linux.git/drivers/nfc/pn533, branch v4.13

net: manual clean code which call skb_put_[data:zero]

2017-06-20T17:30:15+00:00

Signed-off-by: yuan linyu 
Signed-off-by: David S. Miller

networking: add and use skb_put_u8()

2017-06-16T15:48:40+00:00

Joe and Bjørn suggested that it'd be nicer to not have the
cast in the fairly common case of doing
	*(u8 *)skb_put(skb, 1) = c;

Add skb_put_u8() for this case, and use it across the code,
using the following spatch:

    @@
    expression SKB, C, S;
    typedef u8;
    identifier fn = {skb_put};
    fresh identifier fn2 = fn ## "_u8";
    @@
    - *(u8 *)fn(SKB, S) = C;
    + fn2(SKB, C);

Note that due to the "S", the spatch isn't perfect, it should
have checked that S is 1, but there's also places that use a
sizeof expression like sizeof(var) or sizeof(u8) etc. Turns
out that nobody ever did something like
	*(u8 *)skb_put(skb, 2) = c;

which would be wrong anyway since the second byte wouldn't be
initialized.

Suggested-by: Joe Perches 
Suggested-by: Bjørn Mork 
Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

networking: make skb_push & __skb_push return void pointers

2017-06-16T15:48:40+00:00

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 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_push, __skb_push, skb_push_rcsum };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

    @@
    expression SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - fn(SKB, LEN)[0]
    + *(u8 *)fn(SKB, LEN)

Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

networking: make skb_put & friends return void pointers

2017-06-16T15:48:39+00:00

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 
Signed-off-by: David S. Miller

networking: introduce and use skb_put_data()

2017-06-16T15:48:37+00:00

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 
Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

networking: use skb_put_zero()

2017-06-13T17:54:03+00:00

Use the recently introduced helper to replace the pattern of
skb_put() && memset(), this transformation was done with the
following spatch:

@@
identifier p;
expression len;
expression skb;
@@
-p = skb_put(skb, len);
-memset(p, 0, len);
+p = skb_put_zero(skb, len);

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

NFC: pn533: use constant off-stack buffer for sending acks

2017-04-16T22:33:31+00:00

fix for WARN:

usb 3-2.4.1: NFC: Exchanging data failed (error 0x13)
llcp: nfc_llcp_recv: err -5
llcp: nfc_llcp_symm_timer: SYMM timeout
------------[ cut here ]------------
WARNING: CPU: 1 PID: 26397 at .../drivers/usb/core/hcd.c:1584 usb_hcd_map_urb_for_dma+0x370/0x550
transfer buffer not dma capable
[...]
Workqueue: events nfc_llcp_timeout_work [nfc]
Call Trace:
 ? dump_stack+0x46/0x5a
 ? __warn+0xb9/0xe0
 ? warn_slowpath_fmt+0x5a/0x80
 ? usb_hcd_map_urb_for_dma+0x370/0x550
 ? usb_hcd_submit_urb+0x2fb/0xa60
 ? dequeue_entity+0x3f2/0xc30
 ? pn533_usb_send_ack+0x5d/0x80 [pn533_usb]
 ? pn533_usb_abort_cmd+0x13/0x20 [pn533_usb]
 ? pn533_dep_link_down+0x32/0x70 [pn533]
 ? nfc_dep_link_down+0x87/0xd0 [nfc]
[...]
usb 3-2.4.1: NFC: Exchanging data failed (error 0x13)
llcp: nfc_llcp_recv: err -5
llcp: nfc_llcp_symm_timer: SYMM timeout

Signed-off-by: Michał Mirosław 
Signed-off-by: Samuel Ortiz

NFC: pn533: change order operations in dev registation

2017-04-01T23:06:23+00:00

Sometimes during probing and registration of pn533_i2c
NULL pointer dereference happens.
Reproduced in cycle of inserting and removing pn533_i2c
and pn533 modules.

Backtrace:
[<8004205c>] (__queue_work) from [<80042324>] (queue_work_on+0x50/0x5c)
r10:acdc7c80 r9:8006b330 r8:ac0dfb40 r7:ac50c600 r6:00000004 r5:acbbee40 r4:600f0113
[<800422d4>] (queue_work_on) from [<7f7d5b6c>] (pn533_recv_frame+0x158/0x1fc [pn533])
r7:ffffff87 r6:00000000 r5:acbbee40 r4:acbbee00
[<7f7d5a14>] (pn533_recv_frame [pn533]) from [<7f7df4b8>] (pn533_i2c_irq_thread_fn+0x184/0x)
r6:acb2a000 r5:00000000 r4:acdc7b90
[<7f7df334>] (pn533_i2c_irq_thread_fn [pn533_i2c]) from [<8006b354>] (irq_thread_fn+0x24/0x)
r7:00000000 r6:accde000 r5:ac0dfb40 r4:acdc7c80
...

Seems there is some race condition due registration of
irq handler until all data stuctures that could be needed
are ready. So I re-ordered some ops. After this, problem has gone.

Changes in USB part was not tested, but it should not break
anything.

Signed-off-by: Andrey Rusalin 
Signed-off-by: Samuel Ortiz

NFC: pn533: improve cmd queue handling

2017-04-01T23:06:22+00:00

Make sure cmd is set before a frame is passed to the transport layer for
sending. In addition pn533_send_async_complete checks if cmd is set before
accessing its members.

Signed-off-by: Michael Thalmeier 

Rework a little bit changes in pn532_send_async_complete.

Signed-off-by: Andrey Rusalin 
Signed-off-by: Samuel Ortiz

NFC: pn533: change order of free_irq and dev unregistration

2017-04-01T23:06:21+00:00

Change order of free_irq and dev unregistration.
It fixes situation when device already unregistered and
an interrupt happens and nobody can handle it.

Signed-off-by: Andrey Rusalin 
Signed-off-by: Samuel Ortiz