/* miscellaneous bits
 *
 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <rxrpc/packet.h>
#include "internal.h"
#include "afs_fs.h"

/*
 * convert an AFS abort code to a Linux error number
 */
int afs_abort_to_error(u32 abort_code)
{
	switch (abort_code) {
	/* low errno codes inserted into abort namespace */
	case 13:		return -EACCES;
	case 27:		return -EFBIG;
	case 30:		return -EROFS;

	/* VICE "special error" codes; 101 - 111 */
	case VSALVAGE:		return -EIO;
	case VNOVNODE:		return -ENOENT;
	case VNOVOL:		return -ENOMEDIUM;
	case VVOLEXISTS:	return -EEXIST;
	case VNOSERVICE:	return -EIO;
	case VOFFLINE:		return -ENOENT;
	case VONLINE:		return -EEXIST;
	case VDISKFULL:		return -ENOSPC;
	case VOVERQUOTA:	return -EDQUOT;
	case VBUSY:		return -EBUSY;
	case VMOVED:		return -ENXIO;

	/* Unified AFS error table; ET "uae" == 0x2f6df00 */
	case 0x2f6df00:		return -EPERM;
	case 0x2f6df01:		return -ENOENT;
	case 0x2f6df04:		return -EIO;
	case 0x2f6df0a:		return -EAGAIN;
	case 0x2f6df0b:		return -ENOMEM;
	case 0x2f6df0c:		return -EACCES;
	case 0x2f6df0f:		return -EBUSY;
	case 0x2f6df10:		return -EEXIST;
	case 0x2f6df11:		return -EXDEV;
	case 0x2f6df12:		return -ENODEV;
	case 0x2f6df13:		return -ENOTDIR;
	case 0x2f6df14:		return -EISDIR;
	case 0x2f6df15:		return -EINVAL;
	case 0x2f6df1a:		return -EFBIG;
	case 0x2f6df1b:		return -ENOSPC;
	case 0x2f6df1d:		return -EROFS;
	case 0x2f6df1e:		return -EMLINK;
	case 0x2f6df20:		return -EDOM;
	case 0x2f6df21:		return -ERANGE;
	case 0x2f6df22:		return -EDEADLK;
	case 0x2f6df23:		return -ENAMETOOLONG;
	case 0x2f6df24:		return -ENOLCK;
	case 0x2f6df26:		return -ENOTEMPTY;
	case 0x2f6df28:		return -EWOULDBLOCK;
	case 0x2f6df69:		return -ENOTCONN;
	case 0x2f6df6c:		return -ETIMEDOUT;
	case 0x2f6df78:		return -EDQUOT;

	/* RXKAD abort codes; from include/rxrpc/packet.h.  ET "RXK" == 0x1260B00 */
	case RXKADINCONSISTENCY: return -EPROTO;
	case RXKADPACKETSHORT:	return -EPROTO;
	case RXKADLEVELFAIL:	return -EKEYREJECTED;
	case RXKADTICKETLEN:	return -EKEYREJECTED;
	case RXKADOUTOFSEQUENCE: return -EPROTO;
	case RXKADNOAUTH:	return -EKEYREJECTED;
	case RXKADBADKEY:	return -EKEYREJECTED;
	case RXKADBADTICKET:	return -EKEYREJECTED;
	case RXKADUNKNOWNKEY:	return -EKEYREJECTED;
	case RXKADEXPIRED:	return -EKEYEXPIRED;
	case RXKADSEALEDINCON:	return -EKEYREJECTED;
	case RXKADDATALEN:	return -EKEYREJECTED;
	case RXKADILLEGALLEVEL:	return -EKEYREJECTED;

	default:		return -EREMOTEIO;
	}
}
ze='10' name='q' value=''/>
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</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>drivers</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>host</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ehci-spear.c?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>ehci-spear.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='966d2b04e070bc040319aaebfec09e0144dc3341'/><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>Douglas Miller &lt;dougmill@linux.vnet.ibm.com&gt;</td><td class='right'>2017-01-28 06:42:20 -0600</td></tr>
<tr><th>committer</th><td>Tejun Heo &lt;tj@kernel.org&gt;</td><td class='right'>2017-01-28 07:49:42 -0500</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ehci-spear.c?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>966d2b04e070bc040319aaebfec09e0144dc3341</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/host/ehci-spear.c?id=966d2b04e070bc040319aaebfec09e0144dc3341'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>4b96156e3d1dd4dfd6039b7c219c9dc4616da52d</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/host/ehci-spear.c?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>drivers/usb/host/ehci-spear.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ehci-spear.c?h=nds-private-remove&amp;id=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd'>1b1bc42c1692e9b62756323c675a44cb1a1f9dbd</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/ehci-spear.c?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341&amp;id2=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd'>diff</a>)</td></tr></table>
<div class='commit-subject'>percpu-refcount: fix reference leak during percpu-atomic transition</div><div class='commit-msg'>percpu_ref_tryget() and percpu_ref_tryget_live() should return
"true" IFF they acquire a reference. But the return value from
atomic_long_inc_not_zero() is a long and may have high bits set,
e.g. PERCPU_COUNT_BIAS, and the return value of the tryget routines
is bool so the reference may actually be acquired but the routines
return "false" which results in a reference leak since the caller
assumes it does not need to do a corresponding percpu_ref_put().

This was seen when performing CPU hotplug during I/O, as hangs in
blk_mq_freeze_queue_wait where percpu_ref_kill (blk_mq_freeze_queue_start)
raced with percpu_ref_tryget (blk_mq_timeout_work).
Sample stack trace:

__switch_to+0x2c0/0x450
__schedule+0x2f8/0x970
schedule+0x48/0xc0
blk_mq_freeze_queue_wait+0x94/0x120
blk_mq_queue_reinit_work+0xb8/0x180
blk_mq_queue_reinit_prepare+0x84/0xa0
cpuhp_invoke_callback+0x17c/0x600
cpuhp_up_callbacks+0x58/0x150
_cpu_up+0xf0/0x1c0
do_cpu_up+0x120/0x150
cpu_subsys_online+0x64/0xe0
device_online+0xb4/0x120
online_store+0xb4/0xc0
dev_attr_store+0x68/0xa0
sysfs_kf_write+0x80/0xb0
kernfs_fop_write+0x17c/0x250
__vfs_write+0x6c/0x1e0
vfs_write+0xd0/0x270
SyS_write+0x6c/0x110
system_call+0x38/0xe0

Examination of the queue showed a single reference (no PERCPU_COUNT_BIAS,
and __PERCPU_REF_DEAD, __PERCPU_REF_ATOMIC set) and no requests.
However, conditions at the time of the race are count of PERCPU_COUNT_BIAS + 0
and __PERCPU_REF_DEAD and __PERCPU_REF_ATOMIC set.

The fix is to make the tryget routines use an actual boolean internally instead
of the atomic long result truncated to a int.

Fixes: e625305b3907 percpu-refcount: make percpu_ref based on longs instead of ints
Link: https://bugzilla.kernel.org/show_bug.cgi?id=190751
Signed-off-by: Douglas Miller &lt;dougmill@linux.vnet.ibm.com&gt;
Reviewed-by: Jens Axboe &lt;axboe@fb.com&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
Fixes: e625305b3907 ("percpu-refcount: make percpu_ref based on longs instead of ints")
Cc: stable@vger.kernel.org # v3.18+
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=966d2b04e070bc040319aaebfec09e0144dc3341'>Diffstat</a> (limited to 'drivers/usb/host/ehci-spear.c')</div><table summary='diffstat' class='diffstat'>