Commit Graph

458 Commits

Author SHA1 Message Date
Pankaj Bharadiya c593642c8b treewide: Use sizeof_field() macro
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

	if [[ "$file" =~ $EXCLUDE_FILES ]]; then
		continue
	fi
	sed -i  -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
2019-12-09 10:36:44 -08:00
Julian Wiedmann f9e50b02a9 s390/qeth: fix dangling IO buffers after halt/clear
The cio layer's intparm logic does not align itself well with how qeth
manages cmd IOs. When an active IO gets terminated via halt/clear, the
corresponding IRQ's intparm does not reflect the cmd buffer but rather
the intparm that was passed to ccw_device_halt() / ccw_device_clear().
This behaviour was recently clarified in
commit b91d9e67e5 ("s390/cio: fix intparm documentation").

As a result, qeth_irq() currently doesn't cancel a cmd that was
terminated via halt/clear. This primarily causes us to leak
card->read_cmd after the qeth device is removed, since our IO path still
holds a refcount for this cmd.

For qeth this means that we need to keep track of which IO is pending on
a device ('active_cmd'), and use this as the intparm when calling
halt/clear. Otherwise qeth_irq() can't match the subsequent IRQ to its
cmd buffer.
Since we now keep track of the _expected_ intparm, we can also detect
any mismatch; this would constitute a bug somewhere in the lower layers.
In this case cancel the active cmd - we effectively "lost" the IRQ and
should not expect any further notification for this IO.

Fixes: 405548959c ("s390/qeth: add support for dynamically allocated cmds")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-05 12:25:05 -08:00
Julian Wiedmann f677fcb9ae s390/qeth: ensure linear access to packet headers
When the RX path builds non-linear skbs, the packet headers can
currently spill over into page fragments. Depending on the packet type
and what fields we need to access in the headers, this could cause us
to go past the end of skb->data.

So for non-linear packets, copy precisely the length of the necessary
headers ('linear_len') into skb->data.
And don't copy more, upper-level protocols will peel whatever additional
packet headers they need.

Fixes: 4a71df5004 ("qeth: new qeth device driver")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-05 12:25:05 -08:00
Julian Wiedmann 5b55633f20 s390/qeth: guard against runt packets
Depending on a packet's type, the RX path needs to access fields in the
packet headers and thus requires a minimum packet length.
Enforce this length when building the skb.

On the other hand a single runt packet is no reason to drop the whole
RX buffer. So just skip it, and continue processing on the next packet.

Fixes: 4a71df5004 ("qeth: new qeth device driver")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-05 12:25:05 -08:00
Jakub Kicinski a9f852e92e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock
from commit c8183f5489 ("s390/qeth: fix potential deadlock on
workqueue flush"), removed the code which was removed by commit
9897d583b0 ("s390/qeth: consolidate some duplicated HW cmd code").

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-11-22 16:27:24 -08:00
Julian Wiedmann 2f3c269d96 s390/qeth: return proper errno on IO error
When propagating IO errors back to userspace, one error path in
qeth_irq() currently returns '1' instead of a proper errno.

Fixes: 54daaca702 ("s390/qeth: cancel cmd on early error")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-20 12:29:47 -08:00
Julian Wiedmann 8311c7a252 s390/qeth: clean up error path in qeth_core_probe_device()
qeth_core_free_card() is meant to be the counterpart of
qeth_alloc_card() - but unfortunately was also picked as the place
to free the QDIO queues.

This gets messy when qeth_core_probe_device() fails during
qeth_add_dbf_entry(). At this point the card->qdio.state is not initialized
yet, so qeth_free_qdio_queues() ends up operating on uninitialized data.

Luckily for now, the whole qeth_card struct is zero-allocated and the value
of the QETH_QDIO_UNINITIALIZED enum is 0 as well. So there's no real impact
from this bug at the moment, it's just really fragile.

Clean this up by moving the qeth_free_qdio_queues() call up one level in
the hierarchy. This way it doesn't get called from the error path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:16:51 -08:00
Julian Wiedmann 17caeaa476 s390/qeth: handle skb allocation error gracefully
When current code fails to allocate an skb in the RX path, it drops the
whole RX buffer. Considering the large number of packets that a single
RX buffer might contain, this is quite drastic.

Skip over the packet instead, and try to extract the next packet from
the RX buffer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:16:51 -08:00
Julian Wiedmann 7d4faee7c6 s390/qeth: drop unwanted packets earlier in RX path
Packets with an unexpected HW format are currently first extracted from
the RX buffer, passed upwards to the layer-specific driver and only then
finally dropped.

Enhance the RX path so that we can drop such packets before even
allocating an skb. For this, add some additional logic so that when a
packet is meant to be dropped, we can still walk along the packet's data
chunks in the RX buffer. This allows us to extract the following
packet(s) from the buffer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:16:51 -08:00
Julian Wiedmann 5fd3fcbb8a s390/qeth: support per-frame invalidation
Each RX buffer may contain up to 64KB worth of data. In case the device
needs to discard a packet _after_ already having reserved space for it
in the buffer, the whole buffer gets set to ERROR state. As the buffer
might contain any number of good packets, this can result in collateral
packet loss.

qeth can provide relief by enabling per-frame invalidation. The RX
buffer is then presented as usual, we just need to spot & drop any
individual packet that was flagged as invalid.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:16:50 -08:00
Julian Wiedmann 845ef9047b s390/qeth: gather more detailed RX dropped/error statistics
Where available, use the fine-grained counters in rtnl_link_stats64 to
indicate different RX error causes. For drop reasons, use driver-private
ethtool counters.

In particular this patch allows us to keep track of driver-side drops due
to unknown/unsupported HW descriptor format.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:16:50 -08:00
Julian Wiedmann 04fa55fe07 s390/qeth: don't set card state in qeth_qdio_clear_card()
Any change to the card state should only be driven by
qeth_l?_set_online() and qeth_l?_stop_card().

qeth_qdio_clear_card() currently also gets called from
(a) qeth_core_shutdown(), where we haven't walked through the whole
    teardown sequence. So changing the state to DOWN is not accurate.
(b) qeth_core_hardsetup_card(), which is only called while the card is
    still in DOWN state. No change in behaviour here.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 12:32:59 -07:00
Julian Wiedmann 9897d583b0 s390/qeth: consolidate some duplicated HW cmd code
When setting a device online, both subdrivers have the same code to
program the HW trap and Isolation mode. Move that code into a single
place.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 12:32:59 -07:00
Julian Wiedmann f9ce416ac7 s390/qeth: keep IRQ disabled until NAPI is really done
When napi_complete_done() returns false, the NAPI instance is still
active and we can keep the IRQ disabled a little longer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 12:32:59 -07:00
Julian Wiedmann ec2b559d68 s390/qeth: use QDIO_BUFNR()
qdio.h recently gained a new helper macro that handles wrap-around on a
QDIO queue, consistently use it across all of qeth.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 12:32:59 -07:00
Julian Wiedmann 8b664cd127 s390/qeth: use IQD Multi-Write
For IQD devices with Multi-Write support, we can defer the queue-flush
further and transmit multiple IO buffers with a single TX doorbell.
The same-target restriction still applies.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-31 12:32:59 -07:00
Julian Wiedmann 9f494438d4 s390/qdio: clarify size of the QIB parm area
The QIB parm area is 128 bytes long. Current code consistently misuses
an _entirely unrelated_ QDIO constant, merely because it has the same
value. Stop doing so.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-01 09:41:36 +02:00
David S. Miller 68aaf44595 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor conflict in r8169, bug fix had two versions in net
and net-next, take the net-next hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-27 14:23:31 -07:00
Julian Wiedmann 9549d70a2d s390/qeth: add xmit_more support for IQD devices
IQD devices offer limited support for bulking: all frames in a TX buffer
need to have the same target. qeth_iqd_may_bulk() implements this
constraint, and allows us to defer the TX doorbell until
(a) the buffer is full (since each buffer needs its own doorbell), or
(b) the entire TX queue is full, or
(b) we reached the BQL limit.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:39:19 -07:00
Julian Wiedmann 96bd6c94bd s390/qeth: add BQL support for IQD devices
Each TX buffer may contain multiple skbs. So just accumulate the sent
byte count in the buffer struct, and later use the same count when
completing the buffer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:39:19 -07:00
Julian Wiedmann 85e537d8f1 s390/qeth: when in TX NAPI mode, use napi_consume_skb()
This allows the stack to bulk-free our TX-completed skbs.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:39:19 -07:00
Julian Wiedmann e53edf743d s390/qeth: add TX NAPI support for IQD devices
Due to their large MTU and potentially low utilization of TX buffers,
IQD devices in particular require fast TX recycling. This makes them
a prime candidate for a TX NAPI path in qeth.

qeth_tx_poll() uses the recently introduced qdio_inspect_queue() helper
to poll the TX queue for completed buffers. To avoid hogging the CPU for
too long, we yield to the stack after completing an entire queue's worth
of buffers.
While IQD is expected to transfer its buffers synchronously (and thus
doesn't support TX interrupts), a timer covers for the odd case where a
TX buffer doesn't complete synchronously. Currently this timer should
only ever fire for
(1) the mcast queue,
(2) the occasional race, where the NAPI poll code observes an update to
    queue->used_buffers while the TX doorbell hasn't been issued yet.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:39:18 -07:00
Julian Wiedmann eeac0e20a1 s390/qeth: collect accurate TX statistics
This consolidates the SW statistics code, and improves it to
(1) account for the header overhead of each segment on a TSO skb,
(2) count dangling packets as in-error (during eg. shutdown), and
(3) only count offloads when the skb was successfully transmitted.

We also count each segment of an TSO skb as one packet - except for
tx_dropped, to be consistent with dev->tx_dropped.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:39:18 -07:00
Julian Wiedmann 292a50e3fc s390/qeth: reject oversized SNMP requests
Commit d4c08afafa ("s390/qeth: streamline SNMP cmd code") removed
the bounds checking for req_len, under the assumption that the check in
qeth_alloc_cmd() would suffice.

But that code path isn't sufficiently robust to handle a user-provided
data_length, which could overflow (when adding the cmd header overhead)
before being checked against QETH_BUFSIZE. We end up allocating just a
tiny iob, and the subsequent copy_from_user() writes past the end of
that iob.

Special-case this path and add a coarse bounds check, to protect against
maliciuous requests. This let's the subsequent code flow do its normal
job and precise checking, without risk of overflow.

Fixes: d4c08afafa ("s390/qeth: streamline SNMP cmd code")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24 16:34:08 -07:00
Julian Wiedmann 59b757a9bf s390/qeth: streamline control code for promisc mode
We have logic to determine the desired promisc mode in _each_ code path.
Change things around so that there is a clean split between
(a) high-level code that selects the new mode, and (b) implementations
of the various mechanisms to program this mode.

This also keeps qeth_promisc_to_bridge() from polluting the debug logs
on each RX modeset.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
Julian Wiedmann 308946b074 s390/qeth: merge qeth_reply struct into qeth_cmd_buffer
Except for card->read_cmd, every cmd we issue now passes through
qeth_send_control_data() and allocates a qeth_reply struct. The way we
use this struct requires additional refcounting, and pointer tracking.

Clean up things by moving most of qeth_reply's content into the main
cmd struct. This keeps things in one place, saves us the additional
refcounting and simplifies the overall code flow.
A nice little benefit is that we can now match incoming replies against
the pending requests themselves, without caching the requests' seqnos.

The qeth_reply struct stays around for a little bit longer in a shrunk
form, to avoid touching every single callback.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
Julian Wiedmann 32e85a0d83 s390/qeth: keep cmd alive after IO completion
Current code releases the cmd struct after its initial IO has completed.
Any reply processing is done independently, using a separate qeth_reply
struct.
In preparation for merging the cmd and reply structs together, take an
additional reference on the cmd object so that it stays around all the
way until qeth_send_control_data() returns.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
Julian Wiedmann 7c5f8ffb33 s390/qeth: use correct length field in SNMP cmd callback
qeth_snmp_command_cb() is the only cmd callback that pulls the reply's
data length from a low-level transport header field. This requires
additional complexity (ie. reply->offset) to make the header accessible
to what is supposed to be a pure IPA cmd callback.

Adapter cmds have a length field in their sub-cmd header, get the data
length from there instead.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
Julian Wiedmann 12fc286f84 s390/qeth: propagate length of processed cmd IO data to callback
When an cmd IO completes in qeth_irq(), calculate how much data was
processed by the device and pass this value to the cmd's callback.

This allows cmds that retrieve data from the device to check whether
sufficient data was received, so we do that in qeth_read_conf_data_cb().

Suggested-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
Julian Wiedmann afc1f67b99 s390/qeth: use node_descriptor struct
Rather than fumbling with hard-coded offsets, use the proper struct to
access the retrieved RCD information.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-20 13:51:46 -07:00
David S. Miller 446bf64b61 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge conflict of mlx5 resolved using instructions in merge
commit 9566e650bf.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-19 11:54:03 -07:00
Julian Wiedmann 072f794000 s390/qeth: serialize cmd reply with concurrent timeout
Callbacks for a cmd reply run outside the protection of card->lock, to
allow for additional cmds to be issued & enqueued in parallel.

When qeth_send_control_data() bails out for a cmd without having
received a reply (eg. due to timeout), its callback may concurrently be
processing a reply that just arrived. In this case, the callback
potentially accesses a stale reply->reply_param area that eg. was
on-stack and has already been released.

To avoid this race, add some locking so that qeth_send_control_data()
can (1) wait for a concurrently running callback, and (2) zap any
pending callback that still wants to run.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-08-13 19:26:47 -07:00
Matthew Wilcox (Oracle) d7840976e3 net: Use skb accessors in network drivers
In preparation for unifying the skb_frag and bio_vec, use the fine
accessors which already exist and use skb_frag_t instead of
struct skb_frag_struct.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-22 20:47:56 -07:00
Julian Wiedmann eca1d5c22d s390/qeth: move cast type selection into fill_header()
The cast type currently gets selected in .ndo_start_xmit, and is then
piped through several layers until it's stored into the HW header.
Push the selection down into qeth_l?_fill_header() to (1) reduce the
number of xmit-wide parameters, and (2) merge the two route validation
checks into just one.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann c4733c32ca s390/qeth: consolidate pm code
De-duplicate the pm callback implementations from the two sub-drivers,
replacing them with core helpers that delegate to the .set_online and
.set_offline callbacks.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:24 -07:00
Julian Wiedmann d4c08afafa s390/qeth: streamline SNMP cmd code
Apply some cleanups to qeth_snmp_command() and its callback:
1. when accessing the user data, use the proper struct instead of
   hard-coded offsets. Also copy the request data straight into the
   allocated cmd, skipping the extra memdup_user() to a tmp buffer.
2. capping the request length is no longer needed, the same check gets
   applied at a base level in qeth_alloc_cmd().
3. clean up some duplicated (and misindented) trace statements.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann c3b2218d31 s390/qeth: remove static cmd buffer infrastructure
Now that all cmds are dynamically allocated, the code for static cmd
buffers can go away entirely. Resulting in a nice reduction of
code/data size & complexity, while removing the risk that
qeth_clear_cmd_buffers() releases cmds that are still in-flight.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann f19f8fd2df s390/qeth: dynamically allocate MPC cmds
The base MPC cmds are the last remaining user of the static cmd buffers.
Port them over to use dynamic allocation, and stop backing the write
channel's cmd buffers with pages.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann 5cfbe10a00 s390/qeth: dynamically allocate diag cmds
Add a new wrapper that allocates DIAG cmds of the right size, and fills
in the common fields.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann b9150461e5 s390/qeth: dynamically allocate various cmds with sub-types
This patch converts the adapter, assist and bridgeport cmd paths to
dynamic allocation. Most of the work is about re-organizing the cmd
headers, calculating the correct cmd length, and filling in the right
value in the sub-cmd's length field.

Since we now also set the correct length for cmds that are not reflected
by a fixed struct (ie SNMP), we can remove the work-around from
qeth_snmp_command().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann 1c696c896f s390/qeth: clarify parameter for simple assist cmds
For code that uses qeth_send_simple_setassparms_prot(), we currently
can't differentiate whether the cmd should contain (1) no parameter, or
(2) a 4-byte parameter with value 0.
At the moment this doesn't cause any trouble. But when using dynamically
allocated cmds, we need to know whether to allocate & transmit an
additional 4 bytes of zeroes.
So instead of the raw parameter value, pass a parameter pointer
(or NULL) to qeth_send_simple_setassparms_prot().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann a59d121da2 s390/qeth: dynamically allocate simple IPA cmds
This patch reduces the usage of the write channel's static cmd buffers,
by dynamically allocating all simple IPA cmds (eg. STARTLAN, SETVMAC).
It also converts the OSN path.

Doing so requires some changes to how we calculate the cmd length.
Currently when building IPA cmds, we're quite generous in how much data
we send down to the device (basically the size of the biggest cmd we
know). This is no real concern at the moment, since the static cmd
buffers are backed with zeroed pages. But for dynamic allocations, the
exact length matters. So this patch also adds the needed length
calculations to each cmd path.

Commands that have multiple subtypes (eg. SETADP) of differing length
will be converted with follow-up patches.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27 10:18:23 -07:00
Julian Wiedmann d9b9f40bba s390/qeth: allocate a single cmd on read channel
We statically allocate 8 cmd buffers on the read channel, when the only
IO left that's still using them is the long-running READ.
Replace this with a single allocated cmd, that gets restarted whenever
the READ completed.

This introduces refcounting for allocated cmds, so that the READ cmd can
survive the IO completion.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:32 -07:00
Julian Wiedmann f3b783b1d0 s390/qeth: command-chain the IDX sequence
The current IDX sequence first sends one WRITE cmd to activate the
device, and then sends a second cmd that READs the response.

Using qeth_alloc_cmd(), we can combine this into a single IO with two
command-chained CCWs.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann 2066e1db9e s390/qeth: convert RCD code to common IO infrastructure
The RCD code is the last remaining IO path that doesn't use the
qeth_send_control_data() infrastructure. Doing so allows us to remove
all sorts of custom state machinery and logic in the IRQ handler.

Instead of introducing statically allocated cmd buffers for this single
IO on the data channel, use the new qeth_alloc_cmd() helper.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann 405548959c s390/qeth: add support for dynamically allocated cmds
qeth currently uses a fixed set of statically allocated cmd buffers for
the read and write IO channels. This (1) doesn't play well with the single
RCD cmd we need to issue on the data channel, (2) doesn't provide the
necessary flexibility for certain IDX improvements, and (3) is also rather
wasteful since the buffers are idle most of the time.

Add a new type of cmd buffer that is dynamically allocated, and keeps
its ccw chain in the DMA data area. Since this touches most callers of
qeth_setup_ccw(), also add a new CCW flags parameter for future usage.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann fcda7f73b6 s390/qeth: remove 'channel' parameter from callbacks
Each cmd buffer maintains a pointer to the IO channel that it was/will
be issued on. So when dealing with cmd buffers, we don't need to pass
around a separate channel pointer.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann 57a688aa22 s390/qeth: convert device-specific trace entries
The vast majority of SETUP-classified trace entries can be moved to
their device-specific trace file. This reduces pollution of the global
SETUP file, and provides a consistent trace view of all activity on the
device.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann 0ce37ec297 s390/qeth: remove OSN-specific IO code
OSN currently provides a custom code path to submit IPA cmds, without
waiting for the cmd response. Replace it with qeth_send_ipa_cmd(), which
uses the common qeth_send_control_data() IO infrastructure.

By setting a custom iob->callback, we can now provide feedback to the
caller about whether the cmd has been successfully submitted to HW.
Since the callback then immediately wakes up the reply-waiter object, we
maintain the old behaviour of returning early without waiting for the
response.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00
Julian Wiedmann 1273a80014 s390/qeth: remove qeth_wait_for_buffer()
The basic MPC initialization sequence is strictly sequential, and
waiting for an available cmd buffer should never be necessary.
So this change only affects the OSN path, where dangling waiters on an
unbounded wait_event() are not desirable. Switch to qeth_get_buffers(),
and let OSN callers deal with -ENOMEM.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-13 22:39:31 -07:00