From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zqxFL0bVjzF1Dl for ; Tue, 27 Feb 2018 09:24:05 +1100 (AEDT) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w1QMJRR6123250 for ; Mon, 26 Feb 2018 17:24:04 -0500 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 2gcqcvr455-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 26 Feb 2018 17:24:03 -0500 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 26 Feb 2018 17:24:02 -0500 From: Uma Krishnan To: linux-scsi@vger.kernel.org, James Bottomley , "Martin K. Petersen" , "Matthew R. Ochs" , "Manoj N. Kumar" Cc: linuxppc-dev@lists.ozlabs.org, Andrew Donnellan , Frederic Barrat , Christophe Lombard Subject: [PATCH v2 29/38] cxlflash: Support adapter context mmap and release Date: Mon, 26 Feb 2018 16:23:57 -0600 In-Reply-To: <1519683513-16731-1-git-send-email-ukrishn@linux.vnet.ibm.com> References: <1519683513-16731-1-git-send-email-ukrishn@linux.vnet.ibm.com> Message-Id: <1519683837-17799-1-git-send-email-ukrishn@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The cxlflash userspace API requires that users be able to mmap and release the adapter context. Support mapping by implementing the AFU mmap fop to map the context MMIO space and install the corresponding page table entry upon page fault. Similarly, implement the AFU release fop to terminate and clean up the context when invoked. Signed-off-by: Uma Krishnan Acked-by: Matthew R. Ochs --- drivers/scsi/cxlflash/ocxl_hw.c | 72 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c index a6ae9fd..226fd6b 100644 --- a/drivers/scsi/cxlflash/ocxl_hw.c +++ b/drivers/scsi/cxlflash/ocxl_hw.c @@ -1021,10 +1021,80 @@ static ssize_t afu_read(struct file *file, char __user *buf, size_t count, goto out; } +/** + * afu_release() - release and free the context + * @inode: File inode pointer. + * @file: File associated with the context. + * + * Return: 0 on success, -errno on failure + */ +static int afu_release(struct inode *inode, struct file *file) +{ + struct ocxlflash_context *ctx = file->private_data; + int i; + + /* Unmap and free the interrupts associated with the context */ + for (i = ctx->num_irqs; i >= 0; i--) + afu_unmap_irq(0, ctx, i, ctx); + free_afu_irqs(ctx); + + return ocxlflash_release_context(ctx); +} + +/** + * ocxlflash_mmap_fault() - mmap fault handler + * @vmf: VM fault associated with current fault. + * + * Return: 0 on success, -errno on failure + */ +static int ocxlflash_mmap_fault(struct vm_fault *vmf) +{ + struct vm_area_struct *vma = vmf->vma; + struct ocxlflash_context *ctx = vma->vm_file->private_data; + u64 mmio_area, offset; + + offset = vmf->pgoff << PAGE_SHIFT; + if (offset >= ctx->psn_size) + return VM_FAULT_SIGBUS; + + mmio_area = ctx->psn_phys; + mmio_area += offset; + + vm_insert_pfn(vma, vmf->address, mmio_area >> PAGE_SHIFT); + return VM_FAULT_NOPAGE; +} + +static const struct vm_operations_struct ocxlflash_vmops = { + .fault = ocxlflash_mmap_fault, +}; + +/** + * afu_mmap() - map the fault handler operations + * @file: File associated with the context. + * @vma: VM area associated with mapping. + * + * Return: 0 on success, -errno on failure + */ +static int afu_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct ocxlflash_context *ctx = file->private_data; + + if ((vma_pages(vma) + vma->vm_pgoff) > + (ctx->psn_size >> PAGE_SHIFT)) + return -EINVAL; + + vma->vm_flags |= VM_IO | VM_PFNMAP; + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + vma->vm_ops = &ocxlflash_vmops; + return 0; +} + static const struct file_operations ocxl_afu_fops = { .owner = THIS_MODULE, .poll = afu_poll, .read = afu_read, + .release = afu_release, + .mmap = afu_mmap, }; #define PATCH_FOPS(NAME) \ @@ -1071,6 +1141,8 @@ static struct file *ocxlflash_get_fd(void *ctx_cookie, if (fops) { PATCH_FOPS(poll); PATCH_FOPS(read); + PATCH_FOPS(release); + PATCH_FOPS(mmap); } else /* Use default ops */ fops = (struct file_operations *)&ocxl_afu_fops; -- 2.1.0