Merge tag 'staging-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging / IIO driver updates from Greg KH:
 "Here is the big staging and iio driver update for 5.2-rc1.

  Lots of tiny fixes all over the staging and IIO driver trees here,
  along with some new IIO drivers.

  The "counter" subsystem was added in here as well, as it is needed by
  the IIO drivers and subsystem.

  Also we ended up deleting two drivers, making this pull request remove
  a few hundred thousand lines of code, always a nice thing to see. Both
  of the drivers removed have been replaced with "real" drivers in their
  various subsystem directories, and they will be coming to you from
  those locations during this merge window.

  There are some core vt/selection changes in here, that was due to some
  cleanups needed for the speakup fixes. Those have all been acked by
  the various subsystem maintainers (i.e. me), so those are ok.

  We also added a few new drivers, for some odd hardware, giving new
  developers plenty to work on with basic coding style cleanups to come
  in the near future.

  Other than that, nothing unusual here.

  All of these have been in linux-next for a while with no reported
  issues, other than an odd gcc warning for one of the new drivers that
  should be fixed up soon"

[ I fixed up the warning myself  - Linus ]

* tag 'staging-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (663 commits)
  staging: kpc2000: kpc_spi: Fix build error for {read,write}q
  Staging: rtl8192e: Remove extra space before break statement
  Staging: rtl8192u: ieee80211: Fix if-else indentation warning
  Staging: rtl8192u: ieee80211: Fix indentation errors by removing extra spaces
  staging: most: cdev: fix chrdev_region leak in mod_exit
  staging: wlan-ng: Fix improper SPDX comment style
  staging: rtl8192u: ieee80211: Resolve ERROR reported by checkpatch
  staging: vc04_services: bcm2835-camera: Compress two lines into one line
  staging: rtl8723bs: core: Use !x in place of NULL comparison.
  staging: rtl8723bs: core: Prefer using the BIT Macro.
  staging: fieldbus: anybus-s: fix wait_for_completion_timeout return handling
  staging: kpc2000: fix up build problems with readq()
  staging: rtlwifi: move remaining phydm .h files
  staging: rtlwifi: strip down phydm .h files
  staging: rtlwifi: delete the staging driver
  staging: fieldbus: anybus-s: rename bus id field to avoid confusion
  staging: fieldbus: anybus-s: keep device bus id in bus endianness
  Staging: sm750fb: Change *array into *const array
  staging: rtl8192u: ieee80211: Fix spelling mistake
  staging: rtl8192u: ieee80211: Replace bit shifting with BIT macro
  ...

1 files changed, 86 insertions, 126 deletions

diff --git a/drivers/staging/speakup/selection.c b/drivers/staging/speakup/selection.c
index 0ed1fefee0e9..a8b4d0c5ab7e 100644
--- a/drivers/staging/speakup/selection.c
+++ b/drivers/staging/speakup/selection.c
@@ -9,178 +9,138 @@
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/atomic.h>
+#include <linux/console.h>
 
 #include "speakup.h"
 
-/* ------ cut and paste ----- */
-/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
-#define ishardspace(c)      ((c) == ' ')
-
 unsigned short spk_xs, spk_ys, spk_xe, spk_ye; /* our region points */
-
-/* Variables for selection control. */
-/* must not be deallocated */
 struct vc_data *spk_sel_cons;
-/* cleared by clear_selection */
-static int sel_start = -1;
-static int sel_end;
-static int sel_buffer_lth;
-static char *sel_buffer;
 
-static unsigned char sel_pos(int n)
-{
-	return inverse_translate(spk_sel_cons,
-		screen_glyph(spk_sel_cons, n), 0);
-}
+struct speakup_selection_work {
+	struct work_struct work;
+	struct tiocl_selection sel;
+	struct tty_struct *tty;
+};
 
 void speakup_clear_selection(void)
 {
-	sel_start = -1;
+	console_lock();
+	clear_selection();
+	console_unlock();
 }
 
-/* does screen address p correspond to character at LH/RH edge of screen? */
-static int atedge(const int p, int size_row)
+static void __speakup_set_selection(struct work_struct *work)
 {
-	return !(p % size_row) || !((p + 2) % size_row);
-}
+	struct speakup_selection_work *ssw =
+		container_of(work, struct speakup_selection_work, work);
 
-/* constrain v such that v <= u */
-static unsigned short limit(const unsigned short v, const unsigned short u)
-{
-	return (v > u) ? u : v;
-}
+	struct tty_struct *tty;
+	struct tiocl_selection sel;
 
-int speakup_set_selection(struct tty_struct *tty)
-{
-	int new_sel_start, new_sel_end;
-	char *bp, *obp;
-	int i, ps, pe;
-	struct vc_data *vc = vc_cons[fg_console].d;
+	sel = ssw->sel;
 
-	spk_xs = limit(spk_xs, vc->vc_cols - 1);
-	spk_ys = limit(spk_ys, vc->vc_rows - 1);
-	spk_xe = limit(spk_xe, vc->vc_cols - 1);
-	spk_ye = limit(spk_ye, vc->vc_rows - 1);
-	ps = spk_ys * vc->vc_size_row + (spk_xs << 1);
-	pe = spk_ye * vc->vc_size_row + (spk_xe << 1);
+	/* this ensures we copy sel before releasing the lock below */
+	rmb();
 
-	if (ps > pe)	/* make sel_start <= sel_end */
-		swap(ps, pe);
+	/* release the lock by setting tty of the struct to NULL */
+	tty = xchg(&ssw->tty, NULL);
 
 	if (spk_sel_cons != vc_cons[fg_console].d) {
-		speakup_clear_selection();
 		spk_sel_cons = vc_cons[fg_console].d;
-		dev_warn(tty->dev,
-			 "Selection: mark console not the same as cut\n");
-		return -EINVAL;
+		pr_warn("Selection: mark console not the same as cut\n");
+		goto unref;
 	}
 
-	new_sel_start = ps;
-	new_sel_end = pe;
-
-	/* select to end of line if on trailing space */
-	if (new_sel_end > new_sel_start &&
-	    !atedge(new_sel_end, vc->vc_size_row) &&
-	    ishardspace(sel_pos(new_sel_end))) {
-		for (pe = new_sel_end + 2; ; pe += 2)
-			if (!ishardspace(sel_pos(pe)) ||
-			    atedge(pe, vc->vc_size_row))
-				break;
-		if (ishardspace(sel_pos(pe)))
-			new_sel_end = pe;
-	}
-	if ((new_sel_start == sel_start) && (new_sel_end == sel_end))
-		return 0; /* no action required */
-
-	sel_start = new_sel_start;
-	sel_end = new_sel_end;
-	/* Allocate a new buffer before freeing the old one ... */
-	bp = kmalloc((sel_end - sel_start) / 2 + 1, GFP_ATOMIC);
-	if (!bp) {
-		speakup_clear_selection();
-		return -ENOMEM;
-	}
-	kfree(sel_buffer);
-	sel_buffer = bp;
-
-	obp = bp;
-	for (i = sel_start; i <= sel_end; i += 2) {
-		*bp = sel_pos(i);
-		if (!ishardspace(*bp++))
-			obp = bp;
-		if (!((i + 2) % vc->vc_size_row)) {
-			/* strip trailing blanks from line and add newline,
-			 * unless non-space at end of line.
-			 */
-			if (obp != bp) {
-				bp = obp;
-				*bp++ = '\r';
-			}
-			obp = bp;
-		}
+	console_lock();
+	set_selection_kernel(&sel, tty);
+	console_unlock();
+
+unref:
+	tty_kref_put(tty);
+}
+
+static struct speakup_selection_work speakup_sel_work = {
+	.work = __WORK_INITIALIZER(speakup_sel_work.work,
+				   __speakup_set_selection)
+};
+
+int speakup_set_selection(struct tty_struct *tty)
+{
+	/* we get kref here first in order to avoid a subtle race when
+	 * cancelling selection work. getting kref first establishes the
+	 * invariant that if speakup_sel_work.tty is not NULL when
+	 * speakup_cancel_selection() is called, it must be the case that a put
+	 * kref is pending.
+	 */
+	tty_kref_get(tty);
+	if (cmpxchg(&speakup_sel_work.tty, NULL, tty)) {
+		tty_kref_put(tty);
+		return -EBUSY;
 	}
-	sel_buffer_lth = bp - sel_buffer;
+	/* now we have the 'lock' by setting tty member of
+	 * speakup_selection_work. wmb() ensures that writes to
+	 * speakup_sel_work don't happen before cmpxchg() above.
+	 */
+	wmb();
+
+	speakup_sel_work.sel.xs = spk_xs + 1;
+	speakup_sel_work.sel.ys = spk_ys + 1;
+	speakup_sel_work.sel.xe = spk_xe + 1;
+	speakup_sel_work.sel.ye = spk_ye + 1;
+	speakup_sel_work.sel.sel_mode = TIOCL_SELCHAR;
+
+	schedule_work_on(WORK_CPU_UNBOUND, &speakup_sel_work.work);
+
 	return 0;
 }
 
-struct speakup_paste_work {
-	struct work_struct work;
+void speakup_cancel_selection(void)
+{
 	struct tty_struct *tty;
-};
+
+	cancel_work_sync(&speakup_sel_work.work);
+	/* setting to null so that if work fails to run and we cancel it,
+	 * we can run it again without getting EBUSY forever from there on.
+	 * we need to use xchg here to avoid race with speakup_set_selection()
+	 */
+	tty = xchg(&speakup_sel_work.tty, NULL);
+	if (tty)
+		tty_kref_put(tty);
+}
 
 static void __speakup_paste_selection(struct work_struct *work)
 {
-	struct speakup_paste_work *spw =
-		container_of(work, struct speakup_paste_work, work);
-	struct tty_struct *tty = xchg(&spw->tty, NULL);
-	struct vc_data *vc = (struct vc_data *)tty->driver_data;
-	int pasted = 0, count;
-	struct tty_ldisc *ld;
-	DECLARE_WAITQUEUE(wait, current);
-
-	ld = tty_ldisc_ref(tty);
-	if (!ld)
-		goto tty_unref;
-	tty_buffer_lock_exclusive(&vc->port);
-
-	add_wait_queue(&vc->paste_wait, &wait);
-	while (sel_buffer && sel_buffer_lth > pasted) {
-		set_current_state(TASK_INTERRUPTIBLE);
-		if (tty_throttled(tty)) {
-			schedule();
-			continue;
-		}
-		count = sel_buffer_lth - pasted;
-		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
-					      count);
-		pasted += count;
-	}
-	remove_wait_queue(&vc->paste_wait, &wait);
-	__set_current_state(TASK_RUNNING);
+	struct speakup_selection_work *ssw =
+		container_of(work, struct speakup_selection_work, work);
+	struct tty_struct *tty = xchg(&ssw->tty, NULL);
 
-	tty_buffer_unlock_exclusive(&vc->port);
-	tty_ldisc_deref(ld);
-tty_unref:
+	paste_selection(tty);
 	tty_kref_put(tty);
 }
 
-static struct speakup_paste_work speakup_paste_work = {
+static struct speakup_selection_work speakup_paste_work = {
 	.work = __WORK_INITIALIZER(speakup_paste_work.work,
 				   __speakup_paste_selection)
 };
 
 int speakup_paste_selection(struct tty_struct *tty)
 {
-	if (cmpxchg(&speakup_paste_work.tty, NULL, tty))
+	tty_kref_get(tty);
+	if (cmpxchg(&speakup_paste_work.tty, NULL, tty)) {
+		tty_kref_put(tty);
 		return -EBUSY;
+	}
 
-	tty_kref_get(tty);
 	schedule_work_on(WORK_CPU_UNBOUND, &speakup_paste_work.work);
 	return 0;
 }
 
 void speakup_cancel_paste(void)
 {
+	struct tty_struct *tty;
+
 	cancel_work_sync(&speakup_paste_work.work);
-	tty_kref_put(speakup_paste_work.tty);
+	tty = xchg(&speakup_paste_work.tty, NULL);
+	if (tty)
+		tty_kref_put(tty);
 }