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path: root/drivers/char/vt_ioctl.c
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Diffstat (limited to 'drivers/char/vt_ioctl.c')
-rw-r--r--drivers/char/vt_ioctl.c482
1 files changed, 431 insertions, 51 deletions
diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c
index 95189f288f8c..29c651ab0d78 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);
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