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/*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*/
/*
* Copyright 2017 Joyent, Inc.
*/
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/sunldi.h>
#include <sys/vnode.h>
#include <sys/eventfd.h>
static major_t eventfd_major = 0;
/* io_submit uses this to validate control block eventfd descriptors */
boolean_t
lx_is_eventfd(file_t *fp)
{
vnode_t *vp = fp->f_vnode;
if (vp->v_type == VCHR && getmajor(vp->v_rdev) == eventfd_major)
return (B_TRUE);
return (B_FALSE);
}
long
lx_eventfd2(uint_t initval, int flags)
{
int err, fd;
int fmode = FREAD | FWRITE;
vnode_t *vp = NULL;
file_t *fp = NULL;
if (flags & ~(EFD_NONBLOCK | EFD_CLOEXEC | EFD_SEMAPHORE))
return (set_errno(EINVAL));
if (flags & EFD_NONBLOCK)
fmode |= FNONBLOCK;
if (falloc((vnode_t *)NULL, fmode, &fp, &fd) != 0)
return (set_errno(EMFILE));
if (ldi_vp_from_name("/dev/eventfd", &vp) != 0) {
/*
* If /dev/eventfd is not available then it is less jarring to
* Linux programs to tell them that the system call is not
* supported instead of reporting an error (ENOENT) they are
* not expecting.
*/
err = ENOTSUP;
goto error;
}
if ((err = VOP_OPEN(&vp, fmode | FKLYR, CRED(), NULL)) != 0) {
VN_RELE(vp);
vp = NULL;
goto error;
}
if (flags & EFD_SEMAPHORE) {
int rv;
if ((err = VOP_IOCTL(vp, EVENTFDIOC_SEMAPHORE, 0, fmode, CRED(),
&rv, NULL)) != 0)
goto error;
}
if (initval != 0) {
uint64_t val = initval;
struct uio auio;
struct iovec aiov;
/* write initial value */
aiov.iov_base = (caddr_t)&val;
aiov.iov_len = sizeof (val);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_loffset = 0;
auio.uio_offset = 0;
auio.uio_resid = sizeof (val);
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_fmode = FWRITE;
if ((err = VOP_WRITE(vp, &auio, FWRITE, CRED(), NULL)) != 0)
goto error;
}
eventfd_major = getmajor(vp->v_rdev);
fp->f_vnode = vp;
mutex_exit(&fp->f_tlock);
setf(fd, fp);
if (flags & EFD_CLOEXEC) {
f_setfd(fd, FD_CLOEXEC);
}
return (fd);
error:
if (fp != NULL) {
setf(fd, NULL);
unfalloc(fp);
}
if (vp != NULL) {
(void) VOP_CLOSE(vp, fmode, 0, 0, CRED(), NULL);
VN_RELE(vp);
}
return (set_errno(err));
}
long
lx_eventfd(uint_t val)
{
return (lx_eventfd2(val, 0));
}
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