| Message ID | 1309539333-2606-12-git-send-email-per.forlin@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
This patch prevents mmc core to be built as a module if mmc fault injection is selected. Changes needed to resolve this: * remove fault inject module from core.c * export should_fail() and init_fault_attr_dentries() in fault-injection.c * update documentation fault-injection.txt On 1 July 2011 18:55, Per Forlin <per.forlin@linaro.org> wrote: > This simple fault injection proved to be very useful to > test the error handling in the block.c rw_rq(). It may > still be useful to test if the host driver handle > pre_req() and post_req() correctly in case of errors. > > Signed-off-by: Per Forlin <per.forlin@linaro.org> > Acked-by: Kyungmin Park <kyungmin.park@samsung.com> > Acked-by: Arnd Bergmann <arnd@arndb.de> > Reviewed-by: Venkatraman S <svenkatr@ti.com> > Tested-by: Sourav Poddar<sourav.poddar@ti.com> > Tested-by: Linus Walleij <linus.walleij@linaro.org> > --- > drivers/mmc/core/core.c | 54 ++++++++++++++++++++++++++++++++++++++++++++ > drivers/mmc/core/debugfs.c | 5 ++++ > include/linux/mmc/host.h | 3 ++ > lib/Kconfig.debug | 11 +++++++++ > 4 files changed, 73 insertions(+), 0 deletions(-) > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index d2d7239..62a8cc7 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -23,6 +23,8 @@ > #include <linux/log2.h> > #include <linux/regulator/consumer.h> > #include <linux/pm_runtime.h> > +#include <linux/fault-inject.h> > +#include <linux/random.h> > > #include <linux/mmc/card.h> > #include <linux/mmc/host.h> > @@ -82,6 +84,56 @@ static void mmc_flush_scheduled_work(void) > flush_workqueue(workqueue); > } > > +#ifdef CONFIG_FAIL_MMC_REQUEST > + > +static DECLARE_FAULT_ATTR(fail_mmc_request); > + > +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); > + > +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 || !host->make_it_fail || > + !should_fail(&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; > +} > + > +static int __init fail_mmc_request_debugfs(void) > +{ > + return init_fault_attr_dentries(&fail_mmc_request, > + "fail_mmc_request"); > +} > + > +late_initcall(fail_mmc_request_debugfs); This line prevents mmc core to be built as a module, since there will be two init_module (the mmc core one and this one) for the same module. > + > +#else /* CONFIG_FAIL_MMC_REQUEST */ > + > +static void mmc_should_fail_request(struct mmc_host *host, > + struct mmc_request *mrq) > +{ > +} > + +static int __init fail_mmc_request_debugfs(void) +{ +} Add fail_mmc_request_debugfs here and call it from mmc_init() > +#endif /* CONFIG_FAIL_MMC_REQUEST */ > + > + > /** > * mmc_request_done - finish processing an MMC request > * @host: MMC host which completed request > @@ -108,6 +160,8 @@ 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 998797e..588e76f 100644 > --- a/drivers/mmc/core/debugfs.c > +++ b/drivers/mmc/core/debugfs.c > @@ -188,6 +188,11 @@ void mmc_add_host_debugfs(struct mmc_host *host) > root, &host->clk_delay)) > goto err_node; > #endif > +#ifdef CONFIG_FAIL_MMC_REQUEST > + if (!debugfs_create_u8("make-it-fail", S_IRUSR | S_IWUSR, > + root, &host->make_it_fail)) > + goto err_node; > +#endif > return; > > err_node: > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index 59db6f2..0d0a48f 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -301,6 +301,9 @@ struct mmc_host { > > struct mmc_async_req *areq; /* active async req */ > > +#ifdef CONFIG_FAIL_MMC_REQUEST > + u8 make_it_fail; > +#endif > unsigned long private[0] ____cacheline_aligned; > }; > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index c768bcd..330fc70 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1057,6 +1057,17 @@ 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 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 for testing the error handling in the mmc block device > + and how the mmc host driver handle retries from > + the block device. and test how the mmc host driver handle retries from
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index d2d7239..62a8cc7 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -23,6 +23,8 @@ #include <linux/log2.h> #include <linux/regulator/consumer.h> #include <linux/pm_runtime.h> +#include <linux/fault-inject.h> +#include <linux/random.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> @@ -82,6 +84,56 @@ static void mmc_flush_scheduled_work(void) flush_workqueue(workqueue); } +#ifdef CONFIG_FAIL_MMC_REQUEST + +static DECLARE_FAULT_ATTR(fail_mmc_request); + +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); + +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 || !host->make_it_fail || + !should_fail(&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; +} + +static int __init fail_mmc_request_debugfs(void) +{ + return init_fault_attr_dentries(&fail_mmc_request, + "fail_mmc_request"); +} + +late_initcall(fail_mmc_request_debugfs); + +#else /* CONFIG_FAIL_MMC_REQUEST */ + +static 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 @@ -108,6 +160,8 @@ 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 998797e..588e76f 100644 --- a/drivers/mmc/core/debugfs.c +++ b/drivers/mmc/core/debugfs.c @@ -188,6 +188,11 @@ void mmc_add_host_debugfs(struct mmc_host *host) root, &host->clk_delay)) goto err_node; #endif +#ifdef CONFIG_FAIL_MMC_REQUEST + if (!debugfs_create_u8("make-it-fail", S_IRUSR | S_IWUSR, + root, &host->make_it_fail)) + goto err_node; +#endif return; err_node: diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 59db6f2..0d0a48f 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -301,6 +301,9 @@ struct mmc_host { struct mmc_async_req *areq; /* active async req */ +#ifdef CONFIG_FAIL_MMC_REQUEST + u8 make_it_fail; +#endif unsigned long private[0] ____cacheline_aligned; }; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index c768bcd..330fc70 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1057,6 +1057,17 @@ 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 + help + Provide fault-injection capability for MMC IO. + This will make the mmc core return data errors. This is + useful for testing the error handling in the mmc block device + and how the mmc host driver handle retries from + the block device. + config FAULT_INJECTION_DEBUG_FS bool "Debugfs entries for fault-injection capabilities" depends on FAULT_INJECTION && SYSFS && DEBUG_FS