From 841f1b8fb4ca5e296e0ecb2b13f2a679d912ec4d Mon Sep 17 00:00:00 2001 From: Mattias Jacobsson Date: Thu, 7 Feb 2019 13:30:22 +0100 Subject: modpost: file2alias: define size of alias The size of the variable alias provided to do_entry functions are currently not readily available. Thus hindering do_entry functions to perform bounds checking. Define the macro ALIAS_SIZE containing the size of the variable alias. Signed-off-by: Mattias Jacobsson <2pi@mok.nu> Acked-by: Masahiro Yamada Signed-off-by: Darren Hart (VMware) --- scripts/mod/file2alias.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index a37af7d71973..afe22af20d7d 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -50,6 +50,9 @@ struct devtable { int (*do_entry)(const char *filename, void *symval, char *alias); }; +/* Size of alias provided to do_entry functions */ +#define ALIAS_SIZE 500 + /* Define a variable f that holds the value of field f of struct devid * based at address m. */ @@ -1303,7 +1306,7 @@ static void do_table(void *symval, unsigned long size, struct module *mod) { unsigned int i; - char alias[500]; + char alias[ALIAS_SIZE]; device_id_check(mod->name, device_id, size, id_size, symval); /* Leave last one: it's the terminator. */ -- cgit v1.2.3 From eacc95eae6837d3f41aed7d30b855a79ab2cb101 Mon Sep 17 00:00:00 2001 From: Mattias Jacobsson Date: Tue, 19 Feb 2019 20:59:49 +0100 Subject: platform/x86: wmi: move struct wmi_device_id to mod_devicetable.h In preparation for adding WMI support to MODULE_DEVICE_TABLE() move the definition of struct wmi_device_id to mod_devicetable.h and inline guid_string in the struct. Changing guid_string to an inline char array changes the loop conditions when looping over an array of struct wmi_device_id. Therefore update wmi_dev_match()'s loop to check for an empty guid_string instead of a NULL pointer. Signed-off-by: Mattias Jacobsson <2pi@mok.nu> [dvhart: Move UUID_STRING_LEN define to this patch] Signed-off-by: Darren Hart (VMware) --- drivers/platform/x86/wmi.c | 2 +- include/linux/mod_devicetable.h | 12 ++++++++++++ include/linux/wmi.h | 5 +---- scripts/mod/file2alias.c | 1 + 4 files changed, 15 insertions(+), 5 deletions(-) (limited to 'scripts') diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index b0f3d8ecd898..7b26b6ccf1a0 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -771,7 +771,7 @@ static int wmi_dev_match(struct device *dev, struct device_driver *driver) if (id == NULL) return 0; - while (id->guid_string) { + while (*id->guid_string) { uuid_le driver_guid; if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid))) diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index f9bd2f34b99f..e44b90fa0aef 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -779,4 +779,16 @@ struct typec_device_id { kernel_ulong_t driver_data; }; +/* WMI */ + +#define WMI_MODULE_PREFIX "wmi:" + +/** + * struct wmi_device_id - WMI device identifier + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + */ +struct wmi_device_id { + const char guid_string[UUID_STRING_LEN+1]; +}; + #endif /* LINUX_MOD_DEVICETABLE_H */ diff --git a/include/linux/wmi.h b/include/linux/wmi.h index 4757cb5077e5..592f81afecbb 100644 --- a/include/linux/wmi.h +++ b/include/linux/wmi.h @@ -18,6 +18,7 @@ #include #include +#include #include struct wmi_device { @@ -39,10 +40,6 @@ extern union acpi_object *wmidev_block_query(struct wmi_device *wdev, extern int set_required_buffer_size(struct wmi_device *wdev, u64 length); -struct wmi_device_id { - const char *guid_string; -}; - struct wmi_driver { struct device_driver driver; const struct wmi_device_id *id_table; diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index afe22af20d7d..4e4f03a12cc0 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -37,6 +37,7 @@ typedef unsigned char __u8; typedef struct { __u8 b[16]; } uuid_le; +#define UUID_STRING_LEN 36 /* Big exception to the "don't include kernel headers into userspace, which * even potentially has different endianness and word sizes, since -- cgit v1.2.3 From 0bc44b2b8ba39212258e2742c2806cdcabad7cba Mon Sep 17 00:00:00 2001 From: Mattias Jacobsson Date: Tue, 19 Feb 2019 20:59:50 +0100 Subject: platform/x86: wmi: add WMI support to MODULE_DEVICE_TABLE() The kernel provides the macro MODULE_DEVICE_TABLE() where driver authors can specify their device type and their array of device_ids and thereby trigger the generation of the appropriate MODULE_ALIAS() output. This is opposed to having to specify one MODULE_ALIAS() for each device. The WMI device type is currently not supported. While using MODULE_DEVICE_TABLE() does increase the complexity as well as spreading out the implementation across the kernel, it does come with some benefits too; * It makes different drivers look more similar; if you can specify the array of device_ids any device type specific input to MODULE_ALIAS() will automatically be generated for you. * It helps each driver avoid keeping multiple versions of the same information in sync. That is, both the array of device_ids and the potential multitude of MODULE_ALIAS()'s. Add WMI support to MODULE_DEVICE_TABLE() by adding info about struct wmi_device_id in devicetable-offsets.c and add a WMI entry point in file2alias.c. The type argument for MODULE_DEVICE_TABLE(type, name) is wmi. Suggested-by: Pali Rohár Signed-off-by: Mattias Jacobsson <2pi@mok.nu> Acked-by: Masahiro Yamada Signed-off-by: Darren Hart (VMware) --- scripts/mod/devicetable-offsets.c | 3 +++ scripts/mod/file2alias.c | 22 ++++++++++++++++++++++ 2 files changed, 25 insertions(+) (limited to 'scripts') diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c index 293004499b4d..99276a422e77 100644 --- a/scripts/mod/devicetable-offsets.c +++ b/scripts/mod/devicetable-offsets.c @@ -225,5 +225,8 @@ int main(void) DEVID_FIELD(typec_device_id, svid); DEVID_FIELD(typec_device_id, mode); + DEVID(wmi_device_id); + DEVID_FIELD(wmi_device_id, guid_string); + return 0; } diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 4e4f03a12cc0..6dedc31a4925 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1291,6 +1291,27 @@ static int do_typec_entry(const char *filename, void *symval, char *alias) return 1; } +/* Looks like: wmi:guid */ +static int do_wmi_entry(const char *filename, void *symval, char *alias) +{ + int len; + DEF_FIELD_ADDR(symval, wmi_device_id, guid_string); + + if (strlen(*guid_string) != UUID_STRING_LEN) { + warn("Invalid WMI device id 'wmi:%s' in '%s'\n", + *guid_string, filename); + return 0; + } + + len = snprintf(alias, ALIAS_SIZE, WMI_MODULE_PREFIX "%s", *guid_string); + if (len < 0 || len >= ALIAS_SIZE) { + warn("Could not generate all MODULE_ALIAS's in '%s'\n", + filename); + return 0; + } + return 1; +} + /* Does namelen bytes of name exactly match the symbol? */ static bool sym_is(const char *name, unsigned namelen, const char *symbol) { @@ -1361,6 +1382,7 @@ static const struct devtable devtable[] = { {"fslmc", SIZE_fsl_mc_device_id, do_fsl_mc_entry}, {"tbsvc", SIZE_tb_service_id, do_tbsvc_entry}, {"typec", SIZE_typec_device_id, do_typec_entry}, + {"wmi", SIZE_wmi_device_id, do_wmi_entry}, }; /* Create MODULE_ALIAS() statements. -- cgit v1.2.3