Message ID | 4C7F7A1B.5040800@canonical.com |
---|---|
State | Rejected |
Delegated to: | Leann Ogasawara |
Headers | show |
On Thu, Sep 02, 2010 at 11:19:07AM +0100, Lee Jones wrote: > This patch fixes: > > BugLink: http://bugs.launchpad.net/bugs/477106 > > The following changes since commit 9f02aef9921f0f213a6680768641eb2af6113c3b: > Leann Ogasawara (1): > UBUNTU: Start new release > > are available in the git repository at: > > git://kernel.ubuntu.com/lag/ubuntu-maverick.git lp477106-mmc-suspend > > Maxim Levitsky (1): > mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume > > drivers/mmc/core/core.c | 83 +++++++++++++++++++++++++++++++-------------- > drivers/mmc/core/host.c | 4 ++ > include/linux/mmc/host.h | 3 ++ > 3 files changed, 64 insertions(+), 26 deletions(-) > > ------------------------------------------------------------------- > > From: Maxim Levitsky <maximlevitsky@gmail.com> > Date: Wed, 11 Aug 2010 01:01:41 +0000 (-0700) > Subject: mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume > > mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume > > If you don't use CONFIG_MMC_UNSAFE_RESUME, as soon as you attempt to > suspend, the card will be removed, therefore this patch doesn't change the > behavior of this option. > > However the removal will be done by pm notifier, which runs while > userspace is still not frozen and thus can freely use del_gendisk, without > the risk of deadlock which would happen otherwise. > > Card detect workqueue is now disabled while userspace is frozen, Therefore > if you do use CONFIG_MMC_UNSAFE_RESUME, and remove the card during > suspend, the removal will be detected as soon as userspace is unfrozen, > again at the moment it is safe to call del_gendisk. > > Tested with and without CONFIG_MMC_UNSAFE_RESUME with suspend and hibernate. > > Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> > Signed-off-by: Andrew Morton <akpm@linux-foundation.org> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> From the signed-off-by lines I assume this is an upstream patch from Linus' tree. If so you should use the -x option when cherry picking it so we retain the upstream identifier. This is critical when we carry forward the patch set to Natty. -apw > --- > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index b69ce91..83240fa 100644 > --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -1057,6 +1057,17 @@ void mmc_rescan(struct work_struct *work) > container_of(work, struct mmc_host, detect.work); > u32 ocr; > int err; > + unsigned long flags; > + > + spin_lock_irqsave(&host->lock, flags); > + > + if (host->rescan_disable) { > + spin_unlock_irqrestore(&host->lock, flags); > + return; > + } > + > + spin_unlock_irqrestore(&host->lock, flags); > + > > mmc_bus_get(host); > > @@ -1274,19 +1285,6 @@ int mmc_suspend_host(struct mmc_host *host) > if (host->bus_ops && !host->bus_dead) { > if (host->bus_ops->suspend) > err = host->bus_ops->suspend(host); > - if (err == -ENOSYS || !host->bus_ops->resume) { > - /* > - * We simply "remove" the card in this case. > - * It will be redetected on resume. > - */ > - if (host->bus_ops->remove) > - host->bus_ops->remove(host); > - mmc_claim_host(host); > - mmc_detach_bus(host); > - mmc_release_host(host); > - host->pm_flags = 0; > - err = 0; > - } > } > mmc_bus_put(host); > > @@ -1318,28 +1316,61 @@ int mmc_resume_host(struct mmc_host *host) > printk(KERN_WARNING "%s: error %d during resume " > "(card was removed?)\n", > mmc_hostname(host), err); > - if (host->bus_ops->remove) > - host->bus_ops->remove(host); > - mmc_claim_host(host); > - mmc_detach_bus(host); > - mmc_release_host(host); > - /* no need to bother upper layers */ > err = 0; > } > } > mmc_bus_put(host); > > - /* > - * We add a slight delay here so that resume can progress > - * in parallel. > - */ > - mmc_detect_change(host, 1); > - > return err; > } > - > EXPORT_SYMBOL(mmc_resume_host); > > +/* Do the card removal on suspend if card is assumed removeable > + * Do that in pm notifier while userspace isn't yet frozen, so we will be able > + to sync the card. > +*/ > +int mmc_pm_notify(struct notifier_block *notify_block, > + unsigned long mode, void *unused) > +{ > + struct mmc_host *host = container_of( > + notify_block, struct mmc_host, pm_notify); > + unsigned long flags; > + > + > + switch (mode) { > + case PM_HIBERNATION_PREPARE: > + case PM_SUSPEND_PREPARE: > + > + spin_lock_irqsave(&host->lock, flags); > + host->rescan_disable = 1; > + spin_unlock_irqrestore(&host->lock, flags); > + cancel_delayed_work_sync(&host->detect); > + > + if (!host->bus_ops || host->bus_ops->suspend) > + break; > + > + mmc_claim_host(host); > + > + if (host->bus_ops->remove) > + host->bus_ops->remove(host); > + > + mmc_detach_bus(host); > + mmc_release_host(host); > + host->pm_flags = 0; > + break; > + > + case PM_POST_SUSPEND: > + case PM_POST_HIBERNATION: > + > + spin_lock_irqsave(&host->lock, flags); > + host->rescan_disable = 0; > + spin_unlock_irqrestore(&host->lock, flags); > + mmc_detect_change(host, 0); > + > + } > + > + return 0; > +} > #endif > > static int __init mmc_init(void) > diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c > index 4735390..0efe631 100644 > --- a/drivers/mmc/core/host.c > +++ b/drivers/mmc/core/host.c > @@ -17,6 +17,7 @@ > #include <linux/pagemap.h> > #include <linux/leds.h> > #include <linux/slab.h> > +#include <linux/suspend.h> > > #include <linux/mmc/host.h> > > @@ -85,6 +86,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) > init_waitqueue_head(&host->wq); > INIT_DELAYED_WORK(&host->detect, mmc_rescan); > INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable); > + host->pm_notify.notifier_call = mmc_pm_notify; > > /* > * By default, hosts do not support SGIO or large requests. > @@ -133,6 +135,7 @@ int mmc_add_host(struct mmc_host *host) > #endif > > mmc_start_host(host); > + register_pm_notifier(&host->pm_notify); > > return 0; > } > @@ -149,6 +152,7 @@ EXPORT_SYMBOL(mmc_add_host); > */ > void mmc_remove_host(struct mmc_host *host) > { > + unregister_pm_notifier(&host->pm_notify); > mmc_stop_host(host); > > #ifdef CONFIG_DEBUG_FS > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index f65913c..513ff03 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -124,6 +124,7 @@ struct mmc_host { > unsigned int f_min; > unsigned int f_max; > u32 ocr_avail; > + struct notifier_block pm_notify; > > #define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - 1.95 */ > #define MMC_VDD_20_21 0x00000100 /* VDD voltage 2.0 ~ 2.1 */ > @@ -183,6 +184,7 @@ struct mmc_host { > > /* Only used with MMC_CAP_DISABLE */ > int enabled; /* host is enabled */ > + int rescan_disable; /* disable card detection */ > int nesting_cnt; /* "enable" nesting count */ > int en_dis_recurs; /* detect recursion */ > unsigned int disable_delay; /* disable delay in msecs */ > @@ -257,6 +259,7 @@ int mmc_card_can_sleep(struct mmc_host *host); > int mmc_host_enable(struct mmc_host *host); > int mmc_host_disable(struct mmc_host *host); > int mmc_host_lazy_disable(struct mmc_host *host); > +int mmc_pm_notify(struct notifier_block *notify_block, unsigned long, void *); > > static inline void mmc_set_disable_delay(struct mmc_host *host, > unsigned int disable_delay) > > -- > kernel-team mailing list > kernel-team@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/kernel-team
>> Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> >> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> >> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> > > From the signed-off-by lines I assume this is an upstream patch from > Linus' tree. If so you should use the -x option when cherry picking it > so we retain the upstream identifier. This is critical when we carry > forward the patch set to Natty. Sounds reasonable. I'll cherry pick it again with the -x option.
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index b69ce91..83240fa 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1057,6 +1057,17 @@ void mmc_rescan(struct work_struct *work) container_of(work, struct mmc_host, detect.work); u32 ocr; int err; + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + + if (host->rescan_disable) { + spin_unlock_irqrestore(&host->lock, flags); + return; + } + + spin_unlock_irqrestore(&host->lock, flags); + mmc_bus_get(host); @@ -1274,19 +1285,6 @@ int mmc_suspend_host(struct mmc_host *host) if (host->bus_ops && !host->bus_dead) { if (host->bus_ops->suspend) err = host->bus_ops->suspend(host); - if (err == -ENOSYS || !host->bus_ops->resume) { - /* - * We simply "remove" the card in this case. - * It will be redetected on resume. - */ - if (host->bus_ops->remove) - host->bus_ops->remove(host); - mmc_claim_host(host); - mmc_detach_bus(host); - mmc_release_host(host); - host->pm_flags = 0; - err = 0; - } } mmc_bus_put(host); @@ -1318,28 +1316,61 @@ int mmc_resume_host(struct mmc_host *host) printk(KERN_WARNING "%s: error %d during resume " "(card was removed?)\n", mmc_hostname(host), err); - if (host->bus_ops->remove) - host->bus_ops->remove(host); - mmc_claim_host(host); - mmc_detach_bus(host); - mmc_release_host(host); - /* no need to bother upper layers */ err = 0; } } mmc_bus_put(host); - /* - * We add a slight delay here so that resume can progress - * in parallel. - */ - mmc_detect_change(host, 1); - return err; } - EXPORT_SYMBOL(mmc_resume_host); +/* Do the card removal on suspend if card is assumed removeable + * Do that in pm notifier while userspace isn't yet frozen, so we will be able + to sync the card. +*/ +int mmc_pm_notify(struct notifier_block *notify_block, + unsigned long mode, void *unused) +{ + struct mmc_host *host = container_of( + notify_block, struct mmc_host, pm_notify); + unsigned long flags; + + + switch (mode) { + case PM_HIBERNATION_PREPARE: + case PM_SUSPEND_PREPARE: + + spin_lock_irqsave(&host->lock, flags); + host->rescan_disable = 1; + spin_unlock_irqrestore(&host->lock, flags); + cancel_delayed_work_sync(&host->detect); + + if (!host->bus_ops || host->bus_ops->suspend) + break; + + mmc_claim_host(host); + + if (host->bus_ops->remove) + host->bus_ops->remove(host); + + mmc_detach_bus(host); + mmc_release_host(host); + host->pm_flags = 0; + break; + + case PM_POST_SUSPEND: + case PM_POST_HIBERNATION: + + spin_lock_irqsave(&host->lock, flags); + host->rescan_disable = 0; + spin_unlock_irqrestore(&host->lock, flags); + mmc_detect_change(host, 0); + + } + + return 0; +} #endif static int __init mmc_init(void) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 4735390..0efe631 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -17,6 +17,7 @@ #include <linux/pagemap.h> #include <linux/leds.h> #include <linux/slab.h> +#include <linux/suspend.h> #include <linux/mmc/host.h> @@ -85,6 +86,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) init_waitqueue_head(&host->wq); INIT_DELAYED_WORK(&host->detect, mmc_rescan); INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable); + host->pm_notify.notifier_call = mmc_pm_notify; /* * By default, hosts do not support SGIO or large requests. @@ -133,6 +135,7 @@ int mmc_add_host(struct mmc_host *host) #endif mmc_start_host(host); + register_pm_notifier(&host->pm_notify); return 0; } @@ -149,6 +152,7 @@ EXPORT_SYMBOL(mmc_add_host); */ void mmc_remove_host(struct mmc_host *host) { + unregister_pm_notifier(&host->pm_notify); mmc_stop_host(host); #ifdef CONFIG_DEBUG_FS diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index f65913c..513ff03 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -124,6 +124,7 @@ struct mmc_host { unsigned int f_min; unsigned int f_max; u32 ocr_avail; + struct notifier_block pm_notify; #define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - 1.95 */ #define MMC_VDD_20_21 0x00000100 /* VDD voltage 2.0 ~ 2.1 */ @@ -183,6 +184,7 @@ struct mmc_host { /* Only used with MMC_CAP_DISABLE */ int enabled; /* host is enabled */ + int rescan_disable; /* disable card detection */ int nesting_cnt; /* "enable" nesting count */ int en_dis_recurs; /* detect recursion */ unsigned int disable_delay; /* disable delay in msecs */ @@ -257,6 +259,7 @@ int mmc_card_can_sleep(struct mmc_host *host); int mmc_host_enable(struct mmc_host *host); int mmc_host_disable(struct mmc_host *host); int mmc_host_lazy_disable(struct mmc_host *host); +int mmc_pm_notify(struct notifier_block *notify_block, unsigned long, void *); static inline void mmc_set_disable_delay(struct mmc_host *host, unsigned int disable_delay)