diff options
Diffstat (limited to 'drivers/char/vt_ioctl.c')
-rw-r--r-- | drivers/char/vt_ioctl.c | 482 |
1 files changed, 431 insertions, 51 deletions
diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c index 95189f288f8..29c651ab0d7 100644 --- a/drivers/char/vt_ioctl.c +++ b/drivers/char/vt_ioctl.c @@ -16,6 +16,8 @@ #include <linux/tty.h> #include <linux/timer.h> #include <linux/kernel.h> +#include <linux/compat.h> +#include <linux/module.h> #include <linux/kd.h> #include <linux/vt.h> #include <linux/string.h> @@ -62,6 +64,133 @@ extern struct tty_driver *console_driver; static void complete_change_console(struct vc_data *vc); /* + * User space VT_EVENT handlers + */ + +struct vt_event_wait { + struct list_head list; + struct vt_event event; + int done; +}; + +static LIST_HEAD(vt_events); +static DEFINE_SPINLOCK(vt_event_lock); +static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue); + +/** + * vt_event_post + * @event: the event that occurred + * @old: old console + * @new: new console + * + * Post an VT event to interested VT handlers + */ + +void vt_event_post(unsigned int event, unsigned int old, unsigned int new) +{ + struct list_head *pos, *head; + unsigned long flags; + int wake = 0; + + spin_lock_irqsave(&vt_event_lock, flags); + head = &vt_events; + + list_for_each(pos, head) { + struct vt_event_wait *ve = list_entry(pos, + struct vt_event_wait, list); + if (!(ve->event.event & event)) + continue; + ve->event.event = event; + /* kernel view is consoles 0..n-1, user space view is + console 1..n with 0 meaning current, so we must bias */ + ve->event.old = old + 1; + ve->event.new = new + 1; + wake = 1; + ve->done = 1; + } + spin_unlock_irqrestore(&vt_event_lock, flags); + if (wake) + wake_up_interruptible(&vt_event_waitqueue); +} + +/** + * vt_event_wait - wait for an event + * @vw: our event + * + * Waits for an event to occur which completes our vt_event_wait + * structure. On return the structure has wv->done set to 1 for success + * or 0 if some event such as a signal ended the wait. + */ + +static void vt_event_wait(struct vt_event_wait *vw) +{ + unsigned long flags; + /* Prepare the event */ + INIT_LIST_HEAD(&vw->list); + vw->done = 0; + /* Queue our event */ + spin_lock_irqsave(&vt_event_lock, flags); + list_add(&vw->list, &vt_events); + spin_unlock_irqrestore(&vt_event_lock, flags); + /* Wait for it to pass */ + wait_event_interruptible(vt_event_waitqueue, vw->done); + /* Dequeue it */ + spin_lock_irqsave(&vt_event_lock, flags); + list_del(&vw->list); + spin_unlock_irqrestore(&vt_event_lock, flags); +} + +/** + * vt_event_wait_ioctl - event ioctl handler + * @arg: argument to ioctl + * + * Implement the VT_WAITEVENT ioctl using the VT event interface + */ + +static int vt_event_wait_ioctl(struct vt_event __user *event) +{ + struct vt_event_wait vw; + + if (copy_from_user(&vw.event, event, sizeof(struct vt_event))) + return -EFAULT; + /* Highest supported event for now */ + if (vw.event.event & ~VT_MAX_EVENT) + return -EINVAL; + + vt_event_wait(&vw); + /* If it occurred report it */ + if (vw.done) { + if (copy_to_user(event, &vw.event, sizeof(struct vt_event))) + return -EFAULT; + return 0; + } + return -EINTR; +} + +/** + * vt_waitactive - active console wait + * @event: event code + * @n: new console + * + * Helper for event waits. Used to implement the legacy + * event waiting ioctls in terms of events + */ + +int vt_waitactive(int n) +{ + struct vt_event_wait vw; + do { + if (n == fg_console + 1) + break; + vw.event.event = VT_EVENT_SWITCH; + vt_event_wait(&vw); + if (vw.done == 0) + return -EINTR; + } while (vw.event.new != n); + return 0; +} + +/* * these are the valid i/o ports we're allowed to change. they map all the * video ports */ @@ -360,6 +489,8 @@ do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_ return 0; } + + /* * We handle the console-specific ioctl's here. We allow the * capability to modify any console, not just the fg_console. @@ -842,6 +973,41 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, } break; + case VT_SETACTIVATE: + { + struct vt_setactivate vsa; + + if (!perm) + goto eperm; + + if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg, + sizeof(struct vt_setactivate))) + return -EFAULT; + if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES) + ret = -ENXIO; + else { + vsa.console--; + acquire_console_sem(); + ret = vc_allocate(vsa.console); + if (ret == 0) { + struct vc_data *nvc; + /* This is safe providing we don't drop the + console sem between vc_allocate and + finishing referencing nvc */ + nvc = vc_cons[vsa.console].d; + nvc->vt_mode = vsa.mode; + nvc->vt_mode.frsig = 0; + put_pid(nvc->vt_pid); + nvc->vt_pid = get_pid(task_pid(current)); + } + release_console_sem(); + if (ret) + break; + /* Commence switch and lock */ + set_console(arg); + } + } + /* * wait until the specified VT has been activated */ @@ -851,7 +1017,7 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, if (arg == 0 || arg > MAX_NR_CONSOLES) ret = -ENXIO; else - ret = vt_waitactive(arg - 1); + ret = vt_waitactive(arg); break; /* @@ -1159,6 +1325,9 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, ret = put_user(vc->vc_hi_font_mask, (unsigned short __user *)arg); break; + case VT_WAITEVENT: + ret = vt_event_wait_ioctl((struct vt_event __user *)arg); + break; default: ret = -ENOIOCTLCMD; } @@ -1170,54 +1339,6 @@ eperm: goto out; } -/* - * Sometimes we want to wait until a particular VT has been activated. We - * do it in a very simple manner. Everybody waits on a single queue and - * get woken up at once. Those that are satisfied go on with their business, - * while those not ready go back to sleep. Seems overkill to add a wait - * to each vt just for this - usually this does nothing! - */ -static DECLARE_WAIT_QUEUE_HEAD(vt_activate_queue); - -/* - * Sleeps until a vt is activated, or the task is interrupted. Returns - * 0 if activation, -EINTR if interrupted by a signal handler. - */ -int vt_waitactive(int vt) -{ - int retval; - DECLARE_WAITQUEUE(wait, current); - - add_wait_queue(&vt_activate_queue, &wait); - for (;;) { - retval = 0; - - /* - * Synchronize with redraw_screen(). By acquiring the console - * semaphore we make sure that the console switch is completed - * before we return. If we didn't wait for the semaphore, we - * could return at a point where fg_console has already been - * updated, but the console switch hasn't been completed. - */ - acquire_console_sem(); - set_current_state(TASK_INTERRUPTIBLE); - if (vt == fg_console) { - release_console_sem(); - break; - } - release_console_sem(); - retval = -ERESTARTNOHAND; - if (signal_pending(current)) - break; - schedule(); - } - remove_wait_queue(&vt_activate_queue, &wait); - __set_current_state(TASK_RUNNING); - return retval; -} - -#define vt_wake_waitactive() wake_up(&vt_activate_queue) - void reset_vc(struct vc_data *vc) { vc->vc_mode = KD_TEXT; @@ -1256,12 +1377,216 @@ void vc_SAK(struct work_struct *work) release_console_sem(); } +#ifdef CONFIG_COMPAT + +struct compat_consolefontdesc { + unsigned short charcount; /* characters in font (256 or 512) */ + unsigned short charheight; /* scan lines per character (1-32) */ + compat_caddr_t chardata; /* font data in expanded form */ +}; + +static inline int +compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd, + int perm, struct console_font_op *op) +{ + struct compat_consolefontdesc cfdarg; + int i; + + if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc))) + return -EFAULT; + + switch (cmd) { + case PIO_FONTX: + if (!perm) + return -EPERM; + op->op = KD_FONT_OP_SET; + op->flags = KD_FONT_FLAG_OLD; + op->width = 8; + op->height = cfdarg.charheight; + op->charcount = cfdarg.charcount; + op->data = compat_ptr(cfdarg.chardata); + return con_font_op(vc_cons[fg_console].d, op); + case GIO_FONTX: + op->op = KD_FONT_OP_GET; + op->flags = KD_FONT_FLAG_OLD; + op->width = 8; + op->height = cfdarg.charheight; + op->charcount = cfdarg.charcount; + op->data = compat_ptr(cfdarg.chardata); + i = con_font_op(vc_cons[fg_console].d, op); + if (i) + return i; + cfdarg.charheight = op->height; + cfdarg.charcount = op->charcount; + if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc))) + return -EFAULT; + return 0; + } + return -EINVAL; +} + +struct compat_console_font_op { + compat_uint_t op; /* operation code KD_FONT_OP_* */ + compat_uint_t flags; /* KD_FONT_FLAG_* */ + compat_uint_t width, height; /* font size */ + compat_uint_t charcount; + compat_caddr_t data; /* font data with height fixed to 32 */ +}; + +static inline int +compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop, + int perm, struct console_font_op *op, struct vc_data *vc) +{ + int i; + + if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op))) + return -EFAULT; + if (!perm && op->op != KD_FONT_OP_GET) + return -EPERM; + op->data = compat_ptr(((struct compat_console_font_op *)op)->data); + op->flags |= KD_FONT_FLAG_OLD; + i = con_font_op(vc, op); + if (i) + return i; + ((struct compat_console_font_op *)op)->data = (unsigned long)op->data; + if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op))) + return -EFAULT; + return 0; +} + +struct compat_unimapdesc { + unsigned short entry_ct; + compat_caddr_t entries; +}; + +static inline int +compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud, + int perm, struct vc_data *vc) +{ + struct compat_unimapdesc tmp; + struct unipair __user *tmp_entries; + + if (copy_from_user(&tmp, user_ud, sizeof tmp)) + return -EFAULT; + tmp_entries = compat_ptr(tmp.entries); + if (tmp_entries) + if (!access_ok(VERIFY_WRITE, tmp_entries, + tmp.entry_ct*sizeof(struct unipair))) + return -EFAULT; + switch (cmd) { + case PIO_UNIMAP: + if (!perm) + return -EPERM; + return con_set_unimap(vc, tmp.entry_ct, tmp_entries); + case GIO_UNIMAP: + if (!perm && fg_console != vc->vc_num) + return -EPERM; + return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries); + } + return 0; +} + +long vt_compat_ioctl(struct tty_struct *tty, struct file * file, + unsigned int cmd, unsigned long arg) +{ + struct vc_data *vc = tty->driver_data; + struct console_font_op op; /* used in multiple places here */ + struct kbd_struct *kbd; + unsigned int console; + void __user *up = (void __user *)arg; + int perm; + int ret = 0; + + console = vc->vc_num; + + lock_kernel(); + + if (!vc_cons_allocated(console)) { /* impossible? */ + ret = -ENOIOCTLCMD; + goto out; + } + + /* + * To have permissions to do most of the vt ioctls, we either have + * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG. + */ + perm = 0; + if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG)) + perm = 1; + + kbd = kbd_table + console; + switch (cmd) { + /* + * these need special handlers for incompatible data structures + */ + case PIO_FONTX: + case GIO_FONTX: + ret = compat_fontx_ioctl(cmd, up, perm, &op); + break; + + case KDFONTOP: + ret = compat_kdfontop_ioctl(up, perm, &op, vc); + break; + + case PIO_UNIMAP: + case GIO_UNIMAP: + ret = do_unimap_ioctl(cmd, up, perm, vc); + break; + + /* + * all these treat 'arg' as an integer + */ + case KIOCSOUND: + case KDMKTONE: +#ifdef CONFIG_X86 + case KDADDIO: + case KDDELIO: +#endif + case KDSETMODE: + case KDMAPDISP: + case KDUNMAPDISP: + case KDSKBMODE: + case KDSKBMETA: + case KDSKBLED: + case KDSETLED: + case KDSIGACCEPT: + case VT_ACTIVATE: + case VT_WAITACTIVE: + case VT_RELDISP: + case VT_DISALLOCATE: + case VT_RESIZE: + case VT_RESIZEX: + goto fallback; + + /* + * the rest has a compatible data structure behind arg, + * but we have to convert it to a proper 64 bit pointer. + */ + default: + arg = (unsigned long)compat_ptr(arg); + goto fallback; + } +out: + unlock_kernel(); + return ret; + +fallback: + unlock_kernel(); + return vt_ioctl(tty, file, cmd, arg); +} + + +#endif /* CONFIG_COMPAT */ + + /* - * Performs the back end of a vt switch + * Performs the back end of a vt switch. Called under the console + * semaphore. */ static void complete_change_console(struct vc_data *vc) { unsigned char old_vc_mode; + int old = fg_console; last_console = fg_console; @@ -1325,7 +1650,7 @@ static void complete_change_console(struct vc_data *vc) /* * Wake anyone waiting for their VT to activate */ - vt_wake_waitactive(); + vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num); return; } @@ -1398,3 +1723,58 @@ void change_console(struct vc_data *new_vc) complete_change_console(new_vc); } + +/* Perform a kernel triggered VT switch for suspend/resume */ + +static int disable_vt_switch; + +int vt_move_to_console(unsigned int vt, int alloc) +{ + int prev; + + acquire_console_sem(); + /* Graphics mode - up to X */ + if (disable_vt_switch) { + release_console_sem(); + return 0; + } + prev = fg_console; + + if (alloc && vc_allocate(vt)) { + /* we can't have a free VC for now. Too bad, + * we don't want to mess the screen for now. */ + release_console_sem(); + return -ENOSPC; + } + + if (set_console(vt)) { + /* + * We're unable to switch to the SUSPEND_CONSOLE. + * Let the calling function know so it can decide + * what to do. + */ + release_console_sem(); + return -EIO; + } + release_console_sem(); + if (vt_waitactive(vt + 1)) { + pr_debug("Suspend: Can't switch VCs."); + return -EINTR; + } + return prev; +} + +/* + * Normally during a suspend, we allocate a new console and switch to it. + * When we resume, we switch back to the original console. This switch + * can be slow, so on systems where the framebuffer can handle restoration + * of video registers anyways, there's little point in doing the console + * switch. This function allows you to disable it by passing it '0'. + */ +void pm_set_vt_switch(int do_switch) +{ + acquire_console_sem(); + disable_vt_switch = !do_switch; + release_console_sem(); +} +EXPORT_SYMBOL(pm_set_vt_switch); |