kernel-ark/drivers/ieee1394/dma.c
Ben Collins 1934b8b656 [PATCH] Sync up ieee-1394
Lots of this patch is trivial code cleanups (static vars were being
intialized to 0, etc).

There's also some fixes for ISO transmits (max buffer handling).
Aswell, we have a few fixes to disable IRM capabilites correctly.  We've
also disabled, by default some generally unused EXPORT symbols for the
sake of cleanliness in the kernel.  However, instead of removing them
completely, we felt it necessary to have a config option that allowed
them to be enabled for the many projects outside of the main kernel tree
that use our API for driver development.

The primary reason for this patch is to revert a MODE6->MODE10 RBC
conversion patch from the SCSI maintainers.  The new conversions handled
directly in the scsi layer do not seem to work for SBP2.  This patch
reverts to our old working code so that users can enjoy using Firewire
disks and dvd drives again.

We are working with the SCSI maintainers to resolve this issue outside
of the main kernel tree.  We'll merge the patch once the SCSI layer's
handling of the MODE10 conversion is working for us.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-10 12:23:23 -07:00

261 lines
5.7 KiB
C

/*
* DMA region bookkeeping routines
*
* Copyright (C) 2002 Maas Digital LLC
*
* This code is licensed under the GPL. See the file COPYING in the root
* directory of the kernel sources for details.
*/
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include "dma.h"
/* dma_prog_region */
void dma_prog_region_init(struct dma_prog_region *prog)
{
prog->kvirt = NULL;
prog->dev = NULL;
prog->n_pages = 0;
prog->bus_addr = 0;
}
int dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes, struct pci_dev *dev)
{
/* round up to page size */
n_bytes = PAGE_ALIGN(n_bytes);
prog->n_pages = n_bytes >> PAGE_SHIFT;
prog->kvirt = pci_alloc_consistent(dev, n_bytes, &prog->bus_addr);
if (!prog->kvirt) {
printk(KERN_ERR "dma_prog_region_alloc: pci_alloc_consistent() failed\n");
dma_prog_region_free(prog);
return -ENOMEM;
}
prog->dev = dev;
return 0;
}
void dma_prog_region_free(struct dma_prog_region *prog)
{
if (prog->kvirt) {
pci_free_consistent(prog->dev, prog->n_pages << PAGE_SHIFT, prog->kvirt, prog->bus_addr);
}
prog->kvirt = NULL;
prog->dev = NULL;
prog->n_pages = 0;
prog->bus_addr = 0;
}
/* dma_region */
void dma_region_init(struct dma_region *dma)
{
dma->kvirt = NULL;
dma->dev = NULL;
dma->n_pages = 0;
dma->n_dma_pages = 0;
dma->sglist = NULL;
}
int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes, struct pci_dev *dev, int direction)
{
unsigned int i;
/* round up to page size */
n_bytes = PAGE_ALIGN(n_bytes);
dma->n_pages = n_bytes >> PAGE_SHIFT;
dma->kvirt = vmalloc_32(n_bytes);
if (!dma->kvirt) {
printk(KERN_ERR "dma_region_alloc: vmalloc_32() failed\n");
goto err;
}
/* Clear the ram out, no junk to the user */
memset(dma->kvirt, 0, n_bytes);
/* allocate scatter/gather list */
dma->sglist = vmalloc(dma->n_pages * sizeof(*dma->sglist));
if (!dma->sglist) {
printk(KERN_ERR "dma_region_alloc: vmalloc(sglist) failed\n");
goto err;
}
/* just to be safe - this will become unnecessary once sglist->address goes away */
memset(dma->sglist, 0, dma->n_pages * sizeof(*dma->sglist));
/* fill scatter/gather list with pages */
for (i = 0; i < dma->n_pages; i++) {
unsigned long va = (unsigned long) dma->kvirt + (i << PAGE_SHIFT);
dma->sglist[i].page = vmalloc_to_page((void *)va);
dma->sglist[i].length = PAGE_SIZE;
}
/* map sglist to the IOMMU */
dma->n_dma_pages = pci_map_sg(dev, dma->sglist, dma->n_pages, direction);
if (dma->n_dma_pages == 0) {
printk(KERN_ERR "dma_region_alloc: pci_map_sg() failed\n");
goto err;
}
dma->dev = dev;
dma->direction = direction;
return 0;
err:
dma_region_free(dma);
return -ENOMEM;
}
void dma_region_free(struct dma_region *dma)
{
if (dma->n_dma_pages) {
pci_unmap_sg(dma->dev, dma->sglist, dma->n_pages, dma->direction);
dma->n_dma_pages = 0;
dma->dev = NULL;
}
vfree(dma->sglist);
dma->sglist = NULL;
vfree(dma->kvirt);
dma->kvirt = NULL;
dma->n_pages = 0;
}
/* find the scatterlist index and remaining offset corresponding to a
given offset from the beginning of the buffer */
static inline int dma_region_find(struct dma_region *dma, unsigned long offset, unsigned long *rem)
{
int i;
unsigned long off = offset;
for (i = 0; i < dma->n_dma_pages; i++) {
if (off < sg_dma_len(&dma->sglist[i])) {
*rem = off;
break;
}
off -= sg_dma_len(&dma->sglist[i]);
}
BUG_ON(i >= dma->n_dma_pages);
return i;
}
dma_addr_t dma_region_offset_to_bus(struct dma_region *dma, unsigned long offset)
{
unsigned long rem = 0;
struct scatterlist *sg = &dma->sglist[dma_region_find(dma, offset, &rem)];
return sg_dma_address(sg) + rem;
}
void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset, unsigned long len)
{
int first, last;
unsigned long rem;
if (!len)
len = 1;
first = dma_region_find(dma, offset, &rem);
last = dma_region_find(dma, offset + len - 1, &rem);
pci_dma_sync_sg_for_cpu(dma->dev, &dma->sglist[first], last - first + 1, dma->direction);
}
void dma_region_sync_for_device(struct dma_region *dma, unsigned long offset, unsigned long len)
{
int first, last;
unsigned long rem;
if (!len)
len = 1;
first = dma_region_find(dma, offset, &rem);
last = dma_region_find(dma, offset + len - 1, &rem);
pci_dma_sync_sg_for_device(dma->dev, &dma->sglist[first], last - first + 1, dma->direction);
}
#ifdef CONFIG_MMU
/* nopage() handler for mmap access */
static struct page*
dma_region_pagefault(struct vm_area_struct *area, unsigned long address, int *type)
{
unsigned long offset;
unsigned long kernel_virt_addr;
struct page *ret = NOPAGE_SIGBUS;
struct dma_region *dma = (struct dma_region*) area->vm_private_data;
if (!dma->kvirt)
goto out;
if ( (address < (unsigned long) area->vm_start) ||
(address > (unsigned long) area->vm_start + (dma->n_pages << PAGE_SHIFT)) )
goto out;
if (type)
*type = VM_FAULT_MINOR;
offset = address - area->vm_start;
kernel_virt_addr = (unsigned long) dma->kvirt + offset;
ret = vmalloc_to_page((void*) kernel_virt_addr);
get_page(ret);
out:
return ret;
}
static struct vm_operations_struct dma_region_vm_ops = {
.nopage = dma_region_pagefault,
};
int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma)
{
unsigned long size;
if (!dma->kvirt)
return -EINVAL;
/* must be page-aligned */
if (vma->vm_pgoff != 0)
return -EINVAL;
/* check the length */
size = vma->vm_end - vma->vm_start;
if (size > (dma->n_pages << PAGE_SHIFT))
return -EINVAL;
vma->vm_ops = &dma_region_vm_ops;
vma->vm_private_data = dma;
vma->vm_file = file;
vma->vm_flags |= VM_RESERVED;
return 0;
}
#else /* CONFIG_MMU */
int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma)
{
return -EINVAL;
}
#endif /* CONFIG_MMU */