driver core: Add "*" wildcard support to driver_async_probe cmdline param
There's currently no way to use driver_async_probe kernel cmdline param
to enable default async probe for all drivers. So, add support for "*"
to match with all driver names. When "*" is used, all other drivers
listed in driver_async_probe are drivers that will NOT match the "*".
For example:
* driver_async_probe=drvA,drvB,drvC
drvA, drvB and drvC do asynchronous probing.
* driver_async_probe=*
All drivers do asynchronous probing except those that have set
PROBE_FORCE_SYNCHRONOUS flag.
* driver_async_probe=*,drvA,drvB,drvC
All drivers do asynchronous probing except drvA, drvB, drvC and those
that have set PROBE_FORCE_SYNCHRONOUS flag.
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Feng Tang <feng.tang@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20220504005344.117803-1-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 39c70fc..810f45c 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -60,6 +60,7 @@ static bool initcalls_done;
/* Save the async probe drivers' name from kernel cmdline */
#define ASYNC_DRV_NAMES_MAX_LEN 256
static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN];
+static bool async_probe_default;
/*
* In some cases, like suspend to RAM or hibernation, It might be reasonable
@@ -797,7 +798,11 @@ static int driver_probe_device(struct device_driver *drv, struct device *dev)
static inline bool cmdline_requested_async_probing(const char *drv_name)
{
- return parse_option_str(async_probe_drv_names, drv_name);
+ bool async_drv;
+
+ async_drv = parse_option_str(async_probe_drv_names, drv_name);
+
+ return (async_probe_default != async_drv);
}
/* The option format is "driver_async_probe=drv_name1,drv_name2,..." */
@@ -807,6 +812,8 @@ static int __init save_async_options(char *buf)
pr_warn("Too long list of driver names for 'driver_async_probe'!\n");
strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN);
+ async_probe_default = parse_option_str(async_probe_drv_names, "*");
+
return 1;
}
__setup("driver_async_probe=", save_async_options);
