diff options
| -rw-r--r-- | drivers/mmc/core/core.c | 41 | ||||
| -rw-r--r-- | drivers/mmc/core/debugfs.c | 25 | ||||
| -rw-r--r-- | include/linux/mmc/host.h | 5 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 11 |
4 files changed, 82 insertions, 0 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index b27b94078c21..eb3069dfea8e 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -24,6 +24,8 @@ #include <linux/regulator/consumer.h> #include <linux/pm_runtime.h> #include <linux/suspend.h> +#include <linux/fault-inject.h> +#include <linux/random.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> @@ -83,6 +85,43 @@ static void mmc_flush_scheduled_work(void) flush_workqueue(workqueue); } +#ifdef CONFIG_FAIL_MMC_REQUEST + +/* + * Internal function. Inject random data errors. + * If mmc_data is NULL no errors are injected. + */ +static void mmc_should_fail_request(struct mmc_host *host, + struct mmc_request *mrq) +{ + struct mmc_command *cmd = mrq->cmd; + struct mmc_data *data = mrq->data; + static const int data_errors[] = { + -ETIMEDOUT, + -EILSEQ, + -EIO, + }; + + if (!data) + return; + + if (cmd->error || data->error || + !should_fail(&host->fail_mmc_request, data->blksz * data->blocks)) + return; + + data->error = data_errors[random32() % ARRAY_SIZE(data_errors)]; + data->bytes_xfered = (random32() % (data->bytes_xfered >> 9)) << 9; +} + +#else /* CONFIG_FAIL_MMC_REQUEST */ + +static inline void mmc_should_fail_request(struct mmc_host *host, + struct mmc_request *mrq) +{ +} + +#endif /* CONFIG_FAIL_MMC_REQUEST */ + /** * mmc_request_done - finish processing an MMC request * @host: MMC host which completed request @@ -109,6 +148,8 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq) cmd->error = 0; host->ops->request(host, mrq); } else { + mmc_should_fail_request(host, mrq); + led_trigger_event(host->led, LED_OFF); pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n", diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c index 998797ed67a6..5acd707699c9 100644 --- a/drivers/mmc/core/debugfs.c +++ b/drivers/mmc/core/debugfs.c @@ -12,6 +12,7 @@ #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/stat.h> +#include <linux/fault-inject.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> @@ -158,6 +159,23 @@ static int mmc_clock_opt_set(void *data, u64 val) return 0; } +#ifdef CONFIG_FAIL_MMC_REQUEST + +static DECLARE_FAULT_ATTR(fail_mmc_request); + +#ifdef KERNEL +/* + * Internal function. Pass the boot param fail_mmc_request to + * the setup fault injection attributes routine. + */ +static int __init setup_fail_mmc_request(char *str) +{ + return setup_fault_attr(&fail_mmc_request, str); +} +__setup("fail_mmc_request=", setup_fail_mmc_request); +#endif /* KERNEL */ +#endif /* CONFIG_FAIL_MMC_REQUEST */ + DEFINE_SIMPLE_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, mmc_clock_opt_set, "%llu\n"); @@ -188,6 +206,13 @@ void mmc_add_host_debugfs(struct mmc_host *host) root, &host->clk_delay)) goto err_node; #endif +#ifdef CONFIG_FAIL_MMC_REQUEST + host->fail_mmc_request = fail_mmc_request; + if (IS_ERR(fault_create_debugfs_attr("fail_mmc_request", + root, + &host->fail_mmc_request))) + goto err_node; +#endif return; err_node: diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 1d09562ccf73..4c4bddf5ef61 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -12,6 +12,7 @@ #include <linux/leds.h> #include <linux/sched.h> +#include <linux/fault-inject.h> #include <linux/mmc/core.h> #include <linux/mmc/pm.h> @@ -302,6 +303,10 @@ struct mmc_host { struct mmc_async_req *areq; /* active async req */ +#ifdef CONFIG_FAIL_MMC_REQUEST + struct fault_attr fail_mmc_request; +#endif + unsigned long private[0] ____cacheline_aligned; }; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index c0cb9c4bc46d..1c7dbbf9e449 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1070,6 +1070,17 @@ config FAIL_IO_TIMEOUT Only works with drivers that use the generic timeout handling, for others it wont do anything. +config FAIL_MMC_REQUEST + bool "Fault-injection capability for MMC IO" + select DEBUG_FS + depends on FAULT_INJECTION && MMC + help + Provide fault-injection capability for MMC IO. + This will make the mmc core return data errors. This is + useful to test the error handling in the mmc block device + and to test how the mmc host driver handles retries from + the block device. + config FAULT_INJECTION_DEBUG_FS bool "Debugfs entries for fault-injection capabilities" depends on FAULT_INJECTION && SYSFS && DEBUG_FS |