/*
 * Copyright (c) 2015, Sony Mobile Communications Inc.
 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/soc/qcom/smd.h>

#include "qrtr.h"

struct qrtr_smd_dev {
	struct qrtr_endpoint ep;
	struct qcom_smd_channel *channel;
	struct device *dev;
};

/* from smd to qrtr */
static int qcom_smd_qrtr_callback(struct qcom_smd_channel *channel,
				  const void *data, size_t len)
{
	struct qrtr_smd_dev *qdev = qcom_smd_get_drvdata(channel);
	int rc;

	if (!qdev)
		return -EAGAIN;

	rc = qrtr_endpoint_post(&qdev->ep, data, len);
	if (rc == -EINVAL) {
		dev_err(qdev->dev, "invalid ipcrouter packet\n");
		/* return 0 to let smd drop the packet */
		rc = 0;
	}

	return rc;
}

/* from qrtr to smd */
static int qcom_smd_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
{
	struct qrtr_smd_dev *qdev = container_of(ep, struct qrtr_smd_dev, ep);
	int rc;

	rc = skb_linearize(skb);
	if (rc)
		goto out;

	rc = qcom_smd_send(qdev->channel, skb->data, skb->len);

out:
	if (rc)
		kfree_skb(skb);
	else
		consume_skb(skb);
	return rc;
}

static int qcom_smd_qrtr_probe(struct qcom_smd_device *sdev)
{
	struct qrtr_smd_dev *qdev;
	int rc;

	qdev = devm_kzalloc(&sdev->dev, sizeof(*qdev), GFP_KERNEL);
	if (!qdev)
		return -ENOMEM;

	qdev->channel = sdev->channel;
	qdev->dev = &sdev->dev;
	qdev->ep.xmit = qcom_smd_qrtr_send;

	rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO);
	if (rc)
		return rc;

	qcom_smd_set_drvdata(sdev->channel, qdev);
	dev_set_drvdata(&sdev->dev, qdev);

	dev_dbg(&sdev->dev, "Qualcomm SMD QRTR driver probed\n");

	return 0;
}

static void qcom_smd_qrtr_remove(struct qcom_smd_device *sdev)
{
	struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);

	qrtr_endpoint_unregister(&qdev->ep);

	dev_set_drvdata(&sdev->dev, NULL);
}

static const struct qcom_smd_id qcom_smd_qrtr_smd_match[] = {
	{ "IPCRTR" },
	{}
};

static struct qcom_smd_driver qcom_smd_qrtr_driver = {
	.probe = qcom_smd_qrtr_probe,
	.remove = qcom_smd_qrtr_remove,
	.callback = qcom_smd_qrtr_callback,
	.smd_match_table = qcom_smd_qrtr_smd_match,
	.driver = {
		.name = "qcom_smd_qrtr",
		.owner = THIS_MODULE,
	},
};

module_qcom_smd_driver(qcom_smd_qrtr_driver);

MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
MODULE_LICENSE("GPL v2");
bc746ed9b415c25e92'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>drivers</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>musb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb/musb_dma.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>musb_dma.h</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='c8f325a59cfc718d13a50fbc746ed9b415c25e92'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;</td><td class='right'>2017-02-01 17:45:02 +0000</td></tr>
<tr><th>committer</th><td>Ingo Molnar &lt;mingo@kernel.org&gt;</td><td class='right'>2017-02-01 21:17:49 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb/musb_dma.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>c8f325a59cfc718d13a50fbc746ed9b415c25e92</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/musb/musb_dma.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>d53fbdac9d0781e39a13b2ac6b2bd258cf3b4140</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/musb/musb_dma.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>drivers/usb/musb/musb_dma.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb/musb_dma.h?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/musb/musb_dma.h?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92&amp;id2=bf29bddf0417a4783da3b24e8c9e017ac649326f'>diff</a>)</td></tr></table>
<div class='commit-subject'>efi/fdt: Avoid FDT manipulation after ExitBootServices()</div><div class='commit-msg'>Some AArch64 UEFI implementations disable the MMU in ExitBootServices(),
after which unaligned accesses to RAM are no longer supported.

Commit:

  abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")

fixed an issue in the memory map handling of the stub FDT code, but
inadvertently created an issue with such firmware, by moving some
of the FDT manipulation to after the invocation of ExitBootServices().

Given that the stub's libfdt implementation uses the ordinary, accelerated
string functions, which rely on hardware handling of unaligned accesses,
manipulating the FDT with the MMU off may result in alignment faults.

So fix the situation by moving the update_fdt_memmap() call into the
callback function invoked by efi_exit_boot_services() right before it
calls the ExitBootServices() UEFI service (which is arguably a better
place for it anyway)

Note that disabling the MMU in ExitBootServices() is not compliant with
the UEFI spec, and carries great risk due to the fact that switching from
cached to uncached memory accesses halfway through compiler generated code
(i.e., involving a stack) can never be done in a way that is architecturally
safe.

Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel")
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Tested-by: Riku Voipio &lt;riku.voipio@linaro.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: mark.rutland@arm.com
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: leif.lindholm@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=c8f325a59cfc718d13a50fbc746ed9b415c25e92'>Diffstat</a> (limited to 'drivers/usb/musb/musb_dma.h')</div><table summary='diffstat' class='diffstat'>