/*
* udc.h - ChipIdea UDC structures
*
* Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
*
* Author: David Lopo
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __DRIVERS_USB_CHIPIDEA_UDC_H
#define __DRIVERS_USB_CHIPIDEA_UDC_H
#include <linux/list.h>
#define CTRL_PAYLOAD_MAX 64
#define RX 0 /* similar to USB_DIR_OUT but can be used as an index */
#define TX 1 /* similar to USB_DIR_IN but can be used as an index */
/* DMA layout of transfer descriptors */
struct ci_hw_td {
/* 0 */
__le32 next;
#define TD_TERMINATE BIT(0)
#define TD_ADDR_MASK (0xFFFFFFEUL << 5)
/* 1 */
__le32 token;
#define TD_STATUS (0x00FFUL << 0)
#define TD_STATUS_TR_ERR BIT(3)
#define TD_STATUS_DT_ERR BIT(5)
#define TD_STATUS_HALTED BIT(6)
#define TD_STATUS_ACTIVE BIT(7)
#define TD_MULTO (0x0003UL << 10)
#define TD_IOC BIT(15)
#define TD_TOTAL_BYTES (0x7FFFUL << 16)
/* 2 */
__le32 page[5];
#define TD_CURR_OFFSET (0x0FFFUL << 0)
#define TD_FRAME_NUM (0x07FFUL << 0)
#define TD_RESERVED_MASK (0x0FFFUL << 0)
} __attribute__ ((packed, aligned(4)));
/* DMA layout of queue heads */
struct ci_hw_qh {
/* 0 */
__le32 cap;
#define QH_IOS BIT(15)
#define QH_MAX_PKT (0x07FFUL << 16)
#define QH_ZLT BIT(29)
#define QH_MULT (0x0003UL << 30)
#define QH_ISO_MULT(x) ((x >> 11) & 0x03)
/* 1 */
__le32 curr;
/* 2 - 8 */
struct ci_hw_td td;
/* 9 */
__le32 RESERVED;
struct usb_ctrlrequest setup;
} __attribute__ ((packed, aligned(4)));
struct td_node {
struct list_head td;
dma_addr_t dma;
struct ci_hw_td *ptr;
};
/**
* struct ci_hw_req - usb request representation
* @req: request structure for gadget drivers
* @queue: link to QH list
* @ptr: transfer descriptor for this request
* @dma: dma address for the transfer descriptor
* @zptr: transfer descriptor for the zero packet
* @zdma: dma address of the zero packet's transfer descriptor
*/
struct ci_hw_req {
struct usb_request req;
struct list_head queue;
struct list_head tds;
};
#ifdef CONFIG_USB_CHIPIDEA_UDC
int ci_hdrc_gadget_init(struct ci_hdrc *ci);
void ci_hdrc_gadget_destroy(struct ci_hdrc *ci);
#else
static inline int ci_hdrc_gadget_init(struct ci_hdrc *ci)
{
return -ENXIO;
}
static inline void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
{
}
#endif
#endif /* __DRIVERS_USB_CHIPIDEA_UDC_H */
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/fs?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>fs</a>/<a href='/cgit.cgi/linux/net-next.git/commit/fs/befs?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>befs</a>/<a href='/cgit.cgi/linux/net-next.git/commit/fs/befs/datastream.c?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>datastream.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 <dougmill@linux.vnet.ibm.com></td><td class='right'>2017-01-28 06:42:20 -0600</td></tr>
<tr><th>committer</th><td>Tejun Heo <tj@kernel.org></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/fs/befs/datastream.c?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>966d2b04e070bc040319aaebfec09e0144dc3341</a> (<a href='/cgit.cgi/linux/net-next.git/patch/fs/befs/datastream.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&id=966d2b04e070bc040319aaebfec09e0144dc3341'>4b96156e3d1dd4dfd6039b7c219c9dc4616da52d</a> /<a href='/cgit.cgi/linux/net-next.git/tree/fs/befs/datastream.c?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341'>fs/befs/datastream.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/befs/datastream.c?h=nds-private-remove&id=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd'>1b1bc42c1692e9b62756323c675a44cb1a1f9dbd</a> (<a href='/cgit.cgi/linux/net-next.git/diff/fs/befs/datastream.c?h=nds-private-remove&id=966d2b04e070bc040319aaebfec09e0144dc3341&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 <dougmill@linux.vnet.ibm.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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&id=966d2b04e070bc040319aaebfec09e0144dc3341'>Diffstat</a> (limited to 'fs/befs/datastream.c')</div><table summary='diffstat' class='diffstat'>