ARM: dma-mapping: split out vmregion code from dma coherent mapping code
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index b9590a7..c54f1ac 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -68,106 +68,16 @@
* These are the page tables (2MB each) covering uncached, DMA consistent allocations
*/
static pte_t *consistent_pte[NUM_CONSISTENT_PTES];
-static DEFINE_SPINLOCK(consistent_lock);
-/*
- * VM region handling support.
- *
- * This should become something generic, handling VM region allocations for
- * vmalloc and similar (ioremap, module space, etc).
- *
- * I envisage vmalloc()'s supporting vm_struct becoming:
- *
- * struct vm_struct {
- * struct vm_region region;
- * unsigned long flags;
- * struct page **pages;
- * unsigned int nr_pages;
- * unsigned long phys_addr;
- * };
- *
- * get_vm_area() would then call vm_region_alloc with an appropriate
- * struct vm_region head (eg):
- *
- * struct vm_region vmalloc_head = {
- * .vm_list = LIST_HEAD_INIT(vmalloc_head.vm_list),
- * .vm_start = VMALLOC_START,
- * .vm_end = VMALLOC_END,
- * };
- *
- * However, vmalloc_head.vm_start is variable (typically, it is dependent on
- * the amount of RAM found at boot time.) I would imagine that get_vm_area()
- * would have to initialise this each time prior to calling vm_region_alloc().
- */
-struct arm_vm_region {
- struct list_head vm_list;
- unsigned long vm_start;
- unsigned long vm_end;
- struct page *vm_pages;
- int vm_active;
-};
+#include "vmregion.h"
-static struct arm_vm_region consistent_head = {
+static struct arm_vmregion_head consistent_head = {
+ .vm_lock = __SPIN_LOCK_UNLOCKED(&consistent_head.vm_lock),
.vm_list = LIST_HEAD_INIT(consistent_head.vm_list),
.vm_start = CONSISTENT_BASE,
.vm_end = CONSISTENT_END,
};
-static struct arm_vm_region *
-arm_vm_region_alloc(struct arm_vm_region *head, size_t size, gfp_t gfp)
-{
- unsigned long addr = head->vm_start, end = head->vm_end - size;
- unsigned long flags;
- struct arm_vm_region *c, *new;
-
- new = kmalloc(sizeof(struct arm_vm_region), gfp);
- if (!new)
- goto out;
-
- spin_lock_irqsave(&consistent_lock, flags);
-
- list_for_each_entry(c, &head->vm_list, vm_list) {
- if ((addr + size) < addr)
- goto nospc;
- if ((addr + size) <= c->vm_start)
- goto found;
- addr = c->vm_end;
- if (addr > end)
- goto nospc;
- }
-
- found:
- /*
- * Insert this entry _before_ the one we found.
- */
- list_add_tail(&new->vm_list, &c->vm_list);
- new->vm_start = addr;
- new->vm_end = addr + size;
- new->vm_active = 1;
-
- spin_unlock_irqrestore(&consistent_lock, flags);
- return new;
-
- nospc:
- spin_unlock_irqrestore(&consistent_lock, flags);
- kfree(new);
- out:
- return NULL;
-}
-
-static struct arm_vm_region *arm_vm_region_find(struct arm_vm_region *head, unsigned long addr)
-{
- struct arm_vm_region *c;
-
- list_for_each_entry(c, &head->vm_list, vm_list) {
- if (c->vm_active && c->vm_start == addr)
- goto out;
- }
- c = NULL;
- out:
- return c;
-}
-
#ifdef CONFIG_HUGETLB_PAGE
#error ARM Coherent DMA allocator does not (yet) support huge TLB
#endif
@@ -177,7 +87,7 @@
pgprot_t prot)
{
struct page *page;
- struct arm_vm_region *c;
+ struct arm_vmregion *c;
unsigned long order;
u64 mask = get_coherent_dma_mask(dev);
u64 limit;
@@ -191,13 +101,9 @@
if (!mask)
goto no_page;
- /*
- * Sanity check the allocation size.
- */
size = PAGE_ALIGN(size);
limit = (mask + 1) & ~mask;
- if ((limit && size >= limit) ||
- size >= (CONSISTENT_END - CONSISTENT_BASE)) {
+ if (limit && size >= limit) {
printk(KERN_WARNING "coherent allocation too big "
"(requested %#x mask %#llx)\n", size, mask);
goto no_page;
@@ -226,7 +132,7 @@
/*
* Allocate a virtual address in the consistent mapping region.
*/
- c = arm_vm_region_alloc(&consistent_head, size,
+ c = arm_vmregion_alloc(&consistent_head, size,
gfp & ~(__GFP_DMA | __GFP_HIGHMEM));
if (c) {
pte_t *pte;
@@ -349,15 +255,12 @@
{
int ret = -ENXIO;
#ifdef CONFIG_MMU
- unsigned long flags, user_size, kern_size;
- struct arm_vm_region *c;
+ unsigned long user_size, kern_size;
+ struct arm_vmregion *c;
user_size = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
- spin_lock_irqsave(&consistent_lock, flags);
- c = arm_vm_region_find(&consistent_head, (unsigned long)cpu_addr);
- spin_unlock_irqrestore(&consistent_lock, flags);
-
+ c = arm_vmregion_find(&consistent_head, (unsigned long)cpu_addr);
if (c) {
unsigned long off = vma->vm_pgoff;
@@ -399,8 +302,8 @@
#ifdef CONFIG_MMU
void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle)
{
- struct arm_vm_region *c;
- unsigned long flags, addr;
+ struct arm_vmregion *c;
+ unsigned long addr;
pte_t *ptep;
int idx;
u32 off;
@@ -417,14 +320,10 @@
size = PAGE_ALIGN(size);
- spin_lock_irqsave(&consistent_lock, flags);
- c = arm_vm_region_find(&consistent_head, (unsigned long)cpu_addr);
+ c = arm_vmregion_find_remove(&consistent_head, (unsigned long)cpu_addr);
if (!c)
goto no_area;
- c->vm_active = 0;
- spin_unlock_irqrestore(&consistent_lock, flags);
-
if ((c->vm_end - c->vm_start) != size) {
printk(KERN_ERR "%s: freeing wrong coherent size (%ld != %d)\n",
__func__, c->vm_end - c->vm_start, size);
@@ -470,15 +369,10 @@
flush_tlb_kernel_range(c->vm_start, c->vm_end);
- spin_lock_irqsave(&consistent_lock, flags);
- list_del(&c->vm_list);
- spin_unlock_irqrestore(&consistent_lock, flags);
-
- kfree(c);
+ arm_vmregion_free(&consistent_head, c);
return;
no_area:
- spin_unlock_irqrestore(&consistent_lock, flags);
printk(KERN_ERR "%s: trying to free invalid coherent area: %p\n",
__func__, cpu_addr);
dump_stack();