Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
comedi: add comedi_check_request_region()
There is an existing comedi_request_region(dev, start, len) function
used by COMEDI drivers for legacy devices to request an I/O port region
starting at a specified base address (which must be non-zero) and with a
specified length. It uses request_region(). On success, it sets
dev->iobase and dev->iolen and returns 0. There is a alternative
function __comedi_request_region(dev, start, len) which does the same
thing without setting dev->iobase and dev->iolen.
Most hardware devices have restrictions on the allowed I/O port base
address and alignment, so add new functions
comedi_check_request_region(dev, start, len, minstart, maxend, minalign)
and __comedi_check_request_region(dev, start, len, minstart, maxend,
minalign) to perform these additional checks. Turn the original
functions into static inline wrapper functions that call the new
functions.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-2-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
authored by
Ian Abbott
and committed by
Greg Kroah-Hartman
241cb8de
8f348102
+84
-15
+35
-11
drivers/comedi/drivers.c
+35
-11
drivers/comedi/drivers.c
···
933
933
EXPORT_SYMBOL_GPL(comedi_load_firmware);
934
934
935
935
/**
936
-
* __comedi_request_region() - Request an I/O region for a legacy driver
936
+
* __comedi_check_request_region() - Request an I/O region for a legacy driver
937
937
* @dev: COMEDI device.
938
938
* @start: Base address of the I/O region.
939
939
* @len: Length of the I/O region.
940
+
* @minstart: Minimum allowed start address of region.
941
+
* @maxend: Maximum allowed region end address of region.
942
+
* @minalign: Required alignment for base address.
940
943
*
941
944
* Requests the specified I/O port region which must start at a non-zero
942
-
* address.
945
+
* address, must fall within specified bounds, and must be correctly aligned.
943
946
*
944
947
* Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request
945
948
* fails.
946
949
*/
947
-
int __comedi_request_region(struct comedi_device *dev,
948
-
unsigned long start, unsigned long len)
950
+
int __comedi_check_request_region(struct comedi_device *dev,
951
+
unsigned long start, unsigned long len,
952
+
unsigned long minstart, unsigned long maxend,
953
+
unsigned long minalign)
949
954
{
950
955
if (!start) {
951
956
dev_warn(dev->class_dev,
952
957
"%s: a I/O base address must be specified\n",
958
+
dev->board_name);
959
+
return -EINVAL;
960
+
}
961
+
962
+
if (start < minstart || start > maxend || maxend - start < len - 1) {
963
+
dev_warn(dev->class_dev,
964
+
"%s: I/O base address or length out of range\n",
965
+
dev->board_name);
966
+
return -EINVAL;
967
+
}
968
+
if (!IS_ALIGNED(start, minalign)) {
969
+
dev_warn(dev->class_dev,
970
+
"%s: I/O base address not correctly aligned\n",
953
971
dev->board_name);
954
972
return -EINVAL;
955
973
}
···
980
962
981
963
return 0;
982
964
}
983
-
EXPORT_SYMBOL_GPL(__comedi_request_region);
965
+
EXPORT_SYMBOL_GPL(__comedi_check_request_region);
984
966
985
967
/**
986
-
* comedi_request_region() - Request an I/O region for a legacy driver
968
+
* comedi_check_request_region() - Request an I/O region for a legacy driver
987
969
* @dev: COMEDI device.
988
970
* @start: Base address of the I/O region.
989
971
* @len: Length of the I/O region.
972
+
* @minstart: Minimum allowed start address of region.
973
+
* @maxend: Maximum allowed region end address of region.
974
+
* @minalign: Required alignment for base address.
990
975
*
991
976
* Requests the specified I/O port region which must start at a non-zero
992
-
* address.
977
+
* address, must fall within specified bounds, and must be correctly aligned.
993
978
*
994
979
* On success, @dev->iobase is set to the base address of the region and
995
980
* @dev->iolen is set to its length.
···
1000
979
* Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request
1001
980
* fails.
1002
981
*/
1003
-
int comedi_request_region(struct comedi_device *dev,
1004
-
unsigned long start, unsigned long len)
982
+
int comedi_check_request_region(struct comedi_device *dev,
983
+
unsigned long start, unsigned long len,
984
+
unsigned long minstart, unsigned long maxend,
985
+
unsigned long minalign)
1005
986
{
1006
987
int ret;
1007
988
1008
-
ret = __comedi_request_region(dev, start, len);
989
+
ret = __comedi_check_request_region(dev, start, len, minstart, maxend,
990
+
minalign);
1009
991
if (ret == 0) {
1010
992
dev->iobase = start;
1011
993
dev->iolen = len;
···
1016
992
1017
993
return ret;
1018
994
}
1019
-
EXPORT_SYMBOL_GPL(comedi_request_region);
995
+
EXPORT_SYMBOL_GPL(comedi_check_request_region);
1020
996
1021
997
/**
1022
998
* comedi_legacy_detach() - A generic (*detach) function for legacy drivers
+49
-4
include/linux/comedi/comedidev.h
+49
-4
include/linux/comedi/comedidev.h
···
1026
1026
unsigned long context),
1027
1027
unsigned long context);
1028
1028
1029
-
int __comedi_request_region(struct comedi_device *dev,
1030
-
unsigned long start, unsigned long len);
1031
-
int comedi_request_region(struct comedi_device *dev,
1032
-
unsigned long start, unsigned long len);
1029
+
int __comedi_check_request_region(struct comedi_device *dev,
1030
+
unsigned long start, unsigned long len,
1031
+
unsigned long minstart, unsigned long maxend,
1032
+
unsigned long minalign);
1033
+
int comedi_check_request_region(struct comedi_device *dev,
1034
+
unsigned long start, unsigned long len,
1035
+
unsigned long minstart, unsigned long maxend,
1036
+
unsigned long minalign);
1037
+
1038
+
/**
1039
+
* __comedi_request_region() - Request an I/O region for a legacy driver
1040
+
* @dev: COMEDI device.
1041
+
* @start: Base address of the I/O region.
1042
+
* @len: Length of the I/O region.
1043
+
*
1044
+
* Requests the specified I/O port region which must start at a non-zero
1045
+
* address.
1046
+
*
1047
+
* Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request
1048
+
* fails.
1049
+
*/
1050
+
static inline int __comedi_request_region(struct comedi_device *dev,
1051
+
unsigned long start,
1052
+
unsigned long len)
1053
+
{
1054
+
return __comedi_check_request_region(dev, start, len, 0, ~0ul, 1);
1055
+
}
1056
+
1057
+
/**
1058
+
* comedi_request_region() - Request an I/O region for a legacy driver
1059
+
* @dev: COMEDI device.
1060
+
* @start: Base address of the I/O region.
1061
+
* @len: Length of the I/O region.
1062
+
*
1063
+
* Requests the specified I/O port region which must start at a non-zero
1064
+
* address.
1065
+
*
1066
+
* On success, @dev->iobase is set to the base address of the region and
1067
+
* @dev->iolen is set to its length.
1068
+
*
1069
+
* Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request
1070
+
* fails.
1071
+
*/
1072
+
static inline int comedi_request_region(struct comedi_device *dev,
1073
+
unsigned long start, unsigned long len)
1074
+
{
1075
+
return comedi_check_request_region(dev, start, len, 0, ~0ul, 1);
1076
+
}
1077
+
1033
1078
void comedi_legacy_detach(struct comedi_device *dev);
1034
1079
1035
1080
int comedi_auto_config(struct device *hardware_device,