lkml.org 
[lkml]   [2019]   [Apr]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v4 6/7] ocxl: move event_fd handling to frontend
    From
    Date


    Le 27/03/2019 à 06:31, Alastair D'Silva a écrit :
    > From: Alastair D'Silva <alastair@d-silva.org>
    >
    > Event_fd is only used in the driver frontend, so it does not
    > need to exist in the backend code. Relocate it to the frontend
    > and provide an opaque mechanism for consumers instead.
    >
    > Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
    > ---


    Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>


    > drivers/misc/ocxl/afu_irq.c | 74 ++++++++++++++++++-------------
    > drivers/misc/ocxl/file.c | 22 ++++++++-
    > drivers/misc/ocxl/ocxl_internal.h | 5 ---
    > include/misc/ocxl.h | 46 +++++++++++++++++++
    > 4 files changed, 109 insertions(+), 38 deletions(-)
    >
    > diff --git a/drivers/misc/ocxl/afu_irq.c b/drivers/misc/ocxl/afu_irq.c
    > index 2d410cd6f817..70f8f1c3929d 100644
    > --- a/drivers/misc/ocxl/afu_irq.c
    > +++ b/drivers/misc/ocxl/afu_irq.c
    > @@ -1,7 +1,7 @@
    > // SPDX-License-Identifier: GPL-2.0+
    > // Copyright 2017 IBM Corp.
    > #include <linux/interrupt.h>
    > -#include <linux/eventfd.h>
    > +#include <asm/pnv-ocxl.h>
    > #include "ocxl_internal.h"
    > #include "trace.h"
    >
    > @@ -11,7 +11,9 @@ struct afu_irq {
    > unsigned int virq;
    > char *name;
    > u64 trigger_page;
    > - struct eventfd_ctx *ev_ctx;
    > + irqreturn_t (*handler)(void *private);
    > + void (*free_private)(void *private);
    > + void *private;
    > };
    >
    > int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset)
    > @@ -24,14 +26,44 @@ u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id)
    > return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT);
    > }
    >
    > +int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
    > + irqreturn_t (*handler)(void *private),
    > + void (*free_private)(void *private),
    > + void *private)
    > +{
    > + struct afu_irq *irq;
    > + int rc;
    > +
    > + mutex_lock(&ctx->irq_lock);
    > + irq = idr_find(&ctx->irq_idr, irq_id);
    > + if (!irq) {
    > + rc = -EINVAL;
    > + goto unlock;
    > + }
    > +
    > + irq->handler = handler;
    > + irq->private = private;
    > + irq->free_private = free_private;
    > +
    > + rc = 0;
    > + // Fall through to unlock
    > +
    > +unlock:
    > + mutex_unlock(&ctx->irq_lock);
    > + return rc;
    > +}
    > +EXPORT_SYMBOL_GPL(ocxl_irq_set_handler);
    > +
    > static irqreturn_t afu_irq_handler(int virq, void *data)
    > {
    > struct afu_irq *irq = (struct afu_irq *) data;
    >
    > trace_ocxl_afu_irq_receive(virq);
    > - if (irq->ev_ctx)
    > - eventfd_signal(irq->ev_ctx, 1);
    > - return IRQ_HANDLED;
    > +
    > + if (irq->handler)
    > + return irq->handler(irq->private);
    > +
    > + return IRQ_HANDLED; // Just drop it on the ground
    > }
    >
    > static int setup_afu_irq(struct ocxl_context *ctx, struct afu_irq *irq)
    > @@ -117,6 +149,7 @@ int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id)
    > kfree(irq);
    > return rc;
    > }
    > +EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc);
    >
    > static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)
    > {
    > @@ -126,8 +159,8 @@ static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)
    > ocxl_irq_id_to_offset(ctx, irq->id),
    > 1 << PAGE_SHIFT, 1);
    > release_afu_irq(irq);
    > - if (irq->ev_ctx)
    > - eventfd_ctx_put(irq->ev_ctx);
    > + if (irq->free_private)
    > + irq->free_private(irq->private);
    > ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq);
    > kfree(irq);
    > }
    > @@ -148,6 +181,7 @@ int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id)
    > mutex_unlock(&ctx->irq_lock);
    > return 0;
    > }
    > +EXPORT_SYMBOL_GPL(ocxl_afu_irq_free);
    >
    > void ocxl_afu_irq_free_all(struct ocxl_context *ctx)
    > {
    > @@ -160,31 +194,6 @@ 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, int irq_id, int eventfd)
    > -{
    > - struct afu_irq *irq;
    > - struct eventfd_ctx *ev_ctx;
    > - int rc = 0;
    > -
    > - mutex_lock(&ctx->irq_lock);
    > - irq = idr_find(&ctx->irq_idr, irq_id);
    > - if (!irq) {
    > - rc = -EINVAL;
    > - goto unlock;
    > - }
    > -
    > - ev_ctx = eventfd_ctx_fdget(eventfd);
    > - if (IS_ERR(ev_ctx)) {
    > - rc = -EINVAL;
    > - goto unlock;
    > - }
    > -
    > - irq->ev_ctx = ev_ctx;
    > -unlock:
    > - mutex_unlock(&ctx->irq_lock);
    > - return rc;
    > -}
    > -
    > u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id)
    > {
    > struct afu_irq *irq;
    > @@ -197,3 +206,4 @@ u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id)
    > mutex_unlock(&ctx->irq_lock);
    > return addr;
    > }
    > +EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr);
    > diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
    > index 7f5282a3af3a..8aa22893ed76 100644
    > --- a/drivers/misc/ocxl/file.c
    > +++ b/drivers/misc/ocxl/file.c
    > @@ -3,6 +3,7 @@
    > #include <linux/fs.h>
    > #include <linux/poll.h>
    > #include <linux/sched/signal.h>
    > +#include <linux/eventfd.h>
    > #include <linux/uaccess.h>
    > #include <uapi/misc/ocxl.h>
    > #include <asm/reg.h>
    > @@ -183,11 +184,27 @@ static long afu_ioctl_get_features(struct ocxl_context *ctx,
    > x == OCXL_IOCTL_GET_FEATURES ? "GET_FEATURES" : \
    > "UNKNOWN")
    >
    > +static irqreturn_t irq_handler(void *private)
    > +{
    > + struct eventfd_ctx *ev_ctx = private;
    > +
    > + eventfd_signal(ev_ctx, 1);
    > + return IRQ_HANDLED;
    > +}
    > +
    > +static void irq_free(void *private)
    > +{
    > + struct eventfd_ctx *ev_ctx = private;
    > +
    > + eventfd_ctx_put(ev_ctx);
    > +}
    > +
    > static long afu_ioctl(struct file *file, unsigned int cmd,
    > unsigned long args)
    > {
    > struct ocxl_context *ctx = file->private_data;
    > struct ocxl_ioctl_irq_fd irq_fd;
    > + struct eventfd_ctx *ev_ctx;
    > int irq_id;
    > u64 irq_offset;
    > long rc;
    > @@ -239,7 +256,10 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
    > if (irq_fd.reserved)
    > return -EINVAL;
    > irq_id = ocxl_irq_offset_to_id(ctx, irq_fd.irq_offset);
    > - rc = ocxl_afu_irq_set_fd(ctx, irq_id, irq_fd.eventfd);
    > + ev_ctx = eventfd_ctx_fdget(irq_fd.eventfd);
    > + if (!ev_ctx)
    > + return -EFAULT;
    > + rc = ocxl_irq_set_handler(ctx, irq_id, irq_handler, irq_free, ev_ctx);
    > break;
    >
    > case OCXL_IOCTL_GET_METADATA:
    > diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h
    > index 58969467bd5c..97415afd79f3 100644
    > --- a/drivers/misc/ocxl/ocxl_internal.h
    > +++ b/drivers/misc/ocxl/ocxl_internal.h
    > @@ -139,11 +139,6 @@ void ocxl_sysfs_unregister_afu(struct ocxl_file_info *info);
    >
    > 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, int irq_id,
    > - int eventfd);
    > -u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id);
    >
    > #endif /* _OCXL_INTERNAL_H_ */
    > diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
    > index e4704632eac5..dea93885a839 100644
    > --- a/include/misc/ocxl.h
    > +++ b/include/misc/ocxl.h
    > @@ -155,6 +155,52 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr,
    > */
    > int ocxl_context_detach(struct ocxl_context *ctx);
    >
    > +// AFU IRQs
    > +
    > +/**
    > + * Allocate an IRQ associated with an AFU context
    > + * @ctx: the AFU context
    > + * @irq_id: out, the IRQ ID
    > + *
    > + * Returns 0 on success, negative on failure
    > + */
    > +extern int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id);
    > +
    > +/**
    > + * Frees an IRQ associated with an AFU context
    > + * @ctx: the AFU context
    > + * @irq_id: the IRQ ID
    > + *
    > + * Returns 0 on success, negative on failure
    > + */
    > +extern int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id);
    > +
    > +/**
    > + * Gets the address of the trigger page for an IRQ
    > + * This can then be provided to an AFU which will write to that
    > + * page to trigger the IRQ.
    > + * @ctx: The AFU context that the IRQ is associated with
    > + * @irq_id: The IRQ ID
    > + *
    > + * returns the trigger page address, or 0 if the IRQ is not valid
    > + */
    > +extern u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id);
    > +
    > +/**
    > + * Provide a callback to be called when an IRQ is triggered
    > + * @ctx: The AFU context that the IRQ is associated with
    > + * @irq_id: The IRQ ID
    > + * @handler: the callback to be called when the IRQ is triggered
    > + * @free_private: the callback to be called when the IRQ is freed (may be NULL)
    > + * @private: Private data to be passed to the callbacks
    > + *
    > + * Returns 0 on success, negative on failure
    > + */
    > +int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
    > + irqreturn_t (*handler)(void *private),
    > + void (*free_private)(void *private),
    > + void *private);
    > +
    > // AFU Metadata
    >
    > /**
    >

    \
     
     \ /
      Last update: 2019-04-17 17:34    [W:4.417 / U:0.016 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site