| Message ID | 1383336984-26601-3-git-send-email-dh.herrmann@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi On Fri, Nov 1, 2013 at 9:16 PM, David Herrmann <dh.herrmann@gmail.com> wrote: > As we painfully noticed during the 3.12 merge-window our > EVIOCGABS/EVIOCSABS API is limited to ABS_MAX<=0x3f. We tried several > hacks to work around it but if we ever decide to increase ABS_MAX, the > EVIOCSABS ioctl ABI might overflow into the next byte causing horrible > misinterpretations in the kernel that we cannot catch. > > Therefore, we decided to go with ABS_MAX2/CNT2 and introduce two new > ioctls to get/set abs-params. They no longer encode the ABS code in the > ioctl number and thus allow up to 4 billion ABS codes. > > The new API also allows to query multiple ABS values with one call. To > allow EVIOCSABS2(code = 0, cnt = ABS_CNT2) we need to silently ignore > writes to ABS_MT_SLOT. Other than that, semantics are the same as for the > legacy API. I'm currently having a hard time making this properly work with backwards-compatibility in mind. It can get really hairy to properly detect whether a kernel supports ABS2 or not (during runtime). Any objections to increasing the EVDEV version field? User-space could then easily know whether EVIOCGABS2 is supported. Just as a note: the libevdev test-suite runs just fine with this patch, so at least it shouldn't break backwards-compat this time. Anyway, I would feel a lot better if we can let this stay in linux-next for one cycle. Thanks David > Signed-off-by: David Herrmann <dh.herrmann@gmail.com> > --- > drivers/hid/hid-debug.c | 2 +- > drivers/hid/hid-input.c | 2 +- > drivers/input/evdev.c | 88 +++++++++++++++++++++++++++++++- > drivers/input/input.c | 14 ++--- > drivers/input/keyboard/goldfish_events.c | 6 +-- > drivers/input/keyboard/hil_kbd.c | 2 +- > drivers/input/misc/uinput.c | 6 +-- > include/linux/hid.h | 2 +- > include/linux/input.h | 6 +-- > include/uapi/linux/input.h | 37 +++++++++++++- > include/uapi/linux/uinput.h | 2 +- > 11 files changed, 144 insertions(+), 23 deletions(-) > > diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c > index 8453214..d32fa30 100644 > --- a/drivers/hid/hid-debug.c > +++ b/drivers/hid/hid-debug.c > @@ -862,7 +862,7 @@ static const char *relatives[REL_MAX + 1] = { > [REL_WHEEL] = "Wheel", [REL_MISC] = "Misc", > }; > > -static const char *absolutes[ABS_CNT] = { > +static const char *absolutes[ABS_CNT2] = { > [ABS_X] = "X", [ABS_Y] = "Y", > [ABS_Z] = "Z", [ABS_RX] = "Rx", > [ABS_RY] = "Ry", [ABS_RZ] = "Rz", > diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c > index d97f232..a02721c 100644 > --- a/drivers/hid/hid-input.c > +++ b/drivers/hid/hid-input.c > @@ -1300,7 +1300,7 @@ static bool hidinput_has_been_populated(struct hid_input *hidinput) > for (i = 0; i < BITS_TO_LONGS(REL_CNT); i++) > r |= hidinput->input->relbit[i]; > > - for (i = 0; i < BITS_TO_LONGS(ABS_CNT); i++) > + for (i = 0; i < BITS_TO_LONGS(ABS_CNT2); i++) > r |= hidinput->input->absbit[i]; > > for (i = 0; i < BITS_TO_LONGS(MSC_CNT); i++) > diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c > index b6ded17..ffe65fd 100644 > --- a/drivers/input/evdev.c > +++ b/drivers/input/evdev.c > @@ -635,7 +635,7 @@ static int handle_eviocgbit(struct input_dev *dev, > case 0: bits = dev->evbit; len = EV_MAX; break; > case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; > case EV_REL: bits = dev->relbit; len = REL_MAX; break; > - case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; > + case EV_ABS: bits = dev->absbit; len = ABS_MAX2; break; > case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; > case EV_LED: bits = dev->ledbit; len = LED_MAX; break; > case EV_SND: bits = dev->sndbit; len = SND_MAX; break; > @@ -663,6 +663,86 @@ static int handle_eviocgbit(struct input_dev *dev, > } > #undef OLD_KEY_MAX > > +static int evdev_handle_get_abs2(struct input_dev *dev, void __user *p) > +{ > + u32 code, cnt, i; > + struct input_absinfo2 __user *pinfo = p; > + struct input_absinfo abs; > + > + if (!dev->absinfo) > + return -EINVAL; > + > + if (copy_from_user(&code, &pinfo->code, sizeof(code))) > + return -EFAULT; > + if (copy_from_user(&cnt, &pinfo->cnt, sizeof(cnt))) > + return -EFAULT; > + > + if (!cnt || code > ABS_MAX2 || cnt > ABS_CNT2) > + return -EINVAL; > + if (code + cnt > ABS_MAX2) > + return -EINVAL; > + > + for (i = 0; i < cnt; ++i) { > + /* > + * Take event lock to ensure that we are not > + * copying data while EVIOCSABS2 changes it. > + * Might be inconsistent, otherwise. > + */ > + spin_lock_irq(&dev->event_lock); > + abs = dev->absinfo[code + i]; > + spin_unlock_irq(&dev->event_lock); > + > + if (copy_to_user(&pinfo->info[i], &abs, sizeof(abs))) > + return -EFAULT; > + } > + > + return 0; > +} > + > +static int evdev_handle_set_abs2(struct input_dev *dev, void __user *p) > +{ > + struct input_absinfo2 __user *pinfo = p; > + struct input_absinfo *abs; > + u32 code, cnt, i; > + size_t size; > + > + if (!dev->absinfo) > + return -EINVAL; > + > + if (copy_from_user(&code, &pinfo->code, sizeof(code))) > + return -EFAULT; > + if (copy_from_user(&cnt, &pinfo->cnt, sizeof(cnt))) > + return -EFAULT; > + > + if (!cnt || code > ABS_MAX2 || cnt > ABS_CNT2) > + return -EINVAL; > + if (code + cnt > ABS_MAX2) > + return -EINVAL; > + > + size = cnt * sizeof(*abs); > + abs = memdup_user(&pinfo->info[0], size); > + if (IS_ERR(abs)) > + return PTR_ERR(abs); > + > + /* > + * Take event lock to ensure that we are not > + * changing device parameters in the middle > + * of event. > + */ > + spin_lock_irq(&dev->event_lock); > + for (i = 0; i < cnt; ++i) { > + /* silently drop ABS_MT_SLOT */ > + if (code + i == ABS_MT_SLOT) > + continue; > + > + dev->absinfo[code + i] = abs[i]; > + } > + spin_unlock_irq(&dev->event_lock); > + > + kfree(abs); > + return 0; > +} > + > static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p) > { > struct input_keymap_entry ke = { > @@ -890,6 +970,12 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd, > client->clkid = i; > return 0; > > + case EVIOCGABS2: > + return evdev_handle_get_abs2(dev, p); > + > + case EVIOCSABS2: > + return evdev_handle_set_abs2(dev, p); > + > case EVIOCGKEYCODE: > return evdev_handle_get_keycode(dev, p); > > diff --git a/drivers/input/input.c b/drivers/input/input.c > index c044699..bc88f17 100644 > --- a/drivers/input/input.c > +++ b/drivers/input/input.c > @@ -305,7 +305,7 @@ static int input_get_disposition(struct input_dev *dev, > break; > > case EV_ABS: > - if (is_event_supported(code, dev->absbit, ABS_MAX)) > + if (is_event_supported(code, dev->absbit, ABS_MAX2)) > disposition = input_handle_abs_event(dev, code, &value); > > break; > @@ -474,7 +474,7 @@ EXPORT_SYMBOL(input_inject_event); > void input_alloc_absinfo(struct input_dev *dev) > { > if (!dev->absinfo) > - dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo), > + dev->absinfo = kcalloc(ABS_CNT2, sizeof(struct input_absinfo), > GFP_KERNEL); > > WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__); > @@ -954,7 +954,7 @@ static const struct input_device_id *input_match_device(struct input_handler *ha > if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX)) > continue; > > - if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX)) > + if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX2)) > continue; > > if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX)) > @@ -1147,7 +1147,7 @@ static int input_devices_seq_show(struct seq_file *seq, void *v) > if (test_bit(EV_REL, dev->evbit)) > input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX); > if (test_bit(EV_ABS, dev->evbit)) > - input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX); > + input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX2); > if (test_bit(EV_MSC, dev->evbit)) > input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX); > if (test_bit(EV_LED, dev->evbit)) > @@ -1333,7 +1333,7 @@ static int input_print_modalias(char *buf, int size, struct input_dev *id, > len += input_print_modalias_bits(buf + len, size - len, > 'r', id->relbit, 0, REL_MAX); > len += input_print_modalias_bits(buf + len, size - len, > - 'a', id->absbit, 0, ABS_MAX); > + 'a', id->absbit, 0, ABS_MAX2); > len += input_print_modalias_bits(buf + len, size - len, > 'm', id->mscbit, 0, MSC_MAX); > len += input_print_modalias_bits(buf + len, size - len, > @@ -1592,7 +1592,7 @@ static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env) > if (test_bit(EV_REL, dev->evbit)) > INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX); > if (test_bit(EV_ABS, dev->evbit)) > - INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX); > + INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX2); > if (test_bit(EV_MSC, dev->evbit)) > INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX); > if (test_bit(EV_LED, dev->evbit)) > @@ -1924,7 +1924,7 @@ static unsigned int input_estimate_events_per_packet(struct input_dev *dev) > > events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */ > > - for (i = 0; i < ABS_CNT; i++) { > + for (i = 0; i < ABS_CNT2; i++) { > if (test_bit(i, dev->absbit)) { > if (input_is_mt_axis(i)) > events += mt_slots; > diff --git a/drivers/input/keyboard/goldfish_events.c b/drivers/input/keyboard/goldfish_events.c > index 9f60a2e..9999cea 100644 > --- a/drivers/input/keyboard/goldfish_events.c > +++ b/drivers/input/keyboard/goldfish_events.c > @@ -90,8 +90,8 @@ static void events_import_abs_params(struct event_dev *edev) > __raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE); > > count = __raw_readl(addr + REG_LEN) / sizeof(val); > - if (count > ABS_MAX) > - count = ABS_MAX; > + if (count > ABS_MAX2) > + count = ABS_MAX2; > > for (i = 0; i < count; i++) { > if (!test_bit(i, input_dev->absbit)) > @@ -158,7 +158,7 @@ static int events_probe(struct platform_device *pdev) > events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX); > events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX); > events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX); > - events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX); > + events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX2); > events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX); > events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX); > events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX); > diff --git a/drivers/input/keyboard/hil_kbd.c b/drivers/input/keyboard/hil_kbd.c > index 589e3c2..4e4e010 100644 > --- a/drivers/input/keyboard/hil_kbd.c > +++ b/drivers/input/keyboard/hil_kbd.c > @@ -387,7 +387,7 @@ static void hil_dev_pointer_setup(struct hil_dev *ptr) > 0, HIL_IDD_AXIS_MAX(idd, i - 3), 0, 0); > > #ifdef TABLET_AUTOADJUST > - for (i = 0; i < ABS_MAX; i++) { > + for (i = 0; i < ABS_MAX2; i++) { > int diff = input_abs_get_max(input_dev, ABS_X + i) / 10; > input_abs_set_min(input_dev, ABS_X + i, > input_abs_get_min(input_dev, ABS_X + i) + diff); > diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c > index 3cd84d2..2f7355e 100644 > --- a/drivers/input/misc/uinput.c > +++ b/drivers/input/misc/uinput.c > @@ -311,7 +311,7 @@ static int uinput_validate_absbits(struct input_dev *dev) > unsigned int cnt; > int retval = 0; > > - for (cnt = 0; cnt < ABS_CNT; cnt++) { > + for (cnt = 0; cnt < ABS_CNT2; cnt++) { > int min, max; > if (!test_bit(cnt, dev->absbit)) > continue; > @@ -474,7 +474,7 @@ static int uinput_setup_device2(struct uinput_device *udev, > return -EINVAL; > > /* rough check to avoid huge kernel space allocations */ > - max = ABS_CNT * sizeof(*user_dev2->abs) + sizeof(*user_dev2); > + max = ABS_CNT2 * sizeof(*user_dev2->abs) + sizeof(*user_dev2); > if (count > max) > return -EINVAL; > > @@ -770,7 +770,7 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, > break; > > case UI_SET_ABSBIT: > - retval = uinput_set_bit(arg, absbit, ABS_MAX); > + retval = uinput_set_bit(arg, absbit, ABS_MAX2); > break; > > case UI_SET_MSCBIT: > diff --git a/include/linux/hid.h b/include/linux/hid.h > index 31b9d29..c21d8bb 100644 > --- a/include/linux/hid.h > +++ b/include/linux/hid.h > @@ -828,7 +828,7 @@ static inline void hid_map_usage(struct hid_input *hidinput, > switch (type) { > case EV_ABS: > *bit = input->absbit; > - *max = ABS_MAX; > + *max = ABS_MAX2; > break; > case EV_REL: > *bit = input->relbit; > diff --git a/include/linux/input.h b/include/linux/input.h > index 82ce323..c6add6f 100644 > --- a/include/linux/input.h > +++ b/include/linux/input.h > @@ -129,7 +129,7 @@ struct input_dev { > unsigned long evbit[BITS_TO_LONGS(EV_CNT)]; > unsigned long keybit[BITS_TO_LONGS(KEY_CNT)]; > unsigned long relbit[BITS_TO_LONGS(REL_CNT)]; > - unsigned long absbit[BITS_TO_LONGS(ABS_CNT)]; > + unsigned long absbit[BITS_TO_LONGS(ABS_CNT2)]; > unsigned long mscbit[BITS_TO_LONGS(MSC_CNT)]; > unsigned long ledbit[BITS_TO_LONGS(LED_CNT)]; > unsigned long sndbit[BITS_TO_LONGS(SND_CNT)]; > @@ -210,8 +210,8 @@ struct input_dev { > #error "REL_MAX and INPUT_DEVICE_ID_REL_MAX do not match" > #endif > > -#if ABS_MAX != INPUT_DEVICE_ID_ABS_MAX > -#error "ABS_MAX and INPUT_DEVICE_ID_ABS_MAX do not match" > +#if ABS_MAX2 != INPUT_DEVICE_ID_ABS_MAX > +#error "ABS_MAX2 and INPUT_DEVICE_ID_ABS_MAX do not match" > #endif > > #if MSC_MAX != INPUT_DEVICE_ID_MSC_MAX > diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h > index a372627..9e525f9 100644 > --- a/include/uapi/linux/input.h > +++ b/include/uapi/linux/input.h > @@ -74,6 +74,27 @@ struct input_absinfo { > }; > > /** > + * struct input_absinfo2 - used by EVIOC[G/S]ABS2 ioctls > + * @code: First ABS code to query > + * @cnt: Number of ABS codes to query starting at @code > + * @info: #@cnt absinfo structures to get/set abs parameters for all codes > + * > + * This structure is used by the new EVIOC[G/S]ABS2 ioctls which > + * do the same as the old EVIOC[G/S]ABS ioctls but avoid encoding > + * the ABS code in the ioctl number. This allows a much wider > + * range of ABS codes. Furthermore, it allows to query multiple codes with a > + * single call. > + * > + * Note that this silently drops any requests to set ABS_MT_SLOT. Hence, it is > + * allowed to call this with code=0 cnt=ABS_CNT2. > + */ > +struct input_absinfo2 { > + __u32 code; > + __u32 cnt; > + struct input_absinfo info[1]; > +}; > + > +/** > * struct input_keymap_entry - used by EVIOCGKEYCODE/EVIOCSKEYCODE ioctls > * @scancode: scancode represented in machine-endian form. > * @len: length of the scancode that resides in @scancode buffer. > @@ -153,6 +174,8 @@ struct input_keymap_entry { > > #define EVIOCGRAB _IOW('E', 0x90, int) /* Grab/Release device */ > #define EVIOCREVOKE _IOW('E', 0x91, int) /* Revoke device access */ > +#define EVIOCGABS2 _IOR('E', 0x92, struct input_absinfo2) /* get abs value/limits */ > +#define EVIOCSABS2 _IOW('E', 0x93, struct input_absinfo2) /* set abs value/limits */ > > #define EVIOCSCLOCKID _IOW('E', 0xa0, int) /* Set clockid to be used for timestamps */ > > @@ -832,11 +855,23 @@ struct input_keymap_entry { > #define ABS_MT_TOOL_X 0x3c /* Center X tool position */ > #define ABS_MT_TOOL_Y 0x3d /* Center Y tool position */ > > - > +/* > + * ABS_MAX/CNT is limited to a maximum of 0x3f due to the design of EVIOCGABS > + * and EVIOCSABS ioctls. Other kernel APIs like uinput also hardcoded it. Do > + * not modify this value and instead use the extended ABS_MAX2/CNT2 API. > + */ > #define ABS_MAX 0x3f > #define ABS_CNT (ABS_MAX+1) > > /* > + * Due to API restrictions the legacy evdev API only supports ABS values up to > + * ABS_MAX/CNT. Use the extended *ABS2 ioctls to operate on any ABS values in > + * between ABS_MAX and ABS_MAX2. > + */ > +#define ABS_MAX2 0x3f > +#define ABS_CNT2 (ABS_MAX2+1) > + > +/* > * Switch events > */ > > diff --git a/include/uapi/linux/uinput.h b/include/uapi/linux/uinput.h > index c2e8710..27ee521 100644 > --- a/include/uapi/linux/uinput.h > +++ b/include/uapi/linux/uinput.h > @@ -140,7 +140,7 @@ struct uinput_user_dev2 { > char name[UINPUT_MAX_NAME_SIZE]; > struct input_id id; > __u32 ff_effects_max; > - struct input_absinfo abs[ABS_CNT]; > + struct input_absinfo abs[ABS_CNT2]; > }; > > #endif /* _UAPI__UINPUT_H_ */ > -- > 1.8.4.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c index 8453214..d32fa30 100644 --- a/drivers/hid/hid-debug.c +++ b/drivers/hid/hid-debug.c @@ -862,7 +862,7 @@ static const char *relatives[REL_MAX + 1] = { [REL_WHEEL] = "Wheel", [REL_MISC] = "Misc", }; -static const char *absolutes[ABS_CNT] = { +static const char *absolutes[ABS_CNT2] = { [ABS_X] = "X", [ABS_Y] = "Y", [ABS_Z] = "Z", [ABS_RX] = "Rx", [ABS_RY] = "Ry", [ABS_RZ] = "Rz", diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index d97f232..a02721c 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -1300,7 +1300,7 @@ static bool hidinput_has_been_populated(struct hid_input *hidinput) for (i = 0; i < BITS_TO_LONGS(REL_CNT); i++) r |= hidinput->input->relbit[i]; - for (i = 0; i < BITS_TO_LONGS(ABS_CNT); i++) + for (i = 0; i < BITS_TO_LONGS(ABS_CNT2); i++) r |= hidinput->input->absbit[i]; for (i = 0; i < BITS_TO_LONGS(MSC_CNT); i++) diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index b6ded17..ffe65fd 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -635,7 +635,7 @@ static int handle_eviocgbit(struct input_dev *dev, case 0: bits = dev->evbit; len = EV_MAX; break; case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; case EV_REL: bits = dev->relbit; len = REL_MAX; break; - case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; + case EV_ABS: bits = dev->absbit; len = ABS_MAX2; break; case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; case EV_LED: bits = dev->ledbit; len = LED_MAX; break; case EV_SND: bits = dev->sndbit; len = SND_MAX; break; @@ -663,6 +663,86 @@ static int handle_eviocgbit(struct input_dev *dev, } #undef OLD_KEY_MAX +static int evdev_handle_get_abs2(struct input_dev *dev, void __user *p) +{ + u32 code, cnt, i; + struct input_absinfo2 __user *pinfo = p; + struct input_absinfo abs; + + if (!dev->absinfo) + return -EINVAL; + + if (copy_from_user(&code, &pinfo->code, sizeof(code))) + return -EFAULT; + if (copy_from_user(&cnt, &pinfo->cnt, sizeof(cnt))) + return -EFAULT; + + if (!cnt || code > ABS_MAX2 || cnt > ABS_CNT2) + return -EINVAL; + if (code + cnt > ABS_MAX2) + return -EINVAL; + + for (i = 0; i < cnt; ++i) { + /* + * Take event lock to ensure that we are not + * copying data while EVIOCSABS2 changes it. + * Might be inconsistent, otherwise. + */ + spin_lock_irq(&dev->event_lock); + abs = dev->absinfo[code + i]; + spin_unlock_irq(&dev->event_lock); + + if (copy_to_user(&pinfo->info[i], &abs, sizeof(abs))) + return -EFAULT; + } + + return 0; +} + +static int evdev_handle_set_abs2(struct input_dev *dev, void __user *p) +{ + struct input_absinfo2 __user *pinfo = p; + struct input_absinfo *abs; + u32 code, cnt, i; + size_t size; + + if (!dev->absinfo) + return -EINVAL; + + if (copy_from_user(&code, &pinfo->code, sizeof(code))) + return -EFAULT; + if (copy_from_user(&cnt, &pinfo->cnt, sizeof(cnt))) + return -EFAULT; + + if (!cnt || code > ABS_MAX2 || cnt > ABS_CNT2) + return -EINVAL; + if (code + cnt > ABS_MAX2) + return -EINVAL; + + size = cnt * sizeof(*abs); + abs = memdup_user(&pinfo->info[0], size); + if (IS_ERR(abs)) + return PTR_ERR(abs); + + /* + * Take event lock to ensure that we are not + * changing device parameters in the middle + * of event. + */ + spin_lock_irq(&dev->event_lock); + for (i = 0; i < cnt; ++i) { + /* silently drop ABS_MT_SLOT */ + if (code + i == ABS_MT_SLOT) + continue; + + dev->absinfo[code + i] = abs[i]; + } + spin_unlock_irq(&dev->event_lock); + + kfree(abs); + return 0; +} + static int evdev_handle_get_keycode(struct input_dev *dev, void __user *p) { struct input_keymap_entry ke = { @@ -890,6 +970,12 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd, client->clkid = i; return 0; + case EVIOCGABS2: + return evdev_handle_get_abs2(dev, p); + + case EVIOCSABS2: + return evdev_handle_set_abs2(dev, p); + case EVIOCGKEYCODE: return evdev_handle_get_keycode(dev, p); diff --git a/drivers/input/input.c b/drivers/input/input.c index c044699..bc88f17 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -305,7 +305,7 @@ static int input_get_disposition(struct input_dev *dev, break; case EV_ABS: - if (is_event_supported(code, dev->absbit, ABS_MAX)) + if (is_event_supported(code, dev->absbit, ABS_MAX2)) disposition = input_handle_abs_event(dev, code, &value); break; @@ -474,7 +474,7 @@ EXPORT_SYMBOL(input_inject_event); void input_alloc_absinfo(struct input_dev *dev) { if (!dev->absinfo) - dev->absinfo = kcalloc(ABS_CNT, sizeof(struct input_absinfo), + dev->absinfo = kcalloc(ABS_CNT2, sizeof(struct input_absinfo), GFP_KERNEL); WARN(!dev->absinfo, "%s(): kcalloc() failed?\n", __func__); @@ -954,7 +954,7 @@ static const struct input_device_id *input_match_device(struct input_handler *ha if (!bitmap_subset(id->relbit, dev->relbit, REL_MAX)) continue; - if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX)) + if (!bitmap_subset(id->absbit, dev->absbit, ABS_MAX2)) continue; if (!bitmap_subset(id->mscbit, dev->mscbit, MSC_MAX)) @@ -1147,7 +1147,7 @@ static int input_devices_seq_show(struct seq_file *seq, void *v) if (test_bit(EV_REL, dev->evbit)) input_seq_print_bitmap(seq, "REL", dev->relbit, REL_MAX); if (test_bit(EV_ABS, dev->evbit)) - input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX); + input_seq_print_bitmap(seq, "ABS", dev->absbit, ABS_MAX2); if (test_bit(EV_MSC, dev->evbit)) input_seq_print_bitmap(seq, "MSC", dev->mscbit, MSC_MAX); if (test_bit(EV_LED, dev->evbit)) @@ -1333,7 +1333,7 @@ static int input_print_modalias(char *buf, int size, struct input_dev *id, len += input_print_modalias_bits(buf + len, size - len, 'r', id->relbit, 0, REL_MAX); len += input_print_modalias_bits(buf + len, size - len, - 'a', id->absbit, 0, ABS_MAX); + 'a', id->absbit, 0, ABS_MAX2); len += input_print_modalias_bits(buf + len, size - len, 'm', id->mscbit, 0, MSC_MAX); len += input_print_modalias_bits(buf + len, size - len, @@ -1592,7 +1592,7 @@ static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env) if (test_bit(EV_REL, dev->evbit)) INPUT_ADD_HOTPLUG_BM_VAR("REL=", dev->relbit, REL_MAX); if (test_bit(EV_ABS, dev->evbit)) - INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX); + INPUT_ADD_HOTPLUG_BM_VAR("ABS=", dev->absbit, ABS_MAX2); if (test_bit(EV_MSC, dev->evbit)) INPUT_ADD_HOTPLUG_BM_VAR("MSC=", dev->mscbit, MSC_MAX); if (test_bit(EV_LED, dev->evbit)) @@ -1924,7 +1924,7 @@ static unsigned int input_estimate_events_per_packet(struct input_dev *dev) events = mt_slots + 1; /* count SYN_MT_REPORT and SYN_REPORT */ - for (i = 0; i < ABS_CNT; i++) { + for (i = 0; i < ABS_CNT2; i++) { if (test_bit(i, dev->absbit)) { if (input_is_mt_axis(i)) events += mt_slots; diff --git a/drivers/input/keyboard/goldfish_events.c b/drivers/input/keyboard/goldfish_events.c index 9f60a2e..9999cea 100644 --- a/drivers/input/keyboard/goldfish_events.c +++ b/drivers/input/keyboard/goldfish_events.c @@ -90,8 +90,8 @@ static void events_import_abs_params(struct event_dev *edev) __raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE); count = __raw_readl(addr + REG_LEN) / sizeof(val); - if (count > ABS_MAX) - count = ABS_MAX; + if (count > ABS_MAX2) + count = ABS_MAX2; for (i = 0; i < count; i++) { if (!test_bit(i, input_dev->absbit)) @@ -158,7 +158,7 @@ static int events_probe(struct platform_device *pdev) events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX); events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX); events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX); - events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX); + events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX2); events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX); events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX); events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX); diff --git a/drivers/input/keyboard/hil_kbd.c b/drivers/input/keyboard/hil_kbd.c index 589e3c2..4e4e010 100644 --- a/drivers/input/keyboard/hil_kbd.c +++ b/drivers/input/keyboard/hil_kbd.c @@ -387,7 +387,7 @@ static void hil_dev_pointer_setup(struct hil_dev *ptr) 0, HIL_IDD_AXIS_MAX(idd, i - 3), 0, 0); #ifdef TABLET_AUTOADJUST - for (i = 0; i < ABS_MAX; i++) { + for (i = 0; i < ABS_MAX2; i++) { int diff = input_abs_get_max(input_dev, ABS_X + i) / 10; input_abs_set_min(input_dev, ABS_X + i, input_abs_get_min(input_dev, ABS_X + i) + diff); diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c index 3cd84d2..2f7355e 100644 --- a/drivers/input/misc/uinput.c +++ b/drivers/input/misc/uinput.c @@ -311,7 +311,7 @@ static int uinput_validate_absbits(struct input_dev *dev) unsigned int cnt; int retval = 0; - for (cnt = 0; cnt < ABS_CNT; cnt++) { + for (cnt = 0; cnt < ABS_CNT2; cnt++) { int min, max; if (!test_bit(cnt, dev->absbit)) continue; @@ -474,7 +474,7 @@ static int uinput_setup_device2(struct uinput_device *udev, return -EINVAL; /* rough check to avoid huge kernel space allocations */ - max = ABS_CNT * sizeof(*user_dev2->abs) + sizeof(*user_dev2); + max = ABS_CNT2 * sizeof(*user_dev2->abs) + sizeof(*user_dev2); if (count > max) return -EINVAL; @@ -770,7 +770,7 @@ static long uinput_ioctl_handler(struct file *file, unsigned int cmd, break; case UI_SET_ABSBIT: - retval = uinput_set_bit(arg, absbit, ABS_MAX); + retval = uinput_set_bit(arg, absbit, ABS_MAX2); break; case UI_SET_MSCBIT: diff --git a/include/linux/hid.h b/include/linux/hid.h index 31b9d29..c21d8bb 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -828,7 +828,7 @@ static inline void hid_map_usage(struct hid_input *hidinput, switch (type) { case EV_ABS: *bit = input->absbit; - *max = ABS_MAX; + *max = ABS_MAX2; break; case EV_REL: *bit = input->relbit; diff --git a/include/linux/input.h b/include/linux/input.h index 82ce323..c6add6f 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -129,7 +129,7 @@ struct input_dev { unsigned long evbit[BITS_TO_LONGS(EV_CNT)]; unsigned long keybit[BITS_TO_LONGS(KEY_CNT)]; unsigned long relbit[BITS_TO_LONGS(REL_CNT)]; - unsigned long absbit[BITS_TO_LONGS(ABS_CNT)]; + unsigned long absbit[BITS_TO_LONGS(ABS_CNT2)]; unsigned long mscbit[BITS_TO_LONGS(MSC_CNT)]; unsigned long ledbit[BITS_TO_LONGS(LED_CNT)]; unsigned long sndbit[BITS_TO_LONGS(SND_CNT)]; @@ -210,8 +210,8 @@ struct input_dev { #error "REL_MAX and INPUT_DEVICE_ID_REL_MAX do not match" #endif -#if ABS_MAX != INPUT_DEVICE_ID_ABS_MAX -#error "ABS_MAX and INPUT_DEVICE_ID_ABS_MAX do not match" +#if ABS_MAX2 != INPUT_DEVICE_ID_ABS_MAX +#error "ABS_MAX2 and INPUT_DEVICE_ID_ABS_MAX do not match" #endif #if MSC_MAX != INPUT_DEVICE_ID_MSC_MAX diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h index a372627..9e525f9 100644 --- a/include/uapi/linux/input.h +++ b/include/uapi/linux/input.h @@ -74,6 +74,27 @@ struct input_absinfo { }; /** + * struct input_absinfo2 - used by EVIOC[G/S]ABS2 ioctls + * @code: First ABS code to query + * @cnt: Number of ABS codes to query starting at @code + * @info: #@cnt absinfo structures to get/set abs parameters for all codes + * + * This structure is used by the new EVIOC[G/S]ABS2 ioctls which + * do the same as the old EVIOC[G/S]ABS ioctls but avoid encoding + * the ABS code in the ioctl number. This allows a much wider + * range of ABS codes. Furthermore, it allows to query multiple codes with a + * single call. + * + * Note that this silently drops any requests to set ABS_MT_SLOT. Hence, it is + * allowed to call this with code=0 cnt=ABS_CNT2. + */ +struct input_absinfo2 { + __u32 code; + __u32 cnt; + struct input_absinfo info[1]; +}; + +/** * struct input_keymap_entry - used by EVIOCGKEYCODE/EVIOCSKEYCODE ioctls * @scancode: scancode represented in machine-endian form. * @len: length of the scancode that resides in @scancode buffer. @@ -153,6 +174,8 @@ struct input_keymap_entry { #define EVIOCGRAB _IOW('E', 0x90, int) /* Grab/Release device */ #define EVIOCREVOKE _IOW('E', 0x91, int) /* Revoke device access */ +#define EVIOCGABS2 _IOR('E', 0x92, struct input_absinfo2) /* get abs value/limits */ +#define EVIOCSABS2 _IOW('E', 0x93, struct input_absinfo2) /* set abs value/limits */ #define EVIOCSCLOCKID _IOW('E', 0xa0, int) /* Set clockid to be used for timestamps */ @@ -832,11 +855,23 @@ struct input_keymap_entry { #define ABS_MT_TOOL_X 0x3c /* Center X tool position */ #define ABS_MT_TOOL_Y 0x3d /* Center Y tool position */ - +/* + * ABS_MAX/CNT is limited to a maximum of 0x3f due to the design of EVIOCGABS + * and EVIOCSABS ioctls. Other kernel APIs like uinput also hardcoded it. Do + * not modify this value and instead use the extended ABS_MAX2/CNT2 API. + */ #define ABS_MAX 0x3f #define ABS_CNT (ABS_MAX+1) /* + * Due to API restrictions the legacy evdev API only supports ABS values up to + * ABS_MAX/CNT. Use the extended *ABS2 ioctls to operate on any ABS values in + * between ABS_MAX and ABS_MAX2. + */ +#define ABS_MAX2 0x3f +#define ABS_CNT2 (ABS_MAX2+1) + +/* * Switch events */ diff --git a/include/uapi/linux/uinput.h b/include/uapi/linux/uinput.h index c2e8710..27ee521 100644 --- a/include/uapi/linux/uinput.h +++ b/include/uapi/linux/uinput.h @@ -140,7 +140,7 @@ struct uinput_user_dev2 { char name[UINPUT_MAX_NAME_SIZE]; struct input_id id; __u32 ff_effects_max; - struct input_absinfo abs[ABS_CNT]; + struct input_absinfo abs[ABS_CNT2]; }; #endif /* _UAPI__UINPUT_H_ */
As we painfully noticed during the 3.12 merge-window our EVIOCGABS/EVIOCSABS API is limited to ABS_MAX<=0x3f. We tried several hacks to work around it but if we ever decide to increase ABS_MAX, the EVIOCSABS ioctl ABI might overflow into the next byte causing horrible misinterpretations in the kernel that we cannot catch. Therefore, we decided to go with ABS_MAX2/CNT2 and introduce two new ioctls to get/set abs-params. They no longer encode the ABS code in the ioctl number and thus allow up to 4 billion ABS codes. The new API also allows to query multiple ABS values with one call. To allow EVIOCSABS2(code = 0, cnt = ABS_CNT2) we need to silently ignore writes to ABS_MT_SLOT. Other than that, semantics are the same as for the legacy API. Signed-off-by: David Herrmann <dh.herrmann@gmail.com> --- drivers/hid/hid-debug.c | 2 +- drivers/hid/hid-input.c | 2 +- drivers/input/evdev.c | 88 +++++++++++++++++++++++++++++++- drivers/input/input.c | 14 ++--- drivers/input/keyboard/goldfish_events.c | 6 +-- drivers/input/keyboard/hil_kbd.c | 2 +- drivers/input/misc/uinput.c | 6 +-- include/linux/hid.h | 2 +- include/linux/input.h | 6 +-- include/uapi/linux/input.h | 37 +++++++++++++- include/uapi/linux/uinput.h | 2 +- 11 files changed, 144 insertions(+), 23 deletions(-)