      yamt 	}
    204       1.14      yamt 	error = specificdata_key_create(fileassoc_domain, &key, NULL);
    205       1.14      yamt 	if (error) {
    206       1.14      yamt 		return error;
    207       1.14      yamt 	}
    208       1.14      yamt 	assoc = kmem_alloc(sizeof(*assoc), KM_SLEEP);
    209       1.14      yamt 	assoc->name = name;
    210       1.14      yamt 	assoc->cleanup_cb = cleanup_cb;
    211       1.14      yamt 	assoc->key = key;
    212       1.14      yamt 	LIST_INSERT_HEAD(&fileassoc_list, assoc, list);
    213       1.14      yamt 	*result = assoc;
    214        1.1      elad 
    215       1.14      yamt 	return 0;
    216        1.1      elad }
    217        1.1      elad 
    218        1.1      elad /*
    219        1.1      elad  * Deregister a hook.
    220        1.1      elad  */
    221        1.1      elad int
    222       1.14      yamt fileassoc_deregister(fileassoc_t assoc)
    223        1.1      elad {
    224        1.1      elad 
    225       1.14      yamt 	LIST_REMOVE(assoc, list);
    226       1.21      elad 	specificdata_key_delete(fileassoc_domain, assoc->key);
    227       1.14      yamt 	kmem_free(assoc, sizeof(*assoc));
    228        1.1      elad 
    229       1.14      yamt 	return 0;
    230        1.1      elad }
    231        1.1      elad 
    232        1.1      elad /*
    233        1.1      elad  * Get the hash table for the specified device.
    234        1.1      elad  */
    235        1.3      elad static struct fileassoc_table *
    236        1.1      elad fileassoc_table_lookup(struct mount *mp)
    237        1.1      elad {
    238       1.25      yamt 	int error;
    239        1.1      elad 
    240       1.25      yamt 	error = RUN_ONCE(&control, fileassoc_init);
    241       1.25      yamt 	if (error) {
    242       1.25      yamt 		return NULL;
    243       1.25      yamt 	}
    244       1.16      yamt 	return mount_getspecific(mp, fileassoc_mountspecific_key);
    245        1.1      elad }
    246        1.1      elad 
    247        1.1      elad /*
    248        1.8     blymn  * Perform a lookup on a hash table.  If hint is non-zero then use the value
    249        1.8     blymn  * of the hint as the identifier instead of performing a lookup for the
    250        1.8     blymn  * fileid.
    251        1.1      elad  */
    252        1.3      elad static struct fileassoc_hash_entry *
    253        1.9     blymn fileassoc_file_lookup(struct vnode *vp, fhandle_t *hint)
    254        1.1      elad {
    255        1.1      elad 	struct fileassoc_table *tbl;
    256        1.1      elad 	struct fileassoc_hashhead *tble;
    257        1.1      elad 	struct fileassoc_hash_entry *e;
    258        1.1      elad 	size_t indx;
    259        1.9     blymn 	fhandle_t *th;
    260        1.1      elad 	int error;
    261        1.1      elad 
    262       1.16      yamt 	tbl = fileassoc_table_lookup(vp->v_mount);
    263       1.16      yamt 	if (tbl == NULL) {
    264       1.16      yamt 		return NULL;
    265       1.16      yamt 	}
    266       1.16      yamt 
    267        1.9     blymn 	if (hint == NULL) {
    268        1.9     blymn 		error = vfs_composefh_alloc(vp, &th);
    269        1.8     blymn 		if (error)
    270        1.8     blymn 			return (NULL);
    271       1.16      yamt 	} else {
    272        1.8     blymn 		th = hint;
    273       1.10     blymn 	}
    274        1.1      elad 
    275        1.8     blymn 	indx = FILEASSOC_HASH(tbl, th);
    276        1.9     blymn 	tble = &(tbl->hash_tbl[indx]);
    277        1.1      elad 
    278        1.1      elad 	LIST_FOREACH(e, tble, entries) {
    279       1.16      yamt 		if (((FHANDLE_FILEID(e->handle)->fid_len ==
    280       1.10     blymn 		     FHANDLE_FILEID(th)->fid_len)) &&
    281        1.9     blymn 		    (memcmp(FHANDLE_FILEID(e->handle), FHANDLE_FILEID(th),
    282       1.11      elad 			   (FHANDLE_FILEID(th))->fid_len) == 0)) {
    283       1.16      yamt 			break;
    284       1.11      elad 		}
    285        1.1      elad 	}
    286        1.1      elad 
    287       1.10     blymn 	if (hint == NULL)
    288       1.10     blymn 		vfs_composefh_free(th);
    289       1.10     blymn 
    290       1.16      yamt 	return e;
    291        1.1      elad }
    292        1.1      elad 
    293        1.1      elad /*
    294        1.1      elad  * Return hook data associated with a vnode.
    295        1.1      elad  */
    296        1.1      elad void *
    297       1.14      yamt fileassoc_lookup(struct vnode *vp, fileassoc_t assoc)
    298        1.1      elad {
    299        1.9     blymn         struct fileassoc_hash_entry *mhe;
    300        1.8     blymn 
    301        1.9     blymn         mhe = fileassoc_file_lookup(vp, NULL);
    302        1.9     blymn         if (mhe == NULL)
    303        1.9     blymn                 return (NULL);
    304        1.1      elad 
    305       1.14      yamt         return file_getdata(mhe, assoc);
    306        1.1      elad }
    307        1.1      elad 
    308       1.22      elad static struct fileassoc_table *
    309       1.22      elad fileassoc_table_resize(struct fileassoc_table *tbl)
    310       1.22      elad {
    311       1.22      elad 	struct fileassoc_table *newtbl;
    312       1.22      elad 	struct fileassoc_hashhead *hh;
    313       1.22      elad 	u_long i;
    314       1.22      elad 
    315       1.22      elad 	/*
    316       1.22      elad 	 * Allocate a new table. Like the condition in fileassoc_file_add(),
    317       1.22      elad 	 * this is also temporary -- just double the number of slots.
    318       1.22      elad 	 */
    319       1.22      elad 	newtbl = kmem_zalloc(sizeof(*newtbl), KM_SLEEP);
    320       1.22      elad 	newtbl->hash_size = (tbl->hash_size * 2);
    321       1.22      elad 	if (newtbl->hash_size < tbl->hash_size)
    322       1.22      elad 		newtbl->hash_size = tbl->hash_size;
    323  1.30.10.1      yamt 	newtbl->hash_tbl = hashinit(newtbl->hash_size, HASH_LIST,
    324  1.30.10.1      yamt 	    true, &newtbl->hash_mask);
    325       1.22      elad 	newtbl->hash_used = 0;
    326       1.22      elad 	specificdata_init(fileassoc_domain, &newtbl->data);
    327       1.22      elad 
    328       1.22      elad 	/* XXX we need to make sure nothing uses fileassoc here! */
    329       1.22      elad 
    330       1.22      elad 	hh = tbl->hash_tbl;
    331       1.22      elad 	for (i = 0; i < tbl->hash_size; i++) {
    332       1.22      elad 		struct fileassoc_hash_entry *mhe;
    333       1.22      elad 
    334       1.22      elad 		while ((mhe = LIST_FIRST(&hh[i])) != NULL) {
    335       1.22      elad 			struct fileassoc_hashhead *vhh;
    336       1.22      elad 			size_t indx;
    337       1.22      elad 
    338       1.22      elad 			LIST_REMOVE(mhe, entries);
    339       1.22      elad 
    340       1.22      elad 			indx = FILEASSOC_HASH(newtbl, mhe->handle);
    341       1.22      elad 			vhh = &(newtbl->hash_tbl[indx]);
    342       1.22      elad 
    343       1.22      elad 			LIST_INSERT_HEAD(vhh, mhe, entries);
    344       1.22      elad 
    345       1.22      elad 			newtbl->hash_used++;
    346       1.22      elad 		}
    347       1.22      elad 	}
    348       1.22      elad 
    349       1.22      elad 	if (tbl->hash_used != newtbl->hash_used)
    350       1.22      elad 		panic("fileassoc_table_resize: inconsistency detected! "
    351       1.22      elad 		    "needed %zu entries, got %zu", tbl->hash_used,
    352       1.22      elad 		    newtbl->hash_used);
    353       1.22      elad 
    354  1.30.10.1      yamt 	hashdone(tbl->hash_tbl, HASH_LIST, tbl->hash_mask);
    355       1.22      elad 	specificdata_fini(fileassoc_domain, &tbl->data);
    356       1.22      elad 	kmem_free(tbl, sizeof(*tbl));
    357       1.22      elad 
    358       1.22      elad 	return (newtbl);
    359       1.22      elad }
    360       1.22      elad 
    361        1.1      elad /*
    362        1.1      elad  * Create a new fileassoc table.
    363        1.1      elad  */
    364       1.23      elad static struct fileassoc_table *
    365       1.22      elad fileassoc_table_add(struct mount *mp)
    366        1.1      elad {
    367        1.1      elad 	struct fileassoc_table *tbl;
    368        1.1      elad 
    369        1.1      elad 	/* Check for existing table for device. */
    370       1.23      elad 	tbl = fileassoc_table_lookup(mp);
    371       1.23      elad 	if (tbl != NULL)
    372       1.23      elad 		return (tbl);
    373        1.1      elad 
    374       1.18      elad 	/* Allocate and initialize a table. */
    375       1.14      yamt 	tbl = kmem_zalloc(sizeof(*tbl), KM_SLEEP);
    376       1.22      elad 	tbl->hash_size = FILEASSOC_INITIAL_TABLESIZE;
    377  1.30.10.1      yamt 	tbl->hash_tbl = hashinit(tbl->hash_size, HASH_LIST, true,
    378  1.30.10.1      yamt 	    &tbl->hash_mask);
    379       1.22      elad 	tbl->hash_used = 0;
    380       1.14      yamt 	specificdata_init(fileassoc_domain, &tbl->data);
    381        1.1      elad 
    382       1.16      yamt 	mount_setspecific(mp, fileassoc_mountspecific_key, tbl);
    383        1.1      elad 
    384       1.23      elad 	return (tbl);
    385        1.1      elad }
    386        1.1      elad 
    387        1.1      elad /*
    388        1.1      elad  * Delete a table.
    389        1.1      elad  */
    390        1.1      elad int
    391        1.1      elad fileassoc_table_delete(struct mount *mp)
    392        1.1      elad {
    393        1.1      elad 	struct fileassoc_table *tbl;
    394        1.1      elad 
    395        1.1      elad 	tbl = fileassoc_table_lookup(mp);
    396        1.1      elad 	if (tbl == NULL)
    397        1.1      elad 		return (EEXIST);
    398        1.1      elad 
    399       1.16      yamt 	mount_setspecific(mp, fileassoc_mountspecific_key, NULL);
    400       1.16      yamt 	table_dtor(tbl);
    401        1.1      elad 
    402        1.1      elad 	return (0);
    403        1.1      elad }
    404        1.1      elad 
    405        1.1      elad /*
    406        1.6  christos  * Run a callback for each hook entry in a table.
    407        1.6  christos  */
    408        1.6  christos int
    409       1.29      elad fileassoc_table_run(struct mount *mp, fileassoc_t assoc, fileassoc_cb_t cb,
    410       1.29      elad     void *cookie)
    411        1.6  christos {
    412        1.6  christos 	struct fileassoc_table *tbl;
    413        1.6  christos 	struct fileassoc_hashhead *hh;
    414        1.6  christos 	u_long i;
    415        1.6  christos 
    416        1.6  christos 	tbl = fileassoc_table_lookup(mp);
    417        1.6  christos 	if (tbl == NULL)
    418        1.6  christos 		return (EEXIST);
    419        1.6  christos 
    420        1.6  christos 	hh = tbl->hash_tbl;
    421        1.6  christos 	for (i = 0; i < tbl->hash_size; i++) {
    422        1.6  christos 		struct fileassoc_hash_entry *mhe;
    423        1.6  christos 
    424        1.6  christos 		LIST_FOREACH(mhe, &hh[i], entries) {
    425       1.14      yamt 			void *data;
    426       1.14      yamt 
    427       1.14      yamt 			data = file_getdata(mhe, assoc);
    428       1.14      yamt 			if (data != NULL)
    429       1.29      elad 				cb(data, cookie);
    430        1.6  christos 		}
    431        1.6  christos 	}
    432        1.6  christos 
    433        1.6  christos 	return (0);
    434        1.6  christos }
    435        1.6  christos 
    436        1.6  christos /*
    437        1.1      elad  * Clear a table for a given hook.
    438        1.1      elad  */
    439        1.1      elad int
    440       1.14      yamt fileassoc_table_clear(struct mount *mp, fileassoc_t assoc)
    441        1.1      elad {
    442        1.1      elad 	struct fileassoc_table *tbl;
    443        1.1      elad 	struct fileassoc_hashhead *hh;
    444        1.1      elad 	u_long i;
    445        1.1      elad 
    446        1.1      elad 	tbl = fileassoc_table_lookup(mp);
    447        1.1      elad 	if (tbl == NULL)
    448        1.1      elad 		return (EEXIST);
    449        1.1      elad 
    450        1.1      elad 	hh = tbl->hash_tbl;
    451        1.1      elad 	for (i = 0; i < tbl->hash_size; i++) {
    452        1.1      elad 		struct fileassoc_hash_entry *mhe;
    453        1.1      elad 
    454        1.1      elad 		LIST_FOREACH(mhe, &hh[i], entries) {
    455       1.14      yamt 			file_cleanup(mhe, assoc);
    456       1.14      yamt 			file_setdata(mhe, assoc, NULL);
    457        1.1      elad 		}
    458        1.1      elad 	}
    459        1.1      elad 
    460        1.1      elad 	return (0);
    461        1.1      elad }
    462        1.1      elad 
    463        1.1      elad /*
    464        1.1      elad  * Add a file entry to a table.
    465        1.1      elad  */
    466        1.3      elad static struct fileassoc_hash_entry *
    467        1.9     blymn fileassoc_file_add(struct vnode *vp, fhandle_t *hint)
    468        1.1      elad {
    469        1.1      elad 	struct fileassoc_table *tbl;
    470        1.1      elad 	struct fileassoc_hashhead *vhh;
    471        1.1      elad 	struct fileassoc_hash_entry *e;
    472        1.1      elad 	size_t indx;
    473        1.9     blymn 	fhandle_t *th;
    474        1.1      elad 	int error;
    475        1.1      elad 
    476       1.12      elad 	if (hint == NULL) {
    477        1.9     blymn 		error = vfs_composefh_alloc(vp, &th);
    478        1.8     blymn 		if (error)
    479        1.8     blymn 			return (NULL);
    480        1.8     blymn 	} else
    481        1.9     blymn 		th = hint;
    482        1.1      elad 
    483        1.9     blymn 	e = fileassoc_file_lookup(vp, th);
    484       1.10     blymn 	if (e != NULL) {
    485       1.10     blymn 		if (hint == NULL)
    486       1.10     blymn 			vfs_composefh_free(th);
    487       1.10     blymn 
    488        1.1      elad 		return (e);
    489       1.10     blymn 	}
    490        1.1      elad 
    491        1.1      elad 	tbl = fileassoc_table_lookup(vp->v_mount);
    492       1.10     blymn 	if (tbl == NULL) {
    493       1.23      elad 		tbl = fileassoc_table_add(vp->v_mount);
    494       1.10     blymn 	}
    495        1.1      elad 
    496        1.9     blymn 	indx = FILEASSOC_HASH(tbl, th);
    497        1.9     blymn 	vhh = &(tbl->hash_tbl[indx]);
    498        1.1      elad 
    499       1.14      yamt 	e = kmem_zalloc(sizeof(*e), KM_SLEEP);
    500        1.9     blymn 	e->handle = th;
    501       1.14      yamt 	specificdata_init(fileassoc_domain, &e->data);
    502        1.1      elad 	LIST_INSERT_HEAD(vhh, e, entries);
    503        1.1      elad 
    504       1.22      elad 	/*
    505       1.22      elad 	 * This decides when we need to resize the table. For now,
    506       1.22      elad 	 * resize it whenever we "filled" up the number of slots it
    507       1.22      elad 	 * has. That's not really true unless of course we had zero
    508       1.22      elad 	 * collisions. Think positive! :)
    509       1.22      elad 	 */
    510       1.22      elad 	if (++(tbl->hash_used) == tbl->hash_size) {
    511       1.22      elad 		struct fileassoc_table *newtbl;
    512       1.22      elad 
    513       1.22      elad 		newtbl = fileassoc_table_resize(tbl);
    514       1.22      elad 		mount_setspecific(vp->v_mount, fileassoc_mountspecific_key,
    515       1.22      elad 		    newtbl);
    516       1.22      elad 	}
    517       1.22      elad 
    518        1.1      elad 	return (e);
    519        1.1      elad }
    520        1.1      elad 
    521        1.1      elad /*
    522        1.1      elad  * Delete a file entry from a table.
    523        1.1      elad  */
    524        1.1      elad int
    525        1.1      elad fileassoc_file_delete(struct vnode *vp)
    526        1.1      elad {
    527       1.23      elad 	struct fileassoc_table *tbl;
    528        1.1      elad 	struct fileassoc_hash_entry *mhe;
    529        1.1      elad 
    530       1.30        ad 	KERNEL_LOCK(1, NULL);
    531       1.30        ad 
    532        1.9     blymn 	mhe = fileassoc_file_lookup(vp, NULL);
    533       1.30        ad 	if (mhe == NULL) {
    534       1.30        ad 		KERNEL_UNLOCK_ONE(NULL);
    535        1.1      elad 		return (ENOENT);
    536       1.30        ad 	}
    537        1.1      elad 
    538       1.14      yamt 	file_free(mhe);
    539        1.1      elad 
    540       1.23      elad 	tbl = fileassoc_table_lookup(vp->v_mount);
    541       1.23      elad 	--(tbl->hash_used); /* XXX gc? */
    542       1.23      elad 
    543       1.30        ad 	KERNEL_UNLOCK_ONE(NULL);
    544       1.30        ad 
    545        1.1      elad 	return (0);
    546        1.1      elad }
    547        1.1      elad 
    548        1.1      elad /*
    549        1.9     blymn  * Add a hook to a vnode.
    550        1.1      elad  */
    551        1.1      elad int
    552       1.14      yamt fileassoc_add(struct vnode *vp, fileassoc_t assoc, void *data)
    553        1.1      elad {
    554        1.1      elad 	struct fileassoc_hash_entry *e;
    555       1.14      yamt 	void *olddata;
    556        1.1      elad 
    557        1.9     blymn 	e = fileassoc_file_lookup(vp, NULL);
    558        1.1      elad 	if (e == NULL) {
    559        1.9     blymn 		e = fileassoc_file_add(vp, NULL);
    560        1.1      elad 		if (e == NULL)
    561        1.1      elad 			return (ENOTDIR);
    562        1.1      elad 	}
    563        1.1      elad 
    564       1.14      yamt 	olddata = file_getdata(e, assoc);
    565       1.14      yamt 	if (olddata != NULL)
    566        1.1      elad 		return (EEXIST);
    567        1.1      elad 
    568       1.14      yamt 	file_setdata(e, assoc, data);
    569        1.1      elad 
    570       1.23      elad 	e->nassocs++;
    571       1.23      elad 
    572        1.1      elad 	return (0);
    573        1.1      elad }
    574        1.1      elad 
    575        1.1      elad /*
    576        1.1      elad  * Clear a hook from a vnode.
    577        1.1      elad  */
    578        1.1      elad int
    579       1.14      yamt fileassoc_clear(struct vnode *vp, fileassoc_t assoc)
    580        1.1      elad {
    581        1.1      elad 	struct fileassoc_hash_entry *mhe;
    582        1.1      elad 
    583        1.9     blymn 	mhe = fileassoc_file_lookup(vp, NULL);
    584        1.1      elad 	if (mhe == NULL)
    585        1.1      elad 		return (ENOENT);
    586        1.1      elad 
    587       1.14      yamt 	file_cleanup(mhe, assoc);
    588       1.14      yamt 	file_setdata(mhe, assoc, NULL);
    589        1.1      elad 
    590       1.23      elad 	--(mhe->nassocs); /* XXX gc? */
    591       1.23      elad 
    592        1.1      elad 	return (0);
    593        1.1      elad }
    594