Add another variation of make_dev(9), make_dev_p(9), that is allowed

to fail and can return useful error code.

Requested by:	jh
Reviewed by:	imp, jh
MFC after:	3 weeks
This commit is contained in:
Konstantin Belousov 2010-06-12 13:22:39 +00:00
parent 76d43557d8
commit f1bb758d4b
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=209106
2 changed files with 58 additions and 25 deletions

View File

@ -55,9 +55,8 @@ struct mtx devmtx;
static void destroy_devl(struct cdev *dev);
static int destroy_dev_sched_cbl(struct cdev *dev,
void (*cb)(void *), void *arg);
static struct cdev *make_dev_credv(int flags,
struct cdevsw *devsw, int unit,
struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
static int make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw,
int unit, struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
va_list ap);
static struct cdev_priv_list cdevp_free_list =
@ -580,20 +579,20 @@ prep_cdevsw(struct cdevsw *devsw, int flags)
mtx_assert(&devmtx, MA_OWNED);
if (devsw->d_flags & D_INIT)
return (1);
return (0);
if (devsw->d_flags & D_NEEDGIANT) {
dev_unlock();
dsw2 = malloc(sizeof *dsw2, M_DEVT,
(flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK);
dev_lock();
if (dsw2 == NULL && !(devsw->d_flags & D_INIT))
return (0);
return (ENOMEM);
} else
dsw2 = NULL;
if (devsw->d_flags & D_INIT) {
if (dsw2 != NULL)
cdevsw_free_devlocked(dsw2);
return (1);
return (0);
}
if (devsw->d_version != D_VERSION_03) {
@ -651,25 +650,28 @@ prep_cdevsw(struct cdevsw *devsw, int flags)
if (dsw2 != NULL)
cdevsw_free_devlocked(dsw2);
return (1);
return (0);
}
static struct cdev *
make_dev_credv(int flags, struct cdevsw *devsw, int unit,
struct ucred *cr, uid_t uid,
gid_t gid, int mode, const char *fmt, va_list ap)
static int
make_dev_credv(int flags, struct cdev **dres, struct cdevsw *devsw, int unit,
struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt,
va_list ap)
{
struct cdev *dev;
int i;
int i, res;
KASSERT((flags & MAKEDEV_WAITOK) == 0 || (flags & MAKEDEV_NOWAIT) == 0,
("make_dev_credv: both WAITOK and NOWAIT specified"));
dev = devfs_alloc(flags);
if (dev == NULL)
return (NULL);
return (ENOMEM);
dev_lock();
if (!prep_cdevsw(devsw, flags)) {
res = prep_cdevsw(devsw, flags);
if (res != 0) {
dev_unlock();
devfs_free(dev);
return (NULL);
return (res);
}
dev = newdev(devsw, unit, dev);
if (flags & MAKEDEV_REF)
@ -682,7 +684,8 @@ make_dev_credv(int flags, struct cdevsw *devsw, int unit,
* XXX: still ??
*/
dev_unlock_and_free();
return (dev);
*dres = dev;
return (0);
}
KASSERT(!(dev->si_flags & SI_NAMED),
("make_dev() by driver %s on pre-existing device (min=%x, name=%s)",
@ -707,7 +710,8 @@ make_dev_credv(int flags, struct cdevsw *devsw, int unit,
notify_create(dev, flags);
return (dev);
*dres = dev;
return (0);
}
struct cdev *
@ -716,10 +720,13 @@ make_dev(struct cdevsw *devsw, int unit, uid_t uid, gid_t gid, int mode,
{
struct cdev *dev;
va_list ap;
int res;
va_start(ap, fmt);
dev = make_dev_credv(0, devsw, unit, NULL, uid, gid, mode, fmt, ap);
res = make_dev_credv(0, &dev, devsw, unit, NULL, uid, gid, mode, fmt,
ap);
va_end(ap);
KASSERT(res == 0 && dev != NULL, ("make_dev: failed make_dev_credv"));
return (dev);
}
@ -729,28 +736,50 @@ make_dev_cred(struct cdevsw *devsw, int unit, struct ucred *cr, uid_t uid,
{
struct cdev *dev;
va_list ap;
int res;
va_start(ap, fmt);
dev = make_dev_credv(0, devsw, unit, cr, uid, gid, mode, fmt, ap);
res = make_dev_credv(0, &dev, devsw, unit, cr, uid, gid, mode, fmt, ap);
va_end(ap);
KASSERT(res == 0 && dev != NULL,
("make_dev_cred: failed make_dev_credv"));
return (dev);
}
struct cdev *
make_dev_credf(int flags, struct cdevsw *devsw, int unit,
struct ucred *cr, uid_t uid,
gid_t gid, int mode, const char *fmt, ...)
make_dev_credf(int flags, struct cdevsw *devsw, int unit, struct ucred *cr,
uid_t uid, gid_t gid, int mode, const char *fmt, ...)
{
struct cdev *dev;
va_list ap;
int res;
va_start(ap, fmt);
dev = make_dev_credv(flags, devsw, unit, cr, uid, gid, mode,
res = make_dev_credv(flags, &dev, devsw, unit, cr, uid, gid, mode,
fmt, ap);
va_end(ap);
return (dev);
KASSERT((flags & MAKEDEV_NOWAIT) != 0 || res == 0,
("make_dev_credf: failed make_dev_credv"));
return (res == 0 ? dev : NULL);
}
int
make_dev_p(int flags, struct cdev **cdev, struct cdevsw *devsw, int unit,
struct ucred *cr, uid_t uid, gid_t gid, int mode, const char *fmt, ...)
{
va_list ap;
int res;
va_start(ap, fmt);
res = make_dev_credv(flags, cdev, devsw, unit, cr, uid, gid, mode,
fmt, ap);
va_end(ap);
KASSERT((flags & MAKEDEV_NOWAIT) != 0 || res == 0,
("make_dev_credf: failed make_dev_credv"));
return (res);
}
static void

View File

@ -270,7 +270,11 @@ struct cdev *make_dev_credf(int _flags,
struct cdevsw *_devsw, int _unit,
struct ucred *_cr, uid_t _uid, gid_t _gid, int _mode,
const char *_fmt, ...) __printflike(8, 9);
struct cdev *make_dev_alias(struct cdev *_pdev, const char *_fmt, ...) __printflike(2, 3);
int make_dev_p(int _flags, struct cdev **_cdev, struct cdevsw *_devsw,
int _unit, struct ucred *_cr, uid_t _uid, gid_t _gid, int _mode,
const char *_fmt, ...) __printflike(9, 10);
struct cdev *make_dev_alias(struct cdev *_pdev, const char *_fmt, ...)
__printflike(2, 3);
void dev_lock(void);
void dev_unlock(void);
void setconf(void);