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Violators will be prosecuted for from ; Thu, 14 Jun 2018 17:07:02 +0100 Subject: Re: [PATCH] misc: ocxl: Change return type for fault handler To: Souptick Joarder , willy@infradead.org, fbarrat@linux.vnet.ibm.com, andrew.donnellan@au1.ibm.com, arnd@arndb.de, gregkh@linuxfoundation.org Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, sabyasachi.linux@gmail.com, brajeswar.linux@gmail.com References: <20180611202904.GA25538@jordon-HP-15-Notebook-PC> From: Frederic Barrat Date: Thu, 14 Jun 2018 18:06:56 +0200 MIME-Version: 1.0 In-Reply-To: <20180611202904.GA25538@jordon-HP-15-Notebook-PC> Content-Type: text/plain; charset=utf-8; format=flowed Message-Id: <5c6942da-c847-c53a-a571-4ec96f2a993d@linux.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Le 11/06/2018 à 22:29, Souptick Joarder a écrit : > Use new return type vm_fault_t for fault handler. For > now, this is just documenting that the function returns > a VM_FAULT value rather than an errno. Once all instances > are converted, vm_fault_t will become a distinct type. > > Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t") > > There is an existing bug when vm_insert_pfn() can return > ENOMEM which was ignored and VM_FAULT_NOPAGE returned as > default. The new inline vmf_insert_pfn() has removed > this inefficiency by returning correct vm_fault_ type. > > Signed-off-by: Souptick Joarder > --- Thanks! Tested and Acked-by: Frederic Barrat > drivers/misc/ocxl/context.c | 22 +++++++++++----------- > drivers/misc/ocxl/sysfs.c | 5 ++--- > 2 files changed, 13 insertions(+), 14 deletions(-) > > diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c > index 909e880..98daf91 100644 > --- a/drivers/misc/ocxl/context.c > +++ b/drivers/misc/ocxl/context.c > @@ -83,7 +83,7 @@ int ocxl_context_attach(struct ocxl_context *ctx, u64 amr) > return rc; > } > > -static int map_afu_irq(struct vm_area_struct *vma, unsigned long address, > +static vm_fault_t map_afu_irq(struct vm_area_struct *vma, unsigned long address, > u64 offset, struct ocxl_context *ctx) > { > u64 trigger_addr; > @@ -92,15 +92,15 @@ static int map_afu_irq(struct vm_area_struct *vma, unsigned long address, > if (!trigger_addr) > return VM_FAULT_SIGBUS; > > - vm_insert_pfn(vma, address, trigger_addr >> PAGE_SHIFT); > - return VM_FAULT_NOPAGE; > + return vmf_insert_pfn(vma, address, trigger_addr >> PAGE_SHIFT); > } > > -static int map_pp_mmio(struct vm_area_struct *vma, unsigned long address, > +static vm_fault_t map_pp_mmio(struct vm_area_struct *vma, unsigned long address, > u64 offset, struct ocxl_context *ctx) > { > u64 pp_mmio_addr; > int pasid_off; > + vm_fault_t ret; > > if (offset >= ctx->afu->config.pp_mmio_stride) > return VM_FAULT_SIGBUS; > @@ -118,27 +118,27 @@ static int map_pp_mmio(struct vm_area_struct *vma, unsigned long address, > pasid_off * ctx->afu->config.pp_mmio_stride + > offset; > > - vm_insert_pfn(vma, address, pp_mmio_addr >> PAGE_SHIFT); > + ret = vmf_insert_pfn(vma, address, pp_mmio_addr >> PAGE_SHIFT); > mutex_unlock(&ctx->status_mutex); > - return VM_FAULT_NOPAGE; > + return ret; > } > > -static int ocxl_mmap_fault(struct vm_fault *vmf) > +static vm_fault_t ocxl_mmap_fault(struct vm_fault *vmf) > { > struct vm_area_struct *vma = vmf->vma; > struct ocxl_context *ctx = vma->vm_file->private_data; > u64 offset; > - int rc; > + vm_fault_t ret; > > offset = vmf->pgoff << PAGE_SHIFT; > pr_debug("%s: pasid %d address 0x%lx offset 0x%llx\n", __func__, > ctx->pasid, vmf->address, offset); > > if (offset < ctx->afu->irq_base_offset) > - rc = map_pp_mmio(vma, vmf->address, offset, ctx); > + ret = map_pp_mmio(vma, vmf->address, offset, ctx); > else > - rc = map_afu_irq(vma, vmf->address, offset, ctx); > - return rc; > + ret = map_afu_irq(vma, vmf->address, offset, ctx); > + return ret; > } > > static const struct vm_operations_struct ocxl_vmops = { > diff --git a/drivers/misc/ocxl/sysfs.c b/drivers/misc/ocxl/sysfs.c > index d9753a1..0ab1fd1 100644 > --- a/drivers/misc/ocxl/sysfs.c > +++ b/drivers/misc/ocxl/sysfs.c > @@ -64,7 +64,7 @@ static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj, > return count; > } > > -static int global_mmio_fault(struct vm_fault *vmf) > +static vm_fault_t global_mmio_fault(struct vm_fault *vmf) > { > struct vm_area_struct *vma = vmf->vma; > struct ocxl_afu *afu = vma->vm_private_data; > @@ -75,8 +75,7 @@ static int global_mmio_fault(struct vm_fault *vmf) > > offset = vmf->pgoff; > offset += (afu->global_mmio_start >> PAGE_SHIFT); > - vm_insert_pfn(vma, vmf->address, offset); > - return VM_FAULT_NOPAGE; > + return vmf_insert_pfn(vma, vmf->address, offset); > } > > static const struct vm_operations_struct global_mmio_vmops = { >