* directory of the kernel sources for details.
*/
+#include <linux/mm.h>
#include <linux/module.h>
-#include <linux/vmalloc.h>
+#include <linux/pci.h>
#include <linux/slab.h>
-#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/scatterlist.h>
+
#include "dma.h"
/* dma_prog_region */
prog->bus_addr = 0;
}
-int dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes, struct pci_dev *dev)
+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->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");
+ printk(KERN_ERR
+ "dma_prog_region_alloc: pci_alloc_consistent() failed\n");
dma_prog_region_free(prog);
return -ENOMEM;
}
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);
+ pci_free_consistent(prog->dev, prog->n_pages << PAGE_SHIFT,
+ prog->kvirt, prog->bus_addr);
}
prog->kvirt = NULL;
/* dma_region */
+/**
+ * dma_region_init - clear out all fields but do not allocate anything
+ */
void dma_region_init(struct dma_region *dma)
{
dma->kvirt = NULL;
dma->sglist = NULL;
}
-int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes, struct pci_dev *dev, int direction)
+/**
+ * dma_region_alloc - allocate the buffer and map it to the IOMMU
+ */
+int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes,
+ struct pci_dev *dev, int direction)
{
unsigned int i;
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));
+ sg_init_table(dma->sglist, dma->n_pages);
/* fill scatter/gather list with pages */
for (i = 0; i < dma->n_pages; i++) {
- unsigned long va = (unsigned long) dma->kvirt + (i << PAGE_SHIFT);
+ 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;
+ sg_set_page(&dma->sglist[i], vmalloc_to_page((void *)va),
+ PAGE_SIZE, 0);
}
/* map sglist to the IOMMU */
- dma->n_dma_pages = pci_map_sg(dev, dma->sglist, dma->n_pages, direction);
+ 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");
return 0;
-err:
+ err:
dma_region_free(dma);
return -ENOMEM;
}
+/**
+ * dma_region_free - unmap and free the buffer
+ */
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);
+ pci_unmap_sg(dma->dev, dma->sglist, dma->n_pages,
+ dma->direction);
dma->n_dma_pages = 0;
dma->dev = NULL;
}
/* 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)
+static inline int dma_region_find(struct dma_region *dma, unsigned long offset,
+ unsigned int start, unsigned long *rem)
{
int i;
unsigned long off = offset;
- for (i = 0; i < dma->n_dma_pages; i++) {
+ for (i = start; i < dma->n_dma_pages; i++) {
if (off < sg_dma_len(&dma->sglist[i])) {
*rem = off;
break;
return i;
}
-dma_addr_t dma_region_offset_to_bus(struct dma_region *dma, unsigned long offset)
+/**
+ * dma_region_offset_to_bus - get bus address of an offset within a DMA region
+ *
+ * Returns the DMA bus address of the byte with the given @offset relative to
+ * the beginning of the @dma.
+ */
+dma_addr_t dma_region_offset_to_bus(struct dma_region * dma,
+ unsigned long offset)
{
- unsigned long rem;
+ unsigned long rem = 0;
- struct scatterlist *sg = &dma->sglist[dma_region_find(dma, offset, &rem)];
+ struct scatterlist *sg =
+ &dma->sglist[dma_region_find(dma, offset, 0, &rem)];
return sg_dma_address(sg) + rem;
}
-void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset, unsigned long len)
+/**
+ * dma_region_sync_for_cpu - sync the CPU's view of the buffer
+ */
+void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset,
+ unsigned long len)
{
int first, last;
- unsigned long rem;
+ unsigned long rem = 0;
if (!len)
len = 1;
- first = dma_region_find(dma, offset, &rem);
- last = dma_region_find(dma, offset + len - 1, &rem);
+ first = dma_region_find(dma, offset, 0, &rem);
+ last = dma_region_find(dma, rem + len - 1, first, &rem);
- pci_dma_sync_sg_for_cpu(dma->dev, &dma->sglist[first], last - first + 1, dma->direction);
+ 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)
+/**
+ * dma_region_sync_for_device - sync the IO bus' view of the buffer
+ */
+void dma_region_sync_for_device(struct dma_region *dma, unsigned long offset,
+ unsigned long len)
{
int first, last;
- unsigned long rem;
+ unsigned long rem = 0;
if (!len)
len = 1;
- first = dma_region_find(dma, offset, &rem);
- last = dma_region_find(dma, offset + len - 1, &rem);
+ first = dma_region_find(dma, offset, 0, &rem);
+ last = dma_region_find(dma, rem + len - 1, first, &rem);
- pci_dma_sync_sg_for_device(dma->dev, &dma->sglist[first], last - first + 1, dma->direction);
+ 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)
+static int dma_region_pagefault(struct vm_area_struct *vma,
+ struct vm_fault *vmf)
{
- unsigned long offset;
- unsigned long kernel_virt_addr;
- struct page *ret = NOPAGE_SIGBUS;
-
- struct dma_region *dma = (struct dma_region*) area->vm_private_data;
+ struct dma_region *dma = (struct dma_region *)vma->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;
+ return VM_FAULT_SIGBUS;
+
+ if (vmf->pgoff >= dma->n_pages)
+ return VM_FAULT_SIGBUS;
+
+ vmf->page = vmalloc_to_page(dma->kvirt + (vmf->pgoff << PAGE_SHIFT));
+ get_page(vmf->page);
+ return 0;
}
static struct vm_operations_struct dma_region_vm_ops = {
- .nopage = dma_region_pagefault,
+ .fault = dma_region_pagefault,
};
-int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma)
+/**
+ * dma_region_mmap - map the buffer into a user space process
+ */
+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 */
+ /* must be page-aligned (XXX: comment is wrong, we could allow pgoff) */
if (vma->vm_pgoff != 0)
return -EINVAL;
vma->vm_ops = &dma_region_vm_ops;
vma->vm_private_data = dma;
vma->vm_file = file;
- vma->vm_flags |= VM_RESERVED;
+ vma->vm_flags |= VM_RESERVED | VM_ALWAYSDUMP;
return 0;
}
-#else /* CONFIG_MMU */
+#else /* CONFIG_MMU */
-int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma)
+int dma_region_mmap(struct dma_region *dma, struct file *file,
+ struct vm_area_struct *vma)
{
return -EINVAL;
}
-#endif /* CONFIG_MMU */
+#endif /* CONFIG_MMU */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff