diff options
Diffstat (limited to 'sys/dev/null/null.c')
| -rw-r--r-- | sys/dev/null/null.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/sys/dev/null/null.c b/sys/dev/null/null.c index 3005c19..04619b2 100644 --- a/sys/dev/null/null.c +++ b/sys/dev/null/null.c @@ -65,8 +65,6 @@ static struct cdevsw zero_cdevsw = { .d_flags = D_MMAP_ANON, }; -static void *zbuf; - /* ARGSUSED */ static int null_write(struct cdev *dev __unused, struct uio *uio, int flags __unused) @@ -95,10 +93,19 @@ null_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data __unused, static int zero_read(struct cdev *dev __unused, struct uio *uio, int flags __unused) { + void *zbuf; + ssize_t len; int error = 0; - while (uio->uio_resid > 0 && error == 0) - error = uiomove(zbuf, MIN(uio->uio_resid, PAGE_SIZE), uio); + KASSERT(uio->uio_rw == UIO_READ, + ("Can't be in %s for write", __func__)); + zbuf = __DECONST(void *, zero_region); + while (uio->uio_resid > 0 && error == 0) { + len = uio->uio_resid; + if (len > ZERO_REGION_SIZE) + len = ZERO_REGION_SIZE; + error = uiomove(zbuf, len, uio); + } return (error); } @@ -111,7 +118,6 @@ null_modevent(module_t mod __unused, int type, void *data __unused) case MOD_LOAD: if (bootverbose) printf("null: <null device, zero device>\n"); - zbuf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK | M_ZERO); null_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &null_cdevsw, 0, NULL, UID_ROOT, GID_WHEEL, 0666, "null"); zero_dev = make_dev_credf(MAKEDEV_ETERNAL_KLD, &zero_cdevsw, 0, @@ -121,7 +127,6 @@ null_modevent(module_t mod __unused, int type, void *data __unused) case MOD_UNLOAD: destroy_dev(null_dev); destroy_dev(zero_dev); - free(zbuf, M_TEMP); break; case MOD_SHUTDOWN: |
