Re: [PATCH 6/7] ocxl: afu_irq only deals with IRQ IDs, not offsets

From: Greg Kurz
Date: Fri Mar 15 2019 - 10:02:20 EST


On Wed, 13 Mar 2019 15:15:21 +1100
"Alastair D'Silva" <alastair@xxxxxxxxxxx> wrote:

> From: Alastair D'Silva <alastair@xxxxxxxxxxx>
>
> The use of offsets is required only in the frontend, so alter
> the IRQ API to only work with IRQ IDs in the backend.
>
> Signed-off-by: Alastair D'Silva <alastair@xxxxxxxxxxx>
> ---
> drivers/misc/ocxl/afu_irq.c | 31 +++++++++++++------------------
> drivers/misc/ocxl/context.c | 7 +++++--
> drivers/misc/ocxl/file.c | 13 ++++++++-----
> drivers/misc/ocxl/ocxl_internal.h | 10 ++++++----
> drivers/misc/ocxl/trace.h | 12 ++++--------
> 5 files changed, 36 insertions(+), 37 deletions(-)
>
> diff --git a/drivers/misc/ocxl/afu_irq.c b/drivers/misc/ocxl/afu_irq.c
> index 11ab996657a2..1885c472df58 100644
> --- a/drivers/misc/ocxl/afu_irq.c
> +++ b/drivers/misc/ocxl/afu_irq.c
> @@ -14,14 +14,14 @@ struct afu_irq {
> struct eventfd_ctx *ev_ctx;
> };
>
> -static int irq_offset_to_id(struct ocxl_context *ctx, u64 offset)
> +int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset)
> {
> return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT;
> }
>
> -static u64 irq_id_to_offset(struct ocxl_context *ctx, int id)
> +u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id)
> {
> - return ctx->afu->irq_base_offset + (id << PAGE_SHIFT);
> + return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT);
> }
>
> static irqreturn_t afu_irq_handler(int virq, void *data)
> @@ -69,7 +69,7 @@ static void release_afu_irq(struct afu_irq *irq)
> kfree(irq->name);
> }
>
> -int ocxl_afu_irq_alloc(struct ocxl_context *ctx, u64 *irq_offset)
> +int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id)
> {
> struct afu_irq *irq;
> int rc;
> @@ -101,10 +101,7 @@ int ocxl_afu_irq_alloc(struct ocxl_context *ctx, u64 *irq_offset)
> if (rc)
> goto err_alloc;
>
> - *irq_offset = irq_id_to_offset(ctx, irq->id);

This should be replaced by:

*irq_id = irq->id;

> -
> - trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq,
> - *irq_offset);
> + trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq);
> mutex_unlock(&ctx->irq_lock);
> return 0;
>
> @@ -123,7 +120,7 @@ static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)
> trace_ocxl_afu_irq_free(ctx->pasid, irq->id);
> if (ctx->mapping)
> unmap_mapping_range(ctx->mapping,
> - irq_id_to_offset(ctx, irq->id),
> + ocxl_irq_id_to_offset(ctx, irq->id),
> 1 << PAGE_SHIFT, 1);
> release_afu_irq(irq);
> if (irq->ev_ctx)
> @@ -132,14 +129,13 @@ static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)
> kfree(irq);
> }
>
> -int ocxl_afu_irq_free(struct ocxl_context *ctx, u64 irq_offset)
> +int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id)
> {
> struct afu_irq *irq;
> - int id = irq_offset_to_id(ctx, irq_offset);
>
> mutex_lock(&ctx->irq_lock);
>
> - irq = idr_find(&ctx->irq_idr, id);
> + irq = idr_find(&ctx->irq_idr, irq_id);
> if (!irq) {
> mutex_unlock(&ctx->irq_lock);
> return -EINVAL;
> @@ -161,14 +157,14 @@ void ocxl_afu_irq_free_all(struct ocxl_context *ctx)
> mutex_unlock(&ctx->irq_lock);
> }
>
> -int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, u64 irq_offset, int eventfd)
> +int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, int irq_id, int eventfd)
> {
> struct afu_irq *irq;
> struct eventfd_ctx *ev_ctx;
> - int rc = 0, id = irq_offset_to_id(ctx, irq_offset);
> + int rc = 0;
>
> mutex_lock(&ctx->irq_lock);
> - irq = idr_find(&ctx->irq_idr, id);
> + irq = idr_find(&ctx->irq_idr, irq_id);
> if (!irq) {
> rc = -EINVAL;
> goto unlock;
> @@ -186,14 +182,13 @@ int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, u64 irq_offset, int eventfd)
> return rc;
> }
>
> -u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, u64 irq_offset)
> +u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id)
> {
> struct afu_irq *irq;
> - int id = irq_offset_to_id(ctx, irq_offset);
> u64 addr = 0;
>
> mutex_lock(&ctx->irq_lock);
> - irq = idr_find(&ctx->irq_idr, id);
> + irq = idr_find(&ctx->irq_idr, irq_id);
> if (irq)
> addr = irq->trigger_page;
> mutex_unlock(&ctx->irq_lock);
> diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c
> index 9a37e9632cd9..c04887591837 100644
> --- a/drivers/misc/ocxl/context.c
> +++ b/drivers/misc/ocxl/context.c
> @@ -93,8 +93,9 @@ static vm_fault_t map_afu_irq(struct vm_area_struct *vma, unsigned long address,
> u64 offset, struct ocxl_context *ctx)
> {
> u64 trigger_addr;
> + int irq_id = ocxl_irq_offset_to_id(ctx, offset);
>
> - trigger_addr = ocxl_afu_irq_get_addr(ctx, offset);
> + trigger_addr = ocxl_afu_irq_get_addr(ctx, irq_id);
> if (!trigger_addr)
> return VM_FAULT_SIGBUS;
>
> @@ -154,12 +155,14 @@ static const struct vm_operations_struct ocxl_vmops = {
> static int check_mmap_afu_irq(struct ocxl_context *ctx,
> struct vm_area_struct *vma)
> {
> + int irq_id = ocxl_irq_offset_to_id(ctx, vma->vm_pgoff << PAGE_SHIFT);
> +
> /* only one page */
> if (vma_pages(vma) != 1)
> return -EINVAL;
>
> /* check offset validty */
> - if (!ocxl_afu_irq_get_addr(ctx, vma->vm_pgoff << PAGE_SHIFT))
> + if (!ocxl_afu_irq_get_addr(ctx, irq_id))
> return -EINVAL;
>
> /*
> diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
> index 424bb0b40afb..d28618c161de 100644
> --- a/drivers/misc/ocxl/file.c
> +++ b/drivers/misc/ocxl/file.c
> @@ -197,6 +197,7 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
> {
> struct ocxl_context *ctx = file->private_data;
> struct ocxl_ioctl_irq_fd irq_fd;
> + int irq_id;
> u64 irq_offset;
> long rc;
> bool closed;
> @@ -218,12 +219,13 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
> break;
>
> case OCXL_IOCTL_IRQ_ALLOC:
> - rc = ocxl_afu_irq_alloc(ctx, &irq_offset);
> + rc = ocxl_afu_irq_alloc(ctx, &irq_id);
> if (!rc) {
> + irq_offset = ocxl_irq_id_to_offset(ctx, irq_id);
> rc = copy_to_user((u64 __user *) args, &irq_offset,
> sizeof(irq_offset));
> if (rc) {
> - ocxl_afu_irq_free(ctx, irq_offset);
> + ocxl_afu_irq_free(ctx, irq_id);
> return -EFAULT;
> }
> }
> @@ -234,7 +236,8 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
> sizeof(irq_offset));
> if (rc)
> return -EFAULT;
> - rc = ocxl_afu_irq_free(ctx, irq_offset);
> + irq_id = ocxl_irq_offset_to_id(ctx, irq_offset);
> + rc = ocxl_afu_irq_free(ctx, irq_id);
> break;
>
> case OCXL_IOCTL_IRQ_SET_FD:
> @@ -244,8 +247,8 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
> return -EFAULT;
> if (irq_fd.reserved)
> return -EINVAL;
> - rc = ocxl_afu_irq_set_fd(ctx, irq_fd.irq_offset,
> - irq_fd.eventfd);
> + irq_id = ocxl_irq_offset_to_id(ctx, irq_fd.irq_offset);
> + rc = ocxl_afu_irq_set_fd(ctx, irq_id, irq_fd.eventfd);
> break;
>
> case OCXL_IOCTL_GET_METADATA:
> diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h
> index 4fc7e9597ede..871155b464da 100644
> --- a/drivers/misc/ocxl/ocxl_internal.h
> +++ b/drivers/misc/ocxl/ocxl_internal.h
> @@ -140,12 +140,14 @@ void ocxl_context_detach_all(struct ocxl_afu *afu);
> int ocxl_sysfs_register_afu(struct ocxl_afu *afu);
> void ocxl_sysfs_unregister_afu(struct ocxl_afu *afu);
>
> -int ocxl_afu_irq_alloc(struct ocxl_context *ctx, u64 *irq_offset);
> -int ocxl_afu_irq_free(struct ocxl_context *ctx, u64 irq_offset);
> +int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset);
> +u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id);
> +int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id);
> +int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id);
> void ocxl_afu_irq_free_all(struct ocxl_context *ctx);
> -int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, u64 irq_offset,
> +int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, int irq_id,
> int eventfd);
> -u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, u64 irq_offset);
> +u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id);
>
> /**
> * Free an AFU
> diff --git a/drivers/misc/ocxl/trace.h b/drivers/misc/ocxl/trace.h
> index 68bf2f173a1a..a081e644f5f3 100644
> --- a/drivers/misc/ocxl/trace.h
> +++ b/drivers/misc/ocxl/trace.h
> @@ -107,16 +107,14 @@ DEFINE_EVENT(ocxl_fault_handler, ocxl_fault_ack,
> );
>
> TRACE_EVENT(ocxl_afu_irq_alloc,
> - TP_PROTO(int pasid, int irq_id, unsigned int virq, int hw_irq,
> - u64 irq_offset),
> - TP_ARGS(pasid, irq_id, virq, hw_irq, irq_offset),
> + TP_PROTO(int pasid, int irq_id, unsigned int virq, int hw_irq),
> + TP_ARGS(pasid, irq_id, virq, hw_irq),
>
> TP_STRUCT__entry(
> __field(int, pasid)
> __field(int, irq_id)
> __field(unsigned int, virq)
> __field(int, hw_irq)
> - __field(u64, irq_offset)
> ),
>
> TP_fast_assign(
> @@ -124,15 +122,13 @@ TRACE_EVENT(ocxl_afu_irq_alloc,
> __entry->irq_id = irq_id;
> __entry->virq = virq;
> __entry->hw_irq = hw_irq;
> - __entry->irq_offset = irq_offset;
> ),
>
> - TP_printk("pasid=%#x irq_id=%d virq=%u hw_irq=%d irq_offset=%#llx",
> + TP_printk("pasid=%#x irq_id=%d virq=%u hw_irq=%d",
> __entry->pasid,
> __entry->irq_id,
> __entry->virq,
> - __entry->hw_irq,
> - __entry->irq_offset
> + __entry->hw_irq
> )
> );
>