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 inline struct ocxl_afu *to_afu(struct device *device)
   7 {
   8         struct ocxl_file_info *info = container_of(device, struct ocxl_file_info, dev);
   9
  10         return info->afu;
  11 }
  12
  13 static ssize_t global_mmio_size_show(struct device *device,
  14                                 struct device_attribute *attr,
  15                                 char *buf)
  16 {
  17         struct ocxl_afu *afu = to_afu(device);
  18
  19         return scnprintf(buf, PAGE_SIZE, "%d\n",
  20                         afu->config.global_mmio_size);
  21 }
  22
  23 static ssize_t pp_mmio_size_show(struct device *device,
  24                                 struct device_attribute *attr,
  25                                 char *buf)
  26 {
  27         struct ocxl_afu *afu = to_afu(device);
  28
  29         return scnprintf(buf, PAGE_SIZE, "%d\n",
  30                         afu->config.pp_mmio_stride);
  31 }
  32
  33 static ssize_t afu_version_show(struct device *device,
  34                                 struct device_attribute *attr,
  35                                 char *buf)
  36 {
  37         struct ocxl_afu *afu = to_afu(device);
  38
  39         return scnprintf(buf, PAGE_SIZE, "%hhu:%hhu\n",
  40                         afu->config.version_major,
  41                         afu->config.version_minor);
  42 }
  43
  44 static ssize_t contexts_show(struct device *device,
  45                 struct device_attribute *attr,
  46                 char *buf)
  47 {
  48         struct ocxl_afu *afu = to_afu(device);
  49
  50         return scnprintf(buf, PAGE_SIZE, "%d/%d\n",
  51                         afu->pasid_count, afu->pasid_max);
  52 }
  53
  54 static ssize_t reload_on_reset_show(struct device *device,
  55                                     struct device_attribute *attr,
  56                                     char *buf)
  57 {
  58         struct ocxl_afu *afu = to_afu(device);
  59         struct ocxl_fn *fn = afu->fn;
  60         struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
  61         int val;
  62
  63         if (ocxl_config_get_reset_reload(pci_dev, &val))
  64                 return scnprintf(buf, PAGE_SIZE, "unavailable\n");
  65
  66         return scnprintf(buf, PAGE_SIZE, "%d\n", val);
  67 }
  68
  69 static ssize_t reload_on_reset_store(struct device *device,
  70                                      struct device_attribute *attr,
  71                                      const char *buf, size_t count)
  72 {
  73         struct ocxl_afu *afu = to_afu(device);
  74         struct ocxl_fn *fn = afu->fn;
  75         struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
  76         int rc, val;
  77
  78         rc = kstrtoint(buf, 0, &val);
  79         if (rc || (val != 0 && val != 1))
  80                 return -EINVAL;
  81
  82         if (ocxl_config_set_reset_reload(pci_dev, val))
  83                 return -ENODEV;
  84
  85         return count;
  86 }
  87
  88 static struct device_attribute afu_attrs[] = {
  89         __ATTR_RO(global_mmio_size),
  90         __ATTR_RO(pp_mmio_size),
  91         __ATTR_RO(afu_version),
  92         __ATTR_RO(contexts),
  93         __ATTR_RW(reload_on_reset),
  94 };
  95
  96 static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
  97                                 struct bin_attribute *bin_attr, char *buf,
  98                                 loff_t off, size_t count)
  99 {
 100         struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
 101
 102         if (count == 0 || off < 0 ||
 103                 off >= afu->config.global_mmio_size)
 104                 return 0;
 105         memcpy_fromio(buf, afu->global_mmio_ptr + off, count);
 106         return count;
 107 }
 108
 109 static vm_fault_t global_mmio_fault(struct vm_fault *vmf)
 110 {
 111         struct vm_area_struct *vma = vmf->vma;
 112         struct ocxl_afu *afu = vma->vm_private_data;
 113         unsigned long offset;
 114
 115         if (vmf->pgoff >= (afu->config.global_mmio_size >> PAGE_SHIFT))
 116                 return VM_FAULT_SIGBUS;
 117
 118         offset = vmf->pgoff;
 119         offset += (afu->global_mmio_start >> PAGE_SHIFT);
 120         return vmf_insert_pfn(vma, vmf->address, offset);
 121 }
 122
 123 static const struct vm_operations_struct global_mmio_vmops = {
 124         .fault = global_mmio_fault,
 125 };
 126
 127 static int global_mmio_mmap(struct file *filp, struct kobject *kobj,
 128                         const struct bin_attribute *bin_attr,
 129                         struct vm_area_struct *vma)
 130 {
 131         struct ocxl_afu *afu = to_afu(kobj_to_dev(kobj));
 132
 133         if ((vma_pages(vma) + vma->vm_pgoff) >
 134                 (afu->config.global_mmio_size >> PAGE_SHIFT))
 135                 return -EINVAL;
 136
 137         vm_flags_set(vma, VM_IO | VM_PFNMAP);
 138         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 139         vma->vm_ops = &global_mmio_vmops;
 140         vma->vm_private_data = afu;
 141         return 0;
 142 }
 143
 144 int ocxl_sysfs_register_afu(struct ocxl_file_info *info)
 145 {
 146         int i, rc;
 147
 148         for (i = 0; i < ARRAY_SIZE(afu_attrs); i++) {
 149                 rc = device_create_file(&info->dev, &afu_attrs[i]);
 150                 if (rc)
 151                         goto err;
 152         }
 153
 154         sysfs_attr_init(&info->attr_global_mmio.attr);
 155         info->attr_global_mmio.attr.name = "global_mmio_area";
 156         info->attr_global_mmio.attr.mode = 0600;
 157         info->attr_global_mmio.size = info->afu->config.global_mmio_size;
 158         info->attr_global_mmio.read = global_mmio_read;
 159         info->attr_global_mmio.mmap = global_mmio_mmap;
 160         rc = device_create_bin_file(&info->dev, &info->attr_global_mmio);
 161         if (rc) {
 162                 dev_err(&info->dev, "Unable to create global mmio attr for afu: %d\n", rc);
 163                 goto err;
 164         }
 165
 166         return 0;
 167
 168 err:
 169         for (i--; i >= 0; i--)
 170                 device_remove_file(&info->dev, &afu_attrs[i]);
 171
 172         return rc;
 173 }
 174
 175 void ocxl_sysfs_unregister_afu(struct ocxl_file_info *info)
 176 {
 177         int i;
 178
 179         /*
 180          * device_remove_bin_file is safe to call if the file is not added as
 181          * the files are removed by name, and early exit if not found
 182          */
 183         for (i = 0; i < ARRAY_SIZE(afu_attrs); i++)
 184                 device_remove_file(&info->dev, &afu_attrs[i]);
 185         device_remove_bin_file(&info->dev, &info->attr_global_mmio);
 186 }