kernel-ark/drivers/uwb/est.c
Thomas Meyer a451eaf9c5 uwb: Use kcalloc instead of kzalloc to allocate array
The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-09 16:18:20 -08:00

468 lines
13 KiB
C

/*
* Ultra Wide Band Radio Control
* Event Size Tables management
*
* Copyright (C) 2005-2006 Intel Corporation
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
*
* 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.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* FIXME: docs
*
* Infrastructure, code and data tables for guessing the size of
* events received on the notification endpoints of UWB radio
* controllers.
*
* You define a table of events and for each, its size and how to get
* the extra size.
*
* ENTRY POINTS:
*
* uwb_est_{init/destroy}(): To initialize/release the EST subsystem.
*
* uwb_est_[u]register(): To un/register event size tables
* uwb_est_grow()
*
* uwb_est_find_size(): Get the size of an event
* uwb_est_get_size()
*/
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/export.h>
#include "uwb-internal.h"
struct uwb_est {
u16 type_event_high;
u16 vendor, product;
u8 entries;
const struct uwb_est_entry *entry;
};
static struct uwb_est *uwb_est;
static u8 uwb_est_size;
static u8 uwb_est_used;
static DEFINE_RWLOCK(uwb_est_lock);
/**
* WUSB Standard Event Size Table, HWA-RC interface
*
* Sizes for events and notifications type 0 (general), high nibble 0.
*/
static
struct uwb_est_entry uwb_est_00_00xx[] = {
[UWB_RC_EVT_IE_RCV] = {
.size = sizeof(struct uwb_rc_evt_ie_rcv),
.offset = 1 + offsetof(struct uwb_rc_evt_ie_rcv, wIELength),
},
[UWB_RC_EVT_BEACON] = {
.size = sizeof(struct uwb_rc_evt_beacon),
.offset = 1 + offsetof(struct uwb_rc_evt_beacon, wBeaconInfoLength),
},
[UWB_RC_EVT_BEACON_SIZE] = {
.size = sizeof(struct uwb_rc_evt_beacon_size),
},
[UWB_RC_EVT_BPOIE_CHANGE] = {
.size = sizeof(struct uwb_rc_evt_bpoie_change),
.offset = 1 + offsetof(struct uwb_rc_evt_bpoie_change,
wBPOIELength),
},
[UWB_RC_EVT_BP_SLOT_CHANGE] = {
.size = sizeof(struct uwb_rc_evt_bp_slot_change),
},
[UWB_RC_EVT_BP_SWITCH_IE_RCV] = {
.size = sizeof(struct uwb_rc_evt_bp_switch_ie_rcv),
.offset = 1 + offsetof(struct uwb_rc_evt_bp_switch_ie_rcv, wIELength),
},
[UWB_RC_EVT_DEV_ADDR_CONFLICT] = {
.size = sizeof(struct uwb_rc_evt_dev_addr_conflict),
},
[UWB_RC_EVT_DRP_AVAIL] = {
.size = sizeof(struct uwb_rc_evt_drp_avail)
},
[UWB_RC_EVT_DRP] = {
.size = sizeof(struct uwb_rc_evt_drp),
.offset = 1 + offsetof(struct uwb_rc_evt_drp, ie_length),
},
[UWB_RC_EVT_BP_SWITCH_STATUS] = {
.size = sizeof(struct uwb_rc_evt_bp_switch_status),
},
[UWB_RC_EVT_CMD_FRAME_RCV] = {
.size = sizeof(struct uwb_rc_evt_cmd_frame_rcv),
.offset = 1 + offsetof(struct uwb_rc_evt_cmd_frame_rcv, dataLength),
},
[UWB_RC_EVT_CHANNEL_CHANGE_IE_RCV] = {
.size = sizeof(struct uwb_rc_evt_channel_change_ie_rcv),
.offset = 1 + offsetof(struct uwb_rc_evt_channel_change_ie_rcv, wIELength),
},
[UWB_RC_CMD_CHANNEL_CHANGE] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_DEV_ADDR_MGMT] = {
.size = sizeof(struct uwb_rc_evt_dev_addr_mgmt) },
[UWB_RC_CMD_GET_IE] = {
.size = sizeof(struct uwb_rc_evt_get_ie),
.offset = 1 + offsetof(struct uwb_rc_evt_get_ie, wIELength),
},
[UWB_RC_CMD_RESET] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SCAN] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SET_BEACON_FILTER] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SET_DRP_IE] = {
.size = sizeof(struct uwb_rc_evt_set_drp_ie),
},
[UWB_RC_CMD_SET_IE] = {
.size = sizeof(struct uwb_rc_evt_set_ie),
},
[UWB_RC_CMD_SET_NOTIFICATION_FILTER] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SET_TX_POWER] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SLEEP] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_START_BEACON] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_STOP_BEACON] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_BP_MERGE] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SEND_COMMAND_FRAME] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
[UWB_RC_CMD_SET_ASIE_NOTIF] = {
.size = sizeof(struct uwb_rc_evt_confirm),
},
};
static
struct uwb_est_entry uwb_est_01_00xx[] = {
[UWB_RC_DAA_ENERGY_DETECTED] = {
.size = sizeof(struct uwb_rc_evt_daa_energy_detected),
},
[UWB_RC_SET_DAA_ENERGY_MASK] = {
.size = sizeof(struct uwb_rc_evt_set_daa_energy_mask),
},
[UWB_RC_SET_NOTIFICATION_FILTER_EX] = {
.size = sizeof(struct uwb_rc_evt_set_notification_filter_ex),
},
};
/**
* Initialize the EST subsystem
*
* Register the standard tables also.
*
* FIXME: tag init
*/
int uwb_est_create(void)
{
int result;
uwb_est_size = 2;
uwb_est_used = 0;
uwb_est = kcalloc(uwb_est_size, sizeof(uwb_est[0]), GFP_KERNEL);
if (uwb_est == NULL)
return -ENOMEM;
result = uwb_est_register(UWB_RC_CET_GENERAL, 0, 0xffff, 0xffff,
uwb_est_00_00xx, ARRAY_SIZE(uwb_est_00_00xx));
if (result < 0)
goto out;
result = uwb_est_register(UWB_RC_CET_EX_TYPE_1, 0, 0xffff, 0xffff,
uwb_est_01_00xx, ARRAY_SIZE(uwb_est_01_00xx));
out:
return result;
}
/** Clean it up */
void uwb_est_destroy(void)
{
kfree(uwb_est);
uwb_est = NULL;
uwb_est_size = uwb_est_used = 0;
}
/**
* Double the capacity of the EST table
*
* @returns 0 if ok, < 0 errno no error.
*/
static
int uwb_est_grow(void)
{
size_t actual_size = uwb_est_size * sizeof(uwb_est[0]);
void *new = kmalloc(2 * actual_size, GFP_ATOMIC);
if (new == NULL)
return -ENOMEM;
memcpy(new, uwb_est, actual_size);
memset(new + actual_size, 0, actual_size);
kfree(uwb_est);
uwb_est = new;
uwb_est_size *= 2;
return 0;
}
/**
* Register an event size table
*
* Makes room for it if the table is full, and then inserts it in the
* right position (entries are sorted by type, event_high, vendor and
* then product).
*
* @vendor: vendor code for matching against the device (0x0000 and
* 0xffff mean any); use 0x0000 to force all to match without
* checking possible vendor specific ones, 0xfffff to match
* after checking vendor specific ones.
*
* @product: product code from that vendor; same matching rules, use
* 0x0000 for not allowing vendor specific matches, 0xffff
* for allowing.
*
* This arragement just makes the tables sort differenty. Because the
* table is sorted by growing type-event_high-vendor-product, a zero
* vendor will match before than a 0x456a vendor, that will match
* before a 0xfffff vendor.
*
* @returns 0 if ok, < 0 errno on error (-ENOENT if not found).
*/
/* FIXME: add bus type to vendor/product code */
int uwb_est_register(u8 type, u8 event_high, u16 vendor, u16 product,
const struct uwb_est_entry *entry, size_t entries)
{
unsigned long flags;
unsigned itr;
u16 type_event_high;
int result = 0;
write_lock_irqsave(&uwb_est_lock, flags);
if (uwb_est_used == uwb_est_size) {
result = uwb_est_grow();
if (result < 0)
goto out;
}
/* Find the right spot to insert it in */
type_event_high = type << 8 | event_high;
for (itr = 0; itr < uwb_est_used; itr++)
if (uwb_est[itr].type_event_high < type
&& uwb_est[itr].vendor < vendor
&& uwb_est[itr].product < product)
break;
/* Shift others to make room for the new one? */
if (itr < uwb_est_used)
memmove(&uwb_est[itr+1], &uwb_est[itr], uwb_est_used - itr);
uwb_est[itr].type_event_high = type << 8 | event_high;
uwb_est[itr].vendor = vendor;
uwb_est[itr].product = product;
uwb_est[itr].entry = entry;
uwb_est[itr].entries = entries;
uwb_est_used++;
out:
write_unlock_irqrestore(&uwb_est_lock, flags);
return result;
}
EXPORT_SYMBOL_GPL(uwb_est_register);
/**
* Unregister an event size table
*
* This just removes the specified entry and moves the ones after it
* to fill in the gap. This is needed to keep the list sorted; no
* reallocation is done to reduce the size of the table.
*
* We unregister by all the data we used to register instead of by
* pointer to the @entry array because we might have used the same
* table for a bunch of IDs (for example).
*
* @returns 0 if ok, < 0 errno on error (-ENOENT if not found).
*/
int uwb_est_unregister(u8 type, u8 event_high, u16 vendor, u16 product,
const struct uwb_est_entry *entry, size_t entries)
{
unsigned long flags;
unsigned itr;
struct uwb_est est_cmp = {
.type_event_high = type << 8 | event_high,
.vendor = vendor,
.product = product,
.entry = entry,
.entries = entries
};
write_lock_irqsave(&uwb_est_lock, flags);
for (itr = 0; itr < uwb_est_used; itr++)
if (!memcmp(&uwb_est[itr], &est_cmp, sizeof(est_cmp)))
goto found;
write_unlock_irqrestore(&uwb_est_lock, flags);
return -ENOENT;
found:
if (itr < uwb_est_used - 1) /* Not last one? move ones above */
memmove(&uwb_est[itr], &uwb_est[itr+1], uwb_est_used - itr - 1);
uwb_est_used--;
write_unlock_irqrestore(&uwb_est_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(uwb_est_unregister);
/**
* Get the size of an event from a table
*
* @rceb: pointer to the buffer with the event
* @rceb_size: size of the area pointed to by @rceb in bytes.
* @returns: > 0 Size of the event
* -ENOSPC An area big enough was not provided to look
* ahead into the event's guts and guess the size.
* -EINVAL Unknown event code (wEvent).
*
* This will look at the received RCEB and guess what is the total
* size. For variable sized events, it will look further ahead into
* their length field to see how much data should be read.
*
* Note this size is *not* final--the neh (Notification/Event Handle)
* might specificy an extra size to add.
*/
static
ssize_t uwb_est_get_size(struct uwb_rc *uwb_rc, struct uwb_est *est,
u8 event_low, const struct uwb_rceb *rceb,
size_t rceb_size)
{
unsigned offset;
ssize_t size;
struct device *dev = &uwb_rc->uwb_dev.dev;
const struct uwb_est_entry *entry;
size = -ENOENT;
if (event_low >= est->entries) { /* in range? */
dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: event %u out of range\n",
est, est->type_event_high, est->vendor, est->product,
est->entries, event_low);
goto out;
}
size = -ENOENT;
entry = &est->entry[event_low];
if (entry->size == 0 && entry->offset == 0) { /* unknown? */
dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: event %u unknown\n",
est, est->type_event_high, est->vendor, est->product,
est->entries, event_low);
goto out;
}
offset = entry->offset; /* extra fries with that? */
if (offset == 0)
size = entry->size;
else {
/* Ops, got an extra size field at 'offset'--read it */
const void *ptr = rceb;
size_t type_size = 0;
offset--;
size = -ENOSPC; /* enough data for more? */
switch (entry->type) {
case UWB_EST_16: type_size = sizeof(__le16); break;
case UWB_EST_8: type_size = sizeof(u8); break;
default: BUG();
}
if (offset + type_size > rceb_size) {
dev_err(dev, "EST %p 0x%04x/%04x/%04x[%u]: "
"not enough data to read extra size\n",
est, est->type_event_high, est->vendor,
est->product, est->entries);
goto out;
}
size = entry->size;
ptr += offset;
switch (entry->type) {
case UWB_EST_16: size += le16_to_cpu(*(__le16 *)ptr); break;
case UWB_EST_8: size += *(u8 *)ptr; break;
default: BUG();
}
}
out:
return size;
}
/**
* Guesses the size of a WA event
*
* @rceb: pointer to the buffer with the event
* @rceb_size: size of the area pointed to by @rceb in bytes.
* @returns: > 0 Size of the event
* -ENOSPC An area big enough was not provided to look
* ahead into the event's guts and guess the size.
* -EINVAL Unknown event code (wEvent).
*
* This will look at the received RCEB and guess what is the total
* size by checking all the tables registered with
* uwb_est_register(). For variable sized events, it will look further
* ahead into their length field to see how much data should be read.
*
* Note this size is *not* final--the neh (Notification/Event Handle)
* might specificy an extra size to add or replace.
*/
ssize_t uwb_est_find_size(struct uwb_rc *rc, const struct uwb_rceb *rceb,
size_t rceb_size)
{
/* FIXME: add vendor/product data */
ssize_t size;
struct device *dev = &rc->uwb_dev.dev;
unsigned long flags;
unsigned itr;
u16 type_event_high, event;
u8 *ptr = (u8 *) rceb;
read_lock_irqsave(&uwb_est_lock, flags);
size = -ENOSPC;
if (rceb_size < sizeof(*rceb))
goto out;
event = le16_to_cpu(rceb->wEvent);
type_event_high = rceb->bEventType << 8 | (event & 0xff00) >> 8;
for (itr = 0; itr < uwb_est_used; itr++) {
if (uwb_est[itr].type_event_high != type_event_high)
continue;
size = uwb_est_get_size(rc, &uwb_est[itr],
event & 0x00ff, rceb, rceb_size);
/* try more tables that might handle the same type */
if (size != -ENOENT)
goto out;
}
dev_dbg(dev, "event 0x%02x/%04x/%02x: no handlers available; "
"RCEB %02x %02x %02x %02x\n",
(unsigned) rceb->bEventType,
(unsigned) le16_to_cpu(rceb->wEvent),
(unsigned) rceb->bEventContext,
ptr[0], ptr[1], ptr[2], ptr[3]);
size = -ENOENT;
out:
read_unlock_irqrestore(&uwb_est_lock, flags);
return size;
}
EXPORT_SYMBOL_GPL(uwb_est_find_size);