diff options
author | Alastair D'Silva <alastair@d-silva.org> | 2018-05-11 16:13:01 +1000 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-06-03 20:40:32 +1000 |
commit | e948e06fc63a1c1e36ec4c8e5c510b881ff19c26 (patch) | |
tree | 59a49968a3211c2708b135d6c79f97af3c9b2cb1 /drivers | |
parent | 19df39581ce99eb1fcfb119945810c9c5bc3f8d4 (diff) | |
download | linux-e948e06fc63a1c1e36ec4c8e5c510b881ff19c26.tar.gz linux-e948e06fc63a1c1e36ec4c8e5c510b881ff19c26.tar.bz2 linux-e948e06fc63a1c1e36ec4c8e5c510b881ff19c26.zip |
ocxl: Expose the thread_id needed for wait on POWER9
In order to successfully issue as_notify, an AFU needs to know the TID
to notify, which in turn means that this information should be
available in userspace so it can be communicated to the AFU.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/misc/ocxl/context.c | 5 | ||||
-rw-r--r-- | drivers/misc/ocxl/file.c | 53 | ||||
-rw-r--r-- | drivers/misc/ocxl/link.c | 36 | ||||
-rw-r--r-- | drivers/misc/ocxl/ocxl_internal.h | 1 |
4 files changed, 94 insertions, 1 deletions
diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c index 909e8807824a..95f74623113e 100644 --- a/drivers/misc/ocxl/context.c +++ b/drivers/misc/ocxl/context.c @@ -34,6 +34,8 @@ int ocxl_context_init(struct ocxl_context *ctx, struct ocxl_afu *afu, mutex_init(&ctx->xsl_error_lock); mutex_init(&ctx->irq_lock); idr_init(&ctx->irq_idr); + ctx->tidr = 0; + /* * Keep a reference on the AFU to make sure it's valid for the * duration of the life of the context @@ -65,6 +67,7 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr) { int rc; + // Locks both status & tidr mutex_lock(&ctx->status_mutex); if (ctx->status != OPENED) { rc = -EIO; @@ -72,7 +75,7 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr) } rc = ocxl_link_add_pe(ctx->afu->fn->link, ctx->pasid, - current->mm->context.id, 0, amr, current->mm, + current->mm->context.id, ctx->tidr, amr, current->mm, xsl_fault_error, ctx); if (rc) goto out; diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c index 038509e5d031..eb409a469f21 100644 --- a/drivers/misc/ocxl/file.c +++ b/drivers/misc/ocxl/file.c @@ -5,6 +5,8 @@ #include <linux/sched/signal.h> #include <linux/uaccess.h> #include <uapi/misc/ocxl.h> +#include <asm/reg.h> +#include <asm/switch_to.h> #include "ocxl_internal.h" @@ -123,11 +125,55 @@ static long afu_ioctl_get_metadata(struct ocxl_context *ctx, return 0; } +#ifdef CONFIG_PPC64 +static long afu_ioctl_enable_p9_wait(struct ocxl_context *ctx, + struct ocxl_ioctl_p9_wait __user *uarg) +{ + struct ocxl_ioctl_p9_wait arg; + + memset(&arg, 0, sizeof(arg)); + + if (cpu_has_feature(CPU_FTR_P9_TIDR)) { + enum ocxl_context_status status; + + // Locks both status & tidr + mutex_lock(&ctx->status_mutex); + if (!ctx->tidr) { + if (set_thread_tidr(current)) + return -ENOENT; + + ctx->tidr = current->thread.tidr; + } + + status = ctx->status; + mutex_unlock(&ctx->status_mutex); + + if (status == ATTACHED) { + int rc; + struct link *link = ctx->afu->fn->link; + + rc = ocxl_link_update_pe(link, ctx->pasid, ctx->tidr); + if (rc) + return rc; + } + + arg.thread_id = ctx->tidr; + } else + return -ENOENT; + + if (copy_to_user(uarg, &arg, sizeof(arg))) + return -EFAULT; + + return 0; +} +#endif + #define CMD_STR(x) (x == OCXL_IOCTL_ATTACH ? "ATTACH" : \ x == OCXL_IOCTL_IRQ_ALLOC ? "IRQ_ALLOC" : \ x == OCXL_IOCTL_IRQ_FREE ? "IRQ_FREE" : \ x == OCXL_IOCTL_IRQ_SET_FD ? "IRQ_SET_FD" : \ x == OCXL_IOCTL_GET_METADATA ? "GET_METADATA" : \ + x == OCXL_IOCTL_ENABLE_P9_WAIT ? "ENABLE_P9_WAIT" : \ "UNKNOWN") static long afu_ioctl(struct file *file, unsigned int cmd, @@ -186,6 +232,13 @@ static long afu_ioctl(struct file *file, unsigned int cmd, (struct ocxl_ioctl_metadata __user *) args); break; +#ifdef CONFIG_PPC64 + case OCXL_IOCTL_ENABLE_P9_WAIT: + rc = afu_ioctl_enable_p9_wait(ctx, + (struct ocxl_ioctl_p9_wait __user *) args); + break; +#endif + default: rc = -EINVAL; } diff --git a/drivers/misc/ocxl/link.c b/drivers/misc/ocxl/link.c index 656e8610eec2..88876ae8f330 100644 --- a/drivers/misc/ocxl/link.c +++ b/drivers/misc/ocxl/link.c @@ -544,6 +544,42 @@ unlock: } EXPORT_SYMBOL_GPL(ocxl_link_add_pe); +int ocxl_link_update_pe(void *link_handle, int pasid, __u16 tid) +{ + struct link *link = (struct link *) link_handle; + struct spa *spa = link->spa; + struct ocxl_process_element *pe; + int pe_handle, rc; + + if (pasid > SPA_PASID_MAX) + return -EINVAL; + + pe_handle = pasid & SPA_PE_MASK; + pe = spa->spa_mem + pe_handle; + + mutex_lock(&spa->spa_lock); + + pe->tid = tid; + + /* + * The barrier makes sure the PE is updated + * before we clear the NPU context cache below, so that the + * old PE cannot be reloaded erroneously. + */ + mb(); + + /* + * hook to platform code + * On powerpc, the entry needs to be cleared from the context + * cache of the NPU. + */ + rc = pnv_ocxl_spa_remove_pe_from_cache(link->platform_data, pe_handle); + WARN_ON(rc); + + mutex_unlock(&spa->spa_lock); + return rc; +} + int ocxl_link_remove_pe(void *link_handle, int pasid) { struct link *link = (struct link *) link_handle; diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h index 5d421824afd9..a32f2151029f 100644 --- a/drivers/misc/ocxl/ocxl_internal.h +++ b/drivers/misc/ocxl/ocxl_internal.h @@ -77,6 +77,7 @@ struct ocxl_context { struct ocxl_xsl_error xsl_error; struct mutex irq_lock; struct idr irq_idr; + u16 tidr; // Thread ID used for P9 wait implementation }; struct ocxl_process_element { |