diff options
Diffstat (limited to 'drivers/tty/vt')
-rw-r--r-- | drivers/tty/vt/selection.c | 199 | ||||
-rw-r--r-- | drivers/tty/vt/vt.c | 152 | ||||
-rw-r--r-- | drivers/tty/vt/vt_ioctl.c | 75 |
3 files changed, 224 insertions, 202 deletions
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index d7d2e4b844bc..d54a549c5892 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -35,18 +35,18 @@ /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */ #define isspace(c) ((c) == ' ') -extern void poke_blanked_console(void); - /* FIXME: all this needs locking */ -/* Variables for selection control. */ -/* Use a dynamic buffer, instead of static (Dec 1994) */ -struct vc_data *sel_cons; /* must not be deallocated */ -static int use_unicode; -static volatile int sel_start = -1; /* cleared by clear_selection */ -static int sel_end; -static int sel_buffer_lth; -static char *sel_buffer; -static DEFINE_MUTEX(sel_lock); +static struct vc_selection { + struct mutex lock; + struct vc_data *cons; /* must not be deallocated */ + char *buffer; + unsigned int buf_len; + volatile int start; /* cleared by clear_selection */ + int end; +} vc_sel = { + .lock = __MUTEX_INITIALIZER(vc_sel.lock), + .start = -1, +}; /* clear_selection, highlight and highlight_pointer can be called from interrupt (via scrollback/front) */ @@ -54,22 +54,21 @@ static DEFINE_MUTEX(sel_lock); /* set reverse video on characters s-e of console with selection. */ static inline void highlight(const int s, const int e) { - invert_screen(sel_cons, s, e-s+2, 1); + invert_screen(vc_sel.cons, s, e-s+2, 1); } /* use complementary color to show the pointer */ static inline void highlight_pointer(const int where) { - complement_pos(sel_cons, where); + complement_pos(vc_sel.cons, where); } static u32 -sel_pos(int n) +sel_pos(int n, bool unicode) { - if (use_unicode) - return screen_glyph_unicode(sel_cons, n / 2); - return inverse_translate(sel_cons, screen_glyph(sel_cons, n), - 0); + if (unicode) + return screen_glyph_unicode(vc_sel.cons, n / 2); + return inverse_translate(vc_sel.cons, screen_glyph(vc_sel.cons, n), 0); } /** @@ -81,13 +80,18 @@ sel_pos(int n) void clear_selection(void) { highlight_pointer(-1); /* hide the pointer */ - if (sel_start != -1) { - highlight(sel_start, sel_end); - sel_start = -1; + if (vc_sel.start != -1) { + highlight(vc_sel.start, vc_sel.end); + vc_sel.start = -1; } } EXPORT_SYMBOL_GPL(clear_selection); +bool vc_is_sel(struct vc_data *vc) +{ + return vc == vc_sel.cons; +} + /* * User settable table: what characters are to be considered alphabetic? * 128 bits. Locked by the console lock. @@ -186,9 +190,10 @@ static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct * struct vc_data *vc = vc_cons[fg_console].d; int new_sel_start, new_sel_end, spc; char *bp, *obp; - int i, ps, pe, multiplier; + int i, ps, pe; u32 c; - int mode, ret = 0; + int ret = 0; + bool unicode; poke_blanked_console(); @@ -211,57 +216,51 @@ static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct * return 0; } - if (ps > pe) /* make sel_start <= sel_end */ + if (ps > pe) /* make vc_sel.start <= vc_sel.end */ swap(ps, pe); - if (sel_cons != vc_cons[fg_console].d) { + if (vc_sel.cons != vc_cons[fg_console].d) { clear_selection(); - sel_cons = vc_cons[fg_console].d; + vc_sel.cons = vc_cons[fg_console].d; } - mode = vt_do_kdgkbmode(fg_console); - if (mode == K_UNICODE) - use_unicode = 1; - else - use_unicode = 0; - - switch (v->sel_mode) - { - case TIOCL_SELCHAR: /* character-by-character selection */ + unicode = vt_do_kdgkbmode(fg_console) == K_UNICODE; + + switch (v->sel_mode) { + case TIOCL_SELCHAR: /* character-by-character selection */ + new_sel_start = ps; + new_sel_end = pe; + break; + case TIOCL_SELWORD: /* word-by-word selection */ + spc = isspace(sel_pos(ps, unicode)); + for (new_sel_start = ps; ; ps -= 2) { + if ((spc && !isspace(sel_pos(ps, unicode))) || + (!spc && !inword(sel_pos(ps, unicode)))) + break; new_sel_start = ps; + if (!(ps % vc->vc_size_row)) + break; + } + + spc = isspace(sel_pos(pe, unicode)); + for (new_sel_end = pe; ; pe += 2) { + if ((spc && !isspace(sel_pos(pe, unicode))) || + (!spc && !inword(sel_pos(pe, unicode)))) + break; new_sel_end = pe; - break; - case TIOCL_SELWORD: /* word-by-word selection */ - spc = isspace(sel_pos(ps)); - for (new_sel_start = ps; ; ps -= 2) - { - if ((spc && !isspace(sel_pos(ps))) || - (!spc && !inword(sel_pos(ps)))) - break; - new_sel_start = ps; - if (!(ps % vc->vc_size_row)) - break; - } - spc = isspace(sel_pos(pe)); - for (new_sel_end = pe; ; pe += 2) - { - if ((spc && !isspace(sel_pos(pe))) || - (!spc && !inword(sel_pos(pe)))) - break; - new_sel_end = pe; - if (!((pe + 2) % vc->vc_size_row)) - break; - } - break; - case TIOCL_SELLINE: /* line-by-line selection */ - new_sel_start = ps - ps % vc->vc_size_row; - new_sel_end = pe + vc->vc_size_row - - pe % vc->vc_size_row - 2; - break; - case TIOCL_SELPOINTER: - highlight_pointer(pe); - return 0; - default: - return -EINVAL; + if (!((pe + 2) % vc->vc_size_row)) + break; + } + break; + case TIOCL_SELLINE: /* line-by-line selection */ + new_sel_start = rounddown(ps, vc->vc_size_row); + new_sel_end = rounddown(pe, vc->vc_size_row) + + vc->vc_size_row - 2; + break; + case TIOCL_SELPOINTER: + highlight_pointer(pe); + return 0; + default: + return -EINVAL; } /* remove the pointer */ @@ -270,56 +269,56 @@ static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct * /* select to end of line if on trailing space */ if (new_sel_end > new_sel_start && !atedge(new_sel_end, vc->vc_size_row) && - isspace(sel_pos(new_sel_end))) { + isspace(sel_pos(new_sel_end, unicode))) { for (pe = new_sel_end + 2; ; pe += 2) - if (!isspace(sel_pos(pe)) || + if (!isspace(sel_pos(pe, unicode)) || atedge(pe, vc->vc_size_row)) break; - if (isspace(sel_pos(pe))) + if (isspace(sel_pos(pe, unicode))) new_sel_end = pe; } - if (sel_start == -1) /* no current selection */ + if (vc_sel.start == -1) /* no current selection */ highlight(new_sel_start, new_sel_end); - else if (new_sel_start == sel_start) + else if (new_sel_start == vc_sel.start) { - if (new_sel_end == sel_end) /* no action required */ + if (new_sel_end == vc_sel.end) /* no action required */ return 0; - else if (new_sel_end > sel_end) /* extend to right */ - highlight(sel_end + 2, new_sel_end); + else if (new_sel_end > vc_sel.end) /* extend to right */ + highlight(vc_sel.end + 2, new_sel_end); else /* contract from right */ - highlight(new_sel_end + 2, sel_end); + highlight(new_sel_end + 2, vc_sel.end); } - else if (new_sel_end == sel_end) + else if (new_sel_end == vc_sel.end) { - if (new_sel_start < sel_start) /* extend to left */ - highlight(new_sel_start, sel_start - 2); + if (new_sel_start < vc_sel.start) /* extend to left */ + highlight(new_sel_start, vc_sel.start - 2); else /* contract from left */ - highlight(sel_start, new_sel_start - 2); + highlight(vc_sel.start, new_sel_start - 2); } else /* some other case; start selection from scratch */ { clear_selection(); highlight(new_sel_start, new_sel_end); } - sel_start = new_sel_start; - sel_end = new_sel_end; + vc_sel.start = new_sel_start; + vc_sel.end = new_sel_end; /* Allocate a new buffer before freeing the old one ... */ - multiplier = use_unicode ? 4 : 1; /* chars can take up to 4 bytes */ - bp = kmalloc_array((sel_end - sel_start) / 2 + 1, multiplier, + /* chars can take up to 4 bytes with unicode */ + bp = kmalloc_array((vc_sel.end - vc_sel.start) / 2 + 1, unicode ? 4 : 1, GFP_KERNEL); if (!bp) { printk(KERN_WARNING "selection: kmalloc() failed\n"); clear_selection(); return -ENOMEM; } - kfree(sel_buffer); - sel_buffer = bp; + kfree(vc_sel.buffer); + vc_sel.buffer = bp; obp = bp; - for (i = sel_start; i <= sel_end; i += 2) { - c = sel_pos(i); - if (use_unicode) + for (i = vc_sel.start; i <= vc_sel.end; i += 2) { + c = sel_pos(i, unicode); + if (unicode) bp += store_utf8(c, bp); else *bp++ = c; @@ -335,7 +334,7 @@ static int __set_selection_kernel(struct tiocl_selection *v, struct tty_struct * obp = bp; } } - sel_buffer_lth = bp - sel_buffer; + vc_sel.buf_len = bp - vc_sel.buffer; return ret; } @@ -344,11 +343,11 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty) { int ret; - mutex_lock(&sel_lock); + mutex_lock(&vc_sel.lock); console_lock(); ret = __set_selection_kernel(v, tty); console_unlock(); - mutex_unlock(&sel_lock); + mutex_unlock(&vc_sel.lock); return ret; } @@ -380,26 +379,26 @@ int paste_selection(struct tty_struct *tty) tty_buffer_lock_exclusive(&vc->port); add_wait_queue(&vc->paste_wait, &wait); - mutex_lock(&sel_lock); - while (sel_buffer && sel_buffer_lth > pasted) { + mutex_lock(&vc_sel.lock); + while (vc_sel.buffer && vc_sel.buf_len > pasted) { set_current_state(TASK_INTERRUPTIBLE); if (signal_pending(current)) { ret = -EINTR; break; } if (tty_throttled(tty)) { - mutex_unlock(&sel_lock); + mutex_unlock(&vc_sel.lock); schedule(); - mutex_lock(&sel_lock); + mutex_lock(&vc_sel.lock); continue; } __set_current_state(TASK_RUNNING); - count = sel_buffer_lth - pasted; - count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL, + count = vc_sel.buf_len - pasted; + count = tty_ldisc_receive_buf(ld, vc_sel.buffer + pasted, NULL, count); pasted += count; } - mutex_unlock(&sel_lock); + mutex_unlock(&vc_sel.lock); remove_wait_queue(&vc->paste_wait, &wait); __set_current_state(TASK_RUNNING); diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 15d27698054a..309a39197be0 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -890,8 +890,9 @@ static void hide_softcursor(struct vc_data *vc) static void hide_cursor(struct vc_data *vc) { - if (vc == sel_cons) + if (vc_is_sel(vc)) clear_selection(); + vc->vc_sw->con_cursor(vc, CM_ERASE); hide_softcursor(vc); } @@ -901,7 +902,7 @@ static void set_cursor(struct vc_data *vc) if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS) return; if (vc->vc_deccm) { - if (vc == sel_cons) + if (vc_is_sel(vc)) clear_selection(); add_softcursor(vc); if ((vc->vc_cursor_type & 0x0f) != 1) @@ -1074,6 +1075,17 @@ static void visual_deinit(struct vc_data *vc) module_put(vc->vc_sw->owner); } +static void vc_port_destruct(struct tty_port *port) +{ + struct vc_data *vc = container_of(port, struct vc_data, port); + + kfree(vc); +} + +static const struct tty_port_operations vc_port_ops = { + .destruct = vc_port_destruct, +}; + int vc_allocate(unsigned int currcons) /* return 0 on success */ { struct vt_notifier_param param; @@ -1099,6 +1111,7 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */ vc_cons[currcons].d = vc; tty_port_init(&vc->port); + vc->port.ops = &vc_port_ops; INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK); visual_init(vc, currcons, 1); @@ -1207,7 +1220,7 @@ static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc, } } - if (vc == sel_cons) + if (vc_is_sel(vc)) clear_selection(); old_rows = vc->vc_rows; @@ -1901,67 +1914,65 @@ static void set_mode(struct vc_data *vc, int on_off) /* console_lock is held */ static void setterm_command(struct vc_data *vc) { - switch(vc->vc_par[0]) { - case 1: /* set color for underline mode */ - if (vc->vc_can_do_color && - vc->vc_par[1] < 16) { - vc->vc_ulcolor = color_table[vc->vc_par[1]]; - if (vc->vc_underline) - update_attr(vc); - } - break; - case 2: /* set color for half intensity mode */ - if (vc->vc_can_do_color && - vc->vc_par[1] < 16) { - vc->vc_halfcolor = color_table[vc->vc_par[1]]; - if (vc->vc_intensity == 0) - update_attr(vc); - } - break; - case 8: /* store colors as defaults */ - vc->vc_def_color = vc->vc_attr; - if (vc->vc_hi_font_mask == 0x100) - vc->vc_def_color >>= 1; - default_attr(vc); - update_attr(vc); - break; - case 9: /* set blanking interval */ - blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60; - poke_blanked_console(); - break; - case 10: /* set bell frequency in Hz */ - if (vc->vc_npar >= 1) - vc->vc_bell_pitch = vc->vc_par[1]; - else - vc->vc_bell_pitch = DEFAULT_BELL_PITCH; - break; - case 11: /* set bell duration in msec */ - if (vc->vc_npar >= 1) - vc->vc_bell_duration = (vc->vc_par[1] < 2000) ? - msecs_to_jiffies(vc->vc_par[1]) : 0; - else - vc->vc_bell_duration = DEFAULT_BELL_DURATION; - break; - case 12: /* bring specified console to the front */ - if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1)) - set_console(vc->vc_par[1] - 1); - break; - case 13: /* unblank the screen */ - poke_blanked_console(); - break; - case 14: /* set vesa powerdown interval */ - vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ; - break; - case 15: /* activate the previous console */ - set_console(last_console); - break; - case 16: /* set cursor blink duration in msec */ - if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 && - vc->vc_par[1] <= USHRT_MAX) - vc->vc_cur_blink_ms = vc->vc_par[1]; - else - vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; - break; + switch (vc->vc_par[0]) { + case 1: /* set color for underline mode */ + if (vc->vc_can_do_color && vc->vc_par[1] < 16) { + vc->vc_ulcolor = color_table[vc->vc_par[1]]; + if (vc->vc_underline) + update_attr(vc); + } + break; + case 2: /* set color for half intensity mode */ + if (vc->vc_can_do_color && vc->vc_par[1] < 16) { + vc->vc_halfcolor = color_table[vc->vc_par[1]]; + if (vc->vc_intensity == 0) + update_attr(vc); + } + break; + case 8: /* store colors as defaults */ + vc->vc_def_color = vc->vc_attr; + if (vc->vc_hi_font_mask == 0x100) + vc->vc_def_color >>= 1; + default_attr(vc); + update_attr(vc); + break; + case 9: /* set blanking interval */ + blankinterval = min(vc->vc_par[1], 60U) * 60; + poke_blanked_console(); + break; + case 10: /* set bell frequency in Hz */ + if (vc->vc_npar >= 1) + vc->vc_bell_pitch = vc->vc_par[1]; + else + vc->vc_bell_pitch = DEFAULT_BELL_PITCH; + break; + case 11: /* set bell duration in msec */ + if (vc->vc_npar >= 1) + vc->vc_bell_duration = (vc->vc_par[1] < 2000) ? + msecs_to_jiffies(vc->vc_par[1]) : 0; + else + vc->vc_bell_duration = DEFAULT_BELL_DURATION; + break; + case 12: /* bring specified console to the front */ + if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1)) + set_console(vc->vc_par[1] - 1); + break; + case 13: /* unblank the screen */ + poke_blanked_console(); + break; + case 14: /* set vesa powerdown interval */ + vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ; + break; + case 15: /* activate the previous console */ + set_console(last_console); + break; + case 16: /* set cursor blink duration in msec */ + if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 && + vc->vc_par[1] <= USHRT_MAX) + vc->vc_cur_blink_ms = vc->vc_par[1]; + else + vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; + break; } } @@ -2576,8 +2587,6 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co if (in_interrupt()) return count; - might_sleep(); - console_lock(); vc = tty->driver_data; if (vc == NULL) { @@ -3253,6 +3262,7 @@ static int con_install(struct tty_driver *driver, struct tty_struct *tty) tty->driver_data = vc; vc->port.tty = tty; + tty_port_get(&vc->port); if (!tty->winsize.ws_row && !tty->winsize.ws_col) { tty->winsize.ws_row = vc_cons[currcons].d->vc_rows; @@ -3288,6 +3298,13 @@ static void con_shutdown(struct tty_struct *tty) console_unlock(); } +static void con_cleanup(struct tty_struct *tty) +{ + struct vc_data *vc = tty->driver_data; + + tty_port_put(&vc->port); +} + static int default_color = 7; /* white */ static int default_italic_color = 2; // green (ASCII) static int default_underline_color = 3; // cyan (ASCII) @@ -3413,7 +3430,8 @@ static const struct tty_operations con_ops = { .throttle = con_throttle, .unthrottle = con_unthrottle, .resize = vt_resize, - .shutdown = con_shutdown + .shutdown = con_shutdown, + .cleanup = con_cleanup, }; static struct cdev vc0_cdev; diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c index ee6c91ef1f6c..daf61c28ba76 100644 --- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -39,11 +39,32 @@ #include <linux/kbd_diacr.h> #include <linux/selection.h> -char vt_dont_switch; -extern struct tty_driver *console_driver; +bool vt_dont_switch; -#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count) -#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons) +static inline bool vt_in_use(unsigned int i) +{ + const struct vc_data *vc = vc_cons[i].d; + + /* + * console_lock must be held to prevent the vc from being deallocated + * while we're checking whether it's in-use. + */ + WARN_CONSOLE_UNLOCKED(); + + return vc && kref_read(&vc->port.kref) > 1; +} + +static inline bool vt_busy(int i) +{ + if (vt_in_use(i)) + return true; + if (i == fg_console) + return true; + if (vc_is_sel(vc_cons[i].d)) + return true; + + return false; +} /* * Console (vt and kd) routines, as defined by USL SVR4 manual, and by @@ -289,16 +310,14 @@ static int vt_disallocate(unsigned int vc_num) int ret = 0; console_lock(); - if (VT_BUSY(vc_num)) + if (vt_busy(vc_num)) ret = -EBUSY; else if (vc_num) vc = vc_deallocate(vc_num); console_unlock(); - if (vc && vc_num >= MIN_NR_CONSOLES) { - tty_port_destroy(&vc->port); - kfree(vc); - } + if (vc && vc_num >= MIN_NR_CONSOLES) + tty_port_put(&vc->port); return ret; } @@ -311,17 +330,15 @@ static void vt_disallocate_all(void) console_lock(); for (i = 1; i < MAX_NR_CONSOLES; i++) - if (!VT_BUSY(i)) + if (!vt_busy(i)) vc[i] = vc_deallocate(i); else vc[i] = NULL; console_unlock(); for (i = 1; i < MAX_NR_CONSOLES; i++) { - if (vc[i] && i >= MIN_NR_CONSOLES) { - tty_port_destroy(&vc[i]->port); - kfree(vc[i]); - } + if (vc[i] && i >= MIN_NR_CONSOLES) + tty_port_put(&vc[i]->port); } } @@ -335,22 +352,13 @@ int vt_ioctl(struct tty_struct *tty, { struct vc_data *vc = tty->driver_data; struct console_font_op op; /* used in multiple places here */ - unsigned int console; + unsigned int console = vc->vc_num; unsigned char ucval; unsigned int uival; void __user *up = (void __user *)arg; int i, perm; int ret = 0; - console = vc->vc_num; - - - 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. @@ -641,15 +649,16 @@ int vt_ioctl(struct tty_struct *tty, struct vt_stat __user *vtstat = up; unsigned short state, mask; - /* Review: FIXME: Console lock ? */ if (put_user(fg_console + 1, &vtstat->v_active)) ret = -EFAULT; else { state = 1; /* /dev/tty0 is always open */ + console_lock(); /* required by vt_in_use() */ for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask; ++i, mask <<= 1) - if (VT_IS_IN_USE(i)) + if (vt_in_use(i)) state |= mask; + console_unlock(); ret = put_user(state, &vtstat->v_state); } break; @@ -659,10 +668,11 @@ int vt_ioctl(struct tty_struct *tty, * Returns the first available (non-opened) console. */ case VT_OPENQRY: - /* FIXME: locking ? - but then this is a stupid API */ + console_lock(); /* required by vt_in_use() */ for (i = 0; i < MAX_NR_CONSOLES; ++i) - if (! VT_IS_IN_USE(i)) + if (!vt_in_use(i)) break; + console_unlock(); uival = i < MAX_NR_CONSOLES ? (i+1) : -1; goto setint; @@ -1011,12 +1021,12 @@ int vt_ioctl(struct tty_struct *tty, case VT_LOCKSWITCH: if (!capable(CAP_SYS_TTY_CONFIG)) return -EPERM; - vt_dont_switch = 1; + vt_dont_switch = true; break; case VT_UNLOCKSWITCH: if (!capable(CAP_SYS_TTY_CONFIG)) return -EPERM; - vt_dont_switch = 0; + vt_dont_switch = false; break; case VT_GETHIFONTMASK: ret = put_user(vc->vc_hi_font_mask, @@ -1180,14 +1190,9 @@ long vt_compat_ioctl(struct tty_struct *tty, { struct vc_data *vc = tty->driver_data; struct console_font_op op; /* used in multiple places here */ - unsigned int console = vc->vc_num; void __user *up = compat_ptr(arg); int perm; - - if (!vc_cons_allocated(console)) /* impossible? */ - return -ENOIOCTLCMD; - /* * 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. |