Increase the possibilities of including at least one payload by reserving
some additional space in the TX queue while allocating TX queue's space
for new message header. Please refer the documentation in the code for details.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
This patch fixes an infinite loop caused by i2400m_tx_fifo_push() due
to a corner case where there is no tail space in the TX FIFO.
Please refer the documentation in the code for details.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
This fixes i2400m_tx_fifo_push(); the check for having enough
space in the TX FIFO's tail was obscure and broken in certain
corner cases. The new check works in all cases and is way
clearer. Please refer the documentation in the code for details.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
The older method of computing the maximum PDU size relied
on a method that doesn't work when we prop the maximum
number of payloads up to the physical limit, and thus we kill
the whole computation and just verify that the constants are
congruent.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
According to Intel Wimax i3200, i5x50 and i6x50 specification
documents, the maximum size of each TX message can be upto 16KiB.
This patch modifies the i2400m_tx() routine to check that the
message size does not exceed the 16KiB limit.
Please refer the documentation in the code for details.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
According to Intel Wimax i3200, i5x50 and i6x50 device specification
documents, the maximum number of payloads per message can be up to 60.
Increasing the number of payloads to 60 per message helps to
accommodate smaller payloads in a single transaction. This patch
increases the maximum number of payloads from 12 to 60 per message.
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
This patch makes sure whenever tx_setup() is invoked during driver
initialization or device reset where TX FIFO is released and re-allocated,
the indices tx_in, tx_out, tx_msg_size, tx_sequence, tx_msg are properly
initialized.
When a device reset happens and the TX FIFO is released/re-allocated,
a new block of memory may be allocated for the TX FIFO, therefore tx_msg
should be cleared so that no any TX threads (tx_worker, tx) would access
to the out-of-date addresses.
Also, the TX threads use tx_in and tx_out to decide where to put the new
host-to-device messages and from where to copy them to the device HW FIFO,
these indices have to be cleared so after the TX FIFO is re-allocated during
the reset, the indices both refer to the head of the FIFO, ie. a new start.
The same rational applies to tx_msg_size and tx_sequence.
To protect the indices from being accessed by multiple threads simultaneously,
the lock tx_lock has to be obtained before the initializations and released
afterwards.
Signed-off-by: Cindy H Kao <cindy.h.kao@intel.com>
This patch increases the Tx buffer size so as to accommodate 12 payloads
of 1408 (1400 MTU 16 bytes aligned). Currently Tx buffer is 32 KiB which
is insufficient to accommodate 12 payloads of 1408 size.
This patch
- increases I2400M_TX_BUF_SIZE from 32KiB to 64KiB
- Adds a BUILD_BUG_ON if the calculated buffer size based
on the given MTU exceeds the I2400M_TX_BUF_SIZE.
Below is how we calculate the size of the Tx buffer.
Payload + 4 bytes prefix for each payload (1400 MTU 16 bytes boundary aligned)
= (1408 + sizeof(struct i2400m_pl_data_hdr)) * I2400M_TX_PLD_MAX
Adding 16 byte message header = + sizeof(struct i2400m_msg_hdr)
Aligning to 256 byte boundary
Total Tx buffer = (((((1408 + sizeof(struct i2400m_pl_data_hdr))
* I2400M_TX_PLD_MAX )+ sizeof(struct i2400m_msg_hdr))
/ 256) + 1) * 256 * 2
Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
i2400m_tx() routine was returning -ESHUTDOWN even when there was no Tx buffer
available. This patch fixes the i2400m_tx() to return -ESHUTDOWN only when
the device is down(i2400m->tx_buf is NULL) and also to return -ENOSPC
when there is no Tx buffer. Error seen in the kernel log.
kernel: i2400m_sdio mmc0:0001:1: can't send message 0x5606: -108
kernel: i2400m_sdio mmc0:0001:1: Failed to issue 'Enter power save'command: -108
Signed-off-by: Prasanna S.Panchamukhi <prasannax.s.panchamukhi@intel.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
All the entry points into the TX module should check if the device has
been torn down. Otherwise, when the device resets or shuts down, there
are windows when a call to i2400m_tx*() will oops the system.
For that, make i2400m_tx_release() set i2400m->tx_buf to NULL under
the tx_lock. Then, any entry point [i2400m_tx(), _tx_msg_sent(),
_tx_msg_get()] will check for i2400m->tx_buf to be NULL and exit
gracefully.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
When the TX FIFO filled up and i2400m_tx_new() failed to allocate a
new TX message header, a missing check for said condition was causing a
kernel oops when trying to dereference a NULL i2400m->tx_msg pointer.
Found and diagnosed by Cindy H. Kao.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
i2400m_tx_skip_tail() needs to handle the special case of being called
when the tail room that is left over in the FIFO is zero.
This happens when a TX message header was opened at the very end of
the FIFO (without payloads). The i2400m_tx_close() code already marked
said TX message (header) to be skipped and this function should be
doing nothing.
It is called anyway because it is part of a common "corner case" path
handling which takes care of more cases than only this one.
The tail room computation was also improved to take care of the case
when tx_in is at the end of the buffer boundary; tail_room has to be
modded (%) to the buffer size. To do that in a single well-documented
place, __i2400m_tx_tail_room() is introduced and used.
Treat i2400m->tx_in == 0 as a corner case and handle it accordingly.
Found and diagnosed by Cindy H. Kao.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
In some situations, when a new TX message header is started, there
might be no space for data payloads. In this case the message is left
with zero payloads and the i2400m_tx_close() function has just to mark
it as "to skip". If it tries to go ahead it will overwrite things
because there is no space to add padding as defined by the
bus-specific layer. This can cause buffer overruns and in some stress
cases, panics.
Found and diagnosed by Cindy H. Kao.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
The constant is being use as an alignment factor, not as a padding
factor; made reading/reviewing the code quite confusing.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Reported and fixed by Cindy H Kao.
When the device is stopped __i2400m_dev_stop() stops the network
queue.
However, when this is done in the middle of heavy network operation,
when the bus-specific subdriver is still wrapping up and it reports a
sent TX transaction with _tx_msg_sent() right after the device was
stopped, the queue was being started again, which was causing a stream
of oopsen and finally a panic.
In any case, said call has no place there. It's a left over from an
early implementation that was discarded later on.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Handling of TX/RX data to/from the i2400m device (IP packets, control
and diagnostics). On RX, this parses the received read transaction
from the device, breaks it in chunks and passes it to the
corresponding subsystems (network and control).
Transmission to the device is done through a software FIFO, as
data/control frames can be coalesced (while the device is reading the
previous tx transaction, others accumulate). A FIFO is used because at
the end it is resource-cheaper that scatter/gather over USB. As well,
most traffic is going to be download (vs upload).
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Prasanna S. Panchamukhi