From: Benjamin Herrenschmidt Date: Fri, 3 Oct 2008 09:49:32 +0000 (+1000) Subject: PCI: Add ability to mmap legacy_io on some platforms X-Git-Tag: v2.6.28-rc1~77^2~8 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=f19aeb1f3638b7bb4ca21eb361f004fac2bfe259;p=linux-2.6-omap-h63xx.git 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 --- diff --git a/arch/ia64/include/asm/pci.h b/arch/ia64/include/asm/pci.h index 0149097b736..ce342fb7424 100644 --- a/arch/ia64/include/asm/pci.h +++ b/arch/ia64/include/asm/pci.h @@ -95,16 +95,8 @@ extern int pci_mmap_page_range (struct pci_dev *dev, struct vm_area_struct *vma, enum pci_mmap_state mmap_state, int write_combine); #define HAVE_PCI_LEGACY extern int pci_mmap_legacy_page_range(struct pci_bus *bus, - struct vm_area_struct *vma); -extern ssize_t pci_read_legacy_io(struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t off, size_t count); -extern ssize_t pci_write_legacy_io(struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t off, size_t count); -extern int pci_mmap_legacy_mem(struct kobject *kobj, - struct bin_attribute *attr, - struct vm_area_struct *vma); + struct vm_area_struct *vma, + enum pci_mmap_state mmap_state); #define pci_get_legacy_mem platform_pci_get_legacy_mem #define pci_legacy_read platform_pci_legacy_read diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c index 7545037a862..211fcfd115f 100644 --- a/arch/ia64/pci/pci.c +++ b/arch/ia64/pci/pci.c @@ -614,12 +614,17 @@ char *ia64_pci_get_legacy_mem(struct pci_bus *bus) * vector to get the base address. */ int -pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma) +pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma, + enum pci_mmap_state mmap_state) { unsigned long size = vma->vm_end - vma->vm_start; pgprot_t prot; char *addr; + /* We only support mmap'ing of legacy memory space */ + if (mmap_state != pci_mmap_mem) + return -ENOSYS; + /* * Avoid attribute aliasing. See Documentation/ia64/aliasing.txt * for more details. 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 */ diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 39684c1415c..b205ab866a1 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -82,7 +82,13 @@ static inline int pci_proc_detach_bus(struct pci_bus *bus) { return 0; } /* Functions for PCI Hotplug drivers to use */ extern unsigned int pci_do_scan_bus(struct pci_bus *bus); +#ifdef HAVE_PCI_LEGACY +extern void pci_create_legacy_files(struct pci_bus *bus); extern void pci_remove_legacy_files(struct pci_bus *bus); +#else +static inline void pci_create_legacy_files(struct pci_bus *bus) { return; } +static inline void pci_remove_legacy_files(struct pci_bus *bus) { return; } +#endif /* Lock for read/write access to pci device and bus lists */ extern struct rw_semaphore pci_bus_sem; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index afb9f1c0bc2..aaaf0a1fed2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -42,72 +42,6 @@ int no_pci_devices(void) } EXPORT_SYMBOL(no_pci_devices); -#ifdef HAVE_PCI_LEGACY -/** - * 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. - */ -static 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; - 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 */ - } -} -#else /* !HAVE_PCI_LEGACY */ -static inline void pci_create_legacy_files(struct pci_bus *bus) { return; } -void pci_remove_legacy_files(struct pci_bus *bus) { return; } -#endif /* HAVE_PCI_LEGACY */ - /* * PCI Bus Class Devices */