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author | ed <ed@FreeBSD.org> | 2008-08-20 08:31:58 +0000 |
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committer | ed <ed@FreeBSD.org> | 2008-08-20 08:31:58 +0000 |
commit | cc3116a9380fe32a751b584f3d8083698ccfba15 (patch) | |
tree | bd0c08a66997254385160ce71ea32029b99f99f9 /sys/sun4v | |
parent | b49301b5cd9ff43a7af0bd9054d9d1a328c0d212 (diff) | |
download | FreeBSD-src-cc3116a9380fe32a751b584f3d8083698ccfba15.zip FreeBSD-src-cc3116a9380fe32a751b584f3d8083698ccfba15.tar.gz |
Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
Diffstat (limited to 'sys/sun4v')
-rw-r--r-- | sys/sun4v/conf/GENERIC | 2 | ||||
-rw-r--r-- | sys/sun4v/sun4v/hvcons.c | 162 |
2 files changed, 50 insertions, 114 deletions
diff --git a/sys/sun4v/conf/GENERIC b/sys/sun4v/conf/GENERIC index 4e93a06..1a3f695 100644 --- a/sys/sun4v/conf/GENERIC +++ b/sys/sun4v/conf/GENERIC @@ -170,7 +170,7 @@ device loop # Network loopback device random # Entropy device device ether # Ethernet support device tun # Packet tunnel. -device pty # Pseudo-ttys (telnet etc) +device pty # BSD-style compatibility pseudo ttys device md # Memory "disks" device gif # IPv6 and IPv4 tunneling device faith # IPv6-to-IPv4 relaying (translation) diff --git a/sys/sun4v/sun4v/hvcons.c b/sys/sun4v/sun4v/hvcons.c index 0217a85..314d15c 100644 --- a/sys/sun4v/sun4v/hvcons.c +++ b/sys/sun4v/sun4v/hvcons.c @@ -53,16 +53,14 @@ __FBSDID("$FreeBSD$"); #define HVCN_POLL_FREQ 10 - -static d_open_t hvcn_open; -static d_close_t hvcn_close; - -static struct cdevsw hvcn_cdevsw = { - .d_version = D_VERSION, - .d_open = hvcn_open, - .d_close = hvcn_close, - .d_name = "hvcn", - .d_flags = D_TTY | D_NEEDGIANT, +static tsw_open_t hvcn_open; +static tsw_outwakeup_t hvcn_outwakeup; +static tsw_close_t hvcn_close; + +static struct ttydevsw hvcn_class = { + .tsw_open = hvcn_open, + .tsw_outwakeup = hvcn_outwakeup, + .tsw_close = hvcn_close, }; #define PCBURST 16 @@ -81,9 +79,6 @@ static struct callout_handle hvcn_timeouthandle static int alt_break_state; #endif -static void hvcn_tty_start(struct tty *); -static int hvcn_tty_param(struct tty *, struct termios *); -static void hvcn_tty_stop(struct tty *, int); static void hvcn_timeout(void *); static cn_probe_t hvcn_cnprobe; @@ -113,67 +108,27 @@ hv_cnputs(char *p) } static int -hvcn_open(struct cdev *dev, int flag, int mode, struct thread *td) +hvcn_open(struct tty *tp) { - struct tty *tp; - int error, setuptimeout; - - setuptimeout = 0; - - if (dev->si_tty == NULL) { - hvcn_tp = ttyalloc(); - dev->si_tty = hvcn_tp; - hvcn_tp->t_dev = dev; - } - tp = dev->si_tty; - - tp->t_oproc = hvcn_tty_start; - tp->t_param = hvcn_tty_param; - tp->t_stop = hvcn_tty_stop; - if ((tp->t_state & TS_ISOPEN) == 0) { - tp->t_state |= TS_CARR_ON; - ttyconsolemode(tp, 0); - - setuptimeout = 1; - } else if ((tp->t_state & TS_XCLUDE) && priv_check(td, - PRIV_TTY_EXCLUSIVE)) { - return (EBUSY); - } - - error = ttyld_open(tp, dev); -#if defined(SIMULATOR) || 1 - if (error == 0 && setuptimeout) { - int polltime; + /* + * Set up timeout to trigger fake interrupts to transmit + * trailing data. + */ + polltime = hz / HVCN_POLL_FREQ; + if (polltime < 1) + polltime = 1; + hvcn_timeouthandle = timeout(hvcn_timeout, tp, polltime); - polltime = hz / HVCN_POLL_FREQ; - if (polltime < 1) { - polltime = 1; - } + buflen = 0; - hvcn_timeouthandle = timeout(hvcn_timeout, tp, polltime); - } -#endif - return (error); + return (0); } -static int -hvcn_close(struct cdev *dev, int flag, int mode, struct thread *td) +static void +hvcn_close(struct tty *tp) { - int unit; - struct tty *tp; - - unit = minor(dev); - tp = dev->si_tty; - - if (unit != 0) - return (ENXIO); - untimeout(hvcn_timeout, tp, hvcn_timeouthandle); - ttyld_close(tp, flag); - tty_close(tp); - - return (0); } static void @@ -210,7 +165,8 @@ done: static void hvcn_cninit(struct consdev *cp) { - sprintf(cp->cn_name, "hvcn"); + + strcpy(cp->cn_name, "hvcn"); } static int @@ -295,64 +251,43 @@ hvcn_cnputc(struct consdev *cp, int c) } while (error == H_EWOULDBLOCK); } -static int -hvcn_tty_param(struct tty *tp, struct termios *t) -{ - tp->t_ispeed = t->c_ispeed; - tp->t_ospeed = t->c_ospeed; - tp->t_cflag = t->c_cflag; - - return (0); -} - static void -hvcn_tty_start(struct tty *tp) +hvcn_outwakeup(struct tty *tp) { - if (!(tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP))) { - tp->t_state |= TS_BUSY; + for (;;) { + /* Refill the input buffer. */ + if (buflen == 0) { + buflen = ttydisc_getc(tp, buf, PCBURST); + bufindex = 0; + } - do { - if (buflen == 0) { - buflen = q_to_b(&tp->t_outq, buf, PCBURST); - bufindex = 0; - } - while (buflen) { - if (hv_cons_putchar(buf[bufindex]) == H_EWOULDBLOCK) - goto done; - bufindex++; - buflen--; - } - } while (tp->t_outq.c_cc != 0); - done: - tp->t_state &= ~TS_BUSY; - ttwwakeup(tp); + /* Transmit the input buffer. */ + while (buflen) { + if (hv_cons_putchar(buf[bufindex]) == H_EWOULDBLOCK) + return; + bufindex++; + buflen--; + } } } static void -hvcn_tty_stop(struct tty *tp, int flag) -{ - if ((tp->t_state & TS_BUSY) && !(tp->t_state & TS_TTSTOP)) - tp->t_state |= TS_FLUSH; - - -} - -static void hvcn_intr(void *v) { - struct tty *tp; + struct tty *tp = v; int c; - tp = (struct tty *)v; + tty_lock(tp); + /* Receive data. */ while ((c = hvcn_cncheckc(NULL)) != -1) - if (tp->t_state & TS_ISOPEN) - ttyld_rint(tp, c); + ttydisc_rint(tp, c, 0); + ttydisc_rint_done(tp); - if (tp->t_outq.c_cc != 0 || buflen != 0) - hvcn_tty_start(tp); + /* Transmit trailing data. */ + hvcn_outwakeup(tp); + tty_unlock(tp); } static void @@ -381,7 +316,7 @@ static int hvcn_dev_attach(device_t dev) { - struct cdev *cdev; + struct tty *tp; int error, rid; /* belongs in attach - but attach is getting called multiple times @@ -392,8 +327,9 @@ hvcn_dev_attach(device_t dev) hvcn_consdev.cn_name[0] == '\0') return (ENXIO); - cdev = make_dev(&hvcn_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "ttyv%r", 1); - make_dev_alias(cdev, "hvcn"); + tp = tty_alloc(&hvcn_class, NULL, NULL); + tty_makedev(tp, NULL, "v%r", 1); + tty_makealias(tp, "hvcn"); rid = 0; |