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Commit f19aeb1f authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Jesse Barnes
Browse files

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: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent f393d9b1

arch/ia64/include/asm/pci.h

+2 −10
Original line number Diff line number Diff line
@@ -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

arch/ia64/pci/pci.c

+6 −1
Original line number Diff line number Diff line
@@ -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.

drivers/pci/pci-sysfs.c

+88 −5
Original line number Diff line number Diff line
@@ -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 */

drivers/pci/pci.h

+6 −0
Original line number Diff line number Diff line
@@ -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;

drivers/pci/probe.c

+0 −66
Original line number Diff line number Diff line
@@ -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

 */