diff options
Diffstat (limited to 'drivers/char/viocons.c')
| -rw-r--r-- | drivers/char/viocons.c | 1195 |
1 files changed, 1195 insertions, 0 deletions
diff --git a/drivers/char/viocons.c b/drivers/char/viocons.c new file mode 100644 index 00000000000..44f5fb4a46e --- /dev/null +++ b/drivers/char/viocons.c @@ -0,0 +1,1195 @@ +/* -*- linux-c -*- + * + * drivers/char/viocons.c + * + * iSeries Virtual Terminal + * + * Authors: Dave Boutcher <boutcher@us.ibm.com> + * Ryan Arnold <ryanarn@us.ibm.com> + * Colin Devilbiss <devilbis@us.ibm.com> + * Stephen Rothwell <sfr@au1.ibm.com> + * + * (C) Copyright 2000, 2001, 2002, 2003, 2004 IBM Corporation + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) anyu later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <linux/config.h> +#include <linux/version.h> +#include <linux/kernel.h> +#include <linux/proc_fs.h> +#include <linux/errno.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <linux/console.h> +#include <linux/module.h> +#include <asm/uaccess.h> +#include <linux/init.h> +#include <linux/wait.h> +#include <linux/spinlock.h> +#include <asm/ioctls.h> +#include <linux/kd.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/sysrq.h> + +#include <asm/iSeries/vio.h> + +#include <asm/iSeries/HvLpEvent.h> +#include <asm/iSeries/HvCallEvent.h> +#include <asm/iSeries/HvLpConfig.h> +#include <asm/iSeries/HvCall.h> + +#ifdef CONFIG_VT +#error You must turn off CONFIG_VT to use CONFIG_VIOCONS +#endif + +#define VIOTTY_MAGIC (0x0DCB) +#define VTTY_PORTS 10 + +#define VIOCONS_KERN_WARN KERN_WARNING "viocons: " +#define VIOCONS_KERN_INFO KERN_INFO "viocons: " + +static DEFINE_SPINLOCK(consolelock); +static DEFINE_SPINLOCK(consoleloglock); + +#ifdef CONFIG_MAGIC_SYSRQ +static int vio_sysrq_pressed; +extern int sysrq_enabled; +#endif + +/* + * The structure of the events that flow between us and OS/400. You can't + * mess with this unless the OS/400 side changes too + */ +struct viocharlpevent { + struct HvLpEvent event; + u32 reserved; + u16 version; + u16 subtype_result_code; + u8 virtual_device; + u8 len; + u8 data[VIOCHAR_MAX_DATA]; +}; + +#define VIOCHAR_WINDOW 10 +#define VIOCHAR_HIGHWATERMARK 3 + +enum viocharsubtype { + viocharopen = 0x0001, + viocharclose = 0x0002, + viochardata = 0x0003, + viocharack = 0x0004, + viocharconfig = 0x0005 +}; + +enum viochar_rc { + viochar_rc_ebusy = 1 +}; + +#define VIOCHAR_NUM_BUF 16 + +/* + * Our port information. We store a pointer to one entry in the + * tty_driver_data + */ +static struct port_info { + int magic; + struct tty_struct *tty; + HvLpIndex lp; + u8 vcons; + u64 seq; /* sequence number of last HV send */ + u64 ack; /* last ack from HV */ +/* + * When we get writes faster than we can send it to the partition, + * buffer the data here. Note that used is a bit map of used buffers. + * It had better have enough bits to hold VIOCHAR_NUM_BUF the bitops assume + * it is a multiple of unsigned long + */ + unsigned long used; + u8 *buffer[VIOCHAR_NUM_BUF]; + int bufferBytes[VIOCHAR_NUM_BUF]; + int curbuf; + int bufferOverflow; + int overflowMessage; +} port_info[VTTY_PORTS]; + +#define viochar_is_console(pi) ((pi) == &port_info[0]) +#define viochar_port(pi) ((pi) - &port_info[0]) + +static void initDataEvent(struct viocharlpevent *viochar, HvLpIndex lp); + +static struct tty_driver *viotty_driver; + +void hvlog(char *fmt, ...) +{ + int i; + unsigned long flags; + va_list args; + static char buf[256]; + + spin_lock_irqsave(&consoleloglock, flags); + va_start(args, fmt); + i = vscnprintf(buf, sizeof(buf) - 1, fmt, args); + va_end(args); + buf[i++] = '\r'; + HvCall_writeLogBuffer(buf, i); + spin_unlock_irqrestore(&consoleloglock, flags); +} + +void hvlogOutput(const char *buf, int count) +{ + unsigned long flags; + int begin; + int index; + static const char cr = '\r'; + + begin = 0; + spin_lock_irqsave(&consoleloglock, flags); + for (index = 0; index < count; index++) { + if (buf[index] == '\n') { + /* + * Start right after the last '\n' or at the zeroth + * array position and output the number of characters + * including the newline. + */ + HvCall_writeLogBuffer(&buf[begin], index - begin + 1); + begin = index + 1; + HvCall_writeLogBuffer(&cr, 1); + } + } + if ((index - begin) > 0) + HvCall_writeLogBuffer(&buf[begin], index - begin); + spin_unlock_irqrestore(&consoleloglock, flags); +} + +/* + * Make sure we're pointing to a valid port_info structure. Shamelessly + * plagerized from serial.c + */ +static inline int viotty_paranoia_check(struct port_info *pi, + char *name, const char *routine) +{ + static const char *bad_pi_addr = VIOCONS_KERN_WARN + "warning: bad address for port_info struct (%s) in %s\n"; + static const char *badmagic = VIOCONS_KERN_WARN + "warning: bad magic number for port_info struct (%s) in %s\n"; + + if ((pi < &port_info[0]) || (viochar_port(pi) > VTTY_PORTS)) { + printk(bad_pi_addr, name, routine); + return 1; + } + if (pi->magic != VIOTTY_MAGIC) { + printk(badmagic, name, routine); + return 1; + } + return 0; +} + +/* + * Add data to our pending-send buffers. + * + * NOTE: Don't use printk in here because it gets nastily recursive. + * hvlog can be used to log to the hypervisor buffer + */ +static int buffer_add(struct port_info *pi, const char *buf, size_t len) +{ + size_t bleft; + size_t curlen; + const char *curbuf; + int nextbuf; + + curbuf = buf; + bleft = len; + while (bleft > 0) { + /* + * If there is no space left in the current buffer, we have + * filled everything up, so return. If we filled the previous + * buffer we would already have moved to the next one. + */ + if (pi->bufferBytes[pi->curbuf] == VIOCHAR_MAX_DATA) { + hvlog ("\n\rviocons: No overflow buffer available for memcpy().\n"); + pi->bufferOverflow++; + pi->overflowMessage = 1; + break; + } + + /* + * Turn on the "used" bit for this buffer. If it's already on, + * that's fine. + */ + set_bit(pi->curbuf, &pi->used); + + /* + * See if this buffer has been allocated. If not, allocate it. + */ + if (pi->buffer[pi->curbuf] == NULL) { + pi->buffer[pi->curbuf] = + kmalloc(VIOCHAR_MAX_DATA, GFP_ATOMIC); + if (pi->buffer[pi->curbuf] == NULL) { + hvlog("\n\rviocons: kmalloc failed allocating spaces for buffer %d.", + pi->curbuf); + break; + } + } + + /* Figure out how much we can copy into this buffer. */ + if (bleft < (VIOCHAR_MAX_DATA - pi->bufferBytes[pi->curbuf])) + curlen = bleft; + else + curlen = VIOCHAR_MAX_DATA - pi->bufferBytes[pi->curbuf]; + + /* Copy the data into the buffer. */ + memcpy(pi->buffer[pi->curbuf] + pi->bufferBytes[pi->curbuf], + curbuf, curlen); + + pi->bufferBytes[pi->curbuf] += curlen; + curbuf += curlen; + bleft -= curlen; + + /* + * Now see if we've filled this buffer. If not then + * we'll try to use it again later. If we've filled it + * up then we'll advance the curbuf to the next in the + * circular queue. + */ + if (pi->bufferBytes[pi->curbuf] == VIOCHAR_MAX_DATA) { + nextbuf = (pi->curbuf + 1) % VIOCHAR_NUM_BUF; + /* + * Move to the next buffer if it hasn't been used yet + */ + if (test_bit(nextbuf, &pi->used) == 0) + pi->curbuf = nextbuf; + } + } + return len - bleft; +} + +/* + * Send pending data + * + * NOTE: Don't use printk in here because it gets nastily recursive. + * hvlog can be used to log to the hypervisor buffer + */ +static void send_buffers(struct port_info *pi) +{ + HvLpEvent_Rc hvrc; + int nextbuf; + struct viocharlpevent *viochar; + unsigned long flags; + + spin_lock_irqsave(&consolelock, flags); + + viochar = (struct viocharlpevent *) + vio_get_event_buffer(viomajorsubtype_chario); + + /* Make sure we got a buffer */ + if (viochar == NULL) { + hvlog("\n\rviocons: Can't get viochar buffer in sendBuffers()."); + spin_unlock_irqrestore(&consolelock, flags); + return; + } + + if (pi->used == 0) { + hvlog("\n\rviocons: in sendbuffers(), but no buffers used.\n"); + vio_free_event_buffer(viomajorsubtype_chario, viochar); + spin_unlock_irqrestore(&consolelock, flags); + return; + } + + /* + * curbuf points to the buffer we're filling. We want to + * start sending AFTER this one. + */ + nextbuf = (pi->curbuf + 1) % VIOCHAR_NUM_BUF; + + /* + * Loop until we find a buffer with the used bit on + */ + while (test_bit(nextbuf, &pi->used) == 0) + nextbuf = (nextbuf + 1) % VIOCHAR_NUM_BUF; + + initDataEvent(viochar, pi->lp); + + /* + * While we have buffers with data, and our send window + * is open, send them + */ + while ((test_bit(nextbuf, &pi->used)) && + ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) { + viochar->len = pi->bufferBytes[nextbuf]; + viochar->event.xCorrelationToken = pi->seq++; + viochar->event.xSizeMinus1 = + offsetof(struct viocharlpevent, data) + viochar->len; + + memcpy(viochar->data, pi->buffer[nextbuf], viochar->len); + + hvrc = HvCallEvent_signalLpEvent(&viochar->event); + if (hvrc) { + /* + * MUST unlock the spinlock before doing a printk + */ + vio_free_event_buffer(viomajorsubtype_chario, viochar); + spin_unlock_irqrestore(&consolelock, flags); + + printk(VIOCONS_KERN_WARN + "error sending event! return code %d\n", + (int)hvrc); + return; + } + + /* + * clear the used bit, zero the number of bytes in + * this buffer, and move to the next buffer + */ + clear_bit(nextbuf, &pi->used); + pi->bufferBytes[nextbuf] = 0; + nextbuf = (nextbuf + 1) % VIOCHAR_NUM_BUF; + } + + /* + * If we have emptied all the buffers, start at 0 again. + * this will re-use any allocated buffers + */ + if (pi->used == 0) { + pi->curbuf = 0; + + if (pi->overflowMessage) + pi->overflowMessage = 0; + + if (pi->tty) { + tty_wakeup(pi->tty); + } + } + + vio_free_event_buffer(viomajorsubtype_chario, viochar); + spin_unlock_irqrestore(&consolelock, flags); +} + +/* + * Our internal writer. Gets called both from the console device and + * the tty device. the tty pointer will be NULL if called from the console. + * Return total number of bytes "written". + * + * NOTE: Don't use printk in here because it gets nastily recursive. hvlog + * can be used to log to the hypervisor buffer + */ +static int internal_write(struct port_info *pi, const char *buf, size_t len) +{ + HvLpEvent_Rc hvrc; + size_t bleft; + size_t curlen; + const char *curbuf; + unsigned long flags; + struct viocharlpevent *viochar; + + /* + * Write to the hvlog of inbound data are now done prior to + * calling internal_write() since internal_write() is only called in + * the event that an lp event path is active, which isn't the case for + * logging attempts prior to console initialization. + * + * If there is already data queued for this port, send it prior to + * attempting to send any new data. + */ + if (pi->used) + send_buffers(pi); + + spin_lock_irqsave(&consolelock, flags); + + viochar = vio_get_event_buffer(viomajorsubtype_chario); + if (viochar == NULL) { + spin_unlock_irqrestore(&consolelock, flags); + hvlog("\n\rviocons: Can't get vio buffer in internal_write()."); + return -EAGAIN; + } + initDataEvent(viochar, pi->lp); + + curbuf = buf; + bleft = len; + + while ((bleft > 0) && (pi->used == 0) && + ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) { + if (bleft > VIOCHAR_MAX_DATA) + curlen = VIOCHAR_MAX_DATA; + else + curlen = bleft; + + viochar->event.xCorrelationToken = pi->seq++; + memcpy(viochar->data, curbuf, curlen); + viochar->len = curlen; + viochar->event.xSizeMinus1 = + offsetof(struct viocharlpevent, data) + curlen; + + hvrc = HvCallEvent_signalLpEvent(&viochar->event); + if (hvrc) { + hvlog("viocons: error sending event! %d\n", (int)hvrc); + goto out; + } + curbuf += curlen; + bleft -= curlen; + } + + /* If we didn't send it all, buffer as much of it as we can. */ + if (bleft > 0) + bleft -= buffer_add(pi, curbuf, bleft); +out: + vio_free_event_buffer(viomajorsubtype_chario, viochar); + spin_unlock_irqrestore(&consolelock, flags); + return len - bleft; +} + +static struct port_info *get_port_data(struct tty_struct *tty) +{ + unsigned long flags; + struct port_info *pi; + + spin_lock_irqsave(&consolelock, flags); + if (tty) { + pi = (struct port_info *)tty->driver_data; + if (!pi || viotty_paranoia_check(pi, tty->name, + "get_port_data")) { + pi = NULL; + } + } else + /* + * If this is the console device, use the lp from + * the first port entry + */ + pi = &port_info[0]; + spin_unlock_irqrestore(&consolelock, flags); + return pi; +} + +/* + * Initialize the common fields in a charLpEvent + */ +static void initDataEvent(struct viocharlpevent *viochar, HvLpIndex lp) +{ + memset(viochar, 0, sizeof(struct viocharlpevent)); + + viochar->event.xFlags.xValid = 1; + viochar->event.xFlags.xFunction = HvLpEvent_Function_Int; + viochar->event.xFlags.xAckInd = HvLpEvent_AckInd_NoAck; + viochar->event.xFlags.xAckType = HvLpEvent_AckType_DeferredAck; + viochar->event.xType = HvLpEvent_Type_VirtualIo; + viochar->event.xSubtype = viomajorsubtype_chario | viochardata; + viochar->event.xSourceLp = HvLpConfig_getLpIndex(); + viochar->event.xTargetLp = lp; + viochar->event.xSizeMinus1 = sizeof(struct viocharlpevent); + viochar->event.xSourceInstanceId = viopath_sourceinst(lp); + viochar->event.xTargetInstanceId = viopath_targetinst(lp); +} + +/* + * early console device write + */ +static void viocons_write_early(struct console *co, const char *s, unsigned count) +{ + hvlogOutput(s, count); +} + +/* + * console device write + */ +static void viocons_write(struct console *co, const char *s, unsigned count) +{ + int index; + int begin; + struct port_info *pi; + + static const char cr = '\r'; + + /* + * Check port data first because the target LP might be valid but + * simply not active, in which case we want to hvlog the output. + */ + pi = get_port_data(NULL); + if (pi == NULL) { + hvlog("\n\rviocons_write: unable to get port data."); + return; + } + + hvlogOutput(s, count); + + if (!viopath_isactive(pi->lp)) + return; + + /* + * Any newline character found will cause a + * carriage return character to be emitted as well. + */ + begin = 0; + for (index = 0; index < count; index++) { + if (s[index] == '\n') { + /* + * Newline found. Print everything up to and + * including the newline + */ + internal_write(pi, &s[begin], index - begin + 1); + begin = index + 1; + /* Emit a carriage return as well */ + internal_write(pi, &cr, 1); + } + } + + /* If any characters left to write, write them now */ + if ((index - begin) > 0) + internal_write(pi, &s[begin], index - begin); +} + +/* + * Work out the device associate with this console + */ +static struct tty_driver *viocons_device(struct console *c, int *index) +{ + *index = c->index; + return viotty_driver; +} + +/* + * console device I/O methods + */ +static struct console viocons_early = { + .name = "viocons", + .write = viocons_write_early, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +static struct console viocons = { + .name = "viocons", + .write = viocons_write, + .device = viocons_device, + .flags = CON_PRINTBUFFER, + .index = -1, +}; + +/* + * TTY Open method + */ +static int viotty_open(struct tty_struct *tty, struct file *filp) +{ + int port; + unsigned long flags; + struct port_info *pi; + + port = tty->index; + + if ((port < 0) || (port >= VTTY_PORTS)) + return -ENODEV; + + spin_lock_irqsave(&consolelock, flags); + + pi = &port_info[port]; + /* If some other TTY is already connected here, reject the open */ + if ((pi->tty) && (pi->tty != tty)) { + spin_unlock_irqrestore(&consolelock, flags); + printk(VIOCONS_KERN_WARN + "attempt to open device twice from different ttys\n"); + return -EBUSY; + } + tty->driver_data = pi; + pi->tty = tty; + spin_unlock_irqrestore(&consolelock, flags); + + return 0; +} + +/* + * TTY Close method + */ +static void viotty_close(struct tty_struct *tty, struct file *filp) +{ + unsigned long flags; + struct port_info *pi; + + spin_lock_irqsave(&consolelock, flags); + pi = (struct port_info *)tty->driver_data; + + if (!pi || viotty_paranoia_check(pi, tty->name, "viotty_close")) { + spin_unlock_irqrestore(&consolelock, flags); + return; + } + if (tty->count == 1) + pi->tty = NULL; + spin_unlock_irqrestore(&consolelock, flags); +} + +/* + * TTY Write method + */ +static int viotty_write(struct tty_struct *tty, const unsigned char *buf, + int count) +{ + struct port_info *pi; + + pi = get_port_data(tty); + if (pi == NULL) { + hvlog("\n\rviotty_write: no port data."); + return -ENODEV; + } + + if (viochar_is_console(pi)) + hvlogOutput(buf, count); + + /* + * If the path to this LP is closed, don't bother doing anything more. + * just dump the data on the floor and return count. For some reason + * some user level programs will attempt to probe available tty's and + * they'll attempt a viotty_write on an invalid port which maps to an + * invalid target lp. If this is the case then ignore the + * viotty_write call and, since the viopath isn't active to this + * partition, return count. + */ + if (!viopath_isactive(pi->lp)) + return count; + + return internal_write(pi, buf, count); +} + +/* + * TTY put_char method + */ +static void viotty_put_char(struct tty_struct *tty, unsigned char ch) +{ + struct port_info *pi; + + pi = get_port_data(tty); + if (pi == NULL) + return; + + /* This will append '\r' as well if the char is '\n' */ + if (viochar_is_console(pi)) + hvlogOutput(&ch, 1); + + if (viopath_isactive(pi->lp)) + internal_write(pi, &ch, 1); +} + +/* + * TTY write_room method + */ +static int viotty_write_room(struct tty_struct *tty) +{ + int i; + int room = 0; + struct port_info *pi; + unsigned long flags; + + spin_lock_irqsave(&consolelock, flags); + pi = (struct port_info *)tty->driver_data; + if (!pi || viotty_paranoia_check(pi, tty->name, "viotty_write_room")) { + spin_unlock_irqrestore(&consolelock, flags); + return 0; + } + + /* If no buffers are used, return the max size. */ + if (pi->used == 0) { + spin_unlock_irqrestore(&consolelock, flags); + return VIOCHAR_MAX_DATA * VIOCHAR_NUM_BUF; + } + + /* + * We retain the spinlock because we want to get an accurate + * count and it can change on us between each operation if we + * don't hold the spinlock. + */ + for (i = 0; ((i < VIOCHAR_NUM_BUF) && (room < VIOCHAR_MAX_DATA)); i++) + room += (VIOCHAR_MAX_DATA - pi->bufferBytes[i]); + spin_unlock_irqrestore(&consolelock, flags); + + if (room > VIOCHAR_MAX_DATA) + room = VIOCHAR_MAX_DATA; + return room; +} + +/* + * TTY chars_in_buffer method + */ +static int viotty_chars_in_buffer(struct tty_struct *tty) +{ + return 0; +} + +static int viotty_ioctl(struct tty_struct *tty, struct file *file, + unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + /* + * the ioctls below read/set the flags usually shown in the leds + * don't use them - they will go away without warning + */ + case KDGETLED: + case KDGKBLED: + return put_user(0, (char *)arg); + + case KDSKBLED: + return 0; + } + + return n_tty_ioctl(tty, file, cmd, arg); +} + +/* + * Handle an open charLpEvent. Could be either interrupt or ack + */ +static void vioHandleOpenEvent(struct HvLpEvent *event) +{ + unsigned long flags; + struct viocharlpevent *cevent = (struct viocharlpevent *)event; + u8 port = cevent->virtual_device; + struct port_info *pi; + int reject = 0; + + if (event->xFlags.xFunction == HvLpEvent_Function_Ack) { + if (port >= VTTY_PORTS) + return; + + spin_lock_irqsave(&consolelock, flags); + /* Got the lock, don't cause console output */ + + pi = &port_info[port]; + if (event->xRc == HvLpEvent_Rc_Good) { + pi->seq = pi->ack = 0; + /* + * This line allows connections from the primary + * partition but once one is connected from the + * primary partition nothing short of a reboot + * of linux will allow access from the hosting + * partition again without a required iSeries fix. + */ + pi->lp = event->xTargetLp; + } + + spin_unlock_irqrestore(&consolelock, flags); + if (event->xRc != HvLpEvent_Rc_Good) + printk(VIOCONS_KERN_WARN + "handle_open_event: event->xRc == (%d).\n", + event->xRc); + + if (event->xCorrelationToken != 0) { + atomic_t *aptr= (atomic_t *)event->xCorrelationToken; + atomic_set(aptr, 1); + } else + printk(VIOCONS_KERN_WARN + "weird...got open ack without atomic\n"); + return; + } + + /* This had better require an ack, otherwise complain */ + if (event->xFlags.xAckInd != HvLpEvent_AckInd_DoAck) { + printk(VIOCONS_KERN_WARN "viocharopen without ack bit!\n"); + return; + } + + spin_lock_irqsave(&consolelock, flags); + /* Got the lock, don't cause console output */ + + /* Make sure this is a good virtual tty */ + if (port >= VTTY_PORTS) { + event->xRc = HvLpEvent_Rc_SubtypeError; + cevent->subtype_result_code = viorc_openRejected; + /* + * Flag state here since we can't printk while holding + * a spinlock. + */ + reject = 1; + } else { + pi = &port_info[port]; + if ((pi->lp != HvLpIndexInvalid) && + (pi->lp != event->xSourceLp)) { + /* + * If this is tty is already connected to a different + * partition, fail. + */ + event->xRc = HvLpEvent_Rc_SubtypeError; + cevent->subtype_result_code = viorc_openRejected; + reject = 2; + } else { + pi->lp = event->xSourceLp; + event->xRc = HvLpEvent_Rc_Good; + cevent->subtype_result_code = viorc_good; + pi->seq = pi->ack = 0; + reject = 0; + } + } + + spin_unlock_irqrestore(&consolelock, flags); + + if (reject == 1) + printk(VIOCONS_KERN_WARN "open rejected: bad virtual tty.\n"); + else if (reject == 2) + printk(VIOCONS_KERN_WARN + "open rejected: console in exclusive use by another partition.\n"); + + /* Return the acknowledgement */ + HvCallEvent_ackLpEvent(event); +} + +/* + * Handle a close charLpEvent. This should ONLY be an Interrupt because the + * virtual console should never actually issue a close event to the hypervisor + * because the virtual console never goes away. A close event coming from the + * hypervisor simply means that there are no client consoles connected to the + * virtual console. + * + * Regardless of the number of connections masqueraded on the other side of + * the hypervisor ONLY ONE close event should be called to accompany the ONE + * open event that is called. The close event should ONLY be called when NO + * MORE connections (masqueraded or not) exist on the other side of the + * hypervisor. + */ +static void vioHandleCloseEvent(struct HvLpEvent *event) +{ + unsigned long flags; + struct viocharlpevent *cevent = (struct viocharlpevent *)event; + u8 port = cevent->virtual_device; + + if (event->xFlags.xFunction == HvLpEvent_Function_Int) { + if (port >= VTTY_PORTS) { + printk(VIOCONS_KERN_WARN + "close message from invalid virtual device.\n"); + return; + } + + /* For closes, just mark the console partition invalid */ + spin_lock_irqsave(&consolelock, flags); + /* Got the lock, don't cause console output */ + + if (port_info[port].lp == event->xSourceLp) + port_info[port].lp = HvLpIndexInvalid; + + spin_unlock_irqrestore(&consolelock, flags); + printk(VIOCONS_KERN_INFO "close from %d\n", event->xSourceLp); + } else + printk(VIOCONS_KERN_WARN + "got unexpected close acknowlegement\n"); +} + +/* + * Handle a config charLpEvent. Could be either interrupt or ack + */ +static void vioHandleConfig(struct HvLpEvent *event) +{ + struct viocharlpevent *cevent = (struct viocharlpevent *)event; + + HvCall_writeLogBuffer(cevent->data, cevent->len); + + if (cevent->data[0] == 0x01) + printk(VIOCONS_KERN_INFO "window resized to %d: %d: %d: %d\n", + cevent->data[1], cevent->data[2], + cevent->data[3], cevent->data[4]); + else + printk(VIOCONS_KERN_WARN "unknown config event\n"); +} + +/* + * Handle a data charLpEvent. + */ +static void vioHandleData(struct HvLpEvent *event) +{ + struct tty_struct *tty; + unsigned long flags; + struct viocharlpevent *cevent = (struct viocharlpevent *)event; + struct port_info *pi; + int index; + u8 port = cevent->virtual_device; + + if (port >= VTTY_PORTS) { + printk(VIOCONS_KERN_WARN "data on invalid virtual device %d\n", + port); + return; + } + + /* + * Hold the spinlock so that we don't take an interrupt that + * changes tty between the time we fetch the port_info + * pointer and the time we paranoia check. + */ + spin_lock_irqsave(&consolelock, flags); + pi = &port_info[port]; + + /* + * Change 05/01/2003 - Ryan Arnold: If a partition other than + * the current exclusive partition tries to send us data + * events then just drop them on the floor because we don't + * want his stinking data. He isn't authorized to receive + * data because he wasn't the first one to get the console, + * therefore he shouldn't be allowed to send data either. + * This will work without an iSeries fix. + */ + if (pi->lp != event->xSourceLp) { + spin_unlock_irqrestore(&consolelock, flags); + return; + } + + tty = pi->tty; + if (tty == NULL) { + spin_unlock_irqrestore(&consolelock, flags); + printk(VIOCONS_KERN_WARN "no tty for virtual device %d\n", + port); + return; + } + + if (tty->magic != TTY_MAGIC) { + spin_unlock_irqrestore(&consolelock, flags); + printk(VIOCONS_KERN_WARN "tty bad magic\n"); + return; + } + + /* + * Just to be paranoid, make sure the tty points back to this port + */ + pi = (struct port_info *)tty->driver_data; + if (!pi || viotty_paranoia_check(pi, tty->name, "vioHandleData")) { + spin_unlock_irqrestore(&consolelock, flags); + return; + } + spin_unlock_irqrestore(&consolelock, flags); + + /* + * Change 07/21/2003 - Ryan Arnold: functionality added to + * support sysrq utilizing ^O as the sysrq key. The sysrq + * functionality will only work if built into the kernel and + * then only if sysrq is enabled through the proc filesystem. + */ + for (index = 0; index < cevent->len; index++) { +#ifdef CONFIG_MAGIC_SYSRQ + if (sysrq_enabled) { + /* 0x0f is the ascii character for ^O */ + if (cevent->data[index] == '\x0f') { + vio_sysrq_pressed = 1; + /* + * continue because we don't want to add + * the sysrq key into the data string. + */ + continue; + } else if (vio_sysrq_pressed) { + handle_sysrq(cevent->data[index], NULL, tty); + vio_sysrq_pressed = 0; + /* + * continue because we don't want to add + * the sysrq sequence into the data string. + */ + continue; + } + } +#endif + /* + * The sysrq sequence isn't included in this check if + * sysrq is enabled and compiled into the kernel because + * the sequence will never get inserted into the buffer. + * Don't attempt to copy more data into the buffer than we + * have room for because it would fail without indication. + */ + if ((tty->flip.count + 1) > TTY_FLIPBUF_SIZE) { + printk(VIOCONS_KERN_WARN "input buffer overflow!\n"); + break; + } + tty_insert_flip_char(tty, cevent->data[index], TTY_NORMAL); + } + + /* if cevent->len == 0 then no data was added to the buffer and flip.count == 0 */ + if (tty->flip.count) + /* The next call resets flip.count when the data is flushed. */ + tty_flip_buffer_push(tty); +} + +/* + * Handle an ack charLpEvent. + */ +static void vioHandleAck(struct HvLpEvent *event) +{ + struct viocharlpevent *cevent = (struct viocharlpevent *)event; + unsigned long flags; + u8 port = cevent->virtual_device; + + if (port >= VTTY_PORTS) { + printk(VIOCONS_KERN_WARN "data on invalid virtual device\n"); + return; + } + + spin_lock_irqsave(&consolelock, flags); + port_info[port].ack = event->xCorrelationToken; + spin_unlock_irqrestore(&consolelock, flags); + + if (port_info[port].used) + send_buffers(&port_info[port]); +} + +/* + * Handle charLpEvents and route to the appropriate routine + */ +static void vioHandleCharEvent(struct HvLpEvent *event) +{ + int charminor; + + if (event == NULL) + return; + + charminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK; + switch (charminor) { + case viocharopen: + vioHandleOpenEvent(event); + break; + case viocharclose: + vioHandleCloseEvent(event); + break; + case viochardata: + vioHandleData(event); + break; + case viocharack: + vioHandleAck(event); + break; + case viocharconfig: + vioHandleConfig(event); + break; + default: + if ((event->xFlags.xFunction == HvLpEvent_Function_Int) && + (event->xFlags.xAckInd == HvLpEvent_AckInd_DoAck)) { + event->xRc = HvLpEvent_Rc_InvalidSubtype; + HvCallEvent_ackLpEvent(event); + } + } +} + +/* + * Send an open event + */ +static int send_open(HvLpIndex remoteLp, void *sem) +{ + return HvCallEvent_signalLpEventFast(remoteLp, + HvLpEvent_Type_VirtualIo, + viomajorsubtype_chario | viocharopen, + HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck, + viopath_sourceinst(remoteLp), + viopath_targetinst(remoteLp), + (u64)(unsigned long)sem, VIOVERSION << 16, + 0, 0, 0, 0); +} + +static struct tty_operations serial_ops = { + .open = viotty_open, + .close = viotty_close, + .write = viotty_write, + .put_char = viotty_put_char, + .write_room = viotty_write_room, + .chars_in_buffer = viotty_chars_in_buffer, + .ioctl = viotty_ioctl, +}; + +static int __init viocons_init2(void) +{ + atomic_t wait_flag; + int rc; + + /* +2 for fudge */ + rc = viopath_open(HvLpConfig_getPrimaryLpIndex(), + viomajorsubtype_chario, VIOCHAR_WINDOW + 2); + if (rc) + printk(VIOCONS_KERN_WARN "error opening to primary %d\n", rc); + + if (viopath_hostLp == HvLpIndexInvalid) + vio_set_hostlp(); + + /* + * And if the primary is not the same as the hosting LP, open to the + * hosting lp + */ + if ((viopath_hostLp != HvLpIndexInvalid) && + (viopath_hostLp != HvLpConfig_getPrimaryLpIndex())) { + printk(VIOCONS_KERN_INFO "open path to hosting (%d)\n", + viopath_hostLp); + rc = viopath_open(viopath_hostLp, viomajorsubtype_chario, + VIOCHAR_WINDOW + 2); /* +2 for fudge */ + if (rc) + printk(VIOCONS_KERN_WARN + "error opening to partition %d: %d\n", + viopath_hostLp, rc); + } + + if (vio_setHandler(viomajorsubtype_chario, vioHandleCharEvent) < 0) + printk(VIOCONS_KERN_WARN + "error seting handler for console events!\n"); + + /* + * First, try to open the console to the hosting lp. + * Wait on a semaphore for the response. + */ + atomic_set(&wait_flag, 0); + if ((viopath_isactive(viopath_hostLp)) && + (send_open(viopath_hostLp, (void *)&wait_flag) == 0)) { + printk(VIOCONS_KERN_INFO "hosting partition %d\n", + viopath_hostLp); + while (atomic_read(&wait_flag) == 0) + mb(); + atomic_set(&wait_flag, 0); + } + + /* + * If we don't have an active console, try the primary + */ + if ((!viopath_isactive(port_info[0].lp)) && + (viopath_isactive(HvLpConfig_getPrimaryLpIndex())) && + (send_open(HvLpConfig_getPrimaryLpIndex(), (void *)&wait_flag) + == 0)) { + printk(VIOCONS_KERN_INFO "opening console to primary partition\n"); + while (atomic_read(&wait_flag) == 0) + mb(); + } + + /* Initialize the tty_driver structure */ + viotty_driver = alloc_tty_driver(VTTY_PORTS); + viotty_driver->owner = THIS_MODULE; + viotty_driver->driver_name = "vioconsole"; + viotty_driver->devfs_name = "vcs/"; + viotty_driver->name = "tty"; + viotty_driver->name_base = 1; + viotty_driver->major = TTY_MAJOR; + viotty_driver->minor_start = 1; + viotty_driver->type = TTY_DRIVER_TYPE_CONSOLE; + viotty_driver->subtype = 1; + viotty_driver->init_termios = tty_std_termios; + viotty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS; + tty_set_operations(viotty_driver, &serial_ops); + + if (tty_register_driver(viotty_driver)) { + printk(VIOCONS_KERN_WARN "couldn't register console driver\n"); + put_tty_driver(viotty_driver); + viotty_driver = NULL; + } + + unregister_console(&viocons_early); + register_console(&viocons); + + return 0; +} + +static int __init viocons_init(void) +{ + int i; + + printk(VIOCONS_KERN_INFO "registering console\n"); + for (i = 0; i < VTTY_PORTS; i++) { + port_info[i].lp = HvLpIndexInvalid; + port_info[i].magic = VIOTTY_MAGIC; + } + HvCall_setLogBufferFormatAndCodepage(HvCall_LogBuffer_ASCII, 437); + register_console(&viocons_early); + return 0; +} + +console_initcall(viocons_init); +module_init(viocons_init2); |