From f19aeb1f3638b7bb4ca21eb361f004fac2bfe259 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 3 Oct 2008 19:49:32 +1000 Subject: PCI: Add ability to mmap legacy_io on some platforms This adds the ability to mmap legacy IO space to the legacy_io files in sysfs on platforms that support it. This will allow to clean up X to use this instead of /dev/mem for legacy IO accesses such as those performed by Int10. While at it I moved pci_create/remove_legacy_files() to pci-sysfs.c where I think they belong, thus making more things statis in there and cleaned up some spurrious prototypes in the ia64 pci.h file Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Jesse Barnes --- drivers/pci/pci-sysfs.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 88 insertions(+), 5 deletions(-) (limited to 'drivers/pci/pci-sysfs.c') diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 2cad6da2e4a..110022d7868 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -423,7 +423,7 @@ pci_write_vpd(struct kobject *kobj, struct bin_attribute *bin_attr, * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific * callback routine (pci_legacy_read). */ -ssize_t +static ssize_t pci_read_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { @@ -448,7 +448,7 @@ pci_read_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr, * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific * callback routine (pci_legacy_write). */ -ssize_t +static ssize_t pci_write_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count) { @@ -468,11 +468,11 @@ pci_write_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr, * @attr: struct bin_attribute for this file * @vma: struct vm_area_struct passed to mmap * - * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap + * Uses an arch specific callback, pci_mmap_legacy_mem_page_range, to mmap * legacy memory space (first meg of bus space) into application virtual * memory space. */ -int +static int pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr, struct vm_area_struct *vma) { @@ -480,7 +480,90 @@ pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr, struct device, kobj)); - return pci_mmap_legacy_page_range(bus, vma); + return pci_mmap_legacy_page_range(bus, vma, pci_mmap_mem); +} + +/** + * pci_mmap_legacy_io - map legacy PCI IO into user memory space + * @kobj: kobject corresponding to device to be mapped + * @attr: struct bin_attribute for this file + * @vma: struct vm_area_struct passed to mmap + * + * Uses an arch specific callback, pci_mmap_legacy_io_page_range, to mmap + * legacy IO space (first meg of bus space) into application virtual + * memory space. Returns -ENOSYS if the operation isn't supported + */ +static int +pci_mmap_legacy_io(struct kobject *kobj, struct bin_attribute *attr, + struct vm_area_struct *vma) +{ + struct pci_bus *bus = to_pci_bus(container_of(kobj, + struct device, + kobj)); + + return pci_mmap_legacy_page_range(bus, vma, pci_mmap_io); +} + +/** + * pci_create_legacy_files - create legacy I/O port and memory files + * @b: bus to create files under + * + * Some platforms allow access to legacy I/O port and ISA memory space on + * a per-bus basis. This routine creates the files and ties them into + * their associated read, write and mmap files from pci-sysfs.c + * + * On error unwind, but don't propogate the error to the caller + * as it is ok to set up the PCI bus without these files. + */ +void pci_create_legacy_files(struct pci_bus *b) +{ + int error; + + b->legacy_io = kzalloc(sizeof(struct bin_attribute) * 2, + GFP_ATOMIC); + if (!b->legacy_io) + goto kzalloc_err; + + b->legacy_io->attr.name = "legacy_io"; + b->legacy_io->size = 0xffff; + b->legacy_io->attr.mode = S_IRUSR | S_IWUSR; + b->legacy_io->read = pci_read_legacy_io; + b->legacy_io->write = pci_write_legacy_io; + b->legacy_io->mmap = pci_mmap_legacy_io; + error = device_create_bin_file(&b->dev, b->legacy_io); + if (error) + goto legacy_io_err; + + /* Allocated above after the legacy_io struct */ + b->legacy_mem = b->legacy_io + 1; + b->legacy_mem->attr.name = "legacy_mem"; + b->legacy_mem->size = 1024*1024; + b->legacy_mem->attr.mode = S_IRUSR | S_IWUSR; + b->legacy_mem->mmap = pci_mmap_legacy_mem; + error = device_create_bin_file(&b->dev, b->legacy_mem); + if (error) + goto legacy_mem_err; + + return; + +legacy_mem_err: + device_remove_bin_file(&b->dev, b->legacy_io); +legacy_io_err: + kfree(b->legacy_io); + b->legacy_io = NULL; +kzalloc_err: + printk(KERN_WARNING "pci: warning: could not create legacy I/O port " + "and ISA memory resources to sysfs\n"); + return; +} + +void pci_remove_legacy_files(struct pci_bus *b) +{ + if (b->legacy_io) { + device_remove_bin_file(&b->dev, b->legacy_io); + device_remove_bin_file(&b->dev, b->legacy_mem); + kfree(b->legacy_io); /* both are allocated here */ + } } #endif /* HAVE_PCI_LEGACY */ -- cgit v1.2.3