sched_ext: Maintain an online cid mask in the scheduler arenagrafted

Schedulers on the default cid mapping treat [0, nr_online_cids) as the
online set and restart on hotplug. Schedulers that install their own mapping
with scx_bpf_cid_override() have no way to learn which cids are online: the
count no longer identifies members and the CPU-form cpumask is unusable from
cid programs. This is an obvious hole in the cid API.

Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's
arena, allocated alongside the per-CPU scratch masks and populated after the
cid mapping is finalized and before ops.init(), for child schedulers too.
The pointer stays valid through ops.exit() with no reference to take. It is
the arena offset as a void pointer, the same form struct_ops arena arguments
arrive in. The verifier types the void return as a scalar for the program's
arena cast.

The mask follows the SCX hotplug notifications: seeded from cpu_active_mask
and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask
only inside a hotplug transition. Updates walk the scheduler list under the
lock that also serializes unlinking. Reads are live, not atomic snapshots.
Root initialization excludes hotplug.

v2: Reworded the getter kerneldoc (Andrea Righi).

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>

6 files changed, 277 insertions, 0 deletions

diff --git a/include/dt-bindings/input/atmel-maxtouch.h b/include/dt-bindings/input/atmel-maxtouch.h
new file mode 100644
index 000000000..7345ab322
--- /dev/null
+++ b/include/dt-bindings/input/atmel-maxtouch.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _DT_BINDINGS_ATMEL_MAXTOUCH_H
+#define _DT_BINDINGS_ATMEL_MAXTOUCH_H
+
+#define ATMEL_MXT_WAKEUP_NONE		0
+#define ATMEL_MXT_WAKEUP_I2C_SCL	1
+#define ATMEL_MXT_WAKEUP_GPIO		2
+
+#endif /* _DT_BINDINGS_ATMEL_MAXTOUCH_H */
diff --git a/include/dt-bindings/input/cros-ec-keyboard.h b/include/dt-bindings/input/cros-ec-keyboard.h
new file mode 100644
index 000000000..afc12f6aa
--- /dev/null
+++ b/include/dt-bindings/input/cros-ec-keyboard.h
@@ -0,0 +1,207 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides the constants of the standard Chrome OS key matrix
+ * for cros-ec keyboard-controller bindings.
+ *
+ * Copyright (c) 2021 Google, Inc
+ */
+
+#ifndef _CROS_EC_KEYBOARD_H
+#define _CROS_EC_KEYBOARD_H
+
+#define CROS_STD_TOP_ROW_KEYMAP	\
+	MATRIX_KEY(0x00, 0x02, KEY_F1)	\
+	MATRIX_KEY(0x03, 0x02, KEY_F2)	\
+	MATRIX_KEY(0x02, 0x02, KEY_F3)	\
+	MATRIX_KEY(0x01, 0x02, KEY_F4)	\
+	MATRIX_KEY(0x03, 0x04, KEY_F5)	\
+	MATRIX_KEY(0x02, 0x04, KEY_F6)	\
+	MATRIX_KEY(0x01, 0x04, KEY_F7)	\
+	MATRIX_KEY(0x02, 0x09, KEY_F8)	\
+	MATRIX_KEY(0x01, 0x09, KEY_F9)	\
+	MATRIX_KEY(0x00, 0x04, KEY_F10)
+
+#define CROS_STD_MAIN_KEYMAP	\
+	MATRIX_KEY(0x00, 0x01, KEY_LEFTMETA)	\
+	MATRIX_KEY(0x00, 0x03, KEY_B)		\
+	MATRIX_KEY(0x00, 0x05, KEY_RO)		\
+	MATRIX_KEY(0x00, 0x06, KEY_N)		\
+	MATRIX_KEY(0x00, 0x08, KEY_EQUAL)	\
+	MATRIX_KEY(0x00, 0x0a, KEY_RIGHTALT)	\
+	MATRIX_KEY(0x01, 0x01, KEY_ESC)		\
+	MATRIX_KEY(0x01, 0x03, KEY_G)		\
+	MATRIX_KEY(0x01, 0x06, KEY_H)		\
+	MATRIX_KEY(0x01, 0x08, KEY_APOSTROPHE)	\
+	MATRIX_KEY(0x01, 0x0b, KEY_BACKSPACE)	\
+	MATRIX_KEY(0x01, 0x0c, KEY_HENKAN)	\
+						\
+	MATRIX_KEY(0x02, 0x00, KEY_LEFTCTRL)	\
+	MATRIX_KEY(0x02, 0x01, KEY_TAB)		\
+	MATRIX_KEY(0x02, 0x03, KEY_T)		\
+	MATRIX_KEY(0x02, 0x05, KEY_RIGHTBRACE)	\
+	MATRIX_KEY(0x02, 0x06, KEY_Y)		\
+	MATRIX_KEY(0x02, 0x07, KEY_102ND)	\
+	MATRIX_KEY(0x02, 0x08, KEY_LEFTBRACE)	\
+	MATRIX_KEY(0x02, 0x0a, KEY_YEN)		\
+						\
+	MATRIX_KEY(0x03, 0x00, KEY_LEFTMETA)	\
+	MATRIX_KEY(0x03, 0x01, KEY_GRAVE)	\
+	MATRIX_KEY(0x03, 0x03, KEY_5)		\
+	MATRIX_KEY(0x03, 0x06, KEY_6)		\
+	MATRIX_KEY(0x03, 0x08, KEY_MINUS)	\
+	MATRIX_KEY(0x03, 0x09, KEY_SLEEP)	\
+	MATRIX_KEY(0x03, 0x0b, KEY_BACKSLASH)	\
+	MATRIX_KEY(0x03, 0x0c, KEY_MUHENKAN)	\
+						\
+	MATRIX_KEY(0x04, 0x00, KEY_RIGHTCTRL)	\
+	MATRIX_KEY(0x04, 0x01, KEY_A)		\
+	MATRIX_KEY(0x04, 0x02, KEY_D)		\
+	MATRIX_KEY(0x04, 0x03, KEY_F)		\
+	MATRIX_KEY(0x04, 0x04, KEY_S)		\
+	MATRIX_KEY(0x04, 0x05, KEY_K)		\
+	MATRIX_KEY(0x04, 0x06, KEY_J)		\
+	MATRIX_KEY(0x04, 0x08, KEY_SEMICOLON)	\
+	MATRIX_KEY(0x04, 0x09, KEY_L)		\
+	MATRIX_KEY(0x04, 0x0a, KEY_BACKSLASH)	\
+	MATRIX_KEY(0x04, 0x0b, KEY_ENTER)	\
+						\
+	MATRIX_KEY(0x05, 0x01, KEY_Z)		\
+	MATRIX_KEY(0x05, 0x02, KEY_C)		\
+	MATRIX_KEY(0x05, 0x03, KEY_V)		\
+	MATRIX_KEY(0x05, 0x04, KEY_X)		\
+	MATRIX_KEY(0x05, 0x05, KEY_COMMA)	\
+	MATRIX_KEY(0x05, 0x06, KEY_M)		\
+	MATRIX_KEY(0x05, 0x07, KEY_LEFTSHIFT)	\
+	MATRIX_KEY(0x05, 0x08, KEY_SLASH)	\
+	MATRIX_KEY(0x05, 0x09, KEY_DOT)		\
+	MATRIX_KEY(0x05, 0x0b, KEY_SPACE)	\
+						\
+	MATRIX_KEY(0x06, 0x01, KEY_1)		\
+	MATRIX_KEY(0x06, 0x02, KEY_3)		\
+	MATRIX_KEY(0x06, 0x03, KEY_4)		\
+	MATRIX_KEY(0x06, 0x04, KEY_2)		\
+	MATRIX_KEY(0x06, 0x05, KEY_8)		\
+	MATRIX_KEY(0x06, 0x06, KEY_7)		\
+	MATRIX_KEY(0x06, 0x08, KEY_0)		\
+	MATRIX_KEY(0x06, 0x09, KEY_9)		\
+	MATRIX_KEY(0x06, 0x0a, KEY_LEFTALT)	\
+	MATRIX_KEY(0x06, 0x0b, KEY_DOWN)	\
+	MATRIX_KEY(0x06, 0x0c, KEY_RIGHT)	\
+						\
+	MATRIX_KEY(0x07, 0x01, KEY_Q)		\
+	MATRIX_KEY(0x07, 0x02, KEY_E)		\
+	MATRIX_KEY(0x07, 0x03, KEY_R)		\
+	MATRIX_KEY(0x07, 0x04, KEY_W)		\
+	MATRIX_KEY(0x07, 0x05, KEY_I)		\
+	MATRIX_KEY(0x07, 0x06, KEY_U)		\
+	MATRIX_KEY(0x07, 0x07, KEY_RIGHTSHIFT)	\
+	MATRIX_KEY(0x07, 0x08, KEY_P)		\
+	MATRIX_KEY(0x07, 0x09, KEY_O)		\
+	MATRIX_KEY(0x07, 0x0b, KEY_UP)		\
+	MATRIX_KEY(0x07, 0x0c, KEY_LEFT)
+
+/* No numpad */
+#define CROS_TOP_ROW_KEYMAP_V30 \
+	MATRIX_KEY(0x00, 0x01, KEY_F11)		/* T11 */	\
+	MATRIX_KEY(0x00, 0x02, KEY_F1)		/* T1 */	\
+	MATRIX_KEY(0x00, 0x04, KEY_F10)		/* T10 */	\
+	MATRIX_KEY(0x00, 0x0b, KEY_F14)		/* T14 */	\
+	MATRIX_KEY(0x00, 0x0c, KEY_F15)		/* T15 */	\
+	MATRIX_KEY(0x01, 0x02, KEY_F4)		/* T4 */	\
+	MATRIX_KEY(0x01, 0x04, KEY_F7)		/* T7 */	\
+	MATRIX_KEY(0x01, 0x05, KEY_F12)		/* T12 */	\
+	MATRIX_KEY(0x01, 0x09, KEY_F9)		/* T9 */	\
+	MATRIX_KEY(0x02, 0x02, KEY_F3)		/* T3 */	\
+	MATRIX_KEY(0x02, 0x04, KEY_F6)		/* T6 */	\
+	MATRIX_KEY(0x02, 0x0b, KEY_F8)		/* T8 */	\
+	MATRIX_KEY(0x03, 0x02, KEY_F2)		/* T2 */	\
+	MATRIX_KEY(0x03, 0x05, KEY_F13)		/* T13 */	\
+	MATRIX_KEY(0x04, 0x04, KEY_F5)		/* T5 */
+
+#define CROS_MAIN_KEYMAP_V30			/* Keycode */	\
+	MATRIX_KEY(0x00, 0x03, KEY_B)		/* 50 */	\
+	MATRIX_KEY(0x00, 0x05, KEY_N)		/* 51 */	\
+	MATRIX_KEY(0x00, 0x06, KEY_RO)		/* 56 (JIS) */	\
+	MATRIX_KEY(0x00, 0x08, KEY_EQUAL)	/* 13 */	\
+	MATRIX_KEY(0x00, 0x09, KEY_HOME)	/* 80 (Numpad) */	\
+	MATRIX_KEY(0x00, 0x0a, KEY_RIGHTALT)	/* 62 */	\
+	MATRIX_KEY(0x00, 0x10, KEY_FN)		/* 127 */	\
+								\
+	MATRIX_KEY(0x01, 0x01, KEY_ESC)		/* 110 */	\
+	MATRIX_KEY(0x01, 0x03, KEY_G)		/* 35 */	\
+	MATRIX_KEY(0x01, 0x06, KEY_H)		/* 36 */	\
+	MATRIX_KEY(0x01, 0x08, KEY_APOSTROPHE)	/* 41 */	\
+	MATRIX_KEY(0x01, 0x0b, KEY_BACKSPACE)	/* 15 */	\
+	MATRIX_KEY(0x01, 0x0c, KEY_HENKAN)	/* 65 (JIS) */	\
+	MATRIX_KEY(0x01, 0x0e, KEY_LEFTCTRL)	/* 58 */	\
+								\
+	MATRIX_KEY(0x02, 0x01, KEY_TAB)		/* 16 */	\
+	MATRIX_KEY(0x02, 0x03, KEY_T)		/* 21 */	\
+	MATRIX_KEY(0x02, 0x05, KEY_RIGHTBRACE)	/* 28 */	\
+	MATRIX_KEY(0x02, 0x06, KEY_Y)		/* 22 */	\
+	MATRIX_KEY(0x02, 0x08, KEY_LEFTBRACE)	/* 27 */	\
+	MATRIX_KEY(0x02, 0x09, KEY_DELETE)	/* 76 (Numpad) */	\
+	MATRIX_KEY(0x02, 0x0c, KEY_PAGEUP)	/* 85 (Numpad) */	\
+	MATRIX_KEY(0x02, 0x011, KEY_YEN)	/* 14 (JIS) */	\
+								\
+	MATRIX_KEY(0x03, 0x00, KEY_LEFTMETA)	/* Launcher */	\
+	MATRIX_KEY(0x03, 0x01, KEY_GRAVE)	/* 1 */	\
+	MATRIX_KEY(0x03, 0x03, KEY_5)		/* 6 */	\
+	MATRIX_KEY(0x03, 0x04, KEY_S)		/* 32 */	\
+	MATRIX_KEY(0x03, 0x06, KEY_MINUS)	/* 12 */	\
+	MATRIX_KEY(0x03, 0x08, KEY_6)		/* 7 */		\
+	MATRIX_KEY(0x03, 0x09, KEY_SLEEP)	/* Lock */	\
+	MATRIX_KEY(0x03, 0x0b, KEY_BACKSLASH)	/* 29 */	\
+	MATRIX_KEY(0x03, 0x0c, KEY_MUHENKAN)	/* 63 (JIS) */	\
+	MATRIX_KEY(0x03, 0x0e, KEY_RIGHTCTRL)	/* 64 */	\
+								\
+	MATRIX_KEY(0x04, 0x01, KEY_A)		/* 31 */	\
+	MATRIX_KEY(0x04, 0x02, KEY_D)		/* 33 */	\
+	MATRIX_KEY(0x04, 0x03, KEY_F)		/* 34 */	\
+	MATRIX_KEY(0x04, 0x05, KEY_K)		/* 38 */	\
+	MATRIX_KEY(0x04, 0x06, KEY_J)		/* 37 */	\
+	MATRIX_KEY(0x04, 0x08, KEY_SEMICOLON)	/* 40 */	\
+	MATRIX_KEY(0x04, 0x09, KEY_L)		/* 39 */	\
+	MATRIX_KEY(0x04, 0x0b, KEY_ENTER)	/* 43 */	\
+	MATRIX_KEY(0x04, 0x0c, KEY_END)		/* 81 (Numpad) */	\
+								\
+	MATRIX_KEY(0x05, 0x01, KEY_1)		/* 2 */	\
+	MATRIX_KEY(0x05, 0x02, KEY_COMMA)	/* 53 */	\
+	MATRIX_KEY(0x05, 0x03, KEY_DOT)		/* 54 */	\
+	MATRIX_KEY(0x05, 0x04, KEY_SLASH)	/* 55 */	\
+	MATRIX_KEY(0x05, 0x05, KEY_C)		/* 48 */	\
+	MATRIX_KEY(0x05, 0x06, KEY_SPACE)	/* 61 */	\
+	MATRIX_KEY(0x05, 0x07, KEY_LEFTSHIFT)	/* 44 */	\
+	MATRIX_KEY(0x05, 0x08, KEY_X)		/* 47 */	\
+	MATRIX_KEY(0x05, 0x09, KEY_V)		/* 49 */	\
+	MATRIX_KEY(0x05, 0x0b, KEY_M)		/* 52 */	\
+	MATRIX_KEY(0x05, 0x0c, KEY_PAGEDOWN)	/* 86 (Numpad) */	\
+								\
+	MATRIX_KEY(0x06, 0x01, KEY_Z)		/* 46 */	\
+	MATRIX_KEY(0x06, 0x02, KEY_3)		/* 4 */		\
+	MATRIX_KEY(0x06, 0x03, KEY_4)		/* 5 */		\
+	MATRIX_KEY(0x06, 0x04, KEY_2)		/* 3 */		\
+	MATRIX_KEY(0x06, 0x05, KEY_8)		/* 9 */		\
+	MATRIX_KEY(0x06, 0x06, KEY_0)		/* 11 */	\
+	MATRIX_KEY(0x06, 0x08, KEY_7)		/* 8 */		\
+	MATRIX_KEY(0x06, 0x09, KEY_9)		/* 10 */	\
+	MATRIX_KEY(0x06, 0x0b, KEY_DOWN)	/* 84 */	\
+	MATRIX_KEY(0x06, 0x0c, KEY_RIGHT)	/* 89 */	\
+	MATRIX_KEY(0x06, 0x0d, KEY_LEFTALT)	/* 60 */	\
+	MATRIX_KEY(0x06, 0x0f, KEY_ASSISTANT)	/* 128 */	\
+	MATRIX_KEY(0x06, 0x11, KEY_BACKSLASH)	/* 42 (JIS, ISO) */	\
+								\
+	MATRIX_KEY(0x07, 0x01, KEY_U)		/* 23 */	\
+	MATRIX_KEY(0x07, 0x02, KEY_I)		/* 24 */	\
+	MATRIX_KEY(0x07, 0x03, KEY_O)		/* 25 */	\
+	MATRIX_KEY(0x07, 0x04, KEY_P)		/* 26 */	\
+	MATRIX_KEY(0x07, 0x05, KEY_Q)		/* 17 */	\
+	MATRIX_KEY(0x07, 0x06, KEY_W)		/* 18 */	\
+	MATRIX_KEY(0x07, 0x07, KEY_RIGHTSHIFT)	/* 57 */	\
+	MATRIX_KEY(0x07, 0x08, KEY_E)		/* 19 */	\
+	MATRIX_KEY(0x07, 0x09, KEY_R)		/* 20 */	\
+	MATRIX_KEY(0x07, 0x0b, KEY_UP)		/* 83 */	\
+	MATRIX_KEY(0x07, 0x0c, KEY_LEFT)	/* 79 */	\
+	MATRIX_KEY(0x07, 0x11, KEY_102ND)	/* 45 (ISO) */
+
+#endif /* _CROS_EC_KEYBOARD_H */
diff --git a/include/dt-bindings/input/gpio-keys.h b/include/dt-bindings/input/gpio-keys.h
new file mode 100644
index 000000000..8962df79e
--- /dev/null
+++ b/include/dt-bindings/input/gpio-keys.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for gpio keys bindings.
+ */
+
+#ifndef _DT_BINDINGS_GPIO_KEYS_H
+#define _DT_BINDINGS_GPIO_KEYS_H
+
+#define EV_ACT_ANY		0x00	/* asserted or deasserted */
+#define EV_ACT_ASSERTED		0x01	/* asserted */
+#define EV_ACT_DEASSERTED	0x02	/* deasserted */
+
+#endif /* _DT_BINDINGS_GPIO_KEYS_H */
diff --git a/include/dt-bindings/input/input.h b/include/dt-bindings/input/input.h
new file mode 100644
index 000000000..bcf0ae100
--- /dev/null
+++ b/include/dt-bindings/input/input.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for most input bindings.
+ *
+ * Most input bindings include key code, matrix key code format.
+ * In most cases, key code and matrix key code format uses
+ * the standard values/macro defined in this header.
+ */
+
+#ifndef _DT_BINDINGS_INPUT_INPUT_H
+#define _DT_BINDINGS_INPUT_INPUT_H
+
+#include "linux-event-codes.h"
+
+#define MATRIX_KEY(row, col, code)	\
+	((((row) & 0xFF) << 24) | (((col) & 0xFF) << 16) | ((code) & 0xFFFF))
+
+#endif /* _DT_BINDINGS_INPUT_INPUT_H */
diff --git a/include/dt-bindings/input/linux-event-codes.h b/include/dt-bindings/input/linux-event-codes.h
new file mode 120000
index 000000000..693bbcd26
--- /dev/null
+++ b/include/dt-bindings/input/linux-event-codes.h
@@ -0,0 +1 @@
+../../uapi/linux/input-event-codes.h
\ No newline at end of file
diff --git a/include/dt-bindings/input/ti-drv260x.h b/include/dt-bindings/input/ti-drv260x.h
new file mode 100644
index 000000000..af71082dd
--- /dev/null
+++ b/include/dt-bindings/input/ti-drv260x.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * DRV260X haptics driver family
+ *
+ * Author: Dan Murphy <dmurphy@ti.com>
+ *
+ * Copyright:   (C) 2014 Texas Instruments, Inc.
+ */
+
+#ifndef _DT_BINDINGS_TI_DRV260X_H
+#define _DT_BINDINGS_TI_DRV260X_H
+
+/* Calibration Types */
+#define DRV260X_LRA_MODE		0x00
+#define DRV260X_LRA_NO_CAL_MODE	0x01
+#define DRV260X_ERM_MODE		0x02
+
+/* Library Selection */
+#define DRV260X_LIB_EMPTY			0x00
+#define DRV260X_ERM_LIB_A			0x01
+#define DRV260X_ERM_LIB_B			0x02
+#define DRV260X_ERM_LIB_C			0x03
+#define DRV260X_ERM_LIB_D			0x04
+#define DRV260X_ERM_LIB_E			0x05
+#define DRV260X_LIB_LRA			0x06
+#define DRV260X_ERM_LIB_F			0x07
+
+#endif