When the extended advertisement feature is enabled, a hardcoded min and
max interval of 0x8000 is used.  This patch fixes this issue by using
the configured min/max value.

This was validated by setting min/max in main.conf and making sure the
right setting is applied:

< HCI Command: LE Set Extended Advertising Parameters (0x08|0x0036) plen
25                                          #93 [hci0] 10.953011
…
Min advertising interval: 181.250 msec (0x0122)
Max advertising interval: 181.250 msec (0x0122)
…
Signed-off-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This calls hci_update_background_scan() when there is any update on the
advertisement monitors. If there is at least one advertisement monitor,
the filtering policy of scan parameters should be 0x00. This also reports
device found mgmt events if there is at least one monitor.

The following cases were tested with btmgmt advmon-* commands.
(1) add a ADV monitor and observe that the passive scanning is
triggered.
(2) remove the last ADV monitor and observe that the passive scanning is
terminated.
(3) with a LE peripheral paired, repeat (1) and observe the passive
scanning continues.
(4) with a LE peripheral paired, repeat (2) and observe the passive
scanning continues.
(5) with a ADV monitor, suspend/resume the host and observe the passive
scanning continues.
Signed-off-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

Replace the wakeable boolean with flags in hci_conn_params and all users
of this boolean. This will be used by the get/set device flags mgmt op.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

Since the classic device list now supports flags, convert the wakeable
list into a flag on the existing device list.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

This patch centralized the initialization of default parameters.  This
is required to allow clients to more easily customize the default
system parameters.
Signed-off-by: Alain Michaud <alainm@chromium.org>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Check current scan state by checking HCI_LE_SCAN flag and send scan
disable command only if scan is already enabled.
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Renamed BT_SUSPEND_COMPLETE to BT_SUSPEND_CONFIGURE_WAKE since it sets
up the event filter and whitelist for wake-up.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Alain Michaud <alainm@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

When a device is suspended, it doesn't need to be as responsive to
connection events. Increase the interval to 640ms (creating a duty cycle
of roughly 1.75%) so that passive scanning uses much less power (vs
previous duty cycle of 18.75%). The new window + interval combination
has been tested to work with HID devices (which are currently the only
devices capable of wake up).
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The types for window and interval should be uint16, not uint8.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch fix the advertising handle is set to 0 regardless of actual
instance value. The affected commands are LE Set Advertising Set Random
Address, LE Set Extended Advertising Data, and LE Set Extended Scan
Response Data commands.
Signed-off-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

When starting active scanning for discovery the whitelist is not needed
to be used. So the filter_policy is 0x00. To make the core more readable
use a variable name instead of just setting 0 as paramter.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

BlueZ cancels adv when starting a scan, but does not cancel a scan when
starting to adv. Neither is required, so this brings both to a
consistent state (of not affecting each other). Some very rare (I've
never seen one) BT 4.0 chips will fail to do both at once. Even this is
ok since the command that will fail will be the second one, and thus the
common sense logic of first-come-first-served is preserved for BLE
requests.
Signed-off-by: Dmitry Grinberg <dmitrygr@google.com>
Signed-off-by: Manish Mandlik <mmandlik@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

To prevent spurious wake ups, we disable any discovery or advertising
when we enter suspend and restore it when we exit suspend. While paused,
we disable any management requests to modify discovery or advertising.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

To handle LE devices, we must first disable passive scanning and
disconnect all connected devices. Once that is complete, we update the
whitelist and re-enable scanning
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

To handle BR/EDR devices, we first disable page scan and disconnect all
connected devices. Once that is complete, we add event filters (for
devices that can wake the system) and re-enable page scan.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Register for PM_SUSPEND_PREPARE and PM_POST_SUSPEND to make sure the
Bluetooth controller is prepared correctly for suspend/resume. Implement
the registration, scheduling and task handling portions only in this
patch.
Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

When the RPA generation fails, indicate the error with a device specifc
error message.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

Instances may have flags set as part of its data in which case the code
should not attempt to add it again otherwise it can cause duplication:

< HCI Command: LE Set Extended Advertising Data (0x08|0x0037) plen 35
        Handle: 0x00
        Operation: Complete extended advertising data (0x03)
        Fragment preference: Minimize fragmentation (0x01)
        Data length: 0x06
        Flags: 0x04
          BR/EDR Not Supported
        Flags: 0x06
          LE General Discoverable Mode
          BR/EDR Not Supported
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

Instance 0 is controlled by stack itself and always set the local name
in the scan response.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

When using LE Set Extended Advertising Enable command the duration
refers to the lifetime of instance not the length which is actually
controlled by the interval_min and interval_max when setting the
parameters.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Changes made to add support for fast advertising interval
as per core 4.1 specification, section 9.3.11.2.

A peripheral device entering any of the following GAP modes and
sending either non-connectable advertising events or scannable
undirected advertising events should use adv_fast_interval2
(100ms - 150ms) for adv_fast_period(30s).

         - Non-Discoverable Mode
         - Non-Connectable Mode
         - Limited Discoverable Mode
         - General Discoverable Mode
Signed-off-by: Spoorthi Ravishankar Koppad <spoorthix.k@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This makes use of controller sets when using Extended Advertising
feature thus offloading the scheduling to the controller.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This commit makes the kernel not send the next queued HCI command until
a command complete arrives for the last HCI command sent to the
controller. This change avoids a problem with some buggy controllers
(seen on two SKUs of QCA9377) that send an extra command complete event
for the previous command after the kernel had already sent a new HCI
command to the controller.

The problem was reproduced when starting an active scanning procedure,
where an extra command complete event arrives for the LE_SET_RANDOM_ADDR
command. When this happends the kernel ends up not processing the
command complete for the following commmand, LE_SET_SCAN_PARAM, and
ultimately behaving as if a passive scanning procedure was being
performed, when in fact controller is performing an active scanning
procedure. This makes it impossible to discover BLE devices as no device
found events are sent to userspace.

This problem is reproducible on 100% of the attempts on the affected
controllers. The extra command complete event can be seen at timestamp
27.420131 on the btmon logs bellow.

Bluetooth monitor ver 5.50
= Note: Linux version 5.0.0+ (x86_64)                                  0.352340
= Note: Bluetooth subsystem version 2.22                               0.352343
= New Index: 80:C5:F2:8F:87:84 (Primary,USB,hci0)               [hci0] 0.352344
= Open Index: 80:C5:F2:8F:87:84                                 [hci0] 0.352345
= Index Info: 80:C5:F2:8F:87:84 (Qualcomm)                      [hci0] 0.352346
@ MGMT Open: bluetoothd (privileged) version 1.14             {0x0001} 0.352347
@ MGMT Open: btmon (privileged) version 1.14                  {0x0002} 0.352366
@ MGMT Open: btmgmt (privileged) version 1.14                {0x0003} 27.302164
@ MGMT Command: Start Discovery (0x0023) plen 1       {0x0003} [hci0] 27.302310
        Address type: 0x06
          LE Public
          LE Random
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6   #1 [hci0] 27.302496
        Address: 15:60:F2:91:B2:24 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4                 #2 [hci0] 27.419117
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7  #3 [hci0] 27.419244
        Type: Active (0x01)
        Interval: 11.250 msec (0x0012)
        Window: 11.250 msec (0x0012)
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #4 [hci0] 27.420131
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2      #5 [hci0] 27.420259
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                 #6 [hci0] 27.420969
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #7 [hci0] 27.421983
      LE Set Scan Enable (0x08|0x000c) ncmd 1
        Status: Success (0x00)
@ MGMT Event: Command Complete (0x0001) plen 4        {0x0003} [hci0] 27.422059
      Start Discovery (0x0023) plen 1
        Status: Success (0x00)
        Address type: 0x06
          LE Public
          LE Random
@ MGMT Event: Discovering (0x0013) plen 2             {0x0003} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0002} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0001} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Trivial fix to clean up an indentation issue
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch adds support for advertising in primary and secondary
channel on different PHYs. User can add the phy preference in
the flag based on which phy type will be added in extended
advertising parameter would be set.

@ MGMT Command: Add Advertising (0x003e) plen 11
        Instance: 1
        Flags: 0x00000200
          Advertise in CODED on Secondary channel
        Duration: 0
        Timeout: 0
        Advertising data length: 0
        Scan response length: 0
< HCI Command: LE Set Extended Advertising Enable (0x08|0x0039) plen 2
        Extended advertising: Disabled (0x00)
        Number of sets: Disable all sets (0x00)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Enable (0x08|0x0039) ncmd 2
        Status: Success (0x00)
< HCI Command: LE Set Extended Advertising Parameters (0x08|0x0036) plen 25
        Handle: 0x00
        Properties: 0x0000
        Min advertising interval: 1280.000 msec (0x0800)
        Max advertising interval: 1280.000 msec (0x0800)
        Channel map: 37, 38, 39 (0x07)
        Own address type: Random (0x01)
        Peer address type: Public (0x00)
        Peer address: 00:00:00:00:00:00 (OUI 00-00-00)
        Filter policy: Allow Scan Request from Any, Allow Connect Request from Any (0x00)
        TX power: 127 dbm (0x7f)
        Primary PHY: LE Coded (0x03)
        Secondary max skip: 0x00
        Secondary PHY: LE Coded (0x03)
        SID: 0x00
        Scan request notifications: Disabled (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This basically sets the random address for the adv instance
Random address can be set only if the instance is created which
is done in Set ext adv param.

Random address and rpa expire timer and flags have been added
to adv instance which will be used when the respective
instance is scheduled.

This introduces a hci_get_random_address() which returns the
own address type and random address (rpa or nrpa) based
on the instance flags and hdev flags. New function is required
since own address type should be known before setting adv params
but address can be set only after setting params.

< HCI Command: LE Set Advertising Set Random Address (0x08|0x0035) plen 7
        Advertising handle: 0x00
        Advertising random address: 3C:8E:56:9B:77:84 (OUI 3C-8E-56)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Advertising Set Random Address (0x08|0x0035) ncmd 1
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

If ext adv is enabled then use ext adv to disable as well.
Also remove the adv set during LE disable.

< HCI Command: LE Set Extended Advertising Enable (0x08|0x0039) plen 2
        Extended advertising: Disabled (0x00)
        Number of sets: Disable all sets (0x00)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Enable (0x08|0x0039) ncmd 2
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch implements Set Ext Adv data and Set Ext Scan rsp data
if controller support extended advertising.

Currently the operation is set as Complete data and fragment
preference is set as no fragment

< HCI Command: LE Set Extended Advertising Data (0x08|0x0037) plen 35
        Handle: 0x00
        Operation: Complete extended advertising data (0x03)
        Fragment preference: Minimize fragmentation (0x01)
        Data length: 0x15
        16-bit Service UUIDs (complete): 2 entries
          Heart Rate (0x180d)
          Battery Service (0x180f)
        Name (complete): Test LE
        Company: Google (224)
          Data: 0102
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Data (0x08|0x0037) ncmd 1
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch basically replaces legacy adv with extended adv
based on the controller support. Currently there is no
design change. ie only one adv set will be enabled at a time.

This also adds tx_power in instance and store whatever returns
from Set_ext_parameter, use the same in adv data as well.
For instance 0 tx_power is stored in hdev only.

< HCI Command: LE Set Extended Advertising Parameters (0x08|0x0036) plen 25
        Handle: 0x00
        Properties: 0x0010
          Use legacy advertising PDUs: ADV_NONCONN_IND
        Min advertising interval: 1280.000 msec (0x0800)
        Max advertising interval: 1280.000 msec (0x0800)
        Channel map: 37, 38, 39 (0x07)
        Own address type: Random (0x01)
        Peer address type: Public (0x00)
        Peer address: 00:00:00:00:00:00 (OUI 00-00-00)
        Filter policy: Allow Scan Request from Any, Allow Connect Request from Any (0x00)
        TX power: 127 dbm (0x7f)
        Primary PHY: LE 1M (0x01)
        Secondary max skip: 0x00
        Secondary PHY: LE 1M (0x01)
        SID: 0x00
        Scan request notifications: Disabled (0x00)
> HCI Event: Command Complete (0x0e) plen 5
      LE Set Extended Advertising Parameters (0x08|0x0036) ncmd 1
        Status: Success (0x00)
        TX power (selected): 7 dbm (0x07)
< HCI Command: LE Set Extended Advertising Enable (0x08|0x0039) plen 6
        Extended advertising: Enabled (0x01)
        Number of sets: 1 (0x01)
        Entry 0
          Handle: 0x00
          Duration: 0 ms (0x00)
          Max ext adv events: 0
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Enable (0x08|0x0039) ncmd 2
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Use the PHYs selected in Set Phy Configuration management command
while scanning.

< HCI Command: LE Set Extended Scan Parameters (0x08|0x0041) plen 13
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
        PHYs: 0x05
        Entry 0: LE 1M
          Type: Active (0x01)
          Interval: 11.250 msec (0x0012)
          Window: 11.250 msec (0x0012)
        Entry 1: LE Coded
          Type: Active (0x01)
          Interval: 11.250 msec (0x0012)
          Window: 11.250 msec (0x0012)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Scan Parameters (0x08|0x0041) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Extended Scan Enable (0x08|0x0042) plen 6
        Extended scan: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
        Duration: 0 msec (0x0000)
        Period: 0.00 sec (0x0000)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Scan Enable (0x08|0x0042) ncmd 2
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This implements Set extended scan param and set extended scan enable
commands and use it for start LE scan based on controller support.

The new features added in these commands are setting of new PHY for
scanning and setting of scan duration. Both features are disabled
for now, meaning only 1M PHY is set and scan duration is set to 0
which means that scanning will be done untill scan disable is called.

< HCI Command: LE Set Extended Scan Parameters (0x08|0x0041) plen 8
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
        PHYs: 0x01
        Entry 0: LE 1M
          Type: Active (0x01)
          Interval: 11.250 msec (0x0012)
          Window: 11.250 msec (0x0012)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Scan Parameters (0x08|0x0041) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Extended Scan Enable (0x08|0x0042) plen 6
        Extended scan: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
        Duration: 0 msec (0x0000)
        Period: 0.00 sec (0x0000)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Scan Enable (0x08|0x0042) ncmd 2
        Status: Success (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Introduce a helper hci_req_start_scan() which starts an LE
scan and call it from passive_Scan() and active_scan().
There is not functionality change in this patch.

This is basically done to enable extended scanning if the
controller supports which will be done in the subsequent
patch
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

I've seen timeout errors from HCI commands where it looks like
schedule_timeout() has returned immediately; additional logging for the
error case gives:

	req_status=1 req_result=0 remaining=10000 jiffies

so the device is still in state HCI_REQ_PEND and the value returned by
schedule_timeout() is the same as the original timeout (HCI_INIT_TIMEOUT
on a system with HZ=1000).

Use wait_event_interruptible_timeout() instead of open-coding similar
behaviour which is subject to the spurious failure described above.
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

This patch fixes incorrect checks for LE states.
Issues found when doing mgmt tests for scenario
when Linux Kernel should do connectable advertising
while connected.
Signed-off-by: Łukasz Rymanowski <lukasz.rymanowski@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

So far, kernel did not allow to advertise when there was a connection
established. With this patch kernel does allow it if controller
supports it.

If controller supports non-connectable advertising when connected, then
only non-connectable advertising instances will be advertised.
Signed-off-by: Łukasz Rymanowski <lukasz.rymanowski@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

There is already __hci_req_disable_advertising() function for disabling,
so use it.
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

In case of using BT_ERR and BT_INFO, convert to bt_dev_err and
bt_dev_info when possible. This allows for controller specific
reporting.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

If command is added to req then it should be freed in case if
hdev is down or HCI_ADVERTISING flag is set.

This introduces a helper in hci_request to purge the cmd_q
to make cmd_q internal to hci_request which is used to fix
the leak.

This also replace accessing of cmd_q in hci_conn with the
new helper.
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>