diff options
Diffstat (limited to 'drivers/pci/pci-sysfs.c')
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 8e6d1031510b..2321fdfefd7d 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -831,6 +831,19 @@ static const struct attribute_group pci_dev_config_attr_group = { .is_bin_visible = pci_dev_config_attr_is_visible, }; +/* + * llseek operation for mmappable PCI resources. + * May be left unused if the arch doesn't provide them. + */ +static __maybe_unused loff_t +pci_llseek_resource(struct file *filep, + struct kobject *kobj __always_unused, + struct bin_attribute *attr, + loff_t offset, int whence) +{ + return fixed_size_llseek(filep, offset, whence, attr->size); +} + #ifdef HAVE_PCI_LEGACY /** * pci_read_legacy_io - read byte(s) from legacy I/O port space @@ -963,6 +976,8 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_io->attr.mode = 0600; b->legacy_io->read = pci_read_legacy_io; b->legacy_io->write = pci_write_legacy_io; + /* See pci_create_attr() for motivation */ + b->legacy_io->llseek = pci_llseek_resource; b->legacy_io->mmap = pci_mmap_legacy_io; b->legacy_io->f_mapping = iomem_get_mapping; pci_adjust_legacy_attr(b, pci_mmap_io); @@ -977,6 +992,8 @@ void pci_create_legacy_files(struct pci_bus *b) b->legacy_mem->size = 1024*1024; b->legacy_mem->attr.mode = 0600; b->legacy_mem->mmap = pci_mmap_legacy_mem; + /* See pci_create_attr() for motivation */ + b->legacy_mem->llseek = pci_llseek_resource; b->legacy_mem->f_mapping = iomem_get_mapping; pci_adjust_legacy_attr(b, pci_mmap_mem); error = device_create_bin_file(&b->dev, b->legacy_mem); @@ -1195,8 +1212,15 @@ static int pci_create_attr(struct pci_dev *pdev, int num, int write_combine) res_attr->mmap = pci_mmap_resource_uc; } } - if (res_attr->mmap) + if (res_attr->mmap) { res_attr->f_mapping = iomem_get_mapping; + /* + * generic_file_llseek() consults f_mapping->host to determine + * the file size. As iomem_inode knows nothing about the + * attribute, it's not going to work, so override it as well. + */ + res_attr->llseek = pci_llseek_resource; + } res_attr->attr.name = res_attr_name; res_attr->attr.mode = 0600; res_attr->size = pci_resource_len(pdev, num); |