diff options
| -rw-r--r-- | arch/powerpc/include/asm/mmu_context.h | 46 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context.c | 9 | ||||
| -rw-r--r-- | drivers/misc/cxl/api.c | 16 | ||||
| -rw-r--r-- | drivers/misc/cxl/context.c | 3 | ||||
| -rw-r--r-- | drivers/misc/cxl/file.c | 24 |
5 files changed, 84 insertions, 14 deletions
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index 309592589e30..a0d7145d6cd2 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -77,6 +77,52 @@ extern void switch_cop(struct mm_struct *next); extern int use_cop(unsigned long acop, struct mm_struct *mm); extern void drop_cop(unsigned long acop, struct mm_struct *mm); +#ifdef CONFIG_PPC_BOOK3S_64 +static inline void inc_mm_active_cpus(struct mm_struct *mm) +{ + atomic_inc(&mm->context.active_cpus); +} + +static inline void dec_mm_active_cpus(struct mm_struct *mm) +{ + atomic_dec(&mm->context.active_cpus); +} + +static inline void mm_context_add_copro(struct mm_struct *mm) +{ + /* + * On hash, should only be called once over the lifetime of + * the context, as we can't decrement the active cpus count + * and flush properly for the time being. + */ + inc_mm_active_cpus(mm); +} + +static inline void mm_context_remove_copro(struct mm_struct *mm) +{ + /* + * Need to broadcast a global flush of the full mm before + * decrementing active_cpus count, as the next TLBI may be + * local and the nMMU and/or PSL need to be cleaned up. + * Should be rare enough so that it's acceptable. + * + * Skip on hash, as we don't know how to do the proper flush + * for the time being. Invalidations will remain global if + * used on hash. + */ + if (radix_enabled()) { + flush_all_mm(mm); + dec_mm_active_cpus(mm); + } +} +#else +static inline void inc_mm_active_cpus(struct mm_struct *mm) { } +static inline void dec_mm_active_cpus(struct mm_struct *mm) { } +static inline void mm_context_add_copro(struct mm_struct *mm) { } +static inline void mm_context_remove_copro(struct mm_struct *mm) { } +#endif + + extern void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk); diff --git a/arch/powerpc/mm/mmu_context.c b/arch/powerpc/mm/mmu_context.c index 0f613bc63c50..d60a62bf4fc7 100644 --- a/arch/powerpc/mm/mmu_context.c +++ b/arch/powerpc/mm/mmu_context.c @@ -34,15 +34,6 @@ static inline void switch_mm_pgdir(struct task_struct *tsk, struct mm_struct *mm) { } #endif -#ifdef CONFIG_PPC_BOOK3S_64 -static inline void inc_mm_active_cpus(struct mm_struct *mm) -{ - atomic_inc(&mm->context.active_cpus); -} -#else -static inline void inc_mm_active_cpus(struct mm_struct *mm) { } -#endif - void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) { diff --git a/drivers/misc/cxl/api.c b/drivers/misc/cxl/api.c index a0c44d16bf30..7c11bad5cded 100644 --- a/drivers/misc/cxl/api.c +++ b/drivers/misc/cxl/api.c @@ -15,6 +15,7 @@ #include <linux/module.h> #include <linux/mount.h> #include <linux/sched/mm.h> +#include <linux/mmu_context.h> #include "cxl.h" @@ -331,9 +332,12 @@ int cxl_start_context(struct cxl_context *ctx, u64 wed, /* ensure this mm_struct can't be freed */ cxl_context_mm_count_get(ctx); - /* decrement the use count */ - if (ctx->mm) + if (ctx->mm) { + /* decrement the use count from above */ mmput(ctx->mm); + /* make TLBIs for this context global */ + mm_context_add_copro(ctx->mm); + } } /* @@ -342,13 +346,19 @@ int cxl_start_context(struct cxl_context *ctx, u64 wed, */ cxl_ctx_get(); + /* See the comment in afu_ioctl_start_work() */ + smp_mb(); + if ((rc = cxl_ops->attach_process(ctx, kernel, wed, 0))) { put_pid(ctx->pid); ctx->pid = NULL; cxl_adapter_context_put(ctx->afu->adapter); cxl_ctx_put(); - if (task) + if (task) { cxl_context_mm_count_put(ctx); + if (ctx->mm) + mm_context_remove_copro(ctx->mm); + } goto out; } diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c index 8c32040b9c09..12a41b2753f0 100644 --- a/drivers/misc/cxl/context.c +++ b/drivers/misc/cxl/context.c @@ -18,6 +18,7 @@ #include <linux/slab.h> #include <linux/idr.h> #include <linux/sched/mm.h> +#include <linux/mmu_context.h> #include <asm/cputable.h> #include <asm/current.h> #include <asm/copro.h> @@ -267,6 +268,8 @@ int __detach_context(struct cxl_context *ctx) /* Decrease the mm count on the context */ cxl_context_mm_count_put(ctx); + if (ctx->mm) + mm_context_remove_copro(ctx->mm); ctx->mm = NULL; return 0; diff --git a/drivers/misc/cxl/file.c b/drivers/misc/cxl/file.c index 4bfad9f6dc9f..76c0b0ca9388 100644 --- a/drivers/misc/cxl/file.c +++ b/drivers/misc/cxl/file.c @@ -19,6 +19,7 @@ #include <linux/mm.h> #include <linux/slab.h> #include <linux/sched/mm.h> +#include <linux/mmu_context.h> #include <asm/cputable.h> #include <asm/current.h> #include <asm/copro.h> @@ -220,9 +221,12 @@ static long afu_ioctl_start_work(struct cxl_context *ctx, /* ensure this mm_struct can't be freed */ cxl_context_mm_count_get(ctx); - /* decrement the use count */ - if (ctx->mm) + if (ctx->mm) { + /* decrement the use count from above */ mmput(ctx->mm); + /* make TLBIs for this context global */ + mm_context_add_copro(ctx->mm); + } /* * Increment driver use count. Enables global TLBIs for hash @@ -230,6 +234,20 @@ static long afu_ioctl_start_work(struct cxl_context *ctx, */ cxl_ctx_get(); + /* + * A barrier is needed to make sure all TLBIs are global + * before we attach and the context starts being used by the + * adapter. + * + * Needed after mm_context_add_copro() for radix and + * cxl_ctx_get() for hash/p8. + * + * The barrier should really be mb(), since it involves a + * device. However, it's only useful when we have local + * vs. global TLBIs, i.e SMP=y. So keep smp_mb(). + */ + smp_mb(); + trace_cxl_attach(ctx, work.work_element_descriptor, work.num_interrupts, amr); if ((rc = cxl_ops->attach_process(ctx, false, work.work_element_descriptor, @@ -240,6 +258,8 @@ static long afu_ioctl_start_work(struct cxl_context *ctx, ctx->pid = NULL; cxl_ctx_put(); cxl_context_mm_count_put(ctx); + if (ctx->mm) + mm_context_remove_copro(ctx->mm); goto out; } |