[PATCH v8 06/25] PCI/sysfs: Add static PCI resource attribute macros
From: Krzysztof Wilczyński <kwilczynski@kernel.org>
Date: 2026-06-19 08:52:27
Also in:
linux-alpha, linux-pci
Subsystem:
pci subsystem, the rest · Maintainers:
Bjorn Helgaas, Linus Torvalds
Add three macros for declaring static binary attributes for PCI resource files: - pci_dev_resource_io_attr(), for I/O BAR resources (read/write) - pci_dev_resource_uc_attr(), for memory BAR resources (mmap uncached) - pci_dev_resource_wc_attr(), for write-combine resources (mmap WC) Each macro only sets the callbacks its resource type needs. The I/O macro conditionally includes mmap support via __PCI_RESOURCE_IO_MMAP_ATTRS on architectures where arch_can_pci_mmap_io() is true at compile time (such as PowerPC, SPARC, and Xtensa). Tested-by: Shivaprasad G Bhat <redacted> Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org> --- drivers/pci/pci-sysfs.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index dac780597727..793d149fe157 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c@@ -1197,6 +1197,47 @@ static ssize_t pci_write_resource_io(struct file *filp, struct kobject *kobj, return pci_resource_io(filp, kobj, attr, buf, off, count, true); } +/* + * 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. + */ +#if arch_can_pci_mmap_io() +# define __PCI_RESOURCE_IO_MMAP_ATTRS \ + .f_mapping = iomem_get_mapping, \ + .llseek = pci_llseek_resource, \ + .mmap = pci_mmap_resource_uc, +#else +# define __PCI_RESOURCE_IO_MMAP_ATTRS +#endif + +#define pci_dev_resource_io_attr(_bar) \ +static const struct bin_attribute pci_dev_resource##_bar##_io_attr = { \ + .attr = { .name = "resource" __stringify(_bar), .mode = 0600 }, \ + .private = (void *)(unsigned long)(_bar), \ + .read = pci_read_resource_io, \ + .write = pci_write_resource_io, \ + __PCI_RESOURCE_IO_MMAP_ATTRS \ +} + +#define pci_dev_resource_uc_attr(_bar) \ +static const struct bin_attribute pci_dev_resource##_bar##_uc_attr = { \ + .attr = { .name = "resource" __stringify(_bar), .mode = 0600 }, \ + .private = (void *)(unsigned long)(_bar), \ + .f_mapping = iomem_get_mapping, \ + .llseek = pci_llseek_resource, \ + .mmap = pci_mmap_resource_uc, \ +} + +#define pci_dev_resource_wc_attr(_bar) \ +static const struct bin_attribute pci_dev_resource##_bar##_wc_attr = { \ + .attr = { .name = "resource" __stringify(_bar) "_wc", .mode = 0600 }, \ + .private = (void *)(unsigned long)(_bar), \ + .f_mapping = iomem_get_mapping, \ + .llseek = pci_llseek_resource, \ + .mmap = pci_mmap_resource_wc, \ +} + /** * pci_remove_resource_files - cleanup resource files * @pdev: dev to cleanup
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2.54.0