| Message ID | 0d0ef6651ed44fc780e95c8797294708@hyperstone.com |
|---|---|
| State | New |
| Headers | show |
| Series | [PATCHv3,1/2] mmc: block: Remove error check of hw_reset on reset | expand |
On 10/10/22 17:03, Christian Löhle wrote: > Before switching back to the right partition in mmc_blk_reset > there used to be a check if hw_reset was even supported. > This return value was removed, so there is no reason to check. > Furthermore ensure part_curr is not falsely set to a valid value > on reset or partition switch error. > > Fixes: fefdd3c91e0a ("mmc: core: Drop superfluous validations in mmc_hw|sw_reset()") > Cc: stable@vger.kernel.org > > Signed-off-by: Christian Loehle <cloehle@hyperstone.com> > --- > -v3: Ensure invalid part_curr on error > -v2: Do not attempt to switch partitions if reset failed > > drivers/mmc/core/block.c | 29 ++++++++++++++--------------- > 1 file changed, 14 insertions(+), 15 deletions(-) > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > index ce89611a136e..45a44edcc31a 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -134,6 +134,7 @@ struct mmc_blk_data { > * track of the current selected device partition. > */ > unsigned int part_curr; > +#define MMC_BLK_PART_INVALID UINT_MAX /* Unknown partition active */ > int area_type; > > /* debugfs files (only in main mmc_blk_data) */ > @@ -991,29 +992,27 @@ static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host, > int type) > { > int err; > + struct mmc_blk_data *main_md = dev_get_drvdata(&host->card->dev); > + int part_err; > > if (md->reset_done & type) > return -EEXIST; > > md->reset_done |= type; > + main_md->part_curr = MMC_BLK_PART_INVALID; This forces a partition switch even if it is not necessary. > err = mmc_hw_reset(host->card); This would be better: /* * A successful reset will leave the card in the main partition, but * upon failure it might not be, so set it to MMC_BLK_PART_INVALID * in that case. */ main_md->part_curr = err ? MMC_BLK_PART_INVALID : main_md->part_type; > + if (err) > + return err; There was a time when mmc requests would be retried directly without going back through the block layer. I don't think that can happen anymore after a failed reset. However, if you are going to skip the partition switch, the commit message needs to explain that you have checked the code paths and we never retry a request directly after a failed reset. Also a comment is needed to say the same. > /* Ensure we switch back to the correct partition */ > - if (err) { > - struct mmc_blk_data *main_md = > - dev_get_drvdata(&host->card->dev); > - int part_err; > - > - main_md->part_curr = main_md->part_type; > - part_err = mmc_blk_part_switch(host->card, md->part_type); > - if (part_err) { > - /* > - * We have failed to get back into the correct > - * partition, so we need to abort the whole request. > - */ > - return -ENODEV; > - } > + part_err = mmc_blk_part_switch(host->card, md->part_type); > + if (part_err) { Don't really need part_err. i.e. could be if (mmc_blk_part_switch(host->card, md->part_type) { > + /* > + * We have failed to get back into the correct > + * partition, so we need to abort the whole request. > + */ > + return -ENODEV; > } > - return err; > + return 0; > } > > static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
On Tue, 11 Oct 2022 at 12:15, Adrian Hunter <adrian.hunter@intel.com> wrote: > > On 10/10/22 17:03, Christian Löhle wrote: > > Before switching back to the right partition in mmc_blk_reset > > there used to be a check if hw_reset was even supported. > > This return value was removed, so there is no reason to check. > > Furthermore ensure part_curr is not falsely set to a valid value > > on reset or partition switch error. > > > > Fixes: fefdd3c91e0a ("mmc: core: Drop superfluous validations in mmc_hw|sw_reset()") > > Cc: stable@vger.kernel.org > > > > Signed-off-by: Christian Loehle <cloehle@hyperstone.com> > > --- > > -v3: Ensure invalid part_curr on error > > -v2: Do not attempt to switch partitions if reset failed > > > > drivers/mmc/core/block.c | 29 ++++++++++++++--------------- > > 1 file changed, 14 insertions(+), 15 deletions(-) > > > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > > index ce89611a136e..45a44edcc31a 100644 > > --- a/drivers/mmc/core/block.c > > +++ b/drivers/mmc/core/block.c > > @@ -134,6 +134,7 @@ struct mmc_blk_data { > > * track of the current selected device partition. > > */ > > unsigned int part_curr; > > +#define MMC_BLK_PART_INVALID UINT_MAX /* Unknown partition active */ > > int area_type; > > > > /* debugfs files (only in main mmc_blk_data) */ > > @@ -991,29 +992,27 @@ static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host, > > int type) > > { > > int err; > > + struct mmc_blk_data *main_md = dev_get_drvdata(&host->card->dev); > > + int part_err; > > > > if (md->reset_done & type) > > return -EEXIST; > > > > md->reset_done |= type; > > + main_md->part_curr = MMC_BLK_PART_INVALID; > > This forces a partition switch even if it is not necessary. Right, very good point! > > > err = mmc_hw_reset(host->card); > > This would be better: > > /* > * A successful reset will leave the card in the main partition, but > * upon failure it might not be, so set it to MMC_BLK_PART_INVALID > * in that case. > */ > main_md->part_curr = err ? MMC_BLK_PART_INVALID : main_md->part_type; > Yes! And the comment is valuable too! [...] Kind regards Uffe
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index ce89611a136e..45a44edcc31a 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -134,6 +134,7 @@ struct mmc_blk_data { * track of the current selected device partition. */ unsigned int part_curr; +#define MMC_BLK_PART_INVALID UINT_MAX /* Unknown partition active */ int area_type; /* debugfs files (only in main mmc_blk_data) */ @@ -991,29 +992,27 @@ static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host, int type) { int err; + struct mmc_blk_data *main_md = dev_get_drvdata(&host->card->dev); + int part_err; if (md->reset_done & type) return -EEXIST; md->reset_done |= type; + main_md->part_curr = MMC_BLK_PART_INVALID; err = mmc_hw_reset(host->card); + if (err) + return err; /* Ensure we switch back to the correct partition */ - if (err) { - struct mmc_blk_data *main_md = - dev_get_drvdata(&host->card->dev); - int part_err; - - main_md->part_curr = main_md->part_type; - part_err = mmc_blk_part_switch(host->card, md->part_type); - if (part_err) { - /* - * We have failed to get back into the correct - * partition, so we need to abort the whole request. - */ - return -ENODEV; - } + part_err = mmc_blk_part_switch(host->card, md->part_type); + if (part_err) { + /* + * We have failed to get back into the correct + * partition, so we need to abort the whole request. + */ + return -ENODEV; } - return err; + return 0; } static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
Before switching back to the right partition in mmc_blk_reset there used to be a check if hw_reset was even supported. This return value was removed, so there is no reason to check. Furthermore ensure part_curr is not falsely set to a valid value on reset or partition switch error. Fixes: fefdd3c91e0a ("mmc: core: Drop superfluous validations in mmc_hw|sw_reset()") Cc: stable@vger.kernel.org Signed-off-by: Christian Loehle <cloehle@hyperstone.com> --- -v3: Ensure invalid part_curr on error -v2: Do not attempt to switch partitions if reset failed drivers/mmc/core/block.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-)