drivers/misc/ocxl/sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 // Copyright 2017 IBM Corp.
   3 #include <linux/sysfs.h>
   4 #include "ocxl_internal.h"
   5
   6 static ssize_t global_mmio_size_show(struct device *device,
   7                                 struct device_attribute *attr,
   8                                 char *buf)
   9 {
  10         struct ocxl_afu *afu = to_ocxl_afu(device);
  11
  12         return scnprintf(buf, PAGE_SIZE, "%d\n",
  13                         afu->config.global_mmio_size);
  14 }
  15
  16 static ssize_t pp_mmio_size_show(struct device *device,
  17                                 struct device_attribute *attr,
  18                                 char *buf)
  19 {
  20         struct ocxl_afu *afu = to_ocxl_afu(device);
  21
  22         return scnprintf(buf, PAGE_SIZE, "%d\n",
  23                         afu->config.pp_mmio_stride);
  24 }
  25
  26 static ssize_t afu_version_show(struct device *device,
  27                                 struct device_attribute *attr,
  28                                 char *buf)
  29 {
  30         struct ocxl_afu *afu = to_ocxl_afu(device);
  31
  32         return scnprintf(buf, PAGE_SIZE, "%hhu:%hhu\n",
  33                         afu->config.version_major,
  34                         afu->config.version_minor);
  35 }
  36
  37 static ssize_t contexts_show(struct device *device,
  38                 struct device_attribute *attr,
  39                 char *buf)
  40 {
  41         struct ocxl_afu *afu = to_ocxl_afu(device);
  42
  43         return scnprintf(buf, PAGE_SIZE, "%d/%d\n",
  44                         afu->pasid_count, afu->pasid_max);
  45 }
  46
  47 static struct device_attribute afu_attrs[] = {
  48         __ATTR_RO(global_mmio_size),
  49         __ATTR_RO(pp_mmio_size),
  50         __ATTR_RO(afu_version),
  51         __ATTR_RO(contexts),
  52 };
  53
  54 static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
  55                                 struct bin_attribute *bin_attr, char *buf,
  56                                 loff_t off, size_t count)
  57 {
  58         struct ocxl_afu *afu = to_ocxl_afu(kobj_to_dev(kobj));
  59
  60         if (count == 0 || off < 0 ||
  61                 off >= afu->config.global_mmio_size)
  62                 return 0;
  63         memcpy_fromio(buf, afu->global_mmio_ptr + off, count);
  64         return count;
  65 }
  66
  67 static int global_mmio_fault(struct vm_fault *vmf)
  68 {
  69         struct vm_area_struct *vma = vmf->vma;
  70         struct ocxl_afu *afu = vma->vm_private_data;
  71         unsigned long offset;
  72
  73         if (vmf->pgoff >= (afu->config.global_mmio_size >> PAGE_SHIFT))
  74                 return VM_FAULT_SIGBUS;
  75
  76         offset = vmf->pgoff;
  77         offset += (afu->global_mmio_start >> PAGE_SHIFT);
  78         vm_insert_pfn(vma, vmf->address, offset);
  79         return VM_FAULT_NOPAGE;
  80 }
  81
  82 static const struct vm_operations_struct global_mmio_vmops = {
  83         .fault = global_mmio_fault,
  84 };
  85
  86 static int global_mmio_mmap(struct file *filp, struct kobject *kobj,
  87                         struct bin_attribute *bin_attr,
  88                         struct vm_area_struct *vma)
  89 {
  90         struct ocxl_afu *afu = to_ocxl_afu(kobj_to_dev(kobj));
  91
  92         if ((vma_pages(vma) + vma->vm_pgoff) >
  93                 (afu->config.global_mmio_size >> PAGE_SHIFT))
  94                 return -EINVAL;
  95
  96         vma->vm_flags |= VM_IO | VM_PFNMAP;
  97         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  98         vma->vm_ops = &global_mmio_vmops;
  99         vma->vm_private_data = afu;
 100         return 0;
 101 }
 102
 103 int ocxl_sysfs_add_afu(struct ocxl_afu *afu)
 104 {
 105         int i, rc;
 106
 107         for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
 108                 rc = device_create_file(&afu->dev, &afu_attrs[i]);
 109                 if (rc)
 110                         goto err;
 111         }
 112
 113         sysfs_attr_init(&afu->attr_global_mmio.attr);
 114         afu->attr_global_mmio.attr.name = "global_mmio_area";
 115         afu->attr_global_mmio.attr.mode = 0600;
 116         afu->attr_global_mmio.size = afu->config.global_mmio_size;
 117         afu->attr_global_mmio.read = global_mmio_read;
 118         afu->attr_global_mmio.mmap = global_mmio_mmap;
 119         rc = device_create_bin_file(&afu->dev, &afu->attr_global_mmio);
 120         if (rc) {
 121                 dev_err(&afu->dev,
 122                         "Unable to create global mmio attr for afu: %d\n",
 123                         rc);
 124                 goto err;
 125         }
 126
 127         return 0;
 128
 129 err:
 130         for (i--; i >= 0; i--)
 131                 device_remove_file(&afu->dev, &afu_attrs[i]);
 132         return rc;
 133 }
 134
 135 void ocxl_sysfs_remove_afu(struct ocxl_afu *afu)
 136 {
 137         int i;
 138
 139         for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
 140                 device_remove_file(&afu->dev, &afu_attrs[i]);
 141         device_remove_bin_file(&afu->dev, &afu->attr_global_mmio);
 142 }