Blame view
net/9p/util.c
3.26 KB
bd238fb43
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 |
/* * net/9p/util.c * * This file contains some helper functions * * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to: * Free Software Foundation * 51 Franklin Street, Fifth Floor * Boston, MA 02111-1301 USA * */ #include <linux/module.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/sched.h> #include <linux/parser.h> #include <linux/idr.h> |
5a0e3ad6a
|
33 |
#include <linux/slab.h> |
bd238fb43
|
34 |
#include <net/9p/9p.h> |
ee443996a
|
35 36 37 38 39 40 |
/** * struct p9_idpool - per-connection accounting for tag idpool * @lock: protects the pool * @pool: idr to allocate tag id from * */ |
bd238fb43
|
41 |
struct p9_idpool { |
dea7bbb60
|
42 |
spinlock_t lock; |
bd238fb43
|
43 44 |
struct idr pool; }; |
ee443996a
|
45 46 47 48 |
/** * p9_idpool_create - create a new per-connection id pool * */ |
bd238fb43
|
49 50 51 52 53 54 55 |
struct p9_idpool *p9_idpool_create(void) { struct p9_idpool *p; p = kmalloc(sizeof(struct p9_idpool), GFP_KERNEL); if (!p) return ERR_PTR(-ENOMEM); |
dea7bbb60
|
56 |
spin_lock_init(&p->lock); |
bd238fb43
|
57 58 59 60 61 |
idr_init(&p->pool); return p; } EXPORT_SYMBOL(p9_idpool_create); |
ee443996a
|
62 63 |
/** * p9_idpool_destroy - create a new per-connection id pool |
25985edce
|
64 |
* @p: idpool to destroy |
ee443996a
|
65 |
*/ |
bd238fb43
|
66 67 68 69 70 71 72 73 74 |
void p9_idpool_destroy(struct p9_idpool *p) { idr_destroy(&p->pool); kfree(p); } EXPORT_SYMBOL(p9_idpool_destroy); /** * p9_idpool_get - allocate numeric id from pool |
ee443996a
|
75 |
* @p: pool to allocate from |
bd238fb43
|
76 |
* |
ee443996a
|
77 |
* Bugs: This seems to be an awful generic function, should it be in idr.c with |
bd238fb43
|
78 79 80 81 82 83 84 |
* the lock included in struct idr? */ int p9_idpool_get(struct p9_idpool *p) { int i = 0; int error; |
d0c447180
|
85 |
unsigned long flags; |
bd238fb43
|
86 87 |
retry: |
eeff66ef6
|
88 |
if (idr_pre_get(&p->pool, GFP_NOFS) == 0) |
fe1cbabae
|
89 |
return -1; |
bd238fb43
|
90 |
|
dea7bbb60
|
91 |
spin_lock_irqsave(&p->lock, flags); |
bd238fb43
|
92 93 94 |
/* no need to store exactly p, we just need something non-null */ error = idr_get_new(&p->pool, p, &i); |
dea7bbb60
|
95 |
spin_unlock_irqrestore(&p->lock, flags); |
bd238fb43
|
96 97 98 99 100 |
if (error == -EAGAIN) goto retry; else if (error) return -1; |
5d3851530
|
101 102 |
p9_debug(P9_DEBUG_MUX, " id %d pool %p ", i, p); |
bd238fb43
|
103 104 105 106 107 108 |
return i; } EXPORT_SYMBOL(p9_idpool_get); /** * p9_idpool_put - release numeric id from pool |
ee443996a
|
109 110 |
* @id: numeric id which is being released * @p: pool to release id into |
bd238fb43
|
111 |
* |
ee443996a
|
112 |
* Bugs: This seems to be an awful generic function, should it be in idr.c with |
bd238fb43
|
113 114 115 116 117 |
* the lock included in struct idr? */ void p9_idpool_put(int id, struct p9_idpool *p) { |
d0c447180
|
118 |
unsigned long flags; |
51a87c552
|
119 |
|
5d3851530
|
120 121 |
p9_debug(P9_DEBUG_MUX, " id %d pool %p ", id, p); |
51a87c552
|
122 |
|
dea7bbb60
|
123 |
spin_lock_irqsave(&p->lock, flags); |
bd238fb43
|
124 |
idr_remove(&p->pool, id); |
dea7bbb60
|
125 |
spin_unlock_irqrestore(&p->lock, flags); |
bd238fb43
|
126 127 128 129 130 |
} EXPORT_SYMBOL(p9_idpool_put); /** * p9_idpool_check - check if the specified id is available |
ee443996a
|
131 132 |
* @id: id to check * @p: pool to check |
bd238fb43
|
133 |
*/ |
ee443996a
|
134 |
|
bd238fb43
|
135 136 137 138 139 |
int p9_idpool_check(int id, struct p9_idpool *p) { return idr_find(&p->pool, id) != NULL; } EXPORT_SYMBOL(p9_idpool_check); |
ee443996a
|
140 |