d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Convert md(4) to use alloc_unr(9) and alloc_unr_specific(9) for unit

Browse Source 
number allocation. The old approach had some problems such as it allowed
an overflow to occur in the unit number calculation.

PR:		kern/122288
This commit is contained in:
Jaakko Heinonen 2010-07-22 10:24:28 +00:00
parent e2b801ddd9
commit f4e7c5a894
1 changed files with 20 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
sys/dev/md/md.c
View File

@ -130,6 +130,7 @@ static void g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp
static int mdunits;
static struct cdev *status_dev = 0;
static struct sx md_sx;
static struct unrhdr *md_uh;
static d_ioctl_t mdctlioctl;
@ -748,20 +749,20 @@ mdfind(int unit)
static struct md_s *
mdnew(int unit, int *errp, enum md_types type)
{
struct md_s *sc, *sc2;
int error, max = -1;
struct md_s *sc;
int error;
*errp = 0;
LIST_FOREACH(sc2, &md_softc_list, list) {
if (unit == sc2->unit) {
*errp = EBUSY;
return (NULL);
}
if (unit == -1 && sc2->unit > max)
max = sc2->unit;
}
if (unit == -1)
unit = max + 1;
unit = alloc_unr(md_uh);
else
unit = alloc_unr_specific(md_uh, unit);
if (unit == -1) {
*errp = EBUSY;
return (NULL);
}
sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
sc->type = type;
bioq_init(&sc->bio_queue);
@ -774,6 +775,7 @@ mdnew(int unit, int *errp, enum md_types type)
return (sc);
LIST_REMOVE(sc, list);
mtx_destroy(&sc->queue_mtx);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
*errp = error;
return (NULL);
@ -1012,6 +1014,7 @@ mddestroy(struct md_s *sc, struct thread *td)
uma_zdestroy(sc->uma);
LIST_REMOVE(sc, list);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
return (0);
}
@ -1097,8 +1100,11 @@ xmdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread
}
if (mdio->md_options & MD_AUTOUNIT)
sc = mdnew(-1, &error, mdio->md_type);
else
else {
if (mdio->md_unit > INT_MAX)
return (EINVAL);
sc = mdnew(mdio->md_unit, &error, mdio->md_type);
}
if (sc == NULL)
return (error);
if (mdio->md_options & MD_AUTOUNIT)
@ -1226,6 +1232,7 @@ g_md_init(struct g_class *mp __unused)
mod = NULL;
sx_init(&md_sx, "MD config lock");
g_topology_unlock();
md_uh = new_unrhdr(0, INT_MAX, NULL);
#ifdef MD_ROOT_SIZE
sx_xlock(&md_sx);
md_preloaded(mfs_root.start, sizeof(mfs_root.start));
@ -1322,4 +1329,5 @@ g_md_fini(struct g_class *mp __unused)
sx_destroy(&md_sx);
if (status_dev != NULL)
destroy_dev(status_dev);
delete_unrhdr(md_uh);
}