microblaze: Fix consistent code

This patch fix consistent code which had problems with consistent_free
function.
I am not sure if we need to call flush_tlb_all after it but it keeps
tlbs synced.
I added noMMU and MMU version together.

Uncached shadow feature is not tested.

Signed-off-by: Michal Simek <monstr@monstr.eu>

diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
index 16a117ed26067cfbea0a3ff465e860611f95aecb..ca2d92871545821affe833848788e976b8c2f09a 100644 (file)
--- a/arch/microblaze/include/asm/pgtable.h
+++ b/arch/microblaze/include/asm/pgtable.h
@@ -568,7 +568,7 @@ void __init *early_get_page(void);
 extern unsigned long ioremap_bot, ioremap_base;
 
 void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle);
-void consistent_free(void *vaddr);
+void consistent_free(size_t size, void *vaddr);
 void consistent_sync(void *vaddr, size_t size, int direction);
 void consistent_sync_page(struct page *page, unsigned long offset,
        size_t size, int direction);

diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c
index ce72dd4967cfe2085ada81f60e54f3c55ee4c2e7..9dcd90b5df55bdf08cd869fba62f56219797c555 100644 (file)
--- a/arch/microblaze/kernel/dma.c
+++ b/arch/microblaze/kernel/dma.c
@@ -74,7 +74,7 @@ static void dma_direct_free_coherent(struct device *dev, size_t size,
                              void *vaddr, dma_addr_t dma_handle)
 {
 #ifdef NOT_COHERENT_CACHE
-       consistent_free(vaddr);
+       consistent_free(size, vaddr);
 #else
        free_pages((unsigned long)vaddr, get_order(size));
 #endif

diff --git a/arch/microblaze/mm/consistent.c b/arch/microblaze/mm/consistent.c
index f956e24fe49ccc11927d4648a62952b1f3036e20..713431caf592d8332887259fded42d5872d8318e 100644 (file)
--- a/arch/microblaze/mm/consistent.c
+++ b/arch/microblaze/mm/consistent.c
@@ -42,11 +42,12 @@
 #include <linux/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/cpuinfo.h>
+#include <asm/tlbflush.h>
 
 #ifndef CONFIG_MMU
-
 /* I have to use dcache values because I can't relate on ram size */
-#define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
+# define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
+#endif
 
 /*
  * Consistent memory allocators. Used for DMA devices that want to
@@ -60,71 +61,16 @@
  */
 void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle)
 {
-       struct page *page, *end, *free;
-       unsigned long order;
-       void *ret, *virt;
-
-       if (in_interrupt())
-               BUG();
-
-       size = PAGE_ALIGN(size);
-       order = get_order(size);
-
-       page = alloc_pages(gfp, order);
-       if (!page)
-               goto no_page;
-
-       /* We could do with a page_to_phys and page_to_bus here. */
-       virt = page_address(page);
-       ret = ioremap(virt_to_phys(virt), size);
-       if (!ret)
-               goto no_remap;
-
-       /*
-        * Here's the magic!  Note if the uncached shadow is not implemented,
-        * it's up to the calling code to also test that condition and make
-        * other arranegments, such as manually flushing the cache and so on.
-        */
-#ifdef CONFIG_XILINX_UNCACHED_SHADOW
-       ret = (void *)((unsigned) ret | UNCACHED_SHADOW_MASK);
-#endif
-       /* dma_handle is same as physical (shadowed) address */
-       *dma_handle = (dma_addr_t)ret;
-
-       /*
-        * free wasted pages.  We skip the first page since we know
-        * that it will have count = 1 and won't require freeing.
-        * We also mark the pages in use as reserved so that
-        * remap_page_range works.
-        */
-       page = virt_to_page(virt);
-       free = page + (size >> PAGE_SHIFT);
-       end  = page + (1 << order);
-
-       for (; page < end; page++) {
-               init_page_count(page);
-               if (page >= free)
-                       __free_page(page);
-               else
-                       SetPageReserved(page);
-       }
-
-       return ret;
-no_remap:
-       __free_pages(page, order);
-no_page:
-       return NULL;
-}
-
-#else
+       unsigned long order, vaddr;
+       void *ret;
+       unsigned int i, err = 0;
+       struct page *page, *end;
 
-void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle)
-{
-       int order, err, i;
-       unsigned long page, va, flags;
+#ifdef CONFIG_MMU
        phys_addr_t pa;
        struct vm_struct *area;
-       void     *ret;
+       unsigned long va;
+#endif
 
        if (in_interrupt())
                BUG();
@@ -133,71 +79,133 @@ void *consistent_alloc(int gfp, size_t size, dma_addr_t *dma_handle)
        size = PAGE_ALIGN(size);
        order = get_order(size);
 
-       page = __get_free_pages(gfp, order);
-       if (!page) {
-               BUG();
+       vaddr = __get_free_pages(gfp, order);
+       if (!vaddr)
                return NULL;
-       }
 
        /*
         * we need to ensure that there are no cachelines in use,
         * or worse dirty in this area.
         */
-       flush_dcache_range(virt_to_phys(page), virt_to_phys(page) + size);
+       flush_dcache_range(virt_to_phys((void *)vaddr),
+                                       virt_to_phys((void *)vaddr) + size);
 
+#ifndef CONFIG_MMU
+       ret = (void *)vaddr;
+       /*
+        * Here's the magic!  Note if the uncached shadow is not implemented,
+        * it's up to the calling code to also test that condition and make
+        * other arranegments, such as manually flushing the cache and so on.
+        */
+# ifdef CONFIG_XILINX_UNCACHED_SHADOW
+       ret = (void *)((unsigned) ret | UNCACHED_SHADOW_MASK);
+# endif
+       if ((unsigned int)ret > cpuinfo.dcache_base &&
+                               (unsigned int)ret < cpuinfo.dcache_high)
+               printk(KERN_WARNING
+                       "ERROR: Your cache coherent area is CACHED!!!\n");
+
+       /* dma_handle is same as physical (shadowed) address */
+       *dma_handle = (dma_addr_t)ret;
+#else
        /* Allocate some common virtual space to map the new pages. */
        area = get_vm_area(size, VM_ALLOC);
-       if (area == NULL) {
-               free_pages(page, order);
+       if (!area) {
+               free_pages(vaddr, order);
                return NULL;
        }
        va = (unsigned long) area->addr;
        ret = (void *)va;
 
        /* This gives us the real physical address of the first page. */
-       *dma_handle = pa = virt_to_bus((void *)page);
-
-       /* MS: This is the whole magic - use cache inhibit pages */
-       flags = _PAGE_KERNEL | _PAGE_NO_CACHE;
+       *dma_handle = pa = virt_to_bus((void *)vaddr);
+#endif
 
        /*
-        * Set refcount=1 on all pages in an order>0
-        * allocation so that vfree() will actually
-        * free all pages that were allocated.
+        * free wasted pages.  We skip the first page since we know
+        * that it will have count = 1 and won't require freeing.
+        * We also mark the pages in use as reserved so that
+        * remap_page_range works.
         */
-       if (order > 0) {
-               struct page *rpage = virt_to_page(page);
-               for (i = 1; i < (1 << order); i++)
-                       init_page_count(rpage+i);
+       page = virt_to_page(vaddr);
+       end = page + (1 << order);
+
+       split_page(page, order);
+
+       for (i = 0; i < size && err == 0; i += PAGE_SIZE) {
+#ifdef CONFIG_MMU
+               /* MS: This is the whole magic - use cache inhibit pages */
+               err = map_page(va + i, pa + i, _PAGE_KERNEL | _PAGE_NO_CACHE);
+#endif
+
+               SetPageReserved(page);
+               page++;
        }
 
-       err = 0;
-       for (i = 0; i < size && err == 0; i += PAGE_SIZE)
-               err = map_page(va+i, pa+i, flags);
+       /* Free the otherwise unused pages. */
+       while (page < end) {
+               __free_page(page);
+               page++;
+       }
 
        if (err) {
-               vfree((void *)va);
+               free_pages(vaddr, order);
                return NULL;
        }
 
        return ret;
 }
-#endif /* CONFIG_MMU */
 EXPORT_SYMBOL(consistent_alloc);
 
 /*
  * free page(s) as defined by the above mapping.
  */
-void consistent_free(void *vaddr)
+void consistent_free(size_t size, void *vaddr)
 {
+       struct page *page;
+
        if (in_interrupt())
                BUG();
 
+       size = PAGE_ALIGN(size);
+
+#ifndef CONFIG_MMU
        /* Clear SHADOW_MASK bit in address, and free as per usual */
-#ifdef CONFIG_XILINX_UNCACHED_SHADOW
+# ifdef CONFIG_XILINX_UNCACHED_SHADOW
        vaddr = (void *)((unsigned)vaddr & ~UNCACHED_SHADOW_MASK);
+# endif
+       page = virt_to_page(vaddr);
+
+       do {
+               ClearPageReserved(page);
+               __free_page(page);
+               page++;
+       } while (size -= PAGE_SIZE);
+#else
+       do {
+               pte_t *ptep;
+               unsigned long pfn;
+
+               ptep = pte_offset_kernel(pmd_offset(pgd_offset_k(
+                                               (unsigned int)vaddr),
+                                       (unsigned int)vaddr),
+                               (unsigned int)vaddr);
+               if (!pte_none(*ptep) && pte_present(*ptep)) {
+                       pfn = pte_pfn(*ptep);
+                       pte_clear(&init_mm, (unsigned int)vaddr, ptep);
+                       if (pfn_valid(pfn)) {
+                               page = pfn_to_page(pfn);
+
+                               ClearPageReserved(page);
+                               __free_page(page);
+                       }
+               }
+               vaddr += PAGE_SIZE;
+       } while (size -= PAGE_SIZE);
+
+       /* flush tlb */
+       flush_tlb_all();
 #endif
-       vfree(vaddr);
 }
 EXPORT_SYMBOL(consistent_free);