This is a note to let you know that I've just added the patch titled scsi: libsas: Introduce a _gfp() variant of event notifiers to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-libsas-introduce-a-_gfp-variant-of-event-notifi.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit eb45ea36be730c7f29f8aaf1b19bec62c0277fcf Author: Ahmed S. Darwish <a.darwish@xxxxxxxxxxxxx> Date: Mon Jan 18 11:09:39 2021 +0100 scsi: libsas: Introduce a _gfp() variant of event notifiers [ Upstream commit c2d0f1a65ab9fbabebb463bf36f50ea8f4633386 ] sas_alloc_event() uses in_interrupt() to decide which allocation should be used. The usage of in_interrupt() in drivers is phased out and Linus clearly requested that code which changes behaviour depending on context should either be separated or the context be conveyed in an argument passed by the caller, which usually knows the context. The in_interrupt() check is also only partially correct, because it fails to choose the correct code path when just preemption or interrupts are disabled. For example, as in the following call chain: mvsas/mv_sas.c: mvs_work_queue() [process context] spin_lock_irqsave(mvs_info::lock, ) -> libsas/sas_event.c: sas_notify_phy_event() -> sas_alloc_event() -> in_interrupt() = false -> invalid GFP_KERNEL allocation -> libsas/sas_event.c: sas_notify_port_event() -> sas_alloc_event() -> in_interrupt() = false -> invalid GFP_KERNEL allocation Introduce sas_alloc_event_gfp(), sas_notify_port_event_gfp(), and sas_notify_phy_event_gfp(), which all behave like the non _gfp() variants but use a caller-passed GFP mask for allocations. For bisectability, all callers will be modified first to pass GFP context, then the non _gfp() libsas API variants will be modified to take a gfp_t by default. Link: https://lore.kernel.org/r/20210118100955.1761652-4-a.darwish@xxxxxxxxxxxxx Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost") Cc: Jason Yan <yanaijie@xxxxxxxxxx> Reviewed-by: John Garry <john.garry@xxxxxxxxxx> Signed-off-by: Ahmed S. Darwish <a.darwish@xxxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/Documentation/scsi/libsas.rst b/Documentation/scsi/libsas.rst index 210df1aba1409..de422253b0ab7 100644 --- a/Documentation/scsi/libsas.rst +++ b/Documentation/scsi/libsas.rst @@ -192,6 +192,8 @@ The event interface:: void (*notify_ha_event)(struct sas_ha_struct *, enum ha_event); void sas_notify_port_event(struct sas_phy *, enum port_event); void sas_notify_phy_event(struct sas_phy *, enum phy_event); + void sas_notify_port_event_gfp(struct sas_phy *, enum port_event, gfp_t); + void sas_notify_phy_event_gfp(struct sas_phy *, enum phy_event, gfp_t); The port notification:: diff --git a/drivers/scsi/libsas/sas_event.c b/drivers/scsi/libsas/sas_event.c index 112a1b76f63b1..ba266a17250ae 100644 --- a/drivers/scsi/libsas/sas_event.c +++ b/drivers/scsi/libsas/sas_event.c @@ -131,18 +131,15 @@ static void sas_phy_event_worker(struct work_struct *work) sas_free_event(ev); } -int sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event) +static int __sas_notify_port_event(struct asd_sas_phy *phy, + enum port_event event, + struct asd_sas_event *ev) { - struct asd_sas_event *ev; struct sas_ha_struct *ha = phy->ha; int ret; BUG_ON(event >= PORT_NUM_EVENTS); - ev = sas_alloc_event(phy); - if (!ev) - return -ENOMEM; - INIT_SAS_EVENT(ev, sas_port_event_worker, phy, event); ret = sas_queue_event(event, &ev->work, ha); @@ -151,20 +148,41 @@ int sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event) return ret; } -EXPORT_SYMBOL_GPL(sas_notify_port_event); -int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event) +int sas_notify_port_event_gfp(struct asd_sas_phy *phy, enum port_event event, + gfp_t gfp_flags) { struct asd_sas_event *ev; - struct sas_ha_struct *ha = phy->ha; - int ret; - BUG_ON(event >= PHY_NUM_EVENTS); + ev = sas_alloc_event_gfp(phy, gfp_flags); + if (!ev) + return -ENOMEM; + + return __sas_notify_port_event(phy, event, ev); +} +EXPORT_SYMBOL_GPL(sas_notify_port_event_gfp); + +int sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event) +{ + struct asd_sas_event *ev; ev = sas_alloc_event(phy); if (!ev) return -ENOMEM; + return __sas_notify_port_event(phy, event, ev); +} +EXPORT_SYMBOL_GPL(sas_notify_port_event); + +static inline int __sas_notify_phy_event(struct asd_sas_phy *phy, + enum phy_event event, + struct asd_sas_event *ev) +{ + struct sas_ha_struct *ha = phy->ha; + int ret; + + BUG_ON(event >= PHY_NUM_EVENTS); + INIT_SAS_EVENT(ev, sas_phy_event_worker, phy, event); ret = sas_queue_event(event, &ev->work, ha); @@ -173,5 +191,28 @@ int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event) return ret; } -EXPORT_SYMBOL_GPL(sas_notify_phy_event); +int sas_notify_phy_event_gfp(struct asd_sas_phy *phy, enum phy_event event, + gfp_t gfp_flags) +{ + struct asd_sas_event *ev; + + ev = sas_alloc_event_gfp(phy, gfp_flags); + if (!ev) + return -ENOMEM; + + return __sas_notify_phy_event(phy, event, ev); +} +EXPORT_SYMBOL_GPL(sas_notify_phy_event_gfp); + +int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event) +{ + struct asd_sas_event *ev; + + ev = sas_alloc_event(phy); + if (!ev) + return -ENOMEM; + + return __sas_notify_phy_event(phy, event, ev); +} +EXPORT_SYMBOL_GPL(sas_notify_phy_event); diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c index 6dc2505d36af7..f8ae1f0f17d36 100644 --- a/drivers/scsi/libsas/sas_init.c +++ b/drivers/scsi/libsas/sas_init.c @@ -584,16 +584,15 @@ sas_domain_attach_transport(struct sas_domain_function_template *dft) } EXPORT_SYMBOL_GPL(sas_domain_attach_transport); - -struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy) +static struct asd_sas_event *__sas_alloc_event(struct asd_sas_phy *phy, + gfp_t gfp_flags) { struct asd_sas_event *event; - gfp_t flags = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL; struct sas_ha_struct *sas_ha = phy->ha; struct sas_internal *i = to_sas_internal(sas_ha->core.shost->transportt); - event = kmem_cache_zalloc(sas_event_cache, flags); + event = kmem_cache_zalloc(sas_event_cache, gfp_flags); if (!event) return NULL; @@ -604,7 +603,8 @@ struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy) if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) { pr_notice("The phy%d bursting events, shut it down.\n", phy->id); - sas_notify_phy_event(phy, PHYE_SHUTDOWN); + sas_notify_phy_event_gfp(phy, PHYE_SHUTDOWN, + gfp_flags); } } else { /* Do not support PHY control, stop allocating events */ @@ -618,6 +618,17 @@ struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy) return event; } +struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy) +{ + return __sas_alloc_event(phy, in_interrupt() ? GFP_ATOMIC : GFP_KERNEL); +} + +struct asd_sas_event *sas_alloc_event_gfp(struct asd_sas_phy *phy, + gfp_t gfp_flags) +{ + return __sas_alloc_event(phy, gfp_flags); +} + void sas_free_event(struct asd_sas_event *event) { struct asd_sas_phy *phy = event->phy; diff --git a/drivers/scsi/libsas/sas_internal.h b/drivers/scsi/libsas/sas_internal.h index 53ea32ed17a75..52e09c3e2b50d 100644 --- a/drivers/scsi/libsas/sas_internal.h +++ b/drivers/scsi/libsas/sas_internal.h @@ -49,6 +49,8 @@ int sas_register_phys(struct sas_ha_struct *sas_ha); void sas_unregister_phys(struct sas_ha_struct *sas_ha); struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy); +struct asd_sas_event *sas_alloc_event_gfp(struct asd_sas_phy *phy, + gfp_t gfp_flags); void sas_free_event(struct asd_sas_event *event); int sas_register_ports(struct sas_ha_struct *sas_ha); @@ -77,6 +79,8 @@ int sas_smp_phy_control(struct domain_device *dev, int phy_id, int sas_smp_get_phy_events(struct sas_phy *phy); int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event); +int sas_notify_phy_event_gfp(struct asd_sas_phy *phy, enum phy_event event, + gfp_t flags); void sas_device_set_phy(struct domain_device *dev, struct sas_port *port); struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy); struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id); diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h index 3387149502e9a..e6a43163ab5b7 100644 --- a/include/scsi/libsas.h +++ b/include/scsi/libsas.h @@ -704,5 +704,9 @@ int sas_request_addr(struct Scsi_Host *shost, u8 *addr); int sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event); int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event); +int sas_notify_port_event_gfp(struct asd_sas_phy *phy, enum port_event event, + gfp_t gfp_flags); +int sas_notify_phy_event_gfp(struct asd_sas_phy *phy, enum phy_event event, + gfp_t gfp_flags); #endif /* _SASLIB_H_ */