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authoryongari <yongari@FreeBSD.org>2005-11-17 08:56:21 +0000
committeryongari <yongari@FreeBSD.org>2005-11-17 08:56:21 +0000
commit8b951cd641f7208d199cb37a2533f21094dedddc (patch)
treec18e737d5bbcbf6d854fb1bf9d85458f3c91f392
parent489c59fcd460882eb6abaa791e4117adecff7fe8 (diff)
downloadFreeBSD-src-8b951cd641f7208d199cb37a2533f21094dedddc.zip
FreeBSD-src-8b951cd641f7208d199cb37a2533f21094dedddc.tar.gz
Prefer NULL to 0.
Add missing lock/unlock in sysctl handler. Protect accessing NULL pointer when resource allocation was failed. style(9) Reviewed by: scottl MFC after: 1 week
Diffstat
-rw-r--r--sys/kern/subr_rman.c54
1 files changed, 29 insertions, 25 deletions
diff --git a/sys/kern/subr_rman.c b/sys/kern/subr_rman.c
index 17d2abc..b2d7f84 100644
--- a/sys/kern/subr_rman.c
+++ b/sys/kern/subr_rman.c
@@ -12,7 +12,7 @@
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
- *
+ *
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
@@ -150,7 +150,7 @@ rman_secret_puc_free_resource(struct resource *r)
int
rman_init(struct rman *rm)
{
- static int once;
+ static int once = 0;
if (once == 0) {
once = 1;
@@ -165,7 +165,7 @@ rman_init(struct rman *rm)
TAILQ_INIT(&rm->rm_list);
rm->rm_mtx = malloc(sizeof *rm->rm_mtx, M_RMAN, M_NOWAIT | M_ZERO);
- if (rm->rm_mtx == 0)
+ if (rm->rm_mtx == NULL)
return ENOMEM;
mtx_init(rm->rm_mtx, "rman", NULL, MTX_DEF);
@@ -187,14 +187,14 @@ rman_manage_region(struct rman *rm, u_long start, u_long end)
DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n",
rm->rm_descr, start, end));
r = int_alloc_resource(M_NOWAIT);
- if (r == 0)
+ if (r == NULL)
return ENOMEM;
r->r_start = start;
r->r_end = end;
r->r_rm = rm;
mtx_lock(rm->rm_mtx);
- for (s = TAILQ_FIRST(&rm->rm_list);
+ for (s = TAILQ_FIRST(&rm->rm_list);
s && s->r_end < r->r_start;
s = TAILQ_NEXT(s, r_link))
;
@@ -250,7 +250,7 @@ rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
struct resource_i *r, *s, *rv;
u_long rstart, rend, amask, bmask;
- rv = 0;
+ rv = NULL;
DPRINTF(("rman_reserve_resource: <%s> request: [%#lx, %#lx], length "
"%#lx, flags %u, device %s\n", rm->rm_descr, start, end, count,
@@ -260,7 +260,7 @@ rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
mtx_lock(rm->rm_mtx);
- for (r = TAILQ_FIRST(&rm->rm_list);
+ for (r = TAILQ_FIRST(&rm->rm_list);
r && r->r_end < start;
r = TAILQ_NEXT(r, r_link))
;
@@ -329,14 +329,14 @@ rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
* two new allocations; the second requires but one.
*/
rv = int_alloc_resource(M_NOWAIT);
- if (rv == 0)
+ if (rv == NULL)
goto out;
rv->r_start = rstart;
rv->r_end = rstart + count - 1;
rv->r_flags = flags | RF_ALLOCATED;
rv->r_dev = dev;
rv->r_rm = rm;
-
+
if (s->r_start < rv->r_start && s->r_end > rv->r_end) {
DPRINTF(("splitting region in three parts: "
"[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n",
@@ -347,9 +347,9 @@ rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
* We are allocating in the middle.
*/
r = int_alloc_resource(M_NOWAIT);
- if (r == 0) {
+ if (r == NULL) {
free(rv, M_RMAN);
- rv = 0;
+ rv = NULL;
goto out;
}
r->r_start = rv->r_end + 1;
@@ -405,24 +405,24 @@ rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
(s->r_start & amask) == 0 &&
((s->r_start ^ s->r_end) & bmask) == 0) {
rv = int_alloc_resource(M_NOWAIT);
- if (rv == 0)
+ if (rv == NULL)
goto out;
rv->r_start = s->r_start;
rv->r_end = s->r_end;
- rv->r_flags = s->r_flags &
+ rv->r_flags = s->r_flags &
(RF_ALLOCATED | RF_SHAREABLE | RF_TIMESHARE);
rv->r_dev = dev;
rv->r_rm = rm;
- if (s->r_sharehead == 0) {
+ if (s->r_sharehead == NULL) {
s->r_sharehead = malloc(sizeof *s->r_sharehead,
M_RMAN, M_NOWAIT | M_ZERO);
- if (s->r_sharehead == 0) {
+ if (s->r_sharehead == NULL) {
free(rv, M_RMAN);
- rv = 0;
+ rv = NULL;
goto out;
}
LIST_INIT(s->r_sharehead);
- LIST_INSERT_HEAD(s->r_sharehead, s,
+ LIST_INSERT_HEAD(s->r_sharehead, s,
r_sharelink);
s->r_flags |= RF_FIRSTSHARE;
}
@@ -447,12 +447,12 @@ out:
struct resource_i *whohas;
if (int_rman_activate_resource(rm, rv, &whohas)) {
int_rman_release_resource(rm, rv);
- rv = 0;
+ rv = NULL;
}
}
-
+
mtx_unlock(rm->rm_mtx);
- return (&rv->r_r);
+ return (rv == NULL ? NULL : &rv->r_r);
}
struct resource *
@@ -479,7 +479,7 @@ int_rman_activate_resource(struct rman *rm, struct resource_i *r,
*/
if ((r->r_flags & RF_TIMESHARE) == 0
|| (r->r_flags & RF_ACTIVE) != 0
- || r->r_sharehead == 0) {
+ || r->r_sharehead == NULL) {
r->r_flags |= RF_ACTIVE;
return 0;
}
@@ -529,7 +529,7 @@ rman_await_resource(struct resource *re, int pri, int timo)
if (rv != EBUSY)
return (rv); /* returns with mutex held */
- if (r->r_sharehead == 0)
+ if (r->r_sharehead == NULL)
panic("rman_await_resource");
whohas->r_flags |= RF_WANTED;
rv = msleep(r->r_sharehead, rm->rm_mtx, pri, "rmwait", timo);
@@ -595,9 +595,9 @@ int_rman_release_resource(struct rman *rm, struct resource_i *r)
* Make sure that the sharing list goes away completely
* if the resource is no longer being shared at all.
*/
- if (LIST_NEXT(s, r_sharelink) == 0) {
+ if (LIST_NEXT(s, r_sharelink) == NULL) {
free(s->r_sharehead, M_RMAN);
- s->r_sharehead = 0;
+ s->r_sharehead = NULL;
s->r_flags &= ~RF_FIRSTSHARE;
}
goto out;
@@ -822,10 +822,12 @@ sysctl_rman(SYSCTL_HANDLER_ARGS)
/*
* Find the indexed resource manager
*/
+ mtx_lock(&rman_mtx);
TAILQ_FOREACH(rm, &rman_head, rm_link) {
if (rman_idx-- == 0)
break;
}
+ mtx_unlock(&rman_mtx);
if (rm == NULL)
return (ENOENT);
@@ -848,6 +850,7 @@ sysctl_rman(SYSCTL_HANDLER_ARGS)
/*
* Find the indexed resource and return it.
*/
+ mtx_lock(rm->rm_mtx);
TAILQ_FOREACH(res, &rm->rm_list, r_link) {
if (res_idx-- == 0) {
bzero(&ures, sizeof(ures));
@@ -871,13 +874,14 @@ sysctl_rman(SYSCTL_HANDLER_ARGS)
ures.r_size = res->r_end - res->r_start + 1;
ures.r_flags = res->r_flags;
+ mtx_unlock(rm->rm_mtx);
error = SYSCTL_OUT(req, &ures, sizeof(ures));
return (error);
}
}
+ mtx_unlock(rm->rm_mtx);
return (ENOENT);
}
SYSCTL_NODE(_hw_bus, OID_AUTO, rman, CTLFLAG_RD, sysctl_rman,
"kernel resource manager");
-
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