From: Ahmad Fatoum <[email protected]> Drivers using dev_request_mem_resource() have to release the region in every later error path and on remove. Add a managed variant that does this for them.
Assisted-by: Claude:opus-5-1m Signed-off-by: Ahmad Fatoum <[email protected]> --- drivers/base/devres.c | 36 ++++++++++++++++++++++++++++++++++++ include/driver.h | 3 +++ test/self/devres.c | 38 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 77 insertions(+) diff --git a/drivers/base/devres.c b/drivers/base/devres.c index bf118ae0820d..efc810a8898f 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -5,6 +5,7 @@ * Managed resources are children of a per-device talloc context. */ +#include <barebox.h> #include <driver.h> #include <dma.h> #include <talloc.h> @@ -168,3 +169,38 @@ int devm_add_action(struct device *dev, void (*action)(void *), void *data) return talloc_add_destructor(ctx, action, data); } EXPORT_SYMBOL(devm_add_action); + +static void devm_region_release(void *res) +{ + /* No need to release regions when shutting down */ + if (barebox_system_state == BAREBOX_EXITING) + return; + + release_region(res); +} + +/** + * devm_request_mem_resource() - exclusively request resource 'num' for a device + * @dev: device to request the memory resource for + * @num: index of the memory resource + * + * Like dev_request_mem_resource(), but device-managed. + * + * Return: the requested resource or an ERR_PTR() on failure. + */ +struct resource *devm_request_mem_resource(struct device *dev, int num) +{ + struct resource *res; + int ret; + + res = dev_request_mem_resource(dev, num); + if (IS_ERR(res)) + return res; + + ret = devm_add_action_or_reset(dev, devm_region_release, res); + if (ret) + return ERR_PTR(ret); + + return res; +} +EXPORT_SYMBOL(devm_request_mem_resource); diff --git a/include/driver.h b/include/driver.h index c394c455b971..4005804bb1a9 100644 --- a/include/driver.h +++ b/include/driver.h @@ -193,6 +193,9 @@ struct resource *dev_request_mem_resource(struct device *dev, int num); struct resource *dev_request_mem_resource_by_name(struct device *dev, const char *name); +/* Like dev_request_mem_resource(), but released when the device goes away */ +struct resource *devm_request_mem_resource(struct device *dev, int num); + void __iomem *dev_platform_get_and_ioremap_resource(struct device *dev, int num, struct resource **out_res); diff --git a/test/self/devres.c b/test/self/devres.c index 4fdc71064b4a..6992eb20ace3 100644 --- a/test/self/devres.c +++ b/test/self/devres.c @@ -8,6 +8,7 @@ #include <linux/bitmap.h> #include <driver.h> #include <linux/device.h> +#include <linux/sizes.h> BSELFTEST_GLOBALS(); @@ -136,6 +137,42 @@ static void test_devres_shutdown(void) free_device(dev); } +static void test_devres_region(void) +{ + /* The last page of the address space, skipped if it's in use */ + resource_size_t start = iomem_resource.end - SZ_4K + 1; + enum system_states state = barebox_system_state; + struct device *dev = device_alloc("devres-test", DEVICE_ID_DYNAMIC); + struct resource *res; + + device_add_resource(dev, NULL, start, SZ_4K, IORESOURCE_MEM); + if (selftest_check(register_device(dev) == 0) == false) + return; + + res = devm_request_mem_resource(dev, 0); + if (IS_ERR(res)) { + skipped_tests++; + goto out; + } + + /* Shutdown keeps the region, but drops the action all the same */ + barebox_system_state = BAREBOX_EXITING; + devres_run_actions(dev); + barebox_system_state = state; + if (selftest_check(IS_ERR(devm_request_mem_resource(dev, 0)))) + release_region(res); + + /* Releasing frees it */ + selftest_check(!IS_ERR(devm_request_mem_resource(dev, 0))); + devres_release_all(dev); + res = request_iomem_region("devres-test", start, iomem_resource.end); + if (selftest_check(!IS_ERR(res))) + release_region(res); +out: + unregister_device(dev); + free_device(dev); +} + static int probe_result; static char *probe_buf; @@ -282,6 +319,7 @@ static void test_devres(void) test_devres_alloc(); test_devres_action(); test_devres_shutdown(); + test_devres_region(); test_devres_probe(); test_devres_unbind(); test_devres_child(); -- 2.47.3
